batterydata/paper-abstracts huggingface dataset:
Hydrolysis of organic titanate was used to modify γ-MnO2 to produce a TiO2/MnOx composite as a new anode material with enhanced electrochemical properties for lithium ion battery. The composition, structure, valence state as well as the lithium storage mechanism of the composite have been carefully studied with inductively coupled plasma (ICP) elemental analysis, X-ray diffraction(XRD), electron microscopy, X-ray photoelectron spectroscopy (XPS) and solid-state nuclear magnetic resonance (NMR) spectroscopy. The electrochemical measurement shows that the specific capacity of the composite stays above 972mAh/g for 100 cycles at a current rate of 100mA/g, which is much better than γ-MnO2. The significant improvement can be ascribed to the involvement of both insertion and conversion lithium storage mechanisms owing to the incorporation of a small amount of TiO2 (∼5%) to MnO2, as well as the presence of Mn2O3 in the composite. This new strategy is expected to be extended to improve the electrochemical properties of other metal oxides for lithium ion battery applications.
All-solid-state sodium batteries are attractive due to the abundance of sodium and advantageous for safe battery operation by avoiding flammable organics and liquids and suppressed dendrite formation. Currently, the lack of a chemically stable sodium solid electrolyte with high ion conductivity at room temperature is one of the challenges for future development of sodium batteries. Herein, we present a NaxCoO2/Nasicon/Na thin-film model sodium solid-state battery using a Sc-substituted Nasicon solid electrolyte with a high ionic conductivity of 4 × 10−3 S cm−1. The battery shows a high specific capacity of 150 mAh g−1 at room-temperature and discharge rates of up to 6C. Excellent chemical stability of this solid electrolyte at high voltages of up to 4.2 V increases the accessible sodium (de)intercalation range and battery capacity. Direct extraction of the interface resistances between the electrode materials of the thin-film model cell using electrochemical impedance spectroscopy gives a unique opportunity of correlation the electrochemical performance with properties of electrode materials and their interfaces.
The synthesis of solid electrolytes with high ionic conductivity and the design of electrode interface with preferable compatibility are critical to realize the bulk-type application of all-solid-state batteries. In order to realize the superior electrochemical performance, argyrodite Li6PS5Cl is a promising solid electrolyte in all-solid-state batteries due to high ionic conductivity and electrochemical stability. Meanwhile, the solution reprecipitation is a valid process providing intimate ionic contact between electrodes and electrolytes to mitigate the interface incompatibility. Here, a wet-slurry process by dispersing active material (LiNi0.8Co0.1Mn0.1O2), solid electrolyte (Li6PS5Cl), binder (ethyl cellulose) and conductive additives (carbon black) in anhydrous ethanol is developed to fabricate cathode. The effect of different contents of the binder in the composite cathodes on the electrochemical performance is investigated. The all-solid-state battery with a composite cathode containing 1 wt% of ethyl cellulose shows a reversible discharge capacity of 111.7 mAh g−1 at 30 °C and its capacity retention is approximately 89.7% after 100 cycles. This work demonstrates that the fast ion migration and stable interface between active particles and solid electrolyte enabled by optimum content of chemically compatible binder are critical to the electrochemical performance of all-solid-state lithium-ion batteries.
Patient participation is important for improving outcomes, respect for self-determination and legal aspects in care. However, how patients with heart failure view participation and which factors may be associated with participation is not known. The aim of this study was therefore to describe the influence of structured home care on patient participation over time in patients diagnosed with heart failure, and to explore factors associated with participation in care.
