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Chinese Physics Letters 2005年第1期22卷 69-71页

作者： f.N.Khattak e.U.Khan TabassumNasir J.J.Baluch f.U.Khan U.W.C. GomalUniversityDeraIsmailKhanPakistan RadiationPhysicsDivision PINSTECHNiloreIslamabadPakistan DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan

Two detector materials mica and cellulose-nitrate(CN)-85 have been used to study (14.0MeV/u) Pb + Pb reaction. events of different multiplicities were registered in mica and CN-85 detectors using the 2π-geometry technique of solid state nuclear track detection. After removing the target material from the detectors the damaged trails in the detectors were revealed as tracks by proper chemical etching. The irradiated area of each sample was scanned and events of different multiplicities were traced. The binary events were bifurcated into elastic and inelastic events. The elastic binary events and three prong events, observed in the reaction, have been used to search out coefficients Cμν in the presence of both the detectors, for the reaction under study. Using these coefficients 3- and 4-prong events have been analysed. from the detailed analysis of the results of (14.0MeV/u) Pb+Pb reaction, obtained from mica and CN-85 track detectors we observed a great resemblance of results obtained from the two detectors. Combining the results of both the detectors, we report some important outcomes.

关键词： CN-85轨迹探测器高能物理学铅原子碰撞反应固态

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Communications in Theoretical Physics 2020年第7期72卷 104-110页

作者： f Ungan M K Bahar S Pal M e Mora-Ramos faculty of Technology Department of Optical EngineeringSivas Cumhuriyet University58140SivasTurkey faculty of Science Department of PhysicsSivas Cumhuriyet University58140 SivasTurkey Department of Quality Assurance CQA(SA)DGQA Ichapur-Nawabganj24Pgs(North)743144West BengalIndia Centro de Investigación en Ciencias Instituto de Investigación en Ciencias Básicas y AplicadasUniversidad Autónoma del Estado de MorelosAv.Universidad 1001CP62209CuernavacaMorelosMexico facultad de Ciencias Básicas Universidad de MedellínMedellinColombia

We present a theoretical study on the effects of intense laser field(ILf)and static electric field on the linear and nonlinear optical properties of a cylindrical quantum dot with Rosen-Morse axial potential under the framework of effective mass and parabolic band *** study also takes into account the effects of the structure parameters(η,V1,and R).The analytical expressions of the linear,third-order nonlinear and total optical absorption coefficients(TOACs)and the relative refractive index changes(RRICs)are obtained by using the compact-densitymatrix *** results of numerical calculations show that the resonant peak position of the TOACs and RRICs shifts towards lower energies and the magnitude of the peak increases with the effect of the static electric field and *** addition,it is observed that while the resonant energies of the TOACs and RRICs of system shift towards the higher(lower)energies with the enhancement ofη,V1,they decrease with the augmentation of ***,the findings of this study show that the optical properties of the structure can be adjusted by changing the magnitude of structure parameters and applied external fields.

关键词： cylindrical quantum dot nonlinear optical response intense laser field electric field

Oxidation Resistance of the Aluminide Coating formed on Carbon Steels

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Journal of Materials Science & Technology 1997年第5期13卷 383-388页

作者： Soliman, H.M. Mohamed, K.e. Abd el-Azim, M.e. Hammad, f.H. Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by the pack aluminizing technique using halideactivated pure-Al and fe-Al packs. The effect of mixture composition, aluminizing temperatureand time and C content of the steel substrate on the structure and thickness of the aluminidelayer, and on the oxidation resistance was investigated. The optimum oxidation resistance canbe achieved with a low carbon steel substrate when the intermetallic phases fe3Al and feAlform the surface of the aluminide layer. In this case, the Al concentration at the surface of thealuminide coating is at least ≥15 wt pct. formation of high Al concentration phases (feAl3 andfe2Al5) during aluminizing should be avoided as they tend to embrittle the aluminide layer andreduce its oxidation resistance.

