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131.
132.
We present an algebra generated by a single pair of creation and annihilation operators b and b*. We prove that the algebra has a unique d-dimensional representation. Physically this algebra corresponds to a system where there are at most d − 1 particles in a state with otherwise same quantum numbers.  相似文献   
133.
The influence of pressure on the structure and protein-protein interaction potential of dense protein solutions was studied and analyzed using small-angle x-ray scattering in combination with a liquid state theoretical approach. The structural as well as the interaction parameters of dense lysozyme solutions are affected by pressure in a nonlinear way. The structural properties of water lead to a modification of the protein-protein interactions below 4?kbar, which might have significant consequences for the stability of proteins in extreme natural environments.  相似文献   
134.
We report the synthesis of layered [Zn(2)(bdc)(2)(H(2)O)(2)] and [Cu(2)(bdc)(2)(H(2)O)(2)] (bdc = benzdicarboxylate) metal-organic frameworks (MOF) carried out using the liquid-phase epitaxy approach employing self-assembled monolayer (SAM) modified Au-substrates. We obtain Cu and Zn MOF-2 structures, which have not yet been obtained using conventional, solvothermal synthesis methods. The 2D Cu(2+) dimer paddle wheel planes characteristic for the MOF are found to be strictly planar, with the planes oriented perpendicular to the substrate. Intercalation of an organic dye, DXP, leads to a reversible tilting of the planes, demonstrating the huge potential of these surface-anchored MOFs for the intercalation of large, planar molecules.  相似文献   
135.
The cyclotrimerization reaction of benzobarrelene derivatives was investigated. Dibromobenzobarrelene 10 was converted to the bromostannyl derivative 11 , which was used as the substrate of the cyclotrimerization reaction. Thus, reaction of 11 , with copper(I) thiophene‐2‐carboxylate (CuTC) gave a mixture of the isomeric cyclotrimers 5 and 6 and the dimers 12 and 13 , in addition to a trace of protodestannylated bromoalkene 14 (Scheme 2).  相似文献   
136.
The complexation of the crown ethers with Na+ ion was studied. 1H-NMR chemical shifts are discussed in terms of structural modification as well as also binding studies with UV–vis spectra were included. This revised version was published online in July 2005 with a corrected issue number. An erratum to this article is available at .  相似文献   
137.
Arif Da?tan  Metin Balci 《Tetrahedron》2005,61(23):5481-5488
The low and high temperature bromination reactions of bromobenzonorbornadiene derivatives were studied and the possible role of a neighboring group in rearrangements was investigated. New polybrominated benzonorbornadiene and benzonorbornene derivatives were synthesized. All compounds were characterized properly using NMR spectroscopy.  相似文献   
138.
139.
It is shown that a class of linearized solutions of the Poincaré gauge theory also solves the exact field equations of the same theory. Utilizing this property, some new solutions are given.Alexander von Humboldt Fellow.  相似文献   
140.
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