batterydata/paper-abstracts huggingface dataset:
A bifunctional air cathode for the electrochemical oxygen reduction and evolution in a Li-O2 battery comprising Co-CoO nanoparticles embedded in the nitrogen-doped carbon nanorods (Co-CoO/N-CNR) is presented. The nanorod morphology with mesoporous nanostructures can handle continuous formation and decomposition of Li2O2 and favors the transport of electrons and ions, therefore improves the rate capability and cycle stability. Moreover, the hierarchical mesoporous Co-CoO/N-CNR reduces the overall overpotential over the cycle and decreases the side reaction between Li2O2 and carbon surface, leading to a significant enhancement of the specific capacity and cycling capability. With the cooperative effect of Co-CoO/N-CNR and porous nature, Co-CoO/N-CNR cathode delivers a high discharge specific capacity of 10,555 mAh g−1 at 100 mA g−1 and long cycle stability for over 86 cycles without any capacity loss at a high cutoff capacity of 1000 mAh g−1. Furthermore, excellent performance of 7514 mAh g−1 at 500 mA g−1 is achieved.
MnO2 · nH2O-EG composites for electrochemical capacitors were prepared using commercially available low cost exfoliated graphite (EG) as a conductive substrate, and (a) potassium permanganate and (b) manganese(II) acetate solutions by two different routes. Method (1) was addition of EG to (a), followed by 1 h stirring and then slow addition of (b), and in Method (2) the solutions (a) and (b) were swapped. Using Method (1) submicron or smaller sized MnO2 · nH2O particles having mesopores were formed, whereas Method (2) produced lumps of aggregated particles of several tens microns without mesopores, though specific surface areas were not very different and both were similar by XRD. Although EG alone showed only about 2 F g−1, the capacitance per net amount of MnO2 in 1 mol L−1   Na2SO4 solution increased proportionally with EG content and was always larger by Method (1) than Method (2), that is, the utilization ratio of MnO2 increased with EG content and the effect was more prominent in the case of Method (1). The results indicated that EG is a good conductive material for MnO2 · nH2O electrochemical capacitors if appropriate synthesis processes are used. The performance of the composites strongly depends on synthesis method, even using the same raw materials. It was suggested that the morphology of the products was a primary factor leading to different performance rather than composition.
Sodium sulfur (NaS) cell is recognized as a promising candidate for advanced grid-scale large energy storage systems (ESS). In this work, we study the impacts of planar NaS cell container materials on the accumulation of residual stresses in the cell joints and solid electrolyte during the cell assembly and operation processes. Concentration of such thermo-mechanical stress in these vulnerable areas in the modern NaS cells can lead to catastrophic cell failures, which can present a huge challenge for developing large planar NaS cells towards commercial deployment. Here, we employ the finite-element analysis (FEA) computational technique to quantitatively assess the thermo-mechanical stress accumulation using prototype planar NaS cells. Relevant experimental procedures with corresponding thermal cycling conditions for the cell assembly, operation, and maintenance processes are incorporated into the FEA model. The influences of Al alloy (Al3003), stainless steels (STS304 and STS340), and iron-nickel-cobalt superalloy (KOVAR) on the residual stress accumulation are tested and thoroughly discussed. The computation results show that high stress concentration can be developed in the cell joint area. Through the comprehensive computational analysis, it is suggested that applying smaller CTE (less than ∼12×10−6 K−1) alloys is necessary to secure the thermo-mechanical stability of NaS cells that can be implemented in a large scale ESS.
Studies suggest that the left insula may play an important role in speech motor programming. We used functional magnetic resonance imaging to investigate the role of the left insula in the production of monosyllabic or multisyllabic words during overt and covert speech conditions. The left insula did not show a BOLD response for multisyllabic words (which should require more speech motor programming) that was different from that for monosyllabic words. Left parietal lobe regions showed a greater response for multisyllabic as compared to monosyllabic words. This is consistent with clinical studies showing that left parietal lobe lesions can produce a deficit in speech programming. Despite similarities, covert and overt speech did not demonstrate the same patterns of BOLD response. The BOLD response was greater during overt speech in areas that have been shown to play an important role in speech production including left premotor cortex/BA6, left primary motor cortex, left insula, and left superior temporal gyrus.
The combination of energy generation and energy storage systems is the ultimate solution to meet the ever-increasing demand for high-energy-density power sources. Here, we demonstrate a new class of monolithically integrated, photo-rechargeable portable power sources based on miniaturized crystalline Si photovoltaics (c-Si PVs) and printed solid-state lithium-ion batteries (LIBs). A solid-state LIB with a bipolar cell configuration is fabricated directly on the aluminium electrode of a c-Si PV module through an in-series printing process, which enables the seamless architectural/electrical connection of the two different energy systems. The single-unit PV–LIB device shows exceptional electrochemical performance that lies far beyond those achievable by conventional PVs or LIBs alone: it displays fast, low-light-intensity and high-temperature photo-charging; a photo-electric conversion/storage efficiency of 7.61%; a sustainable cycling performance; and continuous discharging at an extremely high current density of 28C under sunlight illumination. This study opens a facile and scalable route for the development of single-unit, photo-rechargeable mobile high-performance batteries that are required for the future era of ubiquitous electronics.
