batterydata/paper-abstracts huggingface dataset:
Brauer SG, Bew PG, Kuys SS, Lynch MR, Morrison G. Prediction of discharge destination after stroke using the Motor Assessment Scale on admission: a prospective, multisite study. Objective To determine if admission functional status, measured with the Motor Assessment Scale (MAS), was predictive of discharge destination to home or residential aged care in patients with stroke undergoing rehabilitation. Design Cohort study. Setting Inpatient rehabilitation units. Participants Adults (N=566) diagnosed with stroke undergoing inpatient physiotherapy at one of 15 units in Australia. Intervention Multidisciplinary rehabilitation. Main Outcome Measure Discharge home versus residential aged care. Results Prestroke residential status, gait ability measured with the MAS (MAS-5), rolling ability (MAS-1), and age were able to correctly predict 99% of patients with stroke discharged home and 33.3% discharged to residential aged care facilities, producing an accuracy of 87.3%. Odds ratios indicate that for every 1-point increase in MAS-5 (gait), subjects were 1.66 times more likely to go home (95% confidence interval [CI], 1.28–2.27; P<.001). Similarly, for every 1-point increase in MAS-1 (rolling), subjects were 1.28 times more likely to go home (95% CI, 1.11–1.49; P<.01). Conclusions Two items of the MAS assessed on admission to rehabilitation—gait and rolling—in conjunction with basic demographic information of age and prestroke residential status, were highly predictive of discharge from rehabilitation to home.
Empirical models for particulate matter emissions from paved road surfaces have been criticised for their lack of realism and accuracy. To support the development of a less empirical model, a study was conducted in a busy street at the DAPPLE site in Central London to understand the processes and to identify important parameters that influence emission from paved roads. Ordinary road gritting salt was applied to the road and the particulate matter entering the air at near-road surface level was monitored using optical particle counters. The grit acted as a tracer. The grit moved rapidly along the road in the direction of traffic flow. Build-up of material at the kerb indicated material being thrown across the road by the traffic. Coarser particles were resuspended faster than the finer ones. A clear decay profile was seen in the case of particles larger than 2 μ m ; particles smaller than 2 μ m did not show any decay pattern during the experiment duration. Grinding of material appears to control the reservoir of fine particles on the road surface. The amount of material resuspended by traffic is about 30% less than those removed along the road and a factor of 6 higher than the amount removed across the road. Resuspension accounts for 40% of the total material removed from a road segment and 70% of the material removed together along and across the road. On average a single vehicle pass removes 0.08% of material present on a road segment at that instant. The calculation scheme is obtained from a short-duration study and therefore further studies of long duration involving varying road geometry and different traffic and meteorological condition need to be carried out before applying parameter estimates presented in this paper.
Silicene, germanene and stanene likely to graphene are atomic thick material with interesting properties. We employed first-principles density functional theory (DFT) calculations to investigate and compare the interaction of Na or Li ions on these films. We first identified the most stable binding sites and their corresponding binding energies for a single Na or Li adatom on the considered membranes. Then we gradually increased the ions concentration until the full saturation of the surfaces is achieved. Our Bader charge analysis confirmed complete charge transfer between Li or Na ions with the studied 2D sheets. We then utilized nudged elastic band method to analyze and compare the energy barriers for Li or Na ions diffusions along the surface and through the films thicknesses. Our investigation findings can be useful for the potential application of silicene, germanene and stanene for Na or Li ion batteries.
The porous structure of pitch-based carbon aerogels (P-CAs) can be modified by KOH activation. It is found that decreasing the carbonization temperature of precursor CAs and increasing the mass ratio of KOH to CAs help to the formation of 0.7nm-sized micropores and 2.7nm-sized mesopores, respectively. The origin and the pore size of micropores play an important role in controlling electrochemical properties. The carbonization-forming micropores have stronger energy storage efficiency than activation-forming micropores, and only those with diameter below 1nm (Microp<1nm) are the crucial place to storage energy. Due to the substantive increase of the number of the Microp<1nm, the highest specific capacitance of the as-prepared activated samples can reach 187.2Fg−1 at 5mAcm−2, 1.8 times as large as that of their precursor CAs. Furthermore, this capacitance is still up to 173.3Fg−1 when increasing the current density to 50mAcm−2, indicating that the activated samples have a high-rate charge–discharge performance.
