batterydata/paper-abstracts huggingface dataset:
There is no consensus for the type(s) of treatment(s) that may be effective or ineffective for psychological nonepileptic seizures (PNES). We provided an open-ended group psychotherapy program to 10 patients with PNES, including a disorder-specific psychoeducation treatment component in the first 10 weeks. Seizure frequency and questionnaire responses were examined pre- and posttreatment in all 7 of 10 individuals who completed the majority of the psychoeducational sessions. Four individuals experienced no change in seizure frequency; in three of these this was due to a cessation of events at treatment initiation. Two individuals experienced a decline; and one, an increase, in seizure frequency. Significant decreases were reported in posttraumatic (P=0.003) and dissociative (P=0.04) symptoms and emotionally based coping mechanisms (P=0.03). There was also a trend toward improved quality of life (P=0.07). Experience/expression of anger remained stable. Psychoeducation may be an effective method of treating PNES and may improve coping strategies and reduce PNES-associated psychopathology in some patients. Additional controlled studies on larger samples are needed.
Numerous studies have reported electronic activity descriptors of oxygen evolution reaction (OER) for oxide catalysts under a single reaction mechanism. However, recent works have revealed that a single mechanism is not at play across oxide chemistries. These works underscore a need to deeply investigate the electronic structure details of active oxide catalysts and how they align with the OER potential, which is critical to understanding the interfacial charge-transfer kinetics that dictate catalytic mechanisms. In this work, we use soft X-ray emission and absorption spectroscopy of perovskites to analyze the partial density of states on an absolute energy scale, from which energetic barriers for electron transfer and surface deprotonation were estimated and correlated with OER activity. Through this lens, we identify that decreasing the solid-state charge-transfer energy of perovskites can change the mechanisms of the OER from electron-transfer-limited to proton–electron-coupled, to proton-transfer-limited reactions. This concept is supported by the analysis of potential energy surfaces for sequential and concerted proton–electron transfer pathways using a Marcus model. Our work highlights the importance of understanding the physical origin of experimental OER activity trends with electronic descriptors and the need to promote surface deprotonation from oxides to discover new catalysts with enhanced activity.
K3[Fe(CN)6] and K4[Fe(CN)6] have been frequently applied in redox flow batteries to achieve sustainable and economical renewable energy storage. However, fundamental knowledge of the redox couple of K3[Fe(CN)6] and K4[Fe(CN)6] regarding their flow battery performance is largely underdeveloped. Herein, we present a comprehensive study on the fundamental properties and electrochemical kinetics of K3[Fe(CN)6] and K4[Fe(CN)6] in aqueous supporting electrolytes at different pH values. Particularly, the charge/discharge cycling stability of the redox couple was evaluated at different pH values using a half-cell flow battery configuration. The battery results unambiguously confirmed that the redox couple functions best at neutral or near neutral conditions. Dramatic capacity decay of the redox couple was observed in a strong alkaline KOH electrolyte (pH =14), which is due to the chemical decomposition associated with the CN- ligand dissociation. The presented study not only advances an in-depth understanding of K3[Fe(CN)6] and K4[Fe(CN)6] regarding their flow battery applications but also highlights the challenge of acid-base side reactions of redox active molecules applied in aqueous acidic/alkaline redox flow batteries.
Transition metal oxide is a promising anode material in lithium-ion battery, however it suffers from poor cycling performance due to its large volume change during charge/discharge process. Herein, we designed and fabricated a yolk-shell Fe3O4 composite nanoparticle with individual Fe3O4 nanoparticle as the yolk and N-coped carbon as the shell by using ionic liquid as the C and N sources. The individual Fe3O4 nanoparticle was firstly covered by a sacrificial SiO2 layer, then coated with N-doped carbon by one-step carbonization with ionic liquid (3-cyanopyridine/H2SO4). After removing the SiO2 layer by NaOH etching, yolk-shell Fe3O4@void@N-doped carbon was obtained. This unique structure would not only afford adequate void to accommodate the large volume change during charge/discharge process, but also improve the structural stability and electrical conductivity. Thus, Fe3O4@void@N-doped carbon showed a high reversible capacity and cycling life of 860mAhg−1 after 500 charge/discharge cycles at a current rate of 1000mAg−1, and excellent rate capacity of 180mAhg−1 even at 7000mAg−1.
