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排序方式: 共有419条查询结果,搜索用时 31 毫秒
91.
92.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnett BA Bauer DA Bay A Bobbink GJ Buchanan CD Buijs A Caldwell DO Chao HY Chun SB Clark AR Cowan GD Crane DA Dahl OI Daoudi M Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Erné FC Fairfield KH Hauptman JM Hofmann W Hylen J Kamae T Kaye HS Kenney RW Khacheryan S Kofler RR Langeveld WG Layter JG Lin WT Linde FL Loken SC Lu A Lynch GR Madaras RJ Magnuson BD Masek GE Mathis LG Matthews JA Maxfield SJ Miller ES Moses W 《Physical review letters》1990,64(2):172-175
93.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson H Bintinger DL Bobbink GJ Bolognese TS Bross AD Buchanan CD Buijs A Caldwell DO Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Enomoto R Erné FC Fujii T Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG Linde FL Lindsey CS Loken SC Lu A Lu X 《Physical review letters》1986,57(25):3140-3143
94.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson H Bintinger DL Bobbink GJ Bolognese TS Bross AD Buchanan CD Buijs A Caldwell DO Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Enomoto R Erné FC Fujii T Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG Linde FL Lindsey CS Loken SC Lu A Lu XQ 《Physical review letters》1986,57(20):2500-2503
95.
Lou X van Buijtenen J Bastiaansen JJ de Waal BF Langeveld BM van Dongen JL 《Journal of mass spectrometry : JMS》2005,40(5):654-660
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was applied to the analysis of Ru(OCOCF(3))(2)(CO)(PPh(3))(2), Ru(OCOC(3)F(7))(2)(CO)(PPh(3))(2), Ir(tBuppy)(3) and Ir(ppy)(2)(acac) complexes. A troublesome problem in the MALDI-TOFMS characterization of these metal complexes is the possible replacement of complex ligands by matrix. In this contribution, 10 matrices, ranging from acidic to basic, were investigated: alpha-cyano-4-hydroxycinnamic acid (CHCA), 2,5-dihydroxybenzoic acid (DHB), sinapinic acid (SA), dithranol, 2,4,6-trihydroxyactophenone (THAP), 6-azo-2-thiothymine (ATT), norharman, 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene]malononitrile (DCTB), 4-nitroaniline (NA) and 2-amino-5-nitrophyridine (ANP). With most of the matrices, including the neutral and basic ones, matrix substitution of ligand could clearly be detected. Based on the experimental results, possible mechanisms of matrix substitution were discussed. It was demonstrated that the ligand exchange process might also occur through the gas-phase reactions initiated by laser shots. Among the matrices tested, DCTB was found to be the best one for the complexes that are prone to ligand exchange by matrix. 相似文献
96.
In this investigation, the structure, stability, and orientation of bovine serum albumin (BSA) adsorbed onto silica particles were studied using differential scanning calorimetry (DSC) and limited proteolysis in combination with mass spectrometry (MS). DSC gave information on the overall structural stability of BSA while limited proteolysis was used to probe the accessibility of enzymatic cleavage sites, thereby yielding information on the orientation and structure of BSA adsorbed to silica surfaces. Thermal investigation of BSA in various buffers, both free in solution and in the adsorbed state, showed that solutes that surround the protein played an important role with respect to the overall structural stability and the structural heterogeneity of BSA. Limited proteolysis with trypsin and chymotrypsin indicated that BSA in the adsorbed state is oriented with domain 2 facing the silica surface. Also, upon adsorption, no additional cleavage sites were exposed. The combination of the results presented in this study implied that BSA molecules adsorbed onto silica particles were significantly reduced in their structural stability, but not to an extent that internal residues within the native structure became fully exposed to the solution. 相似文献
97.
We introduce a simple semiempirical anharmonic Kirkwood-Keating potential to model A(x)B(1-x)C-type semiconductors. The potential consists of the Morse strain energy and Coulomb interaction terms. The optical constants of pure components, AB and BC, were employed to fit the potential parameters such as bond-stretching and -bending force constants, dimensionless anharmonicity parameter, and charges. We applied the potential to finite temperature molecular-dynamics simulations on Al(x)Ga(1-x)As for which there is no lattice mismatch. The results were compared with experimental data and those of harmonic Kirkwood-Keating model and of equation-of-motion molecular-dynamics technique. Since the Morse strain potential effectively describes finite temperature damping, we have been able to numerically reproduce experimentally obtained optical properties such as dielectric functions and reflectance. This potential model can be readily generalized for strained alloys. 相似文献
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100.
We describe the rational homotopy type of any component of the based mapping space map*(X,Y) as an explicit L ∞ algebra defined on the (desuspended and positive) derivations between Quillen models of X and Y. When considering the Lawrence–Sullivan model of the interval, we obtain an L ∞ model of the contractible path space of Y. We then relate this, in a geometrical and natural manner, to the L ∞ structure on the Fiorenza–Manetti mapping cone of any differential graded Lie algebra morphism, two in principal different algebraic objects in which Bernoulli numbers appear. 相似文献