batterydata/paper-abstracts huggingface dataset:
Practical methods and metrics are needed to assist battery development and end-user communities in the area of battery aging, in particular, understanding capacity loss in Li-ion cells. Tools are sought that offer both diagnostic and prognostic benefits, while minimizing the need for prolonged testing or undue commitment of tangible resources. Based on a chemical engineering batch reactor approach to cell aging, this work is a move in the direction to meet such needs. Capacity loss is interpreted by a combination of sigmoidal rate expressions, having physically-meaningful parameters, which cover chief mechanisms that affect loss of available lithium and loss of active host material. A lithium source term is also accommodated by the modeling approach. Development is shown to identify reversible and irreversible capacity loss contributions, as well as calculate molar-based terms for lithium and active sites, and how these change over time due to cell aging. The method is demonstrated on NCA/graphite cell chemistries, where conditions of cycle-life, calendar-life, and temperature are considered. The resultant capability adds value toward deepening our understanding of aging contributions that impact capacity, and provides a foundation for improving Li-ion cell design and management through diagnostic and predictive elements.
This paper proposes modeling of abnormal cell overheating caused by internal short circuit in a cell of a Li-ion battery string by augmenting the cell state space model with unknown input disturbance. Furthermore, with minimum number of temperature sensors, in order to identify which of the cells in the string is experiencing the abnormal overheating, a multiple model estimator (MME) is used. Simulation results demonstrate that the proposed MME can detect the abnormally overheating cell as well as quickly detect that an abnormal overheating event occurred in the battery string.
Si@C@CNT@C composite is prepared by preliminary low-pressure forming Si@C and Si@C@CNT precursors from Si powder. After pyrolysis from glucose, acetylene and pitch, Si@C@CNT@C shows a spherical multi-phase composite structure. By using as lithium storage material, Si@C@CNT@C shows an initial discharge capacity of 620.5mAhg−1 with an initial coulombic efficiency of 82.2%. After 60 cycles, this spherical sample can maintain a reversible capacity of 563.5mAhg−1 at 100mAg−1, corresponding to a capacity retention of 90.8%. For comparison, the reversible capacities for Si powder, Si@C and Si@C@CNT are 10.9, 380.3 and 494.6mAhg−1, respectively. Even cycled at 400mAg−1, Si@C@CNT@C can deliver a reversible lithium storage capacity of 389.2mAhg−1. It indicates that spherical Si@C@CNT@C can be used as a high performance anode material for lithium-ion batteries.
Developing earth abundant and highly active electrocatalysts to overcome the sluggish oxygen reduction kinetics is one of the key toward the practical applications of air batteries with economic efficiency and high energy density. Herein, a shape-controlled synthesis of mullite SmMn2O5 is achieved through a surfactant-free one-step hydrothermal method. SmMn2O5 nanoparticles (SmMn2O5-NPs) and nanorods (SmMn2O5-NRs) are successfully synthesized and in half-cell tests, SmMn2O5-NRs perform enhanced oxygen reduction activity relative to SmMn2O5-NPs in terms of a more positive half-wave potential and reduced peroxide yield. Importantly, rechargeable zinc-air batteries constructed with SmMn2O5-NRs exhibit not only higher peak power density (217 mW cm−2) over commercial Pt/C catalyst (190 mW cm−2) but also excellent cycling stability during long-term charging-discharging test over 170 h. The facile synthesis of SmMn2O5-NRs together with the remarkable electrocatalytic performance endows mullite SmMn2O5 with great promise in replacing the precious metal as future catalysts for air batteries.
A Ni3Sn4 intermetallic compound has been prepared and tested as a new type of anode material. The results show that this compound may be cycled in a lithium cell with a reversible capacity of about 250mAhg−1. This feature, combined with the low cost and the compatibility with the environment, makes Ni3Sn4 a material of interest for practical applications.
