batterydata/paper-abstracts huggingface dataset:
The research on preparation and application of defect-free pristine graphene (PG) is a hot topic. However, large-scale non-destructive exfoliation of graphite into single-layered PG still remains a challenge. The common method of exfoliating graphite is based on the oxidation-exfoliation-reduction strategy. Nevertheless, there are many structural defects for the graphene produced by this approach due to the excessive oxidation and incomplete reduction processes, which significantly deteriorate the intrinsic properties of graphene. Therefore, researchers attempt to develop non-oxidative chemical/physical methods to directly exfoliate graphite into PG layers without damaging the sp2 carbon lattice, and utilize PG-based materials and structures for various applications. Herein, we review recent development on the direct exfoliation of graphite into PG via non-oxidative chemical methods. Firstly, we outline the various exfoliation systems based on different acting forces as well as liquid media, which are two key factors determining the ultimate exfoliation effect. Then the structural qualities of the PG sheets are discussed. Finally, we summarize in detail the diverse electrochemical energy applications of PG materials, and provide some perspectives for the future developments of PG materials towards commercialization.
Li-air cell operated with ionic liquid electrolytes is a very promising energy storage technology for electric vehicle and plug-in hybrid electric vehicle due to several favorable characteristics of ionic liquids. However, Li-air cells that employ room temperature ionic liquid (RTIL) electrolytes exhibit poor performance due to limited oxygen solubility and low reactant species mobility. To circumvent these aforementioned drawbacks, we investigated the electrical performance of a Li-air cell with ionic liquid electrolytes operating at high temperature. A continuum based model is used to quantify the performance of the Li-air cell, with an ionic liquid (MPPY-TFSI) electrolyte, as a function of operating temperature. Simulations at the atomistic scale, such as molecular dynamics (MD) and density functional theory (DFT) calculations are used to obtain key properties for the continuum model. These properties include electron transfer reaction rate constant, species diffusivity and oxygen solubility. The MD simulations indicate that oxygen solubility in ionic liquid increases with temperature, which is very favorable for high temperature operation. The continuum based cell level simulation results show that the battery performance can be improved significantly by increasing operating temperature. For instance, specific capacity as high as 3000mAh/g can be achieved at 110°C operating temperature, which is almost 25 times higher than its counterpart at room temperature. Simulation results also reveal that by increasing the operating temperature, the specific capacity can be improved significantly for high load current density, which is one of the most critical drawbacks in RTIL based Li-air battery. We also studied the effect of cathode thickness on the performance of Li-air battery at different operating temperatures. The transport limitation of oxygen and lithium ions can be alleviated at higher operating temperatures, suggesting that even thicker cathode materials can be used to enhance the cell capacity at elevated temperature.
The penetration of plug-in electric and hybrid-electric vehicles (PEVs and PHEVs) will increase significantly in the next 20 years. The insertion of PEVs in households will facilitate the use of renewable sources and possibly create economic benefits to users, as shown in a Mexican example here presented, but also will introduce some challenges such as how the penetration of PEVs affect the quality of existing power grids. The contribution of this work is to review the literature in reference to the power quality problems and to test them in a real distribution system based on the Mueller community in Austin, Texas that has PEVs and photovoltaic panels (PVs). The results show that a coordinated delay charge mode reduces the loading on transformers at peak hours and improves voltage regulation. Additionally, it is shown that photovoltaic panels introduce a power factor reduction during daytime in the main feeder. Corrective measures should be considered for high levels of PV penetration, such as reactive power support, VAr compensators or community energy storage, which can be presented as one potential solution to most of the problems listed in current literature. However, more research needs to be done in a much broader scale because power systems differ from each other and between countries, but there is a consensus that high power demand by PEVs leads to voltage statutory violations at some points in the grid and smart charging is required to operate the system efficiently.
