聚丙烯(PP)/纳米SiO_2复合材料的流变行为、力学性能和相态学研究

以毛细管流变仪研究了PP/纳米SiO2复合材料熔体的流变行为,讨论了复合材料的组成、剪切应力和剪切速率对熔体流变行为、熔体粘度的影响,测定了熔体的非牛顿指数、熔体流动速率和膨胀比。结果表明:PP/纳米SiO2复合材料属假塑性流体,其熔体粘度随纳米SiO2含量的增加而增大,非牛顿指数和熔体流动速率均随纳米SiO2含量的增加而减小;在恒定剪切应力下,膨胀比随纳米SiO2含量的增加而减小。对复合材料的力学性能测试结果表明:纳米SiO2对PP的力学性能有显著改善作用。以扫描电镜和偏光显微镜研究了复合材料的相态学,其结果进一步证明了纳米SiO2对PP具有增强增韧作用。

论群学相态

群学在战国末期诞生以后是否得以传承,其传承机制和绵延形式是什么,个中原委极为复杂,从“经世致用”可以找到正确答案。“经世致用”还影响到学术的存在和绵延形式。基于对荀子及其门生和后学影响、参与秦汉制度建设的历史过程的分析,考察由此开启的群学从元典向制度化、民间化、心性化和转型的“相态”演进脉络。从历史实践、社会理论和思维逻辑三个层次揭示了群学相态演进的实现机制,从而进一步证明群学的历史存在性和绵延性。基于此,可以揭示群学的存在形式何以与西方社会学不同的原因,如何看待中西学科分化模式之异同,既是方法论问题,也是价值选择问题。

Bi-modal microstructure in a powder metallurgical ferritic steel

Ferritic steel with a nominal composition of Fe-14Cr-3W-0.42Ti-0.32Y was prepared by mixing gas-atomized prealloyed powder and mechanically alloyed powder. The microstructure is much different fxom other ferritic steels with the same composition and prepared via only mechanically alloyed powder. A bi-modal structure, which consists of pure ferritic grains and martensitic grains, was obtained after hot forging and air cooling. A phase transformation of αbcc→γfcc→α＇bcc was also discovered in microstructural observation. The bi-modal microstructure shows a good combination of high strength and high ductility.

STUDY ON THE MORPHOLOGY OF LIPS AND ASSOCIATED STRUCTURES IN THE CYPRINID GENUS Parasinilabeo

The comparative morphology of the lips and associated structures is studied among Parasinilabeo and its taxonomically related groups. On the basis of the morphological features of the lips and associated structures, Parasinilabeo is proposed to be closely associated with Pseudogyrinocheilus and Semilabeo ;and four typical mouth patterns are identifled among Parasinilabeo and its taxonomically related groups.

Isolation and Identification of a Taxol-producing Endophytic Fungus Identified from Taxus media

[Objective] The aim was to isolate and identify a taxol-producing endophytic fungus from Taxus media. [Method] 32 strains of endophytic fungi were identified form the inner bark of T. media,and their fermentation products were detected by high performance liquid chromatography (HPLC). [Result] Through the screening,a strain of taxol-producing endophytic fungi M57 was obtained,which could produce 45-50 μg/L of taxol,and M57 was defined as Rhizopus sp. through morphological observation and 18S rDNA sequence analysis. [Conclusion] The finding of Rhizopus sp. M57 provided a promising strain for producing taxol with taxol-producing fungi fermentation process.

Influence of I-phase and W-phase on microstructure and mechanical properties of Mg-8Li-3Zn alloy

Microstructures and mechanical properties of LZ83?xY alloys containingI-phase andW-phase were investigated by XRD, OM, SEM and EDS. The experimental results show that the content ofI-phase andW-phase changes by varying Zn/Y mass ratio in the LZ83?xY alloys. The cohesion ofI-phase/α-Mg eutectic pockets can enhance the strength in the as-cast LZ83?0.5Y and LZ83?1.0Y alloys, while theW-phase has no obvious strengthening effect on the LZ83?1.5Y alloy. In the extruded alloys, the I-phase andW-phase were extruded into the particles with nanoscale size in theβ-Li matrix phase. The dispersion strengthening of W-phase was more obvious because of the higher volume fraction. The ultimate tensile strength of extruded LZ83?1.5Y alloy is up to 238 MPa while the elongation is up to 20%.

