紫杉醇分子印迹聚合物的制备及其吸附性能

采用分子印迹技术,以紫杉醇为模板分子,2-乙烯基吡啶(2-VP)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,在氯仿中制备了紫杉醇分子印迹聚合物.用紫外光谱法对紫杉醇和功能单体的相互作用进行了分析,通过平衡结合法和Scatchard模型评价了印迹聚合物的吸附特性.结果表明,紫...     

紫杉醇分子印迹聚合物的制备及其吸附性能

采用分子印迹技术,以紫杉醇为模板分子,2-乙烯基吡啶(2-VP)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,在氯仿中制备了紫杉醇分子印迹聚合物。用紫外光谱法对紫杉醇和功能单体的相互作用进行了分析,通过平衡结合法和Scatchard模型评价了印迹聚合物的吸附特性。结果表明,紫杉醇与2-VP在氯仿中形成了稳定的1∶2主客体配合物,该印迹聚合物对紫杉醇呈现出高特异性吸附。Scatchard分析表明,印迹聚合物中形成了一类等价的结合位点,结合位点的平衡离解常数和最大表观结合量分别为29.89 mg/L和5.66 mg/g。     

碳纳米颗粒增敏的分子印迹电化学传感器检测阿奇霉素的研究

以磺化沥青(sulfonsted bitumen, SP)作为碳源,通过纯化和高温碳化法制备碳纳米颗粒(carbon nanoparticles, CNPs),将CNPs分散在壳聚糖(chitosan, CS)溶液中,并用滴涂法修饰在金电极(Au)上来得到CNPs-CS/Au。以阿奇霉素(azithromycin, AZM)为模板分子、多巴胺(dopamine, DA)为功能单体,利用电聚合法在CNPs-CS/Au电极上制备了AZM分子印迹薄膜,构建了高灵敏度且专一性识别AZM分子的电化学传感器(MIP/CNPs-CS/Au)。分别采用扫描电镜(scanning electron microscope, SEM)、X-射线衍射(X-ray diffraction, XRD)、X-射线光电子能谱(Xray photoelectron energy spectroscopy, XPS)、循环伏安法(cyclic voltammetry, CV)、电化学阻抗法(electrochemical impedance method, EIS)和差示脉冲阳极溶出伏安法(differential pu...     

一维纳米结构ZnO的制备

采用溶胶-凝胶法,以醋酸锌(Zn(CH3COO)2.2H2O),草酸((COOH)2.2H2O)和无水乙醇为原料,制备得到了粒子直径在30 nm左右、粒度分布均匀、分散性较好的球状纳米ZnO粒子.以上述反应为基础,在反应体系中加入一定量的有机添加剂三乙醇胺,得到了棒状结构的纳米ZnO.利用透射电子显微镜(Transmission Electron Microscopy,TEM)研究了有机添加剂三乙醇胺的加入对产物纳米ZnO形貌的影响.实验结果表明:有机添加剂三乙醇胺在棒状纳米ZnO的形成过程中起决定性作用,并且所形成的棒状纳米ZnO的形貌随添加剂用量的不同而不同,所以调节三乙醇胺的加入量可以有效地控制纳米ZnO的形貌.     

纳米TiO2的制备及其光催化降解茜素红的研究

以钛酸丁酯为原料，采用溶胶-凝胶法成功制备了纳米TiO2粉末，用X射线衍射（XRD）对其进行了表征，并对影响其制备过程的因素进行了研究，讨论了不同焙烧温度对其光催化降解茜素红的影响。XRD结果显示，产物为锐钛矿型TiO2，其粒径为30．3nm，锐钛矿型TiO2的光催化活性明显高于金红石型TiO2，锐钛矿型向金红石型转变的临界温度在600～700℃之间。当焙烧温度为500℃时，其光催化降解茜素红效率最高，可达93％以上。     

