What elements should be included in the REE group? This is one of the basic problemsof REE geochemistry. There are different viewpoints about this problem at present. For ex-ample, (1) P. Henderson et al. (1984) consi...What elements should be included in the REE group? This is one of the basic problemsof REE geochemistry. There are different viewpoints about this problem at present. For ex-ample, (1) P. Henderson et al. (1984) consider that, the REE include only lanthanons (Ln),namely, from lanthanum (La) to lutetium (Lu), but sometimes they also admit that theyttrium (Y), showing a similar chemistry to that of the REE, belongs to lanthanons. (2)B. I. Kogon (1979) et al. think that, the REE include not only Ln but also Y and scandium(Sc). (3) The author of the present paper (1982) and E. I. Semenov (1963) et al. considerthat the REE shouled include Ln and Y, whereas the Sc should not be included.展开更多
Do you enjoy Christmas parties?I must admit that at the mo-ment,now that the curtain is rising on the festive season,I lookforward to every social gathering I have been invited to.But I also know that when Christmas i...Do you enjoy Christmas parties?I must admit that at the mo-ment,now that the curtain is rising on the festive season,I lookforward to every social gathering I have been invited to.But I also know that when Christmas is over I shall sink backin front of the‘box’,relieved that it is all over.The last embar-rassment caused by some agonising clanger will be safely tuckedaway in my memory,never to be repeated.展开更多
The 1-dimensional all-pass filter energy delay problem was studied by Robison. His method is based on the canonical factorization theorem. However, multidimensional analytic function is so complicated that it does not...The 1-dimensional all-pass filter energy delay problem was studied by Robison. His method is based on the canonical factorization theorem. However, multidimensional analytic function is so complicated that it does not admit any canonical factorization representation like 1-dimensional one. So the multidimensional energy展开更多
文摘What elements should be included in the REE group? This is one of the basic problemsof REE geochemistry. There are different viewpoints about this problem at present. For ex-ample, (1) P. Henderson et al. (1984) consider that, the REE include only lanthanons (Ln),namely, from lanthanum (La) to lutetium (Lu), but sometimes they also admit that theyttrium (Y), showing a similar chemistry to that of the REE, belongs to lanthanons. (2)B. I. Kogon (1979) et al. think that, the REE include not only Ln but also Y and scandium(Sc). (3) The author of the present paper (1982) and E. I. Semenov (1963) et al. considerthat the REE shouled include Ln and Y, whereas the Sc should not be included.
文摘Do you enjoy Christmas parties?I must admit that at the mo-ment,now that the curtain is rising on the festive season,I lookforward to every social gathering I have been invited to.But I also know that when Christmas is over I shall sink backin front of the‘box’,relieved that it is all over.The last embar-rassment caused by some agonising clanger will be safely tuckedaway in my memory,never to be repeated.
文摘The 1-dimensional all-pass filter energy delay problem was studied by Robison. His method is based on the canonical factorization theorem. However, multidimensional analytic function is so complicated that it does not admit any canonical factorization representation like 1-dimensional one. So the multidimensional energy
