Fe-C-Mn-Si低合金钢奥氏体分解的热力学/动力学相关性

热力学/动力学相关性是钢铁组织预测和加工工艺确定的必备条件,采用Gleeble热模拟机,研究未变形以及非再结晶区变形20%和40%后Fe-0.2C-1Mn-1Si(质量分数/%)低合金钢奥氏体分解中热力学/动力学相关性规律.结果表明:随冷速增大,奥氏体发生相变的热力学驱动力升高,而相变由动力学能垒较大的扩散型逐渐转变为能垒较小的切变型.非再结晶区变形提高了奥氏体分解的热力学驱动力,同时缺陷的产生降低了扩散型相变的动力学能垒.冷却路径或变形条件的改变通过热力学驱动力和动力学能垒的相关性,导致奥氏体分解中相变组织的不同.

纳米薄膜力学性能的尺寸相关性及其残余应力分析

系统地分析了纳米薄膜残余应力产生的物理机制，重点讨论了表面应力对纳米薄膜的影响，解释了纳米薄膜特殊的力学性能尺寸相关性，并通过考虑表面应力的有限元模型给出了纳米薄膜单轴拉伸的数值模拟结果。

Pharmacokinetics of two modified release system of dipyridamole in beagle dogs

A novel floating osmotic pump controlled release system （FOP） and traditional matrix sustained release tablets （MT） of dipyridamole （DIP） were characterized in terms of pharmacokinetics, drug release, and in vitro-in vivo correlation. In vivo study was performed by a three-crossover study in six beagle dogs relative to the conventional tablet （CT）. A HPLC method for the determination of DIP in the plasma was developed. Cumulative percent of absorption fraction was compared to that of in vitro cumulative release. Both FOP and MT displayed obvious extended release characteristic in vivo while FOP showed a better extended release behavior. The bioavailability of FOP was higher than that of MT and a zero-order release linear correlation of DIP between fraction absorbed in vivo and fraction dissolved in vitro was established for FOP while not for MT. The results indicated the existence of an absorption window in upper part of the GI track of DIP, which meant that floating system could be excellent for the drug delivery. In addition, the in vitro model was a good choice for depicting in vivo absorption and for optimization of the formulation of FOP if it is needed to be bio-equivalent to MT.

Interface kinetics modeling of binary alloy solidification by considering correlation between thermodynamics and kinetics

By considering collision-limited growth mode and short-range diffusion-limited growth mode simultaneously,an extended kinetic model for solid−liquid interface with varied kinetic prefactor was developed for binary alloys.Four potential correlations arising from effective kinetics coupling the two growth modes were proposed and studied by application to planar interface migration and dendritic solidification,where the linear correlation between the effective thermodynamic driving force and the effective kinetic energy barrier seems physically realistic.A better agreement between the results of free dendritic growth model and the available experiment data for Ni−0.7at.%B alloy was obtained based on correlation between the thermodynamics and kinetics.As compared to previous models assuming constant kinetic prefactor,a common phenomenon occurring at relatively low undercoolings,i.e.the interface migration slowdown,can be ascribed to both the thermodynamic and the kinetic factors.By considering universality of the correlation between the thermodynamics and kinetics,it is concluded that the correlation should be considered to model the interface kinetics in alloy solidification.

Relationship of quantitative structure and pharmacokinetics in fluoroquinolone antibacterials

AIM： To study the relationship between quantitative structure and pharmacokinetics （QSPkR） of fluorocluinolone antibacterials.METHODS： The pharmacokinetic （PK） parameters of oral fluoroquinolones were collected from the literature. These pharmacokinetic data were averaged, 19 compounds were used as the training set, and 3 served as the test set. Genetic function approximation （GFA） module of Cerius2 software was used in QSPkR analysis.RESULTS： A small volume and large polarizability and surface area of substituents at C-7 contribute to a large area under the curve （AUC） for fluoroquinolones. Large polarizability and small volume of substituents at N-1 contribute to a long half life elimination.CONCLUSION： QSPkR models can contribute to some fluoroquinolones antibacterials with excellent pharmacokinetic properties.

Influence of Carbonation on Mechanical Properties of Concrete

As one of the most important factors that determine the lifespan of a reinforced concrete structure, carbonation not only corrodes the reinforcing steel, but also changes the mechanical properties of concrete. For better understanding the performance of carbonated concrete structure, it is necessary to study the mechanical properties of carbonated concrete. The strees strain relationship of carbonated concrete was analyzed on the basis of experiments. The specimens were made by means of accelerated carbonation and then compressed on the testing machine. Some very important characteristics of carbonated concrete were revealed by the testing results. In addition, a useful constitutive model of carbonated concrete, which proved to be suitable for analyzing carbonated concrete members, was established in this research.

