batterydata/paper-abstracts huggingface dataset:
Comparative electrochemical behavior of self-assembled monolayers (SAMs) of three heteroaromatic thiols, 2-mercaptobenzoxazole (MBO), 2-mercaptobenzothiazole (MBT), and 2-mercaptobenzimidazole (MBI) are investigated by means of cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The electrochemical characteristics of the electrode/solution interface are considerably and differently affected by thiols constructing the SAMs. The consumed charges for reductive desorption of SAMs, which is criterion for the amount of chemically adsorbed thiol, are significantly different for these three SAMs, specially for MBT, implying that SAM of MBT is formed through both sulfur atoms; the thiol sulfur and skeleton sulfur of the thiazole ring. Desorption potentials of the SAMs have shown the following order for strength of gold–sulfur bond: MBT>MBO>MBI. Activity of the three SAMs as pH-sensitive interfaces was also investigated and their surface-pK a values derived from the EIS measurements showed this order for acidic strength of SAMs: MBO>MBT>MBI. This is the same order expected due to the difference in electronegativity of the O, S, and N heteroatoms, and confirms that the most electron-rich ring imidazole is attached to the benzene ring of MBI. A comparison of the interfacial charge transfer resistance variation as a function of gold immersion time in thiols solution reveals that kinetics of Au–MBT assembly is different from those of two others and confirms formation of Au–MBT SAM via both sulfur atoms of MBT.
In this study, a series of nanocomposite polymer electrolytes (CPEs), PAN/LiClO4/SAP, with high conductivity are prepared based on polyacrylonitrile (PAN), LiClO4 and low content of the silica aerogel powder (SAP) prepared by the sol–gel method with ionic liquid (IL) as the template. The effect of addition of SAP on the properties of the CPEs is investigated by FTIR, AC impedance, linear sweep voltagrams and cyclic voltammetry measurements as well as the charge–discharge performance. It is found that the ionic conductivity of the CPE is significantly improved by addition of SAP. The maximum ambient ionic conductivity of CPEs is about 12.5 times higher than that without addition of SAP. The results of the voltammetry measurements of CPE-3, which contained 3wt% of SAP, show that the anodic and cathodic peaks are well maintained after 100 cycles, showing excellent electrochemical stability and cyclability over the potential range between 0V and 4V vs. Li/Li+. Besides, the room temperature discharge capacity measured at 0.5C for the coin cell based on CPE-3 is 120mAhg−1 and the capacity is retained after 20 cycles discharge, indicating the potential for practical use. This is perhaps the first report of the room temperature charge–discharge performance on the solid composite polymer electrolyte to the best of our knowledge.
Objective The aim of this study was to determine if working memory (WM) performance is significantly improved after the delivery of transcranial random noise stimulation (tRNS) to the left dorsolateral prefrontal cortex (DLPFC), compared to an active comparator or sham. Methods Ten participants undertook three experimental sessions in which they received 10min of anodal tDCS (active comparator), tRNS or sham tDCS whilst performing the Sternberg WM task. Intra-stimulation engagement in a WM task was undertaken as this has been previously shown to enhance the effects of tDCS. Experimental sessions were separated by a minimum of 1week. Immediately prior to and after each stimulation session the participants were measured on speed and accuracy of performance on an n-back task. Results There was significant improvement in speed of performance following anodal tDCS on the 2-back WM task; this was the only significant finding. Conclusions The results do not provide support for the hypothesis that tRNS improves WM. However, the study does provide confirmation of previous findings that anodal tDCS enhances some aspects of DLPFC functioning. Methodological limitations that may have contributed to the lack of significant findings following tRNS are discussed. Significance Anodal tDCS may have significant implications for WM remediation in psychiatric conditions, particularly schizophrenia.
