batterydata/paper-abstracts huggingface dataset:
Mesoporous separator membranes based on poly(vinylidene fluoride-co-trifluoroethylene), PVDF-TrFE, were prepared through the removal of ZnO nanoparticles from the polymer matrix composite. Different filler concentrations were used, and the evaluation of the morphology, mechanical properties, uptake and ionic conductivity of the membranes were demonstrated that they depend on initial ZnO content in the composite. On the other hand, the vibration peaks characteristics of PVDF-TrFE and the thermal properties are independent on initial filler content. The membrane with the best ionic conductivity, 1.6 mS/cm, is the one prepared after 70 wt.% ZnO removal. The separator membranes were assembled in Li/C-LiFePO4 half-cells exhibiting good rate capability and cycling performance, the best battery performance being obtained for the PVDF-TrFE after 70 wt.% ZnO removal. The good performance of the developed separators was also demonstrated in full battery cells. Thus, a way to tailor membrane mesoporosity is presented and it is shown that the obtained membranes represent suitable separators for lithium-ion battery applications.
Abstract Conduction of electrons without resistance. This phenomenon was discovered by Onnes in 1911 accidentally. In fact, he was testing for the temperature of liquid helium gas. He tested a number of times to make sure the resistance of Hg indeed went to zero. This observation did not agree with the Ohm's law, which stood as the law of electrical conduction for years among physicist. Following Onne's discovery, there was a huge effort made among physicist to find whether other elements may or may not have the same property. These efforts, while admirable, did not lead to a co-relatable result that may help us understand the phenomenon. However, it was established that the electrons that carried superconducting currents were based on electron pair. From 1911 to 1952, a few proposals were made to explain the phenomenon, but none was accepted. It was around 1954 the BCS theory (Badeen, Cooper, Shereefer), which was based on the Cooper pairing theory, was accepted as the theory of Superconductivity and the Nobel prize was awarded in 1957. The problem was that theory predicted did not stand up to the test of time, in particular the arrival of high-temperature superconductors (some are above 120K), while the prediction of the BCS theory is no higher than 32K. The largest problem is that no other theory can be accepted or even considered to be printed in a respected Journal of Physics!
Primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system is an aggressive malignancy that exhibits unique biological features and characteristic clinical behaviour, with overall long-term survival rates of around 20–40 %. Clinical outcome has improved following the advent of chemoradiation protocols incorporating high-dose methotrexate in the mid-1980s, but disease relapse and adverse neurocognitive sequelae remain major clinical challenges. To address this, investigators have focused on improving drug therapy with novel cytotoxic combinations, monoclonal antibody therapy, and intensive chemotherapy consolidation approaches, in an attempt to improve disease control whilst reducing the requirement for whole-brain radiotherapy. Outcomes for patients that are older, immunocompromised, or have relapsed/refractory disease remain unsatisfactory and there is a paucity of clinical trial data to guide treatment of these groups. This review highlights recent advances in pathobiology, imaging, and clinical management of PCNSL and looks ahead to research priorities for this rare and challenging lymphoid malignancy.
This study aimed to assess cognitive function and associated factors among school age children in Goba Town, South-Eastern Ethiopia. School based cross-sectional study was employed on 131 school children age 8–11 years. Cognitive function was assessed by Kaufman Assessment Battery for Children (KABC-II) and Ravens colored progressive matrices (Raven’s CPM) test. Descriptive statistics, independent t test, one way ANOVA and logistic regression were used in statistical analysis. The mean (±SD) score of Raven’s CPM test and triangles test was 22.02(±4.79) and 15.17 (±3.24) respectively. The mean (±SD) for short term memory measures such as word order, hand movement number recall was 15.66 (±3.03), 9.09 (±2.88) and 8.91 (±2.19) respectively. The mean score (±SD) of pattern score was 9.63 (±4.43). There was a statistically significant mean difference in hand movements and pattern score between those children who currently used iodized salt and non iodized salt(p<0.05). Wealth index was associated with rovers score (P=0.044). Breakfast consumption was statistically associated with triangles (P<0.001). Those children who had eaten breakfast less than seven days in last week had above 3 times higher odd to score RPM below average(AOR=3.05; 95% CI: 1.07–8.68). This might implicates that promotion of iodized salt intake, improving dietary diversity, improving breakfast eating habit, and improving wealth index are important modifiable factors of cognitive function.
