batterydata/paper-abstracts huggingface dataset:
Flexible and free-standing MoS2/GS films are constructed for the first time based on a novel heat-induced formation process, during which self-generated gaseous species successfully trigger the formation of porous structure, without the assistance of any templates or spacers. Graphene forms an open porous network, with few-layered MoS2 uniformly grown on the surface of GS. The fascinating structure provides several attractive features as anode material, including efficient ion transport, high conductivity and good structure durability. When used as free-standing and binder-free electrodes for lithium-ion batteries, the optimized hybrid film with graphene content of 32% exhibits superior rate capability (994, 880, and 598mAhg−1 at 0.5, 1, and 5Ag−1, respectively) and outstanding cycling performance at high rates (retaining 100.6% of the initial capacity after 1000 cycles at 1000mAg−1). Importantly, the electrochemical reaction kinetics and interfacial behavior of the hybrid electrode are also in-depth investigated by EIS and morphological study. The work described here can be extended to prepare various porous graphene-based hybrid films, for the application in a broad range of LIBs, electrochemical capacitors, sensors, and catalysts.
A new organic-inorganic solid hybrid electrolyte based on 2,4,6-trichloro-1,3,5-triazine, triblock co-polymer poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) bis(2-aminopropyl ether), poly(ethylene glycol) diglycidyl ether, and 3-(glycidyloxypropyl)trimethoxysilane doped with LiClO4 salt is synthesized by a sol-gel process. Fourier transform infrared spectroscopy and 13C NMR results reveal the successful synthesis of the organic-inorganic hybrid electrolyte. The conductivity of the hybrid electrolyte follows a VTF (Vogel-Tamman-Fulcher)-like behavior, implying that the diffusion of charge carriers is assisted by the segmental motions of polymer chains. The Li-ion mobility is determined from 7Li static NMR linewidth and diffusion coefficient measurements; both are correlated with their ionic conductivities. The maximum ionic conductivity of 9.5×10−5 Scm−1 at 30°C is obtained for the hybrid electrolyte with the [O]/[Li] ratio of 32. The electrochemical stability window of 4V ensures the hybrid electrolyte as a potential candidate for low voltage lithium ion batteries.
A simple analytical model of a layered system comprised of a single passage of a serpentine flow channel and a parallel underlying porous electrode (or porous layer) is proposed. This analytical model is derived from Navier–Stokes motion in the flow channel and Darcy–Brinkman model in the porous layer. The continuities of flow velocity and normal stress are applied at the interface between the flow channel and the porous layer. The effects of the inlet volumetric flow rate, thickness of the flow channel and thickness of a typical carbon fiber paper porous layer on the volumetric flow rate within this porous layer are studied. The maximum current density based on the electrolyte volumetric flow rate is predicted, and found to be consistent with reported numerical simulation. It is found that, for a mean inlet flow velocity of 33.3 cm s−1, the analytical maximum current density is estimated to be 377 mA cm−2, which compares favorably with experimental result reported by others of ∼400 mA cm−2.
Cognition, negative symptoms, and depression are potential predictors of disability in schizophrenia. We present analyses of pooled data from four separate studies (all n>169; total n=821) that assessed differential aspects of disability and their potential determinants. We hypothesized that negative symptoms would predict social outcomes, but not vocational functioning or everyday activities and that cognition and functional capacity would predict vocational functioning and everyday activities but not social outcomes. The samples were rated by clinician informants for their everyday functioning in domains of social and vocational outcomes, and everyday activities, examined with assessments of cognition and functional capacity, rated clinically with the Positive and Negative Syndrome Scale (PANSS) and self-reporting depression. We computed a model that tested the hypotheses described above and compared it to a model that predicted that negative symptoms, depression, cognition, and functional capacity had equivalent influences on all aspects of everyday functioning. The former, specific relationship model fit the data adequately and we subsequently confirmed a similar fit within all four samples. Analyses of the relative goodness of fit suggested that this specific model fit the data better than the more general, equivalent influence predictor model. We suggest that treatments aimed at cognition may not affect social functioning as much as other aspects of disability, a finding consistent with earlier research on the treatment of cognitive deficits in schizophrenia, while negative symptoms predicted social functioning. These relationships are central features of schizophrenia and treatment efforts should be aimed accordingly.
