batterydata/paper-abstracts huggingface dataset:
For the first time, self-assembled CoS2 nanoparticles wrapped by CoS2-quantum-dots anchored graphene nanosheets (CoS2NP@G-CoS2QD) are synthesized by a facile l-cysteine-assisted hydrothermal reaction. When the composite is used as anode in lithium-ion batteries (LIBs), it shows superior electrochemical performance: the reversible specific capacity is as large as 1048mAhg−1; the 300th-cycle capacity still maintains 831mAhg−1 even at 1Ag−1; the rate capacity remains 411mAhg−1 even at 10Ag−1, which is the highest value ever reported at such high current density for CoS2 based materials. The excellent electrochemical performance is attributed to the unique structure with CoS2 nanoparticles homogeneously wrapped by highly flexible and conductive few-layer graphene nanosheets adhering abundant CoS2 quantum dots, which can effectively suppress the aggregation of CoS2 nanoparticles, accommodate the volume change during the cycle processes and maintain high electrical conductivity of the electrode. The CoS2NP@G-CoS2QD composite is promising for superior-capability anode for LIBs and can be further extended to broad applications in supercapacitors, sensors, and catalysis.
In order to make optimal long-term care-related decisions, it is important to take a societal perspective. Shanghai is one of the pilot cities of social long-term care insurance in China. However, little knowledge exists about the economic value of the informal care provided to dependent elderly people in China. This paper aims to evaluate the economic value of informal caregiving in Shanghai using the contingent valuation method by their least-preferred care tasks, and identify the associated factors of willingness-to-pay (WTP) and willingness-to-accept (WTA) of the informal caregivers.
We have recently reported the reversible sodium intercalation in β-VOPO4 that has a moderate-high discharge plateau at 3.3 V vs. Na/Na+ and a theoretical capacity of 166 mAh g−1. However, the practical applications of the cathodes are still impeded by the low electrical and ionic conductivities as seen in many metal polyanion cathodes. Herein, VOPO4/C and NaVOPO4/C composites have been prepared by ball-milling and tested in sodium ion batteries. X-ray diffraction and scanning electron microscopy confirm the phase is maintained after the ball-milling process, while the particle size is obviously reduced. Electrochemical tests show much improved capacities of 85 mAh g−1 (∼0.5 Na-ions per formula) at C/20. At a higher temperature of 45 °C, the discharge capacities are further increased to 130 mAh g−1 and 115 mAh g−1 for VOPO4/C and NaVOPO4/C (∼0.78 Na-ions per formula for either) along with long-term cycling. The preliminary results suggest β-VOPO4 has the potential to exhibit good practical performance upon structural optimization. Thus, the exploration on the fabrication of nanoparticles and more efficient conductive coating will probably lead to more fruitful achievements.
The electrochemical lithiation/delithiation processes of InAs nanowires (NWs) are studied by in-situ transmission electron microscopy. Our results indicate that InAs NWs have a fast lithiation speed of 275nm/s and a high lithium ion (Li-ion) diffusion coefficient of 2.49×10−8 cm2/s at room temperature. Upon lithiation, the Li-ion insertion firstly results in severe lattice distortions of InAs NWs, and the formation of Li3As and Li x In through the conversion and alloying processes take place on further lithiation. A small volume expansion of 157% is observed in full lithiation and is attributed to the naturally formed surface oxide layer. During the delithiation process, volume contraction and the dealloying of Li x In take place. Induced by the alloying and dealloying of Li x In, the dark and bright strips along the basal plane of InAs NWs appear and disappear alternately during the lithiation–delithiation cycling. Our results provide important insights into the lithiation/delithiation mechanism of III–V group nanomaterials and are envisaged to be helpful for designing lithium ion battery anode materials with fast lithiation speed, small volume expansion and reversible lithiation/delithiation processes.
