batterydata/paper-abstracts huggingface dataset:
Objective Uncertainty regarding the degree to which persons with schizophrenia may lack decision-making capacity, and what the predictors of capacity may be led us to examine the relationship between psychopathology, neurocognitive functioning, and decision-making capacity in a large sample of persons with schizophrenia at entry into a clinical trial. Method In the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) schizophrenia trial, a clinical trial sponsored by the National Institute of Mental Health designed to compare the effectiveness of antipsychotic drugs, subjects were administered the MacArthur Competence Assessment Tool-Clinical Research (MacCAT-CR) and had to demonstrate adequate decision-making capacity before randomization. The MacCAT-CR, the Positive and Negative Syndrome Scale (PANSS), and an extensive neurocognitive battery were completed for 1447 study participants. Results The neurocognitive composite score and all 5 neurocognitive subscores (verbal memory, vigilance, processing speed, reasoning, and working memory) were positive correlates of the MacCAT-CR understanding, appreciation, and reasoning scales at baseline. Higher levels of negative symptoms, but not positive symptoms, were inversely correlated with these three MacCAT-CR scales. Linear regression models of all three MacCAT-CR scales identified working memory as a predictor; negative symptoms made a small contribution to the understanding and appreciation scores. Conclusions Negative symptoms and aspects of neurocognitive functioning were correlated with decision-making capacity in this large sample of moderately ill subjects with schizophrenia. In multiple regression models predicting performance on the MacCAT-CR scales, working memory was the only consistent predictor of the components of decision-making capacity. Individuals with schizophrenia who have prominent cognitive dysfunction, especially memory impairment, may warrant particular attention when participating in research.
Strong ionic interactions in concentrated ionic liquids is shown to result in significant correlations and deviations from ideal solution behavior. We use rigorous concentrated solution theory coupled with molecular dynamics simulations to compute and explain the unusual dependence of transport properties on cation concentration in the Na + - Pyr 13 + - FSI − ionic liquid electrolyte. When accounting for intra- and inter-species correlation, beyond the commonly used uncorrelated Nernst-Einstein equation, an anomalously low and even negative transference number emerges for x NaFSI lower than 0.2. With increasing concentration the transference number monotonically increases, approaching unity, while the total conductivity decreases as the system transitions to a state resembling a single-ion solid-state electrolyte. The degree of spatial ionic association is explored further by employing unsupervised single-linkage clustering algorithm. We emphasize that strong ion-ion coupling in the electrolyte significantly impacts the trade-off between key electrolyte transport properties, and consequently governs the power density of the battery.
Amorphous nanostructured hydrated electrochemical manganese dioxide (EMD) was potentiodynamically deposited on stainless steel (SS). Electrolyte medium used for the deposition was 0.5M H2SO4 + 0.5M MnSO4·5H2O. The scan rate of deposition was varied between 50 and 200mVs−1. The EMD deposited SS electrodes were characterized by cyclic voltammetry (CV) in 0.1M Na2SO4 for electrochemical redox supercapacitors. The specific capacitance (SC) of EMD increases by increasing the scan rate of deposition. For EMD deposited at 200mVs−1, a maximum SC of 482Fg−1 was obtained from cyclic voltammetry at a scan rate of 10mVs−1. For the same electrode, a SC value of 275Fg−1 was obtained even at a high scan rate of 150mVs−1, indicating high power characteristics of the material. The SC was found to increase with the increase in thickness of EMD. Long cycle-life and stability of EMD were also demonstrated.
Li2MnO3 is an important component of the Li-rich Mn-based high-capacity cathode material for lithium ion batteries, xLi2MnO3·(1 − x)Li M′ O2 composites. Replacing Li2MnO3 with iso-structured Li2MoO3 is expected to improve the rate performance and suppress the oxygen release of the composites at high potentials due to the higher electric conductivity of Li2MoO3 and its more facile charge compensation (by Mo4+/Mo6+ redox) upon Li removal than that of Li2MnO3. As part of our series work on the Li2MoO3-based Li-rich layer structured cathode materials, this article is to study the structural and performance stability of Li2MoO3 in air. The obtained information will shed light on the development and application of xLi2MoO3·(1 − x)Li M′ O2 composite cathode materials though Li2MoO3 will not be applied as an independent cathode material.
