Vincentandersson4589

Such an innovative approach is promising as it may promote the rational design of high-performance sulfur cathodes.This study presents a new approach for enabling the development of high-performance lithium-sulfur (Li-S) cells by simply inserting a sulfur-infused separator (SIS) between a common S cathode and a Li metal anode. All solid sulfur electrically isolated from the cathode is electrochemically reduced to polysulfides during the first discharge. Notably, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) studies have demonstrated that the S in the separator disappears completely even when the cell is discharged to 2.1 V in the first cycle. The combination of a SIS with a typical S cathode results in the doubling of the areal capacity with superior cycling stability upon comparison with the control cell. This result demonstrates that the introduction of additional active materials, such as elemental sulfur, to a separator is a highly effective method for the fabrication of Li-S cells with a high areal capacity.We studied that hybrid material of two metal component organic framework (Bimetal MOF), containing graphene oxide (GO) as a sulfur immobilizing host was successfully synthesized by hydrothermal reaction. To prove effect of MOF, only GO and ZIF-67 (Zeolitic imidazolate framework) composites were prepared as comparative samples. Field emission scanning electron microscopy (FE-SEM), and Fourier Transform Infra-Red Spectroscopy (FT-IR) were conducted to determine the morphology and micro-structure of the composite. Electrochemical properties were characterized by cyclic voltammetry (CV) and galvanostatic charge-discharge tests were performed by battery tester. Based on these electrochemical experiments, Bimetal-MOF composites showed the better performance than the other samples.The correlations among magnetic properties, synthesis temperature, and composition of FeCo nanoparticles were investigated herein. Fe80Co20 alloy nanoparticles synthesized at different temperatures (383, 393, 403, 413, 428, and 443 K) showed variable compositions and aggregation degrees of the FeCo nanoparticles. Under the optimized conditions of synthesis temperature of 403 K and duration of 1 h, FeCo nanoparticles were synthesized at molar ratios of 91, 82, 73, 64, 55, 46, 37, 28, and 19. The FeCo alloy nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, vibrating sample magnetometer, fourier transform infrared, and network analyzer. With increasing Co content, the extent of aggregation increased. The cobalt ferrite phase was detected under some conditions, and all FeCo nanoparticles showed high saturation magnetization and low coercive forces. The prepared FeCo nanoparticles exhibited high permeability at a high frequency range.In this study, we propose an accurate and simple current-voltage model for an SOI-JLFET based on a solution of the Poisson equation. The model is divided into three regions accumulation, accumulation-depletion, and depletion. The charge density in each region is calculated with the Poisson equation and region-specific boundary conditions, and then the current is obtained by integrating the charge density with consideration of the Vds effect. The proposed model, which was implemented in HSPICE using Verilog-A, was validated using TCAD simulation for various physical conditions such as SOI channel thickness, gate oxide thickness, and channel doping concentration type. According to simulation results by the error rate calculation, our model shows more than 90% accuracy.Nanotechnologies have changed this world in various aspects including the oral medicine. It has been demonstrated that silver (Ag) nanomaterials can exhibit strong inhibition and killing effect on oral bacteria. Furthermore, the Ag nanomaterials have superb antimicrobial activity and nonacute toxic effects on human cells. Previously, the impact of Ag on oral bacteria was demonstrated by experiments. In this work, we applied molecular dynamics (MD) simulations to investigate the influence of Ag nanomaterials on oral bacteria. Firstly, by comparing change of molecular structure of staphylococcal protein A (SPA) with and without Ag, we found that Ag nanomaterials have strong effect on evolution of protein secondary structure of SPA. Secondly, it was observed that Ag has negligible effect on Solvent Accessible Surface Area (SASA) of SPA indicating that the Ag only changed its microstructure. Finally, it was found that the average amount of hydrogen bond in SPA was reduced in the presence of Ag which was origin of antimicrobial activity of Ag. It is believed that the growing interest in dental medicine with nanomaterials would lead molecular dynamics simulations to be an effective method for studying inhibition and killing pathological process of nanomaterials on oral bacteria.Rheological properties have a great influence on mechanical behavior and durability of fresh cement slurry after construction and hardening. For this reason, a series of experiments were carried out in this study to investigate the effects of different nanostructured TiO₂ (NT) contents on rheological properties of nanostructured TiO₂-cement (NTC) composite slurries. Moreover, the microstructure of NTC was analyzed by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Results showed that the shear stress was increased followed by increased NT content. Variation of viscosity with time was divided into initial decline period, initial stable period, growth period and final stable period. During the first two periods, the viscosity decreased first and then increased with increased NT content. Moreover, the viscosity showed a reverse variation during the latter two periods. check details In addition, it was also noted that the reasonable range for NT content of cement slurry was 0%-1.5%.In this paper, hollow carbon microspheres (HCMs) with tunable shell numbers were controllably synthesized by the combination of facile hydrothermal method and etching treatment. The microstructure, morphology and electrochemical performance of HCMs were investigated by X-ray photoelectron, spectra SEM and TEM measurements, and galvanostatic charge-discharge tests. The size of HCMs was uniform and increased with increasing the number of inner carbon shells. Compared to the single-layer carbon microspheres and double-layer carbon microspheres, threelayer HCMs (TLCs) with diameters of 310-360 nm exhibited the highest reversible capacity presenting original discharge and charge capacity of 626.04 and 575.68 mAh·g-1 at 0.1 C. Moreover, the capacitance retention reached to 360 mAh ·g-1 and charge-discharge efficiency was still over 97% after 100 cycles. The superior properties of TLCs can be mainly attributed to their unique three-layer hollow structure which can significantly enhance the pore volume and specific surface area, and thus provides more Li-ions reaction sites and larger contact area between electrodes.