batterydata/paper-abstracts huggingface dataset:
Lithium metal is a promising anode material for its low redox potential and high theoretical specific capacity. However, issues such as dendritic growth, unstable interface and low coulombic efficiency hinder its practical applications. Construction of a porous current collector is supposed to be an effective way to address these issues and improve the cycling performances of the lithium metal battery. In this paper, commercial carbon fiber paper is used as a porous current collector for the lithium deposition, on which nanosized silver particles are plated beforehand by the silver mirror reaction. The lithiophilic silver particles alloy with the lithium and guide the subsequent lithium plating on the carbon fibers, effectively reducing the nucleation overpotential. Even at a current density of 0.5 mA cm−2, the overpotential of the lithium nucleation can still be as low as ∼21 mV. The silver particles pinned on the carbon fibers ensure the stable electrochemical cycling of the lithium plating/stripping. These prove the feasibility of using the silver-plated carbon fiber paper as a porous current collector of the lithium anode with high energy conversion efficiency and long cycling lifespan. This designing idea is of great significance for the development of the lithium metal anodes.
Heteroatom doped porous carbon flakes were prepared via carbonization of Chinese human hair fibers and employed for high-performance supercapacitor electrode materials. The morphology and chemical composition of the resultant carbon materials were characterized by electron microscopy (EM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS) measurements. Human hair carbonized at 800 °C exhibited high charge storage capacity with a specific capacitance of 340 F g−1 in 6 M KOH at a current density of 1 A g−1 and good stability over 20000 cycles. The specific capacitance of 126 F g−1 is also verified in a 1 M LiPF6 ethylene carbonate/diethyl carbonate (EC/DEC) organic electrolyte at a current density of 1 A g−1. The high supercapacitor performance could be due to the micro/mesoporosity combined with high effective surface area and heteroatom doping effects, combining double layer and Faradaic contributions.
Porous colloidal particles of LiFePO4 have been prepared using water based synthesis methods in the presence of tri-block copolymer amphiphiles. A systematic investigation into the synthesis parameters revealed the importance of porosity, particle size, crystallinity and carbon content on the electrochemical properties. Mesopore formation and particle connectivity were critical for efficient electrolyte access for high power LiFePO4 electrode materials. Samples performed well at high rates with discharge capacities of 124 mA h g−1 at 5 C and 113 mA h g−1 at 10 C achieved. Discharge capacities of 164 mA h g−1 were obtained at 0.1 C rates which are close to the theoretical capacity for LiFePO4 of 170 mA h g−1.
Solid-state cells are one of the strongest candidate designs for utilisation of renewable high-capacity organic cathode materials. Following our previous work on tetracyanoquinodimethane, further high-capacity quinonic compounds, namely dichlorodicyanobenzoquinone, tetrahydroxybenzoquinone and dihydroxybenzoquinone were investigated. Cell cycling experiments indicated that these compounds undergo reversible redox reaction with significantly less cyclic capacity decay. 3.4 V of cell voltage was attainable from DDQ cells and capacities exceeding 250 mAh g−1 were obtained from THBQ and DHBQ. These results reassure that by adopting an appropriate battery design, cycleability of organic cathodes can be drastically improved and they can be exploited as low-cost environmentally friendly high energy-density cathode materials.
This chapter discusses hydrogen-methane blends for use in the transportation industry. The use of fossil fuels in hydrogen production may limit the advantages of this technology. However, a more sustainable approach is being developed in the use of renewable sources to supply energy for electrolysis. An energetic and environmental assessment of hydro-methane is necessary to determine its sustainability, and the information collected must be used to drive technological choices.
