batterydata/paper-abstracts huggingface dataset:
As a promising nanoenergy technology to harvest mechanical energy from environment, triboelectric nanogenerator (TENG) has attracted much attention and various strategies focused on optimization of triboelectric materials have been proposed to further improve its output power density. This work focuses on the electrode material for improvement of TENGs. A commercial double-sided conductive carbon tape composed of carbon powder is proposed as the electrodes for TENGs, based on which a superior performance TENG comprised of spin-coated flat polydimethylsiloxane (PDMS) and polyamide-6 (PA6) films is fabricated. Owing to the strong additional interaction between carbon electrode and tribo-layer, a 20 × 20 mm2 carbon-PDMS/PA6 TENG demonstrates a peak output voltage of ~ 1760 V, a short-circuit current density of ~ 240 mA m−2, and a maximum power density of ~ 120 W m−2, much higher than those of aluminum electrode-based Al-PDMS/PA6 TENGs. Detailed investigations reveal that the dramatically enhanced performance originates from the additional interaction in the pores between coarse carbon electrode and PDMS film, and from the enhanced electric negative polarity of PDMS films with the peeling and transferring treatment. This study provides a promising simple and low-cost strategy of selecting and preparing electrode materials with special micro/nanostructures to interact with triboelectric layers to generate additional triboelectric charges for high performance TENGs.
The influence of the lithium inventory on the performance and degradation mechanism of NCA||Si cells operating at a third of the theoretical silicon capacity is analysed. The lithium inventory was increased by electrochemical prelithiation to a value of 300 mAhg−1 (Si). Full-cells were cycled at harsh conditions with a cut-off of 4.4 V to maximise the capacity. The higher lithium inventory resulted in an increased reversible capacity from 163 to 199 mAhg−1(NCA). The cycle-life was increased by 60% and reached 245 cycles. Three-electrode and post-mortem analyses revealed that the main reason for capacity fade is repeated SEI repair, consuming the lithium inventory. Differential capacity analysis revealed different degradation of silicon anodes cycled in half-cells compared to full-cells. No shifts in the alloying/dealloying peaks are present in full-cell geometry while changes are observed in half-cell geometry. This is expected to be caused by a limited alloying capacity in the full-cell and lithium consumption during cycling, alleviating material stresses. We conclude that the lithium consumption is the main factor causing capacity fade in NCA||Si cells. The decreasing degree of lithiation over cycling due to the lithium consumption is likely to be the reason for the absence of structural degradations of full-cell cycled silicon.
This paper describes the development of a simulation model for predicting the performance of a solar photovoltaic (PV) system under specified load requirements and prevailing meteorological conditions at the site location. This study is aimed at situations where the loads are provided by alternating current (AC) electrical devices. The model consists of several submodels for each of the main components of the PV system; namely, PV array, battery, controller, inverter and various loads. Mathematical equations developed for modeling the performance of each component are explained along with the methodology to determine the performance coefficients. In order to validate the developed simulation model, an experimental system has been set up and tested under a variety of climatic conditions. Simulated results from the model under the same operating and environmental conditions are compared with those observed from the experimental tests. Good agreement is found in the comparison. Slight discrepancies appearing in the results are described and recommendations are given for further improvement. The simulation model developed can be used not only for analyzing the PV system performance, but also for sizing the PV system which is most suitable to the load requirements at any specified location provided that the local meteorological data is available.
The Ruff Figural Fluency Test (RFFT; a pencil and paper test) and the CogState (a computerized cognitive test battery) are well-validated and suitable tests to evaluate cognitive functioning in large observational studies at the population level. The LifeLines Cohort Study includes the RFFT as baseline measurement and incorporated the CogState as replacement for the RFFT at follow-up. It is unknown how these two tests relate to each other. Therefore, the aim of this study is to examine the correlation between the RFFT and the CogState and the impact of demographic characteristics on this association.
