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Measurement of Density Inhomogeneity for Glass Pendulum

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Chinese physics Letters 2008年第12期25卷 4203-4206页

作者：刘琳霞刘祺邵成刚张雅婷罗俊 Vadim Milyukov Department of physics Huazhong University of Science and Technology Wuhan 430074 Sternberg Astronomical institute Moscow State University Moscow 119992 Russia

The density inhomogeneity of a glass pendulum is determined by an optical interference method. The relative variations of the densities over a volume with sizes of 5 × 5×5 mm^3 are （0.64 ± 0.97） × 10^-5 and （0.99 ± 0.92） × 10^-5 for the K9 glass and silica glass pendulum, respectively. These variations of densities contributing to the relative uncertainties of the Newtonian gravitational constant G are 0.20 ppm and 0.21 ppm in our experiment on measurement of G.

关键词： field emission molybdenum dioxide enhancement factor

Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 MeV

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Chinese physics C 2024年第2期48卷 91-103页

作者： F.A.Rasulova N.V.Aksenov S.I.Alekseev R.A.Aliev S.S.Belyshev I.Chuprakov N.Yu.Fursova A.S.Madumarov J.H.Khushvaktov A.A.Kuznetsov B.S.Yuldashev Joint institute for Nuclear Research DubnaRussia institute of Nuclear physics of the Academy of Sciences of the Republic of Uzbekistan TashkentUzbekistan Faculty of Chemistry of Lomonosov moscow State university MoscowRussia national Research Center"Kurchatov institute" MoscowRussia Skobeltsyn institute of Nuclear physics of Lomonosov moscow State university MoscowRussia Faculty of physics of Lomonosov moscow State university MoscowRussia institute of Nuclear physics AlmatyRepublic of Kazakhstan

In this study,experiments were performed at bremsstrahlung end-point energies of 10-23 MeV with the beam from the MT-25 microtron using theγ-activation *** experimental values of relative yields were compared with theoretical results obtained on the basis of TALYS with the standard parameters and the combined model of photonucleon *** isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 ***,taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

关键词： bremsstrahlung photon cross section isospin splitting giant dipole resonance

Influence of Zr and Mn additions on microstructure and properties of Mg-2.5wt%Cu-Xwt%Zn(X=2.5,5 and 6.5)alloys

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1733-1745页

作者： A.V.Koltygin V.E.Bazhenov I.V.Plisetskaya V.A.Bautin A.I.Bazlov N.Y.Tabachkova O.O.Voropaeva A.A.Komissarov V.D.Belov Foundry Department National University of Science and Technology(MISiS)Moscow 119049Russia Department of Metallurgy Steel New Production Technologies and Protection of MetalsNational University of Science and Technology(MISiS)Moscow 119049Russia Laboratory of Advanced Green Materials National University of Science and Technology(MISiS)Moscow 119049Russia Department of Materials Science of Semiconductors and Dielectrics National University of Science and Technology(MISiS)Moscow 119049Russia Fianit Laboratory(Laser Materials and technology Research Center at GPI) Prokhorov General Physics Institute RASMoscow 119991Russia Laboratory of Hybrid Nanostructured Materials National University of Science and Technology(MISiS)Moscow 119049Russia Laboratory of Medical Bioresorption and Bioresistance Moscow State University of Medicine and DentistryMoscow 127473Russia

This work studied the effects of adding Zr and Mn in amounts less than 1wt%on the microstructure,mechanical properties,casting properties,and corrosion resistance of Mg-Zn-Cu alloys containing 2.5wt%Cu and 2.5wt%-6.5wt%*** hardness and electrical conductivity measurements were used to find an optimal heat treatment schedule with the best mechanical *** has been established that Zr significantly increases the yield strength of the alloys due to a strong grain refinement ***,the presence of Mn and Zr has a detrimental effect on alloy’s elongation at *** was shown that the precipitation of the Mg_(2)Cu cathodic phase in the alloy structure negatively affects the corrosion ***,the addition of Mn decreases the corrosion rate of the investigated *** best combination of the mechanical,casting,and corrosion properties were achieved in the alloys containing 2.5wt%Cu and 5wt%***,the Mn or Zr addition can improve the properties of the alloys;for example,the addition of Mn or Zr increases the fluidity of the alloys.