The absorptive separator plays an important role in the operation of valve-regulated lead–acid (VRLA) batteries. The composition and physical characteristics of recombinant-battery separator mats (RBSMs), also known as absorptive-glass mats (AGMs), directly affect three critical factors associated with the performance of VRLA batteries. The factors are: electrolyte supply, oxygen-transport, and constraint of positive active-material growth. This paper discusses the influence of the physical properties of RBSMs on the performance of VRLAs, explains how these properties are measured, and defines the characteristics of an ideal separator. Separators used presently in VRLAs meet some of these criteria, but development of advanced materials is required to improve battery life.
We investigated whether cornin, an iridoid glycoside isolated from fruits of Verbena officinalis L., regulated angiogenesis and thereby improved functional outcomes after stroke and discovered a potential mechanism. The effects of cornin on proliferation of rat artery smooth muscle cell (RASMC) and signalling was investigated in vitro. Adult male rats were subjected to 1 h of middle cerebral artery occlusion (MCAO) and reperfusion and treated with or without 25 mg/kg of cornin, starting 24 h after ischemia and reperfusion, by continuous intravenous injection daily for 14 days. Neurological functional tests were performed and cerebral Evans blue extravasation was measured. Angiogenesis and angiogenic factor expressions were measured by immunohistochemistry and Western blotting, respectively. Cornin increased the proliferation of RASMC and enhanced the expression of Wnt5a, β-catenin, cyclin D1 and angiopoietin-1 (Ang1). Cornin treatment promoted angiogenesis in the ischemic brain core and improved functional outcomes after stroke. Cornin-treated MCAO rats showed significant increase in vascularization and expression of vascular endothelial growth factor and Ang1 and phosphorylation of Tie2 and Akt compared with vehicle-treated MCAO rats. The Ang1/Tie2 axis and Wnt/β-catenin pathways appear to mediate cornin-induced angiogenesis.
The rhombohedral LiSn2(PO4)3 was prepared by solid-state method for the anode material of lithium-ion battery. The effect of pH value of hydrothermal reaction system on the morphology of SnO2 as the precursor of LiSn2(PO4)3 and the influence of heat-treatment procedure and conditions, such as the sintering temperature and time, on the property of LiSn2(PO4)3 were investigated. The purity, morphology, structure and size distribution of prepared LiSn2(PO4)3 were characterized respectively by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM) methods. The results demonstrate that the as-prepared LiSn2(PO4)3 particles exhibit rhombohedral single-crystal structure with an average particle size of 200 nm. The electrochemical measurement results reveal that the as-prepared LiSn2(PO4)3/C electrode exhibits the improved cycling stability and reversibility with a reversible discharge capacity of 448.6 mA h g−1 at 100 mA g−1 and better rate capability of 332.6 mA h g−1 at 500 mA g−1. The charge-discharge mechanism of LiSn2(PO4)3/C electrode was also investigated. According to the test results of cyclic voltammetry, the electrode process includes not only the intercalation and deintercalation of lithium ions in the LiSn2(PO4)3 particles, but also the surface pseudo-capacitive effect.
A family of proton conducting membranes based on cross-linked poly(vinyl alcohol), PVA, has been synthesized and characterized. The influence of surface-functionalized silica particles on the membrane properties has been evaluated by means of 1H-NMR, vibrational spectroscopy, thermal analysis and electrochemical characterization. The study revealed that the crystallinity of the polymer, the proton diffusivity and the water retention are strongly affected by the presence of the inorganic compound. Conductivity measurements and preliminary fuel cell tests agreed in determining the best PVA/silica ratio among the various compositions explored and demonstrated the potentiality of the selected membranes as electrolytes in fuel cell devices.
The sixth High Temperature Processing Symposium will bring leading researchers, scientists, engineers and industry associates together to exchange and share their research results, new ideas, and experiences on all aspects of high-temperature processing. The conference is held every year and is an ideal platform for delegates from academia and industry to discuss the practical challenges encountered with high-temperature processing and the solutions adopted.
