batterydata/paper-abstracts huggingface dataset:
Herein, a layer in layer nanocomposition of flower-shaped MoS2 nanoclusters with nitrogen-doped reduced graphene oxide(N-RGO@MoS2) has been successfully prepared by a facile hydrothermal method to build up 3D matrix for supporting sulfur. This approach will integrate the advantages and avoid the disadvantages of graphene and MoS2 through synergetic effect to produce an outstanding Li-S battery cathode, such as high electronic conductivity of N-RGO to reach great rate performance; stronger interaction between MoS2 and polysulfide to suppress the shuttle effect for an improved durability; the great compatibility between two 2D components avoids their self-aggregation to increase capacity through wrap around and adhesion effect with loaded sulfur. A series of samples with various content of MoS2 are investigated to optimize the electrode performance. Finally, N-RGO@MoS2-10/S delivers an optimal discharge capacity of 729.1mAhg−1 at 0.3C with the coulombic efficiency of 97.3% after 180 cycles.
The structure changes of iron disulfide (FeS2) during discharge/charge process were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and synchrotron-based X-ray adsorption near the edge structure (XANES). Although the cyclability of the FeS2/Na battery is poor, FeS2/Na battery has a large first discharge capacity of 758 mA h g−1. It corresponds to 85% of the theoretical capacity based on the 4.0 Na reaction per FeS2 (893 mA h g−1). According to the Fe K-edge XANES spectra of discharged FeS2 pellets, there were no clear traces of iron valence change. However, the clear S K-edge jump shifted to lower energy with increasing Na content in FeS2. This is because the binding energy of S 1s electrons decrease as the oxidation number of S decreases, suggesting that the charge neutrality of the cathode after 2.0 Na discharge is kept by an S valence change from (S–S)2− to S2−. Moreover, Na2S diffraction peaks were detected at the 3.0 Na discharged state as a trace of Na conversion reaction in the FeS2 cathode.
The aim of this study was to validate a questionnaire on academic competence behaviour for use with Chinese preschool children in Hong Kong. A parent version and a teacher version were developed and evaluated. The participants included 457 children (230 boys and 227 girls) aged four and five years old, their preschool teachers and their parents. Besides, 44 children (39 boys and 5 girls) with developmental disabilities were recruited. The children were assessed on the cognitive domain of the Preschool Development Assessment Scale (PDAS). Their parents completed a questionnaire on academic competence behaviour, as well as the Strength and Difficulty Scale (SDQ). Their teachers completed the questionnaire on academic competence behaviour. Rasch analysis results provided support for the unidimensionality of the parent and teacher versions of the scale, with one item deleted. The parent and teacher versions of the revised scale correlated positively with the cognitive domain of the PDAS and the prosocial scale of the SDQ and negatively with SDQ total problem behaviour score. Children with developmental delay were assigned lower scores by their parents and teachers, compared with preschool children, on the revised versions of the academic competence behaviour scale. Reliability estimates (Cronbach's alpha) of the parent and teacher versions of this revised scale were above .80. The results suggested that the two versions of academic competence behaviour scales were promising instruments for the assessment of academic competence behaviour among Chinese preschool children.
Data is increasingly distributed across heterogeneous networks of mobile nodes such as distributed smartphone applications, where nodes’ access to resources such as battery power, connectivity, or computing power varies, but must still be reliably collected, stored, and retrieved. In this paper, we present a scalable, location aware, hierarchical DHT that utilizes nodes’ varying resource availability levels to increase the mobile network’s data storage and retrieval capabilities. We compare this hierarchical DHT to other location aware flat and hierarchical approaches, examining the structures’ suitability for nodes with varying resource availability, and examine the effects of varying numbers of hierarchy levels.
