batterydata/paper-abstracts huggingface dataset:
Single phase nanobelt-like Na1.2V3O8 was synthesized by precipitation from aqueous solution of V2O5, H2O2 and NaOH, and subsequent annealing at 400 oC. The product was characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. As measured by both galvanostatic charging/discharging and cyclic voltammetry methods, in air-equilibrated aqueous electrolyte solutions containing nitrates of lithium, sodium and magnesium, this compound displayed fast intercalation/deintercalation reactions. The galvanostatic charging and discharging curves observed at rates ranging 500-7000mA g-1, did not display clear plateaus characteristic of phase changes. The discharging capacities were found to range 101-35, 55-17 and 67-22 mAh g-1 for Li, Na and Mg intercalation, respectively. By cyclic voltammetry, for the sweep rates increasing in the range 5-400mV s-1 (roughly 9-700C), the capacity was found to decrease within the limits 63-35 mAh g-1 for Li+ intercalation, and 40 -11 mAh g-1 for Na+ and Mg2+ intercalation, respectively. By analyzing the dependence log (current) versus log (sweep rate), the interval of potentials corresponding to preferably diffusion control of intercalation/deintercalation processes was determined.
Eddy current separation (ECS) is an environment-friendly technology for separating nonferrous metallic particles whose size was from 2 mm to 10 mm. No wastes are generated in ECS. ECS quality of nonferrous metals from solid wastes is rather low in the production practice of spent lithium iron phosphate (LFP) batteries recovering. Repeating separation even manual sorting is required in the production. The traditional method of falling point prediction based on eddy current mechanics uses equivalent acceleration to replace separation motion curves. These curves have low precision and are unsuitable for predicting the motion trajectory of small particle size of sorted materials. In this work, eddy current separation of positive and negative plates in a crushed product of spent lithium iron phosphate battery is used as an example to establish the force and kinematics models of different materials in the eddy current separation. An iterative method, rather than average speed method, is used to improve the accuracy of the model. Displacement interval replaces disengagement angle as a separating index to improve the model’s intuitiveness and practical guidance. In the range of 2–20 mm, test results are consistent with simulation results. The copper and aluminium foils at a magnetic roller speed of 800r/min can be separated to a maximum particle size ratio of 1.72, and the maximum particle size ratio of copper and positive electrode sheets can be large. This paper provided an environmental-friendly and effective technology for separating nonferrous metals from crushed spent LFP batteries.
In this work, we describe a novel approach to the fabrication of MnO2, consisting in Mn electrodeposition from a choline chloride/urea eutectic ionic liquid bath followed by controlled electrochemical oxidation in an aqueous solution. Both electrodeposition and electro-oxidation processes have been studied by electrochemical and in situ spectroelectrochemical approaches. Synchrotron-based soft X-ray scanning microscopy and absorption spectroscopy were used to measure in situ the Mn valence distribution on the electrodes and within the cell. The oxidation process was followed in situ by visible reflectivity measurements: the different stages of the oxidation process could be discriminated dynamically on the basis of relative reflectivity changes. The capacitance of the electrochemically fabricated films has been measured with cyclic voltammetry and electrochemical impedance spectrometry.
This study examined the effect of hypopnoea criteria on the prevalence of positional obstructive sleep apnoea (pOSA) identified under the Amsterdam Positional OSA Classification (APOC) system.
Visual search tasks have standardly been divided into two categories: those in which the target is detected through a serial, attention-driven search and those in which the target is detected rapidly in parallel and, apparently, without attentional processing. Several studies have examined this distinction in patients with hemispatial neglect with the clear prediction that the former, but not the latter, should be impaired. These studies, however, have proved inconclusive. We have addressed this issue in a large sample of patients with unilateral hemispheric infarcts to the left or right hemisphere. In addition to measuring the patients' performance on both types of visual search tasks, we documented the presence and severity of neglect and of visual field defects in these same individuals. Patients with brain-damage with or without accompanying neglect were impaired at searching for the contralateral target on both forms of visual search, relative to normal control subjects, although this deficit was magnified in individuals with neglect and was also exacerbated by the presence of hemianopia. This pattern was also more pronounced in individuals with right- than with left-hemisphere lesions. The findings not only clarify the contradictory neuropsychological data but also provide clear evidence for the involvement of attentional processing in all forms of visual search.