Morphological parameters of both surfaces of coupled joint

Twenty one joints were made with Brazilian tests and each surface was scanned by the Talysurf CLI 2000. Morphological characteristics of joint surface were quantified by statistical and textural parameters. By the contrast of these parameters between both sides of each coupled joint, the following conclusions are drawn. The upper and lower surfaces of coupled joints have approximately equal values of Sp（maximum height of joint surface）, Sa（arithmetic mean height of joint surface） and Sq（root mean square height of joint surface）, but the Ssk（skewness of the height distribution of joint surface） values of the two surfaces of a coupled joint are different, one is positive while the other is negative. The Saj（auto-correlation length） parameter values of both surfaces of each coupled joint are quite close, and the S^（texture aspect ratio） values have the same situation to the Sal parameter, but the same parameters of different surfaces have big differences which illustrates its own characteristics of each joint. The two surfaces of each coupled joint have similar values of θp （mean profile angle） which can be used to deduce the value of θp each other.

Generalized Bargmann Representation of Spin Coherent State

Based on the conclusion that the generalized Bargmann representation of a two-mode Fock state is a two-variable Hermite polynomial function /Hong-Yi Fan and Jun-hua Chen,Phys.Lett.A303(2002)311] we derive the generalized Bargmann representation of the spin coherent state and some new relations in the generalized function space.

Dynamics of Jaynes-Cummings Model in the Absence of Rotating-Wave Approximation

The Jaynes-Cummings model （JCM） is studied in the absence of the rotating-wave approximation （RWA） by a coherent-state expansion technique. In comparison with the previous paper in which the coherent-state expansion was performed only to the third order, we carry out in this paper a complete expansion to demonstrate exactly the dynamics of the JCM without the RWA. Our study gives a systematic method to solve the non-RWA problem, which would be useful in various physical systems, e.g., in a system with an ultracold trapped ion experiencing the running waves of lasers.

Heisenberg Model in a Rotating Magnetic Field

We study the Hcisenberg moder under the influence of a rotating magnetic field. By using a time- dependent unitary transformation, the time evolution operator for the Schrodinger equation is obtained, which involves no chronological product. The spin vectors (mean values of the spin operators) are obtained as explicit functions of time in the most general case. A series of cyclic solutions are presented. The nonadiabatic geometric phases of these cyclic solutions are caleulated, and are expressed in terms of the solid angle subtended by the closed trace of thc total spin vector, as well as in terms of those of the individual spins.

Critical Spreading of Active Region in a Ladder Model Possessing Infinite AbsorbingStates

The spreading of active region of the ladder model is simulated. Finite-time scaling behaviors are observedin the vicinity of the critical point.

Properties of Coherent State for Hydrogen Atom

We construct the coherent state for the two-dimensional hydrogen atom,for which the averaged motion of position describes a Kepler ellipse.The coherent state can be expanded with respect to the eigenstates of 2D hydrogen atom,from which we evaluate the binding energy of the wave packet for this state.

Entanglement of Non-symmetric Two Atomic Qubits Induced by a Coherent State Field

The entanglement of two atomic qubits, which are coupled to a coherent state field with different couplings, is studied. The dynamical evolution of the concurrence, which measures the degree of the entanglement between the two qubits, is plotted versus the scaled time gt. It is found that the two qubits can be entangled by the coherent state field even when they are initially prepared in the most mixed state, and for very weak field, the most mixed state can be; more easily entangled than some pure states. It is also found that the entanglement between the qubits sensitively depends on the relative difference of the atomic couplings and the mean photon number of the field.

