batterydata/paper-abstracts huggingface dataset:
Developing high-performance non-precious metal electrocatalysts for oxygen reduction reaction (ORR) is crucial for the commercialization of fuel cells and metal-air batteries. However, doped carbon-based materials only show good ORR activity in alkaline medium, and become less effective in acidic environment. We believe that an appropriate combination of both ionic and electronic transport path, and well dopant distribution of doped carbon-based materials would help to realize high ORR performance under both acidic and alkaline conditions. Accordingly, a nitrogen and sulfur co-doped carbon framework with hierarchical through-hole structure is fabricated by morphology-controlled solid-state pyrolysis of poly(aniline-co-2-aminothiophenol) foam. The uniform high concentrations of nitrogen and sulfur, high intrinsic conductivity, and integrated three dimensional ionic and electronic transfer passageways of the 3D porous structure lead to synergistic effects in catalyzing ORR. As a result, the limiting current density of the carbonized poly(aniline-co-2-aminothiophenol) foam is equivalent to commercial Pt/C in acidic environment, and twice the latter in alkaline medium.
The single-crystalline LiMn2O4 nanorods were successfully synthesized by a simple, low-cost and eco-friendly approach in which the γ-MnOOH nanorods were prepared through a facile hydrothermal process, in which KMnO4 was reduced by anhydrous alcohol (CH3CH2OH) without adding any template reagent or additional surfactant. The crystal structures and morphologies of synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. The results showed that the γ-MnOOH nanorods had high crystallinity and well-shaped morphology with an average diameter of 200nm and an average length of 12μm. For the resulting LiMn2O4 nanorods, the electrochemical properties were investigated by galvanostatic charge-discharge test, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). For the optimal LiMn2O4 nanorods, the initial discharge capacity was 123.5mAhg−1 and remained 110.2mAhg−1 after 100 cycles at 1.0C in the voltage range of 3.20∼4.35V. Moreover, the optimal LiMn2O4 nanorods can present superior rate performance, especially the capacity recovery performance as the charge-discharge rate restores to 0.1C from 5.0C. Such excellent electrochemical performance could make them to be the promising cathode material for high performance lithium-ion batteries.
The effect of nickel and sulfur substitution for manganese and oxygen on the structure and electrochemical properties of the LiNi0.5Mn1.5O4−x S x is examined. The LiNi0.5Mn1.5O4−x S x (x =0 and 0.05) compounds are successfully synthesized at 500 and 800°C by co-precipitation using the metal carbonate (Ni0.5Mn1.5)CO3 as a precursor. The resulting powder with sulfur doping exhibits different morphology from a Ni-only doped spinel in terms of particle size and surface texture. The LiNi0.5Mn1.5O4−x S x (x =0 and 0.05) powders are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and galvanostatic charge–discharge cycling. The nickel- and sulfur-doped spinel displays excellent capacity retention and rate capability in the 3-V region, compared with Ni-only doped spinel material.
In NiMH battery leaching, rare earth element (REE) precipitation from sulfate media is often reported as being a result of increasing pH of the pregnant leach solution (PLS). Here we demonstrate that this precipitation is a phenomenon that depends on both Na+ and SO4 2− concentrations and not solely on pH. A two-stage leaching for industrially crushed NiMH waste is performed: The first stage consists of H2SO4 leaching (2 M H2SO4, L/S = 10.4, V = 104 ml, T = 30 °C) and the second stage of H2O leaching (V = 100 ml, T = 25 °C). Moreover, precipitation experiments are separately performed as a function of added Na2SO4 and H2SO4. During the precipitation, higher than stoichiometric quantities of Na to REE are utilized and this increase in both precipitation reagent concentrations results in an improved double sulfate precipitation efficiency. The best REE precipitation efficiencies (98–99%) – achieved by increasing concentrations of H2SO4 and Na2SO4 by 1.59 M and 0.35 M, respectively – results in a 21.8 times Na (as Na2SO4) and 58.3 times SO4 change in stoichiometric ratio to REE. Results strongly indicate a straightforward approach for REE recovery from NiMH battery waste without the need to increase the pH of PLS.