Carbon nanotube-encapsulated SnO2 (SnO2@CNT) core–shell composite anode materials are prepared by chemical activation of carbon nanotubes (CNTs) and wet chemical filling. The results of X-ray diffraction and transmission electron microscopy measurements indicate that SnO2 is filled into the interior hollow core of CNTs and exists as small nanoparticles with diameter of about 6nm. The SnO2@CNT composites exhibit enhanced electrochemical performance at various current densities when used as the anode material for lithium-ion batteries. At 0.2mAcm−2 (0.1C), the sample containing wt. 65% of SnO2 displays a reversible specific capacity of 829.5mAhg−1 and maintains 627.8mAhg−1 after 50 cycles. When the current density is 1.0, 2.0, and 4.0mAcm−2 (about 0.5, 1.0, and 2.0C), the composite electrode still exhibits capacity retention of 563, 507 and 380mAhg−1, respectively. The capacity retention of our SnO2@CNT composites is much higher than previously reported values for a SnO2/CNT composite with the same filling yield. The excellent lithium storage and rate capacity performance of SnO2@CNT core–shell composites make it a promising anode material for lithium-ion batteries.
This paper details the design, deployment and operation of a power take off system for a 1:4 scale offshore Oscillating Water Column (OWC) Wave Energy Converter (WEC). Ocean energy device prototypes at this scale present a unique set of challenges in that the integration of prime movers and generators typically begins to take place at this particular development stage, which may also represent first deployment at sea.The presence of electrical equipment and rotating machinery in the offshore environment brings its own engineering and operational difficulties. Moreover, such devices are typically not grid connected, necessitating the development of custom power conversion and control equipment. The paper describes the design considerations, details of design, deployment experiences, operational experiences of such a system and concludes with recommendations for future projects in the area.
Power outages can impact health, and certain populations may be more at risk. Personal preparedness may reduce impacts, but information on power outage preparedness and risk perception among vulnerable populations is limited. We examined power outage preparedness and concern among New York City residents, including vulnerable populations defined as older adults (≥ 65 years), and respondents with household members who require assistance with daily activities or depend on electric medical devices. A random sample telephone survey was conducted during November–December 2016. Preparedness was defined as having a three-day supply of drinking water, non-perishable food, and a working flashlight. Among all respondents (n = 887), 58% were prepared and 46% expressed concern about health. Respondents with electric-dependent household members (9% of all respondents) tended to have higher preparedness (70 vs. 56% of respondents without electric-dependent household members). Among this group, only 40% reported being registered with a utility company to receive early notification of outages. While the subgroup sample was small, respondents with registered electric-dependent household members had lower preparedness than those with non-registered users (59 vs. 76%). Respondents with household members who needed assistance had comparable levels of preparedness to respondents without someone who needed assistance (59 vs. 57%). Older adults had greater preparedness than younger adults (65 vs. 56%). Health concerns were greater among all vulnerable groups than the general population. Levels of preparedness varied among vulnerable respondents, and awareness of power outage notification programs was low. Our findings highlight the need to increase awareness and preparedness among at-risk people.
Redox flow batteries (RFBs) are potential solutions for grid-scale energy storage, and deeper understanding of the effect of flow rate on RFB performance is needed to develop efficient, low-cost designs. In this study we highlight the importance of modeling tanks, which can limit the charge/discharge capacity of redox-active polymer (RAP) based RFBs. At low flow rates the losses due to tank mixing dominate over the polarization-induced capacity losses that arise due to resistive processes in the reactor. A porous electrode model is used to separate these effects by predicting the time variation of active species concentration in electrodes and tanks. A simple transient model based on species conservation laws developed in this study reveals that charge utilization and polarization are affected by two dimensionless numbers quantifying (1) flow rate relative to stoichiometric flow and (2) size of flow battery tanks relative to the reactor. The RFB’s utilization is shown to increase monotonically with flow rate, reaching 90% of the theoretical value only when flow rate exceeds twenty-fold of the stoichiometric value. We also identify polarization due to irreversibilities inherent to RFB architecture as a result of tank mixing and current distribution internal to the reactor, and this polarization dominates over that resulting from ohmic resistances particularly when cycling RFBs at low flow rates and currents. These findings are summarized in a map of utilization and polarization that can be used to select adequate flow rate for a given tank size.
The electrochemical properties of the Li-ion battery with a lithium manganese oxide (LiMn2O4) cathode are improved by efficiently reducing the reaction between LiMn2O4 and hydrofluoric acid (HF) produced in the electrolyte. By introducing fine ZrO2 particles in the slurry during fabrication, Mn dissolution of the cathode during the charge–discharge cycles is minimized by scavenging the HF produced in the cell. Results from galvanostatic experiments show that the capacity retention of the LiMn2O4 fabricated with new method is maintained up to 92% after 50 cycles at room temperature and 76% at high temperature without losing initial capacity. The improvement in the electrochemical properties of the cathode prepared by this method is superior to other approaches in terms of fabrication process and it sheds light on the possibility of further improving the electrochemical properties of LiMn2O4.
The article features a temporal approach to analyzing the impact of Western colonialism on contemporary levels of democracy. We present a new data set with dates of colonization, independence, and a colonizing event for all former colonies and dependencies that are regarded as countries today (143 observations). Our data, as well as the existing literature, suggest that the very heterogeneous era of colonization should be divided into an early ‘mercantilist’ wave and a much later ‘imperialist’ wave with quite different characteristics. We show that there is a strong positive effect of colonial duration on democracy, an effect which turns out to be driven primarily by former British colonies and by countries colonized during the imperialist era.
