偶联阳离子表面活性剂和常用阴离子表面活性剂混合溶液的相分离和微观结构

The properties of aqueous two-phase system (ATPS) of mixed solution containing gemini cationic surfactant trimethylene-l,3-bis(dodecyldimethyl ammonium) bromide (12-3-12, 2Br-) and traditional anionic surfactant sodium dodecyl sulfate (SDS) with or without added salt have been studied. An ATPS is formed in a narrow region of the ternary phase diagram different from that of traditional aqueous cationic-anionic surfactant systems. In ATPS region, the lowest total concentration of surfactants varies with the mixing ratio of geminis to SDS. Photographs obtained from freeze-etching, negative-staining and transmission electron microscopy show that the microstructures of two phases are different from each other. Micelles and vesicles can coexist in a single phase. The addition of salts can change the phase diagram of ATPS. Furthermore, the added salts promote the aggregation of rod-like micelles to form coarse network structure that increase the viscosity of solutions. The negative ions of the added salts are the determining factor.     

碳毡基体电活性铁氰化镍电极电控离子交换连续分离Cs~+(英文)

Nickel hexacyanoferrate (NiHCF) film was synthesized on porous three-dimensional carbon felt (PTCF) substrate by repetitious batch chemical depositions, and the NiHCF/PTCF electrode was used as electrochemically switched ion exchange (ESIX) electrode in a packed bed for continuous separation for cesium ions. The morphologies of the prepared electrodes were characterized by scanning electron microscopy and the effects of solution concentration on the ion-exchange capacity of the electrodes were investigated by cyclic voltammetry technique. Cycling stability and long-term storage stability of NiHCF/PTCF electrodes were also studied. The NiHCF/PTCF electrodes with excellent ion-exchange ability were used to assemble a diaphragm-isolated ESIX reactor for cesium separation. Continuous separation of cesium and regeneration of NiHCF/PTCF electrode based on the diaphragm-isolated reactor were performed in a laboratory-scale two-electrode system.     

SEBS三嵌段共聚物膜的形态研究

Surface morphologies of the films of poly [styrene-b-（ethylene-co-butene）-b-styrene] （SEBS） have been studied by using tapping-mode atomic force microscopy （TM-AFM）. The films of block copolymer were prepared both by spin-coating on mica and by solvent-casting on different solution surfaces. For spin-coating samples, the effect of solution concentration, solvent, and annealing temperature are investigated. It is shown that changing the concentration of the solution makes no difference on the morphology of the film of the block copolymer. The microstructures are quite stable during thermal annealing; only the size of the domains changes toward the equilibrium configuration. However, solvent annealing can notably change the microstructures. When different selective solvents are used for film spin-coating, different morphologies can be obtained and explained by the different solubility parameters of the solvents. As expected, significant different morphologies in the top and the bottom surfaces of the casting films were observed. The images of the top surfaces reveal cylinder microdomains, while those of the bottom surfaces were spherical morphologies.     

鼓泡塔中低浓度表面活性剂对CO2吸收传质系数的影响（英文）

The effect of different surfactants (n-octyltrimethylammonium bromide (OTABr), sodium dodecyl benzene sulfonate (SDBS) and Tween 80) with different critical micelle concentrations (CMC) on the CO2 absorption into aqueous solutions in a bubble column is analyzed in the present work. The presence of these surfactants in-creased the gas–liquid interfacial area, and decreased the liquid phase mass transfer coefficient, but with signif-icant different extent. The results indicated that the CMC can be a key parameter affecting the mass transfer of CO2 absorption into a dilute aqueous solution of a surfactant. Sardeing's model was used to fit the experimental data successfully by re-correlating the parameters.     

