batterydata/paper-abstracts huggingface dataset:
LiNi1−y Al y O2 (0.10≤y≤0.50) compounds have been synthesized by a coprecipitation method. The characterization of the samples by X-ray and neutron diffraction, associated with Rietveld refinement analysis, has shown that for all materials, about 5% extra-nickel ions are present in the interslab space. Charge−discharge cycling of LiNi1−y Al y O2 as positive electrode material in lithium cells has shown that aluminum substitution suppresses all the phase transitions observed for the LiNiO2 system. Good cycling stability was observed, but the capacity decreases from 125 to 100mAh/g by increasing the aluminum amount from 10 to 25% (3–4.15V range; C/20 rate).
This study develops a urea-based homogeneous precipitation method to synthesize spherical carbonate precursors (Ni0.25Mn0.75CO3) for the Li-rich layered cathode material Li(Ni0.2Li0.2Mn0.6)O2. The structure and morphology of the precursor particles were tailored by controlling of urea concentration, reaction temperature and time. Combined with XRD, SEM, and particle size analysis, the optimized conditions for synthesizing desired stoichiometric Ni0.25Mn0.75CO3 were obtained. We also investigated the processes of nucleation and growth of precursors. The obtained spherical Li(Ni0.2Li0.2Mn0.6)O2 delivers discharge capacity of 237 mAh g−1 at the initial cycle and 253 mAh g−1 after 50 cycles.
We use AC impedance methods to investigate the effect of mechanical deformation on ion transport in commercial separator membranes and lithium-ion cells as a whole. A Bruggeman type power law relationship is found to provide an accurate correlation between porosity and tortuosity of deformed separators, which allows the impedance of a separator membrane to be predicted as a function of deformation. By using mechanical compression to vary the porosity of the separator membranes during impedance measurements it is possible to determine both the α and γ parameters from the modified Bruggeman relation for individual separator membranes. From impedance testing of compressed pouch cells it is found that separator deformation accounts for the majority of the transport restrictions arising from compressive stress in a lithium-ion cell. Finally, a charge state dependent increase in the impedance associated with charge transfer is observed with increasing cell compression.
Publisher Summary This chapter describes the homeostatic model for the motivation to maintain subjective well-being (SWB). Motivation arises from conditions that challenge the maintenance of SWB and is strongly linked with two aspects of the model: personality and needs. The general idea of the proposed homeostatic system is that SWB is managed, for each individual, within a set-point range. Each person has a built-in set-point for their normal level of SWB and their perceived SWB is normally held within a narrow range around this setting. At the level of individuals, homeostasis predicts that people who suffer some event that depresses their SWB below the threshold should improve their levels of SWB over time. It is found that, if the initial level of SWB fell within the normal range of values, improved extrinsic circumstances will not be reﬂected in higher levels of SWB. It is found that under extrinsic threat conditions, on the other hand, the control of SWB is predicted to shift, ﬁrst, to the homeostatic system of buffers and then when homeostasis is defeated to the threatening agent itself, as it causes SWB to fall below its normal range.
Road freight transportation is a key enabler of global economic activity while also a central consumer of fossil fuels, which presents a challenge in realising a low-carbon future. To identify feasible decarbonisation solutions, we first assess significant drivers of activity in the road freight sector. We then use these drivers to project road freight service demand, vehicle stock, mileage, sales, final energy demand, and well-to-wheel GHG emissions using the IEA’s Mobility Model (MoMo) under two scenarios – the first incorporating the policy ambition of the Nationally Determined Contributions pledged at COP21, and the second extending ambitions to emission reductions that are in line with limiting global temperature rise to 1.75 degrees. In the former scenario, road freight well-to-wheel GHG emissions increase by 56% between 2015 and 2050, while in the latter, sectoral emissions are reduced by 60% over the same period, reflecting our assessment of the threshold of emission reductions potential. This reduction is catalysed by policy efforts including fuel economy regulations, carbon taxes on transport fuels, differentiated distance-based pricing, widespread data-sharing and collaboration across the supply chain as enabled by digital technologies, and sustained investment in ultra-low and zero-carbon infrastructure and research development and deployment.
