Involvement of nitric oxide in the signal transduction of salicylic acid regulating stomatal movement

The effects and the relationship between sali-cylic acid(SA)and nitric oxide(NO) on Vicia faba L.stomatal movement were studied.The results here showed that exogenous SA and NO induced stomatal closure,100μmol/L SA induced a rapid and striking NO increase in the cytosol of guard cells.This phenomenon was largely prevented by 2000μmol/L 2-phenyl-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide(PTIO),a specific NO scavenger,and 25μmol/L N^G-nitro-L-Arg-methyl eater (L-NAME),an inhibitor of NO synthase(NOS) in mammalian cells that also inhibits plant NOS.In addition,SA-induced stomatal closure was largely prevented by PTIO and L-NAME.These results provide evidence that guard cells generate NO in response to SA via NOS-like activity,and that such NO production is required for full stomatal closure in response to SA.H-(1,2,4)-oxadiazole-[4,3-α]quinoxalin-l-one(ODQ),an inhibitor of guanylate cyclase,and nicotinamide,an antagonist of cADPR production,inhibited the effects of SA-and NO-induced stomatal closure.It suggests that both cGMP and cADPR might mediate the signal transduction of SA and NO-induced stomatal closure.     

Homocysteine increases the synthesis of adrenomedullin in vascular fibroblasts of rats

Homocysteine (Hcy), a highly reactive sulfur- containing amino acid, is an intermediate product of methionine metabolism. Elevation of plasma Hcy has been widely studied as an independent risk factor for many cardiovascular diseases such as atherosclerosis, thrombosis, etc.[1]. Inherited hyperhomocysteinemia cases usually suffer from occlusion or thrombosis in arteries and large veins before the age of 20. Hyperhomocysteinemia significantly reduces the survival rate[2] and dilatation functi…     

纳米ZnO光催化有机磷农药降解的研究

研究纳米氧化锌对三种有机磷农药的降解情况，考查了催化剂及其用量、光照时间、pH值的影响，结果表明纳米氧化锌能使有机磷农药发生降解。实验结果还表明不同形貌的氧化锌在降解有机磷农药时其效果不一样，网状比粒状所需要时间要短，这可能因为网状的粒径比较小，与降解体系接触空间更大。     

氧化锌催化合成松香甘油酯的最佳工艺条件

本文用氧化锌作催化剂,松香与甘油为原料进行酯化反应,合成松香甘油酯.实验首先通过反应温度、反应时间、醇酸比等单一因素对酯化反应的大致影响.然后采用正交实验法,考虑三个因素,三个水平对产物的影响,得出最佳的反应条件：反应温度为270℃、反应时间为8h、松香与甘油的物质的量比2.5：1.该条件下,产品的酸值为8.94mgKOH/g,酯化率为94.4%.最后,用红外光谱对产品作出相应的分析.氧化锌具有催化活性大,选择性高,不腐蚀设备等优点,适合现代工业的需要,是一种良好的催化剂.     

共沉淀法制备的铁酸锌纳米材料的晶化与晶粒生长行为

采用共沉淀法合成了纳米铁酸锌粉体,并对所制粉体在100~1000℃不同温度下进行热处理,用TEM、XRD等手段对所制备的纳米铁酸锌晶体进行了表征,并对纳米铁酸锌晶体的晶粒生长进行了探讨.结果表明,具有尖晶石结构的铁酸锌纳米晶在共沉淀反应时就已形成,但晶粒的尺寸较小;随着热处理温度的进一步升高,晶粒迅速长大,粒径的尺寸分布在5~30 nm;当热处理温度升至1000℃左右时,晶粒尺寸已达微米数量级.对照TEM和XRD测量结果,表明所制备的铁酸锌纳米粉颗粒为单晶颗粒.     

YSZ包覆NiO阳极的SOFC发电性能(英文)

采用NH3·H2O-NH4HCO3为缓冲溶液,共沉淀法制备YSZ包覆NiO的NiO-YSZ阳极材料,分析了材料的物相和粒径大小。分别以YSZ包覆的NiO、商用NiO/YSZ为阳极,LSM为阴极,制作YSZ电解质支撑的板状固体氧化物燃料电池,进行发电性能比较。以YSZ包覆的NiO为阳极的电池,功率密度高、极限电流密度大。扫描电镜观察表明,YSZ包覆的NiO制作的阳极表面形成了的网状结构。阳极三相界面、孔隙率提高,是电池性能提高的原因。     

静电纺氧化铝纳米纤维研究

采用溶胶-凝胶法,以聚乙烯醇、硝酸铝、水为原料配制出了硝酸铝/聚乙烯醇溶胶-凝胶纺丝液,并通过静电纺丝技术纺制了Al(NO3)3/PVA有机-无机杂化纤维,经高温锻烧后得到了平均直径约为50～250nm无机纳米氧化铝纤维。     

纳米氧化铁的性质及应用进展

介绍了纳米氧化铁的性质及其在生物医学、颜料、涂料、磁性材料和磁性记录材料及催化剂等方面的应用。     

氧化锌纳米线阵列的制备方法

综述近年来氧化锌纳米线阵列制备方法的研究进展状况,包括气-液-固催化剂辅助化学气相沉积法、模板限制辅助生长法、金属有机气相外延生长法以及胶体化学的自组装(组织)法等,并且评价了这些方法的优缺点.     

高温煤气脱硫新技术的研究及应用

通过对自制ZnO粉末脱硫剂的XRD及硫化实验，表明用热分解法制备的脱硫剂较用沉淀法制备的脱硫剂在物相上较好，而且单一的ZnO脱硫剂在脱硫效率及硫容方面均优于加入促进剂（10%澎润土）的ZnO脱硫剂.