batterydata/paper-abstracts huggingface dataset:
Carbon-coated layer on silicon nanoparticles (SiNPs) can improve the conductivity of SiNPs and affect the cycle performance of SiNPs based anode in lithium ion batteries. SiNPs coated with three different type of carbon (amorphous carbon, order carbon, amorphous/ordered dual carbon) are prepared and their electrochemical properties are investigated. Amorphous carbon (AC) coating shows a better conductivity, while the ordered carbon (OC) coating presents a good volume variation tolerance. Interestingly, amorphous/ordered dual carbon (AC/OC) coating structure simultaneously has the two advantages that amorphous and ordered carbons coating structures have. Hence, as an anode material in lithium ion batteries, AC/OC-coated SiNPs demonstrates an eclectic initial discharge capacity of 3300 mAhg−1 and exhibits an enhanced cycle performance that remains a discharge specific capacity of 1020 mAhg−1 at 200 cycles as well as 650 mAhg−1 after 500 cycles at the current density of 0.36 Ag−1 in the voltage range of 0.01–1.5 V. The preparation procedure of SiNPs@AC/OC is easy for large scale production and SiNPs@AC/OC can be mixed with graphite as composite anode materials for lithium ion batteries in industrial application.
The effect of nanosized silica when incorporated in polymer electrolytes is analyzed by means of Fourier transform infrared (FTIR) spectroscopy, conductivity and thermal properties. Nanocomposite polymer electrolytes are synthesized by the dispersion of nanosized silica (SiO2), up to 10wt.% maximum, into a matrix formed by poly(methyl methacrylate) (PMMA) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The highest conductivity is 2.44×10−6 Scm−1 at room temperature, with 4wt.% of silica added. The FTIR spectra show evidence of complexation between PMMA, LiTFSI and SiO2. The addition of silica to the polymer electrolytes also improves the thermal stability and the ability to retain conductivity over time.
Vanadium flow battery holds great promise for use in large scale energy storage applications. However, the power density is relatively low, leading to significant increase in the system cost. Apart from the kinetic and electronic conductivity improvement, the mass transport enhancement is also necessary to further increase the power density and reduce the system cost. To better understand the mass transport limitations, in the research, the space-varying and time-varying characteristic of the mass transport polarization is investigated based on the analysis of the flow velocity and reactant concentration in the bulk electrolyte by modeling. The result demonstrates that the varying characteristic of mass transport polarization is more obvious at high SoC or high current densities. To soften the adverse impact of the mass transport polarization, a new rectangular plug flow battery with a plug flow and short flow path is designed and optimized based on the mass transport polarization regulation (reducing the mass transport polarization and improving its uniformity of distribution). The regulation strategy of mass transport polarization is practical for the performance improvement in VFBs, especially for high power density VFBs. The findings in the research are also applicable for other flow batteries and instructive for practical use.
As a new high-voltage cathode candidate for post 4V cathodes, ordered-olivine LiCoPO4 and fluoride phosphate, Li2CoPO4F were synthesized by solid-state reaction. Their structures were identified by neutron diffraction. The 5V discharge profiles were demonstrated using coin-type cells. Two important issues for commercial use, metal dissolution and oxygen release at elevated temperatures, were also tested with an atomic absorption spectrophotometer and differential scanning calorimeter, respectively.
