batterydata/paper-abstracts huggingface dataset:
One-layer sol–gel silica–zirconia and two-layer silica–zirconia and zirconia coatings were deposited on one side of iron membranes by spin-coating, densified in air and annealed up to 800°C in vacuum. Hydrogen permeation through the membranes, coated and uncoated, polarised cathodically under galvanostatic control in 0.1M NaOH solution was studied using the electrochemical permeation technique. During the initial period, the effect of the sol–gel coatings was insignificant. However, the coatings quite efficiently prevented the iron surface become more active to hydrogen entry during a long-lasting cathodic polarisation. In addition, the electrochemical-corrosion behaviour of the coated iron and the effect of the sol–gel coatings on the effective diffusivity of hydrogen in the coated membranes were studied. On the basis of the polarisation curves and the hydrogen permeation data it was proved that the sol–gel coatings blocked the iron surface for the hydrogen evolution reaction and, consequently, for the hydrogen entry into iron. The effective coating coverage was determined by comparison of the hydrogen fluxes permeating the coated and uncoated membranes. Finally the real concentration of hydrogen beneath the uncoated iron sites and the amount of hydrogen stored in a membrane were evaluated.
Polymerization of luminol performed in strongly acidic aqueous solution can produce thin electrochemically active films of one redox couple. The film can be produced on glassy carbon, platinum, gold and transparent semiconductor tin(IV) oxide electrodes. An electrochemical quartz crystal microbalance and cyclic voltammetry were used to study in situ growth of the polyluminol film. The modified film is electrocatalytically active for NADH oxidation in acidic and neutral aqueous solutions, and the electrocatalytic oxidation current develops from the anodic peak of the redox couple. The direct electrocatalytic oxidation of epinephrine, dopamine, ascorbic acid, and l-cysteine by the polyluminol film in acidic and neutral aqueous solutions also shows electrocatalytic oxidation activity. The electrocatalytic oxidation properties of dopamine, ascorbic acid, and epinephrine by polyluminol film in the presence of mixtures of the three compounds or of only one compound are also discussed. The results show a selective measurement of dopamine and ascorbic acid. The polymer films were more stable in acidic solutions, their formal potentials being pH-dependent with a slope of −58 mV pH−1.
Spectra Watermakers Inc of San Rafael, California, USA, which develops energy-efficient water treatment systems and energy recovery pumps, has delivered two of its solar-powered ultrafiltration (UF) units to the US Army stationed in Afghanistan. The firm has also provided details of its recently developed Pearson Pump energy-recovery system.
Micro-sized Li4Ti5−xBixO12 (0 ≤ x ≤ 0.15) materials are synthesized using a simple solid state method in air. The structural, morphological, and electrochemical characteristics of Bi-doped lithium titanates and pristine samples are methodically analyzed by X-ray diffraction (XRD), Raman spectroscopy, field emission-scanning electron microscopy (FE-SEM), and electrochemical impedance spectroscopy (EIS). The XRD and Raman spectroscopy results demonstrate that bismuth-doping do not alter the spinel structure and good crystalline materials are synthesized. The FE-SEM images show that all samples possess the same morphological characteristics, with a particle size distribution of 0.5–1 μm. The electrochemical cycling testing reveals that the Li4Ti4.9Bi0.10O12 sample exhibits discharge capacities of 205.4 mAh g−1, 160.8 mAh g−1, and 135.4 mAh g−1 after 50 cycles at 1C, 5C, and 10C-rates, respectively. The differential capacity curves suggest that the Li4Ti4.9Bi0.10O12 sample has a weaker polarization effect than the other samples. The EIS measurements imply that the Li4Ti4.9Bi0.10O12 sample possesses a high electronic conductivity and lithium ion diffusivity, which demonstrate that this new Li4Ti4.9Bi0.10O12 material would be a good candidate as an anode for lithium ion batteries.
