batterydata/paper-abstracts huggingface dataset:
With an aim to improve the 5V capacity and cyclability of the LiMn1.5Ni0.5O4 spinel oxide, three series of Cr substitutions have been pursued with y ≤0.2: LiMn1.5Ni0.5−y Cr y O4, LiMn1.5−0.5y Ni0.5−0.5y Cr y O4, and LiMn1.5−0.33y Li0.33y Ni0.5−y Cr y O4. While the first series involves an increase in the Mn3+ content, the second and third series are designed to maintain charge neutrality (Mn4+, Ni2+, Cr3+, and Li+) without introducing Mn3+ ions. The LiMn1.5Ni0.5−y Cr y O4 series experiences a widening of the 4V plateau and a decrease in the 5V capacity compared to LiMn1.5Ni0.5O4 due to an increase in the Mn3+ content. On the other hand, the LiMn1.5−0.5y Ni0.5−0.5y Cr y O4 series shows a suppression of the 4V plateau and an increase in the 5V capacity due to the elimination of the Mn3+ions. The LiMn1.5−0.33y Li0.33y Ni0.5−y Cr y O4 series shows a suppression of the 4V plateau at low Cr contents, but an increase in the 4V plateau as the Cr content increases above 0.1. Among the various compositions investigated, LiMn1.45Ni0.45Cr0.1O4 exhibits the best combination of high 5V capacity (128mAh/g at 5–4.2V) and excellent capacity retention (98% in 50 cycles) compared to 118mAh/g and 92% for LiMn1.5Ni0.5O4.
Functional porous carbon (PC) derived from bio-friendly shaddock peel has been firstly explored as catalyst for vanadium redox flow battery (VRB). The prepared PC is micro-mesoporous with high BET surface area of 882.7 m2 g−1, has some surface oxygen-containing functional groups, and is doped with N and P heteroatoms. These three factors greatly favor the electrochemical reactions of VO2+/ VO 2 + on the PC modified glass carbon (PC-GC). Compared with the naked GC and graphite modified GC, the PC-GC presents a lower peak separation (66 mV), higher anodic current density (17.1 mA cm−2) and cathodic current density (15.0 mA cm−2). The VRB using PC modified graphite felt (GF) as positive electrode demonstrates an enhanced voltage efficiency of 82.7% at the current density of 60 mA cm−2, and a better rate performance than that from the virginal GF.
A method is presented by which a simple physical model of radiative transfer may be used to estimate the vertical distribution of the plant area index (PAI) from measurements of average photosynthetically active radiation at various heights within the canopy and a known phytoelement inclination distribution. Eight semi-natural mountain grasslands, differing in land use, are investigated. Using a set of baseline parameters obtained from the literature, predicted plant area indices compare both qualitatively and quantitatively favourably with those determined from destructive harvesting. Model predictions are shown to be sensitive to the phytoelement dispersion coefficient and phytoelement optical properties. Due to mutually opposing effects on PAI predictions, their parameterisation is found to be critical. Predictions assuming a spherical phytoelement angle distribution are demonstrated to be not significantly different from those based on measured inclination distributions.
The potential of hybrid wind/solar energy system in the west coast area of Saudi Arabia is analyzed in this paper. The investigation puts emphasis on the energy production and cost of energy from both wind turbine and photovoltaic (PV) in the hybrid system. Unmet electric load and excess electricity are taken into consideration. The annual average solar irradiation and wind speed considered in this study are 5.95 kWh/m2/day and 3.53 m/s, respectively. MATLAB and HOMER software are used to perform the technical and economic analyses of the hybrid system. As indicated from the simulation results, the PV array shares more electricity production than the wind turbine generator if both wind turbine and PV array are utilized in the wind/solar hybrid system with the same sizes. The wind levelized cost of energy is $0.149/kWh, which is more expensive than the solar energy of $0.0637/kWh. The energy cost of the hybrid system is dominated by battery and wind turbine expenses.