The impact of long-term potentiation (LTP) in nociceptive pathways on somatosensory perception was examined by means of quantitative sensory testing (QST) in the ventral forearm of 12 healthy human subjects. Electrical high-frequency stimulation of the forearm skin (HFS; 5×1s at 100Hz and 10×detection threshold) led to an abrupt increase of pain to single electrical test stimuli, which were applied through the same electrode (perceptual LTP +72%, p <0.01). Perceptual LTP outlasted the 1-h observation period. The effects of HFS on somatosensory perception of natural test stimuli in the conditioned skin area were restricted to mechanical submodalities. Subjects exhibited a significant decrease of pain threshold and an increase of pain ratings to suprathreshold pinprick stimuli (p <0.01). In 5 out of 12 subjects (42%) light tactile stimuli led to painful sensations (dynamic mechanical allodynia). Furthermore, a small but significant decrease of threshold to blunt pressure stimuli (p <0.05) was found. In contrast, all thermal modalities comprising cold and warm detection thresholds, cold and heat pain thresholds as well as pain summation (perceptual wind up) remained unaltered. These data show that HFS of peptidergic cutaneous C-fiber afferents predominantly modulates Aδ- and Aβ-fiber mediated somatosensory functions, suggesting that LTP in nociceptive pathways enhances human pain sensitivity via interaction of two afferent pathways (extrinsic sensitization).
Massive implementation of renewable energy resources is a key element to reduce CO2 emissions associated to electricity generation. Wind resources can provide an important alternative to conventional electricity generation mainly based on fossil fuels. However, wind generators are greatly affected by the restrictive operating rules of electricity markets because, as wind is naturally variable, wind generators may have serious difficulties on submitting accurate generation schedules on a day ahead basis, and on complying with scheduled obligations in real-time operation. In this paper, an innovative system combining a biomass gasification power plant, a gas storage system and stand-by generators to stabilize a generic 40MW wind park is proposed and evaluated with real data. The wind park power production model is based on real data about power production of a Spanish wind park and a probabilistic approach to quantify fluctuations and so, power compensation needs. The hybrid wind-biomass system is analysed to obtain main hybrid system design parameters. This hybrid system can mitigate wind prediction errors and so provide a predictable source of electricity. An entire year cycle of hourly power compensations needs has been simulated deducing storage capacity, extra power needs of the biomass power plant and stand-by generation capacity to assure power compensation during critical peak hours with acceptable reliability.
Since it was introduced in 2000, capsule endoscopy has become the gold standard for endoscopic examination of the small bowel in several clinical situations such as obscure gastrointestinal bleeding, suspicion of Crohn's disease, and surveillance of polyposis syndromes. In this technique a miniaturised endoscope, embedded in a swallowable capsule, is propelled through the gut by peristalsis and reaches the right colon in 5–8h. Images captured by the capsule are recorded on a hard drive in a belt worn by the patient. In addition to the extensive literature currently available on small bowel CE, new capsule devices are currently under evaluation for the examination of the colon with the purpose of screening for colorectal cancer, and of the oesophagus for screening for oesophageal varices and Barrett's oesophagus. These latter indications currently remain under evaluation. This review considers the technical aspects of capsule endoscopy and discusses the indications. Issues of safety and tolerance are also discussed.
The vanadium crossover through the membrane can have a significant impact on the capacity of the vanadium redox flow battery over long-term charge–discharge cycling. The different vanadium ions move unsymmetrically through the membrane and this leads to a build-up of vanadium ions in one-half cell with a corresponding decrease in the other. In this paper, a dynamic model is developed based on different crossover mechanisms (diffusion, migration and convection) for each of the four vanadium ions, water and protons in the electrolytes. With a simple to use approach, basic mass transport theory is used to simulate the transfer of vanadium ions in the battery. The model is validated with own measurements and can therefore predict the battery capacity as a function of time. This is used to analyse the battery performance by applying a continuous overflow from one-half cell to the other. Different overflow rates were analysed with regard to an impact of the performance and electrolyte stability. It was observed that a continuous overflow increases the capacity significantly but that the electrolyte stability plays an essential role using a membrane with a big vanadium crossover. Even with a good performance, a complete remixing of the tanks is necessary to prevent electrolyte precipitations.