Interest in alternative energy resources such as wind, solar energy and fuel cell (FC) has been on the increase due to improved public awareness of the high energy cost and adverse environmental impacts of conventional energy sources. Therefore, the rapid growth and potential future demand for these energy sources suggest a need to consider both reliability and cost–benefits of the supply for each case. This paper presents a simulation methodology for reliability and cost assessment of these energy sources in an independent micro-grid (IMG) system, which is a distribution system with distributed energy sources such as micro-turbine, photovoltaic and fuel cells. A systematic technique and a computer program for reliability and cost assessment of the IMG system containing FC, photovoltaic (PV) and wind energy (WE) have been developed. The adequacy of the IMG is evaluated in three steps: (i) atmospheric data is generated for PV and WE in addition to the development of a 50kW PEM FC generation and energy conversion model, (ii) the power delivered by these energy sources is calculated, and (iii) system adequacy and energy indices are calculated based on the system load balance equation, which is the combination of generated power and system load demand. The suggested technique can then be used to help system planners to provide objective indicators for suitable installation locations, operating policies, and energy type and size selection for IMG system containing alternative energy sources.
Samples have been prepared with nominal composition Li x (Ni y Co1−y )O2 (x≈1.25, y=0.7–1.0) with the structures being examined using Rietveld analysis of X-ray diffraction data. Rietveld analysis shows that the samples prepared with y=0.70 and 0.75 have no Ni present on the 3a Li site, with all other samples showing a small degree of nonstoichiometry. Structural analysis of the 3b Ni+Co occupancy also suggests the possibility of 3b site disorder, which is in agreement with the results of previous studies. Charge/discharge measurements show an increase in discharge capacity with increasing Ni content, which suggests cobalt plays a very small part in the electrochemical capacities of these phases using the current voltage limits. Samples with y=0.75, 0.8 and 0.85 were found to have very high efficiencies over a number of cycles, typically >99% over 15cycles. Samples prepared with y=0.85 and 0.90 show evidence of a phase change which resembles that seen for LiNiO2. This would suggest that the stabilizing effects of Co in Li x (Ni y Co1−y )O2 is lost when y≥0.85. Therefore, these particular compositions are probably not suitable for use in Li ion cells.
There has been a dramatic rise in the abuse of synthetic cathinones known as “bath salts,” including 3,4-methylenedioxypyrovalerone (MDPV), an analog linked to many adverse events. MDPV differs from other synthetic cathinones because it contains a pyrrolidine ring which gives the drug potent actions as an uptake blocker at dopamine and norepinephrine transporters. While MDPV is now illegal, a wave of “second generation” pyrrolidinophenones has appeared on the market, with α-pyrrolidinovalerophenone (α-PVP) being most popular. Here, we sought to compare the in vitro and in vivo pharmacological effects of MDPV and its congeners: α-PVP, α-pyrrolidinobutiophenone (α-PBP), and α-pyrrolidinopropiophenone (α-PPP). We examined effects of test drugs in transporter uptake and release assays using rat brain synaptosomes, then assessed behavioral stimulant effects in mice. We found that α-PVP is a potent uptake blocker at dopamine and norepinephrine transporters, similar to MDPV. α-PBP and α-PPP are also catecholamine transporter blockers but display reduced potency. All of the test drugs are locomotor stimulants, and the rank order of in vivo potency parallels dopamine transporter activity, with MDPV > α-PVP > α-PBP > α-PPP. Motor activation produced by all drugs is reversed by the dopamine receptor antagonist SCH23390. Furthermore, results of a functional observational battery show that all test drugs produce typical stimulant effects at lower doses and some drugs produce bizarre behaviors at higher doses. Taken together, our findings represent the first evidence that second generation analogs of MDPV are catecholamine-selective uptake blockers which may pose risk for addiction and adverse effects in human users. This article is part of the Special Issue entitled ‘CNS Stimulants’.
