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881.
The monomer 2, 4-dichlorophenyl methacrylate (2,4-DMA) was synthesized from 2, 4-dichlorophenol and characterized by conventional methods. The homopolymers of 2,4-dichlorophenyl methacrylate and its copolymers with 8-quinolinyl methacrylate (8-QMA) in different feed ratio were prepared by free radical polymerization using dimethyl formamide (DMF) as a solvent and 2,2-azobis iso butyronitrile (AIBN) as an initiator. The resulting polymers were characterized by using IR spectroscopy. Reactivity ratios of monomer were evaluated using UV-spectroscopy. Average molecular weights and polydispersity were determined by gel permeation chromatography (GPC). Solution viscosity was also obtained. The thermal analysis was carried out using TGA and DSC. The homo- and co-polymers were also tested for their antimicrobial properties against selected microorganism. The metal ion uptake capacity of synthesized copolymers was estimated by batch equilibration method using different metal ion solution under different experimental conditions. It is observed that due to the presence of pendant ester bound quinoline group, the copolymers are capable of adsorbing cations from their aqueous solution. 相似文献
882.
Jong-Ho Ryu Jong Hyun Seo Jae-Han Jeong Sung-Kap Kim Dong Nyung Lee 《Journal of Applied Electrochemistry》2004,34(9):879-884
A study has been made of the electrochemical etching of 99.99% aluminum foils at a current density of 50 mA cm–2in AlCl3–HCl solutions (1 m Cl–) at 80 °C. The solutions were made by dissolving metallic aluminum into 1m HCl solution, to give a Cl– concentration of 1 m. The number density of etch tunnels and the homogeneity of tunnel length decreased, and the mean pit size and its standard deviation increased with increasing Al3+ concentration. The results were discussed based on potential transients at a current density of 50 mA cm–2, current–potential curves at a scan rate of 10 m Vs–1 and electrochemical impedance spectra. 相似文献
883.
The addition of a small amount of nanoclay (1-3 wt%) can provide excellent volume shrinkage control of unsaturated polyester (UP)/styrene (St)/poly(vinyl acetate) (PVAc) systems cured at room temperature. PVAc serves as the low profile additive (LPA). In this study, both temperature-induced phase separation of the uncured resin mixture and transmission electron microscopy (TEM) of the cured sample revealed that nanoclay resided in the LPA-rich phase, leading to a higher reaction rate and earlier onset of micro-cracking in the LPA-rich phase or at the interface of the LPA-rich and UP-rich phases. Consequently, an earlier volume expansion during curing was observed in reactive dilatometry, resulting in better shrinkage control. On-line measurement of the composite thickness change during vacuum-infusion liquid composite molding [e.g. the Seemann Composite Resin Infusion Molding Process (SCRIMP)] further proved excellent volume shrinkage control of nanoclay filled systems, leading to a smoother composite surface. 相似文献
884.
Junzhe Li Shao-hua Luo Yang Sun Jiayu Li Jun Zhang Ting-Feng Yi 《Ceramics International》2019,45(4):4849-4856
Sodium-substituted LiMnPO4/C/reduced graphene oxide (LNMP@rGO) was synthesized in this study via freeze drying and carbon thermal reduction method with graphene oxide as carbon source. Sodium ion doping is optimized and rGO effects are evaluated by XRD, SEM, TEM, BET, Raman, and electrochemical performance measurements. Well-distributed nanoparticles with average size of ~50?nm are evenly distributed on the surface or intercalation between rGO layers, resulting in a porous ion/electronic conductive network. Compared to 122.3?mA?h?g?1 in unmodified LNMP, the best LNMP@rGO (20?mg rGO) exhibits an excellent initial discharge capacity of 150.4?mA?h?g?1 at 0.05?C at 122.9% of the initial capacity. The capacity retention rate is 95.8% of the initial capacity after 100 cycles at 1?C. Capacity of 101.2?mA?h?g?1 is preserved even at rates as high as 10?C. 相似文献
885.
WO3 membrane-encapsulated layered LiNi0.6Co0.2Mn0.2O2 cathode material for advanced Li-ion batteries
Guowen Song Hui Zhong Yanyang Dai Xiangyang Zhou Juan Yang 《Ceramics International》2019,45(6):6774-6781
Despite Nickel-rich materials have all the advantages of high capacity, long cycle life and low cost, there is still a disadvantage that the capacity decreases rapidly as the number of cycles increases. In order to solve this problem, WO3 was uniformly coated on the surface of LiNi0.6Co0.2Mn0.2O2 cathode materials by wet coating, and its cycling performance was greatly improved with the higher capacity. The coated materials were analyzed by X-ray diffraction(XRD), Scanning electron microscope (SEM), high resolution Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy(XPS). The results showed that the coating thickness was around 3.15?nm, and some tungsten ions were doped into the lattice of the near surface area of the LiNi0.6Co0.2Mn0.2O2 material. In addition, the results of charge-discharge test showed that 1?wt%WO3 coating LiNi0.6Co0.2Mn0.2O2 had the best performance, and delivered a discharge capacity of 140 mAh g?1 (the capacity retention rate is 84.8%) in the potential interval of 2.8–4.3?V at 1?C (1?C?=?165?mA?g?1) after 200 cycles, while the bare cathode material only delivered a discharge capacity of 120 mAhg?1 (the capacity retention rate is 75%). The phenomenon indicates that the WO3 coating plays a role in inhibiting the harmful side reactions between the cathode material and the electrolyte, improving the electrochemical and structure stability of LiNi0.6Co0.2Mn0.2O2 cathode materials. 相似文献
886.
Yannan Zhang Peng Dong Jinbao Zhao Xue Li Yingjie Zhang 《Ceramics International》2019,45(9):11382-11387
The porous Fe2TiO5 particles are successfully synthesized through a facile one step solution combustion method. The Fe2TiO5 negative materials exhibit remarkable electrochemical performance with discharge capacities of 371.4?mAh g?1 at the 100 th cycle, and display promising rate stability with discharge capacities 76.6?mAh·g?1 at a high current density of 3.2?A?g?1. In addition, the mechanism of electrochemistry reaction is illustrated by the CV, raman and EIS measurements, the irreversible capacity mainly causes from the irreversible lithium insertion at 1.8?V. The results indicate that the one step solution combustion synthesis of porous Fe2TiO5 is a promising strategy for developing low-cost and high-performance Ti-based negative materials. 相似文献
887.
888.
A mercaptan-containing resin, DMO-M, with high redox capacity- 6.00 mequiv/g, prepared by reacting mercaptoacetyl chloride with the aminophenol resin Duolite A-7 in free-base form has been used to remove mercury in dilute aqueous solution. The resin has high mercury removal capacity; 1200mg/g. Sodium chloride affects the equilibrium sorption of mercury on the resin. At lower pH values, below 1.76, mercury sorption of the resin was greatly reduced. The sorbed mercury is partially removed by 2 mol/L HCl solution containing 5% thiourea. 相似文献
889.
890.
简述了利用正交试验法等试验方法研制GIS/GCB用耐热型环氧浇注件(HDT=135~150℃)的过程,对所研制出的耐热配方试样的电、机械、热性能进行了测定,试验证明所研制出的耐热浇注件性能符合工作温升为65K的产品要求。 相似文献