The role of different types of infections in heart diseases is more important than commonly thought, with new and re-emerging infections (i.e., Mycobacterium tuberculosis). This review addresses the pathology of infective pericarditis, myocarditis, and endocarditis, mainly focusing on the significance of molecular techniques in the detection of infective agents. Molecular investigations represent important ancillary diagnostic tools and combined with other conventional approaches provide a more precise final diagnosis. A close collaboration and communication among cardiologists, cardiac surgeons, pathologists, and microbiologists is essential to ensure optimal diagnoses and management as well as a favorable impact on patient outcome.
Early embryogenesis is one of the most sensitive and critical stages in animal development. Here we propose a new assessment model on the effect of pollutant to multicellular organism development. That is a comparison between the whole embryo assay and the blastomere culture assay. We examined the LiCl effect on the sea urchin early development in both of whole embryos and the culture of isolated blastomeres. The mesoderm and endoderm region were capable to differentiate into skeletogenic cells when they were isolated at 60-cell stage and cultured in vitro. The embryo developed to exogastrula by the vegetalizing effect of the same LiCl condition where ectodermal region changed their fate to endoderm, while the isolated blastomeres from the presumptive ectoderm region differentiated into skeletogenic cells in the culture with LiCl. The effect of LiCl to the sea urchin embryo and to the dissociated blastomere is a unique example where same cells response distinctly to the same agent depend on the condition around them. Present results show the importance of examining the process in cellular and tissue levels for the exact understanding on the morphological effect of chemicals and metals.
SnO2-based nanostructures have attracted considerable interest as a promising high-capacity anode materials for lithium ion batteries. We present herein a facile one step hydrothermal approach for in situ growth of SnO2 nanoparticles in heteroatoms doped cross-linked carbon framework (NSG/CNTs@SnO2). Thiourea is employed as a single source of nitrogen and sulfur in the cross-linked carbon framework (NSG/CNTs). Characterization shows that the SnO2 nanoparticles with an average size of 6–10nm are uniformly anchored on NSG/CNTs matrix. When evaluated for the electrochemical properties in lithium ion batteries, the obtained NSG/CNTs@SnO2 composite with ultrasmall SnO2 particle size (6–10nm) delivers a high reversible capacity of 999mAhg−1 at 200mAg−1 after 120 cycles and excellent rate performance. Such outstanding electrochemical performance of the peculiar cross-linked NSG/CNTs@SnO2 composite can be primarily attributed to the synergistic effect of the ultrasmall anchored SnO2 nanoparticles and the dual-doped NSG/CNTs matrix. The uniformly distributed SnO2 nanoparticles can deliver large capacity and the robust dual-doped NSG/CNTs matrix can guarantee the good structural integrity and high electrical conductivity during cycling. Besides, the porous structure can provide free space for the volume expansion of SnO2 and accommodate the strain formed during repeated lithiation/delithiation processes.
The electrical properties of conducting polymers make them useful materials in a wide number of technological applications. In the last decade, an important effect on the properties of the conducting polymer when iron oxides particles are incorporated into the conductive matrix was shown. In the present study, films of polypyrrole were synthesized in the presence of magnetite particles. The effect of the magnetite particles on the structure of the polymer matrix was determined using Raman spectroscopy. Mass variations at different concentrations of Fe3O4 incorporated into the conducting matrix were also measured by means of quartz crystal microbalance. Additionally, the changes in the resistance of the films were evaluated over time by electrochemical impedance spectroscopy in solid state. These results show that the magnetite incorporation decreases polymeric film resistance and Raman experiments have evidenced that the incorporation of magnetite into polymeric matrix not only stabilizes the polaronic form of the polypyrrole, but also preserves the polymer from further oxidation.
Lead is classified to be one of the top heavy metal pollutants in China. The corresponding environmental issues especially during the management of spent lead-acid battery have already caused significant public awareness and concern. This research gives a brief overview on the recycling situation based on an investigation of the lead industry in China and also the development of technologies for spent lead-acid batteries. The main principles and research focuses of different technologies including pyrometallurgy, hydrometallurgy and greener technologies are summarized and compared. Subsequently, the circulability of lead based on the entire life cycle analyses of lead-acid battery is calculated. By considering different recycling schemes, the recycling situation of spent lead-acid battery in China can be understood semi-quantitatively. According to this research, 30% of the primary lead production can be shut down that the lead production can still ensure consecutive life cycle operation of lead-acid battery, if proper management of the spent lead-acid battery is implemented according to current lead industry situation in China. This research provides a methodology on the view of lead circulability in the whole life cycle of a specific product and is aiming to contribute more quantitative guidelines for efficient organization of lead industry in China.
