batterydata/paper-abstracts huggingface dataset:
Zn-doped LiZn y Ni0.8−y Co0.2O2 (0.0000≤y≤0.0100) compositions were synthesized by a conventional solid-state method. The products were characterized by XRD, galvanostatic cycling, cyclic voltammetry, electrochemical impedance spectroscopy and thermal analysis. For the LiZn0.0025Ni0.7975Co0.2O2 system cycled between 3.0 and 4.2V, the discharge capacities in the 1st and 100th cycles were 170 and 138mAh/g with charge retention of 81%. The corresponding values for the undoped material were 158 and 97mAh/g, with charge retention of 61.4%. The improved electrochemical properties of the doped system were attributed to the structural stability derived from incorporating the size-invariant Zn2+ ions. The Zn-doped system also showed improved capacity and cyclability when the cycling was performed in a voltage wider window (2.5–4.4V) and at a higher temperature (55°C). The structural and electrochemical properties of the doped and undoped materials were correlated.
The design of a novel differential scanning calorimeter (DSC) sample crucible that allows for the analysis of liquid and solid materials (the solids can also be wetted with a liquid) at high temperatures is described. The sample to be analyzed is placed within a thin walled stainless steel tube, which is then sealed by tungsten inert gas (TIG) welding. The stainless steel tube is 8.8mm (0.35in.) long, has an outer diameter of 3.14mm (0.125in.) and a wall thickness of 0.015mm (0.006in.). Placing the flattened end of the tube in the jaws of a large copper block (heat sink) allows for the sealing of the tube by TIG welding without heating the sample excessively. The utility of the sample crucible is demonstrated by a study of the kinetics of the thermal decomposition of di-t-butyl peroxide (DTBP), where an activation energy of 140kJmol−1 and a frequency factor of 5.30×1013 s−1 was obtained.
This paper describes a method of simulating an assembly operation in a fully immersive virtual environment in order to analyze the postures of workers as they perform assembly operations in aerospace manufacturing. The challenges involved in capturing the movements of humans performing an assembly operation in a real work environment were overcome by developing a marker-based motion capture system and using it in a cave automatic virtual environment (CAVE). The development of the system focuses on real-time human motion capture and automated simulation for ergonomic analysis. Human movements were tracked in a CAVE, with infrared (IR) LEDs mounted on a human body. The captured motion data were used to generate a simulation in real-time and perform an ergonomic analysis in Jack software. The simulation also included the use of Microsoft Kinect as a marker-less human body capture system for the purpose of scaling the digital human model in Jack. The developed system has been demonstrated for human motion capture and ergonomic analysis for the fastening operation of an aircraft fuselage.
In order to systematically study how the arrangement of cations on the side chain and length of alkyl spacers between cations impact the performance of multi-cation AEMs for alkaline fuel cells, a series of polyphenylene oxide (PPO)-based AEMs with different cationic side chains were synthesized. This work resulted in samples with two or three cations in a side chain pendant to the PPO backbone. More importantly, the length of the spacer between cations varied from 3 methylene (-CH2-) (C3) groups to 8 methylene (C8) groups. The highest conductivity, up to 99 mS/cm in liquid water at room temperature, was observed for the triple-cation side chain AEM with pentyl (C5) or hexyl (C6) spacers. The multi-cation AEMs were found to have decreased water uptake and ionic conductivity when the spacer chains between cations were lengthened from pentyl (C5) or hexyl (C6) to octyl (C8) linking groups. The triple-cation membranes with pentyl (C5) or hexyl (C6) groups between cations showed greatest stability after immersion in 1 M NaOH at 80 °C for 500 h.
Background and aims Most information on the neuropsychological performance of pediatric patients with temporal lobe epilepsy (TLE) is derived from selected surgical series. Non-lesional pediatric TLE patients were studied here at the population level in order to investigate the extent to which neuropsychological deficits predisposing to learning difficulties exist in this more common group. Methods Language, memory and executive functions were measured in children aged 8–15 years with non-lesional TLE and of normal intelligence (n = 21), and their performance was compared with that of healthy age and gender-matched children (n = 21). The effects of clinical epilepsy variables on performance were examined. Results Although neuropsychological performance did not differ between the TLE patients and the healthy controls, female gender, early onset, longer duration and abnormal interictal EEG had a negative effect on neuropsychological performance. Conclusions Children with early-onset epilepsy should be assessed carefully for neuropsychological impairment using sufficiently broad batteries of tests in order to detect even slight deficits. Our sample size was small and these findings should be interpreted as preliminary results and need to be confirmed in larger studies.
