batterydata/paper-abstracts huggingface dataset:
A two-dimensional thermal model was presented to predict the temperature distribution of cylindrical 8-Ah Ni/MH battery. Under the forced convection, the temperature rise of the battery is up to about 37, 42 and 51°C, and the temperature profiles become non-uniformed at the end of 1C, 2C and 4C rate charge, respectively. It is indicated that the increase of the convection coefficient can decrease the battery temperature, however, lead seriously to the less uniform temperature profile across the battery. The numerical studies indicate that the increase of thermal conductivity can improve the uniformity of temperature profile to some extends. The battery temperature increases obviously when charged at higher rates. Overcharge can result in an increasingly higher temperature rise and a steeper temperature gradient within a battery.
LiFePO4/C particles were coated with highly conductive La0.6Sr0.4CoO3−δ (LSC) via a suspension mixing method followed by heat-treating. The effects of LSC coating were studied by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), galvanostatic charge/discharge test, electrochemical impedance spectroscopy (EIS), potential step chronoamperometry (PSCA) and cyclic voltammetry (CV). The results of HRTEM and XRD showed that the incomplete carbon network could be repaired by nanometer-sized LSC while the co-coated composite retained the structure of LiFePO4. Electrochemical test results indicated that LSC coating could significantly improve the electrochemical performances at high charge/discharge rates. The 4wt.% LSC-coated LiFePO4/C sample exhibited the best electrochemical performance with discharge capacities of 136, 125 and 96mAhg−1 at the rates of 1, 2 and 5C, respectively. These data were much higher than those of the uncoated sample. This improvement could be mainly attributed to the lower charge transfer resistance and higher diffusion coefficients of Li+ ions resulted from the higher conductivity of LSC and the faster kinetic process between the LSC/LiFePO4 interfaces.
A new design and fabrication of anode materials with perfect synthesized performance has been developed. The carbon fibers (CFs) are well suited for multifunctional lightweight design because of the high specific tensile stiffness, ultimate tensile strength (UTS), and high lithium (Li)-intercalation capability. Thus, the CFs can integrate the structural reinforcement part with the battery electrode to store the energy. However, the limitation of low theoretical capacity of commercial CFs for the structural lithium-ion battery (SLIB) is an urgent issue that should be settled. Therefore, this work compounds a novel CFs@Co3O4 composite, which has been successfully fabricated by thermal treatment of CFs@ZIF67 precursor. The performances of the as-prepared products have been enhanced by covering the cobaltic oxide polyhedra firmly on CFs to form a synergetic electrode. The as-obtained CFs@Co3O4 possess well-defined porous structure, which exhibits excellent Li storage properties including high reversible capacity of 420mAhg−1 at 100mAg−1 without obvious decay up to 150cycles (a huge increase as high as 282% than that of the CFs). Furthermore, this work demonstrates a facile and affordable preparation of other CFs@metal oxide composites that hold great promise in the field of energy storage and will become the promising candidate anode materials for SLIBs.
A polymer electrolyte membrane fuel cell (PEMFC) stack has been operated under low humidity conditions during 1000h. The fuel cell characterisation is based both on polarisation curves and electrochemical impedance spectra recorded for various stoichiometry rates, performed regularly throughout the ageing process. Some design of experiment (DoE) techniques, and in particular the response surface methodology (RSM), are employed to analyse the results of the ageing test and to propose some numerical/statistical laws for the modelling of the stack performance degradation. These mathematical relations are used to optimise the fuel cell operating conditions versus ageing time and to get a deeper understanding of the ageing mechanisms. The test results are compared with those obtained from another stack operated in stationary regime at roughly nominal conditions during 1000h (reference test). The final objective is to ensure for the next fuel cell systems proper operating conditions leading to extended lifetimes.