Structure,characterization, and dynamic performance of a wet air oxidation catalyst Cu–Fe–La/γ-Al_2O_3

A Cu–Fe–La/γ-Al_2O_3(CFLA) catalyst was prepared by the excessive impregnation method and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results indicate that the catalyst contained mostly Cu~(2+), Fe~(3+), and La~(3+)and a small amount of Cu~+, Fe~(2+), and La. The active components were uniformly distributed in the catalyst, and the particle size of the components was approximately 7.5 nm. The CFLA catalyst was used for the treatment of methyl orange(MO) solution by catalytic wet air oxidation(CWAO), and it exhibited a high catalytic activity. The catalytic reaction involved variable valence states of metals and free-radical reaction mechanism. The CWAO reaction of MO solution was fitted by a segmented first-order dynamic model, and the rapid reaction apparent activation energy was 13.9 k J·mol~(-1).     

任意可调Zn-Co合金镀层的电沉积

The effects of pulse parameters on the cobalt content, surface morphologies and grain size of Zn-Co alloy deposits were studied using a pulse plating technique with a square-wave current containing reverse pulse. Average current density and reverse anodic current density amongst the variables investigated have very strong effects on the cobalt content in the Zn-Co alloy deposits. Grain size, surface appearance and internal stress in the deposit were improved significantly by introducing the reverse current. Varieties of Zn-Co alloy compositionally modulated multilayer (CMM) coatings with large differences in cobalt contents for different sublayers were electrodeposited by designing corresponding waveforms using a computer-aided pulse plater and characterized in terms of surface morphologies. Cross-sectional morphologies of the Zn-Co alloy CMM coatings, examined using field emission gun scanning electron microscopy (FEGSEM), confirmed the layered structure.     

Influence of monovalent alkaline metal cations on binder-free nano-zeolite X in para-xylene separation

The adsorption process was studied for separating para-xylene from xylene mixture on modified nano-zeolite X in a breakthrough system. Nano-zeolitic adsorbent with different ratios of SiO2/Al2O3 was synthesized through hydrothermal process and ion-exchanged with alkaline metal cations like lithium, sodium and potassium. The product was characterized by X-ray diffraction, scanning electron microscopy (SEM), nitrogen adsorption, transform electron microscopy (TEM) and in situ Fourier transform infrared (FTIR) spectroscopy. The influence of nano-zeolite water content and desorbent type on the selectivity of para-xylene toward other C8 aromatic isomers was studied. The optimization of adsorption process was also investigated under variable operation conditions. The isotherm for each isomer of C8 aromatics and the desorbents possess the adsorption characteristics of Langmuir type. The selectivity factor of para-xylene relative to each of meta-xylene, ortho-xylene and ethylben-zene under the optimum conditions obtained to be 5.36, 2.43 and 3.22, in the order given.     

Electrocatalytic Activity of Ti/TiO2 Electrodes in H2SO4 Solution

Ti/TiO2 electrodes were prepared with the polymeric precursor method (PPM). The structure and morphology of Ti/TiO2 electrodes were examined with XRD and ESEM. The voltammetric charge (q*) of Ti/TiO2 electrodes as cathode in 0.5 mol/L H2SO4 solution was investigated with cyclic voltammetry. It was found that the electrocatalytic activity of the Ti/TiO2 electrodes was affected by the structure and morphology of the Ti/TiO2 electrodes, in other words, was affected by the calcination conditions of preparing the electrodes. The value of q*in was considerably larger than that of q*out, which means that the ‘inner’ active surface area was much larger than the ‘outer’ active surface area, and ‘inner’ active surface played a main role in the electrocatalytic activity of the Ti/TiO2 electrodes.     

磺化聚醚砜/纳米TiO2复合超滤膜制备及其抗污染机理

Membrane fouling is one of the major obstacles for reaching a high flux over a prolonged period of ultrafiltration (UF) process. In this study, a sulfonated-polyethersulfone (SPES)/nano-TiO2 composite UF membrane with good anti-fouling performance was fabricated by phase inversion and self-assembly methods. The TiO2 nanoparticle self-assembly on the SPES membrane surface was confirmed by X-ray photoelectron spectroscopy (XPS) and FT-IR spectrometer. The morphology and hydrophilicity were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle goniometer, respectively. The anti-fouling mechanism of composite UF membrane was discussed through the analysis of the micro-structure and component of UF membrane surface. The results showed that the TiO2 content and the micro-structure of the composite UF membrane surface had great influence on the separation and anti-fouling performance.     

