汽车尾气净化催化剂涂层改性研究

汽车尾气净化催化剂的净化转化效果及其耐久性,与催化剂涂层的涂覆量以及涂层和载体的结合强度密切相关.本文研究了几种不同类型表面活性剂对浆料固体含量、涂层涂覆量以及涂层结合强度的影响.研究结果表明,不使用表面活性剂时,30%为最佳的固体含量;在使用表面活性剂的情况下,浆料的固体含量可以提高至35%.非离子型表面活性剂有助于提高催化剂涂层涂覆量,而使用离子型表面活性剂的浆料球磨过程中产生大量泡沫,无法涂覆.使用非离子型表面活性剂的催化剂涂层的结合强度最好.     

保水剂对番茄生长及水分利用效率的影响

在砂与木屑复合基质中加入不同用量的保水剂,测定基质物理性状,并进行不同水分处理条件下番茄盆栽试验,以研究保水剂对番茄生长及水分利用效率的影响。结果表明:在每1 L基质分别加入1、2、4、8 g保水剂时,与对照(未加保水剂)相比,基质持水量分别增加16.35%、34.00%、61.29%和135.16%,容重分别降低3.61%、5.37%、9.42%和14.64%;在水分耗竭试验中,番茄萎蔫天数分别延长13.92%、22.79%、31.65%和45.5%,干物质量分别增加7.90%、21.60%、57.08%、179.50%,株高、叶片数、茎粗、鲜质量也都随保水剂用量的增加而明显增加;在基质相对水分质量分数分别为55%、70%、85%及100%4种处理下的番茄水分胁迫试验中,每1 L基质施用2 g保水剂时,与对照(未加保水剂)相比,水分利用效率分别提高29.93%、28.06%、14.36%、7.42%,株高、生物量也随水分胁迫程度加重而明显提高。     

极端嗜热厌氧纤维素菌的分离鉴定、系统发育分析及其酶学性质的研究

从云南高温温泉、油井等热源地区采集的大量样品中,获得了一株特殊的极端嗜热厌氧纤维素分解菌B2.分离菌株直杆,革兰氏阴性(G-),未观察到孢子,细胞单个或成对出现.菌体大小为0.4μm×(2-4)μm,严格厌氧,生长温度范围50-70℃,最适生长温度65℃.pH范围4-8,最适pH 7.0.在纤维素粉琼脂上菌落直径2-4 mm,乳白色.分离菌株能利用纤维二糖、葡萄糖、蔗糖、松子糖、淀粉、覃糖等作为碳源,分离菌株还可利用纤维素滤纸、纤维素粉、微晶纤维素、纤维素粉MN300和甘蔗渣、水稻秸杆.发酵纤维素产生乙醇、乙酸.在菌株B2的纤维素酶系中,C1酶、Cx酶和β-葡萄糖苷酶的最适温度分别为80℃、80℃和70℃,其比值为1:9:10,同时发现Cx酶具有较高的热稳定性.部分长度的16S rDNA序列分析表明,分离菌株B2与Thermoanaerobacter ethanalicus具有99.8％相似性.分离菌株B2为Thermoanaerobacter属.图5表3参21     

Toxic effects of selenium on marine fish

Ｔｏｘｉｃｅｆｆｅｃｔｓｏｆｓｅｌｅｎｉｕｍｏｎｍａｒｉｎｅｆｉｓｈ￥／ＺｈａｎｇＹｕａｎｘｕｎ（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆＮｕｃｌｅａｒＲｅｓｅａｒｃｈ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆｓｃｉｅｎｃｅｓ，Ｓｈａｎｇｈａｉ２０１８００，Ｃ...     

羟基致死船舶压载水微生物的生化影响研究

试验表明羟基比值浓度达到0．63mg／L左右时，足以杀死压载水微生物。在此浓度下也会引起微生物的糖、脂质、蛋白质、核酸、酶等发生强烈的化学反应。脂质过氧化物含量上升为原来的3倍；总蛋白质减少了33．4％；核酸中RNA、DNA分别减少了46．9％、77．0％；葡萄糖却增加了1倍，羟基破坏了多糖，使之降解为单糖；过氧化物酶含量减少了21．9％；超氧化物歧化酶减少了54．2％；分离微生物后海水中过氧化氢酶、超氧化物歧化酶分别减少了83．1％、33．2％，上述生化试验资料清楚表明了羟基对微生物三大基本分子(核酸、蛋白质、葡萄糖)、抗氧化酶系(过氧化酶、过氧化氢酶、超氧化物歧化酶)以及脂质均有强烈的破坏作用，这也是致死压载水微生物的主要原因。     

