batterydata/paper-abstracts huggingface dataset:
Electrical testing of negative limited mono-pocket plate cells, cyclic voltammetry and surface analysis by X-ray diffraction were used to investigate the origin of the second discharge plateau at the cadmium pocket plate electrode. The electrical testing results show that there is a direct coupling between the appearance of a second discharge plateau and a high carbonate concentration in combination with high discharge rates (1 C5A). An exchange to a carbonate free electrolyte results in recovering of the cell. Voltammetric measurements show that the reduction of CdCO3 takes place in the same potential region as the reduction of Cd(OH)2. Thus, the presence of CdCO3 in the discharged negative electrode cannot give rise to a second voltage plateau or capacity loss. However, a decrease in the hydroxide concentration results in a positive shift of the oxidation potential. These results are interpreted in the context of the porous structure of the pocket plate cadmium electrode. For a high carbonate concentration and large discharge rates, the hydroxide concentration within the pores are depleted leading to a positive potential shift and the appearance of a second discharge plateau.
The BONEBRIDGE (MED-EL, Innsbruck, Austria) is a bone-conduction implant used in the treatment of conductive and mixed hearing loss. The BONEBRIDGE consists of an external audio processor and a bone-conduction floating mass transducer that is surgically implanted into the skull in either the transmastoid, retrosigmoid or middle fossa regions. The manufacturer includes self-tapping screws to secure the transducer; however, self-drilling screws have also been used with success. In cases where the skull is not thick enough to house the transducer, lifts are available in a variety of sizes to elevate the transducer away from the skull. The objective of the present study was to investigate the effects of screw type, lift thickness, and implant location on the sound transmission of the BONEBRIDGE.
Molybdenum disulfide (MoS2) exhibits additional reversible capacity beyond their theoretical value is promising candidates for electrodes of lithium ion batteries (LIBs). However, the sluggish kinetics, low conductivity and self-aggregating of MoS2 nanosheets hinder the practical application. Herein, ultra small few layer MoS2 combined with carbon hybrids of macro-micro-mesoporous structure (MoS2/MmC) is prepared via a simple and scalable liquid-solid-gas three-phase interface self-assembly process. When employed as anode for lithium ion batteries, such a clever structure possesses superior performance: exhibits discharge capacity of 938 mAh g−1 at current density of 200 mA g−1 following 100 cycles, and reveals reversible capacity of 843 mAh g−1 at current density of 2 A g−1 after 1000 cycles. The excellent performance is attributed to the rational design of electrode structure: ultra small few layer MoS2 nanosheets offer abundant active sites, while the 3D porous architectures are in favor of enhancing the mass-transportation and alleviating the volume expansion. These structural features greatly enhance surface reaction kinetics and facilitate the charge transport. Furthermore, Ex-situ XRD, FESEM are used to confirm the phase transformation of MoS2/MmC and verify the structure stability during the cycling. It is believed that our work opens up a new possible route for the industrial production of MoS2 based anode materials.
For applications that require power densities greater than 500W/kg, electrochemical capacitors are better suited than batteries because of their high power and long cycle life, but improvement in their energy density is still desired. Creating sophisticated surface morphologies and utilizing faradaic materials have been successful in improving the energy density of electrochemical capacitors. However, to our knowledge, there have been no studies exploring coating carbon material with non-transition metal oxides as a means to improve energy storage of electrochemical capacitors. By utilizing SiO2 nanoparticles coated on a variety of carbon substrates, we can increase the energy density of electrochemical capacitors between 10% and 29% at 500W/kg and between 30% and 85% at 1000W/kg in organic electrolytes. We have also shown that these coatings can increase the capacitance normalized to specific surface area between 39% and 47%.
