batterydata/paper-abstracts huggingface dataset:
We demonstrate the fabrication of freestanding and flexible MnO-decorated carbon nanofiber (CNF) composites as lithium-ion battery anode materials. They showed an initial capacity of 1131mAh·g−1 and a retention capacity of 923mAh·g−1 after 90 charge-discharge cycles under a current rate of 123mA·g−1. Decoration of MnO nanocrystals on the CNFs enhanced the lithium storage capacity of the composites. The optimal concentration of MnO was identified by varying its weight percentage from 0 to 7%. When the concentration was increased, more reaction sites for lithium ions were formed, which in turn increased the overall specific capacity. The intensity of the D band in the Raman spectra of the decorated CNFs was higher than that of the G band, indicating the enhanced diffusion of lithium ions. The plateau region of the discharge curve observed in the cases of higher MnO concentrations indicated the active reduction of MnO; consequently, a higher reversible capacity was achieved. These flexible and freestanding MnO-CNF nanocomposites can be used in lightweight, portable, and flexible batteries.
Background Electroconvulsive therapy (ECT) remains the most effective acute treatment for severe major depression, but with significant risk of adverse cognitive effects. Unidirectional electrical stimulation with a novel electrode placement and geometry (Focal Electrically Administered Seizure Therapy (FEAST)) has been proposed as a means to initiate seizures in prefrontal cortex prior to secondary generalization. As such, it may have fewer cognitive side effects than traditional ECT. We report on its first human clinical application. Method Seventeen unmedicated depressed adults (5 men; 3 bipolar disorder; age 53 ± 16 years) were recruited after being referred for ECT. Open-label FEAST was administered with a modified spECTrum 5000Q device and a traditional ECT dosing regimen until patients clinically responded. Clinical and cognitive assessments were obtained at baseline, and end of course. Time to orientation recovery, a predictor of long-term amnestic effects, was assessed at each treatment. Nonresponders to FEAST were transitioned to conventional ECT. Results One patient withdrew from the study after a single titration session. After the course of FEAST (median 10 sessions), there was a 46.1 ± 35.5% improvement in Hamilton Rating Scale for Depression (HRSD24) scores compared to baseline (33.1 ± 6.8, 16.8 ± 10.9; P < 0.0001). Eight of 16 patients met response criteria (50% decrease in HRSD24) and 5/16 met remission criteria (HRSD24 ≤ 10). Patients achieved full re-orientation (4 of 5 items) in 5.5 ± 6.4 min (median = 3.6), timed from when their eyes first opened after treatment. Conclusion In this feasibility study, FEAST produced clinically meaningful antidepressant improvement, with relatively short time to reorientation. Our preliminary work first in primates and now depressed adults demonstrates that FEAST is feasible, safe, well-tolerated and, if efficacy can be optimized, has potential to replace traditional ECT.
We show high activity in non-nitrogen doped and non-metal electrocatalysts based on carbon nanotubes with onset potential up to 0.73 V vs. RHE by the formation of hole defects on the walls of carbon nanotubes, followed by annealing under Ar atmosphere. From the power generation test, this catalyst can deliver a maximum output power of 55.68 mW (mg−1CNT cathode). Through temperature programmed desorption (TPD) and electrochemical analysis, the creation of new active sites is correlated with the removal of high temperature CO desorbing functionalities. Residual metal impurities were examined by the use of inductively coupled plasma-mass spectroscopy (ICP-MS), high angle annular dark-field (HAADF) and electron energy loss (EELS) analysis. The extremely low amount of metal impurities and the absence of impurity coordination at the edge planes after electrochemical characterization suggest that it is unlikely that impurities directly contribute to ORR. We conclude by proposing that the origin of ORR activity is a result of carbon restructuring and the possible formation of topological defects during the removal of high temperature CO desorbing functional groups.