Based on the results of the experimental study in Part I [1], a holistic simulation model that combines electrical and thermal simulation of electrochemical double-layer capacitor (EDLC) modules with an ageing model is presented. This simulation model allows analysing self-accelerating degradation effects caused by elevated voltages and temperatures. Furthermore, the divergence of cell performance in a stack of cells can be investigated which makes the model a valuable tool for cell and stack design as well as for testing operating strategies and cooling systems.
In this study, we aimed to evaluate the attentional and executive functions in patients with benign childhood epilepsy with centrotemporal spikes (BCECTS) with and without attention-deficit hyperactivity disorder (ADHD) compared with controls and compared with patients with ADHD without epilepsy. We evaluated 12 patients with BCECTS and ADHD (66.7% boys; mean age of 9.67years); 11 children with non-ADHD BCECTS (63.6% boys; mean age of 11.91years); 20 healthy children (75% boys; mean age of 10.15years); and 20 subjects with ADHD without epilepsy (60% boys; mean age of 10.9years). We used a comprehensive battery of neuropsychological tests to evaluate attentional and executive functions in their broad domains. Patients with BCECTS and ADHD had worse performance in Conners' Continuous Performance Test II (reaction time standard error [p=0.008], variability [p=0.033], perseverations [p=0.044] and in reaction time interstimuli interval [p=0.016]). Patients with ADHD showed worse performance in Trail Making Test B errors [p=0.012]. In conclusion, patients with BCECTS and ADHD had worse executive and attentional performance compared with controls than non-ADHD patients with BCECTS. Regardless of the presence of epilepsy, ADHD also negatively impacted executive and attentional functions but in different executive subdomains compared with patients with epilepsy.
Nonfluent (NFV) and semantic (SV) variants of primary progressive aphasia (PPA) are associated with distinct patterns of focal cortical atrophy and underlying pathology. Previous diffusion tensor (DT) MRI studies showed a more ventral white matter (WM) involvement in SV patients and a more widespread frontal involvement in NFV. Aim of this manuscript is twofold. First, we wished to provide a brief state-of-the-art review on WM damage in PPA. Second, we used DT MRI to assess the topography of WM microstructural damage along dorsal and ventral language pathways and corpus callosum in patients with NFV and SV. Our findings show that the two PPA variants share an overlapping pattern of dorsal and ventral pathway abnormalities. In addition to these common abnormalities, variant-specific WM changes were also found, with NFV patients having a more severe damage to the dorsal (fronto-parietal) WM connections within the left superior longitudinal fasciculus/arcuate and SV patients showing a greater left ventral tract involvement (inferior longitudinal and uncinate fasciculi). These findings offer evidence that both dorsal and ventral language networks may contribute to the relatively selective deficits in NFV and SV patients.
A new hybrid electrochemical capacitor based on an activated carbon negative electrode, lead dioxide thin film and nanowire array positive electrode with an electrolyte made of a lead salt dissolved in methanesulfonic acid was investigated. It is shown that the maximum energy density and specific capacity of the C/PbO2 nanowire system increase during the first 50 cycles before reaching their maximum values, which are 29Whkg−1 and 34Fg−1, respectively, at a current density of 10mAcm−2 and a depth of discharge (positive active electrode material) of 3.8%, that corresponds to a 22C rate. This is 7–8 times higher than the corresponding maximum values reached with a C/PbO2 thin film cell operated in the same conditions. After an initial activation period, the performances of the C/PbO2 nanowire system stay constant and do not show any sign of degradation during more than 5000 cycles. For comparison, the C/PbO2 thin film system exhibits a 50% decrease of its performances in similar conditions.
