batterydata/paper-abstracts huggingface dataset:
Microsized single-crystal Li1.08Mn1.89Al0.03O4 (LAMO) was synthesized via polyvinylpyrrolidone (PVP) combustion method. X-ray diffraction (XRD), scanning electron microscope (SEM) and high-resolution transmission electron microscopy (HRTEM) characterization results indicate that the as-prepared LAMO has good crystallinity, uniform and smooth-surfaced morphology, and very low specific surface area. Galvanostatic charge-discharge tests demonstrate its excellent electrochemical performance. The capacity retentions at 30 °C and 55 °C are 98.8% and 93.3% respectively after 200 cycles at 1 C charge/discharge rate. Moreover, the LAMO exhibits excellent rate and low temperature performance. Even at high rates of 40 C and 60 C, the as-prepared LAMO are still able to deliver 91.2% and 85.6% capacity relative to the discharge capacity at C/5. The specific discharge capacity at −20 °C is 97.9 mAh g−1 which is 93.7% of the capacity discharging at 25 °C. To study the reason of the excellent rate performance, the potential intermittent titration technique (PITT) tests and cyclic voltammetry (CV) measurements were conducted and the lithium chemical diffusion coefficient ( D Li + ) was calculated.
Renewable energy sources are certain to play a key role in the future energy generation due to the rapid depletion of conventional sources of energy. The solar and wind energy are the major renewable energy sources which have the potential to meet the energy crisis to some extent. However, such sources when explored independently are not completely reliable because of the unpredictable nature. Whereas their use as hybrid energy systems seems to be more reliable and cost effective, due to the complementary nature of these two resources. In this paper an attempt has been made to discuss a systematic review related to hybrid PV/wind energy systems with battery storage. The work as presented in the manuscript will help the researchers to explore such hybrid energy systems for further improvements in terms of designing, analyzing and integrating such systems into the power network.
Edgar Douglas Adrian, a dominating figure of 20th century electrophysiology, published in 1912 a study on the effects of the conduction block induced by application of alcohol vapours to small segments of nerves from which he derived the conclusion that nerve signals regenerate along the nerve fibre during the conduction process. This conclusion was based on results of experiments in which the time required to produce a conduction block was found to decrease as the length of the nerve segment treated was increased. These results could not be confirmed when similar experiments were performed about 10 years later by Gen'ichi Kato, a leading figure of Japanese physiology and founder of one of the great schools of Japanese electrophysiology. Directly or indirectly, the Adrian–Kato controversy was at the inception of two of the most important advancements of 20th century neurophysiology: the elucidation of the mechanism of nervous conduction in squid giant axon by Hodgkin and Huxley and the discovery of the saltatory conduction in myelinated nerve fibres by Tasaki, Takeuchi, Huxley and Stämpfli. This controversy is also interesting for its epistemological aspects, which is important now to re-evaluate.
In the present work, we demonstrate the electrochemistry of nanocrystalline TiO2 in anatase (TiO2-A), anatase/rutile (TiO2-C) and rutile (TiO2-R) phases. Cyclic voltammetry (CV), galvanostatic charge-discharge, and electrochemical impedance spectroscopy were the techniques we employed to analyse the electrochemical properties of the electrodes. The observed results suggest that the electrode of TiO2-A possesses superior electrochemical properties due to its enhanced BET surface area, porous structure and low charge transfer resistance. At a low scan rate of 10mV/s, CV analysis results imply a capacitance of 362F/g for TiO2-A. Moreover, the galvanostatic charge-discharge study gives a specific capacitance of 312F/g at a low scan rate of 10A/g. Based on the higher energy density (882Whkg−1) and power density (1260kWkg−1), the TiO2-A electrode is a promising electrode material for fabricating supercapacitors.