In this work, silicon–carbon composite particles were designed and synthesized for the anode materials of a lithium ion battery and synthesized using a simple method that is adaptable for industrial application. The silicon/carbon precursor and monomer mixtures were polymerized through solution polymerization in an organic continuous medium and granulated in a polyvinyl alcohol (PVA) aqueous solution. After carbonization of the obtained composite particles, the electrochemical properties were investigated. The enhanced specific capacity (1014.15mAh/g) and cyclability (80% of cycle retention) were attributed to the etching process and the porous structure. The particle morphology was observed by scanning electron microscopy. The surface area and pore volume of the particles were measured by nitrogen adsorption via the Brunauer–Emmett–Teller method.
The superior electrical conductivity and parallel ion pathways formed by aligned carbon nanotubes (A-CNTs) make them attractive for the nanoporous electrodes of supercapacitors. To achieve high volumetric energy and power densities, the low volume density of the as-synthesized A-CNT (<5%) should be densified. In this paper, we demonstrate a mechanical densification method that allows the density of A-CNTs to be tuned precisely over a broad range while preserving the straight ion pathway between A-CNTs. The supercapacitors fabricated from 40% volumetric fraction (Vf) of A-CNTs as the electrodes with the thickness of 0.8mm exhibit a power density of 25kWL−1 (50kWkg−1), which is much higher than that of the A-CNTs electrodes with similar thickness fabricated by other methods and that of activated carbon electrodes.
The purpose of this study was to examine the cognitive and clinical correlates of the MATRICS Consensus Cognitive Battery (MCCB) which was originally developed to be an endpoint for cognitive enhancement clinical trials. In a sample of 117 people with schizophrenia and 77 healthy control participants we found the following: a) the MCCB was highly sensitive to the type and level of impairment typically observed in schizophrenia, b) the MCCB composite score was highly correlated with WASI Estimated Full Scale IQ score, c) that the MCCB domain scores were generally moderately–highly intercorrelated, d) that MCCB performance was minimally related to clinical symptom type and severity, and e) the MCCB is sensitive to employment status with better performance in employed vs. unemployed patients. These data support the validity of the MCCB as a sensitive measure of cognitive impairment in schizophrenia and suggest that MCCB performance is relevant for functional outcome. The data also suggest that the MCCB domain scores may offer limited resolution on discrete cognitive functions.
As part of two USJGOFS cruises, we investigated spatial variability in phytoplankton properties across the strong environmental gradient associated with the Antarctic Polar Frontal Zone during late austral summers of 1997 and 1998. Cell properties, including size and an index of pigment content as well as photosynthetic efficiency (as indicated by relative variable fluorescence), changed dramatically across this frontal region. A general trend toward reduced photosynthetic efficiency south of the Polar Front was correlated with low dissolved iron concentration and is consistent with physiological iron limitation in the phytoplankton. We detected no significant differences in photosynthetic efficiency among different size classes of the dominant pico- to nanophytoplankton, despite a systematic community level shift toward larger sized cells south of the Polar Front. In contrast to other cells, those classified as cryptophyte algae showed relatively high photosynthetic efficiency in low iron waters; however, this group was never found in high abundance. One group, all cells ⩽2μm, showed an unexpected increase in intracellular pigment content (based on single cell chlorophyll fluorescence measurements) south of the Polar Front where dissolved iron concentration and the cells’ relative abundance were low. Overall, these results suggest that group- or size-specific differences in physiological status were not directly regulating community structure in the pico- to nanophytoplankton during the late summer season; other processes, such as differential grazing or sinking losses, must be important.
Ag-MnOx/C composites were prepared using AgNO3 and KMnO4 as the precursors and Vulcan XC-72 as the support. The physical properties of the Ag-MnOx/C composites were investigated via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The activity and the stability of the series of Ag-MnOx/C composites toward the oxygen reduction reaction (ORR) in alkaline media were investigated through the electrochemical techniques. The results show that the main species MnO2 and Ag2O in the fresh sample convert into Mn3O4 and Ag(0), respectively, after the heat treatment in N2 at 300°C (Ag-MnOx/C-300). The Ag-MnOx/C-300 sample shows the highest activity toward the ORR, with the half-wave potential of the ORR shifting negatively only 0.035V compared to that on the commercial 40wt. % Pt/C (JM). The electron transfer number during the ORR on the Ag-MnOx/C composite increases with the value close to four after the heat treatment at 300°C, which is mainly attributed to the formation of Ag(0), rather than Mn3O4. The heat treatment brings about a better catalytic stability of the composite, and no obviously negative shift takes place for the half-wave potential of the ORR on the Ag-MnOx/C-300 composite after 1000 cycles accelerated aging test. The maximum power density of the zinc-air battery with the Ag-MnOx/C-300 air electrode reaches up to 130 mW cm−2, higher than those based on the Pd/C and Pt/C cathode catalysts, which shows that the Ag-MnOx/C-300 composite is a promising candidate as the catalyst for the air electrode.
