芴取代的有机膦化合物的合成及发光性能

合成了以芴为取代基，P原子为核的一类新型有机膦化合物．此类化合物的HOMO值在-5．35～-5．24eV之间．在二氯甲烷中的最大紫外吸收光谱峰值在313～351nm之间，荧光光谱峰值在334～397nm之间．利用此类小分子与纯聚芴进行掺杂，制作了有机电致发光器件．低HOMO值有机膦化合物的引入有效地降低了聚芴发光器件的开启电压，提高了器件的发光效率．     

Molecularly imprinted TiO2 thin film by liquid phase deposition for the determination of L-glutamic acid

For the first time, the feasibility of a molecularly imprinted liquid phase deposition (LPD) thin film has been demonstrated. Thin films of titanium oxide imprinted with L-glutamic acid were prepared by the LPD method on a gold-coated quartz crystal microbalance. The imprinted molecule could be removed upon treatment with immersion in deionized water. A sensor was developed on the basis of this method and showed good sensitivity, selectivity, and reproducibility to the template molecule. An equation was deduced to characterize the interaction between molecularly imprinted films and the template by virtue of Scatchard analysis. X-ray photoelectron spectroscopy was introduced to show the evidence for the molecular imprinting phenomenon. The linear relationship between the frequency shifts and the concentration of analyte in the range of 10-200 microM was obtained. LPD proves to be a powerful method for imprinting titanium oxide thin films.     

源内裂解液相色谱-质谱鉴别人参皂甙砒和拟人参皂甙F11

研究了利用源内碰撞诱导解离（in-source collision—induced dissociation）的高效液相色谱-大气压化学电离质谱（HPLC—APCI／MS）获取人参和西洋参的化学标志物——人参皂甙Rf和拟人参皂甙F11的特征结构信息及鉴别人参和西洋参的方法。在乙腈-水梯度洗脱反相液相色谱及源内碰撞诱导解离条件下，能获得人参皂甙Rf和拟人参皂甙F11的母核离子及去糖基离子的源内碰撞诱导解离谱，从其差别能清楚区分这对同分异构体。本方法对人参皂甙Rf和拟人参皂甙F11的检出限能达到10^-7g柱上样量，简单、快速，单次质谱实验就能鉴别人参和西洋参。     

含芳硫基的新三唑类化合物的合成及生物活性研究

许多三唑类化合物具有优良的杀菌和植物生长调节活性 ,如三唑酮、三唑醇、烯效唑、烯唑醇等 ,对常见真菌病害具有很好的防治效果 ,并具有增产、抗倒和生长调节作用 ,已成为重要的杀菌剂类型 [1] .为筛选新型高活性三唑类杀菌剂和探讨其活性与结构间的关系 ,我们利用生物等排体理论以常规三唑类杀菌剂三唑酮为先导物设计合成了 1 6个含芳硫基的新三唑类化合物 ,其合成路线如下 :RCCH2 BrO+HNNNB NRCCH2O NNHAC-Na ACBr2NRCCHOBrNN(1 ) (2 ) (3 )3 +SH 　R′B NRCCHOS　R′NN　 (4 )RCCH2 CH2 NMe2 .HClO+HNNNH2 O…     

交联聚异丁烯酸甲酯型负载树脂的孔结构与分离稀土性能的关系

本文报导异丁烯酸甲酯型负载树脂的交联度、致孔剂组成和含量对负载树脂孔结构的影响.结果指出,良溶剂和劣溶剂按一定比例混合作为致孔剂,可制备不同孔结构的树脂.致孔剂量增加,树脂表观比重减小,而比表面积、孔体积与平均孔径均增加.交联度从10％增加到35%,表观比重和比表面积增加,而孔体积与平均孔径减小.增加致孔剂所含良溶剂的比例,树脂的表观比重、比表面积增加,而孔体积与平均孔径减小.已制备一系列不同孔结构的2-乙己基膦酸单2-乙己基酯(P507)负载树脂,比较了它们分离La、Ce、Pr、Nd的性能.结果表明,适当孔结构的负载树脂用于萃取色层分离稀土元素具有优良的分离性能.     

