batterydata/paper-abstracts huggingface dataset:
A major challenge in designing Internet of Things (IoT) systems is to meet various non-functional requirements such as lifetime, reliability, throughput, delay, and so forth. Furthermore, IoT systems tend to have competing requirements, which exacerbate these design challenges. We analyze this problem in detail and propose a model-driven approach to optimize an IoT application regarding to its non-functional requirements. Our approach defines optimizing as finding the best set of adjustable application parameters, which satisfies a given objective function. The relevant parameters are extracted during a simulation process. We apply a source code transformation that updates the source code with the generated adjustable parameter values and executes the compiler to create a new binary image of the application. Our experiment results demonstrate that non-functional requirements such as power consumption and reliability can be improved substantially during the optimization process.
The aims of this paper are to demonstrate a critical review of the multitude of progress in solar PV research and applications in Bangladesh since its inception in 1996 till 2010. Our studies show that Bangladesh has been experiencing an accelerated shift towards solar PV to meet the gap between demand and supply of electricity along with conventional electricity generation. Despite the present generation of electricity from solar PV is 15–20MW, both public and private sectors have started several solar PV projects to generate several hundred of MW by the upcoming years. This paper has also tried to identify the critical barriers for widespread dissemination of solar PV in Bangladesh and has discussed possible ways to overcome those barriers as well.
Porous solid polymer electrolytes (SPE) were prepared in the form of thin films by phase inversion by direct immersion in non-solvent acetone or methanol, using a copolymer of polyacrylonitrile and poly (vinyl acetate) in ethylene carbonate/dimethylene carbonate (EC/DMC 1:1 v/v) as plasticizer, which contained different LiClO4 percentages. SEM images revealed pores on a micrometer scale (average diameter around 2 μm) distributed inside and on the surface of the films. XRD patterns revealed a predominantly amorphous behavior, favorable to the ionic conduction process. Thin films presented low glass transition temperatures (Tg), between −67 and −58 °C. Thin films showed a thermal stability higher than those obtained for the gels. Thin films (average thickness of 22 μm) showed ionic conductivity around 10−10 S cm−1 and 10−7 S cm−1 by immersion in acetone and methanol, respectively. The porous thin films when were swollen in liquid electrolyte, the maximum ionic conductivity value reached was of 2.5 × 10−4 S cm−1 with 10 % LiClO4 at 25 °C. The oxidation of the SPE only occurred around 4.5 V for the gel and 4.8 V versus Li/Li+ for the SPE thin film, thus resulting in a wide electrochemical stability. A stable passive layer at the interface between the polymer electrolyte and lithium metal was formed within the first 10 h and maintained during 4 weeks. The cell containing LiCoO2 in thin-film electrolyte presented the one well-known plateaux for the Li-ion intercalation in the 4 V region.
Ternary [Li+][MePrPip+][NTf2−] and [Li+][MePrPyrr+][NTf2−] room temperature ionic liquids (ILs) were obtained by dissolution of solid lithium bis(trifluoromethanesulfonyl)imide (LiNTf2) in liquid N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide and N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide, respectively, and studied as electrolytes for the use in Li/LiFePO4 or C(Li)/LiFePO4 batteries. The cell worked properly in the presence of 10 wt% of vinylene carbonate (VC). Impedance-spectroscopy studies showed that the additive (VC) forms a protective coating on the anode. The LiFePO4 cathode shows good efficiency (135 mAh g−1) working together with [Li+][MePrPip+][NTf2−] + VC and [Li+][MePrPyrr+][NTf2−] + VC ionic liquid electrolytes. The flash point of ionic liquid electrolytes containing 10 wt% of VC is above 300 °C, which makes them practically non-flammable.
