话语标记语的人文关照性

话语标记语对人们的实际言语交际起着重要的引导和制约的作用。语言的弹性和多功能性,对人与人之间交往的对话属性的揭示,是后期维特根斯坦和巴赫金哲学思想关注的要点。话语标记语的使用揭示了人类语言使用中的人文关照性。     

Using a Computer Animation to Teach High School Molecular Biology

We present an active way to use a computer animation in secondary molecular genetics class. For this purpose we developed an activity booklet that helps students to work interactively with a computer animation which deals with abstract concepts and processes in molecular biology. The achievements of the experimental group were compared with those of a control group by means of a written questionnaire, which the students received right after the molecular genetics instruction. Analysis of the post-test showed that the mean score of the experimental group was significantly higher than the mean score of the control group. This positive trend was also reflected in personal interviews.     

运用话语标记语提高听力理解能力——基于英语专业八级考试小讲座题型的实证研究

话语标记语在语言交际中起着重要作用。在听力理解中,听者可以运用话语标记语来引导自己更好地理解所听内容,话语标记语在帮助理解英语专业八级考试听力部分的讲座题型中具有重要作用。实证研究结果表明：用去除了话语标记语的讲座作练习的实验组所能理解的内容明显少于用带话语标记语的讲座作练习的对照组。     

Si原子在Si(001)表面及其台阶附近扩散的分子动力学模拟

采用Stillinger-Weber势,利用分子动力学方法模拟了Si原子在Si(001)表面和该表面单层台阶附近扩散的动力学过程。(1)给出单个Si原子在Si(001)表面垂直于二聚体排方向扩散的扩散路径和扩散机制。Si原子在Si(001)表面垂直于二聚体排方向扩散能够减弱Si原子在Si(001)表面扩散的各向异性。(2)模拟不仅给出与以往文献中原子从SA台阶下台面扩散到上台面相同的扩散路径而且还给出原子从成键的SB台阶上台面扩散到下台面的一种新的扩散机制:增原子通过与表面原子之间的交换。从而解释实验上观察到的Si(001)表面双层原子台阶形成的机制。无论是单个Si原子在Si(001)表面垂直于二聚体排方向扩散还是在Si(001)表面的单层台阶附近扩散,增原子和表面原子之间的交换机制都起着重要的作用。     

分子生物学知识体系建设与创新型人才培养

分子生物学是从分子水平阐述生物的生命现象和规律的学科,是生命科学的前沿学科。分子生物学在生物工程专业本科生培养中占有重要地位,更是学习生命科学、现代生物技术以及工业、农业、医药卫生和环境科学等各个领域的基础课程。本文探讨了工科本科生分子生物学知识体系建设的内容,阐述了分子生物学课程建设与创新型人才培养的方法。     

Using three-dimensional models to teach molecular structures in high school chemistry

The purpose of this study was to compare the effects of using two- and three-dimensional model representations of molecular structures on student learning of organic chemical structures. Organic structures were taught to high school students using one of four methods of molecular representation: (1) two-dimensional textbook representations, (2) three-dimensional computer models, (3) three-dimensional ball and stick models, and (4) combination of the computer molecular models and the ball and stick models. The computer software used in this study wasMolecular Editor. Students in the combination group of using both computer and ball and stick models scored significantly higher on the retention test of isomeric identification compared to the other groups. Molecules were represented in this test in the same mode as the instructional representation. However, on a similar two-dimensional post-instructional test of isomeric identification, this group had a significantly lower mean than the other groups; the two-dimensional group had the highest mean. This difference was not observed with the two-dimensional retention test of isomeric identification. When given a two-dimensional test of isomeric construction, no significant difference was found among the group means with either the posttest or the retention test.     

Microcalorimetric study on host-guest complexation of naphtho-15-crown-5 with four ions of alkaline earth metal

Thermodynamic parameters of complexation of naphto-15-crown-5 with four alkaline earth ions in aqueous mediawas determined using titration microcalorimetry at 298.15 K.The stability of the complexes,thermal effect and entropy effect ofthe complexation is discussed on the basis of the guest ions structure and the solvent effect.The stability constants tendency to varywith ion radius was interpreted.Complex of naphtha-15-crown-5 with calcium ion is very stable due to the synergism of staticelectric interaction and size selectivity between the host and the guest.