Lithium-sulfur (Li-S) battery is a promising energy storage technology to replace lithium ion batteries for higher energy density and lower cost. Dissolution of lithium polysulfide intermediates in conventional Li-S electrolytes is known as one of the key technical barriers to the development of Li-S, because it promotes redistribution and irreversible deposition of Li2S, and also forces large amounts of electrolyte to be used, shortening cycling life and driving down cell energy density. Recently, dimethyl disulfide as a functional co-solvent has been demonstrated to show an alternate electrochemical reaction pathway for sulfur cathodes by the formation of dimethyl polysulfides and lithium organosulfides as intermediates and reduction products. In this work, comprehensive studies show that this new pathway not only provides high capacity but also enables excellent capacity retention through a built-in automatic discharge shutoff mechanism by tuning carbon/sulfur ratio in sulfur cathodes to reduce unfavorable Li2S formation. Furthermore, this new electrolyte system is also found to enable high capacity of high-sulfur-loading cathodes with low electrolyte/sulfur (E/S) ratios, such as a stable specific capacity of around 1000mAhg−1 using a low electrolyte amount (i.e, E/S ratio of 5mLg−1) and high-sulfur-loading (4mgcm−2) cathodes. This electrolyte system almost doubles the capacity obtained with conventional electrolytes under the same harsh conditions. These results highlight the practical potential of this electrolyte system to enable high-energy-density Li-S batteries.
Publisher Summary This chapter discusses the types of lead-acid (secondary) batteries, such as motive power batteries. Motive power lead-acid batteries are the power source used in every kind of electric vehicle from road transport to fork lift trucks in industry. Many manufacturers throughout the world supply lead-acid batteries and it is impossible to review all their products. Instead, the products of one major UK-based international producer, Chloride Motive Power, are considered in detail. The other type of battery discussed is standby power batteries; these are designated as high-performance types. The nominal voltage is 2V/cell, i.e. a nominal l l0V battery will have 55 cells. On discharge, the recommended final voltage at which the discharge should be terminated is highlighted in the chapter.
Silicon-based electrolyte has emerged as a primary candidate for the development of large lithium-ion batteries for electric vehicle (EV) and other systems in which safety is a primary consideration. Comparing to the electrolyte used in the conventional lithium-ion batteries, which are flammable, volatile, and highly reactive organic carbonate solvents, silicon-based electrolytes are thermally and chemically stable, less flammable and environmental benign. Tri(ethylene glycol)-substituted trimethylsilane (1NM3) was identified as a focus of investigation due to its high conductivity and low viscosity. We present the results of a systematic investigation of the 1NM3-based electrolytes with lithium bis(oxalate)borate (LiBOB) salt, including temperature dependent ionic conductivity and lithium cell performance. Lithium-ion cell with LiNi1/3Co1/3Mn1/3O2 as the positive electrode and MAG graphite as the negative electrode has shown excellent cyclability using 1NM3-LiBOB as electrolyte.
In this work, heterogeneous sulfonation and both, structural and electrical characterization of a mixture composed on block copolymer ionomers (HSBS and EPDM) and commercial silica, are studied. The incorporation of sulfonic groups was checked by infrared spectroscopy (FTIR-ATR). Microstructure was studied by means of dynamic mechanical analysis (DMA). Also, water uptake and methanol crossover were determined, and the results were compared with those of Nafion® 117. Electrical behavior was recorded by means of electrochemical impedance spectroscopy (EIS) at different hydration times. Results show that sulfonation of the styrene rings has effectively occurred. Conductivity values are similar to Nafion and they improve with hydration time. Methanol crossover is lower than in Nafion. Finally, a single complete proton exchange membrane fuel cell (PEMFC) as a whole was tested obtaining the polarization and power curves at different temperatures and pressures, and modeling it by an electrical equivalent circuit (EC) in the symmetrical mode (SM) configuration using the EIS technique. This study offers a physical interpretation relating physical parameters to several processes occurring in the system. Power density values are higher than in Nafion.
