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41.
42.
The excitation functions of elastic scattering at 180° for 16O + 40Ca and 12C + 40Ca are observed to oscillate between and 10?4 over a wide range of energies; the 16O + 58 Ni system shows a monotonic decrease to a value of over the energy range studied. 相似文献
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Bond PJ Cuthbertson JM Deol SS Sansom MS 《Journal of the American Chemical Society》2004,126(49):15948-15949
The in vitro study of membrane proteins for the purpose of physicochemical analysis or structure determination often relies upon successful reconstitution into detergent micelles. Moreover, a number of biological processes such as membrane protein folding and transport rely on lipid interactions which may resemble the micellar environment. Little is known about the structures of these micelles or the processes which lead to their formation. We therefore present two 50 ns all-atom molecular dynamics simulations of spontaneous dodecylphosphocholine micelle formation around representatives of the two major families of membrane proteins, a small beta-barrel protein, OmpA, and a model alpha-helical protein, glycophorin A. Despite differences in protein architecture, we highlight common mechanistic pathways in micelle formation, which are consistent with experimental studies. We characterize the exponential kinetics of detergent-protein adsorption and suggest a simple model which may explain the aggregation process. We also compare the results with 25 and 50 ns simulations of preformed micelles containing the same proteins. We confirm that the end structures of the self-assembled micelles are similar to those from their preformed counterparts, with each micelle presenting a bilayerlike environment to the enclosed protein. 相似文献
46.
Kieran AL Bond AD Belenguer AM Sanders JK 《Chemical communications (Cambridge, England)》2003,(21):2674-2675
Disulfide-linked cyclic porphyrin oligomers from dimer to tetramer can be selected and amplified virtually quantitatively from a dynamic combinatorial library using bis-thiol substituted zinc(II) porphyrin units with appropriate amine donor templates. 相似文献
47.
The crystal structure of 2,6-di(Pr(i))aniline hydrochloride contains hydrogen-bonded cubanes analogous to those in the complexes [M(2+)(2,6-di(Pr(i))C6H5N(2-))]4, M = Sn, Pb. 相似文献
48.
Bond AD Griffiths J Rawson JM Hulliger J 《Chemical communications (Cambridge, England)》2001,(23):2488-2489
Non-centrosymmetric structures are promoted through the use of perfluoroaromatics containing structure-directing CN...X (X = Br, I) supramolecular synthons. 相似文献
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The properties of passive Q-switched short-cavity dye lasers (SCDL) and passive Q-switched distributed-feedback dye lasers (DFDL) are investigated theoretically by using rate-equation models. The calculations, in agreement with experimental results, predict a significant decrease of the pulse energy fluctuation and the pulse duration of both the SCDL and DFDL, when passive Q-switching is used. 相似文献