batterydata/paper-abstracts huggingface dataset:
Mesoporous bowl-like LiFePO4/C composites were synthesized by a wet milling-spray drying-carbothermal reduction (WSC) using starch as the organic carbon source and reductive agent. The samples were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) analysis, cyclic voltammograms (CV), electrochemical impedance spectra (EIS) and galvanostatic charge–discharge testing. Most of the mesoporous bowl-like LiFePO4/C composites with particle size in the range 5–10μm, coated with evenly distributed carbon, were assembled by nanoparticles (<100nm), and had a mesoporous structure with the pore size of 13.30nm and a speciﬁc surface area of 29.40m2 g−1. These delivered a discharge capability of 123mAhg−1 at 10 C, with no capacity loss after 100 cycles. The enhanced electrochemical performance was mainly ascribed to the improved ionic/electronic conductivity and structural stability arising from the interconnected mesoporous pores, carbon-coated nanoparticles and micro-sized structure.
The aim of the present work is to demonstrate that an efficient all solid electric double layer capacitor (EDLC) may be realised with electrolyte membrane and carbon based electrodes prepared by using a Nafion ionomer solution. Polymer membrane was prepared by a casting method. Electrodes were prepared with two overlapped layers formed of a carbon–Nafion layer and a carbon paper substrate. Three different electrolyte separators in capacitor configuration have been tested and compared: (1) a commercial Nafion 115 membrane (N115), (2) a membrane prepared by casting the Nafion 1100 solution (NRG50) and (3) a porous glass fibre matrix impregnated with a 1 M H2SO4 solution (FVH2SO4). The membrane and electrodes assemblies (MEA) had thickness of 0.6–0.8 mm and geometric area of 4 cm2. The EDLCs characteristics have been studied by conductivity, cyclic voltammetry and DC charge–discharge methods. Proton conductivities of 5.7×10−2 and 3.1×10−2 S cm−1 have been measured at room temperature for the N115 and the NRG50, respectively. Specific capacity of 13.2 F g−1 has been obtained by capacitor utilising the cast Nafion membrane. This value is 70% of specific capacity obtained from the capacitor using sulphuric acid and about 140% of that using Nafion 115.
In the past four years major improvement of the lithium sulfur battery technology has been reported. Novel carbon cathode materials offer high sulfur loading, sulfur utilization and cycle stability. An often neglected aspect is that sulfur loading and amount of electrolyte strongly impact the performance. In this paper, we demonstrate how the amount of electrolyte, sulfur loading, lithium excess and cycling rate influences the cycle stability and sulfur utilization. We chose vertically aligned carbon nanotubes (VA-CNT) as model system with a constant areal loading of carbon. For a high reproducibility, decreased weight of current collector and good mechanical adhesion of the VA-CNTs we present a layer transfer technique that enables a light-weight sulfur cathode. The sulfur loading of the cathode was adjusted from 20 to 80 wt.-%. Keeping the total amount of electrolyte constant and varying the C-rate, we are able to demonstrate that the capacity degradation is reduced for high rates, high amount of electrolyte and low sulfur loading. In addition idle periods in the cycling regiment and lower rates result in an increased degradation. We attribute this to the redox-reaction between reactive lithium and polysulfides that correlates with the cycling time, rather than cycle number.
Propensity to diabetic nephropathy (DN), retinopathy (DR), and cardiovascular disease (CVD) varies between individuals. Current biomarkers such as indicators of glycemia (HbA1c), retinal examinations, and albuminuria, cannot detect early tissue damage. HbAIc also doesn’t reflect most glycative and oxidative chemical pathways that cause complications, and studies of new biomarkers to measure their end-products are needed. This review proposes the study of advanced glycation end products (AGEs) and oxidation end-products (OPs) in long-term diabetes outcome studies. AGEs integrate the activity of glycation pathways that form dicarbonyls, while OPs reflect superoxides, hydroxyl radicals, and peroxides. We discuss using these biomarkers to predict risk of development and progression of DN, DR, and CVD, and to determine if they confer risk independently of the level of HbA1c. We also discuss methods and guidelines to document sample quality in such studies. These studies have the potential to validate unique biomarkers during the early stages of diabetes in those who are at high risk of diabetic complications. Information on basic mechanisms responsible for complications could also stimulate development of therapeutic approaches to delay or arrest them. The ultimate goal is to predict those requiring aggressive therapies during the earliest stages, when prevention or reversal of complications is still possible.