We demonstrate the electrochemical performance of a lithium-polymer battery comprising P(VDF-HFP) nanocomposite membrane based gel polymer electrolytes (GPE). The nanocomposite membranes are prepared by incorporating ionic liquid functionalized ZnS nanoparticles on to P(VDF-HFP) copolymer. Soaking the membranes into lithium salt dissolved liquid organic solvents transform them into GPEs. Increasing the nanoparticles content gradually improves the porosity and the solvent uptake capacity of the membrane. The optimized membrane with 64% porosity shows highest electrolyte uptake ability of 89% to form a flame-retardant GPE endowing a maximum ionic conductivity of 3.3 mS cm−1 at ambient temperature along with an excellent lithium ion transfer number of 0.62. The cell comprising the optimized GPE with LiFePO4 cathode and Li metal anode shows outstanding electrochemical performance at ambient temperature, delivering a discharge capacity of ∼161 mAh/g at C/10 rate and able to retain its 89% after 50 cycles. The study suggests that conjoining ionic liquid tethered nanoparticles with insulating polymers provides a promising way to produce efficient active polymer membranes based high-performance GPEs, enabling safer, high energy density, lithium-polymer batteries.
The full potential linearized augmented plane wave method with the generalized gradient approximation has been used to understand the electronic and optical properties of α-graphyne-like BN (α-BNyne) sheet. The total and partial density of states, electronic structure and optical constants for different light polarizations are obtained. The optical properties of α-BNyne are found to be strongly anisotropic. For electric field parallel to the α-BNyne sheet, strong optical adsorption and reflectivity are observed in the low-energy region, whiles for the electric field perpendicular to the α-BNyne sheet, the adsorption and reflectivity in the low-energy region are very weak. Also, the results of optical response property calculations show that α-BNyne sheet has broad spectral photoresponse. All of these properties indicate that α-BNyne is a new two-dimensional candidate for use in optoelectronic devices.
Fibromyalgia is a disorder characterized by widespread musculoskeletal pain frequently accompanied by other symptoms such as fatigue. Moderate improvement from pharmacological and non-pharmacological treatments have proposed non-invasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) to the occipital nerve (more specifically the C2 area) or to the dorsolateral prefrontal cortex (DLPFC) as potential treatments. We aimed to explore the effectiveness of repeated sessions of tDCS (eight sessions) targeting the C2 area and DLPFC in reducing fibromyalgia symptoms, more specifically pain and fatigue. Forty-two fibromyalgia patients received either C2 tDCS, DLPFC tDCS or sham procedure (15 C2 tDCS–11 DLPFC tDCS–16 sham). All groups were treated with eight sessions (two times a week for 4 weeks). Our results show that repeated sessions of C2 tDCS significantly improved pain, but not fatigue, in fibromyalgia patients, whereas repeated sessions of DLPFC tDCS significantly improved pain as well as fatigue. This study shows that eight sessions of tDCS targeting the DLPFC have a more general relief in fibromyalgia patients than when targeting the C2 area, suggesting that stimulating different targets with eight sessions of tDCS can lead to benefits on different symptom dimensions of fibromyalgia.
Battery management system monitors and mitigates the operation of battery cells and stacks and is important for battery safety and reliability. This paper presents a dual-objective optimal charging strategy for two types of Li-ion batteries, which considers the conflict objectives of charging time and charging loss. The battery models developed in a prior research are used in the charging optimization. The influences of the charging voltage threshold, temperature, and health status on the charging results are analyzed for both lithium nickel–manganese–cobalt oxide (LiNMC) and lithium iron phosphate (LiFePO4) batteries. A comparison with the charging results based on the models that cannot describe the entire battery dynamics is also performed.
There is a net discharge of water and nutrients through Long Key Channel from Florida Bay to the Florida Keys National Marine Sanctuary (FKNMS). There has been speculation that this water and its constituents may be contributing to the loss of coral cover on the Florida Keys Reef tract over the past few decades, as well as speculation that changes in freshwater flow in the upstream Everglades ecosystem associated with the Comprehensive Everglades Restoration Plan may exacerbate this phenomenon. The results of this study indicate that although there is a net export of approximately 3,850 (±404) ton N year−1 and 63 (±7) ton P year−1, the concentrations of these nutrients flowing out of Florida Bay are the same as those flowing in. This implies that no significant nutrient enrichment is occurring in the waters of the FKNMS in the vicinity of Long Key Channel. Because of the effect of restricted southwestward water flow through Florida Bay by shallow banks and small islands, the volume of relatively high-nutrient water from central and eastern portions of the bay exiting through the channel is small compared to the average tidal exchange. Nutrient loading of relatively enriched bay waters is mediated by tidal exchange and mixing with more ambient concentrations of the western Florida Bay and Hawk Channel. System-wide budgets indicate that the contribution of Florida Bay waters to the inorganic nitrogen pool of the Keys coral reef is small relative to offshore inputs.