In this work, a uniform heterojunction of cupric oxide/cuprous oxide was decorated on the surface of carbon fibers by electrochemical method (CuO/Cu2O/CDs/CFs). Methyl-β-cyclodextrin was first grafted on the surface of carbon fibers (CDs/CFs). Cubic cuprous oxide was electrodeposited on the surface of (Cu2O/CDs/CFs) in 0.1 M KNO3, the cuprous oxide was then partly anodized to cupric oxide to form a heterojunction of cupric oxide/cuprous oxide with a burr shape (CuO/Cu2O/CDs/CFs). The obtained materials were characterized by field emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and electrochemical techniques. The potential application in pollution treatment was further investigated, and the prepared CuO/Cu2O/CDs/CFs could be a promising adsorbent/photocatalyst toward the uptake and degradation of 2, 6-dichlorophenol (2, 6-DCP).
Abstract There are various types of measurements and controls accomplished through sensors and transmitters. Pressure, temperature, flow, and level types of general measurements are included in this chapter. Different types of pressure and temperature elements are deployed for respective measurements. Flow elements are often used as differential producers for flow measurements. Level measurements are often based on pressure and differential pressure measurements. Other types of flow and level measurements are also described. Working principle, specification/data sheets, and typical list of measurements are presented.
A coordinatively unsaturated copper–nitrogen architecture in copper metalloenzymes is essential for its capability to catalyze the oxygen reduction reaction (ORR). However, the stabilization of analogous active sites in realistic catalysts remains a key challenge. Herein, we report a facile route to synthesize highly doped and exposed copper(I)–nitrogen (Cu(I)–N) active sites within graphene (Cu–N©C) by pyrolysis of coordinatively saturated copper phthalocyanine, which is inert for the ORR, together with dicyandiamide. Cu(I)–N is identified as the active site for catalyzing the ORR by combining physicochemical and electrochemical studies, as well as density function theory calculations. The graphene matrix could stabilize the high density of Cu(I)–N active sites with a copper loading higher than 8.5 wt%, while acting as the electron-conducting path. The ORR activity increases with the specific surface area of the Cu–N©C catalysts due to more exposed Cu(I)–N active sites. The optimum Cu–N©C catalyst demonstrates a high ORR activity and stability, as well as an excellent performance and stability in zinc–air batteries with ultralow catalyst loading.
Several studies have suggested that patients with Parkinson’s disease (PD) have sentence comprehension difficulty in part because of their limited executive resources. However, these assessments confound the executive resources contributing to sentence comprehension with the resources needed for task performance. In the present study, we used a word detection technique that minimizes task demands in order to evaluate attentional and processing speed resources during the comprehension of simple sentences without subordinate clauses and sentences containing subject-relative and object-relative center-embedded subordinate clauses. We found that PD patients have poor sensitivity to phonetic errors embedded in unbound grammatical morphemes, regardless of the clausal structure of the sentence, suggesting difficulty attending to grammatical morphemes. We also found that PD patients are significantly slowed in their sensitivity to phonetic errors in content words embedded in object-relative center-embedded sentences. Slowed sensitivity to content words in object-relative sentences was correlated with timed executive measures of planning. On a traditional measure of comprehension, these PD patients were impaired for sentences containing object-relative center-embedded clauses compared to sentences with subject-relative center-embedded clauses, and comprehension of object-relative sentences was correlated with executive measures. Our findings are consistent with the claim that limited executive resources for strategic attention and processing speed contribute to the sentence comprehension difficulties of PD patients.
The purpose of this study was to explore the relationship of a history of depression with moderate physical activity and physical function before and after a physical activity intervention of congregate meal participants in senior centers from all 12 Georgia Area Agencies on Aging (AAA). Participants were a convenience sample of older adults (n =376, mean age=76 years, 82% female, 64% Caucasian, 36% African American, 22% a history of depression). The physical activity intervention included educator-led chair exercises that incorporated balls and bands. Pre- and post-tests assessed moderate physical activity and physical function. At the pre-test, a history of depression was not related to moderate physical activity or physical function. Following the intervention there were significant increases in both moderate physical activity and physical function, but a history of depression was a negative predictor of improvements in physical activity when controlled for site, demographics, and health-related conditions. These results provide an evidence base for the effectiveness of this intervention in improving moderate physical activity and physical function in a community setting, but additional efforts may be needed to improve the impact of this type of intervention among older adults with a history of depression.