Publisher Summary This chapter reviews coal as a raw material, which is mainly used for the generation of power and in the iron and steel industry. Coal and its byproducts are also used in alumina refineries, the chemical and pharmaceutical industry, and in other areas such as the manufacture of paper. It is defined that to obtain chemicals from coal, several strategies are reported that include: gasification followed by a sequence of carbon chemistry processes, the conversion of coal via carbonization, pyrolysis, or liquefaction to liquids and tars followed by the conversion of the components of these derived products to higher value products, the direct conversion of coals to chemicals or materials, and the coproduction of chemicals or materials and fuels along with electricity. The chapter is mainly devoted to solid carbon materials derived from coal and coal byproducts, in which the conventional methods of coal petrology play an important role. Other coal-derived materials such as those obtained from the combustion, gasification, liquefaction, and carbonization processes are also described.
Impairment of inhibition-related functions is one of the most pronounced cognitive deficits found in attention-deficit/hyperactivity disorder (ADHD). Compelling evidence from studies of unaffected relatives of patients with ADHD and of ADHD-like traits in healthy subjects suggest the continuous distribution of ADHD symptoms in the population. A more subtle inhibitory deficit can also be found in healthy relatives of patients and in subjects with high ADHD-like traits. Here, we examined the relationship between inhibitory performance and ADHD-like traits, for the first time, in a large sample of healthy adults by applying multiple, widely used tests of inhibition-related functions. ADHD-like traits, in general, were independently predicted by Stroop interference score and, at trend level, by go/no-go commission error rate while controlling for socio-demographic factors, verbal intelligence and neuroticism. Additionally, higher inattentive traits were related to worse Stroop performance at trend level, and higher hyperactive/impulsive traits were significantly associated with more go/no-go commission errors. ADHD-like traits were strongly related to neuroticism. The study shows that individual differences in ADHD-like traits are related to variance in fundamental inhibition-related functions over and above effects of negative affect regulation, but the relationships tend to be small. The results suggest the quasi-dimensionality of ADHD and raise further questions about the relationship between genetic factors and the deficit of inhibition-related functions in the ADHD spectrum.
This study employs experimental techniques to measure the changing internal resistance of flooded, flat-plate lead-acid batteries during container formation, revealing a novel indicator of formation completeness. In order to measure internal resistance during formation, d.c. current pulses are superimposed over the constant formation current at set intervals, while change in voltage is measured. The resulting “pulsed” internal resistance is divided into ohmic and interfacial components by measuring the ohmic resistance with short d.c. pulses as well as with a.c. injection. Various constant-current container formations are carried out using different current levels, plate thicknesses, and pulsing techniques, yielding an array of resistance trends which are explained using Butler-Volmer kinetic theory. Ohmic and interfacial resistance trends are shown both theoretically and experimentally to eventually decay to a predictable steady-state value as the formation proceeds, suggesting that this internal resistance method can be used to detect the completion of the formation. The same principles are shown to apply to recharge cycles as well, but with potentially limited practical implications in comparison to formation.
We show that it is possible to achieve higher energy density lithium–oxygen batteries by simultaneously lowering the discharge overpotential and increasing the discharge capacity via thermodynamic variables alone. By assessing the relative effects of temperature and pressure on the cell discharge profiles, we characterize and diagnose the critical roles played by multiple dynamic processes that have hindered implementation of the lithium–oxygen battery.
We report on time-dependent density functional theory calculations to study the chiroptical properties of small Nb9
A modified electrode for vanadium redox flow battery (VRFB) has been developed in this paper. The electrode is based on a traditional carbon felt (CF) grafted with the short-carboxylic multi-walled carbon nanotubes (MWCNTs). The microstructure and electrochemical property of the modified electrode as well as the performance of the VRFB single cell with it have been characterized. The results show that the MWCNTs are evenly dispersed and adhere to the surface of carbon fibres in the CF. The electrochemical activities of the modified CF electrode have been improved dramatically and the reversibility of the VO2 +/VO2+ and V3+/V2+ redox couples increased greatly. The VRFB single cell with the modified CF exhibits higher coulombic efficiency (93.9%) and energy efficiency (82.0%) than that with the pristine CF. The SEM analysis shows that the MWCNTs still cohere with carbon fibres after charge and discharge test, indicating the stability of the MWCNTs in flowing electrolyte. Therefore, the composite electrode presents considerable potential for the commercial application of CF in VRFB.