Over the past two decades, Unmanned Aerial Vehicles (UAVs), more commonly known as drones, have gained a lot of attention, and are rapidly becoming ubiquitous because of their diverse applications such as surveillance, disaster management, pollution monitoring, film-making, and military reconnaissance. However, incidents such as fatal system failures, malicious attacks, and disastrous misuses have raised concerns in the recent past. Security and viability concerns in drone-based applications are growing at an alarming rate. Besides, UAV networks (UAVNets) are distinctive from other ad-hoc networks. Therefore, it is necessary to address these issues to ensure proper functioning of these UAVs while keeping their uniqueness in mind. Furthermore, adequate security and functionality require the consideration of many parameters that may include an accurate cognizance of the working mechanism of vehicles, geographical and weather conditions, and UAVNet communication. This is achievable by creating a simulator that includes these aspects. A performance evaluation through relevant drone simulator becomes indispensable procedure to test features, configurations, and designs to demonstrate superiority to comparative schemes and suitability. Thus, it becomes of paramount importance to establish the credibility of simulation results by investigating the merits and limitations of each simulator prior to selection. Based on this motivation, we present a comprehensive survey of current drone simulators. In addition, open research issues and research challenges are discussed and presented.
The influence of an applied mechanical pressure on the electrochemical performance and the aging of 1.4 Ah graphite/NMC622 stacked Lithium-ion battery cells (LiBs) is investigated comprehensively on the electrode and the full cell level. Pressure dependent ionic pore resistance measurements reveal an increase of the ionic pore resistance in both, the anode and the cathode of 6% and 2.9%, respectively at a pressure of 0.84 MPa. Compressibility measurements expose an interesting nonlinearity of the compressibility and the number of layers in an electrode stack, which must be considered for the cell application. The applied pressure improves the electrical contact in the cell. However, by the increase of both, the ionic pore resistance and the charge transfer resistance, the reversible capacity loss is strongly dependent on the applied C-rate during the cycling. For C-rates above 0.8C the polarization losses of the compressed cells are around 7.3% in comparison to 2.1% for the uncompressed cells. Contrariwise, for C-rates below 0.8C the compression of the cells is beneficial and leads to a capacity increase of 2.0% compared to the uncompressed cells. The subsequent post-mortem analysis demonstrates the negative influence of the absence of a homogeneous pressure distribution within the uncompressed cells.
Ni-rich LiNi0.8Co0.15Al0.05O2 (NCA) is considered as one of the most attractive cathode materials for Li-ion batteries. However, poor thermal stability and cycle performance for this material have to be faced. In this work, to promote the cycle and thermal stability of NCA cathode without lessening its discharge capacity, for the first time, quasi-concentration-gradient NCA cathode (QCG-NCA) is designed and synthesized with multi-shell precursor. The electrochemical properties and thermal stability of QCG-NCA are compared to homogeneous LiNi0.8Co0.15Al0.05O2 (HG-NCA), core material LiNi0.85Co0.15O2 (HG-NC) and the outer shell material LiNi0.6Co0.15Al0.25O2 (HG-NCA25). As expected, QCG-NCA exhibits higher discharge capacity (198.1 mA h g−1 at 20 mA g−1), higher capacity retention (87.8% at 0.2C after 200 cycles; 70.9% at 1C after 500 cycles) and better thermal stability than the homogeneous one. Reasons of these enhancements are investigated in this work. This strategy extends the concept of concentration-gradient structure and offers a new strategy suitable for practical application to modify the NCA cathode material.