Silver nanoparticles supported on cobalt and nitrogen embedded reduced graphene oxide, Ag/Co-NGr, are synthesized by one-step hydrothermal route with remarkable catalytic activity for oxygen reduction reaction (ORR). As-synthesized electrocatalyst exhibits half-wave potential (0.82 V) comparable to commercial Pt/C (0.85 V), specific activity (0.45 mA cm−2) better than commercial Pt/C (0.35 mA cm−2) along with superior stability in alkaline environment (≈95% activity retention after 5000s compared to 80% for Pt/C). Moreover, Ag/Co-NGr is highly tolerant to methanol poisoning during ORR and delivers an excellent specific capacity of 789 mAh.g−1 Zn with energy density of 947 Wh. kg−1 at a current density of 20 mA cm−2 in a Zn-air battery. For the first time, it is proven that particle size refinement and electronic perturbation of Ag nanoparticles take place due to metal-support interactions between Ag and Co/NGr. d-band center of Ag in Ag/Co-NGr upshifts toward the Fermi level with respect to the Ag/NGr as a result of charge transfer between Ag and Co/NGr. The superior catalytic activity and excellent stability of Ag/Co-NGr is attributed to the structural and electronic modification of Ag nanoparticles by Co and N elements on graphene.
We propose a new breakthrough in realizing a practical Li–metal battery (LMB) capable of fast charging while delivering a high energy density. We used an electrolyte consisting of 1 M LiPF6 and 0.05 M lithium difluoro(oxalate)borate dissolved in a mixture of ethyl methyl carbonate and fluoroethylene carbonate to ensure the formation of a stable and robust solid electrolyte interphase (SEI) layer on the anode surface. Pretreatment of the Li–metal anode with LiNO3 adds a prior Li2O-rich SEI layer that provides the required mechanical strength to prevent premature SEI layer breakdown. An Al-doped full-concentration-gradient Li[Ni0.75Co0.10Mn0.15]O2 cathode provides the necessary cycling stability at a high cathode loading. By integrating these components, we produced an LMB that allowed a high areal capacity of 4.1 mA h cm−2 with an unprecedented cycling stability over 300 cycles at a high current density of 3.6 mA cm−2 (full charge–discharge in 2 h). We believe that the findings presented herein provide new perspectives for the development of practical LMBs that satisfy the capacity and charging rate requirements for future electric vehicles.
Closed-loop supply chain (CLSC) is a prominent concept emphasizing on both economic and environmental aspects. Since a CLSC comprises of forward and reverse supply chains, there are a variety of internal and external factors associated with its total expected profit. In a forward flow, volatility in transportation cost, holding cost, and forecasting the market's demand are the most challenging issues for decision makers, while determining the rate of returned products and efficiency in recycling the returned products are crucial parameters to predict in reverse flow. In this paper, it is aimed to develop and apply a fully fuzzy programming (FFP) method to determine the possible upper, middle, and lower ranges of profit for a multi-echelon battery CLSC with multi-components, multi-product in multi-period under imprecise information. In addition, we extend the proposed model to multi-objective to consider the green factors related to plants and battery recovery centers. Fuzzy analytic network process (Fuzzy ANP) is utilized to alter the qualitative measurements to the measurable parameters. Then, distance technique and ε-constraint method are utilized for solving the multi-objective problem. We illustrate the application of the model in Vancouver, Canada using maps.
