batterydata/paper-abstracts huggingface dataset:
The voltammetry of micro- and nano-particle modified electrodes and other electrodes of partially covered and non-planar geometry is investigated by simulation. Building on existing theory, it is demonstrated that for a simple one-electron process (assuming that the diffusion fields of neighbouring electroactive regions strongly overlap such that diffusion to the entire surface is linear), the apparent electrochemical rate constant of the reaction, k app , is equal to the product of the true rate constant, k 0 , and the ratio, Ψ, of the total electroactive surface area to the geometric surface area of the substrate. It is demonstrated that for a given value of Ψ, the voltammetry is independent of the surface geometry; surfaces covered by, for example, long thin bands of electroactive material, or electroactive hemispherical or spherical particles, show the same voltammetry if they have the same surface area of electroactive material per area of substrate. Distributions of, most importantly, electroactive nanoparticles, with Ψ > 1 , will display an apparent catalytic effect compared to the bulk material which can be solely due to the geometry of the surface and not necessarily related to changes in kinetics at the nanoscale, for example by altered structural or electronic properties. Further, if an electrode surface is modified by a fixed mass of nanocatalyst per unit area, then the response will reflect the size and shape of the modified particles.
Although guidelines for routine follow-up of pacemakers and implantable cardioverter defibrillators (ICDs) are available for adults, minimal data supports their appropriateness in pediatrics and congenital heart disease. This study aimed to define current practices of cardiac rhythm device (CRD) follow-up among pediatric electrophysiologists. Pediatric and Congenital EP Society (PACES) members were surveyed regarding frequency of CRD in-person follow-up as well as transtelephonic monitoring (TTM) and remote monitoring (RM) practices. If home monitoring was used, the effect on in-person follow-up was also evaluated. A total of 106 PACES members responded to the survey. Uncomplicated pacemaker and ICD patients were both followed in-person at a median interval of 6 months (range 1–12 months). TTM was utilized by 67 % of responders (median interval 3 months; range 1–6 months), while RM was used by 87 % for pacemakers (median interval 3 months; range 1–6 months) and 92 % for ICDs (median interval 3 months; range 2 weeks–6 months). When TTM was used, 21 % of responders reduced their frequency of pacemaker clinic visits. In comparison, RM reduced the frequency of clinic visits for pacemakers and ICDs in 32 and 31 % of responders, respectively. Patient age was an independent factor in determining CRD follow-up for 49 % of responders. While CRD follow-up by pediatric electrophysiologists in general follows adult guidelines, individual practices widely vary. In contrast to published recommendations in adults, TTM and RM utilization does not reduce the frequency of in-person visits for the majority of pediatric electrophysiologists.
In recent years, evidence has accumulated to suggest that mutant huntingtin protein (mHTT) can spread into healthy tissue in a prion-like fashion. This theory, however, remains controversial. To fully address this concept and to understand the possible consequences of mHTT spreading to Huntington’s disease pathology, we investigated the effects of exogenous human fibrillar mHTT (Q48) and huntingtin (HTT) (Q25) N-terminal fragments in three cellular models and three distinct animal paradigms. For in vitro experiments, human neuronal cells [induced pluripotent stem cell-derived GABA neurons (iGABA) and (SH-SY5Y)] as well as human THP1-derived macrophages, were incubated with recombinant mHTT fibrils. Recombinant mHTT and HTT fibrils were taken up by all cell types, inducing cell morphology changes and death. Variations in HTT aggregation were further observed following incubation with fibrils in both THP1 and SH-SY5Y cells. For in vivo experiments, adult wild-type (WT) mice received a unilateral intracerebral cortical injection and R6/2 and WT pups were administered fibrils via bilateral intraventricular injections. In both protocols, the injection of Q48 fibrils resulted in cognitive deficits and increased anxiety-like behavior. Post-mortem analysis of adult WT mice indicated that most fibrils had been degraded/cleared from the brain by 14 months post-surgery. Despite the absence of fibrils at these later time points, a change in the staining pattern of endogenous HTT was detected. A similar change was revealed in post-mortem analysis of the R6/2 mice. These effects were specific to central administration of fibrils, as mice receiving intravenous injections were not characterized by behavioral changes. In fact, peripheral administration resulted in an immune response mounting against the fibrils. Together, the in vitro and in vivo data indicate that exogenously administered mHTT is capable of both causing and exacerbating disease pathology.
