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921.
The reactive 1:1 intermediate produced in the reaction between isocyanides and dialkyl acetylenedicarboxylates was trapped with 1,2-diacylhydrazines to yield highly functionalized pyrazoles in good yields. 相似文献
922.
In this paper the analytical equation of state (EoS) proposed by Ihm‐Song‐Mason was applied to calculate molar volume of mixtures of carbon dioxide with nitrogen and methane. The pair interaction potential has been used to evaluate the second virial coefficients and the ISM EoS parameters (i.e. α and b). The calculated values of the aforesaid quantities were applied to predict the molar volumes for mixtures of carbon dioxide with nitrogen and methane. Agreement with experiment was excellent for both mixtures. 相似文献
923.
We prove that smooth maps are dense in the sense of biting convergence in W
1, 1(M, N) when M and Nare compact Riemannian manifolds and N is closed. 相似文献
924.
JPC – Journal of Planar Chromatography – Modern TLC - Thin-layer chromatography of ten metal ions has been performed on pure soil layers; the mobile phases were aqueous organic and... 相似文献
925.
The purpose of this paper is to develop a fast and sensitive spectrophotometric method for the simultaneous determination of zinc(II), manganese(II) and iron(II) in pharmaceutical preparations. The method presented in this work is based on the well-known reaction of these ions with 4-(pyridylazo)resorcinol (PAR)1. The application of quantitative chemometric methods, particularly PLS to multivariate chemical data is becoming more widespread owing to the availability of digitized spectroscop… 相似文献
926.
927.
928.
Summary A TLC method has been developed for the separation of Zn(II) from Cd(II) and Cu(II) on silica gel alyers with mixed organic solvents containing s-butylamine. The separation of Zn(II) from Cd(II) in the presence of certain anions and at various pH values of sample solution was examined. A mixture containign s-butylamine, acetone and formic acid in 262 was found to be the best solvent. 相似文献
929.
Mohammad Q. Hailat 《Journal of Combinatorial Theory, Series A》1985,40(2):342-348
Unbounded symmetrysets R Zpn are introduced which, in the presence of a Jacobi condition, are classified and can be written as R = Zpn1 + + Zpnk (inner direct sum), where ni n for all i = 1, , k. The properties of these unbounded symmetrysets are easily verified for the set R of roots of Witt Lie algebras. This paper is a step in the direction of classifying simple Lie algebras of characteristic, p, by studying their rootsystems. 相似文献
930.
Majid Moghadam Iraj Mohammadpoor-Baltork Valiollah Mirkhani Shahram Tangestaninejad Mohammad Abdollahi-Alibeik Behrooz H. Yousefi Hadi Kargar 《Monatshefte für Chemie / Chemical Monthly》2007,33(3):579-583
Small assemblies of 2-imidazolines and bisimidazolines from appropriate nitriles and ethylenediamine with catalytic amounts
of P2S5 employing a microwave assisted protocol were prepared. Sonication of this system also led to successful synthesis of 2-imidazolines
and bisimidazolines. Another advantage of these systems is the ability to carry out large scale reactions. 相似文献