A novel material of Sn/TiO2 nanowire array (TNA) composite has been designed and fabricated to be used as anode material for lithium-ion batteries. Firstly, highly ordered, vertically oriented rutile TiO2 nanowire array is synthesized directly on titanium substrate by solvothermal procedure without any template. Subsequently, tin metal is chemically deposited into the interspace of the film, forming a TNA/Sn composite. By calcinations in atmosphere, the skin-deep Sn is oxidized to SnO2, and further turns to Li2O in Li-ion insertion process. The field-emission scanning electron microscopy (FE-SEM) and transmission electron microscope (TEM) images indicate that the dimensions of TiO2 nanowires and Sn particles are 10±2nm and 8±1nm wide, respectively. The energy-dispersive X-ray spectroscopy (EDX) result reveals that the weight ratio of tin to TiO2 is 0.22. The first charge capacity reaches as high as 1610mAhcm−3, and the capacity retention is 62.3% after 300 cycles.
Tin dioxide/carbon composites is an important class of promising candidates for anode materials with superior electrochemical performance and thus have attracted extensive attention. Herein, a tube-in-tube nanostructure, denoted as CNT@void@SnO2@C, has been fabricated by a facile and novel strategy. The possible formation mechanism is also discussed and determined by TEM, XRD and XPS characterizations. As a promising anode material for lithium-ion batteries, the CNT@void@SnO2@C exhibits superior lithium storage properties, delivering a reversible capacity of 702.5 mAh g−1 at 200 mA g−1 even after 350 cycles. The excellent performances should be benefited from the peculiar tube-in-tube nanostructure, in which SnO2 located between CNT and outermost carbon coating layers can sure the structural integrity and high conductivity during long-term cycling, and one-dimensional void space formed between the inner CNT and outer SnO2@C nanotubes, in particular, can provide larger free space for alleviating the huge volume variation of SnO2 and accommodating the stress formed during repeated discharge/charge process.
Avoidance behavior can be a useful parameter for assessing the ability of organisms to escape from pollutants in their environment. For soil evaluation, a variety of invertebrates is used including the oribatid mite Oppia nitens. Here, we tested the avoidance behavior of O. nitens using a two-chamber test and an escape test with exposures to different cadmium concentrations of up to 800 mg kg−1 dry LUFA 2.2 soil for 2, 4, and 6 days, and up to 7 weeks. With the two-chamber method, the oribatid mites had the choice between clean and polluted soils, whereas they were allowed to escape from a box with polluted soil to clean containers without soil with the escape method. Avoidance of cadmium was observed after 2 days in both tests and the net response of the mites in the two-chamber test increased with increasing cadmium exposure concentrations. Mite responses varied through time, especially with the escape method; with the avoidance behavior becoming more variable and overall non-significant with longer test durations. This is the first study investigating the escape test simultaneously with long-term avoidance of cadmium by O. nitens. This mite species is a promising species for avoidance testing in soil ecotoxicology, but more experiments are needed to evaluate the factors that influence its responses in laboratory tests and the consequences for its distribution in contaminated ecosystems.
In this communication, we use first-principles based multi-level computational methods to predict the crystal structure of Li4C6O6, the key intermediate material that can be oxidized to Li2C6O6 or reduced to Li6C6O6. This predicted structure leads to an X-ray diffraction (XRD) pattern in good agreement with experiment, validating the predicted structure. With this structure in hand one can proceed to determine details for the electrochemical properties of these organic electrodes (chemical potential for Li ion as a function of loading and the mechanism for the lithiation/delithiation process) useful in designing optimum systems.
LiFePO4/C composites were successfully prepared by a solid-state reaction in order to compare conventional heat treatment and microwave-assisted synthesis at different times of sintering. Microwave-assisted synthesis is interesting due to the fact that energy and inert gas consumption can be greatly reduced with respect to the conventional treatment, resulting in a cheaper synthesis method. The relationship between particle morphology and crystal structure using the composite synthesis was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) with refinements of the crystal structures carried out by the Rietveld method. In addition, the electrochemical performances were evaluated using constant current charge/discharge tests, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). It was observed that the samples prepared by microwave heating had a better electrochemical behavior than those prepared in a conventional furnace. Also, in general, a higher sintering time improved the electrochemical behavior, but with increased particle sizes, and consequently, a decreased specific capacity.
During the past decades, the potential derived from the hybridization of inorganic materials, has been widely studied and presented. The capability of tuning materials’ performances, not only in terms of tailoring their physico-chemical properties to answer prerequisites of a given application, but also regarding the elaboration of novel concepts, opened a door to a radical new world in materials science. However, as a consequence of their diverse chemistry, structure, envisaged applications and historical background, each subgroup of inorganic lamellar compounds were usually discussed separately. This review intends to reflect upon the different categories of lamellar compounds and their hybridization strategies, regardless of their chemical and historical differences. The hybridization strategies of lamellar compounds are divided and presented under two main categories. Firstly, the intercalation/exfoliation approach, where the hybridization of lamellar compounds is operated in pre-formed inorganic layered materials. Secondly, the in situ synthesis methods, where the hybrid character of the layered compound is imparted simultaneously along with the layered inorganic compounds synthesis routes. Finally, in order to tackle the important question of “the place and role of hybrid lamellar compounds in consumer end-products, an integration challenge”, the proven concepts and potential applications defined for these organic-inorganic compounds are discussed.
