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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

On the detection of closed orbits in time-dependent systems by using double-pulse lasers

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Communications in Theoretical Physics 2020年第9期72卷 111-117页

作者： S u Khan M l Du Institute of Theoretical Physics Chinese Academy of Sciences.Beijing 100190China university of Chinese Academy of Sciences Beijing100049China

In the photodetachment of atoms or negative ions by a double-pulse laser, the first pulse of the double-pulse laser generates waves and the delayed second pulse may detect them. The phenomenon of the excitation and detection of waves by a double-pulse laser can be used to identify the closed orbits in the system. We demonstrate this phenomenon with a negative hydrogen ion(h^-) by analyzing the total population excited by a double-pulse laser in a timedependent field for different physical parameters. By analyzing the total excited population using a double-pulse laser, we can uncover all the closed orbits existing in the system. We demonstrate that this can be realized by scanning the first pulse position and the time delay between the two pulses.

关键词： double-pulse laser detection of closed orbits photodetachment spectra time-dependent systems

Effects of an Intense laser field and hydrostatic Pressure on the Intersubband Transitions and Binding Energy of Shallow Donor Impurities in a Quantum Well

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Chinese Physics letters 2011年第7期28卷 254-257页

作者： u.Yesilgul f.ungan E.Kasapoglu h.Sari I.Sökmen Department of Physics Cumhuriyet University58140 SivasTurkey Department of Physics Dokuz Eylül University35160 IzmirTurkey

We have calculated the intersubband transitions and the ground-state binding energies of a hydrogenic donor impurity in a quantum well in the presence of a high-frequency laser field and hydrostatic *** calculations are performed within the effective mass approximation,using a variational *** conclude that the laser field amplitude and the hydrostatic pressure provide an important effect on the electronic and optical properties of the quantum *** to the results obtained from the present work,it is deduced that(i)the binding energies of donor impurity decrease as the laser field increase,(ii)the binding energies of donor impurity increase as the hydrostatic pressure increase,(iii)the intersubband absorption coefficients shift toward lower energies as the hydrostatic pressure increases,(iv)the magnitude of absorption coefficients decrease and also shift toward higher energies as the laser field *** is hopeful that the obtained results will provide important improvements in device applications.

关键词： method hydrostatic donor

Spectrophotometric determination of tranexamic acid using vanillin

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药学学报 2009年第2期44卷 175-180页

作者： f.M.A. Rind M.G.h. laghari A.h. Memon u.R. Mughal E Almani N. Memon M.Y. Khuhawar M.l. Maheshwari faculty of Pharmacy University of Sindh Jamshoro Pakistan Institute of Chemistry Faculty of Natural Sciences University of Sindh Jamshoro Pakistan

A new spectrophotometric method has been examined for the determination of the tranexamic acid (TA) by derivatization with vanillin (VAN). The molar absorptivity of TA was calculated 25 160 l·mol-1·cm-1 at λmax 354 nm and obeyed the Beer's law within 0.5-2.5 μg·ml-1. The color reaction was highly stable and did not show any change in absorbance up to 24 h. The method was applied for the analysis of TA from capsules, injections and tooth pastes. The amounts of TA found in capsules, injections and tooth pastes of various pharmaceutical companies were observed with 249.0-250.9 mg/capsule, 249.3-250.7 mg/injection and 0.048%-0.049% in tooth pastes with relative standard deviation (RSD) 0.2%-5.0% (n = 3).

关键词：分光方法氨甲环酸显色反应药物化学

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： u.S.Mahabaleshwar G.P.Vanitha l.M.Pérez Emad h.Aly I.Pop Department of Studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de f´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in h_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/h_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/h_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

A carbuncle cure for the harten-lax-van leer contact(hllC)scheme using a novel velocity-based sensor

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1259-1278页

作者： u.S.VEVEK B.ZANG T.h.NEW Department of Mechanical Materials and Aerospace EngineeringUniversity of LiverpoolLiverpool L693BXUnited Kingdom Department of Aerospace Engineering University of BristolBristol BS81TRUnited Kindgdom School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

A hybrid numerical flux scheme is proposed by adapting the carbunclefree modified harten-lax-van leer contact(hllCM) scheme to smoothly revert to the harten-lax-van leer contact(hllC) scheme in regions of shear. This hybrid scheme, referred to as the hllCT scheme, employs a novel, velocity-based shear sensor. In contrast to the non-local pressure-based shock sensors often used in carbuncle cures, the proposed shear sensor can be computed in a localized manner meaning that the hllCT scheme can be easily introduced into existing codes without having to implement additional data structures. Through numerical experiments, it is shown that the hllCT scheme is able to resolve shear layers accurately without succumbing to the shock instability.

