batterydata/paper-abstracts huggingface dataset:
Zinc-air batteries have a great potential to be the next generation of secondary batteries. They exhibit a high volume and mass specific power density due to the use of oxygen, which can be taken directly from air. Compared to other anodes used in rechargeable batteries, zinc offers many advantages including low cost and environmental friendliness. Unfortunately, morphological changes occur in the zinc electrode after a few charge and discharge cycles which lead to formation of needle-shaped zinc structures (dendrites). Despite many studies about suppressing dendrites by using additives in the electrolyte, no technically feasible solution could be found until today. In this contribution the influence of zinc ion concentrations in the electrolyte at the electrode surface on the dendrite formation is investigated. It is shown that dendritic zinc crystals only occur if the surface concentration of zinc ions falls below a critical value. With the knowledge of this critical surface concentration the time before growth of dendritic zinc starts can be prolonged by pulsed deposition of zinc. Moreover, dendrite growth can be completely avoided in a flow system at an appropriate flow rate in combination with a pulsed current charging procedure. With this approach the favored boulder structures were obtained with current densities up to 80 mA cm−2 and for deposition times up to 1800 s.
Layered LiNi0.5−xCaxMn0.5O2 (0 ≤ x ≤ 0.2) cathode materials were prepared through a combination of co-precipitation and a solid-state method. The prepared cathode materials were investigated in detail by X-ray diffraction (XRD), Rietveld refinement, inductively coupled plasma, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), cyclic voltammetry and charge–discharge measurements. The results of XRD, Rietveld refinement, XPS and SEM measurements revealed that Ca-doping can increase the stability of the structure and lower the amount of Li/Ni cation mixing. Furthermore, Ca-doping was not observed to affect the morphology or oxidation states of the LiNi0.5Mn0.5O2. The electrochemical measurements showed that the pristine LiNi0.5Mn0.5O2 material has the lowest discharge capacity of 88.6 mAh g−1 between 3 and 4.5 V at a constant density of 0.2 C, which was improved 38% by doping with 3 mol% of Ca. Additionally, the capacity retention of the 3 mol% Ca-doping is 20% higher than that of the pristine LiNi0.5Mn0.5O2 material in the voltage range of 3.0–4.5 V. Furthermore, we investigated the source of the enhancement of the electrochemical properties from Ca-doping. The improvement may be attributed to increased structural stability, lowered Li/Ni cation mixing, decreased polarization, reduced migration resistance and faster lithium-ion diffusion.
ZnS/C nanoparticles with core/shell structure are prepared by a simple solvothermal process followed by an annealing process. The core consists of a quite amount of ultrasmall ZnS nanocrystals (∼10nm) dispersing in in situ formed carbon matrix, which is covered by an outer carbon shell with ∼4nm thickness. The nano-sized ZnS crystals effectively shorten the lithium ion diffusion paths, while the uniform carbon shell, together with the inner amorphous carbon matrix not only provide fast electron conduction, but also act as a buffer matrix to accommodate volume change occurring on electrochemical cycling. Such hierarchical-type microstructure is beneficial concerning electrochemical performance of the proposed composite. When evaluated as an anode material for rechargeable lithium ion batteries, the ZnS/C nanocomposite shows a high specific capacity of 741mAhg−1 at a current density of 0.1Ag−1 after 300 cycles. Even at 5Ag−1, a high reversible capacity of 538mAhg−1 can be still achieved. The lithium diffusion coefficient of ZnS/C electrode is estimated as 6.1×10−11 cm2 s−1, contributing to the excellent rate performance of the material.
Both high energy density and high power density are vitally required for new applications such as electric vehicles. Here we present a comparison of two well-crystallised layered double hydroxides, [Ni4Al(OH)10]OH and [Ni4Al(OH)10]NO3, which shows that the former can maintain a better discharge capacity, 294–299mAhg−1, than the latter, 233–287mAhg−1 at a current density of 2000mAg−1 within about 300 cycles, although both electrodes deliver a similar capacity of 326mAhg−1 at 200mAg−1 initially. It is believed that both the more watery interlayer space in [Ni4Al(OH)10]OH than in [Ni4Al(OH)10]NO3 and the morphologic changes induced by anion exchange of NO3 − by OH− during electrochemical cycles play key roles in their behaviour.
