batterydata/paper-abstracts huggingface dataset:
Perisomatic GABAergic synapses onto hippocampal pyramidal cells arise from two populations of basket cells with different neurochemical and functional properties. The presence of the dystrophin–glycoprotein complex in their postsynaptic density (PSD) distinguishes perisomatic synapses from GABAergic synapses on dendrites and the axon-initial segment. Targeted deletion of neuroligin 2 (NL2), a transmembrane protein interacting with presynaptic neurexin, has been reported to disrupt postsynaptic clustering of GABAA receptors (GABAAR) and their anchoring protein, gephyrin, at perisomatic synapses. In contrast, targeted deletion of Gabra2 disrupts perisomatic clustering of gephyrin, but not of α1-GABAAR, NL2, or dystrophin/dystroglycan. Unexpectedly, conditional deletion of Dag1, encoding dystroglycan, selectively prevents the formation of perisomatic GABAergic synapses from basket cells expressing cholecystokinin. Collectively, these observations suggest that multiple mechanisms regulate formation and molecular composition of the GABAergic PSD at perisomatic synapses. Here, we further explored this issue by investigating the effect of targeted deletion of Gabra1 and NL2 on the dystrophin–glycoprotein complex and on perisomatic synapse formation, using immunofluorescence analysis with a battery of GABAergic pre- and postsynaptic markers. We show that the absence of α1-GABAAR increases GABAergic synapses containing the α2 subunit, without affecting the clustering of dystrophin and NL2; in contrast, the absence of NL2 produces highly variable effects postsynaptically, not restricted to perisomatic synapses and being more severe for the GABAAR subunits and gephyrin than dystrophin. Altogether, the results confirm the importance of NL2 as organizer of the GABAergic PSD and unravel distinct roles for α1- and α2-GABAARs in the formation of GABAergic circuits in close interaction with the dystrophin–glycoprotein complex.
This review paper summarizes the existing knowledge on the chemical hazards associated with recycling and other end-of-life treatment options of waste electrical and electronic equipment (e-waste). The hazards arise from the presence of heavy metals (e.g., mercury, cadmium, lead, etc.), flame retardants (e.g., pentabromophenol, polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol-A (TBBPA), etc.) and other potentially harmful substances in e-waste. If improperly managed, the substances may pose significant human and environmental health risks. The review describes the potentially hazardous content of e-waste, examines the existing e-waste management practices and presents scientific data on human exposure to chemicals, workplace and environmental pollution associated with the three major e-waste management options, i.e., recycling, incineration and landfilling. The existing e-waste management practices and associated hazards are reviewed separately for developed and developing countries. Finally, based on this review, the paper identifies gaps in the existing knowledge and makes some recommendations for future research.
The effect of Fe concentration on the Fe-induced self-discharge of electrochemical capacitor carbon electrodes in aqueous H2SO4 is presented. With an Fe-free system, the positive electrode self-discharges via an activation controlled self-discharge mechanism, while the negative electrode self-discharges with a diffusion control profile. This highlights that the self-discharge mechanism on each electrode of an electrochemical capacitor is likely different, and should be examined in a three-electrode (half cell) setup. It is shown that Fe concentrations up to 10−5 M can be tolerated with no enhancement of self-discharge on the positive electrode. Whereas the negative carbon electrode can withstand Fe concentrations of 10−3 M without self-discharge increase. Additionally, it is shown that the diffusion controlled Fe-induced self-discharge (at concentrations at and above 10−4 M on the positive electrode) occurs primarily on the external surface of the porous electrode, and the carbon surface inside the pores does not participate in self-discharge. This is used to explain why the Conway diffusion model for self-discharge, derived for semi-infinite diffusion to a planar electrode, can be used to fit the self-discharge process on porous electrodes.