Publisher Summary Rabies is a unique neurological infection that can be prevented by post-exposure vaccination, at least when the vaccine is administered to patients within a reasonable period of time after a rabies exposure. Thus, vaccine efficiency can be conferred by immunization even after the virus enters the body and reaches the nervous system. Because of the ability of rabies virus to impair immune responsiveness, it is intriguing to understand how immunization against rabies can prevent or limit virus progression toward and/or through the nervous system. In this chapter, the mechanisms involved in specific immune responses as well as the molecular basis of rabies vaccine protection are discussed. Today, with an increased understanding of the particular properties of rabies virus infection, one can propose a biological relevance and rationale for heuristic choices elaborated by former vaccine designers. On the other hand, the success of vaccination of patients after exposures urges to investigate further the mechanisms that sustain the immune B cell response despite the impermeability of the blood-brain barrier to most antibodies.
In flywheel based energy storage systems (FESSs), a flywheel stores mechanical energy that interchanges in form of electrical energy by means of an electrical machine with a bidirectional power converter. FESSs are suitable whenever numerous charge and discharge cycles (hundred of thousands) are needed with medium to high power (kW to MW) during short-time periods (seconds–minutes). Monitoring of the FESS state of charge is simple and reliable as only the spinning speed is needed. The materials for the flywheel, the type of electrical machine, the type of bearings and the confinement atmosphere which all together determine the FESSs energy efficiency (>85%) are reviewed. Main FESS applications: power quality, traction and aerospace are presented. Additionally in this paper it is presented the simulation of an isolated wind power system (IWPS) consisting of a wind turbine generator (WTG), a consumer load, a synchronous machine (SM) and a FESS. A low-speed iron flywheel driven by an asynchronous machine (ASM) is sized for the presented IWPS. The simulation results with graphs for system frequency, system voltage, active powers of the different elements, and FESS-ASM speed, direct and quadrature currents are presented showing that the FESS effectively smoothes the wind power and consumer load variations.
Composite electrolytes composed of a blend of polyethylene glycol diacrylate (PEGDA), poly(vinylidene fluoride) (PVDF) and poly(methyl methacrylate) (PMMA) together with a non-woven fabric have been prepared by means of ultra-violet cross-linking. As the non-woven fabric serves as a mechanical support medium, the composite electrolyte has good integrity up to an initial liquid electrolyte uptake of 1000% (ethylene carbonate (EC)–dimethyl carbonate (DMC)–ethylmethyl carbonate (EMC)–LiPF6). The ionic conductivity of the composite electrolytes reaches 4.5mScm−1 at an ambient temperature of around 18°C and are electrochemically stable up to about 4.8V versus Li/Li+. The conductivity and interfacial resistance remain almost constant even at 80°C. Scanning electron micrographs show that the high-temperature behavior is associated with structural stability that is induced by chain entanglement between PVdF, PMMA and PEGDA network. A MCMB|LiCoO2 cell using the composite electrolytes retains >97% of its initial discharge capacity after 100 cycles at the C/2 rate (150mA), and delivers more than 80% of full capacity with an average load voltage of 3.6V at the 2C rate. The cell also shows much better cycle-life than one with a PVdF-coated composite electrolyte at high temperatures because of the better liquid electrolyte retention capability.
This paper examines alternative strategies for eliminating the use of oil for passenger transportation in light duty vehicles (LDVs: cars, SUVs and light trucks) by 2060, namely, deep reductions in the energy intensity (MJ/vkm) of LDVs combined with a shift to hybrid and/or all-electric vehicles, or combined with a shift of the residual fuel requirements to C-free fuels (either renewable biofuels or hydrogen produced from C-free energy sources, and used in a fuel cell). Different combinations of these measures have dramatically different implications concerning land area requirements (for biofuels), additional electricity requirements (for electric vehicles or to produce hydrogen electrolytically), and in the demand for potentially limiting metals (Pt, Ru, Li and Nd in particular). Recent estimates of battery, fuel cell and motor sizes in advanced vehicles, and corresponding material loadings, are combined with scenarios for the growth of the global vehicle fleet and recycling potential to estimate future material requirements. For any of the alternative to fossil fuels to be sustainable over the next century, it is essential that LDV energy intensity be pushed to the lowest technically achievable potential, that significant reductions in precious metal loadings be achieved, and that 90% or better recycling efficiency be achieved. Even then, longer term sustainability is not guaranteed, which implies that the primary emphasis in urban development and redevelopment over the next century should be to create cities with little to no dependence on the private automobile for transportation.
