batterydata/paper-abstracts huggingface dataset:
There is growing interest in flexible, cost-effective, and binder-free energy storage devices to meet the special needs of modern electronic systems. Herein we report a general, scalable, eco-friendly, and cost-effective approach for the fabrication of nano-Fe3O4-anchored three-dimensional (3D) carbon nanofiber (CNFs) aerogels (Fe3O4@BC-CNFs). The preparation processes include the anchoring of Fe2O3 nanoparticles on bacterial cellulose (BC) nanofibers with intrinsic 3D network structure and subsequent carbonization at different temperatures. The aerogel carbonized at 600 °C (Fe3O4@BC-CNFs-600) is highly flexible and was directly used as working electrodes in lithium-ion batteries without metal current collectors, conducting additives, or binders. The Fe3O4@BC-CNFs-600 demonstrates greatly improved electrochemical performance in comparison to the bare Fe3O4 nanoparticles. In addition to its excellent flexibility, a stable capacity of 755 mAh g−1 for up to 80 cycles is also higher than most of carbon-Fe3O4 hybrids. The high reversible capacity and excellent rate capability are attributed to its 3D porous network structure with well-dispersed Fe3O4 nanoparticles on the surfaces of CNFs.
Wheat straw is one of the major lignocellulosic plant residues in many countries including China. An attractive alternative is the utilization of wheat straw for bioethanol production. This article mainly studies a simple one-step wet milling with Penicillium simplicissimum and weak acid to hydrolysis of wheat straw. The optimal condition for hydrolysis was ball milling 48 h in citrate solvent (pH = 4) with P. simplicissimum H5 at the speed of 500 rpm and the yield of sugar increased with increased milling time. Corresponding structure transformations before and after milling analyzed by X-ray diffraction, transmission Fourier transform infrared spectroscopy, and environmental scanning electron microscopy clearly indicated that this combined treatment could be attributed to the crystalline and chemical structure changes of cellulose in wheat straw during ball milling. This combined treatment of ball milling, mild acid, and fungus hydrolysis enabled the conversion of the wheat straw. Compared with traditional method of ball milling, this work showed a more simple, novel, and environmentally friendly way in mechanochemical treatment of wheat straw.
Flow batteries show promise for very large-scale stationary energy storage such as needed for the grid and renewable energy implementation. In recent years, researchers and developers of redox flow batteries (RFBs) have found that electrode and flow field designs of PEM fuel cell (PEMFC) technology can increase the power density and consequently push down the cost of flow battery stacks. In this paper we present a macroscopic model of a typical PEMFC-like RFB electrode-flow field design. The model is a layered system comprised of a single passage of a serpentine flow channel and a parallel underlying porous electrode (or porous layer). The effects of the inlet volumetric flow rate, permeability of the porous layer, thickness of the porous layer and thickness of the flow channel on the flow penetration into the porous layer are investigated. The maximum current density corresponding to stoichiometry is estimated to be 377 mA cm−2 and 724 mA cm−2, which compares favorably with experiments of ∼400 mA cm−2 and ∼750 mA cm−2, for a single layer and three layers of the carbon fiber paper, respectively.
The research suggests that there is a penalty for invoking one’s sixth amendment right in a trial. This study uses Tobit models to empirically document the existence of a trial penalty, and we provide estimates of the magnitude of its effect. In a comparative analysis of three alternative trial settings, we find that courts treat defendants differently under alternative sets of rules. Thus, we provide some evidence that defendants might face discrimination in court. We find that the lengths of the sentences of those found guilty in jury trials are 11 years longer than those found guilty in bench trials or those taking plea bargains. Further, we find that women are more likely to be found guilty in bench trials than in jury trials and that prior convictions are directly related to jury convictions and unrelated to bench trials. In addition, gang affiliation is less likely to matter for bench trials.