关键词： OO figure Oxidation Resistance of the Aluminide Coating formed on Carbon Steels

Titanium Alloy Surface Modification by a Spatio-Temporal Atmospheric Pressure DBD Afterglow

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Plasma Science and Technology 2007年第6期9卷 670-673页

作者： e.PANOUSIS f.CLeMeNT J.f.LOISeAU N.SPYROU B.HeLD J.LARRIeU f.GUeRTON Laboratory of Gas electronics and Plasmas-Pau University 64000 PauFrance Electrotechnic Materials LaboratoryUniversity of Patras26500 Patras-RioGreece Laboratory of Gas electronics and Plasmas-Pau University 64000 PauFrance electrotechnic Materials Laboratory University of Patras26500 Patras-RioGreece Laboratoire Interdisciplinaire de Spectroscopie electronique University of Namur5000 NamurBelgium

The experimental work reported here is devoted to the study of the modifications inflicted on the surface of titanium alloy specimens by an atmospheric pressure dielectric barrier discharge（DBD） reactor in both spatial and temporal afterglow conditions. A commercially available （AcXys Technologies） modified reactor system was used for the surface treatment of the TiA6V4 titanium alloy that is widely used in the aeronautical industry. Wettability surface characterisation and XPS analyses are performed to give a macroscopic and microscopic insight to the surface modifications. Best operating conditions, at constant input energy, were obtained for a duty cycle equal to 10%.

关键词： DBD titanium alloy atmospheric pressure

Selective sphincteroplasty of the papilla in cases at risk due to atypical anatomy

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World Journal of Gastroenterology 2007年第22期13卷 3106-3111页

作者： f Mugica G Urdapilleta A Castiella A Berbiela f Alzate e Zapata L Zubiaurre P Lopez JI Arenas Gastroenterology Department Donostia Hospital San Sebastian Spain Department Donostia Hospital San Sebastian Spain Gastroenterology Department Bajo Deva Hospital Spain Anaesthesia Department Donostia Hospital San Sebastian Spain

AIM： To analyze the indications, efficacy and safety of sphincteroplasty in our centre.MeTHODS： A retrospective study of sphincteroplasty in 53 cases of papilla at high risk was performed in 2004-2006. The procedure consisted of duodenoscopy with Olympus TJf 145 Videoduodenoscope, approach to the biliary tract using a catheter with a guidewire, and dilatation of the papilla with a dilatation balloon catheter using a syringe with a manometer for control of the filling pressure.ReSULTS： The indications included intradiverticular papilla in 26 patients （49%）, stenosis of a previous sphincterotomy in 19 patients （35.8%）, small size of the papilla in 4 patients （7.5%）, Billroth R gastrectomy in 3 patients （5.6%）, and coagulopathy in one patient （1.9%）. The efficacy was 97.8%, with all the calculi extracted from the common bile duct in 84.4% of the patients, even though 21 of the patients （39.6%） had calculi with a diameter equal to or greater than 10 ram. Seven patients （13.2%） presented complications： haemorrhage in 1 patient （1.9%） and mild pancreatitis in 6 patients （11.3%）. The mean hospital stay in case of complications was of 3 ± 0.63 d.CONCLUSION： Sphincteroplasty is highly effective, with a compllcation rate similar to that of sphincterotomy, furthermore, the complications are of low clinical importance. The use of the 10 mm balloon makes it possible to extract calculi with a diameter of over 15 mm and to extract more than 3 calculi without increasing the rate of complications and reduces the need to resort to lithotripsy or rescue sphincterotomy.

关键词： Sphincteroplasty Hydrostatic dilatation of the papilla Choledocholithiasis Sphincterotomy function of the sphincter of Oddi Acute pancreatitis Intradiverticular papilla

Langmuir Probe and Optical emission Spectroscopy Studies of Low-Pressure Gas Mixture of CO_2 and N_2

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Plasma Science and Technology 2010年第3期12卷 314-319页

作者： e.f.MeNDeZ-MARTINeZ P.G.ReYeS D.OSORIO-GONZALeZ f.CASTILLO H.MARTINeZ faculty of Sciences Autonomous University of the State of Mexico Institute of Nuclear Sciences Autonomous National University of Mexico Institute of Physical Sciences Autonomous National University of Mexico