采用浸渍-还原法在炭纤维表面制备纳米镍催化剂颗粒

为了在炭纤维表面原位生长纳米炭纤维／纳米碳管，研究它对炭／炭复合材料微观界面结构和导热性能的影响，以硝酸镍为催化剂前驱体，H2为还原气体，N2为载气，采用浸渍-还原技术在炭纤维表面制备纳米Ni催化剂颗粒。用扫描电镜观察Ni颗粒形貌和粒径，分析讨论还原温度和时间对纳米Ni颗粒的影响及纳米颗粒的形成原因。研究结果表明：随着还原温度升高，Ni颗粒逐渐变大；随着还原时间增加，催化剂前驱体涂层先分裂，再逐渐形成纳米Ni颗粒，而后又因烧结变大；H2和N2气在Ni颗粒形成过程中还起到刻蚀涂层、吸附弱化颗粒间粘结力的作用；合成纳米Ni颗粒的最佳工艺条件是：还原温度为400-450℃，还原时间为30～60min。     

溶胶-凝胶法制备纳米钛酸钡

以溶胶-凝胶法制备纳米钛酸钡粉体,利用价廉的重晶石为主要原料制备钡源,有效地克服了传统方法因采用有机钡盐或有机钛而导致的生产成本过高的缺点:研究结果表明,该方法可制备出高纯钛酸钡粉体,制备过程中三废排放物中基本不含有害物质,并可从母液中回收质量较高的副产品硝酸铵,具有产品质量高,原料来源广泛、价格低廉、工艺环保、节能等特点.     

纳米A12O3颗粒的制备及其悬浮液的分散稳定

以异丙醇铝为原料，甲苯为溶剂，氨水为pH值调节剂，采用溶胶-凝胶法制备了含有α和θ2种晶型的高纯纳米A12O3颗粒．产物经XRD，TEM以及BET测定和杂质含量分析，研究了不同pH值、分散剂种类及其用量对A12O3悬浮液分散稳定性的影响．研究结果表明：产物的主晶相是θ，次晶相是α；A12O3颗粒粒径为10～20nm，粒子呈球形或类球形，粒子尺寸分布较均匀，比表面积为82．31m^2／g；纯度≥99．95％；配制稳定的A12O3 CMP浆料的合适工艺条件为：在A12O3固含量为6％的浆料中，加入质量分数为10％的H2O2作为氧化剂，体积分数为0．99％的异丙醇胺作为分散剂，同时将浆料的pH值控制在3～4，能得到长时间不沉降的稳定浆料．     

辐射接枝聚丙烯纤维制备蛋白质分子印迹聚合物水凝胶

以聚丙烯(PP)纤维无纺布为基体,以丙烯酰胺为功能单体,以N,N'-亚甲基双丙烯酰胺为交联剂,采用辐射接枝的方法制备了纤维基牛血清白蛋白(BSA)分子印迹聚合物水凝胶,并用红外光谱仪对接枝聚合物进行了表征.结果表明,聚丙烯酰胺水凝胶被成功接枝到PP纤维上;印迹和非印迹聚合物的动力学和热力学吸附数据表明,印迹聚合物对蛋白质的吸附量明显大于非印迹聚合物的吸附量.接枝率随单体浓度的增加而增大,在单体质量分数为20%时,接枝率达到稳定值;接枝率随交联剂浓度的增加先增大后减小,当交联剂质量分数为2%时,接枝率达到最大值.     

溶胶-凝胶法制备纳米钛酸铅的工艺

采用无机溶胶-凝胶的方法来制备纳米钛酸铅粉体,以廉价的无机钛盐为原料,有效克服了传统方法因采用有机钛盐或有机钛而导致的生产成本过高的缺点,并利用XRD、FT-IR、SEM等分析手段对样品的颗粒大小、结构和形貌进行了表征.研究结果表明:制备出的PbTiO3干凝胶在1 000℃下热处理2 h可以得到结晶程度很好的纳米PbTiO3粉体.     

PAEs同分异构体双模板分子印迹聚合物的制备及性能

为高效去除液体中邻苯二甲酸酯（PAEs）,以邻苯二甲酸二（2-乙基）己酯（DEHP）为模板分子,邻苯二甲酸二正辛酯（DNOP）为辅助模板分子,二氧化硅改性磁性纳米四氧化三铁（Fe₃O₄@SiO₂）为载体,α-甲基丙烯酸（MAA）为功能单体,二甲基丙烯酸乙二醇酯（EGDMA）为交联剂,偶氮二异丁腈（AIBN）为引发剂,采用本体热引发聚合法制备吸附性能优于传统单模板分子印迹聚合物,且能对两种目标物质同时进行吸附的双模板分子印迹聚合物（D-MIPs）,并对其具体吸附性、选择性及再生性进行详细研究.结果表明:辅助模板分子DNOP的引入对DEHP的吸附性能起到优化促进作用;D-MIPs对于10种不同浓度DEHP的单位吸附量为0.49～6.16 mg/g,其单位吸附量与吸附速率均优于其单模板印迹聚合物（DEHP-MIPs）;两种模板分子均与所选单体之间存在多位点的协同作用;D-MIPs在30 min前可达到最佳吸附平衡状态;第5次的吸附容量为第1次的84.02%,且具有良好的再生性能.静态吸附过程拟合表明,聚合物体系更加符合单层特异性吸附的Langmuir吸附模型,D-MIPs与DEHP-MIPs对目标分子的吸附符合伪二级动力学过程;FT-IR红外光谱对印迹聚合物进行官能团表征证实聚合效果良好.     