Even after its being phased out in gasoline in the late 90s, lead (Pb) is still present at relatively high levels in the atmosphere of Beijing, China (0.10–0.18μgm−3). Its origin is subject to debate as several distinct sources may contribute to the observed pollution levels. This study proposes to constrain the origin(s) of Pb and strontium (Sr) in aerosols, by coupling both Pb and Sr isotope systematics. The characterisation of the main pollution sources (road traffic, smelters, metal refining plants, coal combustion, cement factories, and soil erosion) shows that they can unambiguously be discriminated by the multi-isotope approach (206Pb/204Pb and 87Sr/86Sr). The study of total suspended particulates (TSP) and fine particles (PM2.5) from Beijing and its vicinity indicates that both size fractions are controlled by the same sources. Lead isotopes indicate that metal refining plants are the major source of atmospheric lead, followed by thermal power stations and other coal combustion processes. The role of this latter source is confirmed by the study of strontium isotopes. Occasionally, emissions from cement plants and/or input from soil alteration are isotopically detectable.
Poor storage property and the rapid moisture hinder the application of LiNi0.8Co0.1Mn0.1O2 due to the formation of Li2CO3/LiOH impurities and a spontaneous reduction of Ni3+ to Ni2+ on the surface. Alcohol washing is desirable to improve the electrochemical performance, storage characteristics and structural stability of LiNi0.8Co0.1Mn0.1O2. Electrochemical studies indicate that washed material exhibits a higher discharge capacity (148mAhg−1 at 8C) and better capacity retention at 2C (79.2% after 100 cycles) compared with the un-treated material after storage in air for 40 days. Inductively coupled plasma (ICP) tests show the amount of metal dissolution decreases compared with the un-washed sample. The Rietveld refinement results indicate that the Li/Ni cationic disorder can be reduced from 0.0714 to 0.0538 by alcohol washing after storage. Transmission electron microscope (TEM), Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) indicate alcohol washing contributes LiNi0.8Co0.1Mn0.1O2 much resistant to H2O and CO2, which further reduce the formation of Li2CO3 and maintain structural stability during the storage process.
The availability of drinking water is reducing day by day; where as the requirement of drinking water is increasing rapidly. To overcome this problem there is a need for some sustainable source for the water distillation (purification). Solar still is a useful device that can be used for the distilling of brackish water for the drinking purposes. In this article a review has been done on different types of solar still.
According to present evolution trends for ICE vehicles, different architectures of the vehicle electric powernet and improved energy storage systems are required. In particular, the use of a 36V as nominal voltage for the powernet, in addition to the conventional 12V one, will be needed to face the increasing power demand caused by fuel consumption reduction needs, comfort and safety concerns. This will require developments in the field of batteries. In this paper, the trends of development of the electric powernets on conventional vehicles are described along with future system architectures and battery requirements. This last topic includes technical aspects related to the sizing, performance, operating voltage range, technologies proposed, management system and safety concerns.
Metal sulfides have been drawing more and more attention as electrode materials in batteries due to their high theoretical capacities. However, the volume expansion and loss of active materials are two major problems, hindering further improvement in their electrochemical performances. Herein, a strategy based on physical confinement/chemical adsorption is proposed to fabricate CoS and Co9S8 electrodes for advanced lithium batteries. Via a facile two-step method, porous C/CNT micro/nano-spheres embedding cobalt sulfide nanoparticles are successfully fabricated, in which sulfur is immobilized by CS bonds. Physically, the porous C/CNT micro/nano-spheres well accommodate the volume change and inhibit the loss of active materials. Chemically, the sulfur species are anchored by CS bonds to alleviate the migration and loss. Assembled as lithium battery anodes, the porous cobalt sulfide/carbon composites, particularly the CoS/C/CNT (CoS-0.4C) and Co9S8/C/CNT (Co9S8-0.8C), exhibit superior lithium storage properties to those without any complexing or any CS bonding. Furthermore, an in-situ electrochemical measurement is proposed to detect the existence of Li2S, which is helpful to understand the mechanism of conversion reaction-based metal sulfides.
