batterydata/paper-abstracts huggingface dataset:
Experimental thermophysical property data for composites of electrode and electrolyte materials are needed in order to provide better bases to model and/or design high thermal conductivity Li-ion cells. In this study, we have determined thermal conductivity (k) values for negative electrode (NE) materials made of synthetic graphite of various particle sizes, with varying polyvinylidene difluoride (PVDF) binder and carbon-black (C-Black) contents, using various levels of compression pressure. Experiments were conducted at room temperature (RT), 150 and 200°C. Requirements for designing a high thermal conductivity NE-material are suggested. Detailed statistical data analysis shows that the thermal conductivity of the NE-material most strongly depends on compression pressure, followed by graphite particle size, C-Black content and finally PVDF content. The maximum k-value was achieved for the samples made of the largest graphite particles (75μm), the smallest C-Black content (5wt.%) and the highest compression pressure (566kgcm−2). Increasing the PVDF content from 10 to 15wt.% increased the k-values by 11–13% only. The k-values of all samples decreased with increasing temperature; at 200°C, the k-values were close to each other irrespective of preparation procedure and/or raw material contents. This most likely is due to the relaxation of contact pressure among the graphite particles because of PVDF melting at 155–160°C.
Introduction Subjects with a psychotic disorder show mild to moderate cognitive impairment, which is an important determinant of functional outcome. The underlying biological process of cognitive impairment in psychosis is unclear. We aimed to explore whether hypothalamic–pituitary–thyroid axis hormones or thyroid autoimmunity modulate cognitive functioning in subjects with early psychosis. Methods We studied 70 patients with a psychotic disorder (<3years of illness) and a control group of 37 healthy subjects (HS). Plasma levels of thyroid-stimulating hormone (TSH), free thyroxine (FT4) and thyroid-peroxidase (TPO-Abs) and thyroglobulin antibodies (TG-Abs) were determined. Cognitive assessment was performed with the MATRICS Cognitive Consensus Cognitive Battery. We also explored the relationship between thyroid variables and cognition in three subgroups of psychotic patients: psychosis not otherwise specified, affective psychosis (bipolar disorder or schizoaffective disorder) and non-affective psychosis (schizophrenia or schizophreniphorm disorder). Results In patients with early psychosis, higher FT4 levels (but not TSH or thyroid antibodies) were associated with better cognitive performance in attention/vigilance and overall cognition. The relationship between FT4 levels and the attention/vigilance domain remained significant in a multivariate analysis after adjusting for education level, age, gender, substance use, and benzodiazepine and antipsychotic treatments. We did not find a significant association between FT4 and cognitive performance in HS. In the exploratory analysis by psychotic subtypes, subjects with affective psychosis had increased FT4 levels and better cognitive profile than those with non-affective psychosis. Conclusions Our study suggests that FT4 levels are associated with cognitive abilities (attention/vigilance and overall cognition) in individuals with early psychosis.
The effect of heptamethyldisilazane as additive on the stability of the electrolyte and cycling performance of LiMn2O4 batteries was studied by linear sweep voltammetry, charge–discharge of battery, stability measurement and high temperature test. The results show that the addition of heptamethyldisilazane to the electrolyte can suppress the contents of HF in the electrolyte and the cycling performance of LiMn2O4 batteries can be improved. After storage at 60°C for 7 days, the stability of batteries using electrolyte with heptamethyldisilazane can be improved, however the stability of batteries using the electrolyte with heptamethyldisilazane can be weakened after storage at 85°C for 4h.
Lithium-rich layered oxide, Li[Li0.131Ni0.304Mn0.565]O2 with uniform particle size, is prepared through co-precipitation of metal hydroxide with synergistic dispersion of polyvinylpyrrolidone and ethylene glycol and subsequent solid reaction with lithium hydroxide. The crystal structure and morphology of the prepared sample is characterized with X-ray diffraction and scanning electron microscope. It is found that the prepared sample is a solid solution of Li2MnO3 and LiNi0.5Mn0.5O2, with uniform particle size of about 230 nm. Charge/discharge tests indicate that the prepared sample exhibits improved elevated-temperature discharge capacity and cycling stability. In the region of 3.0–4.8 V, the prepared sample delivers initially a 0.1 C (1 C = 263 mAh g−1) capacity of 256 mAh g−1 at 50 °C and 205 mAh g−1 at 25 °C, and the 0.1 C capacity at 25 °C retains 178 mAh g−1 after 60 cycles. The capacity decay mechanism is understood in detail through dQ/dV analyses.