This paper presents the results on the spatio-temporal variation in vine transpiration at the scale of a vineyard and derives a simple model relating daily vine transpiration to soil water storage. An experiment was conducted during summers of 1994 and 1995 in a 1ha vineyard of Southern France in which five monitoring plots had been installed. In each plot, soil moisture was monitored with neutron probes down to 260cm under the row and between the rows to take into account the heterogeneity of the rooting system. Transpiration was monitored by the stem heat balance method on two vinestocks per plot. The soil water retention characteristics were measured on undisturbed samples with a pressure plate extractor. With decreasing soil water availability, vines react similarly to most crops: in a first stage up to mid-July transpiration remains at a maximum and in a second stage transpiration is reduced due to soil water depletion. Although there is a large variation in the transpiration intensity between vinestocks, the temporal variation of transpiration is predominantly similar over the vineyard. This justifies a uniform modelling approach to simulating vineyard transpiration. Accordingly, we derived a bilinear relationship relating the ratio between the actual transpiration and the potential transpiration of the vineyard to the field average soil water storage. The parameters of the relationship could be related to laboratory determined values of soil moisture content at −0.1 and −1.5MPa.
Renewable energy generation is rapidly growing in the power sector industry and widely used for two categories: grid connected and standalone system. This paper gives the insights about fuel cell operation and application of various power electronics systems. The fuel cell voltage decreases bit by bit with expansion in current because of losses associated with fuel cell. It is difficult in handling large rated fuel cell based power system without regulating mechanism. The issue connected with fuel based structural planning and the arrangements are widely investigated for all sorts of utilization. In order to improve the reliability of fuel cell based power system, the integration of energy storage system and advanced research methods are focused in this paper. The control algorithms of power architecture for the couple of well-known applications are discussed. Additionally, the paper addresses the suitable processor utilized as a part of the energy unit application on the premise of fuel cell characteristics. In this paper, the challenges to improve the dynamics of controller in fuel cell based applications are mentioned.
Sn-based materials have drawn great attention as anodes for rechargeable batteries because of their extremely high theoretical energy storage capacities. Herein, a nanocomposite based on SnF2 and acetylene black is proposed as a high-performance anode material for sodium-ion batteries and their electrochemical performances, as well as related energy storage mechanism, are investigated. The nanocomposite electrode delivered a high reversible capacity of 563mAhg−1 which is considerably improved compared to a reversible capacity of 323mAhg−1 of the micron-sized bare SnF2 electrode. The nanocomposite electrode shows superior rate capability and delivers a reversible capacity of 191mAhg−1 at a high current density of 1C, while the bare electrode delivers negligible capacities. The changes in crystallographic structure are observed using in-situ XRD and the results reveal the existence of a solid solution of two or more species during dis/charging. The electronic and atomic configurations depending on the state of dis/charging are systematically investigated using ex-situ X-ray absorption spectroscopy. The results reveal that the valence change of Sn follows the conversion (SnF2 + 2Na → Sn + 2NaF) and alloying (Sn + XNa → SnNaX) reaction upon sodium insertion into a composite.
The miniaturization of rechargeable lithium-ion batteries requires high quality thin-film electrodes. Electrostatic spray deposition (ESD) technique was used to fabricate LiMn2O4 thin-film electrodes with three different morphologies: sponge-like porous, fractal-like porous, and dense structures. X-ray diffraction (XRD) and scanning electron microscopy were used to analyze the structures of the electrodes. These electrodes were made into coin cells against metallic lithium for electrochemical characterization. Galvanostatic cycling of the cells revealed different rate capability for the cells with LiMn2O4 electrodes of different morphologies. It is found that the cells with LiMn2O4 electrodes of porous, especially the sponge-like porous, morphology better rate capability than those with dense LiMn2O4 electrodes. Electrochemical impedance spectroscopy (EIS) study indicates that the large surface area of the porous electrodes should be attributed to the smaller interfacial resistance and better rate capability.
