The function of Gastrointestinal tract including intestine is to a large degree mechanical.The mechanical properties of the intestinal wall,and the tonic (sustained) and/or phasic(short-
99Tc is a fission product, and it has high fission yield (6%) and very long half-life (2.1×105 a). With the movement of nucleus, the concentration of 99Tc is increasing in the circumstance. So it's important ...99Tc is a fission product, and it has high fission yield (6%) and very long half-life (2.1×105 a). With the movement of nucleus, the concentration of 99Tc is increasing in the circumstance. So it's important to measure the concentration of 99Tc in the circumstance, and accelerator mass spectrometry (AMS) might be the best method for 99Tc measurement. The 93Nb is used for AMS instrument normalization, sample matrix. And we used the difference of energy loss and deducting the isotope to measure the 99Tc in a series of standard samples. And the results show that the AMS is the feasible measurement method.展开更多
A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is ...A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is constructured.Any world to be modelled can be logically specified in this Language. The integrity constraints on the database and the deducing rules within the Database world are derived from the proper axioms of the world being modelled.展开更多
With respect to the mathematical structure supposed by theEntity-Roles Model. a first order (three--valued) logic language is constructured. A world to be modelled can be logically specified in this language. The inte...With respect to the mathematical structure supposed by theEntity-Roles Model. a first order (three--valued) logic language is constructured. A world to be modelled can be logically specified in this language. The integrity constraints on the database and展开更多
Qualitative and quantitative researches are two major approaches in the study of second language learning and teaching, each representing a special research method in the anthropological studies. Qualitative approach ...Qualitative and quantitative researches are two major approaches in the study of second language learning and teaching, each representing a special research method in the anthropological studies. Qualitative approach moves from data to a hypothesis while the quantitative approach begins with a postulate and ends in the testing of the postulate with data, as a result, it is reasonable to take the qualitative approach as an inductive method and the quantitative approach as a deductive method. These two approaches both have their advantages and disadvantages. While doing qualitative research the researcher should bear in mind the different background of the students tested. On the other hand, the researcher using the quantitative method often suffers the limitation imposed upon him or her by the predefined requirement of the experiment. Only an apt and suitable coordination of the two approaches can make the study of second language teaching and learning successful and fruitful.\;展开更多
文摘The function of Gastrointestinal tract including intestine is to a large degree mechanical.The mechanical properties of the intestinal wall,and the tonic (sustained) and/or phasic(short-
文摘99Tc is a fission product, and it has high fission yield (6%) and very long half-life (2.1×105 a). With the movement of nucleus, the concentration of 99Tc is increasing in the circumstance. So it's important to measure the concentration of 99Tc in the circumstance, and accelerator mass spectrometry (AMS) might be the best method for 99Tc measurement. The 93Nb is used for AMS instrument normalization, sample matrix. And we used the difference of energy loss and deducting the isotope to measure the 99Tc in a series of standard samples. And the results show that the AMS is the feasible measurement method.
文摘A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is constructured.Any world to be modelled can be logically specified in this Language. The integrity constraints on the database and the deducing rules within the Database world are derived from the proper axioms of the world being modelled.
文摘With respect to the mathematical structure supposed by theEntity-Roles Model. a first order (three--valued) logic language is constructured. A world to be modelled can be logically specified in this language. The integrity constraints on the database and
文摘Qualitative and quantitative researches are two major approaches in the study of second language learning and teaching, each representing a special research method in the anthropological studies. Qualitative approach moves from data to a hypothesis while the quantitative approach begins with a postulate and ends in the testing of the postulate with data, as a result, it is reasonable to take the qualitative approach as an inductive method and the quantitative approach as a deductive method. These two approaches both have their advantages and disadvantages. While doing qualitative research the researcher should bear in mind the different background of the students tested. On the other hand, the researcher using the quantitative method often suffers the limitation imposed upon him or her by the predefined requirement of the experiment. Only an apt and suitable coordination of the two approaches can make the study of second language teaching and learning successful and fruitful.\;