Nanorods of LiV3O8 are synthesized using citrate assisted sol–gel method followed by room temperate quenching technique. The physical parameters are identified by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), high resolution transmission electron spectroscopy (HR-TEM). The detailed kinetic studies of these electrodes comprising of different weight percentage of conductive carbon and fixed binder concentration are pursued by cyclic voltammetry (CV), in situ electrochemical impedance spectroscopy (EIS) experiments. The in situ EIS results during lithium-ion intercalation and deintercalation processes are discussed on the basis of equivalent electrical circuit model and analyzed by non linear least square fit method. The estimated kinetic parameters are analyzed after obtaining good agreement between fitted EIS spectra and experimental data. The change in the kinetic parameters with varying offset potentials is also discussed within the experimental limit. Due to high apparent lithium-ion diffusion in solid matrix as well as low charge transfer resistance and relatively high exchange current density value, made this nanorod materials attractive for high rate lithium-ion battery applications. Herein, LiV3O8 nanorods exhibit excellent electrochemical properties and demonstrate superior cycling behavior with first discharge capacity of 338mAhg−1, 283mAhg−1, 237mAhg−1 at 101mAg−1 for 30%, 20%, and 10% carbon additive, respectively.
Spontaneous electrical potential is essential and widely exists in living cell membranes of organism, and could provide a novel power-supply system without external stimuli. However, the highly complex and delicate biological structures have restricted the huge electrical energy in practical applications. Herein, we report the spontaneous electric generation of a functional groups-reconfigured graphene oxide membrane in ambient atmosphere, which was prepared by a directionally-induced thermal reduction strategy. The as-prepared asymmetric porous graphene oxide membrane (a-GOM) with a size of only 4 mm2 can proactively generate a sustained electrical voltage of up to 450 mV in air without the need of external stimuli such as mechanical movement, light, heat, and liquid water. Of practical importance, it is easy to reach a high voltage of more than 10 V by simple series stacking of a-GOM units, powering many commercial electronic components such as liquid crystal displays (LCD) and light-emitting diodes (LED). In addition, flexible and foldable power generation devices having soft package technology (being used for the fabrication of commercial lithium-ion batteries) are achievable on the basis of the assembly of a-GOM units.
Cornish et al. (2008, this issue) provide an excellent review of Fragile X a common but very complex cause of intellectual disability. They report on a cohort of such males of normal intelligence quotient (IQ) and socioeconomic status (SES), but who have deficits in selective attention and growing impairment in response inhibition. This paper has theoretical views for our models of the mind and clinical implications for families where Fragile X may never have been considered as a possible cause of some of the problems in male and female family members and possibly as well for other disorders such as attention deficit hyperactivity disorder (ADHD) and autism.
Calcium carbide (CaC2)-derived carbon (CCDC)/polyaniline (PANI) composite materials are prepared by in situ chemical oxidation polymerization of an aniline solution containing well-dispersed CCDC. The structure and morphology of CCDC/PANI composite are characterized by Fourier infrared spectroscopy (FTIR), scanning electron microscope (SEM), transmission electron microscopy (TEM) and N2 sorption isotherms. It has been found that PANI was uniformly deposited on the surface and the inner pores of CCDC. The supercapacitive behaviors of the CCDC/PANI composite materials are investigated with cyclic voltammetry (CV), galvanostatic charge/discharge and cycle life measurements. The results show that the CCDC/PANI composite electrodes have higher specific capacitances than the as grown CCDC electrodes and higher stability than the conducting polymers. The capacitance of CCDC/PANI composite electrode is as high as 713.4Fg−1 measured by cyclic voltammetry at 1mVs−1. Besides, the capacitance retention of coin supercapacitor remained 80.1% after 1000 cycles.
This article develops a linear programming cost minimisation model for the high level system design and corresponding unit commitment of generators and storage within a microgrid; a set of energy resources working co-operatively to create a cost effective, reliable and environmentally friendly energy provision system. Previous work in this area is used as a basis for formulation of a new approach to this problem, with particular emphasis on why a microgrid is different to centralised generation or other grid-connected decentralised energy resources. Specifically, the model explicitly defines the amount of time that the microgrid would be expected to operate autonomously, and restricts flow of heat between microgrid participants to defined cases. The model developed is applied to a set of United Kingdom commercial load profiles, under best current estimates of energy prices and technology capital costs, to determine investment attractiveness of the microgrid. Sensitivity analysis of results to variations in energy prices is performed. The results broadly indicate that a microgrid can offer an economic proposition, although it is necessarily slightly more expensive than regular grid-connected decentralised generation. The analysis results have raised important questions regarding a fair method for settlement between microgrid participants, and game theory has been identified as a suitable tool to analyse aspects of this situation.
