batterydata/paper-abstracts huggingface dataset:
In this study, a prediction model based on artificial neural network is constructed for surface temperature simulation of nickel–metal hydride battery. The model is developed from a back-propagation network which is trained by Levenberg–Marquardt algorithm. Under each ambient temperature of 10°C, 20°C, 30°C and 40°C, an 8Ah cylindrical Ni–MH battery is charged in the rate of 1C, 3C and 5C to its SOC of 110% in order to provide data for the model training. Linear regression method is adopted to check the quality of the model training, as well as mean square error and absolute error. It is shown that the constructed model is of excellent training quality for the guarantee of prediction accuracy. The surface temperature of battery during charging is predicted under various ambient temperatures of 50°C, 60°C, 70°C by the model. The results are validated in good agreement with experimental data. The value of battery surface temperature is calculated to exceed 90°C under the ambient temperature of 60°C if it is overcharged in 5C, which might cause battery safety issues.
Fabricating high-capacity electrode materials with long cycle life is essential to developing high-power energy storage and conversion systems. SiOx is a very attractive anode material for lithium-ion batteries, but both low electronic conductivity and volume effect severely hamper its practical application. In this work, multiwall carbon nanotube (MWCNT) and N-doped carbon are combined to improve the electrochemical properties of SiOx. The synthesized composite (labeled as SiOx/MWCNT/N-doped C) has a network structure, in which MWCNT serves as a highly conductive and porous scaffold facilitating electron and ion transport, while N-doped C improves electric contact between SiOx/MWCNT particles and prevents the physical and electrochemical agglomeration of SiOx. The electrochemical measurement shows that the SiOx/MWCNT/N-doped C exhibits excellent cyclic stability and rate capability. At a current density of 100mAg−1, a stable discharge capacity of about 620mAhg−1 is achieved and the capacity can be preserved up to 450 cycles. The enhanced conductivity and stable electrode structure should be responsible for the excellent electrochemical performance.
A two-dimensional conducting oxide nanosheet, which was prepared by a two-step process involving exfoliation and heat treatment, was employed as a Li–O2 cathode without adding any conductive additives. The 2D nanostructures in the Li–O2 cathode can provide a large surface-to-mass ratio, increase the electrode–electrolyte contact area and facilitate oxygen diffusion and electron transmission. The as-synthesized conducting oxide nanosheet of RuO2 enables the Li–O2 cathode to be operated under full discharge–charge conditions, and to deliver a high specific capacity of ∼900 mA h g−1 with stable discharge–charge overpotentials (0.15/0.59 V) over 50 cycles.
Using a battery of look-ahead-bias free measures of accruals quality (AQ), we find a strong and long-lasting negative relation between future returns and AQ. In decile portfolios that rank on AQ, a hedge portfolio that goes long in the lowest decile and short in the highest decile generates an annualized, risk-adjusted return of 4–12 % over 1-month to 5-year horizons, depending on the AQ measure and the portfolio weighting scheme. The return premiums associated with AQ are, (1) robust to a wide range of AQ measures, (2) robust to a battery of return-informative variables, and (3) not driven by low-priced or small stocks, earnings shocks, or the fourth-quarter effect. The documented premiums are consistent with the information uncertainty effect where firm uncertainty is negatively related to future returns
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Tbx2, a member of the T-box family of genes that encode developmentally important transcription factors, plays a critical role in development and has been linked to cancer. Here a 5′-flanking region of the human Tbx2 gene was cloned and characterized. While we identify a Sp1 element and a reverse CCAAT box to be essential for basal Tbx2 promoter activity, a physical interaction between Sp1 and NF-Y does not seem to be required for mediating their effect. Furthermore, our data reveal a downstream promoter element (DPE) in the Tbx2 promoter which significantly influences basal activity.
Rechargeable aqueous batteries are very attractive as a promising alternative energy storage system, although their reversible capacity is typically limited. A new rechargeable Na-Zn hybrid aqueous battery with nickel hexacyanoferrate (NiHCF) cathode and the nanostructured zinc anode is fabricated. The rational combination of two materials with mild aqueous electrolyte renders the devices with an average operating voltage close to 1.5 V, higher specific capacity of 76.2 mAh g−1, and a good cycling stability with 81% capacity retention for 1000 cycles. These remarkable features can provide guidance for the development of rechargeable batteries from the naturally abundant electrode materials with neutral aqueous electrolytes.
