17β-雌二醇乙酸纤维分子印迹复合膜的制备及性能研究

以多孔乙酸纤维膜为载体,17β-雌二醇为模板,采用紫外光引发制备了17β-雌二醇乙酸纤维分子印迹复合膜。试验对膜的选择吸附性和分离透过性进行了探讨。实验结果表明,所合成的乙酸纤维分子印迹复合膜对模板分子17β-雌二醇具有较好的选择吸附性,吸附量达10.2μmol/g;17β-雌二醇/17α-炔雌醇的分离因子为4.7。膜透过实验表明,该分子印迹复合膜能将17β-雌二醇与17α-炔雌醇分离开,表明17α-炔雌醇作为结构类似物在复合膜上的结合牢固性不如模板分子。     

PAEs硅胶表面分子印迹微球的制备及识别特性

用紫外分光光度法对功能单体和模板分子间的结合作用进行了研究,选择结合作用最强的甲基丙烯酸作为功能单体。用γ-甲基丙烯酰氧丙烯基三甲氧基硅烷对硅胶表面进行修饰,以邻苯二甲酸二甲酯作为模板分子,在硅胶表面聚合制备了邻苯二甲酸酯表面分子印迹聚合物微球(MIPMs)。用傅里叶红外和扫描电镜对产物进行了表征,吸附等温曲线实验选择了效果最好的正己烷作为溶剂,实验表明:MIPMs-模板分子在4h左右达到吸附平衡。Scatchard法分析了MIPMs-模板分子的吸附平衡常数(K)和吸附容量(Q),结果显示高吸附容量曲线Kd1=36.36mmol·L-1,Qmax1=33.58μmol·g-1;低吸附容量曲线Kd2=0.8850mmo·L-1,Qmax2=8.504μmol·g-1。选择性吸附实验结果表明MIPMs具有很好的选择性吸附能力。     

脲基功能化苯酚印迹聚合物的合成及其对苯酚的吸附研究

以苯酚为模板,γ-脲基丙基三甲氧基硅烷为功能单体采用表面分子印迹聚合法制备了脲基功能化的苯酚表面分子印迹聚合物(苯酚-MIP),并使用红外光谱对苯酚-MIP的结构进行了表征。结果表明:在最佳条件下,初始浓度c0=150mg/L,吸附时间t=20min,pH=7,温度T=30℃下,苯酚-MIP的吸附量是非印迹聚合物(NIP)的2.32倍。动力学数据拟合结果显示:苯酚在苯酚-MIP上的吸附符合伪二级动力学模型和Langmuir等温模型。另外,选择性实验结果显示:苯酚-MIP可以快速和选择性地吸附水中的苯酚。     

单一结合位点分子印迹聚合物的合成及性能

采用分子自组装印迹技术在光引发条件下制备了以(S)-布洛芬为模板分子,α-甲基丙烯酸为功能单体的分子印迹聚合物。通过红外对聚合物的结构进行了表征。透射电镜结果表明,交联剂用量对印迹聚合物的形貌特征具有显著的影响。同时结合Scatchard分析研究了印迹聚合物的吸附性能及选择性识别能力,表明印迹聚合物特异性吸附容量为41μmol/g,印迹指数为2.28,对(S)-布洛芬形成单一结合位点,且表现出明显的吸附选择性。     

L-苹果酸分子印迹聚合物微球的制备及性能评价

以L-苹果酸为模板分子,丙烯酰胺(AA)、乙二醇二甲基丙烯酸酯(EGDMA)分别为功能单体和交联剂,采用沉淀聚合法制备了分子印迹聚合物微球,研究了聚合体系组成对模板聚合物吸附特性的影响。实验表明,以1∶4∶20的物质的量比加入模板分子、AA和EGDMA时,制备的模板聚合物吸附容量高,印迹效果好。通过Scat-chard分析研究了聚合物的选择结合性能,结果表明分子印迹聚合物微球在识别L-苹果酸的过程中存在2类结合位点,而空白印迹聚合物微球只存在1类结合位点。印迹聚合物微球对L-苹果酸和D-苹果酸的手性分离因子α达2.05。     