The possible reasons and key factors on gas generation of Li4Ti5O12 (LTO) cells are investigated by the accelerating measurement baking at 80 °C for 120 h. It is found that the chemically catalytic reaction related to moisture makes a minor contribution to cell swelling. Our LTO-based 383450 cells (∼10 mL) before pre-charge (i.e. formation) only produce ∼1.5 mL gas during baking test and CO2, instead of H2, is the dominant species in EC/DMC electrolyte. By contrast, the swelling ratio of the charged LTO cells, which are re-sealed after formation, is kept at ∼97% regardless of states of charge. This severe decomposition of carbonates at elevated temperature should be dominated by the anode potential, rather than catalysis of LTO, since graphite/NMC cells show a similar swelling behavior at over-discharge state, where graphite anode shares the same potential as LTO. On the other hand, the electrolyte stability is also dependent on the type of solvent. Among the investigated systems, the mixture of PC + DMC (1:1) exhibits the best behavior to suppress the cell swelling. The swelling ratio diminishes from ∼100% of other electrolytes to 50%. This improvement probably roots in the high quality of protective films formed during solvents' decomposition.
Increased physical exercise improves cognitive function and reduces pathology associated with Alzheimer’s disease (AD). However, the mechanisms underlying the beneficial effects of exercise in AD on the level of specific brain cell types remain poorly investigated. The involvement of astrocytes in AD pathology is widely described, but their exact role in exercise-mediated neuroprotection warrant further investigation. Here, we investigated the effect of long-term voluntary physical exercise on the modulation of the astrocyte state.
The risk of thermal runaway is, for Li-ion batteries, a critical issue for large-scale applications. This compels manufacturers to find suitable materials or additives, which are able to minimize the heat generation and thereby mitigate safety-related risks. In an attempt to get more insight and understand the exothermic processes that take place at the negative electrode/electrolyte interface, we implemented GC/MS analytical technique to detect volatile compounds. Based on a mechanistic study, we propose a general electrolyte degradation scheme in the 100–250°C temperature range, involving electrochemically driven carbonates reduction followed by chemical reactions. The mechanisms for decomposition deduced from these analyses shed new light on the processes involved in the formation of the precipitated (SEI layer) and soluble molecules upon cell formation cycles and ageing.
Seeds of Glinus lotoides L. (Molluginaceae) are used traditionally in the treatment of tapeworm infestation in Ethiopia. Previous studies on its anthelmintic activities confirmed its traditional claims, but data on safety profile were lacking. To this effect, single and repeated dose oral toxicities of the methanolic extracts of seeds of Glinus lotoides were conducted in rats. Doses of 0, 1000 and 5000mg/kg of crude extract of Glinus lotoides were employed in single dose toxicity studies, while doses of 0, 250, 500, and 1000mg/kg were used in repeated toxicity studies. In the single dose toxicity test, oral administration of 5000mg/kg of Glinus lotoides produced mortality in two females and one male on day 4. No significant differences in body and organ weights were observed between controls and treated surviving animals. Moreover, both gross and microscopic examinations of organs did not show detectable differences between controls and treated animals of both sexes. In repeated dose toxicity studies, no mortality was observed when varying doses of the extracts were administered per day for a period of 28 days. There were no significant differences in body weight, absolute and relative organ weights between controls and treated animals of both sexes. Hematological analysis showed no differences in most parameters examined. In the biochemistry parameter analysis, no significant change occurred. Pathologically, neither gross abnormalities nor histopathological changes were observed. These finding suggest that none of the organs appeared to be target and the data could provide satisfactory preclinical evidence of safety to launch clinical trial on standardized formulation of plant extracts.
This paper is a record of the replies given by an expert panel to questions asked by delegates to the Eighth Asian Battery Conference. The subjects are as follows. Analysis of lead and lead compounds: accuracy; critical aspects of sampling. Grid alloys: influence of tin on microstructure and grain size; optimum combination of grid-alloy technologies for automotive batteries. Battery manufacture and design: quality-assurance monitoring; acid-spray treatment of plates; efficiency of tank formation; control of α-PbO2/β-PbO2 ratio; PbO2 conversion level; positive/negative plate ratio; amount and type of separator for valve-regulated technology. Battery performance: use of cadmium reference electrode; influence of positive/negative plate ratio; local action; negative-plate expanders; gas-recombination catalysts; selective discharge of negative and positive plates.