In this essay, I argue that the work of Giorgio Agamben provides us with a theory of studious play which cuts across many of the categories that polarize educational thought. Rather than either ritualized testing or constructivist playfulness, Agamben provides a model of what he refers to as studious play—a practice which suspends the logic of both ritual and play. In order to explore this notion of studious play, I first articulate Agamben’s fleeting remarks on the topic with an important problematic found in his early, literary work: transmission. If ritual transmits cultural traditions to ensure continuity with the past, and play as constructivist invention makes such transmission impossible, then studious play transmits transmissibility itself as a pure potentiality. Studious play accomplishes this peculiar educational task by suspending without destroying traditional things: laws, signs, and so on. I end the essay with a consideration of the ontological status of suspended things, arguing that they are transformed into toys via the action of study. Finally, I give a literary example of studious play found in Robert Walser’s novel Jakob von Gunten in which the school itself is imagined to be a kind of toy.
Potential step and linear sweep voltammetry are proposed in combination for the anodic excursion peaks (AEPs) measurement of lead in sulfuric acid during cathodic scanning in the positive potential range. The overall procedure of measurement is composed of three steps. The first one is to polarize the lead electrode with negative potential, which is necessary for passivated PbSO4(O) formation. Then, the polarization potential is stepped to positive to make sure that pure Pb could be oxidized to produce PbO n intermediate. Finally, a low-rate cathodic linear sweep voltammetry measurement is conducted in a small potential range. Four AEPs have been observed without reduction of PbO2 to PbSO4, which is in confliction with the conventional understanding that AEPs would appear accompanying with a large reduction peak for PbO2 discharge. A new mechanism is therefore proposed that AEPs corresponds to the oxidation of PbO n intermediate in the cathodic scanning, so AEPs can be used to indicate the difficulty for the oxidation of Pb to PbO2, and could be applied to characterize the corrosion resistance of lead alloy grid in the positive plate of a lead-acid battery.
Mixed ionic-electronic conductors in the family of La x Sr1–x Co y Fe1–y O3–δ have been widely studied as cathode materials for solid oxide fuel cells (SOFCs). However, the long-term stability was a concern. Here we report our findings on the effect of a thin film coating of La0. 85Sr0. 15MnO3–δ (LSM) on the performance of a porous La0. 6Sr0.4Co0.2Fe0.8O3–δ (LSCF) cathode. When the thicknesses of the LSM coatings are appropriate, an LSM-coated LSCF electrode showed better stability and lower polarization (or higher activity) than the blank LSCF cathode without LSM infiltration. An anode-supported cell with an LSM-infiltrated LSCF cathode demonstrated at 825 °C a peak power density of ∼1.07 W/cm2, about 24% higher than that of the same cell without LSM infiltration (∼0.86 W/cm2). Further, the LSM coating enhanced the stability of the electrode; there was little degradation in performance for the cell with an LSM-infiltrated LSCF cathode during 100 h operation.
Unusual overcharge tolerance behavior was observed in Electrochem’s polymer lithium ion cells. The cells could be overcharged up to several times the nominal capacity without a significant increase in cell potential. Experimental studies were carried out to understand this phenomenon. Cyclic voltammograms on gelled solid polymer electrolytes indicated that this phenomenon did not originate from an oxidation–reduction shuttle mechanism. A correlation between the apparent overcharge tolerance capability and anode to cathode capacity ratio was found. This observation suggested that the observed overcharge tolerance behavior was caused by non-dendritic lithium deposition on the carbon anode surface during overcharge. It was hypothesized that this lithium deposition created some weak electronic conducting paths through which part of the overcharge current was bypassed. Results of surface analyses on both fully charged and overcharged anodes were consistent with the above hypothesis.