The interest on DC micro-grid has increased extensively for the more efficient connection with DC output type sources such as photovoltaic (PV) systems, fuel cells (FC) and battery energy storage systems (BESS). Furthermore, if loads in the system are supplied with DC power, the conversion losses from sources to loads are reduced compared with AC micro-grid. This paper proposes operation and control strategies for the integration of PV and BESS in a DC micro-grid. The proposed control enables the maximum renewable energy utilization during different operating modes of the micro-grid i.e., grid connected, islanded or transition between these two modes, whilst making an allowance for the DC voltage control and DC-loads supply. When the system is grid connected and during normal operation, active power is balanced by the AC grid converter to ensure a constant DC voltage. In order to achieve the system operation under islanding conditions, a coordinated strategy for the BESS, PV and load management including load shedding and considering battery state of charge (SoC), are proposed. Seamless transition of the PV converter control between maximum power point tracking (MPPT) and voltage control modes, of the battery converter between charging and discharging and that of grid side converter between rectification and inversion are ensured for different grid operation modes by the proposed control methods. The DC bus voltage level is employed as an information carrier to distinguish different modes and determine mode switching. MATLAB/SIMULINK simulations are presented to demonstrate the robust operation performance and to validate the proposed control system during various operating conditions.
Highly regulated peanut-like Fe3O4@N-rich carbon (Fe3O4@CN) core-shell microspheres were prepared using a solvothermal method, combined with a facile surfactant (sodium dodecyl sulfate) directed chemical polymerization and subsequent thermal treatment process. As anode electrode materials for Li-ion batteries, the as-prepared Fe3O4@CN composites exhibit higher specific capacity and better cyclic stability than bare Fe3O4. The reversible specific capacity of Fe3O4@CN composite is 670 mAh g−1 in the voltage range of 0.01-3.0V after 30 cycles with no noticeable fading compared with bare Fe3O4(100 mAh g−1). The enhanced electrochemical performance of the composites can be attributed to peanut-like Fe3O4@CN core-shell structure in which monodisperse Fe3O4 particles are entirely coated in the controllable and uniform carbon shell, and the surface contact among carbon shells further improves electronic conductivity due to slight agglomeration of composites after thermal treatment. Moreover, the residual nitrogen in the carbon crystal lattice resulted from the carbonization of polypyrrole enhances the electronic conductivity and brings active defects for the diffusion of lithium ion.
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. We are able to accept a certain numerical error from a real experiment, thus significantly speeding up part of the development of the device. In the field of electrochemistry of lithium-ion accumulators, several variants of numerical models have been proposed that yield satisfactory results in modelling certain physical fields of these batteries (electric field, temperature field, current field).
The Long Island Power Authority's 2002 operating budget includes clean energy initiative expenses for 2002 of $37 million, a 16% increase over the 2001 level of $32 million.
Fast depleting fossil fuels and the growing awareness for environmental protection have led us to the energy crisis. Hence, efforts are being made by researchers to investigate new ways to extract energy from renewable sources. ‘Microgrids’ with Distributed Generators (DG) are being implemented with renewable energy systems. Optimization methods justify the cost of investment of a microgrid by enabling economic and reliable utilization of the resources. This paper strives to bring to light the concept of Hybrid Renewable Energy Systems (HRES) and state of art application of optimization tools and techniques to microgrids, integrating renewable energies. With an extensive literature survey on HRES, a framework of diverse objectives has been outlined for which optimization approaches were applied to empower the microgrid. A review of modelling and applications of renewable energy generation and storage sources is also presented.
