batterydata/paper-abstracts huggingface dataset:
It is well known that when the carbon/LiMn2O4-based cathode battery was operated at elevated temperatures, the severe capacity loss occurred in following cycles. As we recently described, the capacity loss is mainly due to the degradation on the carbon anode side caused by the deposition of manganese at the carbon followed by the irreversible decomposition at the graphite/deposited Mn/electrolyte interface. It was found that inorganic additives in electrolyte, such as LiI, LiBr, and NH4I, effectively suppressed the degradation of graphite anode to improve the battery performance. In case of LiI and LiBr, the irreversible reaction at the Mn/electrolyte interface was suppressed by specific adsorption of iodide or bromide anions on the metallic Mn surface. Further, the reduction of Mn(II) would be suppressed by adding NH4I into electrolyte which could be due to the formation of a stable amine complex of Mn(II).
Long-term survival of childhood leukemia has become a reality with treatment advancement; hence, the need to assess the survivors’ health-related quality of life (HRQL) is essential. Although a growing number of Western studies have documented the considerable impact of diagnosis and treatment on HRQL in pediatric leukemia survivors, little finding has been reported in non-Western developing countries.
Résumé Objectif. – Identifier les échelles globales et spécifiques d'évaluation des incapacités et de la qualité de vie des patients présentant des troubles cognitifs. Matériel et méthodes. – Une revue systématique de la littérature a été effectuée sur Medline en utilisant les mots clés : assessment, evaluation, deficiency, disability, disadvantage, handicap, quality of life, scale, index, questionnaire, CIDIH-1, CIDIH-2. Pour chaque mot clé précédent, une recherche a été faite pour les déficits cognitifs suivants : troubles des fonctions exécutives, troubles de mémoire, troubles de l'attention, négligence unilatérale, apraxie, aphasie, agnosie, troubles émotionnels. L'analyse a pris en compte les échelles validées en distinguant celles évaluant l'incapacité de celles mesurant le handicap et la qualité de vie. Résultats. – Pour l'évaluation de l'incapacité, il existe deux catégories d'échelles : des échelles globales et des échelles spécifiques. Celles-ci existent actuellement pour les troubles des fonctions exécutives, les troubles de mémoire et d'attention, la négligence unilatérale, l'aphasie et les troubles émotionnels. Des versions françaises et des épreuves francophones originales ont été validées dans ces domaines. Il n'existe pas d'outil spécifique en cas d'apraxie ou d'agnosie isolée. Pour la mesure du handicap et de la qualité de vie, il existe principalement des échelles génériques et des échelles spécifiques d'une pathologie (accident vasculaire cérébral, traumatisme crânien, sclérose multiloculaire). L'aphasie est une déficience pour laquelle sont proposés des outils spécifiques d'évaluation de l'incapacité ainsi que de la qualité de vie. Conclusion. – Les résultats précédents montrent l'impact qu'a eu le cadre conceptuel proposé par la CIDIH-1 dans l'évaluation des conséquences fonctionnelles des troubles cognitifs. Cette démarche se heurte souvent à l'absence de modèle explicatif des troubles et à la difficulté à évaluer les conséquences de l'environnement et de l'anosognosie sur les troubles.
In this study, the clinical profile of Hindi-speaking stroke patients with aphasia from northern India has been investigated. We examined the interactional effect between age and gender with aphasia type in 97 Hindi-speaking right-handed individuals, the majority of them with a confirmed diagnosis of a cerebrovascular accident. The subjects included in the study ranged from 3 weeks to two years post-onset with a diagnosis of a common classical aphasia (Broca's, Wernicke's, anomic, global, conduction, and transcortical) types involving both males and females. Also examined was the interaction between literacy and aphasia type since the subjects had varied exposures to education (total illiteracy to professional/university education). While the data reported here about Hindi-speaking aphasics are relatively in agreement with the age-aphasia type patterns discussed in western countries, nonetheless some differences were also observed. The mean age of Indian patients with aphasia was significantly lower. Also, in addition to some gender and literacy related differences, an outstanding difference was that many clinical symptoms that are known to co-occur with aphasia were not readily reported by subjects with stroke.
