Radiation—measurement complex of the Sirius synchrotron

The radiation-measurement complex associated with the Sirius synchrotron has been operating in the Scientific-Research Institute of Nuclear Physics of the S. M. Kirov Polytechnic Institute in Tomsk since 1985. Research on meson physics, channeling of high-energy electrons in crystals, new types of radiation, and applications of synchrotron radiation is carried out in this complex. The renovation of the synchrotron presently under way will allow these problems to be studied more effectively.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 5–7, June, 1991.     

Addition of some aminoheterocycles to N-benzyl-3-cyanopyridinium chloride

5-Aminopyrazoles react with N-benzyl-3-cyanopyridinium chloride giving 1-benzyl-3-cyano-4-(5-aminopyrazol-4-yl)-1,4-dihydropyridines with high regioselectivity. 5-Aminoisoxazole, 2-aminothiazole and 6-aminouracil react analogously.     

Acylation of 6,7,8,9-tetrahydro-5<Emphasis Type="Italic">H</Emphasis>-[1,2,4]triazolo-[4,3-<Emphasis Type="Italic">a</Emphasis>]azepin-3-ylacetonitrile

6,7,8,9-Tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-3-ylacetonitrile reacts with carboxylic acid anhydrides and chlorides to afford acylation products at the nitrogen atom in the heteroring or methylene carbon atom, depending on the conditions and nature of the acylating agent. Heating of the N-acyl derivatives leads to migration of the acyl group with formation of C-acyl derivatives.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1858–1860.Original Russian Text Copyright © 2004 by Makei, Volovenko, Nazarenko, Tolmachev.     

Extension of photonic band gaps in one-dimensional photonic crystals

A method is proposed for extending photonic band gaps by constructing periodic structures from two or more consecutively located photonic crystals with different lattice constants or filling factors. The photonic band gaps with a maximum extension are predicted by superposing the photonic band gap maps on one another. It is demonstrated that both the lowest and higher order band gaps can be merged in photonic crystals with a high refractive index contrast.     

Nonuniform distribution of absorbed energy in high-resistance materials excited by an electron beam

Experimental results are presented on the changes in the optical characteristics of lithium fluoride induced by an electron beam with time-varying density and pulse energies close to the threshold for destruction of the material. The spatial distribution of color centers is investigated, especially near breakdown channels. Mechanisms for nonuniform accumulation of defects are discussed, along with the fundamental causes of the inhomogeneous energy distributions induced by the high-current electron beam. Concrete results of calculations of the field intensity distribution in LiF crystals during irradiation are presented, based on models of “uniform” and nonuniform charging of the sample. An abrupt increase in the electric field intensity is predicted near the breakdown channel. Zh. Tekh. Fiz. 68, 53–59 (April 1998)     

Substituted 2-methyl-and 2-methyleneindolines 4. Hetaryl-condensed 2-methyl- and 2-methyleneindolines with a linear structure

Methods have been developed for the synthesis from amino-substituted indolines of first linear trinuclear hetaryl-condensed2-methyleneindolines having quinolone, quinoline, quinoxaline, and benzmidazole fragments. The structure of the obtained compounds was confirmed by ¹H and ¹³C NMR spectra.For communication 3, see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1331–1335, October, 1992.     

Mesoionic compounds with a bridged nitrogen atom. 5. π-electron structure of thiazolo[3,2-α]pyridinium 3-oxide derivatives

The -electron structure of thiazolopyridinium derivatives was analyzed thoroughly by the methods of quantum chemistry in order to ascertain the reason for the development of colors in the case of mesoionic compounds.See [1] for communication 4.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1618–1623, December, 1980.     

Pyrylocyanines. 23. 2-Pyrylocarbocyanines with substituents in hetero residues

Symmetric 2-pyrylo- and asymmetric (indo)(2-pyrylo)trimethinecyanines with substituents of different electronic nature in the pyran residue were synthesized. The influence of the conjugation effect and inductive effect on the characteristics of absorption bands of the synthesized dyes was analyzed by a quantum chemical calculation according to a common MO Hückel method.For Communication 22, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii No. 12, pp. 1607–1613, December, 1986.