One-dimensional nano-structured materials have attracted attention due to its unique properties afforded such as the across-linked structures and large aspect ratios. In this work, one-dimensional CoSe@N-doped carbon nanofibers (CoSe@NC NFs) are successfully by combining the techniques of electrospinning and annealing. Selenium powder are directly dispersed in the polyacrylonitrile /N,N-Dimethylformamide (DMF) solution containing cobalt salt to form the product. The performance of these materials was investigated in Li-ion batteries after the annealing at different temperatures. The CoSe@NC nanofibers annealed at 550 °C (CoSe@NC-550) and displayed excellent storage properties, affording a high capacity of 796 mAh·g−1 at a current density of 1 A·g−1 for 100 cycles. Moreover, it is confirmed that the pseudocapacitive contribution of CoSe@NC-550 is up to 72.8% at the scan rate of 1 mV/s through the cyclic voltammetry analysis.
Chunsheng Wang and colleagues develop an electrolyte strategy to enable the use of commercially available microsized alloys, such as Si–Li, as high-performance battery anodes. They ascribe its success to the formation of robust LiF-rich layers as the solid–electrolyte interface.
Nanosized double substituted LiNi Y Co1−2Y Mn1+Y O4 (Y =0.05, 0.1, 0.25 and 0.45) spinels have been synthesized by a single-step combustion-aided procedure, which use sucrose as fuel. The as prepared samples contained some amorphous organic impurities that were removed after a short heating at 400°C. The samples have been characterized by X-ray diffraction, thermal analysis and transmission electron microscopy. Lattice parameter of the spinels increased with nickel content, and decreased from 400 to 600°C, at which temperature stoichiometric spinels with particle size of ≈20nm were obtained. The electrochemical properties of the 600°C-treated samples in the 5V region have been studied. The sample with composition LiNi0.45Co0.1Mn1.45O4 has shown the best electrochemical performance, with redox potential of 4.6V, capacity of 129.6mAhg−1, cyclability of 99.6% per cycle, and retained the capacity up to 1C rate.
During the preschool years, children develop abilities and skills in areas crucial for later success in life. These abilities include language, executive functions, attention, and socioemotional skills. The pedagogical methods used in preschools hold the potential to enhance these abilities, but our knowledge of which pedagogical practices aid which abilities, and for which children, is limited. The aim of this paper is to describe an intervention study designed to evaluate and compare two pedagogical methodologies in terms of their effect on the above-mentioned skills in Swedish preschool children.
The aims of this study were to compare 2-year cumulative survival rates of amalgam and atraumatic restorative treatment (ART) restorations in primary molars and to investigate the determinants of the survival rate of restorations.
Organic-inorganic halide perovskite solar cells (PSCs) have become a new favorite in the photovoltaic field, due to the boosted efficiency up to 22.1%. Despite a flow of achievements, there are certain challenges to simultaneously meet high efficiency, large scale, low cost and high stability. Due to the low cost, extensive sources, high electrical conductivity and chemical stability, carbon materials have made undeniable contributions to play positive roles in developing PSCs. Carbon materials not only have the favorable conductivity but also bipolar advantage, which can transfer both electrons and holes. In this review, we will discuss how the carbon materials transfer charge or accelerate charge transport by incorporation in PSCs. Carbon materials can replace transparent conductive oxide layers, and enhance electron transport in electron transport layers. Moreover, carbon materials with continuous structure, especially carbon nanotubes and graphene, can provide direct charge transport channel that make them suitable additives or even substitutes in hole transport layers. Especially, the successful application of carbon materials as counter electrodes makes the devices full-printable, low temperature and high stability. Finally, a brief outlook is provided on the future development of carbon materials for PSCs, which are expected to devote more contributions in the future photovoltaic market.
