batterydata/paper-abstracts huggingface dataset:
SnS2/SnO2 composites were prepared in a microwave-assisted reaction of a mixture solution of SnCl4 and l-cysteine and were characterised by XRD, TEM, SEM and EDX. The influence of the mole ratio of SnCl4 to l-cysteine (l-cys) on the sample was investigated. It was found that using a microwave method, SnS2/SnO2 composites were formed, and SnS2/SnO2 nanoparticles were obtained when the mole ratio of SnCl4 to l-cysteine was 1:2. With higher contents of l-cys, when the mole ratio of SnCl4 to l-cys was 1:4, the products were nanosheets instead of nanoparticles. Electrochemical tests demonstrated that the SnS2/SnO2 composites with layer structure exhibited high reversible capacities and good cycling performances when used as anode materials of Li-ion batteries. When the mole ratio of SnCl4 to l-cys was 1:6, the initial reversible capacity of products was 593mAh/g, and the retention capacity that was maintained was over 88%. Besides, the retention capacity of products was still excellent at high current charge/discharge.
The composite powder of V2O5 and polypyrrole (V2O5/PPy) was prepared by chemical polymerization of pyrrole using V2O5 powder dispersed in an acidic solution as an oxidizing agent. The composites containing V2O5 in its amount ranging from 30 to 94 w/o were prepared from the preparation baths containing different amounts of dispersed V2O5 powder. Pellets of V2O5/PPy were prepared by pressing the composite powder without any binder. The prepared V2O5/PPy pellets exhibited charge–discharge curves characteristics of redox reaction of V2O5 (V2O5+xLi++e−=Li x V2O5 (0≤x≤1)), indicating that PPy worked well as binding material as well as conducting matrix. The effects of charge–discharge current densities and amounts of V2O5 in the composite were investigated. Cycle tests conducted by using the composite containing 91 w/o V2O5 revealed that 100 times repetition did not cause significant decrease in the capacity. The reaction scheme during the course of charge and discharge of the composite was investigated by its electrochemical behavior and elemental analysis.
The processes occurring consecutively during anodic oxidation of antimony in buffered phosphate solutions are followed by in situ ellipsometry. In the first stages of anodization, soluble species formation followed by formation of a highly hydrated film takes place. At higher potentials, the growth of a single layer of Sb2O3 anodic film occurs. Oxygen evolution occurring simultaneously with oxide growth is also detected. Surface chemical analysis by XPS allowed obtaining the chemical state and composition of the anodic antimony oxide films. The procedure followed in order to carry out the spectra deconvolution due to overlapping of O1s and Sb3d photoemission lines is discussed. The binding energy values obtained for O1s and Sb3d signals as well as the O/Sb atomic ratio indicates that the anodic film formed at low or high potentials is composed by Sb(III) species only. Hydration as well as phosphate ions incorporation into the film is also demonstrated.
A new self-plasticizing aliphatic polycarbonate comprising flexible alkyl and alkyl ether side groups was designed and synthesized from six-membered cyclic carbonate monomers with the aim of producing a material with high molecular flexibility (low T g) and concomitant high ionic conductivity when used as a polymer electrolyte. The T g of the novel polycarbonate was determined to be −49.4°C at a molecular weight of 34 400gmol−1, which is the lowest reported T g to date for a substituted poly(trimethylene carbonate). UV-crosslinked polymer electrolytes were produced based on this novel material together with LiTFSI salt and showed ionic conductivities in the range of 2×10−8 to 2×10−7 Scm−1 at room temperature and 1×10−6 to 1×10−5 Scm−1 at 100°C. The limited ionic conductivities of these electrolytes indicate that high molecular flexibility alone does not guarantee fast ion transport in solid polymer electrolytes and that other factors, such as the polarity of the polymer host material, will also influence the transport properties of the electrolyte.
