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931.
Supported, in part, by the Natural Sciences and Engineering Research Council of Canada 相似文献
932.
933.
Moro G Bonati L Bruschi M Cosentino U De Gioia L Fantucci PC Pandini A Papaleo E Pitea D Saracino GA Zampella G 《Theoretical chemistry accounts》2007,117(5-6):723-741
Computational approaches based on Molecular Dynamics simulations, Quantum Mechanical methods and 3D Quantitative Structure-Activity
Relationships were employed by computational chemistry groups at the University of Milano-Bicocca to study biological processes
at the molecular level. The paper reports the methodologies adopted and the results obtained on Aryl hydrocarbon Receptor
and homologous PAS proteins mechanisms, the properties of prion protein peptides, the reaction pathway of hydrogenase and
peroxidase enzymes and the defibrillogenic activity of tetracyclines. 相似文献
934.
935.
Alessandro Borghi Roberto Compagnoni Roberto Cossio Lorenzo Giuntini Mirko Massi Filippo Olmi Alba P. Santo Gloria Vaggelli 《Mikrochimica acta》2006,155(1-2):105-112
We present a multi-analytical and multi-instrumental approach to a petrologic study of garnets from metapelites characterized
by different metamorphic grades. The comparison between major, minor and trace element (Y) distribution in garnets crystallized
at different temperatures was performed by electron microprobe (EDS and WDS) and the Proton Induced X-ray Emission microprobe
(μ-PIXE).
Two garnet samples were selected from metapelite rocks at different metamorphic grades from the tectonic unit of Stilo, Calabrian–Peloritanian
Arc, Southern Italy. Quantitative spot analysis profiles and compositional X-ray maps of major elements and yttrium are reported.
The major element zoning of garnets is mostly characterized by a smoothed and gradual concentric variation of all elements
from core to rim. The Y concentration reveals a marked zoning with its distribution decreasing from about 7000 ppm to about
100 ppm from core to rim, respectively. The precise determination of the Y content by μ-PIXE technique allowed us to better
define the rock thermal history, by applying the Y geothermometer. In particular, a common starting temperature of about 450 °C
was calculated for the beginning of the garnet growth from all over the unit, but different temperatures in the range from
520 °C to 670 °C were estimated for the peak event in garnets from different areas, in agreement with the P–T values given
by the main rock mineral assemblages, reflecting a different metamorphic grade. 相似文献
936.
Painstaking spectrophotometric investigation was carried out on organo-metallic compounds to identify the most suitable compound for the detection of oxygen. A bis (histidinato) cobalt(II) solution was chosen, characterized by an absorption change at λ-408 nm as a function of the molecular oxygen concentration in the surrounding environment. An optical fiber system was developed that makes use of a halogen lamp as the source and an appropriate electronic circuit as a detection system. The optrode is a very small hollow fiber membrane filled with the solution and coupled with optical fibers. 相似文献
937.
In this short note we solve in the negative the three problems recently posed by Jie-Hua Mai and Wei-Hua Sun regarding the behaviour of almost periodic orbits and minimal sets of dynamical systems whose phase space is not regular. 相似文献
938.
Simone Fantauzzi Dr. Emma Gallo Prof. Alessandro Caselli Dr. Cristiana Piangiolino Dr. Fabio Ragaini Prof. Nazzareno Re Prof. Sergio Cenini Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(5):1241-1251
Herein we report the one-pot synthesis of several N-heterocyclic compounds by rearrangement reactions of N-aryl-2-vinylaziridines. The optimization of the synthetic methodology employed allowed us to obtain differently substituted 2,5-dihydro-1H-benzo[b]azepines in good yields and purities. The relationship between the nature of the starting N-aryl-2-vinylaziridine and the obtained N-heterocycle was also investigated. Finally, to rationalize all the experimental results reported in this paper a theoretical study was performed that casts light on the reaction mechanism. 相似文献
939.
Enzo Santaniello Silvana Casati Pierangela Ciuffreda Giuseppe Meroni Alessandro Pedretti Giulio Vistoli 《Tetrahedron: Asymmetry》2009,20(16):1833-1836
The Burkholderia cepacia lipase-catalyzed transesterification of 2-methyl-3-phenyl-1-propanol with vinyl esters proceeds with high enantioselectivity independently of the acyl chain length and the low enantioselectivity of the same reaction with 2-phenyl-1-propanol is not affected by chain length of the vinyl esters. A molecular modelling approach has been developed in order to rationalize the enzymatic results. 相似文献
940.
Alessandro Casoni Giuseppe Celentano Francesca Clerici Alessandro Contini Maria Luisa Gelmi Giuseppe Mazzeo Sara Pellegrino Carlo Rosini 《Tetrahedron: Asymmetry》2009,20(19):2247-2256
Herein we report a mild and efficient method to synthesize chiral 3-aminosubstituted isothiazole sulfoxides taking advantage of (+)- and (?)-((8,8-dichlorocamphoryl)sulfonyl)oxaziridine under microwave irradiation. The determination of the absolute configuration of the chiral sulfoxide was achieved by theoretical calculation of the CD spectra. The reason for the observed stereoselectivity was enlightened by means of analysis of our data using DFT calculations. 相似文献