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海水中无机物的光化学反应   总被引:5,自引:0,他引:5  
综述了近几十年来国内外关于海水中无机物的光化学反应的研究状况。首先,阐述了海洋光化学在海洋科学中的重要性,历年来的发展状况以及海水的光化学与其它相关领域之间的相互影响作用。其次,本文分别从阴离子的光化学反应,阳离子的光化学反应和过氧化氢的光化学反应三个方面对海水中无机物的光化学反应进行了论述,详细介绍了铁、锰、铜、汞、过氧化氢、硝酸盐和碘化物随反应介质、温度、酸碱度、有机物浓度和光照等外界因素的不同而发生的光化学反应的变化。另外,讨论了上述物质发生光化学反应的主控因素及其在反应过程中对周围环境的影响作用,并对部分物质的反应机理作了介绍。最后,本文指出了这一研究领域存在的问题和不足,并提出今后的研究建议。  相似文献   
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The availability of phosphorus to juvenile abalone,Haliotis discus hannai from primary, secondary and tertiary calcium phosphate, primary sodium or potassium phosphate separately or in combination was determined in a 120-day feeding trial. Seven semi-purified diets were formulated to contain relatively constant dietary phosphorus, ranging from 0.78%–0.82%. The concentrations of dietary phosphorus were presumed to be slightly below the requirement for abalone. A brown alga,Laminaria japonica, was used as a control diet. Abalone juveniles of silimar size (average weight 1.18 g; average shell length 18.74 mm) were distributed in a single-pass, flow-through system using a completely randomized design with eight treatments and three replicates each treatment. The survival ranged from 71.1% to 81.1%, and was not significantly (P>0.05) related to dietary treatment. However, the weight gain rate (41.72%–65.02%), daily increment in shell length (36.87–55.07 μm) and muscle RNA-DNA ratio (3.44–4.69) were significantly (P<0.05) affected by dietary treatment. Soft body alkaline phosphatase activity (10.9–19.8 U/g wet tissue) and carcass levels of lipid (7.71%–9.33%) and protein (46.68%–49.35%) were significantly (P<0.05) responsive to available phosphorus of the diets. Dietary treatment had significant effect (P<0.05) on concentrations of phosphorus in the whole body (WB) and soft body (SB). Apparent digestibility coefficients (45%–97%) of phosphorus were also significantly (P<0.05) different between dietary treatments. The results indicated that among these inorganic compounds, primary calcium, potassium and sodium phosphates separately or in combination could be utilized effectively by juvenile abalone as dietary phosphorus sources (availability ranging from 87%–97%). However, secondary and tertiary calcium phosphates were found to be low in availability, the values being 45% and 77%, repectively. Project 39670572 supported by the Natural Science Foundation of China (NSFC).  相似文献   
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粗看起来,治病与我们常见的石头是风马牛不相及的事情,然而,两者之间却有着千丝万缕的联系.大家知道,自古以来,中医经过"望、闻、问、切"之后,便要开药方用药.中国古代的药物学自成一个体系,历代皆称之为"本草".而中医药在其分类中包括了动物药、植物药和矿物药这三个基本的类别.历代本草上讲的矿物药是从广义上讲的,既包括了矿物和岩石等一些天然形成的无机物,也包括了一些古生物的化石和琥珀.下面介绍的是一些矿物、岩石和化石在中药里的名称,基本特征和用途,以开阔眼界,增长知识.  相似文献   
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电致化学发光法在分析化学中的应用   总被引:1,自引:0,他引:1  
本文概括地综述了近十几年来电致化学发光分析法在无机物、有机物及生物分析中的应用。引用文献52篇。  相似文献   
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Species and distribution of inorganic selenium in the Bohai Sea   总被引:1,自引:0,他引:1  
1 INTRODUCTION Selenium is a ubiquitous trace element that ex- ists in multiple chemical forms in seawater in dif- ferent oxidation states and organic metalloid com- pounds. Selenium is essential for the growth of various photosynthetic species in natural…  相似文献   
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Incubation experiments are carried out to study the exchange rates of dissolved inorganic nutrients including silicate, phosphate, ammonium, nitrite, and nitrate (^vSiO3-Si,^vPO4-P, ^vNH4-N, ^vNO2-N and ^vNO3-N) at the sediment-water interface in the Jiaozhou Bay. Major factors influencing the exchange rates are discussed in detail, which include the dissolved inorganic nutrient concentrations in porewater (Cpw), water and clay contents, and grain size of the sediments (CH2O, Cclay and GSsed). The results may provide insight into the dynamics of nutrient transport and the environmental capacity of nutrients in Jiaozhou Bay, and should be beneficial to solving the problems caused by excessive nutrient input this area.  相似文献   
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