Background Negative symptoms in schizophrenia are related to impaired functioning. The presence of negative symptoms in early phases of psychosis in individuals at clinical risk is receiving increased attention. Methods We evaluated comprehensively a sample of 92 young people (age range 15–25) applying the Clinical Assessment Interview for Negative Symptoms (CAINS), adapted for youth. Individuals at clinical high risk (CHR, n=29) were compared to individuals with schizophrenia (SZ, n=31) and normal controls (NC, n=32). In addition to the CAINS, participants were assessed with the Structured Interview for Prodromal Syndromes (SIPS), enabling examination of the relations among scales, as well as the Penn Computerized Neurocognitive Battery (CNB), to examine association with cognitive performance, and the Global Assessment of Function (GAF) to assess overall functioning. Results The CHR group was intermediate to SZ and NC on nearly all clinical measures. Negative symptoms on the CAINS correlated better with negative than with other symptoms on the SIPS and were associated with neurocognitive deficits and poorer functioning. Conclusions This study illustrates the feasibility of in-depth evaluation of negative symptoms in youth and indicates that these symptoms are present already in the at-risk state and relate to impaired cognition and functioning.
Aluminum-graphene battery is promising for its abundant raw materials, high power density, ultralong cycle life and superior safety. However, the development of aluminum-graphene battery is currently restricted by its insufficient cathode capacity, calling for a newly developed working mechanism. In addition, an irregular constant increase of the cathode capacity was always observed during cycling, but cannot be explained based on the current understanding. Here, we observed an increase of specific capacity by 60% with stable Coulombic efficiency of 98% during 7000 cycles life of Al-graphene batteries employing AlCl3/ET3NHCl electrolyte. We demonstrated this growing cathode capacity is attributed to an increasing contribution of capacitive charge storage during cycling, because a gradually enlarged surface area as capacitive active sites is enabled by the exfoliation of graphitic cathode during the periodic intercalation process. Moreover, the graphene cathode was exfoliated more significantly in AlCl3/ET3NHCl than 1-ethyl-3-methylimidazolium chloride-based electrolyte, which results from the heavier stress on the graphene layers caused by the larger intercalants in AlCl3/ET3NHCl. The common intercalation of cations with AlCl4 − clusters was therefore supposed to occur during charging. This new proposed mechanism can offer the new thought for future design on high-capacity cathode of Al-ion battery.
The advent of flexible, wearable electronics has placed new demands on energy storage systems. The demands for high energy density achieved through the use of highly conducting materials with high surface area that enable facile electrochemical processes must now be coupled with the need for robustness and flexibility in each of the components: electrodes and electrolytes. This perspective provides an overview of materials and fabrication protocols used to produce flexible electrodes and electrolytes. We also discuss the key challenges in the development of high performance flexible energy storage devices. Only selected references are used to illustrate the myriad of developments in the field.
The LUCAS™ device delivers mechanical chest compressions that have been shown in experimental studies to improve perfusion pressures to the brain and heart as well as augmenting cerebral blood flow and end tidal CO2, compared with results from standard manual cardiopulmonary resuscitation (CPR). Two randomised pilot studies in out-of-hospital cardiac arrest patients have not shown improved outcome when compared with manual CPR. There remains evidence from small case series that the device can be potentially beneficial compared with manual chest compressions in specific situations. This multicentre study is designed to evaluate the efficacy and safety of mechanical chest compressions with the LUCAS™ device whilst allowing defibrillation during on-going CPR, and comparing the results with those of conventional resuscitation.
A cathode material, LiV3O8, for rechargeable lithium-based batteries has been prepared via a combined freeze-drying method and appropriately post-treated in argon atmosphere. It was found that the sample post-treated at 300°C in Ar has the optimal performance. Electrochemical tests performed on this material demonstrated its very high insertion capacity of 347mAhg−1 (3.7 Li+ per LiV3O8) at a current density of 50mAg−1 (C/6). Most important is that it displayed an excellent cycling stability and after 60 cycles, a discharge capacity with 351mAhg−1 was obtained. It was proposed that a short-range crystallographic order had a stronger influence on the electrochemical performance of an electrode material in this work, instead of the surface area, particle size and crystalline degree, etc.
