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Currently it is very difficult for connection oriented applications to use a mobile environment. One reason is that Mobile IP requires intermediate software agents to be deployed in the Internet. This infrastructure based mobility scheme offers connectivity to itinerant hosts but incurs significant handoff and tunneling delays along with deployment costs. These delays are particularly harmful for connection oriented applications. In this paper we investigate an alternate mobility scheme which does not require any such infrastructure but only uses an end-point technique and interestingly provides much faster loss-free handoff for connection oriented applications. This End-to-End scheme named Interactive Protocol for Mobile Networks (IPMN) intelligently performs handoff based on information provided by MAC Layer. The network address change is handled by renewing the existing connections by manipulating the TCP/IP stack at the end-points. Also, unlike several other recently proposed end-to-end techniques which require extensive modification of end-protocols, the proposed scheme does not require any functional change in the TCP/IP protocol software. Besides the difference in deployment scenarios, the IPMN offers blazingly fast event based handoff and much faster and simplified transport (no tunneling delay) than MIP. We have implemented IPMN over FreeBSD. In this paper we show the performance advantage of IPMN over MIP with real deployment for three interesting real-time traffic types — www, voice streaming and, steerable/interactive time critical video. | non-battery |
Single walled carbon nanotubes (SWCNT) find their way in various industrial applications. Due to the expected increased production of various carbon nanotubes and nanoparticle containing products, exposure to engineered nanoparticles will also increase dramatically in parallel. In this study the effects of SWCNT raw material and purified SWCNT (SWCNT bundles) on cell behaviour of mesothelioma cells (MSTO-211H) and on epithelial cells (A549) had been investigated. The effect on cell behaviour (cell proliferation, cell activity, cytoskeleton organization, apoptosis and cell adhesion) were dependent on cell type, SWCNT quality (purified or not) and SWCNT concentration.
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Ionic liquid electrolytes containing a certain amount of bis(fluorosulfonyl)imide (FSI) anion can provide reversible capacity for a graphitized negative electrode without any additives such as a solvent. Cyclic voltammetry for a graphitized negative electrode in ionic liquid electrolytes containing FSI with other anions suggests that the reversibility of Li intercalation correlates with the relative quantity (or concentration) of FSI in the electrolytes, and that the correlative tendency depends on the other kind of anion. On the basis of the present results, we discuss the effect of FSI in the ionic systems on a graphitized electrode interface. | battery |
Corrosive (caustic) material ingestion remains a major health issue, particularly in developing countries. The management strategy after corrosive ingestion should be planned according to the signs and symptoms. The management of corrosive ingestion based on endoscopic grading, nothing by mouth, and barium studies should be abandoned. With the new management protocol, esophageal stricture can be predicted with high accuracy using the simple new prognostic DROOL score (≤ 4) rather than endoscopic grading, reduced by immediate oral feeding as soon as the patient can swallow saliva instead of nothing by mouth, diagnosed earlier (10–14 days) by fluoro-endoscopic balloon-assisted esophageal examination for patients with persistent dysphagia instead of relying on a barium study (≥ 21 days), and adequately treated by initiating balloon dilation earlier during the same anesthesia procedure. Fluoroscopically guided balloon dilatation with large balloons (18–20 mm) seems to be safe, with a low frequency of complications and a high success rate. If dilatation fails after a few months, esophagectomy and replacement surgery using the stomach should be considered. The increased risk of developing esophageal carcinoma after ingestion of corrosive substances should be kept in mind.
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An analytical model is developed for the discharge voltage of Li–air batteries with mixed organic/aqueous electrolyte and used to analyze the effects of the oxygen dissolution, solubility, pressure, and diffusivity, reaction rates, and internal resistance on the power density of Li–air batteries. By carefully identifying the model parameters using experimental data it is shown that, for discharge currents above 25 mA cm−2 the power of these batteries is mainly limited by the large internal resistance of the membrane and membrane/electrolyte interfaces (which is currently larger than 100 Ω cm2), while for smaller discharge currents the power is limited by the low oxygen concentration at the reaction sites. The maximum power density can be increased by approximately 1.5 times if the internal resistance is decreased from 100 Ω cm2 to 25 Ω cm2. This relatively small increase in the power density is due to the low dissolution rate and solubility of the oxygen in the liquid electrolyte. Finally, when the battery is operated at maximum discharge power, the oxygen diffusion length in the aqueous electrolyte is under 1 μm, which shows that one needs to use partly wet cathodes in order to achieve high power densities in these batteries. | battery |
A new approach has been developed for the preparation of anodes for rechargeable Li batteries based on nanoparticles of tin as an alloying medium embedded in microporous (pore diameter, <2nm) carbon matrices. It is assumed that if tin particles are confined within the carbon micropores, they may exhibit better cyclability upon alloying–dealloying with lithium, since the detrimental effect of the volume expansion of Li x Sn upon alloying can be avoided. A volatile compound of tin, SnCl4, was physisorbed to the carbon surface. This was followed by hydrolysis to SnO2 and by high temperature degassing, which completed the hydrolysis and removed any volatile residue. Using SEM, EDAX and XRD analyses, we could show that we indeed obtained porous carbon, with particles of tin oxide within the microporous system. These matrices were tested as negative electrodes for secondary Li batteries. At this early stage of the study, a reversible capacity as high as 305mAhg−1 was obtained (carbon and Sn), which means that the capacity of the Li–tin alloying was not to far from its theoretical value. The next steps in this study are: 1. Increasing the amount of tin that can be included in the carbon matrices. 2. The development of the preceding reduction process of SnO2 to Sn, which will reduce pronouncedly the initial irreversible capacity. | battery |
To explore the surface state of electrocatalysts, herein we developed a surface laser modification (pulsed laser ablation, PLA) approach for the fabrication of NiCo2O4-δ with substantial inner oxygen vacancies (Vo ·· ) and higher exterior Ni3+/Ni2+ ratio. The separated NiCo2O4 nanoplates were transformed to cross-linked NiCo2O4-δ nanostructure through PLA strategy. As compare with the primordial NiCo2O4 produce, the laser-modificated NiCo2O4-δ exhibits higher capacitance, lower overpotential and better electrocatalytic performance. The first-principles calculation proves that the additional energy level is introduced between the valence band and conduction band of L-NiCo2O4-δ. The additional energy level not only benefits the hopping of electrons, but also inhibits the recombination of electron-hole pairs. The X-ray photoelectron spectrum (XPS) confirms that the active sites of the electrocatalytic reaction are Vo ·· , suggesting that the electron structure of catalyst could be adjusted by PLA. The high electrocatalytic activity of laser-modificated NiCo2O4-δ could be ascribed to the synergistic effect of increased number of inner Vo ·· , higher electrochemically active surface area, and dominated Nioct. Our findings might inspire new thoughts on the tuning the surface state and electronic structure of electrocatalyst. | battery |
A tin–carbon composite synthesized by high energy mechanical milling (HEMM) technique is characterized here as an anode material for lithium ion battery. The composite morphology and structure are studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD), respectively, and its electrochemical behavior is characterized by cyclic voltammetry (CV) and galvanostatic cycling in lithium cell. The electrode evidences highly nanostructured morphology and enhanced lithium–tin alloying–de-alloying process stability as the mechanical milling time is increased, with capacity ranging from 500 to 400mAhg−1. Further important characteristic of the tin–carbon nanostructure reported here is the very high rate capability, extending up to 2Ag−1, that finally allows to its application in a high voltage, high rate lithium ion cell using the LiNi0.5Mn1.5O4 spinel cathode. The cell shows a working voltage of 4.3V and a capacity of 120mAhg−1 obtained at 1C rate. The very promising features of the cell, its high energy and power density, and the low cost of the involved materials, suggest that the electrode reported here can be efficiently used as an anode in advanced configuration lithium ion battery. | battery |
Lithium-rich layered oxides have being regarded as one of the most promising cathodes for next generation high energy density lithium ion batteries due to their extremely high capacity beyond 250mAhg−1. Among which, Ru-based lithium-rich layered oxides attract special research interests recently for their relatively low irreversible capacity loss during initial cycle and good rate performance. However, as a typical Ru-based lithium-rich layered oxides, Li2RuO3 suffers severely from poor cycling stability and huge voltage decay upon prolonged cycling. Here, we propose a mono-valence cationic substitution strategy of Na+ ions into Li2RuO3 lattice to form Li2-xNaxRuO3 (x=0, 0.02, 0.06, 0.1) series and systematically investigate their electrochemical properties. The results show that Na+ substitution significantly enhance electrochemical performance of Li2RuO3. Specifically, Li1.94Na0.06RuO3 exhibits the best cycling stability, possessing capacity of over 220mAhg−1 after 50 cycles at 1C rate and retaining energy density of 673Whkg−1 after 50 cycles at 0.2C rate. Li1.9Na0.1RuO3 displays the least voltage decay with only 61mV after 50 cycles compared with 228mV for Li2RuO3. The Na-doped Li2RuO3 samples in this work are leading the electrochemical performance of all ever reported Ru-based lithium-rich layered oxides previously, providing a new scope for the strategy to rationally design high-performance lithium-rich layered oxides with balanced cycling stability and voltage maintainance. | battery |
The electrochemical behavior of lead, lead–antimony, and lead–calcium–aluminium–tin alloys has been studied in solutions containing various concentrations of sulfuric and phosphoric acids. The dependence of these electrode processes on some experimental conditions (mainly sweep rate and potential range) has been studied. The measurements were performed using a cyclic voltammetry technique. The study and the analysis of the morphology of alloys have been performed using a scanning electron microscope (SEM). Cyclic voltammograms of the lead–antimony alloy electrodes, similarly to pure lead electrode, also show the “anodic excursion” peak under some experimental conditions. Well defined current waves, corresponding to the oxidation and reduction processes of Sb, are observed, if the alloy surface is freshly abraded. The oxidation of antimony starts at potentials at which the formation of PbO takes place. The peak current of Sb oxidation reaction decreases during successive cycles, suggesting that Sb dissolves from the alloy surface during the first CV sweeps. Another explanation for this effect might be the formation of a PbSO4 selective membrane. | battery |
Living organisms generate electrical fields. The conduction of electrochemical excitation is a fundamental property of living organisms. Cells, tissues, and organs transmit electrochemical signals over short and long distances. Excitation waves in higher plants are possible mechanisms for intercellular and intracellular communication in the presence of environmental changes. Ionic channels, as natural nanodevices, control the plasma membrane potential and the movement of ions across membranes; thereby, regulating various biological functions. Some voltage-gated ion channels work as plasma membrane nanopotentiostats. Tetraethylammonium chloride and ZnCl2 block K+ and Ca2+ ionic channels. These blockers inhibit the propagation of action potentials induced by blue light, and inhibit phototropism in soybean plants. The irradiation of soybean plants at 450±50nm induces action potentials with duration times of about 0.3ms and amplitudes around 60mV. The role of the electrified nanointerface of the plasma membrane in signal transduction is discussed. | battery |
Magnesium-substituted lithium manganese orthosilicate (Li2MnSiO4) cathode materials with a nominal composition of Li2Mg x Mn1−x SiO4, for x =0.4 and 0.5 are synthesized by a solid-state route, at 700°C in argon. The samples are characterized using powder X-ray and neutron diffraction, scanning electron microscopy, and galvanostatic cell-cycling. Rietveld analyses of the powder X-ray and neutron diffraction data show the formation of a monoclinic P21/n structure related to gamma lithium phosphate with no significant impurity peaks. This structure of the Mg-substituted samples is in contrast to the unsubstituted Li2MnSiO4 compound that has a Pmn21 structure when synthesized under the same conditions. Unit-cell volumes of the Mg-substituted materials are intermediate between those of the P21/n structure of Li2MnSiO4 and the isostructural low-temperature form of Li2MgSiO4, indicating the formation of a solid solution. The Mg-substituted materials feature mixed Mg/Mn cation sites, although no evidence of Li/Mn, Li/Mg or Li/Mg/Mn mixed sites are found. The Li2Mg x Mn1−x SiO4 cathodes show improved electrochemical performance over that reported for the unsubstituted Li2MnSiO4 P21/n phase. The Li2Mg x Mn1−x SiO4 cathode performance remains limited by its poor electronic properties and the large particle size of the solid-state synthesized products. Optimization of the synthesis conditions is likely to lead to enhanced electrochemical performance. | battery |
Iron vanadate, FeVO4 nanoparticles are synthesized by simple co-precipitation method and explored as the pseudocapacitor negative electrode for the first time. The structural analysis shows the highly crystalline nature and phase purity of the material. The morphological features of FeVO4 particles are polyhedral in shape and are in the range of 100–200nm. The well defined lattice fringes corroborate the highly crystalline nature of FeVO4. The FeVO4 electrode exhibits a pronounced supercapacitive performance in 1M KOH electrolyte than 1M NaOH and 1M LiOH electrolytes due to its smaller hydration sphere radii, increased mobility and ionic conductivity. The obtained higher specific capacitance of 972Fg−1 at 2mVs−1 and 922Fg−1 at 2mAcm−2, inferred that it could be utilized as a suitable negative electrode. On the other hand, LiCoPO4 is tested as the positive electrode (0 to 0.5V) for the first time and delivers a specific capacitance of 320Fg−1 at 5mVs−1. Finally, an asymmetric supercapacitor is fabricated using FeVO4 as negative and LiCoPO4 as positive electrodes. The device exhibits an excellent energy density of 21Whkg−1 with a power density of 1326Wkg−1 in the potential range between 0 to 1.6V. | battery |
The electrochemical behaviour of a superporous activated carbon (named as ANK3) with a tailored porosity (high apparent specific surface area and a high volume of micropores with an average pore size of around 1.4 nm) is analysed in different non-aqueous electrolytes. ANK3 shows very high capacitance (higher than 160 F g−1) values in solvent-free electrolytes at different temperatures (20, 40 and 60 °C) as well as in 1 M Et4N BF4/PC, 1 M PYR14 BF4/PC and 1 M PYR14 TFSI/PC. The tailored porosity of the ANK3, makes possible to obtain very high capacitance values, making this superporous activated carbon a promising candidate to be used as electrode for electrochemical capacitors using both organic and ionic liquid electrolytes. It is also confirmed that several parameters, such as the ion/pore size ratio, the ion shape, the ion solvation and the conductivity and viscosity of the electrolyte have a strong influence on the electrochemical behaviour of the ANK3. | battery |
Energy harvesting from the environment by portable and flexible power sources can power a variety of devices sustainably. Chen et al. report a hybrid power textile with solar cells and triboelectric nanogenerators that can simultaneously harvest solar and mechanical energy.
