十二烷基磺酸根插层水滑石负载纳米钯催化的 Suzuki 偶联反应

 首次制备了十二烷基硫酸根 (DS–) 插层水滑石负载的纳米钯无膦配体型的 Suzuki 偶联反应催化剂. DS–进入到水滑石层间, 使层间距从微孔增至 2.9 nm, 从而有利于中等尺度的有机分子在催化剂表面的扩散. 进一步以 PdCl42–交换该水滑石得到 DS–和 PdCl42– 双插层的水滑石. 还原后可得到层间插有金属钯纳米团簇的水滑石. 由于 DS–插层后在水滑石层板间形成的空间有限, 限制了 Pd0 团簇的进一步生长. 作为一种亲油性的非均相催化剂, 该类催化剂可有效促进卤代芳烃与苯硼酸的 Suzuki 偶联反应. 催化剂循环使用 5 次后活性基本得以保持.     

鱼腥草中钛含量分析方法研究

The research of the effects of surfactants on coloring reaction between titanium and phenyl fluorone was developed.A survey of coexisting elements in the houttuynia cordata thunb was carried out by X-ray fluorescence spectrometry,and a series of interference tests and analyses were performed.The interference can be eliminated by processing through high temperature cineration and adding ascorbic acid.A new method of determination of titanium in houttuynia cordata thunb was established by phenyl fluorone spectrophotometry in the presence of Emulsifier OP.The results showed that Beer's law is obeyed within the range of 0～0.32 μg·mL-1 for titanium.The relative standard deviation(RSD) was 1.9%～2.0%,and the recovery was 96.8%～100.6%.The method was applied for determination of titanium in houttuynia cordata thunb with satisfactory results.     

纳米SiO2与阳离子表面活性剂的相互作用及其诱导的正辛烷-水乳状液的双重相转变

研究了3种不同结构的水溶性阳离子表面活性剂对纳米二氧化硅颗粒的原位表面活性化作用, 它们分别是单头单尾的十六烷基三甲基溴化铵(CTAB)、单头双尾的双十二烷基二甲基溴化铵(di-C12DMAB)和双头双尾的Gemini型阳离子三亚甲基-二(十四酰氧乙基溴化铵)(II-14-3), 并通过测定Zeta电位、吸附等温线及接触角等参数对相关机理进行了阐述. 结果表明, 阳离子表面活性剂吸附到颗粒/水界面形成以疏水基朝向水的单分子层, 从而增强了颗粒表面的疏水性是原位表面活性化的基础. 通过吸附CTAB和II-14-3, 颗粒的疏水性适当增强, 能吸附到正辛烷/水界面稳定O/W(1)型乳状液; 而通过吸附di-C12DMAB所形成的单分子层更加致密, 颗粒的疏水性进一步增强, 进而使乳状液从O/W(1)型转变为W/O型; 当表面活性剂浓度较高时, 由于链-链相互作用, 表面活性剂分子将在颗粒/水界面形成双层吸附, 使颗粒表面变得亲水而失去活性, 但此时体系中游离表面活性剂的浓度已增加到足以单独稳定O/W(2)型乳状液的程度. 因此当采用纳米二氧化硅和di-C12DMAB的混合物作乳化剂时, 通过增加di-C12DMAB的浓度即可诱导乳状液发生O/W(1)→W/O→O/W(2)双重相转变.     

驱油体系化学剂间相互作用对界面吸附膜的影响

采用界面张力弛豫技术研究了不对称Gemini表面活性剂C12COONa-p-C9SO3Na、部分水解聚丙烯酰胺Mo-4000、疏水缔合水溶性聚丙烯酰胺(HMPAM)等驱油体系化学剂在癸烷/水界面上的扩张流变性质,考察了不同离子强度、不同类型电解质对体系界面流变性质的影响,计算得到界面扩张弹性模量和粘性模量的全频率谱,并通过归一化方法(cole-cole图)探讨了界面吸附膜的弛豫过程。研究发现,界面膜内分子重排和界面与体相间分子扩散交换是影响膜性质的主要弛豫过程。表面活性剂体相浓度增大有利于界面分子重排过程,而低频有利于扩散交换过程;不同结构聚合物以及不同离子强度、不同类型电解质对表面活性剂吸附膜有不同的影响。     

二茂铁表面活性剂的电化学行为

以循环伏安法为主要手段,研究了具有可逆特性的二茂铁表面活性剂(N,N-二甲基二茂铁甲基十四烷基溴化铵,Fc14)在0.1 mol/L Na2SO4溶液中形成胶束对电化学行为的影响,并讨论了pH、扫描速度及浓度对Fc14电化学行为的影响.结果表明,Fc14在pH=2左右具有良好的可逆变化特性,在氧化态(I2+)与还原态(I+)之间可实现自由转换;Fc14在玻碳电极上的logIpc~logv呈现良好的线性关系(R20.991).当Fc14的浓度大于2 mmol/L时,电化学氧化过程以扩散控制为基本特征;当浓度小于0.2 mmol/L时,电极吸附现象的特征趋于明显.与此同时,Ipc和扩散系数(D)在Fc14的临界胶束浓度(CMC)附近出现突变,这与Fc14表面张力变化趋势相吻合.     

