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1.
A method is proposed for the synthesis of porphyrins based on the cyclization of a tetrapyrrole system with methyl and formyl groups at the ends of the molecule. The synthesis of mesoporphyrin IX and diacetyldeuteroporphyrin IX has been effected.  相似文献   
2.
New test tools have been developed for the rapid determination of trace metals: Ag, Cd, Co, Cu(II), Fe(II,III), Hg(II), Pd and Zn, using polydentate irregular α-celluloses, containing in the 6 position the fragments heterylformazane or heterylhydrazone, with a pocket device for preconcentration. Received: 17 June 1997 / Revised: 1 November 1997 / Accepted: 6 November 1997  相似文献   
3.
Eight amino derivatives of thiophene analogs of chalcone were obtained by reduction of the corresponding nitro derivatives with stannous chloride in concentrated hydrochloric acid, and their UV absorption spectra in dioxane were measured. The long-wave band was assigned to the corresponding fragments of the molecule on the basis of a comparison of the absorption curves of the investigated compounds with the curves of simpler compounds — aminoacetophenone, aminobenzalacetone, acetothienone, etc.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 198–203, February, 1977.  相似文献   
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We demonstrate that a Bose-Einstein condensate in an optical lattice forms a reconfigurable matter-wave structure with a band-gap spectrum, which resembles a nonlinear photonic crystal for light waves. We study in detail the case of a two-dimensional square optical lattice and show that this atomic band-gap structure allows nonlinear localization of atomic Bloch waves in the form of two-dimensional matter-wave gap solitons.  相似文献   
6.
Ferrocenylalkyl thiopyrimidines ( 6a–d to 9a–d ) were prepared via the reaction of the α‐(hydroxy)alkyl ferrocenes, FcCHR(OH) ( 1a–d ; Fc = ferrocenyl; R = H, Me, Et, Ph), with 2‐thiopyrimidines ( 2 – 5 ) in acetone at room temperature in the presence of TFA, yielding 50–95%. The resulting enantiomers were resolved using HPLC on modified cellulose as chiral selector. The antitumor activities of S‐ferrocenylethyl 2‐thiopyrimidine ( 6b ) against two murine solid tumor models, carcinoma 755 (Ca755) and Lewis lung carcinoma (LLC) were evaluated in vivo. The strong antitumor effect of compound 6b on Ca755 and LLC was demonstrated. The index of tumor growth inhibition on Ca755 equaled 95% in comparison with control. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
7.
A stability analysis of the stationary rotation of a system of N identical point Bessel vortices lying uniformly on a circle of radius R is presented. The vortices have identical intensity Γ and length scale γ?1 > 0. The stability of the stationary motion is interpreted as equilibrium stability of a reduced system. The quadratic part of the Hamiltonian and eigenvalues of the linearization matrix are studied. The cases for N = 2,..., 6 are studied sequentially. The case of odd N = 2?+1 ≥ 7 vortices and the case of even N = 2n ≥ 8 vortices are considered separately. It is shown that the (2? + 1)-gon is exponentially unstable for 0 < γR<R*(N). However, this (2? + 1)-gon is stable for γRR*(N) in the case of the linearized problem (the eigenvalues of the linearization matrix lie on the imaginary axis). The even N = 2n ≥ 8 vortex 2n-gon is exponentially unstable for R > 0.  相似文献   
8.
Relationships for the efficiency of conversion of laser radiation energy to acoustic energy for the acoustooptic (thermal) mechanism of interaction are derived. The cases of short and long laser pulses interacting with the rigid and free boundaries of a heavily absorbing liquid are considered. The efficiency is numerically calculated for the situation when the radiation of a transverse-excitation atmospheric (TEA) CO2 laser interacts with water with regard for the temperature variation of the volume thermal expansion coefficient of the latter.  相似文献   
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Mono- and polychloromethyl derivatives were synthesized by chlorination of dimethylfurazan with chlorine and sulfuryl chloride. The PMR spectra of the compounds are discussed. The group refraction of the furazan ring, the average value of which is 12.78, was determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii,No. 1, pp. 30–32, January, 1977.  相似文献   
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