The aim of this prospective study was to investigate the effects of pregnancy on eating disorders (ED), dietary habits and body image perception. One hundred and fifty pregnant women were interviewed between the period January 2001 and May 2003. Ninety-seven women completed the study and were divided in three subgroups: pregnant women with a positive history of dieting (n=37), pregnant women with a positive history of dieting with a complete diagnosis of a current ED (n=11) and pregnant women with a negative history either of dieting or ED (control group; n=49). Age, education and parity were equally distributed in all three groups. To verify if pregnancy exerts a specific protective effect, a battery of psychometric tests was administered to women at 12° (T0), 22° (T1), and 34° pregnancy weeks (T2), and 2 days (T3) and 4 months (T4) after delivery, respectively. The study showed a quadratic trend for ED, subthreshold ED and body satisfaction, with a general improvement in the middle of pregnancy and a return to previous levels after delivery. Some interesting significant differences came out among the groups.
Owing to their potential for greater safety, higher energy density, and scalable fabrication, bulk-type all-solid-state lithium-ion batteries (ASLBs) employing deformable sulfide superionic conductors are considered highly promising for applications in battery electric vehicles. While fabrication of sheet-type electrodes is imperative from the practical point of view, reports on relevant research are scarce. This might be attributable to issues that complicate the slurry-based fabrication process and/or issues with ionic contacts and percolation. In this work, we systematically investigate the electrochemical performance of conventional dry-mixed electrodes and wet-slurry fabricated electrodes for ASLBs, by varying the different fractions of solid electrolytes and the mass loading. This information calls for a need to develop well-designed electrodes with better ionic contacts and to improve the ionic conductivity of solid electrolytes. As a scalable proof-of-concept to achieve better ionic contacts, a premixing process for active materials and solid electrolytes is demonstrated to significantly improve electrochemical performance. Pouch-type 80 × 60 mm2 all-solid-state LiNi0 · 6Co0 · 2Mn0 · 2O2/graphite full-cells fabricated by the slurry process show high cell-based energy density (184 W h kg−1 and 432 W h L−1). For the first time, their excellent safety is also demonstrated by simple tests (cutting with scissors and heating at 110 °C).
Climate measurements are needed at a scale at which organisms live and die. Currently available climate sensors, however, are not well suited for long-term field measurements at such a scale. We have therefore developed a new temperature and moisture logger, the Temperature-Moisture-Sensor (TMS), which we designed for a wide range of ecological applications. The device mimics a small herbaceous plant. Its belowground part houses a patented, proprietary soil moisture sensor working on the time-domain transmission principle. Air, surface and soil temperatures are measured simultaneously by three independent sensors. The TMS data logger has a large memory and long battery life, so it is suitable for taking long-term microclimate measurements in the field. With a data acquisition interval of 15 min, it has sufficient memory to last for almost 15 years. We have thoroughly tested the TMS logger both in the laboratory and in demanding field conditions ranging from tropical rain forests of Africa to high-elevation cold deserts of the Himalayas. The device has provided microclimate measurements in a wide range of environmental conditions and has also performed well in controlled laboratory settings. The key added value of the TMS logger is that it concurrently measures soil moisture as well as soil, surface and air temperature at a biologically relevant scale. It is also able to continuously measure the microclimate for several years even in the most extreme conditions. The device can therefore be used to build extensive tailored field measurement networks providing crucial data about microclimate conditions shaping biological processes in the face of climate change.
