batterydata/paper-abstracts huggingface dataset:
The genotoxicity of melamine was evaluated with the combined Pig-a mutation/micronucleus assay, the bacterial reverse mutation assay, and the in vitro cytokinesis-block micronucleus assay (CBMN). Five groups of six- to eight-week-old male Sprague–Dawley (SD) rats were given three daily doses of vehicle control (100% pure sesame oil), melamine (500, 1000, and 2000mg/kg) or positive control (N-ethyl-N-nitrosourea, ENU, 20mg/kg) by oral gavage. Peripheral blood was sampled pre-dose (day −1) and at time points up to day 60. Pig-a mutant frequencies were determined in total red blood cells (RBCs) and reticulocytes (RETs) as RBCCD59− and RETCD59− frequencies, on days −1, 15, 29 and 60, and micronucleus frequencies were measured in RETs on day 4. No significant increases in RBCCD59− or RETCD59− frequencies were observed for the melamine-treated group at any of the time points studied, but the positive control, ENU, induced statistically significant increases compared with the vehicle control. Similar results were obtained in the micronucleus assay. Melamine did not induce statistically significant increases in %MN-RET. In the bacterial reverse mutation assay, melamine was tested from 62.5 to 1000μg/plate in tester strains TA97a, TA98, TA100, TA102, and TA1535, with and without metabolic activation, and no evidence of toxicity or mutagenicity was observed at any dose tested. In the in vitro CBMN assay, in Chinese hamster ovary (CHO) cells, melamine was tested (75, 150, and 300μg/mL) in the presence and absence of S9 mix, and no positive increases in the number of cells containing micronuclei were seen. These results suggest that melamine does not exhibit significant genotoxic potential. These data could be valuable for risk assessment purposes and also for further characterizing the new in vivo Pig-a gene mutation assay.
Electrical equivalent circuit models demonstrate excellent adaptability and simplicity in predicting the electrical dynamic response of the all-vanadium redox flow battery (VRB) system. However, only a few publications that focus on this topic are available. The paper presents a comprehensive equivalent circuit model of VRB for system level analysis. The least square method is used to identify both steady-state and dynamic characteristics of VRB. The inherent features of the flow battery such as shunt current, ion diffusion and pumping energy consumption are also considered. The proposed model consists of an open-circuit voltage source, two parasitic shunt bypass circuits, a 1st order resistor-capacitor network and a hydraulic circuit model. Validated with experimental data, the proposed model demonstrates excellent accuracy. The mean-error of terminal voltage and pump consumption are 0.09 V and 0.49 W respectively. Based on the proposed model, self-discharge and system efficiency are studied. An optimal flow rate which maximizes the system efficiency is identified. Finally, the dynamic responses of the proposed VRB model under step current profiles are presented. Variables such as SOC and stack terminal voltage can be provided.
The present study is devoted to processing of scrap batteries and more particularly, to desulphurization of the battery pastes. The sulphate ions are removed from solution by a salting out processing potassium carbonate.
Spray drying and carbothermal method was employed to investigate reaction mechanism and electrochemical performance of LiFePO4/C cathode by using different carbon sources. Micro-structural variations of LiFePO4/C precursors using different carbon sources were studied by Thermo-gravimetric (TG)/Differential Thermal Analysis (DTA). The LiFePO4/C samples were characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) absorption spectroscopy. The results indicated that the crystallization temperature of LiFePO4 was 453°C, while the transform temperature was 539°C from Li3Fe2(PO4)3 to LiFePO4. At 840°C, LiFePO4/C sample with an excess of impurity phase Fe2P gave much poorer electrochemical performance. The severe decomposition of LiFePO4/C happened at 938°C and generated impurity phases Li4P2O7 and Fe2P. The clear discharge platform of Fe2P emerged at around 2.2V.
