batterydata/paper-abstracts huggingface dataset:
Exploring low-cost, facile, and scalable fabrication procedure for silicon/carbon composite with excellent electrochemical performance is urgently required to promote the practical application of high-capacity silicon material for Li-ion battery anodes. Using commercial cost-effective AlSi alloy nanopowder as the silicon source, here we present a facile approach via pre-template-coating and chemical acid etching methods for synthesizing silicon/porous nitrogen-doped carbon composite with a unique core-porous shell structure. At the pre-template-coating stage, the AlSi alloy nanopowder is initially coated by carbon via the solution deposition and carbonization of PVP. The Al template is subsequently removed by acid etching, affording silicon nanoparticles wrapped by the highly conductive nitrogen-doped carbon. The escape of hydrogen gas during acid etching leads to the nitrogen-doped carbon shell with a microporous structure. The silicon/porous nitrogen-doped carbon composite with 88% Si delivers a high reversible capacity of 1730mAhg−1 (based on the total mass of the composite) after 100 cycles at a current density of 1000mAg−1 with a coulombic efficiency of approximately 100%. Moreover, the rate capability is significantly improved. With the increase in the current density from 200 to 500, 1000, 2000 and 3000mAg−1, high capacity retention values of 99.7, 97.5, 93.7 and 91.5%, respectively, are obtained. A long cycle life at a high rate is also achieved, with a notable capacity of 665mAhg−1 after 600 cycles at a high current density of 5000mAg−1. The low-cost, facile, and scalable synthesis of the approach silicon/porous nitrogen-doped carbon composite with exceptional electrochemical performance from a commercial AlSi alloy powder makes it extremely promising as a practical anode material for high-energy Li-ion batteries.
Despite the preponderance of evidence on the numerous benefits of CR, it remains largely under-utilized in women. The objective of this narrative review was to summarize and synthesize the literature on women and CR with regard to outcomes, adherence, and preferences for alternative models of CR. Studies of the effectiveness of CR have generally revealed no major differences between men and women. However, female-specific data are lacking on the effect of CR on mortality and morbidity. Research suggests that women and men may be equally likely to prefer home-based to hospital-based CR services. Women's preferences for and outcomes in, women-only CR are beginning to be uncovered. Discussing program model options with female cardiac patients and referring to preferred types may be the appropriate approach until further evidence is available.
CuO nanoleaves on graphene sheets (CuO/GNS) composite was successfully synthesized by a facile microwave-assisted method using Cu(NO3)2·3H2O, NaOH and ammonia as raw materials and absolute ethanol as solvent. The structure and morphology were characterized by XRD, SEM, TEM, HRTEM. The electrochemical performance was measured by cyclic voltammetry (CV), galvanostatic charge and discharge measurements and AC impedance test. The results revealed that the leaf-shaped rhombic CuO were uniformly dispersed on GNS with a width of 40nm in the middle and a length of 100-140nm. As an anode material for Li-ion battery, the CuO/GNS composites showed enhanced electrochemical performance with high lithium storage capacity, satisfactory cyclic durability and rate capacity than pristine CuO. The reversible capacity of the CuO/GNS composites retained 600 mAh g−1 after 50 cycles at 100mAg−1. Even when cycled at various rates for 50 cycles, the capacity could recover to 600 mAh g−1 at the current of 100mAg−1. The excellent electrochemical performance was ascribed to the synergy effect of the uniformly distributed CuO nanoleaves and graphene sheets. The CuO nanoleaves between the graphene sheets effectively kept the neighboring graphene sheets separated, and graphene effectively prevented aggregation and pulverization of CuO nanoleaves. The overall electrode was highly conductive, and the stability of the structure was maintained.