The battery state of energy (SOE) allows a direct determination of the ratio between the remaining and maximum available energy of a battery, which is critical for energy optimization and management in energy storage systems. In this paper, the ambient temperature, battery discharge/charge current rate and cell aging level dependencies of battery maximum available energy and SOE are comprehensively analyzed. An explicit quantitative relationship between SOE and state of charge (SOC) for LiMn2O4 battery cells is proposed for SOE estimation, and a moving-window energy-integral technique is incorporated to estimate battery maximum available energy. Experimental results show that the proposed approaches can estimate battery maximum available energy and SOE with high precision. The robustness of the proposed approaches against various operation conditions and cell aging levels is systematically evaluated.
LiFePO4, as the most famous member of the family of olivine-type lithium transition metal phosphates, is one of the promising candidates for the cathodes of lithium-ion batteries. However, its battery performance is limited by its low electrical conductivity and slow Li solid-state diffusion. Various methods have been attempted to improve the battery performance of lithium iron phosphate. Among them, compositing the LiFePO4 with carbon nanomaterials seems to be the most promising, as it is facile and efficient. Carbon nanomaterials usually serve as a conductive agent to improve the electrical conductivity while increasing the material porosity in which the solid-state diffusion distances are significantly shortened. Owing to the popularity of various carbonaceous nanomaterials, there is no straightforward line of research for comparing the LiFePO4/C nanocomposites. This review aims to provide a general perspective based on the research achievements reported in the literature. While surveying the research findings reported in the literature, controversial issues are also discussed. The possible contribution of pseudocapacitance as a result of functionalized carbon or LiFePO4 lattice defects is described, since from a practical perspective, a LiFePO4/C electrode can be considered as a supercapacitor at high C rates (with a specific capacitance as large as 200 F g−1). The Li diffusion in LiFePO4 has not been well understood yet; while the Li diffusion within the LiFePO4 lattice seems to be quite fast, the peculiar interfacial electrochemistry of LiFePO4 slows down the diffusion within the entire electrode by a few orders of magnitude.
Three metallic three-dimensional (3D) microporous SiC4 crystals are identified for the first time by using an unbiased structure search based on the particle-swarm optimization (PSO) algorithm combined with density functional theory (DFT) calculations, which are found to be thermally, dynamically and mechanically stable. The unusual metallicity of these three microporous SiC4 allotropes stems from the delocalized p electrons along carbon ribbons or chains. Moreover, empowered by the appropriate channel size and metallic feature, SiC4-Ⅰ manifests as a promising anode material for Na-ion batteries with theoretical capacity of 176.3 mAhg−1, diffusion energy barrier of 0.25–0.41 eV for Na ions, appropriate average open circuit voltage of 0.55 V and negligible volume change of 0.57% during charging/discharging process.
Single crystalline tin selenide (SnSe) recently emerged as a very promising thermoelectric material for waste heat harvesting and thermoelectric cooling, due to its record high figure of merit ZT in mediate temperature range. The most striking feature of SnSe lies in its extremely low lattice thermal conductivity as ascribed to the anisotropic and highly distorted Sn-Se bonds as well as the giant bond anharmonicity by previous studies, yet no theoretical models so far can give a quantitative explanation to such low a lattice thermal conductivity. In this work, we presented direct observation of an astonishingly vast number of off-stoichiometric Sn vacancies and Se interstitials, using sophisticated aberration corrected scanning transmission electron microscope; and credited the previously reported ultralow thermal conductivity of the SnSe single crystalline samples partly to their off-stoichiometric feature. To further validate the conclusion, we also synthesized stoichiometric SnSe single crystalline samples, and illustrated that the lattice thermal conductivity is deed much higher as compared with the off-stoichiometric single crystals. The scattering efficiency of individual point defect on heat-carrying phonons was then discussed in the state-of-art Debye-Callaway model.