The oxygen reduction reaction in a novel trialkoxy ammonium-based ionic liquid, N-ethyl-2-(2-methoxyethoxy)-N,N-bis(2-(2-methoxyethoxy)ethyl)ethan-1-aminium bis(trifluoromethylsulfonyl)imide, [N2(20201)(20201)(20201)] [NTf2] has been studied on glassy carbon and gold electrodes, showing faster electrokinetics on glass carbon because of weaker adsorption of the IL. This has been demonstrated by theoretical calculations and electrochemical studies. In the neat IL, the oxygen is reduced to superoxide (O2 −) through a one electron process; however, better performance is attained in the presence of water (42 mol%), in terms of current density, and onset potential of the reduction process via a reversible 2-electron process. Furthermore, a remarkable increase in cyclic coulombic efficiency is observed for the wet IL (66% in comparison with the neat IL (24%), showing the practicality of a reversible O2/H2O2 system for energy storage.
Publisher Summary This chapter briefly discusses secondary batteries. A classical method of representing a discharge curve for a secondary battery is to plot terminal voltage against time into the discharge at a stipulated battery temperature and constant current discharge rate. Such curves can be prepared at several different battery temperatures in order to establish the effect of temperature on the voltage-time relationship. The voltage characteristics for a cell can be portrayed as a plot of terminal voltage versus discharge time at a stipulated discharge rate and battery temperature. A useful method of studying the effect of temperature on the performance of lead-acid, silver-cadmium and silver-zinc batteries is to plot plateau voltage obtained at various rates of discharge against battery temperature at stipulated rates of discharge. Further, capacity returned-discharge current curves, discharge rate-capacity returned curves, discharge rate-terminal voltage curves, discharge rate-mid-point voltage curves, and discharge rate-energy density curves followed by self-discharge characteristics, float life characteristics.
Carbon-coated, nanostructured Li2MnSiO4 (LMS/C) was synthesized by sol–gel method using a chelating carbonizing source, Glucono-1,5-lactone (GAL). Powder X-ray diffraction studies confirmed nominally pure phase formation. SEM and TEM studies revealed that LMS/C is comprised of particles of less than 50nm in diameter with a thin film of 1–5nm amorphous carbon coating. Elemental mapping demonstrated a homogenous distribution of carbon throughout LMS/C. Besides carbon coating, GAL promotes phase purity and reduces particle agglomeration during annealing. Raman spectroscopic study revealed that the carbon formed in LMS/C nanocomposite is mostly amorphous. The electrochemical performance of LMS/C was evaluated by galvanostatic charge/discharge cycles at various C-rates. We report here a well-defined, flat charge/discharge plateau for LMS/C with extraction/insertion of 1.5 Li+-ion per formula unit at room temperature in a narrow potential window 2.0–4.5V at various current rates. Together with ex situ XPS studies carried out at various states of charge we confirm that the charge and discharge plateaus are associated with the redox chemistry of manganese. LMS/C exhibits a stable discharge capacity for about 10 cycles at various C-rates. However, the capacity fades gradually after 11 cycles at all C-rates. An ex situ XRD study confirmed that the phase was retained up to 10 cycles. The stable cycle-life and the improvement in observed electrochemical performance is attributed to the phase retention in LMS/C nanocomposite.
Cycle performance at 60 °C for a Li Al0.10Ni0.76Co0.14O2 (NCA) cathode/graphite cell was greatly improved when a DOD range in charge–discharge cycling (ΔDOD) was restricted. The deterioration mechanism was analyzed by X-ray photoelectron spectroscopy (XPS), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and scanning transmission electron microscopy-electron energy-loss spectroscopy (STEM-EELS). Only after the cycle test in the ΔDOD of 0–100%, many micro-cracks were generated in the inter-surface between the primary particles which aggregated to form the secondary particles, and a NiO-like resistance layer with Fm3m rock salt structure was formed on each primary particle which was contact with other primary particles and electrolyte. It can be concluded that the lack of contact between the primary particles with the micro-crack generation and the formation of the new resistance layer are responsible for the capacity fading and the rise in impedance during charge–discharge cycle in the wide ΔDOD.