A new type of integrated power fiber that incorporates a dye-sensitized solar cell (DSSC) and a supercapacitor (SC), which can be used for energy conversation and storage, was introduced for the first time. A stainless steel wire coated with polyaniline via anodic deposition is jointly used as the electrode of the fiber DSSC and fiber SC. The overall energy conversion efficiency of the integrated power fiber is as high as 2.1%. Compared with traditional integrated power systems, our integrated power fiber is lightweight, flexible, inexpensive, suitable for special applications, and capable of integrating with cloth.
Abstract Formation processes: Processes of formation of the negative plates proceed in two stages. In first stage, PbO and basic lead sulfates are partly reduced to Pb and partly react with H2SO4 to form PbSO4. The solution in the plate pores is neutral to alkaline. During the second formation stage, PbSO4 is reduced to Pb and the pore solution becomes acidic. Formation starts on the grid surface yielding a gray (Pb+PbSO4) zone. This zone then grows along the two surfaces of the plate. After covering the whole plate surface, the (Pb+PbSO4) zones grow towards the plate interior until the entire plate volume is formed. Structure of negative active material (NAM): The structure of the lead active material formed during the first stage comprises a network (skeleton) of bonded particles of irregular shape. During the second formation stage, small Pb crystals are formed on the skeleton surface. These crystals take part in the discharge process and build the energetic structure of NAM that determines the capacity of the plate. The ratio between the skeleton and energetic structures has an impact on the performance of the negative plates. Effect of expander on the formation processes and on NAM structure: Lignosulfonate contributes to the formation of the energetic structure of NAM built of small Pb particles providing high active mass surface. The size of the Pb particles depends on the type and amount of expander used. The stability of the energetic structure depends on the expander. At temperatures higher than 60°C, expanders disintegrate and the plates lose capacity.
Unlike common oxovanadium(IV) complexes with tetradentate Schiff base ligands, [N,N′-(2,2-dimethyl-1,3-propylene)bis(salicylideneiminato)]oxovanadium(IV) ([VO(salptn)]) was easily oxidized by dioxygen in aqueous CH3CN. The [VO(salptn)]–O2 stoichiometry was 4:1. This particular reactivity comes from the preference of [VO(salptn)] to be six-coordinate rather than five, that drives the formation of an O2-complex. The structure of the oxidized product, [VO(salptn)]OH, was characterized by single-crystal X-ray diffraction. The results are consistent with a mechanism involving an attack of O2 at the vanadium(IV) center, followed by the formation of the μ-dioxo dimmer as a transient species and the subsequent splitting of the O–O bond by hydrolysis to yield [VO(salptn)]OH.
This article presents the results of experimental and theoretical studies of energy losses owing to the internal resistance of vanadium redox flow batteries (VRFBs). A dependence of the internal cell resistance (ICR) on the electric current was measured and calculated. During the cyclic operation of a test battery, the internal resistance was halved by increasing the electric current from 3 A to 9 A. This is due to a strongly non-linear dependence of an over-potential of the electrochemical reactions on the current density. However, the energy efficiency does not increase due to a squared dependence of the energy losses on the increasing electric current. The energy efficiency of the test battery versus the electric current was measured and simulated. The deviation between the simulation results and experimental data is less than ±3.5%.
In this article, we report the use of nanochannel arrays as supports for proton exchange membranes in microfluidic fuel cells. The proposed design has been demonstrated by fabricating a sodium silicate based sol–gel structure within such an array bridging two microchannels containing the fuel (HCOOH) and the oxidant (KMnO4) streams. A voltage was generated in this system by bringing two platinum electrodes in contact with these solutions and then connecting them through an external circuitry. With this current design, we have been able to generate an open circuit potential of 1.31V and a maximum current of 31.2μA at 25°C.
A conductive adhesive layer (CAL) composed of graphene/polyvinylidene fluoride (PVdF) composite is applied between a current collector and an active material layer to enhance the electrochemical performance of lithium ion battery anodes. Graphene content in the CAL varies in the range of 0–3 wt% relative to PVdF. The CAL significantly improves the cyclic performance of both graphite and silicon/graphite electrodes by increasing the adhesion strength of the electrodes. An increase in graphene content increases electronic conductivity but decreases lithium ion transfer of the CAL film. Therefore, a CAL containing a relatively small amount of graphene (1 wt%) is more favorable to highly conductive graphite electrodes, whereas a CAL containing 2 or 3 wt% graphene shows better electrochemical performance in the case of relatively low conductive silicon/graphite electrodes.
