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11.
V. I. Prosvirin 《Mechanics of Composite Materials》1972,8(1):168-169
The possibility of determining the parameters of a notch-type mechanical stress raiser which is equal in effectiveness to structural stress concentrators on the surface of flat glasses is indicated.Lenin Young Communist's League Institute of Civil Aviation Engineers, Riga. Translated from Mekhanika Polimerov, No. 1, pp. 181–182, January–February, 1972. 相似文献
12.
The effect of one-sided rapid cyclic heating on the deformation of rigidly clamped specimens of acrylic plastics has been investigated. It is shown that as the temperature drop increases, so does the bending deformation (concave toward the heated surface) of the unclamped specimens; the greatest temperature change during thermal cycling is concentrated in an active surface layer not more than 1.6 mm thick and is accompanied by the development of tensile stresses in that layer. The characteristics of the reversibility of the deformation upon subsequent annealing are examined.Riga Institute of Civil Aviation Engineers. Translated from Mekhanika Polimerov, No. 1, pp. 85–90, January–February, 1976. 相似文献
13.
Palii AV Ostrovsky SM Klokishner SI Reu OS Sun ZM Prosvirin AV Zhao HH Mao JG Dunbar KR 《The journal of physical chemistry. A》2006,110(51):14003-14012
The paper is aimed at the elucidation of the main factors responsible for the single-chain magnet behavior of the cobalt(II) disphosphonate compound Co(H2L)(H2O) with a 1D structure. The model takes into account the spin-orbit interaction, the axial component of the octahedral crystal field acting on the ground-state cubic 4T1 terms of the Co(II) ions, the antiferromagnetic exchange interaction between Co(II) ions as well as the difference in the crystallographic positions of these ions. The conditions that favor the single-chain magnet behavior based on spin canting in a 1D chain containing inequivalent Co(II) centers are discussed. The peculiarities of this behavior in chains containing orbitally degenerate ions are revealed. The qualitative explanation of the experimental data is given. 相似文献
14.
JETP Letters - Thin films of La-doped hafnium oxide synthesized by plasma-enhanced atomic layer deposition with subsequent rapid annealing have been studied. It has been found that the films under... 相似文献
15.
A new cobalt(II) carboxylate-phosphonate, namely, Co[HO2C(CH2)3NH(CH2PO3H)2]2, with a layered architecture has been synthesized by hydrothermal reactions. The Co(II) ion in the title compound is octahedrally coordinated by six phosphonate oxygen atoms from four carboxylate phosphonate ligands. Neighboring CoO6 octahedra are interconnected by phosphonate groups into a 2D layer with a 4,4-net topology. Adjacent layers are further cross-linked via hydrogen bonds between the noncoordinate carboxylate groups and noncoordinate phosphonate oxygens. The ac and dc magnetic susceptibility and magnetization measurements indicate that Co[HO2C(CH2) 3NH(CH2PO3H)2]2 is a canted antiferromagnet with T(c) = 8.75 K. 相似文献
16.
Schelter EJ Karadas F Avendano C Prosvirin AV Wernsdorfer W Dunbar KR 《Journal of the American Chemical Society》2007,129(26):8139-8149
A series of structurally related pseudocubic metal cyanide clusters of Re(II) and 3d metal ions [{MX}4{Re(triphos)(CN)3}4] (M = Mn, Fe, Co, Ni, Zn; X = Cl, I, -OCH3) have been prepared, and their magnetic and electrochemical properties have been probed to evaluate the effect of changing the identity of the 3d metal ion. Electrochemistry of the clusters reveals several rhenium-based oxidation and reduction processes, some of which result in cluster fragmentation. The richest electrochemistry was observed for the iron congener, which exists as the Re(I)/Fe(III) cluster at the resting potential and exhibits six clear one-electron reversible redox couples and two, closely spaced one-electron quasi-reversible processes. The [{MnIICl}4{ReII(triphos)(CN)3}4] complex exhibits single molecule magnetism with a fast tunneling relaxation process observed at H = 0 determined by micro-SQUID magnetization measurements. A comparative evaluation of the magnetic properties across the series reveals that the compounds exhibit antiferromagnetic coupling between the metal ions, except for [{NiIICl}4{ReII(triphos)(CN)3}4] that shows ferromagnetic behavior. Despite the large ground-state spin value of [{NiIICl}4{ReII(triphos)(CN)3}4] (S = 6), only manganese congeners exhibit SMM behavior to 1.8 K. 相似文献
17.