Neurochemicals such as dopamine (DA) and serotonin (S-HT) are linked to disorders such as Parkinson’s disease, epilepsy, addiction and many others. Detection of and monitoring these neurochemicals in vivo and in vitro has become important in treating various disorders. The electroactive nature of DA and S-HT has enabled employing electrochemical techniques to detect them at low concentrations, and a variety of electrodes and approaches have been reported. The use of nanomaterials such as carbon nanotubes, graphene and nanowires has been advocated in recent years for the sensitive detection of neurochemicals. This article reviews the advances in nano biosensors for this application and discusses the future outlook and challenges.
Ca-doped lithium titanates with the formula of Li4−x CaxTi5O12 (x =0, 0.05, 0.1, 0.15, 0.2) were synthesized as anode materials by a simple solid-state reaction in an air atmosphere. The phase structure, morphologies and electrochemical properties of the prepared powders were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and cyclic voltammetry (CV), respectively. XRD revealed that the Ca-doping caused no change on the phase structure and highly crystalline Li4−x Ca x Ti5O12 (0≤ x ≤0.2) powders without any impurity were obtained. SEM images showed that all samples had similar particulate morphologies and the particle size distribution was in the range of 1–2μm. It was observed that Ca-doped lithium titanates employed as the anode materials of lithium-ion batteries delivered excellent electrochemical performances, and sample Li3.9Ca0.1Ti5O12 exhibited a higher specific capacity, better cycling performance and rate capability than other samples. The Li3.9Ca0.1Ti5O12 material showed discharge capacities of 162.4mAhg−1, 148.8mAhg−1 and 138.7mAhg−1 after 100 cycles at 1C, 5C and 10C charge–discharge rates, respectively. Electrochemical impedance spectroscopy (EIS) revealed that the Li3.9Ca0.1Ti5O12 electrode exhibited the highest electronic conductivity and fastest lithium-ion diffusivity, which indicated that this novel Li3.9Ca0.1Ti5O12 material was promising as a high-rate anode material for the lithium-ion batteries.
Corncob is an agro-industrial waste available in large quantities in several countries, including Brazil, which deserves to be better and/or properly used. This work evaluates the use of corncob as a source of cellulose to obtain nanocrystals by acid hydrolysis in order to obtain a material suitable to be a reinforcement agent in the manufacture of nanocomposites. The hydrolysis was performed at 45°C for 30, 60 and 90min, using 15mL of H2SO4 (9.17M) for each gram of cellulose. The resulting cellulose nanocrystals of corncob (CNC) were characterized by crystallinity index, morphology and thermal stability, and their reinforcing capability was evaluated using polyvinyl alcohol (PVA) as the polymeric matrix. Among the hydrolysis conditions carried out, the extraction time of 60min resulted in nanoparticles (CNC60) with larger reinforcing capability. The CNC60 endowed the CNC/PVA composites with a significantly improved tensile strength of 140.2% when only 9% (wt.%) CNC60 was incorporated. The CNC60 presented a needle-shaped nature, high crystallinity (83.7%), good thermal stability (around 185°C), an average length (L) of 210.8±44.2nm and a diameter (D) of 4.15±1.08nm, giving an aspect ratio (L/D) of around 53.4±15.8. The results show that the more suitable filler was CNC60. Since CNC60 has the highest crystallinity among the CNC samples, but does not have the highest aspect ratio, these results suggest that the difference in the crystallinity index has a greater influence on the tensile properties than the aspects ratio, in this case. Cellulose nanocrystals obtained from corncob have great potential as reinforcing agents for the manufacture of nanocomposites.