In this work, a catalyst based on nanostructured Ru x Mo y Se z compounds was prepared by thermolysis of their carbonyl compounds in organic solvents. Evaluation of the catalytic activity was carried out via cyclic voltammetry on carbon paper. Synthesized catalyst was supported either by carbon black (Vulcan XC-72) or by polyaniline coated carbon black. The oxygen reduction activity and methanol tolerance of both electrodes was compared with commercial E-TEK 20% Pt–C electrode and polyaniline coated commercial E-TEK 20% Pt–C electrode. Characterisation of the catalysts was made using XRD and SEM. An important increase in the oxygen reduction reaction rate was observed using polyaniline coated carbon black matrix.
Hydrogen
        storage in liquid organic heterocycles is feasible thermodynamically and is attractive in terms of simplicity, safety, scalability, heat management and economy, but extensive catalyst development is needed to bring it to fruition.
Pure Ni(OH)2, Al-substituted, Co-substituted, Al and Co co-substituted α-Ni(OH)2 were prepared by homogeneous precipitation from nickel nitrate solution in the presence of urea. The physical properties of the samples with different additives were examined by XRD and SEM. The XRD results show that the Ni(OH)2 samples with different additives prepared by this method are typical α-phases. The SEM results show that the pure Ni(OH)2 and Co-substituted sample display spherical particles with some degree of agglomeration. However, Al-substituted sample and Al and Co co-substituted sample are the aggregates of irregularly shaped particles. The results of galvanostatic charge–discharge experiments show that the addition of Co2+ decreases the discharge potential, but the addition of Al3+ and co-doping of Al3+ and Co2+ increase the discharge potential. The cycle stability of Al and Co co-substituted α-Ni(OH)2 is obviously improved compared with Al-substituted α-Ni(OH)2. The results of diffusion coefficient of proton ( D H + ) experiment show that the D H + values at different depth of discharge (DOD) are increased markedly by the doping of Al3+ or the co-doping of Al3+ and Co2+ and decreased by the doping of Co2+. The electrochemical transfer resistance (R t) value of Co-substituted sample increases at first and then decreases with the increase of DOD. However, R t increases with the increase of DOD for other samples.
Two studies investigate children's knowledge of internal parts and their endorsement of immanent causes for the behaviors of living and non-living things. Study 1, involving 48 preschoolers, showed that domain-specific knowledge of internal parts develops between ages 3 and 4. Study 2 included 43 4-year-olds, 30 8-year-olds, and 35 adults and showed that preschoolers do not endorse these internal parts as causally responsible for familiar biological events (e.g., movement, growth). Like adults and older children, however, preschoolers endorse an abstract cause, “its own energy,” for animals but not for machines. The results suggest that children recognize domain-specific internal parts as early as age 4 but that their causal attributions are not yet anchored in a detailed biological theory. Findings are discussed in terms of theory change and an essentialist assumption.
ABSTRACT A facile and efficient hydrolysis process was proposed to create graphene nanosheets-SnO2 nanocomposites (GSCS). The hydrolysis reaction results in the formation of pure phase SnO2 nanoparticle (∼10nm in size) uniformly dispersed on graphene sheets while simultaneously cause reduction of graphene oxide. The as-prepared materials were characterized in detail by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Raman spectra and X-ray photoelectron spectroscopy (XPS). In the investigation of photocurrent response properties, it was found that the photocurrent of GSCS was 130μA/cm2, which is about 4 times higher than that of SnO2.
The proliferation of Micro-Electro-Mechanical Systems (MEMS), portable electronics and wireless sensing networks has raised the need for a new class of devices with self-powering capabilities. Vibration-based piezoelectric energy harvesters provide a very promising solution, as a result of their capability of converting mechanical energy into electrical energy through the direct piezoelectric effect. However, the identification of fast, accurate methods and rational criteria for the design of piezoelectric energy harvesting devices still poses a challenge. In this work, a level set-based topology optimization approach is proposed to synthesize mechanical energy harvesting devices for self-powered micro systems. The energy harvester design problem is reformulated as a variational problem based on the concept of topology optimization, where the optimal geometry is sought by maximizing the energy conversion efficiency of the device. To ensure computational efficiency, the shape gradient of the energy conversion efficiency is analytically derived using the material time derivative approach and the adjoint variable method. A design velocity field is then constructed using the steepest descent method, which is further integrated into level set methods. The reconciled level set (RLS) method is employed to solve multi-material shape and topology optimization problems, using the Merriman–Bence–Osher (MBO) operator. Designs with both single and multiple materials are presented, which constitute improvements with respect to existing energy harvesting designs.
