Crystal and molecular structure of 2.2′-dihydroxyazobenzene

C₁₂H₁₀N₂O₂; monoclinic, space group P1 2₁/c 1 (Z = 2), 826 observed independent reflexions, R = 0.043; lattice dimensions at 25 °C, a = 975.8(3) pm, b = 466.8(1) pm, c = 1186.8(2) pm, β = 108.51(1)°.     

Chemistry of organic eutectics: Phenanthrene — benzoic acid and phenanthrene — cinnamic acid systems

Solid-liquid equilibrium data for binary systems of phenanthrene with benzoic acid and cinnamic acid, expressed in the form of temperature-composition curves, show the formation of a simple eutectic in each case. Linear velocity of crystallisation (v), studied by capillary method at different undercoolings (ΔT), suggests the applicability of Hillig-Turnbull equation, v = u(ΔT) ⁿ, where u and n are constants depending on the nature of solidification. Data on heats of fusion of pure components and eutectics, determined by the DTA method, infer appreciable interaction among the components in the eutectic melts. To highlight the nature of interactions among the components forming the eutectic melt, the excess thermodynamic functions such as h^E, s^E, and g^E were computed. Microscopic studies reveal that the structure of eutectic is different from those of the parent components. Infrared spectra, recorded in the region, 4000 —625 cm⁻¹, indicate weak interactions among the components in the eutectic.     

Dynamics of loop soliton solutions of $${\pmb {\mathcal {PT}}}$$PT-symmetric nonlocal short pulse equation

Nonlinear Dynamics - In this article, we present a system of coupled short pulse equations as integrability condition of associated generalized linear eigenvalue problem. We obtain system of...     

Charge Properties of Thorium Implanted in Silicon Oxide

Physics of Atomic Nuclei - A study of thorium atoms implanted in silicon oxide was carried out within the density functional theory method. The charge properties of Th in the ThO2:nSiO2 and...     

Thermally Stimulated Discharge Current Studies in Thin Films of Polyacrylamide

TSDC of pure polyacrylamide films of thickness 22 μ grown by isothermal solution growth technique has been studied as a function of polarizing field and polarizing temperature at a constant heating rate of 0.09 K s¹ In these studies only one TSDC peak was observed and the temperature corresponding to this peak was found to be independent of polarizing field strength but dependent on polarizing temperature. The activation energies, relaxation parameters and charge associated with the peak were evaluated. The origin of TSDC is discussed.     

Synthesis and Characterization of the Levyne-like Structure SAPO-35, Prepared with Cyclohexylamine as Templating Agent

The microporous aluminophosphate SAPO-35 with the levyne-like structure was prepared hitherto only with quinuclidine as templating agent. In this paper it is shown that also cyclohexylamine can be used for the synthesis of SAPO-35. The samples were characterized by X-ray diffraction, thermal analysis, adsorption isotherms, and micrographs. These investigations confirm the few data reported on SAPO-35 and give further informations. The number of acid sites (Brönstedt centres) was determined from the differential molar heat of chemisorption of NH₃ to three per unit cell.     

Investigation of the Interaction of Quartz with Hydrogen under Supply of Mechanical Energy (II) Investigation by IR Spectroscopy

Infrared investigations demonstrate a chemical interaction of quartz in hydrogen atmosphere during mechanical activation: By means of the SiH stretching band the number of formed SiH-groups is estimated as a function of the period of activation. of activation. This number is more than one order of magnitude less than the total number of adsorbed molecules.