With the development of reform and open policy, foreign languages become more and moreuseful. And how to teach a foreign language is an important matter. A lot of methods of teaching foreign languages have been develo...With the development of reform and open policy, foreign languages become more and moreuseful. And how to teach a foreign language is an important matter. A lot of methods of teaching foreign languages have been developed. There’re grammar-trans-lation method, direct method, audio-lingual method, communicative method, etc. In this paper I in-展开更多
This paper reviews the investigation status of the techniques for preparation of metal matrix composites and the research outcomes achieved recently. The mechanisms, characteristics, application ranges and levels of d...This paper reviews the investigation status of the techniques for preparation of metal matrix composites and the research outcomes achieved recently. The mechanisms, characteristics, application ranges and levels of development of these preparation techniques are analyzed. The advantages and the disadvantages of each technique are synthetically evaluated. Lastly, the future directions of research and the prospects for the preparation techniques of metal matrix composites are forecasted.展开更多
Advantages and disadvantages of four transfection methods of DNA vaccines into the body were introduced in this study, including direct transfection, transfection of bacterial vectors, cationic lipofection and cationi...Advantages and disadvantages of four transfection methods of DNA vaccines into the body were introduced in this study, including direct transfection, transfection of bacterial vectors, cationic lipofection and cationic polymer transfection. Cationic polymer had the characteristics of high transfection efficiency, simple operation, wide application, good repeatability and low cell virulence, which could be expected as a new kind of effi- cient transfection reagents. In practical application, various transfection methods have their own advantages and disadvantages, so the best choice should be made in the design process of vaccines based on targets, test cost, using objects and its convenience.展开更多
English has become the medium for communication in so many areas, and children are the hope of the future and shoulder the duties to structure the future. Children＇s English becomes more important and spreads all ove...English has become the medium for communication in so many areas, and children are the hope of the future and shoulder the duties to structure the future. Children＇s English becomes more important and spreads all over the world, especially in recent years. Children＇s English is not perfect and there exist its own disadvantages. This paper gives four optimizations and suggestions in teaching children＇s English in order to solve the problem. Then it lists several relations to the children＇s English study, and these four relations are very important because they are the keys to lead the children＇s English to a healthy and developing road. And in the next chapter, it talks about the trends of the children＇s English in the future and lists the reasons why these kinds of trends appear. At last, the author overlooks the whole paper and gives a conclusion, which shows that children＇s English has a great potentiality in the future in China.展开更多
文摘With the development of reform and open policy, foreign languages become more and moreuseful. And how to teach a foreign language is an important matter. A lot of methods of teaching foreign languages have been developed. There’re grammar-trans-lation method, direct method, audio-lingual method, communicative method, etc. In this paper I in-
文摘This paper reviews the investigation status of the techniques for preparation of metal matrix composites and the research outcomes achieved recently. The mechanisms, characteristics, application ranges and levels of development of these preparation techniques are analyzed. The advantages and the disadvantages of each technique are synthetically evaluated. Lastly, the future directions of research and the prospects for the preparation techniques of metal matrix composites are forecasted.
基金supported by Project of Zhejiang Province(2006C12086)
文摘Advantages and disadvantages of four transfection methods of DNA vaccines into the body were introduced in this study, including direct transfection, transfection of bacterial vectors, cationic lipofection and cationic polymer transfection. Cationic polymer had the characteristics of high transfection efficiency, simple operation, wide application, good repeatability and low cell virulence, which could be expected as a new kind of effi- cient transfection reagents. In practical application, various transfection methods have their own advantages and disadvantages, so the best choice should be made in the design process of vaccines based on targets, test cost, using objects and its convenience.
文摘English has become the medium for communication in so many areas, and children are the hope of the future and shoulder the duties to structure the future. Children＇s English becomes more important and spreads all over the world, especially in recent years. Children＇s English is not perfect and there exist its own disadvantages. This paper gives four optimizations and suggestions in teaching children＇s English in order to solve the problem. Then it lists several relations to the children＇s English study, and these four relations are very important because they are the keys to lead the children＇s English to a healthy and developing road. And in the next chapter, it talks about the trends of the children＇s English in the future and lists the reasons why these kinds of trends appear. At last, the author overlooks the whole paper and gives a conclusion, which shows that children＇s English has a great potentiality in the future in China.