Mg2Ni-type alloys, i.e., Mg2Ni, Mg2Ni0.75Cu0.25, Mg2Ni0.6Cu0.4 and Mg2Ni0.75V0.25 were synthesized by mechanical alloying and subsequent thermal treatment starting from a corresponding elemental powder mixture. The kinetics of hydrogen absorption and desorption of annealed materials were measured using a manually controlled Sieverts apparatus. The electrochemical characteristics of Mg2Ni-type alloys were tested for their ability to store hydrogen at room temperature by using constant current to charge and discharge the electrode. The partial substitutions of Cu and V for Ni increased hydrogen absorption and desorption at 200°C and improved the electrochemical storage capacity and cycle life at room temperature.
The emergence of Plug in Battery Electric Vehicles (BEV) is a process which will bring a large aggregate source of distributed energy storage into the electricity industry. The potential exists for this storage to bring benefits from the ability to shift net BEV demand (both charging and vehicle to the grid export) in response to electricity industry needs. The potential for BEV flexibility to act as a Distributed Energy Resource (DER) is however constrained by a range of factors including their mobility, need to serve transport energy requirements, and the locational/temporal availability of physical charging opportunity. This paper addresses the challenge of characterizing the availability of this new storage resource and aims to be of use to policy makers and electricity industry planners in developing strategies for maximizing the value of BEV integration for the electricity industry. In particular it: presents a general discussion of, and framework for understanding the manner in which BEV storage gives rise to charging/discharging flexibility, presents a method for simply characterizing the factors which constrain this flexible resource, introduces a method for empirically establishing a benchmark DER potential which fully accounts for relevant constraints, and applies these methods to a case study of vehicle use in the Sydney Greater Metropolitan area. Results show that, in respect of vehicle transport in Sydney, charging speed and the need to reserve energy in respect of transport needs is a lesser constraint than the impact of charging infrastructure availability. While the DER potential declines during the day in all cases, access to additional charging infrastructure minimizes this decline. Investment in additional non-residential charging infrastructure may therefore be particularly important in maximizing the DER potential arising from BEV storage flexibility, in particular for the opportunity to manage the integration of high future PV generation levels.
The successful electro-synthesis of a composite made of polythiophene nano-wires and platinum nano-particles is reported. The nano-wires were prepared on a Pt electrode previously modified with a mesoporous silica thin film. The silica film modified electrode was also prepared and characterized by electrochemical means. For the electro-polymerization the working solution was 1.0×10−3 molL−1 thiophene and 1.0×10−1 molL−1 tetrabuthylammonium hexafluorophosphate in anhydrous acetonitrile. The nano-structured electrode was characterized and subsequently modified by dispersing platinum nano-particles employing an experimental method based on polymer doping properties. Also, electro-catalytic activity of the composite with respect to formic acid electro-oxidation was verified. The results were outstanding and compare well with those obtained employing a bare polycrystalline platinum electrode. The nano-wire deposit and the composite were analyzed by transmission electron microscopy, confirming the expected morphology and crystalline degree. All these results are of the utmost importance since only simple electrochemical preparative methods were utilized, allowing more control of the process and lowering production cost.
Li4Ti5O12 microspheres composed of nanoflakes wrapped in graphene nanosheets have been synthesized by an advanced microwave-hydrothermal (MW-HT) method for the preparation following by an annealing step. Microwave-assisted synthesis processes are appealing, as they can rapidly synthesize materials with a high degree of control of particle size and morphology at low cost. The resultant composite reveals a unique loose structure which could avoid the restacking of graphene sheets and offer rapid lithium ion diffusion paths. Therefore the Li4Ti5O12/graphene electrode has highly desirable properties: a specific capacity approaching the theoretical value, stable cycling, and exceptional rate capability. The composite also can be a good indicator of the remained charge and discharge capacity since it presents a curved charge and discharge line instead of a stable plateau.