Phenolic compounds are widely distributed in the natural environment, typically existing as a mixture at the nanogram or microgram per liter level. Among the phenolic compounds, 4-nonylphenol, 4-t-octylphenol, bisphenol A and 2,4-dichlorophenol attract the most concern due to their abundance and risks within the natural environment. The former three chemicals are known as endocrine disruptors causing feminization in various organisms, whereas the latter one requires further clarification concerning its feminization effect. This study aims to evaluate the combined effects of these chemicals using vitellogenin protein induction in male juvenile goldfish Carassius auratus as an endpoint after 15 days of exposure. The results showed that all these chemicals can induce vitellogenin with a relative potency of 4-t-octylphenol > bisphenol A > 4-nonylphenol ≫ 2,4-dichlorophenol. 2,4-dichlorophenol showed a very weak estrogenic effect with an induction of vitellogenin concentration of <1 % of positive control, and it is therefore omitted in further tests to evaluate their combined effect. The other three chemicals were mixed in two ways, at an equipotent ratio and at an equal environmental level ratio, and their combined effects were evaluated with both the toxicity units method and concentration addition model. The resulting effect of exposure to both mixtures showed that these chemicals generally exhibited an additive effect. The ecological risk of phenolic chemicals may therefore be underestimated if based on the presence of single chemicals whereas their combined effects warrant further consideration.
The thermal stability and chemical structure of solid electrolyte interphase (SEI) formed on a natural-graphite negative-electrode in ethylene carbonate (EC) and dimethyl carbonate (DMC)-based electrolyte was investigated by thermogravimetry-differential thermal analysis combined with mass spectrometry (TG-DTA/MS) and X-ray photoemission spectroscopy (XPS). Due to the decomposition of SEI, two CO2 evolution peaks at around 330 and 430°C were detected in TG-MS studies with continuous CO2 background. The continuous CO2 background was attributed to the gradual decomposition of oxygen-containing polymeric species of SEI. Another two dominant components of SEI, lithium alkyl carbonate and lithium oxalate, were found to contribute to the CO2 peaks at 330 and 430°C separately. The effects of charging-depth, current density and cycle number on the CO2 distribution and XPS spectra were studied. It was found that lithium oxalate was reduction product of lithium alkyl carbonate during the intercalation of lithium ions. The reduction reaction could be accelerated by elevated temperature. The transformation of SEI chemical structure showed direct effect on the thermal stability of SEI. At the same time, lithium carbonate was also found in SEI on the graphite electrode after long cycles, while it was negligible in the electrode subjected to short cycles.
The removal of cadmium from aqueous solution was carried out by electrocoagulation using magnesium as anode and stainless steel as cathode. Various operating parameters on the removal efficiency of cadmium were investigated, such as initial cadmium ion concentration, initial pH, current density and temperature. The optimum removal efficiency of 98.6% was achieved at a current density of 0.2 A dm−2 at a pH of 7.0. The experimental data were tested against different adsorption isotherm models for describing the electrocoagulation process. The adsorption of cadmium preferably fitting the Langmuir adsorption isotherm suggests monolayer coverage of adsorbed molecules. First and second-order rate equations were applied to study adsorption kinetics. The adsorption process follows second order kinetics model with good correlation. Temperature studies showed that adsorption was endothermic and spontaneous in nature.
Although in vivo models give a more accurate reflection of the activity of substances used in traditional medicine, their use in many countries is severely restricted due to economic and ethical concerns, and this has resulted in the widespread use of in vitro tests in ethnopharmacological studies. Such tests are very useful where the identity of compounds responsible for the biological activity of an extract is being investigated and where limited supplies of material are available, but it is important to consider a variety of factors before making over-predictive claims of that activity in one particular system explains the traditional use. The use of only one bioassay gives a very incomplete picture of the effect of the extract on the whole system involved. A symptom may be due to a number of disease states and, consequently, a variety of mechanisms may serve as targets for bioassays. In a similar way, it is very unusual for there to be only one target for a particular disease so a variety of test systems must be employed. Examples are given of batteries of test systems used to test plants and other materials with a reputation of being useful in wound-healing, diabetes, cancer and to treat cognitive decline associated with old age. In addition, consideration must be given to factors such as absorption into the body and metabolism of any substances present, either to decrease or increase the effect of the ‘actives’.
This work is focused on the effect of selected organic additives on zinc deposit properties in relation to a possible utilizing the additives for a zinc based battery systems worked with alkaline electrolyte. The Zn layers were deposited on tin substrate from the KOH based electrolytes saturated by zinc oxide and with addition of different organic surfactants - CTAB, Slovasol 2520/2, Tween 20 and Lugalvan G 35 in concentration 500 ppm. Depositions were held under low current densities 10 mA/cm2 where the mossy porous deposit grows from pure KOH solutions. All additives were examined with emphasis on the study of zinc deposit morphology and their ability to create uniformly distributed porous structure which could exhibit fast electrode kinetic. All deposits were studied by X-ray crystallography and preferred structure orientations are reported. For the purpose of using additives directly in the battery systems we evaluated also the corrosion properties of the KOH solution with addition of the above mentioned surfactants. It has been found that the presence of CTAB and Slovasol 2520/2 lead to a pyramidal texture, Lugalvan G 35 produced micro-crystalline deposit with opened porous structure and finally presence of Tween 20 lead to nano-crystalline highly porous deposit almost without preferred orientation.