Objectives To conduct a systematic review to elucidate the frequency, recovery, and associated outcomes for poststroke aphasia over the long-term. Data Sources Using the Cochrane Stroke Strategy, we searched 10 databases, 13 journals, 3 conferences, and the gray literature. Study Selection Our a priori protocol criteria included unselected samples of adult stroke patients from randomized controlled trials or consecutive cohorts. Two independent reviewers rated abstracts and articles for exclusion or inclusion, resolving discrepancies by consensus. Data Extraction We documented aphasia frequencies by stroke type and setting, and computed odds ratios (ORs) with their 95% confidence intervals (CIs) for outcomes. Data Synthesis We retrieved 2168 citations, reviewed 248 articles, and accepted 50. Median frequencies for mixed stroke (ischemic and hemorrhagic) were 30% and 34% for acute and rehabilitation settings, respectively. Frequencies by stroke type were lowest for acute subarachnoid hemorrhage (9%) and highest for acute ischemic stroke (62%) when arrival to the hospital was ≤3 hours from stroke onset. Articles monitoring aphasia for 1 year demonstrated aphasia frequencies 2% to 12% lower than baseline. Negative outcomes associated with aphasia included greater odds of in-hospital death (OR=2.7; 95% CI, 2.4–3.1) and longer mean length of stay in days (mean=1.6; 95% CI, 1.0–2.3) in acute settings. Patients with aphasia had greater disability from 28 days (OR=1.5; 95% CI, 1.3–1.7) to 2 years (OR=1.7; 95% CI, 1.6–2.0) than those without aphasia. By 2 years, they used more rehabilitation services (OR=1.5; 95% CI, 1.3–1.6) and returned home less frequently (OR=1.4; 95% CI, 1.2–1.7). Conclusions Reported frequencies of poststroke aphasia range widely, depending on stroke type and setting. Because aphasia is associated with mortality, disability, and use of health services, we recommend long-term interdisciplinary vigilance in the management of aphasia.
Cu2O microspheres were successfully encapsulated by graphene oxide (GO) nano-sheets and used directly as the anode material for lithium ion batteries. The core–shell structured Cu2O@GO composite delivered a reversible capacity of 458mAhg−1 at a current density of 100mAg−1 after 50 cycles. Even at a high charge–discharge rate of 1000mAg−1, Cu2O@GO still demonstrated a reversible capacity of 240mAhg−1 after 200 cycles, significantly higher than those of the bare Cu2O microspheres (37mAhg−1) and GO nano-sheets (11mAhg−1). The rate capability evaluated by the ratio of capacity at 100mAg−1/1000mAg−1 current density was 49%, 25% and 9.8% for Cu2O@GO, bare Cu2O and GO, respectively. The greatly enhanced performance for GO nano-sheets wrapped Cu2O microspheres composite mainly resulted from the synergistic effect of Cu2O microspheres and GO nano-sheets core–shell composite: the flexible in-situ electrochemically reduced GO nano-sheet coating layer functioning as an efficient three dimensional (3D) conductive network and lithium storage active material; the Cu2O microsphere core functioning as a skeleton to support multilayer GO sheets and avoid GO nano-sheets aggregation.
Nickel-rich layered-oxide materials are considered promising candidates for application as cathode material in high-energy lithium ion batteries. However, their cycling performance at high voltages and rate conditions require further improvement for the purpose of commercialization. Here, we report on the facile surface modification of nickel-rich layered oxide by chemical vapor deposition with methane which yields a conductive and protective artificial solid electrolyte interphase layer consisting of amorphous carbon, alkyl lithium carbonate, and lithium carbonate. We examine the mechanism of the protective layer formation and structural deformation of the nickel-rich layered oxide during chemical vapor deposition with methane. Via optimizing the reaction conditions, we improve the electrical conductivity as well as the interfacial stability of the nickel-rich layered oxide without inducing structural deformation. The surface-modified nickel-rich layered oxide exhibits an improved performance due to the resulting enhanced rate capability, high initial efficiency, and long cycle life at high voltage (>4.5V).
Influence of two Si-containing electrolyte additives, tris(trimethylsilyl)borate (TMSB) and tris(trimethylsilyl)phosphate (TMSP), on the cyclic stability of high voltage LiNi0.5Mn1.5O4 electrode has been systematically studied in this work. The capacity retention of LiNi0.5Mn1.5O4 cycling in STD (1M LiPF6/EC: EMC = 3:7), TMSB- and TMSP-containing electrolytes is 23%, 85% and 71% after 600 cycles at 1C rate, respectively, revealing that the ability of TMSB on improving the cyclic performance of LiNi0.5Mn1.5O4 is superior to that of TMSP. Experimental and theoretical characterizations show that the preferential reaction of both TMSB and TMSP generates thin and uniform film on LiNi0.5Mn1.5O4 surface, which effectively suppress the continuous oxidation reaction of electrolyte. While the film generated from TMSB, which contains B and Si-rich compounds, shows better ability on restraining the growth of interfacial resistance during cycling, resulting in better cyclic stability of LiNi0.5Mn1.5O4 than that of TMSP.