Background Cognitive dysfunction is a common finding in individuals with multiple sclerosis at all ages. Cognitive impairment may drastically affect the life of younger patients with multiple sclerosis who are still undergoing education and schooling. Methods We carried out a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations to assess the published data on multiple sclerosis and cognition in pediatric or juvenile patients. Only articles presenting original data on patients with multiple sclerosis diagnosed before age 18 years of age were included. Results Thirty-two articles fulfilled the inclusion criteria for this systematic review. The conclusion from all articles was that cognitive dysfunction in multiple sclerosis starting before the age of 18 years is both significant and disruptive and must be routinely assessed. However, assessment methods were heterogeneous and often very expensive to perform, whereas proposals for treatment were virtually absent in the literature. Conclusion Cognitive dysfunction can be a significant symptom of multiple sclerosis of early onset, but its impact and management needs to be better assessed. A task force should be created to study and manage cognitive dysfunction in pediatric and juvenile multiple sclerosis.
Heart failure is a leading cause of death in human populations, and as people live longer, it is becoming an increasingly prominent problem. Because of the insufficient numbers of donor hearts, physicians and engineers are turning to mechanical circulatory support in the form of ventricular assist devices (VADs). Their clinical performance and increasing availability of various types, sizes, and functions are increasing VAD recognition. However, for any implantable medical device, especially one that is life supporting, performance and safety must be evaluated both pre- and postmarket. It has been demonstrated that specific pathology analysis can provide unique and important information to augment the evaluation of performance and safety. To help ensure the safety and efficacy of a device, we propose that regulatory agencies include pathology analysis by experienced, independent pathologists with relevant expertise as an integral component of device submissions. We believe that this analysis should include both gross and microscopic components and, when warranted, supplementary data obtained through radiography, electron microscopy, or both. The pathology data acquired through these analyses should be correlated with clinical data to yield a more thorough data set for submission to the governing regulatory body. Submitting this coordinated analysis of data will demonstrate to regulatory agencies (United States Food and Drug Administration, Therapeutic Goods Administration, Brazilian Health Surveillance Agency, etc.) that the device manufacturer shares their objective: making medical devices as safe and effective as possible. Summary This review of ventricular assist devices introduces a recommended protocol for pathology evaluations of devices from organizations or researchers seeking approval by a governing regulatory agency.
Layered nickel sulfide (NS)-reduced graphene oxide (RGO) composites are prepared via a simple microwave-assisted method and subsequent annealing in N2/H2 atmosphere. A detailed array of characterization tools are used to study their morphology, structure and electrochemical performance. It was found that these composites exhibit significantly improved sodium-ion storage ability as compared with pure NS under galvanostatic cycling at a specific current of 100 mA g−1 in a potential limitation of 0.005–3.0 V. Furthermore, the composite with the RGO content of 35 wt.% achieves a high maximum reversible specific capacity of about 391.6 mAh g−1 at a specific current of 100 mA g−1 after 50 cycles. These results prove that NS-RGO composites are highly promising when applied directly as anode materials in sodium-ion batteries.
A three-dimensional (3D) anode comprising a Ni-coated Si microchannel plate (Si-MCP) as the matrix and active materials is prepared by photo-assisted electrochemical etching and electroless deposition. The morphology of the Ni-coated Si-MCP electrode is characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Using lithium foils as the counter electrodes, representative half-cells are fabricated and tested. Galvanostatic charge–discharge (C–D) measurements are conducted between 0.05 and 1.5V and the Ni/Si-MCP anode exhibits a charge capacity of 3520mAhg−1 with a coulombic efficiency close to 95.8% in the initial cycle and above 97% in the second cycle. When the C–D current is stepped up by 25mAhg−1 every 10 cycles, the capacity always reaches the designed one of 1000mAhg−1 until the current reaches 100mAg−1. Based on electrochemical impedance spectroscopy (EIS) data, the mechanism is studied and described.
A new Fe3C-N-doped reduced graphene oxide (Fe3C-N-rGO) prepared by a facile method is used as a separator for high performance lithium-sulfur (Li-S) batteries. The Fe3C-N-rGO is coated on the surface of commercial polypropylene separator (Celgard 2400) close to the sulfur cathode. The special nanotubes are in-situ catalyzed by Fe3C nanoparticles. They could entrap lithium polysulfides (LiPSs) to restrain the shuttle effect and reduce the loss of active material. The battery with the modified separator and sulfur cathode shows an excellent cycle performance. It has a high rate performance, 580.5 mAh/g at the high current rate of 4 C relative to 1075 mAh/g at 0.1 C. It also has an initial discharge capacity of 774.8 mAh/g measured at 0.5 C and remains 721.8 mAh/g after 100 cycles with a high capacity retention of 93.2%. The outstanding performances are notable in recently reports with modified separator.