The main aims in the care of individuals with amyotrophic lateral sclerosis (ALS) are to minimize morbidity and maximize quality of life. Although no cure exists for ALS, supportive and symptomatic care provided by a specialist multidisciplinary team can improve survival. The basis for supportive management is shifting from expert consensus guidelines towards an evidence-based approach, which encourages the use of effective treatments and could reduce the risk of harm caused by ineffective or unsafe interventions. For example, respiratory support using noninvasive ventilation has been demonstrated to improve survival and quality of life, whereas evidence supporting other respiratory interventions is insufficient. Increasing evidence implicates a causal role for metabolic dysfunction in ALS, suggesting that optimizing nutrition could improve quality of life and survival. The high incidence of cognitive dysfunction and its impact on prognosis is increasingly recognized, although evidence for effective treatments is lacking. A variety of strategies are used to manage the other physical and psychological symptoms, the majority of which have yet to be thoroughly evaluated. The need for specialist palliative care throughout the disease is increasingly recognized. This Review describes the current approaches to symptomatic and supportive care in ALS and outlines the current guidance and evidence for these strategies.
Seizure-prone EL/Suz mice have been studied as a model of multifactorial epilepsy for five decades. In prior behavioral studies, EL/Suz mice were shown to exhibit heightened locomotor activity, which implies a state of underlying hyperexcitability. The aim of the present study was to establish the premorbid behavioral development of basic motor skills and activity levels of EL/Suz mice, as compared with DDY mice, the control strain that is not seizure-prone. EL/Suz and DDY pups were monitored from Postnatal Day (PND) 3 to assess body weight, surface righting, negative geotaxis, forelimb grip strength, eye opening, habituation to a novel environment, and exploratory behavior in a two-compartment task. EL/Suz mice weighed less from PNDs 3 to 21 and exhibited delayed surface righting (PNDs 3, 5, 7) and negative geotaxis (PNDs 5, 7, 9) responses. EL/Suz and DDY mice differed in their habituation to a novel environment, with EL/Suz mice exhibiting higher activity, both within a single 10-minute session and across the 3 days of testing. EL/Suz and DDY mice also differed in the two-compartment task, with EL/Suz mice exhibiting increased locomotor activity and spending a greater amount of time in the light compartment. Thus, the present findings reveal that EL/Suz mice exhibit some developmental delays, altered habituation to a novel environment, and increased exploratory activity. Overall, the present results demonstrate that the behavioral and physiological phenotype of seizure-prone EL/Suz mice is deviant more than 2 months before the onset of seizure susceptibility.
Twenty four waste cellular phones, manufactured between 2002 and 2011, were selected in order to determine the total heavy metal content in each of their parts (printed circuit boards (PCBs), plastic housing (PH) and liquid crystal display monitors (LCDs)) and compare the results with the permissible limits set by the 2003 Directive on Restriction of Hazardous Substances (RoHS). All the selected samples were pulverized and digested with strong acids. Inductively coupled plasma-mass spectrometry was used to measure the heavy metal content in each sample. The results revealed that concentration levels of the examined heavy metals were higher in PCBs, followed by PH and LCD in that particular order (PCB>PH>LCD). With the exception of Pb and Cr present in PCBs of mobile phones released before the year 2006, all the other metal concentrations were according to the Directive. Concentration levels of Cd, Hg were lower than the permissible limits set by the EU, either before or after the validity of the 2003 RoHS Directive. Considering their significant heavy metal content, coupled with their large quantities produced worldwide in an annual rate, waste cellular phones need to be treated under an environmentally sound management scheme, prioritizing recycling and at the same time eliminating the possibility of any harm.
VO2 as one of the most prospective cathode materials applied for lithium-ion batteries, has appealed increasing attentions owing to its high theoretical specific capacity, unique tunnel structure, as well as low cost. Among multiple methods to optimize the electrochemical performances of VO2(B), heteroatom-doping has attracted increasing interests owing to its efficiently adjusting the microstructure and interplanar distances of VO2(B). Here, W-doped VO2(B) nanosheets-built 3D networks are obtained readily via a hydrothermal route by oxalic acid reduction of vanadium pentoxide. The resultant 3D networks possess ultrathin nanowalls, interconnected structure and enlarged tunnels, which are advantageous for the easy access of electrolyte and fast diffusion of lithium ions. As a consequence, high reversible specific capacity of 304 mAh g−1, ultrahigh rate capability (200 mAh g−1 at 2 A g−1), and high-temperature electrochemical performances are achieved as the 3D networks are applied for lithium storage.