Direct oxidation alkaline fuel cells (DOAFCs) possess particular advantages on the possibility of employing low cost non-noble metal catalysts. A wide range of fuels can be used due to superior reaction kinetics in alkaline media. The development of DOAFCs was hindered by the carbonation of electrolyte due to the presence of CO2. The application of the anion exchange membrane (AEM) provides the possibility of reducing the effect of carbonation and fuel crossover which is an issue in the proton exchange membrane fuel cells (PEMFCs). The latest developments in alkaline fuel cells are examined in this paper, considering different types of fuels, novel catalysts and anion exchange membranes. Moreover, alkaline fuel cell systems and configurations are studied, particularly the new designs for portable or microelectronic devices. Further development of DOAFCs will rely on novel AEMs with good ionic conductivity and stability, low cost non-Pt catalysts with high activity and good stability for various fuels and oxidant. We envisage that DOAFCs will play a major role in energy research and applications in the near future.
A hydrometallurgical method involving natural organic acid leaching has been developed for recovery of lithium and cobalt from the cathode active materials in spent lithium-ion batteries. Succinic acid is employed as leaching agent and H2O2 as reductant. The cobalt and lithium contents from the succinic acid-based treatment of spent batteries are determined by inductively coupled plasma-optical emission spectroscopy to calculate the leaching efficiency. The spent LiCoO2 samples after calcination and the residues after leaching are characterized by X-ray diffraction and scanning electron microscopy. The results show that nearly 100% of cobalt and more than 96% of lithium are leached under optimal conditions: succinic acid concentration of 1.5 mol L−1, H2O2 content of 4 vol.%, solid-to-liquid ratio of 15 g L−1, temperature of 70 °C, and reaction time of 40 min. Results are also given for fitting of the experimental data to acid leaching kinetic models.
To compare psychological characteristics of patients seeking laparoscopic adjustable gastric band (LAGB) and gastric bypass surgery.
The unique interconnected mesoporous structure and high specific surface area facilitate the diffusion and absorption of Na+, making ordered mesoporous carbon a promising candidate for the anode of sodium-ion batteries. However, low electronic conductivity and scanty defects cause unsatisfied sodium storage capacity. Heteroatoms doping is regarded as an efficient strategy to modify the physicochemical properties of carbonaceous materials and in this work, nitrogen and sulfur are simultaneously doped into the framework of ordered mesoporous carbon via a one-step thermal treatment. The N/S co-doped samples possess an enhanced electronic conductivity, rich defects, and improved Na+ adsorption capability, realizing a superior capacity of 419 mA h g−1 at 0.1 A g−1 after 150 cycles and retaining 220 mA h g−1 at 5 A g−1 even after 3000 cycles. As a consequence, the facile synthetic route and excellent sodium storage properties make N/S co-doped ordered mesoporous carbon show great prospect for the application of sodium-ion batteries anode material.
Krabbe disease is a rare inherited neurologic disorder affecting the central and peripheral nervous systems. The disease has four phenotypes: early infantile, later onset, adolescent, and adult. The only known treatment is hematopoietic stem cell transplantation, which is, in the early infantile form of the disease, most beneficial if performed before onset of clinical symptoms. In August 2006, New York State began screening all newborns for Krabbe disease. A rapid and accurate technique for assessing galactocerebrosidase activity and performing DNA mutation analysis had been developed. Interpreting these results was limited, however, because neither enzyme activity nor genetic mutation reliably predicts phenotype. A series of initiatives were therefore developed by a multidisciplinary group of neurologists, geneticists, metabolic pediatricians, neurodevelopmental pediatricians, and transplant physicians (the Krabbe Consortium of New York State) to enhance the effectiveness of the newborn screening program. A standardized clinical evaluation protocol was designed based on the available literature, criteria for transplantation for the early infantile phenotype were formulated, a clinical database and registry was developed, and a study of developmental and functional outcomes was instituted. This multidisciplinary standardized approach to evaluating infants who have positive results on newborn screening may serve as a model for other states as they begin the process of screening for Krabbe disease and other lysosomal storage disorders.
