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161.
Reactions of 3-[(N-aryl-N-chloroacetyl)amino]-2-formylindoles with substituted anilines gave 1,4-diaryl-2-oxo-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indol-4-ium chlorides and those with 4-aminopyridine yielded 4-amino-1-(1-aryl-2-oxo-2,5-dihydro-1H-pyrido[3,2-b]indol-3-yl)pyridinium chlorides. Reduction of 1,2,3,6-tetrahydrodiazepinoindol-4-ium chlorides afforded the corresponding hexahydro derivatives. An alternative synthesis of 1-(4-nitrophenyl)-3-oxo-4-phenyl-1,2,3,4,5,6-hexahydro[1,4]diazepino[6,5-b]indole from 3-[N-(4-nitrophenyl)amino]-2-[(phenylimino)methyl]indole was developed. The method involves the following sequence of transformations: reduction, chloroacetylation, and intramolecular alkylation. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2193–2199, December, 2006.  相似文献   
162.
A new autooscillation chemiluminescence reaction of 4-oxyquinoline oxidation by bromate ions, catalyzed by cerium ions and tris-(2,2-dipyridine) ruthenium complexes, has been discovered.
4- , , -2,2- .
  相似文献   
163.
The equilibrium shape ofhcp 4He crystals has been studied at temperatures 0.05≤T≤0.7 K by means of a high precision optical interferometer. We find that the profile of the interfacial boundary, close to an almost horizontal c-facet, has a well-defined slope discontinuity separating two angular regions with different behavior of the surface stiffness. For surfaces tilted by an angle ϕ≤100 μrad with respect to the c-facet, we obtain, contrary to the linear angular dependence predicted by current theories.  相似文献   
164.
In a quasioptical approximation we develop a theory of an open cavity with a dielectric plate placed normally to the cavity axis. We find conditions under which some natural frequencies of the cavity are practically independent of the plate position in the cavity. From experimental measurements of one of these frequencies and with variation of the length of the cavity with and without the plate, with the same oscillation- mode structure, we determine the refractive index and plate thickness. Coincidence between the obtained (design) thickness and mechanically measured one is a correctness criterion for the results obtained.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 5, pp. 615–623, May, 1996.  相似文献   
165.
Much is known about the connection between the growth and decayof subharmonic functions. The results indicate that there isa general principle: asubharmonic function cannot decay ‘toofast’ relative to its growth.Three theorems are provedwhich, together with work previously published elsewhere, givea fairly complete account of how this principle works out fora subharmonic function having extremal decay along a ray. 1991Mathematics Subject Classification: 30D20, 31A05.  相似文献   
166.
The results of investigating the relative contribution of surface excitations to the reflection electron energy loss spectrum in pure silicon are presented. The primary electron energy is in the range 60–1000eV. Good agreement is obtained between the experimental values of the surface parameter P S and theoretical calculations. The relative contribution of surface excitations is also determined by decomposing the integral reflection electron energy loss spectra into Gaussian curves.  相似文献   
167.
The method of isotopic contrast in combination with inelastic neutron scattering has been used to investigate the vibrational spectrum of the copper atoms in Pr2CuO4. It is shown that the energy positions of the features of the vibrational spectrum of copper in Pr2CuO4 and CuO (which also has a planar oxygen coordination of copper) coincide. We conclude that the dynamical behavior of the copper atoms is formed mainly by their interaction with the nearest-neighbor oxygen atoms. Fiz. Tverd. Tela (St. Petersburg) 41, 1149–1153 (July 1999)  相似文献   
168.
We present the results of a theoretical and experimental study of a new phenomenon of total transformation of an electromagnetic wave incident from a dielectric on a corrugated boundary between two transparent dielectrics to a transmitting wave of the (-1)st-order harmonic propagating in the other dielectric. The theoretical study is based on numerical solution of the full-wave equations for electromagnetic field. The experimental study is made using a Teflon prism with a corrugated surface located in a two-mirror resonator.  相似文献   
169.
Raikov  I. O.  Conyuh  D. A.  Ipatov  A. N.  Parshin  D. A. 《Physics of the Solid State》2020,62(11):2143-2153
Physics of the Solid State - The effect of disorder in the distribution of force constants on optical and acoustic phonons in the scalar model of crystalline graphene is studied for both...  相似文献   
170.
Rudskoi  A. I.  Parshin  S. G. 《Doklady Chemistry》2021,499(2):168-170
Doklady Chemistry - The scientific and technological principles were presented for the production of electrochemical nanocomposites from a nickel matrix and lanthanum fluoride and boride on...  相似文献   
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