Effect of Liquid-phase Oxidation Impurities on Solubility of Water in Hydrocarbon Fuels

The effect of liquid-phase oxidation impurities on the solubility of water in hydrocarbon fuels was studied.The results show that the concentration of polar surfactant molecules in the first region increases(true solution)during fuel oxidation,and since the oxidation groups(-COOH,-O=O,-OH,etc.)have similar dipole momentμ,the dielectric loss tangent tanδincreases linearly in this region with surfactant concentration.Upon further oxidation,micelle structures begin to form at a certain point.Micelle formation leads to a sharp decrease in the dipole moment attributable to the monomer unitμ/n,where nis the number of molecules in a micelle.A several-fold decrease in the dipole moment leads to a sharp drop in tanδ.Upon further increase in the number and size of micelles,the dipole moment remains practically unchanged,and the dielectric loss tangent begins to increase linearly again with surfactant concentration.If the critical concentration for micelle formation is achieved upon further oxidation of hydrocarbon liquids,micelle formation processes occur spontaneously in the solution,and the true solution becomes a colloidal system(sol).The resulting micelles are structured with hydrocarbon radicals of molecules toward the outside and hydrophilic(polar)groups toward the inside.Water molecules are located inside micelles and held so securely that water molecules do not aggregate as temperature decreases.The reason for significant differences in the equilibrium solubility of water in hydrocarbon fuels is the different oxidation factors of product samples,resulting from the accumulation of various concentrations of oxidation products,which are natural surfactants,in hydrocarbon fuels.     

复合电沉积制备TiO_2/泡沫镍光催化材料及其催化活性

采用复合电沉积方法制备了TiO2/泡沫镍光催化材料,通过扫描电子显微镜（SEM）和能量色散谱（EDS）分别对纳米复合镀层进行了形貌和成分表征,同时研究了在镀液中添加不同表面活性剂对光催化材料镀层的影响。讨论了TiO2/泡沫镍光催化材料对大肠杆菌和小球藻的光催化活性。结果表明：在本实验的电沉积工艺条件下,泡沫镍基底上获得了微粒分布均匀、Ti的质量分数为5.97%的纳米TiO2-Ni复合沉积层。添加了阴离子表面活性剂的光催化材料表面TiO2颗粒具有良好的分散性。TiO2/泡沫镍光催化材料处理含大肠杆菌水样,反应30 min灭活率达到60.1%,反应2 h灭活率达到99.9%;处理水中的小球藻溶液,初始3 h内,小球藻溶液中所含叶绿素a从初始的98.2 mg/m3降至38.2 mg/m3。     

电压对钛阳极氧化薄膜形貌的影响

采用两步施加电压的阳极氧化方法制备了具有不同形貌的氧化钛薄膜,使用扫描电子显微镜对在不同初始电压、不同放电电压下制备的氧化钛薄膜的形貌进行了分析。结果表明,在相同的放电电压下,通过改变初始电压可以制备出具有不同平均孔径和平均孔密度的阳极氧化钛薄膜;在一定的初始电压下,放电电压有一定的极限值,超过这个极限值电极将被烧毁;在初始电压60V,放电电压140V条件下制备的阳极氧化钛薄膜的纳米孔最规整、分布最均匀、孔径最均一。     

