batterydata/paper-abstracts huggingface dataset:
A rational solvothermal method is proposed to achieve the conversion from a Zn contented metal organic framework to ZnO mesoporous single-crystal-like spheres. The as-prepared ZnO sphere is composed of oriented assembled primary crystals, which exhibits single crystal nature with narrow pore size distribution and high surface area. In addition, time depending trails indicate the metal organic framework functions as reservoir to control the release of Zn species and the organic molecules also serve as directing regent to facilitate the oriented assembling of the ZnO primary units. Thanks to this structure coherence, the ZnO sphere delivers high electron mobility, which enables reduced carrier recombination and improved collection efficiency of the photoelectrons when used as photoanode in CdS/CdSe sensitized solar cell. The device achieves a high power conversion efficiency of ∼6.20%, which is substantially improved from that of regular ZnO nanoparticles (∼5.02%). Moreover, when evaluated as anode for lithium ion battery, the ZnO sphere based electrode demonstrates high reversible capacity of 1016.7 mA h g−1 at 100 mA g−1 after 100 cycles, and excellent high rate stability which shows impressive reversible capacity of 698.4 mA h g−1 at 1000 mA g−1 after 300 cycles.
Photovoltaic systems (PVSs) and plug-in electric vehicles (PEVs) are becoming increasingly common and expected to be further integrated into electric power distribution systems (EDSs) in the near future. In this paper, the combined effects of PVSs and PEVs on the feeder and transformer loads, voltage profiles and harmonic distortions of an urban area EDS are investigated. The results indicate that the simultaneous connection of PVSs and PEVs, at the correct ratio, can impact load reduction and produce a reduction in voltage variations while potentially resulting in an increase the total harmonic distortion of voltage (THDV). In addition, this paper presents changes in the characteristic daily load and voltage profiles and changes in the THDV of the system caused by the simultaneous operation of PVSs and PEVs. The test EDS with 19 nodes is based on a real EDS. Two seasons, summer and winter, and several different degrees of penetration of PVSs and PEVs were studied. We used a stochastic approach to model the loads, PVSs and PEVs based on data measured in real systems and data found in the literature.
The accuracy of the exposure assessment is a critical factor in epidemiological investigations of pesticide exposures and health in agricultural populations. However, few studies have been conducted to evaluate questionnaire-based exposure metrics. The Agricultural Health Study (AHS) is a prospective cohort study of pesticide applicators who provided detailed questionnaire information on their use of specific pesticides. A field study was conducted for a subset of the applicators enrolled in the AHS to assess a pesticide exposure algorithm through comparison of algorithm intensity scores with measured exposures. Pre- and post-application urinary biomarker measurements were made for 2,4-D (n=69) and chlorpyrifos (n=17) applicators. Dermal patch, hand wipe, and personal air samples were also collected. Intensity scores were calculated using information from technician observations and an interviewer-administered questionnaire. Correlations between observer and questionnaire intensity scores were high (Spearman's r=0.92 and 0.84 for 2,4-D and chlorpyrifos, respectively). Intensity scores from questionnaires for individual applications were significantly correlated with post-application urinary concentrations for both 2,4-D (r=0.42, P<0.001) and chlorpyrifos (r=0.53, P=0.035) applicators. Significant correlations were also found between intensity scores and estimated hand loading, estimated body loading, and air concentrations for 2,4-D applicators (r-values 0.28–0.50, P-values<0.025). Correlations between intensity scores and dermal and air measures were generally lower for chlorpyrifos applicators using granular products. A linear regression model indicated that the algorithm factors for individual applications explained 24% of the variability in post-application urinary 2,4-D concentration, which increased to 60% when the pre-application urine concentration was included. The results of the measurements support the use of the algorithm for estimating questionnaire-based exposure intensities in the AHS for liquid pesticide products. Refinement of the algorithm may be possible using the results from this and other measurement studies.
