batterydata/paper-abstracts huggingface dataset:
KMn8O16 nanorods were prepared for the first time by a rheological phase reaction method, using KMnO4 and Mn(CH3COO)2·4H2O as reactants. The KMn8O16 samples annealed at different temperatures were characterized by X-ray diffraction, transmission electron microscopy, and galvanostatic charge/discharge profile measurement. The KMn8O16 nanorods annealed at 400°C show the highest reversible discharge capacity (153.8mAh/g even after 50 cycles) at current density of 50mA/g and the best cycling stability. The annealed nanorods exhibit the superior electrochemical performances compared to the unannealed sample, which is confirmed by the AC impedance measurements. These results indicate that the KMn8O16 nanorods could be a promising cathode material for lithium ion batteries.
With the rapid development of wearable electronics like artificial e-skins and smart patch, harvesting biomechanical energy and realizing self-powered sensing are of essential importance for achieving sustainable and efficient function of the system. Here we report a flexible hybrid device that can be conformally attached on soft surface like human skin to harvest diversity touch energies based on electrospun nanofiber mat. Facilitated by the working mechanisms of triboeletric and piezoelectric, the device can generate maximum peak power up to 84μW/cm2 and 0.11μW/cm2 for the TENG and PENG part when stimulated by a compressive stress, which can enhance the energy harvesting efficiency and expand its application areas. By virtue of the high sensitivity of the piezoelectric nanomaterial, the device can also be attached on different parts of body for real-time monitoring the human physiological signals such as respiratory information and radial artery pulse, which shows potential value in self-powered e-skins and healthcare monitoring systems.
This study examined whether physical activity improves spatial perception and attention in early childhood. A pre–post intervention trials design with intervention and control groups was implemented. Participants were 123 kindergarten children, divided into three groups: experimental—orienteering, experimental—dance, and control—no intervention. Instrumentations: attention measured by the MOXO-CPT, a computerized test, and The Cognitive Modifiability Battery Reproduction of Patterns measured spatial abilities. Measurements were conducted pre- and post-interventions. Results showed fast improvement from pre- to post-intervention, achieved simultaneously in both EFs for the experimental groups only. No differences were found between boys and girls. It was concluded that in order to successfully achieve the required tasks, an integration of physical and cognitive skills is needed.
The purpose of this study is to examine the effect of the source of media imagery on participant cynicism toward the police and explore the relationship between media source and the severity of sanctions imposed on police as a result of the portrayed actions. Participants (N = 93) completed a semantic differential scale measuring participants’ attitudes toward members of various occupations followed by a survey to measure baseline cynicism. Then, participants viewed a video of police behavior which was manipulated according to media source and completed a second cynicism measure and demographic survey. Participants were then asked whether to impose a sanction on the police officers. Results indicated that there were no differences in cynicism between groups prior to viewing the video; however, there were statistically significant differences in cynicism between groups after exposure to Citizen Video Journalism (CVJ) from different media sources revealing that cynicism was greater with the group that viewed CVJ from the social media source than from the broadcast media source. Furthermore, results indicated statistical significance between groups and severity of sanctions imposed on police after CVJ video exposure.
To investigate the effects of binder materials on the electrochemical properties of Fe2O3 electrodes in alkaline solution, four different materials were applied as binders: polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyethelene (PE), and poly tetrafluoroethylene-co-vinylidene (P(TFE-VDF)). In KOH aqueous solutions, electrodes containing different binders showed quite different properties. The PE-containing electrode showed the highest capacity retention up to 14 cycles (330mAhg−1, 82.7%). However, capacity fading was observed subsequently, and only 24.6% capacity remained after 30 cycles. In contrast, the PTFE-containing electrode showed continuous capacity fading but the best capacity retention of 38.6% after 30 cycles. Comparing the amount of dropout Fe2O3 from electrodes after charge/discharge measurements, it was reasonable to find that the electrodes with better cycling performance showed less Fe2O3 dropout. When K2S additives were applied, both the electrodes fabricated with PTFE and PE showed superior cycling performance, which was attributed to the good stability of PTFE and PE binders. However, when the effect of the K2S additive on the Fe2O3 dropout was studied with PTFE-containing electrodes, heavier Fe2O3 dropout was observed in the K2S-added electrolyte. This indicated that Fe2O3 dropout was not a dominant factor for the capacity fading of the electrodes.