磁性二氧化硅纳米粒子的制备及性能

为了克服磁性四氧化三铁纳米粒子易团聚、易氧化、耐酸性差等缺点,提高其在催化剂、靶向药物载体、生物分离、核磁共振成像、磁热疗等领域的利用效率,采用共沉淀法合成了四氧化三铁纳米粒子,然后以其为核用Stber法制备出二氧化硅包覆四氧化三铁的复合纳米粒子. 对包覆前及包覆后的磁性纳米粒子分别进行了X射线衍射、透射电子显微镜、振动样品磁强计的表征,并研究了二氧化硅的包覆对四氧化三铁纳米粒子磁性和耐酸性的影响. 实验结果表明:磁性四氧化三铁及磁性二氧化硅纳米粒子的粒径分别为约20 nm和40 nm;磁性四氧化三铁的磁饱和强度为5.7 emu/g,磁性二氧化硅纳米粒子的磁饱和强度也达到5.1 emu/g;此外,在稍微降低磁性的条件下,表面二氧化硅的包覆显著改善了四氧化三铁纳米粒子的分散性和耐酸性.     

双酚A分子印迹聚合物膜的制备与其性能研究

通过实验获得了双酚A分子印迹共混膜的相转化制备的工艺条件,并且研究了膜材料、铸膜液的组成和温度、分子印迹聚合物填充的情况、凝固浴的组成和凝固的温度、暴空时间以及膜的厚度等因素对膜的结构与性能的影响,对以此方法制备分子印迹膜提供了通用的理论指导。利用浓差推动渗透实验对所制备的共混膜进行了拆分机理分析,根据膜过程溶解一扩散原理建立了传质模型。实验结果表明,分子印迹共混膜对双酚A表现出了高度的识别性。     

Preparation and characterization of silica gel powders

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Selective recognition in molecularly imprinted polymer and its chromatographic characterization for cinchonine

A molecularly imprinting polymer (MIP) was synthesized via bulk polymerization under different conditions using anti-ague drug cinchonine (CN) as template. Infrared spectra (IR) results show that the template CN and functional monomer α-methyl acrylic acid (MAA) formed complexes before polymerization and the structure of complexes was simulated by Hyperchem. The results indicate that there are hydrogen bond or ionic bond between functional monomer and template molecule in acetonitrile solution. The MIP made in cold-initiated photo-polymerization has higher separation performance than that in the therm-initiated polymerization. The separation of the isomers CN and cinchonidine (CD) can be successfully obtained when its separate factor α reaches 1.82. Scatchard analysis suggests that the MIP recognizing CN with two classes of binding sites. The partition coefficient K _{d, 1} and apparent maximum number n _{max, 1} of binding sites with high affinity are 131.43 μmol/L and 58.90 μmol/g, respectively, while K _{d, 2} and n _{max, 2} of binding sites with low affinity are 2.32 mmol/L and 169.08 mmol/g, respectively. Foundation item: Project(2004035085) supported by the Postdoctoral Science Foundation of China; project(04JJ3080) supported by the Natural Science Foundation of Hunan Province     

Selective recognition in molecularly imprinted polymer and its chromatographic characterization for cinchonine

A molecularly imprinting polymer (MIP) was synthesized via bulk polymerization under different conditions using anti-ague drug cinchonine (CN) as template. Infrared spectra (IR) results show that the template CNand functional monomer α-methyl acrylic acid (MAA) formed complexes before polymerization and the structure of complexes was simulated by Hyperchem. The results indicate that there are hydrogen bond or ionic bond between functional monomer and template molecule in acetonitrile solution. The MIP made in cold-initiated photo-polymerization has higher separation performance than that in the therm-initiated polymerization. The separation of the isomers CN and cinchonidine (CD) can be successfully obtained when its separate factor α reaches 1.82. Scatchard analysis suggests that the MIP recognizing CN with two classes of binding sites. The partition coefficient Kd, 1 and apparent maximum number nmax, 1 of binding sites with high affinity are 131.43 μmol/L and 58. 90 μmol/g, respectively,while Kd, 2 and nmax, 2 of binding sites with low affinity are 2.32 mmol/L and 169.08 mmol/g, respectively.     