As an alternative catalyst to replace the expensive platinum-based catalysts for oxygen reduction reaction (ORR) in both proton exchange membrane (PEM) fuel cells and metal–air batteries, tetra methoxyphenyl porphyrin cobalt complex, CoTMPP, has drawn much attention in the areas of ORR catalyst synthesis and characterization. In the present work, CoTMPP is investigated at varying temperatures of pyrolysis, ranging from 410 to 810°C, to determine the optimal temperature of pyrolysis to produce catalysts with desirable properties. Carbon supported pyrolyzed CoTMPP catalyst (CoTMPP/C) was assessed using X-ray diffraction and Raman, a number of varied electrochemical tests, as well as a single cell test. Through these, it has been found that the CoTMPP/C, pyrolyzed at 410°C, demonstrates superior catalytic activity towards ORR, and has a higher fuel cell performance than the catalysts pyrolyzed at 800°C, the industry standard pyrolysis temperature. This paper also utilizes scanning auger microscopy (SAM) to accredit the origin of the increased activity to the bond N–C(O), which plays a major role in catalysis and is decomposed at higher temperatures.
Mental health challenges (including mood, anxiety, and behavioral disorders) affect up to one-fifth of adolescents ages 13–18. Although these disorders are associated with impairments in psychological, academic, social, and family domains, they are often left untreated. Schools have great potential to address this service-underutilization gap by identifying those students at risk through mental health screening tools and by providing treatment at no cost for students. However, at the secondary level, school personnel partly expect high school students to initiate support for themselves. The present study advances research by exploring the variables related to adolescent mental health help-seeking intentions within the school setting. Specifically, this study assesses the utility of the theory of planned behavior in an effort to identify what factors relate to high school students' willingness to seek help at school. A secondary aim of this study was to examine why adolescent boys are consistently less willing to seek help for mental health problems than adolescent girls. Results of this study highlight important factors to target when developing interventions to increase help-seeking intent in high school students.
Smaller-sized fungal fragments (<1μm) may contribute to mold-related health effects. Previous laboratory-based studies have shown that the number concentration of fungal fragments can be up to 500 times higher than that of fungal spores, but this has not yet been confirmed in a field study due to lack of suitable methodology. We have recently developed a field-compatible method for the sampling and analysis of airborne fungal fragments. The new methodology was utilized for characterizing fungal fragment exposures in mold-contaminated homes selected in New Orleans, Louisiana and Southern Ohio. Airborne fungal particles were separated into three distinct size fractions: (i) >2.25μm (spores), (ii) 1.05–2.25μm (mixture), and (iii) <1.0μm (submicrometer-sized fragments). Samples were collected in five homes in summer and winter and analyzed for (1→3)-β-d-glucan. The total (1→3)-β-d-glucan varied from 0.2 to 16.0ngm−3. The ratio of (1→3)-β-d-glucan mass in fragment size fraction to that in spore size fraction (F/S) varied from 0.011 to 2.163. The mass ratio was higher in winter (average=1.017) than in summer (0.227) coinciding with a lower relative humidity in the winter. Assuming a mass-based F/S-ratio=1 and the spore size=3μm, the corresponding number-based F/S-ratio (fragment number/spore number) would be 103 and 106, for the fragment sizes of 0.3 and 0.03μm, respectively. These results indicate that the actual (field) contribution of fungal fragments to the overall exposure may be very high, even much greater than that estimated in our earlier laboratory-based studies.
In this paper, partitioning behaviors of typical neutral (Alanine), acidic (Glutamic acid) and basic (Lysine) amino acids into imidazolium-based ionic liquids [C4mim][PF6], [C6mim][PF6], [C8mim][PF6], [C6mim][BF4] and [C8mim][BF4] as extracting solvents were examined. [C6mim][BF4] showed the best efficiency for partitioning of amino acids. The partition coefficients of amino acids in ionic liquids were found to depend strongly on pH of the aqueous solution, amino acid and ionic liquid chemical structures. Different chemical forms of amino acids in aqueous solutions were pH dependent, so the pH value of the aqueous phase was a determining factor for extraction of amino acids into ionic liquid phase. Both water content of ionic liquids and charge densities of their anionic and cationic parts were important factors for partitioning of cationic and anionic forms of amino acids into ionic liquid phase. Extracted amino acids were back extracted into phosphate buffer solutions adjusted on appropriate pH values. The results showed that ionic liquids could be used as suitable modifiers on the stationary phase of an HPLC column for efficient separation of acidic, basic, and neutral amino acids.