S-Co(OH)2 composite is prepared via a facile co-precipitation method and investigated as negative electrode of Ni/Co battery. The addition of amorphous S improves the electrochemical properties of Co(OH)2 electrode. The discharge capacity of S-Co(OH)2 electrode can reach 413.2mAhg−1 and still keep about 340mAhg−1 after 300 cycles, which is much higher than that of S-free Co(OH)2 electrode. Amorphous S in S-Co(OH)2 electrode shows two functions during the charge–discharge process. One is that the addition of amorphous S with high specific surface area improves the dispersion of Co(OH)2 platelets. The other is that the dissolution of amorphous S in electrode brings the new interspaces among the Co(OH)2 platelets, these two factors largely increase the interspaces among Co(OH)2 platelets. More interspaces are correlated to larger contact area with alkaline solution, which is in favor of the surface electrochemical redox. Thus, the capacity utilization of Co(OH)2 is enhanced.
The activity of non-precious metal catalysts (NPMCs) has now reached a stage at which they can be considered as possible alternatives to Pt for some proton exchange membrane fuel cell (PEMFC) applications. However, challenges still remain in achieving acceptable stability (performance during potentiostatic or galvanostatic experiments). The most widely reported hypotheses for the instability of NPMCs include de-metalation, protonation/anion binding, and generation of H2O2. Recently, it has been proposed that the largest contribution to the instability of NPMCs is from flooding of micropores within the catalyst particles leading to significant mass transport limitations. While indirect evidence has been obtained that appears to support this hypothesis, no study has yet been performed to directly target micropore flooding. In this work, a systematic study is performed to investigate micropore flooding in situ before and after stability testing. The results do not support micropore flooding as being a large contributor to instability, at least for the family of NPMCs evaluated in this work. The protocol outlined here can be used by other researchers in the NPMC community to diagnose micropore flooding in their own respective catalysts.
The capacity fading of an 18650 LiFePO4-based lithium ion cell was studied using the dynamic stress test (DST) schedule in a cycle life evaluation. Intermittent reference performance tests were conducted to quantify capacity loss and peak power capability degradation with cycle number to the end-of-life. An incremental capacity analysis was applied to identify various contributions to capacity loss, whereas the open circuit voltage measurements were utilized to trace the correct state of charge as the cell degrades in order to accurately correlate the capacity degradation with SOC. Our non-invasive, in situ analyses are in general consistent with current understanding of the degradation mechanism in this chemistry derived from post-mortem analysis. Loss of lithium inventory is the main cause of capacity degradation, in addition to the loss of active materials. The degree of under-discharge and under-charge is quite minimal under the test protocol.
Transpiration of well-watered and regulated deficit irrigated (RDI) citrus trees was determined by sap flow (SF) measurements using the compensation heat-pulse method. Its potential for detection of plant water stress was evaluated in comparison with measurements of midday stem water potential (ψstem). The study was carried out during 2 years in two commercial groves of Clementina de Nules (CN) and Navel Lane Late (NLL). SF measurements were taken in two trees per treatment instrumented with two identical gauges per tree in NLL and two different types of gauges (type 1 shorter than type 2) in CN. The absolute SF values underestimated the tree water use. Averaged over the entire period of water restrictions, a reduction of about 50 % in water application in the RDI trees of both species decreased tree transpiration compared to the control trees only by a 15 %. Both the nocturnal-to-diurnal SF ratio and the relative transpiration were in good agreement with differences in ψstem. Overall, results suggest that SF measurements should be preferentially used in relative terms. Sap flow sensors are useful for detecting plant water stress, but they also highlight some of the problems for accurately measuring transpiration.
Carbon materials have been widely used to form cathodes for non-aqueous lithium–oxygen batteries. A critical problem with the use of carbon in this type of battery, however, is corrosion. To address this issue, we propose and fabricate a non-carbon cathode electrode consisting of MnO2-deposited stainless steel (SS) felts. Amorphous MnO2 layer are electrodeposited on the surfaces of SS fibers at an anodic current in a manganese acetate solution. The use of the MnO2–SS electrode in a non-aqueous lithium–oxygen battery delivers a specific capacity of 1780 mA h g MnO 2 - 1 . Furthermore, the discharge/charge cycle test with a fixed capacity of 500 mA h g MnO 2 - 1 shows that this electrode can discharge/charge for more than 10 cycles without degradation. It is, therefore, expected that this novel non-carbon and stable cathode is a promising electrode for high-performance lithium–oxygen batteries.