Bear bile has long been used in the Asian traditional pharmacopoeia. Bear farming first started in China ~30 years ago in terms of reducing the number of poached bears and ensuring the supply of bear bile. Approximately 13,000 bears are today captivated on Asia’s bear farms: their teeth are broken and the claws are also pulled out for the sake of human safety; the bears are imprisoned in squeeze cages for years; and a catheter is daily inserted into a bear’s gall bladder or a tube is implanted inside its body in order to collect the dripped bile—captive bears moan in severe pain whenever the bile is extracted. When the bears cannot produce sufficient bile, they are often left to die of starvation. It must be impossible to justify the bile extraction from living bears because (1) medicinal/herbal alternatives are similar to bear bile; (2) there is no evidence to suggest that bear farming has any beneficial effects on wild bear populations; and (3) ethical problems lie not only in the painful bile extraction but also the whole lifecycle of captive bears. In conclusion, human welfare (health care) based on traditional medicine is upheld by sacrificing bear welfare. Since a trial calculation suggests that it is economically unfeasible to keep a proper balance between bear welfare and the traditional pharmacopeia, the cultivation of herbal alternatives seems to be a possible solution to phase out bear faming and maintain the practice of traditional medicine in Asia.
While combating social exclusion has been a key target of the European Union’s social policy in recent years, the concept remains contested and various ways of measuring its prevalence have been proposed. In the Netherlands a survey-based method has been in use since 2004, which refers to four theoretical elements of social exclusion: material deprivation, limited social participation, inadequate access to basic social rights and a lack of normative integration. In this article we propose an improved and more concise version of the instrument. Using focus groups and cognitive tests, the study first examined whether it adequately covers the different elements of social exclusion. Based on the results, the existing items were reformulated and supplemented. A revised questionnaire was then submitted to a new stratified sample of 650 respondents, randomly drawn from an online panel and a database of people without access to the Internet. The weighted outcomes may be regarded as representative for the entire adult Dutch population, although some caveats apply. Using nonlinear canonical correlation analysis, we identified a single underlying dimension in our new data set. This contains 15 items, with three to four indicators for each of the theoretical elements of social exclusion. According to our general index, just under 5 % of the Dutch population aged 18 years or older are faced with a serious degree of social exclusion. On the four subscales the figure ranges from 7 % (social rights) to 22 % (material deprivation).
The aim of this study was to assess heavy metals mobility and toxicity in sediments collected from a dam reservoir in the conditions of intensive human impact by using chemical fractionation and a battery of bioassays. In the studies, the test organisms were exposed to substances dissolved in water (Microtox, Phytotestkit) as well to substances absorbed on the surface of solid particles (Phytotoxkit, Ostracodtoxkit F). The studies showed that sediments from the Rybnik reservoir are toxic, but the tested organisms showed different sensitivity to heavy metals occurring in the bottom sediments. The sediment samples were classified as toxic and very toxic. Moreover, the studies showed a higher toxicity in solid phases and whole sediment than in pore water. The lowest sensitivity was observed in H. incongruens (solid phases) and V. fischeri (pore water, whole sediment). The studies revealed that the toxicity of the sediments is caused mainly by heavy metal forms associated with the solid phase of the sediments. The studies did not confirm the metals occurring in fraction I (exchangeable) to be bioavailable and toxic to living organisms because most correlations between the metal concentration in fraction I and the response of the organisms were negative. The highest mobility from the bottom sediments was found in zinc, average mobility—in copper, cadmium and nickel, and low mobility—in chromium and lead. Organic matter is likely to be the most important factor controlling metal distribution and mobility in the studied sediments.
