烷氧基三联吡啶钌配合物的合成、结构及其与DNA相互作用

制备了2种含长基链的烷氧基三联吡啶和2,2''-联吡啶配位的钌配合物（Ru-Cl、Ru-NCMe）,通过质谱、核磁和单晶X射线衍射分析等进行了表征。从它们的晶体结构可以发现Ru-Cl配合物中第6个配位点为Cl-离子,在Ru-NCMe配合物中的第6个配位点为乙腈分子中的N原子。通过紫外可见吸收光谱和荧光光谱研究了这2种配合物与多种氨基酸和DNA的作用,发现这种长烷基链和刚性配位平面的配合物与DNA具有明显的特异性识别效应,进一步研究发现它们与DNA以插入方式和静电作用结合,实验与理论模拟结果一致。     

Imaging a periodic moving/state-changed object with Hadamard-based computational ghost imaging

We propose a method for imaging a periodic moving/state-changed object based on computational ghost imaging with Hadamard speckle patterns and a slow bucket detector, named as PO-HCGI. In the scheme, speckle patterns are produced from a part of each row of a Hadamard matrix. Then, in each cycle, multiple speckle patterns are projected onto the periodic moving/state-changed object, and a bucket detector with a slow sampling rate records the total intensities reflected from the object as one measurement. With a series of measurements, the frames of the moving/state-changed object can be obtained directly by the second-order correlation function based on the Hadamard matrix and the corresponding bucket detector measurement results. The experimental and simulation results demonstrate the validity of the PO-HCGI. To the best of our knowledge, PO-HCGI is the first scheme that can image a fast periodic moving/state-changed object by computational ghost imaging with a slow bucket detector.     

Raman analysis of epitaxial graphene grown on 4Hben SiC (0001) substrate under low pressure condition

In this paper, we report a feasible route of growing epitaxial graphene on 4H-SiC (0001) substrate in a low pressure of 4 mbar (1 bar=10⁵ Pa) with an argon flux of 2 standard liters per minute at 1200, 1300, 1400, and 1500 ℃ in a commercial chemical vapour deposition SiC reactor. Using Raman spectroscopy and scanning electron microscopy, we confirm that epitaxial graphene evidently forms on SiC surface above 1300 ℃ with a size of several microns. By fitting the 2D band of Raman data with two-Lorentzian function, and comparing with the published reports, we conclude that epitaxial graphene grown at 1300 ℃ is four-layer graphene.     

Teichmǖller Mappings, Harmonic Maps and Holomorphic Quadratic Differentials

Let M be a smooth,compact(closed and without boundary)surface.Consider the metrics σ(z)|dz|2 and ρ(ω)|dω|2 on M,where z=x+iy and ω=u+iv are conformal coordinates on M.     

Teichmüller Spaces and Function Spaces

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矩阵的正交次对角化

引进矩阵的一种新的“对角化”——正交次对角化的概念 ,并找出了矩阵可以正交次对角化的充分条件 .     

Fixpoints of Iterates and Quasinormal Families

Let A, B be two sets and f:A→B a map. The iterates f~n: A_n→B,n=1,2,…aredefined inductively by A_1=A, f~1=f and A_1=f~(-1)(A_(n-1)∩B), f~n=f~(n-1)(f) for n≥2.Note that A_2=f~(-1)(A_1∩B)A=A_1 and thus A_n A_(n-1) A for n≥2. A point x∈A is called a periodic point of period n of f if x∈A_n and f~n(x)=x, butf_j(x)≠x for any j less than n. A periodic point of period 1 is called a fixpoint. Then a periodic     

Teichmuller Mappings, Harmonic Maps and Holomorphic Quadratic Differentials

Let M be a smooth, compact (closed and without boundary) surface. Consider the metricsσ(z)|dz|~2 and ρ(ω)|dω|~2 on M, where z=x+iy and ω=u+iv are conformal coordinates onM. For a Lipschitz map ω=ω(z): (M, σ|dz|~2)→(M, ρ|dw|~2), we define the energy density of     

EDTA冠醚衍生物——Ⅷ.两个长桥链双冠醚的合成

前文报道的由EDTA桥联的水溶性双冠醚,虽然对碱土金属离子的配位有其特点,但可能是由于桥键不够长和二个刚性苯环的存在,桥键上两个羧甲基不但不起配位协同作用,反而阻碍了两个冠醚环的靠近,从而未显示出预期的高络合特性。为此,我们按下式合成了两个更长桥键的双冠醚1和2:     

丙烯酸酯基桥联γ-取代的β-二酮吡唑及异嗯唑衍生物的合成与表征

采用丙烯酸酯基桥联γ-取代的β-二酮分别与水合肼和盐酸羟胺反应，合成并表征了含有长链和共轭结构的吡唑和异嗯唑类新化合物，研究了不同溶剂对反应的影响．实验结果表明，当用乙醇为反应溶剂时，γ-取代的β-二酮与盐酸羟胺反应得到异嗯唑化合物；与水合肼反应不能得到目标吡唑化合物，而得到α，β-不饱和双键被还原的酰肼化合物；当用乙酸作为反应溶剂时，γ-取代的卢一二酮与水合肼反应得到目标毗唑类化合物．进一步探讨了生成酰肼化合物的反应历程。