The calorimetric properties of a novel miniaturized ceramic differential scanning calorimeter device (MC-DSC) with integrated heater and crucible are presented. All features of a conventional DSC apparatus (including oven) are integrated into this DSC device of the size 11 mm × 39 mm × 1.5 mm. The MC-DSC device is suitable for one-way use, since it is fully manufactured in the low-cost planar low temperature co-fired ceramics technology. First characterization of this device is performed using indium, tin and zinc samples. The calorimetric sensitivity at 156.6 °C is 0.24 J/°C s. It depends linearly on temperature in the range of at least 150 °C and 420 °C. The calorimetric sensitivity is constant up to an enthalpy of fusion of at least ΔH = 750 mJ (at 156.6 °C). The thermal analysis of indium in direct contact to the crucible of the chip even reveals a constant calorimetric sensitivity up to an enthalpy of fusion of at least ΔH = 1000 mJ. The repeatability of the peak area is within ±0.3% (11 mg indium, 10 measurements). The thermal resolution determined using 4,4′-azoxyanisole under TAWN test conditions is 0.12 (i.e. 88%). The thermal resolution determined using Dotriacontane is 0.58 (i.e. 42%). Simulations of a strongly simplified finite element model of the MC-DSC device agree well with measurement results allowing a model-based prediction of its basic characteristics.
The electrochemical properties of the polymer electrolytes based on poly(vinyl chloride)/poly(methyl methacrylate) blend with micro-pore structure have been investigated. The introduction of poly(methyl methacrylate) (PMMA) into the poly(vinyl chloride) (PVC) matrix enhanced compatibility between the polymer matrix and the liquid electrolyte (EC/DMC/LiClO4). The addition of silica into the polymer blend generated a micro-pore structure in the polymer matrix and increased the uptake amount of the liquid electrolyte. The ion conductivity of the polymer electrolyte was increased with the increase in the PMMA content in the blend and the room temperature ion conductivity of the polymer electrolyte based on PVC/PMMA (5:5, w/w) blend was 1.1×10−3 S/cm. The charge–discharge behavior of the unit cell was also investigated.
This paper presents a control strategy for hybrid power source based on fuel cell (FC) as the main power source and battery/supercapacitor (SC) as auxiliary power sources for electric vehicle application. In this study, a Battery and SC are auxiliary devices associated with the FC to ensure the power reversibility in the drive train. The FC, Battery, and SC are connected to the DC bus throughout an interleaved boost converter (IBC) and two interleaved bidirectional converters (IBDC) respectively. The paper proposes the control strategy based on power frequency splitting to avoid FC starvation problem, reduce the battery stress and improve the fuel economy of FC. The detail of the control strategy is presented and an Energetic Macroscopic Representation (EMR) is used to develop the whole system. The simulation results are presented to validate the proposed method in the hybrid system.
Two-dimensional MoS2 shows great potential for effective Li storage due to its good thermal and chemical stability, high theoretical capacity, and experimental accessibility. However, the poor electrical conductivity and the restacking tendency significantly restrict its applications to lithium ion batteries (LIBs). To overcome these problems, we introduced reduced graphene oxides (rGO) to the intercalation-exfoliation preparation process of few-layered MoS2 and obtained layer-by-layer MoS2/rGO hybrids. With the addition of rGO, the restacking of MoS2 layers was apparently inhibited, and MoS2 with 1∼3 layers was obtained in the composite. Due to the positive role of rGO, MoS2/rGO hybrids exhibited highly enhanced cyclic stability and high-rate performances as LIB anodes in comparison with bare MoS2 layers or bulk MoS2. Moreover, the experimental results were well interpreted through density functional theory computations.
