甲醇燃料车尾气净化催化剂的研究(Ⅰ)──单组分催化剂对甲醇的深度氧化

利用色谱－微反联用技术对甲醇深度氧化进行了研究。结果表明：甲醇在所有催化剂上氧化时均产生副产物甲醛及甲酸甲酯;非贵金属氧化物催化剂以Ｃｕ－Ｏ／ｒ－Ａｌ２Ｏ３的活性最优,其最佳负载量为１０％－２０％,不同的制备方法中以均匀沉淀法制备的催化剂最好;贵金属催化剂中Ａｇ／ｒ－Ａｌ２Ｏ３的活性较好,其甲醇氧化的Ｔ５０,Ｔ９５分别只有１３５℃和１９０℃,而且伴生的甲醛及甲酸甲酯浓度也较低。不同催化剂的活性与其     

数字式光学测尘仪对不同呼吸性粉尘浓度转换系数的求取

本文论述了用BY-1型呼吸性粉尘标定采样器,在云南锡业公司矿山和冶炼厂现场测定、求取P-5L_2型和TM型光学测尘仪的读数与呼吸性粉尘(空气动力学直径:<7.07μm和<10μm)质量浓度转换系数(K)的方法和结果.研究表明,由深色矿物组成的粉尘,其K值大于由浅色矿物组成的粉尘的K值.P-5L_2型光学测尘仪间的测尘误差85％以上在±10％以内,平均为±6.68％.     

Habitat-quality effects on metapopulation dynamics in greater white-toothed shrews, Crocidura russula

The effects of patch size and isolation on metapopulation dynamics have received wide empirical support and theoretical formalization. By contrast, the effects of patch quality seem largely underinvestigated, partly due to technical difficulties in properly assessing quality. Here we combine habitat-quality modeling with four years of demographic monitoring in a metapopulation of greater white-toothed shrews (Crocidura russula) to investigate the role of patch quality on metapopulation processes. Together, local patch quality and connectivity significantly enhanced local population sizes and occupancy rates (R2 = 14% and 19%, respectively). Accounting for the quality of patches connected to the focal one and acting as potential sources improved slightly the model explanatory power for local population sizes, pointing to significant source-sink dynamics. Local habitat quality, in interaction with connectivity, also increased colonization rate (R2 = 28%), suggesting the ability of immigrants to target high-quality patches. Overall, patterns were best explained when assuming a mean dispersal distance of 800 m, a realistic value for the species under study. Our results thus provide evidence that patch quality, in interaction with connectivity, may affect major demographic processes.     

Habitat type determines herbivory controls over CO2 fluxes in a warmer Arctic

High-latitude ecosystems store large amounts of carbon (C); however, the C storage of these ecosystems is under threat from both climate warming and increased levels of herbivory. In this study we examined the combined role of herbivores and climate warming as drivers of CO2 fluxes in two typical high-latitude habitats (mesic heath and wet meadow). We hypothesized that both herbivory and climate warming would reduce the C sink strength of Arctic tundra through their combined effects on plant biomass and gross ecosystem photosynthesis and on decomposition rates and the abiotic environment. To test this hypothesis we employed experimental warming (via International Tundra Experiment [ITEX] chambers) and grazing (via captive Barnacle Geese) in a three-year factorial field experiment. Ecosystem CO2 fluxes (net ecosystem exchange of CO2, ecosystem respiration, and gross ecosystem photosynthesis) were measured in all treatments at varying intensity over the three growing seasons to capture the impact of the treatments on a range of temporal scales (diurnal, seasonal, and interannual). Grazing and warming treatments had markedly different effects on CO2 fluxes in the two tundra habitats. Grazing caused a strong reduction in CO2 assimilation in the wet meadow, while warming reduced CO2 efflux from the mesic heath. Treatment effects on net ecosystem exchange largely derived from the modification of gross ecosystem photosynthesis rather than ecosystem respiration. In this study we have demonstrated that on the habitat scale, grazing by geese is a strong driver of net ecosystem exchange of CO2, with the potential to reduce the CO2 sink strength of Arctic ecosystems. Our results highlight that the large reduction in plant biomass due to goose grazing in the Arctic noted in several studies can alter the C balance of wet tundra ecosystems. We conclude that herbivory will modulate direct climate warming responses of Arctic tundra with implications for the ecosystem C balance; however, the magnitude and direction of the response will be habitat-specific.     