Globally, heavy metal pollution is a major issue which has seriously threatened the sustainability of environment. The toxic heavy metals emerging from sources like, industries, tannery, sewage wastes and other metal discharging industries have been found to adversely affect the density, diversity and physiological activities of soil microbiota (Xie et al. 2016). Among various heavy metals, cadmium, a highly lethal metal is widely used in batteries, for coating, electroplating, PVC stabilizers and as a component in alloy formation in various industries (Sharma et al. 2015). Due to lack of regulatory policy for controlled and safe discharge, cadmium is added to the environment via many anthropogenic activities like combustion of metal ores, burning of wastes and by the use of fossil fuels. However, after it accumulates in soils, Cd can be absorbed by plants leading eventually to the disruption of food chain and indirectly affects human health (Rahimzadeh et al. 2017). Chromium is yet another toxic metal which is used in plating, alloy formation, tanning of animal hides, for inhibiting water corrosion, textile dyes and mordants, pigments, ceramics, refractory bricks, pressure-treated lumber etc. The overuse and abuse of Cr has however hugely dented human health by acting as carcinogenic and mutagenic element (Oliveira 2012). Nickel which is even though present in very low concentrations in the environment has been found to cause serious human health problems when present beyond threshold concentrations. For instance, Ni can cause- (i) genotoxicity (ii) several types of carcinomas (iii) toxic impacts on the immune system and (iv) damage to other metabolically active tissues (Das et al. 2018).
Scandium doped LiScxMn2-xO4 compounds are synthesized by solid-state method, which show single phase with rod-like polyhedron morphology. The Sc-doping decreases the lattice parameter ‘a’ marginally due to the change in the inter-atomic distance of the metal oxide bonds as confirm by Rietveld refinement. In addition, the expansion of LiO4 tetrahedron and contraction of MnO6 octahedron by ∼0.01 Å upon doping are observed. The Sc2p3/2 peak at 402.5 eV and Sc2p1/2 peak at 407.2 eV in the XPS spectrum of LiSc0.06Mn1.94O4 confirms the presence of Sc in the spinel structure. The symmetric stretching of MnO bond of LiSc0.06Mn1.94O4 shifts lower value (∼4 cm−1) than that of LiMn2O4 indicating the occupancy of Sc3+ ion in the octahedral site. The diffusion coefficient value of LiSc0.06Mn1.94O4 (1 × 10−12cm2s−1) is one-order higher than that of undoped LiMn2O4 (1 × 10−13 cm2s−1). LiMn2O4 delivers a discharge capacity of 117 mAhg−1 at 1C with a capacity retention of 74% after 500 cycles, whereas under similar condition LiSc0.06Mn1.94O4 delivers a discharge capacity of 114 mAhg−1 with a capacity retention of >90%. LiSc0.06Mn1.94O4 also delivers excellent rate capability due to high diffusion coefficient and less charge transfer resistance compared to the parent compound. The structure and morphology of the Sc-doped electrode after 500 cycles remains intact without any formation of Mn-rich agglomeration suggest that the reduction of Mn2+ ion dissolution as well as Jahn-Teller distortion. Hence LiSc0.06Mn1.94O4 can be a potential cathode material for lithium ion batteries.
This study examined whether children with mathematical difficulties (MDs) or comorbid mathematical and reading difficulties have a working memory deficit and whether the hypothesized working memory deficit includes the whole working memory system or only specific components. In the study, 31 10-year-olds with MDs and 37 10-year-olds with both mathematical and reading difficulties were compared with 47 age-matched and 50 younger controls (9-year-olds) on a number of working memory tasks. Compared with the age-matched controls, both groups of children with MDs performed worse on tasks tapping the central executive (e.g., visual matrix span) and the phonological loop (e.g., word span). More important, the MD group performed worse than the younger controls on the counting span task, whereas the group with comorbid mathematical and reading difficulties performed worse on the counting span task and the visual matrix span task. These findings provide support for the assumption that children with MDs have a working memory deficit. More specifically, children with MDs have a central executive deficit connected to concurrent processing and storage of numerical and visual information.
The influence of paste density and curing temperature on soaking and formation was investigated by different analytical methods including X-ray, porosimetry, BET and SEM. The soaking was carried out in sulfuric acid with different gravity and the time was varied between 0.5 and 24 h. Plates cured at high temperature resulting in mainly tetrabasic lead sulfate (4BS) behave markedly different to those cured at low temperature having only tribasic lead sulfate (3BS). The behaviour of plates cured at medium temperature resulting in a mix of both 4BS and 3BS was between the two extremes. There was also some influence of the paste density but smaller than the effect of different curing conditions. The results can be explained by considering the different mass structure and pore size distribution of the respective plate version.