Computer simulations are compared with experimental data for Bellcore PLION® cells using the graphite/1 M LiPF6 in EC:DMC (2:1)/LiMn2O4 system. The motivation is to model lithium-ion polymer cells having higher active material loadings and competitive energy densities and specific energies to liquid lithium-ion batteries. Cells with different electrode thickness, initial salt concentrations, and higher active material loadings were examined using the mathematical model to understand better the transport processes in the plasticized polymer electrolyte system. A better description of the ionic conductivity is employed based on new conductivity data. Improvements in the agreement between the simulations and experimental data are obtained by using the contact resistance at the current collector/electrode interface as an adjustable parameter for different cells, whose values vary from 20 to 35 Ω cm2 (based on separator area). The contact resistance is believed to originate at the mesh current collector interfaces. Reducing the salt diffusion coefficient by a factor of two or more at the higher discharge rates was necessary to obtain better agreement with the experimental data. Based on the experimental data and model predictions from this study, it can be concluded that the solution-phase diffusion limitations are the major limiting factor during high-rate discharges.
This study focuses on the stability of dyslexia status from Grade 2 to Grade 8 in four groups: (a) no dyslexia in either grade (no-dyslexia, n = 127); (b) no dyslexia in Grade 2 but dyslexia in Grade 8 (late-emerging, n = 18); (c) dyslexia in Grade 2 but not in Grade 8 (resolving, n = 15); and (d) dyslexia in both grades (persistent-dyslexia, n = 22). We examined group differences from age 3.5 to age 14 in (a) reading, vocabulary, phonology, letter knowledge, rapid naming, IQ, verbal memory; (b) familial and environmental risk and supportive factors; and (c) parental skills in reading, phonology, rapid naming, verbal memory, and vocabulary. Our findings showed group differences both in reading and cognitive skills of children as well as their parents. Parental education, book-reading frequency, and children’s IQ, however, did not differentiate the groups. The children in the persistent-dyslexia group exhibited widespread language and cognitive deficits across development. Those in the resolving group had problems in language and cognitive skills only prior to school entry. In the late-emerging group, children showed clearly compromised rapid naming. Additionally, their parents had the most severe difficulties in rapid naming, a finding that suggests strong genetic liability. The findings show instability in the diagnosis of dyslexia. The members of the late-emerging group did not have a distinct early cognitive profile, so late-emerging dyslexia appears difficult to predict. Indeed, these children are at risk of not being identified and not receiving required support. This study suggests the need for continued monitoring of children’s progress in literacy after the early school years.
Crystalline silicon (c-Si) solar cells featuring a high-temperature processed homojunction have dominated the photovoltaic industry for decades, with a global market share of around 93%. Integrating commercially available crystalline silicon solar cells with high-efficiency perovskite solar cells is a viable pathway to increase the power conversion efficiency, and hence achieve low levelized electricity costs for the photovoltaic systems. However, the fabrication process for this type of cell is challenging due to the many, and often conflicting, material processing requirements and limitations. Here, we present an innovative design for a monolithic perovskite/silicon tandem solar cell, featuring a mesoscopic perovskite top subcell and a high-temperature tolerant homojunction c-Si bottom subcell. The improved temperature tolerance of the c-Si bottom cell permits significantly increased flexibility in the design and fabrication of the perovskite cell. We demonstrate an efficiency of 22.5% (steady-state) and a Voc of 1.75 V on a 1 cm2 cell. The method developed in this work opens up new possibilities in designing, fabricating and commercialising low-cost high-efficiency perovskite/c-Si tandem solar cells.
In this work two three-branched cyanopyridine based monomers were synthesized and used as starting materials for the preparation of viologen derivatives with branched structures. The film synthesis was performed using reductive electropolymerization in aqueous solution. Both electrochemical and spectroelectrochemical characterization proved that the viologen films undergo a well-defined and reversible two step redox reaction, which is the typical performance for viologen materials. Furthermore, FTIR and SEM were utilized to characterize their structures and morphologies. SEM studies showed that the viologen films have a highly porous structure. Additionally, discharging experiments confirmed that the viologen films show different intercalation behavior as size of electrolyte anion had various effects on the redox potential. Finally, it has been proven that these two viologen derivative materials have the potential to be utilized as a supporting material with intrinsic redox activity and with excellent properties for hosting especially negatively charged particles, molecules and macromolecules. The promising properties of these materials make them good candidates in electronics and also in organic solar cells when loaded with large molecules such as fullerenes. In the organic rechargeable battery applications they can be used as anode-active materials as they exhibit high charging-discharging capacity at negative potentials.