Three lead-based materials formed by PbO2, PbO and Pb as main phases were prepared by following different synthetic procedures and tested as anodic materials in Li-ion batteries by using potentiostatic and galvanostatic methods. While the reduction of Pb(IV) to Pb(II) takes place in a single step, that of Pb(II) to Pb is a complex process involving several steps. Both reduction reactions are irreversible. Lead, whether electrochemically or chemically formed, undergoes an electrochemical reaction with lithium that over the 1.0–0.0 V potential range yields Li x Pb alloys (0≤x≤4.4). The anodic and cathodic potentiostatic curves exhibit various signals that account for: (i) the formation of different intermediates with variable lithium contents; (ii) the reversibility of the alloying/de-alloying processes; (iii) the increase in complexity of such processes as the oxidation state of lead in them decreases. This results in capacity fading with cycling, particularly in the samples having Pb as the main component. One way of avoiding the capacity loss on cycling involves depositing the active material on lead sheets from spraying suspensions. These coatings exhibit a good capacity retention, which can be ascribed to the formation of a Li x Pb layer at the active material/substrate interface that facilitates electron and ion transfer across the electrode.
Sleep-disordered breathing (SDB) prevalence peaks in preschool children and is associated with deficits in cardiovascular functioning during sleep. No long-term studies have investigated the effects of SDB resolution in mitigating these outcomes. We hypothesized that following 3 years, normalization of alterations to heart rate (HR), pulse transit time (PTT), heart rate variability (HRV), and urinary catecholamines identified at the initial diagnosis would be associated with resolution of SDB.
Spherical hierarchical LiFePO4/C cathode material was fabricated by a facile sol spray drying method using FePO4•2H2O, LiOH, oxalate acid (H2C2O4•2H2O) and sucrose as raw materials. A relatively low drying temperature 180°C was adopted in order to form a uniform and thin carbon layer on the surface. The LiFePO4/C sample was characterized by physical and electrochemical measurements and the influence of the specific morphology on the electrochemical property was investigated. This cathode material had a reversible capacity of 160.9mAhg−1 at 0.1C and maintained 105.8mAhg−1 at as high as 20C with superior cycling performance. The excellent electrochemical property should be attributed to the carbon coated nanoparticles and a large specific surface area (36.5m2 g−1) provived by the spherical hierarchical structure.
Electrochemical gas–solid reactions are important for many energy technologies, involving partial pressure dependent surface catalysis and bulk conduction phenomenon unresolvable using conventional techniques. We report for the first time water and CO2 reactivity on perovskites, fluorites, and their composites across a wide temperature- oxygen partial pressure (pO2) range by in situ gas phase isotopic oxygen exchange, demonstrating that multivalent metal oxides actively “breathe” oxygen from these gasses. We reveal the importance of cation oxidation state and the roles of electronic, ionic, and mixed conductor phases, as well as their composites. Moreover, we show that an ionic and electronic conducting oxide composite dramatically modifies the kinetics of oxygen exchange as compared to these materials individually or as compared to the effect of creating a composite from two mixed conducting oxides.
We report a simple synthesis route towards a new type of comb polymer material based on polyether amines oligomer side chains (i.e., Jeffamine® compounds) and a poly(ethylene-alt-maleic anhydride) backbone. Reaction proceeds by imide ring formation through the NH2 group allowing for attachment of side chains. By taking advantage of the high configurational freedoms and flexibility of propylene oxide/ethylene oxide units (PO/EO) in Jeffamine® compounds, novel polymer matrices were obtained with good elastomeric properties. Fully amorphous solid polymer electrolytes (SPEs) based on lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and Jeffamine®-based polymer matrices show low glass transition temperatures around −40 °C, high ionic conductivities and good electrochemical stabilities. The ionic conductivities of Jeffamine-based SPEs (5.3 × 10−4 S cm−1 at 70 °C and 4.5 × 10−5 S cm−1 at room temperature) are higher than those of the conventional SPEs comprising of LiTFSI and linear poly(ethylene oxide) (PEO), due to the amorphous nature and the high concentration of mobile end-groups of the Jeffamine-based polymer matrices rather than the semi-crystalline PEO The feasibility of Jeffamine-based compounds in lithium metal batteries is further demonstrated by the implementation of Jeffamine®-based polymer as a binder for cathode materials, and the stable cycling of Li|SPE|LiFePO4 and Li|SPE|S cells using Jeffamine-based SPEs.