Fundamental understanding of ionic transport is critical to developing rechargeable batteries with high performance. While various techniques have been developed to characterize ionic transport in solid battery electrodes, little has been done to visualize ion movement in the liquid electrolyte, since it is difficult to realize high temporal, spatial and concentration resolutions simultaneously in liquids. Fluorescence imaging has the capability to detect ions in liquid with high resolution (< 1s, < 300nm and < 1M), and it is widely used in biomedical studies. However, it has been rarely applied to battery studies. Here we show that using an ion indicator, the dissolution of trace amount of Mn from LiMn2O4, a common Li-ion battery cathode material, can be visualized under a fluorescence microscope. Moreover, important physical parameters, such as the dissolution rate and ionic diffusivity, can be extracted quantitatively from the fluorescence images. These results also show that nanoscale Al2O3 coating can effectively suppress Mn dissolution, which is consistent with past studies. This study demonstrates the capability of fluorescence-imaging based techniques for battery studies, which could help gain more insight on the behavior of ions in battery systems and develop better battery materials.
Frequent pressure transients are identified as the cause of block failures in many unlined hydropower tunnels. The primary design objective of such tunnels is to prevent hydraulic jacking at design static pressure and mass oscillation but neglects the effect of short transients, i.e., water hammer. The issue has not been studied from the perspective of hydro-mechanical interactions due to frequent pore pressure changes in the rock mass. This article mainly focuses on the effect of pressure transients at different static heads, or different effective normal stresses across the joints and the effect of time period of pressure transient. Further, the change in such behaviour due to different mechanical properties of rock joints, such as stiffness, friction angle and dilation, is investigated. Numerical simulations of observed pore pressure response in the rock mass during a pressure transient are carried out using distinct element code 3DEC. The results show that relative joint deformation due to short pressure transients are the highest when joint normal stresses are 1.5–2.5 times higher than static water pressure in the tunnel and thus the vulnerability to weakening of such joints by hydraulic fatigue is higher. Further, results show that water hammers can travel up to 4 m into the rock mass even in stiff joint conditions and sufficiently high normal stresses. Results further indicate that the hydraulic impact due to water hammer is smaller as compared to mass oscillation. It is concluded that water hammers, wherever applicable along the waterway, can still contribute to hydraulic fatigue of rock joints in addition to the effect of mass oscillation and cannot be neglected when pressure transients occur frequently. Tunnel filling/dewatering and mass oscillations cause macroscopic joint displacements or block movements over long-term operation which is the major cause of block falls in unlined pressure tunnels.
This paper demonstrated reusing electric vehicle traction lithium ion batteries for solar energy time shifting and demand side management in a single family house. Batteries retired from electric vehicle usage retain 70% to 80% of their capacity and can be re-purposed as stationary storage system at reduced cost. However, they have mismatched aging conditions and unbalanced state-of-charge levels. Under typical series-parallel connection, the cells in a pack are prone to over charging or discharging due to deviated cycling conditions and misestimated states. The demonstrated battery management system included an extended Kalman filter based states estimator, enhanced current shunting, and protective circuitry to ensure system safety. One novel contribution was the introduction of a worst-difference state-of-charge estimation scheme for the battery pack, which places more computational resources on the battery cell of the worst health. The scheme provided satisfactory overall estimation accuracy and offered a method to optimize computational cost when large number of battery cells was integrated. In addition, a function was proposed to indicate the overall states of the entire energy storage system by aggregating the states of the battery cells within. Therefore, the energy management unit was able to dispatch the battery assembly as a unified pack. Three decision-table-based control strategies were demonstrated with objectives to maximize economic benefits, minimize grid energy consumption, or a balance of both. The data obtained from the demonstrating system located in Davis, CA showed that the battery energy storage system was able to successfully mitigate solar intermittency and energy demand fluctuation by charging from excess solar energy and discharging during the period of peak demand. It reduced daily grid energy consumption by 64%–100% and significantly improved solar penetration.
A 10-element, 950m long, vertical hydrophone array based on fiber-optic data transmission has been developed primarily for studying the beam pattern from deep diving cetaceans emitting sonar pulses. The array elements have a configurable sampling rate and resolution with a maximum signal bandwidth of 90kHz and a maximum dynamic range of 133dB. The array has been deployed from a 14m ketch with a crew of four. In the course of the development a number of mechanical and electrical problems have been solved.
