batterydata/paper-abstracts huggingface dataset:
The electrode materials with structure stability and binder-free are urgently required for improving the electrochemical performance of lithium-ion batteries. In this work, interconnected α-Fe2O3 nanosheet arrays directly grown on Ti foil were fabricated via a facile galvanostatic electrodeposition method followed by thermal treatment. The as-prepared α-Fe2O3 has an open network structure constituted of interconnected nanosheets and can be directly used as integrated electrodes for lithium-ion batteries. The α-Fe2O3 nanosheet arrays exhibit a high reversible capacity of 986.3mAhg−1 at a current density of 100mAg−1. Moreover, a reversible capacity of ca. 425.9mAhg−1 is achieved even at a superhigh current density of 10Ag−1, which is higher than the theoretical capacity of commercially used graphite. The excellent performance could be attributed to the efficient electron transport, the large electrode/electrolyte interfaces and the good accommodations for volume expansion from the interconnected nanosheet arrays structure.
Vinyl laurate is a potential residual monomer in chewing gum base formulated with polyvinyl acetate vinyl laurate copolymer (PVAcVL). The genotoxic potential of vinyl laurate was examined in a battery of in vitro and in vivo genotoxicity tests. Vinyl laurate was not mutagenic in Ames tests. In addition, it was not mutagenic in the HPRT mutation assay in L5178Y cells. An in vitro mammalian chromosome aberration assay performed in CHO cells was equivocal. Vinyl laurate and/or its metabolites were not clastogenic in the mouse bone marrow micronucleus test. Kinetic data indicate that VL is metabolised to acetaldehyde and lauric acid. Both metabolites are well known and have been studied previously. Model calculations show, that any exposure to acetaldehyde from the consumption of PVAcVL containing chewing gum will remain far below levels of acetaldehyde exposure from food in which acetaldehyde occurs naturally. Direct exposure to VL will primarily be at the site of entry. The lack of toxicity in a 90-day repeated dose toxicity test, performed with VL doses up to approximately 3000 times higher than the maximal VL intake from the consumption of a typical piece of chewing gum, demonstrates a high safety margin.
Background Left ventricular assist devices (LVADs) provide a bridge to recovery or heart transplantation but require serial assessment. Echocardiographic approaches may be limited by device artifact and acoustic window. Cardiovascular computed tomography (CCT) may provide improved non-invasive imaging of LVADs. We evaluated the diagnostic findings and clinical impact of CCT for non-invasive assessment of patients with LVADs. Methods CCT examinations performed between 2005 and 2008 in patients with LVADs were identified. Acquisitions were completed on the identical 64-detector-row scanner with intravenous contrast administration. Electrocardiographic gating was used in patients with pulsatile devices, and peripheral pulse gating was used in patients with continuous-flow devices. Comparison was made between CCT results and 30-day outcomes, including echocardiographic and intraoperative findings. Results We reviewed 32 CCT examinations from 28 patients. Indications included evaluation of low cardiac output symptoms, assessment of cannula position, low flow reading on the LVAD, and surgical planning. CCT identified critical findings in 6 patients, including thrombosis and inlet cannula malposition, all confirmed intraoperatively. CCT missed 1 case of intra-LVAD thrombus. Using intraoperative findings as the gold standard, CCT's sensitivity was 85% and specificity was 100%. Echocardiographic LVAD evaluation did not correlate with findings on CCT (κ = −0.29, 95% confidence interval, −0.73 to 0.13). Conclusions This preliminary observational cohort study indicates that non-invasive imaging using CCT of LVADs is feasible and accurate. CCT warrants consideration in the initial evaluation of symptomatic patients with LVADs.
