The Crystal and Molecular Structure of Ethyl p-Chloro α-Cyano-β-Methyl-Cis-Cinnamate,C13H12No2Cl

Crystals of ethyl p-chloro α-cyano-β-methyl-cis-cinnamate, C₁₃H₁₂NO₂Cl, are orthorhombic, space group Pbcn, with eight molecules per unit cell, a = 17.31, b = 8.68 and c = 17.20 Å. The structure was solved by direct methods and refined subsequently by Fourier techniques. The benzene ring makes a dihedral angle of 60.0° with the ethylenic group. This suggests significant steric effects of the β-methyl group and of the carbonyl group on the orientation of the benzene ring. The conformation of the ethylene bond and the carbonyl group around the C_α? C bond is roughly cisoid and the angle of twist is 16.5°. Nearest-neighbour >C = C <groups make contact across a two-fold axis at a center-to-center distance of 4.33 Å.     

Oxidation kinetics for <Emphasis Type="Italic">cis</Emphasis>-9,<Emphasis Type="Italic">trans</Emphasis>-11 and <Emphasis Type="Italic">trans</Emphasis>-10,<Emphasis Type="Italic">cis</Emphasis>-12 isomers of CLA

The autoxidation processes of the cis-9,trans-11 (c9,t11) and trans-10,cis-12 (t10,c12) isomers of CLA were separately observed at ca. 0% RH and different temperatures. The t10,c12 CLA oxidized faster than the c9,t11 isomer at all tested temperatures. The first half of the oxidation process of t10,c12 CLA obeyed an autocatalytic-type rate expression, but the latter half followed first-order kinetics. On the other hand, the entire oxidation process of c9,t11 CLA could be expressed by the autocatalytic-type rate expression. The apparent activation energies and frequency factors for the autoxidation of the isomers were estimated from the rate constants obtained at various temperatures based on the Arrhenius equation. The apparent activation energies for the CLA isomers were greater than those for the nonconjugated n−6 and n−3 PUFA or their esters. However, the enthalpyentropy compensation held during the autoxidation of both the CLA and PUFA. This suggested that the autoxidation mechanisms for the CLA and PUFA were essentially the same.     

Preparation of Titanium Nitride Films from Amide Precursors Synthesized by Electrolysis

A TiN precursor solution was synthesized by galvanostatic electrolysis of Ti metal and isopropylamine at a current density of 50 mA·cm⁻² at room temperature. TiN films were prepared by dip-coating of the precursor solution on a Si wafer, followed by two-stage heat treatment at 400°C and a fixed temperature of 800–1200°C in flowing N₂, N₂/NH₃, or NH₃ gas. The TiN films were characterized by XRD, chemical analysis, XPS, and electrical resistivity measurements. The TiN films were composed of uniform grains 20 to 200 nm in size with thicknesses ranging from 300 to 400 nm at temperatures of 800–1200°C. The effect of the heat treatment atmosphere (N₂ and NH₃) on the impurity content, crystallinity, particle size, and electrical resistivity is discussed.     

Gelation of poly(vinyl alcohol)/phenol/water solutions and gel spinning

The light transmittance of the gels of poly(vinyl alcohol) (PVA)/phenol/water solutions was examined for the entire range of phenol/water content. Excellent transparency was found for the gels with phenol contents of 70–95 vol %. In full consideration of the results for the transparency and melting temperature of the gels and the viscosity and gelation ability of solutions, the PVA solutions of 75 vol % phenol content were selected for the gel spinning. The maximum dynamic moduli of drawn filaments at 25°C (room temperature) were 42 GPa (15x) for atactic PVA and 45 GPa (14x) for syndiotacticity-rich PVA. © 1995 John Wiley & Sons, Inc.     

New type of tin support for hydroprocessing catalyst

TiN supported molybdenum sulfide catalysts showed much higher activity for cleavage of C-C bonds than oxide supported molybdenum sulfide catalysts, indicating the possibility of a new generation of supports for hydroprocessing catalysts.     

Temperature Dependence of KIC for High-Pressure Hot-Pressed Si3N4 Without Additives

Temperature dependence of K_IC values for Si₃N₄ bodies sintered at high pressures without additives was studied from room temperature to 1400°C. Little change in K_K was found in this range.     