关键词： magnesium alloy Mg-Zn-Cu casting alloy Mn addition Zr addition

Two-pion interferometry in heavy ion collisionsat HIRFL-CSR energy

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Chinese physics C 2008年第11期32卷 897-902页

作者：于莉莉吉日木图张卫宁霍雷张景波 Department of physics Harbin Institute of Technology School of physics and Optoelectronic technology Dalian University of Technology Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou

We examine the two-pion Hanbury-Brown-Twiss （HBT） interferometry for the particle-emitting source produced in heavy ion collisions at HIRFL-CSR energy. The source evolution is described by relativistic hydrodynamics with three kinds of equations of state for chemical equilibrium （CE）, chemical freeze-out （CFO）, and partial chemical equilibrium （PCE） models, respectively. We investigate the effects of particle decay, multiple scattering, and source collective expansion on the two-pion interferometry results. We find that the HBT radii of the evolution source for the CFO and PCE The HBT lifetime for the CFO model is smaller than those models are smaller than that for the CE model. for the PCE and CE models. The particle decay increases the HBT radius and lifetime while the source expansion decreases the HBT radius. The multiple scattering effect on the HBT results can be neglected based on our model calculations.

关键词： two-pion interferometry HIRFL-CSR energy particle decay multiple scattering

Development of lead-free multifunctional materials Bi(Co_(0.45Ti0.45Fe0.10)O3

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Progress in Natural Science:Materials International 2018年第3期28卷 308-314页

作者： Nitin Kumar Alok Shukla R.N.P.Choudhary Department of physics National Institute of Technology Mizoram Department of physics Siksha ‘O′Anusandhan University

A lead free multiferroic material,Bi(Co0.45Ti0.45Fe0.10)O3（BCTF45/10）was synthesized by a solid-state reaction route at high ***45/10 powder was prepared using appropriate raw maretials in oxide powders with methanol ***-prepared circular shaped pellets were sintered at 1053 K for 6 h to produce a compact *** structural properties and elemental analysis were determined using X-ray diffraction and energy-dispersive X-ray spectroscopy techniques respectively at room *** microstructure or surface morphology of the sintered sample was carried out by using field emission scanning electron microscope（FE-SEM）.The XRD analysis shows that the compound exhibits the single-phase of orthorhombic *** average crystallite size estimated using the Scherrer's technique was found to be 30 *** influence of Co and Ti substitution（at Bi and Ti sites of Bi Fe O3）on some physical and electrical properties of Bi Fe O3was examined by using phase sensitive multimeter in a wide frequency and temperature *** magnetic nature of the sample was studied using vibrating sample *** of room temperature magnetic hysteresis loop exhibits the enhanced ferromagnetic characteristic with saturation magnetization of 5.091 emu/g and coercive field of 0.213 k Oe *** enhanced magnetic properties highlight various potential applications of Co/Ti doped BCTF45/10 materials.

关键词： Multifunctional material Dielectric constant and loss Electrical characteristics Impedance spectroscopy

Primordial black holes

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Research in Astronomy and Astrophysics 2010年第6期10卷 495-528页

作者： Maxim Yu.Khlopov Centre for Cosmoparticle physics "Cosmion " national Research Nuclear university "moscow Engineering physics institute " APC laboratory 10

Primordial black holes （PBHs） are a profound signature of primordial cosmological structures and provide a theoretical tool to study nontrivial physics of the early Universe. The mechanisms of PBH formation are discussed and observational constraints on the PBH spectrum, or effects of PBH evaporation, are shown to restrict a wide range of particle physics models, predicting an enhancement of the ultraviolet part of the spectrum of density perturbations, early dust-like stages, first order phase transitions and stages of superheavy metastable particle dominance in the early Universe. The mechanism of closed wall contraction can lead, in the inflationary Universe, to a new approach to galaxy formation, involving primordial clouds of massive BHs created around the intermediate mass or supermassive BH and playing the role of galactic seeds.