Anion exchange membrane (AEM) water electrolysis is a hydrogen production method that is achieved with an AEM, using electricity. One of the major advantages of AEM water electrolysis is the replacement of conventional noble metal electrocatalysts with low cost transition metal catalysts. AEM electrolysis is still a developing technology; therefore, with a view to using it to eventually achieve commercially viable hydrogen production, AEM electrolysis requires further investigation and improvements, specifically regarding its power efficiency, membrane stability, robustness, ease of handling, and cost reduction. This review addresses state of the art technology of AEM electrolysis for hydrogen production. It also provides a summary of important research that has been carried out on membranes, electrocatalysts, and ionomers used in AEM electrolyzers, and the performance of such electrolyzers. The aim of this review is to identify gaps in AEM water electrolysis research and to make recommendations for future directions in AEM water electrolysis research.
The development of cognitive functions and the sustainability of seizure control between two and ten years after epilepsy surgery were prospectively investigated in 17 children and adolescents. Intelligence quotient remained stable. Learning capacity improved. Verbal memory improved in half of the subjects and declined in half, whereas figurative memory declined in most patients. Working memory improved as did attention regarding sustained attention and impulse control. In contrast, reaction times were longer, and the auditory attention span was shorter. Executive functions were not affected. Six subjects (35%) were seizure free at the 10-year follow-up, and a seizure reduction of more than 75% had been achieved in 13 (76%). Seizure control improved in five and seizures recurred in two subjects between the two- and the 10‐year follow-up.
A cheap and rapid supercritical hydrothermal method has been adopted for the synthesis of Li2FeSiO4 cathode materials for the application in lithium ion battery. The as-synthesized Li2FeSiO4 particles at 380°C exhibited rod like morphology with 20–80nm in diameter and 500nm–1μm in length characterized by transmission electron microscopy (TEM). The Li2FeSiO4 material is systematically characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TG), scanning transmission electron microscopy (STEM) and energy dispersive X-ray (EDX). The electrochemical measurements were carried out after coating of Li2FeSiO4 particles with different weight percentage of conductive carbon. The discharge capacity of as-synthesized rod like Li2FeSiO4 with 30wt% conductive carbon coating exhibited 177mAhg−1 for the first cycle, which is more than that of as-synthesized and 20wt% conductive carbon coated rod like Li2FeSiO4 particles. The obtained discharge capacity is the highest for this material without high temperature heat treatment, which indicating that rod like morphology with diameter 20–80nm could be more active during electrochemical reactions.
Tin oxide and amorphous tin borophosphates have recently received significant attention as possible new negative electrode materials for lithium batteries. In this study, we have carefully investigated a number of different well-characterised tin phosphates as electrodes in Li-ion cells, in order to better understand the mode of operation of these materials and how their performance is related to structure and composition. The materials that were investigated were crystalline cubic and layered SnP2O7, LiSn2(PO4)3, Sn2P2O7, and Sn3(PO4)2, and amorphous Sn2BPO6. Cubic SnP2O7 showed the best performance with a reversible specific charge capacity of >360 mA h g−1 and a capacity retention of 96% over 50 cycles when cycled between 0.02 and 1.2 V versus Li m . The three Sn(IV) materials showed lower initial reversible capacity but better capacity retention than the three Sn(II) materials in the study. Their higher proportion of inert matrix material can partly explain this. However, cubic SnP2O7 cycled significantly better than its layered polymorph, which shows that the structure of the starting material is also of great importance. Another important conclusion drawn from the results is that it is not necessary for the starting material to be amorphous, or if crystalline, to have small grain size, to cycle well. The three pyrophosphates all show an initial reduction capacity that corresponds to around 2 Li per P2O7 4− unit more than is predicted by theory. This might be explained by reductive break-up of the POP bond.
The effect of pore structure on anomalous behaviour of the lithium intercalation into porous V2O5 film electrode has been investigated in terms of fractal geometry by employing ac-impedance spectroscopy combined with N2 gas adsorption method and atomic force microscopy (AFM). For this purpose, porous V2O5 film electrodes with different pore structures were prepared by the polymer surfactant templating method. From the analysis of N2 gas adsorption isotherms and the triangulation analysis of AFM images, it was found that porous V2O5 surfaces exhibited self-similar scaling properties with different fractal dimensions depending upon amount of the polymer surfactant in solution and the spatial cut-off ranges. All the ac-impedance spectra measured on porous V2O5 film electrodes showed the non-ideal behaviour of the charge-transfer reaction and the diffusion reaction, which resulted from the interfacial capacitance dispersion and the frequency dispersion of the diffusion impedance, respectively. From the comparison between the surface fractal dimensions by using N2 gas adsorption method and AFM, and the analysis of ac-impedance spectra by employing a constant phase element (CPE), it is experimentally confirmed that the lithium intercalation into porous V2O5 film electrode is crucially influenced by the pore surface irregularity and the film surface irregularity.
