batterydata/paper-abstracts huggingface dataset:
In this paper, metal-organic framework-74-Ni/carbon nanotube (MOF-74-Ni/CNT) composite was synthesized via one-pot in situ hydrothermal reaction. The MOF-74-Ni/CNT was characterized and the electrochemical performance was investigated. The composite sulfur cathode prepared by impregnation method delivers a high initial discharge capacity, good rate capability and a low capacity decay of 0.087% per cycle over 400 cycles at 2 C. The significant electrochemical performance was attributed to the combination of the high affinity of MOF-74-Ni to polysulfide anions and the excellent electronic conductivity of carbon nanotube. These results suggest the design of high polar MOF materials with high conductive CNT is an effective strategy to construct a promising sulfur host for Li-S batteries.
Spinel LiNi0.5Mn1.5O4 is a very important and promising cathode material for lithium ion batteries. The strategy of doping elements is a common used way to improve its electrochemical properties. The action mechanism of doping elements in LiNi0.5Mn1.5O4 is complex. In this study, we synthesized the Cr, Fe-doped compounds LiNi0.45M0.1Mn1.45O4 (M=Cr, Fe) and pristine compound LiNi0.5Mn1.5O4 at the same annealing conditions. The as prepared samples display different morphological features. The thermogravimetric analysis shows different situation for these samples. Oxygen dissipation in the Cr-doped compound at high temperature is less than the other two samples. The XPS spectra display that the doping elements have influences on the chemical valence of Ni, and result in more Ni(III) amount in the Cr, Fe-doped products. The doped compounds exhibit excellent rate capability. At 10C-charge/10C-discharge rate, their capacities are 85mAhg−1, 74mAhg−1 and 50mAhg−1 for LiNi0.45Fe0.1Mn1.45O4, LiNi0.45Cr0.1Mn1.45O4 and LiNi0.5Mn1.5O4, respectively.
A novel solid state route has been successfully developed for the synthesis of nano-scale hydrous ruthenium oxide (denoted as RuO2·xH2O). The procedure involves directly mixing RuCl2·xH2O with alkali to form RuO2·xH2O in a mortar at room temperature. Transmission electron microscopy (TEM) and N2 adsorption–desorption measurement indicate that the RuO2·xH2O particle is approximately 30–40nm with mesoporous structure. The crystalline structure and the electrochemical properties of RuO2·xH2O have been systematically explored as a function of annealing temperature. At lower temperatures, the RuO2·xH2O powder was found in an amorphous phase and the maximum capacitance of 655Fg−1 was obtained by annealing at 150°C. Higher temperatures (exceeding 175°C) presumably converted amorphous phase into crystalline one and the corresponding specific capacitance dropped rapidly from 547Fg−1 at 175°C to 87Fg−1 at 400°C. Also, the dependence of electrochemical performance on annealing conditions of RuO2·xH2O was investigated by electrical impedance spectroscopy (EIS) study.
ABSTRACT Owing to the unique properties of certain Ionic liquids (ILs) as safe and green solvents, as well as the potential of sodium as an alternative to lithium as charge carriers, we investigate gel sodium electrolytes as safe, low cost and high performance materials with sufficient mechanical properties for application in sodium battery technologies. We investigate the effect of formation of two types of gel electrolytes on the properties of IL electrolytes known to support Na/Na+ electrochemistry. The ionic conductivity is only slightly decreased by 0.0005 and 0.0002Scm−1 in the case of 0.3 and 0.5M NaNTf2 systems respectively as the physical properties transition from liquid to gel. We observed facile plating and stripping of Na metal around 0V vs. Na/Na+ through the cyclic voltammetry. A wide-temperature range of the gelled IL state, of more than 100K around room temperature, is achieved in the case of 0.3 and 0.5M NaNTf2. We conclude that the formation of a gel does not significantly affect the liquid-like ion dynamics in these materials, as further evidenced by DSC and FTIR analysis.
