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排序方式: 共有701条查询结果,搜索用时 31 毫秒
31.
Jacqueline Destain Patrick Fickers Frédéric Weekers Benoît Moreau Philippe Thonart 《Applied biochemistry and biotechnology》2005,121(1-3):269-277
In this article, we report the development and optimization of an industrial culture medium for the production of extracellular
lipase in the yeast Yarrowia lipolytica. Until now olive oil in combination with glucose was used as the carbon source and inducer for the production of lipase.
Our results demonstrate that methyloleate, a cheap hydrophobic compound, could efficiently substitute olive oil as the inducer
and carbon source for lipase production. A new process of lipase production was developed yielding a twofold increase in the
level of production compared with the levels in previous reports. 相似文献
32.
Dr. Renata Avena Maia Felipe Lopes Oliveira Prof. Vincent Ritleng Prof. Qiang Wang Dr. Benoît Louis Prof. Pierre Mothé Esteves 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(30):8048-8055
Covalent organic frameworks (COFs) RIO-13, RIO-12, RIO-11, and RIO-11m were investigated towards their CO2 capture properties by thermogravimetric analysis at 1 atm and 40 °C. These microporous COFs bear in common the azine backbone composed of hydroxy-benzene moieties but differ in the relative number of hydroxyl groups present in each material. Thus, their sorption capacities were studied as a function of their textural and chemical properties. Their maximum CO2 uptake values showed a strong correlation with an increasing specific surface area, but that property alone could not fully explain the CO2 uptake data. Hence, the specific CO2 uptake, combined with DFT calculations, indicated that the relative number of hydroxyl groups in the COF backbone acts as an adsorption threshold, as the hydroxyl groups were indeed identified as relevant adsorption sites in all the studied COFs. Additionally, the best performing COF was thoroughly investigated, experimentally and theoretically, for its CO2 capture properties in a variety of CO2 concentrations and temperatures, and showed excellent isothermal recyclability up to 3 cycles. 相似文献
33.
We are interested to the multifractal analysis of inhomogeneous Bernoulli products which are also known as coin tossing measures.
We give conditions ensuring the validity of the multifractal formalism for such measures. On another hand, we show that these
measures can have a dense set of phase transitions. 相似文献
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We consider discretized Hamiltonian PDEs associated with a Hamiltonian function that can be split into a linear unbounded operator and a regular nonlinear part. We consider splitting methods associated with this decomposition. Using a finite-dimensional Birkhoff normal form result, we show the almost preservation of the actions of the numerical solution associated with the splitting method over arbitrary long time and for asymptotically large level of space approximation, provided the Sobolev norm of the initial data is small enough. This result holds under generic non-resonance conditions on the frequencies of the linear operator and on the step size. We apply these results to nonlinear Schrödinger equations as well as the nonlinear wave equation. 相似文献
37.
Boris Gouilleux Benoît Charrier Serge Akoka Patrick Giraudeau 《Magnetic resonance in chemistry : MRC》2017,55(2):91-98
Benchtop NMR emerges as an appealing alternative to widely extend the scope of NMR spectroscopy in harsh environments and for on‐line monitoring. Obviously, the use of low‐field magnets induces a dramatic reduction of the spectral resolution leading to frequent peak overlaps. This issue is even more serious because applications such as chemical process monitoring involve the use of non‐deuterated solvents, leading to intense and broad peaks overlapping with the signals of interest. In this article, we highlight the need for efficient suppression methods compatible with flowing samples, which is not the case of the common pre‐saturation approaches. Thanks to a gradient coil included in our benchtop spectrometer, we were able to implement modern and efficient solvent suppression blocks such as WET or excitation sculpting to deliver quantitative spectra in the conditions of the on‐line monitoring. While these methods are commonly used at high field, this is the first time that they are investigated on a benchtop setting. Their analytical performance is evaluated and compared under static and on‐flow conditions. The results demonstrate the superiority of gradient‐based methods, thus highlighting the relevance of implementing this device on benchtop spectrometers. The comparison of major solvent suppression methods reveals an optimum performance for the WET‐180‐NOESY experiment, both under static and on‐flow conditions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Rate constants for the reaction OH + CO have been measured as functions of temperature (340–1220 K) and water concentration in the presence of 1 atm of argon. Results at zero water concentration yield the expression, log k? (cm3 molecule?1 S?1) = ?12.96 + 4.7 × 10?4 T, for the reaction rate constant as a function of temperature. These results are in very good agreement with previous direct measurements and in reasonable agreement with flame and shock tube measurements. Explanations are offered for the involvement of the water molecule in the present experiments and earlier measurements from this laboratory throughout the entire temperature range. Results are consistent with previous results showing little, if any, pressure effect of Ar on the reaction up to 1 atm of Ar. 相似文献