batterydata/paper-abstracts huggingface dataset:
The hierarchical porous nanoarchitecture of WSe2/reduced graphene oxide (WSe2/RGO) hybrid, constructed by few-layered WSe2 nanosheets in-situ grown on RGO nanosheets, has been synthesized through a facile one-pot solvothermal method. The WSe2/RGO hybrid can be used as an efficient anode for lithium-ion (Li-ion) batteries and exhibits much better electrochemical performance than that of bare WSe2: the WSe2/RGO hybrid delivers a high initial discharge capacity of 744 mA h g−1 at 0.2C and it remains 528 mA h g−1 after 80 cycles, while the bare WSe2 has a lower discharge capacity of 549 mA h g−1 at 0.2C and it remains only 98 mA h g−1 after 80 cycles; the WSe2/RGO hybrid also demonstrates remarkably rate capability under different current rates from 0.2 to 8C. Those outstanding electrochemical performances of WSe2/RGO hybrid can be assigned to its unique nanoarchitecture: the RGO nanosheets with high conductivity work as the skeleton of WSe2/RGO anode facilitating the electron transfer; the RGO nanosheets can effectively prevent WSe2 from the aggregation and promote the in-situ growth of WSe2 layers on graphene, guaranteeing the formation of hierarchical porous nanoarchitecture with abundant electrochemically active sites, which can allow for efficient ionic diffusion and easy electrolyte infiltration. This study presents a rational-designed structure and facile strategy to fabricate transition metal dichalcogenides (TMDs)/graphene hybrid as promising anodes for lithium-ion batteries.
This paper describes a remote monitoring system that can be set up in an operating center to monitor the state of valve regulated lead acid batteries (VRLA) used as a backup power supply for telecommunications. This system has a battery voltage monitoring function, a lifetime prediction function based on ambient temperature, and a discharge circuit diagnosis function. In addition, the system can be equipped with an internal resistance measurement function and an electrolyte leakage detection function to further insure power-supply reliability. Various states of batteries observed with the system are transmitted to the remote operating center by a remote monitoring function. This function enables obtaining immediate information about the condition of batteries and helps to avoid unexpected failures.
Two pilot-scale submerged-bed microbial biofilms were set up for the removal of Cr(III) and Pb(II) from groundwater, and the biological activities and structure of the bacterial communities developed in the presence of the heavy metals were analyzed. Artesian groundwater was polluted with Cr(III) or Pb(II) (15 mg/l) and amended with sucrose (250 mg/l) as carbon source. While Pb(II) was over 99% removed from groundwater during long-term operation (130 days), the efficiency of the removal of Cr(III) significantly decreased in time (95–73% after 60 days). Cr(III)-amended biofilms displayed significant lower sucrose consumption, ATP cell contents and alkaline phosphatase activity, compared to biofilms formed in the presence of Pb(II), while analysis of exopolymers demonstrated significant differences in their composition (content of carbohydrates and acetyl groups) in response to each heavy metal. According to transmission electron microscopy (TEM) and electron-dispersive X-ray analysis (EDX), Cr(III) bioaccumulated in the exopolymeric matrix without entering bacterial cells, while Pb(II) was detected both extra and intracellularly, associated to P and Si. Temperature-gradient gel electrophoresis (TGGE) profiling based on partial amplification of 16S rRNA genes was used to analyze the differences in the structure of the biofilm bacterial communities developed under exposure to each heavy metal. Prevalent populations in the biofilms were further identified by reamplification and sequencing of isolated TGGE bands. 75% of the sequences in the Pb(II) biofilter were evolutively close to the Rhodobacterales, while in the Cr(III) biofilter 43% of the sequences were found affiliated to the Rhizobiales and Sphingomonadales, and 57% to Betaproteobacteria.