An electrolyte composed of lithium difluoro(oxalate)borate (LiDFOB) as lithium salt, N-propyl-N-methylpiperidinium bis(trifuoromethansulfonyl) imide (PP13TFSI) ionic liquid and dimethylcarbonate (DMC) as co-solvent and fluoroethylene carbonate (FEC) as additive is reported in this study. It is found that the resulted ionic liquid-based electrolyte demonstrates high ionic conductivity, low polarization and high safety performance. The Li/Li1.1Ni0.25Mn0.65O2 and Li/Graphite half-cells with the electrolyte exhibit excellent electrochemical performance, retaining capacities of more than 186 mA h g−1 and 361.6 mA h g−1 after 100 cycles, respectively. Such outstanding energy storage performance is ascribed to the joint oxidative decomposition of LiDFOB and FEC, which can form stable and low impedance solid electrolyte interface (SEI) on the Li-rich cathode and graphite anode. Besides, the SEI layer can prevent transition metal dissolution, enabling excellent cycling stability for the high voltage graphite/Li1.1Ni0.25Mn0.65O2 full cell. As a result, the full cell with the ionic liquid based electrolyte maintains a discharge capacity and capacity retention of 180 mAh g−1 and 87.54% after 100 cycles at 0.5 C and 40 °C, far superior to that obtained for commercial electrolyte. All these characteristics make the electrolyte a promising candidate for safe, high performance lithium-ion battery electrolyte.
Unfortunately, over 40% of stroke victims have pre-existing diabetes which not only increases their risk of stroke up to 2–6 fold, but also worsens both functional recovery and the severity of cognitive impairment. Our lab has recently linked the chronic inflammation in diabetes to poor functional outcomes and exacerbated cognitive impairment, also known as post-stroke cognitive impairment (PSCI). Although we have shown that the development of PSCI in diabetes is associated with the upregulation and the activation of pro-inflammatory microglia, we have not established direct causation between the two. To this end, we evaluated the role of microglia in the development of PSCI.
Nanocomposite polymer electrolytes based on poly (ethylene) glycol (PEG) complexed with lithium perchlorate (LiClO4) salt and SrBi4Ti4O15 (SBT), a ferroelectric ceramic material, as filler are prepared and characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), differential thermal analysis (DTA) and impedance spectroscopic techniques. An enhancement in conductivity is observed with the addition of SBT as filler to the PEG: LiClO4 salt complex. The PEG: 1.0(LiClO4)+12.5 SBT (ball-milled) polymer nanocomposite exhibits maximum room temperature conductivity of 2.4320×10−6 Scm−1.
A large number of stand-alone power systems that are based on fossil fuel or renewable energy (RE) based, are installed all over Europe. Such systems, often comprising photovoltaics (PV) and/or diesel generators provide power to communities or technical installations, which do not have access to the local or national electricity grid. The replacement of conventional technologies such as diesel generators and/or batteries with hydrogen technologies, including fuel cells in an existing PV-diesel stand-alone power system providing electricity to a remote community was simulated and optimised, using the hybrid optimisation model for electric renewables (HOMER) simulation tool. A techno-economic analysis of the existing hybrid stand-alone power system and the optimised hydrogen-based system was also conducted. The results of the analyses showed that the replacement of fossil fuel based gensets with hydrogen technologies is technically feasible, but still not economically viable, unless significant reductions in the cost of hydrogen technologies are made in the future.
Carbon-coated LiTi2(PO4)3 (LTP/C) nano- and/or microcrystals have been subjected to extensive research due to their potential application in aqueous rechargeable lithium-ion batteries (ARLBs) with enhanced electrochemical performance. In this paper, mesoporous LTP/C nanocrystals have been prepared by annealing the precursor obtained through a simple room-temperature co-precipitation method. The mesoporous LTP/C nanocrystals have been evaluated in the role of anode materials for lithium-ion batteries (LIBs) with organic and water electrolyte, respectively. After 1000 cycles at 5 and 20C, the specific discharge capacity of the LTP/C electrode with organic electrolyte retains 116.9 and 80.4mAhg−1, with capacity retention of 94.4% and 80.4%, respectively. After 1000 cycles at 1.37C, the specific discharge capacity of the LTP/C‖LiMn2O4 pouch cells with 1molL−1 Li2SO4 electrolyte retains 20.1mAhg−1, presenting a discharge voltage plateau around 1.21V and a capacity retention of 71.5%. The enhanced electrochemical performance of the mesoporous LTP/C nanocrystals makes them a promising candidate functioning as anode materials for LIBs and hybrid supercapacitors.
