batterydata/paper-abstracts huggingface dataset:
Adolescence is a unique time where the transition from childhood into adulthood takes place. Despite the dramatic changes in physical, emotional and cognitive domains that are likely to impact stuttering treatment, adolescents’ response to stuttering treatment is not well documented. The Michael Palin Centre provides an intensive two-week therapy programme for adolescents who stutter. This programme consists of three components including speech management skills, cognitive behavioural therapy, and communication skills training. The overarching goal of this programme is to reduce overt and covert symptoms of stuttering. This poster presents data from a group of adolescents who stutter who attended the programme during a 3-year time period (2008-2010). Data will be presented from 38 adolescents who attended the intensive programme. All were between the ages of 16;0-18;11. This is a longitudinal study that measures stuttering severity (SSI-3), frequency (%SS) and a battery of self-report questionnaires over a 12-month period. Stuttering frequency measures were taking from videos the adolescents made at home during reading and in conversation. Questionnaires were completed at eight time points during the programme were taken and include a pre-therapy baseline, treatment initiation, treatment conclusion, and at 5 follow-up sessions. Preliminary results have been completed for the first four measures. For stuttering frequency, there is no change during the two-month baseline before therapy. After the intensive treatment there is a reduction in stuttering frequency in reading. This reduction in stuttering frequency is maintained over a 5-week follow up period. A similar pattern emerged for stuttering severity with stuttering severity not changing during the baseline, but reducing immediately after treatment and maintaining 5 weeks after treatment. A full analysis of the maintenance of stuttering frequency and severity over the long-term will be presented as well as an analysis of the results from the self-report questionnaires.
LiNi0.6Co0.2Mn0.2O2 cathode materials were synthesized from spherical and homogeneous mixed metal hydroxide Ni0.6Co0.2Mn0.2(OH)2 which was prepared by co–precipitation method. The synthetic conditions of the metal hydroxide, such as pH, amount of chelating, stirring speed, temperature, etc. were studied in detail. The homogeneous and spherical Ni0.6Co0.2Mn0.2(OH)2 precursor obtained in the optimized synthetic conditions had a high tap–density of 1.94gcm−3. A well–ordered layer–structured and spherical LiNi0.6Co0.2Mn0.2O2 cathode material, with the tap–density of 2.59gcm−3, was fabricated by calcinating the as-prepared Ni0.6Co0.2Mn0.2(OH)2 precursor and 5% excess LiOH·H2O at 820°C in the flowing oxygen. The crystal structure, morphology and electrochemical properties of the precursors and final products were investigated by using X–ray diffractometry, scanning electron microscopy, charge–discharge test and C–V method. In the voltage ranges of 2.8–4.3, 4.4 and 4.5V, the initial discharge capacities of LiNi0.6Co0.2Mn0.2O2 at 1 C rate were 172.1, 177.9 and 182.5 mAh g−1, respectively, while the corresponding discharge capacity retention ratios after 100 cycles were 94.3%, 90.7% and 85.4%. For elevated temperature operation (60°C), the resulted capacity was as high as 196.9mAh g−1 in the voltage range of 2.8–4.3V and retained 89.7% after 100 cycles.
Guided rehabilitation beyond 6-months is rare following anterior cruciate ligament reconstruction (ACLR), despite high prevalence of unacceptable symptoms and quality of life (QoL). Our primary aim was to determine the feasibility of a randomised controlled trial (RCT) evaluating a physiotherapist-guided intervention for individuals 1-year post-ACLR with persistent symptoms. Our secondary aim was to determine if a worthwhile treatment effect could be observed for the lower-limb focussed intervention (compared to the trunk-focussed intervention), for improvement in knee-related QoL, symptoms, and function.
Palladium-based alloy materials as cathodes for the reduction of oxygen are regarded as potential substitutes for platinum-based catalysts in fuel cells. In this work, we present a scientometric analysis and critically review the use of Pd alloys for the oxygen reduction reaction (ORR). Through scientometric analysis, publication information, research fronts and hotspots are identified. For the critical review, reaction mechanisms in different media are discussed, with the aid of volcano plots to show the general principles for catalyst modifications to maximise the ORR. Influencing factors, including alloying, structure, strain and ligands, particle size, crystal facets and dealloying are considered with a view to informing the theoretical feasibility to enhance the ORR activity. In addition, Pd-based alloys synthesized by different methods are presented and compared in terms of ORR activities. Future research directions are discussed and possible approaches to mass production for industrialization are also proposed.