Aim To design and perform a face and content validation of a questionnaire to measure the competence of hospital RN to report medication incidents. Methods Content and face questionnaire validation descriptive study. A review of the literature was performed for the creation of items. A panel of six experts assessed the relevance of the inclusion of each item in the questionnaire by calculating the position index; items with position index >0.70 were selected. The questionnaire was piloted by 59 RN. Finally, a meeting was convened with experts, in order to reduce the length of the piloted questionnaire through review, discussion and decision by consensus on each item. Results From the literature review, a battery of 151 items grouped into three elements of competence: attitudes, knowledge and skills was created. 52.9% (n=80) of the items received a position index >0.70. The response rate in the pilot study was 40.65%. The median time to complete the questionnaire was 23:35min. After reduction by the experts, the final questionnaire comprised 45 items grouped into 32 questions. Conclusions The NORMA questionnaire, designed to explore the competence of hospital RN to report medication incidents, has adequate face and content validity and is easy to administer, enabling its institutional implementation.
DuPont Separations Solutions of Wilmington, Delaware, USA, says that its recently developed Hybrid Membrane Technology (HMT) will allow pillow and mattress covers to deliver unsurpassed protection from a range of harmful allergens, without sacrificing personal comfort.
Fe2O3 wrapped by few layered graphene nanosheets composites (Fe2O3-FLG) have been synthesized via a facile and massive one-step P-milling method, which is effective in reducing the particle size of Fe2O3 and exfoliating the graphite into FLG. The composite shows good electrochemical performance due to the tight wrapping of FLG nanosheets, which is beneficial to electric conductivity and integrity of the electrode. The sample treated under 20 h retains a reversible capacity of 758 mAh g−1 at 200 mA g−1 after 300 cycles, which equals to 88% of its theoretic capacity. With the superior electrochemical performance, Fe2O3-FLG composites prepared via the P-milling method could be promising as anode materials for high performance lithium-ion batteries.
We recently proposed Li-rich vanadium monodiphosphate Li9V3(P2O7)3(PO4)2 as a novel polyanion-type cathode for rechargeable Li batteries. Herein, the Li9V3−x Al x (P2O7)3(PO4)2 solid solutions are obtained in different ratios of V and Al via solid-state reaction at 750°C in high-purity N2. The cell parameters (including a, c and V) of Li9V3−x Al x (P2O7)3(PO4)2 decrease in a linear way with Al-doping content. The intrinsic electronic conductivity of Al-doped samples reaches ∼10−7 Scm−1, which is more than one order of magnitude higher than that of the undoped one. The electrochemical insertion/extraction properties of the trigonal Li9V3−x Al x (P2O7)3(PO4)2 (x =0.00, 0.10, 0.25, and 0.50) phases are also presented. The Al-doped phases are demonstrated the better capacity retention and higher output voltage than that of the pristine one. After 30 cycles, Li9V2.75Al0.25(P2O7)3(PO4)2 can keep 92.4%, 87.7%, and 85.5% of the initial capacity under the current rates of 0.2C, 0.5C and 1.0C, respectively. The favorable voltage polarization, enhanced electronic conductivity, and dramatically contractible particle size after Al doping play significant contributions of comparatively good electrochemical performance of Li9V2.75Al0.25(P2O7)3(PO4)2 sample.
Crystallization of a precursor Li10GeP2S12 (LGPS) glass electrolyte by heat treatment significantly improves its ionic conductivity. The LGPS crystalline phase obtained by heat treatment above 450 °C shows an ionic conductivity on the order of 10−2 S/cm. To clarify the correlation between the crystallization behavior of precursor LGPS glasses and ionic conductivity, we developed an observation technique to visualize precipitated nanocrystallites and a new method to evaluate the crystallization degree via transmission electron microscopy (TEM). In-situ TEM observation revealed that LGPS nanocrystallites precipitated above 450 °C and their size remained fundamentally intact during heating. That is, the crystallization behavior could be characterized by only the formation of LGPS nanocrystallites in an amorphous matrix. In addition, the crystallization degree was quantitatively evaluated from electron diffraction patterns. The crystallization degree remarkably increased at around 450 °C and reached more than 60% above 450 °C. Based on these results, a high ionic conductivity of approximately 1.0 × 10−2 S/cm was confirmed to be directly associated with the appearance of the LGPS crystalline phase.