AMP397 is a novel antiepileptic agent and the first competitive AMPA antagonist with high receptor affinity, good in vivo potency, and oral activity. AMP397 has a structural alert (aromatic nitro group) and was mutagenic in Salmonella typhimurium strains TA97a, TA98 and TA100 without S9, but negative in the nitroreductase-deficient strains TA98NR and TA100NR. The amino derivative of AMP397 was negative in wild-type strains TA98 and TA100. AMP397 was negative in a mouse lymphoma tk assay, which included a 24h treatment without S9. A weak micronucleus induction in vitro was found at the highest concentrations tested in V79 cells with S9. AMP397 was negative in the following in vivo studies, which included the maximum tolerated doses of 320mg/kg in mice and 2000mg/kg in rats: Muta™Mouse assay in colon and liver (5×320mg/kg) at three sampling times (3, 7 and 31 days after the last administration); DNA binding study in the liver of mice and rats after a single treatment with [ 14 C ]-AMP397; comet assay (1×2000mg/kg) in jejunum and liver of rats, sampling times 3 and 24h after administration; micronucleus test (2×320mg/kg) in the bone marrow of mice, sampling 24h after the second administration. Based on these results, it was concluded that AMP397 has no genotoxic potential in vivo. In particular, no genotoxic metabolite is formed in mammalian cells, and, if formed by intestinal bacteria, is unable to exert any genotoxic activity in the adjacent intestinal tissue. These data were considered to provide sufficient safety to initiate clinical development of the compound.
A new technology for grid production by electroforming is found to improve grid properties and thus, to increase cycle-life, save costs, and increase the ecological efficiency of lead–acid batteries beyond the corresponding features of competing designs. The particular aspects of the superior corrosion behaviour of the new grids are addressed with respect to the effects of chemical and anodic processes, microstructure, corrosion-induced creep and grid growth, and adherence of the positive active-mass. Along with each of these factors of influence, the prospects for improving battery behaviour and lowering cost is also discussed. The properties achievable by using electroformed grids are presented in terms of experimental results from a comparison with the properties of conventional grids, and by modelling and simulation.
Objective We sought to investigate the activity of bilateral parietal and premotor areas during a Go/No Go paradigm involving praxis movements of the dominant hand. Methods A sentence was presented which instructed subjects on what movement to make (S1; for example, “Show me how to use a hammer.”). After an 8-s delay, “Go” or “No Go” (S2) was presented. If Go, they were instructed to make the movement described in the S1 instruction sentence as quickly as possible, and continuously until the “Rest” cue was presented 3s later. If No Go, subjects were to simply relax until the next instruction sentence. Event-related potentials (ERP) and event-related desynchronization (ERD) in the beta band (18–22Hz) were evaluated for three time bins: after S1, after S2, and from −2.5 to −1.5s before the S2 period. Results Bilateral premotor ERP was greater than bilateral parietal ERP after the S2 Go compared with the No Go. Additionally, left premotor ERP was greater than that from the right premotor area. There was predominant left parietal ERD immediately after S1 for both Go and No Go, which was sustained for the duration of the interval between S1 and S2. For both S2 stimuli, predominant left parietal ERD was again seen when compared to that from the left premotor or right parietal area. However, the left parietal ERD was greater for Go than No Go. Conclusion The results suggest a dominant role in the left parietal cortex for planning, executing, and suppressing praxis movements. The ERP and ERD show different patterns of activation and may reflect distinct neural movement-related activities. Significance The data can guide further studies to determine the neurophysiological changes occurring in apraxia patients and help explain the unique error profiles seen in patients with left parietal damage.