The thermal behavior of pouch-type lithium-ion batteries during discharge and charge cycles is investigated by numerical simulation. A transient thermal model using finite element method software is developed through the modification of an electrochemical-thermal model. The developed model is validated with experimental data. For the experiment, a 304252 pouch cell is fabricated and tested in the laboratory. This model captures the dynamic responses of temperature, and distributions of current density and temperature, during discharge and charge cycles. Our results indicate that the discharge temperature is higher than the charge temperature at cut-off voltage. The temperature distribution upon discharge is similar to that of charge. On the other hand, different temperature distributions are observed at various C rates. The temperature profiles obtained from modeling and experiment are in good agreement.
Organophosphate compounds, which induce organophosphate poisoning, were originally used as pesticides. But this type of product has also been used as warfare nerve agent like sarin, soman, Russian VX, or tabun. HI-6-dimethanesulfonate is a salt of the oxime HI-6 used in the treatment of nerve-agent poisoning. It is known to be the best re-activator component of inactivated acetyl cholinesterase. HI-6-dimethanesulfonate has shown a higher level of solubility with similar potency to reactivate acetyl cholinesterase and a similar pharmacokinetics profile compared with HI-6 dichloride. HI-6 dimethanesulfonate was tested for its mutagenic and genotoxic potential by use of the standard ICH S2R (1) battery for the evaluation of pharmaceuticals. HI-6-dimethanesulfonate was mutagenic in the Ames test only in the presence of metabolic activation. In the mutation assay at the Tk locus in L5178Y mouse-lymphoma cells, HI-6-dimethanesulfonate showed mutagenic activity both with and without metabolic activation, with a significant increase in small colonies. The effects were in favour of a clastogenic activity. It was concluded that the compound was mutagenic and possibly clastogenic in vitro. In contrast, the in vivo micronucleus test in rat bone-marrow did not demonstrate any genotoxic activity and the Comet assay performed in rat liver did not show any statistically or biologically significant increases in DNA strand-breaks. The results of both in vivo studies performed on two different organs with two endpoints are sufficient to conclude the absence of a genotoxic hazard in vivo and to consider that there is no genotoxic concern in humans for HI-6-dimethanesulfonate.
P2-type Na2/3[Ni1/3Mn2/3]O2 cathode material has been synthesized via spray drying method and a two step solid state process. Electrochemical behavior of the prepared material as cathode material for sodium ion battery was investigated in different charge-discharge voltage ranges. The results indicated that the cycling performance of the P2-Na2/3[Ni1/3Mn2/3]O2 cathode greatly depended on the voltage window. The material showed excellent reversibility between 2.0V and 4.0V with reversible capacity of 86mAhg−1 (0.1C) and 77mAhg−1 (1C). XRD analyses indicated that crystal structure of the P2-type Na2/3[Ni1/3Mn2/3]O2 could be well maintained after long term cycling in 2.0–4.0V. When the upper limiting voltage was increased to 4.5V, the crystal structure of P2-Na2/3[Ni1/3Mn2/3]O2 was irreversibly damaged due to over extraction of Na+ in 4.0–4.5V. On the other hand, when the cycling voltage range was between 1.6V and 3.8V, the discharge capacities increased to 135 mAh g−1 (0.1C) and 108mAhg−1 (1C), respectively. However, the cycling stability in 1.6–3.8V was not as excellent as that in 2.0–4.0V. This maybe due to the lattice stress caused by the over insertion of Na+ in the structure at lower voltage.
Polyethylene glycol (PEG, mean molecular weight of 10,000) has been used to prepare a Li3V2(PO4)3/C cathode material by a simple solid-state reaction. The Raman spectra shows that the coating carbon has a good structure with a low I D/I G ratio. The images of SEM and TEM show that the carbon is dispersed between the Li3V2(PO4)3 particles, which improves the electrical contact between the corresponding particles. The electronic conductivity of Li3V2(PO4)3/C composite is 7.0×10−1 S/cm, increased by seven orders of magnitude compared with the pristine Li3V2(PO4)3 (2.3×10−8 S/cm). At a low discharge rate of 0.28C, the sample presents a high discharge capacity of 131.2mAh/g, almost achieving the theoretical capacity (132mAh/g) for the reversible cycling of two lithium. After 500 cycles, the discharge capacity is 123.9mAh/g with only 5.6% fading of the initial specific capacity. The Li3V2(PO4)3/C material also exhibits an excellent rate capability with high discharge capacities of 115.2mAh/g at 1C and 106.4mAh/g at 5C.
