MTS比色法测定小球藻细胞活性的研究

为探讨MTS法用于小球藻细胞活性快速测定的可行性,研究了小球藻光合作用,细胞密度和温育温度对MTS法测定细胞活性的影响,分析了铜离子胁迫中不同生理状态小球藻的MTS细胞活性值与最大光化学量子产量的相关性.结果表明:MTS能通过小球藻细胞壁在胞内参加反应,反应产物能被检测到,叶绿体光合作用的电子传递及其酶系对MTS测定细胞活性值无影响.MTS细胞活性测定值与藻细胞的密度成线性关系,在37℃时MTS的反应速率加快,同时藻细胞的MTS细胞活性值和最大光化学量子产量的值呈近似的线性关系,故MTS法能够快速便捷地测定小球藻细胞的活性.     

植物叶片电信号的实验测试与特性分析

目的研究植物叶片表面上是否有电信号存在。方法设计了一台生物电信号测试仪,进行实验测试。结果首次发现了叶片表面上存在电信号,信号电压随光强的增加而增大,该信号具有双周期效应,其周期受光强调制,但在长时间离体的叶片上没有发现电信号。结论叶片电信号不仅可作为植物光合作用的重要参数,而且是一种更有效的定量研究光化学反应的新途径。     

Effects of solar ultraviolet radiation on the photochemical efficiency, photosynthetic pigments and biomass production of Spirulina platensis

Effects of solar ultraviolet radiation (UVR) on Spirulina platensis were studied by investigating its photochemical efficiency, photosynthetic pigments and biomass production while exposed to full spectrum solar radiation or depleted of UVR for understanding how and to what extent UVR influences its photosynthe tic physiology and production. It was found that UVR brought about an extra inhibition of photochemical efficiency by 26%—30%. The greatest inhibition of pho tochemical efficiency in S. platensis was observed at noontime, and then recovered to some extent in late afternoon no matter which treatment they were exposed to. The contents of chlorophyll a, phycocyanin and carotenoids increased during initial stage of the exposure, but decreased with elongated exposure. UVR decre ased the biomass yield by about 6%. It indicated that filtering out UVR of solar radiation would raise the productivity of S. platensis, which is an important factor that should be considered in the production.     

SO_2与甲苯的气相光化学反应

用GC和GC／MS,配合IR、NMR等波谱方法研究SO2与甲苯在无氧以及有氧体系中的光化学反应,确定主要反应产物,研究体系的动力学,探讨反应的链式机制．     

五氯酚钠在水体中的光解

旨在探讨各种要素对五氯酚钠光解的影响。室内紫外光照射实验表明，五氯酚钠溶液的浓度，体积，ｐＨ值，受光面积以及光照距离等，均对光解速率、洮解历时或半衰期产生明显的影响。室外太阳光照射试验结果表明，五氯酚钠试样光解受季节影响显著，春季的光解速率常数为冬季值的１０倍。     

CdS光化学修饰介孔TiO2及其增强的可见光催化活性

[目的]提高介孔TiO₂材料的光催化活性。[方法]采用蒸发诱导自组装法(EISA),以四氯化钛和钛酸丁酯为钛源,嵌段共聚物P123(EO₂₀PO₇₀EO₂₀)为模板剂,制备介孔TiO₂。用光化学修饰法将CdS掺进介孔TiO₂中,合成对可见光有较好响应的复合材料,并利用X射线衍射(XRD)、透射电镜(TEM)、原子吸收分光光度法(AAS)和光催化等手段对样品进行表征。[结果]XRD和TEM结果表明成功合成有序的六方介孔材料;AAS确定复合材料中Cd的含量为0.96mg/g;光催化于500 W氙灯下以2×10^-5mol/L次甲基蓝(MB)为模型污染物,结果显示CdS/TiO₂复合材料的可见光催化活性明显提高。[结论]光化学修饰法制备的介孔CdS/TiO₂复合材料可增强其可见光催化活性。     

戊唑醇在水中光解特性研究

以氙灯为人工光源,研究戊唑醇在水中的光化学降解速率。结果表明,戊唑醇在氙灯下的光降解符合化学反应一级动力学方程。试验期间光照度为3 720~4 300 lux,紫外强度59.8~62.4μw/cm2,试验在25±2℃恒温条件下进行。通过试验测得戊唑醇的光解半衰期为29.1 h。     

光化学合成缺位型α－9－硅钨杂多化合物及其性质研究

利用光化学方法合成了一种硅钨杂多化合物．元素分析得到该杂多化合物的分子式为H10SiW9O34·4H2O．通过UV—Vis,IR,XRD,TG—DTA和电化学等方法对化合物进行了表征,并与H4SiW1240杂多酸（记为SiW12）和标准样品α—H10SiW9O34·4H2O（记为α—HSiW9）的性质进行比较研究,结果表明标题化合物为理α-H10SiW9O34·4H2O,是一种三缺位的、具有Kcggin基本结构骨架的杂多化合物．     

Cu纳米粒子的光化学制备及其可逆生长-溶解现象简

采用光化学方法在五水硫酸铜（CuSO4·5 H2 O）的乙二醇溶液中制备了Cu纳米粒子,通过反应过程中的紫外可见光谱（UV-Vis）探讨了反应历程。采用扫描电镜、X射线衍射仪和能谱仪分析了产物的形貌、物相、晶体结构和化学组成,并研究了光化学法制备Cu纳米粒子的反应参数。研究结果证明了反应仅在隔绝空气,紫外光引发的条件下才能发生,发现了生成的Cu纳米粒子敞口静置时会被溶解在胶体中的氧气逐渐氧化,再次在隔绝空气的条件下用紫外光照射后,又会重新生成Cu纳米粒子的现象,并讨论了出现这一现象的原因。而加入三乙醇胺后,同样在隔绝空气,紫外复色光照射的情况下,Cu纳米粒子会优先生长在表面上,采用这种方法,在氧化铟锡（ITO）导电玻璃上制备得到了Cu纳米粒子。     

Smog chamber studies of ozone formation potentials for isopentane

The incremental reactivity and ozone formation potential of isopentane have been studied with chamber experiments and computer simulations. The chemical mechanism used in the computer simulations is an isopentane sub-mechanism from the Master Chemical Mechanism （MCM）. The results from the chamber experiments suggest that the MCM can well simulate i-C5H12-NOx chamber experiments. The heterogeneous reaction of NO2 and water is an important source for OH radicals in the chamber experiments. The photolysis of HONO is responsible for the initiation of isopentane in photochemical reactions. The reaction rate constant for NO2 → HONO was determined to be 3.9×10-4―5.9×10-3 min-1 by conducting 3 sets of CO-NOx-air irradiations. 5 sets of isopentane-NOx irradiations under different conditions were performed in our chamber. Compared with the experiment with a low relative humidity （RH）, an increase in RH can increase the reaction rate of NO2 with H2O, so that the peak ozone occurs earlier. When isopentane is predominant over NOx, the peak ozone concentration is largely dependent on NOx concentrations.