In 1998, a total of 424 sows had sera collected in the Mekong delta in Vietnam. Of these, 283 sows were from 151 small-scale family farms in 19 villages, and 141 from seven large-scale state farms. The sera were subjected to the microscopic agglutination test (MAT) for antibodies to 13 Leptospira serovars. The overall leptospiral seroprevalence for titres ≥1:100 and ≥1:400, was 73 and 29%, respectively, and was higher (P=0.001) at small- than at large-scale farms. The highest seroprevalence was recorded for Leptospira interrogans serovar (sv) bratislava (52%). At small-scale farms, higher prevalences were found to serovars L. interrogans sv icterohaemorrhagiae (P=0.04) and L. interrogans sv pomona (P=0.02). Epidemiological information (at the individual-animal and herd-levels) was collected with a questionnaire. The data were analysed using logistic multiple regression. At the animal-level, sows seropositive for L. interrogans sv australis and sv autumnalis had less direct contact with sows in neighbouring pens (odds ratio (OR)=0.3 and 0.4, respectively) and sows seronegative for L. interrogans sv bratislava were of lower age (OR=0.1 for seropositivity). Also, sows seropositive for L. interrogans sv icterohaemorrhagiae had higher odds (OR=5.8) if they had not been born on the farm (had been introduced to it as gilts). Herds seropositive for sv javanica showed association with farms not taking measures to control the local rodent population (OR=7.8). Serovar pomona was also linked to the use of artificial insemination (AI), as opposed to natural-breeding services (OR=11.2). These results indicate that housing and management could affect the seroprevalence of Leptospira infection in pigs.
Increasing numbers of drugs are being developed for the treatment of multiple sclerosis (MS). Measurement of relevant outcomes is key for assessing the efficacy of new drugs in clinical trials and for monitoring responses to disease-modifying drugs in individual patients. Most outcomes used in trial and clinical settings reflect either clinical or neuroimaging aspects of MS (such as relapse and accrual of disability or the presence of visible inflammation and brain tissue loss, respectively). However, most measures employed in clinical trials to assess treatment effects are not used in routine practice. In clinical trials, the appropriate choice of outcome measures is crucial because the results determine whether a drug is considered effective and therefore worthy of further development; in the clinic, outcome measures can guide treatment decisions, such as choosing a first-line disease-modifying drug or escalating to second-line treatment. This Review discusses clinical, neuroimaging and composite outcome measures for MS, including patient-reported outcome measures, used in both trials and the clinical setting. Its aim is to help clinicians and researchers navigate through the multiple options encountered when choosing an outcome measure. Barriers and limitations that need to be overcome to translate trial outcome measures into the clinical setting are also discussed.
The use of first-principles computational techniques, such as density functional theory (DFT), to understand electrochemical reactions is witnessing an ever increasing popularity within the physical electrochemistry community. However, applying DFT to electrochemical interfaces is still a challenging and far-from-straightforward process. In the past decade, considerable effort has been put into the development of consistent frameworks able to provide reasonable explanations for several unresolved experimental questions, especially in the field of electrocatalysis. Moreover, there exist some successful examples in which these models have been able to predict and guide experiments, leading to synthesis of catalyst materials with improved activities. Nevertheless, first-principles computational electrochemistry is still a field under development and its accuracy is limited by the size and complexity of the simulated systems. Here we will review the achievements of the free-energy approach, or “computational thermodynamics”, to modeling electrochemical processes and discuss its present and future challenges.