Spinel LiMn2O4 is a very promising material for positive electrodes in a wide range of Li-ion battery applications due to its lower cost and more environmental friendliness than any other electrode materials. Although the bulk properties of LiMn2O4 have been studied intensively, there have been few reports about the structure and properties of LiMn2O4 surfaces in spite of the importance of solid/electrolyte interfaces. This is caused by the difficulty in preparing LiMn2O4 samples with accessible flat surfaces suitable for atomistic observations. To address this, we have successfully prepared a single crystalline LiMn2O4 film with an atomically flat surface by solid-state reaction from a MnO wafer with LiOH.H2O powder. X-ray diffraction (XRD) reveals the single crystalline growth of LiMn2O4 films depending on the orientation of a MnO wafer. Atomic force microscopy observations revealed that a LiMn2O4 (111) film has an atomically flat surface with steps of a {111} interlayer height. Electron energy-loss spectroscopy (EELS) study of the (111) film revealed that the sample consists of Li, Mn3+ and Mn4+ with a composition similar to LiMn2O4. The (111) film sample is also investigated by cyclic voltammetry and galvanostatic experiments, revealing that a crushed powder sample from the film has electrochemical activity as usual positive electrode material.
The utilization of a hybrid battery system (combination of different battery packs via dc/dc converter) in an electric vehicle application is discussed. It is investigated whether battery aging in an electric vehicle can be reduced by using a hybrid battery system. Cycle aging measurements of lithium-ion battery cells were performed at 23 °C against the background of the latter application. Recommendations for hybrid battery system electric vehicle operation are given. For Panasonic NCR 18650 BD cylindrical high energy cells (graphite anode, Li(NiCoAl) O2 cathode), three cycle aging campaigns were conducted systematically, evaluating the impact of charging as well as discharging loads with different time scales and microcycling per driving distance. A significant impact of recuperation pulse duration on aging per driving distance could be observed, whereas varied discharge load characteristics did not vary the aging characteristics. On the basis of differential open circuit voltage analysis, possible degradation mechanisms are discussed. The main driver of capacity loss and resistance increase in cycle aging campaigns with real world driving cycles appears to be the loss of cyclable lithium. Within the operating conditions investigated here, anode aging is intensified with increasing recuperation pulse duration. Another cycle aging campaign with symmetric current rate of 10C for a prismatic high power battery cell (Li4Ti5O12 anode, metal oxide cathode) yielded excellent cycle performance of this cell.
In this study we will analyze the impact of a mindfulness program upon the graphic creativity levels of a group of Latin American teenagers currently living in Spain. To do so, we analyzed an experimental group of Latin American teenagers who took part in the mindfulness training program, and a control group who did not take part in it. The levels of graphic creativity of both groups were evaluated by means of the Torrance Thinking Test of the Graphic Battery. The statistical study showed how the levels of fluency and originality have significantly increased if compared with the levels of the control group. The results of this research prove the usefulness of mindfulness techniques as useful and effective strategies for graphic creativity improvement, and may become an empiric support so as to incorporate and use them within the educational environment.
Objective: Some experimental and observational data suggest a role of estrogen in depression. Raloxifene is a selective estrogen receptor modulator (SERM) approved for the prevention and treatment of postmenopausal osteoporosis. Its influence on mood in postmenopausal women has not been fully established. Thus, we investigated the effect of raloxifene on mood. Methods: In a randomized double-blind osteoporosis prevention study, the action of raloxifene on mood was assessed in a subgroup of non-depressed postmenopausal women (mean age: 58.9 years) receiving raloxifene 60 mg/day (n=18) or placebo (n=18). The Hamilton Depression Rating Scale (HDRS) was applied to evaluate mood 3 and 12 months following treatment. Results: Baseline HDRS scores were not different among treatment groups. Overall scores decreased from baseline at 3 and 12 months in the raloxifene group (P≤0.006), but not in the placebo group. Depression and anxiety indexes decreased in the raloxifene group at 3 and 12 months (P≤0.04); only anxiety index at 12 months decreased in the placebo group (P=0.045). Conclusions: These preliminary results suggest that raloxifene does not negatively influence mood in non-depressed, younger postmenopausal women. Larger, long-term studies are required to evaluate a possible mood improvement effect of raloxifene.
