Acid-Base Properties and Structural Features of Composite Ion Exchangers Based on KU-23 and KM-2p Cation Exchangers and Hydrated Zirconium Oxide

A method for introduction of hydrated zirconium oxide into macroporous cation exchangers KU-23 and KM-2p and the acid-base properties and structural features of the composite ion exchangers are described.     

Heterylimidazoles

2-Aryl-4(5)-phenyl-5(4)-(N,N-dimethyl-5-benzimidazolonyl)imidazoles were obtained by condensation of 1-(N,N-dimethyl-5-benzimidazolonyl)-2-phenylglyoxal with aromatic aldehydes in acetic acid in the presence of ammonium acetate. It was shown that these compounds are either retarders or inhibitors of the radical polymerization of styrene.See [1] for communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 86–89, January, 1975.     

Dynamics of optically induced anisotropy in an ensemble of asymmetric top molecules in the gas phase

A complex theoretical and experimental investigation of the evolution of optically induced anisotropy in an ensemble of free asymmetric tops under collisionless conditions is performed. The dynamics of the orientational correlation functions is studied and the results of femtosecond measurements of the relaxation of the anisotropy of perylene fluorescence in the gas phase are reported. The results obtained are interpreted in terms of the theory developed. It is shown that, in contrast to steady-state anisotropy, the time kinetics of optically induced anisotropy yields more complete and typical data on the dynamics of vector correlations in an ensemble of molecules.     

Synthesis and structures of oligothioarylenecyclophosphonites

A new representative of phospho(scIII)crown ethers was obtained based on 4,4-thiodiphenol and tetraethyldiamide of phenylphosphonous acid. Thiaphospho(III)crown ethers can be prepared by different methods depending on the ratio of the initial reactants and the reaction conditions. The structures of the compounds obtained were confirmed by spectroscopic data and X-ray structural analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2313–2315, September, 1996.     

Powder diffraction study of the crystal structure oftrans-Pd(NH3)2Cl2

Trans-Pd NH₃)₂Cl₂ was studied by powder diffractometry. The unit cell parameters are a = 6.5408(8), b = 6.8573(8), c = 6.3574(6) Å, a = 103.303(5), Β = 102.457(3), γ = 100.612(4); V = 262.63 ų, Z = 2, space group $P\bar 1$ . The atomic coordinates were established from Patterson syntheses and refined by the Rietveld method: R_p = 10.7%, R_wp = 10.2%, R_exp = 5.6%, R_B = 3.6%. The crystal structure is of molecular type. The planar trans-Pd(NH₃)₂Cl₂ molecules are packed parallel to each other into columns along the z axis, with every next molecule rotated through an angle of ～ π/2. The observed packing of columns reproduces the cis-isomer quite closely. The structure has a disordering at 0.1Pd positions at 1/2, 0, 0 and 1/2 1/2, 0. A possible explanation for the nature of additional positions is offered.     

Kinetics of platinum(II) and platinum(IV) sorption from hydrochloric acid solutions with a complexing ion exchanger containing thiourea functional groups and with a strongly basic anion exchanger

The kinetics of platinum(II) and platinum(IV) sorption from 2 M HCl with Purolite S920 complexing ion exchanger containing thiourea functional groups and Purolite A500 strongly basic anion exchanger was studied in relation to the resin granule size, stirring intensity, and temperature.