希夫碱配合物RE_3L_6(NO_3)_6(H_2O)_2的合成与光谱性质

以4-氨基-1,2,4-三氮唑与对羟基苯甲醛为原料,在冰醋酸催化下合成了配体4-氨基-1,2,4-三氮唑缩对羟基苯甲醛(L)。然后利用4-氨基-1,2,4-三氮唑缩对羟基苯甲醛(L)与过渡金属硝酸盐[RE(NO_3)_2·xH_2O(RE=Cu,Co,Zn,Cd;x=3～6)]在无水乙醇中反应,制得固态配合物RE_3L_6(NO_3)6(H_2O)_2。通过元素分析、红外光谱、紫外光谱、荧光光谱等手段对合成的配体及配合物进行了表征。结果表明,RE_3L_6(NO_3)_6(H_2O)_2与RE(Ⅱ)发生配位作用的基团是配体中三氮唑环上的氮原子。     

A simple one step method for the synthesis of hexagonal Cd1 − xZnxS (x = 0-0.75)

Attempt has been made to synthesize hexagonal Cd_1 − xZn_xS (x = 0-0.75) by a simple solution phase method. The samples were characterized by XRD, SEM and UV-Vis spectroscopy. The XRD studies confirmed the formation of hexagonal modification of the above mentioned ternary system. SEM revealed formation of an agglomerated product with grain sizes of ∼ 100 nm. The mode of growth was confirmed as Ostwald ripening from UV-Vis studies. Shift in the exciton peak on increasing the Zn²⁺ was explained on the basis of formation of the solid solution. Photoluminescence studies reveal a shift in the luminescence band with Zn signifying the formation of solid solution. Also the band arises from the surface states demonstrating high concentration of surface defect states.     

双氮-苯硫脲C_(14)H_(14)N_4S_2的合成及晶体结构、光学和电化学性质

合成了标题化合物双氮-苯硫脲(BPTU,C14H14N4S2),并通过X射线衍射对其单晶结构进行了测定。该化合物属于单斜晶系,C2/c空间群,晶胞参数为a=2.692 4(7)nm,b=0.632 8(13)nm,c=0.944 5(19)nm,β=105.91(3)°,z=4。标题化合物具有缩氨基硫脲的顺式结构并且其分子结构略微歪斜,由于N H…S等分子间氢键作用,使得分子结构更趋稳定。通过红外光谱(IR)、紫外-可见光谱(UV-Vis)及循环伏安法(CV)等方法对化合物的光学性质和电化学性质进行了表征。     

Infrared and ultraviolet-visible spectroscopic studies of plasma polymerized 1, 1, 3, 3 - tetramethoxypropane thin films

Plasma polymerized 1, 1, 3, 3-tetramethoxy-propane (PPTMP) thin films of different thicknesses were prepared through glow discharge of 1, 1, 3, 3-tetramethoxypropane using a capacitively coupled reactor. The scanning electron micrographs show that as-deposited PPTMP thin films are smooth, uniform and pinhole free. Infrared spectroscopic investigation indicates the formation of conjugation along with C = O bonds in as deposited PPTMP thin films. Apart from aliphatic conjugation of C = C and C = O bonds there is formation of C-O-C bond owing to rearrangement of oxygen due to heat treatment of PPTMP thin films. A red shift in the maximum absorption wavelength of the ultra violet-visible spectra for all the PPTMP thin films is observed compared to the monomer maximum absorption wavelength. The absorption coefficient, allowed direct transition, E_qd, allowed indirect transition and E_qi, energy gaps were determined. The E_qd and E_qi are found to be about 2.92 to 3.16 eV and 0.80 to 1.53 eV respectively, for as deposited PPTMP samples of different thicknesses. The E_qi of two samples of different thicknesses heat treated at 673 K for 1 hour is 0.55 and 0.65 eV .     

