三峡库区降雨径流水体中铜、锰、镍、锌、铅含量及分布特征

本文按时段和随机采集了三峡库区降雨径流水体样品，测定了水体中Ｃｕ、Ｍｎ、Ｎｉ、Ｚｎ、Ｐｂ含量，统计结果表明：Ｍｎ、Ｚｎ、Ｐｂ在径流水体中的含量趋于平均，变异系数较小。随产流时间的变化，水体中５种元素的变化规律不明显     

部分水溶性偶氮染料的光催化降解研究

本研究以高压汞灯为光源,系统地研究了１６种偶氮染料在水溶液中的ＴｉＯ２光催化降解。结果表明,这些偶氮染料的光解为一级动力学反应,采用ＴｉＯ２光催化降解方法处理所研究的偶氮染料是可行的,并初步探讨了染料的结构与光解反应表观速率常数之间的关系。     

不同诱导条件对结晶产物形貌特征的影响

在流化床反应器中,以含铜废水为处理对象,重点考察了诱导条件改变对结晶系统运行效率及结晶产物形貌特征的影响。结果表明,进水200 mg/L,进药比([Cu2+]/[CO32-])1:1.2,pH为10.2的条件下,铜离子去除率可接近100%,诱导晶种表面平滑,诱导颗粒生长成致密杆状晶体结构,以碳酸盐为沉淀剂的诱导结晶系统依赖于体系的pH,高pH体系下发生的共结晶现象是影响系统运行的主要原因;随着进药摩尔比的增加,结晶产物由短杆状向球状转化,晶体机械强度显著降低大量破碎,影响出水水质;进药比1:1.2,pH为11的条件下,含铜废水浓度为500 mg/L时,系统去除率可达95%以上,微晶产率低于5%。     

US/UV联用降解荧光增白剂CBW的研究

对超声波、紫外联用技术降解荧光增白剂的反应进行研究，考察了辐射时间、超声功率、pH、H2O2投加量等因素对降解效率的影响。结果表明：荧光增白剂的降解效率受辐射时间影响较大，降解过程符合拟一级反应I提高超声波的功率可提高荧光增白剂的降解率；H2O2的添加，可使溶液中的氢氧自由基的浓度增加，从而提高了荧光增白剂的降解率。在初始浓度为40mg／L，超声功率为500w、pH为9、H2O2的添加量为30mL／L、反应120min的条件下，荧光增白剂的降解率可达95％。     

三峡库区沙坝沟滑坡影响因素分析与稳定性评价

在不同工况下,通过采取不同的岩土体物理力学参数来计算沙坝沟滑坡的稳定系数并分析影响因素,得到影响该滑坡稳定性的主要因素为降雨、地下水作用及人类工程活动,在一定条件下可能成为滑坡失稳破坏的诱导因素。最后为滑坡防治提出一些建议,对滑坡的预测和防护提供依据。     

玉米芯生产单细胞蛋白研究——生产SCP的Candida Boidinii No.2201诱变菌株的筛选

本研究对用玉米芯酸水解液生产ＳＣＰ的ＣａｎｄｉｄａｂｏｉｄｉｎｉＮｏ．２２０１诱变株进行了初步筛选,选出了诱变菌株Ｙ１０８,其产量比原菌种增加２５％左右,达到了２８ｇ／Ｌ～３０ｇ／Ｌ,产品粗蛋白含量为３５％。初步研究表明,利用诱变株Ｙ１０８生产ＳＣＰ有可能成为未来较好的饲料蛋白添加剂     

Arbuscular mycorrhizae enhance metal lead uptake and growth of host plants under a sand culture experiment

A sand culture experiment was conducted to investigate whether mycorrhizal colonization and mycorrhizal fungal vesicular numbers were influenced by metal lead, and whether mycorrhizae enhance host plants tolerance to metal lead. Metal lead was applied as Pb(NO3)2 in solution at three levels (0, 300 and 600 mg kg(-1) sand). Five mycorrhizal host plant species, Kummerowia striata (Thunb.) Schindl, Ixeris denticulate L., Lolium perenne L., Trifolium repens L. and Echinochloa crusgalli var. mitis were used to examine Pb-mycorrhizal interactions. The arbuscular mycorrhizal inoculum consisted of mixed spores of mycorrhizal fungal species directly isolated from orchard soil. Compared to the untreated control, both Pb concentrations reduced mycorrhizal colonization by 3.8-70.4%. Numbers of AM fungal vesicles increased by 13.2-51.5% in 300 mg Pb kg(-1) sand but decreased by 9.4-50.9% in 600 mg Pb kg(-1) sand. Mycorrhizae significantly enhanced Pb accumulation both in shoot by 10.2-85.5% and in root by 9.3-118.4%. Mycorrhizae also enhanced shoot biomass and shoot P concentration under both Pb concentrations. Root/shoot ratios of Pb concentration were higher in highly mycorrhizal plant species (K.striata, I. denticulate, and E. crusgalli var. mitis) than that in poorly mycorrhizal ones (L. perenne and T. repens,). Mycorrhizal inoculation increased the root/shoot ratio of Pb concentration of highly mycorrhizal plant species by 7.6-57.2% but did not affect the poorly mycorrhizal ones. In the treatments with 300 Pb mg kg(-1) sand, plant species with higher vesicular numbers tended to show higher root/shoot ratios of the Pb concentration. We suggest that under an elevated Pb condition, mycorrhizae could promote plant growth by increasing P uptake and mitigate Pb toxicity by sequestrating more Pb in roots.