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The targeted optimization of Li-ion batteries (LIBs) requires a fundamental understanding of the wide variety of interdependencies between electrode design and electrochemical performance. In the present study, the effects of thickness and porosity on the electrochemical performance and Li-ion insertion kinetics of LiNi0.6Co0.2Mn0.2O2-based (NCM-622) cathodes are investigated. Cathodes of different thickness and porosity are prepared and analyzed regarding their rate capability. The polarization behavior is investigated using electrochemical impedance spectroscopy. A simple mathematical model is employed to estimate the impact of Li-ion diffusion limitations in the electrolyte. The results are considered at both, the materials and the full-cell level. The design parameters are found to have distinct impact on the electrolyte, contact and charge transfer resistance as well as the Li-ion diffusion limitations in the electrolyte, significantly influencing the rate capability. The results attest an inherent tradeoff between energy and power density. The insights of this study can be used straightforward for the optimization of gravimetric and volumetric energy density of LIBs depending on the desired application. | battery |
The renewed interest in two-dimensional materials, particularly transition metal dichalcogenides, has been explosive, evident in a number of review and perspective articles on the topic. Our ability to synthesize and study these 2D materials down to a single layer and to stack them to form van der Waals heterostructures opens up a wide range of possibilities from fundamental studies of nanoscale effects to future electronic and optoelectronic applications. Bottom-up and top-down synthesis and basic electronic properties of 2D chalcogenide materials have been covered in great detail elsewhere. Here, we bring attention to more subtle effects: how the environmental, surface, and crystal defects modify the electronic band structure and transport properties of 2D chalcogenide nanomaterials. Surface effects such as surface oxidation and substrate influence may dominate the overall transport properties, particularly in single layer chalcogenide devices. Thus, understanding such effects is critical for successful applications based on these materials. In this review, we discuss two classes of chalcogenides – Bi-based and Mo-based chalcogenides. The first are topological insulators with unique surface electronic properties and the second are promising for flexible optoelectronic applications as well as hydrogen evolution catalytic reactions.
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Carbon-coated Li3V2(PO4)3 was firstly prepared at 850 °C via two-step reaction method combined sol–gel and conventional solid-state synthesis by using VPO4/carbon as an intermediate. Two different carbon sources, citric acid and glucose as carbon additives in sequence, ultimately deduced double carbon-coated Li3V2(PO4)3 as a high-rate cathode material. The Li3V2(PO4)3/carbon with 4.39% residual carbon has a splendid electronic conductivity of 4.76×10−2 S cm−1. Even in the voltage window of 2.5–4.8 V, the Li3V2(PO4)3/carbon cathode can retain outstanding rate ability (170.4 mAh g−1 at 1.2 C, 101.9 mAh g−1 at 17 C), and no degradation is found after 120 C current rate. These phenomena show that the two-step carbon-coated Li3V2(PO4)3 can act as a fast charge-discharge cathode material for high-power Li-ion batteries. Furthermore, it's believed that this synthesize method can be easily transplanted to prepare other lithiated vanadium-based phosphates. | battery |
Sn-SnO2/C photocatalysts with visible light activity have been successfully synthesized by a simple heat-treating process using SnCl4 as precursor. The Sn-SnO2 heterojunction is built by depositing of metallic Sn on crystal lattice oxygen of as-formed SnO2, which obviously increase the amount of adsorbed oxygen on the surface of catalyst. The as-synthesized catalysts display higher photocatalytic activity than SnO2 and SnO2/C for degradation of reactive brilliant blue KN-R under visible light irradiation. The enhancement of photocatalytic performance of Sn-SnO2/C can be attributed to the formation of metallic Sn on the surface of catalysts. The metallic Sn and adsorbed oxygen as the sinks of photoinduced electron and electronic scavenges, respectively, hinder the recombination of photoexcitated electron-hole pairs, sequentially enhance the photocatalytic activity. Furthermore, a possible growth mechanism of the Sn-SnO2/C photocatalysts was proposed.
| battery |
The kinetics of Li-ion deintercalation in Li1.12[Ni0.5Co0.2Mn0.3]0.89O2 samples is studied by electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT) during the first charge process. The impedance response of Li1.12[Ni0.5Co0.2Mn0.3]0.89O2 largely depends on the open-circuit voltage (OCV) of the cell, showing that the mechanism of electrode kinetics under different potentials is dominated by different electro-chemical reactions. Meanwhile, the equivalent circuit is proposed to simulate the EIS data, deducing the circuit elements (R i and C i) which are normally modeled as a multistep process of electro-chemical reactions. The change trend of R sf (the resistance of SEI film) and R ct (the charge-transfer resistance) in the first charge process are exactly similar. The C dl (double-layer capacitance) as a function of voltage gradually increases, particularly after 4.5V. The maximum of C sf (the film capacitor) observed in the first charge process shows that the most intensive ionic fluxes will appear when the Li1.12[Ni0.5Co0.2Mn0.3]0.89O2 electrode reach to the transient equilibrium at different levels of deintercalation. To study the faster capacity fading of Li1.12[Ni0.5Co0.2Mn0.3]0.89O2 during the first charge process, the Li-ion diffusion coefficient (D Li) is also calculated based on the results of EIS and GITT. | battery |
Thin films of LiCoO2 with a preferred c-axis orientation were prepared by pulsed laser deposition. Thin films deposited for 1–2h had a preferred c-axis orientation, but films deposited for 3h and longer lost the preferred orientation. The textures of these films were investigated in detail by transmission electron microscopy and selected area electron diffraction. The electrochemical properties of these films were compared by cyclic voltammetry and alternating current impedance spectroscopy. In the cyclic voltammograms of the c-axis oriented films, the anodic and cathodic peaks corresponding to the first-order phase transition at around 3.9V were sharp and their peak separation was small due to their thin and uniform texture. However, their smooth surface and texture of the aligned (003) planes gave a larger charge-transfer resistance and a smaller apparent diffusion coefficient in the direction normal to the substrate, respectively, which resulted in poor utilizations (∼50%) of the active material. The reactivity in the single-phase region at potentials more positive than 4.0V was lower than that of randomly oriented films. | battery |
A novel carbon material for use in lithium–sulfur batteries is fabricated from the seaweed Enteromorpha prolifera, a renewable source that grows rapidly in the sea near Qingdao, China, during the summer. The E. prolifera-derived carbon (EPC) possesses a multilevel micropore–mesopore structure and a certain amount of oxygen- and nitrogen-containing functional groups. In addition, the hierarchical porous carbon also possesses a high specific surface area of 3536.58 m2 g−1 and a large pore volume of 1.754 cm3 g−1. The carbon can thus be loaded with a high sulfur content (EPC/S, 74.8 wt%), making it a promising candidate for use as the cathode material in lithium–sulfur batteries. The EPC was characterized using field-emission scanning electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, the Brunauer–Emmett–Teller method, and other methods. The EPC/S cathode exhibited superior electrochemical performance; the first discharge capacity was as high as 1328 mA h g−1 at 0.1 C. Further, the capacity was 520 mA h g−1 after 100 cycles at 0.5 C and 510 mA h g−1 after 100 cycles at 1 C. | battery |
Poly(ethylene oxide)–lithium salt composite electrolytes containing two different derivatives of calix[4]arene were tested as anion complexing agents for I− and CF3SO3 −. Both calix[4]arene derivatives studied have identical anion coordination groups but they have different compatibility with the polymer matrix obtained by chemical linking of the oligo(ethylene oxide) chains to one of the studied calixarenes. The impedance spectroscopy studies showed that the addition of the anion receptor significantly changes the conductivity. The character of this changes strongly depends on the receptor used while the electrochemical stability of these two calixarene receptors measured by cyclic voltammetry is similar. It was also proved that addition of the anion receptor strongly changes the polymer matrix morphology and thermal behavior. By the comparison with the liquid systems which electrical properties were similar to the polymer matrix, we can assume that these changes are a result of anion–receptor interactions. | battery |
Novel electrode materials with nominal compositions of (1− x)LiVO2·xLi2TiO3 (0≤ x ≤0.6) were synthesized by carbothermal reduction reaction. All the materials were identified to have a layered structure and can be considered as a solid solution related to LiVO2–Li2TiO3 system, in which Li layers was alternately stacked with the layers made of mixture of Li, V, and Ti in a ccp array of oxygen. The redox reaction associated with vanadium ions was not reversible in LiVO2; however, introduction of the redox couple into Li2TiO3 made it much more reversible. A reversible capacity of about 120mAhg−1 remained after 90 cycles for the samples with x =0.5 and 0.6, when they were cycled in the voltage range of 1.0–4.8V. | battery |
A high strength Li-Garnet solid electrolyte composite ceramic is successfully prepared via conventional solid state method with Li6.4La3Zr1.4Ta0.6O12 and nano MgO powders. Well sintered ceramic pellets and bars are obtained with 0–9 wt.% MgO. Fracture strength is approximately 135 MPa for composite ceramics with 5–9 wt.% MgO, which is ∼50% higher than that of pure Li6.4La3Zr1.4Ta0.6O12 (90 MPa). Lithium-ion conductivity of the composite is above 5 × 10−4 S cm−1 at room temperature; comparable to the pure Li6.4La3Zr1.4Ta0.6O12 material. SEM cross-sections of the composite ceramic shows a much more uniform microstructure comparing with pure ones, owing to the grain growth inhibition effect of the MgO second phase. A battery cell consisting of Li/composite ceramics/Sulfur-Carbon at 25 °C exhibits a capacity of 685 mAh g−1 at 0.2 C at the 200th cycle, while maintaining a coulombic efficiency of 100%. These results indicate that the composite ceramic Li6.4La3Zr1.4Ta0.6O12-MgO is promising for the production of electrolyte membrane and fabrication of Li-Sulfur batteries. | battery |
Accumulating evidence suggests that not only diseases of old age, but also normal aging, affect elderly adults’ ability to draw on the framework theories that structure our abstract causal-explanatory knowledge, knowledge that we use to make sense of the world. One such framework theory, the cross-culturally universal vitalist biology, gives meaning to the abstract concepts life and death. Previous work shows that many elderly adults are animists, claiming that active, moving entities such as the sun and the wind are alive (Zaitchik & Solomon, 2008). Such responses are characteristic of young children, who, lacking an intuitive theory of biology, distinguish animals from non-animals on the basis of a theory of causal and intentional agency. What explains such childlike responses? Do the elderly undergo semantic degradation of their intuitive biological theory? Or do they merely have difficulty deploying their theory of biology in the face of interference from the developmentally prior agency theory? Here we develop an analytic strategy to answer this question. Using a battery of vitalist biology tasks, this study demonstrates—for the first time—that animism in the elderly is due to difficulty in deployment of the vitalist theory, not its degradation. We additionally establish some powerful downstream consequences of theory deployment difficulties, demonstrating that the elderly’s use of the agency theory is not restricted to animist judgments—rather, it pervades their explicit reasoning about animates and inanimates. Extending the investigation, we identify specific cognitive mechanisms implicated in adult animism, finding that differences between young and elderly adults are mediated and moderated by differences in inhibition and shifting mechanisms. The analytic strategy developed here could help adjudicate between degradation and deployment in other conceptual domains and other populations. | non-battery |