Lithium iron phosphate (LiFePO4) is recognized as being less stable and easily dissolvable in aqueous suspensions, particularly when the suspension pH is adjusted to be more alkaline or acidic. In this investigation, an unexpected and interesting finding is revealed, which contradicts the conventional understanding of the dissolution of LiFePO4. As most of the surface of commercial LiFePO4 is coated with carbon, the key factor determining its dissolution behavior is the chemical quality of the surface carbon. With more sp2-bonded carbon on the surface, both the dissolution and electrochemistry of LiFePO4 are independent of pH variations in aqueous suspensions. When the surface carbon is mainly sp3-bonded, LiFePO4 exhibits distinct dissolution and electrochemical properties at different pH levels and, under alkaline conditions, shows greater dissolution and poorer cell performance than that characterized mainly by sp2-bonded carbon.
Solar and wind energy systems are omnipresent, freely available, environmental friendly, and they are considered as promising power generating sources due to their availability and topological advantages for local power generations. Hybrid solar–wind energy systems, uses two renewable energy sources, allow improving the system efficiency and power reliability and reduce the energy storage requirements for stand-alone applications. The hybrid solar–wind systems are becoming popular in remote area power generation applications due to advancements in renewable energy technologies and substantial rise in prices of petroleum products. This paper is to review the current state of the simulation, optimization and control technologies for the stand-alone hybrid solar–wind energy systems with battery storage. It is found that continued research and development effort in this area is still needed for improving the systems’ performance, establishing techniques for accurately predicting their output and reliably integrating them with other renewable or conventional power generation sources.
This paper proposes an efficient approach based on Virus colony search (VCS) algorithm to optimize the sizing and placement of stand-alone hybrid power system including photovoltaic solar panels (PV) and battery bank in system which employ diesel generators (DGs) as pilot source of electrical energy formatting hybrid system. The optimization is carried out to incessantly satisfy the load demand. Two objectives have been defined: the reduction of the equalized cost system (economic objective) and equalized CO2 equivalent life cycle emissions (environmental objective). In the optimization problem, the dependability index of not supplied energy (NSE) is also considered to have a reliable system. The VCS algorithm is an effective and powerful approach that has fast convergence and high precision. This algorithm simulates diffusion and infection strategies for the host cells adopted by virus to survive and propagate in the cell environment. With the policies, the individual in the new algorithm explores and exploits the search space more professionally. This study is applied to Fort-Lotfi City: Tindouf (South of Algeria) that still needs access to National grid electricity due to economic and geography matters. The results prove the advantages of hybrid power systems in isolated locations ranging from being cost effective and reducing the accumulated emissions. The proposed algorithm is compared with PSO and MPSO algorithms which confirm its best performance and effectiveness.
Purpose To compare the efficacy and visual results of phacoemulsification vs manual sutureless small-incision extracapsular cataract surgery (SICS) for the treatment of cataracts in Nepal. Design Prospective, randomized comparison of 108 consecutive patients with visually significant cataracts. Methods settings: Outreach microsurgical eye clinic. patients: One hundred eight consecutive patients with cataracts were assigned randomly to receive either phacoemulsification or SICS. intervention Cataract surgery with implantation of intraocular lens. main outcome measures: Operative time, surgical complications, uncorrected and best-corrected visual acuity (BCVA), astigmatism, and central corneal thickness (CCT). Results Both surgical techniques achieved excellent surgical outcomes with low complication rates. On postoperative day 1, the groups had comparable uncorrected visual acuity (UCVA) (P = 0.185) and the SICS group had less corneal edema (P = 0.0039). At six months, 89% of the SICS patients had UCVA of 20/60 or better and 98% had a best-corrected visual acuity (BCVA) of 20/60 or better vs 85% of patients with UCVA of 20/60 or better and 98% of patients with BCVA of 20/60 or better at six months in the phaco group (P = 0.30). Surgical time for SICS was much shorter than that for phacoemulsification (P < .0001). Conclusion Both phacoemulsification and SICS achieved excellent visual outcomes with low complication rates. SICS is significantly faster, less expensive, and less technology dependent than phacoemulsification. SICS may be the more appropriate surgical procedure for the treatment of advanced cataracts in the developing world.