Lithium titanium oxide (Li4Ti5O12) is a promising anode material, owing to its superior safety and reliability. However, the main challenge of Li4Ti5O12 is the low material conductivity which restricts its electrochemical performance. In order to use Li4Ti5O12 in practical sodium-ion batteries, copper-doped Li4Ti5O12 (Li4−x Cu x Ti5O12, x = 0, 0.05, 0.1) nanoparticles were prepared to enhance the electronic conductivity. Copper-doped Li4Ti5O12 nanoparticles were then embedded in continuous carbon nanofibers (CNFs), which gave rise to fast electron transfer along the fiber direction. After copper-doping and CNF embedding, the resultant copper-doped Li4Ti5O12/CNFs achieved excellent reversible capacity (158.1 mAh g−1) at 30 mA g−1, high coulombic efficiency (99.87%), and good capacity retention (91%) after 150 cycles. In addition, copper-doped Li4Ti5O12/CNFs also exhibited good rate capability. It is, therefore, demonstrated that copper-doped Li4Ti5O12/CNFs are promising anode candidate.
The intermediate phase of NiS2 is thought to be a bottleneck currently to improve the overall performance of Li/NiS2 thermal batteries because of its low conductivity and close formation enthalpy between NiS2 and the intermediate phase (NiS, Ni3S2, etc). For improving the discharge performances of Li/NiS2 thermal batteries, the nano NiS2 with an average size of 85 ± 5 nm is designated as a cathode material. The electrochemical measurements show that the specific capacity of nano NiS2 cathode is higher than micro NiS2. The nano NiS2 cathode exhibits excellent electrochemical performances with high specific capacities of 794 and 654 mAh g−1 at current density of 0.1 and 0.5 A cm−2 under a cut-off voltage of 0.5 V, respectively. These results show that the rapid intermediate phase evolution from the nanocrystallization can obviously enhance use efficiency of NiS2 and improve discharge performances of thermal batteries.
Cognitive impairment, anxiety- and depressive-like symptoms are well recognized outcome of cerebral ischemia in clinical and preclinical settings. Rolipram, a phosphodiesterase-4 (PDE-4) inhibitor, improves cognition and produces anxiolytic- and antidepressant-like effects in rodents. Rolipram also exerts anti-inflammatory effects and enhances survival of newborn hippocampal neurons in mice subjected to transient global cerebral ischemia. Here, we evaluated the effects of chronic rolipram treatment in mice subjected to transient global brain ischemia. C56B6/7 mice were subjected to bilateral common carotid artery occlusion (BCCAO) and were then tested in a multi-tiered behavioral battery including the elevated zero maze (EZM), open field (OF), object location test (OLT), and forced swim test (FST). We also investigated the effects of rolipram on hippocampal neurodegeneration and the expression of the neuronal plasticity markers doublecortin (DCX) and microtubule-associated protein (MAP-2). Ischemic mice exhibited memory deficits OLT, higher levels of anxiety EZM and behavioral despair FST. BCCAO caused neuronal loss in the CA3 hippocampal subfield and basolateral amygdala (BLA). In the hippocampus of BCCAO mice, a disrupted neuronal plasticity was evidenced by decreased DCX expression. Chronic treatment with rolipram attenuated the behavioral effects of BCCAO. Rolipram also decreased neurodegeneration in the CA3 while it increased dendritic arborization of DCX-immunoreactive (DCX-IR) neurons and microtubule associate MAP-2 expression in the hippocampus of BCCAO mice. These data suggest that chronic inhibition of PDE-4 can be a useful therapeutic strategy to improve the emotional and cognitive outcomes of transient global cerebral ischemia.
The performance of vanadium flow batteries (VFBs) is closely related to the materials used in the bipolar plates. Carbon-based composite bipolar plates are particularly suitable for VFB applications. However, most original preparation methods cannot simultaneously achieve good electrical conductivity and mechanical performance. In this paper, we propose a novel approach to fabricating bipolar plates with carbon plastic materials, including four steps, namely coating a poly (vinylidene fluoride) (PVDF) solution onto carbon felt, solvent evaporation, hot-pressing, and surface modification. The resulting bipolar plates showed high conductivity, good mechanical strength, and corrosion resistance. Surface modification by coating with carbon nanotubes (CNTs) removed the PVDF-rich layer from the surface of the carbon fibers. The high surface area of the CNT withdrew PVDF resin from the carbon fiber surface, and promoted the formation of a conductive network. The flexibility and battery charge-discharge cycle measurements showed that the composite bipolar plates can meet requirements for VFB applications.