A two-dimensional mathematical model for a flow-through porous electrode, in which the electrolyte flow is perpendicular to the current flow, is presented in this paper. In order to study the effects of ohmic resistance, mass transfer and kinetics on the performance of the porous electrode, a set of dimensionless parameters were imported into the model equations. The results reveal that lower ohmic resistance lead to a more uniform current density distribution, which will get a higher utilization of the electrode; an enhancement in convective mass transport will increase the reaction rate, but the increase is in a diminishing manner due to the limit of diffusion rate, so that the effective reaction layer will get thinner until to a limited value; an increase of local mass transfer coefficient will increase the reaction rate and make the effective reaction layer thinner; and the longer the electrode is, the worse the concentration polarization will be. The model could help to guide the rational design of the porous electrode and the operating parameters.
CoFe2O4 flower-like microspheres are prepared via a surfactant- and template-free method, involving the controlled hytrothermal synthesis firstly and a subsequent thermal decomposition treatment. The microspheres with diameters of 3–4 μm are characterized by the assembly of numerous porous and inter-connected lamella structures. Lithium-ion batteries electrodes based on the as-prepared CoFe2O4 microspheres show a high specific capacity of 733.5 mAh g−1 after 50 cycles at a current density of 200 mA g−1 and a good cyclic stability, as well as excellent rate capability. The enhanced electrochemical performance can be attributed to the hierarchical microsphere structure with high sufficient interfacial contact area between the microspheres and electrolyte, the short diffusion distance of Li+, better accommodation of structural stress and volume change with the lithiation/delithiation process. It is suggested that the CoFe2O4 microsphere is one of the most promising candidates for high-performance lithium-ion batteries.
In 1998, the US EPA announced the HPV Challenge Program, a voluntary chemical data collection effort. The Petroleum HPV Testing Group (PHPVTG 1 The Petroleum HPV Testing Group (PHPVTG) is an unincorporated group of manufacturers affiliated by contractual obligation to fund a voluntary data disclosure and toxicity testing program on certain petroleum-related chemical substances in response to EPA’s HPV Challenge Program. The American Petroleum Institute (API) manages the Group’s activities. 1 ) volunteered to provide data on approximately 110 high boiling petroleum substances (HBPS), i.e. substances with final boiling points ⩾approximately 650°F (343°C). These HBPS are substances of unknown and variable composition (UVCBs) that are composed of numerous individual constituents. Toxicity studies have shown that some HBPS can produce systemic (repeat-dose) and developmental effects, and some are mutagenic under in vitro conditions. The papers in this supplement show that these effects are related to the profiles of aromatic constituents in these substances. Further, it is shown that the effects on selected repeat-dose and developmental toxicity endpoints and mutagenic activity in bacterial assays can be predicted from compositional information using models based on the aromatic-ring class profile, “ARC profile” as defined by gas chromatographic separation of the DMSO-soluble fraction of the starting materials. This chromatographic method and the predictive models provide an efficient means of characterizing for screening purposes the potential for repeat-dose, developmental effects and bacterial mutagenicity of HBPS and can reduce the number of animal tests that would be required if these tests were conducted on all 110 HBPS.
NiCo2S4 single-shelled hollow polyhedrons (SSHPs) and double-shelled hollow polyhedrons (DSHPs) were synthesized by the same metal-organic-framework-engaged strategy that took advantage of the unique reactions of zeolitic imidazolate framework-67 and Ni(NO3)2, H2O, thiacetamide. It was found by XRD, SEM, TEM that the synthesized NiCo2S4 materials showed the hollow polyhedron structure assembled with nanocrystalline (the size was around 10–15 nm), and numerous mesopores existed among these nanocrystalline. As anode materials for lithium-ion batteries, NiCo2S4 SSHPs and DSHPs exhibited excellent cycling stability, but DSHPs were remarkably superior to SSHPs in terms of capacity performance and rate capability. At 0.1C, DSHPs could deliver the discharge capacity of 770.3 mAh g−1 at the 100th cycle, and the average discharge capacity over 100 cycles reached 745.5 mAh g−1. When the current came back to 0.1C after rate measurements, NiCo2S4 DSHPs could stably deliver the discharging capacity of 712.0 mAh g−1, reaching 92.1% of that at the initial 0.1C. The superior Li-storage performance should be attributed to the nanocrystalline, mesopore, and multi-shelled hollow polyhedron structure. The unique NiCo2S4 multi-shelled hollow polyhedrons exhibit great potential as anode materials for high-performance lithium-ion batteries.