In this work, an isothermal, physics-based, dual lithium-ion insertion cell sandwich model is used for simulating the galvanostatic charge performance of a graphite (Li x C6)/liquid electrolyte/Li y (Ni a Co b Mn c )O2 at room temperature at various current densities. The modeling results are compared with experimental cell potential vs. capacity data. The validated model is used to identify the bottlenecks to fast charging by quantification of the various contributions to the cell overpotential. Lithium plating at the negative electrode is shown to be thermodynamically feasible during galvanostatic charging at 2C rate and above. This work will aid in research and development activities to overcome the hurdles to fast charging of advance electric vehicle batteries.
Electric vehicles (EVs) represent one of the most promising technologies to green the transportation systems. An important issue is that high penetration of EVs brings heavy electricity demand to the power grid. One effective way to alleviate the impact is to integrate local power generation such as renewable energy sources (RESs) into charging infrastructure. Because of the intermittent and indispatchable nature of RESs, it becomes very challenging to coordinate EVs charging with other grid load and renewable generation. In this paper, EVs charging problem in the presence of smart grid technologies is investigated, and the interaction with renewable energy is reviewed. An overview about EVs and RESs is first presented, which mainly introduces major types of EVs and renewable energy estimation methods. Then, according to the objectives, the existing research works are divided into three categories: cost-aware, efficiency-aware, and emissions-aware interactions between EVs and RESs. Each category׳s discussion includes the description of core ideas, summarization of solutions, and comparison between different works. Finally, some key open issues about EVs interacting with RESs are given and some possible solutions are also discussed.
The electrochemical properties of sulfur cathode with Ni foam current collector are investigated in detail. Different from sulfur cathode with stain steel current collector, it is interesting found that novel redox peaks at 1.95 V/1.35 V are observed for sulfur cathode with Ni foam. The electrochemical behavior is further verified by ex-situ XRD, SEM and XPS analyses. The results indicate that Ni foam current collector is involved in the redox reaction in Li/S rechargeable battery, and NiS forms at the surface of the Ni foam. These results demonstrate that the sulfur electrode is transformed into NiS.
The chemical–physical properties of hydrophobic ionic liquids, tailored as electrolyte components for supercapacitors and lithium batteries, were investigated and compared. The ionic liquid samples are based on bis(perfluroalkylsulfonyl)imide anions coupled with different types of cation. The effect of the cation as well as the main cationic aliphatic side group, in combination with different anions, on the chemical–physical properties of the investigated ionic liquid samples was evaluated and discussed. The activation energy for the conduction mechanism and the glass transition temperature were obtained by fitting the conductivity vs. temperature data.
A new inverse spinel LiNi1/3Co1/3Mn1/3VO4 cathode material was synthesized through a citric acid assisted polyethylene glycol (CA:PEG; 3:1, 3:0.5 and 3:0) polymeric method, followed by calcination at 723K for 5h in air. The synthesized compound was characterized by TG/DTGA, XRD, FTIR, TEM, and 7Li NMR techniques. TG/DTGA curves showed that the formation of LiNi1/3Co1/3Mn1/3VO4 occurred between 523 and 673K and the phase pure crystalline formed at 723K, as also confirmed by XRD analysis which showed that the crystalline phase peaks formed when heated at 723K for 5h in air. TEM images revealed that nanosized particles ranged ∼170–190nm. FTIR spectra showed that all organic residues were removed and LiNi1/3Co1/3Mn1/3VO4 formed. The 7Li MAS NMR spectrum of the LiNi1/3Co1/3Mn1/3VO4 sample revealed that the paramagnetic effect is small and small side band manifolds were observed. The galvanostatic cycling study suggests that the cycle stability and capacity retention were enhanced for LiNi1/3Co1/3Mn1/3VO4 prepared with a CA:PEG molar ratio of 3:1 when it was cycled between 2.8 and 4.9V (versus Li) at a 0.15C rate. The electrochemical impedance behavior suggested that a passive layer was formed on the surface of the cathode materials during continuous cycling.
