batterydata/paper-abstracts huggingface dataset:
Thermal and electrochemical processes in a 1000mAh lithium-ion pouch cell with a graphite anode and a Li x CoO2 cathode during a safety test are examined. In overcharge tests, the forced current shifts the cell voltage to above 4.2V. This causes a cell charged at the 1C rate to lose cycleability and a cell charged at the 3C rate to undergo explosion. In nail penetration and impact tests, a high discharge current passing through the cells gives rise to thermal runaway. These overcharge and high discharge currents promote joule heat within the cells and leads to decomposition and release of oxygen from the de-lithiated Li x CoO2 and combustion of carbonaceous materials. X-ray diffraction analysis reveals the presence of Co3O4 in the cathode material of a 4.5V cell heated to 400°C. The major cathode product formed after the combustion process cells abused by forced current is Co3O4 and by discharge current the products are LiCoO2 and Co3O4. The formation of a trace quantity of CoO through the reduction of Co3O4 by virtue of the reducing power of the organic solvent is also discussed.
Real-time activity measurements from multiple specific cell populations and projections are likely to be important for understanding the brain as a dynamical system. Here we developed frame-projected independent-fiber photometry (FIP), which we used to record fluorescence activity signals from many brain regions simultaneously in freely behaving mice. We explored the versatility of the FIP microscope by quantifying real-time activity relationships among many brain regions during social behavior, simultaneously recording activity along multiple axonal pathways during sensory experience, performing simultaneous two-color activity recording, and applying optical perturbation tuned to elicit dynamics that match naturally occurring patterns observed during behavior.
Hierarchical mulberry-like iron-cobalt sulfide (Fe3S4/Co9S8) nanoparticles were conveniently fabricated through etching the FeCoAl alloy in mild conditions followed by one-step facile sulfurization process. The as-made sulfide nanoparticles are composed of interconnected tiny particles and numerous pore channels as the building subunits. Coupling with the hierarchical nanostructure and the synergistic effects between the dual sulfides, the Fe3S4/Co9S8 composite demonstrated the outstanding lithium storage performances in terms of superior reversible capacity, good rate performance, and exceptional cycling stability. The specific capacity of 945 mAh g−1 could be reserved over Fe3S4/Co9S8 composite at 100 mA g−1 after 100 cycles. More importantly, upon long-term cycles for 1500 loops under the high rate of 2000 mA g−1, the specific capacity of the as-made sulfide still retained as high as 519 mAh g−1. Fe3S4/Co9S8 composite presents prospective application potential in the field of energy storage technologies.
In this paper we investigate the problem of uneven energy consumption in a large class of many-to-one sensor networks. In a many-to-one sensor network, all sensor nodes generate constant bit rate (CBR) data and send them to a single sink via multihop transmissions. This type of sensor network has many potential applications such as environmental monitoring and data gathering. Based on the observation that sensor nodes sitting around the sink need to relay more traffic compared to other nodes in outer sub-regions, our analysis verifies that nodes in inner rings suffer much faster energy consumption rates (ECR) and thus have much shorter expected lifetimes. We term this phenomenon of uneven energy consumption rates as the “energy hole” problem, which may result in severe consequences such as early dysfunction of the entire network. We proposed analytical modeling for this problem, which can help understand the relevance of different factors on energy consumption rates. Using this model, we study the effectiveness of several existing approaches towards mitigating the “energy hole” problem, including deployment assistance, traffic compression and aggregation. We have used simulation results to validate our analysis.
