Microscopic quantum hydrodynamics of systems of fermions: II

A closed system of nonstationary equations for a multielectron atom is constructed using a method previously developed for investigating multiparticle fermion systems. The well-known Thomas—Fermi—Dirac method is a particular case of the system. The exchange spin—spin correlations are calculated using an improved spin—spin interaction Hamiltonian. The dependence of the electron concentration on the self-consistent electric field potential and a discrete set of parameters determined by the total energy and the angular momentum of the atom is derived for stationary atom states.     

Stratification of a two-phase monodisperse system in a plane laminar flow

A thermodynamic approach is used to describe the distribution of particles of a disperse phase in a plane laminar flow. The effect of the density, shape, and velocity of disperse particles in the flow is considered. Conditions are described under which various modes of stratification of the flow (near-wall, central, intermediate, and multilayer modes) arise. The equilibrium distributions obtained are self-similar; this allows one to compare the behavior of colloidal, highly disperse, coarsely disperse, and coarse-grain systems for various shear velocities and flow widths.     

Synthesis of 3-(Dialkylamino)-4-halofuro[3,4-c]pyridin-1(3H)-ones

Russian Journal of Organic Chemistry - The reaction of 4-halo-3-hydroxyfuro[3,4-c]pyridin-1(3H)-ones with acyclic and alicyclic secondary amines in ethyl acetate afforded the corresponding...     

Heat-Resistant Epoxy Polymers of Anhydride Curing

The interaction of UP-643 epoxy-novolac resin with isomethyltetrahydrophthalic anhydride in the presence of the catalysts (azo-compounds of different structure) is studied. Latency of the catalysts is found. The possibility is shown of creating epoxy binders with a long lifetime (10–40 days) at room temperatures, cured at increased temperature up to heat-resistant polymers.     

Synthesis and some properties of heteronuclear platinum and palladium carbonyl clusters

Heteronuclear clusters of general formula [Pt_xPd_y(CO) _z] were synthesized by reaction of CO with PtCl₄ + PdCl₂ solutions in 95% ethanol at room temperature and atmospheric pressure. The products isolated were analyzed by IR spectroscopy, thermogravimetry, and X-ray powder diffraction.     

Uranyl cyanoacetate [UO<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>(NCCH<Subscript>2</Subscript>COO)<Subscript>2</Subscript>]: Synthesis,crystal structure,and absorption spectra

The U(VI) complex with cyanoacetic acid, [UO₂(H₂O)₂(NCCH₂COO)₂] (I), was synthesized from an aqueous solution, and its X-ray diffraction analysis was carried out. The crystals are orthorhombic: space group Pca2 ₁, a = 25.9605(7) Å, b = 6.7634(2) Å, c = 6.3398(2) Å, V = 1113.15(6) ų at 100 K, and Z = 4. The coordination polyhedron of the uranium atom is a distorted pentagonal bipyramid. The cations UO ₂ ²⁺ are bound into infinite zigzag chains by the bridging carboxyl groups of one of the anions of cyanoacetic acid. The carboxyl oxygen atom of the second anion, which is not involved in coordination, and the nitrogen atoms of the cyano groups form hydrogen bonds with the coordination water molecules. The layer structure of the compound is formed through the hydrogen bonds. The absorption spectra in the visible and infrared ranges of the crystalline compound are measured and analyzed.     

Crystal Structure of Sodium Perchloratotriacetatoneptunate(V) Monohydrate Na<Subscript>3</Subscript>NpO<Subscript>2</Subscript>(OOCCH<Subscript>3</Subscript>)<Subscript>3</Subscript>ClO<Subscript>4</Subscript> · H<Subscript>2</Subscript>O

The crystal structure of Na₃NpO₂(OOCCH₃)₃ClO₄ · H₂O was studied by single-crystal X-ray diffraction method. The structure is composed of the complex anions NpO₂(OOCCH₃)₃]²⁻, perchlorate anions, Na cations, and water molecules. The oxygen environment of Np(V) is a hexagonal bipyramid whose equatorial plane is formed by the oxygen atoms of three acetate ions. In addition to the acetate anions, the structure contains the perchlorate ion whose oxygen atoms, except for one, are included in the coordination environment of Na⁺ cations.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 8, 2005, pp. 636–640.Original Russian Text Copyright © 2005 by Charushnikova, Fedoseev, Starikova.     

Crystal Structure of Praseodymium(III) Complex [Pr(DMSO)8]2PMo10V2O40(NO3) · DMSO (DMSO = Dimethyl Sulfoxide)

Crystal structure of [Pr(DMSO)₈]₂PMo₁₀V₂O₄₀(NO₃) · DMSO (where DMSO is dimethyl sulfoxide) is determined by X-ray diffraction analysis. The Pr atom forms coordination polyhedron shaped like a distorted square antiprism with Pr–O distances varying from 2.432(6) to 2.476(6) Å. The oxygen atoms of a heteropolyanion are not involved in the coordination sphere of the Pr atom.     

New push–pull chromophores. Synthesis of 2-[4-Aryl-3-cyano-5-hydroxy-5-methyl-1<Emphasis Type="Italic">H</Emphasis>-pyrrol-2(5<Emphasis Type="Italic">H</Emphasis>)-ylidene]malononitriles

2-Aminoprop-1-ene-1,1,3-tricarbonitrile (malononitrile dimer) reacted with 1-arylpropane-1,2-diones in ethanol in the presence of piperidine to give new donor–acceptor chromophores, 2-[4-aryl-3-cyano-5-hydroxy-5-methyl-1H-pyrrole-2(5H)-ylidene]malononitriles.