In the context of increasing use of renewable energy sources, residential energy supply systems are changing as well. In this paper, a techno-economical model for the energy supply of a district including both electrical and thermal demand as well as renewable energy generation is developed. Furthermore, a high penetration of fuel cell electric vehicles is assumed and the hydrogen has to be provided by the energy supply system as well. The single components of the energy system are optimal sized, with respect to the total cost of ownership of the system, while the systems operation strategy is defined by a fixed ranking list. A reference case is defined by actual or near future techno-economical assumptions of the components. In the resulting optimal system, the most important components are a large PV system, a SOFC for heat and power generation and a PEM electrolyzer for hydrogen production. The produced hydrogen is used solely to refuel the fuel cell electric vehicles. On this basis, the influences of the components investment costs and the energy purchasing costs on the system configuration are investigated. It is shown that, the PV investment costs as well as the feed-in tariff can cause qualitative differences in the system configuration. Moreover, interactions between all conversion devices with respect to the optimal sizing are identified. Finally, it is shown that if the PV investment costs and the feed-in tariff decreases in the future, a reconversion of the self produced hydrogen in the SOFC becomes economically feasible, even for small natural gas purchasing costs.
In this paper, the catalytic activity of a ferrite/ceria composite ceramic fuel electrode La0.9Ca0.1Fe0.9Nb0.1O3-δ/Sm0.1Ce0.9O2−δ (LCFNb/SDC) for solid oxide reversible cells (SOCs) is studied by using YSZ (Zr0.84Y0.16O2-δ) and LSM/YSZ (LSM(La0.8Sr0.2MnO3-δ)) as electrolyte and oxygen electrode, respectively. The asymmetrical LCFNb/SDC|YSZ|LSM/YSZ cells are prepared and evaluated electrochemically by using DC (cyclic voltammetry (CV) and galvanostatic) and AC impedance techniques in 50% CO: 50% CO2 at the fuel electrode compartment. XRD results indicate LCFNb in the composite fuel electrode is stable in CO and CO2 at high temperature and the LCFNb/SDC membane fuel electrode prepared by infiltration method presents high performance towards CO2 reduction and CO oxidation. The polarization resistance under open circuit in a 50% CO: 50% CO2 gas composition at 800°C is 0.97Ωcm2. However, both the CV and polarized impedance data show that the cell performance is higher for the electrolysis of CO2 than for the oxidation of CO. The polarization resistance in 50% CO: 50% CO2 at 1.4V at 800°C is 0.39Ωcm2. Notably, the cell shows a highly stable activity towards CO2 electrolysis at different applied voltages at the temperature of 800°C.
On the base of an analysis of some literature is shown that a solid state reaction mechanism can have several advantages over a dissolution–precipitation mechanism as the most convenient way to describe the Pb/H2SO4 interface in the PbSO4 region, at least for some of the possible experimental conditions. In support of this view, quantitative analyses of the voltammetric results for the formation and reduction of PbSO4 are presented, showing that it is possible to obtain the kinetic parameters of the reactions occurring at the Pb/PbSO4 interface. From these analyses, it is possible to gain a deeper understanding of how the negative plates of lead acid batteries operate efficiently.
The electrochemical performance of nanocomposites could greatly be improved by rationally designing flexible core-shell heterostructures. Typically, the uniform coating of a thin mesoporous crystalline transition metal oxide shell on flexible graphitized carbon supports can provide both fast ion and electron transport pathways, which is an ideal material for high-performance lithium-ion batteries. Herein, we report a surfactant-templating assembly coating method to deposit an ultrathin mesoporous crystalline TiO2 shell on flexible graphitized carbon supports by using amphiphilic triblock copolymer Pluronic F127 as a template. Taking multi-wall carbon nanotubes (CNTs) as an example support, the obtained flexible CNTs@mTiO2 hybrid mesoporous nanocables exhibit an ultra-high surface area (∼137m2/g), large internal pore volume (∼0.26cm3/g), uniform accessible mesopores (∼6.2nm) and ultrathin highly-crystalline mesoporous anatase shells (∼20nm in thickness). As an anode material for lithium battery, the flexible CNTs@mTiO2 hybrid mesoporous nanocables show high-rate capacity (∼210mAhg−1 at 20C, 1C=170mAg−1), high Coulombic efficiency (nearly 100% during 1000 cycles at 20C) and ultralong-cycling life (keeping ∼210mAhg−1 after 1000 cycles at 20C). The strong synergistic coupling effect between CNT cores and thin mesoporous TiO2 shells, high surface area, accessible large pores and highly crystalline thin mesoporous shells result in excellent performance in lithium batteries. This versatile surfactant-templating assembly coating method can be easily extended to deposit an ultrathin mesoporous TiO2 layer on flat graphene (GR) to form a uniform sandwich-like flexible GR@mTiO2 nanoflakes, which opens up a new opportunity for depositing thin mesoporous transition-metal oxides on graphitized carbon supports for advanced applications in energy conversion and storage, photocatalysis, sensors and drug delivery, etc.