Ultrafine Fe2O3 nanorods anchored on graphene oxide (GO) are synthesized by a one-pot route under mild conditions in presence of KMnO4 and Ni foam. Ni foam is beneficial for the formation of Fe2O3 rather than FeOOH under otherwise the same conditions, while KMnO4 accelerates the hydrolysis of FeCl3, which promotes the nucleation of Fe2O3 and the achievement of uniform ultra-small morphology thereby. As an anode material for lithium-ion batteries, the Fe2O3/GO manifests a reversible capacity of 1004 mA h g−1after 500 cycles at 200 mA g−1, and even presents a high reversible capacity of 722 mA h g−1 at 1600 mA g−1. The excellent electrochemical properties of Fe2O3/GO are attributed to the ultrafine nanorods of Fe2O3 and the strong interaction between Fe2O3 and GO, which can reduce the diffusion distance of Li+ ions, enlarge the electrode/electrolyte contact area and improve the cyclic stability of iron oxide.
The post-Cold War era has witnessed considerably reduced national defense budgets and a consequent decline in the international arms trade. Therefore, the world’s arms suppliers have begun to sell high-performance weapons as another means of acquiring additional foreign exchange, thus enabling newly industrialised countries (NICs) to procure relatively advanced weaponry at lower prices. This trend is driving defense procurement policies in NICs toward purchasing arms from abroad. This development is impeding the growth of independent R&D capabilities, even causing rapid deterioration, and thus hindering further defense technology development (DTD). Hence, developing a policy to counter this change is an urgent requirement for NICs. This study analyzes the characteristics of DTD and development trends in advanced nations, and then uses system dynamics theory to construct a framework for developing defense technology in Taiwan.
The use of conductive carbon scaffolds is efficient and effective to obtain advanced composite cathodes for lithium–sulfur batteries. However, the loading amount of mostly less than 70 wt% induces a limited energy density and the typical fabrication route involving high-temperature and elaborate process also limits the manufacturability of sulfur cathode, both of which hinder the practical application of lithium–sulfur batteries. Herein, a scalable, room-temperature, and one-step method is employed for carbon nanotube (CNT)/sulfur composite cathode, in which aligned CNTs served as interconnected conductive scaffolds to accommodate sulfur. When the loading amount of sulfur increased from 50 to 90wt%, the tap density of CNT/sulfur increased from 0.4 to 1.98gcm−3, and the mass/areal/volumetric capacities of the whole electrodes (CNT/sulfur composites and binders) was improved from 500.3mAhg−1/0.298 mAhcm−2/200.1mAhcm−3 to 563.7mAhg−1/0.893 mAhcm−2/1116.0mAhcm−3, respectively. The rise of sulfur content in the composite cathode renders a dramatic increase of the energy density of lithium–sulfur cells. The ultra-high loading amount of sulfur is attributed to the open, ordered, straight pore structure of aligned CNT scaffolds for the uniform distribution of fine sulfur particles. The robust sp2 carbon frameworks served as rapid pathways for electron transfer, and the large aspect ratio, good alignment, ordered packing of individual CNT in small bundles offer a low conductive percolation threshold. Consequently, the sulfur with a high loading content was efficiently utilized for a lithium–sulfur cell with a much improved energy density.
The availability of safer electrolytes is an important target in the development of the new lithium batteries. The use of Li-doped mixtures based on ionic liquids and organic carbonates seems to be a very promising approach, because it allows to balance the non-flammability, high conductivity, low viscosity and good electrochemical stability. Here, we reported on the characterization of electrolytes solutions based on N-methoxyethyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)-imide (PYR1,2O1TFSI), EC/DEC binary system and LiTFSI, as potential safe electrolytes for lithium batteries. The mixtures were studied in terms of flammability tests, thermal features, physical properties, namely conductivity and viscosity, and electrochemical performances. We also carried out a comparison with the pure IL–Li salt system as well as with the standard electrolyte 1.0 M LiPF6 EC–DEC. The best solution showed ionic conductivity exceeding 7 mS cm−1 at 20 °C, room temperature viscosity lower of about 25 cPs and an overall electrochemical window of 4.5 V. With respect to the pure LiTFSI–IL electrolyte, a very stable interface with Li anode was also observed in at least for 20 storage days. This mixture was tested in a LiFePO4-based cell, and showed good performances at 1 C, assuring electrochemical stability for about 250 cycles with ∼100% efficiency.