A new amorphous-Si@SiOx/Cr/carbon (a-Si@SiOx/Cr/C) anode composite for lithium-ion batteries is synthesized, using SiO, chromium powder and graphite as starting materials. X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), scanning electron microscope (SEM) and high resolution transmission electron microscope (HRTEM) are employed to characterize the composition, morphology and microstructure of the composite. Coin-type cells are assembled to investigate the electrochemical behaviors of the as-prepared composites by constant current charge–discharge technique, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results show that chromium facilitates the crush of Si@SiOx and graphite during milling, and thus improves their mutual dispersion in the composite. When cycled at 100mAg−1, the a-Si@SiOx/Cr/C exhibits a stable discharge capacity of about 810mAhg−1 (calculated on the mass of a-Si@SiOx/Cr/C) with good capacity retention up to 200 cycles. The improved electrochemical performance is attributed to the reduced particle size of a-Si@SiOx and the synergistic effect of carbon and chromium.
Supramolecular conducting oligomeric 1,5-diaminoanthraquinone (DAAQ)-based all solid-state redox supercapacitors have been fabricated with the solid polymer electrolyte, poly vinyl alcohol (PVA)–H3PO4 blend and polymeric gel electrolyte poly methyl methacrylate (PMMA)–ethylene carbonate (EC)–propylene carbonate (PC)–tetra ethyl ammonium perchlorate (TEAClO4) system. The films of gel electrolyte of the optimized composition PMMA (35wt.%)–EC:PC (1:1 v/v)–1M TEAClO4 and polymer electrolyte PVA–H3PO4 (50:50 w/w) blend exhibited high ionic conductivity (10−4 to 10−3 Scm−1 at room temperature) with good mechanical strength, suitable for application in electrochemical supercapacitors. The capacitors have been characterized using a.c. impedance spectroscopy, linear sweep voltammetry and prolonged cyclic test. The maximum capacitance value of 3.7–5.4mFcm−2 (equivalent to single electrode capacitance 125–184Fg−1 of DAAQ electrode) has been observed for the PMMA–gel electrolyte based capacitor. This corresponds to the energy density 92–135Whkg−1. System based on the proton-conducting PVA–H3PO4 polymer blend, however has relatively lower capacitance of 1.1–4.0mFcm−2 (equivalent to single electrode capacitance of 36–136Fg−1).
Sodium iron pyrophosphates Na2−xFe1+x/2P2O7 (x=0; 0.44) have been prepared by mechanochemically assisted solid-state synthesis. The materials were comprehensively characterized and compared by XRD with Rietveld refinement, FTIR, Mössbauer spectroscopy, 23Na and 31P MAS NMR, SEM, EDX, galvanostatic cycling, and GITT. The structure of the as-prepared pyrophosphates was refined in a triclinic symmetry (the space group P-1) differing by the amount and the occupancy of the Fe and Na sites and structural disordering. Both samples contain a considerable amount of the Fe3+ impurities: ∼23% for Na2FeP2O7 (x=0) and ∼7% for Na1.56Fe1.22P2O7 (x=0.44) and the correspondent amount of the Na2CO3 impurity, thus indicating that Na2FeP2O7 is less stable in air atmosphere than Na1.56Fe1.22P2O7. Both pyrophosphates showed good electrochemical activity in hybrid Na/Li-cells upon cycling within the 2.0–4.3V range. Na1.56Fe1.22P2O7 demonstrated superior discharge capacity due to higher porosity, structural disordering and air stability. The formation of new electrochemically active mixed Na/Li-phases with approximate compositions of NaLiFeP2O7 and Na1.2Li0.36Fe1.22P2O7, respectively, and a pristine triclinic structure was identified by ex situ XRD and EDX as a result of the electrochemical Na+/Li+ ion exchange.
Photocatalytic conversion of methane to ethane suffers from low yields due to poor selectivity and quantum efficiency. Now, ethane is produced by a photochemical looping strategy using a nanocomposite of titanium dioxide, phosphotungstic acid and silver cations, with selectivity of 90% and quantum efficiency of 3.5% at 362 nm.