The LiNi0.5Mn1.5O4 with different morphologies have been successfully prepared through co-precipitation route in mixed solution containing 1-dodecyl-3-methylimidazolium bromide ([C12mim]Br) and H2O with different mass ratios and followed by a solid reaction at high temperature. The morphology of LiNi0.5Mn1.5O4 varies with the increasing ratio of [C12mim]Br. These samples synthesized at three kinds of concentrations present flake-like morphology, agglomerated flake-like structure and polygon particles with size about 700nm, respectively. The as-prepared LiNi0.5Mn1.5O4 with polygon structure presents the highest discharge capacity. The optimal LiNi0.5Mn1.5O4 sample was modified with 1, 3 and 5wt.% CuO, respectively. The electrochemical testing results demonstrate 3wt.% CuO-modified material had the capacity retention of higher than 95% after 100 cycles, and high capacity of 98.7 mAh g−1 at 10C rate, in comparison with the capacity retention of 83% and capacity of 63.6 mAh g−1 for the pristine one. The remarkably improved rate performance and cycling stability can be attributed to CuO coating, which acts as an effective lithium-ion conductor and a protective material against corrosion from electrolyte.
ABSTRACT We carried out physical-chemical and electrochemical characterizations of lithium naphthalenide solutions in tetrahydrofuran (THF) in view of their potential use as liquid anode material in rechargeable batteries. Concentrations of dissolved naphthalene and lithium were varied to prepare homogeneous solutions of general formulae LixN(THF)n; 0≤x≤2 and 3<n<25. FTIR investigations support a two-step mechanism for LixN(THF)n formation. For 0<x< 1 the solutions consist of mixture of lithium-free naphthalene Li0N(THF)n and lithium-bound naphthalene Li1N(THF)n whereas for 1<x<2 the solutions consist of mixture of Li1N(THF) and Li2N(THF)n solutes. Electrical conductivity traces (σ(x, n)) make a maximum at x∼1 in diluted solutions (n>10) and at x∼0.5 for more concentrated ones (n<10). The highest σ value of 12.4 mS/cm is achieved in Li0.5N(THF)6.2 composition. The conductivity of LixN(THF)10.4 solutions shows linear behaviour with temperature of with negative slopes highlighting its metal-like character. We found a logarithm law of viscosity with ‘x’, a common feature in amorphous systems. Entropy and enthalpy measurements were performed in a Li/Ceramics/Li1N(THF)10.4 half-cell by monitoring open-circuit potentials (OCP) changes in the temperature range of 25°C – 10°C. A full cell consisting of Li1N(THF)10.4 anode and a iodine based liquid cathode was successfully tested to proof the concept of a new all liquid electrodes refillable lithium batteries.
Objective: To test the hypothesis that stunted Nepalese children have an altered stress response system when compared with matched nonstunted children in response to a battery of psychological tests.
Heteroatom-doping has been regarded as an effective strategy to regulate the Na storage performance of carbon materials. In this paper, N and O dual-doped carbon microspheres (NO-CS) from the rinds of corn stalks have been fabricated via a tailored carbonization and solution doping route. NO-CS reveals both high O (15.6 at.%), N (6.4 at.%) contents and high specific surface area (746.48 m2 g−1). The NO-CS derived carbon anode shows tremendous reversible capacity, rate capability and cycling stability, e.g. 270 mAh g−1 over 200 cycles at 50 mA g−1, 130 mAh g−1 over 3500 cycles at 5 A g−1. The superior Na storage property may due to the abundant porosity and dual-doping that boost fast ion adsorption at the graphene layer defects and nitrogen oxygen moiety of carbon. Scalable and cost-effective synthesis route with outstanding Na storage performance makes NO-CS a competitive anode material for Na-ion batteries.