In this manuscript, performance of a novel concentrated solar thermal collector with evacuated tube is studied. The focus is the optimization of cost and performance in respect to commercially available medium temperature collectors (100–300 °C) using thermal and economic index of heat generation system also known as Levelized Cost of Heat. In this project, Levelized Cost of Heat is optimized with material cost reduction while maintaining high thermal performance using economical aluminum fin (instead of copper), a glass cover and highly truncated aluminum reflector. The reflector is truncated using the nonimaging optics methods in order to maximize the optical efficiency while minimizing the material consumption. Also, in order to predict the thermal performance of the proposed collector, analytical and numerical simulation are studied. Finally, the collector is experimentally tested in three stages to measure maximum temperature, maximum efficiency and thermal efficiency at various temperature of heat transfer fluid. The mathematical, numerical and experimental results were found to have good agreement. The results indicate that the collector can operate with optical efficiency of 60%, maximum temperature of 350 °C, thermal efficiency of 51% and 42% at 100 °C and 200 °C respectively while the cost of energy is as low as 2.9 cents/kWh. | battery |
This paper reports studies on the morphology, thermal stability, NMR and electrical spectroscopy of the first lithium zeolitic inorganic–organic polymer electrolyte (Z-IOPE) with the formula [Fe x Pd y (CN) z Cl v (C2n H4n+2O n+1)Li l ]. Both 1H and 7Li NMR linewidth, spin-lattice relaxation, and pulsed field gradient diffusion measurements were conducted, and the results suggest that the lithium ion transport is correlated with polymer mobility, as in the case of “conventional” polymer electrolytes. A detailed study of the mechanism of ion conduction in bulk material has been carried out also by electrical spectroscopy measurements in the 10 mHz–1 GHz range. The electrical spectra for frequencies higher than 15 kHz evidenced the presence of relaxation events associated to local ion motion dynamics and long range diffusion. These two phenomena were interpreted in terms of (a) ion hopping processes; (b) site relaxations; and (c) host medium reorganization processes. Taken together, these studies demonstrated that at temperatures higher than 35°C, the Z-IOPE conducts ionically by charge transfer mechanisms mainly regulated by ion hopping between equivalent polyether coordination sites followed by correlated host medium reorganizations. Finally, a conductivity of 5.3×10−5 S cm−1 at 35°C classifies this hybrid inorganic–organic network as a good lithium ion conductor. | battery |
We have investigated an inorganic lithium battery system in which LiCoO2 is used as the positive electrode and lithium, intercalated into graphite, serves as negative electrode. The conducting salt is lithium tetrachloroaluminate (LiAlCl4). The electrolyte is based on SO2. It has been shown that a layer of lithium hydroxide is present on the surface of the lithium cobalt oxide. This has a negative impact on the stability of the electrode. To improve stability, we have developed a purification process for removing the lithium hydroxide from the surface of the positive electrode. After purification the cells show no significant change in either capacity or internal resistance when cycled. Up to 70% of the theoretical capacity of electrodes which have been purified in this way can be used without any negative effects being observed. To prevent the deposition of metallic lithium leading to a hazardous situation, a new safety concept was developed whereby local short circuits are allowable. Safe functioning of the new concept has been demonstrated with tests on complete cells. | battery |
Layered xLi2MnO3·(1 −x)LiMnO2 (x =0.57, 0.48, and 0.44) nanoplates are firstly prepared by pyrolysis reducing the electrochemically inactive monoclinic Li2MnO3 nanoplates, which is synthesized via a solid-state reaction by using home-made MnO2 nanoplates as self-template. The obtained xLi2MnO3·(1− x)LiMnO2 nanoplates have a diameter of ∼200nm and thickness of ∼60nm with high crystallinity and the transition metal layers parallel to the plate’s radial direction. Although these xLi2MnO3·(1 −x)LiMnO2 nanoplates cause a longer Li+ diffusion distance, and then a lower reversible capacity as compared to the nanoparticle-like counterpart, the nanoplate-like morphology of these xLi2MnO3·(1− x)LiMnO2 (especially with x <0.5) are beneficial for retarding the layer-to-spinel phase transformation during the charge/discharge processes, and resulting in significant improvement of the cyclic stability. Moreover, the reduced reversible capacity caused by the longer Li+ diffusion distance of the nanoplate-like morphology can be offset by decreasing the x value, and the xLi2MnO3·(1− x)LiMnO2 nanoplates with x =0.44 performs a maximum reversible capacity as high as 270mAhg−1 with a well cyclic performance. The present findings indicate that the cyclic performance and reversible capacity of xLi2MnO3·(1 −x)LiMnO2 can be improved by tailoring the particle’s morphology and composition, and demonstrate a simple and effective strategy for the development of the Co/Ni-free Mn-based layered Li-rich cathode materials with good cyclic and high reversible capacity. | battery |
The development of simple and green synthetic strategies to obtain porous carbon with both high energy density and power density for carbon-based supercapacitors has motivated the utilization of sustainable biomass materials, due to their unique microstructures and high heteroatom contents. Herein, a novel, green and efficient activation agent magnesium carbonate is proposed to prepare nitrogen self-doped hierarchical porous carbon materials derived from pine pollen for superior carbon-based supercapacitors. The obtained carbon has a large surface area of 1311.2 m2 g−1, hierarchical porous structure with interconnected meso-/macropores and high nitrogen, oxygen contents. When applied as supercapacitor electrode in a three-electrode system, the carbon-based electrode exhibits a high specific capacitance of 419.6 F g−1 at a current density of 1 A g−1, good rate retention of 60.3% from 1 to 100 A g−1 and superior long-term cycling stability with 2.6% loss of its initial capacitance after 10,000 cycles in 6 M KOH aqueous electrolyte. Additionally, the assembled symmetric supercapacitor can work at a high voltage of 2.0 V in 1 M Na2SO4 aqueous electrolyte, and deliver an ultrahigh energy density of 34.9 Wh kg−1 at a power density of 181.0 W kg−1. | battery |
Lithium–sulfur battery is amongst the most promising next-generation energy storage technology owing to their high theoretical capacity and energy density. Nevertheless, the notorious shuttle effect of lithium polysulfides (LiPSs) seriously impedes its practical applications. Here, we report an all-CVD approach to realize the direct growth of ReS2@N-doped graphene (NG) heterostructure, which serves as an ultralight high-performance interlayer for elevated LiPS regulation via easy transfer onto the commercial separator. In contrast to the traditional interlayers constructed via vacuum filtration of nanostructured materials that inevitably increase the thickness and weight of the separator, our all-CVD-enabled ReS2@NG film possesses an area of 15 mm × 100 mm, a thickness of ~0.5 μm and a negligible areal weight of 80–90 μg cm−2. Benefiting from the two-dimensional (2D) vertically-erected nanostructure, adsorptive ReS2-conductive NG interface, and favorable electrical conductivity, thus-derived ReS2@NG interlayer readily enhances reaction kinetics for LiPS conversion and boosts the reutilization of trapped LiPS whilst guaranteeing smooth transportation of lithium ions. Accordingly, an initial discharge capacity of 854 mAh g−1 with an average capacity decay of 0.064% per cycle after 800 cycles can be harvested at 2.0 C. Even at a high sulfur loading of 6.4 mg cm−2, an initial areal capacity of 6.1 mAh cm−2 can be gained, which still retains 5.8 mAh cm−2 after 40 cycles at 0.1 C. This work is anticipated to shed light upon the construction of CVD-enabled versatile 2D heterostructures for enriching the interlayer design with multifunctionality and cost-effectiveness. | battery |
Although imitation problems have been associated with autism for many years, the underlying mechanisms of these problems remain subject to debate. In this article, the question whether imitation problems are caused by selection or correspondence problems is explored and discussed. This review revealed that hypotheses on the nature of imitation problems in autism are complicated and inconclusive at the present time. There is some evidence for impaired selection, especially implicating poor preferential attention to biological motion and poor ascription of intention to action. There is also some evidence that both transformations of perspectives and mapping of visual to motor information are impaired, characterized as correspondence problems. However, it is not yet clear how poor selection processes contribute to correspondence problems and vice versa. Insight in this interaction may provide a valuable contribution to our understanding of imitation problems in autism. For further research we recommend that tasks should be constrained to target as few mechanisms as possible in given experiments. | non-battery |
Engineering crystal facets to enhance their functionalities often require complex processing routes to suppress the growth of surfaces with the lowest thermodynamic energies. Herein, we report a unique method to control the morphologies of β-MnO2 crystals with different occupancy of {100}/{111} facets through the effect of K+ cations. Combining aberration-corrected scanning transmission electron microscopy (STEM), ultramicrotomy, and dynamic functional theory (DFT) simulation, we clarified that the β-MnO2 crystals were formed through a direct solid-state phase transition process. Increasing the concentration of K+ cations in the precursor gradually changed the morphology of β-MnO2 from bipyramid prism ({100}+{111} facets) to an octahedron structure ({111} facets). The K+ cations controlled the morphology of β-MnO2 by affecting the formation of α-K0.5Mn4O8 intermediate phase and the subsequent phase transition. Utilizing the β-MnO2 crystals as the cathode for Li-ion batteries showed that highly exposed {111} facets offered β-MnO2 crystal better rate performance, with ~70% capacity retention when the charge-discharge rate increased from 20 mA/g to 200 mA/g. Our work revealed a new mechanism to tune the morphology of this earth-abundant metal oxide crystal, which could be used to adjust its electrochemical performance for different applications, such as supercapacitors and catalysts for metal-air batteries and fuel cells. | battery |
Lithium Ion batteries have to be significantly improved to fulfill the challenging needs in electromobility or large scale energy storage technology. In this context the use of model electrodes such as single-crystals or thin films allows well-defined mechanistic studies. Here we present a detailed electrochemical investigation of the lithiation–delithiation behavior of Au thin film model electrodes in ionic liquid electrolyte. Cyclic voltammetry, galvanostatic-, stepwise potentiostatic lithiation–delithiation cycles, as well as galvanostatic intermittent titration technique, GITT, measurements were performed. We found nearly identical mechanism of Li insertion and extraction in these three types of measurements at different current levels. The mechanism of alloying or lithiation deviated from the mechanism of dealloying or delithiation. While during the lithiation process two main plateaus related to phase transformations occur in the potential–time curves three main plateaus appear during delithiation. First results of theoretical simulations confirm a high number of possible metastable phases in the Li–Au system. The measurements also point to the influence of SEI-film formation on the cycling behavior. Based on these insights a mechanistic sequence and a phase evolution diagram for the electrochemical alloying of Li with Au are presented. | battery |
In this work, the Zn-Al layered double hydroxide (Zn-Al LDH) is exfoliated. Ambient temperature ion exchange and chemical exfoliation route have been developed to synthesize the exfoliated layered double hydroxide/graphene compounds (Exfoliated LDH/G). The as-prepared Exfoliated LDH/G nanocomposites demonstrate no obvious impurity and good morphology, being characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). Here we intensively study the electrochemical performances of Exfoliated LDH/G and pure LDH electrodes for Zn-Ni secondary battery. It was found that the as-prepared Exfoliated LDH/G here exhibits higher and wide discharge voltage plateaus due to the well electrical conductivity and lower self-corrosion, which could promote charge-transfer of the exfoliated LDH. The preliminary results show that the Exfoliated LDH/G displays superior Zn-Ni secondary battery performance with outstanding reversible capacity, prominent cyclic performance (343 mA h g−1 after 1200 cycles at 1 C), highlighting the practicability of the self-assembly Exfoliated LDH/G for maximum anodic utilization of exfoliated LDH for power storage in Zn-Ni secondary battery. | battery |
Single-cell isolation following time-lapse imaging (SIFT) enables high-throughput screening of complex and dynamic phenotypes from pooled bacterial libraries. SIFT was used to generate ultraprecise synthetic gene oscillators.
