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collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.Marquès L.Lancia P.Loiseau P.Forestier-colleoni M.Tarisien E.Atukpor V.Bagnoud c.Brabetz F.consoli J.Domange F.hannachi P.Nicolaï M.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance cEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance cENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI helmholtzzentrum für Schwerionenforschung Gmbh Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly cELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

we have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(cSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for cSA.

关键词： acceleration hydrodynamic collision

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OPTIMAL AND PRESSURE-INDEPENDENT L2 VELOcITY ERROR ESTIMATES FOR A MODIFIED cROUZEIX-RAVIART STOKES ELEMENT wITh BDM REcONSTRUcTIONS

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Journal of computational Mathematics 2015年第2期33卷 191-208页

作者： c. Brennecke A. Linke c. Merdon J. Schoberl Eidgen6ssische Technische hochschule Ziirich Departement Mathematik Riimistr. 101 8092 Ziirich Switzerland weierstrass Institute for Applied Analysis and Stochastics Mohrenstr. 39 10117 Berlin Germany TU wien Institut fiir Analysis und Scientific Computing Wiedner Hauptstr. 8-10//1011040 Wien Austria

Nearly all inf-sup stable mixed finite elements for the incompressible Stokes equations relax the divergence constraint. The price to pay is that a priori estimates for the ve- locity error become pressure-dependent, while divergence-free mixed finite elements de- liver pressure-independent estimates. A recently introduced new variational crime using lowest-order Raviart-Thomas velocity reconstructions delivers a much more robust modi- fied crouzeix-Raviart element, obeying an optimal pressure-independent discrete h1 ve- locity estimate. Refining this approach, a more sophisticated variational crime employing the lowest-order BDM element is proposed, which also allows proving an optimal pressure- independent L2 velocity error. Numerical examples confirm the analysis and demonstrate the improved robustness in the Navier-Stokes case.

关键词： Variational crime crouzeix-Raviart finite element Divergence-free mixed me-thod Incompressible Navier-Stokes equations A priori error estimates.

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Vibrational characteristics of piping system in air conditioning outdoor unit

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Science china(Technological Sciences) 2011年第5期54卷 1154-1168页

作者： S. K. LOh w. F. FARIS M. hAMDI w. M. chIN Department of Engineering Design & Manufacture Faculty of Engineering University of Malaya Department of Mechanical Engineering College of Engineering International Islamic University Malaysia O.Y.L. R&D Sdn Bhd Sungai Buloh Selangor Darul Ehsan Malaysia

The modal analysis of piping system in air conditioner (Ac) outdoor unit is essential to investigate the vibration properties of the system. In view of the growing significance of numerical finite element (FE) model for vibration behaviour prediction, the Ac piping elastic end support characterization has been explored. The axial and radial stiffness variables (ka, kr1, kr2) of the compressor-piping mounting are obtained and represented by dynamic stiffness of compressor grommet. They are obtained from dynamic load deflection test based on compressor operating condition such as excitation frequency and amplitude. The unknown stiffness variables of the other tube end (chassis-piping mounting) are determined by parameter fine tuning. An experimental modal analysis using impact hammer test has also been employed to determine the vibration properties such as natural frequencies, mode shapes and damping ratio of the piping structures. The modal parameters acquisition using ScADAS mobile acquisition system and LMS Impact Testing software is compared with the corresponding simulated modal properties using Abaqus. Most of the simulated natural frequencies achieve good correlation with the measured frequencies and it is reasonably a good prediction model to predict vibration behaviour of Ac piping structures.

关键词： air conditioning outdoor unit piping modal analysis vibration characteristics

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high Temperature Oxidation as a Production Route for Electronic Materials

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中国腐蚀与防护学报 2009年第4期29卷 248-252页

作者： w. GAO Z. w. LI Department of chemical and Materials Engineering The University of Auckland Private Bag 92019 Auckland New Zealand BRANZ Ltd Judgeford Porirua 5381 Private Bag 50908 New Zealand

Oxidation of metallic components often results in degradation and structural failure,prevention is therefore an important *** the other hand,oxidation process creates new products such as metal oxides,can be used as a production route.A well-known process in semiconductor industry is that oxidation in dry or wet atmosphere is a popular way for growth of multi-functional SiO_2 films on Si wafers. Recently,oxidation processes under controlled conditions(atmosphere,temperature,and time) are used to prepare various oxides,carbides,or nitrides with micro-/nano-struetures,well-defined composition,dimension, shape and *** use of oxidation now includes thin film and nano-/micro-sized devices, and porous oxides for sensing and catalysis *** paper introduces the research activities in the authors' group on applications of oxidation as a tool for synthesis of functional materials.