A new kind of membrane free liquid metal battery was developed. The battery employs liquid sodium and zinc as electrodes both in liquid state, and NaCl-CaCl2 molten salts as electrolyte. The discharge flat voltage is in the range of about 1.4 V–1.8 V, and the cycle efficiency achieved is about 90% at low discharge current densities (below 40 mA cm−2). Moreover, this battery can also be charged and discharged at high current density with good performance. The discharge flat voltage is above 1.1 V when it is discharged at 100 mA cm−2, while it is about 0.8 V with 100% cycle efficiency when it is discharged at 200 mA cm−2. Compared to other reported liquid metal battery, this battery has lower cost, which suggests broad application prospect in energy storage systems for power grid.
An increase beyond 70% in specific energy of an asymmetrical supercapacitor of carbon (−) and composite of carbon nanotubes and polyaniline (+) was achieved by firstly identifying the ‘cell voltage limiting electrode’, and then adjusting the capacitance ratio of the ±electrodes from 1.0 to 1.3.
The compatibility between dimethyl methylphosphonate (DMMP)-based electrolyte of 1M LiPF6/EC+DMC+DMMP (1:1:2wt.) and spinel materials Li4Ti5O12 and LiNi0.5Mn1.5O4 was reviewed, respectively. The cell performance and impedance of 3-V LiNi0.5Mn1.5O4/Li4Ti5O12 lithium-ion cell with the DMMP-based nonflammable electrolyte was compared with the baseline electrolyte of 1M LiPF6/EC+DMC (1:1wt.). The nonflammable DMMP-based electrolyte exhibited good compatibility with spinel Li4Ti5O12 anode and high-voltage LiNi0.5Mn1.5O4 cathode, and acceptable cycling performance in the LiNi0.5Mn1.5O4/Li4Ti5O12 full-cell, except for the higher impedance than that in the baseline electrolyte. All of the results disclosed that the 3V LiNi0.5Mn1.5O4/Li4Ti5O12 lithium-ion battery was a promising choice for the nonflammable DMMP-based electrolyte.
A novel ultrasonic velocity sensing approach is proposed and investigated to monitor the state of charge (SOC) of a vanadium redox flow battery (VRB, or VRFB). The positive electrode is designated as the energy storage capacity-limiting one so that the molar ratio of the V5+ ion in the positive electrolyte solution determines the SOC of a VRB. The tested single-cell VRB is connected to an ultrasonic sensor and charged/discharged almost to its two extremes at a constant current of 2A under various operating temperatures. It is found that the ultrasound velocity exhibits distinct variations in accordance with changes of vanadium ion compositions in the positive electrolyte solution as the SOC of the VRB varies. The SOC obtained can be depicted in a 3D plot in terms of ultrasound velocity and operating temperature. An empirical model equation is proposed and found to fit the experimental results of both charging and discharging stages quite well. The advantages of this SOC sensing approach are that it is totally independent of VRB operations and can be readily applied to both sides of the electrodes. It is expected to develop into a dependable method for accurate and real-time monitoring of SOC for VRB.
Amusia (commonly referred to as tone-deafness) is a difficulty in discriminating pitch changes in melodies that affects around 4% of the human population. Amusia cannot be explained as a simple sensory impairment. Here we show that amusia is strongly related to a deficit in spatial processing in adults. Compared to two matched control groups (musicians and non-musicians), participants in the amusic group were significantly impaired on a visually presented mental rotation task. Amusic subjects were also less prone to interference in a spatial stimulus-response incompatibility task and performed significantly faster than controls in an interference task in which they were required to make simple pitch discriminations while concurrently performing a mental rotation task. This indicates that the processing of pitch in music normally depends on the cognitive mechanisms that are used to process spatial representations in other modalities.
