深共熔溶剂-水混合物同步提取红景天苷和酪醇的响应面优化及其分离回收

以深共熔溶剂-水混合物（LAEG40）作为提取溶剂，红景天苷提取率为主要指标，酪醇提取率为辅助指标，在前期单因素实验的基础上，利用响应面法考察了液料比、提取温度、提取时间三个主要因素对红景天中红景天苷和酪醇同步提取的影响。得到的最佳提取条件为: 液料比12.05:1(mL/g)，提取温度60 ℃，提取时间35 min。在此条件下LAEG40对红景天苷的提取率可达到19.3552?0.6604 mg/g，酪醇提取率可达到1.7211?0.0585 mg/g，远高于传统溶剂水、乙醇对红景天苷和酪醇的提取率。为实现LAEG40提取红景天苷和酪醇的回收，进行了大孔树脂吸附分离的研究。经过一系列优化，获得的最佳吸附分离条件为：选用SP-825树脂装柱，每10g树脂上样30 mL LAEG40提取液，洗脱剂选用80 %乙醇，洗脱体积40 mL，洗脱流速1 mL/min，在此条件下红景天苷和酪醇的回收率分别可达60.47 %和85.07 %。     

THE ROLE OF INTERFACIAL PHENOMENA IN A LIQUID-LIQUID REACTION SYSTEM: EXTRACTION OF PROPANOIC ACID BY TRIOCTYLAMINE

The kinetics of extraction of propanoic acid from water to isobulanol by reaction with trioctylamine have been investigated. Mass transfer was modelled by extending the approach used in absorption with chemical reaction, as it is usually done for liquid-liquid reactions. The presence of the amine, however, gave rise to phenomena that cause this method to fail, producing inconsistent results. In order to explain these data, the presence of relevant interfacial phenomena must be supposed.     

发用防晒成分芦荟甙的提取

芦荟甙不仅具有防晒功效,而且还具有润泽、软化头发,防止断发、护发止痒的功效.设计正交实验,用乙醇水溶液回流溶出芦荟甙,用减压蒸馏的方法得到产品,并找出最佳反应条件.用溴水和红外光谱定性分析,证明了所得产品为芦荟甙.将芦荟甙加入洗发香波中,使用效果良好.实验方法操作简单、可行性高,为芦荟的提取研究提供数据.     

催化裂化柴油芳烃抽提生产工艺的改进与研究

利用某种溶剂，从催化裂化柴油中抽提部分重芳烃，以提高柴油的质量。论述了所抽出重芳烃的进一步分离及利用。     

超临界CO2萃取丁香花蕾的工艺研究及对萃取物的GC—MS分析

本文应用超临界二氧化碳技术 ,研究了丁香花蕾的最佳萃取工艺。结合温度、压力、堆积密度、CO2 流量等因素对丁香花蕾提取物的萃出率的影响 ,采用四因素三水平的正交设计 ,得出丁香花蕾油萃取的最佳工艺条件为 :压力30MPa ,温度 4 5℃ ,CO2 流量 10L/h ,低堆积密度。作者还对萃取出的丁香花蕾油进行了GC—MS成分分析     

CLATHRATE HYDRATE FORMATION ENHANCES NEAR-CRITICAL AND SUPERCRITICAL SOLVENT EXTRACTION EQUILIBRIA

Pre-concentration of dilute aqueous solutions by hydrate formation can improve the effective distribution coefficient and selectivity of solvent extraction. Many solvents can serve simultaneously to promote solution concentration by hydrate formation and also to extract non-polar solutes from the resulting concentrated solution. This concept is illustrated for systems with supercritical ethylene and with near-critical liquid carbon dioxide, and its application to conventional solvents is discussed.     

基于灰度化及边缘检测算法的车牌识别技术研究

日益增长的车辆数量给车辆的管理带来前所未有的压力,车辆的智能化、信息化管理问题也愈来愈突出,车牌识别便是解决车辆智能化管理的有效技术手段之一。介绍车牌识别技术体系的整套解决方案,采用MatLab进行程序仿真,运用权值加重法和均值法对所提取车牌进行灰度化预处理,通过局部差分算法实现车牌图像的边缘检测识别。仿真结果表明该技术方案具有较好的可行性。     

COMPUTER-AIDED GRAPHICS OF LIQUID-LIQUID EXTRACTION

An algorithm has been developed and tested for steady-state liquid-liquid extraction, using rectangular coordinates. It is capable of handling common types of stagewise contact, i.e., single stage extraction, multistage cross-current, and continuous countercurrent multistage extraction. The results depend on the nature of the extraction scheme and the extent of separation desired. While equilibrium data for some systems are stored in its data bank, the present portable computer simulator ( LIQEXT) has the flexibility of reading equilibrium data for other systems, as well as overriding stored data

Both design and rating cases can be performed. In the design mode, i.e., given the feed and solvent rates and the outlet concentration, it calculates the number of stages, the exit stream flow rates, and the concentration profile. In the rating ( or simulation) mode, i.e., given the feed and solvent rates, and the number of stages, it computes the exit streams flow rates and compositions, and the concentration profile. In both cases a graphical output of the concentration profile is produced, either on the screen or on a hard-copy plotter.     

Solid extraction of caffeine and theophylline from green tea by molecular imprinted polymers

This paper involves a feasibility study on using molecular imprinted polymers as the sorbent materials in solid phase extraction for caffeine and theophylline from green tea. Two kinds of MIPs, with caffeine-theophylline mixture and pentoxifylline-theophylline mixture as the templates respectively, MAA as the monomer, EDMA as the crosslinker and ATBN as the initiator, were applied to this purpose. Mixture solution of caffeine and theophylline (1 Μg/ ml in acetonitrile) was applied to the solid extraction cartridges following a load, wash and elute procedure with acetonitrile, methanol, methanol-acetic acid (90/10, v/v) as the solvents, respectively. This solid phase extraction protocol was applied for extraction of caffeine and theophylline from green tea. Comparison between the results obtained with the MIPs cartridges and a traditional C₁₈ reversed-phase cartridge was made. It showed that the MIP-based sorbent on the solid phase extraction was comparable with that of C₁₈ material. HPLC analysis using a C₁₈ column (5 Μm, 250× 4.6 mm from Rstech corporation), methanol: water (60 :40, v/v) as the mobile phase at a flow rate of 0.6 ml/min was applied for the quantitative determination.     

用超临界CO2流体从香兰草豆荚中萃取香兰素的研究

研究了用超临界CO2 流体技术从香兰豆荚中萃取香兰素的工艺条件 ,探索了萃取压力、温度、时间对萃取率的影响 ,结果表明 ,超临界CO2 萃取香兰素的工艺切实可行 ,最佳萃取条件是萃取压力为 35 0bar、温度为 4 5℃、时间为 14 0min ,在此萃取条件下每克香兰豆荚的香兰素萃取量为 2 0 .0 5mg ,萃取率为 98.5 %。