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Effect of Phase Noise on the Stationary Entanglement of an Optomechanical System with Kerr Medium

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Chinese Physics Letters 2013年第2期30卷 143-146页

作者： ZHANG Dan zheng qiang School of Chemistry and Material Science Guizhou Normal UniversityGuiyang 550001 School of Mathematics and Computer Science Guizhou Normal UniversityGuiyang 550001

We theoretically investigate the effect of phase noise on the stationary entanglement of an optomechanical system,which has the additional Kerr medium in the *** are two kinds of interactions in the system,photon-mirror interaction and photon-photon *** find that the optomechanical entanglement can be suppressed by the phase noise of the pumping laser and Kerr interaction of *** also find that Kerr interaction can make the phase-noise-induced double peak of the stationary entanglement change to a single peak.

关键词： interaction. stationary interaction

Dynamics of Bose-Einstein condensates in a one-dimensional optical lattice with double-well potential

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Frontiers of physics 2013年第4期8卷 375-380页

作者： Han-Lei zheng qiang Gu Department of Physics University of Science and Technology Beijing Beijing 100083 China

We study dynamical behaviors of the weakly interacting Bose-Einstein condensate in the one- dimensional optical lattice with an overall double-well potential by solving the time-dependent Gross-Pitaevskii equation. It is observed that the double-well potential dominates the dynamics of such a system even if the lattice depth is several times larger than the height of the double-well potential. This result suggests that the condensate flows without resistance in the periodic lattice just like the case of a single particle moving in periodic potentials. Nevertheless, the effective mass of atoms is increased, which can be experimentally verified since it is connected to the Josephson oscillation frequency. Moreover, the periodic lattice enhances the nonlinearity of the double-well condensate, making the condensate more ＂self-trapped＂ in the ^-mode self-trapping regime.

关键词： Bose-Einstein condensate double-well potential optical lattice dynamical behavior

Approaching Quantum-Limited Amplification with Large Gain Catalyzed by Optical Parametric Amplifier Medium

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Communications in Theoretical Physics 2017年第7期67卷 76-82页

作者： qiang zheng Kai Li School of Mathematics Guizhou Normal University Guiyang 550025 China Beijing Computational Science Research Center Beijing 100193 China

Amplifier is at the heart of experiments carrying out the precise measurement of a weak signal. An idea quantum amplifier should have a large gain and minimum added noise simultaneously. Here, we consider the quantum measurement properties of the cavity with the OPA medium in the op-amp mode to amplify an input signal. We show that our nonlinear-cavity quantum amplifier has large gain in the single-value stable regime and achieves quantum limit unconditionally.

关键词： amplifier op-amp mode OPA quantum limit

l^(2) Decoupling for Certain Surfaces of Finite Type in R^(3)

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1442-1458页

作者： Zhuo Ran LI Ji qiang zheng School of Mathematics and Statistics Yancheng Teachers UniversityYancheng 224002P.R.China Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088P.R.China

In this article,we establish an 2 decoupling inequality for the surface F_(4)^(2):={(ξ1,ξ2,ξ_(1)^(4)+ξ_(2)^(4)):(ξ1,ξ2)∈[0,1]^(2)}associated with the decomposition adapted to finite type geometry from our previous work[Li,Z.,Miao,C.,zheng,J.:A restriction estimate for a certain surface of finite type in R^(3).*** ***.,27(4),Paper No.63,24 pp.(2021)].The key ingredients of the proof include the so-called generalized rescaling technique,an l^(2) decoupling inequality for the surfaces{(ξ1,ξ2,φ1(ξ1)+ξ42):(ξ1,ξ2)∈[0,1]^(2)}with φ1 being non-degenerate,reduction of dimension arguments and induction on scales.

关键词： Decoupling inequality finite type reduction of dimension arguments induction on scales

Exact Confidence Limits for the Parameter of an Exponential Distribution in the Accelerated Life Tests under Type-ⅠCensoring

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Acta Mathematicae Applicatae Sinica 2021年第2期37卷 393-408页

作者： De-qiang zheng Xiang-zhong FANG School of Mathematical Sciences Peking UniversityBejing 100871China

Life data frequently arise in many reliability studies,such as accelerated life tests *** paper considers the part of life data where failure and censoring observations may *** develop statistical methods and theory for the analysis of these data,a new approach was proposed to obtain the exact lower and upper confidence limits for the mean life of the exponential distribution with Type-I censoring *** is assumed that the acceleration factor is a random variable,and that the distribution of the acceleration factor is known from some empirical information or the meta analysis.A method for constructing the lower and upper confidence limits for the parameter based on an ordering relation among the sample space was *** studies and analyses of two examples suggest that the proposed method performed well.

