以乙二胺为手臂分子制备的DNA修饰电极及其伏安性能

Carboxyl was formed on the surface of glassy carbon electrode(GCE) by electrochemical oxidation. Ethylenediamine(En) was used as the arm molecule to link carboxyl with dsDNA using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) and N- hydroxysuccinimide (NHS) as the activators to prepare dsDNA modified electrode(dsDNA/En/GCE). It was shown that dsDNA couM be covalently immobilized on the surface of GCE. ssDNA modified electrode(ssDNA/En/GCE) was obtained via the thermal denaturation of dsDNA/En/GCE. The dsDNA/En/GCE and ssDNA/En/GCE were characterized by voltammetry with methylene blue(MB) as the indicator. The results indicated that the currents of the redox peaks of MB at ssDNA/En/GCE were larger than those at dsDNA/En/GCE, and the currents of the redox peaks at En/GCE were the smallest. The peak-currents of MB at the DNA modified electrode had good reproducibility after multi-denaturation and hybridization cycles.     

酸性介质中Mn(Ⅲ)/Mn(Ⅱ)在铂电极上的氧化还原特性

氧化还原液流电池;扩散系数;循环伏安法;电位阶跃法;酸性介质中Mn(Ⅲ)/Mn(Ⅱ)在铂电极上的氧化还原特性     

聚天门冬氨酸合成过程中的水解反应

L-天门冬氨酸;;聚天门冬氨酸钠盐;聚丁二酰亚胺;水处理;阻垢作用;聚天门冬氨酸合成过程中的水解反应     

Intraband Dynamics and Terahertz Emission in Biased GaAs/In0.53Ga0.47As Semiconductor Superlattices

Using an excitonic basis, we investigate the intraband polarization, opticalabsorption spectra, and terahertz emission of semiconductor superlattice withthe density matrix theory. The excitonic Bloch oscillation is driven by the dcand ac electric fields. The slow variation in the intraband polarizationdepends on the ac electric field frequency. The intraband polarizationincreases when the ac electric field frequency is below the Bloch frequency.When the ac electric field frequency is above the Bloch frequency, theintraband polarization downwards and its intensity decreases. The satellitestructures in the optical absorption spectra are presented. Due to excitonicdynamic localization, the emission lines of terahertz shift in different acelectric field and dc electric field.     

The First Gallium Borophosphate NaGa[BP2O7(OH)3]:Synthesis and Crystal Structure Characterization

Borophosphates, as potential microporous materials, have drawn much attention in recent years and show rich chemistry^[1-3]. Although many compounds with transition metals have been reported, compounds with the p-block main group elements participating in the framework are rare^[4] The title compound has been synthesized by mild hydrothermal methods and crystal structure characterized by X-ray single crystal methods. Crystallographic data:monoclinic,C2/c (No. 15), a=10.408(3), b=8.094(2),c=9.099(2) Å, β=116.64(2), Z=4, R=0.0246,Rw=0.0676. The crystal structure contains isolated anions[(OH)O₂P_1/2-O_1/2B(OH)₂O_1/2-O_1/2PO₃]^4-. Geometrically, four GaO₆ groups with four PO₄ groups form an eight-member ring by sharing comers resulting to a two dimensional layer in be plane. The layers are joined by BO₄ group through comer sharing with GaO₆ and PO₄ and result to a three dimensional network structure. A 350pm x 600pm open channel along c-axis can be seen (figure below) and occupied by Na cations.     

A Luminescent Zn(Ⅱ) Supramolecular Coordination Polymer Constructed from 3,4-Thiophenedicarboxylic Acid and Flexible Benzimidazole-based Connector

A new luminescent coordination polymer [Zn(tdc)(pbim)]n 1(tdc = 3,4-thiophenedicarboxylate, pbim = 1,3-bis(benzimidazol-1ˊ-yl)propane) has been synthesized under hydrothermal conditions. The compound crystallizes in monoclinic system, space group P21/c with a = 8.4840(9), b = 16.4913(17), c = 14.9234(16) A, β = 95.8870(10)°, V = 2077.0(4) A3, Z = 4, Mr = 511.84, Dc = 1.637 Mg/m3, μ = 1.324 mm-1, F(000) = 1048, the final R = 0.0361 and w R = 0.0824 for 3656 observed reflections with I 2(I). Structural analyses reveal that 1 exhibits a onedimensional(1D) double chain, which is further connected into a two-dimensional(2D) supramolecular architecture by π-π stacking interactions. The results indicate that H2 tdc and pbim ligand are effective building blocks in constructing polymers with diverse architecture. Solid state properties for 1, such as infrared spectroscopy, elemental analyses, thermal stability and luminescent property, have also been investigated.     

DFT Study on the Heterofullerene C48O12 with Rare Th Symmetry

The molecule with T_h symmetry is rare. A novel C60-like molecule C48O12 with rare Th symmetry has been studied at the B3LYP/6-31G(d) level of theory. Its structural, electronic, vibrational, NMR, and thermodynamic properties have been calculated at the B3LYP/6-31G(d) level of theory. Vibrational modes have been assigned according to their symmetry. There are 73 independent vibrational modes: 22 IR-active modes with T u symmetry and 37 Raman-active modes with Ag , Eg and Tg symmetry, respectively. The heat of formation has been calculated by using isodesmic reactions, 765.7 kJ mol-1 . According to the heat of formation and the HOMO-LUMO gap, C48O12 with rare Th symmetry is more stable than C60 .     

3,5-二硝基苯甲酸冰片酯的合成及结构表征

冰片在中药中被广泛应用。利用前药原理,对冰片母体进行修饰,以冰片和3,5-二硝基苯甲酸为原料,以对甲苯磺酸为催化剂,合成了3,5-二硝基苯甲酸冰片酯,目标化合物的结构经FT-IR、13C NMR、1H NMR和元素分析加以确证。该化合物具有一定的研究开发价值。     

THE MAXIMAL NUMBER OF I_π-CHARACTERS OVER NORMAL SUBGROUPS

Let G be a π-separable group for a set of primes, let N be a normal subgroup of G, and let θ be an Iπ-character(i.e., irreducible π-partial character) of N. We obtain a necessary and suffcient condition for the number of Iπ-characters of G over θ to take the possible maximum |G : N |π. Some applications are given.     

静电陀螺仪MUM全姿态读取的原理及其误差分析

研究了采用同步解调法实现静电陀螺仪质量不平衡调制(MUM)全姿态读取的原理,讨论了影响读取精度的因素,分析了各电极轴转子位移测量电路比例因子不一致和电极轴不正交造成的读取误差.研究表明,某轴测量通道1%的比例因子偏差将造成约17′的读取姿态误差,电极轴不正交造成的读取误差与不正交的程度约在同一数量级.应用中必须通过建立读取误差补偿模型,并进行实时补偿来提高MUM全姿态读取的精度.