Through targeted and reproducible electrochemical treatment of glassy carbon electrodes, investigations have been carried out on the electrochemical behaviour of the oxidation of V2+, VO2+ and the reductions of VO2 +, VO2+ and V3+ in order to pretreat electrodes specifically for use in vanadium redox flow batteries and, if possible, to treat them in situ. For this purpose, a glassy carbon electrode was treated potentiostatically for a period of 30 s at different potentials in the range of 500 mV–2000 mV vs. Hg/Hg2SO4 in 2 M H2SO4 and then linear sweep voltammograms were performed in the different vanadium-containing solutions. With this method, it could be shown that all reactions are extremely surface sensitive and the reaction speeds changed by several decades. The reaction rates increased significantly in all reactions compared to polished electrodes and had an optimum treatment potential of approx. 1600 mV vs. Hg/Hg2SO4, although the oxidation reaction of V2+ and the reduction reactions of V3+ and VO2+ had opposite tendencies to oxidation of VO2+ and the reduction of VO2 + in the area of low treatment potentials. In the former, the kinetics increased and in the latter, they decreased. In addition, causes were investigated using confocal microscopy and XPS. No correlation was found to the roughness or size of the stretched surfaces, although these changed significantly as a result of the treatment. XPS measurements gave indications of a dependence on hydroxyl groups for the oxidation of VO2+ and the reduction of VO2 +, while for the reactions of oxygen-free cations and the reduction of VO2+ weak indications of a dependence on carboxyl groups were obtained.
The pharmacokinetic (PK) profile of nicotine delivered by an Electronic Vapour Product (EVP) was characterised in a 2-part study in smokers. The study was designed as a randomised, controlled, four-way crossover trial. Part 1 compared an unflavoured e-liquid (UF2.0%) and a flavoured e-liquid (FL2.0%) to a conventional cigarette (CC; JPS Silver King Size, 0.6 mg) and a licensed nicotine inhalator (Nicorette®; 15 mg). Part 2 compared e-liquids with increasing nicotine concentrations (0%, 0.4%, 0.9%, 2.0%). Subjects used each different product for a daily use session. In Part 1, maximum plasma nicotine concentration (Cmax) for UF2.0%, FL2.0%, Nicorette® and CC was 3.6, 2.5, 2.5 and 21.2 ng/mL, respectively. The time to maximum plasma nicotine concentration (Tmax) was longer for the EVP (UF2.0%, 9.0 min; FL2.0%, 10.0 min) and the nicotine inhalator (13.0 min) compared to CC (3.0 min). In Part 2, EVP with 0%, 0.4%, 0.9% and 2.0% nicotine produced Cmax values of 0.6, 1.0, 1.9 and 3.6 ng/mL, respectively. At the maximum nicotine concentration of 2% as prescribed by the European Tobacco Directive, the EVP achieved nicotine delivery that was comparable to the inhalator. EVPs thus offer a potential alternative to nicotine inhalator devices for those finding it difficult to quit smoking.
At the level of individual experience, the relation between electroencephalographic (EEG) phenomena and subjective ratings of psychological states is poorly examined. This study investigated the correlation of quantitative EEG markers with systematic high-frequency monitoring of psychological states in patients admitted to the epilepsy monitoring unit (EMU). We used a digital questionnaire, including eight standardized items about stress, energy level, mood, ward atmosphere, seizure likelihood, hopefulness/frustration, boredom, and self-efficacy. Self-assessments were collected four times per day, in total 15 times during the stay in the EMU. We extracted brainrate, Hjorth parameters, Hurst exponent, Wackermann parameters, and power spectral density from the EEG. We performed correlation between these quantitative EEG measures and responses to the 8 items and evaluated their significance on single subject and on group level. Twenty-one consecutive patients (12 women/9 men, median age: 29 years, range: 18–74 years) were recruited. On group level, no significant correlations were found whereas on single-subject level, we found significant correlations for 6 out of 21 patients. Most significant correlations were found between Hjorth parameters and items that reflect changes in mood or stress. This study supports the feasibility of correlating quantitative EEG measures with psychological states in routine EMU settings and emphasizes the need for single-subject statistics when assessing aspects with high interindividual variance. Future studies should select samples with high within-subject variability of psychological states and examine a subsample with patients encountering a critical number of seizures needed in order to relate the psychological states to the ultimate question: Are psychological states potential indicators for seizure likelihood?
