Unique conformation and packing structure of p-sulfonatocalix[5]arene induced by 1,2-bis(pyridinium)ethane compounds

In the presence of 1,2-bis(4,4'-dipyridinium)ethane, p-sulfonatocalix[5]arene (C5AS) adopts an unseen partial-cone conformation to form back-to-back dimers, whereas C5AS crystallizes in face-to-face dimers to form a wavy layer, rather than the expected bilayer, arrangement upon complexation with 1,2-bis(pyridinium)ethane.     

The influence of Cu(II), Mg(II) on the binding of adriamycin with DNA and the study on their interaction mechanism

Cu(II) and Mg(II) have different binding capacity with daunomycin, and have different combination mode with DNA. Selecting these two different metal ions, the influence of them on the binding constant of adriamycin with DNA and the related mechanism has been studied by using absorption and fluorescence spectroscopy. The result showed that Mg(II) has weaker binding capacity with the drug comparing Cu(II), but both Mg(II) and Cu(II) can obviously reduce the binding constant of DNA with the drug. Addition of Cu(II) to the drug-DNA binary system can cause the reduction of fluorescence in the system, but addition of Mg(II) to it can cause the enhancement of fluorescence in some conditions. This show that the influence of Cu(II) and Mg(II) on the binding of the drug with DNA may be by a different mechanism. According to the main function of Mg(II) to bind with the phosphate groups on DNA, it can be deduced that for the interaction of the aglycon portion of the drug into the base pairs of DNA, the electrostatic binding between amine group of the drug with the phosphate group on DNA is a prerequisite.     

Study of B c → D π in the perturbative QCD approach

We investigate the branching ratios and direct CP-asymmetries of the and decays in the PQCD approach. All the diagrams with emission topology or annihilation topology are calculated strictly. A branching ratio of 10^-6 and 10^-7 for and decay is predicted, respectively. Because of the different weak phase and strong phase from penguin operator and two kinds of tree operator contributions, we predict a possible large direct CP-violation: and when γ = 55°, which can be tested in the coming LHC. PACS: 13.25.Hw, 12.38.Bx     

A theoretical and experimental study on all-normal-dispersion Yb-doped mode-locked fiber lasers

We report on a theoretical and experimental study of an all-normal-dispersion (ANDi) Yb-doped mode-locked fiber laser, in which nonlinear polarization rotation (NPR) is used to realize mode-locking without any dispersion compensation. Based on the coupled nonlinear Schrdinger (CNLS) equation, a model simulating the mode-locked process of an allnormal-dispersion ring fiber laser is developed, which shows that the achievement of stable mode-locking depends on the alignment of the polarization controller (PC) along the fast-polarization axis of the fiber, the birefringence intensity, and the net cavity dispersion. According to the theoretical analysis, stable mode-locked pulses with pulse duration 300 ps and average output power 33.9mW at repetition rate 36MHz are obtained.     

Temperature Influence on Divergence Angles of Quartz Crystal Wollaston Prism

We propose a structural angle and main refractive indices as two key factors to understand the temperature influence on the divergence angles of the Wollaston prism. The temperature influence on the divergence angles of quartz crystal Wollaston prism is studied theoretically. The results show that divergence angles decrease with increasing temperature, while the divergence angle of e-light decrease more quickly than that of o-light. The testing system is established to verify the above results, and the experimental results are in agreement well with the theoretical analysis.     

Novel identification approach for nonlinear systems with hysteresis

Nonlinear Dynamics - A new identification approach for a nonlinear system with hysteresis, namely a cascading Bouc–Wen hysteresis model with linear dynamics, is proposed in this study. The...     