Layered LiNi0.6Co0.2Mn0.2O2 (NMC) is a promising cathode material for lithium-ion batteries, but structural instability and rapid capacity decay at high voltages and elevated temperatures preclude its large-scale commercialization. Lattice doping and surface coating can address these problems, but the different mechanisms between them are still unclear. Herein, two kinds of cathode materials (Zr-doped NMC and ZrO2-coated NMC) are synthesized and the effects of doping and coating on the structural stability and electrochemical performance of NMC are systematically investigated. Zr-doped NMC exhibits superior electrochemical performance with 98% capacity retention after 50 cycles between 3.0 and 4.5 V at 55 °C. In contrast, pristine and ZrO2-coated NMC suffer continual capacity decay during cycling. Ex situ analyses reveal that the performance improvement originates from the structure stabilizing effects of Zr doping and the robust interfacial film on the cathode surface during cycling. The results suggest that lattice doping is a key factor in obtaining excellent cycling performance at high temperatures. This study provides further insight into the different effects of Zr doping/coating and can be extended to investigate other cathode materials.
The vanadium flow battery is a promising electrochemical technology for large-scale energy storage; however, its operational temperature is limited by the low solubility and stability of vanadium ions in sulfuric acid solution. To broaden the operational temperature of the vanadium flow battery while maintaining the non-cross-contamination property of the electrolytes, the complexing agent 1-hydroxyethane-1,1-diphosphonic acid is added to the electrolytes. This compound interacts with the vanadium ions to help stabilize the electrolyte solutions. The results of this study show that the stable temperature range of the electrolyte with 2.0 M vanadium and 2.0 M H2SO4 is increased from 0–25 °C to 0–40 °C by adding 1 wt% 1-hydroxyethane-1, 1-diphosphonic acid. Both the Job plot and the Benesi-Hildebrand plot methods confirm that 1-hydroxyethane-1, 1-diphosphonic acid interacts with VO2+
Developments in digital and communication technology are now reaching the realms that border on science fiction. Computing devices are no longer items that we use in our homes and places of work and carry in our bags and pockets. We can now wear those devices. This article focuses on this development. In doing so, it explores old and recent developments in wearable technology with a focus on their current and potential use in the field of healthcare and medical education. It also highlights the challenges that are likely to face this technology. Moreover, it attempts to provide some insights into the prospects of this technology from the theoretical perspective of the theory of disruptive innovations as proposed by Clayton Christensen and his colleagues from Harvard Business School.
A 3V lithium-ion cell with Li[Ni1/2Mn3/2]O4 (Fd 3 ̄ m; a=8.17Å) and the zero-strain insertion material of Li[Li1/3Ti5/3]O4 (Fd 3 ̄ m; a=8.36Å) was examined with an emphasis on rate-capability and cycle life. This cell showed a quite flat operating voltage of 3.2V with excellent cycleability. Accelerated cycle tests indicated that 83% of the initial capacity was delivered and stored even after 1100 cycles. Although the calculated energy density of a Li[Li1/3Ti5/3]O4/Li[Ni1/2Mn3/2]O4 cell was about 250Whkg−1 or 1000Whdm−3 based on the active material weight or volume, the 3V lithium-ion battery exhibited positive characteristic features, such as flatness in operating voltage, high rate capability, and cycle life.
All-solid-state Li–S batteries have attracted significant attention due to their high energy density and high safety. However, the insulating nature of S has limited the electrochemical performance of all-solid-state systems. Alternatively, Se, possessing orders of magnitude higher electronic conductivities, may be a promising cathode candidate but has been completely overlooked in all-solid-state battery systems. Herein, a feasible all-solid-state Li–Se battery is demonstrated using Se–Li3PS4–C as the cathode, Li3PS4 as the electrolyte, and an Li–Sn alloy as the anode. In addition to the high electronic conductivity (1 × 10−3 S cm−1) of Se, a high Li+ conductivity of 1.4 × 10−5 S cm−1 across the Se–Li3PS4 interface can be achieved. The all-solid-state Li–Se cell shows a high reversible capacity of 652 mA h g−1 (96% of theoretical capacity) and exhibits favorable capacity retention upon cycling. This work demonstrates the advantages of a Se cathode in all-solid-state batteries and provides new opportunities for improving the charge transfer of S cathodes in solid-state batteries.
