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排灌机械工程学报 2016年第12期34卷 1013-1021页

作者： SI Qiaorui DAZIN Antoine DUPONT Patrick ROUSSETTE Olivier BOIS Gérard national Research Center of Pumps Jiangsu University laboratoire de Mécanique de Lille (UMR CNRS 8107) Arts et Métiers ParisTech laboratoire de Mécanique de Lille(UMR CNRS 8107) Ecole Centrale de Lille

Experimental investigation of mean flow velocity and pressure inside the vane-island type diffuser passage of a test centrifugal pump model is presented.A directional three-hole probe was used to investigate hub-to-shroud flow properties at diffuser leading and trailing edge *** addition,the mid-section between suction and pressure sides along the diffuser passage was also *** these measurements were performed at five different flow *** flow structures at the inlet section of the diffuser and along with the passage were analyzed in detail,with a focus on the flow distribution and the pressure recovery evolution of different diffuser *** and distortion effects were analyzed by using existing published particle image velocimetry(PIV)measurements in the outer part of the impeller and around the diffuser throat in order to get a better understanding of the overall performances and local flow structures of such a diffuser *** results show that back flows occur on the shroud region from impeller exit plane up to the semi-vaneless part of the diffuser at low flow *** blockage effects combining with blade thickness geometrical blockage tend to diminish the effects of theoretical high positive *** high flow rates,negative incidence effects induce high local velocity on the pressure side of the diffuser just after the *** aerodynamic blockage associated with low flow distortions are found to have a beneficial effect on pressure recovery for low flow *** the contrary,high flow distortions are found for increased flow rates,resulting in a low pressure recovery inside the semi-vane less part of the diffuser and after the throat.

关键词： vane island diffuser flow structure pressure recovery three-hole probe particle image velocimetry

RecQ Helicase-catalyzed DNA Unwinding detected by Fluorescence Resonance Energy Transfer

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Acta Biochimica et Biophysica Sinica 2005年第9期37卷 593-600页

作者： Xing-Dong ZHANG Shuo-Xing DOU Ping XIE Peng-Ye WANG Xu Guang XI Laboratory of Soft Matter Physics,Beijing national Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100080,China laboratoire de Biotechnologies et Pharmacologie Génétique Appliquée CNRS UMR 8113.Ecole Normale Supérieure de Cachan,61 Avenue du Président Wilson,94235 Cachan cedex,France Laboratory of Soft Matter Physics Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of SciencesBeijing 100080 China laboratoire de Biotechnologies et Pharmacologie Génétique Appliquée CNRS UMR 8113 Ecole Normale Supérieure de Cachan61 Avenue du Président Wilson 94235 Cachan cedex France

A fluorometric assay was used to study the DNA unwinding kinetics induced by Escherichiacoli RecQ *** assay was based on fluorescence resonance energy transfer and carried out onstopped-flow,in which DNA unwinding was monitored by fluorescence emission enhancement of fluoresceinresulting from helicase-catalyzed DNA *** this method,we determined the DNA unwinding rateof RecQ at different enzyme *** also studied the dependences of DNA unwinding magnitudeand rate on magnesium ion *** showed that this method could be used to determine thepolarity of DNA *** assay should greatly facilitate further study of the mechanism for RecQ-catalyzed DNA unwinding.

关键词： helicase DNA unwinding kinetics stopped-flow fluorescence resonance energy transfer (FRET)

Carabidae et Trechidae nouveaux des collections entomologiques de la North-West Agricultural University de Yangling, Shaanxi (Coleoptera)

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昆虫分类学报 1989年第3期 227-233页

作者： par Thierry deuve laboratoire d’Entomologic Museum national d’Histoirc naturelle 75005 Paris France

In this work are described and illustrated five new species from the Qin Ling Mountains (China, Shaanxi Province):Carabus (Eucarabus) choui n. sp., Cychrus sinicus n. sp.,Cychrus bispinosus n. sp., Agonotrechus sinicola ***., Trechus zhangi ***. The holotypes are conserved in the entomological collections of the Northwestern Agricultural University (department of Plant Protection).

