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LI Yu GAO Qian WANG Xiao-li DONG De-ming WANG Ao . Energy Environmental Research Centre North China Electric Power University Beijing P. R. China . College of Environment Resources Jilin University Changchun 《高等学校化学研究》2009,25(2)
Co-contamination of atrazine(AT) and cadmium(Cd) on the surficial sediments(SSs) and natural suface coating samples(NSCSs) was investigated via thermodynamic adsorption experiments. The results show that surface coatings have a stronger ability to adsorb AT owing to their higher active components compared with surficial sediments. Synergetic and antagonistic effects of Cd on the adsorption of AT were observed. Cd at a lower concentra- tion(≤4.0 mg/L) in the solid/liquid phase enhanced AT adsorption onto the... 相似文献
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应用ICP—MS测定KCl肥料中重金属元素含量 总被引:7,自引:0,他引:7
肥料是重金属的重要污染源之一,重金属可以通过作物直接进入人类食物链对人体产生危害,研究肥料中重金属含量对于农产品安全溯源意义重大。文章选用北京市场上销售的进口KCl肥料作为实验材料,全面分析了其中的10种重金属元素含量,分别为,Cr0.00,Ni65.54,Cu238.85,As190.60,Cd0.98,Sn14.98,Sb2.97,Hg10.04,Tl1.28,Pb97.42ng·g-1。上述结果表明,KCl肥料中重金属含量普遍比较低,特别是Cr没有检测到,其余四中主要重金属(As,Cd,Hg,Pb)的含量除了As(190.60ng·g-1)以外,也都在100ng·g-1以下,不会对土壤环境造成重大污染,含量最高的重金属是Cu,为238.85ng·g-1。由此看来,KCl肥料与磷肥相比重金属含量较低,对农产品是相对安全的。 相似文献
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XRF分析黄金首饰中的主,次元素—修正比例常数法 总被引:3,自引:2,他引:1
本文创造了一套金合金标准,用XRF法分析黄金首饰中的主、次元素。发展了基体校正理论。进一步修正和完善了比例常数法的原理。汇编了一个专用的计算机程序。提出了一个新的分析方法。作者指出,本法比基本参数法更优越,有更好的发展前景。 相似文献
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Average life of oxygen vacancies of quartz in sediments is estimated by using the ESR(electron spin resonance) signals of E' centers from the thermal activation technique. The experi-mental results show that the second-order kinetics equation is more applicable to the life estima-tion compared with the first order equation. The average life of oxygen vacancies of quartz from4895 to 4908 deep sediments in the Tarim Basin is about 10~(18) a at 27℃. 相似文献
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Through embryo culture, intergeneric hybrids were produced between common wheat,Triticum aestivum cv. Chinese Spring (CS) (2n= 6x = 42, AABBDD) and crested wheatgrass,Agropyron desertorum (2n =4x =28, PPPP) for the first time. Their F_2 and BC_1 seeds havealso been successfully obtained by selfing and backcrossing with wheat in F_1 hybrids. Theseedlings of all F_1 hybrids tended to resemble their female parent, but they had more tillers,and their spike characteristics were between their parents. Average meiotic chromosomepairing at MI of F_1 hybrids was: 6.62Ⅰ+ 8.20RingⅡ+ 4.16RodⅡ+0.57Ⅲ+ 0.35Ⅳ+0.06Ⅴ+0.03Ⅵ. The successful experience of hybridization of common wheat with A. desertorum,the reason for the high level of chromosome pairing and self-fertility in the F_1 hybrids werediscussed. The F_2 and BC_1 seeds obtained in F_1 hybrids are of great importance to theory andpractice. 相似文献
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以杂多酸形式光度法测定磷的进展 总被引:4,自引:0,他引:4
磷的测定方法中,目前光度法所占的比例还比较大。分析化学工作者已对磷钼二元杂多酸、磷钼二元杂多酸与另外一些元素形成的三元杂多酸的反应机理及光度法测定磷的分析应用进行了广泛研究,使得以磷钼杂多酸形式光度法测定磷比较成熟和普及。这类方法简单准确、使用方便、易于实现自动化、不仅用于痕量也用于高含量磷的测定。 相似文献
77.
郑在胜 《中国科学B辑(英文版)》1991,(1)
On the basis of the variation in the energies which are different in a transfer styleduring rock deformation and the new classification of microdeformation mechanism of rock,we have divided the deformation styles into three types. According to the characteristics ofdeformation dynamics of rock (DDR), we have established a mathematical model of DDRand obtained the solutions of the differential equation of the mathematical model and the de-formation style of rock (DSR). It is shown that there may be a spatio-temporal ordereddissipative structure during rock deformation. Our conclusions coincide with the result oractual process of rock deformation. 相似文献
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Nor Aishah Saidina Amin Didi Dwi Anggoro. Faculty of Chemical Natural Resources Engineering Universiti Teknologi Malaysia Skudai Johor Malaysia. Department of Chemical Engineering University of Diponegoro Semarang IndonesiaManusc 《天然气化学杂志》2002,(Z1)
Ethylene oligomerization using ZSM-5 zeolite was investigated to study the role of Bronsted acid sites in the formation of higher hydrocarbons. The oligomerization of olefins, dependent on the acidity of ZSM-5 zeolite, is an important step in the conversion of natural gas to liquid fuels. The framework Si/Al ratio reflects the number of potential acid sites and the acid strength of the ZSM-5 catalyst. ZSM-5 with the mole ratio SiO2/Al2O3 equal to 30 was dealuminated for different periods of time according to the acidic ion-exchange method to produce ZSM-5 with various Si/Al ratios. The FT-IR analysis revealed that the integrated framework aluminum band, non-framework aluminum band, and silanol groups areas of the ZSM-5 zeolites decreased after being dealuminated. The performance of the dealuminated zeolite was tested for ethylene oligomerization. The results demonstrated that the dealumination of ZSM-5 led to higher ethylene conversion, but the gasoline selectivity was reduced compared to the performance 相似文献