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Several metals (Cu, Fe, Al, Ti, and Cr) as current collector for lithium-ion battery were investigated to understand their electrochemical behavior and passivation process in a non-aqueous alkyl carbonate solution containing LiPF6 salt. From cyclic voltammetric study, it was found that Cu and Fe metals were dissolved into the electrolyte below 4V vs. Li/Li+. Alternatively, Al and Ti were stable up to 5V vs. Li/Li+. Their scratched surfaces at 5V vs. Li/Li+ were polarized in a transient mode and it was found that the surfaces were passivated during the polarization test. Formed passive film was composed of two hybrid layers: outer layer by metal (Al and Ti) fluoride and inner by metal oxide, as confirmed by time-of-flight secondary ion mass spectroscopy. Presence of HF in the electrolyte was indispensible to form the metal fluoride layer on the oxide layer. The outer fluoride layer would protect the inner oxide layer and metal substrate from HF attack, bringing about satisfactory corrosion resistance under lithium-ion battery environment. | battery |
A solvothermal method was used to prepare Na1.25Ni1.25Fe1.75(PO4)3 nanoparticles, a new promising electrode material for lithium-ion batteries. The composition and the crystal structure were determined by 57Fe Mössbauer spectroscopy and powder X-ray diffraction Rietveld refinements and confirmed by magnetic measurements. The structural formula □0.75Na1.25Ni1.25Fe1.75(PO4)3 was obtained showing a significant amount of Na vacancies, which enhances Li diffusion. Na1.25Ni1.25Fe1.75(PO4)3 was used as negative and positive electrode material and shows excellent electrochemical performances. As negative electrode in the voltage range 0.03-3.5 V vs. Li+/Li, the first discharge at current density of 40 mA g−1 delivers a specific capacity of 1186 mAh g−1, which is almost three times its theoretical capacity (428 mAh g−1). Then, reversible capacity of 550 mAh g−1 was obtained at 50 mA g−1 with high rate capability (150 mAh g−1 at 500 mA g−1) and capacity retention of 350 cycles. As positive electrode material, specific capacities of about 145 and 99 mAh g−1 were delivered at current densities of 5 and 50 mA g−1, respectively, in the voltage range of 1.5–4.5 V vs. Li+/Li. In addition, we show that the use of solvothermal synthesis contributes to the synthesis of small sized particles leading to good electrochemical performances. | battery |
Lithium iron phosphate olivine (LFP) and lithium manganese oxide spinel (LMO) are competitive and complementary to each other as cathode materials for lithium ion batteries, especially for use in hybrid electric vehicles and electric vehicles. Interest in these materials, due to their low cost and high safety, has pushed research and development forward and toward high performance in terms of rate capability and capacity retention or cyclability at a high temperature of around 60 °C. From the view point of basic properties, LFP shows a higher gravimetric capacity while LMO has better conductivities, both electrically and ionically. According to our comparison experiments, depending on the material properties and operational potential window, LFP was favored for fast charging while LMO led to better discharge performances. Capacity fading at high temperatures due to metal dissolution was revealed to be the most problematic issue of LFP and LMO-based cells for electric vehicles (EVs), with thicker electrodes, in the case of no additives in the electrolyte and no coating to prevent metal dissolution on cathode materials. Various strategies to enhance the properties of LFP and LMO are ready for the realization of EVs in the near future.
| battery |
Noninvasive detection of innate immune function such as the accumulation of neutrophils remains a challenge in many areas of clinical medicine. We hypothesized that granulocytes could generate volatile organic compounds. | non-battery |
In this study, a novel large-scale stand-alone solar/wind/battery hybrid power generation system is designed and constructed. It consists of a photovoltaic (PV) array, a wind energy conversion system (WECS), a battery bank, a bidirectional DC/DC converter, two unidirectional DC/DC converters, a unified maximum power point tracking (MPPT) controller, a control unit, and a DC/AC inverter. The stand-alone solar/wind/battery hybrid system presented in this study combines two renewable resources (solar and wind) with a back-up battery bank used as a standby power source to produce electric energy. Moreover, it maximally converts solar and wind energies into electric energy because it uses a novel fast and highly accurate unified MPPT technique that concurrently tracks the maximum power points of both PV system and WECS. Other works reported in the literature are mostly simulation based works (models), and moreover, there is not any new MPPT consideration in them. It is experimentally verified that the large-scale constructed system is a high-efficient stand-alone solar/wind/battery hybrid power generation system that produces electric energy under different environmental conditions such as cloudy sky, so it can be widely used in remote areas. | battery |
Si microwire-array solar cells with Air Mass 1.5 Global conversion efficiencies of up to 7.9% have been fabricated using an active volume of Si equivalent to a 4 μm thick Si wafer. These solar cells exhibited open-circuit voltages of 500 mV, short-circuit current densities (Jsc) of up to 24 mA cm-2, and fill factors >65% and employed Al2O3 dielectric particles that scattered light incident in the space between the wires, a Ag back reflector that prevented the escape of incident illumination from the back surface of the solar cell, and an a-SiNx:H passivation/anti-reflection layer. Wire-array solar cells without some or all of these design features were also fabricated to demonstrate the importance of the light-trapping elements in achieving a high Jsc. Scanning photocurrent microscopy images of the microwire-array solar cells revealed that the higher Jsc of the most advanced cell design resulted from an increased absorption of light incident in the space between the wires. Spectral response measurements further revealed that solar cells with light-trapping elements exhibited improved red and infrared response, as compared to solar cells without light-trapping elements.
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Semi Inter penetrating Polymer Network (IPN) of [poly (ethylene glycol)-polyurethane-polymethylmethacrylate] [60:40]-montmorillonite (MMT) nanocomposites with different weight percentages of MMT are synthesized. The formation of the composite and its structural properties are characterized by Fourier transform infrared, X-ray diffraction pattern (XRD) and scanning electron microscopy (SEM) images. Differential scanning calorimetry (DSC) and XRD patterns show the amorphous nature of the composites. The Thermo Gravimetric Analysis (TGA) shows the enhanced thermal stability of the composite compared with the semi IPN without fillers. The conductivity behavior, frequency dependent modulus properties and dielectric properties of these prepared composites are studied by using ac impedance spectroscopy (EIS) in the frequency range 1Hz-1MHz. It is found from the impedance results that conductivity increases from 2.17×10−7 S/cm to 2.32×10−6 S/cm with increase of MMT concentration up to 5wt % and it decreases with further increase of MMT content. The dielectric analysis shows that dielectric permittivity (ɛ′) and dielectric loss (ɛ″) values decreases with increase in frequency at lower frequency region whereas frequency independent behavior is observed in the high frequency region. The electrical modulus representation shows a peak in the imaginary component. The ionic conduction relaxation times of the composites obtained from this peak maximum are in good correlation with the electrode polarization relaxation time and conductivity values. | battery |
Abstract Project finance has evolved during the years and sectors of applications have changed together with the geographic areas where the technique has been used. Originally project finance was used in sectors with a stable captive market, low technology risk and low country risk. During the years, the technique has been increasingly implemented in riskier sectors and riskier countries. This chapter presents the historic evolution of project finance and PPPs. We first outline the worldwide trends with details regarding the use of the technique in different sectors and geographic macroregions. Then, we present a focus on the PPP subsegment. Here, we carry out the analysis distinguishing between developing and developed countries. Finally, a special focus on the European PPP market is provided. | non-battery |
Improved interfacial resistance was observed in lithium cells by the use of new additives. The additives, nitrile sucrose and nitrile cellulose and their lithium salts, were evaluated in polyvinylidene difluoride (PVDF) thin-film gelled electrolytes containing a mixture of ethylene carbonate (EC) and diethyl carbonate (DEC). The electrochemical properties of the films with and without the additives were measured as a function of temperature and compared. The interfacial resistance (R in) of the films with the additives was significantly lower than that without the additives, especially at sub-ambient temperatures. For example, the R in at −20°C for the films with additives was around 7000Ωcm2 and that for the films without the additives was >20,000Ωcm2. Results obtained from using the additives in lithium-ion (Li-ion) cells show significant improvements in the low frequency resistance of the cells. | battery |
This work presents an up-to-date information on Na-based battery materials. On the one hand, it explores the feasibility of two novel energy storage systems: Na-aqueous batteries and Na–O2 technology. On the other hand, it summarises new advances on non-aqueous Na-ion systems. Although all of them can be placed under the umbrella of Na-based systems, aqueous and oxygen-based batteries are arising technologies with increasing significance in energy storage research, while non-aqueous sodium-ion technology has become one of the most important research lines in this field. These systems meet different requirements of energy storage: Na-aqueous batteries will have a determining role as a low cost and safer technology; Na–O2 systems can be the key technology to overcome the need for high energy density storage devices; and non-aqueous Na-ion batteries have application in the field of stationary energy storage.
| battery |
In a hybrid photovoltaic–thermal (PV/T or PVT) module, electricity and thermal energy are generated simultaneously in the same module. By combining a PV module and a solar thermal collector, more of the solar radiation can be harvested, and the total efficiency of the module is increased. The combination of two technologies in one module also has the potential to reduce the use of materials and the required space. In order to assess and quantify these possibilities, several research groups have presented life cycle assessments (LCA) of different PV/T concepts and installations. This paper presents a review of the published results, and aims to find a common ground. In general, the payback time for both energy and greenhouse gas emissions of the PV/T systems are much shorter than their expected lifetime. However, due to the use of different methods and unclear data sources, it is difficult to make any wide-ranging conclusions about the environmental impact of PV/T modules. | battery |
Molybdenum disulfide (MoS2) anchored carbon nitride (CN) based nanomaterial have been developed by using the hydrothermal method, which confines sulfur on to the CN and is utilized as a sulfur host for Li-Sulfur (LiS) battery. The prepared material CN/MoS2 demonstrated enhanced electrochemical performance with an initial charge-discharge capacity of 1252 mAh g−1 and 1264 mAh g−1 at 0.5C rate, with a reversible capacity of 680 mAh g−1 after 200cycles. The enhanced capacity and cyclic stability for CN/MoS2 in comparison with the bare CN is attributed to anchored MoS2 which can change the structural, physiochemical and increased electrochemical active surface area of CN/MoS2 based hybrid. | battery |
Lithium-ion batteries (LIBs) have been used widely in portable electronics, and hybrid-electric and all-electric vehicles for many years. However, there is a growing need to develop new cathode materials that will provide higher cell energy densities for advanced applications. Several candidates, including Li2MnO3-stabilized LiM′O2 (M′ = Mn/Ni/Co) structures, Li2Ru0.75Sn0.25O3 (i.e., 3Li2RuO3–Li2SnO3), and disordered Li2MoO3–LiCrO2 compounds can yield capacities exceeding 200 mA h g−1, alluding to the constructive role that Li2MO3 (M4+) end-member compounds play in the electrochemistry of these systems. Here, we catalog the family of Li2MO3 compounds as active cathodes or inactive stabilizing agents using high-throughput density functional theory (HT-DFT). With an exhaustive search based on design rules that include phase stability, cell potential, resistance to oxygen evolution, and metal migration, we predict a number of new Li2MIO3–Li2MIIO3 active/inactive electrode pairs, in which MI and MII are transition- or post-transition metal ions, that can be tested experimentally for high-energy-density LIBs.