Laboratory-size LiNi0.8Co0.15Al0.05O2/graphite lithium-ion pouch cells were cycled over 100% DOD at room temperature and 60°C in order to investigate high-temperature degradation mechanisms of this important technology. Capacity fade for the cell was correlated with that for the individual components, using electrochemical analysis of the electrodes and other diagnostic techniques. The high-temperature cell lost 65% of its initial capacity after 140 cycles at 60°C compared to only a 4% loss for the cell cycled at room temperature. Cell ohmic impedance increased significantly with a elevated temperature cycling, resulting in some of loss of capacity at the C/2 rate. However, as determined with slow rate testing of the individual electrodes, the anode retained most of its original capacity, while the cathode lost 65%, even when cycled with a fresh source of lithium. Diagnostic evaluation of cell components including X-ray diffraction (XRD), Raman, CSAFM and suggest capacity loss occurs primarily due to a rise in the impedance of the cathode, especially at the end-of-charge. The impedance rise may be caused in part by a loss of the conductive carbon at the surface of the cathode and/or by an organic film on the surface of the cathode that becomes non-ionically conductive at low lithium content.
The advent of small scale combined heat and power (CHP) systems has provided the opportunity for in-house power backup of residential-scale photovoltaic (PV) arrays. These hybrid systems enjoy a symbiotic relationship between components, but have large thermal energy wastes when operated to provide 100% of the electric load. In a novel hybrid system is proposed here of PV-trigeneration. In order to reduce waste from excess heat, an absorption chiller has been proposed to utilize the CHP-produced thermal energy for cooling of PV-CHP system. This complexity has brought forth entirely new levels of system dynamics and interaction that require numerical simulation in order to optimize system design. This paper introduces a dispatch strategy for such a system that accounts for electric, domestic hot water, space heating, and space cooling load categories. The dispatch strategy was simulated for a typical home in Vancouver and the results indicate an improvement in performance of over 50% available when a PV-CHP system also accounts for cooling. The dispatch strategy and simulation are to be used as a foundation for an optimization algorithm of such systems.
If we are to find treatments to postpone, reduce the risk of, or completely prevent the clinical onset of Alzheimer disease (AD), we need faster methods to evaluate promising preclinical AD treatments, new ways to work together in support of common goals, and a determination to expedite the initiation and performance of preclinical AD trials. In this article, we note some of the current challenges, opportunities and emerging strategies in preclinical AD treatment. We describe the Collaboration for Alzheimer's Prevention (CAP)—a convening, harmonizing and consensus-building initiative to help stakeholders advance AD prevention research with rigour, care and maximal impact—and we demonstrate the impact of CAP on the goals and design of new preclinical AD trials.
Executive functions are a set of high cognitive abilities that control and regulate other functions and behaviors and are crucial for successful adaptation. Deficits in executive functions are frequently described in developmental disorders, which are characterized by disadaptive behavior. However, executive functions are not widely examined in individuals with intellectual disability. The present study is aimed at evaluating the etiological specificity hypotheses pertaining to executive functions by comparing individuals with intellectual disability of different etiology, as Williams syndrome and Down syndrome, on different aspects of executive functions. To this aim a battery evaluating attention, short-term and working memory, planning, categorization, shifting and inhibition, was administered to 15 children, adolescents and adults with Williams syndrome, to 15 children, adolescents and adults with Down syndrome and to 16 mental-age-matched typically developing children. The two groups with intellectual disability showed impairment in a set of executive functions, as auditory sustained attention, visual selective attention, visual categorization and working memory, and preserved visual sustained attention, auditory selective attention and visual inhibition. However, a distinctive profile has been found between the two syndromic groups on other executive functions. While participants with Down syndrome were poor in shifting and verbal aspects of memory and inhibition, those with Williams syndrome were poor in planning. The specific weakness and straights on executive functions may support the etiological specificity hypothesis accounting for distinctive cognitive development syndrome-specific.