A silicon monoxide (SiO)-carbon composite prepared by ball-milling and pyrolysis is evaluated as an anode material for lithium-ion batteries. Electrochemical tests demonstrated that the first charge and discharge capacities of the material are about 1050 and 800mAhg−1, respectively, with a first-cycle efficiency of 76%. The disproportionation reaction of pure SiO into Si and SiO2 during pyrolysis is confirmed by means of XRD and 29Si MAS NMR. The cycle performance of this material shows an excellent reversible capacity retention of 710mAhg−1 over 100 cycles without any potential or capacity restrictions. This improved cycle performance is attributed to the stable microstructure, enhanced electrical contact afforded by the pyrolyzed carbon, and the amorphous phase transformation of the active material during cycling.
Amongst anode materials for lithium ion batteries, silicon's high theoretical capacity, environmental friendliness, low potential vs Li/Li+, material abundance and technological maturity, turn it to a strong candidate for the replacement of carbon-based anodes. In this work we studied the influence of various electrolyte solutions and additives to the silicon's stability over cycling. We have to use electrolyte solutions and additives that form a stable Solid Electrolyte Interphase (SEI) layer, which protects silicon's integrity and prolongs its cycle life. In this work, we present the experimental results of half and full cells with silicon anodes with various electrolytes and additives. It becomes obvious that the electrolyte solution plays an immense role to the formation of SEI layer and thus, the electrochemical properties of silicon anodes.
Kesterite thin-film solar cells feature abundant non-toxic elements. Here, Antunez et al. present a process to simultaneously optimize the conversion efficiency and voltage over a wide range of light intensities appropriate for small-scale, distributed and indoor applications.
Understanding how events throughout the annual cycle interact to influence individual fitness and hence population dynamics is crucial to optimize conservation strategies for migratory birds. Despite major advancements in technology, direct tracking devices for passerine songbirds are still limited by the need for recapturing tagged individuals. Stable-isotope analysis of bird tissue has the opportunity to supply information on a larger number of individuals, although it is limited by the indirect knowledge of the geographical position of the birds. In this study, we provide a first attempt to combine annual spatio-temporal data achieved from direct tracking with information on local environmental conditions by using stable isotopes (δ13C and δ15N). We use this approach to investigate if environmental conditions at the wintering area in southern Africa influence timing of spring migration and carry-over to affect breeding performance in a long-distance migratory passerine bird, the Red-backed Shrike (Lanius collurio). We found that individuals wintering in relatively moist conditions (depleted in δ13C) and at lower latitudes (closer to the breeding grounds) departed later on spring migration than individuals in more xeric habitats. However, the effect of non-breeding area conditions and latitude were not found at subsequent migration stages and late departing individuals spent fewer days on migration towards the breeding grounds. Although conditions in the non-breeding range have previously been suggested to influence population fluctuations in Red-backed Shrikes, we found no evidence of a carry-over effect on breeding performance. This study highlights the potential of combining different approaches when investigating seasonal interactions in migratory animals.
Typhoons inflict large damage to societies, but are usually difficult to monitor in close proximity in real-time without expensive instruments. Here we study the possibility of using seismic waveforms on the seafloor and on land to monitor the turning of a far away or approaching typhoon. Up to 67% of the typhoons making landfall in Taiwan come from the eastern shore, so that we deployed broadband ocean-bottom seismometers (OBSs) offshore eastern Taiwan in 2006 to study ground motion in close proximity to a typhoon. Typhoons generate ocean waves, which generate pressure signals in the water column before being transmitted to the seafloor as seismic waves and recorded by the OBSs. The ground motions on the seafloor correlate with locally increased (ocean) wave heights and wave periods, suggesting that the ground motions are mostly induced by in situ or nearby pressure fields, as shown by coherence function analyses. When a typhoon turns and changes wave-wave interaction near the source region, a new set of en echelon patterns develops which can be observed by OBSs and land stations. Similar features occur when a typhoon crosses a landmass and re-enters the ocean. The energy level ratio between the single-frequency and double-frequency microseisms also changes abruptly when the typhoon turns. These features can potentially help near real-time early warning with little cost to complement other conventional typhoon early warning methods.