Modern ICT Applications on Tele-health focuses on providing the smart infrastructure that facilitates the delivery of health services. While Internet-of-Things (IoT) and cloud-computing platforms assist the implementation of such architecture, the reliability of service delivery during network disconnection is still an open issue in this domain. This paper proposes a prediction methodology that is able to deliver reliable services with acceptable accuracy by incorporating domain-specific knowledge into exchanged data. The proposed service will be of a great value in a situation where the network availability is not reliable. The contributions of this work are to 1) measure the impact of ontology enrichment on classifying the health data, 2) develop a prediction model that is able to predict patients' readings with an acceptable accuracy, and 3) minimize communicating messages among the network components. Three experiments have been conducted on a real health dataset to measure the performance of the proposed methodology. The results showed that our proposed methodology improved the reliability of the Tele-health services implemented on the top of IoT and cloud-computing platforms.
Ni-rich cathodes have been considered as promising cathodes for Li-ion batteries (LIBs) because their high electrochemical capacities and low costs. However, fast capacity fading caused by interfacial instability and bulk structural degradation of Ni-rich cathodes during charge-discharge processes severely hinders their development and application. To address these challenges, we report a one-step dual-modification strategy to in-situ synthesize complex In2O3&LiInO2 co-coating layer on the surface of LiNi0.8Co0.1Mn0.1O2, which can cooperate collaboratively to stabilize layered structure and deplete lithium impurity. The dual-modified LiNi0.8Co0.1Mn0.1O2 materials not only show distinguished cycling stability at 1 C with a capacity retention of ca. 90%, but also exhibit a discharge capacity of 177.1 mAh g−1 at a high rate of 5 C with a capacity retention of 86.4% after 300 cycles. Further studies confirm structural degradation and intergranular cracks at the particle level can be effectively mitigated by uniformly adherent bi-functional coating layer even after long-term cycling. The results shed light on the feasibility of dual-modified strategy for improving the performance of Ni-rich cathode materials, which can also be applied to other oxide cathode materials.
It has long been known that the performance of the Fe negative electrode in Fe/Ni or Fe/air batteries is improved by the presence of lithium ions in the electrolyte. This work therefore investigated quantitatively the effect of Li+ on the reduction of some FeII and FeIII oxides, as possible intermediates of Fe reduction/oxidation cycles, by comparing the extent of the reduction in pure 6.0M KOH with that in lithiated alkaline media. Fe oxides were studied as pressed powder samples embedded in Ni foam. It was found that, in 6.0M KOH, only FeO is electrolytically reduced at room temperature, whereas Fe2O3 and, to an even greater extent Fe3O4, are very recalcitrant to the reduction process. The situation dramatically changes in, for instance, 4.0M KOH+2.0 LiOH electrolyte, in which the extent of the reduction, even at room temperature, becomes significant for all compounds. This behaviour is very probably due to the reduction of Li+ within the oxide lattice to produce Li x Fe y O z intercalation-compound intermediates, which are then reduced to metallic Fe and Li hydroxide.
The use of fast surface redox storage (pseudocapacitive) mechanisms can enable devices that store much more energy than electrical double-layer capacitors (EDLCs) and, unlike batteries, can do so quite rapidly. Yet, few pseudocapacitive transition metal oxides can provide a high power capability due to their low intrinsic electronic and ionic conductivity. Here we demonstrate that two-dimensional transition metal carbides (MXenes) can operate at rates exceeding those of conventional EDLCs, but still provide higher volumetric and areal capacitance than carbon, electrically conducting polymers or transition metal oxides. We applied two distinct designs for MXene electrode architectures with improved ion accessibility to redox-active sites. A macroporous Ti3C2Tx MXene film delivered up to 210 F g−1 at scan rates of 10 V s−1, surpassing the best carbon supercapacitors known. In contrast, we show that MXene hydrogels are able to deliver volumetric capacitance of ∼1,500 F cm−3 reaching the previously unmatched volumetric performance of RuO2.
