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101.
V. V. Sharutin A. P. Pakusina O. K. Sharutina I. V. Egorova M. A. Pushilin 《Russian Journal of Coordination Chemistry》2007,33(2):96-103
The reaction of pentaphenylantimony with mercury iodide affords the ionic complex [Ph4Sb] 2 + [Hg2I6]2?·Ph2Hg (I). The [Ph4Sb] 2 + [Hg2I6]2? (II) and [Ph4Sb] 2 + [Cd2I6]2? (III) complexes are synthesized from tetraphenylantimony iodide and mercury and cadmium iodides. The [Ph4Sb] 2 + [Hg4I10]2? complex (IV) is prepared from tetraphenylantimony 2,4-dimethylbenzenesulfonate and mercury iodide. According to the X-ray diffraction data, the Sb atom in the [Ph4Sb]+ cations of complex I has virtually ideal tetrahedral coordination (the CSbC angles are 108.09°–109.64°). In the central square fragment Hg2I2 of the [Hg2I6]2? anion, the Hg-Ibr bond lengths are 2.825 and 3.075 Å, and the terminal iodine atoms are more strongly bonded to the mercury atoms (Hg-Iterm 2.691 and 2.700 Å). The [Cd2I6]2? anion in complex III has a similar structure (the Cd-Ibridg and Cd-Iterm distances are 2.865, 2.872 and 2.723, 2.748 Å, respectively). The anions in complex IV are joined by I…Hg (3.651 Å) and I…I (4.058 Å) interactions into an infinite dimeric network. 相似文献
102.
Reactions of 5-substituted furan-2(3H)-ones with ethylenediamine, 2-aminoethanol, and o-aminophenol do not stop at the stage of formation of the corresponding 4-oxoalkanoic acid amides but lead to new bi-and tricyclic structures as a result of double intramolecular cyclodehydration. 相似文献
103.
We investigate the tail behavior of the sojourn-time distribution for a request of a given length in an M/G/1 Processor-Sharing
(PS) queue. An exponential asymptote is proven for general service times in two special cases: when the traffic load is sufficiently
high and when the request length is sufficiently small. Furthermore, using the branching process technique we derive exact
asymptotics of exponential type for the sojourn time in the M/M/1 queue. We obtain an equation for the asymptotic decay rate
and an exact expression for the asymptotic constant. The decay rate is studied in detail and is compared to other service
disciplines. Finally, using numerical methods, we investigate the accuracy of the exponential asymptote.
AMS 2000 Subject Classifications Primary:60K25,Secondary: 60F10,68M20,90B22 相似文献
104.
Ira S. Lurie 《Journal of chromatography. A》1997,780(1-2):265-284
The application of micellar electrokinetic capillary chromatography (MECC) to the analysis of illicit drug seizures is presented. Areas investigated include general screening and qualitative and, in some instances, quantitative analysis of various drugs, including heroin, opium, cocaine, amphetamines, LSD and anabolic steroids. Due to its high efficiency, high selectivity and general applicability, MECC is well suited for forensic drug analyses. 相似文献
105.
V. V. Sharutin I. V. Egorova T. V. Tsiplukhina A. V. Gerasimenko M. A. Pushilin 《Russian Journal of Coordination Chemistry》2004,30(12):884-887
Four new complexes of pentavalent bismuth are synthesized: Ph3Bi[OC6H2(Br3-2,4,6)]2, Ph3Bi[OC6H2(Cl3-2,4,6)]2, Ph4BiOC6H2(Br3-2,4,6), and Ph4BiOC6H2(Cl3-2,4,6). Tetraphenylbismuth aroxides are produced by the disproportionation reaction of ligands from pentaphenylbismuth and triphenylbismuth diaroxides in toluene or from pentaphenylbismuth and phenol. Triphenylbismuth diaroxides are synthesized from phenol, triphenylbismuth, and hydrogen peroxide taken at a molar ratio of 2 : 1 : 1, respectively, in diethyl ether. According to the X-ray diffraction data, the bismuth atom surrounding in 2,4,6-tribromophenoxytetraphenylbismuth has the configuration of a trigonal bipyramid with the aroxyl ligand in the axial position. The Bi-C and Bi-O bond lengths are 2,184, 2.190, 2.234, and 2.514 Å, respectively, and the equatorial CSbC angles are equal to 111.4°, 121.3°, and 121.3°.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 935–938.Original Russian Text Copyright © 2004 by Sharutin, Egorova, Tsiplukhina, Gerasimenko, Pushilin. 相似文献
106.
S. M. Arabei K. N. Solov'ev S. F. Shkirman G. D. Egorova 《Journal of Applied Spectroscopy》1990,52(4):381-386
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 52, No. 4, pp. 586–592, April, 1990. 相似文献
107.
Sharutin V. V. Egorova I. V. Tsiplukhina T. V. 《Russian Journal of General Chemistry》2004,74(2):310-310
Russian Journal of General Chemistry - 相似文献
108.
Sharutin V. V. Egorova I. V. Ivanenko T. K. Pavlushkina I. I. 《Russian Journal of General Chemistry》2002,72(12):1952-1952
Russian Journal of General Chemistry - 相似文献
109.
Sharutin V. V. Egorova I. V. Ivanenko T. K. Sharutina O. K. Gerasimenko A. V. 《Russian Journal of Coordination Chemistry》2003,29(4):297-299
Adduct of triphenylphosphine oxide and sulfuric acid was synthesized by reacting arenesulfonic acids with triphenylphosphine oxide (1 : 2) in the presence of the moisture of air. According to the X-ray diffraction data, the phosphorous atom has a distorted tetrahedral coordination. The sulfuric acid molecule is disordered over two sites and is linked with two triphenylphosphine oxide molecules through hydrogen bonds. 相似文献
110.
Ira B. Goldberg 《Magnetic resonance in chemistry : MRC》1973,5(1):29-31
The anion radical of 1,2-diphenylcyclobutene was studied by electron spin resonance. The hyperfine splittings were found to be 0·47 and 0·74 G for the meta-positions, 2·23 and 2·69 G for the ortho-positions and 4·21 G for the para-positions of the phenyl rings. The methylene proton splittings were 4·27 G, which would imply that the value of Q is 27 G, much lower than that of other cyclobutene anions. It was also estimated that the angle between the axis of the p-orbitals of the ethylene group and that of the phenyl group is about 30°, in agreement with that found for the tetraphenylethylene anion. 相似文献