聚丙烯酸接枝聚甲基丙烯酸甲酯共聚物的表面性质及粘度性质的研究

聚丙烯酸接枝聚甲基丙烯酸甲酯共聚物的表面有其特殊性质:水滴在其表面上形成的接触角基本上与其组成无关,而丙烯酸——甲基丙烯酸甲酯无规共聚物的表面接触角却与其组成有密切关系;接枝共聚物在DMF溶液中,其粘度表现出有趣的现象,说明了接枝共聚物在溶液中有微区现象和聚电解质性质     

Pathways for oxidative fuel provision to working muscles: Ecological consequences of maximal supply limitations

The study of metabolic fuel provision and its regulation has reached an exciting stage where specific molecular events can be correlated with parameters of the organism's ecology. This paper examines substrate supply pathways from storage sites to locomotory muscle mitochondria and discusses ecological implications of the limits for maximal flux through these pathways. The relative importance of the different oxidative fuels is shown to depend on aerobic capacity. Very aerobic, endurance-adapted animals such as long distance migrants favor the use of lipids and intramuscular fuels over carbohydrates and circulatory fuels. The hypothesis of functional co-adaptation between oxygen and metabolic fuel supply systems allows us to predict that the capacity of several biochemical processes should be scaled with maximal oxygen consumption. Key enzymes, transmembrane transporter proteins, glucose precursor supply and soluble fatty acid transport proteins must all be geared to support higher maximal glucose and fatty acid fluxes in aerobic than in sedentary species.     

乳清酸的2.5次微分示波极谱法测定

拟定了乳清酸的2.5次微分示波极谱测定新方法.结果表明在0.8 mol/L HCl介质中,乳清酸产生一灵敏的极谱还原波,峰电位Ep =-0.77 V(vs.SCE);其2.5次微分极谱峰峰电流ep″与乳清酸浓度在4.0×10-8～4.0×10-5 mol/L范围内呈良好线性关系(r=0.999 6,n=9),检测限为1.0×10-8 mol/L;13次平行测量4.0×10-7 mol/L乳清酸的峰电流,所得RSD为1.8%.该方法可直接用于测定牛奶中乳清酸的含量.     

北方铜业冶炼厂硫酸系统风机单机运行实践

详细介绍了S1200-16型鼓风机在北方铜业冶炼厂的使用情况，以及S1200-16型鼓风机的结构、技术参数，提出了为确保风机的正常运行所采取的处理措施。     

顺铂与DNA相互作用下的CD谱的测试

本文报导了ＤＮＡ与顺铂相互作用下的ＣＤ谱的测试过程及实验结果，并对作用机理做了初步分析．     

茴香酸乙酯的合成

从茴香油生产茴香醛的废渣、废液中提取副产品茴香酸，合成茴香酸乙酯。对合成条件进行了研究，取得了满意的结果。     

无机离子在硅胶薄层上的色谱行为研究

以甲基异丁基甲酮（ＭＩＢＫ）－甲酸（ＦＡ）为流动相，对一些无机离子在硅胶薄层上的色谱行为进行了研究，得出了无机离子的Ｒ＿Ｆ值与流动相中强极性溶剂甲酸的体积百分浓度Ｃ＿ｐ之间的关系以及所用流动相的溶剂性质参数Ｂ值．利用该流动相体系对部分多元离子混合液进行了分离．     

Changes in glycosaminoglycan sulfation and protein kinase C subcellular distribution during differentiation of the human colon tumor cell line Caco-2

Summary During the spontaneous differentiation (day 5 to day 15 of the culture) of Caco-2 cells, the sulfation of cell layer glycosaminoglycans increased, whereas protein kinase C activity was concomitantly redistributed from the membrane to the cytosol. The protein kinase C activators, 4-phorbol 12-myristate, 13-acetate and 1,2-dioctanoyl-glycerol inhibited glycosaminoglycan sulfation. By contrast, 4-phorbol 12, 13 didecanoate was ineffective.These results suggest that membrane-bound PKC may exert a modulatory effect on glycosaminoglycan sulfation, and this effect is gradually attenuated as Caco-2 cell differentiation progresses.