Increasing renewable energy generation influences the reliability of electric power grids. Thus, there is a demand for new technical units providing ancillary services. Non-dispatchable renewable energy sources can be balanced by energy storage devices. By large-scale battery energy storage systems (BESSs) grid efficiency and reliability as well as power quality can be increased. A further characteristic of BESSs is the ability to respond rapidly and precisely to frequency deviations, making them technical ideal candidates for primary control provision (PCP). In this paper environmental impacts of PCP by novel Li-ion BESSs are compared to impacts of PCP by state-of-the-art coal power plants (CPPs) using a Life Cycle Assessment (LCA) approach and considering German control market conditions. The coal power plant stock is characterized by varying properties. Thus, different scenarios of CPP operation are analyzed by varying sensitive parameters like efficiency loss and required must-run capacity. Finally, PCP by BESSs and CPPs are compared in terms of environmental performance. The more must-run electricity generation is attributable to PCP of CPPs, the higher are the environmental impacts of these CPPs. This leads to a better relative environmental performance of BESSs in most scenarios. Contrary, comparative or even better environmental performance of CPPs compared to state-of-the-art BESSs can solely be achieved if power plants without load restrictions for provision of primary control and with extreme low efficiency losses caused by PCP are applied. Consequently, the results of this paper indicate that BESSs are a promising option to reduce environmental impacts of primary control provision.
The current study is a pilot test of a screening instrument aimed at flagging children at-risk for dyscalculia. The screening test is designed so that it can be applied by any teacher with minimal instruction and financial investment and it is based on Number Sense battery, NUCALC battery and, first of all, romanian mathematical curriculum. Out of the 45 students from Bucharest (8-11 years) participating in this study, ten scored under the cut-off point of 10, three of which scored under 5. All these children, deemed at risk for dyscalculia, scored above the threshold for mental delay on two IQ tests.
In this article, we report an active-matrix type SnSnSb alloy, which is sandwiched between nitrogen doped reduced graphene oxide (N-rGO) sheets in the form of a nanocomposite, as a high rate capability anode for lithium-ion batteries. The alloy nanocomposite is synthesized via a cheap and industrially scalable route of microwave-assisted hydrothermal synthesis, and is coated onto electrodeposited 3D microporous nickel foam current collector. The additional mechanical buffering, along with effective electron conduction and lithium ion diffusion pathways provided by N-rGO nanosheets and nickel foam, result in a specific capacity of ∼300 mAhg−1 at a specific current of 4 A g-1 by preventing both pulverization and delamination of the active material. This combination of properties in N-rGO decorated SnSnSb nanocomposite anode (with 40 wt% N-rGO) on nickel foam results in a 2nd cycle discharge specific capacity of 705 mAhg−1, with a stable reversible specific capacity of 500 mAhg−1 after 200 cycles @ 0.1 A g-1. The nanocomposite anode also shows capacity retention of 400 mAhg−1 @ 0.8 A g-1 (1C rate) for 120 cycles. As compared to low N-rGO (10 wt%) decorated nanocomposite, the high N-rGO (40 wt%) nanocomposite shows improved performance with a nominal sacrifice of capacity which is at par, if not superior, to the existing commercial graphitic anodes.
In this paper, a novel hybrid maximum power point tracking (MPPT) method is proposed and investigated. The proposed MPPT technique combines the simplicity of perturb and observe (P&O) method and the fast tracking ability of open circuit voltage (OCV) method. The advantages of the proposed MPPT approach include fast tracking speed, no additional circuit required and no temporary power loss. To validate the feasibility of the proposed MPPT technique, an 1.2 kW thermoelectric generation system for industrial waste heat recovery is also constructed, experimental results show that comparing with conventional P&O technique, the proposed method can improve the tracking speed for 42.9% and 86.2% when temperature differences are ΔT = 60 °C and ΔT = 180 °C, respectively. Moreover, the energy loss can be improved by 24.0% and 87.0% when temperature differences are ΔT = 60 °C and ΔT = 180 °C, respectively.