Single-phase Cu–Sn intermetallics were used to investigate their phase transformations during lithiation/delithiation, together with their negative-electrode properties. The stoichiometric Cu–Sn samples were prepared as thermodynamically warranted phases using a reduction-diffusion method with controlled potentials. Potentiostatic lithiation tests suggested that Cu3Sn directly changes into Li x Sn, while Cu6Sn5 becomes Li2CuSn before Li x Sn forms. We also revealed that separation from Li2CuSn into Cu and Li x Sn occurs at +0.11 to +0.10V vs. Li. Additionally, charging/discharging tests with cutoff potentials of +1.5V to +0.11V showed better cycling performance than that with +1.5V to +0.00V, probably due to the suppression of Li x Sn formation. Such a tendency can be expected in other Cu6Sn5 electrode materials.
The role of daily functioning is an integral part of the schizophrenia (SZ) phenotype and deficits in this trait appear to be present in both affected persons and some unaffected relatives; hence we have examined its heritability in our cohort of African American schizophrenia families. There is now ample evidence that deficits in cognitive function can impact family members who are not themselves diagnosed with SZ; there is some, but less evidence that role function behaves likewise. We evaluate whether role function tends to “run in families” who were ascertained because they contain an African American proband diagnosed with SZ. Methods We analyzed heritability for selected traits related to daily function, employment, living situation, marital status, and Global Assessment Scale (GAS) score; modeling age, gender, along with neurocognition and diagnosis as covariates in a family based African-American sample (N=2488 individuals including 979 probands). Results Measures of role function were heritable in models including neurocognitive domains and factor analytically derived neurocognitive summary scores and demographics as covariates; the most heritable estimate was obtained from the current GAS scores (h2=0.72). Neurocognition was not a significant contributor to heritability of role function. Conclusions Commonly assessed demographic and clinical indicators of functioning are heritable with a global rating of functioning being the most heritable. Measures of neurocognition had little impact on heritability of functioning overall. The family covariance for functioning, reflected in its heritability, supports the concept that interventions at the family level, such as evidenced-based family psychoeducation may be beneficial in schizophrenia.
Carbon-based anode materials hold a promising future for sodium-ion batteries (SIBs) due to their natural abundance and low cost of development. In spite of carbon's important role in the commercialization of lithium-ion batteries (LIBs), further exploration is necessary in order to find high-performance, high-rate carbon anode materials for SIBs. A honeycomb-like, nitrogen-rich (17.72 at%), hierarchically porous, and highly disordered carbonaceous material (N-HC) with an expanded interlayer distance (0.44 nm in average) is synthesized by spray drying and subsequent pyrolysis under flowing NH3. The hierarchically porous structure and rich nitrogen doping result in a large specific surface area (722 m2 g−1), more defects and active sites, and greater functional interface accessibility for the active porous carbonaceous material and electrolyte. When N-HC is used as the anode material for SIBs, the batteries display favorable discharge capacities (255.9 mA h g−1 in the 3000th cycle at 500 mA g−1) and good capacitive-energy-storage behavior (67% at a scan rate of 0.5 mV s−1) with excellent high-rate performance and ultra-stable cyclability over 10,000 cycles at 5000 mA g−1. Our results show that the combination of the hierarchically porous structure and nitrogen doping leads to improved energy storage by increasing the capacitive energy storage, which enhances the high-rate performance of N-HC. To further enhance the performance of the material, an electrical pretreatment is employed to increase the initial Coulombic efficiency of N-HC to 79.5%, a record high for an SIB cell. A full cell with an N-HC anode and a Na3V2(PO4)3/C cathode shows a high capacity with a favorable cyclability (238.7 mA h g−1 after 100 cycles at 100 mA g−1 and a capacity retention of 95.3% compared to the second cycle).
