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121.
Leila G. Rhue Mitchell J. Small 《Journal of the American Water Resources Association》1986,22(1):121-127
ABSTRACT: The application of a low-flow assessment model is illustrated for the Monogahela River Basin. The model simulates the impact of reservoir operating rules and consumptive use limitation policies on low-flow frequency at downstream locations in the basin. Policies are evaluated using an observed flow sequence and synthetic flow inputs. The paper reviews the historical development of flow management on the Monogahela to provide background for the current study. 相似文献
122.
简述了水煤浆加压气化制合成氨系统的特点,着重介绍了该系统制气工段和净化工段的三废排放情况及治理措施,并对仍存在的问题提出了看法。 相似文献
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Raja S Ravikrishna R Kommalapati RR Valsaraj KT 《Environmental monitoring and assessment》2005,110(1-3):99-120
Seventeen fog events were sampled in Baton Rouge, Louisiana during 2002–2004 as part of characterizing wet deposition by fogwater
in the heavily industrialized corridor along the Louisiana Gulf Coast in the United States. These samples were analyzed for
chemical characteristics such as pH, conductivity, total organic and inorganic carbon, total metals and the principal ion
concentrations. The dominant ionic species in all samples were NH4+, NO3−, Cl− and SO42−. The pH of the fogwater sampled had a mean value of 6.7 with two cases of acidic pH of 4.7. Rainwater and fogwater pH were
similar in this region. The acidity of fogwater was a result of NO3− but partly offset by high NH4+. The measured gaseous SO2 accounted for a small percentage of the observed sulfate concentration, indicating additional gas-to-particle conversion
of SO2 to sulfate in fogwater. The gaseous NOx accounted for most of the dissolved nitrate and nitrite concentration in fogwater. The high chloride concentration was attributable
to the degradation of chlorinated organics in the atmosphere. The metal composition was traced directly to soil-derived aerosol
precursors in the air. The major metals observed in fogwater were Na, K, Ca, Fe, Al, Mg and Zn. Of these Na, K, Ca and Mg
were predominant with mean concentrations > 100 μM. Al, Fe and Zn were present in the samples, at mean concentrations < 100
μM. Small concentrations of Mn (7.8 μM), Cu (2 μM), Pb (0.07 μM) and As (0.32 μM) were also observed in the fogwaters, and
these were shown to result from particulates (PM2.5) in the atmosphere. The contribution to both ions and metals from the marine sources in the Louisiana Gulf Coast was minimal.
The concentrations of all principal ionic species and metals in fogwater were 1–2 orders of magnitude larger than in rainwater.
Several linear alkane organic compounds were observed in the fogwater, representing the contributions from petroleum products
at concentrations far exceeding their aqueous solubility. A pesticide (atrazine) was also observed in fogwater, representing
the contribution from the agricultural activities nearby. 相似文献
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128.
Monitoring of Pesticide Residues in Fruits 总被引:1,自引:0,他引:1
Fruit samples of ber, grapes and guava analysed for pesticide residues employing multiresidue analysis by gas liquid chromatography equipped with ECD and NPD detectors and capillary columns showed contamination with organochlorine, synthetic pyrethroid and organophosphate insecticides. Among organochlorines, HCH, DDT and endosulfan were detected in almost all the samples. Residues of HCH and DDT were maximum in ber followed by grapes and guava where as of endosulfan were maximum in guava followed by grapes and ber. All the fruit samples showed the presence of residues with one or the other group of pesticides. Residues of none of the pesticides exceeded the MRL values in any sample. On the basis of these studies, it is suggested that monitoring studies should be extended to other fruits grown in different agro climatic regions which may serve as basis for future policy in chemical use. 相似文献
129.
采用无需衍生化的同相萃取为前处理手段,高效液相色谱-串联四极杆质谱联用技术(LCMSMS)为检测手段,在电喷雾电离正离子模式下,对澳大利亚畜牧业污水中常见的大环内酯和拟除虫菊酯两类共7种驱虫剂物质的残留,建立了一次进样下的有效快速分析方法.经一系列优化试验,确定了以50%丙酮+50%乙腈为洗提剂、每次4 mL共8 mL的洗提方法.结果表明,该固相萃取技术(SPE)的加标回收试验结果较好,各化合物的平均回收率为95.50%~108.00%,相对标准差范围为0.73%-8.82%.以含10mmoL/L醋酸铵、0.1%甲酸的超纯水和甲醇混合溶液为流动相,以准分子离子峰[M+NH_4]~+、[M+H]~+作为母离子的定量离子对,所建立的1~500 ng/mL范围内的8点校正曲线中.各物质的相关系数均高于0.998 0,定量限范围为0.03-2.47 ng/mL.实际样品测定时.不同处理流程中各化合物的残留浓度有较好地体现. 相似文献
130.
城市工业化灾害及其综合减灾设计对策──兼论北京城市防灾减灾的规划编研思路 总被引:1,自引:0,他引:1
金磊 《城市环境与城市生态》2000,(4)
文章从城市减灾问题研究的实际出发 ,认为城市灾害系统中对于城市威胁最大的城市工业化灾害至今重视不够 ,甚至缺少必要评估。无论是大中城市发展 ,还是大力倡导的中国小城镇建设 ,城市工业化防灾应引起关注。因此提出不仅应研究城市减灾中的工业化致灾问题 ,还必须关注工业建筑及建设中的防灾规划及布局 ,这是一项极为重要的可持续发展战略。 相似文献