Lithium sulfur (Li-S) batteries are very promising electrochemical storage system due to their high gravimetric energy density and low cost. Enormous efforts have been put on Li-S battery to achieve its commercialization. The function of electrolyte is a key issue in achieving the high performance of Li-S system, and several additives have been tried. But very few works have been working on the electrolyte optimization method with the consideration of over-all performance, including cycling stability, rate capability, especially self-discharge prevention ability, and the consideration of loading condition. In this work, we focus on the incorporation of room temperature ionic liquid (IL) as co-solvent, and the effect of IL in mitigating the polysulfide dissolution via systematical mechanism study of self-discharge phenomena. Moreover, the optimization of IL incorporation ratio is discussed for the sake of the better over-all electrochemical performance of Li-S cell by considering cycling stability, rate performance and self-discharge prevention ability, which is found to vary with loading condition. The improved understanding of the effect of IL on battery performance will help the development of electrolyte for Li-S batteries.
Photovoltaic (PV) insolation-harnessing is acknowledged as the most practical economic solution to meet the requirements of one hundred million people without electricity in the developing countries. Industrialized countries in particular, have been active in utilizing such technologies because they can afford the current peak watt prices of US $3–15 for such systems. The market in those countries will soon be close to saturation and attention by suppliers will have to be shifted to the already established larger market in less developed countries (LDCs). PV marketing in these developing countries, i.e. ability to penetrate the potential market, is facing tremendous hurdles. This paper reviews the present status and future directions of the PV market in developing countries as well as discusses the current technical, social, financial or geopolitical barriers and constraints, which are making this market difficult at present. Possible policy frameworks are also proposed which are in line with the trends in the world. The paper concludes by making a global policy package proposal, in terms of an appeal on the global community concerned with PV to propagate this proposal more convincingly, perhaps to emanate from an internationally recognized “forum”, like a PV conference and exhibition, with cooperation and participation of PV manufacturers, suppliers, industrialized countries, NGOs, financial institutions and developing countries.
The dolphinfish, Coryphaena hippurus, is a fast-swimming, predatory fish exhibiting relatively fast growth and early maturation among marine teleosts. It is an important, potentially renewable resource throughout its global subtropical-to-tropical range. Understanding the ecology of this wide-ranging fish is critical to proper fisheries management, but studies have historically depended heavily upon aggregated catch data reported by fisheries. This study uses tagging data to explore finer scale dolphinfish movements in two subregions of the Eastern Pacific Ocean (EPO)—the west coasts of Baja California Peninsula (WBC) and Oaxaca (OAX), Mexico.
Lithium-sulfur (Li–S) battery system shows immense potential as energy storage devices with high energy density. However, the soluble property of polysulfides into the electrolyte during charge/discharge process leads to low sulfur utilization, severe polarization and short cyclic life, which has been a serious obstacle for practical application. How to anchor the polysulfides onto the cathode materials and moreover, enhance its further conversion to the final products, have been important challenges for the utilization of Li–S batteries. Herein, a novel well crystallized nanosized Fe7S8 possessing of a high specific surface area of 55.6 m2 g−1 fabricated by a simple microwave-assisted method combined with high temperature pyrolysis technique, is introduced into the S/C composite cathode for the first time. Strong interaction between polysulfides and the Fe7S8 can be realized to relieve the shuttle effect. The redox reaction of polysulfides can also be promoted to reduce electrode polarization. As a result of the enhanced utilization of sulfur, the optimized S@GFS-15 electrode may deliver a high initial discharge capacity of 1307.2 mA h g−1 at 0.1 C (1 C = 1675 mA h g−1) and low decay rates of 0.047% and 0.037% per cycle after 1000 cycles at 1 and 2 C respectively when the sulfur loading is ordinary 1.1 mg cm−2. Even the sulfur loading rises up to 2.6 mg cm−2, a large initial discharge specific capacity of 1134.5 mA h g−1 can be achieved at 0.1 C. After 600 cycles, the specific capacity of 457.3 mA h g−1 with a relatively small average decay rate of 0.062% per cycle can be obtained. Thus, incorporation of the nanosized Fe7S8 with graphene can help to achieve effective performance improvement route for Li–S batteries.