Abstract From the very beginning, nature used hydrothermal processes to create fuels during various geological and biological eras involved in the formation of our planet. We then intensively used such fuels for societal development. Like any inheritance, we have the responsibility to pass them on to further generations. However, the rate at which we have used such nonrenewable fuels is enormous, despite their initial abundance. As a consequence, Earth’s environment today is in danger because of dramatic increase in CO2 associated with burning fossil fuels. Although, as few as 300 years ago humans subsisted almost entirely on renewables, our habits have progressively changed, and by the end of the twentieth century we became 100% dependent on fossil fuels. Besides damaging the ecosystem, such fossil resources are unevenly distributed geographically, and therefore, the price of oil today bears no relationship to its production cost. We clearly need to move away from fossil fuels in order to prevent further damage of the planet. A viable and environmentally safe alternative to fossil fuels needs to be available for the future generations. As nature made fossil fuels hydrothermally, it makes sense to learn from such natural processes. Biomass is the most available renewable resource on Earth, and therefore it should become the main source for future renewable energy. In this chapter, we present an overview of sustainable and viable hydrothermal transformations of biomass into artificial coal and related materials, or hydrothermal carbon.
The present paper introduces a new method to prepare nano-NiOOH by oxidizing and cracking spherical Ni(OH)2 of nano-structure in NaClO–NaOH solution. The prepared samples were characterized by X-ray powder diffraction (XRD), field emission scan electronic microscope (FESEM) and transmission electron microscopy (TEM). Results indicate that the synthesized sample is nano-NiOOH rod of 60–150nm in width. The charge/discharge tests show that the nano-NiOOH cathode shows good cycling reversibility at high current density of 10,000mAg−1, provides a high capacity of 276mAhg−1 and reduces the charge time to as short as 1.83min. Furthermore, the nano-NiOOH still keeps a reversible capacity of 93.7% after 120 cycles at a super high charge/discharge current of 10,000mAg−1, showing a good charge/discharge property.
Clinical observation has proven that anxiety disorders frequently appears in Bone Marrow transplant (BMT) patientes. It was decided to conduct a study within the psychological transplant preparation program (PTPP), where the pre-transplant anxiety level was measured. A standardized psychological test battery and a semi-structured interview were conducted on a group of 20 pediatric patients (5 females/ 15 males, between 6 -18 years old) during the first session prior to receiving any kind of PTPP. A record was kept: Age, gender, diagnostic date, hospital stay, clinical complications and family dynamic. Hypothesis testing was conducted so as to compare percentages, establishing a specificity level ƒÑ of 0.5 and a power of 0.8; therefore, estimation according to the sample size, 20 patients, plus (less) 20% of losses during enrollment was done. Regarding central distribution measurements, hypothesis testing was conducted so as to compared means with paired ¡V T. Based on the results, a therapeutic support plan is developed for handling the patient¡¦s anxiety. Out of the 20 patients assessed, 80% of the patients have a high anxiety level compared to their chronological age, according to what the anxiety scale evaluates. 70% of patients had the highest number of anxiety indicators within the tests. The statistical analysis showed that variables: a) clinical complications, b) hospital stay and c) family dynamics were the ones that had a 90% influence in patients anxiety. Secondly, age, gender and diagnostic date were factors that influenced the anxiety status in 64% of the cases. It is concluded that the anxiety level in BMT patients is high from the moment they start the process, therefore, it is important to give them coping techniques and in this way prevent psychological complications in the next stages.
Potentiostatic intermittent titration technique (PITT) has been used to study the lithium ion insertion into LiFePO4 from aqueous 2M Li2SO4 electrolyte along with cyclic voltammetry and electrochemical impedance spectroscopy (EIS) techniques. The current–time response to an applied potential step has been discussed for lithium insertion into LiFePO4 from aqueous electrolyte and it is compared with that obtained with an organic electrolyte. The PITT technique is very useful in describing the whole intercalation mechanism. The effects of ohmic potential drops and charge-transfer resistances have been taken into account while predicting the current transients obtained with aqueous electrolyte and non-aqueous electrolyte. The deviation of current transients from ideal Cottrell behavior has been discussed in aqueous electrolyte and it is compared with that in presence of non-aqueous electrolyte. The characteristic diffusion time constant (t o) in 2M Li2SO4 is found to be 4.71s and that in non-aqueous LiAsF6/EC–DMC electrolyte is 248s. The chemical diffusion coefficient (D), an important kinetic parameter, calculated from PITT during intercalation process is found to be varying between 10−12 and 10−14 cm2 s−1 in aqueous electrolyte and between 10−13 and 10−15 cm2 s−1 in non-aqueous electrolyte.
