蝎型钒氧配合物的合成、结构及量子化学研究

设计合成了两种新型的以聚类吡唑硼酸盐为配体的钒氧配合物VO(acac)[HB(pz)3](1)和VO(acac)[HB(3,5-Me2pz)3]·CH3CN(2). 运用元素分析、 红外光谱和紫外光谱对所合成的配合物进行了表征, 并用X射线衍射测定了它们的晶体结构. 同时, 采用量子化学的Hartree Fock方法和自然轨道分析方法(NBO), 使用3-21G*(6d, 7f)基组计算得到了两个分子体系的分子轨道、原子电荷以及键级, 并对其结构进行了分析.     

太阳CO 4.6微米红外成像观测

太阳红外光谱中蕴含着丰富的物理信息,其中CO 4.6μm波段是具有代表性的分子谱带,其形成于温度极小区附近,对研究太阳物理具有极其重要的意义。为获得CO 4.6μm波段太阳单色像,本文建立了一套全反射太阳红外成像观测系统。该系统采用定天镜跟踪引光,通过成像反射镜将太阳成像于3~5μm波段红外相机的焦平面上,该相机采用的是国产HgCdTe焦平面阵列器件。同时,为提高信噪比,提出了一种有效计算平场提取观测目标的方法,并利用该方法获得了CO 4.6μm波段的太阳单色像。     

无机分子纳米材料的研究进展

无机分子纳米材料是至少在一个维度上为纳米尺寸的分子及以其为单元组成的材料。由于其特殊的结构和性质，这种材料可以作为未来纳米分子电子器件、小分子吸附及储存材料。本文将从合成、结构、性质、应用等方面, 结合最新进展对这一充满活力并有着应用前景的领域作一简要概述。     

Preparation and electrochemistry of azobenzene self-assembled monolayers on gold--long range tunneling and end-group hydrogen bonding effect

A series of thiol-functionalied azobenzene derivatives (RAzoCnSH: R=H for n=3-6, abbreviated as AzoCnSH; R=CH(3)CONH for n=4, abbreviated as aaAzoC4SH) on gold electrodes were prepared and their self-assembly and electrochemical properties were studied by cyclic voltammetry. They all formed uniform and reproducible self-assembled monolayers (SAMs) on gold and showed well-behaved voltammetric responses in aqueous solution. Both the length of the alkyl chain spacer and the H-bonding of the end acetamino group had effects on the stability and the electrochemical kinetics of the SAMs, and the effect of the H-bonding was dominant. The surface coverage of the SAMs (AzoCnSH) is gradually increased with an increase of the alkyl chain spacer length, whereas the presence of the terminal acetamino group leads to a greater increase of the surface coverage. At a low scan rate, voltammetric responses corresponding to an irreversible two-electron, two-proton reduction/oxidation of the trans-azobenzene redox center were obtained in the range of +300 mV and -800 mV, which exhibited very large peak-to-peak splitting. At a high scan rate of 500 mV/s, two steps of reversible one-electron, one-proton reduction/oxidation corresponding to the cis-isomer in azobenzene-thiol SAMs (n is odd) was clearly observed between +300 and -200 mV. The apparent electron-transfer rate is decreased with increasing distance between the azobenzene redox center and the gold electrode. The existence of the end acetamino group which restricted the conformational change during the redox process also led to a decrease of the standard rate constant, and this restriction effect is more predominant than the distance effect.     

Cecropin B抗菌肽接枝丝素蛋白膜的制备和表征

以体积分数为60%的乙醇处理制得不溶性再生丝素膜, 通过碳二亚胺法将Cecropin B抗菌肽共价接枝到丝素膜表面, 利用红外光谱、扫描电镜、X射线能谱和抗菌性测试等手段对制得的丝素膜结构和表面特性及其抗菌性能进行了测试分析. 结果表明, Cecropin B抗菌肽成功地接枝到了丝素膜的表面, 接枝后的丝素膜水溶性低, 并具有良好、 持久的抗菌能力.     

微波辅助合成发光可调ZnS∶Cu纳米晶

以巯基丙酸(MPA)为稳定剂, 利用微波辐射加热方法制备了水溶性的Cu掺杂的ZnS纳米晶. 通过改变微波条件, 可以在460～572 nm之间实现对ZnS∶Cu纳米晶发射峰位的连续调控. 通过XRD、 UV-Vis、荧光及荧光衰减对ZnS∶Cu纳米晶的结构和发光性质进行了详细探索, 并利用时间分辨荧光光谱对其发光机理进行了初步研究.     

ELECTROCHROMETIC STUDIES ON POLAR MULTILAYERS OF LIQUID CRYSTALLINE POLYMERS

Electrochrometic measurements were carried on the Z-type Langmuir-Blodgett films oftwo liquid crystalline polymers: mono-{6-[4-(phenylazo) naphthyloxy] hexyl} (1a) andmono-{6-[4-(anthraquinone-1-azo) naphthyloxy] hexyl} (2a) ester of polymaleic acid. Itwas found that for both polymers, poling fields parallel and antiparalle1 to dipole momentsof the polymer side chains induce red and blue shift in absorption bands, respectively. Forpolymer la blue shift is accompanied by absorbance increase, while red shift by absorbancedecrease;but for polymer 2a only decrease in absorbance is observed. A simple model wasproposed to analyze the results.     

Structural Determination of Bis-histidinopeptide Zinc Complexes by 15N NMR (HMBC) Spectra

Polynitrogen receptors such as bis-histidine peptides possess strong ability to bind metals, which play much important roles in medicinal, bioinorganic, bioorganic, biomimetic and supramolecular chemistry. In order to investigate the interaction of these hosts with a variety of neutral, cationic and anionic guests, several techniques, for example, NMR,potentiometric tirations and monocrystal X-ray diffraction have been employed. Among them NMR is a powerful technique for unraveling the structure of polynitrogen receptors as long as they are in solution where the rapid tumbling of molecules averages out the anisotropies such as chemical shift and dipole-dipole interactions. General 1H NMR approach has been widely used for the study of host-guest interaction, but it is difficult for the accurate measurement in complexes structures, particularly metal complexes structures in which how the polynitrogen receptors bind metal, and which nitrogen binds metal and so on.     

吡嗪衍生物在石墨表面上的自组装单层膜结构

利用扫描隧道显微镜研究了荧光液晶分子2, 5-二-[2-(3, 4-二-十二烷氧基-苯基)-乙烯基]-3, 6-二甲基吡嗪(BPDP12)在石墨表面上自组装单层膜的结构. 实验结果表明, 该化合物在石墨表面形成两种自组装结构：一种是稳定的, 分子的共轭中心相互平行, 烷基链相互交错的密排结构；另一种是不稳定的, 分子的共轭中心彼此为烷基链所分隔的非密排结构. 分子之间较强的π-π作用和分子烷基链之间的范德华作用力对分子组装的取向形成竞争, 是产生两种不同组装结构的根本原因.     

二甲胺修饰戊二醛交联壳聚糖树脂的制备及性能

研究了在均匀水相介质条件下，采用戊二醛稀溶液制备交联壳聚糖树脂的方法，并以三聚氯氰为活化剂，合成了二甲胺修饰戊二醛交联壳聚糖树脂．研究了该树脂的红外光谱及吸附性能．该树脂对铜(Ⅱ)和牛血清白蛋白(BSA)的吸附容量分别为42mg／g(干)和940mg／g(干)，其吸附行为均符合Freundlich等温吸附模型．该树脂制备工艺简单，机械强度较好，可作为金属离子或蛋白质分离纯化的吸附剂和色谱填料．