A major hurdle to the widespread commercialization of proton exchange membrane fuel cells (PEMFCs) is the high loading of noble metal (Pt/Pt-alloy) catalyst at the cathode, which is necessary to facilitate the inherently sluggish oxygen reduction reaction (ORR). To eliminate the use of Pt/Pt-alloy catalysts at the cathode of PEMFCs and thus significantly reduce the cost, extensive research on non-precious metal catalysts (NPMCs) has been carried out over the past decade. Major advances in improving the ORR activity of NPMCs, particularly Fe- and Co-based NPMCs, have elevated these materials to a level at which they can start to be considered as potential alternatives to Pt/Pt-alloy catalysts. Unfortunately, the stability (performance loss following galvanostatic experiments) of these materials is currently unacceptably low and the durability (performance loss following voltage cycling) remains uncertain. The three primary mechanisms of instability are: (a) Leaching of the metal site, (b) Oxidative attack by H2O2, and (c) Protonation followed by possible anion adsorption of the active site. While (a) has largely been solved, further work is required to understand and prevent losses from (b) and/or (c). Thus, this review is focused on historical progress in (and possible future strategies for) improving the stability/durability of NPMCs.
This essay’s principal objective is to examine how, when confronted with a case of possible criminal poisoning, early nineteenth-century English toxicologists sought to generate and to represent their evidence in the courtroom. Its contention is that in both these activities toxicologists were inextricably engaged in a complex communicative exercise. On the one hand, they distanced themselves from the instabilities of language, styling themselves as testifiers to fact alone. But at the same time, they saw themselves as deeply implicated in the difficulties of forging a coherent signifying system out of a disparate collection of signs that in themselves bore no intrinsic meaning. The analysis has three main components: first, to suggest why criminal poisoning featured so prominently in the burgeoning legal literature on evidence which provided the framework for expert testimony in English courts; next, to show that the scientific evidence offered by toxicologists in poisoning cases can be usefully understood as a form of (unstable) language; and finally, to suggest that this recourse to signs informed the toxicologist’s encounter with another type of courtroom expert—the legal advocate—who was equally (though differently) interested in manipulating signs in order to construct (and deconstruct) legally sanctioned proof.
Si/TiC nanocomposite anode was synthesized by a surface sol–gel method in combination with a following heat-treatment process. Through this process, nanosized Si was homogeneously distributed in a titanium carbide matrix. The electrochemically less active TiC working as a buffer matrix successfully prevented Si from cracking/crumbling during the charging/discharging process. The interspaces in the Si/TiC nanocomposite could offer convenient channels for Li ions to react with active Si. The Si/TiC composite exhibited a reversible charge/discharge capacity of about 1000mAhg−1 with average discharge capacity fading of 1.8mAhg−1 (0.18%) from 2nd to 100th cycle, indicating its excellent cyclability when used as anode materials for lithium-ion batteries.
Single-crystal ZnO nanorod/amorphous and nanoporous metal oxide shell composites were facilely prepared by electrochemical deposition and tested as promising electrode materials for supercapacitor applications.
Decreasing electric grid reliability in the US, along with increasing severe weather events, have greatly increased interest in resilient energy systems. Few studies have included the value of resilience when sizing PV and Battery Energy Storage Systems (BESS), and none have included the cost to island a PV and BESS, grid-connected costs and benefits, and the value of resilience. This work presents a novel method for incorporating the value of resilience provided by a PV and BESS into a techno-economic optimization model. Including the value of resilience in the design of a cost-optimal PV and BESS generally increases the system capacities, and in some cases makes a system economical where it was not before. For example, for a large hotel in Anaheim, CA no system is economical without resilience valued; however, with a $5317/hr value of resilience a 363 kW and 60 kWh solar and BESS provides a net present value of $50,000. Lastly, we discuss the effect of the ”islandable premium”, which must be balanced against the benefits from serving critical loads during outages. Case studies show that the islandable premium can vary widely, which highlights the necessity for case-by-case solutions in a rapidly developing market.