Background Cognitive impairments are present during the early course of schizophrenia, and the contribution of GABAergic dysfunction to these cognitive impairments has received increasing attention. Cortical GABAergic inhibition can be assessed using short-interval intracortical inhibition (SICI) in a paired-pulse transcranial magnetic stimulation (ppTMS). The aim of this study was to examine the relationship between cortical GABAergic inhibition and cognitive function in recent onset schizophrenia patients using ppTMS and a neuropsychological battery. Methods The subjects were 20 healthy controls (HC group) and 20 patients with schizophrenia whose duration of illness was less than three years (SZ group). All subjects underwent ppTMS measurements of SICI and intracortical facilitation (ICF), and cognitive performance of the SZ group was assessed using the Brief Assessment of Cognition in Schizophrenia Japanese-language version. We examined group differences in ppTMS measurements (resting motor threshold, SICI, and ICF). In the SZ group, we assessed the relationship between SICI and cognitive performance, and the relationships between SICI and age, duration of illness, medications, and psychopathology. Results The SZ group showed a significant reduction of SICI compared to the HC group, and demonstrated a significant correlation between the reduction of SICI and impaired performance of a working memory task. The HC and the SZ groups did not differ significantly in resting motor threshold and ICF. The SZ group did not show any significant correlations between SICI and age, duration of illness, medications, or psychopathology. Conclusions Our results suggest that the reduction of cortical GABAergic inhibition is related to impairment of working memory in patients with recent onset schizophrenia.
Men and women differ statistically in the relative lengths of their index and ring fingers; and the ratio of these lengths has been used as a biomarker for prenatal testosterone. The ratio has been correlated with a wide range of traits and conditions including prostate cancer, obesity, autism, ADHD, and sexual orientation. In a genome-wide association study of 979 healthy adults, we find that digit ratio is strongly associated with variation upstream of SMOC1 (rs4902759: P = 1.41 × 10−8) and a meta-analysis of this and an independent study shows a probability of P = 1.5 × 10−11. The protein encoded by SMOC1 has recently been shown to play a critical role in limb development; its expression in prostate tissue is dependent on sex hormones, and it has been implicated in the sexually dimorphic development of the gonads. We put forward the hypothesis that SMOC1 provides a link between prenatal hormone exposure and digit ratio.
Lithium-ion cell field failures due to internal short circuits are a significant concern to the entire lithium-ion cell market from consumer electronics to electric vehicles. While the probability of these failure events occurring is estimated to be very low (1 in 5–10 million), the consequences of a cell failure due to an internal short in a high energy battery system have the potential to be catastrophic. The statistical probability of one of these events is very low and they are difficult to predict and simulate in a laboratory using some external test; which makes cell failure due to an internal short circuit a unique challenge to overcome. Several of the experiments designed to simulate internal shorts have been adopted as testing protocols across the industry; in general, they do not accurately simulate an internal short. This work highlights our efforts to experimentally trigger an internal short circuit in a lithium-ion cell.
The design of bifunctional non-precious metal catalyst with good ORR and OER activity is of great significance for the development and commercialization of fuel cells. However, the sluggish and strong irreversible nature of the oxygen electrochemical kinetics makes it difficult to manufacture single bifunctional material. Therefore, we prepared a bifunctional catalyst (Co3O4/N-rGO) with different particle diameters through a one-pot synthesis method, and studied the dependence of the electrocatalytic performance of the catalyst on the particle size of Co3O4. The results showed that Co3O4/N-rGO with 27–31 nm particle size prepared by using N-rGO as the carrier, cobalt acetate concentration of 0.075 M, hydrothermal temperature of 190 °C, and hydrothermal time of 3 h takes a 4e-reaction pathway, which exhibited better ORR and OER activity, excellent current stability and methanol tolerance than JM 20% Pt/C and JM 5% RuO2/C.
