糠醛液相催化加氢反应动力学研究

由糠醛在铜系催化剂上液相加氢动力学的试验数据中计算活化能,并证实了反应速度的大小,在—定条件下与糠醛浓度无关。反应速度正比于氢压的0.55～0.68次方。     

中国南海软珊瑚化学成份研究N—D

从中国南海西沙群岛水胜岛附近海域采集到的一种软珊瑚[Nephthea A1bida(Holm)]中分离到一种新的长链不饱和二羟基酰胺N—IV,熔点85—87℃,分子式C_(36)H_(69)NO_3(M=563),通过对它的IR,MS,UV,~1HNMR,~(13)CNMR及~(13)CNMRDEPT实验等波谱数据分析,推定N—IV的结构为N—1—羟甲基—2—羟基—(EE)—3,7—十二碳二烯基二十三脂肪酸酰胺。     

直链伯醇结构与熔点关系的拓扑化学研究

用拓扑方法探讨了直链伯醇的熔点与分子结构的关系，提出一个结构基础明确的定关系式。对甲醇到１－三十四烷醇的计算结果表明，计算值与实验值的一致性令人满意。应用这一定量关系，不仅能够合理表征直链全醇的结构性能关系，而且有助有助于揭示物质结构与性能关系这间的奥秘。．     

聚乙烯醇回收方法的改进

通过加入少量助凝剂 X,使日本敷岛纺织公司的专利——SSPQ 凝结剂中的盐析剂 Na_2SO_4的用量减少了50%,总投药量减少了38%,而聚乙烯醇的回收率和 COD 去除率分别可达87%和81%,不低于 SSPQ 凝结剂的聚乙烯醇回收率和 COD 去除率。改进后的凝结剂代号为 SSPQ-1号。     

水质稳定剂“PC-602”(多元醇磷酸酯)缓蚀作用机理的研究

“PC-602”是一种具有优良缓蚀作用和一定阻垢作用的高效水质稳定剂。本文对“PC-602”在中性水介质中的缓蚀作用机理进行了研究。用铁氰化钾显色法、AES分析和椭圆仪测量研究了缓蚀膜的组成和生长过程。试验结果表明,“PC-602”在金属表面形成络合沉淀膜和氧化膜等复杂的复合膜。电化学方法测试结果证明,“PC-602”是对电极的阴极和阳极电化学过程都有抑制作用的混合型缓蚀剂。     

冻胶纺PVA纤维的超拉伸研究

通过测定聚乙烯醇(PVA)冻胶纤维的表观拉伸粘度(η)与温度(T)的函数关系,求得了表观拉伸活化能(Ea)。试验表明,PVA 冻胶纤维在不同的拉伸温度区间呈现不同的活化能。当温度为70～135℃时 E_(a1)为5.3～9.2 kJ/mol;135～160℃时 E_(a2)为45～54kJ/mol.应用正交设计试验对拉伸参数进行了选择,在优化的拉伸条件下 PVA 冻胶纤维可实现高倍拉伸(超拉伸)。随着拉伸倍数的提高,纤维的结晶度和取向度提高,但在超拉伸的情况下,二者增加不明显。纤维的抗拉强度则随拉伸倍数的增加而单调增加。在本实验条件下当拉伸倍数为60时,PVA 纤维抗拉强度达11.3cN/dtex,模量达323cN/dtex,远高于湿法成型纤维。     

Enzymatic reduction of fatty acids and acyl-CoAs to long chain aldehydes and alcohols

Summary The properties of enzymatic systems involved in the synthesis of long chain aldehydes and alcohols have been reviewed. Fatty acid and acyl-CoA reductases are widely distributed and generate fatty alcohols for ether lipid and was ester synthesis as well as fatty aldehydes for bacterial bioluminescence. Fatty alcohol is generally the major product of fatty acid reduction in crude or membrane systems, although reductases which release fatty aldehydes as products have also been purified. The reduction of fatty acid proceeds through the ATP-dependent formation of acyl intermediates such as acyl-CoA and acyl protein, followed by reduction to aldehyde and alcohol with NAD(P)H. In most cases, both the rate of fatty acid conversion and acyl chain specificity of the reaction are determined at the level of reduction of the intermediate. The reduction of fatty acids represents the major pathway for the control of the synthesis of fatty aldehydes and alcohols. Several other enzymatic reactions involved in lipid degradation also release fatty aldehydes but do not apear to play an important role in long chain alcohol synthesis.     

The AA and ANA rat lines,selected for differences in voluntary alcohol consumption

Summary The offspring of rats that voluntarily select larger quantities of alcohol are heavier consumers of alcohol than the offspring of rats that tend to avoid it. Such selective breeding, repeated over many generations, was used to develop the AA (Alko, Alcohol) line of rats which prefer 10% alcohol to water, and the ANA (Alko, Non-Alcohol) line of rats which choose water to the virtual exclusion of alcohol. In addition to demonstrating the likely role of genetic factors in alcohol consumption, these lines have been used to find behavioral, metabolic, and neurochemical correlates of differential alcohol intake. Some of the line differences that have been found involve the reinforcing effects of ethanol, the changes in consumption produced by alcohol deprivation and nutritional factors, the behavioral and adrenal monoamine reactions to mild stress, the development of tolerance, the accumulation of acetaldehyde during ethanol metabolism, and the brain levels of serotonin. It is hoped that these studies will lead to a better understanding of the genetically-determined mechanisms that influence the selection of alcohol.     

Sister chromatid exchanges in lymphocytes of normal and alcoholic subjects

The effects of alcohol consumption, cigarette smoking and age on sister chromatid exchangen (SCE) frequency in human lymphocytes were assessed by means of multiple linear regression. An increase in SCE rates was associated with alcohol consumption (p=0.0001), smoking (p=0.0231), and, to a small extent (p=0.057), age. These three confounding factors explain 48% of the inter-personal variation in SCE rates among subjects studied.We are grateful to Dr D. Krapavickaité for performing, the statistical analysis, and to Mrs V. Navickiené for technical assistance. We also wish to thank Dr B. Lambert (Stockholm, Sweden) for his valuable suggestions.     

水含量对脂肪酶促有机硅烷醇酯化反应的影响

水含量对有机相中脂肪酶催化有机硅烷醇与戊酸的酯化反应有显著的影响。脂肪酶Ｌ＿１７５４的最适温度随有机溶剂中水含量的降低而提高，溶剂中的水含量不影响固定化脂肪酶Ｌｉｐｏｚｙｍｅ的最适温度。对所研究的反应体系，水含量为４．１７ｍｍｏｌ／Ｌ时，Ｌｉｐｏｚｙｍｅ的活力最高，而脂肪酶Ｌ＿１７５４的最适水含量为３．０ｍｍｏｌ／Ｌ。