| battery |
Efforts to replace conventional chromatographic methods for environmental monitoring with cheaper and easy to use biosensors for precise detection and estimation of hazardous environmental toxicants, water or air borne pathogens as well as various other chemicals and biologics are gaining momentum. Out of the various types of biosensors classified according to their bio-recognition principle, nucleic-acid-based sensors have shown high potential in terms of cost, sensitivity, and specificity. The discovery of catalytic activities of RNA (ribozymes) and DNA (DNAzymes) which could be triggered by divalent metallic ions paved the way for their extensive use in detection of heavy metal contaminants in environment. This was followed with the invention of small oligonucleotide sequences called aptamers which can fold into specific 3D conformation under suitable conditions after binding to target molecules. Due to their high affinity, specificity, reusability, stability, and non-immunogenicity to vast array of targets like small and macromolecules from organic, inorganic, and biological origin, they can often be exploited as sensors in industrial waste management, pollution control, and environmental toxicology. Further, rational combination of the catalytic activity of DNAzymes and RNAzymes along with the sequence-specific binding ability of aptamers have given rise to the most advanced form of functional nucleic-acid-based sensors called aptazymes. Functional nucleic-acid-based sensors (FNASs) can be conjugated with fluorescent molecules, metallic nanoparticles, or quantum dots to aid in rapid detection of a variety of target molecules by target-induced structure switch (TISS) mode. Although intensive research is being carried out for further improvements of FNAs as sensors, challenges remain in integrating such bio-recognition element with advanced transduction platform to enable its use as a networked analytical system for tailor made analysis of environmental monitoring. | non-battery |
The doped and milled spinels Li1.05M0.02Mn1.98O3.98N0.02 (M=Ga3+, Al3+ or Co3+; N=S2− or F−) are studied aiming at obtaining an improved charge/discharge cycling performance. These spinels are prepared by a solid-state reaction among the precursors ɛ-MnO2, LiOH, and the respective oxide/salt of the doping ions at 750°C for 72h and milled for 30min. The obtained spinels are characterized by XRD, SEM, and determinations of the average manganese valence n. In the charge and discharge tests, the doped spinels present outstanding initial values of the specific discharge capacity C (117–126mAhg−1), decreasing in the following order: C(Li1.05Al0.02Mn1.98S3.02O3.98)> C(Li1.05Al0.02Mn1.98F3.02O3.98)> C(Li1.05Ga0.02Mn1.98S3.02O3.98)> C(Li1.05Ga0.02Mn1.98F3.02O3.98)> C(Li1.05Co0.02Mn1.98S3.02O3.98)> C(Li1.05Co0.02Mn1.98F3.02O3.98). The doped spinel Li1.05Ga0.02Mn1.98S3.02O3.98 presents an excellent electrochemical performance, with a low capacity loss even after 300 charge and discharge cycles (from 120 to 115mAhg−1 or 4%). | battery |
The research developments with renewable energy source water pumping systems (RESWPSs) are reviewed in this paper. The reported investigations are categorized into five major groups as follows: (i) solar photovoltaic water pumping systems (SPWPSs), (ii) solar thermal water pumping systems (STWPSs), (iii) wind energy water pumping systems (WEWPSs), (iv) biomass water pumping systems (BWPSs) and (v) hybrid renewable energy water pumping systems (HREWPSs). More than a hundred published articles related to RESWPSs are briefly reviewed. Additionally, the limitations with RESWPSs and further research needs are described. This paper concludes that renewable energy sources (RESs) play a vital role in reducing the consumption of conventional energy sources and its environmental impacts for water pumping applications. | battery |
Although cognitive neuroscience has made valuable progress in understanding the role of the prefrontal cortex in human intelligence, the functional networks that support adaptive behavior and novel problem solving remain to be well characterized. Here, we studied 158 human brain lesion patients to investigate the cognitive and neural foundations of key competencies for fluid intelligence and working memory. We administered a battery of neuropsychological tests, including the Wechsler Adult Intelligence Scale (WAIS) and the N-Back task. Latent variable modeling was applied to obtain error-free scores of fluid intelligence and working memory, followed by voxel-based lesion-symptom mapping to elucidate their neural substrates. The observed latent variable modeling and lesion results support an integrative framework for understanding the architecture of fluid intelligence and working memory and make specific recommendations for the interpretation and application of the WAIS and N-Back task to the study of fluid intelligence in health and disease. | non-battery |
A nanocomposite of polyluminol (poly(5-amino-2,3-dihydro-1,4-phthalazinedione)) and reduced graphene oxide nanosheets was electrochemically synthesized, characterized by scanning electron microscopy, X-ray diffraction and electrochemical methods, and its pseudocapacitance behavior was investigated. The excellent supercapacitive properties of the nanocomposite arising from both the electrical double layer capacitance of graphene nanosheets and pseudocapacitance of polyluminol resulted from a synergistic effect of the complementary properties of graphene and polyluminol. The nanocomposite presented a specific capacitance of 218.7Fg−1 at a discharge current of 0.55Ag−1. The nanocomposite was kept >99% of the initial capacitance after 1000 charge/discharge cycles. | battery |
The challenges of providing electricity to rural households are manifold. Ever increasing demand–supply gap, crumbling electricity transmission and distribution infrastructure, high cost of delivered electricity are a few of these. Use of renewable energy technologies for meeting basic energy needs of rural communities has been promoted by the Governments world over for many decades. Photovoltaic (PV) technology is one of the first among several renewable energy technologies that was adopted globally as well as in India for meeting basic electricity needs of rural areas that are not connected to the grid. This paper attempts at reviewing and analyzing PV literature pertaining to decentralized rural electrification into two main categories—(1) experiences from rural electrification and technology demonstration programmes covering barriers and challenges in marketing and dissemination; institutional and financing approaches; and productive and economic applications, (2) techno-economic aspects including system design methodologies and approaches; performance evaluation and monitoring; techno-economic comparison of various systems; and environmental implications and life cycle analysis. The paper discusses the emerging trends in its concluding remarks. | battery |
A model-based dynamic multi-parameter method for peak power estimation is proposed for batteries and battery management systems (BMSs) used in hybrid electric vehicles (HEVs). The available power must be accurately calculated in order to not damage the battery by over charging or over discharging or by exceeding the designed current or power limit. A model-based dynamic multi-parameter method for peak power estimation of lithium–ion batteries is proposed to calculate the reliable available power in real time, and the design limits such as cell voltage, cell current, cell SoC, cell power are all used as its constraints; more importantly, the relaxation effect also is considered. Where, to improve the model’s accuracy, the ohmic resistance of Thevenin model for the lithium–ion battery has been refined; in order to further improve the polarization parameters identification precision, a genetic algorithm has been used to gain the optimal time constant. Lastly, a test with several consecutive Federal Urban Driving Schedules (FUDSs) profiles is carried to evaluate the model-based dynamic multi-parameter method for peak power estimation. The experimental and simulation results indicate that the model-based dynamic multi-parameter method for peak power estimation can calculate the terminal voltage and the current available power much more reliably and accurately. | battery |
Cluster headache is a debilitating primary headache disorder that affects approximately 0.1% of the population worldwide. Cluster headache attacks involve severe unilateral pain in the trigeminal distribution together with ipsilateral cranial autonomic features and a sense of agitation. Acute treatments are available and are effective in just over half of the patients. Until recently, preventive medications were borrowed from non-headache indications, so management of cluster headache is challenging. However, as our understanding of cluster headache pathophysiology has evolved on the basis of key bench and neuroimaging studies, crucial neuropeptides and brain structures have been identified as emerging treatment targets. In this Review, we provide an overview of what is known about the pathophysiology of cluster headache and discuss the existing treatment options and their mechanisms of action. Existing acute treatments include triptans and high-flow oxygen, interim treatment options include corticosteroids in oral form or for greater occipital nerve block, and preventive treatments include verapamil, lithium, melatonin and topiramate. We also consider emerging treatment options, including calcitonin gene-related peptide antibodies, non-invasive vagus nerve stimulation, sphenopalatine ganglion stimulation and somatostatin receptor agonists, discuss how evidence from trials of these emerging treatments provides insights into the pathophysiology of cluster headache and highlight areas for future research. | non-battery |
Mesoporous hollow TiO2 microboxes synthesized by a two-step solvothermal method via CaTiO3 intermediate were applied as host materials for sulfur cathodes of lithium-sulfur batteries. 3TiO2/7S composite containing 70 wt% sulfur exhibited the best electrochemical performance among all composites. A high discharge capacity of 924.8 mAh g−1 was achieved for the 1st cycle and 67.4% of it could be retained after 200 cycles at 0.2 C. Even at a higher C-rate of 1 C, more than 600 mAh g−1 of discharge capacity could be delivered after 500 cycles. The efficient polysulfide adsorption of TiO2 microboxes demonstrated by visualized adsorption test and UV–vis measurement as well as the mesoporous hollow feature was responsible for the large discharge capacity, excellent capacity retention and decent rate capability. | battery |
Vote functions are important devices for providing a ‘big picture’ of developments in electoral politics. However, the limited degrees of freedom upon which they are typically based mean that vote functions are rarely able to properly discriminate between competing accounts of electoral outcomes. They also fail adequately to capture the impact of ‘events’ or to recognise the extent to which the context of electoral competition can vary over time. Popularity functions that restrict themselves to relatively limited periods of time are capable of addressing all of these concerns: they enjoy more degrees of freedom, can take full account of the impact of ‘events’, and can focus on very specific electoral periods. Interestingly, however, Lewis-Beck’s vote function for post-war British politics contains variables that are very similar to those in a popularity function that was developed for the most recent (2001) British general election. In the British context, vote and popularity functions seem to provide quite similar accounts of the main drivers of party support. The advantage of both approaches is that they provide clearly specified, unambiguous—and falsifiable—accounts of the phenomenon under investigation. | non-battery |
Peaking power plants are used to provide power during periods that have both high load and limited supply from intermittent renewable energy. Wind power is intermittent and does not always provide electricity during periods of maximum demand. Despite this, it has grown to produce a significant portion of the electricity in some jurisdictions. Electricity systems require firm capacity that operate when called upon. Fossil fuel peaking plants are costly, providing a fraction of the annual energy at a great cost, but ensure system reliability. Utilizing storage systems to provide these services during peak times could allow integration of higher penetrations of renewable energies. Prince Edward Island, Canada has over 40% of its load produced by wind power but requires diesel generators during high load and low wind periods. The diesel generators ensure that the submarine cables are not overloaded and provide on-island power during other curtailments. The 1 MW/2 MWh storage system provided energy and capacity from December 2015 to March 2016 and was paid for these services by their local utility. The payment only covered 9% of the costs due to the high capital cost and short life expectancy of their storage system. | battery |
Oxygen reduction reaction (ORR) and evolution reaction (OER) are one pair of the most important electrochemical reactions associated with energy conversion and storage technologies, such as fuel cells, metal–air batteries, and water electrolyzers. However, the sluggish ORR and OER requires a significantly large quantity of precious metals (e.g., Pt or Ir) to enhance reaction activity and durability. Highly active and robust nonprecious metal catalysts (NPMCs) are desperately required to address the cost and durability issues. Among NPMC formulations studied, carbon-based catalysts hold the greatest promise to replace these precious metals in the future due to their low-cost, extremely high surface area, excellent mechanical and electrical properties, sufficient stability under harsh environments, and high functionality. In particular, nitrogen-doped carbon nanocomposites, which were prepared from “metal-free” N–C formulations and transition metals-derived M–N–C (M=Fe or Co), have demonstrated remarkably improved catalytic activity and stability in alkaline and acidic electrolytes. In this review, based on the recent progress in the field, we aim to provide an overview for both types of carbon catalysts in terms of catalyst synthesis, structure/morphology, and catalytic activity and durability enhancement. We primarily focus on elucidation of synthesis–structure–activity correlations obtained from synthesis and extensive characterization, thereby providing guidance for rational design of advanced catalysts for the ORR. Additionally, a hybrid concept of using highly ORR active carbon nanocomposites to support Pt nanoparticles was highlighted with an aim to enhance catalytic performance and reduce required precious metal loading. Beyond the ORR, opportunities and challenges of ORR/OER bifunctional carbon composite catalysts were outlined. Perspectives on these carbon-based catalysts, future approaches, and possible pathways to address current remaining challenges are also discussed. | battery |
Car manufactures have announced the launch in coming months of vehicles with reduced emissions due to the introduction of new functions like stop–start and regenerative braking. Initial performance request of automotive lead-acid batteries are becoming more and more demanding and, in addition to this, cycle life with new accelerated ageing profiles are being proposed in order to determine the influence of the new functions on the expected battery life. This paper will show how different lead-acid battery technologies comply with these new demands, from an improved version of the conventional flooded SLI battery to the high performance of spiral wound valve-regulated lead-acid (VRLA) battery. Different approaches have been studied for improving conventional flooded batteries, i.e., either by the addition of new additives for reducing electrolyte stratification or by optimisation of the battery design to extend cycling life in partial state of charge conditions. With respect to VRLA technology, two different battery designs have been compared. Spiral wound design combines excellent power capability and cycle life under different depth of discharge (DoD) cycling conditions, but flat plate design outperform the latter in energy density due to better utilization of the space available in a prismatic enclosure. This latter design is more adequate for high end class vehicles with high electrical energy demand, whereas spiral wound is better suited for high power/long life demand of commercial vehicle. High temperature behaviour (75°C) is rather poor for both designs due to water loss, and then VRLA batteries should preferably be located out of the engine compartment. | battery |
In this report, graphene nanosheets (GNS)/nickel sulfide (NiS) based material for high-performance supercapacitor is prepared by “dip and dry” and electrodeposition methods. Commercial flexible make-up cottons (MCs) are chose as skeletons to construct homogeneous three-dimensional (3D) interconnected graphene-wrapped macro-networks, which can support structures for high loading of active electrode materials and facilitate the access of electrolytes to active electrode materials. The hybrid GNS/NiS based MCs (denoted as MCs@GNS@NiS) electrode yields relatively high specific capacitance of 775 F g−1 at a charge/discharge specific current of 0.5 A g−1 and good capacitance retention of 88.1% after 1000 cycles at 2 A g−1. Furthermore, the MCs@GNS@NiS electrode delivers a high energy density of 11.2 Wh kg−1 at even a high power density of 1008 W kg−1. Therefore, such low-cost and high-performance energy MCs based on GNS/NiS hierarchical nanostructures offer great promise in large-scale energy storage device applications. | battery |
Cognitive abilities are complex human traits influenced by genetic factors. Brain-derived neurotrophic factor (BDNF), a unique polypeptide growth factor, has an influence on the differentiation and survival of neurons in the nervous system. A single-nucleotide polymorphism (rs6265) in the human gene, resulting in a valine to methionine substitution in the pro-BDNF protein, was thought to associate with psychiatric disorders and might play roles in the individual difference of cognitive abilities. However, the specific roles of the gene in cognition remain unclear. To investigate the relationships between the substitution and cognitive abilities, a healthy population-based study and the PCR-SSCP method were performed. The results showed the substitution was associated with digital working memory (p = 0.02) and spatial localization (p = 0.03), but not with inhibition, shifting, updating, visuo-spatial working memory, long-term memory, and others (p > 0.05) among the compared genotype groups analyzed by general linear model. On the other hand, the participants with BDNFGG had higher average performance in digital working memory and spatial localization than the ones with BDNFAA. The findings of the present work implied that the variation in BDNF might play positive roles in human digital working memory and spatial localization.