The spinel LiMn2O4 was recognized as an appealing candidate cathode material for high rate Li-ion battery, but it suffers from severe capacity fading, especially at a high temperature. In order to solve this problem, we prepared V2O5 coated LiMn2O4 (LiMn2O4@V2O5) samples in this work and its structure and morphology were characterized by powder X-ray diffraction, scanning electron microscope, and transmission electron microscope. The LiMn2O4@V2O5 material delivers an excellent cycling ability and rate capability in lithium batteries, while sustaining a capacity of 75.5 mAh g−1 after 200 cycles at 2C with a high operating temperature (328K). This performance are much better than that of LiMn2O4 (35.4 mAh g−1) without V2O5 coating, the capacity of which faded seriously. These results indicated that the surface modification of V2O5, which possess a relative lower operating potential (≤ 3.7V, LixV2-x/5O5) compare to the LiMn2O4 (∼ 3.9 and 4.1V), can improve the electrochemical properties of LiMn2O4 by endowing a fast lithium diffusion and reasonable electronic conductivity which facilitates the transformation of the electrons and ions. In addition, the acidic and isolated protective layer of V2O5 can work as a HF inhibitor and/or HF scavenger and suppress the dissolution of manganese into electrolyte. Thus, we believe that such a LiMn2O4@V2O5 composite can be an economical and viable candidate cathode material for Li-ion batteries.
A Correction to this paper has been published: https://doi.org/10.1038/s41560-021-00845-2.
The combination of high spatial resolution and near-surface chemical information makes Auger electron spectroscopy (AES) a powerful tool for comprehensive surface analysis. The recent interest in lithium metal as an active material in lithium sulphur or lithium air batteries increases the demand for a thorough knowledge of the reactions happening at the electrode interface. Applying AES to the complex surfaces of batteries, however, requires a detailed understanding of the interactions occurring with the highly reactive materials during investigation, especially when using metallic lithium with its passivation layers formed even under glove box atmosphere. The article is focused on the influence of electron beam damage and residual gas under ultra-high vacuum conditions on the observations made. Immediate irradiation effects are shown to highly depend on electron dose leading to misinterpretation the surface composition and a non-sufficient stability of the sample. The results are further supported by coupled X-ray photoelectron spectroscopy (XPS) measurements that help to understand the beam induced phenomena. An improved output of the spectroscopic measurement could be achieved employing AES mappings. This allows an improved insight into the local distribution of different lithium compounds in the material surface and can also be applied to other battery active materials.
Blend membranes of sulfonated poly(ether ether ketone) (SPEEK) and poly(vinylidene fluoride) (PVdF) are prepared with various mixing mass ratios for vanadium redox flow battery application for the first time. The SPEEK/PVdF blend membranes are characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. The water uptake, swelling ratio, ion exchange capacity, proton conductivity, VO2+ permeability, ion selectivity, single cell performance and mechanical property of blend membranes are detailed evaluated. The blend membranes are dense and uniform when PVdF mass ratio ranges from 5 wt.% to 20 wt.%. The blend membrane with 15 wt.% PVdF (denoted as S/P 15) is further investigated for its good balance of proton conductivity and ion selectivity. The cell with S/P 15 membrane shows higher coulombic efficiency and energy efficiency compared with Nafion 117 membrane (98.0% vs. 92.0% and 81.0% vs. 75.8%, respectively). Furthermore, no obvious efficiency declines are observed after 80 cycles cell test accompanied with a lower discharge capacity decay rate.
