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研究了余代数上余倾斜余模的结构特征,证明了每个余倾斜余模都可以写成不可分解的两两非同构的余模的直和形式,每个余倾斜余模包含所有的内射不可分解模作为直和项.最后构造了余倾斜余模的两个例子. 相似文献
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The polycrystalline sample of layered compound FePS_3 has been investigated by using M?ssbauer spectroscopy (12K to 300K), magnetic susceptibility measurements, x-ray diffraction and FTIR spectroscopy. The antiferromagnetic order exists below T_N=120.5±1K. The M?ssbauer spectra below T_N indicate that the magnetization axis is perpendicular to the layer of FePS_3, and the divalent iron cations are in their high spin configurations. By fitting the hyperfine field parameters near the Néel temperature, we obtain information on the nature of magnetic interactions in the material. The results show that the magnetic coupling can be treated by the two-dimensional Ising model, and it can be interpreted on the basis of a crystal-field effect. 相似文献
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One of the Prussian blue analogs, molecular magnet Cu3^Ⅲ [Fe^Ⅲ (CN)6]2.11.6H2 O, was investigated by Moessbauer spectroscopy. It was found that transition temperature was around Tc = 18.5 K from paramagnetic phase to ferromagnetic phase. The β value of the critical exponent is around 0.338 at magnetic ordering temperature.Therefore, the ferromagnetic coupling interaction of Cu-Fe cyanide could be clearly explained by spin wave theory. 相似文献
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用九速正方格子模型给出了二维对流扩散方程的格子Boltzmann方法。由对流扩散方程的对流系数和扩散系数确定了局域平衡分布函数的系数。计算机模拟结果与理论结果吻合很好。 相似文献
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将D-(+)-樟脑用二氧化锡氧化制得樟脑醌,再与系列取代邻苯二胺化合物缩合,合成得到19个樟脑基喹喔啉类化合物(3a~3s),并用UV-Vis、 1H NMR、 13C NMR、 FT-IR和HR-MS(ESI)进行结构表征。初步的抑菌和除草活性测试表明:在用药量为50 μg·mL-1时,目标化合物对花生褐斑病菌、小麦赤霉病菌、黄瓜枯萎病菌、苹果轮纹病菌、番茄早疫病菌、玉米小斑病菌、西瓜炭疽病菌以及水稻纹枯病菌等8种植物病原菌具有一定的抑制活性,其中化合物樟脑基5,8-二溴喹喔啉3r(R1=R4=Br,R2=R3=H)对苹果轮纹病菌的抑制率达78.6%,优于阳性对照百菌清。在用药量为100 μg·mL-1时,化合物樟脑基6-氟喹喔啉3f(R3=F, R1=R2=R4=H)和樟脑基7-氟喹喔啉3g(R2=F, R1=R3=R4=H)对油菜胚根生长的抑制率分别为75.8%和68.5%,均优于阳性对照丙炔氟草胺。
相似文献
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The static and dynamic magnetic properties of a Prussian blue analogue, molecular magnet Cu^Ⅱ_{3}[Fe^Ⅲ(CN)_6]_2·3NH_3·6H_2O were investigated in detail. The H dependence of the linear AC susceptibility, the irreversibility in the field-cooled (FC)/zero-field-cooled (ZFC) magnetization (M_{FC}/M_{ZFC}) and the relaxation of M_{ZFC} suggest that the magnetic system can be visualized as containing a ferromagnetic cluster of spin below T_C, mixed with small spin-glass clusters formed below temperature T_g less than T_C. The observed magnetic properties are explained with a ferromagnetic-spin-glass phase model. The magnetic ordering of the sample occurs below 19.8K. 相似文献
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