Optical emission spectroscopy was used to study a gas mixture glow discharge of CO2 and N2 at a total pressure of 1.2 Torr, a power of 100 W and a flow of 16.5 L/min. The emission bands were measured in the wavelength range of 200 nm to 900 nm. The principal species observed were O2^＋（A^2П→ X^2П）, CO^＋（A^2П→X^2∑）, N2^＋（B^2∑u＋ → X^2∑g^＋）, CO2^＋（A^2∏ → X^2∏）, N2（C^3∏u → B^3∏g）, O2（b^1∑g^＋→ X^3∑g^-）, and CO （a^r3∑→a^3∏）. The behavior of the band intensities as a function of the N2 percentage is consistent with recent Monte Carlo simulations. The electron temperature and ion density were determined by a double Langmuir probe. The electron temperature was found in the range of 1.55 eV to 2.93 eV, and the electron concentration in the order of 10^10 cm^-3. The electron temperature and ion density at pure N2 and pure CO2 agree with previous measurements.

关键词： optical emission spectroscopy glow discharge electron temperature CO2 N2

effect of Ce-base mischmetal addition on the microstructure and mechanical properties of hot-rolled ZK60 alloy

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Journal of Magnesium and Alloys 2021年第3期9卷 995-1006页

作者： e.P.Silva R.H.Buzolin f.Marques f.Soldera U.Alfaro H.C.Pinto Institute of engineering Science and Technology(IECT)Federal University of Vales do Jequitinhonha e Mucuri(UFVJM)JanaúbaMGBrazil São Carlos School of engineering(eeSC) University of São Paulo(USP)Department of Materials EngineeringCEP 13563-120 São Carlos-SPBrazil Christian Doppler Laboratory for Design of high-performance alloys by thermomechanical processing Kopernikusgasse 24/I8010 GrazAustria Technische Universität Graz(TU Graz) Institute of Materials ScienceJoining and FormingKopernikusgasse 24/I8010 GrazAustria Institute of functional Materials Department of Materials Science and EngineeringSaarland UniversitySaarbrueckenGermany German Aerospace Center(DLR)Institute of Materials Research Linder Höhe51147 CologneGermany

Mg-Zn-Zr(ZK)alloys exhibit notably high mechanical strength amongst all magnesium alloy ***,due to the formation of low melting point Mg_3Zn_7-precipitates,these alloys are susceptible to hot cracking,thus compromising their metallurgical *** addition of rare earths to ZK alloys is an alternative to form higher melting point intermetallic compounds,speed up dynamic recrystallization,refine grain size,enhance corrosion resistance and extend the service temperature due to improved creep *** work deals with the effect of Ce-base mischmetal addition on the hot rolling behaviour of as-cast ZK60 *** microstructure investigation conducted using electron microscopy and X-Ray diffraction shows that precipitation of Mg_(7)Zn_(3) intermetallics occur during hot rolling,whereas no further precipitation is observed for the ZK60-Mm *** fragmentation of the intermetallic compounds occur during hot rolling and finer particles of Mg_(7)Zn_(3) are observed for the ZK60,whereas Mg_(7)Zn_(3) and Mg Zn_(2) Ce intermetallics are formed in the alloy modified with mischmetal addition.A higher fraction of dynamically recrystallized grains is observed for the ZK60-Mm in comparison to the *** recrystallization takes place in ZK60 with the formation of sub-grains near to the intermetallics and the addition of mischmetal promotes the occurrence of discontinuous recrystallization with the nucleation of new grains close to the *** mechanical strength and,in particular,the ductility of the hot-rolled alloys are notably improved when compared to the same alloys in the as-cast *** mechanical strength is,however,higher for the ZK60 *** solid solution strengthening,softer Mg Zn_(2) Ce intermetallics and more extensive recrystallization contribute to reduce the mechanical strength of *** in both alloys are initiated at coarse intermetallics and propagate through intermetallic-rich regions.