To develop next-generation lithium-ion batteries (LIBs) with novel designs, reconsidering traditional materials with enhanced cycle stability and excellent rate performance is crucial. We herein report the successful preparation of three-dimensional (3D) composites in which spilt Sn–Cu alloys are uniformly dispersed in an amorphous carbon nanofiber matrix (Sn–Cu–CNFs) via one-step carbonization-alloying reactions. The spilt Sn–Cu alloys consist of active Cu6Sn5 and inactive Cu3Sn, and are controllable by optimization of the carbonization-alloying reaction temperature. The 3D carbon nanofiber framework allowed the Sn–Cu–CNFs to be used directly as anodes in lithium-ion batteries without the requirement for polymer binders or electrical conductors. These composite electrodes exhibited a stable cyclability with a discharge capacity of 400mA h g−1 at a high current density of 1.0Ag−1 after 1200 cycles, as well as an excellent rate capability, which could be attributed to the improved electrochemical properties of the Sn–Cu–CNFs provided by the buffering effect of Cu3Sn and the 3D carbon nanofiber framework. This one-step synthesis is expected to be widely applicable in the targeted structural design of traditional tin-based anode materials.
A growing number of prognostic indices for chronic obstructive pulmonary disease (COPD) is developed for clinical use. Our aim is to identify, summarize and compare all published prognostic COPD indices, and to discuss their performance, usefulness and implementation in daily practice.
Acquisition of time knowledge (TK; the correct representation and use of time units) is linked to the development of numerical abilities, but this relationship has not been investigated in children. The current study examined the acquisition of TK and its association with numerical skills. A total of 105 children aged 6 to 11 years were interviewed with our Time Knowledge Questionnaire (TKQ), developed for purposes of this study, and the Zareki-R, a battery for the evaluation of number processing and mental calculation. The TKQ assessed conventional time knowledge (temporal orientation, temporal sequences, relationships between time units, and telling the time on a clock), estimation of longer durations related to birthday and life span, and estimation of the duration of the interview. Time knowledge increased with age, especially from 6 to 8 years, and was strongly linked to numerical skills. Regression analyses showed that four numerical components were implicated in TK: academic knowledge of numbers and number facts (e.g., reading Arabic numerals, mental calculation), number line estimation (e.g., correspondence between a number and a distance), contextual estimation (e.g., many/few leaves on a tree, children in a family), and numerical tasks involving verbal working memory (e.g., comparison of numbers presented orally). Numerical correlations with TK varied according to children’s age; subtests based on academic knowledge of numbers, working memory, and number line estimation were linked with TK in the younger children, but only contextual estimation was associated with TK in the older children.
Nail penetration into a battery pack, resulting in a state of short-circuit and thus burning, is likely to occur in electric car collisions. To demonstrate the behavior of a specific battery when subject to such incidents, a standard nail penetration test is usually performed; however, conducting such an experiment is money consuming. The purpose of this study is to propose a numerical electrochemical model that can simulate the test accurately. This simulation makes two accurate predictions. First, we are able to model short-circuited lithium-ion batteries (LIBs) via electrochemical governing equations so that the mass and charge transfer effect could be considered. Second, the temperature variation of the cell during and after nail penetration is accurately predicted with the help of simulating the temperature distribution of thermal runaway cells by thermal abuse equations. According to this nail penetration model, both the onset of battery thermal runaway and the cell temperature profile of the test are obtained, both of which are well fitted with our experimental results.