Most of the research on psychopathology has provided an incomplete picture of mental health by focusing on vulnerability factors and omitting the transversal processes that may explain human adapted functioning. Moreover, research has not sufficiently addressed prospective protective factors for mental health. New theoretical and empirical endeavors aim to incorporate this perspective, particularly in the realm of emotional disorders. A positive view of the future is an indispensable process in attaining desired goals and wellbeing. Openness to the Future is a construct characterized by positive affectivity towards the future, which can be a protective factor for mental health. Although some scales assess future orientations, the complexity of this concept has not yet been captured; therefore, there is a need for new instruments. This study presents the development and validation of a scale for measuring Openness to the Future in clinical (n = 412) and community (n = 890) samples.
Here, we report a chemical process for the preparation of nano-carbon coated LiVPO4F cathode material for lithium ion batteries. V2O5 powders are first lithiated in the mixture of LiF, NH4H2PO4 and oxalic acid at room temperature and then form an amorphous Li-V-P-O-F precursor by ball milling, which is subsequently converted to LiVPO4F by a short postannealing. X-ray photoelectron spectroscopy (XPS) results reveal that the V5+ in the Li-V-P-O-F precursor is reduced to V3+ by oxalic acid at room temperature. X-ray diffraction results show that the LiVPO4F sample is triclinic structure. TEM image indicates the LiVPO4F particles are about 100nm in diameter and wrapped by nano-carbon webs. The LiVPO4F/C composites synthesized at 500°C for 2h deliver a discharge capacity of 143mAhg−1 at 0.5C in the range of 3.0–4.4V at the first cycle, and possess a favorable capacity cycling maintenance at the 0.5C, 1C and 3C rates.
Three electroanalytical techniques have been used to study the solid-state ionic diffusion of lithium into cerium–vanadium mixed oxide thin films, i.e. potentiostatic intermittent titration technique, galvanostatic intermittent titration technique and electrochemical impedance spectroscopy. Diffusion coefficients measured with the above mentioned techniques show a non-monotonic decay between 8×10−12 and 8×10−14 cm2 s−1. In particular, lithium diffusion coefficient drops by more than one order of magnitude at lithium intercalation degree x=0.6. This abrupt change seems to be related to a dramatic increase of the material resistance suggesting that the limiting factor in atomic lithium diffusion may be the low electronic conductivity.
Aluminum–air (Al–air) battery is one of the most promising candidates for next-generation energy storage systems because of its high capacity and energy density, and abundance. The polyacrylic acid (PAA)-based alkaline gel electrolyte is used in all-solid-state Al–air batteries instead of aqueous electrolytes to prevent leakage. The optimal gel electrolyte exhibits an ionic conductivity of 460 mS cm−1, which is close to that of aqueous electrolytes. The Al–air battery peak capacity and energy density considering only Al can reach 1166 mAh g−1-Al and 1230 mWh g−1-Al, respectively, during constant current discharge. The battery prototype also exhibits a high power density of 91.13 mW cm−2. For the battery is a laminated structure, area densities of 29.2 mAh cm−2 and 30.8 mWh cm−2 are presented to appraise the performance of the whole cell. A novel design to inhibit anodic corrosion is proposed by separating the Al anode from the gel electrolyte when not in use, thereby effectively maintaining the available capacity of the battery.