The recently released report of the International Energy Outlook (IEO2009) projects an increase of 44% in the world energy demand from 2006 to 2030, and 77% rise in the net electricity generation worldwide in the same period. However, threatening in the said report is that 80% of the total generation in 2030 would be produced from fossil fuels. This global dependence on fossil fuels is dangerous to our environment in terms of their emissions unless specific policies and measures are put in place. Nevertheless, recent research reveals that a reduction in the emissions of these gases is possible with widespread adoption of distributed generation (DG) technologies that feed on renewable energy sources, in the generation of electric power. This paper gives a detailed overview of distributed energy resources technologies, and also discusses the devastating impacts of the conventional power plants feeding on fossil fuels to our environment. The study finally justifies how DG technologies could substantially reduce greenhouse gas emissions when fully adopted; hence, reducing the public concerns over human health risks caused by the conventional method of electricity generation.
Hierarchical MoO2/N-doped carbon heteronanowires (MoO2/N-C H-NWs) are synthesised by simple calcination using organic–inorganic hybrid nanowires as a precursor and self-template. In the heterostructure, MoO2 nanoparticles are not only anchored on but also embedded in the one-dimensional N-doped carbon matrix. The synergistic effect promotes the pseudocapacitance, decreases the charge transfer resistance, and buffers the volume change on the reaction of MoO2/N-C H-NWs with Li+. Therefore it endows the composite with enhanced kinetics and stability for reversible Li+ storage. At a current density of 2 A g−1, the MoO2/N-C H-NWs deliver a reversible capacity of 700 mAh g−1 after 400 cycles, which still remains 570 mAh g−1 even after 1500 cycles. The high capability suggests that the MoO2/N-C H-NWs may be a promising candidate for use as anode material in high-performance lithium-ion batteries.
In this work, LiFePO4/C composites were prepared in hydrothermal system by using iron gluconate as iron source, and two feeding sequences during the preparation were comparatively studied. The morphology, crystal structure and charge–discharge performance of the prepared samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and galvanostatic charge–discharge testing. The results showed that the feeding sequences and iron gluconate seriously affected the microstructures and electrochemical properties of the resulting LiFePO4 cathodes in lithium ion batteries. The spindle-shaped LiFePO4 with hierarchical microporous structure self-assembled by nanoparticles has been successfully synthesized by synthesis route B. In addition, the cell performance of the synthesized LiFePO4 by synthesis route B was better than that of LiFePO4 by synthesis route A. Specially at high rates, the superior rate performance of the spindle-shaped LiFePO4/C microstructure (LFP/C-B) was revealed. And special reversible capacities of ∼118 and ∼95mAhg−1 were obtained at rates of 2C and 5C, comparing to ∼96 and ∼68mAhg−1 for LFP/C-A.
We report here a detailed impedance analysis of the interface between a selected IL electrolyte, i.e. a solution of lithium N,N-bis(trifluoromethane sulfon) imide in N-n-butyl-N-ethyl pyrrolidinium and a N,N-bis(trifluoromethane sulfon) imide, LiTFSI-Py24TFSI, and two electrodes, namely a conventional lithium metal and an advanced nanostructured Sn–C alloy, respectively. We show that the Sn–C alloy, in virtue of a specific formation of a surface protecting film, has an interface much more stable than that of the Li electrode. This favourable property is exploited for using Sn–C as a new anode for the development of an advanced lithium-ion battery based on LiTFSI-Py24TFSI as the electrolyte and on olivine LiFePO4 as the cathode. The results demonstrated that this battery has very promising performances in terms of cycle life and rate capability.
Hollow nanospheres of mesoporous Co9S8 are successfully synthesized by a facile solvothermal reaction followed with a high-temperature annealing in Ar/H2. These hollow nanoparticles exhibit a reversible capacity of ~1414mAhg−1 after 100 cycles at 100mAg−1. In the course of this cycling, there is a significant capacity recovery, which is associated with enhanced capacitance caused by repeated electro-chemical milling. The growth of a carbon shell on the hollow nanospheres further improves the reversible capacities at high rates, ~896mAhg−1 after 800 cycles at 2Ag−1. The excellent lithium-storage performances shed light on the promising potential of sulfides as a high capacity, high rate and long life anodes.