Currently commercialised stand-alone street lighting systems based on the classical configuration coupling photovoltaic cells (PV) and battery cannot work all the year round in regions that are far from the equator. To improve the classical system, a hybrid system coupling a PV, a battery and a fuel cell is proposed. However, the sizing method of hybrid systems is a key issue in obtaining the cheapest system. To optimise the system, an original time-saving method is applied. Two optimization methods are used: first the genetic algorithms, then the simplex algorithms. A simulation model is used to evaluate the validity of the different hybrid configurations. After presenting the problem of stand-alone street lighting, the optimization methodology and the simulation model are detailed. Finally, an optimal configuration is obtained and shows that a 60W street light would cost 7150€ with a lifetime of 25 years. The optimised parameters are also given and analysed.
The objective of this work is to study the recycling of sealed nickel–cadmium batteries through cadmium distillation using a carbonaceous material as reducing agent. In spite of the existence of some industrial processes for nickel–cadmium batteries recycling, there are few fundamental studies about this subject. For the study of the reducing process, coal was added to the material of electrodes. Reduction process was performed from 700 to 1000°C with different quantities of reducing added to the load. Results showed that cadmium purity is of approximately 99.92% and the main impurity found was zinc at around 200ppm. A Ni–Co alloy containing 100ppm cadmium was also obtained.
The low ionic conductivity is a bottleneck of the inorganic solid state electrolyte used for lithium ion battery. In ceramic electrolytes, grain boundary usually dominates the total conductivity. In order to improve the grain boundary effect, an amorphous silica layer is introduced into grain boundary of ceramic electrolytes based on lithium–lanthanum–titanate, as evidenced by electron microscopy. The results showed that the total ionic conductivity could be to be enhanced over 1×10−4 S/cm at room temperature. The reasons can be attributed to removing the anisotropy of outer-shell of grains, supplement of lithium ions in various sites in grain boundary and close bindings among grains by the amorphous boundary layer among grains.
Many studies have found that patients with Alzheimer’s disease (AD) perform significantly worse than normal controls on verbal fluency tasks. Moreover, some studies have found that AD patients’ deficits compared to controls are more severe for semantic fluency (e.g., vegetables) than for letter fluency (e.g. words that begin with F). These studies, however, have not taken category size into account. A comparison of AD patients and age-matched controls on three semantic and three letter categories revealed that both the size and type of a category significantly predicted AD patients’ deficits on verbal fluency tasks. These results suggest that the verbal fluency of AD patients will be most attenuated on large semantic categories.
Co3O4 and Co3O4/CoO nanoparticles have been synthesized by a one-step solution combustion process by adjusting the molar ratio of citric acid (fuel) and Co(NO3)2·6H2O (oxidizer). The effects of citric acid/Co(NO3)2·6H2O molar ratios on phase composition and morphology of products were investigated by XRD and SEM. With the increase of the fuel dosage, the products transformed from granular aggregates of cubic Co3O4 into a mixture of cubic Co3O4 and tetragonal CoO with fluffy sheet morphologies. Electrochemical measurements indicated that the products (Co3O4) showed a capacitance up to 179.7 F·g−1 (at 0.2 A·g−1) when the citric acid/Co(NO3)2·6H2O molar ratio was 7/27. Significantly, the capacitance could be further improved by 102% (362.8 F·g−1 at 0.2 A·g−1) after annealing at 350°C for 3h under nitrogen atmosphere. This annealed sample also demonstrated decent rate performance (285.7 F·g−1 at 4 A·g−1) and cycling stability (73.5% retention after 1000 cycles). The current study suggests that this process has promise in large-scale production of electrode materials for supercapacitors.
The performance of lithium manganese phosphate as a lithium-ion battery cathode material is improved by collective and cooperative strategies including Fe substitution, carbon coating, and the assembly of carbon-coated LiMn1−x Fe x PO4 nanocrystals into a highly dense packing of monodisperse microboxes. These strategies are implemented experimentally by a facile and scalable synthesis method. The dense packing allows the conductive carbon coating to be interconnected into a continuous three-dimensional network for electron conduction. The porosity in the packed structure forms the complementary network for Li+ transport in the electrolyte. The primary particles are nanosized and Fe-substituted to improve the effectiveness of Li+ insertion and extraction reactions in the solid phase. The reduction of transport resistance external and internal to the nanocrystals yields a Li storage host with good rate performance (116 mAh g−1 at 5 C discharge rate where C = 170 mA g−1) and cycle stability (95% retention of initial capacity in 50 cycles). Electrochemical impedance spectroscopy and morphology examination of the cycled microboxes reveal a robust packed structure with stable surfaces.
