月鳢耗氧率与窒息点的初步研究

对月鳢的耗氧率和窒息点进行了初步研究,结果表明: ( 1)无论是水呼吸还是气呼吸,月鳢的耗氧率均随试验鱼个体增大而降低,随水温或气温的升高而升高; ( 2) 月鳢夜间的平均耗氧率略高于白天平均耗氧率; ( 3) 月鳢的窒息点也是随鱼体增大而降低,随水温升高而升高; ( 4) 气呼吸在月鳢的呼吸活动中占有较重要的位置.     

Pyridoxamine as a multifunctional pharmaceutical: targeting pathogenic glycation and oxidative damage

The discovery that pyridoxamine (PM) can inhibit glycation reactions and the formation of advanced glycation end products (AGEs) stimulated new interest in this B₆ vitamer as a prospective pharmacological agent for treatment of complications of diabetes. The mechanism of action of PM includes: (i) inhibition of AGE formation by blocking oxidative degradation of the Amadori intermediate of the Maillard reaction; (ii) scavenging of toxic carbonyl products of glucose and lipid degradation; and (iii) trapping of reactive oxygen species. The combination of these multiple activities along with PM safety posture it as a promising drug candidate for treatment of diabetic complications as well as other multifactorial chronic conditions in which oxidative reactions and carbonyl compounds confer pathogenicity.Received 1 March 2005; received after revision 25 March 2005; accepted 31 March 2005     

管式臭氧发生元件的分类与特性分析

根据臭氧产业的现状以及发展趋势,对介质阻挡放电管式臭氧发生元件进行了分类,分析了管式元件采用不同结构、不同介电体时对臭氧产生的影响.通过比较不同管式元件的优缺点,对其未来的发展方向进行了展望.     

用EIS研究PEMFC膜电极的运行条件对其性能的影响

在质子交换膜燃料电池（PEMFC）中，采用电化学阻抗谱（EIS）研究了膜电极（MEA）的一些运行条件对其工作性能的影响，并探讨了其作用机理．通过测量数据的解析和等效电路的数学模拟，得到了与MEA结构关联的电极诸参数随电池温度和反应气体压力的变化规律．研究表明，MEA的氧电极的电化学反应电阻随电池温度的升高显著减小，氧电极的双电层电容随电池温度的升高有所增加，表明电极有效面积得以增加，有利于MEA工作性能的提高．     

煤气发生炉气化过程分析与提高煤气品质的技术措施

对煤炭气化过程进行理论分析,阐明了反应温度对煤炭气化过程热效率的影响.根据煤气发生炉的气化特性指标,探讨了影响煤气发生炉气化品质的因素,从煤炭性质、煤炭粒度及饱和温度等方面得出了提高煤气品质的技术措施.     

藤茶多糖组分AGP-3的体外抗氧化活性研究

研究了藤茶多糖组分AGP-3的体外抗氧化活性.用K3[Fe(CN)6]模型测定多糖的还原能力,用试剂盒方法测定丙二醛(MDA)及活性氧(ROS)含量,用分光光度法测定小鼠红细胞溶血和小鼠肝线粒体肿胀度.结果表明,AGP-3在化学模拟体系具有一定的还原能力和清除活性氧能力,一定浓度范围内具有体外清除小鼠血清活性氧的作用,并能减少小鼠肝组织及肝线粒体MDA的生成,可抑制小鼠红细胞溶血和肝线粒体肿胀.     

Cloned pigs derived from somatic cell nuclear transfer embryos cultured in vitro at low oxygen tension

Great progress have been made in animal cloning in China, as evidenced by the live births of cloned cat- tle[1,2], goats[3,4], and sheep[5]. In contrast, pig cloning is still in its infancy though limited fundamental studieshave been conducted[6]. It is g…     

Effects of deposition parameters on the properties of VO2 thin films

The vanadium oxide thin films are deposited for microbolometers by radio frequency reactive sputtering method at room temperature. The effects of the oxygen partial pressure on the deposition rate, electrical properties and compositions of the films are discussed. The as-deposited VO_x thin films with x value of nearly 2 are deposited by adjusting the oxygen partial pressure. After oxidation annealing of these films in air, the VO₂ films with high temperature coefficients of resistivity (about -4%/℃) and low resistivity can be obtained. The square resistances of the films are in the range of 100 kΩ/squ?300 kΩ/squ. All films are deposited at room temperature and annealed at 400℃, in which the compatibility between VO_x deposition process and MEMS (micro electromechanical systems) is greatly improved.     

混凝土氧气扩散系数试验研究

为了确定混凝土材料氧气扩散系数和混凝土水灰比、环境相对湿度及环境温度的关系,根据Fick扩散定律的基本原理,研制了混凝土氧气扩散系数测试装置.利用该装置,进行了上述3种因素对混凝土氧气扩散系数影响效果的正交试验研究.结果表明,环境相对湿度对混凝土氧气扩散系数影响最明显,混凝土水灰比次之,环境温度的影响最后.根据试验结果,利用SPSS统计分析软件得到了混凝土氧气扩散系数和混凝土水灰比、环境相对湿度和环境温度相互关系的预计模型,为钢筋锈蚀的定量评价中合理确定混凝土氧气扩散系数提供了科学依据.     

PWR蒸汽发生器水滴重力分离研究

用分离流动模型模拟了重力分离空间内的汽水两相流动，对重力分离空间内水滴的运动和分离效率进行了数值计算，讨论了重力分离高度和蒸汽上升速度对重力分离效率的影响以及各种尺寸水滴的跟随性