batterydata/paper-abstracts huggingface dataset:
In this study, the linguistic performance of 20 patients with acute conduction aphasia (CA) is described. CA presented as a relatively homogeneous aphasic syndrome characterized by a severe impairment of repetition and fluent expressive language functions with frequent phonemic paraphasias, repetitive self-corrections, word-finding difficulties, and paraphrasing. Language comprehension as assessed by tests of auditory and reading comprehension was only mildly impaired, whereas most patients performed poorly on the Token Test. Verbal-auditory short-term memory was reduced in all patients except one and seems to play a role in associated cognitive deficits, such as impaired syntactic comprehension or reduced mental arithmetics. A follow-up examination of 12 patients showed that CA often resulted in a chronic language deficit. Lesion locations were the posterior temporal and inferior parietal lobe.
Many researchers and industry observers claim that electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) could provide vehicle-to-grid (V2G) bulk energy and ancillary services to an electricity network. This work quantified the impact on various battery characteristics whilst providing such services. The sensitivity of the impact of V2G services on battery degradation was assessed for EV and PHEV for different battery capacities, charging regimes, and battery depth of discharge. Battery degradation was found to be most dependent on energy throughput for both the EV and PHEV powertrains, but was most sensitive to charging regime (for EVs) and battery capacity (for PHEVs). When providing ancillary services, battery degradation in both powertrains was most sensitive to individual vehicle battery depth of discharge. Degradation arising from both bulk energy and ancillary services could be minimised by reducing the battery capacity of the vehicle, restricting the number of hours connected and reducing the depth of discharge of each vehicle for ancillary services. Regardless, best case minimum impacts of providing V2G services are severe such as to require multiple battery pack replacements over the vehicle lifetime.
Carbon-based electrodes are usually used in vanadium redox flow batteries and electrochemical performance of these electrodes can be modified by electrocatalysts. In the current study, reduced graphene oxide inks with different concentrations were used to modify a carbon felt electrode. It was observed that CF which was modified in 2 mg/ml ink (CF-G-2) had the optimum combination of electrochemical properties, because no significant peak current improvement was observed at higher graphene contents and it also had the minimum value of ΔEp. The anodic and cathodic peak currents for positive redox couple reaction in CF-G-2 reached to 45.3 and 21.1 mA respectively, in comparison with 14.2 and 4.7 mA values for bare felt. Linear diffusion coefficient was also enhanced more than two times with the incorporation of graphene. Nyquist plots of CF-G in different electrolytes (VOSO4/V2O5 and VOSO4) showed different shapes and equivalent circuit data indicated much lower charge transfer resistance for modified carbon felts with graphene. The diffusion process was remarkably facilitated with the incorporation of reduced graphene oxide and graphene had desirable influence on the electrolyte absorption of carbon felt. Finally, scanning electron micrographs of electrodes demonstrated loaded graphene nanosheets on the surface of carbon felt fibers.
Previous studies of magnetic resonance imaging (MRI) as a diagnostic tool for central nervous system (CNS) syndromes in systemic lupus erythematosus (SLE) contained several limitations such as study design, number of enrolled patients, and definition of CNS syndromes. We overcame these problems and statistically evaluated the diagnostic values of abnormal MRI signals and their chronological changes in CNS syndromes of SLE.
Single crystalline tellurium (Te) nanotubes grown on carbon fiber cloth (Te/CFC) conductive substrates have been prepared by a chemical vapor deposition (CVD), which are used as the cathode for flexible all-solid-state lithium-tellurium (Li-Te) rechargeable batteries with high safety. To refrain from the dissolution of Te nanotubes in carbonate electrolytic solution and enhance the long-term security of Li-Te batteries, we directly assemble Te/CFC cathode, polymer solid electrolyte and Li metal anode into flexible all-solid-state Li-Te batteries with the sandwich structure, without using any ancillary materials. The solvent-free feature and high conductivity of Te nanotubes grown on carbon substrate endow the excellent electrochemical performance and long-term security of Li-Te batteries. A high gravimetric capacity of 316 mA h g−1 and a volumetric capacity of 1979 mA h cm−3 after 500 cycles at a current density of 100 mA g−1 can be obtained, respectively. It also exhibits excellent rate capabilities for Li-Te batteries, which is attributed to the synergetic effect from integrated structure of electrodes and solvent-free solid-state electrolyte. These results demonstrate that flexible all-solid-state Li-Te rechargeable batteries based on Te/CFC cathode show promising applications in safe energy storage and portable electronic devices.