Development of sodium-ion battery (SIB) electrode materials currently lags behind electrodes in commercial lithium-ion batteries (LIBs). However, in the long term, development of SIB components is a valuable goal. Their similar, but not identical, chemistries require careful identification of the underlying sodiation mechanism in SIBs. Here, we utilize in situ transmission electron microscopy to explore quite different sodiation behaviors even in similar electrode materials through real-time visualization of microstructure and phase evolution. Upon electrochemical sodiation, single-crystalline ZnO nanowires (sc-ZNWs) are found to undergo a step-by-step electrochemical displacement reaction, forming crystalline NaZn13 nanograins dispersed in a Na2O matrix. This process is characterized by a slowly propagating reaction front and the formation of heterogeneous interfaces inside the ZNWs due to non-uniform sodiation amorphization. In contrast, poly-crystalline ZNWs (pc-ZNWs) exhibited an ultrafast sodiation process, which can partly be ascribed to the availability of unobstructed ionic transport pathways among ZnO nanograins. Thus the reaction front and heterogeneous interfaces disappear. The in situ TEM results, supported by calculation of the ion diffusion coefficient, provide breakthrough insights into the dependence of ion diffusion kinetics on crystallization form. This points toward a goal of optimizing the microstructure of electrode materials in order to develop high performance SIBs.
The electrolyte of a solid oxide fuel cell (SOFC) is an O2−-ion conductor. The anode must oxidize the fuel with O2− ions received from the electrolyte and it must deliver electrons of the fuel chemisorption reaction to a current collector. Cells operating on H2 and CO generally use a porous Ni/electrolyte cermet that supports a thin, dense electrolyte. Ni acts as both the electronic conductor and the catalyst for splitting the H2 bond; the oxidation of H2 to H2O occurs at the Ni/electrolyte/H2 triple-phase boundary (TPB). The CO is oxidized at the oxide component of the cermet, which may be the electrolyte, yttria-stabilized zirconia, or a mixed oxide-ion/electron conductor (MIEC). The MIEC is commonly a Gd-doped ceria. The design and fabrication of these anodes are evaluated. Use of natural gas as the fuel requires another strategy, and MIECs are being explored for this application. The several constraints on these MIECs are outlined, and preliminary results of this on-going investigation are reviewed.
Tris(trimethylsilyl) phosphite (P(OSi(CH3)3)3) is a multifunctional electrolyte additive for scavenging HF and forming a cathode electrolyte interphase (CEI). Systematic analysis of the HF reaction pathways and redox potentials of P(OSi(CH3)3)3, OP(OSi(CH3)3)3, P(OSiF3)3, and OP(OSiF3)3, and their reaction products, using ab initio calculations allowed us to elucidate the operating mechanism of P(OSi(CH3)3)3 and verify the rules that determine its HF reaction pathways and electrochemical stability. While OSi cleavage is the predominant HF scavenging pathway for P(OSi(CH3)3)3, OP cleavage is stabilized by replacing CH3 with an electron-withdrawing group. Thus, P(OSiF3)3 scavenges HF mainly through OP cleavage to produce PF3, which has high oxidation stability. However, the OSi cleavage pathway produces P(OSi(CH3)3)2OH, P(OSi(CH3)3) (OH)2, and P(OH)3 sequentially, along with Si(CH3)3F. These PO3 systems, which are oxidized earlier than carbonate solutions and form tightly bonded units following oxidation, act as seed units for compact CEI growth. Moreover, the HF scavenging ability of PO3 systems is maintained during oxidation until all OSi bonds are broken. As a strategy for developing additives with enhanced functionality, modifying P(OSi(CH3)3)3 by replacing CH3 with an electron-donating group to exclusively utilize the OSi cleavage pathway for HF scavenging is recommended.