关键词： Plus Shaanxi West Coleoptera Carabidae et Trechidae nouveaux des collections entomologiques de la North-West Agricultural University de Yangling

Quasi-hydrostatic Primitive Equations for Ocean Global Circulation Models

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Chinese Annals of Mathematics,Series B 2010年第6期31卷 939-952页

作者： Carine LUCAS Madalina PETCU Antoine ROUSSEAU laboratoire MAPMO (UMR 6628) Fédération Denis Poisson (FDP-FR2964) Université d'OrléansBtiment de Mathématiques-Route de Chartres B. P. 6759 45067 Orléans Cedex 2 France laboratoire de Mathématiques et Applications Téléport 2-B. P. 30179 Boulevard Marie et Pierre Curie 86962 Futuroscope Chasseneuil Cedex France INRIA Laboratoire Jean Kuntzmann 51 rue des Mathématiques B. P. 53 38041 Grenoble Cedex 9France

Global existence of weak and strong solutions to the quasi-hydrostatic primitive equations is studied in this paper. This model, that derives from the full non-hydrostatic model for geophysical fluid dynamics in the zero-limit of the aspect ratio, is more realistic than the classical hydrostatic model, since the traditional approximation that consists in neglecting a part of the Coriolis force is relaxed. After justifying the derivation of the model, the authors provide a rigorous proof of global existence of weak solutions, and well-posedness for strong solutions in dimension three.

关键词： Hydrostatic approximation Coriolis force Ocean global circulation models Primitive equations Traditional approximation

Monte Carlo study of nanowire magnetic properties

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Chinese Physics B 2013年第5期22卷 514-518页

作者： R. Masrour L. Bahmad A. Benyoussef laboratoire de Magnétisme et Physique des Hautes Energies URAC 12Université Mohammed V-AgdalFaculté des Sciences Laboratory of Materials ProcessEnvironment and QualityCady Ayyad UniversityNational School of Applied Sciences

In this work, we use Monte Carlo simulations to study the magnetic properties of a nanowire system based on a honeycomb lattice, in the absence as well as in the presence of both an external magnetic field and crystal field. The system is formed with NL layers having spins that can take the values σ= ± 1/2 and S =±1,0. The blocking temperature is deduced, for each spin configuration, depending on the crystal field A. The effect of the exchange interaction coupling Jp between the spin configurations σ and S is studied for different values of temperature at fixed crystal field. The established ground-state phase diagram, in the plane （Jp, △）, shows that the only stable configurations are：（1/2,0）, （1/2, ＋1）, and （1/2,- 1）. The thermal magnetization and susceptibility are investigated for the two spin configurations, in the absence as well as in the presence of a crystal field. Finally, we establish the hysteresis cycle for different temperature values, showing that there is almost no remaining magnetization in the absence of the external magnetic field, and that the studied system exhibits a super-paramagnetic behavior.

关键词： Monte Carlo simulations nanowire magnetic field crystal field

Case Study for Undetermined Mosquito Species by Polymerase Chain Reaction in Western Burkina Faso

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American Journal of Molecular Biology 2024年第2期14卷 43-53页

作者： Koudraogo Bienvenue Yaméogo Sassan Simplice Kambou Domonbabélé François de Sales Hien Logotio Rachel Angela Traore Franck Adama Yao Rakiswendé Serge Yerbanga Centre national de la Recherche Scientifique et Technologique CNRST Institut de Recherche en Sciences de la Sante (IRSS) Laboratoire de recherche sur les maladies infectieuses et parasitaires Bobo-Dioulasso Burkina Faso Institut des Sciences et Techniques (INSTech Bobo) Avenue de Sya Bobo-Dioulasso Burkina Faso

Introduction: Malaria eradication campaigns all over the world are largely based on parasite and vector control. Vector identification, whether morphological or molecular, is an essential component of vector control. This study analyzed the possible causes of indeterminate polymerase chain reaction (PCR) results for mosquito species in Western part of Burkina Faso. Methodology: From July 2021 to November 2021, mosquitoes were collected during the period of high malaria transmission in the village of Séguéré, Houet province, Burkina Faso, and morphologically identified. After DNA extraction, samples were amplified by sine 200× PCR to identify species of the Anopheles gambiae complex. Indeterminate samples were then selected for further analysis. The parameters studied were: DNA dilution, the effect of protocol adjusting, and the type of protocol used. Results: A total of 130 “indeterminate” DNAs diluted 1:10 were analyzed. After dilution, the mean amount was 14.73 ± 3.59 ng/μL and absorbance 1.71 ± 0.1. PCR chain reaction yielded 94.62% (123/130) anopheline species in SINE PCR, 5.38% (7/130) “negative”. A significant difference between SINE PCR before dilution and after dilution was observed (P dentification tests carried out using other protocols gave no positive results. From these results, we note that the adaptation of the protocol significantly reduced the polymerase amplification results of the species. Conclusion: It is therefore necessary to respect the amplification protocols. However, the persistence of “indeterminate” results suggests that further studies should be carried out to shed more light on the subject.