The paper proposes a bi-level optimisation framework for Electric Vehicle (EV) fleet charging based on a realistic EV fleet model including a transport demand sub-model. The EV fleet is described by an aggregate battery model, which is parameterised by using recorded driving cycle data of a delivery vehicle fleet. The EV fleet model is used within the inner level of the bi-level optimisation framework, where the aggregate charging power is optimised by using the dynamic programming (DP) algorithm. At the superimposed optimisation level, the final State-of-Charge (SoC) values of individual EVs being disconnected from the grid are optimised by using a multi-objective genetic algorithm-based optimisation. In each iteration of the bi-level optimisation algorithm, it is generally needed to recalculate the transport demand sub-model for the new set of final SoC values. In order to simplify this process, the transport demand is modelled by using a computationally efficient response surface method, which is based on naturalistic synthetic driving cycles and agent-based simulations of the EV model. When compared to the single-level charging optimisation approach, which assumes the final SoC values to be equal to 1 (full batteries on departure), the bi-level optimisation provides a degree of optimisation freedom more for more accurate techno-economic analyses of the integrated transport-energy system. The two approaches are compared through a simulation study of the particular delivery vehicle fleet transport-energy system.
As the stabilization criteria for landfill sites, only chemical criteria for the leachate discharges from the landfill sites have been used in Japan and many other countries. Recently, chemical oxidation has been developed as a method for the early-stabilization of landfills. However, by-products that are difficult to detect by chemical analysis can be produced by this method. Therefore, toxicity tests are useful tools for detecting the changes of leachate quality after application of this method. The heat source in the A landfill was analyzed by organic position inquiry technology, and ozone-treated leachate was sprayed back to the heat source in the landfill. Toxicity changes of the leachate after the spray were monitored using Microtox™, ToxScreen-II, and DaphTox tests. The hardly-degradable organic matter was efficiently removed and toxicities of the leachate in the heat source decreased after the application. These toxicity results were significantly related to chemical oxygen demand (COD) changes. Thus, it was concluded that the toxicity tests were effective for monitoring the leachate quality after applying the chemical oxidation method for landfill stabilization, and its incorporation to establish the criteria for early-stabilization of landfill sites needs to be considered.
The Meža River Valley has been a center of mining, ore processing and iron- and steel-based metallurgical industry for more than 300 a. This paper deals with stream sediments draining this area. Loads of potentially toxic metals and metal-bearing phases were investigated 10 a after the cessation of Pb and Zn mining. Sediments in the upper Meža River Valley show significant pollution with Pb and Zn as a consequence of mining and ore processing. The highest contents of Pb and Zn were found in the Meža tributaries, which directly drain mine waste deposits (maximum values: 19,300mg/kg Pb and 37,900mg/kg Zn). These results reflect transport of contaminated material from mine waste sites and indicate that the inactive mine and its mine wastes are sources of metal contamination in the surrounding environment. Contents of Cr, Ni, Cu and Co are increased in the lower Meža River Valley, in the area of Ravne, as a result of the iron and steel industry. The contribution of the Meža River to the metal-load in the Drava River is evident. Metal-bearing phases, identified in stream sediments by SEM/EDS, are assigned to three areas, according to their source and genesis. The Mežica mining district source area is characterized by ore minerals of geogenic/technogenic origin (cerussite, sphalerite, smithsonite and galena), the Ravne source area is characterized by technogenic trace metal-bearing Fe-alloys, Fe-oxides and spherical trace metal-oxides and the Meža and Drava River catchment areas are represented by geogenic metal-bearing accessory and common rock-forming minerals, such as zircon, ilmenite, rutile, sphene, barite and monazite. SEM/EDS analyses of stream sediments agree well with the results of chemical analyses and they prove to be a very useful tool for identification of metal-bearing phases and their characterization according to source and genesis.
Electrochemical cycling behavior of LiFePO4 (LFP) cathode charged with different upper voltage limits has been studied. Reversible capacity of the cathode is not significantly increased by pushing up the charge voltage limit. However, charge voltage limit plays a role affecting the passivation film of the electrode. When cycled with low charge voltage limit, the passivation film is not well developed and the LFP electrode exhibits high surface impedance. When charged to extremely high voltage limit, oxidation of electrolyte produces carbon-based layer coating the LFP particles. The optimized charge voltage limits of 3.9 and 4.3V are obtained under different experimental conditions. Long term cycling behavior of full cell is evaluated against MCMB anode. After 1000 electrochemical cycles, around 60% of the initial capacity is lost. Lithium inventory loss is found to be the main factor responsible for the cell failure. The impact of charge voltage limit on the cycling performance of LFP cathode is buried in the Li consumption during electrochemical cycles. Fe precipitation and the resultant impedance rise on the anode side, which are widely accepted to be responsible for the capacity decay of graphite/LFP full cells, is not observed in this study.