The short-acting beta-2 adrenoceptor agonists (β2-agonists), such as salbutamol, are effective bronchodilators used to treat asthma. They lack significant anti-inflammatory effect in vivo as well as on isolated alveolar macrophages even though they exhibit this effect on freshly isolated monocytes. The purpose of this study was to determine if this observation is related to a change in the expression and/or function of surface β2-receptors during the differentiation of these cells to macrophages. Purified monocytes, cultured for 1–48h were pre-treated with the β2-agonists (salbutamol or procaterol) or PGE2 before being stimulated with bacterial lipopolysaccharide (LPS). Subsequently, the amount of TNF-α (a typical inflammatory mediator) released over 24h, as well as agonist-stimulated cAMP, were determined by enzyme immunoassays. Western blotting techniques were used to study the expression of the membrane β2-receptor protein. Results showed that in freshly isolated human monocytes, both the β2-agonists and PGE2 significantly inhibited LPS-induced TNF-α release as well as increased intracellular cAMP. After culturing adherent monocytes for 24–48h, the ability of the β2-agonists to produce both effects was completely lost, whereas that of PGE2 was essentially intact. Western blotting data showed a near complete loss of surface expression of β2-receptors in cells cultured for ≥24h. These results show that as human monocytes adhere to surfaces to begin differentiation into macrophages, they selectively lose their surface β2-receptors and hence become insensitive to the anti-inflammatory effect of β2-agonists. This may explain why β2-agonists lack significant anti-inflammatory effect on alveolar macrophages or in clinical asthma.
The search for next-generation solid-state superionic conductors has attracted significant attention. Among Na superionic conductors, Na11Sn2PS12 has been reported to have a room temperature ionic conductivity of 1.4 mS/cm. In this study, we employ density functional theory to study the stability of Na11Sn2PS12 and further explore the substitution of Sn with Ge. Our results indicate that Na11Ge2PS12 is more stable than Na11Sn2PS12. Furthermore, substituting Sn with Ge increases the band gap, improves the room temperature ionic conductivity by a factor of 2, and lowers the activation energy of Na hopping. Statistical analysis suggests that Na11Ge2PS12 has a faster diffusion along the ab-plane compared to the c-axis. The Na diffusion in Na11Ge2PS12 appears to occur with two different mechanisms depending on temperature: 1) an ion hopping process at lower temperatures (<800 K); 2) a fluid-like distribution of Na ions at higher temperatures (>1000 K). The computations suggest that Na11Ge2PS12 is a promising candidate as a solid Na electrolyte due to its high room temperature ionic conductivity and phase stability. In light of these simulation results, we expect to stimulate further experimental studies on Na11Ge2PS12.
Modifications of the local structure and lattice parameters in LiFe1−x Ni x PO4 (0 < x < 0.15,0.9,1.0) olivine-type solid solutions have been studied by X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Samples have been synthesized and characterized in our laboratory, and a preliminary electrochemical characterization shows that Ni doping increases slightly the performances in Li-ion cells at low Ni concentrations x. Results of both XRD and XAS techniques are consistent and indicate ordering of Li in the M1 site, and of Fe and Ni in the M2 site of the olivine structure. Ni doping is found to induce an anisotropic shrinking of the unit cell with both Fe and Ni six-coordinated with oxygens, occupying distorted octahedral sites. The local structure measured by XAS shows that average Fe–O and Ni–O distances do not change appreciably with Ni doping indicating that the reduction of cell size is mainly associated with the presence of shorter Ni–O distances at M2 sites. Possible connections among the presence of a distribution of distorted octahedra of different size in the structure and different electrochemical performances of the material as a function of doping are briefly discussed.