A solid polymer electrolyte (SPE) for calcium-ion conduction was produced and characterized. Poly(ethylene glycol) diacrylate was photocrosslinked under blue light in the presence of calcium salt to form a stable network with high thermal stability and promising conductivity. An ionic conductivity of 3.4 × 10−4 S/cm at 110 °C and 3.0 × 10−6 S/cm at room temperature was achieved, which is similar to early-stage lithium SPEs. The electrolytes evaluated under thermogravimetric analysis (TGA) remained stable up to temperatures of approximately 140 °C. XRD confirmed no salt precipitation within the polymer matrix, and Raman analysis indicated the complexation of the calcium ions to the PEGDA network. This study is a contribution towards suitable polymer electrolytes for solid-state calcium-ion batteries.
Improving the electron conductivity and lithiated structure stability for Si anodes can result in high stable capacity in cells. A Silicon/Wolfram Carbide@Graphene (SW@G) composite anode is designed and produced by a simple two-step ball milling the mixture of coarse-grained Si with good conductive wolfram carbide (WC) and graphite. The SW@G composite consists of multiple-scale WC particles, which are uniformly distributed in amorphous Si matrices, and wrapped by graphene nanosheets (GNs) on the outside. Owing to the unique concrete-like core-shell structure, the wrapping of GNs on the Si improves the conductivity and structural stability of the composite. The inner WC particles which tightly connect the Si and graphene act as the cornerstone to resist large volumetric expansion of Si during charge/discharge, and in particular serve as the high-speed channels of electrons as well as provide more interface paths for Li+ to accelerate their transfer inside the Si. These contribute to the excellent electrochemical properties of SW@G composite anode, including high volumetric capacity (three times higher than that of graphite), superior rate capability, and long-life stable cycleability. The synthetic method developed in this work paves the way for large-scale manufacturing of high performance Li storage anodes using commercially available materials and technologies.
A facile, green and highly efficient method for the decoration of carbon nanotubes with ZnO was developed for the fabrication of binder-free composite electrode for supercapacitor applications. The nano composite was prepared by using reactive magnetron sputtering in Ar/O2 environment. This approach leads to more uniform coating with tuneable thickness, which alters the electrochemical performance of the nano composite electrodes. The structure and surface morphology of the composite film have been studied by means of X-ray diffraction (XRD) analysis, scanning electron microscopy and field emission scanning electron microscopy (FESEM). The XRD study reveals the formation of Wurtzite ZnO structure. The electrochemical performance of nano composite electrode was investigated using cyclic voltammetry, chronopotentiometry and electrochemical impedance measurements in non-aqueous electrolyte. The nano composite electrode shows significant increase in the specific capacitance up to 48Fg−1 with an energy density 13.1Whkg−1 in the potential range −2V to 1V.
Studies of polymer electrolyte solutions for lithium-polymer batteries are described. Two different salts, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium trifluoromethanesulfonate (LiTf), were dissolved in a variety of polymers. The structures were all based upon the ethylene oxide unit for lithium ion solvation, and both linear and comb-branch polymer architectures have been examined. Conductivity, salt diffusion coefficient and transference number measurements demonstrate the superior transport properties of the LiTFSI salt over LiTf. Data obtained on all of these polymers combined with LiTFSI salts suggest that there is a limit to the conductivity achievable at room temperature, at least for hosts containing ethylene oxide units. The apparent conductivity limit is 5×10−5 S/cm at 25°C. Providing that the polymer chain segment containing the ethylene oxide units is at least 5–6 units long, there appears to be little influence of the polymer framework to which the solvating groups are attached. To provide adequate separator function, the mechanical properties may be disconnected from the transport properties by selection of an appropriate architecture combined with an adequately long ethylene oxide chain. For both bulk and interfacial transport of the lithium ions, conductivity data alone is insufficient to understand the processes that occur. Lithium ion transference numbers and salt diffusion coefficients also play a major role in the observed behavior and the transport properties of these polymer electrolyte solutions appear to be quite inadequate for ambient temperature performance. At present, this restricts the use of such systems to high temperature applications. Several suggestions are given to overcome these obstacles.