COMT gene is a logical candidate gene for schizophrenia. Moreover, variations in the COMT Val158Met functional polymorphism have been associated with prefrontal cognitive abnormalities among patients with schizophrenia, healthy relatives and controls. In this study, using an epidemiologically-based sample of 130 patients experiencing a first-episode of a non-affective psychosis, we examined whether COMT Val158Met genotype influenced cognitive performance on the phenotypic expression of psychosis. We found no significant differences in any cognitive measure according to COMT genotype. These findings, together with previously published research, put the relationship between COMT genotype and cognitive performance in doubt.
Gathering ecological data for species of conservation concern inhabiting remote regions can be daunting and, sometimes, logistically infeasible. We built a custom-made GPS tracking device that allows to remotely and accurately collect animal position, environmental, and ecological data, including animal temperature and UVB radiation. We designed the device to track the critically endangered Galápagos pink land iguana, Conolophus marthae. Here we illustrate some technical solutions adopted to respond to challenges associated with such task and present some preliminary results from controlled trial experiments and field implementation.
Electroless deposition of cuprous oxide was carried out on Al foil and heat treated at 370°C. Different combination of Carbon/Cuprous oxide composites were prepared and labelled as Al-2, Al-3 & Al-4. Scanning Electron microscopy (SEM) and energy dispersive X-ray (EDX) study revealed the formation of Cu2O for Al-2. FTIR studies revealed presence of Cu2O for non-heat treated Al-2 and CuO for heat treated Al-2. SEM micrograph showed the porous nature of Al-2, whereas, the least porosity was shown by Al-3. The resultant foils were electrochemically characterized using Cyclic Voltammetry, Electrochemical impedance spectroscopy and Galvanostatic Charge Discharge techniques. On deposition of carbon on cuprous oxide surface, capacitance value of the composite decreased. Among them capacitance of Al-2 was found to be 475mFg−1 from the galvanostatic charge discharge studies. The capacitance was found to be 419.12mFg−1 and 296.87mFg−1 for Al-3 and Al-4 respectively.
To achieve high energy and power density simultaneously in miniaturized electronic devices, a zinc-ion micro-supercapacitor (ZmSC) is constructed for the first time by integrating a battery-type zinc micro-anode and a capacitor-type carbon nanotube micro-cathode. In the meantime, an electroplating method is developed to in situ replenish the zinc anode when needed without destroying the configuration of the ZmSC, in which the micro-cathode, micro-anode and electrolyte of the ZmSC function as the working electrode, counter electrode and plating solution in the plating process, respectively. This strategy effectively avoids the irreversible consumption of the zinc anode and the fading of the capacitance and cycle life. As a result, the prepared ZmSC exhibits an excellent electrochemical performance, including a high area capacitance of 83.2 mF cm−2 at 1 mA cm−2, a high energy density of 29.6 μW h cm−2 and a high power density of 8 mW cm−2. After 6000 cycles, the ZmSC shows about 87.4% retention (60.9 mF cm−2) of its initial area capacitance at 5 mA cm−2. Furthermore, a higher capacitance (76 mF cm−2) and a longer cycling life are obtained after re-plating the zinc anode. This method features a simple configuration and easy operation, and holds great promise for use in other long cycle life zinc-based microdevices.
Application of integrated PV-battery systems for off-grid locations has a history exceeding four decades. With the observed fast reduction of PV and battery system prices in recent years, however, interest in the use of PV-battery systems has notably increased even at on-grid locations. The aim of this paper is to assess the impact of various technoeconomic parameters, such as geographic location, weather condition, electricity price, feed-in tariff, PV/battery system cost, and PV/battery specifications on the economic feasibility of grid-connected PV-battery systems. For this, we have used our inhouse decision support tool for investment decision making, optimal sizing, and operation scheduling of grid-connected PV/battery system with respect to these parameters. The results show that decision on the selection of the right PV-battery system is significantly sensitive to each and every one of these parameters. Within various price scenarios that we carried out, battery shows positive impact on NPV only at low installation costs (e.g. ≤750 $/kWh). Neither the sales electricity tariff nor the feed-in tariff has alone a direct impact on the feasibility of installing a battery system. Rather, the magnitude of the difference between electricity price and feed-in tariff is the detrimental element in battery attractiveness. A case-study for Sydney, Australia, showed that at current sales/feed-in electricity tariffs, PV systems with prices of 2700 $/kW, or less, not only reach parity with the grid electricity price but also reach parity with feed-in tariff. This implies the viability of installing large PV systems merely for selling the generated electricity to the grid.