Battery Equalization systems are necessary as cell imbalance can lead to poor performance and safety hazards. In this paper we present a novel active battery equalization control, based on the Shunt Transistor method, which is feasible for EV battery equalization. Unlike the actual Shunt Transistor control methods that can only operate at the end of the charging process, the proposed smart control is able to accomplish the equalization during both driving and charging EV operations (optimizing time and performance) with a high final efficiency. Balancing is not enough when battery aging manifests; therefore, health management is essential. By taking advantage of the proposed system, a novel on-line unhealthy cell detection and cell change decision function is implemented. The proposed health analysis can be performed during normal driving, without the need for numerous charging/discharging cycles, a considerable data set, or complex models or estimations. Simulation results and experimental validation, in a battery pack made up with three cells, first prove the correct equalization during driving (with a real driving profile) and charging/discharging operations, with high efficiency (over 95%); and secondly, validates the cell health analysis, obtaining a cell health map and detecting the unhealthy cell placed on purpose.
Lithium vanadium fluorophosphate (LiVPO4F/C) nanosheets with uniform carbon coating are successfully synthesized using a hydrothermal method followed by calcination. X-ray diffraction results reveal that the obtained products crystallized in the triclinic LiVPO4F phase. Scanning electron microscope and transmission electron microscope images demonstrate that both vanadium phosphate (VPO4/C) and LiVPO4F/C composites have a very flat sheet-like morphology, with each nanosheet exhibiting a smooth surface and a typical thickness of 50–100 nm. The nanosheets are coated by a uniform layer of amorphous carbon. Electrochemical tests show that LiVPO4F nanosheets deliver a discharge capacity of 143 mAh g−1 at 0.1 C in the range of 3.0–4.5 V at the first cycle and possess a favorable capacity at rates of 0.5, 1, 2, 3 and 5 C.
SnS2 powder made by sonochemistry was applied and examined for anode material of Li ion battery. The annealed SnS2 at 400°C showed a higher capacity of 600mAhg−1 than the non-annealed SnS2. The cell with annealed SnS2 anode and LiCoO2 cathode worked well. From the results, SnS2 material was revealed to be one of the candidates of the anode materials for future Li ion batteries.
Microgrids contain various power systems with different power capacities and generation fluctuations. An overall power management strategy is necessary to manage power flows among all interconnected elements. This paper presents a multi –agent system solution to energy management in a microgrid based on distributed hybrid renewable energy generation and distributed consumption (vital loads and non-sensitive loads). The real model of each element connected is needed, enabling microgrid modeling and control. A new architecture using multi –agent system solution is proposed, allowing making all the calculations required in Matlab Simulink and the intelligent strategy of energy management is executed by agents designed by Jade. While the communication middleware between Jade and Simulink is carried out by MacsimJX. Finally, it was justified how multi agent system can be a suitable solution to microgrid implementation requirements.
Electric mobility is a trending topic around the world, and many countries are supporting electric vehicle technologies to reduce environmental impacts from transportation such as greenhouse gas emissions and air pollution in cities. While such environmental impacts are widely studied in the literature, there is not much emphasis on a comprehensive sustainability assessment of these vehicle technologies, encompassing the three pillars of sustainability as the environment, society, and economy. In this study, we presented a novel comprehensive life cycle sustainability assessment for four different support utility electric vehicle technologies, including hybrid, plug-in hybrid, and full battery electric vehicles. A hybrid multi-regional input-output based life cycle sustainability assessment model is developed to quantify fourteen sustainability indicators representing the three pillars of sustainability. As a case study, we studied the impacts for Qatar, a country where 100% of electricity generation is from natural gas and have a very unique supply-chain, mainly due to a wide range of exported products and services. The analysis results showed that all-electric vehicle types have significant potential to lower global warming potential, air pollution, and photochemical oxidant formation. A great majority (above 90%) of the emissions occurs within the region boundaries of Qatar. In the social indicators, internal combustion vehicles performed better than all other electric vehicles in terms of employment generation, compensation of employees, and taxes. The results highlighted that adoption of electric vehicle alternatives doesn't favor macro-economic indicators and they have slightly less for a life-cycle cost. The proposed assessment methodology can be useful for a comprehensive regionalized life cycle sustainability assessment of alternative vehicle technologies and developing regionalized sustainable transportation policies worldwide.