The increasing demand for high-specific-energy batteries drives researchers to revisit Li metal anode. However, the formation and growth of Li-dendrite possibly leads to short-circuit of the battery, causing safety hazard of Li metal batteries. Therefore, it is quite necessary to regulate the plating/stripping behaviors of Li metal anodes to address this long-standing issue. Herein, we report the regulation of Li plating/striping behavior via manipulating the ratio of oxygen containing groups on reduced graphene oxide papers. It has been revealed that the electrochemical properties are highly dependent on the amount of carbonyl CO groups, which could associate Li+ and serve as a uniform nucleation site to guide Li plating. Furthermore, a high lithium ion diffusion coefficient of ∼2.09 × 10−14 m2 s−1 was enabled, around one magnitude higher than that of the Li lattice self-diffusivity (∼2 × 10−15 m2 s−1). As a result, stable dendrite-free Li metal anode is realized on the reduced graphene oxide paper with high CO group content (8.4%), which exhibits a low and stable overpotential of 50 mV for a long lifetime of 400 h. Our studies provide a fresh insight into the Li ion diffusion and its critical role in the regulation of the Li plating/stripping behaviors.
Accurately predicting the future capacity and remaining useful life of batteries is necessary to ensure reliable system operation and to minimise maintenance costs. The complex nature of battery degradation has meant that mechanistic modelling of capacity fade has thus far remained intractable; however, with the advent of cloud-connected devices, data from cells in various applications is becoming increasingly available, and the feasibility of data-driven methods for battery prognostics is increasing. Here we propose Gaussian process (GP) regression for forecasting battery state of health, and highlight various advantages of GPs over other data-driven and mechanistic approaches. GPs are a type of Bayesian non-parametric method, and hence can model complex systems whilst handling uncertainty in a principled manner. Prior information can be exploited by GPs in a variety of ways: explicit mean functions can be used if the functional form of the underlying degradation model is available, and multiple-output GPs can effectively exploit correlations between data from different cells. We demonstrate the predictive capability of GPs for short-term and long-term (remaining useful life) forecasting on a selection of capacity vs. cycle datasets from lithium-ion cells.
To achieve higher energy density and power density, we have designed and fabricated a symmetric redox supercapacitor based on microelectromechanical system (MEMS) technologies. The supercapacitor consists of a three-dimensional (3D) microstructure on silicon substrate micromachined by high-aspect-ratio deep reactive ion etching (DRIE) method, two sputtered Ti current collectors and two electrochemical polymerized polypyrrole (PPy) films as electrodes. Electrochemical tests, including cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatical charge/discharge methods have been carried out on the single PPy electrodes and the symmetric supercapacitor in different electrolytes. The specific capacitance (capacitance per unit footprint area) and specific power (power per unit footprint area) of the PPy electrodes and symmetric supercapacitor can be calculated from the electrochemical test data. It is found that NaCl solution is a good electrolyte for the polymerized PPy electrodes. In NaCl electrolyte, single PPy electrodes exhibit 0.128Fcm−2 specific capacitance and 1.28mWcm−2 specific power at 20mVs−1 scan rate. The symmetric supercapacitor presents 0.056Fcm−2 specific capacitance and 0.56mWcm−2 specific power at 20mVs−1 scan rate.
Crystalline LiFePO4 has been synthesized using solid-state, spray pyrolysis, and wet chemical methods. The crystal parameters were obtained from Rietveld’s refinement methods of the X-ray diffraction patterns. A detailed investigation of the Fe valency carried out using Mössbauer spectroscopy at room temperature indicates that Fe is predominantly present in its bivalent state.
To evaluate the partitioning of net radiation (Rn) and actual evapotranspiration (ETa), measurements of Rn, sensible heat flux (H), soil heat flux (G), latent heat flux (LE), reference evapotranspiration (ETo), transpiration (Tp) and soil evaporation (Es) were taken during the 2009/2010 and 2010/2011 growing seasons on a flat and uniform olive (cv. Arbequina) orchard, located in the Pencahue Valley, Región del Maule, Chile (35°23′ LS; 71°44′ LW; 96 m above sea level). Olive trees were trained on a triangular hedgerow system with a plant density of 1333 trees ha−1 (superintensive). An eddy covariance system, sapflow sensors and microlysimeter were used to measure ETa, Tp and Es, respectively. Results indicated that the eddy covariance measurements showed a lack of the energy balance closure of 12.8 %. Values of LE, H and G were between 28–47, 34–68 and 2–6 % of Rn, respectively, while ratios of Tp and Es to ETa ranged between 0.64–0.74 and 0.26–0.36, respectively. During two growing seasons, the single crop coefficient (Kc = ETa/ETo) was between 0.27 and 0.66, while the dual crop coefficient (Tp/ETo + Es/ETo) ranged between 0.26 and 0.56. According to these results, H and Tp were the main component of Rn and ETa, respectively, for the particular conditions of the drip-irrigated olive orchard with a fractional cover of 30 % and wetted area of 4.5 %.