Molecular mechanics (MM3) parameterization of hydroxylamine and methyl derivatives

Based on results of electron diffraction, gas phase infrared spectroscopy (IR), and MP2/6-31 + G* ab initio calculations, a set of molecular mechanics (MM3) parameters was developed for molecules containing the N(sp³)—O(sp³) moiety. Using this set of parameters, MM3 is able to reproduce structures (bond lengths and bond angles) and vibrational spectra satisfactorily. © 1994 by John Wiley & Sons, Inc.     

溴化稀土冠醚配合物LnBr3(18-C-6)·nH2O的振动光谱与结构

本文合成了溴化稀土冠醚配合物, 测定了3500—100 cm~(-1)的付里叶红外和激光喇曼光谱, 并由振动光谱推断LnBr_3(18-C-6)·nH_2O的可能分子结构。     

Adsorption of CF4 on the internal and external surfaces of opened single-walled carbon nanotubes: a vibrational spectroscopy study

Infrared spectroscopy has been used to make the first experimental discrimination between molecules bound by physisorption on the exterior surface of carbon single-walled nanotubes (SWNTs) and molecules bound in the interior. In addition, the selective displacement of the internally bound molecules has been observed as a second adsorbate is added. SWNTs were opened by oxidative treatment with O(3) at room temperature, followed by heating in a vacuum to 873 K. It was found that, at 133 K and 0.033 Torr, CF(4) adsorbs on closed SWNTs, exhibiting its nu(3) asymmetric stretching mode at 1267 cm(-1) (red shift relative to the gas phase, 15 cm(-1)). Adsorption on the nanotube exterior is accompanied by adsorption in the interior in the case of opened SWNTs. Internally bound CF(4) exhibits its nu(3) mode at 1247 cm(-1) (red shift relative to the gas phase, 35 cm(-1)). It was shown that, at 133 K, Xe preferentially displaces internally bound CF(4) species, and this counterintuitive observation was confirmed by molecular simulations. The confinement of CF(4) inside (10,10) single-walled carbon nanotubes does not result in the production of lattice modes that are observed in large 3D ensembles of CF(4).     

Cloud Point Extraction Preconcentration of Trace Cadmium as 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone Complex and Determination by Flame Atomic Absorption Spectrometry

A new method for the determination of trace cadmium in water samples by flame atomic absorption spectrometry (FAAS) after cloud point extraction (CPE) is proposed. The method is based on the complexation of Cd with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) in the presence of non-ionic micelles of Triton X-100. The effect of experimental conditions such as pH, concentration of chelating agent and surfactant, equilibration temperature and time on cloud point extraction was studied. Under the optimum conditions, the detection limits are 0.64 ng mL^±1 with relative standard deviations (RSDs) of 2.1% (n = 10). The proposed method was applied to the determination of trace cadmium in water samples with satisfactory results.     

A novel method for the synthesis of the PEG-crosslinked chitosan with a pH-independent swelling behavior

In this study, a simple method was developed to crosslink chitosan using poly(ethylene glycol) (PEG) with different molecular weights. Crosslinking of chitosan was confirmed by various spectral analyses. The differential scanning calorimetric (DSC) study indicated that the rigid crystalline structure of chitosan was decreased after crosslinking with PEG. The PEG-crosslinked chitosan (PEG-Ch) showed a pH-independent swelling behavior: swelled in both the simulated stomach (pH 1.1) and intestinal (pH 7.4) solutions. The swelling ratio of PEG-Ch increased significantly with a higher molecular weight of PEG used. In contrast, chitosan dissolved completely in a simulated stomach solution and showed a comparatively less swelling in a simulated intestinal solution. Thus, the prepared PEG-Ch could be a better biomaterial than chitosan in the development of orally sustained drug-delivery devices.