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21.
Journal of Experimental and Theoretical Physics - We study the stability of a convective flow in a nonuniformly rotating plasma layer in an axially uniform magnetic field. The stationary and...  相似文献   
22.
The formation of the previously unknown [(C5H4CPh2)2Ru]2+ dication was established by1H and13C NMR spectroscopy. This cation readiiy hydrolizes to form the monocation, [Ph2(HO)CC5H4RuC5H4CPh2]+. The latter was characterized by NMR spectroscopy and X-ray structural analysis. For comparison, [C5H5RuC5H4CPh2]+PF6 ? was also studied by X-ray structural analysis. The increase in the M-Cα distance and the decrease in the angle of inclination of the CPh2 group to the metal atom in disubstituted ruthenocene compared to those in monosubstituted ruthenocene is related to the presence of a bulky substituent in the second Cp ligand and is likely due to the crystal packing effect. IR spectra and X-ray structural analysis attest to the existence of the OH ? OSO2CF3 hydrogen bond in crystals of the trifluoromethanesulfonate monocation.  相似文献   
23.
Protonation of the [closo-3,3-(4-C10H12)-1-(CH2OH)-3,1,2-RhC2B9H10] PPN+ (C10H12 — dicyclopentadiene, PPN+ — bis(triphenylphosphine)iminium cation) at the ethylene bond of the norbornene moiety yields the neutralcloso-3,3,3-(-C10H13)-1-(CH2OH)-3,1,2-RhC2B9H10 with an agostic C-H...Rh bond. On prolonged storage in EtOH, the latter complex is converted intocloso-3,3-(3,2-C10H11)-1-(CH2OH)-3,1,2-RhC2B9H10 with -allylolefinic type coordination. Its crystal structure as dimeric aggregates with O-H...O and O-H...Rh bonds was determined by X-ray diffraction.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 776–778, April, 1995.  相似文献   
24.
A series of aroxytetraphenylstiboranes, Ph4SbOAr, were obtained by the reaction of pentaphenylstiborane with phenols at 20 °C. The thermolysis of these compounds givesO- or o-C-phenylation products. The thermolysis of stiboranes, which incorporate aryl groups containing electron-withdrawing substituents (Ar=2,4-Br2, 2,4-Cl2, 2-NO2, 4-OPh) produces predominantly simple diaryl ethers of asymmetric structure in 58 %, 90 %, 32 %, and 60 % yields, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 958–963, May, 1995.  相似文献   
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Diyne FcCmCC.CFc (Fc is ferrocenyl) reacts with Ru3(CO)12 in boiling hexane to yield binuclear complexes Ru2 and Ru2(CO)6(C4Fc2(C=CFc)2C=O) containing ruthenacyclopentadiene and diruthenacycloheptadienone rings, respectively. The isomerism of the complexes is due to the different ways of coupling of the alkyne fragments of the diyne, namely, head-to-head, head-to-tail or tail-to-tail. The reaction of enyne PhC=CCH=CHPh with Ru3(CO)12 under similar conditions gives isomeric binuclear complexes Ru2(CO)6(C4Ph2(CH=CHPh)2) and trinuclear clusters Ru3(CO)6(w-CO)2(C4Ph2(CH=CHPh)2) and Ru3(CO)8(3-,1-1-4-2 C4Ph2(CH=CHPh)2). The structure of the latter was determined by X-ray diffraction analysis. The Ru3 triangle coordinates eight terminal CO groups and the organic ligand resulting from the head-to-head dimerization of enyne molecules; the ruthenacyclopentadiene moiety is 4-coordinated to the Ru(CO)2 group, and the third ruthenium atom is 2-bound to one of the PhCH=CH groups.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1261–1267, May, 1996.  相似文献   
27.
The previously synthesized mixture of diastereomeric complexescloso-3,3-(η2,3-C7H7CH2)-1-(PhCH2)-3,1,2-RhC2B9H10 was separated by TLC on silica gel into individual diastereomers, whose stereochemistry and relative configurations were determined by X-ray diffraction analysis. Triplet- and quadruplet-like signals are marked with an asterisk Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2069–2070, November, 1997.  相似文献   
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Quantum-chemical calculations of the properties of a B+ ion-implanted SiO2/Si(100) interface are presented. Dependencies of the total energy of a B+ ion cluster system on the location of B+ ions in oxygen and silicon vacancies are calculated, along with the geometric and electronic characteristics of the equilibrium cluster states with implanted boron ions.  相似文献   
30.
We consider the motion of a composite charged particle in a constant electric field. Using the billiard formalism, we establish exact laws of motion for such a particle with a small number of internal degrees of freedom and propose using a generalized Schwarz principle to straighten trajectories in the field presence. Within the billiard formalism, we obtain regimes of motion of a composite particle with two internal degrees of freedom in a constant field.  相似文献   
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