A highly transparent electrochromic capacitive (ECC) window was explored by combining a high contrast electrochromic polymer (ECP) and a transparent capacitive polymer. A blue and a red color ECP, poly(3,3-bis(bromomethyl)-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine) (PR-Br) and poly(3,4-di(2-ethylhexyloxy)thiophene-co-3,4-di(methoxy)thiophene) (Th-OR), respectively, were introduced into an ECC window having a thin polyaniline (PANI) film as a capacitive layer. The as prepared ECC window showed high transparency (>72% for PR-Br), large color contrast, and long capacitive stability over 10000 cycles, by combining non-aqueous acidic electrolyte and precise control of each electrode's working potential using in situ potential matching. Upon introducing a dielectric poly(methylmethacrylate) (PMMA) layer, the blue ECC window made of PR-Br and PANI showed bistable ECC properties, along with a high energy density of 9.7 and 13.5 W h kg−1 with a power density of 75.3 and 58.8 kW kg−1, respectively, for bleaching and coloring. The red ECC window made of Th-OR and PANI also showed a high energy density (10.5 W h kg−1). The energy stored in an ECC window could be transferred to another device, like a battery, to switch the color or to light a LED when the ECC window is connected in series. Thus the ECC window in this study functions as a color switching smart window and a rechargeable battery, to provide a new path to achieve energy saving EC windows with multi-color tunability. The working principle of these ECC windows can be widely applied in various electrochemical devices for multiple functions in one device.
Future scenarios and assessment studies used to prepare for long-term energy transitions and develop robust strategies to address climate change are highly dependent on the assessment of technology characteristics and availability. The electric power sector in the United States recently experienced a significant cost escalation: e.g., construction costs for large plants such as nuclear and coal-fired power plants doubled between 2003 and 2007. We assess the main drivers of this escalation. While many factors have affected costs, some of the most significant include cost of materials, particularly the price of metals and to a lesser extent cement, possible increases in labor quantity requirements, the aggressive worldwide competition for power plant design and construction resources, driven by high demand in Asia, market and regulatory changes, and general uncertainty about future regulations and climate policies. We recalibrate power sector technology costs in the Global Change Assessment Model (GCAM) based on an extensive literature review of recent (post-2010) studies and in the process develop a coherent and updated set of current cost and performance assumptions for all major electricity-generating technologies. While current cost and performance assumptions of electricity-generating technologies are key drivers of short-term technology deployment and technology mix in the electricity sector, medium- and long-term deployment pathways are significantly affected by assumed efficiency improvement rates and cost reductions. We develop and demonstrate a method to project efficiency and construction cost of power plants and report a sensitivity analysis to explore the importance of such assumptions in future scenarios generated by GCAM.
The vanadium redox flow battery (VRFB) has emerged as a viable grid-scale energy storage technology that offers cost-effective energy storage solutions for renewable energy applications. In this paper, a novel methodology is introduced for modeling of the transport mechanisms of electrolyte flow, species and charge in the VRFB at the pore scale of the electrodes; that is, at the level where individual carbon fiber geometry and electrolyte flow are directly resolved. The detailed geometry of the electrode is obtained using X-ray computed tomography (XCT) and calibrated against experimentally determined pore-scale characteristics (e.g., pore and fiber diameter, porosity, and surface area). The processed XCT data is then used as geometry input for modeling of the electrochemical processes in the VRFB. The flow of electrolyte through the pore space is modeled using the lattice Boltzmann method (LBM) while the finite volume method (FVM) is used to solve the coupled species and charge transport and predict the performance of the VRFB under various conditions. An electrochemical model using the Butler–Volmer equations is used to provide species and charge coupling at the surfaces of the carbon fibers. Results are obtained for the cell potential distribution, as well as local concentration, overpotential and current density profiles under galvanostatic discharge conditions. The cell performance is investigated as a function of the electrolyte flow rate and external drawing current. The model developed here provides a useful tool for building the structure–property–performance relationship of VRFB electrodes.