Collection costs associated with servicing a major UK charity’s donation banks and collecting unsold goods from their retail shops can account for up to 20% of the overall income gained. Bank and shop collections are commingled and are typically made on fixed days of the week irrespective of the amounts of materials waiting to be collected. Using collection records from a major UK charity, this paper considers what vehicle routing and scheduling benefits could accrue if bank and shop servicing requirements were monitored, the former using remote sensing technology to allow more proactive collection scheduling. A vehicle routing and scheduling algorithm employing tabu search methods was developed, and suggested time and distance savings of up to 30% over the current fixed schedules when a minimum bank and shop fill level of between 50% and 60% was used as a collection trigger. For the case study investigated, this led to a potential revenue gain of 5% for the charity and estimated CO2 savings of around 0.5tonnes per week across the fleet of six heterogeneous vehicles.
The cognitive underpinnings of arithmetic calculation in children are noted to involve working memory; however, cognitive processes related to arithmetic calculation and working memory suggest that this relationship is more complex than stated previously. The purpose of this investigation was to examine the relative contributions of processing speed, short-term memory, working memory, and reading to arithmetic calculation in children. Results suggested four important findings. First, processing speed emerged as a significant contributor of arithmetic calculation only in relation to age-related differences in the general sample. Second, processing speed and short-term memory did not eliminate the contribution of working memory to arithmetic calculation. Third, individual working memory components—verbal working memory and visual–spatial working memory—each contributed unique variance to arithmetic calculation in the presence of all other variables. Fourth, a full model indicated that chronological age remained a significant contributor to arithmetic calculation in the presence of significant contributions from all other variables. Results are discussed in terms of directions for future research on working memory in arithmetic calculation.
Proton exchange membrane fuel cell (PEMFC) has important implications for the success of clean transportation in the future. One of the key factors affecting the cost and performance of PEMFC is the cathode electrocatalyst for the oxygen reduction reaction (ORR) to overcome sluggish kinetics and instability in an acidic environment. As an essential component of the electrocatalyst, the support material largely determines the activity, mass transfer, charge transfer, and durability of the electrocatalyst. Thereby, the support material plays a critical role in the overall performance of the electrocatalyst. Carbon-based materials are widely used as electrocatalyst supports because of their high porosity, conductivity, chemical stability, and tunable morphology. Recently, some new carbon-based materials with excellent structure have been introduced, such as carbon nanotubes, carbon nanowires, graphene, metal–organic framework (MOF)-derived carbon, and biomass-derived carbon materials. Combined with a variety of strategies, such as controllable construction of porous structures and surface defects, proper doping heteroatoms, the ingenious design of model electrocatalysts, and predictive theoretical calculation, a new reliable path was provided for further improving the performance of electrocatalysts and exploring the catalytic mechanism. Based on the topic of carbon-based materials for ORR in acidic medium, this review summarizes the up-to-date progress and breakthroughs, highlights the factors affecting the catalytic activity and stability of ORR electrocatalysts in acids, and discusses their future application and development.