The paper summarises a literature review into waste management practices across Africa as part of a study to assess methods to reduce carbon emissions. Research shows that the average organic content for urban Municipal Solid Waste in Africa is around 56% and its degradation is a major contributor to greenhouse gas emissions. The paper concludes that the most practical and economic way to manage waste in the majority of urban communities in Africa and therefore reduce carbon emissions is to separate waste at collection points to remove dry recyclables by door to door collection, compost the remaining biogenic carbon waste in windrows, using the maturated compost as a substitute fertilizer and dispose the remaining fossil carbon waste in controlled landfills.
Publisher Summary One area where natural fibres have scope for consideration is the packaging industry. Packaging is the process of preparing an item for preservation, storage, transportation and display. The materials with which this is done depend on the category of packaging and the requirements of the item itself. Biodegradable polymers reinforced with natural fibres provide the next logical step in an effort to provide environmentally friendly cost-effective solutions for the packaging industry. The main goals for the use of natural fibres in packaging are to provide additional stiffness and strength, minimise weight and reduce cost by lowering polymer content. In addition, when combined with biodegradable polymers, natural fibres allow the biodegradability of the packaging material to be maintained. This chapter endeavours to identify the extent to which natural-fibre-based packaging is being utilised in the industry at present and the potential future applications. Plastics used for packaging are very often used once and then discarded, creating an unending waste stream. In the past, efforts to reduce this waste focused on either the use of natural fibres in non-biodegradable polymers or the use of biodegradable polymers. The importance of biodegradable polymers for sustainable development is paramount.
Guanxi, a type of particularistic trust observed in Confucian societies has mostly been viewed as a static phenomenon. It is not clear how the role of guanxi changes over time during institutional transitions. This field study of twenty one small and medium enterprises (SMEs) located in two large cities in Western China examines the changes in SME behaviors since the beginning of economic reforms in 1979. Based on neo-institutionalist trust perspectives, the article argues that the role of guanxi also arose from the paucity of market system trust created by the absence of well-established market institutions during China's transition from a centrally planned to a market economy. Guanxi became relatively less important when market system trust based on well-established institutions was firmly established. Regardless of past practices, the dynamics of institutional transitions leading to the establishment of system trust inevitably reshapes managerial as well as business behaviors, with adaptation occurring to the new rules of the market economy.
Publisher Summary This chapter describes digital video security and Internet transmission media with its unique modulation and demodulation requirements. The specific compression algorithms required to compress the video frame image file sizes to make them compatible with the existing wired and wireless transmission channels available are described. A powerful technology used to transmit the digital signal called spread spectrum modulation (SSM) has made wireless video transmission a reality. The 802.11 spread spectrum protocols are described as relating to video, voice, and command and control transmission. Security monitoring is no longer limited to local security rooms and security officers, but rather extends out to remote sites and personnel located anywhere around the world. Monitoring equipment includes flat panel displays, personal computers (PCs), laptops, personal digital assistants (PDAs), and cell phones. The requirement for individual personnel to monitor multiple display monitors has changed to a technology of incorporating smart cameras with video motion detectors (VMDs) to establish an automated video surveillance (AVS) system from local and remote sites.
Gel polymer electrolytes composed of poly(vinylidene fluoride-hexafluoropropylene) copolymer, poly(vinylidene fluoride) polymer, PC+DEC as plasticizer and LiClO4 as salt have been synthesized by solvent casting technique with varying the plasticizer-salt concentration ratio systematically. Complex impedance spectroscopy has been carried out to investigate ionic conduction in P(VDF-HFP)–(PC+DEC)–LiClO4 and PVDF–(PC+DEC)–LiClO4 electrolyte systems. Transport number measurements have been made by Wagner’s polarization technique. With all other parameters same, P(VDF-HFP) electrolytes exhibit higher ionic conductivity and transport number as compared to PVDF based electrolytes which could be attributed to higher degree of amorphicity in the P(VDF-HFP) system. XRD and FTIR studies have been conducted to investigate the structural and complexation in the polymer gel electrolytes. Microstructural studies by SEM exhibit higher amorphicity and solvent retention capability for P(VDF-HFP)–(PC+DEC)–LiClO4 system than those of PVDF–(PC+DEC)–LiClO4 system.