This is a study of the electrochemical corrosion behavior of aluminum alloy Al7075 and its corrosion inhibition using l-glutamine in 3.5% NaCl solution under different hydrodynamic conditions. The hydrodynamic conditions were simulated by using a rotating disc electrode. The results showed that an increase in rotation speed leads to a higher corrosion current density, while the charge transfer resistance decreases and corrosion potential shifts toward more positive values. The inhibition efficiency depends on rotation speed. That is, the efficiency was low in stagnant solution, but enhanced significantly under hydrodynamic conditions. The phenomenon was attributed to the increased mass transport of inhibitor’s molecules to the electrode surface that is advantageous for improvement of inhibition efficiency. However, higher rotation speeds (Ω ≥ 1,500 rpm) cause a slight reduction of efficiency due to higher shear stresses.
Generally, the capacity of lithium-ion batteries (LIBs) will fade gradually during cycling especially under large current densities because of the structural collapse of electrode materials. Herein, dramatic and favorable electrochemical performance enhancement was observed in a simply achieved MnO nanowire/graphene composite during long-term cycling when utilized as the anode material for LIBs. Characterized by high-resolution transmission electron microscopy, X-ray diffraction and Fourier-transfer infrared spectroscopy, the MnO nanowires were gradually collapsed to nano-spindles and further nanoparticles but these newly formed nanoparticles are still stably anchored on the graphene lamellas. Correspondingly, the specific capacity of the MnO nanowire/graphene electrode exhibited a significant enhancement with a durable life after a slight decrease in the first several cycles. The reason for the self-enhancement could be ascribed to the strong interphase interaction between MnO and graphene flakes. Our work provides a new understanding and insight for the electrochemical behavior of composite electrodes in LIBs and is helpful for the fabrication of high-performance anode materials.
Na2FePO4F encircled by a nanolayer composed of a conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), is prepared using a simple low-temperature process, and X-ray diffraction analysis indicates that the Na2FePO4F–PEDOT composite is the pure phase without any impurities. The existence and uniform encapsulation of PEDOT on the surface of the Na2FePO4F particles are clearly confirmed through Fourier-transform infrared spectroscopy and transmission electron microscopy. The PEDOT coating results in remarkably enhanced electrochemical performance compared with that of pristine Na2FePO4F. At C/5 (1C = 124 mA g−1), the Na2FePO4F–PEDOT composite retains a specific capacity of ∼123.1 mAh g−1, which is close to its theoretical capacity. Even at 10C, the Na2FePO4F–PEDOT composite delivers a capacity of ∼76.1 mAh g−1, which is ∼10 times higher than that of pristine Na2FePO4F under the same conditions. Furthermore, the Na2FePO4F–PEDOT composite maintains ∼70% of its initial discharge capacity over 700 cycles at 1C.
The salt PhSCF2CF2SO3Li appears promising for lithium-polymer batteries. Its poly(oxyethylene) complexes, although less conductive than lithium imide complexes, provided cationic transference numbers ranging between 0.45 and 0.5, enabling high cationic conductivities to be obtained. Thanks to its double substitution by aryl and perfluorinated moieties, the thioether function is stable enough to be used with positive electrodes, such as vanadium oxide and perhaps cobalt oxide.