关键词：金属腐蚀保护氧化

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cytochrome P450 levels are altered in patients with esophageal squamous-cell carcinoma

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world Journal of Gastroenterology 2007年第7期13卷 997-1002页

作者： I Bergheim E wolfgarten E Bollschweiler Ah hlscher c Bode A Parlesak Department of Physiology of Nutrition Hohenheim University (140e) Stuttgart 70599 Germany Department of Visceral and Vascular Surgery University of Cologne Cologne Germany

AIM： To investigate the role of cytochrome P450 （cYP） in the carcinogenesis of squamous-cell carcinoma （Scc） in human esophagus by determining expression patterns and protein levels of representative cYPs in esophageal tissue of patients with Scc and controls. METhODS： mRNA expression of cYP2E1, cYP2c, cYP3A4, and cYP3A5 was determined using RT-PcR in both normal and malignant esophageal tissues of patients with untreated esophageal Scc （/7 = 21） and in controls （n = 10）. Protein levels of cYP2E1, cYP2cS, cYP3A4, and cYP3A5 were measured by western blot. RESULTS： within the group of Scc patients, mRNA expression of cYP 3A4 and cYP2c was significantly lower in malignant tissue （-39% and -74%, respectively, P 〈 0.05） than in normal tissue. Similar results were found in cYP3A4 protein levels. Between groups, cYP3A4, cYP3A5, and cYP2c8 protein concentration was significantly higher in non-malignant tissue of Scc patients （4.8-, 2.9-, and 1.9-fold elevation, P 〈 0.05） than in controls. In contrast, cYP2E1 protein levels were significantly higher in controls than in Scc patients （＋46%, P 〈 0.05）. cONcLUSION： Significant differences exist in protein levels of certain cYPs in non-malignant esophageal tissue （e.g. cYP2cB, cYP3A4, cYP3A5, and cYP2E1） between Scc patients and healthy subjects and may contribute to the development of Scc in the esophagus.

关键词： Squamous-cell carcinoma cytochrome P450 western blot RT-PcR human

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Integrating multiple images in a sampled phase-only hologram

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chinese Optics Letters 2019年第5期17卷 11-14页

作者： P. w. M. Tsang T.-c. Poon w. wang X. Zhu K. chan Department of Electronic Engineering City University of Hong KongHong Kong SARChina Bradley Department of Electrical and computer Engineering Virginia TechBlacksburgVirginia 24061USA hong Kong Applied Science and Technology Research Institute company Limited Hong Kong SARChina

Past research has demonstrated that a sampled phase-only hologram (SPOh) is capable of representing an image without the magnitude component of the hologram. At present, an SPOh can only record and reconstruct a single source image. In this Letter, we propose, for the first time, to the best of our knowledge, a method for representing multiple images with a single integrated SPOh (ISPOh). Subsequently, each image can be retrieved from the ISPOh with a unique key parameter and displayed as a visible image on a phase-only spatial light modulator.

关键词： Integrating multiple images sampled phase-only hologram magnitude component

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Misorientation dependent thermal condition-solute field cooperative effect on competitive grain growth in the converging case during directional solidification of a nickel-base superalloy

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Journal of Materials Science & Technology 2022年第1期96卷 151-159页

作者： X.B.Meng J.G.Li c.N.Jing J.D.Liu S.Y.Ma J.J.Liang c.w.Zhang M.wang B.T.Tang T.Lin J.L.chen X.L.Zhang Q.Li School of Mechanical and Automotive Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Shandong Jianzhu UniversityJinan 250014China AEcc Shenyang Liming Aero-Engine co. LTD.Shenyang110043China college of Material Science and Engineering North Minzu UniversityYinchuan 750021China Faculty of electro-mechanical information Weifang University of Science and TechnologyShouguang262700China

Nowadays,thermal condition and solute field are considered as the potential dominant factors controlling competitive grain growth during directional solidification ***,the controlling modes and critical conditions of competitive grain growth have been drastically debated over the past two *** this work,thermal condition and solute field are combined to study the competitive grain growth in the converging case by experimental observation and numerical simulation of bicrystal *** find the competitive grain growth is controlled by the cooperative effect of thermal condition and solute field,and the controlling modes are related to the bicrystal misorientation between favorably and unfavorably oriented *** the unfavorably oriented grain is low misoriented,unfavorably oriented grain dominates grain selection,and the competitive grain growth performs as solute field ***,with the increase of unfavorably oriented grain’s misorientation,the grain selection converts into favorably oriented grain domination,and the competitive grain growth changes to thermal condition *** explain these abnormal transformation phenomena,we propose a misorientation dependent thermal condition-solute field cooperative domination model and identify the critical conditions by a critical misorientation(θ_(cm)).According to dynamic equation of dendrite growth,we calculate the critical misorientationθ;to prove this *** theoretical calculation results agree well with the experimental results.