The current article displays the possibilities of borohydride reduction method, carried out at room temperature and ambient atmospheric condition, to be a technological process for large scale production of Cu6Sn5 nanoparticles. This composition is very attractive recently via anode material in secondary lithium batteries. The content changes of prepared nanoparticles depend on the initial ratio of metal salt solutions and the concentration of complex forming agent used. One hypothesis is draw out on the basis of experimentally analyzed content of electrodes, interrupted at various potentials of the first charge cycle: 690mV, 540mV, 200mV and 10mV. Thus, the good life cycle of these nanoscale systems is a result of an intercalation of lithium occurring during phase transition from hcp to fcc of the lattice.
Previous studies from this lab have demonstrated that in vitro ascorbate augments neutrophil nitric oxide (NO) generation and oxidative burst. The present study was therefore undertaken in guinea pigs to further assess the implication of ascorbate deficiency in vivo on neutrophil ascorbate and tetrahydrobiopterin content, NOS expression/activity, phagocytosis, and respiratory burst. Ascorbate deficiency significantly reduced ascorbate and tetrahydrobiopterin amounts, NOS expression/activity, and NO as well as free radical generation in neutrophils from scorbutics. Ascorbate and tetrahydrobiopterin supplementation in vitro, though, significantly enhanced NOS catalysis in neutrophil lysates and NO generation in live cells, but could not restore them to control levels. Although phagocytic activity remained unaffected, scorbutic neutrophils were compromised in free radical generation. Ascorbate-induced free radical generation was NO dependent and prevented by NOS and NADPH oxidase inhibitors. Augmentation of oxidative burst with dehydroascorbate (DHA) was counteracted in the presence of glucose (DHA uptake inhibitor) and iodoacetamide (glutaredoxin inhibitor), suggesting the importance of ascorbate recycling in neutrophils. Ascorbate uptake was, however, unaffected among scorbutic neutrophils. These observations thus convincingly demonstrate a novel role for ascorbate in augmenting both NOS expression and activity in vivo, thereby reinforcing oxidative microbicidal actions of neutrophils.
Separators with low ionic impedances and high thermal/electrochemical stability are desirable for high-performance Li-ion batteries. Herein, a composite layer consisting of AlPO4, poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) and polymethyl methacrylate (PMMA) is coated on the polypropylene (PP) separator matrix. The coated PP exhibits an electrolyte uptake of 2.28%, leading to improved ionic conductivity and Li-ion diffusion coefficient. In addition, this separator has a wide electrochemical stability window, high peeling strength of 111.2 N m−1 and superior thermal stability at 170 °C. By applying this coated separator in the cell with LiNi0.5Co0.2Mn0.3O2 cathode, excellent cycling stability and rate performance can be also obtained. The improved electrochemical performances can be attributed to that AlPO4 in the coating layer exhibits high electrolyte uptake and firmly combines with the PP matrix.
A MnO2-CeO2/CNT nanostructure is synthesized using hydrothermal method for which the amounts of CNT, CeO2 and MnO2 are determined using TGA and ICP-OES analysis equal to 55%, 25% and 20%, respectively. The MnO2-CeO2/CNT nanocomposite is characterized using SEM, EDS-SEM, XRD, BET, TGA and ICP techniques and used as an efficient cathodic electrocatalyst in the lithium-oxygen battery. The energy storage capacity of the lithium-oxygen battery fabricated using pristine CNT is about 4100mA.h/gelectrode at 100mA/gelectrode current density but that of MnO2-CeO2/CNT nanocatalyst is 7980mA.h/gelectrode at the 50mA/gelectrode current density and 6860mA.h/gelectrode at the 100mA/gelectrode current density showing a 68% improvement in the battery performance. The charge and discharge over-voltages are 0.68 and 0.20V, respectively, for MnO2-CeO2/CNT while they are 1.44 and 0.32V for CNT, respectively, at the 100mA/gelectrode current density exhibiting 52% and 37.5% decrease in charge and discharge over-voltages. The cyclic performance of the MnO2-CeO2/CNT nanostructure cathode is considered at 70 cycles reflecting its appropriate performance. The electrochemical impedance spectroscopy (EIS) illustrates a suitable reversibility for the synthesized cathode in such a way that the resistance created at discharge is diminished at the charging process.