In this paper, the design of a “low cost full passive structure” of wind turbine system without active electronic part (power and control) is investigated. The efficiency of such device can be obtained only if the design parameters are mutually adapted through an optimization design approach. For this purpose, sizing and simulating models are developed to characterize the behavior and the efficiency of the wind turbine system. A model simplification approach is presented, allowing the reduction of computational times and the investigation of multiple Pareto-optimal solutions with a multiobjective genetic algorithm. Results show that the optimized wind turbine configurations are capable of matching very closely the behavior of active wind turbine systems which operate at optimal wind powers by using a MPPT control device.
The internal temperatures of 25 households in Northern Ireland were measured in each house at four locations: the bedrooms, living rooms, halls and kitchens, and analysed on seasonal, monthly and daily bases. In 80% of the homes the winter average daily temperature was between 15°C and 20°C and in summer between 20°C and 23°C, therefore maintaining a reasonably comfortable temperature throughout the year. In 14% of the homes, the daily average temperature was above 21°C throughout the year, suggesting a higher household temperature than required for comfort, thus exhibiting wasteful energy behaviour. Three percent of the homes did not use their heating adequately and the winter average temperature was below 15°C. For the majority of households, the highest indoor temperature was in August and the lowest in February. In general the peak temperatures of households occur in the evening after 8:00pm. The peak bedroom temperatures occur between 10:00pm and midnight and in the morning after 8:00am. The peak living room temperature is generally in the evening while it is occupied. Correlations between the temperature difference between indoor and outdoor temperatures with outdoor temperature have been developed for each house and the four locations. The relationship between the fluctuations of average daily temperature with annual average temperature has been established.
The present paper presents several experimental results regarding the electrodeposition and corrosion behavior of Sn and NiSn alloy coatings from some choline chloride based ionic liquids, applied onto various metallic substrates including Cu and steel. There are discussed electrolytes containing Sn and Ni salts in choline chloride–ethylene glycol and choline chloride–malonic acid eutectic mixtures. The obtained Sn and Ni–Sn alloy deposits are adherent and uniform onto metallic substrates The Ni–Sn alloys contained about 62–72wt% Sn according to EDX analysis, with a very slight variation against the applied current density domain. According to XRD investigations both electrochemical coatings showed a nanocrystalline structure, with average sizes of the crystallites between 50 and 80nm for Sn and around 11–14.5nm for NiSn alloy. To evaluate corrosion resistance of Sn and Ni–Sn alloy coatings, potentiodynamic polarization curves and electrochemical impedance spectra (at open circuit potential) in 0.5M NaCl solution have been recorded after different immersion times of coated specimens. Different corrosion performances are discussed taking into account the used electrodeposition procedures.
That emotional memory enhancement is compromised in adult patients with temporal lobe epilepsy (TLE), particularly in the case of early cerebral damage, has been suspected. We conducted a study in which we compared 20 children and adolescents aged 11–15years with early TLE with 40 healthy control subjects. We studied the effect of emotional information on verbal memory performance using story recall and word list learning tasks. Our results highlighted the existence of emotional memory facilitation in healthy subjects, whereas there was no beneficial impact of emotional material on memory in young patients with TLE. Our study suggests that early TLE can impair the development of emotional memory processes.
