亲水醇/盐-水双液相体系萃取赤霉素的研究

由异丙醇/硫酸铵-水溶液组成的醇盐-水双液相萃取体系,可用于植物激素赤霉素的提取。研究了醇盐比、体系pH及赤霉素浓度对萃取结果的影响。结果表明在醇盐比(异丙醇/硫酸铵)为1.5mL/4.3g,体系酸度为pH4.0,赤霉素浓度小于0.064g/L时,赤霉素在该体系的一步提取率可达93.47%,富集倍数为11.36。发酵液中常含的氯化钠和葡萄糖,在最佳实验条件下对赤霉素的提取没有影响。用紫外、红外色谱等方法证实,异丙醇提取的赤霉素结构稳定,纯度高。绿豆发芽生长实验表明,该体系提取的赤霉素生物活性不变。     

异丙醇-水分离技术研究新进展

介绍了萃取精馏法、吸附蒸馏法和膜分离法等用于异丙醇-水分离的新进展,并对这几种方法进行了简单评述,具体分析了各种方法的优缺点,展望了异丙醇-水分离新工艺的前景,认为以乙二醇为萃取剂的萃取精馏技术具有推广价值.     

Study of Acidity of Aerogels ZrO2-SO42− by Isopropanol Dehydration Reaction, Surface Potential and X-Ray Photoelectron Spectroscopy

Sulphated zirconia aerogels, with definite atomic ratio S/Zr and hydrolysis ratio (H = H₂O/Zr) were prepared by the autoclave method. The addition of sulphate ions causes a decrease of the cristallinity of zirconia. XPS results show the O1s photoelectronpeak which could be decomposed in two components for the reticular oxygen of the zirconia framework and for oxygen attributed to the OH groups and/or sulphates groups, and the S2p photopeak characteristic of sulphates species. The Kelvin probe shows that the value of pure zirconia is around 200 mV. This value grows up to 1200 mV for sulphate doped catalysts. The modification of the work function is probably due to the charge transfer from the zirconium to an oxygen species, responsible for the increase of Lewis acidity. The catalysts prepared with hydrolysis ratio of H = 4 exhibit higher activities in the isopropanol dehydration reaction than those with H = 2 in the temperature range 373 K–423 K.     

Significant improving H+/VO2+ permselectivity of Nafion membrane by modification with PDDA in aqueous isopropanol

The modification of Nafion® membranes with poly(diallyldimethylammonium chloride) (PDDA) in aqueous solutions of isopropanol has been investigated. A remarkable decrease in vanadyl ion permeability (by 3.5 orders of magnitude), accompanied by a decrease in proton conductivity sixfold at most, was found for Nafion membranes modified in 30–35 wt% isopropanol solutions providing a high swelling of the membranes. The Bradford reagent has been used for the detection of PDDA on the membrane surface.     

间歇式水热合成制备丝光沸石膜及其异丙醇脱水应用

采用市售廉价大孔α-Al₂O₃管作为基质材料，通过热浸渍法在管外表面涂敷晶种，随后在无模板剂体系下，利用新型的间歇式水热合成法制备丝光沸石膜。对比了传统加热和间歇式加热对丝光沸石膜形貌、结构及渗透蒸发异丙醇脱水分离性能的差异。考察了合成液中Na₂O/SiO₂、SiO₂/Al₂O₃和NaF/SiO₂物质的量之比在间歇式水热合成下对丝光沸石膜的影响。研究结果表明，当合成液中Na₂O/SiO₂、SiO₂/Al₂O₃和NaF/SiO₂物质的量之比分别为0.24、16.7和0.25时，制备的丝光沸石膜渗透蒸发异丙醇脱水分离性能最佳，在75℃下，对异丙醇/水(9∶1，w/w)的渗透通量达5.60 kg·m^-2·h^-1，水对异丙醇的分离因数大于10 000。     

顶空进样气相色谱法测定瑞替加滨中溶剂残留

建立瑞替加滨原料药中甲醇、异丙醇、乙酸乙酯残留溶剂的测定方法。以二甲基亚砜(DMSO)为溶剂,DB–WAX123–7032石英毛细管柱为色谱分离柱,FID检测器,程序升温,氮气为载气。甲醇、异丙醇、乙酸乙酯能得到良好分离,甲醇在29.23~292.30μg/m L范围内有良好的线性,线性相关系数为0.996,平均回收率为103.83%;异丙醇在49.96~499.60μg/m L范围内有良好的线性,线性相关系数r=0.996,平均回收率为105.16%;乙酸乙酯在51.59~515.90μg/m L范围内有良好的线性,线性相关系数为0.996,平均回收率为101.36%。甲醇、异丙醇、乙酸乙酯的检出限分别为0.036,0.213,0.062μg/m L,测定结果的相对标准偏差分别为4.96%,4.52%,4.34%(n=6)。该方法灵敏度高,可用于瑞替加滨原料药中有机溶剂的检测。     

The Novel Formation of Ordered and Varied Silica-Imidazole Complexes from Silicic Acid

Abstract

Fixed quantities of silicic acid in isopropyl alcohol were treated with varying amounts of imidazole in the same solvent, left closed till complexation was complete (～7 days) and the resulting gels on slow evaporation (～30 days) afforded glassy solids, ranging from nodules to tubules, as seen by scanning electron microscope (SEM). In another strategy where soluble oligomers of silica along with monomers can be present and the reaction conditions remaining the same, rectangular cubes of varying sizes were secured. In the view of the significance and potential utility of this novel finding, only duplicate runs, which essentially afforded similar SEM are included here. Elemental analysis established the presence of imidazole in the complexes and their percentage composition was computed using thermo gravimetric analysis (TGA). FTIR showed organics, presence of hydrogen-bonded imidazole, Si?O?Si bonds, and complete absence of Si?O?C bonds. It is suggested that a pattern where hydrogen-bonded imidazole with itself and the polymer, is entombed in the polymerized silicic acid. Domains having such a profile most likely lead to the observed morphology.The present work vastly widens the scope for silicic acid—guest complexation and holds potential to discover a range of silica harboring materials.

GRAPHICAL ABSTRACT      

采用低毒溶剂提取脂质

报道了采用低毒溶剂正己烷／异丙醇从肉制品中提取脂质的方法，对影响提取率的重要因素进行了考察，建立了最佳提取条件；通过对粗提物不同纯化条件的研究，确定了适宜的纯化方法，样品用正己烷／异丙醇（3：2，V／V）混合溶剂取10min，再向粗提物中加入10mL10g/L的Na2SO4溶液洗去非脂成分，获得了与氯仿／甲醇法相近的提取率。测定了6种肉制品的脂质含量及脂肪酸组成。结果与氯仿／甲醇法一致；统计检验表明，两方法间无显著性差异。但本法更加安全、简便，快速。