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801.
凤眼莲净化含酚污水的研究——Ⅰ.盆栽和氧化塘试验及几种环境条件对除酚的影响 总被引:10,自引:0,他引:10
通过盆栽、模拟箱和氧化塘中凤眼莲净化含酚污水的试验表明:放养凤眼莲能使除酚过程加快,在0.6—10mg/L酚浓度范围内,植物净化速率为一般自然净化速率的2—3倍。在温度17—37℃范围内,凤眼莲均能明显加速酚水的净化。光照强度对凤眼莲净化酚水速率无显著影响。平衡地提高水中矿质营养元素的浓度,能加速除酚的过程。 水中含酚量小于1mg/L不造成植株中酚的残留;6mg/L以下酚含量增加亦不明显;10mg/L以上则随酚浓度的提高,植株中酚含量成倍增加。 相似文献
802.
适当的仪器质量分馏校正是提高同位素分析数据精度的关键 ,重新“复活”了的铅同位素“双稀释剂”测定方法可实现严格的仪器质量分馏校正。以区域锆石U -Pb年龄为控制点的“AGSO -CSIRO”铅同位素模式年龄方法可获得精度很高的定年结果 ,铅同位素研究的应用必将因此而得到更大的发展。 相似文献
803.
CHANG Qing 《环境科学学报(英文版)》2001,13(1):104-107
IntroductionApreparationmethodofpolyferricsulfate (PFS)coagulantwasreportedbyJapanesescientists(Yang ,1986)intheseventies.SincetheeightiesthepreparationandapplicationofPFShavebeenwidelyinvestigatedinChinabecauseofitshighcoagulationefficiencyinwatertreatmen… 相似文献
804.
K. C. Chun R. W. Chang G. P. Williams Y. S. Chang D. Tomasko K. LaGory J. Ditmars H. D. Chun B. -K. Lee 《Environmental Engineering and Policy》1999,2(3):131-143
A framework for evaluating alternative management strategies for the Nakdong River Basin in the Republic of Korea (South Korea) was developed and applied jointly by Argonne National Laboratory in Argonne, Illinois, USA, and the Research Institute of Industrial Science and Technology in Pohang, South Korea. Water from this basin, the second largest in South Korea, supports a total population of more than 13 million people. Rapid industrial expansion, urbanization, and population growth have dramatically increased the demand for water and have severely degraded water quality, particularly near large industrial complexes and in the lower portion of the basin. Management strategies for the entire basin through to the year {dy2011} were evaluated with a computer model for basin-wide predictions of water flow and quality (HSPF). This continuous-event model was developed and calibrated using site-specific data for the basin over a two-year period (1994-1995) that included periods of both high (monsoonal) and low (drought) flows. Water quality impacts for different wastewater treatment strategies were assessed in terms of biochemical oxygen demand (BOD), nitrogen (N) and phosphorous (P) levels. The results of the study indicate that BOD levels in the main stem of the Nakdong River below the Kumhogang (a major tributary with low flow and heavy pollution loads) cannot be significantly improved by reducing direct BOD loads from point sources along the river. To reduce main stem BOD levels, the nutrient loading to the river must be reduced. In order to reduce these loads, additional advanced treatment methods (i.e., tertiary treatment) must be incorporated in the treatment facilities to remove N and P. The discharge inventory data further suggest that a large portion of N and P loads are derived from non-point agricultural practices. Reduction of these loads is difficult to accomplish and may require extensive modifications in agricultural and land-use practices. The modeling frame-work developed provides a means to evaluate these and other basin management strategies. 相似文献
805.
806.
与污水非集中处理相比,污水集中处理区域建设项目的水环境影响出现一些新特点。从污水集中处理区域建设项目应否接受保护行政主管部门的监管、污水集中处理区域建设项目水环境保护的分类管理标准、污水集中处理区域建设项目水环境影响评价的内容三个方面进行探讨。 相似文献
807.
植物对二氧化硫的反应和抗性研究 Ⅸ.SO2伤害与叶组织电阻的变化 总被引:2,自引:0,他引:2
应用祝宗岭等(1982)改进的在稳流下测量植物组织电阻的中段电压降法,测定了小麦叶片在SO_2或HSO_3-引起伤害过程中的叶组织电阻变化,并与离子外渗的变化进行了比较。小麦接触不同浓度SO_2,如浓度在伤害阈值以下,组织电阻无明显变化.如以引起伤害的浓度处理,在出现伤害的初始症状前组织电阻就开始下降,而随着熏气时间的延长在出现初始症状时则有一急剧下降。浓度高,电阻下降也大。平行测定离子外渗的变化,它与组织电阻呈负相关,相关系数为0.936,回归方程为y=412.7-28.3x。 用不同浓度的HSO_3~-处理小麦离体叶,组织电阻也随浓度的增加而下降。 试验结果说明,测定叶组织的电阻可以比较灵敏地反映叶细胞质膜的结构和功能受损的程度。这方法可应用于原位叶或离体叶测定,也便于作动态观测。 相似文献
808.
Determnation of ochratoxin A in grain by monoclonal antibody-based enzyme-linked immunosorbent assay
Yang Chuanhe Luo Xueyun Liu Chang Li Wenyan Li Yiepeng Zhao Danyu Ji Rong 《环境科学学报(英文版)》1994,6(1):116-122
DetermnationofochratoxinAingrainbymonoclonalantibody-basedenzyme-linkedimmunosorbentassayYangChuanhe;LuoXueyun;LiuChang;LiWen... 相似文献
809.
废塑料生产汽油,柴油最佳生产工艺及设备 总被引:2,自引:0,他引:2
针对目前用废塑料生产汽油、柴油工艺及设备中存在缺点,研制开发出一套新工艺和设备。采用两段熔化两段催化工艺,原料不必分选,利用自制高效催化剂生产出符合国家标准的汽油、柴油。 相似文献
810.
Xiying Hao Chi Chang H. Henry Janzen Brett R. Hill Troy Ormann 《Agriculture, ecosystems & environment》2005,110(3-4):185-194
Elevated atmospheric NH3 levels near intensive livestock operations can add significant N to local agroecosystems. In this study, the potential atmospheric NH3 sorbed by soil and water was assessed over a 2-year period starting October 2000 in an intensive livestock production area in southern Alberta, Canada. Fifty-two uneven grid sampling sites were selected in the 53,905 ha study area. The sorption rate of atmospheric NH3 was estimated weekly by exposing distilled water and air-dried soil samples to the atmosphere at the sampling sites. The increases in NH4–N content in the samples after 1-week exposure was regarded as an index of the atmospheric NH3 sorbed for that week. The NH3 sorption rates were highly variable across the 52 sites, with water ranging from 4 to 125 kg ha−1 year−1 with a mean of 22 kg N ha−1 year−1 and soil from 5 to 84 kg N ha−1 year−1 with a mean of 20 kg N ha−1 year−1. Considerable variation in NH3–N sorption across the study area reflects the effects of size, direction (upwind or downwind) and proximity of nearby livestock operations or other NH3 sources and operators’ activities around the sampling sites. The NH3 sorption rate at each site also varied considerably in response to weather conditions. The high rate of NH3 input poses a direct risk of surface water eutrophication in intensive livestock operation areas. If fertilizer recommendations are not reduced to account for NH3 sorption by soil, excess N may also contribute to eutrophication through runoff and leaching. 相似文献