Previous investigations have shown that high-energy lithium-ion sulfur batteries could be directly assembled with lithium sulfide (Li2S) cathode and a non-lithium anode. However, the existing lithium-ion sulfur battery suffers from the multistep sophisticated preparation process, high activation potential and also polysulfides corrosion to the anode. In this work, we propose and prepare a facile and feasible Li2S-based lithium-ion sulfur battery system, which is enabled by a bifunctional electrolyte additive. At first, Li2S particles were loaded on the low-cost carbonized commercial wipes by a solution-based infiltration method. Interestingly, for the first time, it is found that the well-designed indium triiodide (InI3) electrolyte additive not only performed as a cathodic redox mediator, reducing the activation potential of Li2S cathode, but also resulted in a passivation layer, preventing the anode from corrosion due to the shuttle effect. The obtained SnO2/Li2S full cell exhibits a stable electrochemical performance (983, 878, 746 and 675mAh/g at 0.2, 0.4, 0.8, and 1.5C, 647mAh/g after 200 cycles at 0.5C). Moreover, the manageable amount of lithium ions and the voltage cooperation between the cathode and anode in the full cell rendered the battery with a strong recovery ability against the abusive conditions test, such as over-charge, over-discharge and short-circuit, showing a great potential for practical use.
A series of morphology/component-controllable Sn-Sb micro/nano-structures are fabricated by a one-pot replacement reaction technique employing metallic Sn as both template and reducing agent. Typically, nanoscaled Sn as template and ethyl alcohol as solvent give the hollow structure, while micron-sized Sn as precursor and ethylene glycol as solvent produce the dendritic product. Other mixed structures are also obtained by this one-pot route. As anode materials for lithium-ion batteries, the hollow or dendritic Sn-Sb materials exhibit higher discharge capacities compared with the corresponding Sb samples as well as the Sn templates. Especially, for the Sn-Sb hollow spheres, a high discharge capacity of 820.7 mAh g−1 after first cycle and a reversible capacity of 751 mAh g−1 are achieved after 100 cycles at a current density of 100 mA g−1. Meanwhile, the hollow Sn-Sb structure delivers a specific capacity of 451.3 mA h g−1 at 500 mA g−1 after 150 cycles when used for sodium ion batteries. The superior electrochemical performance that are higher than many reported results can be attributed to the special morphology and structure, which can shorten the transportation distance of lithium/sodium ion and provide extra free space to buffer the volume expansion during the lithium/sodium insertion/extraction.
A property of interface between solid electrode and solid electrolyte is one of the most important keys to fabricate all-solid-state lithium ion battery. In this study, an influence of sol composition used for preparation of the electrode on the property of interface between electrode and electrolyte was examined. LiMn2O4/honeycomb Li0.55La0.35TiO3 (LLT) and Li4Mn5O12/honeycomb LLT half cells were fabricated by impregnation of mixture of active materials with various precursor sols into honeycomb holes. In the case of LiMn2O4 cathode, the sol composed of nitrate salt provides large contact area of LiMn2O4 and LLT, resulting in higher performance of the cell. Li2MnO3 impurity was produced at Li4Mn5O12/LLT interface prepared by the precursor sol composed of only nitrate or acetate salts although no impurity phase was observed at the interface prepared by acetate–nitrate sol containing lithium acetate and manganese nitrate. Li4Mn5O12/honeycomb LLT half cell prepared by the acetate–nitrate sol showed the best performance among them. It is concluded that composition of the precursor sol strongly influenced on the interface of electrode and electrolyte. The all-solid-state Li ion battery composed of LiMn2O4/honeycomb LLT/Li4Mn5O12 was successfully operated and the discharge capacity was 32μAhcm−2.
The progress in the research and development of high temperature sodium batteries suggests that all-solid-state batteries with inorganic or polymer solid electrolytes are promising power sources for a wide range of applications due to their high thermal stability, reliability, long-cycle life and versatile geometries. The electrolytes play a fundamental role in terms of current (power) density, the time stability, and the safety of batteries and, as a result, their continuous improvement and innovation are indeed critical to success. In fact, inorganic solid electrolytes pave the way for improving the cost-effective development of rechargeable sodium batteries. This review describes a state-of-the-art overview of most of the Na+ conductors for use as electrolytes in sodium/sulphur and ZEBRA batteries. The emphasis of this article is on inorganic solid electrolytes, especially, ceramic and glass-ceramic electrolytes as promising alternatives applicable to all solid-state batteries. As part of a continuous effort to find new materials that operate at room temperature and moderate temperatures, NASICON electrolytes will also be considered. Polymer electrolytes based on poly(ethylene oxide) (PEO) are also very suitable for all solid-state batteries. Hence, the review focuses on ion transport based on the observed conductivity, electrolyte preparation, safety and environmental impact.