Two CeO2/carbon nanotube composites were prepared in both basic and neutral medium thus using different deposition procedures of the cerium oxide. The modification of the synthesis conditions varied the hydrolysis rate of the cerium oxide precursor, leading to materials with different morphology, texture and surface chemistry, significantly changing their electrochemical performance. The different mechanisms of charge storage occurring on the surface of the materials were thoroughly studied to investigate the origin of the observed changes in the electrochemical properties. To that end, a combination of sweep wave voltammetry and deconvolution analysis in acid (1M H2SO4), basic (1M NaOH) and neutral (1M Na2SO4) electrolytes was conducted. The faradaic activity of the composite prepared by slow hydrolysis (containing well-dispersed and small ceria particles) is enhanced as compared with the composite prepared by fast hydrolysis, which originates bulky particles.
An account is given of the lithium-ion (Li-ion) battery pack used in the Northern Territory University's solar car, Fuji Xerox Desert Rose, which competed in the 1999 World Solar Challenge (WSC). The reasons for the choice of Li-ion batteries over silver–zinc batteries are outlined, and the construction techniques used, the management of the batteries, and the battery protection boards are described. Data from both pre-race trialling and race telemetry, and an analysis of both the coulombic and the energy efficiencies of the battery are presented. It is concluded that Li-ion batteries show a real advantage over other commercially available batteries for traction applications of this kind.
The effect of water washing on LiNi0.8Co0.1Mn0.1O2 cathode is extensively studied with respect to the electrochemical properties, structural stabilities, and storage characteristics. Water washing can improve the cycling performance and structural stability of LiNi0.8Co0.1Mn0.1O2 material in electrolyte, although with a slight deleterious effect on the capacity. Storage tests of the 4.3 V charged electrodes at 90 °C after 30 days show that Ni, Co, Mn in fresh and washed samples are dissolved in electrolyte, but the amount of dissolved Ni4+ ions after washing decreases by 31.5% compared with the fresh cathode. Moreover, the fresh sample transforms into the spinel phase with a Fd3m space group, whereas the washed sample remains as a layered hexagonal phase with an Rm 3 ¯ space group. FTIR spectroscopy, transmission electron microscope (TEM), X-ray diffraction (XRD) and electrochemical studies indicate that the washed materials become more easily attached upon exposure to air, accompanied by significant increase in cationic disorder and NiO-like cubic phase near surface.
A novel approach for integrating a pseudo-two dimensional electrochemical thermal (P2D-ECT) model and data assimilation algorithm is presented for lithium-ion cell state estimation. This approach refrains from making any simplifications in the P2D-ECT model while making it amenable for online state estimation. Though deterministic, uncertainty in the initial states induces stochasticity in the P2D-ECT model. This stochasticity is resolved by spectrally projecting the stochastic P2D-ECT model on a set of orthogonal multivariate Hermite polynomials. Volume averaging in the stochastic dimensions is proposed for efficient numerical solution of the resultant model. A state estimation framework is developed using a transformation of the orthogonal basis to assimilate the measurables with this system of equations. Effectiveness of the proposed method is first demonstrated by assimilating the cell voltage and temperature data generated using a synthetic test bed. This validated method is used with the experimentally observed cell voltage and temperature data for state estimation at different operating conditions and drive cycle protocols. The results show increased prediction accuracy when the data is assimilated every 30s. High accuracy of the estimated states is exploited to infer temperature dependent behavior of the lithium-ion cell.
Search boxes providing simple keyword-based search are insufficient when users have complex information needs or are unfamiliar with a collection, for example in large digital libraries. Browsing hierarchies can support these richer interactions, but many collections do not have a suitable hierarchy available. In this paper we present a number of approaches for automatically creating hierarchies and mapping items into them, including a novel technique which automatically adapts a Wikipedia-based taxonomy to the target collection. These approaches are applied to a large collection of cultural heritage items which is formed through the aggregation of other collections and for which no unified hierarchy is available. We investigate a number of novel user-evaluated metrics to quantify the hierarchies’ quality and performance, showing that the proposed technique is preferred by users. From this we draw a number of conclusions as to what makes a hierarchy useful to the user.
