batterydata/paper-abstracts huggingface dataset:
Mate-Kole CC, Conway J, Catayong K, Bieu R, Sackey NA, Wood R, Fellows R. Validation of the revised Quick Cognitive Screening Test. Objective To validate the revised version of the Quick Cognitive Screening Test (QCST). Design Cross-sectional. Setting Senior homes; hospital; college campus. Participants Participants (N=377; 114 men, 263 women) were recruited comprising healthy controls (n=201; 40 men, 161 women), subjects with dementia (n=93; 34 men, 59 women) including Alzheimer disease (n=73) and vascular dementia (n=20); subjects with psychiatric illness (n=35, 15 men, 20 women), specifically schizophrenia or bipolar disorder; and subjects with other neurologic conditions (n=48, 25 men, 23 women) such as traumatic brain injury (n=12) and cerebrovascular disease (n=31). Diagnoses were confirmed by physicians using appropriate criteria. Recruitment was done in the northeastern region. Interventions Not applicable. Main Outcome Measures In an effort to examine the reliability and validity of the revised QCST, participants were administered the revised QCST with a number of standardized measures (ie, Alzheimer's Disease Assessment Scale-Cognitive, Mini-Mental State Examination, Tests of Oral Fluency, Trail-Making Test, and Functional Activities Questionnaire). Results The results revealed that the revised QCST discriminated between healthy controls and the neuropsychiatric participants. Additionally, the revised QCST significantly correlated with other standardized measures, confirming the revised QCST's reliability and validity as a screening instrument for subjects with cognitive deficits. Conclusions The revised QCST provides the clinician with a short yet reliable screening instrument in detecting cognitive deficits in subjects with dementia and other neurologic conditions.
Globally, buildings are responsible for approximately 40% of the total world annual energy consumption. Most of this energy is for the provision of lighting, heating, cooling, and air conditioning. Increasing awareness of the environmental impact of CO2 and NO x emissions and CFCs triggered a renewed interest in environmentally friendly cooling, and heating technologies. Under the 1997 Montreal Protocol, governments agreed to phase out chemicals used as refrigerants that have the potential to destroy stratospheric ozone. It was therefore considered desirable to reduce energy consumption and decrease the rate of depletion of world energy reserves and pollution of the environment. This article discusses a comprehensive review of energy sources, environment and sustainable development. This includes all the renewable energy technologies, energy efficiency systems, energy conservation scenarios, energy savings and other mitigation measures necessary to reduce climate change.
An investigation into the characterization of the thermodynamic equilibrium between the α-Al2O3 and Na-β-alumina phases as a function of sodium activity is reported here for the first time using a novel approach. A sodium reference electrode comprising vitreous NaAlSi3O8 along with Al2O3 and SiO2 in conjunction with an yttria stabilized zirconia (YSZ) disk was used to vary the oxygen potential and in turn, the sodium potential, by application of a potential difference across YSZ. This system was found to be promising for use as a potential sodium reference electrode. The results from the present investigation showed there exists a very narrow or no window of sodium activity over which the sodium oxide activity in a α-Al2O3/β-Al2O3 system remains invariant unlike a wide range found for the β/β″-alumina system.
Rationally designed graphene nanomesh assembled foam (GMF) with hierarchical pore arrangement has been successfully fabricated for the first time by a site-localized nanoparticle-induced etching strategy on the basis of hydrothermally self-assembled graphene architecture. The newly developed GMF provides a new material platform for developing high-performance functional devices. Specially, the N- and S-codoped GMF electrode exhibits excellent electrocatalytic activities for oxygen reduction reaction (ORR), better than most of the graphene-based ORR catalysts reported previously.
