batterydata/paper-abstracts huggingface dataset:
A promising approach to improving the energy density of the all-vanadium redox flow battery while also saving on raw materials costs, is to eliminate the positive half-cell electrolyte and replace it with an air electrode to produce a hybrid vanadium–oxygen redox fuel cell (VOFC). This concept was initially proposed by Kaneko et al. in 1992 and first evaluated at the University of New South Wales by Menictas and Skyllas-Kazacos in 1997. In this project the performance of the VOFC over a range of temperatures and using different types of membranes and air electrode assemblies was evaluated. Despite early problems with the membrane electrode assemblies that saw separation of the membrane due to swelling and expansion during hydration, with improved fabrication techniques, this problem was minimized and it was possible to operate a 5-cell VOFC system for a total of over 100 h without any deterioration in its performance.
This paper presents new forms of urban renewable energy, in particular, the integration of solar and wind power into the industrial and commercial buildings with flat roofs which populate a city's downtown core. This combination of renewable energy passively adapts to pre-existing structures and exploits them to their full advantage. The working prototypes presented aim to introduce an element of multi-functionality to building-integrated photovoltaics (BIPV), creating systems which produce energy while meeting required needs and desirable features of urban buildings. We also explore the combination of wind energy and various energy efficiency initiatives with BIPV designs. Our energy efficiency initiatives include a new method of generating the perception of natural sunlight from artificial light and brainwave controlled lighting that dims automatically when occupants’ concentration is lowered. These efforts result in an environment that celebrates the existential notion of self-empowerment through reducing energy consumption and having control over one's own energy production. Our discussion follows into market considerations of our BIPV designs and how project costs are lowered and space is conserved, assets when designing for urban locations. The test site for the development of urban renewable energy is the Existential Technology Research Center (ETRC), located in downtown Toronto, Canada.
Composite materials composed of titanium–silicon alloy (Ti–Si alloy) core and porous Si shell (core–shell (C/S) composite) are prepared, and their electrochemical performance as anode materials for lithium-ion batteries is reported. The C/S composites are fabricated by selective etching of the titanium silicide phase in the surface region of a Ti–Si alloy that consists of titanium silicide and Si phases. The Ti–Si alloy is mechanically alloyed (MA) by ball-milling a mixture containing elemental Si and TiH2. Prior to the etching treatment, some of the MA samples are annealed at temperatures ranging from 600 to 800 °C to further develop the crystalline structure; annealing leads to the increase in the crystallite size of the Si and silicide phases. Thereby, the core and shell structure of the C/S composites and their electrochemical behaviors are controlled. Electrodes prepared by blending the C/S composites with graphite show good cycle performance and rate capability.
The handling of left ventricular assist devices (LVADs) can be challenging for patients and requires appropriate training. The devices’ usability impacts patients’ safety and quality of life. In this study, an eye tracking supported human factors testing was performed to reveal problems during use and test the trainings’ effectiveness. In total 32 HeartWare HVAD patients (including 6 pre-VAD patients) and 3 technical experts as control group performed a battery change (BC) and a controller change (CC) as an everyday and emergency scenario on a training device. By tracking the patients’ gaze point, task duration and pump-off time were evaluated. Patients with LVAD support ≥1 year showed significantly shorter BC task duration than patients with LVAD support <1 year (p = 0.008). In contrast their CC task duration (p = 0.002) and pump-off times (median = 12.35 s) were higher than for LVAD support patients <1 year (median = 5.3 s) with p = 0.001. The shorter BC task duration for patients with LVAD support ≥1 year indicate that with time patients establish routines and gain confidence using their device. The opposite effect was found for CC task duration and pump-off times. This implies the need for intermittent re-training of less frequent tasks to increase patients’ safety.
In terms of global forest product market developments, the twenty-first century has been in many ways very different from the twentieth century—striking structural changes have taken place. The global forest sector can be interpreted to be in a phase of creative destruction—an era characterized by a major decline of a number of established products and businesses, and simultaneous emergence of new products and businesses.