The present study synthesized Mo-doped δ-MnO2 powders with different doping ratios by implementing hydrothermal method. Various analyses, namely X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), the Brunauer–Emmett–Teller (BET) method, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray fluorescence spectrometer (XRF), and electrochemical measurements, were applied to characterize the dependence of the δ-MnO2 structure, morphology and electrochemical performance on Mo-doping. The experimental results indicated Mo6+ ions entered into the δ-MnO2 crystal lattice and occupied the Mn sites. Appropriate amount of Mo6+ ions doping decreases the charge transfer resistance and increases the Li+ ion diffusion coefficient, thus producing optimal electrochemical performance. The Mo 5% sample with Mo6+/Mn2+ molar ratio of 5:100 in the original solution presented a specific charge capacity of 476.8 mAh g−1 after 100 cycles at 1000 mA g−1 as well as capacity retention ratio of 112.7%.
This paper discusses the effects of a colloidal phase on the ionic conductivity and transport mechanism in liquid and polymer electrolytes. The conductivity enhancement due to the addition of diverse ceramic colloids is attributed to the formation and existence of double layers. These colloids and associated double layers also lead to time-dependent conductivity variation in a certain temperature range. Annealing and physical aging effects on conductivity originate from the existence and displacement of the double layer surrounding each colloidal particle. It has also been suggested that one can design and develop electrolytes for specific applications by selecting three critical elements: a conducting ion, a transport medium, and a network of double layers in a colloidal or composite electrolyte.
Lithium-ion batteries (LIBs) have been employed in many fields including cell phones, laptop computers, electric vehicles (EVs) and stationary energy storage wells due to their high energy density and pronounced recharge ability. However, energy and power capabilities of LIBs decrease sharply at low operation temperatures. In particular, the charge process becomes extremely sluggish at temperatures below −20 °C, which severely limits the applications of LIBs in some cold areas during winter. Extensive research has shown that the electrolyte/electrode composition and microstructure are of fundamental importance to low-temperature performances of LIBs. In this report, we review the recent findings in the role of electrolytes, anodes, and cathodes in the low temperature performances of LIBs. Our overview aims to understand comprehensively the fundamental origin of low-temperature performances of LIBs from a materials perspective and facilitates the development of high-performance lithium-ion battery materials that are operational at a large range of working temperatures.
Porous carbon nanofibers are synthesized by CVD method from acetylene with use of iron-containing catalysts. Activation of the nanofibers in melted potassium hydroxide results in increasing surface area from initial 300–400m2 g−1 to 1700m2 g−1. As follows from XRD data, activated nanofibers do not contain regular packages of graphene layers, but retain high electric conductivity. Deposition of copper improves electrochemical hydrogen storing characteristics of carbon nanofibers. Carbon nanomaterials obtained can be used as hydrogen storing materials in batteries instead of hydride forming metals.
Tin oxide (SnO) was coated on the surface of aluminum spherules with an average particle size of 37μm by a chemical deposition method to improve the electrochemical properties. The samples were characterized by particle size analysis, X-ray diffraction (XRD), scanning electron microscope (SEM), ac impedance spectroscopy and galvanostatic cycling. Pure aluminum electrode delivers an initial reversible capacity of 779mAhg−1, whose capacity loss is 58% after 10 cycles. In comparison, 10wt% SnO–Al composite delivers an initial reversible capacity of 806mAhg−1 with the capacity loss of 28% after 10 cycles. Results show that SnO coating plays an important role in the improvement of the electrochemical performances. It could not only reinforce the mechanical stability of aluminum particles, but also provide better electronic contacts to the electrode.