Semiconductor detectors whose surfaces are coated with neutron-reactive material can be made to detect thermal neutrons, but with efficiencies only of a few percent. However, perforating the semiconductor material, filling the perforations with neutron-reactive material, and then coating the detector surface can lead to neutron detectors of much higher thermal neutron detection efficiencies, perhaps approaching or exceeding 50%. Several perforated semiconductor neutron detectors have been constructed, both for dosimetry and for position-sensitive neutron detection. The characterization of prototype devices based on these detectors is described.
Two samples of produced-water collected from a storage tank at US Geological Survey research site B, near Skiatook Lake in northeastern Oklahoma, have activity concentrations of dissolved 226Ra and 228Ra that are about 1500 disintegrations/min/L (dpm/L). Produced-water also contains minor amounts of small (5–50μm) suspended grains of Ra-bearing BaSO4 (barite). Precipitation of radioactive barite scale in the storage tank is probably hindered by low concentrations of dissolved SO4 (2.5mg/L) in the produced-water. Sediments in a storage pit used to temporarily collect releases of produced-water have marginally elevated concentrations of “excess” Ra (several dpm/g), that are 15–65% above natural background values. Tank and pit waters are chemically oversaturated with barite, and some small (2–20μm) barite grains observed in the pit sediments could be transferred from the tank or formed in place. Measurements of the concentrations of Ba and excess Ra isotopes in the pit sediments show variations with depth that are consistent with relatively uniform deposition and progressive burial of an insoluble Ra-bearing host (barite?). The short-lived 228Ra isotope (half-life=5.76a) shows greater reductions with depth than 226Ra (half-life=1600a), that are likely explained by radioactive decay. The 228Ra/226Ra activity ratio of excess Ra in uppermost pit sediments (1.13–1.17) is close to the ratio measured in the samples of produced-water (0.97,1.14). Declines in Ra activity ratio (excess) with sediment depth can be used to estimate an average rate of burial of 4cm/a for the Ra-bearing contaminant. Local shallow ground waters contaminated with NaCl from produced-water have low dissolved Ra (<20dpm/L) and also are oversaturated with barite. Barite is a highly insoluble Ra host that probably limits the environmental mobility of Ra at site B.
The performance of commercial separators at high charge rates was evaluated using Li4Ti5O12 and LiMn2O4 as negative and positive electrodes, respectively. Most of the porous separators tested induced a sharp decrease in the conductivity of the liquid electrolyte. The conductivity decrease was related to the amount of porosity, polymer/electrolyte affinity, and the size of the pores and their interconnection. The decrease in conductivity induced by the separator incorporation and the separator thickness seems to be relevant indicators for optimizing a separator dedicated to high charge rate lithium-ion batteries.
We demonstrate a novel method of in situ galvanostatic polymerization to prepare reduced graphene oxide (RGO)/polypyrrole composite (RGO–PPy) for supercapacitors electrode. The PPy and the RGO interact closely and form the composite with porous structure. The BET specific surface area of RGO–PPy reaches 108m2 g−1. The RGO–PPy composites show the high protonation level on polypyrrole (PPy) ring (41.1%), which can be related to the doping of PPy by oxygen-containing groups in RGO sheet. The RGO–PPy electrodes exhibit good electrochemical performance. The specific capacitance of RGO–PPy electrodes still reaches 224Fg−1 at charge/discharge current density of 240Ag−1 within an electrochemical windows of 0.8V in 3M KCl aqueous solution. The specific power of RGO–PPy electrodes reaches 38.6kWkg−1 when its specific energy reaches 2.5Whkg−1 in two-electrode cell. The RGO–PPy electrodes have good cycle stability and show less than 17% specific capacitance decay at a charge/discharge current of 30Ag−1 within an electrochemical windows of 0.8V after 5000 cycles.