盐酸二甲双胍磁性分子印迹聚合微球的合成

以盐酸二甲双胍为模板分子、Fe_3O_4为磁核、α-甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸酯为交联剂、偶氮二异丁腈为引发剂,采用表面印迹聚合法成功制备了对盐酸二甲双胍具有特异性识别功能的磁性分子印迹聚合微球。合成的磁性聚合物具有良好的磁响应,在外加磁场下可实现快速磁分离。红外光谱、X射线光电子能谱和扫描电镜结果证实聚合物为核壳结构,磁性粒子由硅烷偶联剂完全包覆,并在其表面形成了一层分子印记聚合物。静态吸附实验结果表明,制备的磁性分子印迹聚合物对模板分子盐酸二甲双胍具有良好的吸附能力,其饱和吸附量为83mmol/kg。以双胍类降糖成分盐酸丁二胍和盐酸苯乙双胍为竞争分子,磁性印迹聚合物对模板分子表现出良好的特异选择性。     

镉(Ⅱ)-乙二醛缩双邻氨基酚印迹聚合物的制备及其吸附性能

以Cd-乙二醛缩双邻氨基酚的配合物为模板分子,α-甲基丙烯酸(MAA)作为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,制备了镉-乙二醛缩双邻氨基酚的分子印迹聚合物。研究了该印迹聚合物对模板分子的吸附和选择性识别,并用火焰原子吸收法考察了溶液的浓度、温度和吸附时间等因素对聚合物吸附性能的影响。结果表明,印迹聚合物对模板分子具有较好的吸附性和选择性,吸附45 min达到平衡。     

醋酸纤维-奎宁分子印迹复合膜的制备及分离性能研究

采用多孔醋酸纤维膜为支撑体,制备了奎宁分子印迹复合膜,并对膜的选择结合性及分离性能进行了研究.研究结果表明,奎宁分子印迹复合膜对模板分子奎宁具有较好的选择结合性,奎宁在膜上结合量达到20.6μmol/g,奎宁/辛可宁的分离因子则为5.6;膜透过实验表明辛可宁透过奎宁分子印迹复合膜速率远大于奎宁的透过速率,该透过机理符合膜渗透的"溶解一扩散"模型.     

纳米SiO_2对阿魏酸分子印迹复合膜的影响研究

以PVDF微孔滤膜为支撑膜,纳米SiO_2为无机添加材料,阿魏酸为模板分子,α-甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,制备含纳米SiO_2的阿魏酸分子印迹复合膜。采用红外光谱测试证明了纳米SiO_2是以纯物理状态存在于聚合物印迹层中,通过平板超滤装置对改性膜的分离性能、水通量、接触角和承压能力进行了研究,结果表明,膜对阿魏酸仍然具有较高的分离性能,水通量和承压能力也比阿魏酸分子印迹复合膜有所提高。     

喜树碱分子印迹聚合物的计算机模拟及性能

采用计算机模拟的方法,通过Gaussian 03模拟喜树碱(CPT)分别与ɑ-甲基丙烯酸(MAA)或丙烯酰胺(AM)的复合物预组装构型,结果表明CPT与MAA形成的复合物更稳定。采用分子印迹技术,以CPT为模板分子,已二醇二甲基丙烯酸酯(EGDMA)为交联剂,MAA为功能单体,通过沉淀聚合法制备了CPT分子印迹聚合物微球。以吸附量及形貌为指标,确定了最佳合成条件:以30 mL甲醇/氯仿(8:2)为溶剂、模板分子/功能单体/交联剂的摩尔比为1∶4∶15时,分子印迹聚合物微球大小均匀,平均粒径约为0.3μm。所得聚合物通过等温、选择性吸附进行表征,结果表明该分子印迹聚合物微球对CPT具有良好的吸附能力及选择性,α和β值分别为2.49,3.09,吸附量为58.00μmol/g。     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Instructions & Forms for Authors

Journal of Materials Sciences ＆ Technology is a monthly journal for the rapid dissemination of new, impor- rant results in material and related fields. Submission Electronic files of MS Word and PDF are acceptable. Please visit http：//www.jmst.org and submit online.