Accurate battery State of Charge (SOC) estimation is of great significance for safe and efficient energy utilization for electric vehicles. This paper presents a comparison between a novel robust extended Kalman filter (REKF) and a standard extended Kalman filter (EKF) for Li-ion battery SOC indication. The REKF-based method is formulated to explicitly compensate for the battery modeling uncertainty and linearization error often involved in EKF, as well as to provide robustness against the battery system noise to some extent. Evaluation results indicate that both filters have a good average performance, given appropriate noise covariances, owing to a small average modeling error. However, in contrast, the REKF-based SOC estimation method possesses slightly smaller root-mean-square (RMS) error. In the worst case, the robustness characteristics of the REKF result in an obviously smaller error bound (around by 1%). Additionally, the REKF-based approach shows superior robustness against the noise statistics, leading to a better tolerance to inappropriate tuning of the process and measurement noise covariances.
This paper examines the behaviour of lithium polymer electrolytes based on aromatic sulfonamide salts tailored to optimize negative charge delocalization through the aromatic ring and up to the nitro substituents located in the para and para/ortho positions of the nitrogen of the sulfonamide anion. For the first time, lithium salt dissociation has been connected to the Σ + value. Thanks to the tailoring of these anions and to this physico-chemical approach it has been possible to show that resonance electron-withdrawing effects, as opposed to inductive ones, are decisive in reaching high conductivities in aprotic polymer electrolytes. Moreover the dissociation enhancement that can be expected, using the Σ + value of NO2, from the introduction of an additional nitro group, is in good agreement with the conductivity enhancement.
Requirements analysis defines the goals and evaluation criteria of system design. We introduce a methodology for requirements analysis for customization based on large sample interactive testing, with the premise that analysis of user behaviour with prototypes leads to requirements discoveries. The methodology uses a relatively large sample (1) to identify relevant user subgroups, (2) to observe significant empirically determined group differences in the context of task and tool use and (3) to estimate the groups’ different requirements and derive design implications. Between 20 and 50 participants are used per test, rather than the three to five often recommended for user testing. Statistical relationships are investigated between subgroups in terms of background variables, questionnaire items, performance data, and coded verbal statements. Customization requirements are inferred from the significant differences observed between empirically determined groups. The methodological framework is illustrated in a case study involving the use of clinical resources on handheld devices by three groups of physicians. The groups were found to have different needs and preferences for evidence-based resources and device form factor, implying opportunities and necessities for group customization requirements. Relevance to industry In safety-critical domains such as health care, it is essential to assess user needs and preferences regarding devices and systems to inform appropriate customizations. We present a methodological framework and case study that demonstrates how large sample user testing can supplement typical methods of requirements analysis to provide contextualized, quantitative accounts of group differences and customization requirements.
Several organic amines with –NH2 functional groups and inorganic ammoniums with –NH4 + functional groups have been comparatively investigated as stabilizers of the V(V) electrolyte for vanadium redox flow battery (VRB) to improve its stability and electrochemical performance. Thermal stability tests showed that chitosan (CTS) and nonionic-type polyacrylamide (NPAM) additives with –NH2; ammonium thiocyanate (ATC), ferrous ammonium sulfate (FAS) and ammonium ferric sulfate (AFS) additives with –NH4 + could significantly improve the thermal stability of the V(V) electrolyte over a wide temperature range of −5°C to 45°C. The electrochemical behavior of the V(V) electrolyte with these preferred additives was further studied by cyclic voltammetry (CV), steady state polarization, electrochemical impedance spectroscopy (EIS) and charge–discharge test. The results indicated that the electrochemical activity and reversibility for the V(V) electrolyte with the best additive CTS with –NH4 + was significantly improved compared with the additives with –NH2 and pristine one. In addition, the VRB employing the positive electrolyte with CTS exhibited excellent cycling stability and charge–discharge behavior with a high energy efficiency of 82.5%. The N-containing and O-containing functional groups of CTS in the V(V) electrolyte could modify the electrode and further improve the electrochemical performance and cycling stability of VRB.