Intercalation and conversion are two of the most popular forms of lithium (Li) or sodium (Na) storage. Conversion reactions usually involve transference of more than one electron. Therefore, the electrode materials that store Li- and Na-ions by way of such reactions theoretically deliver specific capacities a few times higher than those of the intercalation materials. Intercalation and conversion reactions can occur in sequence upon Na storage in MoS2, but the reversibility of the latter upon Na extraction is still controversial. In this article, we clarify that the conversion reaction of nano-MoS2 can be reversible in a carbon matrix and the extent of reversibility is highly dependent on the dynamic properties of the composite. In addition, hexagonal NaMoS2 is recognized as a new phase in the early stage of Na extraction from the reduction products of MoS2, Mo+Na2S, on the basis of high-resolution transmission electron microscopy (HRTEM) characterization and first-principles calculations. These findings enrich the understanding of reaction mechanism of MoS2 upon Na storage and removal and are helpful to the design and applications of the transition metal sulfides.
Anode-free lithium metal cells store 60% more energy per volume than conventional lithium-ion cells. Such high energy density can increase the range of electric vehicles by approximately 280 km or even enable electrified urban aviation. However, these cells tend to experience rapid capacity loss and short cycle life. Furthermore, safety issues concerning metallic lithium often remain unaddressed in the literature. Recently, we demonstrated long-lifetime anode-free cells using a dual-salt carbonate electrolyte. Here we characterize the degradation of anode-free cells with this lean (2.6 g Ah−1) liquid electrolyte. We observe deterioration of the pristine lithium morphology using scanning electron microscopy and X-ray tomography, and diagnose the cause as electrolyte degradation and depletion using nuclear magnetic resonance spectroscopy and ultrasonic transmission mapping. For the safety characterization tests, we measure the cell temperature during nail penetration. Finally, we use the insights gained in this work to develop an optimized electrolyte, extending the lifetime of anode-free cells to 200 cycles.
The interfacial impedance between PVDF/HFP-based electrolytes and lithium metal continues to increase and attains a delicate kinetic equilibrium upon prolonged storage. The graphite anode, on the other hand, is found to remain inert towards the electrolytes. Its interfacial impedance does not vary with increasing storage time or in the presence of different lithium salts. In addition, it is found that the impedance of a Li–C half-cell consists of the impedances of two interfaces and is therefore often mistakenly used in the interpretation of the behaviour of a single carbon electrode. Thus, a three-electrode impedance study is required. It is found that an inductive loop appears in the low-frequency region of the impedance spectrum of a carbon electrode immediately after the first lithium-intercalation step, which probably implies that an adsorption–desorption phenomenon might exist at the interface. Moreover, another inductive effect, which arises from the connecting leads, also appears in the high-frequency region. Finally, the cathode is found to be the major source of cell impedance and increases with increasing cycle number.
Electrospun ceramic oxide fibers find myriad uses as energy materials such as in battery electrodes and vanadium oxides are one such family of materials. In this study, the structural and energy storage properties of electrospun vanadium pentoxide are compared to approximately 10 at% barium and titanium-doped equivalents. The vanadium pentoxide was doped in order to improve its electrochemical performance. The materials are characterised using powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller measurements, transmission electron microscopy and potentiostatic and galvanostatic analysis. X-ray diffraction analysis showed that each dopant has a critical effect on lattice distortions whilst showing no influence over the overall crystal structure, which is unusual for such large dopant amounts. The doped materials show better cyclability and higher efficiencies than the pure equivalent. Ex-situ X-ray diffraction measurements show detrimental phase changes within undoped V2O5 whereas the titanium-doped V2O5 predominantly remains as α-V2O5 after the first cycle.
