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41.
Protein–protein conjugates formed by carbodiimide crosslinking reactions have been analyzed for the first time using CE. Lysozyme and BSA were chosen as model proteins to study the efficacy of N‐(3‐dimethylaminopropyl)‐N‐ethylcarbodiimide and N‐hydroxysuccinimide as crosslinkers. Detection of the molecular mass increase was checked by SDS‐PAGE. Commercially available, PVA‐coated capillaries showed appropriate selection, while phospho‐deactivated and dynamic PVA‐coated capillaries did not give suitable resolution. CE was found to be an efficient tool to characterize homo‐ (lysozyme–lysozyme) and hetero‐ (lysozyme–BSA) protein coupling by suitable variations of electrophoretic mobilities. 相似文献
42.
We consider optimal control problems of systems governed by stationary, incompressible generalized Navier–Stokes equations with shear dependent viscosity in a two-dimensional or three-dimensional domain. We study a general class of viscosity functions with shear-thinning and shear-thickening behavior. We prove an existence result for such class of optimal control problems. 相似文献
43.
Morphology of Imidazolium‐Based Ionic Liquids as Deposited by Vapor Deposition: Micro‐/Nanodroplets and Thin Films 下载免费PDF全文
Dr. José C. S. Costa Prof. Adélio Mendes Prof. Luís M. N. B. F. Santos 《Chemphyschem》2016,17(14):2123-2127
The morphology of micro‐ and nanodroplets and thin films of ionic liquids (ILs) prepared through physical vapor deposition is presented. The morphology of droplets deposited on indium‐tin‐oxide‐coated glass is presented for the extended 1‐alkyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ([CnC1im][Ntf2]; n=1–8) series, and the results show the nanostructuration of ILs. The use of in‐vacuum energetic particles enhances/increases the nanodroplets mobility/coalescence mechanisms and can be a pathway to the fabrication of thin IL films. 相似文献
44.
R. Ulbricht E. A. Grete V. Wartha Ad. Andrée C. Gänge L. Weigert B. Studer Jr. F. König B. Haas J. Nessler E. Geissler A. Béchamp Paul Müller Boussingault und K. Portele 《Fresenius' Journal of Analytical Chemistry》1881,20(1):457-462
Ohne Zusammenfassung 相似文献
45.
R.R. Adžić D.N. Simić A.R. Despić D.M. Dražić 《Journal of Electroanalytical Chemistry》1977,80(1):81-99
The catalytic effects of a submonolayer of lead on noble metals have been shown and discussed in terms of a previously published model. A theoretical analysis of these effects is presented. It was demonstrated that foreign metal monolayers allow a determination of the true catalytic activity of electrodes in the case of self-poisoning reactions. A volcano-shaped curve for oxidation of formic acid on noble metal electrodes was obtained. 相似文献
46.
Ad Cohen Geoffrey W. Coates Moshe Kol 《Journal of polymer science. Part A, Polymer chemistry》2013,51(3):593-600
The activities of C1‐symmetric dibenzyl zirconium complexes of Salan ligands that bear a halo‐substituted phenolate ring and an alkyl‐substituted phenolate ring in propylene polymerization with methylaluminoxane as cocatalyst were studied. These {ONNO′}ZrBn2‐type catalysts exhibited moderate‐to‐high activities and yielded polypropylene of low molecular weight. The degree of tacticity was found to depend on the steric bulk of the substituents on both phenolate rings and ranged from practically atactic to substantially isotactic (74–78% [mmmm] for polymerizations at room temperature by Lig5ZrBn2). Hemi‐isotactic polypropylene was not obtained, despite the diastereotopicity of the two positions. The pattern of stereo errors was consistent with the enantiomorphic site control of propylene insertion typically observed for C2‐symmetric catalysts and implied a facile site‐averaging mechanism. A regular 1,2‐insertion and a β‐H transfer to an incoming monomer correspond to the main propagation and termination processes, respectively. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
47.
Jaime Keller Robert M. Yamaleev Adán Rodríguez 《Advances in Applied Clifford Algebras》1998,8(2):235-254
We revise the mathematical formulation of the theory of a particle in a spherical surface, in particular we show that the
system of relations between two sets of generators of theSU(2) group lead to a formulation of nonrelativistic spinone half theory on the sphereS
3. First we examine various possibilities to extend this approach in the case of relativistic motion, then we give formulation
for the Dirac and Maxwell equations in homogeneous space-time where a geometrical point is associated with the notion of relativistic
top. Finally we formulate these equations in aS
3 surface embedded inR
5, using spherical system of coordinates, and examine the eigenvalue problem. 相似文献
48.
Jiří Adámek Horst Herrlich Jiří Rosický Walter Tholen 《Applied Categorical Structures》2002,10(3):237-249
Weak factorization systems, important in homotopy theory, are related to injective objects in comma-categories. Our main result is that full functors and topological functors form a weak factorization system in the category of small categories, and that this is not cofibrantly generated. We also present a weak factorization system on the category of posets which is not cofibrantly generated. No such weak factorization systems were known until recently. This answers an open problem posed by M. Hovey. 相似文献
49.
In Bell experiments, one problem is to achieve high enough photodetection to ensure that there is no possibility of describing the results via a local hidden-variable model. Using the Clauser-Horne inequality and a two-photon nonmaximally entangled state, a photodetection efficiency higher than 0.67 is necessary. Here we discuss atom-photon Bell experiments. We show that, assuming perfect detection efficiency of the atom, it is possible to perform a loophole-free atom-photon Bell experiment whenever the photodetection efficiency exceeds 0.50. 相似文献
50.
We have experimentally studied the distribution of the spatial extent of modes and the crossover from essentially single-mode to distinctly multimode behavior inside a porous gallium phosphide random laser. This system serves as a paragon for random lasers due to its exemplary high index contrast. In the multimode regime, we observed mode competition. We have measured the distribution of spectral mode spacings in our emission spectra and found level repulsion that is well described by the Gaussian orthogonal ensemble of random-matrix theory. 相似文献