The diffusion coefficient is a key property of materials. Electrochemical impedance spectroscopy (EIS) is a routine tool to determine the diffusion coefficient. Albeit being versatile for varied electrochemical systems and powerful in distinguishing multiple processes in a wide frequency spectrum, the EIS method usually needs a physical model in data analysis; misuse of models leads researchers to provide unwarranted interpretation of EIS data. Regarding diffusion, the simple and elegant formula developed by Warburg has been serving as the canonical model for more than a century. The classical Warburg model has very strict assumptions, however, it is used in a wide range of scenarios where assumptions may not be satisfied. It is the main purpose of the present article to define the boundary of applicability of the Warburg model and develop alternative models for cases beyond the boundary. In so doing, the Warburg model is revisited and its limitations and assumptions are scrutinized. Afterwards, new impedance models for more complicated and realistic scenarios are developed. The present article features: (1) generalization of the boundary condition when treating diffusion in bounded space and geometrical variants; (2) diffusion impedance in porous electrodes and fractals; (3) the effect of electrostatic interactions and coupling between diffusion and migration on the diffusion impedance in electrolytic solutions; (4) introduction of homotopy perturbation method to treat the convective diffusion; (5) physical interpretations of diffusion impedance behaviors.
The 1996 reauthorization of the Safe Drinking Water Act required that each state in the US addresses the protection of public drinking water sources, including the development and implementation of a source-water assessment program. Such a program includes delineating source-water assessment areas, inventorying potential contaminant sources within this area, and determining the water system's susceptibility to contamination. The public was also involved in various phases of the program. Hawaii’s groundwater source assessment program is presented, along with an approach for implementation, which is consistent with federal requirements. The approach integrates groundwater models, aquifer databases, and a geographic information system. Source assessment areas were delineated by using numerical groundwater-flow models that used site-specific data to their fullest availability. The proposed approach is flexible enough to allow easy future updates as more sources are identified or as new information becomes available. The final product includes numerical scores that quantify the relative source susceptibility to contamination. Aquifer models developed in this study are potentially useful for future site-specific protection efforts or for other modeling purposes.
Olivine LiFePO4/C cathode materials were synthesized by carbothermal reduction method at different temperatures. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), particle size analysis and charge–discharge test. The results showed that both the crystallization degree and particle size increased remarkably with the synthesis temperature increasing. The LiFePO4/C synthesized at 750°C showed a highest initial discharge specific capacity of 145mAhg−1 at 1C rate, which decreased to 60mAhg−1 after 500 cycles. However, the sample prepared at 850°C exhibited a lower initial discharge capacity of 135mAhg−1 at 1C rate, whose capacity could also reach 105mAhg−1 after 500 cycles. The material synthesized at lower sintering temperature had lower crystallization degree and plenty of nano-sized microstructure, leading to its higher electrochemical activity and initial discharge capacity. But at the same time, the lower sintering temperature also leads to the instability of the crystal structure and the solution of active materials, which results in the degradation of discharge capacity on long-time cycling. In short, synthesizing the material with perfect crystallization degree and moderate particle size is an effective way to improve the cycling performance of LiFePO4/C cathode materials.
Advancements in taxometric and dimensional approaches to personality psychopathology have pushed for refinements to the borderline personality disorder (BPD) phenotype, but proposed revisions to the diagnosis in major nosological systems hinge in part on evidence to support their validity. We review recent phenotypic and cognitive research on BPD and consider ways that changes to the phenotype may be validated using cognitive measures.