TiO2 nanotube arrays (NTAs) decorated with controllable Ag particles were prepared by pulse reverse current deposition in AgNO3/NaNO3 aqueous solution, aiming to improve the photoelectrochemical properties of TiO2 NTA electrode in visible-light region. By tuning the pulse current density and deposited charge density, a controllable synthesis of Ag structures was achieved. Excellent photocurrent responses of TiO2 NTAs in UV and visible light regions were achieved by depositing Ag nanorods and nanoparticles, which was attributed to highly efficient charge separation by the Schottky junction at the Ag/TiO2 interface and localized surface plasmon resonance effect of Ag nanostructures.
We have prepared NiO particles on Ni sheet and Ni foam substrates by chemical bath deposition and the following heat-treatment, and assembled a hybrid capacitor (HC) cell with the NiO-loaded Ni sheet or Ni foam positive electrode and activated carbon negative electrode. The deposited NiO particles had flower-like porous morphology which was composed of aggregated nanosheets. The maximum operating voltage of both HC cells was 1.5V, which was much higher than theoretical decomposition voltage of water (1.23V). The HC cell with NiO/Ni foam (HCfoam) had higher discharge capacitance and high-rate dischargeability and lower IR drop than the HC cell with NiO/Ni sheet (HCsheet) because of the increase in the utilization of NiO active material. Both energy and power densities per mass of active materials, were much higher than those for the HCsheet. Both HCfoam and HCsheet showed excellent cycle stability for 2000 cycles.
Electrochemical and physical measurements elucidate several thermodynamic properties and chemical factors that affect the performance of a non-aqueous all-vanadium flow battery. An H-type test cell was constructed that demonstrates stable coulombic efficiencies of 70% without flow after several weeks of slow cycling, with a steady plateau voltage near 1.7V during most of the discharge step. Environmental oxygen and water are associated with side reactions that affect long-term charge/discharge response of the battery. Oxygen passivates the electrode and may react with the solvent or supporting electrolyte, while water can cause the formation of oxovanadium complexes. Reversible cycling of the vanadyl acetylacetonate complex appears possible.
It is an effective method by synthesizing one-dimensional nanostructure to improve the rate performances of cathode materials for Li-ion batteries. In this paper, Li3V2(PO4)3 nanorods were successfully prepared by hydrothermal reaction method. The structure, composition and shape of the prepared were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scan electron microscope (SEM) and transmission electron microscope (TEM), respectively. The data indicate the as-synthesis powders are defect-rich nanorods and the sizes are the length of several hundreds of nanometers to 1μm and the diameter of about 60nm. The preferential growth direction of the prepared material was the [120]. The electrodes consisting of the Li3V2(PO4)3 nanorods show the better discharge capacities at high rates over a potential range of 3.0–4.6V. These results can be attributed to the shorter distance of electron transport and the fact that ion diffusion in the electrode material is limited by the nanorod radius. All these results indicate that the resulting Li3V2(PO4)3 nanorods are promising cathode materials in lithium-ion batteries.
Various screening tools have been proposed to identify HIV-Associated Neurocognitive Disorder (HAND). However, there has been no systematic review of their strengths and weaknesses in detecting HAND when compared to gold standard neuropsychological testing. Thirty-five studies assessing HAND screens that were conducted in the era of combination antiretroviral therapy were retrieved using standard search procedures. Of those, 19 (54 %) compared their screen to standard neuropsychological testing. Studies were characterised by a wide variation in criterion validity primarily due to non-standard definition of neurocognitive impairment, and to the demographic and clinical heterogeneity of samples. Assessment of construct validity was lacking, and longitudinal useability was not established. To address these limitations, the current review proposed a summary of the most sensitive and specific studies (>70 %), as well as providing explicit caution regarding their weaknesses, and recommendations for their use in HIV primary care settings.