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龙爪芦荟和库拉索芦荟中微量锗的测定与红外光谱区别 总被引:1,自引:0,他引:1
采用吸光光度法对龙爪芦荟和库拉索芦荟中的微量锗进行了测定,并探讨了两种芦荟的红外光谱的区别。结果表明,龙爪芦荟中含锗量在26.1~28.6μg·g-1,回收率为91.6%~97 5%。库拉索芦荟中含锗量在16.8~20.0μg·g-1,回收率为87.1%~94.5%。两种芦荟的FT IR光谱图在2100cm-1处有明显差异,由此可区别两种芦荟。 相似文献
124.
S. B. Brichkin M. A. Kurandina T. M. Nikolaeva V. F. Razumov 《High Energy Chemistry》2004,38(6):373-381
The spectral and luminescence properties of an anionic carbocyanine dye were studied under various conditions. These properties were shown to depend on the solvent polarity and additives introduced such as KBr, gelatin, and surfactants. It has been established that the effects of different surfactants (cationic CTAB, anionic SDS, AOT, and nonionic Triton X-100) on the spectral behavior of the dye in solutions are very individual and exhibit a number of features, which cannot be reduced to the rule below CMC–above CMC. 相似文献
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A rapid and facile synthesis of N-substituted 2,3,3a,4,7,7a-hexahydroisoindole-l,3-dione derivatives via microwave-promoted Beller three-component domino reaction of α,β,-unsaturated aldehydes, amides and N-substituted maleimides was described. 相似文献
127.
This paper is a continuation of the authors recent work [Beir?o da Veiga, H.and Yang, J., On mixed pressure-velocity regularity criteria to the Navier-Stokes equations in Lorentz spaces, Chin. Ann. Math., 42(1), 2021, 1–16], in which mixed pressure-velocity criteria in Lorentz spaces for Leray-Hopf weak solutions of the three-dimensional NavierStokes equations, in the whole space R~3 and in the periodic torus T~3, are established. The purpose of the present work is to extend the result of mentio... 相似文献
128.
Abalyaeva V. V. Nikolaeva G. V. Efimov M. N. Efimov O. N. Dremova N. N. Karpacheva G. P. Muratov D. G. 《Russian Journal of Applied Chemistry》2020,93(11):1667-1674
Russian Journal of Applied Chemistry - A method has been developed for synthesis of a composite coating based on polyaniline by introducing dispersed IR-pyrolyzed polyacrylonitrile, activated by... 相似文献
129.
A method of synthesis of ammonia cyclometalated Pt(II) complexes [Pt(NH3)2C∧N]ClO4, where C∧N is 2-phenylpyridinate or 2-phenylbenzothiazole ion, is developed. The electronic absorption and emission properties of the complexes are studied. It is found that the state responsible for intense long-lived luminescence is the excited charge-transfer state of the 3(d-π*) type, the π* orbital being localized at the corresponding cyclometalating ligand. Formation of platinum blue is observed in air-saturated aqueous solutions of ammonia cyclometalated complexes. 相似文献
130.
A polynomial expansion is proposed as a new way to discretize the Griffin-Wheeler-Hartree-Fock equations of the Generator Coordinate Hartree-Fock method. The implementation of the polynomial expansion in the Generator Coordinate Hartree-Fock method discretizes the Griffin-Wheeler-Hartree-Fock equations through a numerical mesh which is not equally spaced. This procedure makes the optimization of Gaussian exponents in the Generator Coordinate Hartree-Fock method more flexible and more efficient. The results obtained with the polynomial expansion for atomic Hartree-Fock energies show this technique is very powerful when employed in the design of compact and high accurate Gaussian basis sets used in ab initio non-relativistic (Hartree-Fock) and relativistic (Dirac-Fock) calculations. 相似文献