Psychosis, manifested through formed visual hallucinations or minor hallucinations, is a common non-motor symptom of Parkinson’s disease (PD). The pathogenesis of psychosis in PD remains unclear; however, is possibly linked to structural and functional alterations in the hippocampus. To explore the role of hippocampus in psychosis, a detailed hippocampal subfield analysis was performed on PD patients with (PD-P) and without psychosis (PD-NP), and healthy controls (HC). An automated subfield parcellation was performed on T1 MRI images of 141 subjects (PD-P:42, PD-NP:51, and HC:48). The volumes of 12 subfields on each side were estimated and analyzed between the three groups and were corrected for multiple comparisons using false discovery rates. The volumes were also correlated to psychosis severity and specific neuropsychological tests and finally were employed to predict the psychosis severity in PD-P using a support vector regression (SVR) model. Compared to controls, PD-NP group did not demonstrate any significant differences; however, the PD-P group had significantly lower total hippocampal volume. Bilateral molecular layer, granule cell-dentate gyrus, left subiculum, and hippocampal tail and right CA3, CA4, and HATA illustrated significantly lower volumes, while bilateral hippocampal fissure demonstrated a significant widening. Compared to PD-NP, the PD-P group had higher volume of the bilateral hippocampal fissures. Finally, SVR could significantly predict the psychosis severity from all the subfield volumes. Our findings indicate a higher degeneration of specific hippocampal subfields in PD-P compared to controls and a trend of higher volume of hippocampal fissures in PD-P group than in PD-NP.
This paper proposes a strategy to stabilize the garnet/Li interface by introducing Li3PO4 as an additive in garnet-type Li6.5La3Zr1.5Ta0.5O12. The Li3PO4-added Li6.5La3Zr1.5Ta0.5O12 electrolyte exhibits a room-temperature Li-ion conductivity of 1.4 × 10−4 S cm−1, which is less than that of the Li3PO4-free counterparts (4.6 × 10−4 S cm−1). However, the presence of Li3PO4 improves the interfacial compatibility and suppresses Li-dendrite formation during Li-metal plating/stripping. The symmetric Li/garnet/Li cells with Li3PO4-added Li6.5La3Zr1.5Ta0.5O12 have been successfully cycled at a current density of 0.1 mA cm−2 at 60 °C for 60 h; on contrast, the control cells with Li3PO4-free Li6.5La3Zr1.5Ta0.5O12 display noisy potential with large voltage polarization and get short-circuited completely after 33-h cycling under the same operating condition. The outstanding interface stability can be attributed to the in situ reaction of the Li flux with Li3PO4 to form a self-limiting and ion-conducting interphase, Li3P, which is confirmed experimentally.
Li-rich layered oxides show high reversible capacities (≥250mAh/g) in rechargeable lithium-ion batteries. However, their energy densities are considerably reduced upon cycling due to a voltage depression originated from the layered-to-spinel phase transition. In this study, the influence of site-specific Ga-doping on the electrochemical properties of Li-rich layered oxide is investigated. A powder of Li-rich layered oxide is treated in acid, and then annealed with a Ga source at low temperature (300°C) to insert Ga ions into the powder. Transmission electron microscopy and extended X-ray absorption fine structure analyses indicate that the Ga ions are predominantly doped into the tetrahedral sites of Li2MnO3-like nano-domains in Li-rich layered oxide. Cyclability tests with 18650 full cells clearly reveal that the voltage depression is suppressed by the treatment. Ex-situ X-ray diffraction and first principles calculation results imply that the formation of tetrahedral GaO4 unit in the Li2MnO3-like domain improves the structural stability of Li-rich layered oxide upon cycling.
Mixed metal or transition metal oxides hold an unveiled potential as one of the most promising energy storage material because of their excellent stability, reliable conductivity, and convenient use. In this work, CuMnO2 nanoparticles are successfully prepared by a facile hydrothermal process with the help of dispersing agent cetyltrimethylammonium bromide (CTAB). CuMnO2 nanoparticles possess a uniform quadrilateral shape, small size (approximately 25 × 25 nm–35 × 35 nm), excellent dispersity, and large specific surface specific (56.9 m2 g−1) with an interparticle mesoporous structure. All these characteristics can bring benefit for their application in supercapacitor. A quasi-solid-state symmetric supercapacitor device is assembled by using CuMnO2 nanoparticles as both positive electrode and negative electrode. The device exhibits good supercapacitive performance with a high specific capacitance (272 F g−1), a maximum power density of 7.56 kW kg−1 and a superior cycling stability of 18,000 continuous cycles, indicating an excellent potential to be used in energy storage device.