The coupling of electrochemical processes and ultrasound has found a larger number of applications during the past years. Especially in the field of materials science and energy technology its potential for the production of nanomaterials, improved metals, alloys and composites is noteworthy. In this paper the focus is on fundamental studies applying the electrochemical quartz crystal microbalance technique in order to improve understanding of these sonoelectrochemical processes. Three examples from the work of the authors in the area are presented: A study of the modification of the electrodeposition of Cu from chloride-based electrolytes by ultrasound, the deposition of metal/ceria composites from electrolytes low in ceria content, and the deposition of metal nanoparticles for decoration of solid oxide fuel cell anode powders. In the first two examples the electrochemical quartz crystal microbalance technique is applied in situ, whereas in the latter example it was used to study the electrochemistry of the systems involved.
The aim of this work is to develop and evaluate a mathematical model for the process of storing hydrogen obtained from hydroelectricity via electrolysis, for use as an energetic vector in rural areas of Venezuela. Following an exhaustive bibliographical review of the subject, pressurized containers were chosen as the most appropriate means of storage. The components of the compressed H2 gas storage systems to be modelled are 1) the Compression Unit, CU, and 2) the Storage Unit, SU. With this information and by using non-linear regression methods, we developed a mathematical model with which to study the behaviour of the main variables involved in the storage process: the quantity of H2 to be stored, the storage pressure, energy consumption, the size of the compressor, and the unit cost of the containers. In structural terms, the mathematical model comprises an energy model and a financial model. The results show that there is a range of operating conditions with a minimal overall cost, as a result of the behaviour of the investment cost, which define how the total costs evolve.
This work describes a route for processing the electroactive components of spent zinc–MnO2 dry cells via fusion with potassium hydrogenosulfate (KHSO4). The fused mass was dissolved in water. Lead remained in the insoluble matter. Soluble zinc and manganese were isolated by a two-step precipitation procedure. Zinc was precipitated as oxalate after addition of aqueous H2C2O4 at pH around 1. Manganese was isolated as MnO(OH)2 after adjusting pH at 11 using aqueous KOH + H2O2. pH control is essential for a successful separation of the elements. Both were recovered in high yields (>92 wt.%). About 75 wt.% of potassium was recovered as K2SO4 after treatment of the final effluent with sulfuric acid (pH 7) followed by slow evaporation.
To optimise the choice of the compounds for a selected application, a better understanding of the role of each alloy constituent on the electronic properties of the material is crucial. In this work, we study experimentally the electronic properties of nanocrystalline and polycrystalline (Mg1− xMx )2Ni, (Mg1− xMx )2Cu, La(Ni1− xMx )5, and Ti(Ni1− xM′ x ) (M Mn,Al; M′Fe,Mg,Zr) alloys. The nanocrystalline and polycrystalline samples were prepared by mechanical alloying (MA) followed by annealing and arc melting method, respectively. All X-ray photoelectron spectroscopy (XPS) spectra were measured immediately after cleaning of the sample surface in a vacuum of 8×10−11 mbar. Furthermore, we have measured XPS spectra of in situ prepared nanocrystalline and polycrystalline LaNi5, TiNi, and Mg2Ni thin films and compared with those obtained for ex situ prepared bulk materials. The substitution of Mg in Mg2Ni and Mg2Cu, Ni in LaNi5 and TiNi by transition metals leads to significant modifications of the shape and width of the valence band of the nanocrystalline as well as polycrystalline samples. Especially, the valence bands of the MA nanocrystalline alloys are considerably broader compared to those measured for the polycrystalline samples. Results also showed that the strong modifications of the electronic structure of the nanocrystalline alloys could significantly influence on their hydrogenation properties.