相转移催化氧化苊制备苊桐

本文研究了苊在铬酸酐、冰醋酸和相转换催化剂乙二醇存在下苊的氧化反，较温和的条件下高收率地得到了基酮。     

光催化氧化-分光光度法测定巢湖水体中的总氮

用TiO2光催化氧化将巢湖水体中各种化合物含的氮转化为硝酸盐后用分光光度法进行定量测定,同时研究了各种光催化氧化反应条件对氮的降解率影响.结果表明该法的线性范围为0.00-0.35mg/L,检出限为2.55×10-3mg/L.     

Antioxidant and lipid lowering activities of Indian black tea

Indian black tea; CTC leaf and dust, produced by Tata Tea Limited, Kolkata, (India) was studiedin vitro as potential scavenger of oxygen free radicals. Super oxide anions were generated in a system containing xanthine—xanthine oxidase (enzymic system) and by NADH- phenozine methosulphate (non enzymic system). Anions were assayed in terms of uric acid formation and reduction of nitroblue tetrazolium salt, which were shown to be suppressed by tea extracts. Extracts from both leaf and dust also inhibted the formation of hydroxyl radicalsin vitro in the enzymic system comprising hypoxanthine—Cu⁺²—sodium ascorbate and xanthine oxidase and in non enzymic system of deoxyribose—Cu⁺²—sodium ascorbate and H₂O₂ as well as the Cu⁺² induced lipid peroxidation in human low density lipoprotein. Feeding with black tea in normal rats for sixty days increased their antioxidant activity and their liver microsomes were shown to be protected against peroxidation of lipids as stimulated by metal ions with enzymic or non enzymic reactants. Furthermore feeding with tea extracts in normal as well as triton WR—1339 induced hyperlipidemic rats caused decrease in their plasma levels of total cholesterol, phospholipids and triglycerides. The antioxidant and lipid lowering activities of both extracts from CTC leaf and dust tea was comparable and may be due to the presence of natural products like catechin and others.     

铝合金等离子体电解着色工艺的研究

通过对不同电解液成分和浓度的选取，制备氧化和着色兼容的微弧氧化膜。不同种类的电解液所得到的微弧氧化膜层颜色也不同，同种体系中的主要成分浓度的不同是影响生成微弧氧化膜速率和颜色的原因之一。     

改良型卡罗塞尔氧化沟的性能研究

结合水处理实例，分析研究了新型卡罗塞尔氧化沟在脱氮除磷方面的独到之处。结果表明，新型卡罗塞尔氧化沟，脱氮和除磷效果比常规的处理工艺要好。     

用共价键的均裂和异裂法计算有机物各原子的氧化数

应用Lewis的结构式,采用共价键的均裂和异裂方法,计算有机物分子中各原子的氧化数,方法简单,容易计算.     

Synthesis of 3-O-Benzoyl-1,2- O-isopropylidene-α-D-allofuranose and Its Dimesylated Derivative

Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex.Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose (3). The yield of 3 increased by 8% than that with only oxidated product as reduction substrate. Benzoylated derivative of 3 was selectively hydrolyzed and dimesylated to synthesize 3-O-benzoyl-1,2- O- isopropylidene-α-D-allofuranose (5) and its dimesylated deriva tive respectively. The overall yield of 5 from 1 was 36%. Each step and final products were anal yzed by 1H-NMR spectra and other methods. The experiments showed that the influence of acetic acid concentration on selective hydrolysis was obvious. The hydrolysis yield was 81.8%. Oxidation, reduction and other procedures were practical and had application potential.     

GH4169镍基高温合金高温多轴低周疲劳性能

利用薄壁管试样,在MTS809疲劳试验机上对GH4169镍基高温合金进行了650oC下的高温多轴拉扭低周疲劳试验,通过对应力应变迟滞迴线分析发现,拉扭分量应力应变迟滞迴线形状与试件的加载波形和加载路径相关,塑性应变不断增大。利用FEI-Quanta 200扫描电镜和EDAX Genesis 2000 X-射线能谱仪对试样疲劳断口微观分析,结果表明,GH4169镍基高温合金材料在高温循环加载下有氧化现象。综合不同等效应变下材料的断口形貌差异,推断在高温循环加载下有蠕变氧化作用。     

显色性、色温和白平衡理论及其应用研究

分析了显色性、色温和白平衡理论及在电视摄像实践中的应用,对应用中存在的问题,进行了定量或定性的探讨.     

阳极电催化剂在直接甲醇燃料电池的应用

直接甲醇燃料电池以燃料甲醇来源丰富，价格低廉，储存、携带方便而成为近年的研究热点。本文评述了阳极催化剂在直接甲醇燃料电池的研究概况，详细介绍了多种催化剂对甲醇氧化的作用。