An anode system based on intermetallic phases with a zinc-blende-type structure (InSb, GaSb and AlSb) has been studied for lithium-ion batteries. The compound, InSb, in particular, cycles well between 1.2 and 0.5V. After an initial “conditioning” cycle, a mechanism involving lithium insertion into an open framework structure followed by indium extrusion in the potential range 1.2–0.7V, appears to dominate; between 0.7 and 0.5V, a more complex mechanism occurs involving indium extrusion from a stable fcc Sb anion array and subsequent lithiation of the extruded indium. In situ X-ray diffraction and extended X-ray analysis fine structure (EXAFS) data were obtained over the voltage window 1.2–0.5V, where a rechargeable capacity of 300mAh/g is achievable. The results indicate that after the “conditioning” reaction a Li y In1−y Sb zinc-blende framework, in which Li atoms partially substitute for In, is responsible for the good cycling behavior of the cells. Isostructural AlSb and GaSb electrodes provide inferior electrochemical capacities.
The structural design and synthesis of sulfur-carbon composite materials with high performance is still a major challenge for rechargeable lithium-sulfur batteries. Interconnected three-dimensional frameworks comprising multi-walled carbon nanotubes, graphene, or carbon particles offer a combination of constituent advantages and can thus be used to achieve superior energy conversion and storage properties. Herein, we designed and prepared free-standing three-dimensional sulfur papers containing interconnected highly conductive carbon materials, which enable to be flexible binder-free cathodes for Li-S batteries. The resultant sulfur-carbon composite paper cathode exhibited high reversible specific capacity of 1386 mAhg−1, good rate capability up to 5C, and excellent cycling performance (a capacity retention 68% after 400 cycles), all of which are significantly improved from those of bare sulfur cathode or sulfur-GO composite only. Rational design of cathode composition, structure, and a simple fabrication process can give insight into the development of various advanced cathode materials for high-performance Li-S batteries.
Solid-state polymer–silicate nanocomposite electrolytes based on an amorphous polymer poly[(oxyethylene)8 methacrylate], POEM, and lithium montmorillonite clay were fabricated and characterized to investigate the feasibility of their use as ‘salt-free’ electrolytes in lithium polymer batteries. X-ray scattering and transmission electron microscopy studies indicate the formation of an intercalated morphology in the nanocomposites due to favorable interactions between the polymer matrix and the clay. The morphology of the nanocomposite is intricately linked to the amount of silicate in the system. At low clay contents, dynamic rheological testing verifies that silicate incorporation enhances the mechanical properties of POEM, while impedance spectroscopy shows an improvement in electrical properties. With clay content ≥15wt.%, mechanical properties are further improved but the formation of an apparent superlattice structure correlates with a loss in the electrical properties of the nanocomposite. The use of suitably modified clays in nanocomposites with high clay contents eliminates this superstructure formation, yielding materials with enhanced performance.
Abstract Alzheimer disease (AD), the most prevalent neurodegenerative disorder, causes progressive cognitive decline and degeneration of synapses and neurons. Some neurological impairments in AD may reflect reversible network dysfunction rather than loss of neurons. Biochemical and genetic studies have identified several molecules that may play a causal role in AD pathogenesis. We will review how these molecules impair memory. Many molecules that are important for synaptic plasticity are altered in AD, including receptors, channels, kinases, and neuromodulators. We will discuss how these molecular alterations, as well as cellular and network level alterations, could contribute to deficits in synaptic plasticity and memory.
