batterydata/paper-abstracts huggingface dataset:
For the first time, octagonal prism shaped lithium iron phosphate (LiFePO4) composite particles supported on the multi-walled carbon nanotubes (MWNTs) (denoted as OP-LiFePO4/MWNTs) are prepared by using a boiling reflux assisted calcination method. Interestingly, spherical LiFePO4 composite particles (indexed as S-LiFePO4/C) are produced by the same procedure in the presence of activated carbon. It is observed that the edge length of OP-LiFePO4 particles is about 400nm as compared to the particle size of S-LiFePO4 (∼150nm) sample. Cyclic voltammetry (CV) tests demonstrate that at the scan rate of 0.5 mVs−1 the potential separation of the OP-LiFePO4 sample (about 250mV) is much smaller than that of S-LiFePO4 (about 443mV). More importantly, the initial discharge capacities at 0.1 and 1.0C for the OP-LiFePO4/MWNTs are 160.58 and 116.71 mAhg−1, higher than that of S-LiFePO4/C (151.29 and 95.69mAhg−1 at 0.1 and 1.0C).
Background Deep brain stimulation (DBS) is an effective treatment for essential tremor (ET) and dystonia. After surgery, a number of extensive programming sessions are performed, mainly relying on neurologist's personal experience as no programming guidelines have been provided so far, with the exception of recommendations provided by groups of experts. Finally, fewer information is available for the management of DBS in ET and dystonia compared with Parkinson's disease. Objective/hypothesis Our aim is to review the literature on initial and follow-up DBS programming procedures for ET and dystonia and integrate the results with our current practice at Toronto Western Hospital (TWH) to develop standardized DBS programming protocols. Methods We conducted a literature search of PubMed from inception to July 2014 with the keywords “balance”, “bradykinesia”, “deep brain stimulation”, “dysarthria”, “dystonia”, “gait disturbances”, “initial programming”, “loss of benefit”, “micrographia”, “speech”, “speech difficulties” and “tremor”. Seventy-six papers were considered for this review. Results Based on the literature review and our experience at TWH, we refined three algorithms for management of ET, including: (1) initial programming, (2) management of balance and speech issues and (3) loss of stimulation benefit. We also depicted algorithms for the management of dystonia, including: (1) initial programming and (2) management of stimulation-induced hypokinesia (shuffling gait, micrographia and speech impairment). Conclusions We propose five algorithms tailored to an individualized approach to managing ET and dystonia patients with DBS. We encourage the application of these algorithms to supplement current standards of care in established as well as new DBS centers to test the clinical usefulness of these algorithms in supplementing the current standards of care.
Rhenium disulfide (ReS2) has recently amassed increasing interests as lithium-ion batteries (LIBs) anode material due to its extremely weak interlayer coupling and high Li storage capacity. However, its potential as high-performance sodium-ion batteries (SIBs) has rarely been explored comprehensively. In this work, we demonstrate a novel construct of ReS2 anode consisting of vertical ReS2 nanosheets uniformly grown on metal-organic framework (MOF) derived porous carbonaceous nanocubes (RESNC), is able to achieve high-performance SIBs. Exhibiting high specific surface area (117.40 m2 g−1) and near-microporous (∼2.20 nm) pore size distribution, this unique and conductive nanostructure provides abundant reactive sites which enable rapid and efficient ions/electrons transportation. For the first time, the sodiation/desodiation redox mechanisms of the ReS2-based nanostructure are revealed via ex situ investigations. Our results demonstrated that RESCN nanocomposite is endued with high capacity (365 mA h g−1, 100 mA g−1), high rate capability (up to 2 A g−1) and stable cycling performance (>600 cycles, 2 A g−1). To elaborate on the rate and cycling capabilities, various diffusion pathways of sodium-ions on the ReS2 lattice were unravelled via first-principles/ab initio techniques, with the results indicating favourable diffusion mechanics. Through the joint approach of comprehensive experimental and theoretical investigations, our results suggest that the ReS2/C composites are highly promising as high-performance SIBs anode materials, as well as broadening the current perspectives of materials choices as far as high capacity transition metal disulfides (TMDs) is concerned.
