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991.
Prof. Dr. Norberto Garcia‐Cairasco Prof. Dr. Miguel Moyses‐Neto Flavio Del Vecchio José A. C. Oliveira Francisco L. dos Santos Dr. Olagide W. Castro Dr. Gabriel M. Arisi Prof. Dr. Márcio Dantas Dr. Ruither O. G. Carolino Prof. Dr. Joaquim Coutinho‐Netto Dr. Andre L. A. Dagostin Dr. Marcelo C. A. Rodrigues Prof. Dr. Ricardo M. Leão Dr. Samir A. P. Quintiliano Prof. Dr. Luiz F. Silva Jr. Prof. Dr. Leonardo Gobbo‐Neto Prof. Dr. Norberto P. Lopes 《Angewandte Chemie (International ed. in English)》2013,52(49):13067-13070
992.
993.
G. Calvarin G. Clech J.F. Berar D. Andre 《Journal of Physics and Chemistry of Solids》1982,43(9):785-790
X-Ray analysis of the metastable triclinic phase of ferrocene has been carried out at 130 K, from a single crystal cooled through the transition temperature (164 K). The molecular packing is close to a face centred one; however the numerous reflections breaking this symmetry give evidence for a P1 or P1̄ superstructure which appears to be disordered. Calculations of lattice energy performed at 130 K and 15 K show that the triclinic phase of ferrocene has two possible molecular packings, quite energetically similar, of face-centred or P1̄ symmetry. Thus, when the triclinic phase is obtained by cooling a crystal from room temperature, its structure is constituted by a mixture of both packings whose ratio depends on the thermal history. On the other hand, the molecular coordinates and the configuration of ferrocene (D5h) in the stable ordered orthorhombic phase have been determined by minimizing the lattice energy. The mechanism of the order-disorder phase transition at 250 K (orthorhombic monoclinic), as also the existence below 164 K of another ordered packing, the triclinic one, are discussed in terms of ring libration. 相似文献
994.
Balawant S. Joshi Venkatesh N. Kamat S. William Pelletier Kuantee Go Krishna Bhandary 《Tetrahedron letters》1985,26(10):1273-1276
The structure of ailanthot (1), having the triterpene skeleton (20)-4 4,8 β - trimethyl-14, 18-cyclo 5a, 13a, 14a, 17a-cholestane, has been assigned by spectral analysis and X-ray crystal structure determination. 相似文献
995.
Dynamic and thermal results for developing laminar pulsed flows in a duct are presented. They have been investigated by means of a finite difference model. This flow is described in terms of an unsteady pulsed flow superimposed on a steady incompressible one with the following main assumptions: a sinusoidal modulation for the pulsation and a uniform wall temperature. Results emphasize the importance of this entry region, where four simultaneous developments occur: steady—dynamic and thermal—and unsteady—dynamic and thermal. 相似文献
996.
997.
Philippe Bernard Dmitri B. Kireev Jacques R. Chrétien Pierre-Louis Fortier Lucien Coppet 《Journal of computer-aided molecular design》1999,13(4):355-371
Automated docking and three-dimensional Quantitative Structure-Activity Relationship studies (3D QSAR) were performed for a series of 82 reversible, competitive and selective acetylcholinesterase (AChE) inhibitors. The suggested automated docking technique, making use of constraints taken from experimental crystallographic data, allowed to dock all the 82 substituted N-benzylpiperidines to the crystal structure of mouse AChE, because of short computational times. A 3D QSAR model was then established using the CoMFA method. In contrast to conventional CoMFA studies, the compounds were not fitted to a reference molecule but taken in their 'natural' alignment obtained by the docking study. The established and validated CoMFA model was then applied to another series of 29 N-benzylpiperidine derivatives whose AChE inhibitory activity data were measured under different experimental conditions. A good correlation between predicted and experimental activity data shows that the model can be extended to AChE inhibitory activity data measured on another acetylcholinesterase and/or at different incubation times and pH level. 相似文献
998.
S. Andre F. Guida‐Pietrasanta A. Rousseau B. Boutevin G. Caporiccio 《Journal of polymer science. Part A, Polymer chemistry》2002,40(24):4485-4492
The synthesis of new α,ω‐dihydrosilane hybrid fluorinated polysiloxanes is described via the polycondensation between a diallyl perfluorinated compound and tetramethyldisiloxane. Control over the size of the oligomers is possible when the reaction is performed in two steps. The length of the polysiloxane chains influences the glass‐transition temperature and the thermal stability of the fluorinated oligomers: the higher the length is, the higher the glass‐transition temperature and the thermal stability are. The synthesized compounds have been characterized with 1H, 19F, and 29Si NMR spectroscopy. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4485–4492, 2002 相似文献
999.
We describe the use of “capto-dative” olefins as novel ketene equivalents which behave as efficient dienophiles in the Diels-Alder process. 相似文献
1000.
A large body of evidence has shown that exposure to ambient particulate matter (PM) leads to asthma exacerbation through an excitation of allergic inflammation. Utilizing diesel exhaust particles (DEPs) as a model air pollutant, we and others have demonstrated that PM contains redox-active chemicals that generate inflammation through an oxidative stress mechanism. Recently, the strengths of proteomics have enabled us to demonstrate that organic DEP extracts induce a hierarchical expression pattern of oxidative stress-induced proteins in macrophages and epithelial cells. As a further extension of this work, we now employ a new phosphosensor fluorescent dye, Pro-Q Diamond, to elucidate the induction of phosphoproteins and intracellular signaling cascades that may play a role in DEP-induced inflammation. We demonstrate that DEPs induced the phosphorylation of several phosphoproteins that belong to a number of signaling pathways as well as other oxidative stress pathways. In combination with cytokine array, phosphoproteome analysis using Pro-Q Diamond allowed us to characterize the aromatic and polar chemicals of DEPs that are involved in the activation of three different mitogen-activated protein (MAP) kinase signaling pathways. 相似文献