In addition to regulating sex, size, and season of harvest, resource managers can implement spatial fishery closures as a management tool to protect Dungeness crab populations. Yet, we have little understanding of the role that spatial closures play in conserving crab populations, especially in fisheries management zones that are subject to intensive harvest. The primary purpose of this study was to evaluate the biological effectiveness of a crab closure area adjacent to an intensive fishery, by examining relative abundance, population demographics, and seasonal movement patterns within and outside of a closure area. Relative abundance and population demographics were assessed weekly from August to October, using standardized trap lines distributed at four locations, stratified by treatment (inside versus outside of closure area) and water depth. To obtain individual male crab movement data within and outside of the closure area, mobile acoustic tracking surveys were conducted one to three times per week in the autumn and winter. Male crabs were larger and in greater abundance inside the closure area than outside. The overall trend in male crab movement was southwest towards deeper water during autumn and winter. Our research supports the hypothesis that fisheries decrease the abundance and size of an exploited species, but closure areas may reduce these effects. Based on the observed seasonal movement patterns of crabs, it appeared that the closure area provided a temporary refuge from harvest. Resource managers should consider seasonal movement patterns, habitat use, and quality of available habitat when selecting closure area boundaries.
The hydrothermal reaction of Cu(II) salt, ammonium heptamolybdate and 4-ptz (5-(4-pyridyl) tetrazole) at different synthetic conditions yields two compounds [Cu(4-Hptz)(Mo2O7)] (1) and [Cu(4-Hptz)2(H2O)3]2[Mo8O26] (2). Both the compounds 1 and 2 are characterized by routine elemental analyses, IR-, thermogravimetric studies and unambiguously characterized by single crystal X-ray crystallography. Compound 1 exhibits a 3D bimetallic oxide framework, constructed from the tetrazoles and {CuMo2O7} oxide phase. The coordination ability of nitrogen atoms in the tetrazole ring makes the ring acting as a template in the formation of {Cu4Mo6O10} rings, made up of [Mo2O7]2− anions and Cu(II) octahedra; the stacking of these {Cu4Mo6O10} rings along crystallographic c axis results in the formation of 3D bimetallic oxide framework. Compound 2 consists of infinite octamolybdate chains and Cu–tetrazolate complex cation. The formation of oxide phase under hydrothermal conditions is discussed, giving importance of the role of geometry of the tetrazole ring.
LiFePO4/C was prepared by solid-state reaction from Li3PO4, Fe3(PO4)2·8H2O, carbon and glucose in a few minutes in a scientific MW (microwave) oven with temperature and power control. The material was characterized by X-ray diffraction, scanning electron microscopy and by TGA analysis to evaluate carbon content. The electrochemical characterization as positive electrode in EC (ethylene carbonate)–DMC (dimethylcarbonate) 1M LiPF6 was performed by galvanostatic charge–discharge cycles at C/10 to evaluate specific capacity and by sequences of 10s discharge–charge pulses, at different high C-rates (5–45C) to evaluate pulse-specific power in simulate operative conditions for full-HEV application. The maximum pulse-specific power and, particularly, pulse efficiency values are quite high and make MW synthesis a very promising route for mass production of LiFePO4/C for full-HEV batteries at low energy costs.
