The quantum phenomenological model has been proposed to investigate the magnetic property of nanometer magnetic granular film in an applied magnetic field.The magnetoresistance of the granular films with two distinct magnetic phases has been calculated by using Born approximation.The results show that the average scattering cross section of the magnetic cluster decreases with the increasing number n of the atom.The origin of the giant magnetoresistance comes from the spin dependent scattering between conduction electrons and magnetic granules and the field dependence of magnetoresistance and the quadratic relation of magnetoresistance on the rate of magnetic moment are in good agreement with the experiments reported.
A series of 2-phenyliminothiazolidines has been successfully synthesized; and 2-(2-methylphenyl)iminothiazolidine(Ⅰa) and 2-(4-methylphenyl) iminothiazolidine(Ⅰb) have been selected to determine their crystal structures by X-ray diffraction technique, from their molecular graph of it is shown that double bond at 2-carbon atom of the heterocycle is all extro-cyclic at the crystal state, and there are two main plaines in Ⅰa and Ⅰb . But in Ⅰa , the angle between the planes is 61.4° and in Ⅰb the angle is about 41.4°. And so there is a strong conjugative effect in Ⅰb than in Ⅰa. So it is thought that the difference in fungicidal activies between 2-substitutedphenyl compounds(Ⅰa) and 4-substitutedphenyl compounds(Ⅰb) is due to their space factors.
Ten thiazoline compounds were synthesized starting from tetrahydrothiazoles. Their fungicidal activities against Phoma asparagi, Gibberella zeae, Cercospora beticola and Alteraria solani were examined. Some of them gave considerable good results.