Understanding how regulatory networks initiate, maintain and synchronise transcriptional states remains a fundamental goal of developmental biology. Complex patterns of spatio-temporal gene expression are generated through the combined inputs of signalling and transcriptional networks converging on cis-regulatory modules (CRMs). Detailed studies in Drosophila, using transgenic reporter assays and mutagenesis analysis, have dissected the regulatory logic of a number of CRMs. These data have recently been complemented by genome-wide maps of transcription factor binding, revealing an unprecedented view of CRM occupancy and network complexity. The synthesis of data for three well-characterised Drosophila developmental networks reveals emerging themes at both a CRM and a cis-regulatory network level.
In order to fully excavate Ti3C2Tx's electrochemical energy storage capability, a combination of cold pressing and annealing treatment is developed to fabricate free-standing Ti3C2Tx MXene films featuring well-defined film structure, planar macropores, in-plane defects and expanded interlayer spacing. The rational construction of microreactors between Ti3C2Tx nanosheets by cold pressing can assist the formation of the planar macropores and in-plane defects of Ti3C2Tx nanosheets under the annealing conditions, whereas the annealing process could regulate the functional groups of Ti3C2Tx nanosheets to significantly expand their interlayer spacing. These structural advantages not only can prevent self-restacking of Ti3C2Tx nanosheets, but also can increase the ion and electrolyte diffusion as well as the utilization of electrochemically active sites. The as-prepared PF-Ti3C2Tx-500, pre-pressed at 6 MPa followed by an annealing treatment at 500 °C in H2/Ar, exhibits excellent characteristics as the lithium storage anode, such as an enhanced initial Coulombic efficiency (CE) of 77.3%, a high areal capacity (2.22 mA h cm−2 at 7.52 mg cm−2 for 500 cycles), and stable long cycling performance. This work demonstrates the important role of microstructure manipulation of Ti3C2Tx MXene on their electrochemical performance and can guide future work on designing high-performance MXene-based materials for energy storage applications.
Over the last 30 years, phase change fibers (PCFs) have been extensively investigated and applied as high-performance nonwoven fabrics and coatings. As a prospective renewable and clean material, PCFs with micro-scale have been successfully prepared by melt/wet spinning for applications in thermal energy storage (TES) and temperature regulation. With the development of fiber manufacturing techniques, e.g. electrospinning, ultrafine PCFs have been exploited and investigated in the last decade. This paper considers the state of investigations and developments in ultrafine (submicro-scale) PCFs by electrospinning technique since 2006. Electrospun ultrafine PCFs individually using long-chain aliphatic hydrocarbons (and paraffin waxes), polyethylene glycol, fatty acids (and their eutectics), and other solid-liquid phase change materials (PCMs) as latent heat storage (LHS) component are reviewed. The relationship between morphology, composition, and thermal properties are discussed for providing guidance for fabricating appropriate ultrafine PCFs with desired thermophysical properties for various applications. The further challenges and opportunities of electrospun ultrafine PCFs for TES and other applications are also discussed.
MgFe2O4 (MFO) was prepared by a simple coprecipitation method followed by subsequently calcining at 600°C, and carbon-coated MFO (MFO/C) was obtained at 550°C using pyrrole as carbon source. The MFO/C used as anode material for rechargeable lithium-ion battery delivers a reversible capacity of 744.0mAhg−1 after 160 cycles at a current density of 100mAg−1, while the carbon-coated Fe3O4 (FO/C) prepared under the same condition exhibits a gradually declined capacity to 476.7mAhg−1 after cycling 95 times. The reversible capacities of MFO/C at the rates of 200, 400, 800, 1600, 3200, 6400mAg−1 are 612.7, 570.5, 529.5, 466.6, 355.6, and 216.9mAhg−1, also much higher than those of FO/C measured at the corresponding rates. The excellent electrochemical performance of MFO/C is associated with the smaller grain size of MFO, the nitrogen-doped carbon coating, the formation of MgO as a dispersant during charging/discharging to prevent Fe and its oxides from agglomeration and to buffer large volume change.