NiO-V2O5 composite films have been fabricated by 355nm pulsed laser reactive deposition using mixed metallic Ni and V targets with different molar ratios. The optimal deposition conditions of NiO-V2O5 composite films are found to be the substrate temperature of 300°C and 100mTorr O2 ambient. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses showed that the crystallinity of the NiO-V2O5 composite films gradually decreased with increasing the amount of nickel oxide and transformed to amorphous phase as the molar ratio of NiO/V2O5 (x) approaches 0.5. The amorphous (NiO)0.5V2O5 composite film electrode exhibited a specific capacity of 340mAh/g at a discharge rate of 2C upon cycling with no obvious fading up to 500 cycles. XRD and X-ray photo-electron spectroscopy (XPS) measurements of NiO-V2O5 composite film electrodes revealed that there exists two electrochemical processes upon cycling. During the first discharge, the Li ions insertion process is accompanied by the reduction of NiO into metallic Ni. Then, the reversible processes involving Li ions insertion/extraction in V2O5 matrix and oxidation/reduction of Ni and Li2O take place upon the subsequent cycling.
The effect of retirement on life satisfaction is a research topic that received a lot of attention, yet provided heterogeneous results. The current study suggests a remedy for this situation by taking two predictors of diversity (i.e. education and last labor market status) into account. We assumed that changes in social status and changes in resources influence retirement adjustment. The social status change affects retirees in the short-term, whereas individuals’ resources indicated by education predict long-term adjustment. To disentangle these processes, we contrasted exits from full-time employment and transitions from unemployment. We used data from the German Socio-Economic Panel to estimate a multi-group, multi-episodes dual change score model. The development of life satisfaction is lastingly interrupted by retirement. A short-term increase in life satisfaction was found for both transition groups but was more pronounced for those being previously unemployed. Life satisfaction develops in the long-term education-specific: retirees who have more education show almost constant life satisfaction whereas those retirees who have less education experience a decline. The results indicate that retirement entails a major change in the way people live. Adjustment to this can be characterized by two processes: A status change enfolds in the short-term. A building of new daily routines using individuals’ resources develops in the long-term. Both processes can be interpreted in terms of cumulative inequality: last labor market status differences decrease in the short-term but remain. Educational differences increase after retirement.
We designed and implemented an edutainment platform, Dreamware. It effectively helps education, sensibility treatment and intelligence training for children with developmental disability. We developed special toy-like hardware and software tools: a content authoring tool that makes a variety of multimedia content operating on the hardware, a management tool that provides training results to instructors, and a real-time monitoring tool to observe the current state of learning. The hardware is designed to consider the characteristics of children with developmental disability. It can provide sensibility training, such as visual, auditory, and tactile senses to them. The easy-to-use authoring tool enables teachers and non-specialists to make educational content conveniently. In addition, the real-time monitoring tool helps observe the user’s status, even outside the classroom. The management tool stores training results and provides the result for further steps. Efficient repetitive training is possible without restriction of time and location using this platform. We can recognize that our system is effective in improving their concentration and learning.
Future pervasive computing applications are envisioned to adapt the applications’ behaviors by utilizing various contexts of an environment and its users. Such context information may often be ambiguous and also heterogeneous, which make the delivery of unambiguous context information to real applications extremely challenging. Thus, a significant challenge facing the development of realistic and deployable context-aware services for pervasive computing applications is the ability to deal with these ambiguous contexts. In this paper, we propose a resource optimized quality assured context mediation framework based on efficient context-aware data fusion and semantic-based context delivery. In this framework, contexts are first fused by an active fusion technique based on Dynamic Bayesian Networks and ontology, and further mediated using a composable ontological rule-based model with the involvement of users or application developers. The fused context data are then organized into an ontology-based semantic network together with the associated ontologies in order to facilitate efficient context delivery. Experimental results using SunSPOT and other sensors demonstrate the promise of this approach.
Chemical lithiation of amorphous FePO4 with LiI in acetonitrile is performed to form amorphous LiFePO4. The amorphous FePO4·2H2O precursor is synthesized by co-precipitation method from equimolar aqueous solutions of FeSO4·7H2O and NH4H2PO4, using H2O2 (hydrogen peroxide) as the oxidizing agent. The nanocrystalline LiFePO4/C is obtained by annealing the amorphous LiFePO4 and in situ carbon coating with sucrose in a reducing atmosphere. The particle size of FePO4·2H2O precursor decreases with increasing reaction temperature. The final LiFePO4/C products completely maintain the shape and size of the precursor even after annealing at 700 °C for 2 h. The excellent electrochemical properties of these nanocrystalline LiFePO4/C composites suggest that to decrease the particle size of LiFePO4 is very effective in enhancing the rate capability and cycle performance. The specific discharge capacities of LiFePO4/C obtained from the FePO4·2H2O precursor synthesized at 75 °C are 151.8 and 133.5 mAh g−1 at 0.1 and 1 C rates, with a low capacity fading of about 0.075 % per cycle over 50 cycles at 0.5 C rate.