The promise of redox flow batteries (RFBs) utilizing soluble redox couples, such as all vanadium ions as well as iron and chromium ions, is becoming increasingly recognized for large-scale energy storage of renewables such as wind and solar, owing to their unique advantages including scalability, intrinsic safety, and long cycle life. An ongoing question associated with these two RFBs is determining whether the vanadium redox flow battery (VRFB) or iron-chromium redox flow battery (ICRFB) is more suitable and competitive for large-scale energy storage. To address this concern, a comparative study has been conducted for the two types of battery based on their charge–discharge performance, cycle performance, and capital cost. It is found that: i) the two batteries have similar energy efficiencies at high current densities; ii) the ICRFB exhibits a higher capacity decay rate than does the VRFB; and iii) the ICRFB is much less expensive in capital costs when operated at high power densities or at large capacities.
The dissolution behaviors of manganese and chromium-ions of LiMn2−x Cr x O4 have been investigated at various temperatures. When the LiMn2−x Cr x O4 powders were soaked in the LiPF6-containing electrolyte, the dissolution of manganese-ions as well as chromium-ions took place. With an increase of chromium-ions in LiMn2−x Cr x O4, the amounts of dissolved manganese-ions significantly decreased at room and elevated temperatures. This indicates that doping chromium-ions in LiMn2O4 can suppress the dissolution reaction of manganese-ions at elevated temperatures, thereby leading to lowered degree of capacity deterioration. On the other hand, raising the immersion temperature significantly increased the amounts of dissolved manganese and chromium-ions. It was also demonstrated that operation temperatures play an important role in the dissolution in both undoped and chromium-ion doped LiMn2O4.
PILs are emerging as promising materials for CO2 capture. Film formation, which is a requisite for membrane formation, is induced in a family of PILs by N-substituting a rigid thermo-mechanically stable polybenzimidazole, followed by metathesis. This provided two IL groups per repeat unit of the PIL and enhanced the CO2 separation characteristics.
For addressing the critical problems in current collectors in the aluminium batteries, a variety of carbon-based current collectors, including carbon fiber textiles and three-dimensional (3D) biomass-derivative carbon (BDC) networks, are employed for serving as lightweight non-metal current collectors. The results indicate that all the carbon-based current collectors have electrochemical stability in the acidic electrolyte environments. In the assembled aluminium batteries with all-carbon positive electrodes, thermal annealing process on the carbon-based current collectors has substantially promoted the entire electrochemical energy storage performance. Additionally, both the structure configuration and chemical components of the current collectors have also great impact on the rate capability and cycling stability, implying that the 3D BDC networks are more favorable to offer promoted energy storage capability. Implication of the results from suggests that the carbon-based current collectors and all-carbon positive electrodes are able to deliver more advantages in energy storage behaviors in comparison with the traditional positive electrodes with metal Mo current collectors. Such novel strategy promises a new route for fabricating high-performance positive electrodes for stable advanced aluminium batteries.
The electrochemical behavior of a composite anode based on tin oxide nanoparticles embedded in electrically conductive graphene matrix is reported. The composite has been synthetized through microwave reduction of poly acrylic acid functionalized graphene oxide and a tin oxide organic precursor both dispersed in ethylene glycol. The poly acrylic functionalization of graphene oxide partially prevent the re-stacking of the graphene layers. In addition, poly acrylic acid acts as a surfactant favoring an optimized dispersion of the metal and, after thermal decomposition, contributes in creating a carbon layer for an improved conductivity. The final product morphology reveals a composite in which SnO2 nanoparticles are homogenously distributed into the reduced graphene oxide matrix. Graphene/SnO2nanocomposite electrodes, prepared using Super-P carbon as conducting additive and polyvinylidenedifluoride as binder, exhibit high rate capability and cycle life during galvanostatic charge/discharge tests. After more than 140 cycles, mostly performed at 500mAg−1, the electrodes show a remarkable stable specific capacity of about 430 mAh g−1with a Coulombic efficiency close to 100%.The morphological stability of the electrode is also confirmed by impedance spectroscopy analysis, which shows solid-electrolyte interphase related resistance values constant up to 100 cycles.