Poly(vinylidene fluoride-co-trifluoroethylene), P(VDF-TrFE) solid polymer electrolytes were prepared using porous membrane soaked in lithium tetrafluoroborate (LiBF4), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), magnesium triflate (Mg(CF3SO3)2) and sodium triflate (Na(CF3SO3)) electrolyte solution. The effect of the uptake of different salts in the morphology, polymer phase, thermal and mechanical properties of the membrane was determined. The electrolyte uptake ranged from 396% for the LiTFSI salt to 529% for the Mg(CF3SO3)2. It is observed that ionic conductivity of the membrane is dependent of the anion size of the salts present in the electrolyte solution. Independently of the electrolyte solution, high ionic conductivity is obtained. In particular, the ionic conductivity for the LiTFSI salt increases from 0.32 to 1.2mS/cm when the temperature is increased from room temperature to 100°C. The porous membranes immersed in different electrolyte solutions show good electrochemical stability as determined by cycle voltammetry. It is observed that anion size is very important parameter that affects the uptake value and electric properties of the polymer electrolyte. It is concluded that the polymer electrolyte based on P(VDF-TrFE) porous membranes are adequate for battery separator applications.
Objective Somatic causal illness attributions are being considered as potential positive criteria for somatoform disorders (SFDs) in DSM-V. The aim of this study was to investigate whether patients diagnosed with SFDs tend towards a predominantly somatic attribution style. Methods We compared the causal illness attributions of 48 SFD and 149 non-somatoform disorder patients, in a sample of patients presenting for an allergy diagnostic work-up, and those of 47 controls hospitalised for allergen-specific venom immunotherapy. The SFD diagnosis was established by means of the Structured Clinical Interview for DSM-IV. Both spontaneous and prompted causal illness attributions were recorded through interview and by means of the causal dimension of the Revised Illness Perception Questionnaire (IPQ-R), respectively. Patients' spontaneous and prompted responses were assigned to a psychosocial, somatic, or mixed attribution style. Results Both in the free-response task and in their responses to the IPQ-R, SFD patients were no more likely than their nonsomatoform counterparts to focus on somatic explanations for their symptoms. They were just as likely to make psychosocial or mixed causal attributions. However, patients with SFDs were significantly more likely to find fault with medical care in the past. Conclusion Our data do not support the use of somatic causal illness attributions as positive criteria for SFDs. They confirm the dynamic and multidimensional nature of causal illness attributions. Clinical implications of these findings are discussed.
Lithium batteries have a tendency to fail violently under adverse conditions leading to the rapid venting of gas. Overcharge, thermal heating, and a combination of the two conditions are applied here to investigate the gas venting process. A test chamber has been constructed with data recordings including chamber pressure and temperature, battery voltage, current, and surface temperature as functions of time throughout the charging and failure processes. High-speed imaging and schlieren flow visualization are used to visualize the gas venting process. A direct comparison between lithium iron phosphate based K2 26650 and lithium nickel manganese cobalt oxide LG 18650 cells is made through a test series of the three failure methods. Failure under thermal, overcharge, and thermal-overcharge conditions are generally similar in terms of the gas venting process, but are observed to have increasingly energetic failures. The thermal-overcharge abuse condition demonstrates an ability to reconnect via internal short circuit even after an initial electrical failure seen as the refusal to accept charge. This reconnection is associated with a secondary, more energetic failure which can produce weak shock pressure waves.