Current psychopharmacological approaches to reduce psychotic phenomenology in schizophrenia are associated with adverse effects including extrapyramidal and metabolic side effects. In view of the emerging data on nutritional supplementation interventions in schizophrenia which are not entirely consistent, we aimed to review existent studies focusing on fatty acid and vitamin interventions and summarise current evidence on such nutritional supplementations in schizophrenia. We searched the digital databases (ScienceDirect, Scopus, SpringerLINK, PubMed/Medline) for relevant studies pertaining to fatty acid and vitamin supplementation interventions in the management of psychotic symptoms in schizophrenia up to February 2015. Overall, there were more studies conducted on fatty acid over vitamin supplementations in patients with schizophrenia. There were more positive findings in support of fatty acid supplementation compared with vitamin supplementation in the context of specific intervention features (dose of nutrient supplementation, single versus combination nutritional interventions, specific antipsychotic), subject features (older age, long duration of illness, baseline polyunsaturated fatty acid levels) and clinical outcomes (improvements of psychotic symptoms and/or extrapyramidal side effects from antipsychotics). However, investigations of both supplementation modalities were limited by relatively small study sample sizes, short study duration, which precluded further segmentation of impact on more diverse patient subtypes and symptom profiles. Future studies may consider examining larger samples over a longer time period, recruiting younger subjects with shorter duration of illness, examination of different clinical features including specific cognitive domains, and use of single versus combination nutritional interventions.
The electrochemical behavior of lithium in lithium hydroxide solution with sodium nitrite has been investigated in this paper. The results show that the hydrogen evolution rate decreases with increasing sodium nitrite concentration. Through potentiostatic polarization and scanning electron microscope (SEM), we found that the current efficiency keeps nearly unchanged with sodium nitrite introduction to the solutions. The porosity of the lithium surface film decreased due to the precipitation of LiOH promoted by sodium nitrite.
Thirteen children and young adults with Down syndrome (DS) completed tests of language and reading and their performance was compared to that of three control groups. Reading comprehension was confirmed to be a specific deficit in DS and found to be strongly correlated with underlying language skills. Although reading comprehension was more strongly related to language ability in the DS group, this was shown to be a function of more advanced word recognition rather than a characteristic of DS per se. Individuals with DS were found to have greater difficulty with inferential comprehension questions than expected given their overall comprehension ability and the reading profile associated with DS was found to be similar to that of children known as poor comprehenders. It is recommended that oral language training programs, similar to those that have been shown to improve reading comprehension in poor comprehenders, be trialed with children who have DS.
The phase transition of carbonate solvent mixture solutions consisting of ethylene carbonate (EC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and LiPF6 salt have been studied for improving the low temperature performance of lithium-ion batteries. The Li ion conductivity at 25 °C was maximum at x = 0.3 in a series of 1 M LiPF6 mixed carbonate solvents compositions consisting of ECxDMC0.5−0.5xEMC0.5−0.5x (x = 0 to 0.6), while the maximum tended to shift to x = 0.2 as the temperature lowered. The differential scanning calorimetry results showed that the freezing temperature depressions of EC in the 1 M LiPF6 solution were larger than those of the DMC or EMC. The chemical shift of 7Li nuclear magnetic resonance changed from a constant to increasing at around x = 0.3, which could be reasonably understood by focusing on the change in solvation energy calculated using Born equation. However, in the region of a high EC concentration of over x = 0.3 (EC/LiPF6 > 4) in the 1 M LiPF6 solution, the free EC from the solvation to the lithium ions seems to reduce the freezing temperature depression of the EC, and thus, decreases the ionic conductivity of the solution at low temperatures, due to the EC freezing.
Inverse spinel structure Zn2SnO4 was successfully synthesized by a simple hydrothermal process using NaOH as an alkaline mineralizer. The hydrothermal conditions, such as alkaline concentration and synthesis temperature, have an important influence on the structure and performance of the product. The structural, morphological and electrochemical properties were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical measurement. The electrochemical test showed that Zn2SnO4, which was prepared at 0.2M NaOH concentration at 220°C for 24h, showed 1903.6mAh/g of initial discharge capacity and 1045.5mAh/g of initial charge capacity. A specific discharge capacity of 644.7mAh/g remained after 20 cycles.
The purpose of this study was to compare the neuropsychological profile of women with VEEG-confirmed diagnoses of psychogenic nonepileptic seizures (PNES) with that of an age- and education-matched group of women with left temporal lobe epilepsy (LTLE). Results indicate that in a relatively homogenous PNES sample, no severe neurocognitive impairments were present, further supporting a psychologically versus neurologically driven pathology of PNES. In comparison to age-stratified normative data, the PNES group demonstrated only a modest deficiency across neuropsychological domains and a relative area of weakness in attention and working memory, and generally outperformed their counterparts with LTLE. Although the attentional deficits in the PNES group may have been influenced by their elevated levels of emotional distress, symptoms of depression and anxiety were significant and common in both patients with PNES and those with LTLE, and therefore, the utility of psychological factors in discriminating these groups is limited. The present findings warrant the use of longitudinal research with patients with PNES to identify changes in the presentation of this condition as well as its subsequent neurocognitive and emotional impairments.
