Materials Literature
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The pressure dependence of the structural phase transition temperature has been measured for the powder samples of NH4MgF3, NH4ZnF3, NH4MnF3, NH4CoF3, NH4CdF3, and NH4MnCl3 perovskites in the pressure range 0 to 600 MPa. It was found that the values of dT0/dP are negative for the Mg, Zn, Co, Mn trifluorides and positi…
The palladium(II) and platinum(II) complexes of 1,4-oxatellurane ( L ), having the composition [MCl 2 L 2 ], are synthesized and characterized spectroscopically and structurally (Pt complex only; Pt–Cl 2.3169(9) Å; Pt–Te 2.5945(3) Å) for the first time.
Tin oxide films were produced by chemical vapor deposition using monobutyltin trichloride and oxygen as reactants. The effect of H 2 O addition on deposition behavior and electrical properties at various deposition temperatures were investigated. The addition of H 2 O significantly increased deposition rates and lower…
The Neumann and Young equations for three-phase nematic contact lines have been derived using the momentum balance equation and classical liquid crystal physics theories. The novel finding is the presence of bending forces, originating from the anchoring energy of nematic interfaces, and acting on the contact line. Th…
Abstract The crystal structure of strontian potassicrichterite (Mg 4.871 Fe 0.126 3+ Mn 0.052 ) Σ5.049 (Na 1.425 Ca 0.348 Sr 0.297 ) σ2.07 K 0.873 Si 8.048 O 22 (OH) 2.15 – an unusual amphibole containing up to 3.7 wt.% SrO from the Murun alkaline massif, Eastern Siberia has been refined from X-ray powder diffraction…
A technique of hydrophobic surface design with a high degree of structural homogeneity has been developed for catalytic materials. Mesoporous activated carbons and silica gel were modified by (A) treatment with vinyltrimethoxysilane (vtms) or (B) chlorination with carbon tetrachloride followed by reaction with a Grign…
Abstract The Mössbauer and infrared spectra of Li- and Rb-saturated nontronites from Washington, USA (SWa-1), heat treated at different temperatures, were measured. The Mössbauer results show that diffusion of Li + into the 2:1 layer by heat treatment at 250-300°C does not affect the magnetic hyperfine interactions of…
A general method to describe the instrumental resolution function for grazing-angle X-ray scattering experiments is presented. A resolution function {\scr R} is introduced as the Gaussian joint-distribution function of the (interdependent) random deviation q ′ associated with the wavevector transfer q . Useful express…
We have grown clean N-salicylideneaniline (SA) single crystals large enough for optical measurements. The photochromism of a SA single crystal is investigated at different optical polarizations. Based on theoretical calculations, the structure configurations of the SA molecules in the colored keto form are analyzed. W…
The composition dependence of the optical phonon modes has been investigated in ABi2B2O9 (A = Ba, Ca, Sr; B = Nb, Ta) and Bi3BTiO9 (B =Nb, Ta). The lowest under-damped modes at 293 K generally soften upon heating, except BaBi2M2O9 (M = Nb, Ta) of which A sites of pseudo-perovskite layers are occupied by large Ba ions.…
This work reports the transport of carbon dioxide, oxygen, and nitrogen in amorphous membranes of vulcanized natural rubber reinforced with regenerated cellulose. The values of the permeability coefficient of carbon dioxide, oxygen, and nitrogen in the composites with 25% of cellulose, measured at 25 °C and 15 cmHg of…
Abstract Charge-transfer complexes of bis(methylthio)tetrathiafulvalene (DMT-TTF) bisannulated macrocycles with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) were prepared. The crystal structural analysis revealed an intramolecular dimer structure with the π-π overlap of DMT-TTF units. The magnitude o…
Several metal catalysts were examined for their effectiveness in activating hydrogen peroxide and oxygen as oxidants for conversion of lignin models to benzoquinones. Good yields of quinones were observed when certain heteropolymetallates were used as catalysts in the presence of hydrogen peroxide. Oxygen was generall…
Dielectric studies of a PbHfO3 (lead hafnate) single crystal undergoing two structural phase transformations at about 163°C (436 K) and 209°C (482 K) were performed in broad frequency and temperature range. Special attention was paid to the paraelectric phase. Investigations of the complex dielectric permittivity in t…
Dielectric properties of the AgNbO3 (AN) and Ag1−xLixNbO3 ceramics with x = 0.02, 0.04, 0.06 were investigated at microwaves (MW, 36 GHz) in the temperature range of 100 ÷ 570 K. including the phase transitions in AN at 340K (weak ferroelectric - antiferroelectric) and at 530K (antiferroelectric-antiferroelectric). Th…
Abstract 1H NMR spin-lattice relaxation times T1 and T1ρ as well as the electrical conductivity were measured as a function of temperature in (n-C5H11NH3)2ZnCl4 and (n-C12H25NH3)2ZnCl4. The highest-temperature solid phase in both compounds was found to be the rotator phase, where rod-like cations perform uniaxial reor…
With the advances made in the past decade, catalytic incineration of volatile organic compounds (VOCs) has become the technology of choice in a wide range of pollution abatement strategies. In this study, a test was undertaken for the catalytic incineration, over a chromium oxide (Cr2O3) catalyst, of n-hexane, benzene…
Galvanic action between zinc and steel is an important property that contributes to the high corrosion resistance of zinc-coated steels. Quantitative knowledge of the galvanic throwing power (i.e., the area of the steel surface that is not covered with zinc but is galvanically protected by the coating in the surroundi…
Measurements are reported for the d.c. Kerr response and the pretransitional behaviour of a new liquid crystal, 4-cyanophenyl 4-pentylbenzoate at and above the nematic-isotropic phase transition temperature. The real parts of the third order nonlinear susceptibilities chi(3) at and above the nematic-isotropic transiti…
In addition to the known sterols and ketosteroids beta-sitosterol (24 alpha-ethylcholest-5-en-3 beta-ol), stigmasterol (24 alpha-ethylcholesta-5,22-dien-3 beta-ol), campesterol (24 alpha-methylcholest-5-en-3 beta-ol), beta-sitostenone (stigmast-4-en-3-one, 24 alpha-ethylcholest-4-en-3-one), stigmastenone (stigmasta-4,…