Strong motivation for developing new prosthetic hand devices is provided by the fact that low functionality and controllability—in addition to poor cosmetic appearance—are the most important reasons why amputees do not regularly use their prosthetic hands. This paper presents the design of the CyberHand, a cybernetic anthropomorphic hand intended to provide amputees with functional hand replacement. Its design was bio-inspired in terms of its modular architecture, its physical appearance, kinematics, sensorization, and actuation, and its multilevel control system. Its underactuated mechanisms allow separate control of each digit as well as thumb–finger opposition and, accordingly, can generate a multitude of grasps. Its sensory system was designed to provide proprioceptive information as well as to emulate fundamental functional properties of human tactile mechanoreceptors of specific importance for grasp-and-hold tasks. The CyberHand control system presumes just a few efferent and afferent channels and was divided in two main layers: a high-level control that interprets the user’s intention (grasp selection and required force level) and can provide pertinent sensory feedback and a low-level control responsible for actuating specific grasps and applying the desired total force by taking advantage of the intelligent mechanics. The grasps made available by the high-level controller include those fundamental for activities of daily living: cylindrical, spherical, tridigital (tripod), and lateral grasps. The modular and flexible design of the CyberHand makes it suitable for incremental development of sensorization, interfacing, and control strategies and, as such, it will be a useful tool not only for clinical research but also for addressing neuroscientific hypotheses regarding sensorimotor control.
To achieve a high energy density for Li-ion batteries, it is important to optimize the electrode thickness and electrode density. It is common to design the electrodes to be thick and dense to achieve a high energy density. However, highly tortuous transport paths in thick and dense electrodes can lead to severe transport losses, which negatively affect the cell performance. In this work, we investigated the effects of varying the electrode thickness and density on lithium ion transport in the electrolytes by means of both experiments and simulations. Both results indicated that an additional capacity loss occurs from the electrode with low porosity because the effective diffusivity decreased in the electrolyte phase. Optimal ranges of the electrode thickness and density (porosity) that can be used to help design high-power LiFePO4/graphite batteries were also suggested in this work.
Vanadium redox flow batteries (VRFBs) are attracting increasing amounts of attention for energy storage applications. However, their electrochemical performance capabilities have not been closely analyzed because proper reference electrodes remain elusive. In this work, we report the resistor design of a dynamic hydrogen electrode (DHE) for VRFBs which enables the in-situ monitoring of the positive and negative electrode potential. Due to the presence of multiple redox couples at the reference electrode inserted into the VRFB membrane, the adjustment of the current flowing through the DHE with the resistor is the key factor when attempting to maintain a stable and steady hydrogen reduction reaction at the DHE during repeated charge and discharge processes. With the insertion of the DHE into the membrane, the electrochemical properties of the positive and negative electrode/electrolyte can be individually analyzed. Thus, the DHE design provides an effective electrochemical analysis platform for VRFB research.
A lithium polyacrylate (Li-PAA) binder has been developed by 3M Company that is useful with electrodes comprising alloy anode materials. This binder was used to prepare electrodes made with Sn30Co30C40 material prepared by mechanical attrition. The electrochemical performance of electrodes using Li-PAA binder was characterized and compared to those using sodium carboxymethyl cellulose (CMC) and polyvinylidene fluoride (PVDF) binders. The Sn30Co30C40 electrodes using Li-PAA and CMC binders show much smaller irreversible capacity than the ones using PVDF binder. Poor capacity retention is observed when PVDF binder is used. By contrast, the electrodes using Li-PAA binder show excellent capacity retention for Sn30Co30C40 materials and a specific capacity of 450mAh/g is achieved for at least 100 cycles. The results suggest that Li-PAA is a promising binder for electrodes made from large-volume change alloy materials.