关键词： Malaria Vector DNA PCR

The Tychonoff uniqueness theorem for the G-heat equation

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Science China Mathematics 2011年第3期54卷 463-468页

作者： LIN Qian1,2 1School of Mathematics, Shandong University, Jinan 250100, China 2 laboratoire de Mathématiques, CNRS UMR 6205, Université de Bretagne Occidentale, 6, avenue Victor Le Gorgeu, CS 93837, 29238 Brest cedex 3, France School of Mathematics Shandong University Jinan China laboratoire de Mathématiques CNRS UMR 6205 Université de Bretagne Occidentale Brest cedex 3 France

In this paper we shall investigate a uniqueness result for solutions of the G-heat equation. We obtain the Tychonoff uniqueness theorem for the G-heat equation.

关键词： Tychonoff uniqueness theorem G-heat equation G-expectations G-Brownian motion viscosity solutions

An update on histone lysine methylation in plants

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Progress in Natural Science:Materials International 2009年第4期19卷 407-413页

作者： Yu Yu a, Zhongyuan Bu a, Wen-Hui Shen b, Aiwu Dong a,a State Key Laboratory of Genetic Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China b Institut de Biologie Moléculaire des Plantes (IBMP), laboratoire Propre du CNRS (UPR 2357) conventionné avec l’Université LouisPasteur Strasbourg, 67084 Strasbourg Cédex, France State Key Laboratory of Genetic Engineering Institute of Plant Biology School of Life Sciences Fudan University Shanghai 200433 China Institut de Biologie Moléculaire des Plantes (IBMP) Laboratoire Propre du CNRS (UPR 2357) conventionné avec l’Université Louis Pasteur Strasbourg 67084 Strasbourg Cédex France

Histone methylation plays crucial roles in epigenetic regulation. The SET domain proteins are now recognized as generally having methyltransferase activity targeted to specific lysine residues of histones. The enzymes and their specific histone lysine methylation have enormous impacts on the regulation of chromatin structure and function. In this review, we discuss recent advances made on histone lysine methylations and their diverse functions in plant growth and development.

关键词： Chromatin modification Histone Lysine methylation SET domain protein Plant

Synthesis and spectroscopic characterization of cobalt porphyrins and their catalytic activity towards dioxygen reduction

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Chinese Journal of Chemistry 1992年第4期10卷 309-319页

作者： GUILARD,Roger BARBE,Jean-Michel laboratoire de Synthese et d’Electrosynthese Organometalliques,Associe au C.N.R.S.,URA 33,6,Bd Gabriel,21100,Dijon,FranceDONG,Shao-Jun QIU,Qing-Sheng Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China laboratoire de Synthese et d'Electrosynthese Organometalliques Associe au C. N. R. S. URA 33 6 Bd Gabriel 21100 Dijon France Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The synthesis and spectroscopic characterization of cobalt(Ⅱ) 5-(4-pyridyl)-10,15,20-triphe- nylporphyrin,cobalt(Ⅱ) 5-(4-N-hexadecylpyridiniumyl)-10,15,20-triphenylporphyrin bromide and cobalt(Ⅱ) 5-(2-aminophenyl)-10,15,20-triphenyl-porphyrin are *** corresponding copper and vanadyl derivatives ((TriP)Cu,[(hTriP)Cu]^+Br^- and [(hTriP)VO]^+Br^-) were also *** metalloporphyrin was characterized by UV-visible,ESR and ~1H NMR *** me- talloporphyrins can be firmly adsorbed on the glassy carbon (GC) *** catalytic reduction of dioxygen at GC electrodes modified by these catalysts was studied by cyclic voltammetry (CV).The kinetic process of dioxygen reduction at the cobalt porphyrin-modified electrodes was studied with a rotating ring disk electrode.

关键词： GC rate Co Synthesis and spectroscopic characterization of cobalt porphyrins and their catalytic activity towards dioxygen reduction