Lithium-ion batteries are widely adopted as the power supplies for electric vehicles. A key but challenging issue is to achieve optimal battery charging, while taking into account of various constraints for safe, efficient and reliable operation. In this paper, a triple-objective function is first formulated for battery charging based on a coupled thermoelectric model. An advanced optimal charging strategy is then proposed to develop the optimal constant-current-constant-voltage (CCCV) charge current profile, which gives the best trade-off among three conflicting but important objectives for battery management. To be specific, a coupled thermoelectric battery model is first presented. Then, a specific triple-objective function consisting of three objectives, namely charging time, energy loss, and temperature rise (both the interior and surface), is proposed. Heuristic methods such as Teaching-learning-based-optimization (TLBO) and particle swarm optimization (PSO) are applied to optimize the triple-objective function, and their optimization performances are compared. The impacts of the weights for different terms in the objective function are then assessed. Experimental results show that the proposed optimal charging strategy is capable of offering desirable effective optimal charging current profiles and a proper trade-off among the conflicting objectives. Further, the proposed optimal charging strategy can be easily extended to other battery types.
In automotive and stationary Li-ion battery packs, a large number of individual cells, typically hundreds to thousands of cells, are electrically connected to achieve pack specification. These large number of interconnections are mainly achieved by welding cell tab to bus-bar using a welding technique of choice. Ultrasonic metal welding (UMW) is one of the common joining technique employed to join pouch cell’s tabs to bus-bar. Although commonly employed, there is little research currently exist in literature reporting the joint characteristics in terms of electrical resistance and temperature raise due to charge-discharge current. Li-ion batteries reaching sub-milliohm internal resistance, risks the temperature raise at the joint could be even higher than the cell itself which raise a serious safety concern and they are to be addressed. This research investigates the electrical and thermal characteristics of ultrasonic joints of 0.3 mm aluminium/nickel coated copper tabs to 1.0 mm copper bus-bar. This article reports the dynamic behaviour of electrical resistance and corresponding temperature increase as a result of current flow. To capture the electrical and thermal behaviour of the joint, a numerical model has been developed and validated with experimental results, which can be employed to analyse battery pack performance.
Perfluorosulfonic-acid (PFSA) ionomers are widely used as solid electrolytes and ion-exchange membranes in electrochemical devices, wherein their properties are impacted by the interactions among the anionic sulfonate groups, mobile counter-ions (cations), and hydration levels. Cation-form and humidity collectively affect the structure/transport-property relationship, yet their interplay is still not well known. In this paper, we report changes in water uptake and conductivity of cation-exchanged PFSA in both vapor and liquid water, which are then correlated with changes in mechanical properties and nanostructure (hydrophilic-domain spacing and phase-separation). It is found that the magnitude of changes depends significantly on the membrane water content, with master curves in terms of water volume fraction and water per charge realized. Moreover, membrane nanostructure and dynamical-mechanical behavior is examined to establish structure/transport and transport/stability relationships. It is found that with increasing cation size (radius) and valence, the storage modulus increases, while the water uptake and conductivity decrease. In addition, regardless of the cation type, a universal relationship is found between the conductivity and modulus, indicative of a transport/stability tradeoff. The extent to which the cations impact the transport properties depends on the water content: at low hydration levels the controlling factor is the cation (and its interaction with the sulfonate sites), at increasing hydration the dominant factor becomes water volume fraction, although it is also controlled by the cations. Similarly, the decrease in hydrophilic domain spacing of PFSA exchanged with larger cations scales with cation radius at low water contents, but with Lewis acid strength (LAS) at higher hydration levels. The findings reported here not only provide valuable insights into the interaction between sulfonate groups, cations, and water surrounding these ionic groups, but also for understanding cation contamination in fuel cells and redox flow batteries.