Teleportation of Unknown Superpositions of Collective Atomic Coherent States

We propose a scheme to teleport an unknown superposition of two atomic coherent states with different phases. Our scheme is based on resonant and dispersive atom-field interaction. Our scheme provides a possibility of teleporting macroscopic superposition states of many atoms first time.

Phase Properties of Nonlinear Coherent States

Using the Pegg-Barnett formalism we study the phase probability distributions and the squeezing effects of measured phase operators in the nonlinear coherent states introduced by R.L. de Matos Filho and W. Vogel to describe the center-of mass motion of a trapped ion and the q-coherent states. Moreover, we have obtained the completeness relation of nonlinear coherent states and proved that the q-Fock state \n>(q) introduced in many papers is, in fact, the usual Fock state.

Charaterization of Citrus Hybrid ＂Huangguogan＂ through the Combination of Morphological and Molecular Markers

Huangguogan, an obvious Citrus hybrid, is suitable for transportation and export and ripens in March or April. Because of late season, it may playa significant role in fruit market. However, its origin is still unconfirmed. The aim of this study was to clarify the possible parentage of Huangguogan via the combination of morphological and molecular markers including simple sequence repeat （SSR） and chloroplast simple sequence repeat （cpSSR）. Analysis of morphological traits including leaf stalk length, phylliform index and fruit shape index indicated that Huangguogan had similarities in morphology with Sweet orange. The SSR Cluster Analysis showed that Huangguogan was clustered together with Hongju tangerine and revealed -80% genetic similarity. They illustrated a close genetic distance between Huangguogan and Hongju tangerine. In addition, the bands of2 polymorphic cpSSR were identical in Huangguoggan and Sweet orange. Consequently, it is likely that its female parentage was the sweet orange （Citrus sinensis （L.） Osbeck） and its male parentage was the tangerine （Citrus reticulata Blanco）.

Modeling VLE and GLE of Systems Involving Polymers by Using SRK Equation of State

A simple extension of cubic equations of state(EOS)to polymer systems has been proposed.The So-ave-Redlich-Kwong(SRK)EOS was taken as a prototype to be used to describe the PVT behavior of polymer melts in a wide temperature and pressure range.Combined with a modified Huron-Vidal gE-mixing rule it was applied for modeling vapor-liquid equilibria of polymer-solvent solutions and the solubility of supercritical gases in polymer melts.Satisfactory results are obtained.

Statistical Properties of the nonlinear SU（1,1） Coherent States

Using non-Hermitian realizations of SU(1,1) Lie algebra in terms of an f-oscillator, we generalize the notion of nonlinear coherent states to the single-mode and two-mode nonlinear SU(1,1) coherent states. Taking the nonlinearity function , their statistical properties are studied.

Amplitude-Nth-power squeezing of PB phase coherent states

PB Phase Coherent States are very important quantum states in quantum optics. In order to investigate the amplitude-Nth-power squeezing of PB Phase Coherent States, we introduce the algebraic properties of the PB phase operator and the PB Phase Coherent States which are constructed by PB phase theory. We applied amplitude-Nth-power squeezing theory to define the Amplitude-Nth-Power Squeezing of PB Phase Coherent States and investigate the characteristic of the amplitude-Nth-power squeezing of PB Phase Coherent States. We obtained surprising results, in that the results were different from the other quantum states. As for |Z〉(PB Phase Coherent State), the results show that when Z is a real number there only exists amplitude-Nth-power squeezing of component; when Z is a complex number, there exists amplitude-Nth-power squeezing of component and component; when Z is a pure imaginary number, if N is odd, then there does not exist amplitude-Nth-power squeezing of component, but there exists amplitude-Nth-power squeezing of component and if N is even, then there exists amplitude-Nth-power squeezing of component, but there does not exist amplitude-Nth-power squeezing of component.

Remark on Relations Between Different Non-integrable Phases

There are three non-integrable phases in literatures: Berry phase, Aharonov-Anandan phase, and Yang phase. This article discusses the definitions and relations between these three non-integrable phases.