Pharmacokinetics of mycophenolic acid in Chinese kidney transplant patients

To assess the influence of cyclosporin A (CsA) and tacrolimus (FK506) on mycophenolic acid (MPA) and correlation analysis of the pharmacokinetic parameters and patient characteristics, clinical outcome in Chinese kidney transplant recipients, the pharmacokinetics of 1000 mg mycophenolate mofetil (MMF) twice daily was measured by high-performance liquid chro- matography (HPLC). PKS (Pharmaceutical Kinetics Software) 1.0.2 software package was used for the calculation of pharma- cokinetic parameters. The mean Cmax, tmax, and AUC(0?12)were (21.88±10.52) μg/ml, (1.20±0.95) h, and (52.546±13.215) μg·h/ml, respectively. The level of AUC(0?12) in the FK506 group was significantly higher than that in the CsA group. MPA appeared not to be affected by renal function. MPA AUC(0?12) showed statistically significant difference according to the patient’s gender.

Comparison of the morphometric dynamics of fast-growing and slow-growing strains of turbot Scophthalmus maximus

The dynamics of changes in body shape of fast-growing and slow-growing strains of turbot Scophthalmus maximus, and of the differences in body shape between the two strains, were evaluated from 3 to 27 months of age. The ratios of total length/body length, body width/body length and total length/body width were used as morphometric indices. The two strains exhibited different temporal trends in total length/body length but similar trends in body width/body length and total length/body width. Generally, body width/body length of the two strains increased with time and total length/body width decreased. Thus, the bodies of both fast-growing and slow-growing strains of turbot changed from a narrow to a more rounded shape. However, the ratio total length/body length was generally lower, body width/body length was mostly higher and total length/body width was consistently lower in the fast-growing strain than in the slowgrowing strain. Correlation analysis of the three shape ratios with body weight showed that total length/body length and total length/body width were unsuitable, and that width/body length was suitable, for use as a phenotypic marker for selective breeding of turbot for growth in weight.

Correlations in Werner States

Werner states are paradigmatic examples of quantum states and play an innovative role in quantum information theory. In investigating the correlating capability of Werner states, we find the curious phenomenon that quantum correlations, as quantified by the entanglement of formation, may exceed the total correlations, as measured by the quantum mutual information. Consequently, though the entanglement of formation is so widely used in quantifying entanglement, it cannot be interpreted as a consistent measure of quantum correlations per se if we accept the folklore that total correlations are measured （or rather upper bounded） by the quantum mutual information.

The Antiferromagnetic Correlations in the Half—Filled Double—Exchange Model at Finite Temperature

We extend a previous result of ours [G.S. Tian, Phys. Rev. B63 (2001) 224413] on the antiferromagnetic spin correlations in the half-filled Hubbard model at finite temperature to the double-exchange model. To overcome the mathematical difficulty caused by the localized spin freedom in this model, we apply both Zener's argument and the finite-temperature spin-reflection-positivity method to show rigorously that, at any temperature , the spin correlations in the half-filled double-exchange model are predominantly antiferromagnetic. This conclusion is completely consistent with the experimental observations and the previous theoretical results by approximate methods.

Variability and correlation analysis of physical and mechanical indexes of loess in western Liaoning

Based on the method of probability and statistics, the authors analyzed the physical and mechanical properties of loess in specified area, and discussed its main indexes, the coefficient of variation, and the corre- lation among the physical and mechanical indexes. Regression equations are built among those indexes, the re- suits show that the variability of mechanical indexes is higher than that of the physical indexes, and the physical indexes have better correlation than the relation between physical and mechanical indexes. The conclusions of this study would contribute to further research about loess in western Liaoning.

Modeling Evolution of Weighted Clique Networks

We propose a weighted clique network evolution model, which expands continuously by the addition of a new clique （maximal complete sub-graph） at. each time step. And the cliques in the network overlap with each other. The structural expansion of the weighted clique network is combined with the edges＇ weight and vertices＇ strengths dynamical evolution. The model is based on a weight-driven dynamics and a weights＇ enhancement mechanism combining with the network growth. We study the network properties, which include the distribution of vertices＇ strength and the distribution o~ edges＇ weight, and find that both the distributions follow the scale-free distribution. At the same time, we also find that the relationship between strength and degree of a vertex are linear correlation during the growth of the network. On the basis of mean-field theory, we study the weighted network model and prove that both vertices＇ strength and edges＇ weight of this model follow the scale-free distribution. And we exploit an algorithm to forecast the network dynamics, which can be used to reckon the distributions and the corresponding scaling exponents. Furthermore, we observe that mean-field based theoretic results are consistent with the statistical data of the model, which denotes the theoretical result in this paper is effective.

Research on the Correlation of the Fluctuating Density Gradient of the Compressible Flows

This work is to study a role of the fluctuating density gradient in the compressible flows tbr the computational fluid dynamics （CFD）. A new anisotropy tensor with the fluctuating density gradient is introduced, and is used for an invariant modeling technique to model the turbulent density gradient correlation equation derived from the continuity equation. The modeling equation is decomposed into three groups proportional to the mean velocity, proportional to the mean strain rate, and proportional to the mean density. The characteristics of the correlation in a wake are extracted from the results by the two dimensional direct simulation, and shows the strong correlation with the vortices in the wake near the body. Thus, it can be concluded that the correlation of the density gradient is a significant parameter to describe the quick generation of the turbulent property in the compressible flows.