A nanostructured conducting copolymer poly(aniline-co-o-aminophenol) (PANOA) was electrochemically synthesized on a glassy carbon (GC) electrode and its redox and anion exchange properties for perchlorate removal were investigated by cyclic voltammetry, FTIR, and X-ray photoelectron spectroscopy (XPS). Results from cyclic voltammograms in a wide range of solution pHs showed that this conducting polymer had a good redox electrochemical stability and reversibility. FTIR spectra demonstrated that ClO 4 - ions were immobilized in the copolymer film after its oxidation in a solution containing NaCl and NaClO4. The result of XPS spectra showed that the copolymer films oxidized in a solution containing 0.10M NaCl and 0.010M NaClO4 at pH 5.7 and 9.0 had ClO 4 - / Cl - molar ratio of 0.53 and 0.31, respectively, which were significantly higher than the ratio of 0.10 in the tested aqueous solution. The results, thus, indicated that the PANOA copolymer can be used to develop an electrically controlled anion-exchange process to remove perchlorate from the industrial wastewaters. This would be an environment-friendly green process, as it does not face the brine disposal problem, as encountered in traditional ion-exchange processes that required uses of regenerative agents.
This study focuses on the role of the aquifer media as a tool to improve the characteristics of seawater used to supply desalination plants, quantifying this improvement from a considerable number of physicochemical parameters. The evolution of both physicochemical and microbiological characteristics through the aquifer media has been determined by comparing the composition of seawater samples taken via direct intake with those taken over the aquifer. The principal improvements are due to the process of filtration. It includes up to a 95 % reduction in turbidity and up to a 50 % reduction in SDI. Other parameters are also notably reduced (TOC is cut on average by 60 %, and DO by 80 %), due to bacterial activity in the aquifer. It is also important to highlight that only a short distance of water flow through the aquifer is needed to achieve this improvement. If it used the seabed as the filter material, it would be necessary a minimum thickness of a few meters due to biological activity involves a significant increase in the TOC. An understanding of the filtration processes occurring within the aquifer provides a natural analogue on which future improvements in artificial pre-treatment can be based.
Precisely battery state of health estimation and remaining useful lifetime prediction are crucial factors in ensuring the reliability and safety for system operation. This paper thus focuses on the short-term battery state of health estimation and long-term battery remaining useful lifetime prediction. A novel hybrid method by fusion of partial incremental capacity and Gaussian process regression is proposed and dual Gaussian process regression models are employed to forecast battery health conditions. First, the initial incremental capacity curves are filtered by using the advanced signal process technology. Second, the important health feature variables are extracted from partial incremental capacity curves using correlation analysis method. Third, the Gaussian process regression is applied to model the short-term battery SOH estimation using the feature variables. Forth, an autoregressive long-term battery remaining useful lifetime model is established using the results of battery SOH values and previous output. The predictive capability and effectiveness of two models are demonstrated by four battery datasets under different cycling test conditions. Otherwise, the robustness of the two models is verified using four datasets with different health levels. The experimental results show that the proposed method can provide accurate battery state of health estimation and remaining useful lifetime.
Practical screening strategies are necessary to detect neurocognitive impairment of all severities in HIV populations, which remains prevalent despite highly active antiretroviral therapy and requires full neuropsychological testing for diagnosis. We aimed to develop a brief and clinically feasible battery to screen for HIV-associated neurocognitive disorders (HAND) in resource-limited settings even where English is not the native language.
Chitosan with hydroxyapatite composition, a natural polymer, may be a biomaterial of importance for bone regeneration. Carbon nanotube, a nanoscale material, has been another focus for bone restoration. Zinc, an essential trace element, contributes to the development and growth of skeletal system. The purpose of the current research was to investigate the effects of Zinc-loaded Carbon Nanotubes/Chitosan composite biomaterials in the restoration of rat skull defects, and to verify the hypothesis that these zinc ions of appropriate concentration would strengthen the osteogenesis of rat defects. Four different groups of composite biomaterials were fabricated from no Zinc Carbon nanotubes/Chitosan (GN), 0.2% Zinc-Carbon nanotubes/Chitosan (GL), 1% Zinc-Carbon nanotubes/Chitosan (GM) and 2% Zinc-Carbon nanotubes/Chitosan (GH). After characterizations, these composite biomaterials were then transplanted into rat skull defects. The experimental animals were executed at 12 weeks after transplanted surgeries, and the rat skull defects were removed for related analyses. The results of characterizations suggested the Zinc-loaded composite biomaterials possessed good mechanical and osteoinductive properties. An important finding was that the optimal osteogenic effect appeared in rat skull defects transplanted with 1% Zinc-Carbon nanotubes/Chitosan. Overall, these composite biomaterials revealed satisfactory osteogenesis, nevertheless, there was a requirement to further perfect the zinc ion concentrations to achieve the better bone regeneration.