There are few comprehensive reviews of breast cancer outcomes in older women. We synthesize data to describe key findings and gaps in knowledge about the outcomes of breast cancer in this population.
The electrolyte of a used lithium-ion battery from a hybrid electric vehicle (HEV) was investigated. The liquid electrolyte was collected through the pressure valve of these 5 Ah cells. It consists of (29.8 ± 0.2) wt.% dimethyl carbonate (DMC), (21.7 ± 0.1) wt.% ethyl methyl carbonate (EMC), (30.3 ± 0.3) wt.% ethylene carbonate (EC) and (2.2 ± 0.1) wt.% cyclohexyl benzene (CHB) which were identified with GC–MS and quantified with GC–FID. Li+ (1.29 ± 0.04) mol L−1 and PF6 − were determined with IC as the main ionic species in the solution. Furthermore, BF4 − was clearly identified with IC–ESI–MS, IC–ICP–MS and 11B NMR and quantified to a concentration of (120.8 ± 8.3) mg L−1 with ICP–OES. The presence of POF3 (detected with GC–MS), F−, PO2F2 −, HPO3F− and H2PO4 − (determined with IC–ESI–MS) can be attributed to the reaction of the conducting salt LiPF6 via PF5 with traces of water. HPO3F− and H2PO4 − could only be observed in cells which were opened in a laboratory hood under exposure of air humidity. This experiment was done to simulate escaping electrolyte from an HEV battery pack. Furthermore, several alkyl phosphates (identified with GC–MS and IC–ESI–MS) are present in the solution due to further reaction of the different fluorinated phosphates with organic carbonates.
In spite of the recent advancements, rational design and synthesis of non-precious metal oxygen redox catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in both alkaline and acidic media is still a crucial challenge for the development of rechargeable metal-air batteries and regenerative fuel cells. Heteroatom doped carbon-based materials exhibit a promising strategy to achieve the bifunctionality within one catalyst. Herein, we report a highly efficient Fe-N-C oxygen redox catalyst derived from a new class of Fe coordinated bis(imino)-pyridine ligand based polymer synthesized via Schiff base condensation between 2,6-diacetylpyridine and 1,8-diaminonaphthalene. The Fe-N-C catalyst prepared by this precursor without templates or supports is characterized by spherical structure, ultrahigh specific surface area up to 1796.0 m2/g, a high degree of graphitization and atomically dispersed five-coordinated Fe-N5 sites. These unique features endow the catalyst with outperforming performance for ORR and OER in terms of remarkable activity and stability in both alkaline and acidic media. The overall oxygen redox activity (ΔE = Ej=10 − E1/2) (0.70 V in alkaline media and 0.86 V in acidic media) of the catalyst for both ORR and OER is much higher than those of none precious metal catalysts previously reported. These outstanding features remark the great possibility of the introduced catalyst for the practical application.
Wearable electronics have attracted attention for their potential use in constructing a human-centered intelligent world. As one of the most promising materials for constructing high-performance self-powered wearable electronics, piezoelectrets possess the advantages of high flexibility, light weight, biocompatibility and high piezoelectric performance. Herein, recent advances in this area are reviewed. First, the mechanism, theoretical progress, and manufacturing techniques of piezoelectrets are presented. Then, devices based on different piezoelectret materials as human-body mechanical energy harvesters are introduced in sequence, and their major applications are demonstrated, including self-powered acoustic transducers, flexible pressure sensors and wearable physiological monitors. At the end of this review, the perspectives and challenges of piezoelectrets are discussed. We anticipate that traditional piezoelectrets with unique designs will play important roles in wearable energy harvesting and human physiological signal monitoring in the near future.
