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141.
Acrylonitrile reacts with aromatic aldehyde imines containing a hydroxy group in the β- or γ-position to give 70–85% of the corresponding 2-aryl-3-cyanoethyltetrahydro-1,3-oxazines or 2-aryl-3-cyanoethyl-1,3-oxazolidines, respectively. The results of these reactions are rationalized in terms of ring-chain isomerism of the initial imines.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1064–1066.Original Russian Text Copyright © 2005 by Kon’kova, Abovyan, Khachatryan, Badasyan, Panosyan, Sargsyan.  相似文献   
142.
Quantum diffusion equations featuring explicitly time-dependent transport coefficients are derived from generalized non-Markovian Langevin equations. Generalized fluctuation-dissipation relations and analytic expressions for calculating the friction and diffusion coefficients in nuclear processes are obtained. The asymptotic behavior of the transport coefficients and correlation functions for a damped harmonic oscillator that is linearly coupled in momentum to a heat bath is studied. The coupling to a heat bath in momentum is responsible for the appearance of the diffusion coefficient in coordinate. The problem of regression of correlations in quantum dissipative systems is analyzed.  相似文献   
143.
Free‐base and nickel porphyrin–diaminopurine conjugates were formed by hydrogen‐bond directed assembly on single‐stranded oligothymidine templates of different lengths into helical multiporphyrin nanoassemblies with highly modular structural and chiroptical properties. Large red‐shifts of the Soret band in the UV/Vis spectroscopy confirmed strong electronic coupling among assembled porphyrin–diaminopurine units. Slow annealing rates yielded preferentially right‐handed nanostructures, whereas fast annealing yielded left‐handed nanostructures. Time‐dependent DFT simulations of UV/Vis and CD spectra for model porphyrin clusters templated on the canonical B‐DNA and its enantiomeric form, were employed to confirm the origin of observed chiroptical properties and to assign the helicity of porphyrin nanoassemblies. Molar CD and CD anisotropy g factors of dialyzed templated porphyrin nanoassemblies showed very high chiroptical anisotropy. The DNA‐templated porphyrin nanoassemblies displayed high thermal and pH stability. The structure and handedness of all assemblies was preserved at temperatures up to +85 °C and pH between 3 and 12. High‐resolution transition electron microscopy confirmed formation of DNA‐templated nickel(II) porphyrin nanoassemblies and their self‐assembly into helical fibrils with micrometer lengths.  相似文献   
144.
1,1-Di(prop-2-yn-1-yl)-2,5-dihydro-1H-Pyrrol-1-ium bromide was obtained with interaction of 3-pyrroline with propargyl bromide and its structure was studied by X-ray analysis. It has been shown that the Stevens rearrangement of obtaining salt leads to the formation of 1-(hexa-4,5-dien-1-yn-3-yl)-2,5-dihydro-1H-pyrrol.  相似文献   
145.
Isotopic dependences of the capture cross section and the mean and mean-square angular momenta of a captured system in the 16O, 48Ca + 196,200,204,208Pb and 16O + 152,154Sm reactions are investigated using the quantum diffusion approach. The obtained results are in good agreement with the existing experimental data.  相似文献   
146.
We show that it is consistent, relative to nω supercompact cardinals, for the strongly compact and measurable Woodin cardinals to coincide precisely. In particular, it is consistent for the first n strongly compact cardinals to be the first n measurable Woodin cardinals, with no cardinal above the nth strongly compact cardinal being measurable. In addition, we show that it is consistent, relative to a proper class of supercompact cardinals, for the strongly compact cardinals and the cardinals which are both strong cardinals and Woodin cardinals to coincide precisely. We also show how the techniques employed can be used to prove additional theorems about possible relationships between Woodin cardinals and strongly compact cardinals. The first author's research was partially supported by PSC-CUNY Grant 66489-00-35 and a CUNY Collaborative Incentive Grant.  相似文献   
147.
148.
Given a continuous function on [0,1], it is always possible to alter its values on a small set so that the modified function is continuous and has an expansion which converges unconditionally in C[0,1].  相似文献   
149.
150.
We establish two theorems concerning strongly compact cardinals and universal indestructibility for degrees of supercompactness. In the first theorem, we show that universal indestructibility for degrees of supercompactness in the presence of a strongly compact cardinal is consistent with the existence of a proper class of measurable cardinals. In the second theorem, we show that universal indestructibility for degrees of supercompactness is consistent in the presence of two non-supercompact strongly compact cardinals, each of which exhibits a significant amount of indestructibility for its strong compactness. The first author’s research was partially supported by PSC-CUNY grants and CUNY Collaborative Incentive grants. The first author wishes to thank James Cummings for helpful discussions on the subject matter of this paper. In addition, both authors wish to thank the referee, for many helpful comments and suggestions which were incorporated into the current version of the paper.  相似文献   
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