Zeolitic imidazolate frameworks (ZIFs) are widely employed in catalyst synthesis as parental materials for electrochemical energy storage and conversion. Herein, we have demonstrated a facile synthesis of highly efficient catalyst for oxygen reduction reaction in both alkaline and acidic medium, which is derived from ZIF-8 functionalized with ammonium ferric citrate via two-step pyrolysis in Ar and NH3 atmosphere. The results reveal that the catalytic activity improvement after NH3 pyrolysis benefits from mesopore-dominated morphology and high utilization of Fe-containing active sites. The optimum catalyst shows excellent performance in zinc-air battery and polymer electrolyte membrane fuel cell tests.
Background Recent research on schizophrenia indicates that cognitive deficits in this illness are important predictors of functional outcome, highlighting the need for treatments that have a positive impact on cognitive function. Here we explore the hypothesis that acute administration of d-amphetamine can improve cognitive function in individuals with schizophrenia who are well-treated with typical antipsychotics, as well as in healthy controls performing under dual task conditions designed to elicit performance deficits analogous to those found in schizophrenia. Methods Ten individuals with schizophrenia taking haldol or prolixin and 22 healthy controls performed spatial working memory, language production, and Stroop tasks under both placebo and 0.25 mg/kg of d-amphetamine. Results d-Amphetamine improved reactions times on the spatial working memory and Stroop tasks for both individuals with schizophrenia and controls, and improved working memory accuracy in schizophrenia. In addition, d-amphetamine improved language production for both individuals with schizophrenia and controls. Conclusions These results provide support for the hypothesis that the adjunctive administration of dopamine agonist can improve cognitive in individuals with schizophrenia taking typical antipsychotics. The results are discussed in terms of their implications for understanding the nature of working memory deficits in schizophrenia, and potential future avenues for cognitive enhancement in this illness.
The interaction of charged LiNi0.5Mn1.5O4 cathodes in contact with standard electrolyte solvents as e.g. ethylene carbonate and ethyl methyl carbonate is investigated. Due to the high electrochemical potential of the charged LiNi0.5Mn1.5O4 cathode electrolyte decomposition occurs, which results in the formation of gases and other compounds. The corresponding decomposition products are successfully detected and analyzed by means of gas chromatography. We propose that decomposition products react on the surface of the graphite anode, which leads to strong capacity fading. Therefore, an electrochemically active separator containing Li4+x Ti5O12 is used in graphite/LiNi0.5Mn1.5O4 cells in order to scavenge and neutralize these decomposition products as well as soluble transition metal ions. This separator most probably prevents the migration of decomposition products to the anode and their subsequent reaction on the anode surface. Pouch cells with graphite anode, LiNi0.5Mn1.5O4 cathode, standard electrolyte and the Li4+x Ti5O12 based separator are cycled successfully for hundreds of cycles without any significant capacity fading. In contrast, similar cells equipped with a conventional separator show strong degradation.
An undivided zinc–cerium redox flow battery was studied under a wide range of operational conditions, including: (i) electrolyte composition; the concentrations of ([Zn2+], [Ce3+] and [H+]), (ii) current density (0–80mAcm−2), (iii) electrolyte flow linear velocity (0.64–7.0cms−1) and (iv) temperature (20–60°C). The charge efficiency increased at higher current densities and at higher electrolyte flow velocities. Unlike the divided zinc–cerium system, the charge–discharge performance decreased at higher temperature, since oxygen evolution became increasingly favored at the positive electrode. The use of a low acid concentration led to a poor conversion of Ce(III) to Ce(IV) ions during the discharge cycle. Mixed electrolytes containing methanesulfonate and sulfate anions have been evaluated at a high Ce(III) ion concentration, e.g. 0.4moldm−3. After charging the battery for 4h, the conversion of Ce(III) to Ce(IV) ions became less efficient over time due to a greater fraction of the current being used in oxygen evolution. Critical aspects for improvements in the battery performance are considered.
This manuscript reports on the development of a safe and green lithium-ion battery containing sodium salt of CarboxyMethylCellulose (CMC) as binder, lithium titanate (Li4Ti5O12) as anodic active material, lithium iron phosphate (LiFePO4) as cathodic active material and an electrolytic solution based on the ionic liquid N-butyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR14FSI). The battery showed, at room temperature, a very stable specific capacity of 140mAhg−1 constant for more than 150 cycles. This indicated that the introduction of low cost and environmentally benign binders, like CMC, and non-flammable electrolytes, such as PYR14FSI, represents a viable strategy for the development of new, greener and safer lithium-ion batteries.