Track defects and failures resulting from weak strength and buckling cause many of the railroad accidents. One parameter that greatly affects track performance and safety is the track vertical modulus, which is a measure of the vertical stiffness of the rail foundation. Current techniques for track modulus measurement, while accurate, are time-consuming, labor-intensive, require track closure, and provide only single-point information. Ground penetrating radar (GPR) is a non-destructive and non-invasive technology that has shows great potential for imaging subsurface features and assessing the integrity of track substructure. The technique is based on the principles of electromagnetic wave reflection from and transmission through distinct layers of varying dielectric properties. A single electromagnetic pulse of energy at an appropriate frequency is launched into the ground, and reflections from various subsurface layers are recorded in the form of an image. Since studies have shown that the electrical properties of base course aggregates can be used to infer their strength properties, we hypothesize that the information on the track substructure layering characteristics can be used to indirectly infer track modulus. Using a comprehensive set of coincident GPR and track modulus measurements acquired over various types of railroad track geometries, a multivariate linear regression model has been developed. Our analysis reveals a consistent relationship between the weighted average of subsurface 400 MHz GPR reflectivities at specific depths to the measured track modulus with an accuracy of better than approximately 3.4 MPa (500lb/in./in.). The model is thus able to predict track modulus from GPR measurements, and would considerably reduce the time and expense of operational track maintenance strategies.
Cholinesterases (ChEs) have been identified in vertebrates and invertebrates. Inhibition of ChE activity in invertebrates, such as bivalve molluscs, has been used to evaluate the exposure of organophosphates, carbamate pesticides, and heavy metals in the marine system. The golden apple snail (Pomacea canaliculata) is considered as one of the worst invasive alien species harmful to rice and other crops. The ChE(s) in this animal, which has been found recently, but poorly characterized thus far, could serve as biomarker(s) for environmental surveillance as well as a potential target for the pest control. In this study, the tissue distribution, substrate preference, sensitivity to ChE inhibitors, and molecular species of ChEs in P. canaliculata were investigated. It was found that the activities of both AChE and BChE were present in all test tissues. The intestine had the most abundant ChE activities. Both enzymes had fair activities in the head, kidney, and gills. The BChE activity was more sensitive to tetra-isopropylpyrophosphoramide (iso-OMPA) than the AChE. Only one BChE molecular species, 5.8S, was found in the intestine and head, whereas two AChE species, 5.8S and 11.6S, were found there. We propose that intestine ChEs of this snail may be potential biomarkers for manipulating pollutions.
A novel electrochemically exfoliated graphene-molybdophosphoric acid nanohybride (EG-MoPA) was prepared via a simple method. Both scanning electron (SEM) and atomic force microscopy (AFM) results show that MoPA clusters are attached to the surfaces of graphene sheets. By changing the mass ratio of EG-MoPA, the morphology of nanohybrid itself can be significantly modulated, from mostly flat graphene like structure at low amount of MoPA to very uneven, wavy surfaces when MoPA is present in higher concentration. The Raman and Fourier transform infra red (FTIR) spectra in conjunction with electrochemical results indicate that strong interaction exists between the components of nanohybride based on charge transfer and electrostatic interaction of graphene sheets and MoPA. The electrochemical performances are improved by synergetic effect of reversible redox properties of MoPA and the double layer capacitance of a high-surface area of the obtained nanohybrides. The higher current capability of EG was achieved by anchoring the small MoPA concentration on the graphene support. The strong bonding of EG with the MoPA prevents acid to dissolve in the electrolyte upon cycling, enabling the stable capacitance behaviour of the low-doped EG sample. The capacitance for the EG doped with the high amount of MoPA was found to be much larger than for EG. However, the obtained capacitance decreases at the beginning of cycling due to the dissolution of excessive amount of surface MoPA, weakly bonded to the graphene support.
Biopolymer based composites have been employed in numerous applications with increasing interest not only due to renewable, eco-friendly nature, but also because of the flexibility in processing conditions and competitive cost of their end products. The conductive materials from biopolymers have been found applicable in robots, medical imaging, sensitive membranes, actuators, visual displays, electronic wiring and shielding, and components in batteries. Cellulose is one of the most abundant biopolymers in the nature, which has received special attention for development of conducting materials due to biocompatibility for protein and drug immobilization and ability to form the composites with synthetic polymers. The present review is aimed to provide concisely the current status in this field of conducting composites from cellulose, with brief discussions of associated problems and future applications.