The decrease in capacity at low temperature limits further application of lithium-ion batteries. This paper introduces an approach to compensating the capacity loss of Li4Ti5O12 (LTO) based lithium-ion batteries at low temperature by increasing the charging cut-off voltage. The impact of this approach on battery durability is examined afterwards, and a “tipping point” voltage for degradation is observed. Cut-off voltages over the tipping point (3.2 V) cause severe degradation, while those beneath the tipping point do not. The degradation mechanisms are studied with incremental capacity (IC) curve analysis, a prognostic and mechanistic (P&M) model and Scanning Electron Microscope/X-Ray Energy Dispersive Spectrometer (SEM/EDS) tests. Analysis show that the potential of the LTO anode first drops below 1 V when the battery is overcharged to 3.2 V. The electrolyte exceeds the reduction potential and decomposes on the LTO surface, forming Solid Electrolyte Interface (SEI) film with gas generation. The anode potential then gradually rises to above 1 V as we continue to charge the battery. However, the cathode potential exceeds 4.6 V, resulting in electrolyte oxidation and active material loss in the cathode. Overall, enhancing the cut-off voltage from 2.7 V to 3.2 V is effective to enlarge the charging capacity (9.5%) of the LTO batteries at −20℃ with slight degradation.
The scholarship on responsible research and innovation (RRI) aims to align the processes and outcomes of innovation with societal values by involving a broad range of stakeholders from a very early stage. Though this scholarship offers a new lens to consider the challenges new health technologies raise for health systems around the world, there is a need to define the dimensions that specifically characterise responsible innovation in health (RIH). The present article aims to introduce an integrative RIH framework drawing on the RRI literature, the international literature on health systems as well as specific bodies of knowledge that shed light on key dimensions of health innovations. Combining inductive and deductive theory-building strategies and concomitant with the development of a formal tool to assess the responsibility of innovations, we developed a framework that is comprised of nine dimensions organised within five value domains, namely population health, health system, economic, organisational and environmental. RIH provides health and innovation policy-makers with a common framework that supports the development of innovations that can tackle significant system-level challenges, including sustainability and equity.
Dependencies of viscosity (η) and conductivity (κ) on temperature and solvent composition are examined for solutions of LiPF6 and of LiClO4 in ethylene carbonate (EC):diglyme (DG) binary mixtures to identify organic electrolyte systems with the highest conductivity as possible at room temperature. The energies of activation for viscous flow and for conductivity, determined as functions of the composition of the mixed solvent, show these two transport processes to be strongly related. Conductivities of electrolyte solutions prepared with LiPF6 and LiClO4 are comparable, but lower activation energy is required for LiClO4. A flat maximum of conductivity at about 50% (v/v) in EC is observed when the composition of the mixed solvent is varied. A high value, independent of the considered temperature, has been found for the product κ η, meaning that free ions are the predominant ionic species in these media. As a consequence, the macroscopic viscosity of electrolytes under study mainly governs their conductivity. Cyclic voltammetry, performed on negative (Li x C) and positive (Li x NiO2) intercalation electrodes in the optimized electrolyte (LiClO4 or LiPF6 (1 M)-50:50 EC:DG), gives evidence for the formation of passive layers during the first cycle and reversible electrochemical intercalation during the following cycles. DSC results show that this electrolyte system is a potential candidate for Li secondary batteries or electrochromic devices working at ambient or higher temperatures as it is safe and stable at least to 200°C.