The carbon-microelectromechanical systems (C-MEMS) microfabrication process offers a promising method for fabricating three-dimensional (3D) battery architectures. In the current study, this approach was extended to the fabrication of positive electrode arrays and their assembly in a 3D lithium-ion microbattery. The positive electrode array was fabricated by electrochemical deposition of dodecylbenzenesulfonate-doped polypyrrole (PPYDBS) on an array of carbon rods. Electrochemical measurements show that the electrodeposited PPYDBS electrode array reversibly intercalates lithium with better gravimetric capacity than that of 2D electrodeposited films. The prototype carbon/PPYDBS 3D battery was based on an interdigitated electrode array configuration. It functioned as a secondary battery but the performance was limited because of electrical shorting. These initial results with the 3D interdigitated battery help to identify the needs associated with different electrode fabrication approaches and specific 3D designs.
The last few decades have seen tremendous explosion of activity in the area of Nanoscience and Nanotechnology. Semiconducting metal oxides and their composites form an important class of materials for the envisaged cutting edge applications. Several approaches have been attempted by researchers to prepare nanocrystalline metal oxides, study the material properties and explore their feasibility for a variety of applications. In this review, the highlights of authors’ research efforts vis-à-vis the global state of nanomaterial research is discussed briefly. A comprehensive outlook on some of the important metal oxides, the various strategies practiced to synthesize them, along with a bird’s eye view of the results, important breakthroughs and achievements in the last decade are briefly discussed.
To investigate the relationship between pore structure and specific capacitance of electric double layer capacitors with non-aqueous electrolytes, phenol resin based carbon spheres were modified by oxidation in dry air, giving a wide range of pore structure. Surface area due to the presence of different pores was characterized through α s plots of adsorption isotherms of N2 gas at 77K as microporous surface area (S micro.) due to micropores and external surface area (S ext.) mainly due to the mesopores. A simple model can be presented by recognizing the different contributions of S micro. and S ext. in forming electric-double layers. The capacitance per unit external surface area was larger by one order of magnitude than that per unit surface area of micropores (0.187F/m2 versus 0.017F/m2 at charge–discharge current of 4mA/g), revealing greater contribution of external surface to specific capacitance for electric-double layers than surface of micropores. With the increase in charge–discharge current to 40mA/g, the relative contribution of external surface became more significant, which was supposed to be due to large sizes of electrolyte ions, Et3MeN+ and BF4 −.
In this paper a two level hierarchical methodology is presented for the integral design of hybrid power generation systems based on alternative renewable energy (ARE) systems using the net energy concept and considering technical, economical, societal as well as environmental aspects. Results are presented for the design of a small-scale hybrid renewable energy system using the proposed methodology in Margarita Island, Venezuela. The proposed methodology applies the integrated analytical hierarchy process (AHP) methodology to the selection of the best hybrid renewable energy system using the concept of net energy and is divided in two phases: a classic optimization process using levelized costs minimization and an AHP implementation for decision making problems. Under this methodology technical–economical aspects are considered as quantitative parameters, while social–environmental aspects depend largely on the criteria of the system planning engineers and future users of the system. Technical–economical aspects are considered using specialized software, used to optimize and compute the best configuration of an ARE project. Social–economical aspects are defined as a series of parameters that should be considered by the planning team, a meeting of experts or a community consensus on the project site. Several diesel price scenarios (low, intermediate and high) are considered. The results show the importance of the proposed tools for decision making problems.
Renewable power (photovoltaic, solar thermal or wind) is inherently intermittent and fluctuating. If renewable power has to become a major source of base-load dispatchable power, electricity storage systems of multi-MW capacity and multi-hours duration are indispensable. An overview of the advanced energy storage systems to store electrical energy generated by renewable energy sources is presented along with climatic conditions and supply demand situation of power in Saudi Arabia. Based on the review, battery features needed for the storage of electricity generated from renewable energy sources are: low cost, high efficiency, long cycle life, mature technology, withstand high ambient temperatures, large power and energy capacities and environmentally benign. Although there are various commercially available electrical energy storage systems (EESS), no single storage system meets all the requirements for an ideal EESS. Each EESS has a suitable application range.