In the search for a nanocomposite which can cycle reversibly as a lithium-ion secondary battery anode while utilizing the electrochemical activity of the matrix material, carbon was chosen as the low weight, low volume expansion phase in a nanocomposite with tin. The nanocomposites were synthesized by pyrolysis of a polymer in the presence of a tin precursor. The samples with the most fine-grained, well distributed tin particles exhibited reversible capacities on the order of 400–500mAh/g. The nanocomposites were analyzed by X-ray diffraction, BET, TEM, and electrochemical cycling.
A reduced graphene oxide (rGO) based film is sandwiched between a sulfur cathode and the separator, acting as a shuttle inhibitor to the sulfur and polysulfides. The lithium–sulfur cell with such a configuration shows an initial discharge capacity of 1260 mAh g−1 and the capacity remains at 895 mAh g−1 after 100 cycles. The excellent electrochemical performance of the cell is attributed to both the functional groups on the rGO sheets that anchor the sulfur and polysulfides and the carbon additive that helps to produce channels for the electrolyte and polysulfide to enter.
Abstract Aphasias are language disorders related to brain disease. Most are related to lesions or disorders of the left hemisphere, since the great majority of right-handed people and over half of left-handed people have left hemisphere dominance for speech. Aphasias are often caused by strokes, though brain injuries, brain tumors, and other pathological disorders such as neurodegenerative diseases and dementia can produce language disorders. The major types of aphasia are Broca's, Wernicke's, global, conduction, anomic, and transcortical aphasias. In addition, syndromes of subcortical aphasia have been described. Alexias and agraphias, acquired disorders of reading and writing, are closely related to aphasia. Aphasia often improves over time, except for those cases resulting from neurodegenerative conditions. Speech and language therapies help to facilitate recovery. Newer, experimental treatments for aphasia are under investigation.
This study investigates an integrated energy system designed to supply 100% heat and power to a remote application, renewably. The system comprises a solar photovoltaic (PV) system with hydrogen-based energy storage (SH), a fuel cell heat recovery arrangement, an electric inline heater (powered by the PVs), and a solar thermal system (ST), altogether operating as a renewable combined heat and power solution. A theoretical simulation model is developed in MATLAB to conduct this study. The addition of the inline heater (powered by the PVs) resulted in improving the overall reliability of this integrated renewable energy arrangement from ∼95% to 100% with no additional costs. Additionally, the system is competitive against diesel generator (for power supply) and gas hot water system that is mostly used conventionally in remote areas.
The influence of Li precursors and calcination atmospheres on the reaction mechanisms, physical properties and electrochemical performance of graphene sheets (GS)-modified nano-Li4Ti5O12 (LTO/GS) has been systematically investigated. Field emission scanning electron microscopy (FE-SEM) and mass spectrometry (MS) results demonstrate the lithium precursor containing carboxyl anion such as lithium acetate (LiAc) and Li2CO3 interact with oxygen groups of graphene oxide (GO) by strong hydrogen bonds to restrict the morphology and the phase formation of products. We also notice from the thermogravimetry (TG) and MS results that the consumption of GS is proportional to oxygen content of lithium precursor. Cyclic voltammetry (CV) and X-ray photoelectric spectroscopy (XPS) results indicate that the product calcined in reducing atmosphere possess smaller electrochemical polarization due to more reduced Ti3+ on the surface of the product. The LTO/GS sample with LiOH as Li precursor calcined in diluted hydrogen atmosphere show the best electrochemical performance with a capacity of 134.4 mAh g−1 at 10C discharge rate and very stable cycling life with a 98.6% capacity retention after 800 cycles at 40C rate. This study not only provides an optimization of Li precursor and calcination condition for LTO/GS anode material, but also guides any future one-step syntheses of lithium composite materials with GO participation.