不同后处理方法制备纳米复合材料Ag/TiO2-ZrO2及其微波辅助光催化甲基橙

采用P123(EO20PO70EO20)作模板剂,通过溶胶-凝胶-程序升温溶剂热一步法,并经煅烧和萃取两种不同的后处理方法制备了一系列具有光催化活性的纳米复合材料Ag/TiO2-ZrO2。经XRD、XPS、TEM、N2吸附-脱附测定测试手段对不同钛锆比例和不同后处理获得样品的组成、结构及形貌等进行了对比分析,获得了最佳光催化材料Ag/TiO2-ZrO2-C(3∶1)。该复合材料结晶度高、结构规整、呈四方体形、颗粒分布均匀,具有较均匀的孔结构,其银以单质形式存在,且均匀分散在TiO2-ZrO2表面。通过微波辅助光催化降解染料甲基橙的实验,对不同处理方法所获Ag/TiO2-ZrO2的光催化活性进行了探究。实验结果表明,通过煅烧后处理方法得到的催化剂具有最好光催化活性,在90 min内降解率高达94.0%,其活性高于市售P25、TiO2-ZrO2和Ag/TiO2-ZrO2-E(3∶1)。     

Transesterification reactions over morphology controlled amino-functionalized SBA-15 catalysts

The amino-functionalized SBA-15 (NH₂-SBA-15) catalysts have been synthesized by different approaches such as direct co-condensation, prehydrolysis of sodium metasilicate, and post synthetic-grafting methods in order to get different morphologies by using the amphiphilic triblock copolymer, pluronic P123 as a surfactant and 3-aminopropyltriethoxysilane (APTES) as a precursor of functional groups under a strong acidic condition. The functionalized materials were confirmed with X-ray diffraction (XRD), N₂ gas adsorption/desorption studies, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and the amount of amino-groups was evaluated by TGA analyses. Catalytic transesterification reactions of diethylmalonate with various aliphatic and aromatic alcohols were investigated over the amino-functionalized SBA-15 catalysts. Among the functionalized catalysts, the material synthesized via direct co-condensation method which had short channeled hexagonal platelet morphology exhibited enhanced catalytic activities with normal aliphatic alcohols than other fibrous type catalysts. The activities of the catalysts were found to be very much dependent on morphologies, dispersion of amino groups and molecular shape of alcohols.     

强碱-阳极氧化法处理Ti片制备TiO_2薄膜的研究

本文利用强碱-阳极氧化法对钛片进行改性,制备TiO2薄膜;用扫描电镜（SEM）、X射线光电子能谱（XPS）考察了不同电解液浓度下氧化电压对TiO2氧化膜形貌及组成的影响。结果发现,在本实验条件下,该法制得的氧化膜是由三种钛氧化物组成的,主要成分是TiO2,此外还有低价钛氧化物Ti2O3及TiO;氧化电压的不同会对薄膜形貌产生重要的影响,当氧化电压较高时,氧化膜的厚度比较厚且致密;钛表面生成氧化膜大致过程可概括为：Ti→TiO→Ti2O3→TiO2,其中TiO转为为TiO2的几率依靠电势的大小及氧化时间的长短。     

Hydrogen peroxide sensors for cellular imaging based on horse radish peroxidase reconstituted on polymer-functionalized TiO₂ nanorods

We describe the reconstitution of apo-horse radish peroxidase (apo-HRP) onto TiO(2) nanorods functionalized with a multifunctional polymer. After functionalization, the horse radish peroxidase (HRP) functionalized TiO(2) nanorods were well dispersible in aqueous solution, catalytically active and biocompatible, and they could be used to quantify and image H(2)O(2) which is a harmful secondary product of cellular metabolism. The shape, size and structure of TiO(2) nanorods (anatase) were analyzed by transmission electron microscopy (TEM), high resolution TEM (HRTEM), electron diffraction (ED) and X-ray diffraction (XRD). The surface functionalization, HRP reconstitution and catalytic activity were confirmed by UV-Vis, FT-IR, CLSM and atomic force microscopy (AFM). Biocompatibility and cellular internalization of active HRP reconstituted TiO(2) nanorods were confirmed by a classical MTT cytotoxicity assay and confocal laser scanning microscopy (CLSM) imaging, respectively. The intracellular localization allowed H(2)O(2) detection, imaging and quantification in HeLa cells. The polymer functionalized hybrid system creates a complete sensor including a "cell positioning system" in each single particle. The flexible synthetic concept with functionalization by post-polymerization modification allows introduction of various dyes for sensitisation at different wavelengths and introduction of various anchor groups for anchoring on different particles.     