关键词： cosmology: theory -- elementary particles -- black hole physics -- dark matter -- early universe

Effects of Three Typical Resistivity Models on Pulsed Inductive Plasma Acceleration Modeling

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Chinese physics Letters 2017年第12期34卷 46-50页

作者：孙新锋贾艳辉张天平吴宸辰温晓东郭宁金海柯于俊郭伟龙 national Key Laboratory of Science and technology on Vacuum technology and physics Lanzhou Institute of Physics College of Electrical and Information Engineering Lanzhou University of Technology

The effects of three different typical resistivity models（Spitzer, Z＆L and M＆G） on the performance of pulsed inductive acceleration plasma are studied. Numerical results show that their influences decrease with the increase of the plasma temperature. The significant discriminations among them appear at the plasma temperature lower than 2.5 eV, and the maximum gap of the pulsed inductive plasma accelerated efficiency is approximately 2.5%.Moreover, the pulsed inductive plasma accelerated efficiency is absolutely related to the dynamic impedance parameters, such as voltage, inductance, capacitance and flow rate. However, the distribution of the efficiency as a function of plasma temperature with three resistivity models has nothing to do with the dynamic impedance parameter.

关键词： In Effects of Three Typical Resistivity Models on Pulsed Inductive Plasma Acceleration Modeling

Optical conductivity as a probe of a hidden Fermi-liquid behavior in BaFe_(1.904) Ni_(0.096) As_2

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Chinese physics B 2014年第10期23卷 499-502页

作者：杨彦兴熊锐方之颢许兵肖宏邱祥冈石兢王凯 School of physics and technology Wuhan University Beijing national Laboratory for Condensed Matter physics National Laboratory for Superconductivity Institute of Physics Chinese Academy of Sciences

We measured the infrared reflectivity of BaFe1.904Ni0.096As2 single crystal from room temperature down to 20 K. Two Drude terms and a Lorentz term well describe the real part of the optical conductivity σ1 （ω）. We fit the reciprocal of static optical conductivity 1/σ1（0） by the power law ρ （T）=ρo＋ATn with n= 1.6. The ＂broad＂ Drude component exhibits an incoherent background with a T-independent scattering rate 1/τb, while the other ＂narrow＂ one reveals a T-quadratic scattering rate 1/τn, indicating a hidden Fermi-liquid behavior in BaFe1.904Nio.096As2 compound.

关键词： iron-based superconductor Fermi liquid optical conductivity

Entropy and equilibrium property of QCD-instanton induced final state in deep-inelastic scattering

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Chinese physics C 2008年第1期32卷 13-17页

作者：邓为炳陆丁张纪英许明梅 Boris Levchenko 刘连寿 Training Base for Research and Teaching in Fundamental Sciences(physics)College of Physical Science and technology Huazhong Normal university institute of Particle physics Huazhong Normal university Skobeltsyn institute of Nuclear physics moscow State university 119992 MoscowRussia

The scaling and additivity properties of Rényi entropy in rapidity space of the instanton final state （IFS） and current jet identified by the r-sorting method from the QCDINS Monte Carlo event sample are studied. Asymptotic scaling of the Rényi entropy H2 is observed for the IFS while H2 for the current jet jtends to saturation with decreasing phase space scale. Furthermore, it is found that the additivity of H2 holds well for the IFS in narrow rapidity windows at different positions. These results indicate that the IFS produced in the instanton-induced process of deep inelastic scattering has reached local equilibrium.

关键词： instanton quark-gluon fusion deep-inelastic scattering entropy local equilibrium