The electrochemical activity of TiNiSn, TiNi 2Sn and Ti 6Sn 5 compounds considered as negative electrode materials for Li-ion batteries has been predicted from the isomer shift- Hume-Rothery electronic density correlation diagram. The ternary compounds were obtained from solid-state reactions and Ti 6Sn 5 by ball milling. The 119Sn Mössbauer parameters were experimentally determined and used to evaluate the Hume-Rothery electronic density [e av]. The values of [e av] are in the region of Li-rich Li-Sn alloys for Ti 6Sn 5 and outside this region for the ternary compounds, suggesting that the former compound is electrochemically active but not the two latter ones. Electrochemical tests were performed for these different materials confirming this prediction. The close values of [e av] for Ti 6Sn 5 and Li-rich Li-Sn alloys indicate that the observed good capacity retention could be related to small changes in the global structures during cycling.
The 4th Schizophrenia International Research Society Conference was held in Florence, Italy, April 5–9, 2014 and this year had as its emphasis, “Fostering Collaboration in Schizophrenia Research”. Student travel awardees served as rapporteurs for each oral session, summarized the important contributions of each session and then each report was integrated into a final summary of data discussed at the entire conference by topic. It is hoped that by combining data from different presentations, patterns of interest will emerge and thus lead to new progress for the future. In addition, the following report provides an overview of the conference for those who were present, but could not participate in all sessions, and those who did not have the opportunity to attend, but who would be interested in an update on current investigations ongoing in the field of schizophrenia research.
is Automotive Project Manager in the Battery Case Program at SGL Carbon in Meitingen (Germany).
Social rank determines access to feeding and breeding opportunities. Stagkourakis et al. identify an intrinsically amplifying hypothalamic circuit that can generate intermale attack and aggression reward to influence hierarchical status among males.
The oil-dependent electricity generation situation met in the Aegean Archipelago Islands is in great deal determined by increased rates of fuel consumption and analogous electricity production costs, this being also the case for other island autonomous electrical networks worldwide. Meanwhile, the contribution of renewable energy sources (RES) to the constant increase recorded in both the Aegean islands’ annual electricity generation and the corresponding peak load demand is very limited. To compensate the unfavorable situation encountered, the implementation of energy storage systems (ESS) that can both utilize the excess/rejected energy produced from RES plants and improve the operation of existing thermal power units is recommended. In the present study, a techno-economic comparison of various RES-ESS configurations supported by the supplementary or back-up use of existing thermal units is undertaken. From the results obtained, the shift of direction from the existing oil-dependent status to a RES-based alternative in collaboration with certain storage technologies entails – apart from the clear environmental benefits – financial advantages as well.
A crucial component of language is represented by the prosodic system because it provides essential elements to speaker about how a sentence should be interpreted or intended (Fodor, 2002). Increasing interest from researchers also relates to the understanding of figurative language (Levorato, & Cacciari, 2002). In the figures of speech that the speaker wants the listener intends something more or different than what is explicitly stated (Glucksberg, 2001). In particular, prosodic intonation is crucial in the resolution of syntactic ambiguity and structural features that constitute the complex messages, such as idioms and proverbs. A crucial component of language, therefore, is represented by the prosodic system because it provides essential elements to talking about how a sentence should be interpreted or understood. The ability to relate to metalinguistic understanding the cognitive processes that allow you to reflect on language and manipulate its characteristics. These capabilities are essential to recognize and resolve the ambiguities of a complex message, you can control and plan the way we produce and understand language (Levorato, 2007). The study demonstrates that an understanding prosodic correlates with the understanding of idioms and proverbs, which are crucial for the achievement of metalinguistic awareness, are influenced by the level of schooling and socio-cultural.
In this paper, the development of a new prognostic estimation technique for on-line gear health management system is described and demonstrated with real spiral bevel gear run-to-failure test data. Unlike conventional particle filter-based prognostic estimation methods, the prognostic technique presented in this paper is a hybrid of the unscented Kalman filter and particle filter. It is designed to improve the processing efficiency whilst the state estimation accuracy is maintained. The unscented Kalman filter is utilized to obtain the “best estimate” of the states of a degrading nonlinear component and the particle filter l-step ahead prediction technique is employed to obtain the remaining useful life of the component. In addition, data mining techniques are applied to efficiently define the system dynamics model, observation model, and predicted measurement information for the prognostic estimator. At last, the feasibility of the presented prognostic estimator is demonstrated with satisfactory results using the actual oil debris mass and health index data obtained from a spiral bevel gear test rig.