Leptospirosis is a zoonotic disease that occurs all over the world, caused by bacteria of the genus Leptospira. Marsupial and didelphidae families are considered susceptible to infection caused by a wide range of Leptospira serovars for which they serve as reservoirs. Thirty-three free-living white-eared opossums (Didelphis albiventris) were captured in Southern Brazil and bodily fluids were collected. From the urine samples it was possible to obtain an isolate identified as Leptospira borgpetersenii by rpoB gene sequencing and belonging to serovar Castellonis by Multilocus Variable-Number Tandem-Repeat Analysis. This is the first report of the isolation of Leptospira spp. from the white-eared opossum in Brazil. In addition, the new strain was also virulent in the hamster model of lethal leptospirosis. The microscopic agglutination test (MAT) was used for detecting the presence of antibodies against Leptospira spp. in white-eared opossum, human, cattle and canine sera using a panel of 59 Leptospira strains that included the new isolate. The inclusion of the new strain in the MAT battery increased the MAT sensitivity for canine sera. These findings suggest that the white-eared opossum is an important reservoir of pathogenic Leptospira spp.
Neurocognitive assessment is an essential component for clinical trials of candidate “cognitive-enhancing” treatments for schizophrenia. However, manual administration of large, paper-based, neurocognitive batteries is often inefficient, error-prone, and inconsistent across multiple sites. Existing computerized testing systems are also limited both in the assessment instruments available and in the range of impairments that can be accommodated with the subject sitting alone at a single display. Therefore, a dual-display computerized testing system was developed, with funding from the National Institute of Mental Health (NIMH), that integrates (rather than replaces) the examiner for computerized administration of standard neurocognitive assessment batteries. Purpose To compare standard administration versions (SAVs) of tests selected by the NIMH-sponsored CATIE (Clinical Antipsychotic Trials of Intervention Effectiveness) and MATRICS™ (Measurement and Treatment Research to Improve Cognition in Schizophrenia) consortia, with structurally- and functionally-equivalent, computerized administration versions (CAVs). Method 116 outpatients with schizophrenia received both the SAVs and CAVs within one week and again, approximately 30 days later. Results Intraclass Correlation Coefficient (ICC) comparisons between SAVs and CAVs yielded highly significant measures of absolute agreement for all tests, ranging 0.61–0.95. ICCs for test–retest reliability, ranging 0.56–0.94 for SAVs and 0.59–0.98 for CAVs, were also highly significant for both batteries, though significantly higher for CAVs overall. Conclusions The CAVs of the neurocognitive assessment instruments selected by the CATIE and MATRICS™ consortia are substantially equivalent to antecedent SAVs. Importantly, the increased reliability afforded by computerization highlight the potential for increasing power, thereby decreasing sample size requirements, for clinical evaluations of putative “cognitive-enhancing” treatments.
The utilization of CO2 for the production of useful chemicals using heterogeneous catalysts is one of the ways to reduce the anthropogenic greenhouse gases in the atmosphere. In many cases, the CO2 conversion and products yield are still considered very low and need to be operated at high pressure and temperature. The critical point in CO2 conversion is to activate the CO2 molecules either by adding a co-reactant or by using effective catalysts. This paper presents the current development on the effect of several precursors like metals, metal oxides, ionic liquids, and acid–base loaded on a suitable support in creating magical properties of catalysts on the performance of CO2 conversion. Cu/ZnO-based catalysts, ionic liquid-based catalysts, and metal oxides-based catalysts are reported to be the most effective catalysts in the formation of methanol, cyclic carbonates and dimethyl carbonate. This review also focuses on various strategies and developments in altering heterogeneous catalysts, followed by critical factors of CO2 molecule activation, and the optimization of the catalytic activity or catalysts reusability.