Post-fermentation treatments may begin almost immediately after fermentation. These may involve any necessary adjustments to the wine’s physicochemical composition, as well as procedures such as sur lies maturation. Subsequent modifications involve various forms of clarification and fining, and chemical and biologic stabilization (including oxidation control). Both before and after bottling, further spontaneous chemical changes occur (aging). These affect the wine’s visual, gustatory, and olfactory attributes, with potential beneficial or detrimental consequences. These changes may occur in either inert or wood containers. Because of the significance of maturing premium wines in barrels before bottling, the taxonomy, distribution, and structural and chemical attributes of oak are noted, as well as barrel construction, conditioning, and care, as well as their alternatives. The origin and chemical and physical attributes of cork are explored, as well as stopper production, insertion, faults, and sorting, plus closure alternatives. The properties and production of various storage/transport containers (notably glass) are subsequently described. A discussion of wine spoilage follows including: cork-related problems; the various forms of microbial spoilage; sulfur and other off-odor development and control; and accidental contamination. An examination of winery waste water and treatment completes the chapter.
A new electrolyte based on fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane (F-EPE) solvent is studied in LiNi0.5Mn1.5O4/Li cells. The electrochemical stability of the electrolyte with 10% F-EPE is carried out by linear sweep voltammetry and electrochemical floating test. These results indicate that the electrolyte with F-EPE has an oxidation potential of more than 5.2 V vs. Li+/Li, which is higher than that without F-EPE and enlarges the oxidative window of electrolyte. A thin and uniform SEI layer is formed on the surface of LiNi0.5Mn1.5O4 cathode by using electrolyte with F-EPE, leads to an improvement in the electrochemical performance, validated by charge-discharge tests, EIS, SEM, TEM, and XPS analysis.
The purpose of this study was to examine specific aspects of the reliability and validity of age band 1 of the Movement Assessment Battery for Children – Second Edition (MABC-2) (Henderson, Sugden, & Barnett, 2007) in Greek preschool children. One hundred and eighty-three children participated in the study; the children ranged in age from 36 to 64 months old (M =50 months, SD=9 months). Test-retest reliability of the MABC-2 was evaluated using intraclass correlation coefficient (ICC). Cronbach's alpha for the items of each motor domain was estimated to determine internal consistency. Confirmatory factor analysis was used to examine the factorial validity of the MABC-2 test. Correlation coefficients among individual item scores and the total score were also calculated to further examine validity. The ICC for all test items was good, except for the drawing trail task, which was moderate. Cronbach's alpha coefficient values were .51, .70 and .66 for manual dexterity, aiming and catching, and balance, respectively. In the confirmatory factor analysis, goodness-of-fit indices suggested a satisfactory fit of the data to the model. The correlation coefficients between each test item and the total score were moderate. The results suggest that the MABC-2 can be a reliable and valid tool for the assessment of movement difficulties among 3–5-year-old children.
To overcome the limitation of capacity from traditional oxide-based intercalation cathodes, oxygen redox reaction garners intense interest in Li-rich/Na-rich cathodes for rechargeable batteries. However, cycle degradation and voltage drop caused by the irreversible structural changes and O2 release upon electrochemical cycling hinder their commercial applications. Herein, a Na-deficient layered compound Na0.67Mn0.72Zn0.28O2 is employed to study the relationship between the oxygen redox reaction and the (O2)n− stabilization mechanism by using a combined experimental and computational approach. Our results indicate that Na0.67Mn0.72Zn0.28O2 has a long plateau of approximately 4.1 V with a total capacity of 157 mAh g−1, majorly stemming from the oxygen redox reactions of O2−/(O2)n−. The O-2p nonbonding states originating from the weak Zn–O interaction and the shortened O–O bonds induced by the absence of Na atoms in the alkali layers catalyze the formation of peroxo-like O–O dimer between the Mn–Mn atoms. The honeycomb TM layer of the Na-deficient materials remains stable with a small O–O bond length evolution from 2.55 Å to 2.48 Å during the oxygen redox process, which stabilizes the lattice oxygen in electrochemical cycles. This finding is important for further understanding the mechanism underlying the oxygen redox chemistry of high energy Na-deficient cathode materials.