关键词： carbuncle shock instability Euler equation numerical flux harten-laxvan leer contact(hllC)scheme

Macrophages in immunoregulation and therapeutics

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Signal Transduction and Targeted Therapy 2023年第6期8卷 I0002-I0002,2821-2854页

作者： Shanze Chen Abdullah f.u.h.Saeed Quan liu Qiong Jiang haizhao Xu Gary Guishan Xiao lang Rao Yanhong Duo Department of Respiratory Diseases and Critic Care unit Shenzhen Institute of Respiratory DiseaseShenzhen Key Laboratory of Respiratory DiseaseShenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen518020China Department of Cancer Biology Beckman Research Institute of City of Hope National Medical CenterLos AngelesCA91010USA Department of laboratory Medicine Huazhong University of Science and Technology Union Shenzhen Hospital(Nanshan Hospital)Shenzhen UniversityShenzhen518052China Department of Respiratory The First Affiliated HospitalSchool of MedicineSouthern University of Science and TechnologyShenzhen518055China State Key laboratory of fine Chemicals Department of Pharmaceutical SciencesSchool of Chemical EngineeringDalian University of TechnologyDalianChina Institute of Biomedical health Technology and Engineering Shenzhen Bay LaboratoryShenzhen518132China Department of Microbiology Tumor and Cell Biology(MTC)Karolinska InstitutetStockholmSweden

Macrophages exist in various tissues,several body cavities,and around mucosal surfaces and are a vital part of the innate immune system for host defense against many pathogens and *** possess binary M1/M2 macrophage polarization settings,which perform a central role in an array of immune tasks via intrinsic signal cascades and,therefore,must be precisely *** crucial questions about macrophage signaling and immune modulation are yet to be *** addition,the clinical importance of tumor-associated macrophages is becoming more widely recognized as significant progress has been made in understanding their ***,they are an integral part of the tumor microenvironment,playing a part in the regulation of a wide variety of processes including angiogenesis,extracellular matrix transformation,cancer cell proliferation,metastasis,immunosuppression,and resistance to chemotherapeutic and checkpoint blockade ***,we discuss immune regulation in macrophage polarization and signaling,mechanical stresses and modulation,metabolic signaling pathways,mitochondrial and transcriptional,and epigenetic ***,we have broadly extended the understanding of macrophages in extracellular traps and the essential roles of autophagy and aging in regulating macrophage ***,we discussed recent advances in macrophages-mediated immune regulation of autoimmune diseases and ***,we discussed targeted macrophage therapy to portray prospective targets for therapeutic strategies in health and diseases.

关键词： becoming polarization Macrophages

会聚束电子衍射研究蠕变镍基高温合金中γ和γ’相的局域应变分布

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金属学报 2006年第7期42卷 694-698页

作者：吕铮 f.Pyczak h.Biermann h.Mughrabi Institut für Werkstoffwissenschaften lehrstuhl I Universitt Erlangen-Nürnberg91058 ErlangenGermany

用高分辨率会聚束电子衍射方法(CBED)测量了单晶镍基高温合金CMSX-6在980℃蠕变后γ和γ’两相中的弹性应变分布．测量表明在水平和垂直的γ通道中存在着弹性应变的差别,这种差别被认为是筏化的驱动力．在γ’相中还观察到弹性应变的不... 详细信息

用高分辨率会聚束电子衍射方法(CBED)测量了单晶镍基高温合金CMSX-6在980℃蠕变后γ和γ’两相中的弹性应变分布．测量表明在水平和垂直的γ通道中存在着弹性应变的差别,这种差别被认为是筏化的驱动力．在γ’相中还观察到弹性应变的不均匀分布．

关键词：会聚束电子衍射镍基高温合金应变

The surface pollen and relative pollen production of the desert vegetation of the Alashan Plateau, western Inner Mongolia

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Chinese Science Bulletin 2003年第14期48卷 1488-1493页

作者： u.herzschuh h.Kuerschner MAYuzhen InstituteofPlantSystematicsandGeobotany FreeUniversityofBer-lin.Germanw DepartmentofGeography LanzhouUniversityLanzhou730000China

This preliminary investigation focuses on the comparison of the recent pollen precipitation and its related vegetation of eight different plant communities in the Alashan Region, the most western part of the Inner Mongolia Autonomous Region. Most zonal and azonal communities can be well identified by their pollen spectra. Relative pollen production factors of various plant taxa have been calculated and the following sequences from over- to under represented taxa have been found for zonal vegetation: Chenopodiaceae, Artemisia, Ephedra, Nitraria, Reaumuria, Calligonum, Zygophyllum; and for azonal vegetation: Peganum, Populus, Tamarix, lycium.

关键词：内蒙古西部沙漠植被花粉植物分布植物群落地带性植被