The muscular dystrophies are a heterogeneous group of disorders for which there are currently no cures. Oculopharyngeal muscular dystrophy (OPMD) is an autosomal dominant late-onset, progressive disease that generally presents in the fifth or sixth decade with dysphagia, ptosis and proximal limb weakness. OPMD is caused by the abnormal expansion of a (GCG)n trinucleotide repeat in the coding region of the poly-(A) binding protein nuclear 1 (PABPN1) gene1. In unaffected individuals, (GCG)6 codes for the first six alanines in a homopolymeric stretch of ten alanines. In most individuals with OPMD this (GCG)6 repeat is expanded to (GCG)8–13, leading to a stretch of 12–17 alanines in mutant PABPN1. PABPN1 with an expanded polyalanine tract forms aggregates consisting of tubular filaments within the nuclei of skeletal muscle fibers2,3,4. We have developed a transgenic mouse model of OPMD that manifests progressive muscle weakness accompanied by intranuclear aggregates and TUNEL-stained nuclei in skeletal muscle fibers. The onset and severity of these abnormalities were substantially delayed and attenuated by doxycycline treatment, which may exert its therapeutic effect by reducing aggregates and by distinct antiapoptotic properties. Doxycycline may represent a safe and feasible therapeutic for this disease.
The deterioration mechanisms of a Ni–metal hydride (Ni–MH) battery system during operation is investigated. A decrease of the discharge voltage is observed at the early stage of the cycle, which indicates the possible occurrence of an unexpected system shutdown of the battery at low state of charge. Cyclic voltammetry and surface examination are used to investigate the causes of this phenomenon. The elution of elements such as Al and Mn from the metal hydride negative electrodes is shown to affect the oxidation/reduction behavior of Co, the conductive material of the positive electrode. Furthermore, the possible methods to strengthen the conductive network of Co, including pretreatment of the positive electrode, addition of conductive material, and precipitation of the elution elements as insoluble compounds to reduce their effect are also investigated. By combining these strategies, deterioration of the conductive network can be prevented in the early stage.
The development of efficient noble-metal free electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is of great importance for energy storage devices, such as fuel cell and zinc-air battery. In this work, we report a facile approach to enhance the electrocatalytic activity of La0.8Sr0.2MnO3-based perovskite by introducing the deficiency in the A-site and transition-metal Fe in the B-site. Bifunctional electrocatalysts La0.8Sr0.2MnO3, (La0.8Sr0.2)0.98MnO3, (La0.8Sr0.2)0.95MnO3 and (La0.8Sr0.2)0.95Mn0.5Fe0.5O3 were prepared by a facile sol–gel process. The material characterization results showed that compared with La0.8Sr0.2MnO3, (La0.8Sr0.2)0.98MnO3 and (La0.8Sr0.2)0.95MnO3 have smaller particle size, more oxygen vacancies and proper Mn valence, which will benefit both ORR and OER. The results were verified by testing the electrocatalytic activities using rotating-disk electrode (RDE) in alkaline media. For the perovskite oxides with only A-site cation deficiency, the bifunctional electrocatalytic activities increase in the following order: La0.8Sr0.2MnO3 < (La0.8Sr0.2)0.98MnO3 < (La0.8Sr0.2)0.95MnO3. With partial substitution of Mn by Fe in the B-site, the (La0.8Sr0.2)0.95Mn0.5Fe0.5O3 perovskite oxide exhibits even better electrocatalytic activity. Further experiments reveal that (La0.8Sr0.2)0.95Mn0.5Fe0.5O3 has the highest current density (4.5 mA cm−2) in ORR which is comparable to commercial Pt/C (5 mA cm−2) and the enhancement of the OER is more obvious than that of the ORR. Subsequently, the perovskite samples were used as the cathode catalysts in zinc-air batteries. The results further prove that proper use of A-site deficiency and B-site Fe doping in perovskite oxides can boost up the electrocatalytic activities.