Metabolic bioactivation of polycyclic aromatic hydrocarbons, such as the environmental procarcinogen benzo[a]pyrene, is catalyzed by a cytochrome P450 monooxygenase encoded by the substrate-inducible Cyp1a1 gene. Cyp1a1 induction requires trans-activation by the heterodimeric transcriptional complex formed by the liganded Ah receptor (AHR) and its partner, ARNT. Previously, we showed that constitutively bound HDAC1 dissociates from Cyp1a1 promoter chromatin after ligand-mediated induction, concomitantly with the recruitment of AHR/ARNT complexes and p300. Here, we investigated the hypothesis that HDAC1 binding maintains the Cyp1a1 gene in a silenced state in uninduced cells. We find that Cyp1a1 induction by the AHR/ARNT is associated with modification of specific chromatin marks, including hyperacetylation of histone H3K14 and H4K16, trimethylation of histone H3K4, and phosphorylation of H3S10. HDAC1 and DNMT1 form complexes on the Cyp1a1 promoter of uninduced cells but HDAC1 inhibition alone is not sufficient to induce Cyp1a1 expression, although it allows for the hyperacetylation of H3K14 and H4K16 to levels similar to those found in B[a]P-induced cells. These results show that by blocking the modification of histone marks, HDAC1 plays a central role in Cyp1a1 expression and that its removal is a necessary but not sufficient condition for Cyp1a1 induction, underscoring the requirement for a concerted series of chromatin-remodeling events to complete the initial steps of gene trans-activation by the Ah receptor.
Wood-derived biochar is an attractive material for supercapcitor electrodes due to its natural hierarchical structure. To improve the conductivity of biochar, graphene oxide is electrophoretically deposited, followed by electrochemical reduction. The conductivity can be controlled by either changing the amount of reduced graphene oxide loading by using different concentrations of graphene oxide suspension or by reaching different reduction states by varying the electrochemical reduction potential. The pore structure is also investigated to evaluate the microstructure effect on the material’s capacitive behavior. A specific capacitance of 167 F g−1 is achieved after reduced graphene oxide deposition, which is 4.3 times higher than that of biochar without reduced graphene oxide. The reduced graphene oxide-modified biochar electrodes show a high rate capability retention of approximately 90% with current densities from 0.5 to 3.0 A g−1. Additionally, no degradation is observed after 10,000 charging–recharging cycles under 5.0 A g−1.
Biofuels are liquid or gaseous fuels that are predominantly produced from biomass for transport sector applications. As biofuels are renewable, sustainable, carbon neutral and environmentally benign, they have been proposed as promising alternative fuels for gasoline and diesel engines. This paper reviews state-of-the-art application of the supercritical fluid (SCF) technique in biofuels production that includes biodiesel from vegetable oils via the transesterification process, bio-hydrogen from the gasification and bio-oil from the liquefaction of biomass, with biodiesel production as the main focus. The global biofuel situation and biofuel economics are also reviewed. The SCF has been shown to be a promising technique for future large-scale biofuel production, especially for biodiesel production from waster oil and fat. Compared with conventional biofuel production methods, the SCF technology possesses a number of advantages that includes fast kinetics, high fuel production rate, ease of continuous operation and elimination of the necessity of catalysts. The harsh operation environment, i.e. the high temperature and high pressure, and its request on the materials and associated cost are the main concerns for its wide application.
Tin oxides (SnO2) are promising anode material candidate for next-generation lithium-ion batteries due to their high capacity, low cost, high abundance, and low toxicity. However, the practical use of SnO2 anodes is currently limited by their large volume changes during cycling. Severe volume changes of SnO2 anodes lead to intense pulverization and loss of electrical contact between the active material and carbon conductor. Herein, we introduce binder-free SnO2-electrodeposited carbon nanofibers (CNF@SnO2) and SnO2-electrodeposited porous carbon nanofibers (PCNF@SnO2) composites that can maintain their structural stability during repeated charge–discharge cycling. Results indicated that the amount of the electrodeposited SnO2 nanoparticles and the capacity of the resultant composites were successfully enhanced by using a porous nanofiber structure. Both CNF@SnO2 and PCNF@SnO2 composites were also coated with amorphous carbon layers by chemical vapor deposition to further improve the structural stability. Electrochemical performance results demonstrated that the combination of porous nanofiber structure and CVD amorphous coating led to a novel carbon-coated PCNF@SnO2 composite anode with high capacity retention of 78% and large coulombic efficiency of 99.8% at the 100th cycle.