Lithium plating is a common problem for charging in high-rate and low-temperature Li-ion battery applications. The current “standard anode” material graphite is especially susceptible to the formation of lithium metal on its surface instead of intercalation. In order to improve the understanding of this phenomenon, this investigation was conducted using pulse-relaxation experiments, scanning electron microscopy (SEM) and optical in-situ microscopy. For that purpose, current pulses up to 10 C were applied on graphite half-cells to induce plating on the anode's surface. The resulting characteristics (e.g., cell voltage and changes in surface morphology) were analyzed during pulses and subsequent relaxation. Several characteristic attributes could be detected whenever lithium plating occurred: i) a prominent kink of the voltage transient during charging, ii) a distinctive plateau in the subsequent relaxation of the cell voltage, iii) a gray deposit covering the anode surface which under high magnification shows iv) a net-like structure covering the carbon particles. These attributes may provide useful detection tools for Li plating. The observed characteristics for Li plating were explained regarding the involved microscopic processes. This model was used to understand dissolution of plated lithium on the particle surface after the charging pulse and could thus be confirmed by SEM investigations.
We present a contact lens-like platform that is wirelessly powered by an external coil embedded in eyeglasses via magnetic resonance coupling at 13.56 MHz. The platform is composed of a transparent parylene film as a host substrate, an embedded spiral inductor as a power receiving coil, and metal interconnects for additional electronics. A multilayer thin-film parylene packaging process is used to meet the form factor of a contact lens. A 36 μm-thick metal plating technique is employed on a parylene film to enhance the quality factor (Q) of the receiving coil (Q = 27.3 at 13.56 MHz). The power transfer method and techniques to compensate for coil misalignment are demonstrated on a pig eye, achieving a power transfer efficiency of 17.5 % at a 20-mm powering distance. The effect of tissue on the coil and the power transfer efficiency is examined. The high power transfer efficiency along with the wearable prototype demonstrated herein make promising progress toward smart contact lens in ocular diagnostics.
Lithium batteries with hybrid cathodes of Ag2V4O11 and CF x have been developed that combine the best features of both cathode components. They can offer power density and energy density that are competitive with or superior to other developed battery chemistries, along with the stability and reliability needed for implantable medical applications. More than 100,000 have been used in human implants since introduction in 1999.
Novel multi-component molten salt systems containing iodides, LiF–LiBr–LiI, LiF–NaBr–LiI, and LiF–LiCl–LiBr–LiI, were investigated for use as electrolytes in high temperature molten salt batteries to improve the discharge rate-capability. The iodide-based molten salts showed higher ionic conductivity (∼3Scm−1 at 500°C) than conventional LiCl–KCl, and had low enough melting points (below 400°C) that can be used in practical high temperature molten salt batteries. The iodide-based salts showed instability at temperatures higher than 280°C in dried air. The decomposition mechanism of iodide-based molten salts was discussed, and it was found that elimination of oxygen from the environment is effective to stabilize the iodide-based molten salts at high temperatures.
The Wisconsin Card Sorting Test (WCST) is the gold standard in the evaluation of executive dysfunction (ED) in patients with temporal lobe epilepsy (TLE). We evaluated 35 children with TLE and 25 healthy controls with the WCST and with a more comprehensive battery. Among the children with TLE, 77.14% showed impairment on the WCST. On other tests (Wechsler Intelligence Scale for Children—Digit Forward, Matching Familiar Figures Test, Trail Making Test, Word Fluency, Finger Windows, and Number–Letter Memory), impairment was demonstrated in 94.29%. The authors concluded that the WCST is a good paradigm to measure executive impairment in children with TLE; however, it may be not enough. Evaluation performed only with the WCST not only underestimated the number of patients with ED, but also missed relevant information regarding the type of ED.