LiCoO2 and LiCuxAlyCo1−x−yO2 (x = 0.05–0.15; y = 0.05–0.15) powders have been synthesized by sol–gel method using malic acid as chelating agent to obtain sub-micron sized particles. The synthesized samples have been subjected to spectral studies viz., differential thermal analysis (TG/DTA), fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX) and electrochemical characterization. XRD peak reflections of LiCoO2 and LiCuxAlyCo1−x−yO2 exhibit high degree of crystallinity with better phase purity. SEM images of LiCoO2 exhibit an ice cube surface morphology with grains size of 1.5 μm. Doped lithium cobalt oxide shows surface morphology of uniform particle size 2 μm. EDAX peaks confirm the actual composition of Cu, Al, Co and O in LiCoO2 and LiCuxAlyCo1−x−yO2. Charge–discharge studies of undoped LiCoO2 synthesized by sol–gel method deliver maximum an initial discharge capacity of 127 mA h g−1 which corresponds to columbic efficiency of 65 % during the first cycle with capacity fade of 0.13 mA h g−1 cycle−1 over the investigated 10 cycles. Cu and Al doping LiCoO2 exhibit the capacity fade of 0.06, 0.16, 0.14, 0.13 and 01.3 mA h g−1 cycle−1 over the investigated 10 cycles corresponding to columbic efficiency of 74, 75, 73, 73 and 71 with capacity fade of 2, 3, 2, 2, and 2 mA h g−1 cycle−1 at the 10th cycles for Cu: Al doping of 0.1:0.1, 0.13:0.07, 0.07:0.13, 0.15:0.05, and 0.05:0.15 respectively.
This paper reports the state of art on fuel cells technology, outlines the most significant results reached all over the world and summarises the strategies developed by researchers and producers to get the commercialisation of these systems. In particular, the authors have examined three potential application fields for fuel cells: (i) stationary power plant for electricity production; (ii) portable power applications; (iii) electric vehicles. The potential market area for each sector of application has been defined and the research activity necessary to overcome the technical problems that are still open have been detailed. The significant projects of main fuel cells producers are also mentioned.
Microelectromechanical systems also known as MEMS are used in various small-scale sensor applications. A new trend is witnessed in the MEMS industry called “system on a chip”. The goal is to develop a chip with a sensor, an actuator and power source and power storage device all on one chip. LiMn2O4 thin films show great promise as providers of power to these sensors and actuators on a silicon chip. These batteries are required to have high power density, high charge and discharge rate capability, long cycle life and reduced capacity fading. To demonstrate these features pulsed laser deposition (PLD) and the laser spark atomization (LSA) techniques were used to deposit LiMn2O4 films on various substrate materials. The thin (<0.2μm) films grown by PLD were highly crystalline and textured along either (111) or (001) direction depending on the substrate type. Films grown by LSA were much thicker (>1μm) and exhibited a porous structure consisting of a mixture of randomly oriented nanocrystals embedded in an amorphous matrix. The effect of these two different microstructures on the electrochemical properties of the LiMn2O4 thin films has been investigated. The results obtained indicate that differences in film structure and particle morphology have a significant impact upon electrochemical kinetics of Li ion intercalation and de-intercalation.
With the increasing numbers of cardiac implantable devices in use, lead extraction has become a critical procedure in remedying device-related infections and complications. Lead extraction technology has grown considerably over the past two decades from simple traction maneuvers to the use of powered, telescoping sheaths equipped with laser technology. Data from single center experiences and randomized control trials have continued to demonstrate the safety and efficacy of the most current lead extraction technology. Still, major complications occur in less than 1% of patients. Patient preparation and in-place laboratory protocols are important for the prevention of complications and the rapid diagnosis and treatment of life-threatening complications should they arise.
A common practise in the research of Li–S batteries is to use high electrode porosity and excessive electrolytes to boost sulfur-specific capacity. Here we propose a class of dense intercalation-conversion hybrid cathodes by combining intercalation-type Mo6S8 with conversion-type sulfur to realize a Li–S full cell. The mechanically hard Mo6S8 with fast Li-ion transport ability, high electronic conductivity, active capacity contribution and high affinity for lithium polysulfides is shown to be an ideal backbone to immobilize the sulfur species and unlock their high gravimetric capacity. Cycling stability and rate capability are reported under realistic conditions of low carbon content (~10 wt%), low electrolyte/active material ratio (~1.2 µl mg−1), low cathode porosity (~55 vol%) and high mass loading (>10 mg cm−2). A pouch cell assembled based on the hybrid cathode and a 2× excess Li metal anode is able to simultaneously deliver a gravimetric energy density of 366 Wh kg−1 and a volumetric energy density of 581 Wh l−1.