This paper investigates the business case of power storage attached to PV generation from the perspective of an aggregator trading power on wholesale markets and possibly supplying household customers. The profitability and an optimum storage configuration are determined for two European regions: Baden-Wuerttemberg in Germany and Puglia in Italy based on wholesale price data and solar irradiation data for the years 2007–2011. During this period of time and under the assumptions made, adding storage to a portfolio of PV generators would not have constituted a business case for Baden-Wuerttemberg while profitability could have been reached for Puglia. However, the return of PV-attached storage that could have been achieved in Puglia during the years 2007–2011 is below levels typically required by companies operating on wholesale markets (deregulated power generators or traders) as those market participants’ capital costs are usually significantly higher than borrowing costs of the state. Storage proved to be financially more attractive in cases where severe grid constraints lead to significant levels of curtailment provided that the associated losses would not be financially compensated. This could pose a risk to any investor as grid upgrades would eventually erode the revenues. Restricting the storage to PV energy only (i.e. without the possibility to do arbitrage on markets) depresses the business case and is generally unprofitable, except but for situations of severe grid bottlenecks. The picture does not change significantly if a consumption portfolio is added. In order to reach profitability, the energy related CAPEX will have to fall to a range of 100–150€/kWh. The optimal storage configuration depends on its usage and does not exceed 5h of discharge at full power with the discharging power limited to 40% of the nominal PV capacity.
Si nanocrystallites embedded in Cu-Al-Fe matrix were developed using arc melting followed by a rapid quenching method which could produce a large scale at one time. Si nanocrystallites of approximately 100nm were dispersed in matrix composed of Al4Cu9 and AlFe phases. To identify the reaction mechanism, the ex situ XRD and HRTEM analyses were employed. Only Si reacted with Li forming a Li15Si4 phase as the final product while the Al4Cu9 and AlFe phases acted as inactive matrix during the first discharge. The Si/Cu-Al-Fe composite showed a good cycle performance with 836 mAh g−1 over 50 cycles. This indicated that inactive matrices not only endured the stress caused by volume expansion of Li-Si alloy but also provided a good electron path as a conductor.
The social network centrality of Chief Executive Officers (CEOs) has received tremendous attention in recent research. This study examines how CEO network centrality relates to corporate cash holdings. We find a significant negative relation between CEO network centrality and the level of corporate cash holdings, suggesting that firms with higher-centrality CEOs hold less cash. Our results still hold after a battery of robustness checks.
Although studying the effects of diet on cognitive function in children is of great interest to nutritionists, many have not received the formal training in the principles and practice of assessment necessary to properly evaluate research studies or to design and conduct research themselves. This paper is aimed at such an audience and assumes little prior knowledge of the field. A short description of neural development in childhood is followed by a discussion of important principles of assessment. A level of assessment approach is used to present a selection of widely used cognitive tests organized by cognitive domain and age group. Practical information about the tests is presented in tabular form and a list of useful websites is included.
There is a need for a validated short instrument that can be used in routine practice to quantify potential short-term change in Health-Related Quality of Life (HRQoL) in patients with chronic obstructive pulmonary disease (COPD). Our aim is to determine the validity and reliability of the VQ11 questionnaire dedicated to the routine assessment of HRQoL.
The present study investigated associations between maternal relationship instability patterns and children’s behavioral and emotional functioning in middle childhood in a representative sample of low-income urban families (N = 891). Data from the Three-City Study tracked maternal partnerships through the child’s life, assessing total marital and cohabiting relationship transitions and delineating transitions by developmental timing, and by directionality (i.e., entrances into versus exits from partnerships). Analyses linking instability to child behaviors at age 8 found that a greater total number of maternal relationship transitions predicted higher anxious, somatic, and conduct problems, with recent transitions (in the prior 2 years) driving these results. Consideration of partnership formations versus dissolutions indicated that recent entrances into new partnerships, and entrances into cohabitations, were most consistently associated with problematic functioning across numerous aspects of children’s emotional and behavioral functioning. Policy implications of these findings are discussed.
Adverse childhood experiences (ACEs) are known risk factors for obesity and poor outcomes following weight loss interventions. ACEs are also associated with addictive behaviors and, potentially, food addiction (FA). This study examined the relationship between ACEs and FA, and their association to undergoing bariatric surgery and post-surgical weight loss outcomes.