The influence of sintering temperature on the polarization resistance of screen printed La2NiO4+δ (LNO) cathodes is studied. The electrode dispersion is measured on symmetrical cells with a 100 μm 3% yttria-doped zirconia (TZ3Y) electrolyte and screen-printed yttria-doped ceria (YDC) barrier layers. The as-received commercial LNO powder was used in the formulation of the ink. For cathodes prepared following this procedure the optimum sintering temperature is 1000 °C. Analysis of the impedance spectra shows clearly a Gerischer dispersion (chemical impedance), with an activation energy of 124 kJ mol−1 for the exchange rate parameter K G . The addition of a dense LNO layer between electrolyte and porous electrode lowers the ASR by ∼35%, showing a significant change in the oxygen transfer mechanism. A tentative model, based on a global two step oxygen exchange mechanism, is presented. There are also strong indications that surface diffusion of mono atomic oxygen is a major transport path. The electronic conductivity of LNO is too low at the intended operating temperature of ∼600 °C, resulting in an additional resistance to the apparent electrolyte resistance.
Nitrogen-doped graphene (NG) has been fabricated and used as a carbon matrix for sulfur impregnation to construct cathodes for lithium–sulfur (Li–S) batteries. Atomic layers of TiO2 were further deposited on the electrode and the thickness was controlled by adjusting the number of deposition cycles to 0, 5, 20 and 40. The results showed that all the surface modified electrodes demonstrate high capacity, good rate capability, and enhanced cyclability compared to the bare electrode. Specifically, the electrode contained 59% (by weight, wt%) sulfur and with the addition of 20 cycle-TiO2 it demonstrated a superior boost in the active sulfur utilization (discharge capacity: 1374 mA h g−1 at 0.1C). It also delivered initial discharge capacity up to 1069.5 mA h g−1 and 918.3 mA h g−1 after 500 cycles at 1C with an average coulombic efficiency of about 99.7%. Moreover, the capacity retention increased from 42% to 61% from 0.1C to 4C with the addition of 20 cycle-TiO2. The improved electrochemical performance could be attributed to the on-site TiO2 absorption for polysulfide retention as well as the charge transfer enhancement. Theoretical calculations revealed that TiO2 exhibits a strong binding energy for lithium polysulfide species. These results suggest that the TiO2 modified NG has potential to be used as a cathode for high-performance Li–S batteries.
Designing a bifunctional air electrode which catalyses both the oxygen reduction and oxygen evolution reactions is an essential part of progress towards fully rechargeable metal-air batteries, such as the iron-air battery which is environmentally friendly, low cost, and does not suffer risk of thermal runaway like lithium-ion batteries. This paper reports the development of a lightweight carbon-based bifunctional air electrode, catalysed by a small (0.5mgcm−2) loading of 30wt.% palladium on carbon. The Pd-catalysed air electrode showed good bifunctional activity, with 0.53V potential difference between oxygen reduction and evolution. The Pd/C air electrode showed improved catalytic activity at high current densities (≥ 50mAcm−2) and enhanced durability compared with two commercial Pt/C air electrodes produced by Gaskatel GmbH and Johnson Matthey. A stable oxygen evolution potential was maintained over 1,000 charge-discharge cycles.
The main movement disorders in cerebral palsy (CP) are spasticity, dystonia, athetosis and chorea. Their neurosurgical treatments have improved dramatically in the past two decades. Focal spasticity can now be effectively treated with peripheral selective neurectomies, spastic diplegia with lumbar dorsal rhizotomies, and generalized spasticity with continuous intrathecal baclofen (ITB) infusion. Dystonic CP is usually generalized and can be treated with ITB; refractory cases may respond to deep brain stimulation. There are presently no effective neurosurgical options for athetosis, although deep brain stimulation shows promise for choreiform CP.