关键词： mean life confidence limit acceleration factor sample space ordering relation

Rheological Behavior of the Melts for Polyethylene-based Montmorillonite Nanocomposites

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Chemical Research in Chinese Universities 2006年第5期22卷 651-657页

作者： YANG Hong-mei zheng qiang DU Miao Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 P. R. China National Engineering Research Center for Compounding and Modification of Polymer Materials Guiyang 550025 P. R. China

The viscoelastic properties of melts of nanocomposites with partially exfoliated structures, which were composed of low-density polyethylene （LDPE）, ethylene vinyl acetate copolymer （EVA）, and montmofillonite and modified by cetyltrimethyl ammonium bromide and octadecyltrimethyl ammonium bromide, were studied. The results obtained through measurements of the dynamic storage modulus G′, the dynamic loss modulus G″, and the transiem stress relaxation modulus G（t） of the composites, reveal that the viscoelastic properties of the composites strongly depend on the amount of montmorillonite that is exfoliated into the composites. With the increase in montmoriUonite content, the composites show an obvious property of pseudo solid-like materials within the region of lower frequencies （ω）. The montmorillonite layers are aligned along the stress direction, and the dependence of dynamic modulus on ω, appears quite different for the composites before and after being exposed to a large amplitude oscillatory shears.

关键词： Rheological behavior Nanocomposite Polyethylene Montmorillonite

DISPERSION STABILITY AND RHEOLOGICAL BEHAVIOR OF SUSPENSIONS OF POLYSTYRENE COATED FUMED SILICA PARTICLES IN POLYSTYRENE SOLUTIONS

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Chinese Journal of Polymer Science 2012年第1期30卷 26-35页

作者： Xian-ze Yin Ye-qiang Tan Yi-hu Song qiang zheng Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education Zhejiang University Hangzhou 310027 China Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Polystyrene coated silica（SiO_2@PS） core-shell composite particles with averaged diameter of about 290 nm were prepared by in situ emulsion polymerization of styrene on the surface ofγ-methacryloxypropyltrimethoxysilane grafted SiO_2 nanoparticles of 20-50 nm in *** behavior and dispersion stability of SiO_2@PS suspension in 10 wt%PS solution were compared with suspensions of untreated SiO_2 and silane modified SiO_2 *** of the untreated and the silane modified SiO_2 exhibited obvious shear *** SiO-2@PS suspension exhibits shear viscosity considerably smaller than suspensions of untreated and silane modified SiO_2 at low shear *** electron microscopy showed that the composite particles can uniformly and stably disperse in PS solution compared to other suspensions,implying that the PS shell can effectively enhance the particle compatibility with PS macromolecules in solution.

关键词： Fumed SiO_2 Polystyrene Composite particles Suspension Steady rheology

Iron recovery and rare earths enrichment from Bayan Obo tailings using Coal-Ca(OH)2-NaOH roasting followed by magnetic separation

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Journal of Iron and Steel Research International 2017年第2期24卷 147-155页

作者： qiang zheng Xue Bian Wen-yuan Wu School of Metallurgy Northeastern University Shenyang 110819 Liaoning China

The recovery of iron and enrichment of rare earths from Bayan Obo railings were investigated using Coal Ca（OH） 2 NaOH roasting followed by magnetic separation. The influences of roasting temperature, roasting time, coal content, milling time, Ca（OH）2 dosage and NaOH dosage on the iron and rare earths recovery were explored. The results showed that the magnetic concentrate containing 70.01 wt. % Fe with the iron recovery of 94.34G and the tailings of magnetic separation containing 11.46 wt. % rare earth oxides （REO） with the REO recovery of 98. 19% were obtained under the optimum conditions （i. e. , roasting temperature of 650℃, roasting time of 60 min, coal content of 2.0%, milling time of 5 min, and NaOH dosage of 2.0%）. The Ca（OH）2 dosage had no effect on the separation of iron and rare earths. According to the mineralogical and morphologic analysis, the iron and rare earths of Bayan Obo tailings could be utilized in subsequent ironmaking process and hydrometallurgy process.

关键词： Bayan Obo tailing Iron recovery Rare earth enrichment Roasting Magnetic separation

Influence of Liquid Isoprene Rubber on Strain Softening of Carbon Black Filled Isoprene Rubber Nanocomposites

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Chinese Journal of Polymer Science 2021年第7期39卷 887-895页

作者： Feng-Yi Hou Yi-Hu Song qiang zheng MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

The reinforcement of rubbers by nanoparticles is always accompanied with enhanced dissipation of mechanical energy upon large *** for solving the contradiction between improving reinforcement and reducing energy dissipation for rubber nanocomposites have not been well *** carbon black(CB)filled isoprene rubber(IR)/liquid isoprene rubber(LR)blend nanocomposites with similar crosslink density(ve)are prepared and influence of LR on the strain softening behaviors including Payne effect under large amplitude shear deformation and Mullins effect under cyclic uniaxial deformation is *** introduction of LR could improve the frequency sensitivity of loss modulus and reduce critical strain amplitude for Payne effect and loss modulus at the low ***,tuning ve and LR content allows reducing mechanical hysteresis in Mullins effect without significant impact on the mechanical *** investigation is illuminating for manufacturing nanocomposite vulcanizates with balanced mechanical hysteresis and reinforcement effect.

关键词： Rubber nanocomposites Stress softening Mechanical hysteresis Liquid rubber