“Automatic” speech, especially counting, is frequently preserved in aphasia, even when word production is severely impaired. Although brain sites and processes for automatic speech are not well understood, counting is frequently used to elicit fluent speech during preoperative and intraoperative cortical mapping for language. Obtaining both behavioral and functional brain imaging measures, this study compared counting with a word production task (generation of animal names), including non-verbal vocalizations and quiet rest as control states, in normal and aphasic subjects. Behavioral data indicated that normal and aphasic groups did not differ in counting or non-verbal vocalizations, but did differ significantly in word production (“naming” animals). Functional brain imaging results on normal subjects using partial least squares analysis of PET rCBF images revealed three significant latent variables (LVs): one for naming and vocalizing, identifying bilateral anterior areas, with left predominating over right; a second LV for naming, identifying left and right frontal and temporal areas. For the third, only marginally significant LV, which was associated with automatic speech alone (counting), right and subcortical sites predominated. For patients, two LVs emerged, identified with naming and vocalization, and corresponding to a variety of cerebral sites; the analysis failed to find a specific latent variable for counting. A comparison between group data for normal subjects and patients suggested that the naming, counting, and vocalization tasks were performed differently by the two groups. These results suggest that word generation as a verbal task is more likely to elicit activity in classical language areas than counting. Further studies are suggested to better understand differences between neurological substrates for non-propositional and automatic speech.
Planetary explorations of human beings necessitate the research of the influence of γ-radiation on lithium-ion cells. In this study, the radioactive Co-60 was used as the radiation source. The electrochemical performances of LiCoO2/graphite full cells and LiCoO2/Li half-cells with a LiPF6-based electrolyte were measured before and after the radiation. The structural and compositional changes of the cell components were evaluated by means of X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), and 1H nuclear magnetic resonance spectroscopy (1H NMR). The experimental results indicate that the cell performance is substantially deteriorated after the radiation due to two aspects of changes, i.e. radiation-induced defects in LiCoO2 and production of carboxyl in the electrolyte. The cell degradation is more pronounced for the LiCoO2/C full cells than for LiCoO2/Li half-cells owing to the reaction between active lithium and the carboxyl.
Despite recent improvements in genotoxicity protocols, we have observed an increase in the occurrence of positive results, particularly in chromosomal aberration tests in vitro, yet very few of these are accompanied by positive responses in vivo. Thus, the positive results may not be biologically relevant either for rodents or humans in vivo, but how should we determine “biological relevance”? Chemicals that produce thresholded dose–responses may well not pose a genotoxic risk at low (relevant to human) exposures, but thresholds should not just be “seen”; there must be an explanation and understanding of the underlying mechanism. In addition to extremes of pH, ionic strength and osmolality, as have been identified previously, such mechanisms include indirect genotoxicity resulting from interaction with non-DNA targets, chemicals/metabolites which are inherently genotoxic but which, at low concentrations, are effectively conjugated and unable to form adducts, and production of specific metabolites under in vitro conditions that are not formed in rodents or humans in vivo. If such thresholded mechanisms can be identified at exposures which are well in excess of expected human exposure, then there may be a strong argument that the positive results are not biologically relevant.
The interest in self-consumption of PV electricity from grid-connected residential systems is increasing among PV system owners and in the scientific community. Self-consumption can be defined as the share of the total PV production directly consumed by the PV system owner. With decreased subsidies for PV electricity in several countries, increased self-consumption could raise the profit of PV systems and lower the stress on the electricity distribution grid. This review paper summarizes existing research on PV self-consumption and options to improve it. Two options for increased self-consumption are included, namely energy storage and load management, also called demand side management (DSM). Most of the papers examine PV-battery systems, sometimes combined with DSM. The results show that it is possible to increase the relative self-consumption by 13–24% points with a battery storage capacity of 0.5–1kWh per installed kW PV power and between 2% and 15% points with DSM, both compared to the original rate of self-consumption. The total number of papers is however rather limited and further research and more comparative studies are needed to give a comprehensive view of the technologies and their potential. Behavioral responses to PV self-consumption and the impact on the distribution grid also need to be further studied.