Phase change material (PCM)-based heat sinks have the potential to provide reliable thermal management for electronic devices. However, the low thermal conductivity of PCMs hampers their use in large-volume or high-power devices. Embedding a PCM in a porous matrix is an efficient method for enhancing heat dissipation in a passive cooling application. In this study, the copper fibers with ample antler microstructures on their surface were first introduced into the phase change heat transfer enhancement technology. The enhanced heat transfer performance of a PCM embedded in a porous metal fiber sintered felt (PMFSF) was experimentally investigated. Paraffin/PMFSF composite PCM (MF-PCM) was prepared, and three types of heat sinks (filled with MF-PCM, filled with paraffin, and empty) were tested under four power levels. The effect of the porosity was also investigated. It was found that the addition of PMFSF enhanced heat transfer to the PCM, leading to lower heat source temperature. The improvement of heat transfer by MF-PCM is more evident under larger heat flux. Before melting is completed, lower heat source temperature and temperature gradient is achieved for the heat sink with low porosity, while longer duration of temperature control region is achieved in the case of the heat sink with the higher porosity. The time-averaged effective thermal resistance of the heat sink with paraffin is higher than that of the heat sinks with MF-PCM. All these results show the enormous potential of using PMFSF to replace metal foams, thus offering a new porous metal matrix to enhance the thermal conduction of PCMs.
Emerging trends in mobile edge computing for developing the efficient healthcare application such as, remote monitoring of the patients with central electronics clouds (e-Clouds) and their increasing voluminous multimedia have caught the attention of everyone in industry and academia. So, clear visualization, big sensing level, and better quality of service (QoS) is the foremost priority. This paper proposes the window-based Rate Control Algorithm (w-RCA) to optimize the medical quality of service (m-QoS) in the mobile edge computing based healthcare by considering the network parameters for instance, peak-to-mean ratio (PMR), standard deviation (Std.dev), delay and jitter during 8 min medical video stream named “Navigation to the Uterine Horn, transection of the horn and re-anastomosis’ transmission over 5 G networks. The performance of the proposed w-RCA is evaluated and compared with the conventional battery smoothing algorithm (BSA) and Baseline by using MPEG-4 encoder for optimizing m-QoS at the source or the server side. The experimental results demonstrate that the w-RCA outperforms the BSA and Baseline by optimizing QoS in remote healthcare application i.e., Tele-surgery. Besides, it is observed and analyzed that w-RCA produces better and effective results at small buffer and window sizes unlike BSA and Baseline by adopting large buffer size during QoS optimization.
Cell behavior is numerically investigated for fast charging of a lead–acid cell under constant current or pulsed current. A model used in the simulation has been developed to predict the cell performance by considering the solid-state reaction at the negative electrode. By incorporating a rest period and a depolarization pulse on high rate charge, it is possible to avoid deterioration of the cell performance due to an increase in internal resistance. Thus, fast charging of a lead–acid cell can be achieved without a loss of cycle-life, despite the fact that higher currents are forced into the cell.
The intrinsic poor electrical and large volume expansion upon cycling of ZnO raise up challenging kinetic issues. In this work, ZnO@TiO2 core/shell nanorod arrays heterostructure grown directly on carbon cloth is designed and fabricated. The atomic layer deposition coated TiO2 thin layer can not only function as an efficient stress buffer during electrochemical reaction, but also provide enhanced electronic conductivity by forming a heterostructure with ZnO. The ZnO@TiO2 nanorod arrays on carbon cloth can simultaneously achieve the high capacity and high-rate long cycle life (1000 mA h/g for 250 cycles at 1 A/g), which is far superior to that of bare ZnO nanorod arrays on carbon cloth without TiO2 shell. The density functional theory calculations reveal the strong chemical coupling between ZnO and TiO2, which realizes band gap tailoring and significant charge redistribution of both ZnO and TiO2. Such a unique structure endows the as prepared ZnO@TiO2 on carbon cloth great potential as high performance three-dimensional flexible electrode in Li-ion batteries.
