或许这个过程应正确地称为氟化.Perhaps the process should rightly be called fluoridation.异氰酸酯可由含氯的环(或非环)状分子氟化而得.The isocyanates can be obtained by the fluorination of nitrogenous cylic or acyclic molecules.在氟化过程中需要用一架 大功率 的电磁搅拌器.A heavy...
Alexander Graham Bell always lived by the philosophy that when one door closes , another one opens.亚历山大?葛理翰?贝尔一生都将“天无绝人之路”的哲学奉为圭臬.Every night, they go through the same routine: he throws open the bedroom window, she clos...