The redox flow battery (RFB) is among the most promising large-scale energy storage technologies for intermittent renewables, but its cost and cycle life still remain challenging for commercialization. This work proposes and demonstrates a high-performance, low-cost and long-life tin-bromine redox flow battery (Sn/Br RFB) with the Br-mixed electrolyte. The coulombic efficiency and energy efficiency of the Sn/Br RFB reach 97.6% and 82.6% at a high operating current density of 200 mA cm−2, respectively. The peak power density at 50% state-of-charge achieves 673 and 824 mW cm−2 at 15 and 35 °C, respectively, which is among the highest performance of hybrid RFBs. To address the Sn cross-contamination issue, a Sn reverse-electrodeposition method is demonstrated, and achieves in-situ capacity recovery as well as long cycle life. Moreover, the active material cost of the Br-mixed electrolyte is merely $54 kWh−1, while capital cost of the Sn/Br RFB is estimated to be as low as $193 kWh−1 for 4-hour electricity discharge, and expected to reduce to $148 kWh−1 at the optimistic scenario in the future. With high cell performance, in-situ capacity recovery and inexpensive active materials, the Sn/Br RFB is believed to offer a promising solution for massive electricity storage.
The exploration of cheap and stable electrocatalysts with high activity towards oxygen reduction reaction in the acidic and alkaline medium is a vital activity for large-scale applications of fuel cells. In recent years, one-dimensional nanofibrous electrode materials with high surface area and specific porosities have been drawing great attention in energy conversion devices such as fuel cells and metal-air batteries. Nanofibers with a one-dimensional nanostructure can be produced by electrospinning, which has been considered as a particularly low-cost and versatile method. In this review, we summarize the properties of electrospun nanofibers and the recent progress in designing of non-precious nanostructured electrocatalysts for oxygen reduction reaction in fuel cells. More importantly, we also highlight the interesting nanostructures, new synthetic approaches, and the electrocatalytic performance including active sites and stability of electrospun-based electrocatalysts. In addition, we describe the research challenges and future developmental perspectives of electrospun materials in energy technology.
Calcium-ion intercalation-based batteries receive attention as one type of post lithium-ion battery because of their potential advantages in terms of cost and capacity. A birnessite-type manganese oxide, K0.31MnO2·0.25H2O, is characterized by a layered structure with interlayer distances of ∼7 Å. Here, we demonstrate for the first time the electrochemical Ca2+ ion intercalation capability of K-bir, and elucidate the calcium-ion storage mechanism. A reversible electrochemical reaction is observed in cyclic voltammograms and galvanostatic cycles. The initial specific discharge capacity is 153 mAh g−1 at 25.8 mA g−1 (0.1 C) in a 1 M Ca(NO3)2 aqueous electrolyte, with the average discharge voltage of 2.8 V (vs. Ca/Ca2+). X-ray diffraction, transmission electron microscopy, and elemental analyses confirm that Ca2+ ion transport is mainly responsible for the electrochemical reaction. A kinetic analysis using CVs with various scan rates indicates that the reaction mechanism can be described as a combined reaction of a surface-limited capacitance and a diffusion-controlled intercalation. In addition, 3D bond valence sum difference maps show the 2D network for conduction pathways of calcium ions in the structure. This work demonstrates that birnessite-type manganese oxide could be a potential cathode material for calcium-ion batteries.
Existence of defects is an inherent property of real materials. Due to an explicit correlation between defects concentration and conductivity, it is important to understand the level and origins of the structural heterogeneity for any particulate electrode material. Poor conductive lithium titanate Li4Ti5O12 (LTO), widely used in batteries for grids and electric buses, needs it like no one else. In this work, structural heterogeneity of compacted lithium titanate is measured locally in 100 different points by conventional micro-Raman technique, characterized in terms of variation of Raman spectra parameters and interpreted using our version of “big data” analysis. This very simple approach with automated measurement and treatment has allowed us to demonstrate inherent heterogeneity of solid-state synthesized LTO and attribute it to the existence of lithium and oxygen vacancies. The proposed approach can be used as a fast, convenient, and cost-effective defects-probing tool for a wide range of materials with defects-sensitive properties. In case of LTO, such an approach can be used to increase its charge/discharge rates by synthesis of materials with controlled nonstoichiometry. New approaches to solid state synthesis of LTO, suitable for high-power applications, will help to significantly reduce the costs of batteries for heavy-duty electric vehicles and smart-grids.