A study of carboxylic-modified mesoporous silica in controlled delivery for drug famotidine

A series of pure silica MSU and carboxylic-modified MSU materials were prepared. The formation of mesoporous silica materials with terminal carboxylic groups on pore surface was performed by the acid-catalyzed hydrolysis of cyano to carboxylic. Then their potential applications in controlled drug delivery carriers were investigated. Drug famotidine was selected as a model molecule out of the consideration of the terminal amino groups in its molecule. The adsorption experiments show significant adsorption of famotidine on the carboxylic-modified MSU materials. And, the functionalization level of carboxylic groups has been found to be the key factor affecting the adsorption capacities of the modified MSU materials for famotidine. Subsequently, three kinds of release fluids, including simulated gastric medium, simulated intestinal medium, and simulated body fluid, were used to test the famotidine release rate from the carboxylic-modified MSU material. Obvious delayed effect has been observed for the famotidine release from the carboxylic-modified mesoporous silica material under the in vitro assays.     

互通多孔碳/二氧化锰纳米复合材料的原位水热合成及电化学性能

以互通多孔碳（IPC）为载体，水热条件下在碳表面原位反应生成纳米结构的二氧化锰（MnO₂），制备互通多孔碳/二氧化锰纳米（IPC/MnO₂）复合电极材料. 采用扫描电镜（SEM），透射电镜（TEM），X射线衍射（XRD），热重分析（TGA）对其结构进行表征；采用循环伏安法、恒流充放电和交流阻抗对其电化学性能进行研究. 结果表明：生成的MnO₂均匀地负载在碳的表面，形成多层次结构，并且随着温度的升高IPC表面负载的MnO₂由纳米颗粒变为纳米片状结构；MnO₂纳米片具有典型的K-Birnessite 型晶体结构；复合物中MnO₂的含量约为34%（w）. 在100 ℃制备的IPC/MnO₂复合材料在三电极系统中最高比电容达到了411 F·g^-1；随着反应温度的升高,比容量先增长后基本保持不变. 以IPC/MnO₂为正极，活性炭（AC）为负极，1 mol·L^-1 Na₂SO₄溶液为电解液组装成IPC/MnO₂//AC 混合超级电容器，发现IPC/MnO₂电极的电容器其电位窗口从1 V扩展到1.8 V，容量可达86F·g^-1，且表现出良好的电容特性和大电流放电性能.     

一代树状碳硅烷液晶的光化学研究－－端基含12个4－丁氧基氮苯介晶基元

研究了新的含12个丁氧基偶氮苯介晶基元的五代树状碳硅烷液晶D1及偶氮苯介 晶基元化合物M5在氯仿、四氢呋喃、N，N－二甲基甲酰胺、乙醇和苯等溶剂中的量 子产率、反－顺光异构化、光回复异构、反／顺异构组分比、热回复异构及活化能 。D1和M5的光致变色速率常数为10~(-1)s~(-1)，而含同一偶氮基元的光致变色液 晶聚硅氧烷的光致变色速率常数为10~(-8)s~(-1)，因此，液晶树状物D1的光响应 速度比后者快10~7倍。     

互通多孔碳/二氧化锰纳米复合材料的原位水热合成及电化学性能

以互通多孔碳（IPC）为载体，水热条件下在碳表面原位反应生成纳米结构的二氧化锰（MnO₂），制备互通多孔碳/二氧化锰纳米（IPC/MnO₂）复合电极材料. 采用扫描电镜（SEM），透射电镜（TEM），X射线衍射（XRD），热重分析（TGA）对其结构进行表征；采用循环伏安法、恒流充放电和交流阻抗对其电化学性能进行研究. 结果表明：生成的MnO₂均匀地负载在碳的表面，形成多层次结构，并且随着温度的升高IPC表面负载的MnO₂由纳米颗粒变为纳米片状结构；MnO₂纳米片具有典型的K-Birnessite 型晶体结构；复合物中MnO₂的含量约为34%（w）. 在100 ℃制备的IPC/MnO₂复合材料在三电极系统中最高比电容达到了411 F·g^-1；随着反应温度的升高,比容量先增长后基本保持不变. 以IPC/MnO₂为正极，活性炭（AC）为负极，1 mol·L^-1 Na₂SO₄溶液为电解液组装成IPC/MnO₂//AC 混合超级电容器，发现IPC/MnO₂电极的电容器其电位窗口从1 V扩展到1.8 V，容量可达86F·g^-1，且表现出良好的电容特性和大电流放电性能.     