Interconnected MnO2 nanoﬂakes supported by 3D nanostructured stainless steel (SS) plates are prepared by a facile hydrothermal synthesis. The resultant architecture is used as binder-free anodes of lithium ion batteries. Cyclic voltammetry analysis is conducted to distinguish the reactions between lithium ions and the active material at various discharge-charge potentials. Galvanostatic battery testing shows that the representative electrode exhibits a reversible capacity up to 1387.1mAhg−1 at a current rate of 0.2C after 100 cycles and a capacity higher than 492.9mAhg−1 at a rate of 5C. Such an excellent cycling performance, better rate capability and high capacity indicate that the simply etched 3D SS plate is a promising nanostructured current collector.
The oxidation of thiocyanate by iron(V) (Fe(V)) was studied as a function of pH in alkaline solutions by a premix pulse radiolysis technique. The rates decrease with an increase in pH. The rate law for the oxidation of SCN− by Fe(V) was obtained as −d[Fe(V)]/dt = k 10{[H+]2/([H+]2 + K 2[H+]+ K 2 K 3)}[Fe(V)][SCN−], where k 10 =5.72±0.19×106 M−1 s−1, pK 2 =7.2, and pK 3 =10.1. The reaction precedes via a two-electron oxidation, which converts Fe(V) to Fe(III). Thiocyanate reacts approximately 103× faster with iron(V) than does with iron(VI).
Polyacene (PAS) coated self-assembled porous micro-spherical LiFePO4 cathode material is successfully synthesized by spray drying method. The crystal structure of the sample is examined by X-ray diffraction (XRD). The micro-spherical morphology with porous structure is observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical properties are investigated via galvanostatic charge-discharge experiments and electrochemical impedance spectroscopy (EIS) analysis. The material exhibits a high lithium ion diffusion coefficient about 10−12 cm2 S−1, excellent electrochemical properties and good cyclability. The initial discharge capacity is as high as 168mAh/g at 0.1C rate, and the capacity retention is approximately 100% after 100 cycles at 1C rate, almost no capacity fading. All demonstrate that self-assembled micro-spherical particles with nano primary particles and porous structure are benefit to improve the electrochemical performance of cathode materials.
Zinc nickel flow battery is one of the most promising energy storage technologies for intermittently renewable solar and wind power. However, unpaired coulombic efficiency of nickel hydroxide cathode and zinc anode causes zinc accumulation in practical operation, which shortens the cycle life and impedes the commercialization of the battery. Here, we induce an additional O2/OH− redox couple integrated with NiOOH/Ni(OH)2 as cathode energy storage materials. Benefit from the new reaction mechanism of the hybrid cathode, deposited zinc upon charge can be fully consumed during discharge, which completely avoids zinc accumulation issue. The new designed battery vigorously operates for more than 1100 h with negligible performance degradation, while the energy efficiency of pristine zinc-nickel flow battery dramatically reduces after 440 h. More importantly, the specific capacity of the cathode synchronously increases by 2.5 times and thereby the energy density. This system dexterously integrates dual redox couples into one hybrid unit at cathode complementing advantages of one another, demonstrating a broader method to solve the problem of unpaired coulombic efficiency in zinc based flow batteries.
Redox flow batteries (RFB) provide efficient storage of renewable energy facilitating sustainable energy supply. Among various RFB, the vanadium cerium battery is distinguished with large storage potential and without phase transition during the redox reactions. Herein, a two-dimensional model of a slice of the cell in a vanadium cerium redox flow battery is developed for the first time. Electrochemical characterization of both the V(II)/V(III) and Ce(III)/Ce(IV) electrochemical systems in mixed acid media is conducted to obtain the key parameters of the model. The data obtained from the simulations is then validated against the results of real flow battery experiments exhibiting a good agreement. With the perspective of state-of-the-art design in RFB system management for future large-scale systems, state of charge deviation and flow efficiency, are introduced as innovative measures of lifetime and energy density of the battery. The illustrated effect of several parameters involved in the proposed model provides direction toward optimum design of RFB systems.