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为提高土壤多元素同时检测的效率,采用超级微波消解-电感耦合等离子体发射光谱法测定土壤中钾、钠、钙、镁、铜、铁、锰、锌、磷、硫、硼、砷、镉、铬、铅、钴、镓、锂等18种元素含量。比较了超级微波消解、常规微波消解和电热板消解的处理效果,采用超级微波消解法对样品进行前处理,并优化了消解条件。在最优条件下,各元素的检出限在0.05~20 mg/kg,加标回收率在86.2%~107.5%,RSD在0.1%~3.0%,方法准确度及精密度可以满足多元素同时测定的需求,且该方法具有简单、快速、成本低、用酸量少、重现性好等特点。 相似文献
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V. B. Krylov N. E. Ustyuzhanina A. A. Grachev N. A. Ushakova M. E. Preobrazhenskaya Yu. A. Shchipunov J. Wang M. H. Kim I. Kim N. E. Nifantieva 《Russian Chemical Bulletin》2011,60(12):2572-2578
Three hyperbranched dendrimers (polyglycidols) and the corresponding sulfated derivatives, differing in the average molecular weight, were synthesized. The compounds obtained were characterized in detail by mass spectrometry and 1H and 13C NMR spectroscopy, enabling estimation of the sizes of the corresponding molecules. Assignment of signals and identification of key structural blocks were performed using 2D homo- and heteronuclear spectroscopy (COSY, HSQC). The spectra of the sulfated derivatives showed the absence of the signals for the glycerol moiety with the free OH groups, that confirms exhaustive sulfation. The studies of antiinflammatory and anticoagulant activities of the polyanionic samples showed that all the compounds manifest weak antiinflammatory activity, however, their anticoagulant activity displayed in preliminary trials seems to be considerable. The results obtained indicate that it is reasonable to study in more detail biological activity of sulfated dendrimers of this type in terms of their anticoagulant properties. 相似文献
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It is shown that micellar surfactant solution with solubilized luminophore dye luminol can be used to synthesize silicate nanocomposite with luminescent properties. In the course of its synthesis, micelles perform a dual role, i.e., they solubilize luminol in neutral media, in which it is poorly soluble, and catalyze the sol-gel process, as well act as a template for the silicate forming in situ. It is established that, upon the incorporation of dye into the silicate matrix, its luminescent properties not only retained, but the intensity of fluorescence increases substantially. It is suggested that the approach developed can be used to produce biosencors since, along with dye, it permits us to immobilize enzymes. 相似文献
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The overlap of magnetization of the giound state in a RKKY spin glass system with the Dzyaloshinsky-Moriya interaction is studied based on the theory of infinite number of order parameter. It is shown that the nonmagnetic impurities are coupled with the host lattice.The results are in good agreement with experiments. 相似文献
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In this paper we study the dispersion relation of thermal non-neutral plasma column by MHD theory. We use the dispersion relation to discuss the stability and dispersive properties in a non-neutral plasma-filled waveguide. The results are in agreement with those of cold non-neutral plasma. 相似文献
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