亚麻籽油中木脂素（SDG）含量测定方法研究

采用紫外可见分光光度法测定亚麻籽油中木脂素类物质开环异落叶松树脂酚二葡萄糖苷(SDG)的含量。根据SDG在200~400 nm紫外区有特征吸收,由光谱扫描曲线可知最大吸收波长为280 nm,通过绘制标准曲线,得到SDG的浓度与吸光度之间的显著的线性关系。根据相似相溶原理,用甲醇振荡提取亚麻籽油中的SDG,且排除此波长处可能的干扰物质,测定吸光度,由回归方程计算SDG的含量。结果表明:此法简便、快速、稳定性好,平均加样回收率99.7%,RSD为1.9%。     

磁性负载钌催化剂的制备及其在吗啉存在下的稳定性研究

通过碱性条件下二氯化铁和三氯化铁的共沉淀法制备Fe3O4,表面SiO2包覆后得到磁性纳米粒子Fe3O4-SiO2,经过硅烷偶联剂上的Si-OMe与磁性载体上的Si-OH的异相缩合,将不同结构的硅烷偶联剂接到载体上,实现了磁性载体的表面功能化.利用载体上的官能团与钌的络合,成功地制备出磁性负载钌催化剂.应用UV-Vis分...     

紫外可见分光光度法研究金属卟啉与Lewis碱性溶剂的轴向配位作用

应用紫外可见分光光度法研究了氧钒－对四苯基卟啉（VOTPP）和镍－对四苯基卟啉（NiTPP）与Lewis碱性溶剂的轴向配位作用。结果表明，金属卟啉可以和一些Lweis碱性溶剂发生轴向配位作用。其特征紫外可见吸收峰发生红移；轴向配位作用与卟啉中心金属离子的外层d轨道电子数、碱性溶剂的供电能力及其空间构造有关，VOTPP比NiTPP更容易和Lewis碱性溶剂发生轴向配位作用；碱性强、空间阻碍小的Lewis碱性溶剂（如正丁胺）易于与金属卟啉发生轴向配位作用。     

Voltammetric and spectroelectrochemical studies on 4-aminophenol at gold electrodes in aqueous and organic media

Voltammetric and UV-Vis spectroelectrochemical studies on 4-aminophenol (4-AP) at gold electrodes have been carried out in conventional electrochemical and in novel spectroelectrochemical cells. As base electrolytes acetonitrile with 10⁻² M tetrabutylammonium hexafluorophosphate as supporting electrolyte and acetate buffer (pH 4.6) solutions have been used. 4-AP was electrochemically oxidized at gold electrodes at potentials >+0.1 V in aqueous solutions and at potentials >+0.5 V in acetonitrile solutions. The formation of an oxidation product has been characterized in situ by UV-Vis spectroscopy in a novel optical thin-layer spectroelectrochemical cell.     

The interaction between Ag+ and bovine serum albumin: a spectroscopic investigation

By using spectroscopic methods, we probed the interaction of Ag⁺ with bovine serum albumin (BSA) in an aqueous environment. Fluorescence of BSA quenched by Ag⁺ is a dynamic quenching process. Two binding modes-a strong one at low concentration of Ag⁺ and a weak one at high concentration were found. The association constant (K_A) and the number of binding sites (n) were 4.88 × 10³ M^− 1 and 1.17 for strong binding, and 17.6 M^− 1 and 0.547 for weak binding at 293 K. The results of thermodynamic parameters ΔH^θ, ΔG^θ and ΔS^θ for instinct binding modes at different temperatures indicated that the hydrogen bonding and van der Waals interaction play a major role for low Ag⁺/BSA ratio while electrostatic association for high Ag⁺/BSA ratio. Data of UV-Vis and Circular dichroism (CD) suggested that with the increasing amount of Ag⁺, the secondary structure undergoes a decrease in α-helix and an increase in β content and the backbone of BSA experiences a micro-environmental alteration. Furthermore, the distance r between donor (Trp-212) and acceptor (Ag⁺) was evaluated to be 10 nm according to nonradiative energy transfer theory.     

粘质沙雷氏菌代谢产物灵菌红素的鉴定

从柠檬酸厂糖化车间酸性土壤中筛选得到一株产红色素的粘质沙雷氏菌（Serratia marcescens）ZSG,菌株发酵液经酸性甲醇萃取、浓缩、硅胶柱层析、薄层色谱和柱色谱等分离纯化后,得到灵菌红素纯品,并采用紫外可见吸收光谱、红外光谱、液质联用分析对其结构进行了表征。