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Simple Treatment (simple + treatment)
Selected AbstractsDefect-Related Optical Behavior in Surface Modified TiO2 NanostructuresADVANCED FUNCTIONAL MATERIALS, Issue 1 2005M. Prokes Abstract The surface modification of TiO2 nanostructures to incorporate nitrogen and form visible light absorbing titanium oxynitride centers is studied. Anatase TiO2 structures in the 5,20,nm range, formed by a wet chemical technique, were surface modified and the nitridation of the highly reactive TiO2 nanocolloid surface, as determined by X-ray photoelectron spectroscopy (XPS) studies, is achieved by a quick and simple treatment in alkyl ammonium compounds. The nitriding process was also simultaneously accompanied by metal seeding resulting in a metal coating layer on the TiO2 structures. The structure of the resultant titanium oxynitride nanostructures remains anatase. These freshly prepared samples exhibited a strong emission near 560,nm (2.21,eV), which red-shifted to 660,nm (1.88,eV) and dropped in intensity with aging in the atmosphere. This behavior was also evident in some of the combined nitrogen doped and metal seeded TiO2 nanocolloids. Electron spin resonance (ESR) performed on these samples identified a resonance at g,=,2.0035, which increased significantly with nitridation. The resonance is attributed to an oxygen hole center created near the surface of the nanocolloid, which correlates well with the observed optical activity. [source] An arbitrary Lagrangian,Eulerian finite element method for finite strain plasticityINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2003Francisco Armero Abstract This paper presents a new arbitrary Lagrangian,Eulerian (ALE) finite element formulation for finite strain plasticity in non-linear solid mechanics. We consider the models of finite strain plasticity defined by the multiplicative decomposition of the deformation gradient in an elastic and a plastic part (F = FeFp), with the stresses given by a hyperelastic relation. In contrast with more classical ALE approaches based on plastic models of the hypoelastic type, the ALE formulation presented herein considers the direct interpolation of the motion of the material with respect to the reference mesh together with the motion of the spatial mesh with respect to this same reference mesh. This aspect is shown to be crucial for a simple treatment of the advection of the plastic internal variables and dynamic variables. In fact, this advection is carried out exactly through a particle tracking in the reference mesh, a calculation that can be accomplished very efficiently with the use of the connectivity graph of the fixed reference mesh. A staggered scheme defined by three steps (the smoothing, the advection and the Lagrangian steps) leads to an efficient method for the solution of the resulting equations. We present several representative numerical simulations that illustrate the performance of the newly proposed methods. Both quasi-static and dynamic conditions are considered in these model examples. Copyright © 2003 John Wiley & Sons, Ltd. [source] Treatment of acquired syndactyly by gauze-fixed epidermal graft after radiosurgeryINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2003Seong Eon Kim MD Background, Acquired syndactyly is a rare disease that occurs mostly after disease, trauma, or other inflammatory conditions. It is usually treated by surgical incision with a flap or full-thickness skin graft, which is very invasive and requires hospitalization. Objective, The objective was to treat acquired syndactyly with an epidermal graft by suction blister after radiosurgery, because this procedure is much less invasive and can be performed in an outpatient base. Methods, A 65-year-old Korean woman had acquired syndactyly after various traditional treatments for tinea pedis. Five days after separation of syndactyly with radiosurgery, we prepared an epidermal sheet by suction blister, placed it on sterile meshed gauze, and applied it to the separated lesion. Results, The patient's lesion was completely healed after 7 days. Conclusion, Gauze-fixed epidermal graft after radiosurgery is a very effective and simple treatment for shallow acquired syndactyly. [source] Energy decomposition scheme for combined ab initio quantum mechanical / molecular mechanical methodsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 3 2005Imre Berente Abstract A new energy decomposition scheme is presented which paves the way toward the accurate and simple treatment of boundary atoms in combined ab initio quantum mechanical / molecular mechanical methods. We extend the wave function beyond the quantum region to a few atoms of the molecular mechanical region, which are linked directly to boundary atoms. Furthermore, we apply an approximate decomposition scheme, which allows calculating the total energy in terms of one-center atomic contributions. Comparisons with reference ab initio calculations are made, and good agreement is obtained for geometry parameters referring to CC, CC, and CX (XO, S, N) bonds at the boundary, as well as for the rotational energy curve of n -butane. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [source] An efficient and green synthesis of 3,3,-benzylidenebis (4-hydroxy-6-methylpyridin-2(1H)-one) derivatives through multi-component reaction in ionic liquidJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2008Daqing Shi A series of new 3,3,-benzylidenebis(4-hydroxy-6-methylpyridin-2(1H)-one) derivatives were synthesized via a three-component reaction of an aldehyde, an aniline or ammonium acetate and 6-methyl-4-hydroxypyran-2-one in ionic liquid. These heterocyclic compounds produced could be conveniently separated from the reaction mixture without any volatile organic solvents, and the ionic liquid could be readily reused without efficiency loss after simple treatment. [source] A simple treatment for gross haematuria caused by the ,nutcracker' phenomenonBJU INTERNATIONAL, Issue 7 2000G. Kawa No abstract is available for this article. [source] Highly Active and Removable Ruthenium Catalysts for Transition-Metal-Catalyzed Living Radical Polymerization: Design of Ligands and CocatalystsCHEMISTRY - AN ASIAN JOURNAL, Issue 8-9 2008Makoto Ouchi Dr. Abstract The systematic search and design of phosphine ligands (PR3) and amine cocatalysts resulted in obtaining pentamethyl-cyclopentadienyl (Cp*) ruthenium(II) phosphine complexes [RuCp*Cl(PR3)2], which are highly active and removable catalysts, for transition-metal-catalyzed living radical polymerization of methyl methacrylate (MMA). The catalysts are conveniently prepared in situ from a tetrameric precursor [RuCp*(,3 -Cl)]4 and a selected phosphine (PR3). The combination of the meta -tolyl phosphine [P(m -Tol)3] ligand and a primary diamine cocatalyst [NH2(CH2)6NH2] provides a highly active catalytic system with precision control of the molecular weight of the polymer. The high activity enables a low catalyst dose and a high turn-over frequency without deteriorating the controllability. A hydrophilic amine cocatalyst (amino alcohol) in place of the diamine, further forms an active and removable catalyst; simple treatment with acidic water gave colorless polymers visually free from metal residues (>97,% removal; <64,ppm). [source] | |||||||||||||