New conductive materials involving Cu+ ions are proposed for electrochromic devices. They are liquid ammoniates which can be used from room temperature up to 80°C, and whose conductivity and p(NH3) can be modulated according to requirements. The synthesis does not require strong acids or complexing agents such as halide ions. The principle of operation of the electrochromic material is the reduction of Cu+ to Cu at the transparent cathode while Cu+ is oxidized to Cu2+ (thus developing a blue color) at the transparent anode. The bleaching is realized by the reverse reactions.
The chemical composition of the pristine passivation layer formed on the surface of commercial lithium foils has been investigated by polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) and confocal Raman microspectrometry (CRM). Carbonates and hydroxides are easily detected by PM-IRRAS and on-line non-destructive analysis could be envisaged with this technique or even with the simpler IRRAS technique in dry atmosphere. On the other hand, local heating under laser irradiation is difficult to avoid in CRM. It transforms carbonate species into lithium acetylides of the Li2C2 type characterized by a νCC line at ca. 1845cm−1. This might explain an unexpected Raman line observed at 1830–1850cm−1 in previous literature studies of the lithium/electrolyte interface or of the carbon/electrolyte interface in lithium-ion batteries.
Progress in understanding the genetic etiology of autism spectrum disorders (ASD) has fueled remarkable advances in our understanding of its potential neurobiological mechanisms. Yet, at the same time, these findings highlight extraordinary causal diversity and complexity at many levels ranging from molecules to circuits and emphasize the gaps in our current knowledge. Here we review current understanding of the genetic architecture of ASD and integrate genetic evidence, neuropathology and studies in model systems with how they inform mechanistic models of ASD pathophysiology. Despite the challenges, these advances provide a solid foundation for the development of rational, targeted molecular therapies.
With the surge in the fossil fuel prices and increasing environmental concerns, significant efforts have been made to propel and develop alternative energy technologies to cope with the energy shortage for island power grids. Recent advancements and developments on power electronic technologies have enabled the renewable energy sources to be grid-connected with gradually higher penetration in island electricity supply. Consequently, the utilization and efficiency of renewable energy resources in islands has received remarkable attention from both the academia and industry. In this paper, a brief overview on the current status of island energy resources is described. Then, the existing utilization status and development potential of various renewable generations for island power grids, including solar, wind, hydropower, biomass, ocean and geothermal energy, are investigated. Furthermore, the advanced technologies to improve the penetration level of island renewables, including energy storage techniques, hybrid renewable energy system, microgrid, demand side management, distributed generation and smart grid, are presented.
This work reports on the in-situ chemical synthesis and their properties of the core (active material)/shell (conductive material) type Co3O4/graphene quantum dots (QDs). The stable oxygen bridge bonds between the Co3O4 core and the oxygen-related functional groups on the graphene shells facilitate the efficient charge/discharge performance. The efficient electron transfer process between the Co3O4 core and the graphene shell lead to an improvement in the electrochemical activity. The specific capacitances of Co3O4/graphene QDs electrode, without conductive additives, exhibit high values of 2435 F g−1 at current densities of 1 A g−1. It breaks through 126% of the initial capacitance after 500 cycles and show above 112% even after 4500 cycles. The excellent performance of the Co3O4/G QDs electrode is attributed to the significant improvement of the electrochemical activity, without conductive additives, due to the presence of metal oxide QD covered by graphene shells which leads to the good electrical properties.