The effect of silver metavanadate doping on physicochemical properties and thermal behaviour of the activated carbons obtained from waste materials was investigated. The carbonaceous supports were subjected to carbonisation at 400 or 600°C. The samples carbonised at 600°C have much more developed surface area and porous structure than the analogous samples obtained at 400°C. Impregnation of activated carbons with silver metavanadate leads to a decrease in their surface area and pore volume. According to thermal analysis (TG, DTG) in the samples containing 1 and 3wt.% of silver metavanadate, AgVO3 is fully decomposed to do vanadium oxide and Ag, with no intermediate products, while in the samples containing 5wt.% AgVO3, this salt is decomposed to vanadyl species as intermediate compounds at 350°C before the formation of V2O5 at 500°C. Moreover, in all samples impregnated with silver metavanadate the nanoparticles of silver undergo crystallisation leading to reduction of Ag+ ions from the vanadium salt to Ag0.
The aim of this study was to evaluate the effect of solidification cooling rates on the as-cast microstructural morphologies of a Pb–1wt%Sn alloy, and to correlate the resulting microstructure with the corresponding electrochemical corrosion resistance in a 0.5M H2SO4 solution at 25°C. Cylindrical low-carbon steel and insulating molds were employed permitting the two extremes of a significant range of solidification cooling rates to be experimentally examined. Electrochemical impedance spectroscopy (EIS) diagrams, potentiodynamic polarization curves and an equivalent circuit analysis were used to evaluate the electrochemical corrosion response of Pb–1wt%Sn alloy samples. It was found that lower cooling rates are associated with coarse cellular arrays which result in better corrosion resistance than fine cells which are related to high cooling rates. The experimental results have shown that that the pre-programming of microstructure cell size of Pb–Sn alloys can be used as an alternative way to produce as-cast components of lead-acid batteries with higher corrosion resistance.
The cathode material is synthesized from FeC2O4·2H2O and LiH2PO4 by a solid-state reaction using citric acid as a carbon source. The electric conductivity of the synthesized LiFePO4 has been raised by eight orders of magnitude from 10−9 Scm−1. The LiFePO4/C composite shows a greatly enhanced rate performance and the cyclic stability at room temperature. It delivers an initial discharge capacity of 128mAhg−1 at 4C, which is retained as high as 92% after 1000 cycles. In addition, the tested low temperature character is attractive. At −20°C, the composite exhibits a discharge capacity of 110mAhg−1 at 0.1C. The homogenous morphology, the porous surface, the small particles inside and the conductive carbon observed contribute much to obtain the favorable electrochemical performance.
To improve the cycling performance and rate capability of the promising layered lithium-rich cathode materials, we substitute Co3+ in Li[Li0.20Mn0.534Ni0.133 Co0.133]O2 with unusually large Y3+ during coprecipitation and synthesize Li[Li0.20Mn0.534 Ni0.133Co0.133-x Yx]O2 (0 ≤ x ≤ 0.0665). The influences of yttrium content on the electrochemical properties of the lithium-rich materials are investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), galvanostatic charge–discharge tests and electrochemical impedance spectroscopy (EIS) techniques. The charge–discharge cycling tests suggest that after heating at 1223K in air for 10h, the material with x =0.00665 deliver a high discharge capacity of 349.7 mAhg−1 after 1 cycle and 225.2 mAhg−1 after 80 cycles with a current rate of 0.1 C between 2.0 and 4.6V vs. Li/Li+. Electrochemical impedance spectroscopy indicates that Li[Li0.20Mn0.534Ni0.133Co0.133-xYx]O2 electrode has lower impedance during cycling. The higher capacity retention and high-rate capability of yttrium-substituted materials can be ascribed to the expanded Li+ diffusing channels in the layered structure, lower surface film resistance and lower charge transfer resistance of the electrode during cycling.