Neutron depth profiling (NDP) is a nondestructive technique that has been applied to characterize the lithium concentration in the electrode materials of Li-ion batteries as a function of depth. NDP measurements have been traditionally performed ex-situ, under vacuum of the order of 10−6 Torr to avoid any change in the residual energy of the charged particles as they emerge from the sample surface. In this work, we describe the design of the NDP measurement facility that allows for conducting tests at variable pressure conditions, through an inert gas atmosphere. This study enhances the ability of the conventional NDP instrument to measure lithium concentration of air-sensitive materials without exposure to atmospheric conditions and under inert gas atmosphere. Furthermore, it provides the opportunity to conduct in-situ NDP on Li-ion cells using liquid electrolytes that would otherwise evaporate at high vacuum conditions.
In this article, artificial neural network (ANN) is adopted to predict photovoltaic (PV) panel behaviors under realistic weather conditions. ANN results are compared with analytical four and five parameter models of PV module. The inputs of the models are the daily total irradiation, air temperature and module voltage, while the outputs are the current and power generated by the panel. Analytical models of PV modules, based on the manufacturer datasheet values, are simulated through Matlab/Simulink environment. Multilayer perceptron is used to predict the operating current and power of the PV module. The best network configuration to predict panel current had a 3–7–4–1 topology. So, this two hidden layer topology was selected as the best model for predicting panel current with similar conditions. Results obtained from the PV module simulation and the optimal ANN model has been validated experimentally. Results showed that ANN model provide a better prediction of the current and power of the PV module than the analytical models. The coefficient of determination (R 2), mean square error (MSE) and the mean absolute percentage error (MAPE) values for the optimal ANN model were 0.971, 0.002 and 0.107, respectively. A comparative study among ANN and analytical models was also carried out. Among the analytical models, the five-parameter model, with MAPE=0.112, MSE=0.0026 and R 2 =0.919, gave better prediction than the four-parameter model (with MAPE=0.152, MSE=0.0052 and R 2 =0.905). Overall, the 3–7–4–1 ANN model outperformed four-parameter model, and was marginally better than the five-parameter model.
Background The purpose of this study was to assess the burst strength and stiffness of heavy weight (HW), mid-weight (MW), and light weight (LW) polypropylene mesh pre-implantation and 5 months post-implantation in a porcine ventral hernia model. Materials and methods HW (95 g/cm2), MW (45 g/cm2), and LW (28 g/cm2) polypropylene were tested as dry samples (n = 8/mesh) before implantation using a stamp strain machine. Three weeks after creating four hernia defects in each mini-pig (n = 18), the polypropylene meshes (8 × 10 cm; 24/mesh type) were implanted in the preperitoneal space, ensuring 2 cm overlap circumferentially. At 5 months, the mesh was harvested en bloc with the abdominal wall. Testing of burst strength and stiffness was repeated on the ex vivo specimens. Results After implantation in the pig for 5 months, the mean burst strength and stiffness of HW and MW meshes remains the same. LW mesh with an absorbable monofilament in its weave has significant reductions in mean burst strength (P = 0.01) and mean stiffness (P < 0.0001). The burst strength for all meshes tested was much higher than measured for the abdominal wall fascia alone. The degree of shrinkage of the various weight meshes did not differ. Conclusion A reduction in mean burst strength and stiffness occurs after 5 months implantation of LW polypropylene mesh with an absorbable monofilament. All meshes exhibited burst strengths that were much greater than the burst strength of the abdominal wall fascia alone. After tissue incorporation, the LW polypropylene mesh maintains mean burst strength comparable to MW polypropylene mesh, while becoming less stiff than HW mesh. Long-term, this may contribute to more physiological abdominal wall compliance after LW polypropylene mesh implantation.