The recently reported fast oxygen reduction kinetics at the interface of (La,Sr)CoO3−δ (LSC113) and (La,Sr)2CoO4+δ (LSC214) phases opened up new questions for the potential role of dissimilar interfaces in advanced cathodes for solid oxide fuel cells (SOFCs). Using first-principles based calculations in the framework of density functional theory, we quantitatively probed the possible mechanisms that govern the oxygen reduction activity enhancement at this hetero-interface as a model system. Our findings show that both the strongly anisotropic oxygen incorporation kinetics on the LSC214 and the lattice strain in the vicinity of the interface are important contributors to such enhancement. The LSC214(100) surface exposed to the ambient at the LSC113/LSC214 interface facilitates oxygen incorporation because the oxygen molecules very favorably adsorb onto it compared to the LSC214(001) and LSC113(001) surfaces, providing a large source term for oxygen incorporation. Lattice strain field present near the hetero-interface accelerates oxygen incorporation kinetics especially on the LSC113(001) surface. At 500 °C, 4 × 102 times faster oxygen incorporation kinetics are predicted in the vicinity of the LSC113/LSC214 hetero-interface with 50% Sr-doped LSC214 compared to that on the single phase LSC113(001) surface. Contributions from both the anisotropy and the local strain effects are of comparable magnitude. The insights obtained in this work suggest that hetero-structures, which have a large area of (100) surfaces and smaller thickness in the [001] direction of the Ruddlesden–Popper phases, and larger tensile strain near the interface would be promising for high-performance cathodes.
All-solid-state batteries have been desired for the purpose of safety improvement of lithium secondary batteries. In order to improve performance of all-solid-state cells, the formation technique of a favorable interface between active materials and solid electrolytes should be developed. The nanocomposite of the NiS active material and the 80Li2S·20P2S5 (mol%) electrolyte was synthesized via a mechanochemical reaction and applied as an electrode to all-solid-state lithium secondary cells. The capacity of the cell with the nanocomposite electrode was larger than that with an electrode prepared by hand-mixing of the active material and the electrolyte powder at both current densities of 64μAcm−2 and 1.28mAcm−2. The cell with the nanocomposite showed 360mAhg−1 after 50 cycles at 1.28mAcm−2 in the potential range from 1.0 to 4.0V vs. Li.
3D ultra-thin carbon networks are ideal skeleton structures for loading active materials as energy storage and conversion devices. In this work, excellent cathode materials for sodium ion batteries were successfully prepared by homogeneously anchoring NaxKyMnFe(CN)6 (x + y ≤ 2, NaK-MnHCF) on hierarchical porous 3D N-doped ultra-thin carbon networks (3DNC). The compounds present a high reversible capacity, good rate performance, and superior cycling stability. Combined fully experimental analysis and first-principles calculation, the interfacial synergistic effect between 3DNC and NaK-MnHCF on the sodium storage capacity is revealed, contributing to the extra capacity and electrical conductivity. Furthermore, considerable content of capacitive-controlled sodium storage of NaK-MnHCF@3DNC conduces to the rate performance. These results reveal an efficient route for the fabrication of other cathode materials for sodium ion batteries as high-performance energy storage devices.
Exposure to electronic-cigarette (e-cig) aerosols induces potentially fatal e-cig or vaping-associated lung injury (EVALI). The cellular and molecular mechanisms underlying these effects, however, are unknown. We used an air–liquid interface (ALI) in vitro model to determine the influence of two design characteristics of third-generation tank-style e-cig devices—resistance and voltage—on (1) e-cig aerosol composition and (2) cellular toxicity.