Bismuth electrodes are particularly interesting owing to their high hydrogen evolution overpotential and electrocatalytic activity. In this work, a novel porous bismuth electrode was prepared via an electrochemical deposition of bismuth on a porous graphite felt of high specific surface area, employing bismuth(III) oxide as reactant and a flow electrochemical cell as reactor. A solubility up to 1molL−1 of bismuth was obtained in basic medium using a suitable complexing agent. We solved the problems linked to the heterogeneous potential distribution in the 3D porous structure and to the formation of dendritic excrescences that led to mechanically fragile material by using a suitable flow electrochemical cell, a periodically changing current with short on-pulses and long off-pulses and by limiting the electrodeposition of Bi on the external surfaces of the felt due to diffusion. A Bi-modified electrode with high specific surface area and low bulk density was achieved using this method.
Civic facilities are part and parcel of standard city planning. To reduce congestion on the surface and to use surface land for other purposes, civic facilities such as sewerage treatment plants, libraries, and shopping malls are being planned and constructed underground. Apart from the various uses of underground space described in earlier chapters, this chapter covers underground civic facilities such as sewage treatment plants, heating systems, swimming pools, education centers or libraries, shopping malls, and sports centers. Keywords Civic facilities; Standard city planning; Surface congestion; Disaster prevention plan; Energy demand.
Pd–Pt–Au alloys were prepared as limited volume electrodes by metal codeposition at constant potential from chloride solutions. Alloy surface state was examined by scanning electron microscopy (SEM) and Auger electron spectroscopy (AES). The alloys were characterized electrochemically in acidic solution (0.5M H2SO4) by cyclic voltammetry (CV). Potential regions of hydrogen electrosorption and surface oxidation are clearly distinguishable. The influence of electrode potential and alloy composition on the amount of absorbed hydrogen was investigated. Hydrogen absorption capacity of Pd–Pt–Au alloys increases with decreasing potential and the α–β phase transition is shifted positively with increasing Au content and negatively with increasing Pt content in the bulk. At relatively high potentials the amount of absorbed hydrogen exhibits a maximum for ca. 15–25at.% Au in the bulk, while for low potentials a monotonic decrease in hydrogen absorption capacity with increasing bulk concentration of both alloying metals (Pt, Au) is observed.
LiNi0.5Mn1.5O4 material with a spinel structure is prepared by a sol–gel method. The material is initially fired at 850°C and then subjected to a post-reaction annealing at 600°C in order to minimize the nickel deficiency. The elevated firing temperature produces materials with a small surface-area which is beneficial for good capacity retention. Indeed, the spinel LiNi0.5Mn1.5O4 not only shows a good cycle performance, but exhibits an excellent discharge capacity, i.e. 114mAhg−1 at 4.66V plateau and 127mAhg−1 in total. Cyclic voltammetry and ac impedance spectroscopy are employed to characterize the reactions of lithium insertion and extraction in the LiNi0.5Mn1.5O4 electrode. Excellent electrochemical performance and low material cost make this compound an attractive cathode for advanced lithium batteries.
Supercapacitor is a promising electrochemical storage system simultaneously having high energy density and high power density. Its performance is significantly affected by electrode materials and the materials’ size, morphology, aggregation state and hierarchical nanostructure which have an effect on electrolyte transportation. Here, the influence of morphology on the capacitive performance of supercapacitor is studied by using polypyrrole (PPy) nanomaterials as model materials. PPy with different morphologies (separated nanodots, vertically aligned nanorods, nanowires and nanomats assembled by random fallen nanowires) are electrodeposited on graphite rods (GR) by potentiostatic polymerization method. The capacitance performance of these prepared PPy/GR electrodes is investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge methods, which exhibits ideal pseudo-capacitance characteristics. Because of the electrolyte diffusion-controlled nature, the high capacitance performance of PPy/GRs can be attained by increasing the effective surface area of the electrode, elevating the test temperature, using high concentration electrolyte and intensifying the process of mass transfer. The experimental results demonstrate that supercapacitors fabricated with separated nanoparticles or vertically aligned nanowires have an ideal capacitor performance. Although the PPy nanomats prepared in this article also has high mass specific capacitances and area specific capacitances, their columbic efficiency becomes lower. To our best knowledge, this is the first report on the effect of morphology on the capacitance performance from the perspective of mass transfer, which gives some new insights on the fabrication of supercapacitor electrodes.