Grapheme-colour synaesthesia is an atypical condition characterized by the perception of colours when reading achromatic text. We investigated the level of colour processing responsible for these experiences. To do so, we tapped a central characteristic of colour perception. In different lighting conditions the same wavelength of light can prompt the perception of different colours. This helps humans recognize distinctive coloured objects despite changes in illumination. We wanted to see if synaesthetic colours were generated at a neural locus that was susceptible to colour constancy analyses. We used colour matching and naming tasks to examine interactions between simulated coloured illuminants and synaesthetic colours. Neither synaesthetic colour matching or naming was impacted. This contrasted with non-synaesthetic control participants, who performed the colour-matching task with graphemes physically coloured to mimic synaesthesia. Our data suggest that synaesthetic colour signals are not generated at lower-levels of colour processing, but are introduced at higher levels of analysis and are therefore not impacted by the processes responsible for perceptual constancy.
In this paper, we report a technique that uses piezoelectric polyvinylidene fluoride (PVDF) microbelts to convert the energy from low-speed air flow to electricity via their resonant oscillation. The micrometre thick PVDF thin films were fabricated by a top-down reactive ion etching process, where the thickness was controlled by etching time and the piezoelectric phase was well preserved. The thickness, air flow speed and electrical output relationship was predicted theoretically and characterized experimentally. The PVDF microbelts were able to generate sufficient electrical energy from low speed air flow for the sustained operation of small electronic devices. Their capability for harvesting energy from simulated respiration was also demonstrated.
This paper describes an investigation with an objective to screen and select high performance membrane materials for a working, rechargeable lithium–air battery. Membrane laminates comprising glass–ceramic (GC) and polymer–ceramic (PC) membranes were assembled, evaluated and analyzed. A superionic conducting GC membrane with a chemical composition of Li1+x Al x Ge2−x (PO4)3 (x =0.5) was used. Polymer membranes comprising of PC(BN), PC(AlN), PC(Si3N4) and PC(Li2O) electrochemically coupled the GC membrane with the lithium anode. The cell and membrane laminates were characterized by determining cell conductivity, open circuit voltage and carrier concentration and its mobility. The measurements identified Li2O and BN as suitable dopants in polymer matrix which catalyzed anodic charge transfer reaction, formed stable SEI layer and provided high lithium ion conductivity.
SnSb–TiC–C nanocomposite alloy anodes for lithium-ion batteries have been synthesized by a mechanochemical process involving high-energy mechanical milling of Ti–Sn and Ti–Sb precursors with carbon black. Characterization of the formed nanocomposites using x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) reveals that these alloys are composed of crystalline nanoparticles of SnSb dispersed in a matrix of crystalline TiC and amorphous carbon. The SnSb–TiC–C alloy shows an initial gravimetric capacity of 769 mAh g−1 (1385 mAh cm−3), an initial coulombic efficiency of 84.9%, and a tap density of 1.8 g cm−3. The buffer matrix of TiC and carbon in the nanocomposite alloy anodes accommodates the large volume change occurring during the charge–discharge process and leads to enhanced cyclability compared to pure SnSb anodes as well as previously published SnSb composites.
Biochar prepared from the pyrolysis of maple wood was studied as supercapacitor electrode materials. Three kinds of electrodes were fabricated: mini-chunk electrodes, thin-film electrodes, and large-disk-chunk electrodes. Their capacitive behaviors were studied using cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The mini-chunk supercapacitor shows an electrochemical behavior similar to the supercapacitor using the thin-film electrodes. It exhibits outstanding performance characteristic of a high specific capacitance of approximately 32 F g−1 and a high stability without obvious capacitance decays upon 2,600 potential cycles. This indicates that the mini-chunk supercapacitor can be used as an mF-scale power source for electronic device applications. Moreover, the mini-chunk electrode provides a simple and fast technique to evaluate biochar materials used as potentially high-performance, low-cost, and environmental friendly supercapacitor electrodes without the need of binder and complicated fabrication procedures. However, the supercapacitor using large-disk-chunk biochar electrodes shows lower specific capacitive performance due to the high ohmic resistance stemming from long tubular structures within biochar.