Wayne Ouellette Dr. Andrey V. Prosvirin Dr. Kelly Whitenack Kim R. Dunbar Prof. Jon Zubieta Prof. 《Angewandte Chemie (International ed. in English)》2009,48(12):2140-2143
Fixing a hole : Hydrothermal chemistry has been exploited in the preparation of a 3D framework material exhibiting 48 % accessible void volume and 1.5 % hydrogen uptake by weight at 120 kPa (see picture). The title compound also exhibits single‐chain magnetic behavior and reversible changes in magnetic properties upon solvation and desolvation.
18.
Feng ML Prosvirin AV Mao JG Dunbar KR 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(32):8312-8323
Six new divalent metal selenites have been synthesized by hydro-/solvothermal methods which leads to the incorporation of the organic template as a cation or a ligand. The structure of [H(2)pip][Cu(SeO(3))(2)] (1) (pip=piperazine) features 1D anionic chains of [Cu(SeO(3))(2)](2-) which are cross-linked by the template cations through hydrogen bonds into a 2D layer. In [Cu(C(3)H(4)N(2))(SeO(3))] (2) the organic template is coordinated to the copper(II) ion of the inorganic Cu(SeO(3)) layer. The isostructural compounds [H(2)en][M(HSeO(3))(2)Cl(2)] (en=ethylenediamine; M=Cu (3), Co (4)) contain layers of [MCl(2)(HSeO(3))(2)](2-) units (M=Cu, Co), which are cross-linked by the template cations via hydrogen bonds into a 3D network. The structure of [H(2)en][Cu(2)(SeO(3))(2)(HSeO(3))](2)H(2)O (5), consists of a pillared layered architecture in which the Cu(SeO(3)) layers are further interconnected by bridging hydrogen selenite groups (the pillar). The compound [H(2)pip][Cu(2)(Se(2)O(5))(3)] (6), which crystallizes as a 3D open framework represents the first organically templated metal diselenite. These new compounds are thermally stable up to at least 170 degrees C. All of the compounds exhibit fairly strong antiferromagnetic interactions. More interestingly, compounds 3 and 4 behave as a weak ferromagnets below the critical temperatures of T(c)=12 and 8 K, respectively, and both of them exhibit spin-flop phase transitions around 800+/-100 Oe. 相似文献
19.
V. A. Gritsenko T. V. Perevalov V. A. Volodin V. N. Kruchinin A. K. Gerasimova I. P. Prosvirin 《JETP Letters》2018,108(4):226-230
The atomic and electronic structures of metal-rich noncentrosymmetric zirconium oxide synthesized by the ion beam sputtering of a metallic target in an oxygen atmosphere has been studied by X-ray photoelectron spectroscopy, Raman scattering, spectral ellipsometry, and quantum-chemical simulation. It has been established that ZrOx < 2 consists of ZrO2, metallic Zr, and zirconium suboxides ZrOy. The stoichiometry parameter of ZrOy has been estimated. It has been shown that the optical properties of ZrOx < 2 are determined by metallic Zr. A model of fluctuation of the width of the band gap and a potential for electrons and holes in ZrOx < 2 based on spatial fluctuations of the chemical composition has been proposed. 相似文献
20.
The electronic structure of stoichiometric and oxygen-depleted Hf0.5Zr0.5O2 in the orthorhombic noncentrosymmetric phase has been studied by X-ray photoelectron spectroscopy and quantum-chemical simulation based on the density functional theory. It has been established that the ion-etching-induced peak in the photoelectron emission spectrum with the energy above the top of the o-Hf0.5Zr0.5O2 valence band is due to oxygen vacancies. A method of estimating the density of oxygen vacancies from the comparison of the experimental and theoretical photoelectron spectra of the valence band has been proposed. It has been established that oxygen polyvacancies in o-Hf0.5Zr0.5O2 are not formed: the energetically favorable spatial arrangement of oxygen vacancies in a crystal corresponds to noninteracting oxygen vacancies distant from each other. 相似文献