The impedance behaviors of Si–O–C composite film electrodeposited on Cu microcones-arrayed current collector have been investigated to understand the electrochemical process kinetics that influences the cycling performance when used as a highly-durable anode in a lithium battery. The impedance was measured by using impedance spectroscopy in equilibrium conditions at various depths of discharge and during several hundred charge–discharge cycles. The measured impedance was interpreted with an equivalent circuit composed of solid electrolyte interphase (SEI) film, charge transfer and solid state diffusion. The impedance analysis shows that the change of charge transfer resistance is the main contribution to the total resistance change during discharge, but an abrupt augmentation of diffusive resistance at high depth of discharge is also observed which cannot be explained very well by the presented model. The impedance evolution of this electrode during charge–discharge cycles suggests that the slow growth of the SEI film as well as the increase of the electrode density are responsible for the capacity fading after long term cycling.
Tunable LiFePO4/C thin films demonstrating high power were fabricated by drop-casting a LiFePO4 nano-plate/sucrose suspension on titanium foil, followed by pyrolysis at 600°C for 3h in nitrogen. The thickness, carbon content, and morphology of the LiFePO4/C film cathode can be adjusted by changing the amount of drop-cast, sucrose solution concentration and LiFePO4 raw material. For this work, well-crystallized LiFePO4 nano-plates synthesized via solvothermal route were used to prepare high power LiFePO4/C thin films. The resultant binder-free films consisted of well-packed LiFePO4 nano-plates coated with nano-carbon, a result of sucrose pyrolysis, and were directly assembled into cells for testing. The LiFePO4/C nano-composite film cathode delivered a lithium ion intercalation capacity of 162mAhg−1 and 90mAhg−1 at current density of 170mAg−1 (1C) and 1.7Ag−1 (10C), respectively, while demonstrating excellent cyclic stability.
A device has been designed to generate hydrogen for a fuel cell powered cellular phone. The device is based on the chemical reaction between NaBH4 and hydrochloric/water solution to satisfy the hydrogen request at room temperature and pressure. The operation mechanism and controlling method is based on the Kipp's gas generating apparatus. A prototype has been built and tested to evaluate the optimum salt/acid and acid/solution ratios and check the hydrogen mass flow rates upon operation and the pressure variation in stand-by condition. The system works delivering hydrogen flows ranging between 0 and 10mlmin−1. In a typical test the hydrogen flow was set to 5mlmin−1 to match a 1W power fuel cell. The working pressure was slightly higher than the atmospheric one. The hydrogen capacity was as high as 2.5%(w/w). By converting this amount of hydrogen in electricity by a fuel cell working at 0.8V it is possible to achieve a system energy density of about 720Whkg−1, four times larger than commercial high energy density lithium-ion batteries.
Executive dysfunction is frequently reported in Alzheimer's disease (AD) and the frontal variant of frontotemporal dementia (FTD). More specifically, inhibitory dysfunction is observed early in AD and inhibitory deficits are also prominent in patients with FTD. However, few studies have simultaneously explored and compared inhibitory abilities in both degenerative diseases. Consequently, the aim of this study was to compare verbal and motor inhibitory processes in the initial stages of AD and the frontal variant of FTD. Stroop and Go/No-go tasks were administered. The results demonstrate that, on the Go/No-go task, AD and FTD patients do not produce more errors than control subjects. However, both groups are impaired on the Stroop task (mainly with regard to the error score) but do not differ from each other. These results indicate that AD and FTD patients do not present a general impairment of their inhibitory abilities. Moreover, these two kinds of dementia present similar quantitative and qualitative inhibitory impairments on the two tasks, although their patterns of structural and functional cerebral impairments are known to be different. The presence of similar inhibitory deficits despite very different patterns of brain damage is in agreement with the hypothesis that inhibitory dysfunction in the two groups of patients depends on a disconnection process between anterior and posterior cerebral areas, rather than on the presence of focal metabolism decreases in different regions.