Combination of transition metal oxides and graphene sheets (GS) is an effective strategy to improve the electrochemical performance of transition metal oxides. In the present work, we report a facile and simple hydrothermal method to synthesize the nanocomposite of SnO2 dodecahedral nanocrystals (DNCs) anchored on GS as an advanced anode material for high-performance lithium-ion batteries (LIBs). Benefiting from the unique properties of graphene, the SnO2 DNCs-GS nanocomposite exhibits significant enhanced Li-battery performance compared with the pure SnO2 DNCs. The initial discharge and charge capacities of the SnO2 DNC-GS electrode are 1653.2 and 1085.6mAhg−1, respectively. After 50 cycles, it still exhibits a high discharge capacity of 783.9mAhg−1 at the current density of 200mAg−1. Remarkably, the discharge capacity of the SnO2 DNCs-GS can still retain as high as 730.3mAhg−1 at a high rate of 5Ag−1, indicating good rate capability. The electrochemical results suggest the SnO2 DNCs-GS nanocomposite would be a promising candidate as anode material in energy storage applications for high-performance LIBs. Our study also highlights the importance of rational design and synthesis of graphene-based materials for high-performance LIBs.
Sn-based materials are one promising high-capacity anode material for lithium-ion batteries. The practical application of Sn-based materials is generally restricted by their significant capacity fading due to the volume expansion and structural changes during Sn alloying/dealloying process. In this work, Sn-SnO2 hybrid nanoclusters are embedded into carbon nanotube network, forming a Sn-SnO2@CNT composite. The Sn-SnO2 nanoclusters are consisted of interconnected Sn and SnO2 nanocrystals, in which SnO2 forms a beneficial environment for the alloying/dealloying of Sn. The ultrafine particle size of SnO2 (<10 nm) also allows a highly reversible conversion reaction, contributing to high overall capacities. The Sn-SnO2 nanoclusters are uniformly dispersed in CNT matrix, therefore providing abundant active sites for Li-ion storage. The CNT matrix functions in improving electrical conductivity, preventing Sn aggregation, and accommodating Sn volume change in prolonged cycles. As a result, the hybrid Sn-SnO2@CNT electrode shows excellent rate capability (1059 mAh g−1 at 1 A g−1 and 960 mAh g−1 at 5 A g−1, corresponding to 0.53 mAh cm−2 at 0.5 mA cm−2 and 0.48 mAh cm−2 at 2.5 mA cm−2) and outstanding cycling stability (86% capacity retention after 1000 cycles at 0.5 A g−1), making it an promising anode material for high-performance lithium-ion batteries.
We present high quality WX2 (X=S, Se) single crystals synthesized via an improved chemical vapor transport technique. Morphological and structural characteristics of the as-grown layered single crystals were analyzed using SEM, TEM, XPS, Raman spectroscopy, XRD and UV visible spectroscopy characterization techniques. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge-discharge analysis reveal the insights for WX2 single crystals to be used an as excellent material for electrochemical supercapacitors. Notably the obtained supercapacitor electrodes show excellent cycle stability and high capacitance retention of 80 and 99% for WS2 and WSe2 respectively after 20,000 cycles, suggesting their high potential in electrochemical energy storage applications.
Uninterruptible Power Supplies (UPS) have reached a mature level by providing clean and uninterruptible power to the sensitive loads in all grid conditions. Generally UPS system provides regulated sinusoidal output voltage, with low total harmonics distortion (THD), and high input power factor irrespective of the changes in the grid voltage. This paper provides comprehensive review of UPS topologies, circuit configurations, and different control techniques used in the UPS system. A comparison based on the performance, size, cost, and efficiency of the system is presented. Different hybrid energy source UPS system and new generation UPS system for smart grid and micro-grid has been explained. Finally the paper describes performance evaluation of UPS system and explains different aspects that are to be considered for choosing a suitable UPS system by the user.