Thermal stability of Li-ion cells (from two different manufacturers, A and B) and their cathodes and anodes were evaluated as a function of state of charge (SOC) using accelerating rate calorimetry (ARC). Cell A was rated at 750mAh and consisted of Sn-doped LiCoO2 cathode and meso-carbon micro-fiber (MCMF) anode. Cell B was rated at 790mAh and was comprised of a cathode and an anode made of LiCoO2 and graphite. The electrolytes in cells A and B were mixtures of EC:EMC + 1MLiPF6 and EC:EMC:DMC + 1MLiPF6, respectively. ARC results indicated that between 50 and 125% SOC, the total heat generated by cell A is mostly dominated by self-heating of the cathode, while between 125 and 200% SOC the total heat generated by the cell was dominated by the anode. The total heat generated in cell B, however, was dominated by self-heating of the graphite anode, over the entire 50–200% SOC range. Also, the self-heating in cell B was higher than that for cell A. Heat generation of the LiCoO2 increases with increasing SOC, and the Sn-LiCoO2 heat generation reaches a maximum near 125% SOC. At low SOC, the temperature of the onset of chemical reaction (T OSCR) for cell A was higher than that for the cell B. For both cells, at higher SOC, T OSCR decreased with a sharp drop between 100 and 150% SOC. Overall results show that cell A offers a higher thermal stability than cell B. Also, the ARC test is more suitable than differential scanning calorimetry for correlation of cathode and anode heat generations to the thermal performance of full Li-ion cells.
Despite advances in expression technologies, the efficient production of heterologous secreted proteins in Escherichia coli remains a challenge. One frequent limitation relies on their inability to be exported to the E. coli periplasm. However, recent studies have suggested that translational kinetics and signal sequences act in concert to modulate the export process.
Lithium-ion capacitors are considered as a promising energy storage device to combine the high energy of lithium-ion batteries and high power of supercapacitors, and it is urgently required to evaluate the energy storage capability of lithium-ion capacitors from practical perspectives. In this work, a pouch-type lithium-ion capacitor is constructed using commercial SiOx/graphite as anode and activated carbon as cathode. Due to the outstanding tap density and electrical conductivity of SiOx/graphite anode, the reversibility and charge storage of lithium-ion capacitor pouch is greatly improved, which can function stably within a wide voltage window of 1–4 V to achieve a maximum gravimetric energy and power density of 29.3 Wh kg−1 and 6 kW kg−1, respectively (based on the total weight of pouch). Moreover, the volumetric energy and power density of this pouch also reach 50 Wh L−1 and 10 kW L−1 (based on the total volume of pouch), respectively. The achievement of both gravimetric and volumetric energy performances promises a bright future for of lithium-ion capacitors toward electrical applications where large energy-storage in limited space is demanded.
A Sb/graphene nanohybrid has been synthesized by a facile in situ solvothermal route using SbCl3 and graphite oxide as the precursors and NaBH4 as the reducing agent. Microstructural observation reveals the sheet-like nanostructure consisting of Sb nanocrystals (50–100 nm) attached on few-layer graphene nanosheets. The in situ introduced graphene uniformly disperses the Sb nanocrystals, while the attached Sb nanocrystals hinder the restacking of the graphene nanosheets. The introduction of graphene remarkably improves the electrochemical Li and Na-storage properties of Sb due to the combined buffering, confining and conducting effects of graphene. The underlying mechanism for the enhanced Li and Na-storage properties has been investigated by chemical diffusion coefficient and electrochemical impedance spectroscopy measurement.
Exposure of keratinocytes (KC) to ultraviolet (UV) radiation results in the initiation of apoptosis, a protective mechanism that eliminates cells harboring irreparable DNA damage. Hence, a manipulation of UV-induced apoptosis may significantly influence photocarcinogenesis. We have discovered that the aryl hydrocarbon receptor (AHR), a key regulator of drug metabolism and an UVB-sensitive transcription factor, serves an anti-apoptotic function in UVB-irradiated human KC. Chemical and shRNA-mediated inhibition of AHR signaling sensitized KC to UVB-induced apoptosis by decreasing the expression of E2F1 and its target gene checkpoint kinase 1 (CHK1). The decreased expression of these cell-cycle regulators was due to an enhanced expression of p27KIP1 and an associated decrease in phosphorylation of both cyclin-dependent kinase 2 and its substrate molecule retinoblastoma protein. The subsequent inhibition of E2F1 autoregulation and downstream CHK1 expression resulted in an enhanced susceptibility of damaged cells to undergo apoptosis. Accordingly, ectopic overexpression of either E2F1 or CHK1 in AHR-knockdown KC attenuated the observed sensitization to UVB-induced apoptosis. Using an AHR-knockout SKH-1 hairless mouse model, we next demonstrated the physiological relevance of the anti-apoptotic function of AHR. In contrast to their AHR-proficient littermates, the constitutive expression of E2F1 and CHK1 was significantly reduced in the skin of AHR-knockout mice. Accordingly, a single exposure of the animals to UVB resulted in an enhanced cleavage of caspase-3 in the skin of AHR-knockout mice. These results identify for the first time the AHR-E2F1-CHK1 axis as a novel anti-apoptotic pathway in KC, which may represent a suitable target for chemoprevention of non-melanoma skin cancer.