Introduction Apathy has been repeatedly highlighted as a core component of negative symptoms especially with regard to functional outcome of schizophrenia. The purpose of this study was to explore the relationships between apathy, cognitive deficits, and psychosocial functioning in chronic patients with schizophrenia. Methods Thirty-six chronic patients with schizophrenia and an equal number of matched healthy participants were assessed with the clinician version of Apathy Evaluation Scale (AES-C) along with a comprehensive battery of neuropsychological measures. Functioning was assessed with the Personal and Social Performance scale (PSP) and other symptoms were measured with the Positive and Negative Syndrome Scale and the Calgary Depression Scale for Schizophrenia. Results Apathy was strongly and specifically associated with poorer performance on executive tests in patient group. AES-C was significantly correlated with PSP total score as well as its subscales for social useful activities, personal and social relationships, and self-care. Multiple regression analysis revealed that apathy was the most robust predictor of current psychosocial functioning, accounting for 70% of the variance in functioning, independently of co-existent cognitive deficits. Moreover, executive dysfunction did not predict functional impairment, independently of the effect of apathy. Conclusion Our findings confirm that apathy has a stronger relationship to functional impairment than cognitive deficits on a cross-sectional basis in schizophrenia. Moreover, they suggest that apathy and executive dysfunction might represent different manifestations of the same syndrome, probably sharing a common neural substrate.
Using the first-principles method within the density functional theory and the generalized gradient approximation, the properties of lithium deintercalation were studied in the ternary lithium transition metal nitride Li2.5Cu0.5N. The lithium deintercalation formation energies per lithium atom were found to be between −2.72 and −4.08eV for various amounts of Li extraction. The changes in the crystal volume, the electronic structures and the changes in charge densities of the Li x Cu0.5N due to Li extractions are also presented. This study demonstrates that the extraction of lithium ions from the [Li2N] layer is easier than that from the [Li0.5Cu0.5] layer. The change in unit cell volume was less than 5% for extractions of less than 30% of the Li ions in the unit cell. However, for a higher percentage of Li extractions, the system could shrink much more remarkably. The sequence of Li deintercalation, which was based on the calculated formation energies and the ratio of volume change, also gave some insight into the amorphization phenomenon after the first charge.
Observational evidence is presented, which corroborates the hypothesis of the general presence of estuarine circulation in the Wadden Sea as put forward in a previous study (Burchard et al., 2008). Current velocity data from moored ADCPs (in the Hörnum Deep south of Sylt Island, 2002–2009) and ship cruises (in several locations in the German Wadden Sea, 2000–2008) were analysed. As a general result, the vertical current profiles above the benthic boundary layer are usually more homogeneous during flood than during ebb, with a pronounced dependence on the cross-shore horizontal density difference. This tidal asymmetry consequently must lead to a residual outflow of Wadden Sea waters in the upper part and a residual inflow of water in the lower part of the water column, thus giving a generic explanation for the obvious net import of suspended sediments from the German Bight into the Wadden Sea.
Electrodes with nanostructures offer a better avenue to accomplish high performance supercapacitors. In view of this, seaweed like nanostructures of Bi2O3 was synthesized by electrochemical anodization of bismuth film in oxalic acid electrolyte. Even though, as-anodized films were amorphous, annealing promoted the crystallinity and promoted a phase transformation from β to γ-Bi2O3 on sequential annealing. Raman spectroscopy supported the XRD results of diminishing beta-phase Bi2O3 on sequential annealing, structural distortion and phase transformation. HRSEM images displayed the Codium tomentosum seaweed like nanostructure embedded with multiple nanofibers and nanoparticles. Cyclic voltammetry exhibited a maximum specific capacitance of 331Fg−1 for β-Bi2O3 electrode. The performance of Bi2O3 electrode pseudocapacitor depends on its phase crystallinity, morphology and charge carrier density. Impedance spectral analysis revealed that the increase in the specific capacitance was mainly owing to the decrease of charge transfer resistance and the fast ion diffusion in the electrode.
Ouabain is both a cardiac glycoside used in therapy of congestive heart failure and an endogenous steroid hormone. It specifically binds to Na+, K+-ATPase (NKA) and blocks its activity. Overdose of ouabain induces retinal damage. In different species ouabain-induced retinal degeneration affects different cell types. In fish and rabbit ouabain induces retinal cell death preferentially in the ganglion cell layer and outer photoreceptor segments respectively. In rats, the pattern of NKA expression has been studied with most detail among retinal neurons. In addition, ouabain selectively destroyed some types of neurons in rodents. However, ouabain-sensitive retinal neurons remain unclear in rats. We show here that injection of ouabain into the rat vitreous body induced dramatic cell death in the inner nuclear layer (INL). The cell death was time- and dose-dependent. Ouabain-induced dying cells in the INL were TUNEL-positive. Immunohistochemistry analysis revealed that there was a significant decrease in the number of calbindin D-28K- and syntaxin-1-positive horizontal and amacrine cells in the INL of ouabain-treated rat retinas. Thus our results revealed that the horizontal and amacrine cells are the most sensitive cell types to ouabain in the retina of Sprague-Dawley rat.