Practice-based research is not uncommon in healthcare. In fact, the way nurses and doctors train is through extensive and intensive practice [1]. In other words, practice-based research has been used to gain new knowledge partly by means of practice and the outcomes of that practice [2]. Practice based research networks have also been gaining on importance in healthcare as ways of addressing research questions informed by practicing clinicians. They aim to gather data and improve existing practices of primary care [3], practice-based research is not only about gaining new knowledge via practice and improving existing practices.
Ion channels are targets of various antiepileptic drugs. In cerebral presynaptic nerve endings Na+ and Ca2+ channels are particularly abundant, as they control neurotransmitter release, including the release of glutamate (Glu), the most concentrated excitatory amino acid neurotransmitter in the brain. Several pre-synaptic channels are implicated in the mechanism of action of the pro-convulsive agent, 4-aminopyridine (4-AP). In the present study the effects of levetiracetam and other established and newer (vinpocetine) anti-epileptic drugs, as well as of the anti-depressant, sertraline on the increase in Ca2+ induced by 4-AP in hippocampal isolated nerve endings were investigated. Also the effects of some of the anti-seizure drugs on the selective increase in Ca2+ induced by high K+, or on the selective increase in Na+ induced by veratridine were tested. Sertraline and vinpocetine effectively inhibited the rise in Ca2+ induced by 4-AP, which was dependent on the out-in Na+ gradient and tetrodotoxin sensitive. Carbamazepine, phenytoin, lamotrigine and oxcarbazepine inhibited the rise in Ca2+ induced by 4-AP too, but at higher concentrations than sertraline and vinpocetine, whereas levetiracetam, valproic acid and topiramate did not. The three latter antiepileptic drugs also failed in modifying other responses mediated by the activation of brain presynaptic Na+ or Ca2+ channels, including Glu release. This indicates that levetiracetam, valproic acid and topiramate mechanisms of action are unrelated with a decrease in presynaptic Na+ or Ca2+ channels permeability. It is concluded that depolarized cerebral isolated nerve endings represent a useful tool to unmask potential antiepileptic drugs targeting presynaptic Na+ and/or Ca2+ channels in the brain; such as vinpocetine or the anti-depressant sertraline, which high effectiveness to control seizures in the animal in vivo has been demonstrated.
Research examining the relationships between performance measures of emotional intelligence (EI), coping styles, and academic achievement is sparse. Two studies were designed to redress this imbalance. In each of these studies, both EI and coping styles were significantly related to academic achievement. In Study 1, 159 community college students completed the Mayer–Salovey–Caruso Emotional Intelligence Test (MSCEIT) and problem-focused, emotion-focused, and avoidant coping scales. Collectively, the coping variables significantly mediated the relationship between EI and grade point average (GPA) for Emotion Perception, Emotion Facilitation of Thought and Emotion Management (but not for Emotional Understanding). Problem-focused coping was the only single significant mediator, mediating the relationship between emotion management and GPA (but not other branches and GPA). In Study 2, 293 middle school students completed the Situational Test of Emotion Management for Youths (STEM-Y) and scales measuring the same three coping strategies. In this study, the coping variables again significantly mediated the relationship between emotion management and GPA. Once again, problem-focused coping was a significant mediator. Collectively, these results suggest that better educational outcomes might be achieved by targeting skills relating to emotion management and problem-focused coping.
Transmission electron microscopy (TEM) of rapidly frozen biological specimens, or cryo-EM, would benefit from the development of a phase plate for in-focus phase contrast imaging. Several types of phase plates have been investigated, but rapid electrostatic charging of all such devices has hindered these efforts. Here, we demonstrate electron phase manipulation with a high-intensity continuous-wave laser beam, and use it as a phase plate for TEM. We demonstrate the laser phase plate by imaging an amorphous carbon film. The laser phase plate provides a stable and tunable phase shift without electrostatic charging or unwanted electron scattering. These results suggest the possibility for dose-efficient imaging of unstained biological macromolecules and cells.
