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排序方式: 共有393条查询结果,搜索用时 145 毫秒
91.
Olive Recombinant Hydroperoxide Lyase,an Efficient Biocatalyst for Synthesis of Green Leaf Volatiles
92.
The following are notes on the geometry of the bidisk, H 2 × H 2. In particular, we examine the properties of equidistant surfaces in the bidisk. 相似文献
93.
Virginie Breau James A. Ibers 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):584-586
The title compounds, bis(diethoxyselenophosphinoyl) triselenide, [P(OEt)2Se]Se3[P(OEt)2Se], and bis(diisopropoxyselenophosphinoyl) diselenide, [P(OiPr)2Se]Se2[P(OiPr)2Se], comprise an Se3 chain or an Se2 chain bridging two (RO)2PSe groups. 相似文献
94.
Virginie Konlack Socgnia Olivier Menoukeu-Pamen 《Journal of Mathematical Analysis and Applications》2015
In the present work, a stochastic maximum principle for discounted control of a certain class of degenerate diffusion processes with global Lipschitz coefficient is investigated. The value function is given by a discounted performance functional, leading to a stochastic maximum principle of semi-couple forward–backward stochastic differential equation with non-smooth coefficients. The proof is based on the approximation of the Lipschitz coefficients by smooth ones and the approximation of the infinite horizon adjoint process. 相似文献
95.
Blanc R Héran V Rahmani R Commeiras L Parrain JL 《Organic & biomolecular chemistry》2010,8(24):5490-5494
An efficient synthesis of deoxy-lambertellols was reported through a highly chemo- and diastereoselective intermolecular Diels-Alder cycloaddition between trans-1,2-disiloxybenzocyclobutenes and 2-methylprotoanemonine. Such transformation with δ-substituted γ-alkylidenebutenolides, to prepare new analogues of these tricyclic spirolactones, which would be very difficult to prepare by other ways, was also studied. 相似文献
96.
Taton D Baussard JF Dupayage L Poly J Gnanou Y Ponsinet V Destarac M Mignaud C Pitois C 《Chemical communications (Cambridge, England)》2006,(18):1953-1955
Branched water-soluble copolymers were obtained by direct radical crosslinking copolymerisation of acrylic acid or acrylamide and N,N'-methylenebisacrylamide at high solid content in the presence of an O-ethylxanthate as a reversible chain transfer agent. 相似文献
97.
Virginie Daru Marie-Christine Duluc Olivier Le Maître Damir Juric Patrick Le Quéré 《Comptes Rendus Mecanique》2006,334(1):25-33
A model for the simulation of boiling flow with phase change in a closed cavity is presented. A front-tracking method is used to deal with the liquid–vapor interface. The liquid phase is incompressible while the vapor phase is weakly compressible and obeys to the perfect gas law. This model can deal with large density ratio () flows while accounting for the saturation curve. Computations are performed on a 1D validation case, idealizing a pressure cooker. Results are compared with a low Mach number approximation. To cite this article: V. Daru et al., C. R. Mecanique 334 (2006). 相似文献
98.
Competitive adsorption on adsorptive solid-phase microextraction (SPME) fibres implies careful determination of operating
conditions for reliable quantitative analysis of VOCs in indoor air. With this objective, two analytical approaches, involving
non-equilibrium and equilibrium extraction, were compared. The average detection limit obtained for GC-MS analysis of nine
VOCs by the equilibrium method is 0.2 μg m−3, compared with 1.9 μg m−3 with the non-equilibrium method. The effect of the relative humidity of the air on the calibration plots was studied, and
shown to affect acetone adsorption only. Hence, the concentrations that can be accurately determined are up to 9 μmol m−3. The methods were then applied to indoor air containing different concentrations of VOCs. The non-equilibrium method, involving
short extraction time, can be used for detection of pollution peaks whereas equilibrium extraction is preferable for measurement
of sub-μg m−3 ground concentration levels.
相似文献
99.
100.
Sébastien Prévost Sébastien Gauthier Maria Cristina Caño de Andrade Céline Mordant Ali Rhida Touati Philippe Lesot Philippe Savignac Tahar Ayad Phannarath Phansavath Virginie Ratovelomanana-Vidal Jean-Pierre Genêt 《Tetrahedron: Asymmetry》2010,21(11-12):1436-1446
The dynamic kinetic resolution (DKR) of racemic α-chloro β-ketoesters and α-chloro β-ketophosphonates through ruthenium-mediated asymmetric hydrogenation is reported. The corresponding α-chloro β-hydroxyesters and α-chloro β-hydroxyphosphonates were obtained in good to high enantio- and diastereomeric excesses using, in particular, the atropisomeric ligand DIFLUORPHOS. This methodology allowed an efficient preparation of the anti phenylisoserine side chain of Taxotere® which has been used for the hemisynthesis of the cancer therapeutic agent itself. In addition, 13C NMR in chiral oriented solvents was used to investigate the DKR effect. 相似文献