石墨炉原子吸收法测量PM10中铅的不确定度评定研究

根据检测步骤和测量模型,以及测量不确定度评定与表示方法,分析了石墨炉原子吸收法测定环境空气PM10中铅不确定度的主要来源,量化了采气体积、切割粒径、标准溶液浓度与校准曲线拟合、量器容积误差、测量重复性等不确定度分量.考察得出采样流量是不确定度主要因素.用合成标准不确定度和扩展不确定度对测量结果进行表述.研究内容为该方法测量不确定度的评定提供参考.     

高炉旋风灰作为自产喷吹煤粉添加剂的相关研究

为了提高高炉干法除尘布袋的寿命,在重力除尘器和布袋除尘器之间加入旋风除尘装置,得到的旋风灰可以作为煤粉添加剂。对首秦高炉旋风灰进行粒度和化学成分分析,研究发现高炉旋风灰可以降低煤粉着火温度,提高燃烧效率,且其粒度分布与喷吹煤粉相似,可以作为高炉喷吹煤粉添加剂。通过实验室测定煤粉添加不同比例旋风灰后的燃烧率,确定在富氧率为3%,旋风灰添加比例为6%的条件下,可达到最佳的煤粉燃烧效果。旋风灰作为高炉自产的喷煤添加剂,与煤粉混合喷吹可以为企业减轻固废处理负担,同时带来可观的经济效益和社会效益。     

《混凝土结构》课程教学方法探讨

为了提高<混凝土结构>课程教学质量,本文在分析<混凝土结构>课程特点基础上,提出了改进的教学方法,即合理安排教学内容,结合传统和现代教学手段,重视课程设计和实践教学环节.实践证明,这些改进的教学方法对于充分挖掘学生潜力,激发求知欲望,提高教学质量,促进教学改革具有重要意义.     

洱海富营养化研究

１９９６年９月，洱海蓝藻暴发，水质恶化，湖泊从８月以前的中营养突变为富营养化湖泊。洱海富营养化的主要原因是由于引种太湖银鱼，导致酷渔滥捕，大力发展网箱养鱼、围湖滩养鱼等，导致湖泊生态系统食物链，食物网遭到严重破坏，生物多样性丧失。     

中国自然草地生态系统服务价值

文中参照Constaza等提出的方法,在对草地生态系统服务价格根据其生物量订正的基础上,逐项估计了各类草地生态系统的各项生态系统服务价值,得出全国草地生态系统每年的服务价值为14979×10⁸US＄。其中扰乱管理价值占1607%,水管理和水供应价值占1444%,侵蚀控制和沉积保存价值占908%,废物处理价值占4203%,授粉价值占783%,生物控制价值占72%,食物和原材料生产价值占2226%,娱乐和文化价值占578%,其它如气体管理价值、土壤形成价值和栖息地价值低于5%。受各类草地生物群落分布广度和单位面积生态服务功能强弱的综合影响,各类草地的生态服务价值贡献率有很大差异,其中,沼泽类对草地生态系统总服务价值的贡献率为5234%。温性草原类、热性草丛类、热性灌草丛类、低地草甸类和高寒草甸类对总服务价值的贡献分别在503%～774%之间,其余类型的草地生态服务价值贡献率在5%以下。     

城市生活垃圾填理场及压缩站的环境影响探讨

简述了填埋法处理城市生活垃圾的全过程，分析这一过程中垃圾压缩站和垃圾填埋场的环境影响，并探讨了控制污染的对策措施。     

土场环境灾害的控制技术

 结合环境岩土工程理论,用散体动力学及统计学方法,研究高台阶土场治理滑坡新机制,土场泥石流扼制及底部泄流等新技术,为排土场在稳定条件下增加堆高、开辟用地新来源、根治泥石流、治理表土基底创造了条件,对保护国土资源、保护矿山生态环境、根治因土场失稳而引起的矿山灾害具有重大意义.     

极限定义的新理解

针对“极限”概念提出了一些见解,并从理论上描述和给出了“极限”的精确定义,从该定义出发,更有助正确理解和掌握“极限”的内在含义。     

Multiple effects of nitrate amendment on the transport, transformation and bioavailability of antimony in a paddy soil-rice plant system

Nitrate (NO₃^?) is known to be actively involved in the processes of mineralization and heavy metal transformation; however, it is unclear whether and how it affects the bioavailability of antimony (Sb) in paddy soils and subsequent Sb accumulation in rice. Here, the effects of NO₃^? on Sb transformation in soil-rice system were investigated with pot experiments over the entire growth period. Results demonstrated that NO₃^? reduced Sb accumulation in brown rice by 15.6% compared to that in the control. After amendment with NO₃^?, the Sb content in rice plants increased initially and then gradually decreased (in roots by 46.1%). During the first 15 days, the soil pH increased, the oxidation of Sb(III) and sulfides was promoted, but the reduction of iron oxide minerals was inhibited, resulting in the release of adsorbed and organic-bound Sb from soil. The microbial arsenite-oxidizing marker gene aoxB played an important role in Sb(III) oxidation. From days 15 to 45, after NO₃^? was partially consumed, the soil pH decreased, and the reductive dissolution of Fe(III)-bearing minerals was enhanced; consequently, iron oxide-bound Sb was transformed into adsorbed and dissolved Sb species. After day 45, NO₃^? was completely reduced, Sb(V) was evidently reduced to Sb(III), and green rust was generated gradually. Thus, the available Sb decreased due to its enhanced affinity for iron oxides. Moreover, NO₃^? inhibited the reductive dissolution of iron minerals, which ultimately caused low Sb availability. Therefore, NO₃^? can chemically and biologically reduce the Sb availability in paddy soils and alleviate Sb accumulation in rice. This study provides a potential strategy for decreasing Sb accumulation in rice in the Sb-contaminated sites.     

两株柴油降解菌的性能研究

以0#柴油为惟一碳源,对两株柴油降解菌DS-Ⅰ菌和DS-Ⅲ菌降低液体表面张力的能力、柴油降解动力学及表面活性物质成分进行了研究。实验结果表明:DS-Ⅰ菌和DS-Ⅲ菌在生长过程中均可产生糖脂类生物表面活性物质,使发酵液表面张力降低;在11d的发酵时间内,DS-Ⅰ菌和DS-Ⅲ菌使发酵液中柴油的质量浓度从48.72m g/L分别降至16.64m g/L和9.17m g/L,柴油降解率分别为65.84%和81.18%,柴油降解速率分别为5.16m g/(L.d)和5.96m g/(L.d)。发酵液表面张力的降低与柴油的降解效果有显著的相关性。DS-Ⅲ菌在疏水性、对柴油的生长适应性和柴油降解速率等方面比DS-Ⅰ菌更好。