Electrification to rural and remote areas with limited or no access to grid connection is one of the most challenging issues in developing countries like Colombia. Due to the recent concerns about the global climatic change and diminishing fuel prices, searching for reliable, environmental friendly and renewable energy sources to satisfy the rising electrical energy demand has become vital. This study aims at analyzing the application of photovoltaic (PV) panels, wind turbines and diesel generators in a stand-alone hybrid power generation system for rural electrification in three off-grid villages in Colombia with different climatic characteristics. The areas have been selected according to the “Colombia’s development plan 2011–2030 for non-conventional sources of energy”. First, different combinations of wind turbine, PV, and diesel generator are modeled and optimized to determine the most energy-efficient and cost-effective configuration for each location. HOMER software has been used to perform a techno-economic feasibility of the proposed hybrid systems, taking into account net present cost, initial capital cost, and cost of energy as economic indicators.
The tin-rich stannides BaRh5–xSn9 and BaRu5–xSn9 were synthesized by direct reactions of the elements in sealed niobium or tantalum tubes in muffle furnaces. Their structures were refined from X-ray single-crystal diffractometer data: BaCo4.7Ge9 type, Pnma, Z = 4, a = 1,553.44(8) pm, b = 438.38(2) pm, c = 1,861.5(1) pm, wR = 0.0558, 2,787 F2 values for BaRh4.43Sn9, a = 1,554.09(6) pm, b = 438.44(1) pm, c = 1,873.44(5) pm, wR = 0.0589, 2,184 F2 values for BaRh4.68Sn9, and a = 1,560.7(2) pm, b = 440.24(4) pm, c = 1,869.0(3) pm, wR = 0.0674, 2,197 F2 values for BaRu4.57Sn9 with 93 variables per refinement. The Rh5 and Ru5 sites show small defects. The shortest interatomic distances occur for Ru–Sn and Rh–Sn, leading to Ru@Sn7 and Rh@Sn7 building units that derive from an octahedron by replacing one apex by a pair of tin atoms. These units condense by common triangular and rectangular faces forming a three-dimensional network in which the barium atoms fill slightly distorted pentagonal prismatic voids.
In the present paper, we describe the Interactive Strategies approach to early reading intervention. Interactive Strategies is a first grade remedial intervention program we developed to aid in distinguishing between impaired readers whose reading difficulties are caused primarily by experiential and instructional deficits and impaired readers whose reading difficulties are caused primarily by basic deficits in reading-related cognitive abilities. We first provide a brief description of the study in which we initially implemented this program and summarize its salient findings. We then describe the theoretical model from which the instructional components of the Interactive Strategies program were derived and thereafter rationalize and describe these components. Finally, we present data supporting the relative effectiveness of the program and discuss the implications of our findings for remediating and preventing long-term reading difficulties in beginning readers.
Dual-ion batteries (DIBs) are widely studied as novel electrochemical energy storage devices in view of their low cost, environmental friendliness, and high working voltage. However, the widespread application of these batteries is hindered by organic electrolyte decomposition at high working voltages and the absence of electrode materials allowing for high capacity and long cycle lifetime, which necessitates further investigations toward performance improvement. Herein, we use 1,2-dimethyl-3-propylimidazolium chloroaluminate (DMPI+)(AlCl4 −) as an ionic liquid electrolyte and graphite rods as electrodes to fabricate a DIB with excellent electrochemical performance, revealing that the redox amphotericity of carbon allows the intercalation/deintercalation of both cations and anions into/from the graphite electrodes. The developed DIB is shown to exhibit high discharge voltage plateaus of 4.2–4.0 and 3.6–3.1 V, a reversible specific capacity of ∼80 mAh g−1 at a current density of 300 mA g−1, and a high coulombic efficiency of ∼97% over 300 cycles. Moreover, the non-flammability and electrochemical stability of the employed electrolyte result in improved safety and performance, allowing the fabricated DIB to function under various critical conditions such as high C-rate charge/discharge, continuous bending, and even burning. Thus, the developed battery is concluded to hold great promise for grid energy storage and other applications.