Advances in bio-telemetry technology have made it possible to automatically monitor and classify behavioural activities in many animals, including domesticated species such as dairy cows. Automated behavioural classification has the potential to improve health and welfare monitoring processes as part of a Precision Livestock Farming approach. Recent studies have used accelerometers and pedometers to classify behavioural activities in dairy cows, but such approaches often cannot discriminate accurately between biologically important behaviours such as feeding, lying and standing or transition events between lying and standing. In this study we develop a decision-tree algorithm that uses tri-axial accelerometer data from a neck-mounted sensor to both classify biologically important behaviour in dairy cows and to detect transition events between lying and standing.
In addition to mechanical properties, uniform fuel dispersion, efficient removal of water and high electric conductivity are also important functions of a bipolar plate. The capillary effect of micro-featured flow field may attract water from the carbonic diffusion layer and promote more evenly dispersion of fuels into the diffusion layer. Thus, it may improve the performance of proton exchange membrane (PEM) fuel cells. In this research, the Lithography Galvanik Abformung (LIGA) manufacturing processes with electroforming technology are investigated for the production of micro-featured flow field of the metallic bipolar plates. The micro-features are designed in conjunction with the existing flow channel to form an integrated flow field system. Instead of silicon wafer, a 4in. wafer size SS304 stainless steel plate is used as the substrate. The LIGA processes of photo masking, spin coating, exposure and development are employed to create electric conducting die with flow field pattern. Electroforming of this metallic plate coated with flow field patterned photo resist will result in the main flow channel on the SS304 plate. The same processes were conducted for the second iteration to form micro-features. Thus, metallic bipolar plates with micro-features are produced using the electroforming technology. A single cell with total cell area of 16cm2 and reaction area of 4cm2 was produced. It has micro-features of 100 and 200μm width and of 50μm depth. The dimensions of the main flow channel were 300μm in width and 200μm in depth. Single cell tests were conducted to evaluate its performance. The cell performance of the single cell with SS304 metallic bipolar plates exceeds similar size single cell with silicon or glass fiber substrates. The electroforming is a promising technology for metallic bipolar plates with micro-features and micro-fuel cell.
A novel quaternary ammonium salt—1,1-dimethylpyrrolidinium tetrafluoroborate (DMPBF4), tetraethylammonium tetrafluoroborate (TEABF4), and spiro-(1,1′)-bipyrrolidinium tetrafluoroborate (SBPBF4) were prepared and dissolved in acetonitrile (ACN) and propylene carbonate (PC) for electrolyte systems of electric double-layer capacitors (EDLC). Physical properties such as thermal stability, solubility, and ionic conductivity were determined and six different electrolyte systems with 1 M concentration were electrochemically evaluated by linear sweep voltammetry, cyclic voltammetry, galvanostatic charge-discharge, and float test. To investigate the origin of the physical and electrochemical properties at the molecular level, quantum calculations for the chemical species in the electrolytes were also carried out. Compared to the standard electrolytes TEABF4 and SBPBF4, the novel DMPBF4 electrolyte exhibits a higher gravimetric capacitance, superior rate capability, and improved cycling stability. The energy and power density of EDLCs using DMPBF4 in the ACN electrolyte reach 40.61 Wh kg−1 and 8.09 kW kg−1, respectively, at the working voltage of 3.0 V. Moreover, EDLCs with DMPBF4 in ACN (PC) retain 87.9% (87.5%) of their initial capacitance after 1000 h of float testing at 3.0 V. The results indicate that DMPBF4 can be a promising electrolyte salt for EDLC application.