Synthesis,Crystal Structure,and Properties of a 2D Cu(I) Coordination Polymer Based on Cu<Subscript>3</Subscript>I<Subscript>3</Subscript> Chains Linked by 1,3-Di-(1,2,4-Triazole-4-yl)Benzene

A new copper(I) iodide coordination polymer, [(CuI)₃(dtb)] _n (1) (dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene) has been synthesized solvothermally and structurally characterized by single crystal and powder X-ray diffractions, elemental analysis, IR, and thermogravimetric analysis. Overall, 1 exhibits a 2D hybrid structure containing dtb as structure-directing agents (SDAs) and 1D Cu₃I₃ chain as inorganic moiety. The copper-iodide chain can be regarded as two Cu₂I₂ rhomboids are connected by CuI fragments via Cu–I bonds. Dtb act as bridging ligands regularly link the Cu₃I₃ chains along both sides through Cu–N bonds to give the final 2D network. Moreover, solid state luminescent property of 1 has been investigated at room temperature.     

Structure elucidation and antitumour activity of a new macrolactam produced by marine-derived actinomycete Micromonospora sp. FIM05328

Chemical investigation of a marine-derived actinomycete strain Micromonospora sp. FIM05328 isolated from a soil sample collected from the East China Sea, resulted in the discovery of a new 26-membered polyene macrolactam metabolite FW05328-1 (1), together with a known polyene with pyridone ring compound aurodox (2). The structures of compounds 1 and 2 were determined by the detailed analysis of 1D, 2D NMR and HR-TOF-MS data, along with literature data analysis. 1 and 2 exhibited excellent antiproliferative activities against KYSE30, KYSE180 and EC109 human tumour cell lines, but displayed no antibacterial activities against bacteria or fungi were tested.     

新型N,N'-二(邻氧乙酸)苄叉丙二胺合铜(II)和镍(Ⅱ)及N-(邻氧乙酸)苄叉丙二胺合铜(Ⅱ)的合成、晶体结构及抑菌活性

在乙醇和水的混合溶液中, 将N,N'-二(邻氧乙酸)苄叉丙二胺(1)与氯化铜反应, 获得配合物Cu(Ⅱ)L1·H2O·0.25CH3CH2OH(2)[L1=N,N'-二(邻氧乙酸)苄叉丙二胺]; 当将反应混合溶液的pH值调至8~9, 获得Cu(Ⅱ)ClL2·3H2O(3)[L2=N-(邻氧乙酸)苄叉丙二胺]; 将N,N'-二(邻氧乙酸)苄叉丙二胺(1)与氯化镍反应, 获得配合物Ni(Ⅱ)L1·2.75H2O(4). 用元素分析、1H NMR和IR谱等方法对所合成的化合物1和配合物2~4进行了表征, 并测定了配合物2~4的晶体结构. 在配合物2中, 铜原子为六配位[CuN2O4], 在配合物3中, 铜原子为六配位[CuN2O3Cl], 在配合物4中, 镍原子为六配位[NiN2O4], 三个配合物均为畸变八面体结构. 抑菌活性大小的顺序: 配合物3>配合物2>化合物1.     

Synthesis,Crystal Structure,and Photoluminescent and Semiconductive Properties of [La(C_6NO_2H_5)_3-(H_2O)_2]_(2n)·(nH_5O_2)(nHgCl_5)(2nHgCl_4)·(2nH_2O)

A new heterometallic 4f-5d inorganic-organic metal-isonicotinic acid complex [La(C6NO2H5)3(H2O)2]2n·(nH5O2)(nHgCl5)(2nHgCl4)·(2nH2O) 1 has been synthesized via hydro-thermal reaction and structurally characterized. Complex 1 crystallizes in the space group C2/c of monoclinic system with four formula units in a cell:a =24.140(7),b=20.884(7),c=15.462(2),β=127.46(1)°,V=6187(3)3,C36H47Cl13Hg3La2N6O20,Mr=2224.24,Dc=2.388 g/cm3,Z=4,T=293(2) K,μ(MoKα)=9.401 mm-1,F(000)=4160 and R/wR=0.0376/0.0636 for 4130 observed reflections (I > 2σ(I)) and 5617 unique reflections. Complex 1 is characteristic of a one-dimensional polycationic chain-like structure. Photoluminescent investigation reveals that the title complex displays interesting emissions in violet and orange regions. The luminescence spectra show stronger orange emission than violet emission. Optical absorption spectra of 1 reveal the presence of a wide optical bandgap of 3.41 eV.