The positive effects of incorporating electrically conductive poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT-PSS) into the negative electrode (NE) of a lithium ion capacitor (LIC) is investigated. The binding material of the NE, styrene-butadiene rubber (SBR), is partially substituted by conductive PEDOT-PSS. The soft carbon NE with 1.0 wt% PEDOT-PSS exhibits enhanced capacity retention of 64% at a current density of 5 C by lowering its electrical and electrochemical charge transfer resistance. The rate capability increased with increasing amounts of PEDOT-PSS, with no variation in the Li+ diffusivity. This improved electrochemical performance of the NE is also reflected in the LIC full-cell configuration. An LIC employing a 1.0 wt% PEDOT-PSS NE delivers 6.6 F at a high current density of 100 C, which is higher than the 6.0 F measured for the LIC with a bare NE. Moreover, the LIC with the 1.0 wt% PEDOT-PSS NE retains 85% of its initial capacitance even after 5000 cycles. These results are mainly attributed to the favourable electrical network formed by the incorporation of PEDOT-PSS into the NE. Thus, we believe that the incorporation of conductive PEDOT-PSS is a viable approach for obtaining high-power LICs.
Existing studies on wireless sensor networks (WSNs) have revealed that the limited battery capacity of sensor nodes (SNs) hinders their perpetual operation. Recent findings in the domain of wireless energy transfer (WET) have attracted a lot of attention of academia and industry to cater the lack of energy in the WSNs. The main idea of WET is to restore the energy of SNs using one or more wireless mobile chargers (MCs), which leads to a new paradigm of wireless rechargeable sensor networks (WRSNs). The determination of an optimal order of charging the SNs (i.e., charging schedule) in an on-demand WRSN is a well-known NP-hard problem. Moreover, care must be taken while designing the charging schedule of an MC as requesting SNs introduce both spatial and temporal constraints. In this paper, we first present a Linear Programming (LP) formulation for the problem of scheduling an MC and then propose an efficient solution based on gravitational search algorithm (GSA). Our method is presented with a novel agent representation scheme and an efficient fitness function. We perform extensive simulations on the proposed scheme to demonstrate its effectiveness over two state-of-the-art algorithms, namely first come first serve (FCFS) and nearest job next with preemption (NJNP). The simulation results reveal that the proposed scheme outperforms both the existing algorithms in terms of charging latency. The virtue of our scheme is also proved by the well-known statistical test, analysis of variance (ANOVA), followed by post hoc analysis.
Three-dimensional porous NiO is prepared on Ni foam by a thermal treatment method at various temperatures. The morphology and structure of porous NiO are characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The electrochemical properties of three-dimensional porous NiO anode are evaluated by galvanostatic discharge–charge cycling, cyclic voltammery, and impedance spectral measurements on cells with lithium as the counter and reference electrodes. Results show that porous NiO delivers a stable capacity of 520±20mAhg−1 with no noticeable capacity fading up to 30 cycles when cycled in the voltage range 0.05–3.0V at rate of 0.2C. The porous NiO exhibits higher reversible capacity, better cycleability, as well as higher rate capability in comparison to NiO foil. The observed cyclic voltammograms and impedance spectra are analyzed and interpret a redox reaction of NiO–Ni0 with formation and decomposition of Li2O. The excellent electrochemical performance of porous NiO can be attributed to its large surface area, which lowers the current density of NiO reaction interface, and then an alternative anode is provided for lithium-ion batteries.
Patients presenting with metastatic rhabdomyosarcoma (RMS), the most common soft-tissue sarcoma in children, have a very poor clinical prognosis. This is due, in large part, to our rudimentary knowledge of the molecular events that dictate metastatic potential. We used cDNA microarray analysis of RMS cell lines, derived from Ink4a/Arf-deficient mice transgenic for hepatocyte growth factor/scatter factor (HGF/SF), to identify a set of genes whose expression was significantly different between highly and poorly metastatic cells. Subsequent in vivo functional studies revealed that the actin filament–plasma membrane linker ezrin (encoded by Vil2) and the homeodomain-containing transcription factor Six-1 (sine oculis–related homeobox-1 homolog) had essential roles in determining the metastatic fate of RMS cells. VIL2 and SIX1 expression was enhanced in human RMS tissue, significantly correlating with clinical stage. The identification of ezrin and Six-1 as critical regulators of metastasis in RMS provides new mechanistic and therapeutic insights into this pediatric cancer.