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The development of novel sodium-ion batteries has been hindered by the lack of ideal anode materials. Herein, we report both experimental and theoretical assessment of layered MoSe2 nanoplates as the anode materials. The MoSe2 nanoplates are successfully synthesized by a facile thermal-decomposition process. As the anode, the MoSe2 nanoplates are capable of delivering the initial discharge and charge capacities of 513 and 440 mAh g−1 at the current of 0.1C in a voltage of 0.1–3 V, respectively. The analysis of Ex-situ XRD patterns reveals that there is no slippage between layers and the change of coordination of molybdenum when the MoSe2 electrode is discharged to 0.6 V and conversion reactions during the following discharge/charge process are also demonstrated. In addition, the electronic structure, Na ions transport and conductivity are investigated by first-principles calculation. A quasi-2D energy favorable trajectory is proposed to illustrate the sodium ion vacancy-hopping migration mechanism form octahedron to tetrahedron in MoSe2 lattice. The results suggest great potential of MoSe2 as an anode material for Na ion batteries. | battery |
Finding the optimal balance between electricity demand and production constrained to economic and comfort variables requires intelligent decision and control. This article addresses the formulation of three models that optimize control of a heating, ventilation and air conditioning (HVAC) system in an experimental room, which are coupled with two thermal models of the indoor temperature. Electricity is supplied by the grid and a photovoltaic system with batteries. The primary objective is to maximize users comfort while minimizing cost constrained to: thermal comfort; variable electricity price; and available electricity in batteries that are charged by a PV system. Three models are developed: (i) dynamic programming with simplified thermal model (STM), (ii) genetic algorithm with STM, and (iii) genetic algorithm with EnergyPlus. The genetic algorithm model that uses EnergyPlus to simulate indoor temperature generally achieves higher convergence to the optimal value, which also is the one that uses more electricity from the PV system to operate the HVAC. The dynamic programming performs better than the genetic algorithm (both coupled with STM). However, it is limited by the fact that uses STM, which is a less accurate model to simulate indoor temperature especially because it is not considering thermal inertia. | non-battery |
Cigarette smoke condensates (CSCs) are complex mixed compounds that contain both direct and indirect mutagens/carcinogens. To detect genotoxicity of CSCs in vitro, a combination of various enzymes (e.g. activation and detoxification enzymes) called S9 is usually added. However, as S9 may induce cytotoxicity in target cells, it is unclear whether the addition of S9 can impact CSC-induced toxicity. Here, differences in cytogenotoxicity between CSCs in the presence or absence of S9 were studied using three in vitro assays (neutral red uptake assay, comet assay, and TCR gene mutation test) in human peripheral lymphocytes, which were exposed to CSCs at doses of 25, 50, 75, 100 and 125μg/ml for 4h. Assay results showed that both CSCs+S9 or CSCs−S9 could induce a dose-dependent elevation of cytogenotoxic effects in human lymphocytes with some differences between the two groups. The cytogenotoxicity induced by CSCs−S9 was significantly higher than that induced by CSCs+S9 in all three assays. The comet and NRU assays revealed that a dose–response relationship of cytogenotoxicity induced by CSCs+S9 was less typical than that induced by CSCs−S9, possibly due to specific cytogenotoxic agents in CSCs and enzymes contained in the S9 mixture. Thus, the three in vitro assays used in the present study are suitable for detecting cytogenotoxic effects in human lymphocytes induced by CSCs. Furthermore, the cytogenotoxicity induced by both CSCs+S9 and CSCs−S9 should be measured simultaneously when assessing and comparing the biological activity of different CSCs. | non-battery |
Thanks to today’s modern imaging examination techniques and especially to the common use of intracranial electrodes for localizing seizure foci, more and more patients with partial epilepsy can be treated microsurgically. The results of such neurosurgical therapies are very good, particularly in mesial temporal lobe epilepsy. In recent years, good results (60–70% seizure freedom) have also been achieved in extratemporal epilepsy surgery, so that such procedures can now be recommended for carefully selected patients. In this review, presurgical evaluations and the different surgical approaches are presented.
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There is much confusion and uncertainty in the literature concerning the useable power capability of batteries and ultracapacitors (electrochemical capacitors) for various applications. Clarification of this confusion is one of the primary objectives of this paper. The three approaches most often applied to determine the power capability of devices are (1) matched impedance power, (2) the min/max method of the USABC, and (3) the pulse energy efficiency approach used at UC Davis. It has been found that widely different power capability for batteries and ultracapacitors can be inferred using these approaches even when the resistance and open-circuit voltage are accurately known. In general, the values obtained using the energy efficiency method for EF =90–95% are much lower than the other two methods which yield values corresponding to efficiencies of 70–75%. For plug-in hybrid and battery electric vehicle applications, the maximum useable power density for a lithium-ion battery can be higher than that corresponding to 95% efficiency because the peak power of the driveline is used less frequently and consequently charge/discharge efficiently is less important. For these applications, the useable power density of the batteries can be closer to the useable power density of ultracapacitors. In all cases, it is essential that a careful and appropriate measurement is made of the resistance of the devices and the comparisons of the useable power capability be made in a way appropriate for the application for which the devices are to be used. | battery |
Chlorhexidine is among the most used biocides in Europe, however its toxicity to aquatic organisms is scarcely known. The main objective of this study was to assess the lethal and sub lethal effects of chlorhexidine digluconate (ChD) on four aquatic model organisms: the bacteria Vibrio fischeri, the algae Pseudokirchneriella subcapitata, the crustacean Daphnia magna and the embryos of the fish Danio rerio. ChD was very toxic to algae and crustaceans, with a 72 h-EC50 of 62.2 μg/l and a 48 h-EC50 of 45.0 μg/l, respectively. Toxicity to fish embryos and the bacteria was lower, with a 96 h-EC50 of 804.0 μg/l and a 15 min-EC50 of 1,694.0 μg/l, respectively. Concerning sub lethal effects on D. magna (feeding inhibition) a 6 h-EC50 of 503.7 μg/l was obtained. In fish, ChD caused developmental abnormalities, namely alterations in the amniotic fluid (48 h-EC20 of 753.6 μg/l) and early hatching. Moreover, enzymatic biomarkers on fish embryos showed an induction of cholinesterase activity in all ChD tested concentrations (80–900 μg/l). The catalase activity was also induced at the highest concentration tested (900 μg/l) whereas no changes were observed for glutathione-S-transferase and lactate dehydrogenase activities. The toxicity of ChD to the algae and crustacean raises concerns about its potential effects in aquatic food webs, since these organisms are in the base of trophic chains, and highlights the need for further studies on ChD toxicity to aquatic organisms.
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Medication use is a potentially modifiable risk factor for falling; psychotropic and cardiovascular drugs have been indicated as main drug groups that increase fall risk. However, evidence is mainly based on studies that recorded falls retrospectively and/or did not determine medication use at the time of the fall. Therefore, we investigated the associations indicated in the literature between medication use and falls, using prospectively recorded falls and medication use determined at the time of the fall. | non-battery |
The spinel LiMn1.94MO4 (M = Mn0.06, Mg0.06, Si0.06, (Mg0.03Si0.03)) compounds are successfully synthesized by citric acid-assisted sol–gel method. The crystal structures and morphologies of synthesized compounds are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. All the compounds possess the cubic spinel structure of LiMn2O4 with space group of Fd-3m. The electrochemical properties of synthesized compounds are investigated by galvanostatic charge-discharge test, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results show that the Si-doping can increase the discharge capacity of LiMn2O4 due to the more expanded and regular MnO6 octahedra. In particular, for the LiMn1.94Mg0.03Si0.03O4 compound, the addition of Si4+ ions can make up for the shortage of Mg-doping in term of the discharge capacity. As a result, the Mg2+ and Si4+ co-doping has the effect of synergistic enhancement, which can make full use of the respective advantages of Mg-doping and Si-doping. The optimal LiMn1.94Mg0.03Si0.03O4 can deliver the initial discharge capacity of 128.3 mAh g−1 with good capacity retention of 92.8% after 100 cycles at 0.5 C in the voltage range of 3.20–4.35 V. Compared with the undoped LiMn2O4, the co-doped compound also presents superior rate performance, especially the capacity recovery performance. | battery |
Energy harvesting and storage devices, including lithium-ion batteries (LIBs), supercapacitors (SCs), nanogenerators (NGs), biofuel cells (BFCs), photodetectors (PDs), and solar cells, play a vital role in human daily life due to the possibility of replacing conventional energy from fossil fuels. However, these isolated devices only have limited performance and/or sole applicability, and cannot provide enough energy for application with long-term run and the ever-changing working positions. This suggests that it is urgent to develop the fine self-powered systems to meet the growing demand of energy for long-term use in different environment scenes. Developing integrated power pack, combining energy harvesting and storage, is an effective path to obtain a small size, light weight, high density and high reliability energy system. In this review, eight types of multifunctional integrated devices, such as LIB&SC, LIB&NG, BFC&NG, PD&BFC, SC&PD, SC&solar cells, NG&SC&solar cell, and LIB&solar cells, for energy harvesting and storage are reviewed in a broad sense, and a comprehensive summary of the recent development trends and highlights in the integrated device fields is given. Finally, the challenges and future outlooks for their successful commercialization are featured based on the recent advances and important findings. | battery |
In an endeavour to improve not only the thermal shrinkage but also the electrochemical performance of separators in lithium-ion batteries, a novel composite separator is developed, i.e., a close-packed SiO2/poly(methyl methacrylate) (PMMA) binary nanoparticles-coated polyethylene (PE) separator. The introduction of SiO2 nanoparticles to the coating layer effectively suppresses thermal shrinkage of the composite separator. In contrast to a SiO2/PMMA coating layer having a film-shaped PMMA binder, the SiO2/PMMA binary nanoparticle coating layer employs PMMA particles as a binder. As a consequence, a highly porous structure, i.e., well-connected interstitial voids, is formed between the binary SiO2 and PMMA nanoparticles. The unique porous morphology allows favourable liquid electrolyte wettability and facile ionic conduction, which play a crucial role in improving cell performance such as the discharge capacity and the C-rate capability of the composite separator. | battery |
The use of latent heat thermal energy storage for thermally buffering vehicle systems is reviewed. Vehicle systems with transient thermal profiles are classified according to operating temperatures in the range of 0–800°C. Thermal conditions of those applications are examined relative to their impact on thermal buffer requirements, and prior phase change thermal enhancement studies for these applications are discussed. In addition a comprehensive overview of phase change materials covering the relevant operating range is given, including selection criteria and a detailed list of over 700 candidate materials from a number of material classes. Promising material candidates are identified for each vehicle system based on system temperature, specific and volumetric latent heat, and thermal conductivity. Based on the results of previous thermal load leveling efforts, there is the potential for making significant improvements in both emissions reduction and overall energy efficiency by further exploration of PCM thermal buffering on vehicles. Recommendations are made for further material characterization, with focus on the need for improved data for metallic and solid-state phase change materials for high energy density applications. | battery |
In order to develop the new anode materials for Al/air batteries, electrochemical properties of pure aluminium (99.999 %), technical grade aluminium (99.8 %) and the alloys with indium and tin, i.e. Al—0.1 % In, Al—0.2 % Sn and Al—0.1 % In—0.2 % Sn have been investigated in 2 mol dm−3 NaCl solution. The aluminium materials were polarized anodically in the range 20–100 mA cm−2 for a 30 min period. During the anodic polarization variation in potential was recorded as a function of time and the simultaneous hydrogen evolution was measured. The rate of hydrogen evolution reaction was found to increase with increasing anodic polarization which is characteristic of the negative difference effect. The additional information concerning the corrosion behaviour of the tested materials was provided by light microscope imaging. The results show that the examined technical grade aluminium alloys could serve as suitable anodes for Al/air batteries containing sodium chloride electrolyte; with Al–In exhibiting the most remarkable characteristics. The addition of In as alloying component to aluminium reduces electrode polarization, decreases hydrogen evolution rate and increases the anode efficiency. | battery |
Potassium-ion batteries (KIBs) have attracted intensive attention in recent years due to the resource-abundance and low cost of potassium. Here, for the first time, SnO 2 nanosheets grown on stainless steel mesh (SnO 2 /SSM) were used as a novel binder free anode for KIBs. A high capacity of 351mAhg−1 is achieved after 100cycles at current density of 50mAg−1. Even more, a high capacity of 128mAhg−1 can be obtained at 1000mAg−1 after 200cycles. These good electrochemical performances are mainly due to the large surface area of SnO 2 nanosheets and the roles of current collector and stable conductive skeleton SSM played. | battery |