In this study, we examined changes in EEG signals during the cognitive activity at different air temperatures and relative humidities (RH). Thirty-two healthy young people acclimatized to the subtropical climate of Changsha, China, were recruited as subjects. They experienced four air temperature levels (26, 30, 33, and 37 °C) and two relative humidity levels (50 and 70%) in a climate chamber. During 175 min-long exposures to each thermal condition, they performed cognitive tasks and their EEG signals were measured. Relative humidity of 70% and increased temperature at this relative humidity significantly increased the relative power of δ-band and significantly decreased relative power of θ-band, α-band, and β-band. This may suggest that subjects were more sleepy but less drowsy, and it was more difficult for them to think clearly. At the same time, subjective evaluations indicated that they could be less alert and it was harder for them to think. However, no changes in performance of tasks measuring cognitive abilities were observed. It remains therefore unclear whether EEG can be a credible marker of changes in cognitive activity as a result of changes in indoor environmental quality in buildings and the future experiments should closely examine this issue.
All-solid-state (ASS) lithium-ion battery has attracted great attention due to its high safety and increased energy density. One of key components in the ASS battery (ASSB) is solid electrolyte that determines performance of the ASSB. Many types of solid electrolytes have been investigated in great detail in the past years, including NASICON-type, garnet-type, perovskite-type, LISICON-type, LiPON-type, Li3N-type, sulfide-type, argyrodite-type, anti-perovskite-type and many more. This paper aims to provide comprehensive reviews on some typical types of key solid electrolytes and some ASSBs, and on gaps that should be resolved.
Livestock grazing is one of the most widespread types of anthropogenic land use, even occurs in many protected areas and has become a threat to wildlife worldwide. Understanding livestock-wildlife interactions is crucial for rare large carnivores conservation. In China, free-ranging cattle within forests degrade the habitat of the tigers (Panthera tigris) and leopards (Panthera pardus), but quantitative assessments of how livestock affect the spatial and temporal use by the major ungulate prey of the two endangered felids are very limited.
The 3000 plus islands of New England with their varying electrical needs and high electricity costs present an opportunity for renewable energy development. This paper summarizes the results of ongoing wind energy projects carried out by the University of Massachusetts for the development of renewable energy on several of these islands. In addition to technical–economic issues, the work has addressed potential environmental and political problems that might arise with the installation of such systems. Summaries of four selected case studies involving this work are given in this paper. The overall analysis method used to study each of these studies is described, and the example case studies present a status of the work to date on each of these projects.
The study area is a small coastal plain in north-eastern Tunisia. It is drained by an ephemeral stream network and is subject to several pollutant discharges such as oilfield brine coming from a neighboring oil company and wastewater from Somâa city, located in the upstream of the plain. Furthermore, a hydraulic head near the coastal part of the aquifer is below sea level, suggesting that seawater intrusion may occur. A time-domain electromagnetic (TDEM) survey, based on 28 soundings, was conducted in Wadi Al Ayn and Daroufa plains to delineate the saline groundwater. Based on longitudinal and transversal resistivity two-dimensional pseudosections calibrated with boring data, the extent of saline water was identified. Geochemical tracers were combined with the resistivity dataset to differentiate the origin of groundwater salinization. In the upstream part of the plain, the infiltration of oilfield brine through the sandy bed of Wadi Al Ayn seems to have a considerable effect on groundwater salinization. However, in the coastal part of the aquifer, groundwater salinization is due to seawater intrusion and the saltwater is reaching an inland extent around 1.3 km from the shoreline. The contribution ratios of saline water bodies derived from the inverted chloride data vary for the oilfield brine from 1 to 13 % and for the seawater from 2 to 21 %.