关键词： competitive grain growth cooperative effect Thermal condition Solute field critical misorientation Unusual overgrowth Abnormal transformation

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SURFAcE MORPhOLOGY OF SELF-ASSEMBLED VERTIcALLY STAcKED InAs QUANTUM DOTS BY SIZE-cONTROLLED GROwTh

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 189-193页

作者： S.w.Li K.Koike StateKeyLaboratoryofOptoelectronicMaterialsandTechnologies Zhongshan（SunYat-sen）UniversityGuangzhou510275China NewMaterialsResearchcenter OsakaInstituteofTechnologyAsahi-kuOhmiyaOsaka535-8585Japan

Structural and optical properties of vertically aligned InAs quantum dots (QDs) were embedded in Al0.5Ga0.5As spacer layers. The aligned QDs were grown at 520℃ in the Stranski-Krastanow (S-K) growth mode of molecular beam epitaxy. To impro ve QD characteristics, we employed a size- and density-controlled growth procedu re in the upper layers. Measurements by reflection high-energy electron diffract ion (RhEED) and atomic force microscopy (AFM) showed that both the size and dens ity of the QDs. The temperature dependence of the wavelength-integrated photolum inescence (PL) intensity revealed the InAs QD emission.

关键词： quantum dot molecular beam epitaxy atomic force microscopy photoluminescence

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hydrodynamics of the interceptor on a 2-D flat plate by cFD and experiments

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Journal of hydrodynamics 2015年第6期27卷 919-933页

作者： MANSOORI M. FERNANDES A.c. Department of Naval and Ocean Engineering Federal University of Rio de Janeiro

Nowadays, the use of interceptor by both partial and total dynamic lift crafts is quite common. In this article, a lot of evidence is given regarding the effectiveness of interceptor. The interceptor, when placed at the stern region, changes the pressure distribution around the craft. Its presence affects drag force, lifting force and the position of pressure＇s center leading to a new trim. This study focuses on hydrodynamic effects of interceptors on a 2-D fiat plate based on both computational fluid dynamic （cFD） and experimental approaches. The Reynolds average Navier-Stokes （RANS） equations are used to model the flow around a fixed flat plate with an interceptor at different heights and attack angles. Based on finite volume method and SIMPLE algorithm which uses static structures, this model can be analyzed and the RANS results can be compared with the experimental data obtained in the current channel of the laboratory of waves and current of cOPPE/UFRJ （LOc in Portuguese acronym）. According to the results, the increase of pressure at the end of the flat plate was proportional to the interceptor height. In addition, the existence of interceptors can significantly increase the lift force coefficient at high angles of attack also proportional to the interceptor height. The presence of interceptor at the end of the fiat plate increased both the lift coefficient and the drag coefficient but hydrodynamic drag did not grow as fast as the lift coefficient did. The lift coefficient increased much more. Furthermore, the results showed that the interceptor effectiveness is proportional to the boundary layer thickness at the end of the fiat plate. As the interceptor was inside the boundary layer alterations of flow speed led to changes in boundary layer thickness, directly affecting interceptor＇s efficiency. Optimum choice of interceptor height had a great effect on its efficiency, and in choosing it the flow speed and length of the boat must be taken into consideration.

关键词： interceptor craft 2-D fiat plate lifting coefficient Reynolds average Navier-Stokes (RANS) pressure distribution,computational fluid dynamic drag

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Solution of Dirac equation for Eckart potential and trigonometric Manning Rosen potential using asymptotic iteration method

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chinese Physics B 2016年第1期25卷 428-435页

作者： resita arum sari a suparmi c cari Physics Department Sebelas Maret UniversityJ1.Ir.Sutami 36A Kentingan Surakarta 57126Indonesia

The Dirac equation for Eckart potential and trigonometric Manning Rosen potential with exact spin symmetry is obtained using an asymptotic iteration method. The combination of the two potentials is substituted into the Dirac equation, then the variables are separated into radial and angular parts. The Dirac equation is solved by using an asymptotic iteration method that can reduce the second order differential equation into a differential equation with substitution variables of hypergeometry type. The relativistic energy is calculated using Matlab 2011. This study is limited to the case of spin symmetry. with the asymptotic iteration method, the energy spectra of the relativistic equations and equations of orbital quantum number l can be obtained, where both are interrelated between quantum numbers. The energy spectrum is also numerically solved using the Matlab software, where the increase in the radial quantum number nr causes the energy to decrease. The radial part and the angular part of the wave function are defined as hypergeometry functions and visualized with Matlab 2011. The results show that the disturbance of a combination of the Eckart potential and trigonometric Manning Rosen potential can change the radial part and the angular part of the wave function.

关键词： Dirac equation Eckart potential trigonometric Manning Rosen potential spin symmetric

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