The entropy changes (ΔS) in various cathode and anode materials, as well as in complete Li-ion batteries, were measured using an electrochemical thermodynamic measurement system (ETMS). LiCoO2 has a much larger entropy change than electrodes based on LiNi x Co y Mn z O2 and LiFePO4, while lithium titanate based anodes have lower entropy change compared to graphite anodes. The reversible heat generation rate was found to be a significant portion of the total heat generation rate. The appropriate combinations of cathode and anode were investigated to minimize reversible heat generation rate across the 0–100% state of charge (SOC) range. In addition to screening for battery electrode materials with low reversible heat, the techniques described in this paper can be a useful engineering tool for battery thermal management in stationary and transportation applications.
This paper discusses the performance characteristics of two types of cells of configuration LiMn2O4/chitosan/C. LiMn2O4 was prepared by the sol–gel method. The precursor obtained was heated at different temperatures to form LiMn2O4. The performance of the LiMn2O4 compound prepared at different temperatures was investigated by studying the discharge characteristics of the LiMn2O4/LiClO4–EC-DMC/C cells. It was found that the cell utilising LiMn2O4 obtained by heating the precursor at 600°C, for 6h gave the best performance. The LiMn2O4 compound was then used to fabricate cells using a chitosan-based electrolyte. In one of the cells, the chitosan polymer was doped with 32% salt to represent a salt-in-polymer electrolyte and in the other, the polymer was doped with 75% salt to form a polymer-in-salt electrolyte. The room temperature conductivity for the salt-in-polymer electrolyte was 1.3×10−5 Scm−1 and that of the polymer-in-salt electrolyte was 3.9×10−3 Scm−1. The cathode of all cells consists 80% active material 10% binder and 10% carbon by weight. The characteristics of the cells were measured and analysed.
Supercritical CO2 (SCCO2) fluid, exhibiting gas-like diffusivity, extremely low viscosity, and near-zero surface tension, is used to synthesize uniformly dispersed and tightly anchored SnO2 nanoparticles (a 3-nm diameter was achieved) on graphene nanosheets (GNSs). Usually, the conventional synthesis processes (in the absence of SCCO2) results in aggregated SnO2 clusters; whereas the technique described in this work eliminates this limitation. This study reveals the significance of two crucial factors (the SCCO2 pressure (i.e., fluid density) and the degassing step (i.e., vacuuming stage) in autoclave before injecting CO2) on the uniform distribution of the synthesized SnO2 nanoparticles on GNSs. Increasing the pressure leads to an increase in SCCO2 density (and viscosity), suppressing the transport of SnO2 precursors throughout the sample. On the other hand, vacuuming the autoclave before injecting CO2 improves the uniformity of SnO2 particle distributions. To assess the electrochemical performance of the synthesized nanoparticles, the specific capacity, rate capability, and cyclic stability were determined for various samples. A capacity of ∼787 mAh g−1 at 100 mA g−1 was achieved for an optimal configuration of the SnO2/GNS electrodes. The capacity retention was 60% when the charge‒discharge rate increased to 6000 mA g−1.
To promote the performance of the batteries used in hybrid vehicles, an effective test profile is needed. A test profile could also improve the efficiency of battery development research efforts. This paper proposes a test profile for battery equivalence research, which can accurately simulate practical operating conditions and make inconsistency among batteries. The proposed test profile is based on practical data acquired from the hybrid Polymer Electrolyte Membrane (PEM) fuel cell buses demonstrated at the 2010 Shanghai World Expo. The control strategy of the demonstration buses is first explained, followed by presentation of maps of the acquired data. Using the maps, the practical conditions are discussed. Importantly, a “Three-Ridge” map style is proposed by analyzing the current density statistics. Additionally, a fast Fourier transform (FFT) analysis of the battery current is adopted to find the conversion frequency of the current in practical conditions. Based on these analyses, a credible battery test profile for hybrid PEM fuel cell buses is proposed. Finally, an experiment verifies that the proposed test profile can simulate the practical operating conditions of a hybrid vehicle battery pack.