Correlation of Two Coupled Particles in Viscoelastic Medium

Considering the viscoelastic memory effect, we study the correlated motion of two hydrodynamically coupled colloidal particles, each of which confined in a harmonic potential well, in a Kelvin-type and Maxwell-type viscoelastic medium. We find that viscoelastic relaxation plays a significant role in modifying the correlation, particularly the cross correlation. We also find that both the real and imaginary parts of the response function are significantly different from the viscous medium case. In particular there is a phase shift between the vanishing imaginary part and the maximal real part of the response function in a viscoelastic medium. In addition imaginary part of the cross correlation response function exhibits a net energy loss （gain） behavior when the elasticity parameter of the medium is larger （smaller） than the critical value for Kelvin （Maxwell） viscoelastic fluid. Some implication of our results and their connection with previous works are discussed.

On Improving Students＇ Listening Proficiency From Correlation Analysis Between English Listening and Other English Skills

Researches have proved that in human beings＇ actual languange communication, listening is the most important part. However, in English learning, listening seems always to be a weakness for many Chinese students. English learning is a systematic process, during which, English listening proficience is influeced by many factors. Therefore, from the systematicness and inner relations in English learning and based on qualitative analysis and quantitative analysis between English listening and other English skills in English listening, this paper tries to give the correlation analysis and accordingly give some suggestions to improve listening proficiency for ESL （English as a second language） learners

A Study of College Students＇ Autonomous English Listening Ability

Based on the data got from questionnaire in which 75 college students from Heze University participated, the present study aims to explore the current situation of college students＇ autonomous listening ability, its gender difference and the correlation between autonomous listening ability and CET-4 listening achievement. The results indicate that the autonomous listening ability for college students is at the medium level with a great individual difference and there＇s a vast space to be promoted. Moreover, there＇s no significant gender difference in autonomous listening ability for college students and there＇s significant positive correlation between autonomous listening ability and CET-4 Listening achievement, especially the dimension of Application of Strategies. Thus, a conclusion can be drawn that in English listening teaching, teachers should change their teaching model and strengthen the application of network teaching; in English listening learning, English learners should promote their ability of using strategies in English listening in order to improve their autonomous learning ability.

基于稳定性的第三代先进高强钢设计

第三代先进高强钢(TG-AHSS)是近年来材料科学与汽车工业领域的研究热点。本文针对TG-AHSS的成分设计、热处理工艺及强韧化机制,基于热力学稳定性阐明了第三代先进高强钢成分设计的宗旨,基于广义稳定性对几类代表性热处理工艺进行了诠释。在此基础上,从广义稳定性与热-动力学相关性形成的热-动力学贯通性入手,对第三代先进高强钢的强韧化机制进行了总结和归纳。从热-动力学角度,对第三代先进高强钢的设计策略进行了展望。

细胞外基质的硬度与细胞生物学功能的研究进展

细胞外基质是细胞赖以生存的环境,细胞外基质中物质和代谢的不平衡导致细胞外基质硬度的变化,从而能够影响细胞的一系列生物学功能。本文阐述了近期关于细胞外基质的改变与力学相关性的研究,以及其对细胞的迁移、细胞核形态的改变、细胞分化、基因转移、细胞的信号转导方面的影响。

ELF MOTIVATIONS AND AUTONOMY IN ENGLISH LEARNING:AN INVESTIGATION OF CHINESE NON-ENGLISH MAJOR UNDERGRADUATES

本文将英语学习动机作为影响自主性英语学习能力(AEL)的一个因素,采用定量与定性相结合的方法,通过对471名非英语专业二年级大学生进行"非英语专业大学生英语学习动机与自主性英语学习能力"的调查,发现不同类型动机与自主学习能力之间存在不同程度的相关。结合相关理论,作者对二者之间的相关性进行了分析,并提出了相关的建设性意见。

Relationship between triphasic mechanical properties of articular cartilage and osteoarthritic grade

The purpose of this study was to explore the triphasic mechanical properties of osteoarthritic cartilage with different pathological grades.First,samples of cartilage from rabbits with different stages of osteoarthritis (OA) were graded.Following this,the cartilage was strained by a swelling experiment,and changes were measured using a high-frequency ultrasound system.The result,together with fixed charge density and water volume fraction of cartilage samples,was used to estimate the uniaxial modulus of the cartilage tissue,based on a triphasic model.For the control cartilage samples,the uniaxial elastic modulus on the cartilage surface was lower than those in the middle and deep layers.With an increase in the OA grade,the uniaxial elastic modulus of the surface,middle and deep layers decreased.A significant difference was found in the surface elastic modulus of different OA grades (P<0.01),while no significant differences were identified for OA cartilages of Grades 1 and 2 in the middle and deep layers (P<0.01).Compared with Grades 1 and 2,there was a significant reduction in the elastic modulus in the middle and deep layers of Grade 3 OA cartilage (P<0.05).Overall,this study may provide a new quantitative method to evaluate the severity of OA using the mechanical properties of cartilage tissue.