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991.
Camille Hespel Jean-Bernard Blaisot Matthieu Gazon Gilles Godard 《Experiments in fluids》2012,53(1):245-264
The characterization of diesel jets in the near field of the nozzle exit still presents challenges for experimenters. Detailed velocity measurements are needed to characterize diesel injector performance and also to establish boundary conditions for CFD codes. The present article examines the efficiency of laser correlation velocimetry (LCV) applied to diesel spray characterization. A new optical configuration based on a long-distance microscope was tested, and special care was taken to examine the spatial selectivity of the technique. Results show that the depth of the measurement volume (along the laser beam) of LCV extends beyond the depth of field of the imaging setup. The LCV results were also found to be particularly sensitive to high-speed elements of a spray. Results from high-pressure diesel jets in a back-pressure environment indicate that this technique is particularly suited to the very near field of the nozzle exit, where the flow is the narrowest and where the velocity distribution is not too large. It is also shown that the performance of the LCV technique is controlled by the filtering and windowing parameters used in the processing of the raw signals. 相似文献
992.
993.
Pierre Gilles Lemarié-Rieusset 《Journal of Functional Analysis》2018,274(3):659-694
We develop a general framework to describe global mild solutions to a Cauchy problem with small initial values concerning a general class of semilinear parabolic equations with a quadratic nonlinearity. This class includes the Navier–Stokes equations, the subcritical dissipative quasi-geostrophic equation and the parabolic–elliptic Keller–Segel system. 相似文献
994.
Electrochemical Properties of Substituted 2‐Methyl‐1,4‐Naphthoquinones: Redox Behavior Predictions 下载免费PDF全文
Dr. Mourad Elhabiri Pavel Sidorov Elena Cesar‐Rodo Dr. Gilles Marcou Dr. Don Antoine Lanfranchi Dr. Elisabeth Davioud‐Charvet Dr. Dragos Horvath Prof. Alexandre Varnek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3415-3424
In the context of the investigation of drug‐induced oxidative stress in parasitic cells, electrochemical properties of a focused library of polysubstituted menadione derivatives were studied by cyclic voltammetry. These values were used, together with compatible measurements from literature (quinones and related compounds), to build and evaluate a predictive structure–redox potential model (quantitative structure–property relationship, QSPR). Able to provide an online evaluation (through Web interface) of the oxidant character of quinones, the model is aimed to help chemists targeting their synthetic efforts towards analogues of desired redox properties 相似文献
995.
996.
We prove a unique continuation property for solutions of Stokes equations with a non regular potential. For this, we state a Carleman's inequality which concerns the Laplace operator. 相似文献
997.
We report the extension of an easy one-step synthesis of amino gem-bisphosphonates through the reaction of amides and lactams with trialkylphosphites. 相似文献
998.
999.
Marie-Aude Ploix Philippe Guy Bertrand Chassignole Joseph Moysan Gilles Corneloup Rachid El Guerjouma 《Ultrasonics》2014
Multipass welds made of 316L stainless steel are specific welds of the primary circuit of pressurized water reactors in nuclear power plants. Because of their strong heterogeneous and anisotropic nature due to grain growth during solidification, ultrasonic waves may be greatly deviated, split and attenuated. Thus, ultrasonic assessment of the structural integrity of such welds is quite complicated. Numerical codes exist that simulate ultrasonic propagation through such structures, but they require precise and realistic input data, as attenuation coefficients. This paper presents rigorous measurements of attenuation in austenitic weld as a function of grain orientation. In fact attenuation is here mainly caused by grain scattering. Measurements are based on the decomposition of experimental beams into plane-wave angular spectra and on the modeling of the ultrasonic propagation through the material. For this, the transmission coefficients are calculated for any incident plane wave on an anisotropic plate. Two different hypotheses on the welded material are tested: first it is considered as monoclinic, and then as triclinic. Results are analyzed, and validated through comparison to theoretical predictions of related literature. They underline the great importance of well-describing the anisotropic structure of austenitic welds for UT modeling issues. 相似文献
1000.
Pierre Gilles Lemarié–Rieusset Frédéric Lelièvre 《Communications in Mathematical Physics》2011,307(1):133-156
This paper is devoted to the study of strong or weak solutions of the Navier–Stokes equations in the case of an homogeneous
initial data. The case of small initial data is discussed. For large initial data, an approximation is developed, in the spirit
of a paper of Vishik and Fursikov. Qualitative convergence is obtained by use of the theory of Muckenhoupt weights. 相似文献