Understanding of the impact of antipsychotic medications on cognition requires differentiating between treatment effects and practice effects. This prospective study examines expectations for change on neuropsychological assessments and possible differential practice effects in community dwelling schizophrenia patients (n =27) who are clinically stable and on a stable medication regimen when compared to demographically similar psychiatrically healthy controls (n =29). All participants were administered the MATRICS Consensus Cognitive Battery (MCCB) twice over a period of four weeks. The use of Regression Based Norms for Change (RBNC) and Reliable Change Index (RCI) was completed to anchor estimates of meaningful change to a demographically similar control group. A repeated measures ANOVA was used to examine the effects of time and diagnosis on MCCB composite scores. A repeated measures MANOVA was used to examine the effects of time and diagnosis, and their interaction for MCCB subtests. Estimates of meaningful change are provided. A significant main effect was observed for time; no significant interactions were observed. There was no support for differential practice effects. In the absence of any behavioral, cognitive, or pharmaceutical interventions, these findings suggest limited change in performance over time in either group.
Rechargeable aqueous zinc-ion batteries (ZIBs) are feasible for grid-scale applications due to their unique attributes such as safe, sustainable, and low-cost. However, it is limited by cathode materials, which requires a stable host structure and fast channel for zinc ions diffusion. Here, we develop various kinds of potassium vanadates (K2V8O21, K0.25V2O5, K2V6O16·1.57H2O and KV3O8) as cathodes for aqueous ZIBs. K2V8O21 and K0.25V2O5 with tunnel structure can maintain a stable structure and are conducive to the faster zinc ion diffusion during repeated cycles compared to the layered KV3O8 and K2V6O16·1.57H2O that suffer from structural collapse. The optimal K2V8O21 cathode exhibits excellent zinc storage performance, with a high capacity of 247 mA h g−1 at 0.3 A g−1 and a good rate at 6 A g−1 as well as excellent cyclic stability up to 300 cycles. The results suggest K2V8O21 is a very promising cathode for aqueous ZIBs, which could be extended to construct other high-performance cathode materials with a similar crystal structure (e.g. β-Na0.33V2O5, Li0.3V2O5, Ag0.33V2O5, etc.) for zinc storage.
Hybrid microwave synthesis has been applied for preparation of Li4Ti5O12, Li2Ti3O7, Li2TiO3 and LiTiO2 for the first time. Stepwise heating was used for avoiding the instantaneous release of gas by-product and obtaining well-shaped samples. The samples were characterized by powder X-ray diffraction, energy-dispersive X-ray analysis and scanning electron microscopy. The obtained samples have relatively uniform particle sizes. The electrochemical performance of Li4Ti5O12 and Li2Ti3O7 were investigated. The first discharge capacity of Li4Ti5O12 was 150mAhg−1 and 141mAhg−1 after 27 cycles and a very flat discharge and charge curve of Li4Ti5O12 was shown at about 1.56V. Similarly, Li2Ti3O7 exhibits good cycle performance. The initial discharge capacity is 118mAhg−1 and 30th cycle is still 112mAhg−1.
To validate physical activity estimates by the Sensewear Pro3 activity monitor compared with indirect calorimetry during simulated free living in patients diagnosed with osteoarthritis of the hip pre or post total hip arthroplasty.
The corrosion behaviors of perovskite La0.8Sr0.2Co0.3Fe0.7O3−δ (LSCF) in the sodium tetrasulfide melt have been studied to demonstrate its possibility to be used as a coating material for the positive current collector in the sodium sulfur battery (Na/S). The electrochemical techniques including potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) are applied in the study. The results demonstrate that the corrosion process of the LSCF in sodium tetrasulfide melt is activation controlled. The corrosion current density of the LSCF is approximate 10 times smaller than that of the 316L stainless steel. Two compact corrosion layers which may act as a stable barrier retarding the corrosion process have formed on the surface of LSCF after immersed for 130 days. The promising results suggest that LSCF exhibits high corrosion resistance against molten sodium tetrasulfide and may be an appropriate candidate coating material for the positive current collector in Na/S battery.