Importance analysis is conducted for an off-grid wind power generation system, due to the lack of similar studies particularly on renewable energy systems. Birnbaum importance (BI) and criticality importance (CI) evaluation methods are used to evaluate the importance level of each component and investigate the impact of associated factors. Results reveal that 1) an increase in failure rate of component would cause a corresponding growth of the impact on system reliability, no matter which connection mode is selected; 2) connection mode plays a more important role than failure rate; 3) importance level would be increased with a decrease in the number of identical components connected in parallel; 4) a longer operational time would cause a higher probability of system failure. The implication in this study could drive a transfer of our major concern from the traditional ׳system analysis׳ to the current ׳component analysis׳. This transfer could help to seek more theoretical bases in support of system design, process optimization, probability safety assessment, reliability analysis, etc.
The purpose of this study was to examine the effects of acute l-arginine (l-arg) supplementation on peripheral vasodilatation and muscle performance in older women.
The distribution of lithium in V2O5/V lower oxide duplex thin films prepared by thermal oxidation of V metal was analysed by XPS and ToF-SIMS after intercalation at 2.8V versus Li/Li+ and de-intercalation at 3.8V following cycling between 3.8 and 2.8V in 1M LiClO4-PC. XPS analysis of the intercalated thin film evidenced a partial reduction (43at.% V4+) of the V2O5 surface, the modification of its electronic structure and the presence of Li, consistent with the formation of the δ-Li x V2O5 (0.9≤ x ≤1) phase. The Li in-depth distribution measured by ToF-SIMS shows a maximum in the outer layer of V2O5, but Li is also found at the oxide film/metal substrate interface indicating its diffusion across the inner layer of V lower oxides. The analyses performed after de-intercalation on the samples cycled 12, 120 and 300 times reveal the effect of aging on the trapping of lithium. A significant reduction (17–22at.% V4+) of the V2O5 surface was measured after 300 cycles. The Li in-depth distribution shows a maximum at the interface between the outer layer of V2O5 and the inner layer of lower oxides. Aging favours the accumulation of lithium at this interface with a resulting enlarged distribution enriching the sub-surface of the outer layer of V2O5 and the inner layer of lower oxides after 300 cycles. Lithium is also found, but in smaller quantities, at the oxide film/metal substrate interface. Measurements performed in the non-electrochemically treated surface areas of the de-intercalated samples revealed the same type of modifications, evidencing the diffusion of lithium along the interfaces where it is trapped.
Lithium nickel manganese oxide of LiNi1/2Mn1/2O2, which is a one-to-one mixture of LiNiO2 and LiMnO2 in its chemical composition, has been prepared by an improved processing method. Cycle tests of a lithium cell with LiNi1/2Mn1/2O2 operated in voltages of 2.5–4.5V shows about 200mAhg−1 of rechargeable capacity without noticeable loss during 30 cycles. The thermal behavior of fully charged LiNi1/2Mn1/2O2 is also examined by differential scanning calorimetry (DSC) and shows that the exothermic reaction of □0.89Li0.11Ni1/2Mn1/2O2 (fully charged state under this experimental condition) is milder than that of □NiO2 or □Mn2O4. The results on rate-capability tests of a Li/LiNi1/2Mn1/2O2 cell show that 85% of discharge capacity observed at low rate discharge can be stored and delivered at 1h rate at present.
Objective Assess individual-subject long-term and within-day variability of a combined behavioral and EEG test of working memory. Methods EEGs were recorded from 16 adults performing n-back working memory tasks, with 10 tested in morning and afternoon sessions over several years. Participants were also tested after ingesting non-prescription medications or recreational substances. Performance and EEG measures were analyzed to derive an Overall score and three constituent sub-scores characterizing changes in performance, cortical activation, and alertness from each individual’s baseline. Long-term and within-day variability were determined for each score; medication effects were assessed by reference to each individual’s normal day-to-day variability. Results Over the several year period, the mean Overall score and sub-scores were approximately zero with standard deviations less than one. Overall scores were lower and their variability higher in afternoon relative to morning sessions. At the group level, alcohol, diphenhydramine and marijuana produced significant effects, but there were large individual differences. Conclusions Objective working memory measures incorporating performance and EEG are stable over time and sensitive at the level of individual subjects to interventions that affect neurocognitive function. Significance With further research these measures may be suitable for use in individualized medical care by providing a sensitive assessment of incipient illness and response to treatment.