Labyrinthine function is tightly coupled to proper homeostasis. Perturbations in labyrinthine microcirculation can lead to significant cochlear and/or vestibular dysfunction. Indeed, no studies were conducted to examine the effect of improvement in cardiac performance after coronary stent application on either hearing or vestibular function. This study included 30 patients presenting to the Catheterization Unit in Sohag University Hospitals. Their age ranged from 41 to 60years. Those patients were suffering from ischemic heart disease and proved to be candidates for Percutaneous Coronary Intervention (PCI) and stenting through a list of pre-operative investigations that included: Electrocardiography (ECG), Echocardiography and Coronary angiography. A full battery of audiovestibular investigations was conducted both preoperatively and postoperatively. Significant differences were encountered between preoperative and postoperative auditory brainstem response (ABR) latency measures, transient evoked otoacoustic emission (TEOAE), vestibular evoked myogenic potentials (VEMP) and Computerized Dynamic Posturography (CDP) tests. Both TEOAE and VEMP proved to be reliable indicators of defective labyrinthine circulation. Severity of chest pain as well as its duration proved to be the best predictors of the degree of total stenosis of coronary arteries. It can be concluded that affection of the labyrinthine peripheral microcirculation is an intimate consequence of deterioration of cardiac output (COP) secondary to ischemic heart disease.
From 12 to 15 December 2002, the area-averaged surface ozone concentrations in south Taiwan increased to 100ppb from a background value of 40. The maximum hourly ozone concentration reached 150ppb on 15 December. GPS-radiosondes, tethered ozonesondes and an instrumented ultralight aircraft were used to measure vertical ozone concentrations and meteorological conditions during this period. An ozone concentration of 60–90ppb was observed in the nocturnal residual layer, 20–50ppb of which was estimated to be produced from local photochemical reactions. Downward mixing of ozone from the residual layer to the ground level was observed in the morning of the episode day. Back air trajectory analysis was performed to locate the source region of the accumulated ozone. The results revealed that the source of high concentration of accumulated ozone was in an ozone-polluted area with an ozone concentration in the range 90–100ppb on the previous day. About 60% of the ozone in the polluted area on the previous day persisted to the morning of the episode day.
Clostridium perfringens is an important animal and human pathogen that can produce more than 16 different major and minor toxins. The beta-2 minor toxin (CPB2), comprising atypical and consensus variants, appears to be involved in both human and animal enterotoxaemia syndrome. The exact role of CPB2 in pathogenesis is poorly investigated, and its mechanism of action at the molecular level is still unknown because of the lack of specific reagents such as monoclonal antibodies against the CPB2 protein and/or the availability of a highly purified antigen. Previous studies have reported that purified wild-type or recombinant CPB2 toxin, expressed in a heterologous system, presented cytotoxic effects on human intestinal cell lines. Undoubtedly, for this reason, to date, these purified proteins have not yet been used for the production of monoclonal antibodies (MAbs). Recently, monoclonal antibodies against CPB2 were generated using peptides designed on predicted antigenic epitopes of this toxin.
Objective: This study was designed to investigate the role of depression, anxiety, and fatigue in Chronic Fatigue Syndrome (CFS) sufferers' objective and subjective cognitive performance. Methods: Twenty-three CFS sufferers and 23 healthy control participants were compared on objective and subjective assessments of cognitive performance. Depression, anxiety, and fatigue were also evaluated. Results: CFS sufferers did not demonstrate any impairment in objective cognitive functioning compared to the control group, and objective performance was not related to their higher levels of depression or their level of fatigue. Depression scores only accounted for a small amount of the variance in CFS sufferers' lower subjective assessment of their cognitive performance compared to control participants. There were no differences between the groups on anxiety scores. Conclusion: The results are discussed in terms of the heterogeneity of the CFS population and the complex interaction of symptomatological factors that characterise CFS.
This paper proposes a novel methodology, QFD based 3D morphological charts, to support variant design of simple and technically mature products. Customer’s requirements are incorporated in developing the morphological charts through a holistic approach, One-Step QFD. In contrast to the traditional cascading deployment, members from marketing, design, and manufacturing teams concurrently derive the requirements from three different aspects. The charts driven by the deployment results produce design concepts of high feasibility through query by function, specification, and module of a product. They are presented in 3D assembly for better visual stimuli rather than clutter of 2D sketches. A computer-aided conceptual design system is implemented to realize the proposed ideas with computer mice as an example product. A design experiment is conducted to compare the quantity and quality of the concepts generated with and without the aid of the system. The results show that it promotes quick generation of innovative concepts while maintaining their manufacturability.
