Separation of di- and tripeptides with solvent extraction and an emulsion liquid membrane

The extraction equilibria of various di- and tripeptides with di-2-ethylhexylphosphoric acid (D2EHPA) were studied at low pH values. The complex extracted to organic phase consisted of one molecule of peptide and two molecules of D2EHPA dimer. The extraction constants of the peptides correlated well with the distribution coefficients of peptides between 1-octanol and water, which is a measure of hydrophobicity. The permeation rates of peptides through an emulsion liquid membrane were examined by using D2EHPA as a carrier, Span 80 as an emulsifier and kerosene as a diluent. The rates varied considerably with peptide type, depending upon the hydrophobicity.     

抗坏血酸对核乳胶性能的影响

文章介绍抗坏血酸对核乳胶灵敏度、灰雾密度及潜影衰退性能的影响，并与日本富士ＥＴ－７Ｂ型乳胶的潜影稳定性能在不同温度和相对湿度条件下作相应比较。     

乳化炸药的高温化学发泡

文中在阐述ＮＨ４ＮＯ３－ＮａＮＯ２－Ｈ２Ｏ发泡体系的发泡机制的基础上，推导出了就获得较低的反应速率ｒＲ和气体生成量ｎ的高ｐＨ值对高温的平衡关系，从而提出了高温发泡技术。     

丙烯酸十六酯的合成及其降凝助滤效果

以丙烯酸和十六醇为原料,在丙烯酸/十六醇摩尔比为1.6,对甲苯磺酸质量分数为1.5%,对苯二酚质量分数为0.6%,反应温度为140℃,反应时间为5 h的条件下,制备了丙烯酸十六酯。结果表明,在上述最佳条件下,产物收率可达92%;在中国石油抚顺石化分公司石油一厂、二厂、三厂生产的0#柴油中,分别加入质量分数为0.5%的丙烯酸十六酯和T-1804降凝剂,前者的降凝助滤效果优于后者。     

坨五站中间乳化层快速增长原因及治理方案

胜利采油厂坨五站高含水(95％)原油化学预脱水中，二级沉降罐内油水相之间的中间乳化层增长迅速，引起了一系列问题。现场调查和大量室内测试结果表明，产生这一现象的原因有：油溶性破乳剂WD-1加入点不合理。有2／3的含水原油在通过油水分离器之后才与破乳剂混合；二级沉降罐进油口伸入油相内，油流的冲击达不到中间层；WD-1对坨五站混合原油中的稠油破乳脱水性能欠佳，不能适应坨五站混合原油组成和含水的变化。针对上述各种原因筛选出了性能更好的一种破乳剂1916。根据确定的几种原因采取了相应的措施：将破乳剂加入点改在3个并联油水分离器之前；将二级沉降罐的进油口移到水相内；改用筛选出的破乳剂1916，结果使中间乳化层的增长受到了抑制。图2表4参2。     

Determination of polymer–polymer interaction parameters using inverse gas chromatography

A modified method is discussed that is based on Farooque and Deshpande's method to obtain polymer–polymer interaction parameters using inverse gas chromatography (IGC) data. In the Farooque and Deshpande method, the ratio of the difference of probe–polymer interaction parameters between two polymers and the probe volume [(χ₁₂ ? χ₁₃)/V₁] is used as the abscissa. In the modified method, the ratio [(?₂χ₁₂ + ?₃χ₁₃)/V₁] is used as the abscissa. Experimental data previously reported for a poly(?‐caprolactone)‐polyepichlorohydrin (PCL/PECH) blend and a poly(ethyl acrylate)‐poly(vinyl propionate) (PEA/PVPr) blend are analyzed. It is found that the slopes obtained by the new method had smaller deviations from the theoretical values than the Farooque and Deshpande method. The standard deviations of both slopes and intercepts obtained from the new method are also smaller. Using the new method, the polymer–polymer interaction parameters obtained from the intercept are negative numbers for the PCL/PECH system and very small positive numbers for PEA/PVPr. Explanations are given for the probe and concentration dependency of the polymer–polymer interaction parameters that are generally observed in IGC studies. A new method for selecting the best probe for calculating the interaction parameter is discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 671–680, 2003     

聚氨酯-聚丙烯酸酯共聚乳液的成膜和性能

通过XPS和接触角测试研究了聚氨酯-聚丙烯酸酯共聚乳液在不同基材上的成膜情况，并对共聚胶膜的耐水性和附着力进行了考察．由于该共聚乳液同时存在着亲水组分和疏水组分，所以它在不同的基材上成膜可导致其膜表面的组成成分不同，因而导致其耐水性和附着力也随基材而异。结果表明，亲水性的聚氨酯组分均富集于胶膜内部，但胶膜底层聚氨酯组分的含量却随基材的不同而不同。在憎水且表面张力较高的基材上，共聚胶膜的耐水性良好；共聚胶膜的附着力在表面张力较高的基材上也良好。     

核壳乳液聚合中甲基丙烯酸用量对印花制品的影响

采用核壳乳液聚合法合成涂料印花粘合剂，考察了甲基丙烯酸(MAC)用量的改变对印花产品的牢度和色光的影响：在核中，当MAC的用量分别为0．0g，0．2g，0．4g，0．6g时，干摩牢度分别为25，2．5 ，3,0，3．5，色光由暗变亮；在壳中当MAC的用量分别为0．0g，0.2g，0．4g，0．6g时，干摩牢度分别为2.5，2．5 ，3．0，3．5，色光变亮，对得色量和鲜艳度影响不大。     

丙烯酸酯聚氨酯紫外固化凝胶生成动力学研究

采用丙烯酸酯聚氨酯和二苯甲酮/安息香乙醚复合光敏剂,对该体系紫外光固化反应的凝胶生成动力学进行分析。用红外光谱定量测定光聚合过程的变化,发现光聚合反应主要是以双键打开,交联为特征的,并得出1408cm~(-1)双键吸收峰随光照时间而变化的关系式:P_(c=c)=0.325 t~(0.135)。临界凝胶点可由双键反应程度与凝胶分数之间关系外推得到,凝胶点后,体系中存在一个凝胶与溶胶之间分配关系,此时凝胶与溶胶共存,凝胶中双键反应程度P_(A(g))>总双键反应程度P_A>溶胶中双键反应程度P_(A(S))。随着凝胶增加,P_A和P_(A(g))逐渐上升,而P_(A(s))下降。此体系的紫外固化实验工作曲线与理论值基本一致。     

超微粒乳剂的制备及量子尺寸效应的研究

本文制备了四种不同粒度的超微粒AgBr照相乳剂,用X射线衍射技术对其粒子的大小进行了测定;观察到乳剂的紫外吸收峰随晶体颗粒的减小表现出逐渐蓝移;本文提出晶体表面的悬键的存在使得纳米晶体的平均键能升高,并对纳米AgBr乳剂的量子尺寸效应进行了解释。