A series of novel Co–S–B systems were prepared by simple chemical reduction method as the anode material for secondary alkaline batteries. The prepared samples were investigated by inductivity coupled plasma optical emission spectrum (ICP), Brunauer–Emmetr–Teller (BET) method, scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray energy dispersive spectroscopy (EDS) and charge–discharge method. It was found that the BET surface area of Co–S–B system increases and its particle size decreases with increasing the sulfur content. Sulfur incorporation suppresses initial capacity fading of Co–B compound due to irreversible dissolution of boron, and Co–S–B electrodes show enhanced electrochemical capacity and excellent cycle performance. The discharge capacity of Co75.4B17S7.6 reaches 513.6mAh/g at a moderate current density of 100mA/g and 470mAh/g after 60 cycles, which is about 1.5 times that of conventional AB5-type alloy. A proper mechanism was proposed to explain the electrochemical reaction process of Co–S–B electrode.
The accelerated degradation of carbon based supercapacitors utilizing 1M Et4NBF4 in acetonitrile and in propylene carbonate as electrolyte is investigated for a constant cell voltage of 3.5V as a function of the positive over total electrode mass ratio. The degradation rate of the supercapacitor using acetonitrile as a solvent can be decreased by increasing the mass of the positive electrode. With a mass ratio (positive electrode mass/total electrode mass) of 0.65 the degradation rate is minimum. For the capacitor utilizing propylene carbonate as a solvent a similar effect was observed. The degradation rate was smallest for a mass ratio above 0.5.
The aim of this study was to evaluate the influence of different bleaching gels on the masking and caries-arresting effects of infiltrated and non-infiltrated stained artificial enamel caries lesions.
Nowadays, lead-acid battery grids are manufactured mostly from low-antimony and lead–calcium alloys. A variable corrosion resistance of battery grids is caused by either battery operation conditions, purity of used alloy components, an alloy makeup, and the castings quality. Such compositions as usual lead–antimony alloy, low-antimony lead–arsenious alloy and lead–calcium alloy with moderate content of tin today may be regarded as the most studied ones. A significant share of published works has been devoted to low-antimony lead–tin alloys. In the present article, results of corrosion tests of the samples made with application of cadmium as the second component of low-antimony alloy, has been represented. Several samples were extra-alloyed by selenium and silver. Samples of lead–calcium and usual antimony alloys as well as pure lead samples were being tested simultaneously. Upon termination of polarization, weight of anodic films referred to a unit of the sample surface has been determined. Thus, the film covering lead–antimony alloy sample has the maximal weight, whereas the oxidation products on the pure lead surface have the lowest one. Among low-antimony alloys, the highest corrosion resistance has been found out with the samples alloyed by a low amount of silver. The microstructure of the castings surface has been analysed. Process of corrosion has been considered in connection with size of grains.
Research progress of high-energy performance and interfacial phenomena of Li1.13Mn0.463Ni0.203Co0.203O2 cathode and graphite anode in a 55 °C full-cell under an aggressive charge cut-off voltage to 4.7 V (4.75 V vs. Li/Li+) is reported. Although anodic instability of conventional electrolyte is the critical issue on high-voltage and high-temperature cell operation, interfacial phenomena and the solution to performance improvement have not been reported. Surface spectroscopic evidence revealed that structural degradation of both cathode and anode materials, instability of surface film at cathode, and metal-dissolution from cathode and -deposition at anode, and a rise of interfacial resistance with high-voltage cycling in 55 °C conventional electrolyte are resolved by the formation of a stable surface film with organic/inorganic mixtures at cathode and solid electrolyte interphase (SEI) at anode using blended additives of fluorinated linear carbonate and vinylene carbonate. As a result, significantly improved cycling stability of 77% capacity retention delivering 227−174 mAhg−1 after 50 cycles is obtained, corresponding to 819−609 Wh per kg of cathode active material. Interfacial stabilization approach would pave the way of controlling the performance and safety, and widening the practical application of Li-rich layered oxide cathode materials and high-voltage electrolyte materials in various high-energy density Li-ion batteries.