A poly (acrylic acid-co-N-methylol acrylamide-co-butyl acrylate) copolymer grafted-carboxymethyl cellulose (PA-PN-PBA-g-CMC) binder is synthesized via a free radical copolymerization for Si-based anodes in lithium ion batteries. In this multifunctional polymer binder system, carboxyl-rich poly (acrylic acid) and carboxymethyl cellulose can bond with Si particles and copper current collectors. Additionally, a robust cross-linking network can be obtained through the condensation reaction between hydroxyl and hydroxymethyl groups which are present in carboxymethyl cellulose and N-methylol acrylamide segments, respectively. This network structure helps to keep the integrity of the Si electrode, and thereby significantly improves the cycling performance of the Si anodes (capacity retention rate after 200 cycles is above 90%). The butyl groups in poly (butyl acrylate) segments provide the nonpolar sections in the binder, which help the electrolytes easily wet the electrodes, allowing Li ions to diffuse rapidly in the Si anodes. With this multi-functional binder, the Si-based LIBs perform well in both cycle performance and rate performance.
Lithium iron phosphate (LFP) cathodes are one of the most promising candidates to find application in hybrid electric vehicle energy storage system. For this reason advances in the performance of its theoretical capacity at high charge/discharge rates is under continuous development. Most used strategies to improve power performance are the addition to the LFP particles of an electric conductive carbon or polymer, such as poly(3,4-ethylenedioxythiophene) [PEDOT] doped with polystyrene sulfonate (PSS). The data obtained from impedance analysis provide new insight on the role of these additives that not only improve the charge transfer but also favor the lithiation/delithiation processes in the phosphate matrix. Furthermore, PEDOT is capable to reduce the resistances of charge transfer and lithiation reaction inside the phosphate matrix by one order of magnitude in comparison with those achieved with the carbon coating strategy. In this study, the most effective approach has been the addition of PEDOT by a blending method, resulting in a specific capacity of 130mAhgLFP −1 at 2C.
Chemically regenerative redox cathode (CRRC) polymer electrolyte fuel cells (PEFCs), where the direct reduction of oxygen is replaced by an in-direct mechanism occurring outside of the cell, are attractive to study as they offer a solution to the cost and durability problems faced by conventional PEFCs. This study reports the first detailed characterization of a high performance complete CRRC PEFC system, where catholyte is circulated between the cathode side of the cell and an air-liquid oxidation reactor called the “regenerator”. The catholyte is an aqueous solution of phosphomolybdovanadate polyoxoanion and is assessed in terms of its performance within both a small single cell and corresponding regenerator over a range of redox states. Two methods for determining regeneration rate are proposed and explored. Expressing the regeneration rate as a “chemical” current is suggested as a useful means of measuring re-oxidation rate with respect to the cell. The analysis highlights the present limitations to the technology and provides an indication of the maximum power density achievable, which is highly competitive with conventional PEFC systems.
In-wheel motors (IWMs) substantially influence the output performance of electric vehicles (EVs). Size design and control issues are two critical factors to be explored. This paper proposes the use of hybridization for integrating dual motors to enhance EV system dynamics. A combined optimal sizing/control approach was developed using the global search method (GSM). The optimal control (torque ratio) of dual motors was first proposed using the nested-structure for-loop program to minimize the consumed power according to various power ratios. The next combined sizing/control developed using the GSM facilitated the search for the optimal control, power ratios, and T–N (Torque–Speed) ratios to minimize the accumulated energy consumed during ECE40 and UDDS driving cycles. The results from simulations of these two cycles indicated that the energy consumption during optimal control improved by 1.23% and 1.40%, 8.34% and 7.16% after optimal sizing, and the combined optimization improved total consumed energy by 15.31% and 15.16%, respectively. These results suggest that employing the novel hybrid IWM powertrains while using the combined sizing/control method can facilitate energy conservation. A real testing platform will be developed in the future.