A hierarchical hybrid nanostructure composed of NiMo3S4 nanosheet arrays with abundant exposed edges on flexible carbon textiles (denoted as NiMo3S4/CTs) has been designed and synthesized for sodium ion batteries (SIBs) and electrocatalytic hydrogen evolution reaction (HER). The novel NiMo3S4 nanostructure, formed by incorporating Ni2+ into Mo-S lattice, shows plenty of substantial defects and active sites, which are favorable for the improvement of the overall electrochemical performances for both SIBs and HER. When evaluated as the anode of SIBs, the NiMo3S4/CT electrode delivers a high specific capacity of ~ 480 mA h g−1 at a current density of 0.12 A g−1 and a high Coulombic efficiency of 100%. Moreover, the NiMo3S4/CT electrode shows an excellent long-term cycling performance with a high reversible capacity of ~ 302 mA h g−1 after 1000 cycles at 0.48 A g−1, showing a high capacity retention of 73.9%. Furthermore, as a HER catalyst, the NiMo3S4/CT hybrid nanostructure exhibits a low onset over-potential of 0.124 V, a small Tafel slope of 46.2 mV dec−1 as well as an excellent long-term stability, which are among the best values of current noble-metal-free electrocatalysts. These results may open up a new route to introduce more active defect sites to enhance the electrochemical performance of metal sulfides by incorporation of metal elements.
The development of efficient cellulase blends is a key factor for cost-effectively valorizing biomass in a new bio-economy. Today, the enzymatic hydrolysis of plant-derived polysaccharides is mainly accomplished with fungal cellulases, whereas potentially equally effective cellulose-degrading systems from bacteria have not been developed. Particularly, a thermostable multi-enzyme cellulase complex, the cellulosome from the anaerobic cellulolytic bacterium Clostridium thermocellum is promising of being applied as cellulolytic nano-machinery for the production of fermentable sugars from cellulosic biomass.
The Fe-doping LiMnPO4 (LiMn1−x Fe x PO4, x ≤ 0.5) nanomaterials are solvothermally synthesized in a mixed solvent of water and polyethylene glycol (PEG). The particle morphology can be controlled simply by adjusting the pH values of precursor suspensions. Electrochemical test shows that LiMn0.9Fe0.1PO4 nanoplates with a thickness of 20–30 nm could deliver the largest discharge capacity, which is attributed to the fast Li+ diffusion in the diffusion path of [010] crystallographic axis along the short radial direction of the nanoplates. It is demonstrated that Fe doping could significantly increase the initial reversible capacity, cycle performance and rate capability. The first discharge capacities of Fe-doped LiMnPO4 are all above 150 mAh g−1 at the discharge rate of 0.05 C. Especially, LiMn0.5Fe0.5PO4 delivers 100% capacity retention with the reversible capacity of 147 mAh g−1 at the discharge rate of 1 C, and losses only about 23.4% capacity with the discharge rate varying from 0.1 C to 5 C. The variation of energy density predicts that LiMn0.5Fe0.5PO4 shows the potential application for high-power devices.
Wireless sensor networks (WSNs) are being deployed at an escalating rate for various application fields. The ever growing number of application areas requires a diverse set of algorithms with disparate processing needs. WSNs also need to adapt to prevailing energy conditions and processing requirements. The preceding reasons rule out the use of a single fixed design. Instead, a general purpose design that can rapidly be adapted to different conditions and requirements is desired. In lieu of the traditional inflexible wireless sensor node consisting of a separate micro-controller, radio transceiver, sensor array and energy storage, we propose a unified rapidly reconfigurable miniature sensor node, implemented with a transport triggered architecture processor on a low-power Flash FPGA. To our knowledge, this is the first study of its kind. The proposed approach does not solely concentrate on energy efficiency but a high emphasis is also put on the ease of development perspective. Power consumption and silicon area usage comparison based on solutions implemented using our novel rapid design approach for wireless sensor nodes are performed. The comparison is performed between 16-bit fixed point, 16-bit floating point and 32-bit floating point implementations. The implemented processors and algorithms are intended for rolling bearing condition monitoring, but can be fully extended for other applications as well.