Ni-rich ternary cathode materials have attracted great attention because of its high energy density, good cycle performance and high rate performance. However, it suffers from the poor electrochemical performance at elevated temperature and high cut-off voltage due to intrinsic grievous side effects. Herein, a core-shell structure of LiNi0.6Co0.2Mn0.2O2 as the core and Li1.2Ni0.2Mn0.6O2 as the shell which integrated the structural stability of Ni-rich materials and the surface chemical stability of Li-rich materials was purposefully designed via a polyvinyl pyrrolidone (PVP)-assisted sol-gel method and a novel chemical activation for the Li-rich shell with AlF3 treatment. Research by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy methods (TEM), and energy dispersive X-ray spectrometer (EDS) have been proved that the surface of the host materials was deposited with a uniform shell layer of Li1.2Ni0.2Mn0.6O2 and AlF3 particles. As a result, the core-shell materials displayed excellent cycle performance: 94.0% capacity retention after 100 cycles (2.0–4.5 V under 1C and 25 °C) especially at high temperature≈50 °C: 86.5% capacity retention.
A novel approach in modeling the ionic transport in the electrolyte of Li-ion batteries is here presented. Diffusion and migration processes govern the transport of ions in solution in the absence of convection. In the porous electrode theory [1] it is common to model these processes via mass balance equations and electroneutrality. A parabolic set of equations arises, in terms of a non constant electric field which is afflicted by the paradox of being generated without electrical charges. To remedy this contradiction, Maxwell's equations have been used here, coupled to Faraday's law of electrochemical charge transfer. The set of continuity equations for mass and Maxwell's equations lead to a consistent model, with distinctive energy characteristics. Numerical examples show the robustness of the approach, which is well suited for multi-scale analyses [2,3].
To improve interface adhesion between anode film and Cu foil, ultrafast laser structuring was implemented to construct dot patterns with a variety of periodic spacing (25, 50, and 75 µm) on Cu foil. The microstructure and electrochemical performance of anode films coated on those structured Cu foils were characterized. It was shown that adhesive force of the electrodes increased as periodic distance between the dots on the Cu foil decreased. Comparison of XRD patterns of the wet slurries with the dried anode films showed that after drying in the case of 50 µm period dot structured Cu foils the most graphite particles were aligned with the c-axis, vertical to the Cu foil surface. EIS, CV, and rate capability measurements confirmed that the anode film on the 50 µm dot period Cu foil had the lowest impedance, strongest lithiation and de-lithiation peaks, and highest discharge capacity. The cycling test carried out under C/2 rate confirmed that the cells with the 50 µm dot interval Cu foil showed the highest capacity retention. We inferred that this was due to the relatively shorter diffusive path in the anode due to vertical orientation of more graphite particles against the laser structured Cu foil.
Hybrid off-grid energy systems enable a cost efficient and reliable energy supply to rural areas around the world. The main potential for a low cost operation and uninterrupted power supply lies in the optimal sizing and operation of such microgrids. In particular, sudden variations in load demand or in the power supply from renewables underline the need for an optimally sized system. This paper presents an efficient multi-objective model based optimization approach for the optimal sizing of all components and the determination of the best power electronic layout. The presented method is divided into three optimization problems to minimize economic and environmental objectives. This design optimization includes detailed components models and an optimized energy dispatch strategy which enables the optimal design of the energy system with respect to an adequate control for the specific configuration. To significantly reduce the computation time without loss of accuracy, the presented method contains the determination of a representative load profile using a k-means clustering method. The k-means algorithm itself is embedded in an optimization problem for the calculation of the optimal number of clusters. The benefits in term of reduced computation time, inclusion of optimal energy dispatch and optimization of power electronic architecture, of the presented optimization method are illustrated using a case study.
This study aims to examine the effects of modelling on understanding of photosynthesis and respiration the basic reactions related to energy transformation in living organism and elimination of misconception about these topics. The study was conducted with a total of 82 students (42 experimental and 40 control groups). Success states of both group were determined by applying pre-test and the post-test containing 15 questions (Cronbach-α: 0.78) with the basic concepts related to subject and subsequently 6 questions of disclosure were asked in order to determine misconceptions. Traditional instruction method was applied to both group for explanation of energy conversion reactions in photosynthesis and respiration. Then the experimental group improved their own model. Student presented his models; subsequently the way of best modelling was discussed after the completion of all presentations. The experimental groups were more successful and have less misconception than the control group. The students have misconceptions related with particularly quality of light, ATP synthesis and electron transport system. The students think that photosynthesis is a food production mechanism and respiration is a fragmentation reactions of nutrients and these are not related to energy transformation. The application was met with interest by students, and it was thought to be useful especially in teaching of abstract concepts.