The performance and cost of a bipolar plate cell design for a 40kWh lithium-air battery was estimated and compared to USABC goals. A bipolar plate cell design for a lithium-air battery can meet the cell performance goals, provided certain cell design targets are met. In particular, the excess lithium should be <2×, the current density should be >40mAcm−2, the cathode capacity should be >1650mAhg−1 carbon, and the bipolar plate material density should be <5gcm−3. Meeting the above targets, the specific and volumetric energy densities for the lithium-air cell were estimated at 640Whkg−1 and 600Whl−1, respectively; the specific and volumetric power densities were estimated at 1310Wkg−1 and 1220Wl−1, respectively. However, the system cost goal of $100kWh−1 for electric vehicles was not met; the cost of a 40kWh lithium-air battery system using a bipolar plate design was estimated at $238kWh−1.
Si has a very high theoretical capacity of 4200 mAh g−1 as the anode materials for lithium ion batteries, which is near ten times higher than that of the current commercial graphite anode. However, it suffers from severe volume expansion/contraction during the charge/discharge processes, which is the main obstacle for its application. In this work, we prepare Si/C composite anodes with an intercalated Si/C multilayer structure by alternately depositing C and Si by plasma decomposition of C2H2 and magnetron sputtering of a Si target, respectively. Near theoretical capacity can be achieved (about 4000 mAh g−1) for more than 100 cycles for thin Si layers, which is attributed to the buffer effect of the carbon layers. This structure is also scalable up to multiple Si/C layers. A critical thickness of 20 nm is found for the silicon layer, below which the near theoretical capacity can be stably maintained. This critical thickness may shed light on future designs of nanostructured silicon anode with high capacity and stability for lithium ion batteries.
The present communication deals with the leaching of gold and silver from the printed circuit boards (PCBs) of waste mobile phones using an effective and less hazardous system, i.e., a thiourea leaching process as an alternative to the conventional and toxic cyanide leaching of gold. The influence of particle size, thiourea and Fe3+ concentrations and temperature on the leaching of gold and silver from waste mobile phones was investigated. Gold extraction was found to be enhanced in a PCBs particle size of 100 mesh with the solutions containing 24g/L thiourea and Fe3+ concentration of 0.6% under the room temperature. In this case, about 90% of gold and 50% of silver were leached by the reaction of 2h. The obtained data will be useful for the development of processes for the recycling of gold and silver from the PCBs of waste mobile phones.
In this paper a novel technique for on-line estimation of impedance parameters of a battery equivalent circuit model (ECM) is presented. The ECM is often used as a basis of battery management algorithms to calculate the state of charge or the maximal available power. Especially the latter requires that the parameters of the ECM describe precisely the battery impedance. Unfortunately, the battery impedance changes over the battery lifetime due to aging. Therefore, the parameters of the ECM must be updated continuously. In this paper such an update is achieved using a novel approach that in addition allows considering current dependency of the battery impedance. The basic idea is that the change of the battery voltage under load is predicted using the ECM with different parameter sets during a short time period. The predicted voltage is then compared to the sensor data and the best parameter set is selected. It is then used as a basis in the next adaption step. A necessary strategy for building parameter sets is implemented for a fast and efficient convergence which results in an accurate parameter estimation. The algorithm runs on a standard 16 bit 80 MHz microcontroller at only 16% processor load.
Abstract Smart devices that can monitor a patient’s health with little or no intervention from clinical staff have begun to emerge over recent years and have arisen from advances in sensing and communication technologies. The integration of vital signs monitoring systems within phone/watch systems, in addition to a range of discrete wearable medical appliances, are the first of a new generation of connected health systems that will have considerable impact on future preventative screening measures. At present, the core rationale is a “detect-alert” sequence informing either the patient or a central clinic. In cases where a rapid response may be required, a much more effective alternative would be the development of a truly smart system that could autonomously act on the information received from the sensing component and, where appropriate, deliver a therapeutic agent in a controlled manner. While the sensing strategies may be entering a mature phase of development, the designs required for the actuation of an electronic controlled delivery are still in their relative infancy and represent a considerable scientific challenge. The aim of this review is to provide a critical overview of the latest developments in functional materials and nanoscale device architectures that can facilitate controlled reagent delivery.