Several studies have conducted empirical research on different aspects of total factor productivity. However, the estimation of its degree of integration, which has important usefulness for policy formulation, forecasting purposes and econometric modeling, has been greatly overlooked in the literature. The purpose of this paper is to examine the stationarity properties of total factor productivity in 79 economies for the period 1970–2011. Using a newly constructed dataset and a new nonstationarity test that provide for nonlinearity in the estimations, the empirical results show that the series in 67 countries (or 85 % of the total sample) follow the unit root process. In other words, the total factor productivity in these countries are integrated of order one. For the remaining 12 countries (or 15 % of the total sample), we observe that the series exhibit stationary process. We discuss the policy implications of these findings and offer suggestions for further research.
Mobile device capabilities have increased tremendously in recent years, and the complexity of the applications executed in these devices has evolved accordingly. However, despite the efforts made by mobile manufactures, resource consumption, particularly battery and data traffic, are still limiting factors for mobile applications. The most important aspects determining the consumption of a mobile application is its software architecture and its behaviour. Hence, by comparing the resource consumption of different software architectures before an application is built, mobile developers can make decisions that are better informed. This work presents the consumption analysis of two applications, each of them built with two different architectures in order to identify under which situation each architecture is more efficient. In addition, by generalizing the analysis of the two applications, a conceptual framework is created with which to analyse the consumption pattern of applications in their early development phases. This conceptual framework will allow mobile developers to estimate the resource consumption of their applications under different conditions of software architecture and usage scenarios, providing them with information relevant for decision making.
The present study examined the relative magnitudes of local-scale versus large-scale latitudinal patterns of intertidal body temperatures, using data loggers mimicking limpets from the genus Patella. Over approximately 18months, loggers collected continuous 30-minute resolution data on body temperatures at a variety of microhabitats on 13 rocky shores along the Atlantic coast of the Iberian Peninsula. Data showed that during low tide, body temperatures of sun-exposed animals routinely reached much higher temperatures than their counterparts attached to north-facing, shaded surfaces. Sunny versus shaded differences were consistently larger than the variability associated with the seasons and with shore level. Moreover, daily variation far exceeded that observed when considering only averaged sea surface temperature. Therefore, analysing temperature at the scales of the organisms may provide a wealth of information more suited to understand and model the distribution of intertidal species under present and future climatic scenarios.
The annealing treatment was found to result in the improvement in the cyclic stability but the degradation of discharge capacity, activation and high-rate dischargeability for Zr0.5Ti0.5Mn0.5V0.3Co0.2Ni1.1 alloy electrode. A lower discharge potential in the annealed alloy electrode was found owing to a more homogeneous alloy, which is consistent with the pressure–composition isotherms (P–C–T) measurement. We found that the annealed alloy also had lower and flatter pressure plateaus, and larger pressure hysteresis. At high discharge rates, the hydrogen diffusion in the bulk of the alloy was the rate-determining step. The diffusion coefficients for hydrogen in the annealed and as-cast alloys were calculated to be 1.4×10−12 cm2 s−1 and 4.3×10−12 cm2 s−1, respectively. The lowering of high-rate discharge capacity can be ascribed to the reason that the hydrogen diffusion coefficient is lower due to homogeneous microstructure in the annealed alloy.
Amorphous red phosphorus/carbon nanotubes (ARPC) composites are prepared by planetary ball-milling technique with the pre-milling red phosphorus processes, consisting of uniformly distributing amorphous red phosphorus embedding in a three-dimensional conductive scaffold of interconnected carbon nanotubes (CNTs). Combining the three-dimensional conductive network with the amorphous red phosphorus can not only alleviate the volumetric change in the charging/discharging processes, but also provide conductive network for electron transport and dramatically improve the specific capacity, cycling stability and rate capability of the composite electrode. The ARPC composites deliver a high initial charge capacity of 2133.4 mAh g−1 at a current density of 0.05 C and maintain a reversible capacity of 998.5 mAh g−1 with a high Coulombic efficiency of approximately 99% after 50 cycles. Meanwhile, the composite can maintain high specific capacities of 1993.8 mAh g−1, 1896.9 mAh g−1, 1546.8 mAh g−1 and 816.6 mAh g−1 at 0.01 C, 0.05 C, 0.1 C and 0.5 C, respectively. Compared with that of the ball-milled amorphous red phosphorus with or without CNTs, the pre-milled ARPC composites show much better electrochemical performances.