Two potential pathways for Li+ diffusion occur within graphitic carbon with typically in-plane diffusion dominating (∼10−7 cm2 s−1) over diffusion along the crystallite grain boundaries (∼10−11 cm2 s−1). Reducing the flake thickness of microcrystalline graphite powders via electrochemical exfoliation offers a method to overcome the latter, sluggish grain boundary Li+ diffusion, thereby increasing the overall rate capability of the graphite negative electrode in a the Li-ion battery. Six micron particulate graphite was electrochemically exfoliated to give flakes of which ∼90% had a thickness of <10 graphene layers. This exfoliated material was then prepared as an ink and allowed to dry prior to forming a battery electrode. Analysis of the electrode and dried exfoliated powder using powder X-ray diffraction, scanning electron microscopy and Brunauer–Emmett–Teller isotherm analysis show that the material has, apart from a significant reduction of the rhombohedral fraction from 41% to 14%, near-identical properties to that of original starting graphite powder. Thus, once the exfoliated powder has been dried from the exfoliation process, as anticipated, major restacking of the multi-layer graphene flakes had occurred. Likewise there was no significant improvement in using the exfoliated material at high rates of delithiation and lower specific capacity, when tested within a half cell vs. lithium metal. In situ Raman analysis showed that the exfoliated material displayed similar spectral features to the pristine sample during lithiation, as did multi point measurements on differently disordered areas shown from the varying ID /IG -band intensity ratios, indicating that local surface disorder does not influence the course of lithium insertion. The re-aggregation of graphenic material is widely recognised, but seldom evaluated. This work shows the importance of keeping graphenic material dispersed at all stages of production.
The paper aims at characterizing the electrochemical and thermal parameters of a 15 kW/320 kWh vanadium redox flow battery (VRB) installed in the SYSLAB test facility of the DTU Risø Campus and experimentally validating the proposed dynamic model realized in Matlab-Simulink. The adopted testing procedure consists of analyzing the voltage and current values during a power reference step-response and evaluating the relevant electrochemical parameters such as the internal resistance. The results of different tests are presented and used to define the electrical characteristics and the overall efficiency of the battery system. The test procedure has general validity and could also be used for other storage technologies. The storage model proposed and described is suitable for electrical studies and can represent a general model in terms of validity. Finally, the model simulation outputs are compared with experimental measurements during a discharge–charge sequence.
In this paper, the reversible and the irreversible loss in performance of direct methanol fuel cell (DMFC) single cells induced by freeze/thaw cycling are determined and discussed. The reversible loss in performance is attributed to the decreased activity of electrocatalysts due to the strong adsorption of the intermediates from methanol electro-oxidation at subzero temperatures, while the irreversible loss in performance is due to the damage of membrane electrode assembly (MEA) structure. It is found that the reversible degradation of performance is dominant when the cell operated at low current densities with O2; the irreversible degradation is more obvious when the cell discharged at high current densities or operated with air. A method, applying a reverse current on the single cell, is put forward to recover the reversible loss in performance. By this method, the voltage of the single cell operated with O2 at 100 mA cm−2 drops only about 16 mV after experiencing 100 freeze/thaw cycles between−10 and 60 °C.