Sheet-like lithium-rich cathode materials Li1.2Mn0.54Ni0.16Co0.10O2 (LMNCO) assembled by primary grains of 100–500 nm in sizes were facilely prepared by a glucose-urea bubbling and post-annealing process. The post-annealing temperature was found to play an important role on the grain size, crystallinity, cation ordering and electrochemical performance of the cathode materials. The sample post-annealed at 900 °C showed larger grains, higher crystallinity, better layered structure, higher lithium storage capacity and better rate performance than the one annealed at 800 °C. An initial discharge capacity of above 300 mA h g−1 was obtained at 0.1 C (20 mA g−1) for the sample annealed at 900 °C, and at 1, 2, 5 and 10 C, discharge papacies of 223, 192, 157 and 128 mA h g−1 were achieved respectively. The material synthesizing process proposed in this study may be extended to prepare a wide range of sheet-like functional oxides that may be potentially applied in energy storage or other fields.
A novel method was developed to synthesize ordered sandwich-structured magnesiothermo-reduced Si nanoparticles (MR-Si NPs)-thermally reduced graphene oxide (TRGO) nanocomposites that combines magnesiothermic reduction, freeze-drying, and thermal reduction. The MR-Si NPs were dispersed into ordered graphene oxide (GO) layers with the aid of sonication. This MR-Si@TRGO composite structure was retained by freeze-drying and followed by thermal reduction. The key features of the nanocomposites, including nanoparticle crystal phase, size, and dispersity on the TRGO matrix, could be controlled by tuning reaction conditions such as reduction temperature and duration. The influence of the weight ratio of active materials: conductive agent: binder, the types of binder, and the content of electrolytes on the electrochemical performance as an anode in lithium-ion batteries was systematically investigated. The electrode fabricated using the MR-Si@TRGO nanocomposites under optimized conditions (80:10:10 for the weight ratio of MR-Si@TRGO: acetylene black: CMC; the electrolyte containing 5 v% vinylene carbonate) exhibited a reversible capacity of 746mAhg−1 after 160 cycles at 1000mAg−1, which is substantially higher than 701mAhg−1 after 120 cycles for the MR-Si@TRGO in the absence of vinylene carbonate, 330mAh g−1 for commercial graphite reported, and 10mAhg−1 for pure MR-Si NPs tested at 200mAg−1 with a weight ratio of 50:30:20 optimized for active materials: acetylene black: PVDF.
Numerical modelling is the method by virtually testing and verifying the functionality of a specific product or component. The primary goal is to get approximate results of how the system behaves in a given time and environment. This paper deals with a possibility of the use the numerical simulation for system simulation in the unconventional power sources of electrical energy. This method is useful in application where the complex environment is necessary to use, e.g. electro-mobility, solar power station, etc. It is possible to simulate electro-chemical reactions, current fields, temperature fields, electric potentials, concentrations, charging and discharging cycle, electromagnetism, etc. In this case, it will be presented the multiphysical approach of system simulation of short circuit in the lithium ion battery.