Carbon-coated Li3VO4 sample is synthesized by a simple sol–gel method. X-ray diffraction and X-ray photoelectron spectroscopy results show that single-phase Li3VO4 can be obtained in a reducing atmosphere with the valence of vanadium of +5. The final product sintered at 650 °C demonstrates a favorable electronic conductivity with 6.12% residual carbon. Electrochemical testing shows that the carbon-coated Li3VO4 sample display a discharge capacity of 662.6 mAh g−1 and 507.4 mAh g−1 at 0.18C in the first and the second cycle, respectively, and a reversible capacity (charge capacity) of ∼480.0 mAh g−1 can be obtained in the second cycle. Furthermore, the discharge–charge capacity of the sample can retain ∼180 mAh g−1 and ∼90 mAh g−1 at 12C and 40C, respectively.
Rechargeable lithium-oxygen (Li-O2) batteries have appeal to enormous attention because they demonstrate higher energy density than the state-of-the-art Li-ion batteries. Whereas, their practical application is impeded by several challenging problems, such as the low energy round trip efficiencies and the insufficient cycle life, due to the cathode passivation caused by the accumulation of discharge products. Developing efficient catalyst for oxygen reduction and evolution reactions is effective to reduce the overpotentials in Li-O2 cells. In our work, we report a Co3O4 modified Ag/g-C3N4 nanocomposite as a bifunctional cathode catalyst for Li-O2 cells. The g-C3N4 substrate prevents the accumulation of Ag and Co3O4 nanoparticles and the presence of Ag NPs improves the surface area of g-C3N4 and electronic conductivity, significantly improving the oxygen reduction/evolution capabilities of Co3O4. Due to a synergetic effect, the Ag/g-C3N4/Co3O4 nanocomposite demonstrates a higher catalytic activity than each individual constituent of Co3O4 or Ag/g-C3N4 for the ORR/OER on as catalysts in Li-O2 cells. As a result, the Ag/g-C3N4/Co3O4 composite shows impressive electrochemical performance in a Li-O2 battery, including high discharge capacity, small gap between charge and discharge potential, and high cycling stability.
Sulfur–carbon nano-composites were prepared by two methods: thermal treatment and mechanical milling. The resulted composites were characterized by scanning electron microscopy, X-ray diffraction and Brunauer–Emmett–Teller. The structures and electrochemical properties of the composites were decided by the preparation methods and sulfur contents. By thermal treatment, most part of sulfur could be embedded in the micro pores of the active carbon. Combined with polymer electrolyte, the composites with favorable sulfur contents exhibited high specific capacity up to 800 mA h g−1 in the initial cycle and a stable reversible capacity approximately 440 mA h g−1. The utilization of electrochemically active sulfur was about 90% assuming a complete reaction to the product of Li2S.
Challenges remain in understanding battery processes that govern operation and limit performance, but fundamental research holds the key for further development of beyond-lithium-ion technologies.
Complete polarization curves for a number of heteropoly acids (HPAs), H3PW12O40, α-H3P2W18O62, H6P2W21O71, and H6As2W21O69 as the only proton conducting component are presented for the first time. Both thin pellets of HPA and composite membranes of 1:1 (w/w) of HPA and polyvinylidenedifluoride–hexafluoropropylene (PVDF–HFP) are investigated. Although the pellets are somewhat variable, the HPA phase changes can be observed by electrochemistry and these materials show promise for solid acid fuel cell performance at >200°C. The high proton conductivities reported for HPAs at RT are demonstrated in fuel cells using HPA/PVDF–HFP composites with limiting current densities as high as 1.6Acm−2 using dry O2 and H2. Moderate fuel cell activity is demonstrated for α-H3PW18O62 at 120°C and 25%RH. Unfortunately all of the materials studied were somewhat porous and the open circuit potentials observed were somewhat low. We were also able to show that an HPA fuel cell could be shorted by reduction of the HPA to a heteropoly blue under exceptional circumstances.