间接竞争ELISA方法测定水中2，4-D的研究

以2,4-D-BSA为包被抗原,采用自行制备的2,4-D单克隆特异性抗体6D11建立了水中2,4-D的间接竞争 ELISA检测方法．本研究比较了包被抗原2,4-D-BSA浓度分别为240ng·mL-1、120ng·mL-1和60ng·mL-1的反应体系和竞争反应时间为60min和15min的间接竞争ELISA剂量-反应曲线,确定了当包被抗原浓度为60 ng·mL-1、竞争反应时间为15min时,剂量-反应曲线的IC50值较低．采用上述实验条件分别测定了由PBS缓冲溶液、饮用水、清华大学地下水和圆明园福海地表水配制的2,4-D标准溶液的剂量．反应曲线,发现实际水样的基质效应对检测结果的影响较大;采用实际水样和PBS缓冲溶液配水在含有5％乙醇的PBS缓冲体系中反应的方法,基本上消除了基质效应对检测结果的干扰．采用上述优化试验条件,测定2,4-D浓度分别为0．5mg·L-1、0．125mg·L-1和0．03mg·L-1的加标样品,测定数据的准确度符合痕量有机污染物定量检测对准确度的要求,但是平行样品测定数据之间的变异系数较大,需要进一步改进检测方法,用于实际水样的检测．     

气相色谱法测定环境空气和废气中乙酸

以蒸馏水吸收环境空气或工业废气中的乙酸,用5%PEG20M+0 5%H3PO4ChromosorbHP80目～100目、2m×2mm玻璃填充柱分离,氢火焰离子化检测器检测,样品直接进气相色谱仪测定。方法最低检出质量浓度为0 16mg/m3,相对标准差为2%～5%,加标回收率在85%～106%之间。方法操作简便、快速。     

Conversion regular patterns of acetic acid, propionic acid and butyric acid in UASB reactor

On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the conversion capacity of the microbe is decided by the substrate characteristic when sole VFA is used as the only substrate. But when mixed substrates are used, the conversion regulations would have changed accordingly.Relationships of different substrates vary according to their locations. In the whole reactor, propionate‘s conversion is restrained by acetate and butyrate of high concentration. On the top and at the bottom of the reactor, conversion of acetate, but butyrate, is restrained by propionate. And in the midst, acetate‘s conversion is accelerated by propionate while that of butyrate is restrained. It is proved, based on the analysis of specific conversion rate, that the space distribution of the microbe is the main factor that affects substrates‘ conversion. The ethanol-type fermentation of the acidogenicophase is the optimal acid-type fermentation for the two-phase anaerobic process.     

2,4-D完全抗原的合成及其免疫性能评价

以2,4-D为半抗原,BSA为载体蛋白,通过EDC的偶联反应条件优化试验,合成了多种结合比的完全抗原,制备了小分子环境污染物的多克隆抗体.结果表明,偶联反应优化步骤是2,4-D、BSA和EDC同时反应,4°C条件下反应18h.偶联反应可以在2,4-D的浓度为10.0～12.0 mg/mL的0.05mol/L的磷酸盐缓冲溶液中进行,反应缓冲体系pH控制在5.4～6.1之间.EDC的加入量低于12 mg时,采用2,4-D和多聚赖氨酸的偶联物为包被抗原.通过balb/c小鼠免疫试验评价结合比分别为6、12、18和25的完全抗原的免疫性能,结果表明结合比为12和18的完全抗原具有很好的免疫原性.其中以结合比为18的完全抗原免疫小鼠获得的抗血清对包被抗原载体的非特异性吸附低于阴性血清,2,4-D特异性血清含量高,适于作为完全抗原免疫小鼠进一步制备单克隆抗体.     

城市污泥中铜锌的化学形态及其去除

利用连续提取法研究了城市污泥中铜和锌的化学形态,结果表明:污泥中铜和锌都以稳定性较好的硫化物及有机结合物、残渣态形式存在,生物毒性较小,通过适当处理后可以安全加以利用;在此基础上,研究了利用乙酸和双氧水去除污泥中铜和锌的适宜工艺条件,结果表明:在室温条件下,在pH值为4的环境中,利用添加H_2O_2的浓度为2mol/L的乙酸溶液,反应时间为4h,就可以将污泥中超过95%以上的铜和锌淋滤去除。     

Effect of cerium on photosynthetic characteristics of soybean seedling exposed to supplementary ultraviolet-B radiation