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This Corrigendum is retracted because the article that it relates to has now been retracted.
Nano crystallization in tellurium selenite glasses (TeO2-SeO2-Li2O) is achieved by the conventional heat treatment method. The structural phase transformation of glass samples is verified by X-Ray diffraction. The morphology, crystallinity, and the size of crystals were determined by Field Emission Scanning Electron Microscopy. The main crystalline phases detected are Li2Te2O5|α- Li2Te2O5, TeO2, Li2TeO3, SeO2, Li2Te2O5|β - Li2Te2O5, Se. It is found that nanoparticles are agglomerated into a rod-like structure having size in the range of 20–93 nm. Conduction mechanism and relaxation behavior in the present glass system is studied with a function of temperature and frequency. The conductivity is slightly increased from 1.04 × 10−4 to 2.87 × 10−4 Ω−1m−1 as the temperature is increased from 100 to 250 °C. It is observed that the electrical resistance decreases as the Li2O concentration is increased from 10 to 20 mol %. From the modulus spectra, the presence of both grain and grain boundary effect is observed. From the data, the hump is observed around temperature 200 °C in the tested glass system and indicates transition which represents resonance in the glass system due to nano crystalline behavior in the glass matrix. The power law exponent is calculated by fitting the data and suggesting those ideal long-range pathways, diffusion-limited hopping in the glass sample. Based on exponent values, ionic conductivity exists in the glass sample.
Lithium metal (Li) is electrochemically-grown at the lithium phosphorus oxynitride glass electrolyte (LiPON)/copper (Cu) thin film interface. The plated lithium morphology depends on the current densities, and larger current densities bring about smaller-sized precipitation of Li with larger coverage ratio by the precipitates. Both scanning electron microscopy and in-situ optical microscopy observations reveal that the lithium tends to grow at the lithium pre-plated place. Large potential drop was observed at the initial lithium plating process, suggesting that the nucleation process requires large activation energy at the initial lithium plating process at the LiPON/Cu interface. The resultant morphology-controlled in-situ prepared Li provides stable and low-resistive Li/LiPON interface compared with the vacuum-evaporated Li thin film.
Sodium-ion batteries are generating considerable interest for large-scale energy storage systems and electric vehicles. However, high energy density cathodes often show low power due to poor kinetics and rate capability. The primary cause is large ionic radius of Na+ ion that provide high kinetic barrier to Na+−ion transport. The β−NaMnO2 show high discharge capacity but fails to retain long range order during sodium extraction that prevents it from fast charging. Here, we report successful aluminium doping of 4 and 11% to the parent structure to mitigate this problem. The β−NaMnO2 shows capacity retention of only 41% after 35 cycles when cycled at 1C−rate. On the contrary, aluminium doping of 4 and 11% shows capacity retention of about 76% and 80.4%, respectively after 50 cycles. The designed material, β−NaMn0.96Al0.04O2, can deliver a discharge capacity of 139 mAh g−1. These values demonstrate an excellent electrochemical reversibility at high rate. The density functional theory based analysis shows that aluminium doping increases bond length of Mn−O and a decrease bond length of Al−O. This increases the overall volume of the structure and facilitates free access to the sodium ions without significant distortion.
In this paper, a method of designing an optimally arranged solar array for converterless matching to a known linear load is proposed and compared to the classical Maximum Power Point Tracking method. Long-time performance of both methods is examined for three common types of loads under real weather conditions. Test results indicate that only in case of a pure resistive load the Maximum Power Point Tracking-based solar system advantage is undisputed. In case of a load represented by a voltage source with internal resistance, the long term energy productions of the system employing a practical Maximum Power Point Tracking operated converter is on a par or lower than the converterless system energy yield.
