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61.
S. V. Alekseenko P. A. Kuibin S. I. Shtork S. G. Skripkin M. A. Tsoy 《JETP Letters》2016,103(7):455-459
Processes of vortex reconnection on a helical vortex, which is formed in a swirling flow in a conical diffuser, have been studied experimentally. It has been shown that reconnection can result in the formation of both an isolated vortex ring and a vortex ring linked with the main helical vortex. A number of features of vortex reconnection, including the effects of asymmetry, generation of Kelvin waves, and formation of various bridges, have been described. 相似文献
62.
N. A. Bogachev D. A. Lyubichev G. L. Starova A. B. Nikolskii M. Yu. Skripkin 《Russian Journal of General Chemistry》2018,88(4):617-621
Solubility of copper(II) chloride at 25°C in binary organic solvents consisting of dimethyl sulfoxide, N,N-dimethylacetamide, and 1,4-dioxane was determined by the isothermal saturation method. The shape of solubility isotherms for all ternary systems under study is connected with the structural type of formed copper chloride solvates, the composition of which is defined by the solvent donor number. Solvates crystallize predominantly, where the metal ion coordinates molecules of the solvent with a greater donor power. The temperature increase in the system CuCl2–dimethylacetamide–dioxane up to 50°C leads to the formation of the cluster compound [Cu4Cl6O(DMA)4]; its structure was determined by the X-ray structural analysis method. 相似文献
63.
S. D. Isaev V. P. Sherstyuk U. F. Kozlov V. V. Skripkin I. Yanku 《Theoretical and Experimental Chemistry》1991,27(2):192-199
The spectral characteristics and photochemical transformations of adamantane-2-spiro-3-diazirine and its 5-hydroxy derivative were studied. The transformations of the photoexcited molecules of adamantane-2-spiro-3-diazirine in individual solvents and their mixtures and with various sources of UV radiation were studied by gas-liquid chromatography. The main process in saturated hydrocarbons is the formation of diazoadamantane, which is then converted into adamantanone azine. The addition of small amounts of formic or acetic acid leads to the formation of significant amounts of alkyladamantanes, which are the products from transformations of the intermediately formed carbene adamantylidene. Concurrent transformation paths are also observed in cyclohexene. It is suggested that the adamantylidene is preceded by the formation of an exciplex of diazirine with the polar solvent molecule. The ambiphilic nature of adamantylidene in the photolysis of diazirines was demonstrated by concurrent carbenylation.Kiev Polytechnical Institute, L. V. Pisarzhevskii Institute of Physical Chemistry, Academy of Sciences of the Ukrainian SSR, Kiev. Higher Chemical Technology School, Prague. Translated from Teoreticheskaya i Ésperimental'naya Khimiya, Vol. 27, No. 2, pp. 211–220, March–April, 1991. Original article submitted July 11, 1989. 相似文献
64.
Yu.V. Skripkin A.A. Pasynskii V.T. Kalinnikov M.A. Porai-Koshits L.Kh. Minacheva A.S. Antsyshkina V.N. Ostrikova 《Journal of organometallic chemistry》1982,231(3):205-217
The heteronuclear Cp2Nb(CO)(μ-CO)Mn(CO)4 (I), Cp2Nb(CO)(μ-H)Ni(CO)3 (II) and [Cp2Nb(CO)(μ-H)]2M(CO)4 (III, M = Mo;IV, M = W) complexes were prepared by reaction of Cp2NbBH4/Et3N with Mn2(CO)10 in refluxing toluene, direct reaction of Cp2NbBH4 with Ni(CO)4 in ether, and reaction of Cp2NbBH4/Et3N with M(CO)5. THF complexes (M = Mo or W) in THF/benzene mixture. An X-ray investigation of compounds I–III was performed. It is established that in I the bonding between Mn(CO)5 and Cp2Nb(CO) (with the angle (α) between the ring planes being 44.2(5)°) fragments takes place via a direct NbMn bond (3.176(1) Å) and a highly asymmetric carbonyl bridge (MnCco 1.837(5) Å, NbCco 2.781(5) Å). On the other hand, in complex II the sandwich Cp2Nb(CO)H molecule (angle α = 37.8°) is combined with the Ni(CO)3 group generally via a hydride bridge (NbH 1.83 Å, NiH 1.68 Å, NbHNi angle 132.7°) whereas the large Nb?Ni distance, 3.218(1) Å, shows the weakening or even absence of the direct NbNi bond. Similarly, in complex III two Cp2Nb(CO)H molecules (with α angles equal to 41.4 and 43.0°, respectively) are joined to the Mo(CO)4 group via the hydride bridges (NbH 1.83 and 1.75 Å and MoH 2.04 and 2.06 Å) producing a cis-form. The direct NbMo bonds are probably absent, since the Nb?Mo distances are rather long (3.579 and 3.565 Å). The effect of electronic and steric factors on the structure of heteronuclear niobocene carbonyl derivatives is discussed. 相似文献
65.