The ZnO samples coated with carbon are successfully synthesized by using a high energy ball milling method. The scanning electron microscopy (SEM) images and energy dispersive spectrometer (EDS) spectra of the carbon-coated ZnO and pure ZnO show that the carbon-coated ZnO (carbon source: glucose, citric acid) samples and the untreated ZnO sample have similar particle size and crystal form. The particles have prismatic microstructure whose sizes are about 100–200nm. However, the carbon-coated ZnO (carbon source: sucrose) sample has become agglomeration after calcination whose size has been increased to 2–6μm. The uncoated ZnO powders have more complete crystal shape and they are glazed quadrangular materials, while the carbon coated ZnO particles has a rough surface, which resulted from the growth of carbon coating on ZnO particles. X-ray diffraction (XRD) patterns of the carbon-coated ZnO and the pure ZnO show carbon formed on the surface of ZnO is amorphous. Tafel plot, cyclic voltammetry (CV), AC impedance spectroscopy and galvanostatic charge–discharge measurement are utilized to examine the electrochemical performances of the carbon-coated ZnO. The carbon-coated ZnO (carbon source: glucose) have the most positive steady-state potential and lowest corrosion current density in the zinc electrodes which indicates that it has a good anticorrosion ability. A lower charge platform and a higher discharge platform of carbon-coated ZnO indicate that it have a better charge/discharge performance as anodic material for Ni/Zn cells. A smaller ohmic resistance and charge-transfer resistance imply that the carbon film upon ZnO could greatly decrease the impedance of the reaction process. Meanwhile, the carbon-coated ZnO also showed more excellent cycling performance than pure ZnO. The reason of improvement about electrochemical performance can be ascribed as the unique structure of amorphous carbon layer.
Boron-doped Si particles were prepared by high-energy ball-milling of pure B and Si in various proportions (0, 1020, 1021, 1022 and 1023 atoms B per mole Si). Despite the fact that only a fraction of the added B atoms were incorporated into the Si lattice, a significant decrease of the Si electrical resistivity was observed, leading to a minimum electrical resistivity of 0.13Ωcm for the sample milled with 1021 atoms B per mole Si compared to 190Ωcm for the boron-free sample. Electrochemical investigations focused on these two samples showed that the B-doping of Si does not improve significantly the performance of the composite Si-based electrode for Li-ion batteries in terms of cycle life, coulombic efficiency and high-rate chargeability. Through an analysis of anodic polarization curves, it was also shown that the delithiation reaction is mainly controlled by the Li-diffusion kinetics from a rate of ∼4C on both electrodes. Lastly, it was shown that the use of a resonant acoustic mixer for the mixing of the (Si+carbon black+carboxymethyl cellulose) components increases the cycle life of the composite electrode.
Electrochemical polarization of a crystalline, polymeric or nanoporous system or a single molecule may change the density of charge carriers in a controlled way, and hence the optical and electrical properties. If the system has two contacts, its electronic conductivity can be measured in situ as a function of the charge carrier density that is varied by the electrochemical potential. This is called electrochemical gating. Such investigations can reveal the nature of the charge carriers (mobile or localized) and the mechanism of electronic conduction. Here, we present a brief review of a number of systems including inorganic crystals, polymers, nanoporous quantum-dot solids, and single molecules for which electrochemical gating was used successfully in the study of the electronic properties.
Technology to harvest electrical power from waste micro-mechanical energy is increasingly in demand. A promising approach lies in manipulating the electrical double layer on hydrophobic surfaces; however, the underlying mechanism is still unclear. Here, we demonstrate that ascending air bubbles in water can produce electrical power in a mode similar to other systems that use descending water droplets. Although the two systems, which are analogous to electrons and holes in semiconductors, are similar in fundamental principle, their detailed electrification mechanisms are significantly different. In the air bubble system, only the pre-existing charges on the surface are involved. However, electrification in the water droplet system is dominated by triboelectric charges accumulated on the surface over time. An air bubble can produce a maximum of nine times more energy than a water droplet due to its advantages in terms of its geometry, hydrodynamics, and electro-circuitry. We also suggest an innovative approach to improve energy-harvesting efficiency using artificially embedded charges.
