Application of Communicative Principles in Classroom Teaching of Listening

In the listening teaching classes in colleges and universities, it is still a common phenomenon that the teaching is conducted in a fixed mode： explanation of new words, listening and doing exercises and then checking of answers. Interactive activities are scarcely held. This article focuses on the application of communicative principles in classroom teaching of listening. The theoretic support for this practice is provided and the conduct of the specific application of communicative principles during the pre-listening, while-listening and post-listening phases in classroom teaching of listening is discussed.

Theory of numerical modeling of constitutive relation for geotechnical materials

Under the direction of the principle of interaction between plastic volumetric and shear strains, the general expression of constitutive relation for geotechnical materials has been derived within the framework of irreversible thermo- dynamics. The constitutive modeling, in fact, is an inverse problem that belongs to the medium inverse problems of model identification, which is expressed as a reversion of coefficient of differential equation. Thus the constitutive modeling of geotechnical materials will become the reversion of coefficient functions of the general expression of constitutive relation, which is carried out in the stress field （p,q） by means Of numerical techniques, so that is called numerical modeling. Applying the numerical modeling, a number of plasticity-based models for clay and sand have been obtained, which are able to characterize the fundamental features of deformation for geotechnieal materials. In addition, the approach of numerical modeling also can be applied to the situation of unsaturated soils by means of the Bishop＇s effective stress formula and Khalili＇s expression of effective stress parameter.

Behaviour of Humans and Behaviour of Models in Dynamic Space

This paper addresses new trends in quantitative geography research. Modern social science research--including economic and social geography--has in the past decades shown an increasing interest in micro-oriented behaviour of actors. This is inter alia clearly reflected in SIMs （spatial interaction models）, where discrete choice approaches have assumed a powerful position. This paper aims to provide in particular a concise review of micro-based research, with the aim to review the potential--but also the caveats---of micro models to map out human behaviour. In particular, attention will be devoted to interactive learning principles that shape individual decisions. Lessons from cognitive sciences will be put forward and illustrated, amongst others on the basis of computational neural networks or spatial econometric approaches. Particular attention will be paid to non-linear dynamic spatial models, amongst others, in the context of chaos theory and complexity science. The methodology of deductive reasoning under conditions of large data bases in studying human mobility will be questioned as well. In this context more extensive attention is given to ceteris paribus conditions and evolutionary thinking. The relevance of the paper will be illustrated by referring to various spatial applications in different disciplines and different application areas, e.g. in geography, regional science or urban economics.

Selective adsorption of liquid long-chainα-olefin/paraffin on Mg-MOF-74:Adsorption behavior and interaction mechanism

The liquid products of Fischer–Tropsch synthesis with a high content of linearα-olefins can act as valuable raw materials for increasing high added-valueα-olefin production if the challenging separation of long-chainα-olefin/paraffin is achieved.Adsorption separation is an efficient alternative to energy-intensive distillation.Herein,the selective adsorption behavior and interaction mechanism of liquidα-olefin/paraffin on Mg metal–organic framework(MOF)-74 were investigated using a combination of batch adsorption experiments and molecular simulation techniques.Mg-MOF-74 exhibited 301 and 333 mg/g olefin adsorption capacities for C6 and C8 linearα-olefins in binary olefin/paraffin mixtures,respectively,and was still unsaturated at high olefin concentrations.The adsorption isotherms were analyzed and compared with the simulated results by configurational-bias grand canonical Monte Carlo(CB-GCMC)simulation.The visualized adsorption sites by CB-GCMC simulation indicated that all adsorbates were arranged in hexagonal shapes and preferentially adsorbed by the vertex of the hexagon,where the metal node magnesium is located.The adsorption energies were−1.456 and−0.378 eV for C8 linearα-olefin and paraffin,respectively,calculated by density functional theory simulation based on the visualized adsorption sites.The charge transfer was analyzed,and the contributions of different kinds of interactions to the overall adsorption energy were quantified by principle orbital interaction analysis to further reveal the difference in adsorption energy betweenα-olefin/paraffin and Mg-MOF-74.This work also provides a general means to investigate the liquid adsorption performance and host–guest interactions in the adsorption or catalytic processes of nanoporous materials.