To date, there has been a dearth of scientifically tested, established intervention concepts focussed on supporting informal caregivers and embedded in routine health care structures. The aim of this study was to assess effects of a brief telephone intervention for caregivers of persons with cognitive impairment (PCIs) on caregivers’ depressiveness and subjective burden.
Amorphous cobalt–boron (Co–B) with uniform nanoparticles was prepared for the first time via reduction of cobalt acetate by potassium borohydride in the water/cetyl-trimethyl-ammonium bromide/n-hexanol microemulsion system. The sample was characterized by X-ray diffraction, transmission electron microscopy, nitrogen adsorption–desorption, X-ray photoelectron spectroscopy, inductively coupled plasma, cyclic voltammetry, differential scanning calorimetry, temperature-programmed desorption, scanning electron microscopy, charge–discharge test and electrochemical impedance spectra. The results demonstrate that electrochemical activity of the as-synthesized Co–B was higher than that of the regular Co–B prepared in aqueous solution. It indicates that the homogeneous distribution and large specific surface area helped the electrochemical hydrogen storage of the as-synthesized Co–B. Furthermore, the as-synthesized Co–B even had 347mAhg−1 after 50 cycles, while the regular Co–B prepared in aqueous solution only had 254mAhg−1 after 30 cycles at a current of 100mAg−1. The better cycling performance can be ascribed to its smaller interfacial impedance between electrode and electrolyte.
Characterizing and mapping the relationship between neuronal reorganization and functional recovery are essential to the understanding of cerebral plasticity and the dynamic processes which occur following brain damage. The neuronal mechanisms underlying linguistic recovery following left hemisphere (LH) lesions are still unknown. Using functional magnetic resonance imaging (fMRI), we investigated whether the extent of brain lateralization of linguistic functioning in specific regions of interest (ROIs) is correlated with the level of linguistic performance following recovery from acquired childhood aphasia. The study focused on a rare group of children in whom lesions occurred after normal language acquisition, but prior to complete maturation of the brain. During fMRI scanning, rhyming, comprehension and verb generation activation tasks were monitored. The imaging data were evaluated with reference to linguistic performance measured behaviorally during imaging, as well as outside the scanner. Compared with normal controls, we found greater right hemisphere (RH) lateralization in patients. However, correlations with linguistic performance showed that increased proficiency in linguistic tasks was associated with greater lateralization to the LH. These results were replicated in a longitudinal case study of a patient scanned twice, 3 years apart. Additional improvement in linguistic performance of the patient was accompanied by increasing lateralization to the LH in the anterior language region. This, however, was the result of a decreased involvement of the RH. These findings suggest that recovery is a dynamic, ongoing process, which may last for years after onset. The role of each hemisphere in the recovery process may continuously change within the chronic stage.
Traditionally electrodes for lithium ion batteries are manufactured using carbon additives to increase the conductivity. However, in case of lithium titanate, Li4Ti5O12 (LTO), carbon free electrodes have gathered some interest lately. Therefore two LTO materials synthesized using the same synthesis but different end milling process resulting in materials with different particle size and surface area are compared here using electrodes manufactured with and without carbon additives. Both LTO samples (LTO-SP with small primary particle size and high surface area, and LTO-LP with larger primary particle size and small surface area) produce similar capacities and voltages with or without carbon additives at low C-rates at the room temperature. However, at high C-rates and/or sub-zero temperatures electrodes with carbon additives produce higher capacities and smaller ohmic losses and this behavior is more pronounced for the LTO electrodes with smaller primary particle size and larger surface area. These results show that the feasibility of carbon free LTO electrodes depends on the properties of LTO affecting the morphology of the electrode and consequently, the transport properties. This is most pronounced under conditions where electron and Li+ ion transfer become limiting (high C-rates and low temperature).
An unexpected dissociation between intact propositional speech and impaired language comprehension was observed in a right handed patient following a right hemisphere stroke. Although CHO's comprehension was intact at the single word level, his ability to comprehend a wide range of sentence structures was profoundly impaired. This deficit was observed in the context of normal sentence production both with regard to semantic and syntactic content. This case provides further evidence for the independence of on-line language input and output systems.