Quantum Solitary Wave Solutions in a Ferromagnetic Chain with Nearest- and Next-Nearest-Neighbor Interaction

The quantum solitary wave solutions in a one-dimensional ferromagnetic chain is investigated by using the Hartree-Fock approach and the multiple-scale method. It is shown that quantum solitary wave solutions can exist in a ferromagnetic system with nearest- and next-nearest-neighbor exchange interaction, and at the certain value of the first Brillouin zone, the solitary wave solution of the Hartree wave function becomes the intrinsic localized mode.     

关于高等数学中极限思想的研究

本文针对在工科高等数学的教学中 ,学生对极限这一重要概念难以把握和理解的现象 ,提出了分三个层次并从哲学的角度来理解这一思想 ,为学生最终解决这一难点提供了一种有效的方法 .     

利用目标试验因子分析法确定化学反应的级数及速率常数

利用目标试验因子分析(TTFA)结合数值遗传算法(NGA).解析反应过程中在线测得的动力学谱-光谱数据矩阵,可在未知各组分纯光谱及动力学模型情况下同时求解出各组分的纯光谱、反应级数及速率常数。提出用近似计算法计算各组分的动力学谱,使该方法能适用于任意反应级数的体系。针对两步连续反应模型,对反应物、中间体和最终产物均有吸收及某一种组分没有吸收的体系的模拟实验数据矩阵进行了处理,表明该方法均能适用。利用该方法对邻苯二甲酸二甲酯在碱性介质中的水解反应及日落黄水溶液的电解降解反应过程中测得的数据矩阵进行解析,均获得了可靠结果。     

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 .