More attentionwas paid to the liquid crystal study in the past 30 years. Theirproperties, synthesis and applications have been deeply investigated. Liquid crystal technology is playing an important role in modern science and technology fields. This paper discusses the properties and applications of liquid crystal.

Conception is one of the bases of development of organic synthetic chemistry. A new conception can exploit a new research field and develop new orientations formodern organic synthesis. This paper introduces some new conceptions in themodern organic synthesis, reveals new achievements and improvement in the conceptions by giving some instances of organic synthetic reaction, summarizes the development orientations and the research fieldswhich should focus on.

The principles and characteristics ofaqueous two-phase extractionwere inruduced, and its developments in life science and processes of separation of complicated Chinese traditionalmedicine and separation of antibioticswere given. Furthermore, the developing trend of aqueous two-phase extractionwas also discussed.

More andmore attention is paid to the theory of constructivism in education field. It inspires a lot of thoughtful ideas to a new round reform ofcourse in elementary education. Based on the theory ofconstructivism, this papermainly discusses the effect of structural theory of learning on the reform ofcourse in elementary education at presen,t and teachers' idea-changing in chemistry teaching according to structural theory of learning.