The purpose of this study was to identify an endometrial cell line that maintained the E2 up-regulation of estrogen receptor (ER) mRNA by enhanced message stability and to assess its dependence on ER protein. Estradiol (E2) effects on gene expression were measured in three cell lines: one immortalized from sheep endometrial stroma (ST) and two from human endometrial adenocarcinomas (Ishikawa and ECC-1). E2 up-regulated ER mRNA levels in ST and Ishikawa cells, but down-regulated ER mRNA levels in ECC-1 cells. E2 up-regulated progesterone receptor (PR), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), and transforming growth factor-α (TGF-α) in both Ishikawa and ECC-1 cells. The selective estrogen receptor modulator ICI 182,780 antagonized the E2-induced up-regulation of ER and/or PR mRNA levels in all three cells, while another, GW 5638, antagonized the up-regulation of PR mRNA in Ishikawa and ECC-1 cells. In mechanistic studies, E2 had no effect on ER mRNA stability in ST cells and it destabilized ER mRNA in ECC-1 cells. Thus, Ishikawa cells appear to be the most physiologically relevant cell line in which to study the up-regulation of ER mRNA levels by enhanced mRNA stability. Its antagonism by ICI 182,780 reveals that ER protein is involved in this E2 response.
Combined heat and power (CHP) generation is a fundamental practice to reduce primary energy consumptions and mitigate the related greenhouse gas emissions. Cogeneration plants are even more important in the Hospital sector, as they give the opportunity to operate regardless of the electric power grid, so ensuring energy availability also during grid faults while providing significant cost savings to the public healthcare system. The integration of a battery energy storage with the CHP system could further increase the expected advantages by enabling more flexible operating strategies, further energy reliability and lower operating costs. Therefore, this research paper addresses the development of a specific methodology for the energetic and economic assessment of a grid connected CHP plant assisted by a battery energy storage. More specifically, an evaluation algorithm has been developed and then coupled to a genetic evolutionary algorithm. Then, a vector optimization problem has been solved to find the optimal configurations of a modular cogeneration plant (i.e. size and number of CHP gas engines; battery size) which maximize the primary energy saving while minimizing the payback period. Results based on electricity and heat demand of a hospital facility demonstrate how the battery energy storage system allows the shifting of the Pareto frontier towards better economic results if compared with Pareto solutions found when the optimization problem does not consider a battery storage supporting the CHP plant. The proposed methodology provides an effective and flexible procedure for the optimal configuration and detailed analysis of CHP plants integrated by an electrochemical based energy storage system. In fact, the effects of a high number of interacting energetic and economic parameters are considered together with the technical constraints required to extend battery lifetime in real applications.
A highly active non-platinum group metal (non-PGM) catalyst derived from iron and 4-aminoantipyrine precursors was synthesized using a sacrificial support method (SSM) to obtain a highly porous, open framed structure. The ratio of iron to 4-aminoantipyrine had been previously optimized to catalyze the reduction of oxygen in both acid and alkaline media. In this study, the mechanism of the reduction of oxygen in both media was investigated, and it was found to follow the 2×2 pathway. On its face, electrochemical analysis seems to suggest that the direct 4 electron transfer pathway is favored due to the low peroxide yield, but a closer examination reveals that the 2×2 pathway is followed, where the fast step is the partial reduction to peroxide, and the ensuing reduction step to water is also fairly rapid.
Increasing specific energy of lithium ion battery cells (LIBs) and their cycle life requires deeper understanding of complex processes taking place during the cell operation. This work focuses on the electrode potential development and the interactions between negative and positive electrode in a quasi LIB full cell by applying over-discharge conditions. By analysis of the potential profiles, a characteristic potential plateau at ≈ 3.56 V vs. Li/Li+ was detected at the graphite negative electrode, which can be assigned to the Cu oxidation process of the negative electrode current collector. Also at the positive electrode, a time shifted potential plateau was observed, which could be attributed to a competitive reaction between conventional discharge (lithiation) and parasitic Cu reduction (plating) on the positive electrode surface. The proposed mechanism involving the presence of elemental Cu on the positive electrode surface was confirmed by SEM-EDX mapping experiments. The relevance of Cu dissolution and deposition as well as possible solution approaches are discussed.