Environmental pollution and energy deficiency are two key issues for the sustainable development of the modern society. Polyurethane foam is a typical commercial polymer with a large production quantity and its waste needs to be recycled. Lithium–sulfur battery is a promising energy-storage device with high energy density and low cost, but its demerits such as poor conductivity of the sulfur and severe capacity degradation due to the soluble lithium polysulfides are still a big challenge. This work reports a facile method to prepare nitrogen-doped porous carbon (NPC) from the polyurethane foam (PUF) waste and use it as a reservoir to impregnate sulfur for lithium–sulfur batteries. The obtained NPC has a unique interconnected sheet-like porous morphology with a large surface area of 1315 m2 g−1. The NPC-S composite delivers a large reversible capacity of 1118 mAh g−1 with good cycling performances and excellent high-rate capabilities. A large reversible capacity of 460 mAh g−1 can be retained at a large current of 5C (8.35 A g−1) after 100 cycles.
Our power system is evolving in the form of small entities called Microgrids. In this scenario, different renewable and conventional energy sources are integrated together to form the Microgrid and to satisfy a specific load. The frequency is an indication of the balance between the generation and the demand. In the conventional power system, the generators are used to balance the frequency. The emerging new technologies such as the Plug-in-Electric vehicles can play a great role in the stability of the load frequency control system. In this paper, the stability of a Microgrid with plug-in-electric vehicles and communication delay is investigated. The Microgrid controller communicates wirelessly with the plug-in electric vehicle and they form a kind of time delay system. A Microgrid model with plug-in electric vehicles and communication delay is presented in this paper. Lyapunov-Krasovskii functional is used to derive stability criterion in form of Linear Matrix Inequalities. Through solving the Linear Matrix Inequalities the maximum time delay that guarantees the stability of the Microgrid is determined. The parameters that affecting the stability and the maximum allowable delay are determined which are; the PI controller gains, the Microgrid inertia, the PEV gain and the PEV time constant.
For the construction of an all-electric race car, all aspects from engineering design over cost estimation up to the road capability are illuminated. From the most promising batteries for electric vehicle propulsion, the state-of-the art and commercial availability of lithium-ion secondary batteries is critically discussed with respect to cycle-life and unfavorable charge–discharge conditions. A market-overview is given with respect to a small electric car. Different combinations of electric motors and a recuperation system have been investigated. Weight aspects of central drive systems were considered and compared with decentralized wheel-hub drives. As a result, a centralized high-speed drive train based on a permanent-magnet synchronous engine with high-energy magnets seems to be superior due to limited space for assembly.
Mg2−x Al x Ni thin films (x =0, 0.1, 0.2, 0.3) are prepared by magnetron sputtering. Their charge–discharge properties are tested, and the effects of Al partial substitution for Mg on the change of the enthalpy of hydrides formation and electrochemical properties are discussed. The charge–discharge experiments show that the discharge properties of the Mg2Ni film are improved by the substitution of Al for Mg. The change of the enthalpy of hydrides formation of the Mg2−x Al x Ni film decrease with the increase of Al content, which indicate that the stability of the Mg2−x Al x Ni film hydrides decrease with the increase of Al content. The potentiodynamic polarization results show that the anti-corrosion property of Mg2Ni thin film is improved with the partial substitution of Al for Mg. Electrochemical impedance spectra studies suggest that the oxide layer thickness decrease with Al substitution, and the charge-transfer resistance of the film electrode increase from 202Ω (Mg2Ni) to 1474Ω (Mg1.6Al0.4Ni) which indicates that the reaction rate at the electrode surface decrease.
Collections of deletion mutants are important tools for functional genomics in crops. In order to establish an efficient physical γ-ray-based mutagenesis protocol and estimate the frequency of induced chromosome deletion events in apple, we mutagenized a total of 338 leaves of the apple cultivar ‘Golden Delicious’ with a range of irradiation doses (from 0 to 30 Gy). After in vitro culture and regeneration, a total of 248 plantlets were genotyped by a custom-made 384 SNP-based array suited to identify homozygous regions, corresponding to chromosome deletions produced by the irradiation and/or the in vitro culture treatments. With this approach, we identified nine multi-SNP chromosome deletions corresponding to 3.7 % of all regenerated plantlets and ranging from one to 44 cM (0.1–20.2 Mb). Chromosome deletions were also observed at mildly, not significantly lower frequency in plantlets regenerated from non-irradiated leaves. Our results confirm the possibility to generate apple plants with sizeable deletions of known dimension and location, opening the way to creating a collection of deletions spanning the apple genome useful for functional genomics. The high frequency of deletions apparently caused by somaclonal variation deserves further investigation.