Effect of MgO Addition on the Bondability and Interfacial Reaction between Dielectric and Glass-Ceramics for the Fabrication of Multi-Component Ceramic Substrates

Bondability and interfacial reaction between dielectric and insulator layers have been examined to obtain a basic understanding of bonding mechanisms. Lead-containing complex perovskite was used as a dielectric material. Two kinds of glass-ceramics were used as insulator material; lead borosilicate glass containing Al_2O3 (insulator A) and the same containing Al₂O₃ and M_gO (insulator B). Dielectric and insulator layers did not bond when insulator A was used. When insulator B was used, however, strong bonding was achieved between the two layers by firing the powder compacts at temperatures between 800° and 1000°C. Addition of M_gO to lead borosilicate glass increased the thermal expansion coefficient to that of the dielectric and enhanced the formation of reaction layers, resulting in good bonding. Two reaction layers were identified. The main reaction products were enstatite and bredigite for one layer contacting the dielectric, and enstatite and a compound with the same diffraction pattern as that of faujasite for the other layers contacting insulator B.     

Influence of the nigrosine dye on the thermal behavior of polyamide 66

To reveal the effect of the nigrosine dye, that the addition of the dye lowers the crystallization point (T_c) of molten polyamide resins with substantially no shift in the melting point (T_m), thus suppressing the crystallization enhancement of the crystalline nucleation agents, the characteristics of polyamide 66 (PA‐66) containing nigrosine dye EX (N‐EX) were investigated. Differential scanning calorimetry (DSC) analysis showed that the addition of N‐EX reduced the crystallization rate and T_c of molten PA‐66 with substantially no shift in T_m, and the crystallization enthalpy per unit of weight of PA‐66 was substantially constant. T_c of molten PA‐66 was lowered with an increase in the amount of N‐EX and reached its maximum at 13 wt % N‐EX. Dynamic mechanical analysis showed that the glass‐transition temperature and the secondary glass‐transition temperature increased with an increasing amount of the dye. On the other hand, the DSC and X‐ray diffraction results indicated that no dye molecule was present in the crystal structure of PA‐66. This effect of the nigrosine dye on PA‐66 is in contrast to those of crystalline nucleation agents, plasticizers, and antiplasticizers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3270–3274, 2006     

Characterization and Sintering Behavior of Alkoxide-Derived Aluminosilicate Powders

Submicrometer SiO₂-Al₂O₃ powders with compositions of 46.5 to 76.6 wt% Al₂O₃ were prepared by hydrolysis of mixed alkoxides. Phase change, mullite composition, and particle size of powders with heating were analyzed by DTA, XRD, IR, BET, and TEM. As-produced amorphous powders partially transformed to mullite and Al-Si spinel at around 980°C. The compositions of mullite produced at 1400° and 1550°C were richer in Al₂O₃ than the compositions of stable mullite solid solutions predicted from the phase diagram of the SiO₂-Al₂O₃ system. Particle size decreased with increasing Al₂O₃ content. The sintered densities depended upon the amount of SiO₂-rich glassy phase formed during sintering and the green density expressed as a function of particle size.     

Effect of Nd2O3 Concentration on the Defect Structure of CeO2–Nd2O3 Solid Solution

An extensive X-ray study of CeO₂–Nd₂O₃ solid solutions was performed, and the densities of solid solutions containing various concentrations of NdO_1.5 were measured using several techniques. Solid solutions containing 0–80 mol% NdO_1.5 were synthesized by coprecipitation from Ce(NO₃)₃ and Nd(NO₃)₃ aqueous solutions, and the coprecipitated samples were sintered at 1400°C. A fluorite structure was observed for CeO₂–NdO_1.5 solid solutions with 0–40 mol% NdO_1.5, which changed to a rare earth C-type structure at 45–75 mol% NdO_1.5. The change in the lattice parameters of CeO₂–NdO_1.5 solid solutions, when plotted with respect to the NdO_1.5 concentration, showed that the lattice parameters followed Vegard's law in both the fluorite and rare earth C-type regions. The maximum solubility limit for NdO_1.5 in CeO₂ solid solution was approximately 75 mol%. The relationship between the density and the Nd concentration indicated that the defect structure followed the anion vacancy model over the entire range (0–70 mol% NdO_1.5) of solid solution.