Objective To study brainstem function in Parkinson’s Disease (PD) at different stages, through a battery of vestibular-evoked myogenic potentials (VEMPs) and compare the results with scores on clinical scales assessing the presence of symptoms linked to brainstem involvement. Methods Cervical, masseter and ocular VEMPs were recorded in patients with early PD (n =14, disease duration 1.42±0.7years), advanced PD (n =19, disease duration 7.26±2.9years) and in 27 age-matched controls. In PD, the following clinical scales were administered: Mini-BESTest, REM sleep Behavior Disorder Screening Questionnaire (RBD-SQ), PD Sleep Scale, Epworth Sleepiness Scale and Geriatric Depression Scale. Results Rate of VEMPs alterations was higher (p <0.001) in PD than controls, but similar within PD groups. However, early and advanced PD showed a different pattern of abnormalities (p =0.02), being latency delay prevalent in the former and absence in the latter. VEMP impairment correlated directly with RBD-SQ scores in both PD cohorts and inversely with Mini-BESTest scores in advanced PD. Conclusions VEMPs displayed progressive severity of alterations at different stages of PD, with remarkable correlations with presence of postural instability and RBD. Significance The combined use of VEMPs may provide interesting insights into the pathophysiological mechanisms of PD at the earliest and prodromal stage of the disease.
Second primary tumors (SPTs) significantly increase the mortality in patients with head and neck squamous cell carcinomas (HNSCCs). Virtual chromoendoscopy (VCE) could complement or replace lugol chromoendoscopy (LCE) for early esophageal second primary tumor (ESPT) detection. An overview of the existing techniques and their diagnostic performance in early detection of esophageal squamous cell neoplasms is provided.
Publisher Summary The chapter discusses various pieces and parts that make up an electrical circuit. It starts with semiconductors, which it defines as a material that partially conducts electricity or a material that is only semigood at conducting electricity. The chapter then goes on to discuss various semiconductor devices used in circuits such as diodes and transistors and their different modes of operation. Further, the chapter discusses field effect transistors (FETs) that have some properties that make them very desirable components. The primary reason they are so efficient is that the output of a FET is a resistance that varies depending on the voltage at the input. Next, the chapter describes miscellaneous components such as Darlington transistor, silicon controlled rectifier (SCR), TRIAC, and isolated gate bipolar transistor (IGBT). The chapter further explains the concepts of heat and power management. Finally, the operational amplifiers, positive, and negative feedbacks are described while the popular microcontrollers and microprocessors and their inputs and outputs are also explained.
Powertrain of an electric vehicle (EV) is a compound system with an electrical sub-system, such as batteries, inverters, and electrical motors, as well as a mechanical sub-system, including transmissions, differential, and wheels. Since the electrical systems directly affect the vehicle driving performance and dynamics of an EV, integrated modeling considering both the mechanical and electrical systems is essential to assess ultimate kinetic and dynamic characteristics of an EV in terms of input electrical quantities. In this paper, an entire analytic model for the powertrain of EVs is developed to describe EV dynamics with respect to electrical signals, in consideration of both mechanical and electrical systems. Theoretical models based on mathematical expressions, combining the mechanical power system and the electrical power systems, are derived for predicting the final vehicle driving performance as a function of electrical quantities. In addition, a Matlab model of an EV is developed to verify the derived mathematical analysis model. Based on the theoretical model of the powertrain, a variety of relationships between electrical quantities and vehicle dynamics, such as velocity, acceleration, and forces of the EVs, are finally investigated and analyzed.
With the aim of developing 1kWh class lithium ion batteries with long life and high efficiencies, we trial manufactured batteries that were fabricated using LiCoO2 and natural graphite as cathode and anode materials, respectively, with 1M LiPF6 diluted by EC/DEC as an electrolyte. Fundamental studies necessary for the development of a large-scale battery consisting of laminated large electrodes were conducted, examining various factors. These factors were selected from the observations of batteries dismantled after the battery life reached an end point. The construction of the batteries was based on the results of fundamental research done to elucidate the problems encountered in the present study. We achieved 543 cycles with high efficiencies with the fourth battery. It is noteworthy that technical factors such as homogeneous impregnation of the electrolyte into the electrode laminates and maintenance of uniform conditions of laminates by the control of expansion and contraction accompanied with charge and discharge, respectively, were very important for the long life of large-scale lithium ion batteries.