Background “Effort tests” (i.e., tests that indicate whether appropriate effort is being made) are increasingly used in neuropsychological assessments. However, not all failures on effort tests are necessarily attributable to lack of effort. Understanding the factors that contribute to failure on effort tests has important clinical implications. Objectives This study aimed (a) to establish the extent to which patients with medically unexplained symptoms (MUS) presenting to neurology fail effort tests, (b) examine the performance of “mild” and “strong” simulators on effort tests, and (c) compare the performance of simulators and MUS patients. Methods Forty-three MUS patients, 35 mild simulators, and 39 strong simulators undertook a battery of effort tests. The groups were matched for age, estimated IQ, and gender. The MUS patients were not involved in litigation. Results The failure rate (defined as failing two or more effort tests) was 11% in the MUS group, 94% in the mild simulation groups, and 100% in the strong simulation group. Conclusions A minority of nonlitigant MUS patients who present to neurology fail effort tests. Possible reasons for this are discussed. In that they do not produce below-chance performance (in contrast with many of the simulators), there is no clear indication of deliberate failure, though this cannot be ruled out. The very high failure rate in the mild simulation group (who were instructed not to overact) indicates the sensitivity of effort tests to lack of effort and the value of including such tests in neuropsychological assessments.
Xu et al. developed and characterized a new animal model of maternal immune activation based on a parasite mimetic. They show that immune and behavioral abnormalities in adult offspring are reversed by adoptive transfer of regulatory T cells.
This paper proposes a new robust controller design of heat pump (HP) and plug-in hybrid electric vehicle (PHEV) for frequency control in a smart microgrid (MG) system with wind farm. The intermittent power generation from wind farm causes severe frequency fluctuation in the MG. To alleviate frequency fluctuation, the smart control of power consumption of HP and the power charging of PHEV in the customer side can be performed. The controller structure of HP and PHEV is a proportional integral derivative (PID) with single input. To enhance the performance and robustness against system uncertainties of the designed controller, the particle swarm optimization based-mixed H 2/H ∞ control is applied to design the PID controllers of HP and PHEV. Simulation studies confirm the superior robustness and frequency control effect of the proposed HP and PHEV controllers in comparison to the conventional controller.
A composite consisting of iron oxide/graphene nanosheets (GNS) is synthesized by hydrothermal treatment of a mixture of graphitic oxide and FeCl2 in the presence of N2H4 as reducing agent. Special attention is given to the characterization of the iron oxide owing to the disparity of criteria found in literature to distinguish between maghemite (γ-Fe2O3) and magnetite (Fe3O4). Here, the oxide is accurately characterized as γ-Fe2O3. The beneficial effect of the simultaneous formation of GNS and γ-Fe2O3 is reflected in the capacity of the cell, which is much higher than those of the individual components. This may be the result of a synergistic effect of the good conducting properties of graphene, its buffering action on the volume changes undergone by γ-Fe2O3 on reacting with Li and the high capacity of this oxide. The composite also has good rate capability and can recover its capacity at low current intensities after prolonged cycling at high rates. The composite performs very well in a full cell configuration with LiFePO4 as cathode, where it exhibits an average discharge capacity of 122mAhg−1 and excellent capacity retention over 50 cycles. In addition, the cell has good rate capability at current densities as high as 5C.
Ethnopharmacological relevance Schinus molle var. areira L. (Anacardiaceae) is employed in herbal medicine for many conditions, including respiratory, urinary and menstrual disorders, and as a digestive stimulant, diuretic, astringent and antidepressant. It is also known for its topical use as wound healer, antiseptic, for skin disorders and as repellent and insecticide. In the present work, the acute dermal exposure to ethanolic and hexanic extracts from leaves of Schinus molle var. areira was studied in rats. Materials and methods A single dose of 2000mg/kg of body weight of ethanolic and hexanic extracts from leaves was applied on the shaved skin of male and female rats. After 24h of exposure, the patch was removed and any sign of irritation was recorded. Behavioral and functional parameters in a functional observational battery and motor activity in an open field were assessed after the exposure to the extracts. Then, after 14 days of observation, animals were retested. Finally, histopathological studies were conducted on several organs. Results Slight signs of erythema and edema were observed in the skin site of exposure, but they disappeared after 48h. The exposure to the hexanic extract produced an increase in parameters of activity, rearing and arousal assessed in the functional observational battery, which reversed after 14 days. On the other hand, the ethanolic extract caused an increase in locomotor activity, reflected in a higher number of rearings performed in the open field in the evaluation carried out on Day 14. No histopathological alterations were detected in the analyzed organs. Conclusions The results show that the acute dermal exposure of the ethanolic and hexanic extracts from leaves of Schinus molle var. areira only causes a slight and reversible skin irritation, and a mild stimulatory effect in rats. All these indicate that the topical use of these extracts would be safe.