This study has been undertaken to gain a better understanding of how to allow for energy storage in the design of a future built environment where renewable energy systems will play a significant role. Electricity storage solutions are a key element in achieving high renewable energy penetration in the built environment. This paper presents an overview of electricity storage technologies and their distinct characteristics. The currently available technologies have been classified according to the means by which each can be used in supplying energy to buildings. As the storage market is evolving rapidly, the analysis provides an up-to-date evaluation of different storage options with regard to scale, reliability and site-specificity among others. It is concluded that Li-ion batteries, which today have a limited use in the built environment, and Zn–air batteries that will be commercialised in 2013/14 are amongst the most promising technologies for buildings due to their exceptionally high energy density. They are expected to play an important role in reliable, economical and energy efficient building design in the future. NaNiCl batteries, which are currently used in vehicles, are also considered an important technology for buildings, because of their high cycle lifetime and their high peak power capability.
The electrochemical behaviour of ferrocene was studied in different gel polymer electrolytes based on methyl, ethyl and 2-ethoxyethyl methacrylate and compared to the liquid aprotic solution (propylene carbonate). Voltammetric and chronoamperometric measurements on microelectrodes were conducted in order to describe the qualitative as well as quantitative behaviour of ferrocene in different conditions. Heterogeneous electron-transfer rate constants and diffusion coefficients of ferrocene in polymer electrolytes were estimated to be 1.1–7.8×10−3 cms−1 and 4–13×10−8 cm2 s−1 depending on the electrolyte composition. The influence of the polymer polarity, ferrocene concentration and level of polymer cross-linkage on the kinetics of ferrocene oxidation and its transport was discussed. The electrolytes with poly(2-ethoxyethyl methacrylate) exhibit the highest ionic conductivity (2–4×10−4 Scm−1) as well as diffusion coefficient of ferrocene (1.3×10−7 cm2 s−1) in their structure.
This paper analyzes the behavior and studies the thermal degradation phenomena of a novel sodium rich Prussian blue cathode with a sodium deficient and sodium rich anode system viz. amorphous TiO2, crystalline (pristine), and heat treated TiO2 and Na2Ti3O7, respectively. The primary aim of the research was to demonstrate the superiority of the Na2Ti3O7 anode, which in principle can be considered “pre-stressed” by Na atoms when converted from TiO2 to Na2Ti3O7. Another motive of the research was to analyze exhaustively the layered anode structure and its degradation phenomena using the unique technique of thermal imaging to correlate it with post cycled X-ray diffraction (XRD) and an AC impedance study. The Na2Ti3O7 system was seen as more stable than the other tested TiO2 based anodes and produced an open circuit voltage (OCV) of 3.59 V and a maximum specific capacity of 92.18 mAh g−1 when the electrolyte used was dissolved in an organic solvent. Under the same conditions, the TiO2 sample showed an OCV of 3.41 V and a maximum specific capacity of 71.93 mAh g−1. Thermal imaging studies show that the maximum electrochemical degradation occurs at the anode of the samples with the TiO2 sample being more susceptible to corrosion.
This chapter discusses nanocomposites based on carbon nanotubes (CNTs) and metal oxides (MOX) for gas sensing applications. The chapter first reviews the historical background of the MOX and the hybridized MOX/CNT composite gas sensors. It then describes several popular methods for preparation of MOX/CNT sensing films such as spin-coating, drop-coating, screen-printing, dip-coating, and electron beam evaporation techniques. The ways to characterize MOX/CNT materials with their basic theories including raman spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy have been presented. Finally, the sensing mechanism of a MOX/CNT gas sensor based on p–n heterojunctions has been highlighted.
The ionic conductivity of Li x B1−x/3PO4 is investigated in terms of defect models with a lithium doping level of 0<x<0.3. The crystalline solid electrolytes, Li x B1−x/3PO4, are synthesized by a soft-chemical route by using H3BO3, H3PO4, LiOH·H2O. To determine the changes in ionic conductivity and activation energy of Li x B1−x/3PO4 with lithium content x, AC-IS measurements are performed at temperatures between 25 and 90°C. The maximum ionic conductivity is 3.74×10−6 Scm−1 at room temperature for x=0.10, and the activation energy increases from 0.3039 to 0.3385eV with increasing lithium content.
