On 0-homology of categorical at zero semigroups

The isomorphism of 0-homology groups of a categorical at zero semigroup and homology groups of its 0-reflector is proved. Some applications of 0-homology to Eilenberg-MacLane homology of semigroups are given.      

Convenient synthesis of dodeca-1,3-diynyl ketones by the “diacetylene zipper” reaction

Dodeca-1,3-diynyl ketones were synthesized by isomerization of dodeca-5,7-diyne with H₂N(CH₂)₂NHLi and treatment of the in situ prepared lithium derivative of dodeca-1,3-diyne with N-methoxy-N-methylcarboxamides. Dedicated to Corresponding Member of the Russian Academy of Sciences E. P. Serebryakov on the occasion of his 70th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 1017–1019, April, 2005.     

Strained iminium ylides

Quantum-chemical calculations were used to analyze the chemical behavior of strained iminium ylides containing a three-membered ring either incorporated in a 1,3-dipole or as a substituent.     

Synthesis of new amidophosphates containing an adamantyl fragment under microwave irradiation

The reaction of amines containing an adamantly fragment with diethyl phosphite in tetrachloromethane in the presence of triethylamine was studied under the microwave irradiation.     

Polarization transformers for optical anisotropy: I. Nonreciprocal optical systems and the equivalence theorem

The problem of transformation of anisotropic properties of multipass nonreciprocal systems is considered. The equivalence theorem is generalized to the case of nonreciprocal elements (i.e., to elements that do not satisfy the equivalence theorem). It is shown that any nonreciprocal anisotropic phase element is equivalent to a combination of five elements, namely, a reciprocal linear phase plate, a nonreciprocal linear phase plate, a reciprocal rotator, and two Faraday rotators. The difference between reciprocal and nonreciprocal elements is considered from the viewpoint of their basis states.     

Blue emission from arsenic doped gallium nitride

We have observed strong blue emission at room temperature from arsenic doped GaN samples grown by molecular beam epitaxy. Similar results were obtained for samples doped with both arsenic dimers and tetramers. The origin of this blue emission is discussed and a growth model proposed to account for our observations. We propose that arsenic doped GaN may be a suitable replacement for (InGa)N as the active region for blue light emitting devices.     

Unusual relaxation process in polybutadiene: Resolving the controversy

We report the observation of an unusual relaxation process in depolarized light scattering spectra of polybutadiene (PBD) with two different vinyl contents. The process showed up in the gigahertz frequency range with relatively mild temperature dependence and was similar to a secondary relaxation process. The most surprising observation was that the process exists even at high temperatures and does not merge with the segmental relaxation up to a temperature of 400 K (T > 2T_g). Possible mechanisms of this particular relaxation in PBD are discussed. The process is compared to the so‐called E process, double‐bond hopping process, and dielectric β process. We emphasize that this process differs from the dielectric β process, is unique for 1,4‐PBD, and has not been observed in other polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 994–999, 2004     

Self-organization of germanium nanoislands obtained in silicon by molecular-beam epitaxy

Nanometer germanium islands in epitaxial layers of silicon are obtained by molecular-beam epitaxy. The dimensions and shapes of the islands are determined in an atomic-force microscope. The photoluminescence spectra are found to contain lines that can be interpreted as quasidirect optical transitions in the islands. It is concluded on the basis of optical and microprobe measurements and theoretical calculations of the energies of electronic states that silicon is dissolved in the germanium islands. Values of the germanium and silicon contents in the solid solution are presented. Pis’ma Zh. éksp. Teor. Fiz. 67, No. 1, 46–50 (10 January 1998)     

A graphite oxide-based nickel catalyst for reductive dechlorination of polychlorinated aromatic hydrocarbons

Heterogeneous Ni-containing catalysts based on graphite oxide were prepared and their activity in the dechlorination of polychlorinated aromatic hydrocarbons by different organosilanes was studied. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1023–1025, June, 2000.