The reduction of oxygen was studied in 0.1M KCl at 70°C using the rotating disk electrode (RDE) technique on platinum and electrodeposited ZnO thin film electrodes deposited on platinum substrates. In the absence of Zn2+ ions in solution, a Tafel slope of 139mVdec−1 was obtained, a value close to that measured on bare platinum electrode (133mVdec−1) and ascribed to the limitation of the reaction rate by the first electron transfer. The main difference between the noble metal and the oxide electrode was a shift of the curves towards more negative potentials. In the presence of Zn2+ ions, the current density decreased significantly and the Tafel slope was measured at 282mVdec−1 showing that the electrode was partially blocked by zinc oxide formation reaction intermediates. | battery |
Application of municipal solid waste and sewage sludge to supplement soil is an age-old agronomic practice due to its rich organic contents. These soil-supplements also contain significant amount of non-essential heavy metals, posing threat to crop yield and human health. The present study aims to compare the phytotoxicity of the heavy metals and potential dietary toxicity of some selected vegetables grown in soil supplemented with municipal solid waste and sewage sludge. To assess the phytotoxicity of the supplements, plants were grown in three different sets; (1) Hoagland’s nutrient media [as control] (2) municipal solid waste and (3) sewage sludge soil mix. To study the phytotoxic markers, photosynthetic pigments, proline, protein content and antioxidant enzyme activities were measured and metal content of the vegetables were measured to estimate the potential dietary toxicity. It was observed from the study that vegetables grown in supplemented soils showed reduced chlorophyll and protein content while carotenoid, proline and antioxidative enzymes showed enhanced activity. In both the supplemented soil, it was observed that cadmium was present above the maximum allowable limits, amount of lead was marginal and that of chromium was below the level. It was observed that the two leafy vegetables, i.e., Lagenaria sp. and Cucurbita sp. accumulated more lead in their aerial parts, Lagenaria grown in sewage sludge supplemented soil also accumulated significant amount of cadmium in the aerial parts. Edible parts of Raphanus and maize grains also accumulated considerable amount of cadmium, which were above the value of daily tolerable limits.
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The growing concern about the environment, associated with the continuous increase in the production of electronic equipment, such as computers, cell phones, mobile devices and consequently batteries, has induced research to develop new technologies to recycle the huge numbers of spent batteries generated in the last few years. The amount of spent NiMH batteries will tend to grow continually over the next few years. These batteries have in their chemical composition, valuable metals such as Ni, Co and rare earths. In the first stage of this work a characterization of NiMH batteries was done. Batteries from different brands and models were disembled and their components were characterized in relation to their chemical composition and main phases. In a second stage of this work, a sample of spent NiMH batteries was milled and the polymeric and metallic fractions were magnetically separated. The results obtained demonstrate that the recycling study, aimed at the recovery of Ni, Co and rare earths, is viable due to the great amount of these metals that are present batteries. It also demonstrates that magnetic separation is a very efficient process to recovery nickel alloys. However the effects of cadmium contamination (originating from fake batteries) will cause the recycling processes to be re-evaluated. | battery |
Carbon aerogel, carbon black and graphite were used to analyze the influence of conductive filler on the impedance behaviors of activated carbon based electric double layer capacitors (EDLCs). According to the electrochemical impedance spectrum (EIS) data, a new equivalent circuit model was proposed involving the kinetic characteristics of ion diffusion, furthermore, Marquardt fit procedure was applied to the EIS data to obtain the model parameter values. The results indicated that carbon aerogel could significantly decrease the resistance of EDLCs by increasing the diffusion coefficient of ions within electrodes and decreasing the interface resistance because of its suitable particle size, mesoporous structures and finely-branched particle performance. | battery |
The electrochemical behavior and the electrodeposition of dysprosium (Dy) in phosphonium-cation-based ionic liquid were investigated in this study. A new group of the room-temperature ionic liquids (RTILs) based on phosphonium cations with bis(trifluoromethylsulfonyl)amide anions was applied as novel electrolytic solutions. The cyclic voltammetric measurements resulted in one step reduction of the trivalent dysprosium ion in phosphonium-cation-based ionic liquid. On the other hand, no anodic peak ascribed to the oxidation of dysprosium metal was observed in this electroanalytical study. The diffusion coefficient and the activation energy for diffusion of the trivalent Dy complex in IL were estimated using semi-integral analysis, because it is important to analyze the diffusion properties to recover Dy through electrowinning methods. The diffusion coefficient of Dy(III) which was calculated to be 2.0 × 10−12 m2 s−1 at 25 °C, closed to that of the trivalent lanthanoid ion such as Eu(III) and Sm(III) in phosphonium-cation-based ionic liquid. In addition, the activation energy for diffusion was estimated to be 65 kJ mol−1 (0.5 M) and 49 kJ mol−1 (0.075 M). The estimated activation energy for diffusion was affected by the concentration of the electrolytic solution, since the RTILs had relatively strong electrostatic interactions between the metal cations and the solvent anions. Furthermore, the electrodeposition of Dy in phosphonium-cation-based IL was carried out using a two-electrode system constructed with a copper plate cathode and dysprosium metal anode. Energy dispersive X-ray analysis of electrodeposits showed a sharply peaked spectrum corresponding to the characteristic X-ray lines of Dy. In addition, the obtained Dy, with the exception of the surface layer, was confirmed to be in the metallic electronic state by X-ray photoelectron spectroscopy. | battery |
Hydrogen injection into and extraction from hydride-forming electrodes has been routinely investigated under the assumption that the electrode is homogeneous in structure and hydrogen transport through such electrodes is purely controlled by hydrogen diffusion. However, various kinds of abnormal behaviours in hydrogen transport, which could hardly be explained in terms of the diffusion-control model, have been quite frequently reported by many researchers. This review provides a comprehensive survey of the anomalous behaviours of hydrogen transport observed in such hydride-forming electrodes as Pd and metal-hydrides, with particular emphasis on hydrogen extraction under the impermeable boundary conditions during the potentiostatic current transient measurement involving the potential stepping. After a brief discourse on the conventional diffusion-control model, the topics related to the boundary conditions at the electrode surface during hydrogen extraction are extensively reviewed. In particular, it is shown that the diffusion-controlled constraint should be no longer valid at the electrode surface for hydrogen extraction in case hydrogen diffusion is influenced by either the interfacial charge transfer reaction or the hydrogen transfer reaction between adsorbed state on the electrode surface and absorbed state at the electrode sub-surface. Subsequently, the atypical behaviours of current transient due to hydrogen diffusion in the presence of traps and in the coexistence of two hydride phases are treated in detail. Each of the hydrogen extraction models suggested is discussed with the aid of the anodic current transients numerically calculated based upon the theoretical electrode potential curve, and then it is exemplified by hydrogen extraction from Pd and metal-hydrides in aqueous solutions. | battery |
A highly porous three-dimensional Ni–Sn alloy foam is fabricated by electro-deposition accompanied by hydrogen evolution reaction. This foam can evolve into porous and dendritic metal alloy structures. These Sn-based electrodes have been evaluated for use as anodes in lithium-ion batteries. Dendritic Ni50Sn50 alloy foam exhibits high electrochemical capacity and excellent cycle stability during charge–discharge processes. The nickel in a Ni–Sn alloy does not break off during the volume expansion/contraction sequence in battery operation cycles and supports the Sn remaining on the anodes. The voids in the tube-like porous Ni–Sn morphology enhance the mass transfer of Li+ ions and act as mechanical bumpers during the charge–discharge processes. | battery |
European national, regional, and local authorities have started to take action to make public bus transport services more effective and less polluting. Some see the possibility to move beyond a narrow focus on efficiency or carbon dioxide reductions towards an integrated sustainability perspective. This paper uses this perspective to build and test a new assessment approach that should enhance decisions on bus transport powertrains and energy carriers for Swedish medium-sized cities. The study suggests that a superiority of electric powertrains is revealed if a traditional economic analysis is integrated with a strategic sustainability perspective. | non-battery |
ABSTRACT Polymer electrolytes (PEs) have served as the focus of intensive research as new ion-conducting materials, especially for lithium battery applications. A new strategy to develop fast lithium-conducting PEs is reported here. The thermal, ionic transport, and electrochemical properties of polymer solutions in a glyme-Li salt solvate ionic liquid, [Li(G4)1][TFSA], composed of an equimolar mixture of lithium bis(trifluoromethanesulfonyl) amide (Li[TFSA]) and tetraglyme (G4), were characterized. Poly(ethylene oxide) (PEO), poly(methyl methacrylate) (PMMA), and poly(butyl acrylate) (PBA) were combined with [Li(G4)1][TFSA] in order to explore the effects of polymer structure on the properties. The self-diffusion coefficient ratio of the glyme and Li+ ions (D G/D Li) was investigated to evaluate the stability of the complex (solvate) cations. The D G/D Li values suggested that the [Li(G4)1]+ complex cations underwent a ligand exchange reaction between G4 and PEO in the PEO-based solution, whereas the cations remained stable (D G/D Li =1) in the PMMA- and PBA-based solutions. The robustness of the [Li(G4)1]+ complex cations in the PMMA- and PBA-based solutions was reflected in high weight-loss temperature, greater Li transference number, and high oxidative stability. Owing to the lower glass transition temperature and low affinity towards Li+ ions, the PBA-based solutions yielded superior lithium transport properties (ionic conductivity of 10−4∼10−3 Scm−1 and Li transference number as high as 0.5) among the investigated polymer solutions. | battery |
Layered Li1+x Ni0.30Co0.30Mn0.40O2 (x =0, 0.05, 0.10, 0.15) materials have been synthesized using citric acid assisted sol–gel method. The materials with excess lithium showed distinct differences in the structure and the charge and discharge characteristics. The rate capability tests were performed and compared on Li1+x Ni0.30Co0.30Mn0.40O2 (x =0, 0.05, 0.10, 0.15) cathode materials. Among these materials, Li1.10Ni0.30Co0.30Mn0.40O2 cathode demonstrated higher discharge capacity than that of the other cathodes. Upon extended cycling at 1C and 8C, Li1.10Ni0.30Co0.30Mn0.40O2 showed better capacity retention when compared to other materials with different lithium content. Li1.10Ni0.30Co0.30Mn0.40O2 exhibited 93 and 90% capacity retention where as Li1.05Ni0.30Co0.30Mn0.40O2, Li1.15Ni0.30Co0.30Mn0.40O2, and Li1.00Ni0.30Co0.30Mn0.40O2 exhibited only 84, 71, and 63% (at 1C), and 79, 66 and 40% (at 10C) capacity retention, respectively, after 40 cycles. The enhanced high rate cycleability of Li1.10Ni0.30Co0.30Mn0.40O2 cathode is attributed to the improved structural stability due to the formation of appropriate amount of Li2MnO3-like domains in the transition metal layer and decreased Li/Ni disorder (i.e., Ni content in the Li layer). | battery |
We prepared synthetic porous carbons with a three-dimensional interconnected network of ultramicroporous particles; by adjusting the synthesis parameters the size of these particles was systematically varied from 13nm to 1.4μm. Cyclic voltammetry measurements using a cavity microelectrode (CME) were performed in different chloric aqueous electrolyte solutions. The CME allows for very fast measurements (up to 10V/s) of carbon powders without the need of a binder or conductivity additive. Therewith we were able to investigate the accessibility of the ultramicropores and kinetics of the electrochemical double-layer (EDL) charging as a function of particle, inter-particular pore, effective ion and micropore size. We found, that the alkaline cations K+, Na+, Li+ and the anion Cl− can enter micropores down to a size of 0.4nm at slow charging rates independent of the particle size. However, the accessibility is decreased due to kinetic limitations for the cations Na+ and Li+ at higher scan rates, which was not observed for the smaller K+ ion. A simple model is presented, which explains the influence of the particle, inter-particular pore and micropore size on the kinetics of double-layer charging. This model suggests that first of all the carbon particle size is not a limiting factor for fast EDL charging as long as its size is smaller than a few hundred nanometers and secondly inter-particular pores with a size in the range of the particle size or larger are crucial for high-rate applications. | battery |
Past studies on the factor validity of the Trait subscale of the Spielberger’s State-Trait Anxiety Inventory (STAI-T) do unanimously agree on its structure. In fact, researchers are still debating whether the STAI-T is unidimensional or multidimensional. Our aim was to clarify what the STAI-T measures. The STAI-T, the Beck Depression Inventory–II, the Teate Depression Inventory, and the Beck Anxiety Inventory were administered to 1124 psychiatric outpatients and to 877 healthy subjects. A confirmatory factor analysis was performed in order to compare various models in the literature. The internal consistency and convergent and discriminant validity of the STAI-T as well as its factorial subscales were assessed. The one-construct two-method (i.e., the STAI-T measures one substantive anxiety construct plus artifacts due to negative–positive item polarity) and the bifactor (i.e., the STAI-T comprises two first-order specific factors [“Anxiety” and “Depression”] and one first-order general factor) models were the best-fitting solutions for the STAI–T in both the clinical and nonclinical samples. The STAI–T total score correlated more strongly with measures of depression than with a concurrent measure of anxiety. The STAI-T should be considered a measure of general negative affect, including specific aspects of cognitive anxiety and depression together.