Global environmental concerns and the escalating demand for energy, coupled with steady progress in renewable energy technologies, are opening up new opportunities for utilization of renewable energy resources. Solar energy is the most abundant, inexhaustible and clean of all the renewable energy resources till date. The power from sun intercepted by the earth is about 1.8×1011 MW, which is many times larger than the present rate of all the energy consumption. Photovoltaic technology is one of the finest ways to harness the solar power. This paper reviews the photovoltaic technology, its power generating capability, the different existing light absorbing materials used, its environmental aspect coupled with a variety of its applications. The different existing performance and reliability evaluation models, sizing and control, grid connection and distribution have also been discussed.
There is need for a battery model that can accurately describe the battery performance for an electrical system, such as the electric drive train of electric vehicles. In this paper, both linear and non-linear equivalent circuit models (ECM) are employed as a means of extracting the battery parameters that can be used to model the performance of a battery. The linear and non-linear equivalent circuit models differ in the numbers of capacitance and resistance; the non-linear model has an added circuit; however their numerical characteristics are equivalent. A multi-objective genetic algorithm is employed to accurately extract the values of the battery model parameters. The battery model parameters are obtained for several existing industrial batteries as well as for two recently proposed high performance batteries. Once the model parameters are optimally determined, the results demonstrate that both linear and non-linear equivalent circuit models can predict with acceptable accuracy the performance of various batteries of different sizes, characteristics, capacities, and materials. However, the comparisons of results with catalog and experimental data shows that the predictions of results using the non-linear equivalent circuit model are slightly better than those predicted by the linear model, calculating voltages that are closer to the manufacturers’ values.
A composite consisting of sulfur/dehydrogenated polyacrylonitrile is one of the most promising cathode materials for use in rechargeable lithium–sulfur batteries. However, the reported sulfur contents have been low, less than 50 wt%, which compromise the intrinsic high specific capacity and energy of elemental sulfur and hence decrease significantly the specific energy of the composite. To identify the potential to further increase the sulfur content, we elucidate the binding mechanism of sulfur and polyacrylonitrile in their composite. The heat treatment experiments at varying timespans with excess sulfur showed a constancy of sulfur content after a critical length of timespan, indicating the saturation of sulfur in the structure of dehydrogenated polyacrylonitrile. Based on molecular structure and size consideration, it is proposed that the binding involves the formation of an 8 membered ring of sulfur embedded between 4 heterocyclic rings of dehydrogenated polyacrylonitrile. From this model and experimental results, we show that there exists an upper limit of sulfur content in the sulfur/dehydrogenated polyacrylonitrile composite at 56 wt%.
In this study, functionalized carbon nanotubes (CNTs) with good conductivity and high surface area are anchored with mesoporous Co3O4 nanoparticles by a facile chemical co-precipitation method. Electrochemical characterizations show that Co3O4/CNT nanocomposite delivers a capacity of 873mAhg−1 after 50 cycles at a current density of 100mAg−1. When the current density is increased to 250, 350 and 500mAg−1, it still maintains a capacity of 895, 834 and 757mAhg−1, respectively. The high capacity, rate capability and good cycling ability of Co3O4/CNT nanocomposite are attributed to the intimate interaction between the CNTs and Co3O4 nanoparticles. The CNTs not only enhance the conductivity of Co3O4 nanoparticles but also improve the structure stability of Co3O4 nanoparticles. Furthermore, the mesoporous structure of Co3O4 nanoparticles is available to the transfer of electrolyte. Our results demonstrate that CNTs reinforced Co3O4 nanocomposite could be a promising anode material for high capacity lithium-ion batteries.
