γ-氨基丁酸晶体成核动力学、晶体生长及热力学性质研究

本文研究了γ-氨基丁酸的热力学及成核动力学性质.对γ-氨酪酸晶体的热力学性质进行研究,γ-氨基丁酸的差示扫描量热研究表明:γ-氨基丁酸的熔点为190.6 ℃,熔化焓为-343.4 J/g.测定了不同温度下γ-氨基丁酸在水中的溶解度及不同过饱和度下的诱导期.结果表明:γ-氨基丁酸的诱导期随着过饱和度的增加而降低.通过经典成核理论计算了固-液表面张力、成核自由能和临界成核半径.     

香草醛晶体光学非线性系数的有限场方法研究

采用有限场方法计算了有机非线性材料3-甲氧基-4-羟基-苯甲醛(分子式C~8H~8O~3,简称MHBA)的二阶非线性光学系数d~2~1,d~2~2,d~2~3,d~2~5。研究结果表明在MP2近似和6-31G+(p,d)基组水平上理论值能较好地与实验值符合,同时也表明拉电子基团HC＝O和推电子基团HO对MHBA分子的光学非线性性能的影响很大,而晶体中分子间的氢键作用对d值的贡献很小。     

GENERALIZATION OF ESHELBY'S METHOD TO THE ANISOTROPIC ELASTICITY THEORY OF DISLOCATIONS IN QUASICRYSTALS

The general expressions of the elastic fields induced by straight dislocations in quasicrystals have been given according to Eshelby's method which was used to treat the anisotropic elasticity of dislocations in crystals. As an example, the elastic displacement vector, the stress tensor and the elastic energy density of a screw dislocation line lying on the quasiperiodic plane of decagonal quasicrystals are calculated.     

Theoretical Studies on the Electronic Properties of R_2M_(14)B (R = Lanthanides from La to Lu;M = Mn,Fe, Co,and Ni)

To search for an alternative for Nd₂Fe₁₄B,we have studied the electronic structures of R₂M₁₄B compounds,where R stands for rare-earth element and M for Mn,Fe,Co and Ni.By density functional theory(DFT),we discuss the atomic coordination environment and partial density of states(PDOS)in detail,with the emphasis on the interaction between the six kinds of M sites and the R atoms.We systemically calculated the electronic structures of sixty R₂M₁₄B compounds to provide systematic and reliable results for explaining the origination of magnetism,which is important for further development of Nd₂Fe₁₄B based magnet materials.     

含Pt配合物电子结构和非线性光学性质的TDDFT研究

利用含时密度泛函理论(TDDFT)对trans-(PEt3)2Pt(X)(p-Ph-NO2)的有机金属配合物进行结构优化, 并计算了电子光谱和二阶非线性光学(NLO)性质, 结果表明在1064 nm光场下, 2个分子的共振效应很强, 在远离共振的1907nm的下, 分子的一阶超极化率是尿素的40倍左右。     

应用角度重叠模型推求任意对称场中的配体场势函数

配体场理论认为,在配合物中,中央体的能级分裂主要取决于配体在中央体处的配体场势。配体场势函数的形式取决于配合物中配体的个数和配体分布的对     

十次对称准晶中直位错的弹性位移场

根据作者提出的准晶中缺陷的弹性模型,导出了三维空间的十次准晶中的直位错引起的弹性位移场的表达式。     

图式流形

The discovery of manifold is a major advance in modern mathematics.In 1974,J.W.Morgan and D.P.Sullivan Surggest the concept of a Z/n manifold.We think that,it is more useful to suggest the concept of a graphlike manifold and research related topics.And these works will be done in this paper.     

MRCI及其近似方法下C2分子X1Σ+g, B1Δg和 B′1Σ+g态的势能曲线

运用MRCI及其近似方法计算得到C₂分子X¹Σ⁺_g, B¹Δ_g和B′¹Σ⁺_g 3个电子态的势能曲线, 并以FCI方法为基准, 考察比较各种方法的优缺点. MRCI计算与FCI计算几乎不存在差别, 在FCI计算不现实的情况下, MRCI计算足以作为基准考验其他计算方法. 多种近似方法均能达到化学精度, 并提出一个有效的选择参考组态的方法, 提高MRCI计算效率的同时, 保证计算的精确性.     

β—羧基—α—（取代苯基）乙基锗的倍半氧化物的合成

β-羧基乙基锗的倍半氧化物是日本学者七十年代初首次合成的,具有广谱生物活性和药理活性。大量的研究证明:它有明显的抗癌活性、干扰素的诱发作用、治疗高血压、放射增敏作用、促进毛发生长、植物生长调节作用等,并且几乎无毒,但其脂溶性很差,在体