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241.
以半知菌属疣孢漆斑菌Myrothecium verrucaria NF-08为供试菌,采用响应面方法优化菌株产漆酶条件,并以其漆酶粗酶进行3种结构类型6种染料的脱色试验,考察了粗酶浓度、温度和p H值对脱色率的影响.两水平析因设计、中心组合设计和验证试验结果表明:葡萄糖浓度为15.4 g·L~(-1)、蛋白胨浓度为43.3 g·L~(-1)和培养基初始p H值为6.68时,漆酶活性达到最大值(25.58±1.60)U·m L~(-1),是单因素试验(16.82 U·m L~(-1))的1.52倍,提高了52.1%.以上述发酵条件获得的M.verrucaria NF-08漆酶粗酶对3种结构类型染料均有脱色效果,排序为偶氮类优于芳甲烷类优于蒽醌类.脱色率随粗酶浓度增大(2~8 U·m L~(-1))、反应温度升高(15~35℃)而上升,随p H值上升(4~10)而下降.粗酶浓度为5 U·m L~(-1),反应温度为25℃,p H值为4时,偶氮类染料铬黑T和芳甲烷类染料碱性品红即可几乎完全脱色,脱色率分别为99.2%和94.6%. 相似文献
242.
243.
利用AA3流动注射分析仪,同时对地表水中的挥发酚和氰化物进行测定,分析流程中使用了在线恒温蒸馏器。同传统的分析方法相比,本法分析测定数据准确、可靠、高效,大大缩短了测定时间,只需将两种标准配制成混合标样,一次取样完成两个项目的测定。回收率为90%~110%,相关系数达到0.9992以上。 相似文献
244.
HUANG Zhi ZHOU Wen YU Ya-juan ZHANG Ai-qian HAN Shuo-kui WANG Lian-sheng 《环境科学学报(英文版)》2004,16(1):56-60
Enrichment of volatile organic compounds(VOC) and semi-volatility organic compounds(SVOC) in surface microlayer(SM) of three ddnking water sources were studied. The enrichment factor(EFs) were 0.67 to 13.37 and 0.16 to 136, respectively. The results showed some VOC and most SVOC could enrich in SM. Some EFs of SVOC was quite high. Suspension and temperature could affect EFs of SVOC, slim wind and water movement do not destroy enrichment of organic in SM. 相似文献
245.
任于翎 《辽宁城乡环境科技》2004,24(5):41-43,46
通过对顺城河北地区地表水环境现状特点及其污染状况的调查详细分析了各支流的纳污量,了解河北地区各支流对浑河主河道的“污染贡献”,运用科学的方法确定各功能水质目标,提出水污染总量、控制削减方案和治理方案。 相似文献
246.
Determination of polyfluoroalkyl compounds in water and suspended particulate matter in the river Elbe and North Sea, Germany 总被引:1,自引:0,他引:1
Lutz Ahrens Merle Plassmann Zhiyong Xie Ralf Ebinghaus 《Frontiers of Environmental Science & Engineering in China》2009,3(2):152-170
The distribution of polyfluoroalkyl compounds (PFCs) in the dissolved and particulate phase and their discharge from the river
Elbe into the North Sea were studied. The PFCs quantified included C4-C8 perfluorinated sulfonates (PFSAs), 6:2 fluorotelomer sulfonate (6:2 FTS), C6 and C8 perfluorinated sulfinates (PFSiAs), C4-C12 perfluorinated carboxylic acids (PFCAs), perfluoro-3,7-dimethyl-octanoic acid (3,7m2-PFOA), perfluorooctane sulfonamide (FOSA), and n-ethyl perfluroctane sulfonamidoethanol (EtFOSE). PFCs were mostly distributed
in the dissolved phase, where perfluorooctanoic acid (PFOA) dominated with 2.9–12.5 ng/L. In the suspended particulate matter
FOSA and perfluorooctane sulfonate (PFOS) showed the highest concentrations (4.0 ng/L and 2.3 ng/L, respectively). The total
flux of ΣPFCs from the river Elbe was estimated to be 802 kg/year for the dissolved phase and 152 kg/year for the particulate
phase. This indicates that the river Elbe acts as a source of PFCs into the North Sea. However, the concentrations of perfluorobutane
sulfonate (PFBS) and perfluorobutanoic acid (PFBA) in the North Sea were higher than that in the river Elbe, thus an alternative
source must exist for these compounds. 相似文献
247.
Constructed wetland (CW) is the preferred means of controlling water quality because of its natural treatment mechanisms and
function as a secondary or tertiary treatment unit. CW is increasingly applied in Korea for secondary e uent of livestock wastewater
treatment. This study was conducted to recognize the characteristics of contaminants in the accumulated sediment at the bottom soil
layer and to reduce the phosphorus release from sediments of the free water surface CW for the treatment of secondary piggery
wastewater e uent from a livestock wastewater treatment facility. The results revealed that the dominant phosphorus existence types
at near the inlet of the CW were non-apatite phosphorus (59%) and residual phosphorus (32%) suggesting that most of the particles of
the influent are made up of inorganic materials and dead cells. Sediment accumulation is important when determining the long-term
maintenance requirements over the lifetime of CW. Continuous monitoring will be performed for a further assessment of the CW
system and design. 相似文献
248.
249.
Accumulation of copper (Cu) and cadmium (Cd) in six rice cultivars (94D-22, 94D-54, 94D-64, Gui630, YY-1 and KY1360) was evaluated through exposure to heavy metal contamination (100 mg/kg Cu, 1.0 mg/kg Cd, and 100 mg/kg Cu + 1.0 mg/kg Cd) in a greenhouse. The dry weight of shoot and root, concentrations of Cu and Cd in plant tissues and the Cu, Cd, P, Fe concentrations in the root surface iron plaques were analyzed eight weeks later after treatment. The results indicated that the plant biomass was mainly determined by rice genotypes, not Cu and Cd content in soil. Separated treatment with Cu/Cd increased each metal level in shoot, root and iron plaques. Soil Cu enhanced Cd accumulation in tissues. In contrast, Cu concentrations in shoot and root was unaffected by soil Cd. Compared to single metal contamination, combined treatment increased Cd content by 110.6%, 77.0% and 45.2% in shoot, and by 112.7%, 51.2% and 18.4% in root for Gui630, YY-1 and KY1360, respectively. The content level of Cu or Cd in root surface iron plaques was not affected by their soil content. Cu promoted Fe accumulation in iron plaques, while Cd has no effect on P and Fe accumulation in it. The translocation of Cu and Cd from iron plaques to root and shoot was also discussed. These results might be beneficial in selecting cultivars with low heavy metal accumulation and designing strategies for soil bioremediation. 相似文献
250.
始于2004年的海南岛多目标生态地球化学调查,对全岛的地表水进行了区域调查取样,分析测试了24项指标(部分样品增加测试12项)。测试结果表明,大多数指标优于国家地表水环境质量标准(GB3838-2002)中III类水体水质标准,只有Hg和总氮存在区域性的超Ⅲ类水体水质。经对样品的聚类分析研究表明,全岛地表水样品主要分为4类,分别反映了地表植被、海水入侵、灌溉水田排水、矿山废水排放对地表水化学成分的控制作用。在此认识的基础上,依地表水样品所处的土地利用方式的不同,按一定顺序对样品进行编号赋值(沿海的土地视为"海洋利用方式"),该赋值与聚类分析所得到的样品类别值之间存在极显著的正相关性,相关系数达0.8280,表明海南岛的土地利用方式是控制地表水地球化学特征的关键因素,从而为海南岛地表水环境质量的保护和提高指出了方向。 相似文献