Solid polymer electrolyte (SPE) films consisting of polyvinyl butyral (PVB) as host polymer, LiClO4 as alkali salt at mole ratio of [O]:[Li]=8, and different molecular weight polyethylene glycol (PEG) including PEG200, PEG400, and PEG600 as plasticizers are prepared by physical blending method. The dielectric relaxation and electrochemical impedance measurements reveal that the conductive performances are improved by adding PEG as plasticizers through the enhancement in the moving space for ions, and PEG400 performs plasticizing effect superior to PEG200 and PEG600. Their conductivity is measured by using a sandwiched Pt/SPE/Pt cell model. SPE with 30% PEG400 (wt%) of PVB exhibits the maximum conductivity at room temperature, and its conductivity increases linearly with temperatures from 303 to 333K at two to three orders of magnitude higher than that of the other two SPEs containing 30% PEG200 and 30% PEG600, respectively. However, their conductivity does not increase linearly with the increase in heating temperatures until the temperature reaches around 333K; the decrease in conductivity with heating from their maxima is attributed to the restriction of ion moving space because of the crosslinking reaction between hydroxyl and aldehyde groups. As observed from the XRD and the microscopy results, PEG400 is more effective than others in enhancing the conductive performances of these SPEs through changing LiClO4 from crystalline to amorphous state, increasing the flexibility of PVB, disturbing the short distance sequential order of PVB chains, and promoting the formation of ‘pathway’ for ions’ movement.
It is generally acknowledged that people blind from birth develop supra-normal sensory abilities in order to compensate for their visual deficit. While extensive research has been done on the somatosensory and auditory modalities of the blind, information about their sense of smell remains scant. The goal of this study was therefore to compare odor perception and odor awareness in a group of 11 congenitally blind and 14 sighted control subjects. We measured odor detection threshold, odor discrimination and odor identification using the Sniffin'Sticks test. Participants also filled in the Odor Awareness Scale (OAS) to assess consciousness of olfactory sensations. Our data showed that blind subjects had a lower odor detection threshold compared to the sighted. However, no group differences were found for odor discrimination and odor identification. Interestingly, the OAS revealed that blind participants scored higher for odor awareness. The largest group differences were found for items of the OAS that measure responses to body odors and fragrances. We conclude that blind subjects rely more on their sense of smell than the sighted in order to assess their environment and to recognize places and other people.
In this paper, the development of a three-dimensional (3D) lithium titanium oxide (LTO) pouch cell is presented to first better comprehend its thermal behavior within electrified vehicle applications, but also to propose a strong modeling base for future thermal management system. Current 3D-thermal models are based on electrochemical reactions which are in need for elaborated meshing effort and long computational time. There lacks a fast electro-thermal model which can capture voltage, current and thermal distribution variation during the whole process. The proposed thermal model is a reduce-effort temperature simulation approach involving a 0D-electrical model accommodating a 3D-thermal model to exclude electrochemical processes. The thermal model is based on heat-transfer theory and its temperature distribution prediction incorporates internal conduction and heat generation effect as well as convection. In addition, experimental tests are conducted to validate the model. Results show that both the heat dissipation rate and surface temperature uniformity data are in agreement with simulation results, which satisfies the application requirements for electrified vehicles. Additionally, a LTO battery pack sizing and modeling is also designed, applied and displays a non-uniformity of the cells under driving operation. Ultimately, the model will serve as a basis for the future development of a thermal strategy for LTO cells that operate in a large temperature range, which is a strong contribution to the existing body of scientific literature.
Electrochemical capacitors are important energy storage devices that have high power density, rapid charging cycles and are highly cyclable. In this study, activated fluid coke has demonstrated high surface area, improved capacitive properties, and high energy density. Fluid coke is a by-product generated from continuous high temperature bitumen upgrading, resulting in the formation of nearly spherical particles with concentric carbon layers. The residual sulphur impurities in fluid coke may enhance its energy storage performance. The activated coke samples have high specific surface areas, up to 1960 m2 g−1, and show promising capacitive performance, in 4 M KOH electrolyte, with high gravimetric and specific capacitances of 228–257 F g−1 and 13–14 μF cm−2, respectively. These results are comparable to other top performing activated carbon materials [1–3]. The activated fluid coke maintains high performance at fast charging rates, greater than 160 F g−1 at a current density of 7500 mA g−1. Activated fluid coke's high capacitance and promising rate performance are potentially associated with its unique layered, and the moderate sulphur content in the chemical structure. Activated fluid coke is a unique opportunity to use a limited use by-product to generate activated carbon that has a high surface area and promising energy storage properties.