Anatase FCNTs (functionalized carbon nanotubes)-wired TiO2 nanocomposites have been successfully synthesized via a facile one-pot hydrothermal method. The prepared composites are composed of uniform nanoparticles of TiO2 intimately interconnected by FCNTs networks. FCNTs-wired TiO2 nanocomposites display improved electrochemical performance than bare TiO2, especially for high rate capability. FCNTs-wired TiO2 nanocomposite with 2 wt% functionalized carbon nanotubes shows optimized electrochemical performance. It exhibits high initial discharge capacity (109.2 mAh g−1) with almost no capacity fading after 100 cycles at a super-high current density of 5040mAg−1 (30C). The tightly bound structure with FCNTs could enhance electronic conductivity, decrease the charge transfer resistance, and increase the lithium diffusion coefficient, thus improving rate capability of TiO2 remarkably. All these results demonstrate that FCNTs-wired TiO2 nanocomposites with super rate capability and excellent cycling performance have a promising application as anode materials for lithium ion batteries.
β-FeOOH prepared with an enhanced hydrolysis method had been subjected to H+/Li+ exchange with various lithium salts in ethanol for various duration. The effects of the kind of lithium salt used and the duration of ionic exchange on the composition, the crystalline structure, and the electrochemical properties of the prepared powders were investigated. It was found that α-LiFeO2 can be prepared from β-FeOOH by an ionic exchange reaction with LiOH in ethanol at 85°C. α-LiFeO2 powders so prepared show electrochemical active properties with reversible capacity of 65–80mAhg−1. The in situ XRD patterns of the cycled α-LiFeO2 cathode revealed that the crystalline structure remains unchanged while the lattice of cubic decreases and increases periodically upon charge/discharge cycling. The results of XANES suggest that the electrochemical reaction of the Fe3+/Fe2+ redox couple occurs as the prepared α-LiFeO2 electrode is charge/discharge cycled.
A novel aqueous lithium–air rechargeable cell with the configuration of Si/1 M LiClO4 in ethylene carbonate–diethylene carbonate/Li1+x+y Al x (Ti,Ge)2−x P3−y Si y O12/5 M LiCl–1 M LiOH aqueous solution/carbon black, air is proposed. A silicon anode composed of mechanically milled silicon power with an average particle size of ca. 0.5 μm, vapor grown carbon fiber and a polyimide binder was examined. The open-circuit voltage at the charged state was 2.9 V at 25 °C. The discharge capacity of 700 mAh g-silicon−1 was retained for 40 cycles at 0.3 mA cm−2 with cut-off voltages of 3.5 and 1.5 V. Significant capacity fade was observed at deep charge and discharge cycling at 2000 mAh g-silicon−1.
The objective of this work is to improve the performance of the positive electrode of lead-acid battery. The use of the additive in the positive paste is to increase the capacity and cycle life of the positive active material. Mineral porous additives, dispersed uniformly in the PAM, may act as acid reservoirs and favor the ionic diffusion. The results show that the addition of mineral additive in the paste before oxidation influences the composition and the crystal size of the PAM after oxidation. We observe a remarkable improvement of the discharge capacity of the PAM for an amount of additive ranging between 1 and 5%. Nano-sized particles of PbO2 with amorphous character are obtained. XRD, TG and DSC, SEM, and galvanostatic discharge were used as techniques of investigation.
The heartbeat originates within the sinoatrial node (SA node or SAN), a small highly specialized structure containing <10,000 genuine pacemaker cells. The ~5 billion working cardiomyocytes downstream of the SAN remain quiescent when it fails, leading to circulatory collapse and fueling a $6B/year electronic pacemaker industry. The electronic pacemaker devices work quite well. But, device-related problems persist. These include lead failure/repositioning, finite battery life, and infection. For pediatric patients, the children outgrow the length of the leads, necessitating replacement with longer leads. These pitfalls have motivated creation of biological pacing. that are free from all hardware. Toward this goal, we and others have tested the concept of biological pacemakers. Combined with efforts to create clinically relevant, large animal models of biological pacing, the field is moving beyond a conceptual novelty toward a future with clinical reality.
The electrochemical impedance spectroscopic (EIS) responses of polyaniline (PANI)-coated graphite electrodes are governed by the process occurring at the PANI∣electrolyte interface and the bulk faradaic redox transitions within the conducting polymer in the high-frequency and low-frequency regions, respectively. The redox transitions between the different oxidation structures of PANI cause the polymer to behave as a pseudocapacitor, especially at potentials ≥200 mV. A combination of the respective equivalent circuits for the electrode completely coated with a PANI film and for a bare graphite substrate successfully represents the EIS spectra of the electrodes with partial coverage of the polymer. A comparison of the EIS and chronopotentiometric results reveals that the effects of the anions on the electrochemical behavior of PANI are more obviously illustrated by the EIS method.