Phenolic ethers are useful commercial entities which have been traditionally produced via polluting routes that could be replaced by benign catalytic processes. In the current work, O-methylation of mono-, di- and tri-hydroxy benzenes (phenolics), namely, phenol, catechol and pyrogallol, has been studied with dimethyl carbonate (DMC) as the etherification agent cum solvent in the presence of a phosphonium ionic liquid as catalyst. The co-products methanol and CO2 could be recycled to make DMC. The catalyst is recycled and thus the overall process is a green process. Ionic liquids possess many useful attributes and can be used as solvents and multi-functional catalysts, and some are amenable to recycling and reuse using clever strategies. Two different types of phosphonium-based ionic liquids were used – one group containing the trihexyl (tetradecyl) cation such as trihexyl (tetradecyl) phosphonium chloride (PC), trihexyl (tetradecyl) phosphonium bromide (PB), trihexyl (tetradecyl) phosphonium decanoate (PD), trihexyl (tetradecyl) phosphonium hexafluoro phosphate (HFP), and another symmetric reference containing the tetrabutyl phosphonium cation (tetrabutyl phosphonium bromide (TBPB)) – and were evaluated in the O-methylation of phenol, catechol and pyrogallol with DMC to the corresponding ethers. Depending on the number of hydroxyl groups on the benzene ring, different mono- and poly-ethers could be produced by using suitable process conditions such as molar ratio, catalyst, temperature and time. All of these intermediate and final ethers have different applications. Trihexyl (tetradecyl) phosphonium bromide (PB) was the best catalyst. Effects of various parameters on the rate of reaction, conversion and yield were studied including speed of agitation, catalyst concentration and reusability, reactant concentration and temperature. The best operating conditions were 200 °C, a 1:6 mole ratio of reactant to DMC, and trihexyl (tetradecyl) phosphonium bromide (PB) as catalyst. A reaction mechanism is proposed and discussed to deduce the kinetics.
Mobile phones have grown rapidly using today's wireless technology thereby providing a new dimension to simplify daily routine jobs by users. Mobile phone's applications have a great impact on the way of faster and more effective to convey information. In contrast, mobile phones could harm its users. This paper explored detrimental effects of mobile phones on energy consumption, electromagnetic radiofrequency radiation, environment, health and accidents. The effect of mobile phone's energy consumption can be considered during energy spend for its production and use. The electromagnetic radiofrequency radiation (EMRF) may cause adverse health effects on human. The raw materials which are used to manufacture for mobile phones may cause the severe environmental impacts due to their levels of toxicity. The health hazards are correlated with high-toxic substances released from the mobile phones and its addiction through a prolonged use. Mobile phone usage while driving can cause road traffic collisions and motor vehicle crashes. Furthermore, sustainable perspectives have been suggested as a way to overcoming these detrimental effects of mobile phones.
This work applied a newly developed low-cost sensing (LCS) device (AS-LUNG-P) and a certified medical LCS device (Rooti RX) to assessing PM2.5 impacts on heart rate variability (HRV) and determining important exposure sources, with less inconvenience to subjects.
Introduction Benign epilepsy with centrotemporal spikes (BECTS) is a common epilepsy syndrome in childhood. Besides the occurrence of seizures, mild cognitive impairments and behavioral problems affecting language skills, spatial perception, memory, executive function, and academic achievement might be present. There is no international consensus about the decision whether or not to treat affected children. The influence of treatment on cognitive functions is debated. Methods Patients diagnosed with BECTS were assessed in short term auditory memory, long-term verbal memory, intelligence and behavior using the “number recall” test from the Kaufman assessment battery for children, the “verbal learning memory test”, the “culture free intelligence test” and the “child behavior checklist” prior to a randomized controlled antiepileptic therapy and after a treatment period of 6 months with either sulthiame or levetiracetam. Results 43 of 44 randomized patients were analyzed. One patient had to be excluded due to protocol violation. Patients who completed the study showed a non-significant improvement in parent-reported behavioral problems under therapy. Cognitive skills were not affected. Conclusion The present data suggest that antiepileptic drug treatment of children with BECTS with either sulthiame or levetiracetam does not affect cognitive performance. Behavior improved in a subset of patients though not reaching statistical significance.