Heavy metal poisoning is an increasing problem due to the growth of industrial activities that involve manipulation of metals, such as mining, foundries and metallurgy in general. Human exposure to these toxic ions and their absorption during the digestive process results in ion accumulation mainly into bone structure, due to the tendency of ionic exchange chemistry of hydroxyapatite (HA) with metal ions. In the last few years, new improvements on materials processing techniques have opened the door to the development of new forms of material, HA/biopolymer foams. These systems allow heavy metal removal, facilitated by their aqueous stability and integrity 3D-macroporous shape, to provide an easily applicable technology for polluted water that avoids the need for purification procedure steps. Moreover these materials are applicable for biomedical use, to capture and immobilize toxic ions during the digestive process. This work reviews the latest procedures to synthesise and fabricate foams based on HA/biopolymer systems for these goals paying special attention to their heavy metal capture applications. In addition, the 3D interconnected architectural design of these HA/biopolymer foams, suggested that they could fit all the requirements to behave as a proper bone scaffold with applications in bone tissue engineering.
Chemical sciences are on continuous evolution offering more and more complex synthetic strategies that rely on emerging inter- and trans-disciplinary vocation. In this tutorial review, we demonstrate how integrative chemistry, through combining soft matter and soft chemistry, allows positioning chemical reactors within the geometric space. Therefore, we focus the examples on biliquid foam oil/water interfaces and sol–gel chemistry. In this view we distinguish between diluted and concentrated emulsions, acting respectively as discrete chemical reactors and percolated ones. Along the manuscript, non-exhaustive morphosyntheses of advanced functional materials are proposed when dedicated either to heterogeneous biocatalysts, energy conversion systems and thermo-stimulated delivery of encapsulated substances.
DNA methylation is a key epigenetic modification of DNA that is catalyzed by DNA methyltransferase (DNMT). Increasing evidence suggests that DNA methylation in neurons regulates synaptic plasticity as well as neuronal network activity. Here, we evaluated DNA methyltransferase 1 (Dnmt1) and Dnmt3a expression in brain tissues of epileptic patients to explore their possible role in epileptogenesis. Tissue samples from temporal neocortices of 25 patients with intractable temporal lobe epilepsy (TLE) and ten histologically normal temporal lobes from control patients were used to detect Dnmt1 and Dnmt3a expression through immunohistochemistry, immunofluorescence, and Western blotting analysis. We found that both Dnmt1 and Dnmt3a expression were principally expressed in the nucleus and the cytoplasm of NeuN-positive neurons, but not in GFAP-positive astrocytes. Levels of the two DNMT proteins were significantly increased in patients with TLE. Our study suggests that DNMT1 and DNMT3a may play a role in the pathogenesis of TLE.
The concentration at which the camel-bell shape transition occurs in the capacitance curve of electric double layer capacitors is predicted via a new regularity stating that various plots of the integral capacitance, related to different surface charge densities, versus concentration (i.e., Cs-C
is Group Leader Product Management at the Krauss Maffei Automation GmbH in Oberding-Schwaig (Germany).
Power battery packs are the energy source of battery electric vehicles (BEVs). A precise state-of-health (SOH) estimation for batteries is crucial to ensure the operational security and stability of BEVs. This paper employs an equivalent circuit model of battery pack in SOH estimation. Since a battery pack is a complex and nonlinear system, the equivalent circuit model of battery pack is always complicated. To balance estimation accuracy and computational complexity, the equivalent circuit model of battery pack should be simplified. However, much noise is produced in the simplified model. In addition, the errors during SOH estimation are from various sources so that SOH estimation is a non-Gaussian problem. Given the genetic resampling particle filter (GPF) performs efficiently in solving non-Gaussian problems, this paper proposes a new GPF-based method for battery SOH dynamic estimation when accuracy of the equivalent circuit model is not high. First, a second-order equivalent circuit model of Resistance–Capacitance (RC) circuit for the battery pack is developed. The unknown parameters are identified using the recursive least-squares method with forgetting factor. Second, a state-space model of the GPF is developed based on the equivalent circuit model. Finally, a case study is conducted using real data collected from operating electric taxis in Beijing to investigate the estimation performance of the proposed model. Estimation results show that the proposed GPF model outperforms the particle filter method in the SOH estimation problem.