关键词： Magnesium alloys Hot rolling Mischmetal Recrystallization Microstructure Mechanical properties

Parameters of a severe disease course in ulcerative colitis

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World Journal of Gastroenterology 2014年第35期20卷 12574-12580页

作者： Andreas Stallmach Luisa Nickel Thomas Lehmann Bernd Bokemeyer Martin Bürger Dietrich Hüppe Wolfgang kruis Susanna Nikolaus Jan C Preiss Andreas Sturm Niels Teich Carsten Schmidt Klinik für Innere Medizin Ⅳ Universit?tsklinikum JenaJena 07747Germany Zentrum für klinische Studien Universit?tsklinikum JenaJena 07747Germany Gastroenterologische Gemeinschaftspraxis Minden 32423Germany Gastroenterologische Gemeinschaftspraxis Herne 44623Germany evangelisches Krankenhaus Kalk K?ln 51103Germany Klinik für Innere Medizin Christian Albrechts-Universit?tKiel 24105Germany Medizinische Klinik I Campus Benjamin FranklinCharitéBerlin 12203Germany Medizinische Klinik Campus Berlin MitteCharitéBerlin 13353Germany Krankenhaus Waldfriede Berlin 14163Germany Internistische Gemeinschaftspraxis für Verdauungsund Stoffwechselkrankheiten Leipzig 04105Germany

AIM: To detect high risk patients with a progressive disease course of ulcerative colitis (UC) requiring immunosuppressive therapy (IT).

关键词： Clinical practice Parameter Prediction model Ulcerative colitis Inflammatory bowel disease

Abnormal austenite-ferrite transformation behavior in pure iron

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Chinese Science Bulletin 2004年第9期49卷 972-975页

作者： LIUYongchang f.Sommer e.J.Mittemeijer CollegeofMaterialSciences&engineering.TianjinUniversity Tian-jin300072China MaxPlanckInstituteforMetalsResearch.HeisenbergStr.3.D-70569Stuttgart Germany

The austenite ferrite transformation is the most important reaction route in the manufacture of fe-based materials. Here the austenite (g) ferrite (a) transformation of pure iron was systematically explored by high-resolution dilatometry. Abnormal transformation ki-netics, multi-peak discontinuous reaction, was recognized in pure iron according to the variation of the ferrite-formation rate. The occurrence the one or the other type of ga trans-formation strongly depends on the grain size: the transfor-mation type changes from abnormal to normal (single-peak continuous reaction) with decreasing grain size. The inherent reason for the occurrence of abnormal transformation could be attributed to the repeated nucleation in front of the mov-ing g/a interface induced by the accumulation of elastic and plastic accommodation energy.

关键词：奥氏体铁氧体纯铁成核作用动力学固相转变微结构

Time-Harmonic Acoustic Scattering in a Complex flow:A full Coupling Between Acoustics and Hydrodynamics

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Communications in Computational Physics 2012年第2期11卷 555-572页

作者： ***-Ben Dhia J.f.Mercier f.Millot *** e.Peynaud POeMS CNRS-INRIA-ENSTA UMR 723132 Boulevard Victor75015 ParisFrance CeRfACS 42Avenue Gaspard Coriolis31057 Toulouse Cedex 01France

for the numerical simulation of time harmonic acoustic scattering in a complex geometry,in presence of an arbitrary mean flow,the main difficulty is the coexistence and the coupling of two very different phenomena:acoustic propagation and convection of *** consider a linearized formulation coupling an augmented Galbrun equation(for the perturbation of displacement)with a time harmonic convection equation(for the vortices).We first establish the well-posedness of this time harmonic convection equation in the appropriatemathematical *** the complete problem,with Perfectly Matched Layers at the artificial boundaries,is proved to be coercive+compact,and a hybrid numerical method for the solution is proposed,coupling finite elements for the Galbrun equation and a Discontinuous Galerkin scheme for the convection *** a 2D numerical result shows the efficiency of the method.

关键词： Aeroacoustics scattering of sound in flows Galbrun equation advection equation finite elements discontinuous Galerkin method