This paper proposes a methodology for the economic optimisation of the sizing of Energy Storage Systems (ESSs) whilst enhancing the participation of Wind Power Plants (WPP) in network primary frequency control support. The methodology was designed flexibly, so it can be applied to different energy markets and to include different ESS technologies. The methodology includes the formulation and solving of a Linear Programming (LP) problem. The methodology was applied to the particular case of a 50MW WPP, equipped with a Vanadium Redox Flow battery (VRB) in the UK energy market. Analysis is performed considering real data on the UK regular energy market and the UK frequency response market. Data for wind power generation and energy storage costs are estimated from literature. Results suggest that, under certain assumptions, ESSs can be profitable for the operator of a WPP that is providing frequency response. The ESS provides power reserves such that the WPP can generate close to the maximum energy available. The solution of the optimisation problem establishes that an ESS with a power rating of 5.3MW and energy capacity of about 3MWh would be enough to provide such service whilst maximising the incomes for the WPP operator considering the regular and frequency regulation UK markets.
Aim Attention deficit and compromised motor skills are both prevalent in Neurofibromatosis type 1 (NF1), but the relationship is unclear. We investigated motor function in children with NF1 and in children with Attention Deficit/Hyperactivity Disorder (ADHD), and explored if, in patients with NF1, attention deficit influences motor performance. Methods Motor performance was measured using the Movement Assessment Battery for Children (M-ABC) in 71 children (26 with NF1 plus ADHD, 14 with NF1 without ADHD, and 31 with ADHD without NF1) aged 6–12 years. Results There was a significant effect of group on motor performance. Both NF1 groups scored below children with ADHD without NF1. Attention performance mediated motor performance in children with ADHD without NF1, but not in children with NF1. Conclusions Motor function is not mediated by attention performance in children with NF1. While in ADHD, attention deficit influences motor performance, motor problems in NF1 seem to be independent from attention deficit. This argues for different pathomechanisms in these two groups of developmental disorders.
Ti/Si/Ti sandwich-like thin film, which has been fabricated on copper foam by magnetron sputtering, has been studied as anode material for rechargeable lithium-ion batteries. Instrumental analyses of Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) have been employed to characterize the structure, morphology, composition and valence of the as-deposited films. Charge/discharge tests, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) have been performed to investigate the electrochemical performance of Ti/Si/Ti thin film. It is found that Ti/Si/Ti thin film delivered an initial discharge capacity of 2656 mAh g−1 and a reversible capacity of 1071 mAh g−1 after 100 cycles at 0.5C. When the discharge rate is increased to 10C, the discharge capacity is 950 mAh g−1. The enhanced electrochemical performance is mainly attributed to Ti/Si/Ti sandwich-like structure, which benefits the electrode stability and the electrode process kinetics. The results indicate that the sandwich-like structure is promising in the development of Si-based anode for rechargeable lithium-ion batteries.
Ethnopharmacological relevance Medicinal plants are known to contain numerous biologically active compounds, and although they have proven pharmacological properties, they can cause harm, including DNA damage. Aim of the study Review the literature to evaluate the genotoxicity risk of medicinal plants, explore the genotoxicity assays most used and compare these to the current legal requirements. Material and methods A quantitative systematic review of the literature, using the keywords “medicinal plants”, “genotoxicity” and “mutagenicity”, was undertakenQ to identify the types of assays most used to assess genotoxicity, and to evaluate the genotoxicity potential of medicinal plant extracts. Results The database searches retrieved 2289 records, 458 of which met the inclusion criteria. Evaluation of the selected articles showed a total of 24 different assays used for an assessment of medicinal plant extract genotoxicity. More than a quarter of those studies (28.4%) reported positive results for genotoxicity. Conclusions This review demonstrates that a range of genotoxicity assay methods are used to evaluate the genotoxicity potential of medicinal plant extracts. The most used methods are those recommended by regulatory agencies. However, based on the current findings, in order to conduct a thorough study concerning the possible genotoxic effects of a medicinal plant, we indicate that it is important always to include bacterial and mammalian tests, with at least one in vivo assay. Also, these tests should be capable of detecting outcomes that include mutation induction, clastogenic and aneugenic effects, and structural chromosome abnormalities. In addition, the considerable rate of positive results detected in this analysis further supports the relevance of assessing the genotoxicity potential of medicinal plants.