Synthesis,structure and biological activity studies of 2‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]‐1‐aryl)‐3‐ferrocenyl prop‐2‐en‐1‐one derivatives

Fifteen new ferrocene derivatives containing 1H‐1,2,4‐triazole moiety were synthesized in various yields by the condensation of ferrocenecarboxaldehyde with 1‐aryl‐3‐(1H‐1,2,4‐triazo‐1‐yl)‐propen‐1‐ones in toluene. Their structures have been confirmed by ¹H NMR, IR, MS and elemental analysis. In addition, the crystal structure of 4l was determined. The antifungal and plant growth regulatory activities of the title compounds are discussed. Copyright © 2005 John Wiley & Sons, Ltd.     

Poly(arylene sulfide)s by nucleophilic aromatic substitution polymerization of 2,7‐difluorothianthrene

Poly(thianthrene phenylene sulfide) and poly(thianthrene sulfide) have been prepared by nucleophilic aromatic substitution polymerization of the activated monomer 2,7‐difluorothianthrene with bis thiophenoxide and sulfide nucleophiles, respectively. The resulting polymers are thermally stable, amorphous materials that have been characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), matrix‐assisted laser desorption/ionization‐time‐of‐flight (MALDI‐TOF) mass spectrometry, UV‐Vis spectroscopy, refractometry, and intrinsic viscosity (IV) measurements. The polymers produced exhibit 5% weight loss values approaching 500 °C in inert and air atmospheres and glass transition temperatures that range from 149 to 210 °C. Poly(thianthrene phenylene sulfide) with a number average molecular weight of 22,100 g/mol has been synthesized with an IV in DMPU of 0.62 dL/g at 30 °C. Creasable films of this polymer have been prepared by solvent casting and melt pressing at 250 °C. Films of poly(thianthrene phenylene sulfide) exhibit transparencies greater than 50% at wavelengths exceeding 400 nm and a high refractive index value of 1.692 at a wavelength of 633 nm, making the polymer interesting for optical applications. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2453–2461, 2009     

A comparative study of inflow conditions for two‐ and three‐dimensional spatially developing mixing layers using large eddy simulation

A series of spatially developing mixing layers are simulated using the large eddy simulation (LES) technique. A hyperbolic tangent function and data derived from boundary layer simulations are used to generate the inflow condition, and their effects on the flow are compared. The simulations are performed in both two and three dimensions. In two‐dimensional simulations, both types of inflow conditions produce a layer that grows through successive pairings of Kelvin–Helmholtz (K–H) vortices, but the composition ratio is lower for the hyperbolic tangent inflow simulations. The two‐dimensional simulations do not undergo a transition to turbulence. The three‐dimensional simulations produce a transition to turbulence, and coherent structures are found in the post‐transition region of the flow. The composition ratio of the three‐dimensional layers is reduced in comparison to the counterpart two‐dimensional runs. The mechanisms of growth are investigated in each type of simulation, and amalgamative pairing interactions are found in the pre‐transition region of the three‐dimensional simulations, and throughout the entire computational domain of those carried out in two‐dimensions. The structures beyond the post‐transition region of the three‐dimensional simulations appear to behave in a much different manner to their pre‐transition cousins, with no pairing‐type interactions observed in the turbulent flow. In order to accurately simulate spatially developing mixing layers, it is postulated that the inflow conditions must closely correspond to the conditions present in the reference experiment. Copyright © 2007 John Wiley & Sons, Ltd.     

Critical review of the molecular topology of semicrystalline polymers: The origin and assessment of intercrystalline tie molecules and chain entanglements

Intercrystalline molecular connections in semicrystalline polymers have been the subject of numerous discussions and controversies. Nevertheless, there is one point of agreement: such intercrystalline tie molecules have a prime role in the mechanical and use properties of the materials, notably the resistance to slow crack growth. This article is a critical review of the mechanisms of generation of the tie molecules during the stage of crystallization and of the experimental and theoretical assessment of their concentration. Polyethylene and related materials are mainly studied. The contribution of chain entanglements is also discussed in parallel with tie molecules. Particular attention is paid to Huang and Brown's statistical approach, which appears to be the most appropriate one for predictive purposes and has aroused much interest from various authors. Attempts are made to provide solutions to the shortcomings of this model. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1729–1748, 2005     