Effects of cerium （Ce^3＋） on photosynthetic characteristics were investigated by hydroponics under laboratory conditions when soybean seedlings were exposed to two levels of supplementary UV-B radiation. UV-B radiation badly inhibited the photosynthesis in soybean seedling, leading to a reduction in net photosynthetic rate （Pn）, Hill reaction activity, light saturated photosynthetic rate （Ps） and apparent quanta yield （AQY）, as well as the CO2 and light saturated photosynthetic rate （Pro） and carboxulation efficiency （CE）. On the contrary, Ce obviously promoted the photosynthesis of plants by increasing Hill reaction activity, accelerating electron transport and photophosphorylation, and enhancing carboxylation efficiency. For Ce＋UV-B treatments, the values of photosynthetic parameters were still lower than those of the control, but obviously higher than those of UV-B treatment. The results indicated that Ce alleviated the inhibition of UV-B radiation on the photosynthesis in soybean seedling to a certain extent. In correlating of Pn with Hill activity, AQY and CE, we found that the changes of photosynthetic rate were mainly influenced by the regulating effect of Ce on Hill activity and AQY at low level （0.15 W/m^2） of UV-B radiation, but were dominated by the regulating effect of Ce on CE at high level （0.45 W/m^2）. Thus, Ce could regulate many aspects in photosynthesis of soybean seedling under UV-B stress. The regulating mechanism was close related with the dosage of UV-B radiation.     

离子色谱法测定废气中的甲酸和乙酸

阐述了离子色谱法测定废气中甲酸、乙酸含量的方法和步聚。甲酸、乙酸检出限分别为0.02mg/L和0.05mg/L,方法平均回收率分别为92%和95%。本方法分析速度快,所需样品量少,且无需复杂的前处理。     

甲醇燃料发动机排气中的亚硝酸甲酯和硝酸甲酯的分析

为了测定使用甲醇燃料的发动机排气里的亚硝酸甲酯(MeONO)和硝酸甲酯(MeONO_2)含量,建立了色谱分析方法。本方法的最小检测限MeONO为20ppb,MeONO_2为50ppb。对自制的MeONO和MeONO_2进行了质谱鉴定,并对所制备的一定浓度的样品进行了稳定性考察。应用本方法测定了甲醇机排气中的MeONO含量为5ppm—250ppm,MeONO_2含量为<50ppb。     

载体制备方法对贵金属催化剂Ru/ZrO2催化湿式氧化性能的影响

蒸煮处理水合氢氧化锆制备了ZrO20A;将水合氢氧化锆静置过夜制得ZrO2-B;以此两种载体通过初湿浸渍法制得Ru／ZrO2催化剂．在BET测试中,ZrO2-A载体及其相应催化剂的比表面积远高于ZrO2-B载体及相应催化剂．TPR表明Ru／ZrO2-A中Ru的分散性更好,金属与载体的相互作用更为紧密．以苯酚和乙酸水溶液为模拟废水进行催化剂的评价,结果表明,Ru／ZrO2-A无论是在反应活性还是稳定性上均优于Ru／ZrO2-B．     

煤系高岭土插层改性及其对Ca2+的吸附性能

高岭土具有特殊的层片状结构和阳离子交换性,在环境保护领域的应用越来越广。煤系高岭土作为一种具有高纯度和高结晶度的矿物原料,经有机物插层复合后可有效拓宽其应用范围。分别以乙酸铵、乙酰胺和乙酸钾为插层剂,通过液相插层法制备了煤系高岭土插层复合物,用于吸附去除铜离子,并讨论了其吸附效果。同时,采用傅里叶红外光谱、X射线衍射分析、比表面积测定仪和扫描电镜对插层复合物的结构与性能进行了表征。结果表明,煤系高岭土结构有序,结晶程度较高,适用于插层改性。乙酸铵、乙酰胺和乙酸钾可不同程度地插入煤系高岭土的层状结构中,其中乙酸钾插层效果最好。乙酸钾-煤系高岭土插层复合物经乙醇洗涤稳定后,插层率可达44.75%,对铜离子的去除率可达69.07%。插层后,煤系高岭土的层片状结构排列取向发生了改变,由团聚状变为沿c轴方向堆叠,比表面积从9.894 m2/g提高到12.286 m~2/g。相对于Freundlich方程,乙酸钾-煤系高岭土插层复合物对Cu~(2+)的吸附等温式更符合Langmuir方程,表明其属于单分子层化学吸附。乙酸钾-煤系高岭土插层复合物对Cu~(2+)的吸附动力学方程符合准二级动力学模型。