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971.
Complex toxic effects of Cd2+, Zn2+, and acid rain on growth of kidney bean (Phaseolus vulgaris L) were studied in a pot experiment by measurement of fresh weights of the plants, determination of surperoxide dismutase (SOD), peroxidase (POD), and lipid peroxidation (MDA) in the plant organs, and observation of injury symptoms. The experimental results demonstrated that all treatments of Cd2+, Zn2+, and/or acid rain significantly decreased fresh weights of kidney bean and caused toxic effects on growth of the plants, especially higher amounts of Cd2+ and Zn2+ and higher acidity of acid rain. Combination of these three pollutant factors resulted in more serious toxic effects than any single pollutant and than combinations of any two pollutants. SOD, POD, and MDA in the plant organs changed with different pollution levels, but MDA content in the leaves showed the best relationship between the pollution levels and toxic effects.  相似文献   
972.
环境可接受的甲酸盐钻井完井液性能探讨   总被引:1,自引:0,他引:1  
随着环境保护的要求日益严格,一种新型的钻井完井液 ── 环境可接受的甲酸盐钻井完井液,正在国外现场试验和推广应用,目前已引起国内有关研究人员和技术人员的高度重视。分析了甲酸盐钻井完井液的工艺性能,并着重对甲酸盐钻井完井液在环境保护方面的优越性能进行了探讨。  相似文献   
973.
The combined effect of ultraviolet (UV)-ozonation (O3) of aqueous 14C-TNT solutions followed by direct addition of the solutions to aerobic soils was examined as a method of disposal. The effect of TNT concentration was studied on both UV-O3 and soil metabolism. The amount of TNT degraded by either process decreased as the concentration increased. UV-O3 of a 1 ppm solution of TNT using a laboratory 450 W lamp for 10, 20, and 30 minutes resulted in substantial fragmentation of the ring and an increase in polarity of the resultant products. Soil metabolism, as measured by metabolic CO2 evolution, increased as the time of prior UV-O3 increased. A large amount of the 14C associated with 14C-TNT recovered from soil was in the non-extractable fraction. When a , adapted to metabolize -nitrophenol or picric acid as a sole source of carbon and nitrogen, was substituted for the soil phase, about 25% of the added 14C appeared as 14CO2. 1,3,5-Trinitrobenzene, 2,4,6-trinitrobenzaldehyde, 3,5-dinitrophenol, 3, 5-dinitrocatechol, 3,5-dinitrohydroquinone, and oxalic acid were identified as products of UV-O3. Rapid destruction of TNT took place in a large 66 lamp unit, and the resultant distribution of 14C was similar to the results from the laboratory studies.  相似文献   
974.
利用人工降雨手段化汛期特大暴雨灾害为可利用水资源   总被引:1,自引:0,他引:1  
利用美国1979-1995年NCEP/NCAR再分析及其它格点资料进行分析。发现汛期影响我国特大暴雨及洪涝灾害的,是一支存在于南,北两半球之间的非亚支“宏观气流系统”,它的气流运行具有一定的规律性,因而,对我国的特大暴雨和洪涝灾害,不但可以进行及时的监测和预报,而且可以在这支宏观气流系统的上游地带施行人工影响云雨工程,把空中丰沛水分降到需要雨水的地区,化洪涝灾害为宝贵的水资源。  相似文献   
975.
曾平  姚廷伸 《四川环境》1991,10(4):12-15
本文系统地综述了自1975年以来分光光度法、催化法、电极溶出伏安法、冷原子吸收和荧光法以及其它方法分析痕量汞的发展状况,并对稀浓度汞标液的保存方法作了介绍。  相似文献   
976.
曾刚  孔翔 《灾害学》1999,14(4):22-26
1998 年长江中下游地区发生的特大洪水具有洪水水位高、洪量大、历时长的特点, 这次洪水灾害造成的直接经济损失超过了2 000 亿元。本文在长江上中游地区降水量总量及强度超常、长江上中下游洪水遭遇严重、分洪区没能发挥作用等洪灾形成主要原因进行分析的基础上, 提出了加大对影响长江流域灾变性气候的研究、调整江湖水系结构、加强区域间防洪的协调和协作等对策建议。  相似文献   
977.
建筑物的雷害损失每年都在发生,而建筑物防雷装置的施工质量存在诸多违反《规范》的问题,应引起设计、施工、质检、监理、用户等单位的重视,以期达到建筑物的安全防雷。  相似文献   
978.
Sediment core samples collected from Lake Chaohu were analyzed for 15 priority polycyclic aromatic hydrocarbons(PAHs)to assess the spatial and temporal distributions of the PAHs during lacustrine sedimentary processes and regional economic development.Assessing the PAH sedimentary records over an approximately 100-year time span,we identified two stages in the PAH inputs and sources(before the 1970 s and after the 1970s)in the eastern lake region near a village,whereas three stages(before the 1950 s,1950s–1990s and after the1990s)were identified in the western lake region near urban and industrial areas.Rapid increases in the PAH depositional fluxes occurred during the second stage due to increased human activities in the Lake Chaohu basin.The composition and isomeric ratios of the PAHs revealed that pyrolysis is the main source of PAHs in this lake.Strong positive relationships between PAH concentration and the total organic carbon concentration,sediment grain size( 4 μm),as well as the local population and Gross Domestic Product indicated that the sedimentary conditions impact the depositional characteristics of the PAHs;simultaneously,socioeconomic activities,such as energy consumption and the levels of urban industrialization and civilization,affect both the composition and abundance of the PAHs.  相似文献   
979.
随着中国经济高速发展以及工业化进程的不断加快,环境污染事故呈频发态势,环境公益诉讼制度实施和公众环保意识不断觉醒,环境司法诉讼案件数量也呈爆发性增长.环境污染损害鉴定评估工作是环境损害赔偿量化的重要基础性工作,科学的评价环境损害问题已成为环境管理研究的重要课题.基于对环境损害评估制度的调研,介绍了国内外研究现状进展,分析了黑龙江省工作现状,探讨了当前存在的问题,提出了相应的对策建议,为进一步推进环境损害鉴定评估工作发展和完善提供参考.  相似文献   
980.
Phase change materials (PCMs) that can store and release heat energy over the temperature range from 363 to 393 K are crucial for solar absorption cooling, and it is worthy to seek new solid-liquid PCMs candidates that melt and crystallize in this temperature range. In this paper, (E)-3-m-tolylbut-2-enoic acid (mTBEA) was applied as a PCM candidate. Its thermal energy storage properties and thermal stability were systematically investigated. The results showed that mTBEA melted at 382.9 ± 0.5 K and crystallized at about 364 K, with a melting enthalpy (ΔfusH) of 138.4 ± 6.9 J g?1 and showed good long-term cyclic stability and thermal stability. The supercooling of mTBEA was stabilized at about 20 K, indicating that the conservation condition of melted mTBEA could be simple. In addition, the melted mTBEA could release all the absorbed thermal energy upon crystallizing. Besides, mTBEA exhibited good thermal stability for it to be applied as PCM. Hence, mTBEA is a promising PCM candidate for solar absorption cooling. Furthermore, the heat capacity of mTBEA was measured by modulated temperature differential scanning calorimetry (MTDSC) over the temperature range from 198.15 to 431.15 K, and the molar thermodynamic functions, [HT-H298.15]m and [ST-S298.15]m, were calculated based on the fitted molar heat capacity data.  相似文献   
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