An improved method for quantitative measurement of the charge transfer, finite diffusion, and ohmic overpotentials in redox flow batteries using electrochemical impedance spectroscopy is presented. The use of a pulse dampener in the hydraulic circuit enables the collection of impedance spectra at low frequencies with a peristaltic pump, allowing the measurement of finite diffusion resistances at operationally relevant flow rates. This method is used to resolve the rate-limiting processes for the V2+/V3+ redox couple on carbon felt and carbon paper electrodes in the vanadium redox flow battery. Carbon felt was limited by both charge transfer and ohmic resistance, while carbon paper was limited by charge transfer, finite diffusion, and ohmic resistances. The influences of vanadium concentration and flow field design also are quantified.
Abstract Advances in robotic technologies have enabled the creation of new powered devices that can be worn by humans to assist their movement. These robotic exoskeletons can augment human performance in healthy individuals, replace lost motor functions in individuals with disabilities, or provide automated motor practice for therapeutic rehabilitation after neurological injury. There are still many limitations that need to be overcome to create commercially successful devices, including creating a comfortable physical human–machine interface and a controller that allows fluid and smooth motions.
Reaction of Ta(NMe2)5 with 10 equivalents of 2,6-Me2C6H3SH in toluene resulted in the formation of bright red crystals of [Ta(SC6H3Me2-2,6)4(NMe2)] (1). The related reaction between Ti(NEt2)4 and 10 equivalents of ButSH in toluene afforded a mixture of two complexes, [Ti(SBut)4] (3) and [Ti(SBut)3(NEt2)] (4). X-Ray crystal structures of 1 and 4 have been determined. Vapour phase thin-film studies of compounds 1 and 3/4 revealed that 1
is not an effective tantalum sulfide precursor whereas 3/4 produced TiS2.
In order to realize new high performance electrodes for lithium-ion batteries (LIBs), the careful design of nanoarchitectures and effective hybridization of active materials are research areas of great interest. Here, we present a simple and highly controllable two-step fabrication technique, followed by a heat treatment process, for the large-scale in situ growth of 3D hierarchical tubular CuO/other metal oxides core/shell heterostructure arrays that are directly grown on Cu foam. As a proof-of-concept demonstration of the application of such 3D hierarchical tubular heterostructure arrays, the prepared tubular CuO/CoO core/shell arrays are investigated as binder- and conductive agent-free anodes for LIBs, exhibiting an impressive capacity of 1364mAhg−1 at a current density of 100mAg−1 after 50 cycles and maintaining 1140mAhg−1 after 1000 cycles at 1.0Ag−1. This excellent electrochemical performance can be attributed to the unique hollow porous architecture consisting of 3D hierarchical tubular core/shell architectures, and the effective hybridization of two electrochemically cohesive active materials. Our work shows that this material has great potential for high-energy and high-power energy storage applications.
Publisher Summary Environmental requirements actually define the requirements for interfaces between one of the environmental components appropriate to the system and an element of a system. They are, therefore, a special case of interface requirements in that sense. The environmental components are: natural, self-induced, cooperative, noncooperative, and hostile. We seek to define the environmental stresses that our system and its parts shall experience in each of these categories so that when the system is placed in service, it can withstand the combined environmental stresses placed upon it while satisfying its performance requirements. A naval aircraft's wing must be designed to withstand not only the static stresses experienced in flight because of atmospheric drag in clear air and the effects of gravity on the supported vehicle, but also for the dynamic forces experienced in conditions of wind shear, carriage and release of wing stores (including possible pyrotechnic shock during explosive separation of stores), some level of battle damage, possible overloading stresses a pilot may have to apply in tactical maneuvers, and the bone-jarring impact with an aircraft carrier deck arresting and catapult systems.