Poly(AN-co-GMA-IDA) has been prepared by copolymerizing acrylonitrile (AN) and 2-methylacrylic acid 3-(bis-carboxymethylamino-2-hydroxy-propyl ester) (GMA-IDA). The polymers were mixed with the plasticizer ethylene carbonate (EC) and lithium perchlorate (LiClO4) to form gel polymer electrolytes (GPE). Fourier-transform infrared spectroscopy (FT-IR) has revealed that the GMA-IDA unit can improve the dissociation of the lithium salt. Furthermore, the GMA-IDA can hinder the crystallization of EC, thereby improving the conductivity of the GPE. This has been established by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis. The interaction between GMA-IDA and EC has been confirmed by FT-IR and 7Li solid-state NMR. The maximum conductivity measured in this investigation was 9.75×10−4 Scm−1.
This study investigated metaphor comprehension in the broader context of task-difference effects and manipulation of processing difficulty. We predicted that right hemisphere recruitment would show greater specificity to processing difficulty rather than metaphor comprehension. Previous metaphor processing studies have established that the left inferior frontal gyrus strongly correlates with metaphor comprehension but there has been controversy about whether right hemisphere (RH) involvement is specific for metaphor comprehension. Functional MRI data were recorded from healthy subjects who read novel metaphors, conventional metaphors, definition-like sentences, or literal sentences. We investigated metaphor processing in contexts where semantic judgment or imagery modulates linguistic judgment. Our findings support the position that the type of task rather than figurative language processing per se modulates the left inferior gyrus (LIFG). RH involvement was more influenced by processing difficulty and less by the novelty or figurativity of linguistic expressions. Our results suggest that figurative language processing depends upon the effects of task-type and processing difficulty on imaging results.
In this work, ionic conductivity data as a function of temperature in the pyridinium-based ionic liquids 1-butylpyridinium tetrafluoroborate, 1-butylpyridinium triflate, 1-butyl-2-methylpyridinium tetrafluoroborate, 1-butyl-3-methylpyridinium tetrafluoroborate, 1-butyl-4-methylpyridinium tetrafluoroborate, 1-butyl-3-methylpyridinium dicyanamide, and 1-octyl-3-methylpyridinium tetrafluoroborate, are reported. A comparison of results for this series of ionic liquids has been used to evaluate the influence of the ionic structural characteristic in this transport property. Temperature dependence of experimental values has been fitted by means of the Vogel–Fulcher–Tammann equation, and from their parameters, maximum conductivity and activation energy for conduction have been derived. From conductivity parameters and the glass transition temperature, a detailed analysis has been performed in fragility terms. Finally, the classical Walden rule has been used to classify the ionic liquids depending on the relationship between conductivity and fluidity.
The thermal behavior of three cathode materials for the lithium/sulfur (Li/S) cell, namely – sulfur, sulfur-LiFePO4 (S-LFP) composite and sulfur-LiV3O8 (S-LVO) composite was studied using Isothermal Micro-Calorimetry (IMC) at various discharge rates. A continuum model was used to calculate the reversible entropic heat and irreversible resistive heat generated over the discharge process and the model data was compared to the experimental data to elucidate contributions of reversible and irreversible heats to the overall heat generated during discharge. The reaction enthalpy (ΔHRx) was measured using IMC for each elementary reaction step and in combination with the calculated reversible entropic heat and irreversible resistive heat was fitted against the experimental total heat measurement. The model showed an excellent fit against the experimental data. Further, Accelerating Rate Calorimetry (ARC) was used to study the thermal safety of these three cells. The cell with the S-LVO composite cathode was found to have the highest onset temperature for thermal runaway and also the lowest maximum self-heat rate. Results of this study suggest that S-LVO composite is a promising electrode for Li/S cells.