In order to accommodate regenerative braking energy input in hybrid and mild hybrid vehicles while maintaining boosting power at high rates of discharge, valve-regulated lead-acid (VRLA) batteries must operate permanently at partial-state-of-charge (PSoC) conditions. As a consequence, new failure modes appear, e.g., irreversible sulfation in negative plates, that have to be overcome. In this way, work has been done to apply some solutions like improving charge acceptance in this “sulfated medium”. Several batches of 6V 20Ah AGM VRLA batteries with spiral cell design have been assembled and tested, each batch containing novel additives in the negative active material (NAM). It has been observed that the addition of a sufficient amount of expanded graphite significantly improves cycle life under PSoC conditions. Moreover, life duration is also extended, although to a lesser extent, by using a novel fiberglass which increases surface area of NAM.
The oxygen reduction reaction (ORR) on sputtered Pt thin films in acidic solution was successfully studied by scanning electrochemical microscopy (SECM) in a modified tip generation–substrate collection (TG–SC) mode. SECM images of ORR activity in different sample areas were obtained and it is shown that this TG–SC SECM technique can be used to screen electrocatalytic activity of continuous thin film samples efficiently and quickly for the ORR in an acidic medium. It is observed that this technique is not very sensitive to the tip–substrate separation within a certain range. The SECM images obtained are strongly dependent on the substrate potential. The advantages of this technique for studying ORR electrocatalysts are discussed.
Schizophrenia and aging are both risk factors for deficits in independent functioning, yet relatively few studies have examined the level and predictors of functional status of older outpatients with schizophrenia. We compared employment history, current living situation, and driving status of 83 middle-aged and elderly outpatients with schizophrenia (mean age 59 years), and 46 demographically equivalent normal comparison subjects. We also examined the relationships of neuropsychological functioning and psychiatric symptoms to these aspects of everyday functioning. The schizophrenia patient group had consistently worse functional status than the normal comparison group, but 30% of the patients were employed at least 50% of the time during their post-schizophrenia-onset adult lives, 73% were living in a house or apartment and responsible for meeting most of their own daily needs, and 43% were current drivers. Severity of negative symptoms (but not that of positive symptoms) was inversely correlated with functional status. Worse performance on a neuropsychological battery was generally associated with worse functional status. These findings counter notions that functional impairment is inevitable in older schizophrenia patients, and highlight the importance of assessment of functional skills and possibly targeting them as a treatment focus.
Objective To investigate if adjunctive allopurinol reduces symptoms in schizophrenia outpatients with persistent symptoms despite adequate pharmacotherapy. Method N =59 schizophrenia outpatients were randomly assigned to receive adjunctive allopurinol 300 mg bid or identical-looking placebo for 8 weeks after a 2-week placebo run-in. Symptoms were assessed biweekly. Results A total of n =51 patients completed the trial. Including all n =59 randomized patients, a total of 4 of 31 in the allopurinol group and 0 of 28 in the placebo group had at least a 20% reduction in total PANSS score at the final study visit (chi-square=3.88, p =.049). Among the n =51 completers, individuals in the allopurinol group rated themselves as more improved than did those in the placebo group (z =−2.24, p =.025). The allopurinol medication was well tolerated and there were not any adverse events attributed to the study medication. Conclusions Allopurinol may be an effective adjunctive medication for some patients with persistent schizophrenia.
Lithium-sulfur (Li-S) batteries are considered a promising energy storage solution for today’s society, which faces significant energy and environmental issues. Successful implementation of Li-S batteries requires the development of a robust and high-performance sulfur cathode. Unfortunately, the current approaches focus on the development of sulfur-carbon composites without a fundamental understanding of the reduction mechanism of sulfur and the role of carbon. To develop a clear understanding of the efficacy of carbon/sulfur composites, we investigated the electrochemical behavior of Li-S batteries employing different cathode structures. Our comparative study suggests that nanoscale electrical contact between sulfur and carbon is not essential for improving the electrochemical performance of Li-S batteries or for initiating electrochemical redox reactions of the sulfur cathode.