零级狄里克莱级数的增长性

首先研究了全平面上零级狄里克莱级数的系数和增长性之间的关系，然后证明了对于本级随机狄里克莱级数所确定的随机整函数，在每条水平直线上的增长性几乎必然（ａ．ｓ．）与相应的狄里克莱级数所确定的整函数的增长性相同．     

THE ZERO AND ORDER OF SOME SECOND ORDER LINEAR DIFFERENTIAL EQUATIONS WITH TRANSCENDENTAL MEROMORPHIC COEFFICIENTS

ＴＨＥＺＥＲＯＡＮＤＯＲＤＥＲＯＦＳＯＭＥＳＥＣＯＮＤＯＲＤＥＲＬＩＮＥＡＲＤＩＦＦＥＲＥＮＴＩＡＬＥＱＵＡＴＩＯＮＳＷＩＴＨＴＲＡＮＳＣＥＮＤＥＮＴＡＬＭＥＲＯＭＯＲＰＨＩＣＣＯＥＦＦＩＣＩＥＮＴＳＣＨＥＮＺＯＮＧＸＵＡＮＡｂｓｔｒａｃｔ：Ｉｎｔｈ...     

Luminescence properties of Tb and Eu-doped alumina films prepared by sol-gel method under various conditions and sensitized luminescence

Rare earth ion (Tb³⁺ and Eu³⁺)-doped alumina films were prepared by the aqueous sol-gel method under various conditions. The influences of the OH groups (phonon relaxation) and rare earth ion concentration (cross-relaxation) on luminescence were examined. In regard to the former relaxation, at treatment temperature above 600°C, reciprocal lifetime decreased with OH concentration, and below 500°C, decreased markedly and nonlinearly. On the other hand, in regard to the latter relaxation, there was negligible effect on luminescence for these doped films. The quantitative treatment was tried to lifetime considering these influences. Tb³⁺ and Eu³⁺ co-doped alumina films showed enhanced Eu³⁺ luminescence by the energy transfer from Tb³⁺ to Eu³⁺. Eu³⁺ luminescence intensity increased with a greater Tb³⁺ concentration.     

Die Beeinflussung des Kristallhabitus beim chemischen Transport

On the Influence of Chemical Transport on the Habit of Crystals The chemical transport of silicon with silicon tetrachloride as transporting agent leads to crystals with octahedral shape. On the other hand in the presence of adsorbable impurities the transported silicon crystallizes in the shape of long needles. Chemical transport reactions of tellurium are successful with iodine or sulphur. The presence of adsorbable transporting agents has considerable influence on the habit of crystals.     

Crystal Growth and Nonlinear Optical Properties of 4－Br－4＇－Methoxychalcone（BMC）

Ｃｒｙｓｔａｌ Ｇｒｏｗｔｈ ａｎｄ Ｎｏｎｌｉｎｅａｒ Ｏｐｔｉｃａｌ Ｐｒｏｐｅｒｔｉｅｓ ｏｆ ４－Ｂｒ－４＇－Ｍｅｔｈｏｘｙｃｈａｌｃｏｎｅ（ＢＭＣ）￥ＣＡＯＹａｎｇ；ＺＨＵＺｈｉｄｏｎｇ；ＳＨＥＮＸｉａｏｐｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＣ...     

Boundary Mobility and Energy Anisotropy Effects on Microstructural Evolution During Grain Growth

We have performed mesoscopic simulations of microstructural evolution during curvature driven grain growth in two-dimensions using anisotropic grain boundary properties obtained from atomistic simulations. Molecular dynamics simulations were employed to determine the energies and mobilities of grain boundaries as a function of boundary misorientation. The mesoscopic simulations were performed both with the Monte Carlo Potts model and the phase field model. The Monte Carlo Potts model and phase field model simulation predictions are in excellent agreement. While the atomistic simulations demonstrate strong anisotropies in both the boundary energy and mobility, both types of microstructural evolution simulations demonstrate that anisotropy in boundary mobility plays little role in the stochastic evolution of the microstructure (other than perhaps setting the overall rate of the evolution. On the other hand, anisotropy in the grain boundary energy strongly modifies both the topology of the polycrystalline microstructure the kinetic law that describes the temporal evolution of the mean grain size. The underlying reasons behind the strongly differing effects of the two types of anisotropy considered here can be understood based largely on geometric and topological arguments.