产冷适应复合酶菌株Pseudomonas sp.NJ197的选育、发酵条件及酶学性质

从南极普利兹湾深海沉积物中筛选到一株同时产多种冷适应酶的菌株NJ197,细菌学形态鉴定及16S rDNA序列分析表明,该菌株属于假单胞菌属(Pseudomonas).生长特性研究表明,该菌株属于耐冷菌,其最适生长温度为5~15℃.NJ197菌株能利用多种单一的碳、氮源产酶,最适产酶温度为20℃,最高产酶温度为30℃.粗酶液经硫酸铵盐析、DEAE cellulose-52柱层析初步分离纯化后进行酶学性质的研究.该菌株所分泌复合酶中脂肪酶和淀粉酶的活力最高,它们的最适作用温度分别为30℃和35℃,最适pH值分别为9.0和9.5,对热敏感,是典型的碱性冷适应复合酶.Ca2 、Mn2 、Cu2 、Co2 、Fe3 对该复合酶有较为明显的激活作用,而Zn2 、Hg2 、Rb2 、Cd2 、EDTA则能抑制酶活.其中脂肪酶能在高浓度的SDS、CHAPS等变性剂中表现出较好的稳定性.图5表2参21     

标准加入分光光度法测定废水中六价铬

本文将标准加入定量技术运用于分光光度分析中，成功地排除了废水六价铬测定中复杂的基体干扰。     

DEFORMITIES IN CULTURED CHIRONOMUS TENTANS LARVAE AND THE INFLUENCE OF SUBSTRATE ON GROWTH, SURVIVAL AND MENTUM WEAR

Effects of four substrates (shredded papertowelling, coarse sand, fine sand, and silty clay)on growth, survival and mentum wear of Chironomustentans larvae were investigated in thelaboratory. Three categories of mentum wear were defined:minimal, moderate and substantial. Thenumber of larvae with worn mentum teeth did not differ in anyof the four substrates. However, thenumber of larvae with minimal wear of their teeth wassignificantly different among the substrates andwas in the order coarse sand > shredded paper towelling >clay/silt > fine sand. Mentumdeformities were observed in the cultured larvae, presumablybecause of inbreeding and not the effectof treatment. Differences in biomass and survival of larvaeamong the substrates were not significant(p<0.05), however, there was a trend for lower survival inthe sand substrates. These findingssuggest that shredded paper towelling is the most suitablereference substrate. The occurrence ofnatural abnormalities must be considered when using chironomidmouthpart deformities as an index of environmental degradation.     

One independent variable rate equation describing utilization of biodegradable organic matter in activated sludge processes

This investigation aims to represent aerobic utilization of biodegradable organic matter present in wastewater by a rate equation. This rate equation can then be used to develop a substrate utilization (removal) kinetic model for unsteady state activated sludge process. To achieve this objective, theoretical utilization of biodegradable organic matter in batch process and growth pattern theory were studied. Also, experimental data representing removal of organic matter in different types of wastewaters were collected and analyzed for batch and continuous activated sludge assays. A rate equation was proposed to describe the utilization of biodegradable organic matter based on theoretical analysis of batch process. This rate equation was then verified through differential and integral analysis of the experimental data. Furthermore, a substrate kinetic model for batch and continuous processes was developed. The developed rate equation will facilitate the analysis and design of sequencing batch reactor (SBR) technology for biological treatment of wastewater.     

不同种类食细菌线虫对石油污染土壤微生物的影响

通过在石油污染土壤中接种不同种类食细菌线虫,探究土壤微生物活性和多样性的变化.本试验设置5个处理：杀灭线虫土壤（NFS）、石油污染土壤（SP）、在石油污染土壤中分别接种不同线虫,即秀丽隐杆线虫（Caenorhabditis elegans,SPN1）、头叶属线虫（Cephalobus persegnis,SPN2）和小杆属线虫（Rhabditis marina,SPN3）.结果表明,经过168d试验,和NFS相比,SP的土壤基础呼吸和脲酶活性增大,而微生物量碳含量和蔗糖酶活性减小.和SP相比,SPN1、SPN2、SPN3的基础呼吸增大,微生物量碳减少了34.59%~72.48%,蔗糖酶活性增加了15.66%~22.89%.SP、SPN1、SPN2和SPN3的微生物的丰富度（S）分别下降了5.00,7.25,2.50和9.75,Shannon-Wiener指数（H'）分别显著下降了0.18,0.15,0.15和0.23.不同种类的食细菌线虫可通过捕食作用对石油污染土壤微生物活性及多样性产生影响并有种间差异,有利于提高石油污染土壤微生物活性,促进石油降解.