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101.
《Soil Science and Plant Nutrition》2013,59(1):160-169
Abstract A pot culture experiment was conducted to investigate the effects of amorphous iron-(hydr)oxide (Am-FeOH) amendments on arsenic (As) availability and its uptake by rice (Oryza sativa L. cv. BR28) irrigated with As-contaminated water. A rhizobag system was established using 3.5 L plastic pots, each containing one central compartment for plant growth, a middle compartment and an outside compartment. Three levels of laboratory-synthesized Am-FeOH (0, 0.1 and 0.5% w/w) were used to amend samples of the As-free sandy loam paddy soil placed into each compartment of the rhizobag system. The soils were submerged with a solution containing 5 mg L?1 As(V). Two-week-old rice seedlings were planted in the central compartments and cultured for 9 weeks under greenhouse conditions. The addition of 0.1% Am-FeOH to the soil irrigated with As-contaminated water improved plant growth, reduced the As concentration in the plants and enhanced Fe-plaque formation on the root surfaces. Analysis of soil solution samples collected during the experiment revealed higher pH levels and lower redox potentials in the soils amended with Am-FeOH at the onset of soil submergence, but later the soil solution collected from the 0.1% Am-FeOH treatment was slightly acidic and more oxidized than the solution from the 0% treatment. This indicated active functioning of the roots in the soil treated with 0.1% Am-FeOH. The concentrations of As(III) in the soil solution collected from the central compartment were significantly reduced by the Am-FeOH amendments, whereas in the soil treated with 0% Fe, As(III) accumulated in the rhizosphere, particularly during the late-cultivation period. The improvement in plant growth and reduction in As uptake by plants growing in the Am-FeOH treated soil could be attributed to the reduction of available As in the soil solution, mainly as a result of the binding of As to the Fe-plaque on the root surfaces. 相似文献
102.
《Journal of plant nutrition》2013,36(8):1453-1463
ABSTRACT Iron (Fe) in the embryo fraction of soybean (Glycine max L.) seed is important for seedling growth. Seed Fe accumulation in 27 soybean genotypes differing in seed size was studied at two field locations. Mean seed weight was 148 mg seed?1 with mean individual genotypic values ranging from 68 to 217 mg seed?1. Percentage of total seed dry matter in the seed-coat fraction, which was inversely correlated with individual seed weight, was 8.2%, with mean individual genotypic values ranging from 7.0% to 12.4%. Mean seed-Fe concentration [Fe] was 65 μg Fe g?1, with individual genotypic values ranging from 48 to 81 μg Fe g?1. Seed Fe relative to dry-matter distribution was much more concentrated in seed coats than in embryos of all genotypes. Mean percentage of total seed Fe located in the seed-coat fraction was 29%, with mean genotypic values ranging from 23% to 38%. Neither seed-Fe characteristic was correlated with individual seed weight. Seed [Fe] was not correlated with seed-manganese (Mn) concentration [Mn]. Mean seed [Fe] for the 27 genotypes was different at the two locations, presumably due to differences in available soil Fe. Both genotype and environment affected seed [Fe] of soybean. Soybean seed coats, a major by-product after oil extraction, are a possible rich source of Fe for human nutrition. 相似文献
103.
本文通过体外消化来模拟消化系统以研究乳及发酵乳对FeCl3中铁的化学状态及透析率的影响,结果表明,在消化过程中乳及发醇乳可促进铁的溶解、以及Fe3 的还原和铁的透析,这一作用与样品的pH元失,认为是消化过程中产生的氨基酸和肽起了作用。研究还发现,原乳先加铁盐再送行发酵所产生的作用要较发醇后再加铁盐的作用大,认为发醇乳对铁化学状态及透析率的影响具有时间效应。此外,有乳存在的各试验组其Fe3 透析率较可溶性铁的透析率与对照组差异更大。 相似文献
104.
以甲苯-2,4-二异氰酸酯、丙烯酸羟乙脂、甲基丙烯酸缩水甘油酯等对树支状多元醇进行改性,合成了可快速光固化的新型树枝状聚氨酯丙烯酸酯树酯(DPUA),并通过红外光谱,核磁共振氢谱对其结构进行了分析表征.同时测试的结果表明:固化膜具有适当的硬度和柔韧性,较好的附着力,热分解温度可达到208℃. 相似文献
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109.
LIU Zheng-li SUN Shi-xian CHENG Ru-hong HUANG Wen-sheng LIU Jun-xin QU Zhu-feng XIA Xue-yan SHI Zhi-gang 《中国农业科学(英文版)》2006,5(7):558-562
Super Early Maturation No.2 is a new foxtail millet germplasm developed by using the targeted-character-gene-bank-breeding method. It has several outstanding characteristics. (1) Super early maturity. It can normally mature in Bashang, Hebei Province, China, where the altitude is around 1 400 meters, and it needs 1650°C of effective accumulated temperature in the growing period. (2) Millet is rich in iron. The iron content of the millet of Super Early Maturation No.2 is 54.10 mg kg−1, which is 62.0% higher than the average iron content of the foxtail millet varieties in China. (3) High crude fat content. Its crude fat content is 6.24%, which is 54.1% higher than the average content of foxtail millet varieties in China. (4) High crude protein content. The average of the crude protein content of all the foxtail millet varieties in China is 12.71%, only 5% varieties surpass 14%, however, the crude protein content of Super Early Maturation No.2 is 14.36%, which is rare in improved varieties of foxtail millet in China. (5) Overall characteristics are good. 相似文献
110.
E52-9环保型导静电防腐涂料的研制 总被引:2,自引:0,他引:2
针对大型石油储罐内防腐施工中存在易燃气体浓度超标、露点影响区覆盖层的附着力下降、油罐焊缝部位的腐蚀等问题,研制出了一种新型的E52—9环保型导静电防腐涂料,从成膜基料、无毒溶剂、抗静电剂及导电填料、E52多功能环氧树脂固化剂等方面详细介绍了该涂料的组成及特性,该涂料的应用可有效克服油罐内防腐施工中存在的问题。 相似文献