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This is the first study of the flocculation of dissolved Fe, Al, Mn, Si, Cu, Pb and Zn during mixing in Zhujiang Estuary, based on the experiment on a series of solutions of salinities ranging from 0 to 24 by mixing the Zhujiang water near Zhongshan University and the seawater in Wan-shan Archipelago area. The mechanism of flocculation of the 7 elements is explored, and the effects of time, acidity and temperature on flocculation are discussed. The results show that the flocculation rates of Fe and Pb in the Zhujiang water are almost a hundred per cent, while that forCu reaches 76%; for Mn, 51%; for Al, 48%; for Zn, 28%; and for Si, 1.2%, indicating that Si is conservative. 相似文献
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系统应用电子技术、计算机技术、无线电通讯技术于水文测报;是水文数据采集、模块现场存储与无线电遥测相结合的,集水文资料采集、电讯整编和水文自动测报于一体的综合性系统。 相似文献
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南海表层水中的溶解态Cu,Pb, Zn,Cd 总被引:9,自引:0,他引:9
于1998年“南海海洋环境调查”外业工作期间在南海的各个站位,按照严格的防沾污措施采集了106个表层海水样品.采用溶剂萃取-石墨炉原子吸收法对样品中的痕量重金属Cu,Pb,Zn,Cd含量进行了分析测试.测得各重金属的平均值如下:Cu 0.100 μg/dm3,Pb 0.060μg/dm3,Zn 0.086 μg/dm3,Cd 0.007μg/dm3,接近世界大洋水的浓度水平.各重金属的空间分布呈现出海区周边含量高于中央,浓度有自近岸向远海逐渐减小的趋势.相关分析的结果表明各重金属夏季相关性优于冬季,Cu与Cd存在良好的正相关关系,并且首次在南海表层水发现Cu,Cd与营养盐的相关关系.将重金属浓度值作数理统计分析,得到它们在南海的基线值. 相似文献
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Hg,Cu,Cd,Zn 对真鲷仔鱼的急性毒性研究 总被引:5,自引:1,他引:5
本文采用静水生物试验法测定了Hg,Cu,Cd,Zn对真鲷仔鱼(2周龄)的急性毒性。结果表明:Hg,Cu,Cd,Zn对真鲷仔鱼24h的LC_(50)分别为0.025,0.31,5.00和3.70 mg/L,48h的LC_(50)分别为0.016,0.24,1.72和2.22mg/L,72h的LC_(50)分别为0.006,0.11,O.56和0.92mg/L,96h的LC_(50)分别为O.004,0.07,0.27和0.44 mg/L。Hg,Cu对真鲷仔鱼的影响极为显著,Zn,Cd的影响虽然很大,但比Hg,Cu低得多。Cd的毒性比Zn强,但毒理作用较为缓慢。4种重金属的毒性顺序为Hg>Cu>Cd>Zn。 相似文献
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John M. Quinn A. Bryce Cooper Robert J. Davies‐Colley J. Christopher Rutherford R. Bruce Williamson 《新西兰海洋与淡水研究杂志》2013,47(5):579-597
Water quality, habitat, and biota were compared during spring amongst c. 100 m reaches on 11 streams draining pasture, native (podocarp‐broadleaf) forest, and exotic pine forest established on pasture 15 years previously. Differences were greatest between the pasture and native forest streams. Only 1–3% of incident light reached native and pine forest streams whereas 30% reached pasture streams. Pasture streams had 2.2°C higher mean temperature than the native streams, and 5‐fold higher nitrate, 30‐fold higher algal biomass, and 11‐fold higher gross photosynthesis. Native streams were 60% wider than pasture, with pine streams intermediate. Pine and pasture streams had 3‐fold higher suspended solids and fine sediment stored in the streambed than native streams. Woody debris volume was 17‐fold greater in pine than pasture streams, with native streams intermediate. Invertebrate taxa richness did not differ between land uses. Community composition differed most between pasture and native forest, with pine forest streams intermediate. Invertebrate densities were 3‐fold higher in pasture than native streams, mainly because of more chironomids and snails, but mayflies, stoneflies, and caddisflies densities were 2–3‐fold higher in forest streams than pasture. 相似文献
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欧,美,日的人造海滩 总被引:4,自引:0,他引:4
众所周知,青岛沙滩与北戴河沙滩是我国著名的旅游胜地,这是由于天然形成的沙滩吸引着众多的游客去避署和游泳,欣赏大自然的风光。 我国大陆海岸线长18000多公里,沙砾质海岸并不太多。沙砾主要来自河流、海岸和海岛的侵蚀,波浪作用常引起沿岸漂沙,加上河 相似文献
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本文参照Tessier推荐的方法,采用顺序提取法测定了长江口内外悬浮体中Pb、Mn、Cd、Fe元素五种化学形态的含量,并研究了盐度从接近零到33之间各重金属元素形态的分布和变化。 相似文献
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图们江口水中Zn,Cd,Pb,Cu的形式分析 总被引:1,自引:0,他引:1
本文用防吸附物理涂汞电极反问极谱对图们江口、东海及日本海水中Zn,Cd,Pb,Cu进行了形式分析,其不稳定态的平均浓度分别为5.9,0.071,0.039,0.69ug/L(占总量的15~27%),分布较为均匀,证实了痕量金属离子(自由离子及不稳定络离子的均匀分布规律。有机结合态Zn,Cd及Pb(10~30%)和颗粒态Zn,Cu和Cu(15~40%)的较高含量位于长江口、东海及图们江口。 相似文献