Cobalt–tin and cobalt–tin–carbon composite electrodes with different nominal compositions (CoSn, CoSn2, CoSn3, CoSn4, CoSn15 and [CoSn3]0.6C0.4) have been prepared by annealing of the elements under an argon flow. 119Sn Mössbauer spectra have been recorded. As a consequence of the electronic transfer from tin atoms to the resulting cobalt–tin intermetallic compounds, the isomer shift barycentre is moved to lower values as compared to pure tin (δ =2.5mm/s). The lower isomer shift values (δ ∼2.0mm/s) for cobalt–tin samples with cobalt to tin atomic ratio equal to 1:3 are obtained for a preparation temperature between 450 and 750°C. In contrast, the presence of carbon atoms limits the isomer shift of the tin-based intermetallic phases, with δ =2.2mm/s for [CoSn3]0.6C0.4 nominal composition in the 450–750°C range, and then the electronic transfer from tin atoms to the resulting intermetallic phase is reduced. The carbon atoms exert an effect in the isomer shift value (increase of δ) that is in opposition to the effect exerted by lithium and cobalt atoms (decrease of δ). After treating with a hydrochloric acid aqueous solution, the 119Sn Mössbauer spectra are less broadened and the electrochemical behaviour in lithium cells is greatly improved. Reversible specific capacities of around 700mAhg−1 are observed between 1 and 0V for acid-treated cobalt–tin–carbon electrodes. The mechanism of the reaction with Li is explored by using ex situ 119Sn Mössbauer spectroscopy. In the charge process (Li-removing) two phases are segregated from the original lithiated phase.
A modified ball-milling-assisted green solid reaction method is provided to prepare Li4Ti5O12/C composite materials with controllable carbon content. Thermal analysis was utilized to investigate the reaction process and the temperature for eliminating carbon. The added carbon and the time for eliminating the carbon can affect the particle size and greatly improve the cycling stability and rate performance. Besides, the particle size can reach ~60 nm, the Li4Ti5O12 eliminated carbon at 600 °C has ~178% higher discharge capacity than that without added carbon after 500 cycles under the same conditions. As for the Li4Ti5O12 with a carbon weight of 10.6%, the second discharge capacity can reach 177.2 and 120.8 mAh g−1 at 1 and 20 C rates, respectively. Its discharge capacity still remains at 118.3 mAh g−1 after 500 cycles under various current rates. The results are comparable to those of the reported Li4Ti5O12/PAS composite.
The recovering of valuable metals in spent lithium-ion battery cathodes brings about economic and environmental benefits. A stepwise leaching-flotation-precipitation process is adopted to separate and recover Li/Fe/Mn from the mixed types of cathode materials (hybrid wastes of LiFePO4 and LiMn2O4). The optimal operating conditions for the stepwise recovery process are determined and analyzed by factorial design, thermodynamics calculation, XRD and SEM characterization in this study. First, Li/Fe/Mn ions are released from the cathode using HCl assisted with H2O2 in the acid leaching step. The leachability of metals follows the series Li > Fe > Mn in the acidic environment. Then Fe3+ ions are selectively floated and recovered as FeCl3 from the leachate in the flotation step. Finally, Mn2+/Mn3+ and Li+ ions are sequentially precipitated and separated as MnO2/Mn2O3 and Li3PO4 using saturated KMnO4 solution and hot saturated Na3PO4 solution, respectively. Under the optimized and advisable conditions, the total recovery of Li, Fe and Mn is respectively 80.93 ± 0.16%, 85.40 ± 0.12% and 81.02 ± 0.08%. The purity for lithium, ferrum and manganese compounds is respectively 99.32 ± 0.07%, 97.91 ± 0.05% and 98.73 ± 0.05%. This stepwise process could provide an alternative way for the effective separation and recovery of metal values from spent Li-ion battery cathodes in industry.
The subcutaneous implantable cardioverter-defibrillator (S-ICD) is a novel technology for the treatment of sudden cardiac death. The system consists of a pulse generator implanted in the left axillary position and a single subcutaneous lead for detection and delivery of therapy. Initial clinical trials of S-ICDs demonstrated improved safety and efficacy when compared to transvenous ICD systems, leading to their widespread approval. The main advantage of the S-ICD is the avoidance of vascular access and the complications associated with transvenous leads. Owing to limitations of S-ICDs, patients who require pacing support or antitachycardia pacing are not candidates for the device; instead, this system is currently used most commonly in young patients with previous lead malfunction, limited vascular access, or low risk for subsequent bradycardia or antitachycardia pacing. Findings from device trials support S-ICDs as a viable alternative to transvenous ICDs in certain patients, and the current limitations associated with S-ICDs are likely to be addressed in future iterations of the device, extending its indications and target patient populations.