Direct synthesis of dimethyl carbonate offers prospects for a “green chemistry” replacement of phosgene use for polymer production and other processes. The carbonylation of methanol to produce dimethyl carbonate over a Cu+X zeolite prepared by solid-state ion exchange has been investigated in a flow system at temperatures between 100 and 140 °C and a total pressure of 1 atm. Formation rates of dimethyl carbonate, methylal, and methyl formate are well described by a Langmuirian reaction mechanism, with quasi-equilibrated adsorption of methanol and oxidation of surface methanol to form methoxide, rate-limiting carbon monoxide insertion into the methoxide to form a carbomethoxide, and reaction of carbomethoxide with methoxide to form dimethyl carbonate. The by-products (methylal and methyl formate) are products of partial oxidation of the methoxide to formaldehyde. In situ FTIR experiments show the surface species present on the catalyst under reaction conditions and the effect of water on the system.
We introduce a “gelating-cutting” strategy to improve specific areal capacity and cycle life for Li-O2 cathode. Conventional Li-O2 cathode with liquid electrolyte is gelated with highly elastic crosslinked polymer and cut into 50–200 µm granules. The gaps between the packed gel granules efficiently induce oxygen to the inner part of the cathode, leading to even Li2O2 growth in thick cathode. Meanwhile, the elasticity of the polymer chain helps to keep good contact between carbon and Li2O2 nanoparticles, which facilitates the electron transfer and improves the cyclability. Without any catalyst, the granular gel cathode is able to run 170 cycles at a fixed capacity of 1000 mA h gcarbon −1, or maintains a specific capacity higher than 10,500 mA h gcarbon −1 (12.6 mA h cm−2) during 11 cycles of full discharge-charge. Since good contact is the precondition to any electrochemical reaction, our strategy is a general way to enhance the performance of Li-O2 cathodes.
By union of graphitic carbon nitride polymer with reduced graphene oxide (rGO, ≤1 wt%) via π–π stacking interaction, the band structure of carbon nitride could be well modulated. As a result, a significant increase of photocurrent was observed (e.g., when biased at 0.4 V vs.Ag/AgCl, the anodic photocurrent became 300% higher after doping). Not merely interesting in itself, graphene was also used as a general dopant for semiconductors in band-structure engineering.
The home energy management problem has many different facets, including economic viability, data uncertainty and quality of strategy employed. The existing literature in this area focuses on individual aspects of this problem without a detailed, holistic analysis of the results with regards to practicality in implementation. In this paper, we fill this gap by performing a comprehensive comparison of seven different energy management strategies, each with different levels of practicality, sophistication and computational requirements. We analyse the results in the context of these three characteristics, and also critique the modelling assumptions made by each strategy. Our analysis finds that using a more sophisticated energy management strategy may not necessarily improve the performance and economic viability of the PV-battery system due to the effects of modelling assumptions, such as the treatment of uncertainties in the input data and battery degradation effects.
Polarization studies have indicated occurrence of three reactions on the cathode surface during precipitation of nickel hydroxide. Out of the three reactions, the nitrite forming reaction followed by conversion to ammonium ion might be the reaction path. The reaction scheme is well supported by the trends in variations in open-circuit potential. Detail prolonged galvanostatic precipitation studies have shown that (OH)−/Ni2+ ratio plays an important role in determining the phase of the nickel hydroxide. A ratio of (OH)−/Ni2+ higher than 6 with sufficient nickel ion in bath ensures β-nickel hydroxide with bigger particles and lesser H2O molecules within. Maintaining these ratios at lesser levels forms α-nickel hydroxide with finer size and more H2O molecules within. The mechanism of these products formations has been explained in this paper. It is also observed that finer size with higher surface area and higher H2O molecules in crystal structure results in higher discharge capacity.