Difficulties with social interaction have been reported in both children with an autism spectrum disorder (ASD) and children with developmental coordination disorder (DCD), although these disorders have very different diagnostic characteristics. To date, assessment of social skills in a DCD population has been limited to paper-based assessment or parent report. The present study employed eye tracking methodology to examine how children attend to socially-relevant stimuli, comparing 28 children with DCD, 28 children with ASD and 26 typically-developing (TD) age-matched controls (aged 7–10). Eye movements were recorded while children viewed 30 images, half of which were classed as ‘Individual’ (one person in the scene, direct gaze) and the other half were ‘Social’ (more naturalistic scenes showing an interaction). Children with ASD spent significantly less time looking at the face/eye regions in the images than TD children, but children with DCD performed between the ASD and TD groups in this respect. Children with DCD demonstrated a reduced tendency to follow gaze, in comparison to the ASD group. Our findings confirm that social atypicalities are present in both ASD and to a lesser extent DCD, but follow a different pattern. Future research would benefit from considering the developmental nature of the observed findings and their implications for support.
All the formats in this book, except this one, deal with programming formats. Panel programs, musical productions, newscasts, and the other formats in this book make specific demands on the director and producer because of what the program is about. In this chapter we'll deal with the demands that stem from the requirements made by the working conditions: specifically working on location, or at a “remote” site … even if the remote site is just next door.
The rapid development of sensor networks for smart industry requires comparable tiny power sources that can deliver high energetic performance and be mass-produced via the existed semi-conductor process. In this paper, novel 3D in-chip micro-supercapacitors (MSCs) based on hierarchical electrodes were developed through silicon-based microfabrication techniques by depositing graphene nanowall (GNW)/ruthenium oxides (RuOx) core-shell hybrids on the silicon scaffolds that are generated from deep reactive ion etching (DRIE). Conformal coating of RuOx on individual graphene nanoflakes was realized via reactive sputtering technique to benefit capacitance enhancement, while the orderly aligned GNW facilitated fast ions and electrons transfer. By harnessing both the merits of huge active surface area of the 3D hierarchical electrode architectures and the excellent electrochemical behaviors of the GNW/RuOx hybrids, the assembled MSCs exhibited areal energy, power densities of 15.1 μWh cm−2 and 2.49 mW cm−2, respectively. In parallel with our novel in-chip strategy by leveraging the bulk volume of Si substrate to create sidewall for effective area enhancement at footprint, the embedment of electrode nanostructures inside the substrate may also give a new concept of MSCs design towards protecting the fragile electrode materials and making the subsequent device encapsulation with ease.
Cobalt nickel double hydroxides (Co x Ni1−x LDHs) nanoparticles were synthesized by a polyvinyl pyrrolidone-assisted chemical co-precipitation method. It was found that the ratio between Co and Ni had a significant effect on their electrochemical activities. The specific capacitance of 2614Fg−1 was achieved when the atomic ratio of Co to Ni was equal to 0.57:0.43. This Co0.57Ni0.43 LDH sample had a BET specific surface area of 109.8m2 g−1 and total pore volume of 0.6036cm3 g−1, and its pore size distribution was mainly in the range of 1.5–5 nm, which led to the high liquid–solid interfacial area and further increased the utilization of the active materials. Additionally, the Co0.57Ni0.43 LDH electrode exhibited a good electrochemical stability with 86.4% of the initial capacitance over 1000 consecutive cycles at 5Ag−1.
A high-performance carbon–Si composite anode for lithium rechargeable batteries was developed. Si powder was coated with amorphous carbon by pyrolyzing polyvinyl chloride and chlorinated polyethylene at 900°C for 2h. The electrochemical performance of the carbon–Si composite anode depended on the Si particle size and the carbon content of the composite. A carbon–nano-size Si (average size 50nm) composite with 48wt.% carbon showed an excellent performance. The coulombic efficiency in the first cycle was 69.2% and the second cycle reversible discharge capacity of 970mAhg−1. The capacity fade on cycling was 0.24% per cycle during the first 40 cycles. The carbon–micron-sized Si (average size 4μm) composite showed a high coulombic efficiency of 78.6% in first cycle, but with poor cycling performance. The capacity fade within 30 cycles was 1.7% per cycle. The effect of the chlorine content in the precursor on the cycling performance was not detectable.
