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51.
The molecular structure of triphenylamine was studied by gas-phase electron diffraction in combination with ab initio calculations. It is found that in the gas phase at 160°C the molecule possesses C3 symmetry. The principal geometric parameters are as follows (r a structure): N-C 1.421(4), C-Cmean 1.399(1), C-H 1.123(2) Å, bond angles NCC 123.6(10)° and 117.2(7)°, and CNC 119.9(2)°. Torsion angles around C-N bonds are ?39° and ?45°. Phenyl groups are rotated by 48° from the position in which the C3 axis lies in the phenyl ring plane.  相似文献   
52.
New complexes of Co(II), Ni(II), and Cu(II) with 1-(4-hydroxyphenyl)-1H-1,2,4-triazole (L) of the composition ML2(H2O)2(NO3)2 · nH2O (M = Co(II), n = 3; M = Ni(II), n = 0; M = Cu(II), n = 0) were synthesized and studied by photoelectron and IR spectroscopy, magnetochemistry, thermogravimetry, and X-ray powder diffraction analysis. The type of eff(T) relationship suggests that paramagnetic centers in the Co(II) chloride and Cu(II) nitrate and bromide complexes are involved in antiferromagnetic exchange interactions. The exchange energy values were estimated by the molecular field method.  相似文献   
53.
54.
The thermal effects of sodium glycylglycinate dissolution are determined calorimetrically at 298.15 K, and the enthalpies of glycylglycinate ion transfer from water to water-dimethyl sulfoxide solvent are calculated for compositions between 0.00 and 0.99 mole fractions of dimethyl sulfoxide. It is shown that when the concentration of the nonaqueous component is increased, the endothermicity of glycylglycinate ion transfer in the solution is considerably enhanced, weakening the solvation of anions.  相似文献   
55.
In this paper we consider asymptotic expansions for a class of sequences of symmetric functions of many variables. Applications to classical and free probability theory are discussed.  相似文献   
56.
Abstract

A new neutron spectrometer for investigations of elastic and inelastic neutron scattering on polycrystal microsamples under high pressure in diamond and sapphire anvils cells is described. The spectrometer is operating at the IBR-2 pulsed reactor at JINR. The time-of-flight method and ring-shaped multicounter detector are used to register the scattered neutrons. Parameters and methodical peculiarities of the device and the examples of experimental studies are given.  相似文献   
57.
Russian Journal of Physical Chemistry A - The effect vapors of the simplest cyclic hydrocarbons have on the structure of YBa2Cu3Oy (123) with high (у = 6.96) and low (у = 6.3) oxygen...  相似文献   
58.
Selyukov  R. V.  Naumov  V. V.  Vasilev  S. V. 《Technical Physics》2018,63(6):900-907
Technical Physics - Pt films with thickness h = 20–100 nm deposited on oxidized с-Si(100) substrate have been subjected to vacuum annealing at 500°C for 1 h, which resulted in...  相似文献   
59.
Abstract

A study of several factors has been carried out in order to determine their influence on rare earth phosphates precipitation from H3PO4 solutions obtained after the treatment of the Kola phosphate rock.  相似文献   
60.
Abstract

A suitable effective method of arwocompounds 2 synthesis through the alkoxyarsoranes I has been suggested. In dependence on the nature of substituents R and R arsazocompounds (as their phosphorus analogs) may exist in monomeric (2) and dimeric (3) forms, that has been confirmed by X-ray analysis.  相似文献   
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