Benign external hydrocephalus in infants, characterized by macrocephaly and typical neuroimaging findings, is considered as a self-limiting condition and is therefore rarely treated. This review concerns all aspects of this condition: etiology, neuroimaging, symptoms and clinical findings, treatment, and outcome, with emphasis on management. The review is based on a systematic search in the Pubmed and Web of Science databases. The search covered various forms of hydrocephalus, extracerebral fluid, and macrocephaly. Studies reporting small children with idiopathic external hydrocephalus were included, mostly focusing on the studies reporting a long-term outcome. A total of 147 studies are included, the majority however with a limited methodological quality. Several theories regarding pathophysiology and various symptoms, signs, and clinical findings underscore the heterogeneity of the condition. Neuroimaging is important in the differentiation between external hydrocephalus and similar conditions. A transient delay of psychomotor development is commonly seen during childhood. A long-term outcome is scarcely reported, and the results are varying. Although most children with external hydrocephalus seem to do well both initially and in the long term, a substantial number of patients show temporary or permanent psychomotor delay. To verify that this truly is a benign condition, we suggest that future research on external hydrocephalus should focus on the long-term effects of surgical treatment as opposed to conservative management.
Pb(100) and Pb(111) single crystals in 50mM H2SO4 aqueous solution have been investigated by in situ electrochemical atomic force microscopy (EC-AFM) under potential control. We have succeeded in observating high resolution images of Pb(100) and Pb(111) single crystals, as well as high resolution and morphological images of PbSO4 crystals formed on the Pb single crystals. We found that the top face of PbSO4 crystals formed on Pb(100) is PbSO4(001), while that on Pb(111) is PbSO4(100). We also found that the atomic rows along the [100] and [010] direction of PbSO4(001) surface were parallel with those along the [011] and [011&#x0304;] direction of the Pb(100) substrate, while those along the [010] and [001] direction of the PbSO4 (100) surface were parallel with those along the [011&#x0304;] and [1&#x0304;11] direction of the Pb(111) substrate.
Different animal models are used as fracture models in orthopaedic research prior to implant use in humans, although biomechanical forces can differ to a great extend between species due to variable anatomic conditions, particularly with regard to the gait. The rabbit is an often used fracture model, but biomechanical data are very rare. The objective of the present study was to measure axial forces, bending moments, and bending axis directly in the rabbit tibia in vivo. The following hypothesis was tested: Axial forces and bending moments in the mid-diaphysis of rabbit tibia differ from other experimental animals or indirectly calculated data.
Among tea polyphenols, the anti-initiating properties of polymeric black tea polyphenols (PBPs), the most abundant polyphenols in black tea, are poorly elucidated. Hence, this study was undertaken to investigate the effects of PBP extract on the induction of phase II enzymes. PBP extract induced transcriptional up-regulation of phase II enzymes in liver and lungs by increasing Nrf2-mediated antioxidant-responsive element (ARE) binding. PBP extract did not alter Nrf2 or Keap1 at the transcriptional level but may have increased their levels by posttranslational modifications such as phosphorylation and decreased ubiquitination. PKC and PI3-kinase-mediated phosphorylation of Nrf2 seems to be critical for the release of Nrf2 from Keap1 and its subsequent nuclear translocation. mafK was found to be the heterodimeric partner of Nrf2 for binding to ARE sequences in liver upon PBP extract pretreatment. Differences in phosphorylation, activation of cellular kinases, and speculated heterodimeric binding partners of Nrf2 by PBP extract in hepatic and pulmonary tissues suggested the possibility of tissue-specific differences in the activation of Nrf2. Thus, we conclude that the pathway of PBP extract-induced ARE activity involves the activation of Nrf2 through phosphorylation by PKC and PI3-kinases in hepatic cells, which is critical for the increased stability of Nrf2 upon release from Keap1 and nuclear translocation, respectively.
α-Fe2O3 nanorods were synthesized by a facile hydrothermal method. The as-prepared α-Fe2O3 nanorods have a high quality crystalline nanostructure with diameters in the range of 60–80nm and lengths extending from 300 to 500nm. The crystal structure of the α-Fe2O3 nanorods was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The α-Fe2O3 nanorod anodes exhibit a stable specific capacity of 800mAh/g. This indicates significantly improved electrochemical performance in lithium-ion cells, compared to that of commercial microcrystalline α-Fe2O3 powders.