Aeromonas hydrophila is a facultative anaerobe which, under conditions of oxygen depletion, uses Fe(III) as electron acceptor. A. hydrophila produces pili during growth with Fe(III). The study was focused on the characterization of the morphology, the electrical properties and the nature of the bacterial pili. Scanning electron microscopy and conductive-probe atomic force microscopy revealed the presence of filaments between cells and substrate and their conductive nature. Our results indicate that pili of A. hydrophila strain A might serve as biological nanowires, transferring electrons from the cell surface to the surface of Fe(III) oxides and, in addition, the possibility of playing a role in inter/intra species signaling. Quorum sensing (QS) is recognized as one of the main regulatory ways for extracellular polymeric substances (EPS) production and biofilm formation. We present evidence that nanowire formation can be regulated by addition of synthetic acyl-homoserine lactones (AHL). These conductive pili may be involved in various interactions, and their protein components might be usable in the future for biotechnological approaches in materials science.
Conduction has been one of the main barriers to further improvements in Li-ion batteries and is expected to remain so for the foreseeable future. In an effort to gain a better understanding of the conduction phenomena in Li-ion batteries and enable breakthrough technologies, a comprehensive survey of conduction phenomena in all components of a Li-ion cell incorporating theoretical, experimental, and simulation studies, is presented here. Included are a survey of the fundamentals of electrical and ionic conduction theories; a survey of the critical results, issues and challenges with respect to ionic and electronic conduction in the cathode, anode and electrolyte; a review of the relationship between electrical and ionic conduction for three cathode materials: LiCoO2, LiMn2O4, LiFePO4; a discussion of phase change in graphitic anodes and how it relates to diffusivity and conductivity; and the key conduction issues with organic liquid, solid-state and ionic liquid electrolytes.
A passive device is utilized for transferring methanol into water through a wick material. The wick material preferentially has a higher wicking capability with respect to methanol than water, and operates in a siphon fashion with the intake end in contact with methanol and the discharge end in contact with water. Due to the difference of wicking capabilities, a net amount of methanol is pumped into water. The device described above is used as a fuel delivery component for a liquid-feed fuel cell system, such as a direct methanol fuel cell (DMFC), which directly utilizes a liquid fuel without an intermediate reforming process. In the present experimental study, methanol and water are stored separately in two containers and a wick is positioned between the containers as a siphon, with the aqueous methanol solution communicating with the anode of the DMFC. Methanol is siphoned from the methanol container to the water container in situ when the methanol in the water is consumed during the operation of the fuel cell. Through a proper selection of the wick and the containers, the methanol concentration near the anode of the DMFC was maintained within a preferred range.
Phase transition and structural degradation of nickel-rich cathode materials are harmful to electrochemical stability, which is unfavorable for the application in high energy density lithium-ion batteries. In this study, the decorated LiNi0.6Co0.2Mn0.2O2 with reconstructed surface on the primary particles is obtained simultaneously during the synthesis process of the material with a facile one-step method. The surface of primary particles decorated with Li3PO4 is well understood to clarify the decoration role in enhancing the charge/discharge performance of the high nickel cathode material. Detailed analysis of LiNi0.6Co0.2Mn0.2O2 cathode surface structure during the charge-discharge process is implemented by high resolution transmission electron microscopy, electron energy-loss spectroscopy, X-ray photoelectron spectrometer et al. It is indicated that the decorated LiNi0.6Co0.2Mn0.2O2 material is stabilized by a spine phase hindering the transformation of layered structure towards rock-salt phase on the surface with cycling. As a result, the decorated LiNi0.6Co0.2Mn0.2O2 material displays outstanding electrochemical performance. It delivers a good capacity retention of 95.3% and 94.3% after 50 cycles at 2C and 5C under high cutoff voltage (2.7–4.5V), respectively, and it is much higher than that of the pristine samples, 87.8% and 86.5%.