LiFePO4 has emerged as the winning cathode material for a new generation of Li-ion batteries that are increasingly used for hybrid and electric vehicles, due to its remarkable electrochemical properties. The present review gives the state of the art in the understanding of the properties of this material and the other members of the same family. We discuss the effects of the decrease of the size of the particles down to circa 20 nm; some of them have been misunderstood or are still open questions. All of them are important to determine the trends in the research and development on this family of materials in the future. The cells' properties are also reviewed with both the graphite and more recently the Li4Ti5O12 anodes, the last one providing outstanding performance in terms of cycling life and power that make them promising not only for electric vehicles, but also to solve for intermittence locally in smart grids.
In this paper, a flexible DC load to test and evaluate current–voltage characteristics of fuel cells stacks and photovoltaic modules based on DC–DC converters is proposed. The load features are simple structure, scalability, low cost, and its possibility to emulate an arbitrary load profile. The measure of the desired characteristics of fuel cells and photovoltaic modules further includes high speed of response and high fidelity. A comparison between conventional methods and the proposed one is also provided. Experimental results show the usefulness of the DC load proposed.
The performance of lithium batteries degrades over time. The degradation rate strongly depends on stress conditions during use and even at rest. Thus, accurate and rapid diagnosis of battery state of health (SOH) is necessary for electric vehicle manufacturers to manage their vehicle fleets and warranties. This paper demonstrates a simple method for assessing SOH related to battery energy capability (SOHE). The presented method is based on the monitoring of Urelax over aging. Urelax is the open-circuit voltage of the battery measured after full charging and 30min of rest. A linear dependence between Urelax and remaining capacity is noted. This correlation is demonstrated for three different commercial battery technologies (different chemistries) aged under different calendar and power cycling aging conditions. It was determined that the difference between two Urelax voltages measured at two different aging states is proportional to SOHE decay. The mean error of the linear model is less than 2% for certain cases. This method could also be a highly useful and rapid tool for a complete battery pack diagnosis.
In this paper, via adjusting Mg content in Pr3−x Mg x Ni9 (x =0.45−1.2) alloys, a PuNi3-type single-phase Pr2MgNi9 alloy was obtained by powder-sintering method. The solid solubility of Mg in PuNi3-type phase and phase transformation of Pr3−x Mg x Ni9 (x =0.45−1.2) alloys at 1173K sintering temperature, as well as hydrogen storage properties of single-phase RE2MgNi9 (RE=La, Pr, Nd) alloys were subsequently studied. We found that when x increased from 0.45 to 1.0, entrance of Mg into Pr2 sites of PuNi3-type phase resulted in a phase transformation from Gd2Co7-type to PuNi3-type, reaching the maximum solid solubility at x =1.0 with a PuNi3-type single phase at 1173K. As x further increased to 1.2, an MgCu4Sn-type secondary phase formed. That was the phase transformation occurs to increase the super-stacking phase possessing more [A2B4] slabs with increase of Mg content. Electrochemical results showed that single-phase alloy had good discharge capacity and superior cycling stability. Comparing with PuNi3-type single-phase La2MgNi9 and Nd2MgNi9 alloys, PuNi3-type single-phase Pr2MgNi9 alloy also exhibited preferable cycling stability and high rate dischargeability (HRD), which were 86.3% (at 100 cycles) and 56.7% (at a current density of 1500mAg−1), respectively.
A fuel cell operating with aqueous sodium borohydride and hydrogen peroxide streams, with one, two and four cells (electrode area 64, 128 and 256cm2) connected in a bipolar mode in a filterpress flow cell is reported. The oxidation of borohydride ion was carried out on Au/C particles supported on a carbon felt electrode while the reduction of hydrogen peroxide was carried out on carbon supported Pt on a carbon paper substrate. Comparable cell potentials and power densities to direct borohydride fuel cells reported in the literature were obtained. The challenges to further development includes: increasing the low current density and avoid decomposition of borohydride and peroxide ions. The maximum power obtained at 20°C for one, two and four cell stacks was 2.2, 3.2 and 9.6W (34.4, 25 and 37.5mWcm−2, respectively) with cell voltages of 1.06, 0.81 and 3.2V at current densities of 32, 16 and 12mAcm−2, respectively.