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Li-rich layered oxide Li1.2Co0.13Ni0.13Mn0.54O2 has been successfully re-synthesized using the ascorbic acid leaching solution of spent lithium-ion batteries as the raw materials. A combination of oxalic acid co-precipitation, hydrothermal and calcination processes was applied to synthesize this material. For comparison, a fresh sample with the same composition has been also synthesized from the commercial raw materials using the same method. X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and electrochemical measurements are carried out to characterize these samples. XRD results indicate that both samples have the layered α-NaFeO2 structures with a space group of R 3 ¯ m. No other crystalline phase was detected by XRD. The electrochemical results show that the re-synthesized and fresh-synthesized sample can deliver discharge capacities as high as 258.8 and 264.2 mAh g−1 at the first cycle, respectively. After 50 cycles, discharge capacities of 225.1 and 228 mAh g−1 can be obtained with capacity retention of 87.0 and 86.3%, respectively. This study suggests that the leaching solution from spent lithium ion batteries can be recycled to synthesize Li-rich cathode materials with good electrochemical performance. | battery |
Lithium-rich layered oxides (LLOs) are considered promising cathode materials for lithium-ion batteries because of their high reversible capacity, which is attributed to the exploitation of the novel anionic redox in addition to the conventional cationic redox process. Transition metal (TM) migration, which is known to be the main cause of the voltage decay in LLOs, is now understood to also be the critical factor triggering anionic redox, although this origin is still under debate. A better understanding of the specific TM migration behavior and its effect during charge/discharge would thus enable further development of this class of materials. Herein, we demonstrate that the unique TM migration during charge/discharge significantly alters the lithium diffusion mechanism/kinetics of LLO cathodes. We present clear evidence of the much more sluggish lithium diffusion occurring during discharge (lithiation) than during charge (de-lithiation), which contrasts with the traditional lithium diffusion model based on simple topotactic lithium intercalation/deintercalation in the layered framework. The reversible but asymmetric TM migration in the structure, which originates from the non-equivalent local environments around the TM during the charge and discharge processes, is shown to affect the lithium mobility. This correlation between TM migration and lithium mobility led us to propose a new lithium diffusion model for layered structures and suggests the importance of considering TM migration in designing new LLO cathode materials.
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The dispersion properties of carbon black (CB) slurries as well as the accompanying electrochemical properties of Li(Ni1/3Co1/3Mn1/3)O2 (NCM) electrodes were investigated by controlling the amine value of polyurethane-based dispersants. The increase in amine value of dispersants leads to an increase in adsorption level on CB surface due to a strong acid/base interaction between dispersants and CB particles, providing the improvement of steric repulsion between particles at the solid–liquid interface. This results in the enhancement of the dispersion stability of CB and the related microstructure of the electrodes. Electrochemical experiments indicated that the rate capabilities and cycle performance of the electrodes are in good agreement with dispersion properties of CB slurries. However, it was found that the excessive addition of the dispersant was deleterious to electrochemical properties because the non-adsorbed dispersants act as an electronic conduction barrier between solid phases. Therefore, it is suggested that the amine value of dispersant and tailored amount of dispersant addition can be key roles for obtaining the optimized dispersion stability of CB and the corresponding excellent electrochemical properties of the cathode. | battery |
Summary This paper explores households’ coping strategies in rural South Africa, where HIV/AIDS morbidity and mortality are having profound effects on household resources. Older women’s pensions play a potentially crucial role in multi-generational households during crises and for day-to-day subsistence. We conducted semi-structured interviews with 30 elderly women from the MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt) fieldsite, who were eligible for the South African non-contributory pension. Although we stratified our sample by household mortality experience, the area’s high levels of migration, unemployment, and HIV/AIDS prevalence made our respondents’ pensions an important, regular, and reliable source of household-income regardless of their households’ mortality profile. | non-battery |
The level of functioning of individuals with autism spectrum disorder (ASD) varies widely. To better understand the neurobiological mechanism associated with high-functioning ASD, we studied the rare case of a female patient with an exceptional professional career in the highly competitive academic field of Mathematics. According to the Research Domain Criteria (RDoC) approach, which proposes to describe the basic dimensions of functioning by integrating different levels of information, we conducted four fMRI experiments targeting the (1) social processes domain (Theory of mind (ToM) and face matching), (2) positive valence domain (reward processing), and (3) cognitive domain (N-back). Patient’s data were compared to data of 14 healthy controls (HC). Additionally, we assessed the subjective experience of our case during the experiments. The patient showed increased response times during face matching and achieved a higher total gain in the Reward task, whereas her performance in N-back and ToM was similar to HC. Her brain function differed mainly in the positive valence and cognitive domains. During reward processing, she showed reduced activity in a left-hemispheric frontal network and cortical midline structures but increased connectivity within this network. During the working memory task patients’ brain activity and connectivity in left-hemispheric temporo-frontal regions were elevated. In the ToM task, activity in posterior cingulate cortex and temporo-parietal junction was reduced. We suggest that the high level of functioning in our patient is rather related to the effects in brain connectivity than to local cortical information processing and that subjective report provides a fruitful framework for interpretation.
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This paper reports the wireless Shape-Memory-Polymer actuator operated by external radio frequency magnetic fields and its application in a drug delivery device. The actuator is driven by a frequency-sensitive wireless resonant heater which is bonded directly to the Shape-Memory-Polymer and is activated only when the field frequency is tuned to the resonant frequency of heater. The heater is fabricated using a double-sided Cu-clad Polyimide with much simpler fabrication steps compared to previously reported methods. The actuation range of 140 μm as the tip opening distance is achieved at device temperature 44 °C in 30 s using 0.05 W RF power. A repeatability test shows that the actuator’s average maximum displacement is 110 μm and standard deviation of 12 μm. An experiment is conducted to demonstrate drug release with 5 μL of an acidic solution loaded in the reservoir and the device is immersed in DI water. The actuator is successfully operated in water through wireless activation. The acidic solution is released and diffused in water with an average release rate of 0.172 μL/min.
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Lithium-sulfur (Li-S) batteries have attracted extensive interest due to their higher theoretical energy density than the current commercial lithium-ion batteries. However, their practical application is largely hindered by the low sulfur utilization and poor cycling stability. Restraining the shuttle effect and enhancing the electrochemical kinetics are important for developing high-performance Li-S batteries. Here we use carbon nanofibers (CNFs) supported manganese dioxide (MnO2) composite as a bifunctional coating on sulfur cathode for anchoring polysulfides and accelerating their redox reactions simultaneously. The CNFs/MnO2 composite supplies fast paths for electron transfer and ion diffusion, and greatly promotes the transformation processes of polysulfides to Li2S/Li2S2, leading to an enhanced electrochemical kinetics. The diffusion coefficient of lithium ion has been increased by 560%. As a result, the CNFs/MnO2 composite covered electrode exhibits an excellent cycling stability, its specific capacity maintains at about 600 mAh g−1 at 1C after 400 cycles, corresponding to a capacity decay as low as 0.063% per cycle, and the average coulombic efficiency reaches up to 99.66%. | battery |
An accurate state of charge (SoC) estimation of a traction battery in hybrid electric non-road vehicles, which possess higher dynamics and power densities than on-road vehicles, requires a precise battery cell terminal voltage model. This paper presents a novel methodology for non-linear system identification of battery cells to obtain precise battery models. The methodology comprises the architecture of local model networks (LMN) and optimal model based design of experiments (DoE). Three main novelties are proposed: 1) Optimal model based DoE, which aims to high dynamically excite the battery cells at load ranges frequently used in operation. 2) The integration of corresponding inputs in the LMN to regard the non-linearities SoC, relaxation, hysteresis as well as temperature effects. 3) Enhancements to the local linear model tree (LOLIMOT) construction algorithm, to achieve a physical appropriate interpretation of the LMN. The framework is applicable for different battery cell chemistries and different temperatures, and is real time capable, which is shown on an industrial PC. The accuracy of the obtained non-linear battery model is demonstrated on cells with different chemistries and temperatures. The results show significant improvement due to optimal experiment design and integration of the battery non-linearities within the LMN structure. | battery |
Amorphous nitrogen-doped carbon nanosheets was synthesized through thermal decomposition of ethylenediaminetetraacetic acid manganese disodium salt hydrate (C10H12N2O8MnNa2⿿2H2O). The as-synthesized nitrogen-doped carbon nanosheets were characterized by X-ray diffraction, scanning electron microscopy, transition electron microscopy and X-ray photoelectron spectroscopy. The N content of the as-synthesized carbon nanosheets could reach as high as 11.77at.%, with an especially high total of 7.94at.% pyridinic N pluspyrrolic N. When tested as anode material for lithium ion batteries, the optimized carbon nanosheets exhibited high capacity, excellent rate capability, and stable cyclability over 600 cycles. The specific capacity was still as high as 465.8mAhg⿿1 at 0.5C after 600 cycles,with a capacity decay from the 2nd cycle of 0.05% per cycle over 599 cycles. The excellent performance of C-600 is attributed to a synergistic effect of high surface area, numerous nanopores, high thermal stability, and low charge transfer resistance. | battery |
Nanosized MnO2 powders were grown using a green synthesis based on citrates via redox reaction between KMnO4 and natural reducing agents, i.e. lemon juice and peel extracts, without generating hazardous waste. X-ray diffraction (XRD) and Raman studies show that the samples grow as cryptomelane polymorph, α-MnO2, crystallized with the tetragonal cryptomelane structure. Both J-MnO2 prepared from lemon juice and P-MnO2 prepared from citrus peel consist of nanosized particles as observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Thermogravimetric analysis (TGA) confirms the typical thermal decomposition of MnO2 at temperatures of up to 500 °C. Improved electrochemical properties are obtained and discussed for P-MnO2, with a reversible capacity that reaches 160 mAh g−1 (initial capacity of 212 mAh g−1) at a current density of 10 mA g−1 and a good rate capability. | battery |