1M solution of lithium bis(oxalato)borate (LiBOB) in ethylene carbonate (EC) and dimethyl carbonate (DMC) mixture (1:1 volume ratio) was studied as an electrolyte for supercapacitors with high surface area micromesoporous carbide-derived carbon electrodes, synthesized from Mo2C. Electrochemical characteristics were studied using cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and constant current charge/discharge methods. The established region of ideal polarizability for a two-electrode system was ∼3.0V and the limiting capacitance, calculated from EIS data, was 125Fg−1. Three-electrode measurements showed that solid electrolyte interface formation is a very complex process and partially blocks the adsorption and intercalation/deintercalation processes on the negatively charged electrode. The capacitance of a supercapacitor cell decreased by 33% during 5000 galvanic cycles between applied cell voltages from 1.5V to 3.0V. Calculated maximal energy and power densities were 42.5Whkg−1 and 67.3kWkg−1, respectively. Thus, the tested LiBOB electrolyte is a potential candidate for long-lasting supercapacitors with high power density.
Cloud computing offers sufficient computing and storage resources that can be used to provide multimedia services. Migrating the existing multimedia service to cloud brings a new challenging issue, i.e., remote display of video contents. To reduce the bandwidth consumption especially for mobile users, it is desired to encode video before sending to client. Existing encoding methods have unique advantages and disadvantages, differing their performance under varying situations. Thus, we propose to use multi-encoder method to solve the real-time remote display problem for remote multimedia cloud. To select the most appropriate encoder, factors including cost, application requirement, network, client device and codec implementation are considered. In this paper, we form a non-linear programming model, and provide an example to illustrate how to apply the proposed model for getting desired optimization.
Nafion, within the anode and cathode catalyst layers, plays a large role in the performance of fuel cells, especially during the operation of the direct formic acid fuel cell (DFAFC). Nafion affects the proton transfer in the catalyst layers of the fuel cell, and studies presented here show the effects of three different Nafion loadings, 10wt.%, 30wt.% and 50wt.%. Short term voltage–current measurements using the three different loadings show that 30wt.% Nafion loading in the anode shows the best performance in the miniature, passive DFAFC. Nafion also serves as a binder to help hold the catalyst nanoparticles onto the proton exchange membrane (PEM). The DFAFC anode temporarily needs to be regenerated by raising the anode potential to around 0.8V vs. RHE to oxidize CO bound to the surface, but the Pourbaix diagram predicts that Pd will corrode at these potentials. We found that an anode loading of 30wt.% Nafion showed the best stability, of the three Nafion loadings chosen, for reducing the amount of loss of electrochemically active area due to high regeneration potentials. Only 58% of the area was lost after 600 potential cycles in formic acid compared to 96 and 99% for 10wt.% and 50wt.% loadings, respectively. Lastly we present cyclic voltammetry data that suggest that the Nafion adds to the production of CO during oxidation of formic acid for 12h at 0.3V vs. RHE. The resulting data showed that an increase in CO coverage was observed with increasing Nafion content in the anode catalyst layer.
As a part of the longitudinal Chronic Obstructive Pulmonary Disease (COPD) study, Subpopulations and Intermediate Outcome Measures in COPD study (SPIROMICS), blood samples are being collected from 3200 subjects with the goal of identifying blood biomarkers for sub-phenotyping patients and predicting disease progression. To determine the most reliable sample type for measuring specific blood analytes in the cohort, a pilot study was performed from a subset of 24 subjects comparing serum, Ethylenediaminetetraacetic acid (EDTA) plasma, and EDTA plasma with proteinase inhibitors (P100™).
The short circuit of lithium-ion batteries induced by mechanical abuse is a great concern in electric vehicle design. It remains a challenge to fully understand the nature of the mechanical damage process with the aim of improving battery crash safety. The present paper investigates the evolution of the damage process for a lithium-ion pouch cell under indentation by loading the cell to various force levels. A significant inflection point on the force-indentation curve is observed before the force peak. Post-mortem examinations indicate that the characteristic change in the local slope of the curve is related to the change occurring at the local interfaces, including three phenomena - formation of tight adhesion on the anode-separator interfaces, delamination in the separators and decoating of graphite particles from the anodes. Analysis of the fracture sequence at the onset of short circuit clearly shows that the number of short-circuited electrode pairs is equal to the number of anode layers adhered with delaminated separator material before fracture occurs. The experimental study in the present paper implies that the inflection point on the force-indentation curve may be an indicator of damage initiation inside pouch cells under indentation.