Octadecyltrimethylammonium surfactant-immobilized cation exchange membranes for solid-phase extraction of phenolic compounds

In this study, octadecyltrimethylammonium surfactant was immobilized onto a cation exchange membrane for the application in solid-phase extraction of phenolic compounds. The results indicate that an HCl prewashing step and the use of hydroxide (or methoxide) counter ion could greatly improve the immobilized surfactant capacity. Through elemental and thermogravimetric analyses, the resulted immobilization percentage on the membrane (compared to membrane ion exchange capacity) was about 50, 100, and 150%, respectively, for the feed surfactant amount of 150, 2000, and 5000 μmol (volume = 20 mL). Phenol, 4-nitrophenol, 2,4-dimethylphenol, 2,4-dichlorophenol, 4-chloro-3-methylphenol, and bisphenol A were the tested compounds in a breakthrough volume experiment. The order of the obtained breakthrough volume values is similar to that of K_ow values of the phenolic compounds. In the solid-phase extraction process from a feed mixture of 0.1 ppm for 4-nitrophenol, 2,4-dichlorophenol, and 4-chloro-3-methylphenol, high concentration factors and almost complete recoveries were achieved. Moreover, by increasing the membrane volume, a larger sample volume could be processed without any deterioration in performance.     

TritonX-100 selective chemosensor based on β-cyclodextrin modified by anthracene derivative

β-Cyclodextrin (CD) modified by 2-(9-anthracenecarboxamido)phenyl group (Ant-CD) was synthesized and their complexation behavior was investigated by UV and fluorescence spectroscopy. Fluorescence intensity of Ant-CD was dramatically enhanced ca. 10-fold by the addition of TritonX-100 (TX-100) in water below the critical micelle concentration. Ant-CD also showed ca. 4-fold fluorescence increasing in the addition of analogous materials, n-octylbenzenesulfonate in water. These results indicate that Ant-CD can act as a highly sensitive and selective chemosensor for TX-100. Ant-CD and TX-100 formed a pseudorotaxane supramolecular complex. This result was supported by ¹H-¹H NOESY NMR measurement.     

A label-free differential proteomic analysis of mouse bronchoalveolar lavage fluid exposed to ultrafine carbon black

Ultrafine carbon black (ufCB) is a potential hazard to the lung. It causes changes in protein expression and it increases alveolar-capillary permeability in the lung. Label-free quantitative proteomic methods allow a sensitive and accurate analytical method for identifying and quantifying proteins in a protein mixture without chemically modifying the proteins. We used a label-free quantitative proteomic approach that combined and aligned LC-MS and LC-MS/MS spectra to analyze mouse bronchoalveolar lavage fluid (BALF) protein changes associated with exposure to ufCB. We developed a simple normalization method for quantification without spiking the internal standard. The intensities of unchanged peptides were used as normalization factors based on a statistical method to avoid the influence of peptides changed because of ufCB. LC-MS/MS spectra and then database searching were used to identify proteins. The relative abundances of the aligned peptides of identified proteins were determined using LC-MS spectra. We identified 132 proteins, of which 77 are reported for the first time. In addition, the expression of 15 inflammatory proteins and surfactant-associated proteins was regulated (i.e., 7 upregulated and 8 downregulated) compared with the controls. Several proteins not previously reported provide complementary information on the proteins present in mouse BALF, and they are potential biomarkers for the understanding of mechanisms involved in ufCB-induced lung disorders hypothesize that using the label-free quantitative proteomic approach introduced here is well suited for more rigorous, large-scale quantitative analysis of biological samples. We hypothesize that this label-free quantitative proteomic approach will be suited for a large-scale quantitative analysis of biological samples.     

ZnIn_2S_4的制备及其表面活性剂辅助的形貌控制生长

采用湿化学合成路线以巯基乙酸为包覆剂,水为溶剂制备了六方相ZnIn2S4。应用能谱分析(EDS)、X射线衍射(XRD)、透射电镜(TEM)、扫描电镜(SEM)和紫外-可见光谱对产物的组成、结构、形貌和光学性质进行了表征。结果表明,所得到的ZnIn2S4具有层状形貌。这些层状物是由ZnIn2S4纳米粒子前驱体在热处理过程中聚集生长而成的。另外,以ZnIn2S4纳米粒子前驱体为起始原料,借助表面活性剂的导向作用在固/液界面成功地实现了ZnIn2S4的形貌控制生长,得到了具有棒状、棒簇状、管簇状形貌的ZnIn2S4。根据实验结果,初步讨论了可能的表面活性剂辅助的ZnIn2S4形貌控制生长的机制。     

One Pot Synthesis of Amphiphilic Hyperbranched Poly-(amino ester)and Its Dynamic Surface Activity

Amphiphilic hyperbranched poly(amino ester)s with hydrophilic multi‐ethoxylated triacrylate backbone and hydrophobic long alkyl side chain were firstly synthesized via one pot Michael addition polymerization. The poly‐(amino ester) could dissolve in cold water and self‐assemble into loose micelle. Under 50–1000 ms bubble, the dynamic surface tension (DST) of the poly(amino ester) aqueous solution (0.5 wt%) still maintained in the range of 32–28 mN/m. The aqueous solutions of poly(amino ester)s with different molecular weights showed the lower critical solution temperature (LCST) in the range of 8–50°C, which could also be tuned by its pH. Capped with hydrophobic groups on the terminal units and partially neutralized with acid, the poly(amino ester)s still kept their stable dynamic surfactant behaviors, indicating promising application.