The solubility of d-metal halides in MCl2-M′Cl2-H2O systems with competitive complex formation at 25°C was discussed. The role of complex formation and hydration was traced.
As the stability constants become closer to each other, the salting-in regions in the crystallization braches of both chlorides
disappear.
Original Russian Text I.V. Zamyatin, M.Yu. Skripkin, 2007, published in Zhurnal Obshchei Khimii, 2007, Vol. 77, No. 2, pp.
252–259. 相似文献
66.
Maliarik M Nagle JK Ilyukhin A Murashova E Mink J Skripkin M Glaser J Kovacs M Horváth A 《Inorganic chemistry》2007,46(11):4642-4653
The new crystalline compounds Tl2Ni(CN)4 and Tl2Pd(CN)4 were synthesized by several procedures. The structures of the compounds were determined by single-crystal X-ray diffraction. The compounds are isostructural with the previously reported platinum analogue, Tl2Pt(CN)4. A new synthetic route to the latter compound is also suggested. In contrast to the usual infinite columnar stacking of [M(CN)4]2- ions with short intrachain M-M separations, characteristic of salts of tetracyanometalates of NiII, PdII, and PtII, the structure of the thallium compounds is noncolumnar with the two TlI ions occupying axial vertices of a distorted pseudo-octahedron of the transition metal, [MTl2C4]. The Tl-M distances in the compounds are 3.0560(6), 3.1733(7), and 3.140(1) A for NiII, PdII, and PtII, respectively. The short Tl-Ni distance in Tl2Ni(CN)4 is the first example of metal-metal bonding between these two metals. The strength of the metal-metal bonds in this series of compounds was assessed by means of vibrational spectroscopy. Rigorous calculations, performed on the molecules in D4h point group symmetry, provide force constants for the Tl-M stretching vibration constants of 146.2, 139.6, and 156.2 N/m for the NiII, PdII, and PtII compounds, respectively, showing the strongest metal-metal bonding in the case of the Tl-Pt compound. Amsterdam density-functional calculations for isolated Tl2M(CN)4 molecules give Tl-M geometry-optimized distances of 2.67, 2.80, and 2.84 A for M = NiII, PdII, and PtII, respectively. These distances are all substantially shorter than the experimental values, most likely because of intermolecular Tl-N interactions in the solid compounds. Time-dependent density-functional theory calculations reveal a low-energy, allowed transition in all three compounds that involves excitation from an a1g orbital of mixed Tl 6pz-M ndz2 character to an a2u orbital of dominant Tl 6pz character. 相似文献
67.
Skripkin M. Yu. Chernykh L. V. Pestova O. N. Baranauskaite V. E. Burkov K. A. Zamyatin I. V. Stepakova L. V. Gusev I. M. Gorbunov A. O. Bogachev N. A. Starova G. L. 《Russian Journal of General Chemistry》2019,89(6):1085-1101
Russian Journal of General Chemistry - The influence of ionic interactions in ternary aqueous and aqueous-organic solutions of metal halides on the structure of the solid phases in equilibrium with... 相似文献
68.
Bogachev N. A. Tsyrulnikov N. A. Starova G. L. Skripkin M. Yu. Nikolskii A. B. 《Russian Journal of General Chemistry》2017,87(11):2748-2749
Russian Journal of General Chemistry - It was proved by the IR spectroscopy that the first coordination sphere of nickel cations in the NiCl2·2DMSO·9H2O, NiCl2·5DMSO·4H2O, and... 相似文献
69.
L. V. Stepakova M. Yu. Skripkin L. V. Chernykh I. M. Gusev 《Russian Journal of General Chemistry》2006,76(4):512-516
The effect of the oxidation state of the metal on the solubility was analyzed using the example of CuClx-MCl-H2O (x = 1, 2; M = Li-Cs, NH4) ternary systems. The prevalence of acido complex formation is responsible for an essential similarity of the solubility isotherms: the presence of crystallization branches of complex salts and salting-in (or weak salting-out) of copper(I) and (II) chlorides, that increases in the order LiCl < NaCl < KCl < CsCl. The different stability of copper(I) and (II) chloride complexes results in that the chemical individuality of alkali metal cations is differently reflected in the shape of the solubility isotherms: The stronger complex formation in copper(I) systems results in leveling of this effect and the weaker complex formation with copper(II), in its differentiation. 相似文献
70.
Results of an experimental research of phase equilibrium in ternary systems MX2-NR4X-H2O [M = Cd(II), Cu(II), Co(II), Mg(II); X = Cl, Br; R = Me, Et, Bu] at 25°C were reported. A comparative analysis of compositions of solid compounds and regions of their crystallization, which are equilibrium with liquid phase, was conducted. An effect of hydration, association of salts of quaternary ammonium and acido complexation of ions of d-elements on the formation of the complex and double salts in the systems was presented. 相似文献