New uranyl complex with imidazolidine-2-one [UO<Subscript>2</Subscript>(Imon)<Subscript>4</Subscript>(H<Subscript>2</Subscript>O)](ClO<Subscript>4</Subscript>)<Subscript>2</Subscript>: Structure and some properties

A complex of uranyl perchlorate with imidazolidine-2-one as the molecular ligand, [UO₂(Imon)₄(H₂O)](ClO₄)₂ (I), was synthesized and structurally characterized by X-ray diffraction analysis. The coordination number of the uranium atom is 7. The nearest environment of the uranyl ion includes four O atoms of the imidazolidine-2-one molecules and one O atom of the water molecule. The perchlorate anions are outer-sphere ligands. The crystals are monoclinic: space group P2₁/c; a = 16.294(3) Å, b = 16.135(3) Å, c = 9.987(2) Å, = 97.69 (3)°, V = 2603.0 (9) ų, (calcd) = 2.117 g/cm³, Z = 4. The IR and luminescence spectra of the complex were recorded.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 919–924.Original Russian Text Copyright © 2004 by Andreev, Antipin, Budantseva, Tuchina, Serezhkina, Fedoseev, Yusov.     

Conversion of Heterocycles of The Dihydrothiazine–Thiazoline Series in Aqueous Solutions

When heterocycles of the dihydrothiazine–thiazoline series are treated with an aqueous solution of base, they undergo ring opening, leading to formation of ureidoalkanethiols. Study of solvolysis of the heterocycles when treated with ammonia permitted us to observe a novel heterocyclic ring opening reaction, occurring with formation of 2(3)-guanidinoalkanethiols. We have developed a novel preparative method for obtaining 2(3)-guanidinoalkanethiols.     

Model of the crystal structure of Np(VI) sulfate with dimethyl sulfoxide, NpO2SO4 ⋅ 2SO(CH3)2 ⋅ H2O

A new complex compound, neptunium(VI) sulfate, was grown from aqueous solutions and studied by the methods of X-ray structure analysis. The model of the crystal structure was determined by direct methods within the sp. gr. P2₁ and was refined in the anisotropic approximation (R = 6.2%, 1044 independent reflections). The structure is built by tetragonal and hexagonal Np bipyramids. A hexagonal bipyramid can be considered as a polyhedron derived from a pentagonal bipyramid, in which one equatorial O atom is replaced by two atoms located above and below the equatorial plane. The polyhedra are linked in chains through S-tetrahedra. The chains are linked into a three-dimensional framework by hydrogen bonds with the participation of DMSO groups.     

On the Relationship of the Fractal Dimension of Structure with the State of Drying Drops of Crystallizing Solutions (Thermodynamic and Experimental Modeling)

Crystallography Reports - The processes occurring in aqueous salt solutions have been investigated based on thermodynamic and experimental modeling. The self-organization in a drying drop of...     

Ejection of Particles from the Free Surface of Shock-Loaded Lead into Vacuum and Gas Medium

The presence and behavior of a gas–metal interfacial layer at the free surface of shock-wave driven flying vehicles in gases of various compositions and densities has not been sufficiently studied so far. We present new comparative data on “dusting” from the free surface of lead into vacuum and gas as dependent on the surface roughness, pressure amplitude at the shock-wave front, and phase state of the material. Methods of estimating the mass flux of ejected particles in the presence of a gas medium at the free metal surface are proposed.     

Spiro heterocyclization of 4-aryl-4-oxobutane-1,1,2,2-tetracarbonitriles to 3H-pyrrole derivatives, 2-oxa-7-azaspiro[4.4]nona-3,6,8-trienes

4-Aryl-3-methyl-4-oxobutane-1,1,2,2-tetracarbonitriles reacted with morpholine to give 8-amino-3-aryl-1-imino-4-methyl-6-(morpholin-4-yl)-2-oxa-7-azaspiro[4.4]nona-3,6,8-triene-9-carbonitriles.     

Improving the Efficiency of Single-Sideband Millimeter-Wave Reception by Returning the Signal Converted into Image

We describe the technique, apparatus, and the results of studies of the possibility of millimeter-wave single-sideband reception with minimum loss, associated with conversion into image. The single-sideband noise temperature of the receivers is improved by a factor of 1.4-1.9 in the N and Y bands.     

Growth and properties of diamond-like films deposited from cyclohexane-argon mixtures in low-temperature plasma

The deposition of diamond-like films on polymer substrates from low-temperature cyclohexane-argon plasma was studied. The deposition rate was found to be proportional to the mass flow rate of cyclohexane vapor and independent of the mass flow rate of argon. The microhardness of the films and the light absorption coefficient in the blue spectral region depend on the ratio between the deposition rate and ion current density.Deceased in 1996.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2419–2421, October, 1996.