多孔二氧化钛微管的制备及表征

以2种不同的方法制备了多孔二氧化钛微管。一种是在不使用任何模板的条件下,以冰乙酸为分散剂,将四氯化钛在氨水中水解制备出了具有锐钛矿晶型结构的二氧化钛多孔微管。另一种是以脱脂棉为模板,以钛酸四丁酯为前躯体,制备出了锐钛矿晶型的二氧化钛微米管。采用X射线衍射（XRD）,扫描电子显微镜（SEM）,透射电子显微（TEM）等手段对其进行了表征,从而对样品的微观结构、颗粒形态、分布情况、管径、管壁、晶型以及物相组成等方面进行检测。     

空心钛酸钡的制备及其形成机理

以二氧化钛（TiO₂）和八水合氢氧化钡[Ba（OH）₂·8H₂O]为原料,采用水热合成法,成功制备出具有四方相晶型和空心形貌结构的钛酸钡粉体。利用透射式电子显微镜（TEM）和X射线衍射（XRD）对样品的形貌结构和晶型做了表征,通过研究反应过程中钛酸钡粉体的结构和晶型随时间的变化过程,对空心钛酸钡的形成机理做了详细的探讨,并考察了不同反应温度和钡浓度对钛酸钡粉体结晶和生长的影响。研究结果表明：反应温度和钡浓度会影响钛酸钡粉体的晶型和形貌,并以此提出了一种空心钛酸钡的形成机理;当反应温度为180 ℃、钡浓度为3.0 mmol/L时,能获得粒径分布均匀的四方相晶型的空心钛酸钡粉体。     

微乳液法制备纳米TiO2/活性炭复合体的研究

纳米TiO2是一种高效的光催化剂,而光催化剂的制备和固化是光催化技术应用的关键。采用油酸/正丁醇/NaOH溶液制备了纳米TiO2/活性炭复合材料。用微乳体系制备出纳米二氧化钛前驱体,然后由表面活性剂稳定和保护的纳米粒子在氢键吸附等作用力下包覆于活性炭载体的表面。用热重-差热分析、扫描电镜、红外光谱法对其结构进行分析。结果表明:所制得TiO2粒径为20 nm左右,呈球形分布于活性炭表面。用分光光度法测得TiO2的包覆率为28.2%。     

SiO2表面上制备纳米TiO2中水量对TiO2含量和形貌的影响

利用吸附相反应技术在SiO2表面原位制备了纳米TiO2,研究水的加入量对TiO2粒子制备的影响。用分光光度法测定乙醇体相中Ti含量随反应时间的变化,发现Ti含量呈现先快后慢的变化趋势,且水量在1．0～1．1ml。时Ti含量出现急剧变大。Ti含量的这一突变区域通过电子色散能谱仪对载体SiO2表面Ti含量的测定得到了进一步地确定。由透射电子显微镜观察到SiO2表面TiO2粒子存在着两种不同的形貌：覆盖在SiO2表面黑色区域和直径在1nm左右的单一小粒子。X射线衍射分析表明：TiO2晶粒粒径随着水量的增加而变大。实验结果发现：在不同的水量下,钛酸丁酯能够与吸附层和乙醇体相中的水以及SiO2表面羟基发生水解缩合反应。3种反应的不同反应速率导致了Ti含量曲线中的不同斜率,另外钛酸丁酯在醇体相中的水解也导致体系中Ti含量的急剧变大。