Ternary layered oxides dominate the current automobile batteries but suffer from material scarcity and operational safety. Here the authors report that, when operating at around 60 °C, a low-cost lithium iron phosphate-based battery exhibits ultra-safe, fast rechargeable and long-lasting properties.
Within the context of expansive technological development, the wealth of European society is growing steadily. This has resulted in producing more and more waste. Every year people in the European Union throw away about 3 billion tons of waste. Therefore, the EU must give due attention to this problem. This contribution was created within the Leonardo da Vinci international project Wastre for which the Faculty of Mechanical Engineering is a coordinator. The aim of the contribution is to present a current situation of waste legislation system and waste management of the EU and Slovak Republic. There is also discussed the waste recovery in Slovak Republic with stated examples of best practises in waste recovery.
The performance of a unitised bidirectional vanadium/air redox flow battery (VARFB) is described. It contains a two-layered cathode consisting of a gas diffusion electrode (GDE) with Pt/C catalyst for discharging and of an IrO2 modified graphite felt for charging. A simple routine is shown for the modification of a graphite felt with IrO2. A maximum energy efficiency of 41.7% at a current density of 20 mA cm−2 as well as an average discharge power density of 34.6 mW cm−2 at 40 mA cm−2 were obtained for VARFB operation at room temperature with the novel cathode setup. A dynamic hydrogen electrode was used to monitor half cell potentials during operation allowing to quantify the contribution of the cathode to the overall performance of the VARFB. Four consecutive cycles revealed that crossover of vanadium ions took place and irreversible degradation processes within the reaction unit lead to a performance decrease.
An innovative design strategy for the structural and chemical synergistic encapsulation of polysulfides is proposed. Manganese dioxide nanosheet decorated hollow sulfur sphere nanocomposites are developed through a facile synthesis exhibiting ultralong cycling stability over 1500 cycles and high capacity for high-performance lithium–sulfur batteries.
The structural changes of LiFePO4 and C-coated LiFePO4 during charging at various C-rates and temperatures are investigated using synchrotron based in situ X-ray diffraction technique. The XRD patterns collected during cycling show the structural evidence of the positive effects of carbon coating on LiFePO4 for the electrochemical performance improvements at different temperatures, especially at low temperatures. At −10°C, the C-coated LiFePO4 shows comparable capacities with the sample cycled at room temperature when cycled at C/5 rate with a slight shift of the plateau to a higher voltage during charging. The in situ XRD patterns collected simultaneously show a complete phase transformation from triphylite to heterosite. At −20°C, the C-coated LiFePO4 delivers 55.6% of its theoretical capacities at C/5 rate. However, the plateau in the charging curve becomes sloppy and shifts to a higher voltage. The in situ XRD patterns show that the phase transformation from triphylite to heterosite is not completed when charged to 4.5V due to the larger polarization when charged at −20°C.
A new ionic liquid gel polymer electrolyte based on hydrophobic ionic liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl) trifluorophosphate (EMImFAP) entrapped in poly (vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) copolymer has been prepared for its application as an electrolyte in supercapacitor fabrication. The gel electrolyte film shows excellent thermal stability and remains stable in the same gel phase over a substantially wide temperature range from 5 to 90°C. The gel material possesses wider electrochemical window of ∼4.4V (−2.2 to 2.2V) and high ionic conductivity of ∼2×10−3 Scm−1 at room temperature. The solid-state supercapacitors have been fabricated with pristine and nitric acid treated MWCNT electrodes using the new ionic liquid gel polymer electrolyte. The performance characteristics of the capacitors have been evaluated by impedance spectroscopy, cyclic voltammetry, and galvanostatic charge–discharge measurements. A substantial improvement in the specific capacitance has been found due to the acid treatment of the MWCNTs. The modified MWCNT electrodes show the maximum capacitance value of ∼76Fg−1, which corresponded to the specific energy of ∼17.2Whkg−1 and specific power of ∼18.9kWkg−1 of MWCNT with ionic liquid gel polymer electrolyte based supercapacitor cells. The supercapacitor shows good cycling performance with ∼82% capacitance retention after 10,000 charge–discharge cycles.