Li[Li1/6Ni1/4Mn7/12]O2−x F x (x =0, 0.025, 0.05, 0.075, 0.1) as the cathode materials for rechargeable lithium batteries have been synthesized via the co-precipitation method followed by a high-temperature solid-state reaction. Field emission scanning electron microscopy images exhibit that fluorine substitution catalyzes the growth of the primary particles. Although the initial discharge capacity decreases as the fluorine content increasing, the fluorine substituted materials present significant improvement in the cycling performance. Among the synthesized materials, Li[Li1/6Ni1/4Mn7/12]O1.95F0.05 exhibits excellent high temperature (50°C) cycling performance with a capacity retention of 93.7% after 30 cycles while the bare Li[Li1/6Ni1/4Mn7/12]O2 cathode exhibited only 73.7%.
Prussian blue analogue (KMFe-PBA), K x MFe(CN)6·nH2O, was investigated as a new cathode material to insert/extract Ca2+ reversibly using a Ca-based organic electrolyte. A dehydrated KNiFe-PBA (i.e. K x NiFe(CN)6) electrode with a high electro-conductive additive demonstrated reversible capacities of ∼50mAh/g with Coulombic efficiencies of ∼92% even though the decomposed capacity of the electrolyte was indicated at the discharge. During the 1st discharge and discharge-charge, a detailed structural characterization was performed using an ex-situ X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). XRD patterns and XPS spectra on the discharged and discharged-charged cathodes indicate that Ca2+ is inserted and extracted into and from the interstitial sites of KNiFe-PBA without destruction of the open framework structure.
Despite the impact of chronic pain on the quality of life in patients, including changes to affective state and daily life activities, rodent preclinical models rarely address this aspect of chronic pain. To better understand the behavioral consequences of the tissue and nerve injuries typically used to model neuropathic and inflammatory pain in mice, we measured home cage and affective state behaviors in animals with spared nerve injury, chronic constriction injury (CCI), or intraplantar complete Freund’s adjuvant. Mechanical hypersensitivity is prominent in each of these conditions and persists for many weeks. Home cage behavior was continuously monitored for 16days in a system that measures locomotion, feeding, and drinking, and allows for precise analysis of circadian patterns. When monitored after injury, animals with spared nerve injury and complete Freund’s adjuvant behaved no differently from controls in any aspect of daily life. Animals with CCI were initially less active, but the difference between CCI and controls disappeared by 2weeks after injury. Further, in all pain models, there was no change in any measure of affective state. We conclude that in these standard models of persistent pain, despite the development of prolonged hypersensitivity, the mice do not have significantly altered “quality of life.” As alteration in daily life activities is the feature that is so disrupted in patients with chronic pain, our results suggest that the models used here do not fully reflect the human conditions and point to a need for development of a murine chronic pain model in which lifestyle changes are manifest. Mice with spared nerve injury, chronic constriction injury, and complete Freund’s adjuvant injection did not alter behavior in their home cage or a battery of affective tests.
We report here on comparative measurements of cationic transference numbers of some lithium battery related electrolytes including lithium tetrafluoroborate in propylene carbonate, lithium hexafluorophosphate in blends of ethylene carbonate/diethyl carbonate and ethylene carbonate/propylene carbonate/dimethyl carbonate, as well as lithium difluoromono (oxalate) borate in an ethylene carbonate/diethyl carbonate blend via four different methods. Whereas three electrochemical methods yield transference numbers decreasing with concentration in accordance with electrostatic theories, valid for low to intermediate concentrations of the electrolyte, nuclear magnetic resonance spectroscopy measurements show increasing transference numbers with increasing concentration. The discrepancy is attributed to effects of ion–ion and ion–solvent interaction.
Vanadium redox flow battery (VRFB) is one of the most promising large-scale energy storage system; however, a widespread VRFB development is still limited by the poor electrochemical activity of graphite electrodes and a poor understanding of redox reactions occurring at electrode/electrolyte interface. In this work, DFT was performed to study the first solvation shell structure of all vanadium ions and to investigate the reactivity of modified graphite electrodes toward the V2+/V3+ redox species. The results suggest that the presence of oxygen and nitrogen functionalities at the electrode edges provides more active sites for adsorption of the V2+/V3+ redox couple, and therefore improve electron transfer kinetics. These results have been experimentally validated by means of Cyclic Voltammetry and Electrochemical Impedance Spectroscopy with carbon black electrode having different density of oxygen and nitrogen-containing surface groups.