This research focused on the transition of biofuel cell technology to rechargeable biobatteries. The bioanode compartment of the biobattery consisted of NAD-dependent alcohol dehydrogenase (ADH) immobilized into a carbon composite paste with butyl-3-methylimidazolium chloride (BMIMCl) ionic liquid serving as the electrolyte. Ferrocene was added to shuttle electrons to/from the electrode surface/current collector. The bioanode catalyzed the oxidation of ethanol to acetaldehyde in discharge mode. This bioanode was coupled to a cathode that consisted of Prussian Blue in a carbon composite paste with Nafion 212 acting as the separator between the two compartments. The biobattery can be fabricated in a charged mode with ethanol and have an open circuit potential of 0.8V in the original state prior to charging or in the discharged mode with acetaldehyde and have an open circuit potential of 0.05V. After charging it has an open circuit potential of 1.2V and a maximum power density of 13.0μWcm−3 and a maximum current density of 35.0μAcm−3, respectively. The stability and efficiency of the biobattery were studied by cycling continuously at a discharging current of 0.4mA and the results obtained showed reasonable stability over 50 cycles. This is a new type of secondary battery inspired by the metabolic processes of the living cell, which is an effective energy conversion system.
LiCoO2 thin films are receiving attention as positive electrodes (cathodes) for thin-film microbatteries. In this study, LiCoO2 thin films are fabricated by a sol–gel spin-coating method and a post-annealing process. The thermal decomposition behaviour of the precursor is investigated by thermogravimetry/differential thermal analysis TG/DTA and mass spectroscopy. The crystallinity, microstructure and electrochemical properties of the final films are also studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic charge-discharge cycling tests. Films heat-treated under appropriate conditions exhibit high capacity and good crystallinity and are therefore considered to be candidates as cathodes for thin-film microbatteries.
A locally patented, universal photoelectric power supply from Beijing Solar Photoelectric Centre can be used with most cellphone brands. The price is negotiable, and the packaging is according to customers' requirements.
Recent studies have proposed that difficulty with accessing the lexical–semantic memory store may underpin some of the specific linguistic problems associated with formal thought disorder (FTD). We examined the consistency of name retrieval as an indicator of the ability to access lexical–semantic knowledge in patients with and without marked FTD to see if problems are specific to the former or common to schizophrenic patients in general. A graded naming test was administered on two separate occasions 8–16 weeks apart to 48 participants in three groups: 16 schizophrenic patients with high ratings of FTD, 16 schizophrenic patients with low ratings of FTD and 16 healthy controls. We compared the groups for naming consistency across time and the relationship between naming consistency and specific symptoms of FTD. Both patient groups had impaired naming and this was significantly greater in high than low FTD patients. The high FTD patients showed a profile that differed from both low FTD patients and healthy controls insofar as their naming was inconsistent across time, characteristic of an access disorder. Specifically, the FTD symptoms of derailment, tangentality and incoherence were related to the ability to access the lexical–semantic store. In conclusion, most patients with schizophrenia show an impaired semantic memory store. Nevertheless, FTD is associated with additional lexical–semantic difficulties that are quantitatively different to those seen in patients without FTD, and which may reflect disorganized semantic access.
Additives to lead–acid battery active materials and components are categorized as physical and chemical attribute additives. Separators are equally divided into two classes, those that have inner skeletal structures, commonly made of mixtures of polymers and precipitated silica, and those that are made of loose fibers. Separator additives are also briefly discussed. Both physical and chemical impacts of active material additives on separators are considered. With the noted exception of negative plate expanders, very little interaction has been reported thus far between active material additives and separators. This question should be further investigated in the light of the growing importance of additives in improving the performance of the lead–acid battery.
Cyclic and chronoamperometric electrochemical quartz crystal microbalance measurements are reported for polyaniline deposited on Au and immersed in aqueous solution of 1 mol dm−3 H2SO4. The results of piezoelectric microgravimetry indicate a mixed cationic and anionic ion transport. Although most of the frequency change after application of a potential step occurs within 1 s — attesting that even the anion transport is fast — a slow, logarithmic type relaxation can also be observed. The duration of the continuous mass change may be longer than 30 min, especially during a transition from reduced state to a medium oxidized state or vice versa. The change of the film resistance measured in situ shows a similar behaviour. The marked hysteresis effect between oxidation and reduction sequences may be explained a fast stabilization process including the planarization of the polymer and intermolecular coupling at higher charging level as well as a slower transformation at lower degree of oxidation. The effect of temperature is very small on the processes responsible for the relaxation phenomena and the hysteresis effect, consequently the enhancement of the chain motion may play a minor role, only.