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divx (|?x u|p-2?xu)(x,y) + divy (|?y u|q-2?y u) (x, y) = ur(x, y){\rm div}_x (|\nabla_x u|^{p-2}\nabla_xu)(x,y) + {\rm div}_y (|\nabla_y u|^{q-2}\nabla_y u) (x, y) = u^r(x, y) 相似文献
137.
Reinaldo Rodriquez Ramos Jose A. Otero Hernandez Julian Bravo Castillero Federico J. Sabina 《Mechanics of Composite Materials》1996,32(3):286-291
The general expressions for the effective elastic, piezoelectric, and dielectric coefficients of a laminated piezocomposite composed of laminates in parallel connection are shown. By means of the asymptotic averaging method [12] these effective coefficients are calculated. The effective coefficients as well as physical properties such as electromechanical piezoelectric coupling coefficients, acoustic impedance, and wave velocity for a two-phase composite, where one phase is ceramic and the other one is polymer, are analyzed. A comparison with another results is shown.Presented at the Ninth International Conference on the Mechanics of Composite Materials, Riga, October, 1995.Published in Mekhanika Kompozitnykh Materialov, Vol. 32, No. 3, pp. 410–417, May–June, 1996. 相似文献
138.
Toniolo R Di Narda F Susmel S Martelli M Martelli L Bontempelli G 《Annali di chimica》2002,92(3):281-288
The quenching of superoxide ions, O2.-, by curcumin has been studied by electrogenerating this anion radical from oxygen dissolved in acetonitrile solvent (that is, at best, a mimic of the lipofilic layer of biological membranes), containing known amounts of curcumin. Voltammetric tests, combined with coulometric and spectrophotometric measurements, pointed out that each mol of curcumin is able to react with six mols of such anion radical, through a process initiated by an acid-base step, which provides the perhydroxyl radical, HO2.; that disproportionates rapidly to the anionic form of hydrogen peroxide, HO2-, and oxygen, which is thus partially regenerated. At the same time, curcumin is converted to the corresponding three-charged anion. The strict resemblance existing between the mechanism of the rapid superoxide radical decay caused by curcumin and that involved in the presence of the superoxodismutase enzyme (SOD) is also underlined. 相似文献
139.
Ataka K Giess F Knoll W Naumann R Haber-Pohlmeier S Richter B Heberle J 《Journal of the American Chemical Society》2004,126(49):16199-16206
A novel concept is introduced for the oriented incorporation of membrane proteins into solid supported lipid bilayers. Recombinant cytochrome c oxidase solubilized in detergent was immobilized on a chemically modified gold surface via the affinity of its histidine-tag to a nickel-chelating nitrilo-triacetic acid (NTA) surface. The oriented protein monolayer was reconstituted into the lipid environment by detergent substitution. The individual steps of the surface modification, including (1) chemical modification of the gold support, (2) adsorption of the protein, and (3) reconstitution of the lipid bilayer, were followed in situ by means of surface-enhanced infrared absorption spectroscopy (SEIRAS) and accompanied by normal-mode analysis. The high surface sensitivity of SEIRAS allows for the identification of each chemical reaction process within the monolayer at the molecular level. Finally, full functionality of the surface-tethered cytochrome c oxidase was demonstrated by cyclic voltammetry after binding of the natural electron donor cytochrome c. 相似文献
140.
Bhowon Minu G. Jhaumeer Laulloo Sabina Hosten Eric C. Elaheebacus Sumayya Dowlut Mounisha R. 《Transition Metal Chemistry》2021,46(7):537-545
The hexadentate N2S2O2 donor ligand N,N’-bis(3,5-tert-butylsalicylidene) diphenyl disulfide-2,2’-diamine was synthesised by the condensation of 2-aminophenyl disulfide and 3,5-di-tert-butyl-2-hydroxybenzaldehyde and its molecular structure was confirmed by X-ray studies. One of the tert-butyl groups in the Schiff base has rotational disorder around the C–C bond with ratio 0.56:0.44. The palladium complexes were prepared by the direct reaction of PdCl2(CH3CN)2 and Schiff base ligands N,N’-bis (5-tert-butylsalicylidene) diphenyl disulfide-2,2’-diamine and N,N’-bis(3,5-tert-butylsalicylidene) diphenyl disulfide-2,2’-diamine, respectively. The structure of the metal complexes was characterized by physico-chemical and spectroscopic methods. Palladium is in square-planar geometry bonded to imine nitrogen and phenolic O in both the complexes. The catalytic efficiency of the palladium complexes was evaluated in the cross-coupling reactions; Heck-Mizoroki reaction of iodobenzene and methyl acrylate and the Suzuki-Miyaura reaction of phenylboronic acid and iodobenzene, which gave low to moderate yields. Higher conversions were obtained for 2a as catalyst due to the increase in the number of bulky tertiary butyl groups in the structure. 相似文献 |