Surface-modified RuO2 nanoparticles–carbon nanofiber (CNF) composites are synthesized using electrospinning and acid treatment in sequence, and their structure, morphology, chemical states, and electrochemical performance are demonstrated. The surface-modified RuO2–CNF composites exhibited the highest specific capacitance of 224.6Fg−1, high-rate performance with capacitance retention of 80%, superior energy density of 26.9–21.5Whkg−1, and excellent cycling stability of 90% after up to 3000 cycles, compared to the conventional CNFs, surface-modified CNFs, and unmodified RuO2 nanoparticles–CNF composites. Their improved electrochemical performance can be explained as synergistic effect of well-distributed RuO2 nanoparticles within the matrix of CNFs and surface modification induced by the increased number of oxygen-containing functional groups, which results in increased capacitance and improved high-rate performance due to Faradaic redox reactions and improved wettability.
Three-dimensional (3D) palladium (Pd) nanostructures (that is, nano-buds or nano-dendrites) are fabricated by bubble dynamic templated deposition of Pd onto a glassy carbon electrode (GCE). The morphology can be tailored by changing the precursor concentration and reaction time. Scanning electron microscopy images reveal that nano-buds or nano-dendrites consist of nanoparticles of 40–70nm in diameter. The electrochemical reduction of oxygen is reported at such kinds of 3D nanostructure electrodes in aqueous solution. Data were collected using cyclic voltammetry. We demonstrate the Pd macroelectrode behavior of Pd nanostructure modified electrode by exploiting the diffusion model of macro-, micro-, and nano-architectures. In contrast to bare GCE, a significant positive shift and splitting of the oxygen reduction peak (vs Ag/AgCl/saturated KCl) at Pd nanostructure modified GCE was observed.
The self-discharge of γ-NiOOH in Ni/Zn primary batteries was studied on real cells and also on chemically simulated ones. The results indicate that it is rooted in a dissolution/re-crystallization process, probably involving an α-type nickel hydroxide intermediate. To minimize this phenomenon, the preparation of a series of diverse metal substituted γ-type nickel hydroxides was attempted by oxidation of α-type precursors containing various amounts of Al, Cd, Co, Cr, Fe or Zn, prepared by direct precipitation at room temperature in an ammonia containing reaction medium. These reactions led to metal substituted γ-type nickel oxihydroxides in all cases except for cadmium and chromium containing samples. For the former phase segregation took place whereas for the latter a complete dissolution of chromium species in the reaction medium was observed. Partial dissolution was found to take place also for aluminium substituted phases. High temperature storage tests conducted on Ni/Zn primary cells using the substituted γ-phases as the positive electrode indicate that iron and cobalt substitution is effective in preventing self-discharge phenomena observed in pure γ-NiOOH, as aged cells presented discharged capacities very similar to fresh cells.
The electricity conversion-efficiency of a solar cell for commercial application is about 6–15%. More than 85% of the incoming solar energy is either reflected or absorbed as heat energy. Consequently, the working temperature of the solar cells increases considerably after prolonged operations and the cell’s efficiency drops significantly. The hybrid photovoltaic and thermal (PVT) collector technology using water as the coolant has been seen as a solution for improving the energy performance. Through good thermal-contact between the thermal absorber and the PV module, both the electrical efficiency and the thermal efficiency can be raised. Fin performance of the heat exchanger is one crucial factor in achieving a high overall energy yield. In this paper, the design developments of the PVT collectors are briefly reviewed. Our observation is that very few studies have been done on the PVT system adopting a flat-box absorber design. Accordingly, an aluminum-alloy flat-box type hybrid solar collector functioned as a thermosyphon system was constructed. While the system efficiencies did vary with the operating conditions, the test results indicated that the daily thermal efficiency could reach around 40% when the initial water-temperature in the system is the same as the daily mean ambient temperature.