Olivine structured LiFePO4 (lithium iron phosphate) and Ti4+-doped LiFe1−x Ti x PO4 (0.01≤ x ≤0.09) powders were synthesized via a solution route followed by heat-treatment at 700°C for 8h under N2 flowing atmosphere. The compositions, crystalline structure, morphology, carbon content, and specific surface area of the prepared powders were investigated with ICP-OES, XRD, TEM, SEM, EA, and BET. Capacity retention study was used to investigate the effects of Ti4+ partial substitution on the intercalation/de-intercalation of Li+ ions in the olivine structured cathode materials. Among the prepared powders, LiFe0.97Ti0.03PO4 manifests the most promising cycling performance as it was cycled with C/10, C/5, C/2, 1C, 2C, and 3C rate. It showed initial discharge capacity of 135mAhg−1 at 30°C with C/10 rate. From the results of GSAS refinement for the prepared samples, the doped-Ti4+ ions did not occupy the Fe2+ sites as expected. However, the occupancy of the doped Ti4+ ions are still not clear, and theoretical calculations are needed for further studies. From the variation of lattice parameters calculated by the least square method without refinement, it suggested that Ti4+-doped LiFePO4 samples formed solid solutions at low doping levels while TiO2 was also observed with TEM in samples prepared with doping level higher than 5mol%.
In this paper, modeling, analysis, design, simulation and control of a single ended primary inductor converter (SEPIC) are discussed for renewable energy applications. Because the traditional control methods such as proportional–integral–derivative (PID) and classical half-cycle Posicast controllers based on feedforward are sensitive to noise and variations in natural frequency, a Posicast control with feedback structure is proposed and designed to reduce or rejection undesirable sensitivity greatly, to suppress measurement noise and to eliminate the overshoot in the output response. The SEPIC converter is modeled using average value modeling analysis. Dynamic modeling and simulation are accomplished using MATLAB Simulink™ 7.2.
Concept and category learning is critical for intelligent thought and action. However, much of the laboratory work has focused only on classification learning, how people learn to assign category membership. This chapter attempts to integrate concept and category learning to the many cases in which it is critical in three ways. First, we examine other ways of learning, in which the categories are used to accomplish a goal. Second, we investigate more complex concepts and the use of prior knowledge. Third, we briefly consider the role of concept and category learning in problem solving and language use.
The polyanionic cathodes with high safety and appropriate redox potential, attract tremendous attention for Li-ion batteries. However, their high-rate cycling stability and poor industrial feasibility still remain great challenges. Herein, Li3V2(PO4)3 nanoplates with dominate {100} exposed facets embedded in a N-doped carbon matrix are successfully constructed. The in-situ dispersion-chelating approach benefits from reductive hydrogen peroxide and polyacrylamide, which acts as a strong ligand that coordinates the precursors to the polymer chains, resulting in a desirable construction of a highly porous structure (surface area: 69.667 m2 g−1) with homogeneous carbon coating, and thus facilitating structural stability. Therefore, the designed Li3V2(PO4)3/C composite displays competitive capacities with outstanding cycle stabilities (95.8% retention after 500 cycles at 1C rate and 89.1% after 2000 cycles at 20C rate) under both two and three electron exchange conditions. Moreover, theoretical studies are applied to explore the origin of enhanced kinetics. The molecular dynamics simulations demonstrate an anisotropic Li+ diffusion with a fast [100]-oriented diffusion channel. The first-principles calculations reveal that the architecture induced by defect carbon can provide better interfacial stability and electronic conductive medium. This developed strategy combined with mechanism study provides an exciting perspective and avenue for establishing more-efficient electrode materials.