Ochrobactrum anthropi 对苯胺的降解特性

利用自行筛选驯经的苯胺降解菌人苍白杆菌对影响胺降解的各种主要因素进行了研究。发现降解菌在３５℃,ＰＨ．下及苯胺初始浓度２００－８００ｍｇ／Ｌ的范围内保持高活必在最大降解速率率达到１０．０５ｍｇ．（Ｌ．ｈ）＾－１。     

CTMAB-膨润土去除水中有机物的性能及机理

用溴化十六烷基三甲铵（CTMAB）改性膨润土,研究了CTMAB膨润土去除水中苯、甲苯、乙苯、硝基苯、苯胺、苯酚、对硝基苯酚的性能、机理及影响因素。结果表明,CTMAB-膨润土去除水中有机物的能力远大于原土;CTMAB-膨润土对苯、甲苯、乙苯的等温吸附曲线呈线性;对水中苯酚、对硝基苯酚的等温吸附曲线呈非线性;对苯胺、硝基苯的等温吸附曲线基本呈线性。CTMAB-膨润土吸附水中有机物的性能及机理与有机物的水溶性或辛醇－水分配系数有关。     

天津地区土壤多环芳烃在剖面中的纵向分布特征

在天津市北部山区、中部农田和东南部油田采油作业区分别采集了土壤样品 ,研究了土壤中多环芳烃 (PAHs)的纵向分布特征 ,并对土壤中多环芳烃的来源进行了分析 .结果表明 ,PAHs含量峰值一般位于土壤表层或次表层 ,并随着土壤剖面的加深而减少 .农田菜地土壤PAHs在 4 0cm深处含量仍然较高 ,而油田仅表层 3cm富集PAHs ,这与耕作土壤表层常受到人为扰动有关 .与高环物质相比 ,低环物质更容易向下迁移 .土壤中有机碳的含量、土壤的性质以及土壤的粒度均是影响PAHs迁移的重要因素 .山区和菜地土壤中PAHs主要来自燃烧源 ,而油田则显示为石油源和燃烧源的混合源 .     

高、中频混响声场噪声治理技术的研究及应用

我国目前纺织厂织造车间的噪声级均较高。应用吸声降噪原理 ,通过模拟、中试和二项试点三步的实践证明 ,采用在厂房建筑上架设大面积“强吸声吊顶”技术的方法 ,能使织造车间的噪声降低 4～ 6dB(A) ,收到较好的降噪效果。     

电子束氨法烟气脱硫技术工艺研究

介绍了位于四川省绵阳市科学城热电厂的电子束氨法烟气脱硫脱硝工业试验装置和在该装置上进行的较全面的工艺研究 ,确定了影响SO2 脱除效率的主要参数 ,为北京京丰热电EA FGD工业示范工程设计提供了重要依据     

海上溢油下潜过程特征的实验考察

海上溢油行为的研究是预测其归宿、控制其危害的关键所在。由于目前对溢油下潜于水时所受多因素影响、经历多个子过程的综合效应不清,文章用挡板烧瓶模拟波浪,考察其行为特征。结果表明:波浪类型对下潜率影响最大,破碎波和规则波下油的下潜率差异可达79.8%;上浮过程的影响可使得下潜率随时间出现最大值,随分散剂含量的增加有最大值。对比静置中下潜率的变化规律,可认为波浪通过夹带和破碎作用使油下潜,分散剂则增加了下潜稳定性。实验结果可对海面溢油下潜过程的预测提供理论依据和实验数据。