Nano-silica particles enhanced adsorption and recognition of lysozyme on imprinted polymers gels

Molecular imprinting technology has a great potential to be used in protein separation and purification.In this work,lysozyme imprinted polyacrylamide gel was prepared with silica particles as a sacrificial template to generate macro-porosity for fast adsorption.The adsorption equilibrium time and adsorption capacity were 9 h and 56 mg/g respectively,which was 2 h less and 2.3-fold more than polymers without the sacrificial template.In order to test molecular imprinting polymers(MIPs)'selectivity,bovine serum albumin(BSA)was chosen as interferent for binary adsorption tests.In addition,the adsorption selectivity was further investigated using different molar ratios of lysozyme to BSA with fixed total concentration of proteins,as well as using various total concentrations of proteins with an equimolar ratio of lysozyme to BSA.It has been proven that the total concentration of proteins should be larger than1.5×10~(-7) mol/mL,when the molar ratio of BSA to Lyz is 1∶1,in order to effectively separate Lyz from the binary protein mixture.The macro-porous lysozyme molecularly imprinted polymers have less adsorption time,larger adsorption capacity,and better imprinting effect.     

Facile and controlled synthesis of silica sol nanospheres through a modified sol-gel process

An effective and reproducible preparation of silica sol nanospheres via a modified sol-gel process has been described. Monodisperse and stable silica sol nanospheres with uniformsize were successfully obtained through the optimized synthesis in which the mixture of tetraethyl orthosilicate （TEOS） and ethanol was followed by the addition of water and ammonium hydroxide （NH3） separately, and the size of silica sol spheres was strictly controlled in the range of 25-119 nm with a narrow size distribution by fine adjustment of several reaction parameters. Results showed that in the presence of low concentration of TEOS, spheres size rose first and reached maximum when H2O concentration was up to 66 g/L. However, the diameter of silica sol spheres decreased above 66 g/L of H2O concentration. Furthermore, it was also found that the size and size distribution of silica sol nanospheres were affected by NH3 concentration. As NH3 concentration increased from 15 to 35 g/L, the diameter declined from 83 to 64 nm. Nevertheless, higher NH3 concentration would result in relatively broad size distribution, and gelation occurred when NH3 concentration reached 44 g/L. In addition, the effect of the different feed rates ofNH3 on the size growth of silica sol nanospheres was also discussed.     

分子印迹型CO_2吸附剂的改性及吸附性能研究

基于前期研究工作,通过同时提高模板分子比例和溶剂中添加甲苯的方法,改性分子印迹吸附剂,并通过N2吸附和红外光谱分析两种实验手段,对吸附剂的孔结构和表面官能团的情况进行了表征,对吸附剂改性前后的CO2的吸附性能进行了对比。实验结果表明,同时提高模板分子比例和添加甲苯溶剂的方法,增加了吸附剂的比表面积和表面胺基团密度,提高了吸附剂的吸附容量。本文同时研究了温度对吸附剂CO2的吸附性能的影响,结果表明,随着温度的增加CO2的吸附容量明显降低。     

温度响应性纳米介孔硅的制备、表征及其载药性能

以正硅酸乙酯、十六烷基三甲基溴化铵以及N-异丙基丙烯酰胺等为原料合成了一种新型的温度响应性介孔硅纳米粒,利用TEM、SEM、XRD、TG和氮气吸附脱附等温线对其结构进行了表征。结果表明:介孔硅微粒具有规则的介孔结构,温敏性物质N-异丙基丙烯酰胺成功嫁接于介孔硅表面。以红景天苷为模型药物,温度响应性介孔硅的载药率和包埋率分别为62.08μg/mg和31.04%。温度响应性介孔硅对红景天苷释放具有一定温度响应性。