Carbon coated Li3V2(PO4)3 cathode material was prepared by a poly(vinyl alcohol) (PVA) assisted sol–gel method. PVA was used both as the gelating agent and the carbon source. XRD analysis showed that the material was well crystallized. The particle size of the material was ranged between 200 and 500nm. HRTEM revealed that the material was covered by a uniform surface carbon layer with a thickness of 80Å. The existence of surface carbon layer was further confirmed by Raman scattering. The electrochemical properties of the material were investigated by charge–discharge cycling, CV and EIS techniques. The material showed good cycling performance, which had a reversible discharge capacity of 100mAhg−1 when cycled at 1C rate. The apparent Li+ diffusion coefficients of the material ranged between 9.5×10−10 and 0.9×10−10 cm2 s−1, which were larger than those of olivine LiFePO4. The large lithium diffusion coefficient of Li3V2(PO4)3 has been attributed to its special NASICON-type structure.
A three-dimensional (3D), two-phase, isothermal model of direct methanol fuel cells (DMFCs) was employed to investigate effects of electron transport through the backing layer and the land in bipolar plates. It was found that the electronic resistance of the backing layer, affected by backing layer electronic conductivity, backing layer thickness and flow channel width, played a relatively important role in determining the current density distribution and cell performance. In order to ignore the electron transport effect on the average current density, the minimum electronic conductivity of the backing layer has to be 1000Sm−1, with the relative error in the average current density less than 5%, under the given conditions.
The porous ZnO/C composites derived from metal organic framework-5 (MOF-5) is obtained via a calcination method subsequent to hydrothermal process. The results of materials characterization analysis show that the porous ZnO/C composites is well-crystallized with cube morphology and possesses a large specific surface area. According to the electrochemical measurements, the porous ZnO/C composites as anodic materials for Nickel–Zinc rechargeable battery exhibits excellent electrochemical performance compared with that of the commercial ZnO, keeping the discharge specific capacity at 587 mAh g−1 with the capacity retention ratio of about 89.1% after 800 cycles. The outstanding electrochemical property of porous ZnO/C composites can be ascribed to the interconnected conductive network generated by the carbon layer and stable cube architectures derived from metal organic framework-5 precursor, which can facilitate the transportation of electrons and restrain the formation of zinc dendrites during repeated charge-discharge cycling. Furthermore, a novel sphere structure consisting of numerous intersecting disk-like sheets is transformed from the cubic porous ZnO/C composites after 600 cycles, which can contribute to the uniform current distribution and improve the performance of energy storage, revealing the truth for the long cycle life of porous ZnO/C composites.
Lithium-sulfur (Li-S) battery could bring a step-change in battery technology with a potential specific energy density of 500 - 600 Wh/kg. A key challenge for further improving the specific energy-density of Li-S cells is to understand the mechanisms behind reduced sulfur utilisation at low electrolyte loadings and high discharge currents. While several Li-S models have been developed to explore the discharge mechanisms of Li-S cells, they so far fail to capture the discharge profiles at high currents. In this study, we propose that the slow ionic transport in concentrated electrolyte is limiting the rate capability of Li-S cells. This transport-limitation mechanism is demonstrated through a one-dimensional Li-S model which qualitatively captures the discharge capacities of a sulfolane-based Li-S cell at different currents. Furthermore, our model predicts that a discharged Li-S cell is able regain some capacity with a short period of relaxation. This capacity recovery phenomenon is validated experimentally for different discharge currents and relaxation durations. The transport-limited discharge behavior of Li-S cells highlights the importance of optimizing the electrolyte loading and electrolyte transport property in Li-S cells.