This paper presents a new design concept of transmissions for the hybrid scooters. These transmissions consist of a one-degree-of-freedom planetary gear train and a two-degree-of-freedom planetary gear train to from a split power system and to combine the power of two power sources, a gasoline engine and an electric motor. In order to maximize the performance and reduce emissions, the transmissions can provide a hybrid scooter to run five operating modes: electric motor mode; engine mode; engine/charging mode; power mode, and regenerative braking mode. The main advantages of the transmissions proposed in this paper include the use of only one electric motor/generator, need not use clutch/brake for the shift of the operating modes, and high efficiency. The kinematics, power flow, and mechanical efficiency analyzes are performed; and according to these results, the evaluation of transmission power performances are accomplished.
A new alkoxide-based sol containing lithium isopropoxide, vanadylisopropoxide, di-n-butyl-phosphate, acetic-acid and polyvinylpyrrolidone, was used for the synthesis of monoclinic α-Li3V2(PO4)3/C composites by sol-gel and electrospinning techniques. The precursor mixture was highly soluble in organic solvents and thereby suitable for different synthesis techniques like sol-gel electrospinning or conventional sol-gel synthesis, to generate α-Li3V2(PO4)3/C nanocomposites with zero- and one-dimensionality. Electrospinning resulted in well-defined nanofibers and conventional sol-gel synthesis in polydisperse, isotropic nanoparticles. Phase composition and morphology in the composite nanostructures was examined by XRD, TGA, FT-IR, Raman, SEM and HR-TEM analysis. Comparative constant-current and cyclovoltammetric measurements of α-Li3V2(PO4)3/C composite applied as conventional film electrodes (nanoparticles and nanofibers) and self-supporting nanofiber electrodes revealed the influence of electrode texturing on the electrochemical performances. The nanofibrous self-supported electrodes showed superior cycling stability giving an initial discharge capacity of 124mAhg−1 at 0.2°C with retention of 95% after 50 cycles with rate variation in a voltage range of 3–4.3V.
The search for clean and renewable sources of energy represents one of the most vital challenges facing us today. Solid oxide fuel cells (SOFCs) are among the most promising technologies for a clean and secure energy future due to their high energy efficiency and excellent fuel flexibility (e.g., direct utilization of hydrocarbons or renewable fuels). To make SOFCs economically competitive, however, development of new materials for low-temperature operation is essential. Here we report our results on a computational study to achieve rational design of SOFC cathodes with fast oxygen reduction kinetics and rapid ionic transport. Results suggest that surface catalytic properties are strongly correlated with the bulk transport properties in several material systems with the formula of La0.5Sr0.5BO2.75 (where B=Cr, Mn, Fe, or Co). The predictions seem to agree qualitatively with available experimental results on these materials. This computational screening technique may guide us to search for high-efficiency cathode materials for a new generation of SOFCs.
Ionic liquids have been extensively investigated in recent years either as a main medium or as an additive for various applications. In the present study, we have synthesized four room temperature ionic liquids (RTILs) of the 1-butyl-3-methylimidazole (BMIM) family with different anions, including BF4−, PF6−, SCN−, and C2H6NO3S− (taurinate, denoted as Tau), and investigated their effect as additives on the electrochemical dissolution and deposition of Ni in the conventional Watts solution. Our electrochemical studies revealed that the addition of BMIM[SCN] significantly lowered the electrode potential for Ni dissolution compared to the rest of the RTILs as well as the Watts solution. The Ni anodes after the electrochemical dissolution and the Ti cathodes after the electrochemical deposition were further characterized using cyclic voltammetry to assess their electrochemical active surface areas (EASAs). It was found that the sample anodically dissolved in the Watts solution containing BMIM[SCN] had the highest EASA and that the nickel deposited on the Ti substrate in the Watts solution with BMIM[Tau] additive exhibited the highest EASA compared with the Ni deposition in all the other tested solutions. Our study has also shown that the addition of RTILs may affect the electrochemical nickel dissolution and deposition processes adversely or beneficially depending on the compositions of the RTILs.