Novel Gel—like Process for Synthesizing Submicron LiaNi0.8Co0.2O2 Powders Used in Lithium Ion Batteries

A novel gel-like process has been developed for synthesizing LiaNi0.8Co0.2O2 powders,using citric acid as a chelating agent. This process improves the homogeneity of constituent cation and enhances their reactivity in the obtained precursor. The results of electrochemical test demonstrated that these materials exhibited excellent electrochemical properties. Its initial capacity reached 181.6 mAh/g and reversible efficiency at the first cycle is about 88.6%.     

熔融碳酸盐燃料电池阳极材料表面改性

选择铌作为合金化元素，通过氟化物熔盐电化学表面合金化的方法对熔融碳酸盐燃料电池阳极材料镍进行表面改性，改性后的阳极材料的耐蚀性能与电催化性能均得到明显的改善。     

Electrochemical characterization of solid materials in volume range I. Chemical effects on the matrix-phase separation

The electrochemical phase isolation (EPI) is described as a preparation method for determining specific precipitations in solid materials in microamounts and microdimensions. Fundamental criteria are examined as a function of the main parameter (polarization current) on the system Fe₃C in a Fe-matrix. The influence of the electrolyte composition on the electrochemical behaviour of the matrix, on the one hand, and of the phase, on the other hand, are investigated and utilized.     

A new anode material LiMoS2 for use in rechargeable Lithium Ion Batteries

The novel applications of molybdenum disulfide in recent research were reviewed, such as in lubricant, catalyst and photoelectrochemical solar cells. Recently, we found that LiMoS2 is a good candidate for new anode materials for lithium ion batteries with high lithium storage capacity.Here, the anode material LiMoS2 was synthesized by a hydrothermal method at 150℃ and the electrochemical characterization as an anode material for lithium ion batteries was examined.put in Teflon-lined stainless steel autoclaves of capacity 40 mL. Distilled water was used to fill the autoclaves to 70 % of the total volume. The autoclaves were maintained at 150℃ for 24 h and then cooled naturally. The resulting dark-gray powders were filled and washed with distilled water,diluted hydrochloric acid and ethanol, successively. The final products were dried at 80℃ for 24 h.The powder X-ray diffraction pattern showed the prepared LiMoS2 was amorphous structure. A test cell using LiMoS2 as the active material was discharged and charged between 3 and 0.01 V with respect to Li metal at a constant current density of C/5 (that is, one lithium per formula unit in 5 hours). During the first discharge, the potential rapidly drops to reach a large plateau at 2.2 V, then slowly drops to the other plateau at 0.8 V, and then continuously decreases down to 0.01V. There is only a plateau at 1.35 V in the subsequent discharge curves. The plateaus of charge potential appear at about 1.9 V.The irreversible loss was 41% in the first cycle. The ratio of discharge and charge is more than 99%in the subsequent cycles. Moreover, the ratio of discharge and charge almost reaches 100% after thedemonstrated that LiMoS2 has a very high capacity and a good cycle-ability as an anode material forlithium ion batteries.     

二芳基乙烯类光致变色材料的合成概述

由于具有多种潜在的应用价值, 光致变色化合物作为高级功能材料的研究在国内外广受关注. 在众多的有机光致变色化合物中, 二芳基乙烯特别是二噻吩乙烯, 由于其具有良好的热稳定性和优良的耐疲劳度而成为这类化合物的杰出代表. 近年来, 有关二芳基乙烯类光致变色化合物的各种合成及性能方面的报道已涉及到信息存储、分子开关、逻辑电路、液晶显示、磁性材料等众多领域. 主要是从有机合成的角度, 对这类材料的合成进行了较为全面的概括, 对各种合成方法分别加以介绍和分析, 对其发展趋势予以探索和展望.     

Selenium in electrolytic manganese as a reference material for the quality control of aluminium melts

Electrolytic manganese is an important alloying element for aluminium and steel melts. It is mainly added to melts of aluminium in the holding furnace as tablets or minitablets (compressed compacts of manganese and aluminium powders). Selenium derivates are usually added during the production of electrolytic manganese, so some selenium is present in the alloys produced when electrolytic manganese is added to the aluminium furnace. Since the selenium contents of many alloys are of concern from health and environmental perspectives, their values should be provided. In this work, a laboratory reference material (LRM) based on electrolytic manganese was produced to assure our routine quality control method, where selenium is analysed by hydride generation followed by optical emission spectrometry with inductively coupled plasma (HG–ICP–OES). Therefore, the present paper describes in detail the preparation procedure for and the results from homogeneity and stability studies performed on electrolytic manganese LRM. For this purpose, a commercial electrolytic manganese lot was selected and the main factors involved in the preparation of the material (pretreatment step, homogenization, bottling and storage) were carefully studied and established in order to guarantee the long-term stability of the LRM. The results obtained showed that the LRM developed was a fit-for-purpose material for the quality control of the routine analysis of selenium.