Supercapacitor electrodes fabricated from multiwalled carbon nanotubes (MWCNTs) and poly-3,4-ethlyenedioxythiophene–polystyrenesulfonate (PEDOT–PSS) with different mass ratios (MWCNTs:PEDOT–PSS=95:5, 90:10, 70:30, 50:50) were examined and compared with the electrode composed of MWCNTs and polytetrafluoroethylene (PTFE). The cyclic voltammetry (CV) results show that the MWCNTs/5wt% PEDOT–PSS composite owns the highest specific capacitance, while the MWCNTs/50wt% PEDOT–PSS composite can maintain the best capacitive behavior at higher scan rates and frequencies from the CV and EIS (electrochemical impedance spectroscopy) data. The EIS and CV results show the loss of electroactive species in PEDOT–PSS during continuous cycling. The transmission electron microscopy shows that the MWCNTs are partly covered with the polymers. The results of time-of-flight secondary ion mass spectrometry and X-ray photoelectron spectrometry reveal that the conjugation path in the backbone of PEDOT is damaged, leading to the decline of the redox peaks in CV for the MWCNTs/PEDOT–PSS composites during continuous cycling. Whereas, the –SO3 − groups in PSS retains integrity during continuous cycling, and they can still contribute to the capacitance of the composite; therefore, when compared with the MWCNTs/10wt% PTFE composite, the MWCNTs/10wt% PEDOT–PSS composite can remain higher specific capacitance, and maintain the capacitive characteristics at higher scan rates.
Material failures occur in products due to changes in the original characteristics that prevent satisfactory performance of a functional system for its intended purpose and could produce losses to human life and economic infrastructure. Metals’ characteristics change due to cyclic stress, strain, and corrosion. This paper presents a case study that deal with the application of corrosion fundamentals in the determination of the origin of failures in a metallic part—galvanic corrosion failure in a water supply plumbing system. Metallographic examination, chemical analysis of the parts, and fractography were conducted, and the cause of failures was determined as a galvanic corrosion.
Abstract Computer models help researchers understand the peripheral nervous system. Often models are used to investigate a cell’s response to changes in the electrochemical environment. Models range from very simple axon models that do not propagate action potentials to very complex, networked populations of neurons and can broadly be divided into point models and compartmental models. In both model types, the neural membrane behaves like and is modeled as a capacitor and resistor in parallel. Most ion channels are modeled as a variable resistor. Chemical ionic gradients across the membrane are modeled as batteries. These four components—capacitors, passive and variable resistors, and batteries—form the basis of neural models ranging from the simple integrate-and-fire to the very complex multicompartmental representations of branching, myelinated axons.
Solar energy generation and utilization is dominated by silicon based solar photovoltaic technology, which has a market share of 80–90% of the solar photovoltaic industry worldwide. The performance indicating parameters of silicon solar cells include power conversion efficiency, series and shunt resistance, ideality factor and built-in potential. These parameters are mostly characterized by DC techniques, which is limited by its insufficiency to identify other important parameters such as interfacial diffusion and transition capacitance and resistive and capacitive components of p-p+ interface of a silicon solar cell. Impedance spectroscopy is considered to be one of the most promising techniques for the characterization of abovementioned performance limiting parameters of a solar cell. In order to address the decoupling of various physical processes associated with different interfaces of a solar cell, quantitative analysis of the impedance spectroscopic data is required. An appropriate mathematical model is frequently used to correlate with the physical performance limiting parameters. This review presents a complete overview of the required mathematical models to analyse impedance spectroscopic data for interfacial processes of silicon solar cell.