Lung transplant (LT) aims to extend survival and improve patient-centered outcomes (PCOs) by reducing disability and improving health-related quality of life (HRQL). Few PCO instruments have been validated in LT populations. We aimed to develop and validate a shortened version of the Valued Life Activities (VLA) disability scale specific to LT. We used data from 140 subjects participating in an ongoing cohort study of LT. Subjects completed a survey battery, including VLA items, and physical assessments before LT. To develop a shortened lung transplant specific VLA (LT-VLA), we iteratively deleted items from a longer 32-item VLA battery, retaining the instrumentâ€™s conceptual framework, scoring and performance characteristics. We evaluated LT-VLA validity by testing correlations with a HRQL measure (Short Form-12 Physical Function [SF-12 PF] subscale), FVC% predicted, and 6-minute walk distance (6MWD). Responsiveness was evaluated in 84 subjects who completed assessments before and after LT. The 15-item LT-VLA scoring closely matched the longer VLA (correlations â‰¥0.96) and had excellent internal consistency (Cronbachâ€™s alpha: 0.92). The LT-VLA required only 3 minutes or less to administer compared to 8-9 for the original. The LT-VLA, measured as mean difficulty in performing each of the 15 activities queried, correlated with FVC% predicted (r= -0.30), 6MWD (r= -0.38) and SF-12 PF (r= -0.47) (all p<0.01). The strength and direction of these correlations were as hypothesized, a priori. The LT-VLA mean difficulty was responsive to change from before to after LT: (63% improvement; effect size=1.60). The LT-VLA is a short, easy to administer, valid, and responsive disease-specific PCO instrument that may be useful in clinical and research applications for lung transplantation.
LiNbO3 nanotubes are prepared by biotemplate-assisted synthetic route. The mesoporous LiNbO3 nanotubes can be an ideal platform to immobilize glucose oxidase (GOx) for glucose biosensing. As the GOx-biocatalyzed oxidation of glucose yield H2O2, and LiNbO3 can direct catalyze the generated H2O2. What's more, one dimensional channels will facilitate the diffusion of reactants and ensure adequate contact between glucose and enzymes. Thus the as-prepared biosensor exhibit high sensitivity (52.4μA·mM−1·cm−2), fast response (<2s) and excellent selectivity to glucose. The results suggest the potential implementation of LiNbO3 as a sensing platform for electrochemical detection of biology reagents.
Nanocomposite polymer electrolytes based on a plasticized high molecular weight poly(oxyethylene) (POE) reinforced with high aspect ratio cellulose nanoparticles were reported. The influence of tetra(ethylene) glycol dimethyl ether (TEGDME) as plasticizer is investigated. The study mainly focuses on the dynamic mechanical behavior and ionic conductivity performances. The miscibility of the blend POE/TEGDME was investigated using both thermal and mechanical investigations. Viable polymer electrolytes can be obtained from this combination, conciliating acceptable ionic conductivities and outstanding mechanical performances on a large temperature range.
A solvent-free organocatalyzed process for the transesterification of dimethyl carbonate (DMC) with 1,2-diols under scalable continuous flow conditions is presented. Process parameters, such as temperature, residence time, DMC/glycerol molar ratio and catalyst loading are optimized for the carbonation of bio-based glycerol using 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU) as a model organocatalyst. The catalytic performance of DBU is next compared with other homogeneous organic superbases including the proton sponge, Verkade's base, guanidines and phosphazenes. 2-tert-Butyl-1,1,3,3-tetramethylguanidine (Barton's base) stands as the most efficient organocatalyst, providing glycerol carbonate at 87% selectivity and 94% conversion within 2 minutes of residence time at 1 mol% loading. Representative examples of polystyrene-supported (PS) organic superbases of the amidine, guanidine and phosphazene-types are also considered as alternative heterogeneous catalysts. PS superbases typically enable up to 80 h of continuous operation with minor deactivation at elevated flow rates. The methodology is amenable to a library of other 1,2-diols, including biomass-derived substrates. Depending on the unique structural features of both substrates and products, either on-line IR or on-line NMR analytical procedures are implemented for real-time qualitative reaction monitoring. A final demonstrator showcases the transposition of the glycerol carbonation to a pilot-scale continuous flow reactor, affording the target cyclic carbonate with a 68.3 mol per day productivity (∼8 kg per day).