纳米铁酸锌(ZnFe_2O_4)的表面改性

采用化学修饰方法,以二氧化硅为内层修饰材料,r-氨丙基三甲氧硅烷(APS)偶联剂为外层修饰材料,对磁性ZnFe2O4纳米粒子进行了双层修饰。并采用XRD、IR、Zeta电位对未包裹粒子,二氧化硅包裹的磁纳米粒子,APS和二氧化硅双层包修饰的纳米磁粒进行表征。同时也比较了三种粒子的耐酸性能。结果显示硅包裹的纳米磁粒Zeta电位明显向酸性方向移动,而双层的纳米磁粒Zeta电位向碱性方向移动。包裹的纳米磁粒在pH2.0的酸中具有很好的耐酸性能,而未处理的纳米粒子在酸溶液中发生了溶解。     

专利技术

专利：表面接枝有机功能分子的纳米二氧化硅及制备方法 本发明属于有机功能分子修饰的纳米二氧化硅领域,特别涉及到受阻酚类抗氧剂修饰的纳米二氧化硅及其制备方法。该方法通过氨基硅烷偶联剂作为桥联,将受阻酚类抗氧剂分子化学接枝到纳米二氧化硅上,其中氨基硅烷偶联剂占有机功能分子修饰的纳米二氧化硅总重量的3wt％～12wt％,     

纳米CuO/CoFe2O4-TiO2模拟太阳光降解亚甲基蓝的性能

采用溶胶-凝胶法制备CuO/CoFe2O4粒子,并与P25复合制备纳米催化剂CuO/CoFe2O4-TiO2.通过模拟太阳光催化降解亚甲基蓝,对催化剂活性进行研究,采用SEM、TEM、XRD和UV-Vis DRS方法对催化剂进行表征.结果表明,CuO/CoFe2O4粒子均匀分散在P25微粒表面,平均粒径为60 nm.并...     

丙烯腈系纤维

<正>20142099含有碳纳米管和钴铁氧体的静电纺纳米复合聚丙烯腈纤维Jin Xudong…;Polymer Composites,2012,33(3),p.317(英)用静电纺丝法制备含有碳纳米管(CNTs)和钴铁氧体(CoFe2O4)的纳米复合聚丙烯腈纤维。用水热法制备粒径为10~25 nm的CoFe2O4。X射线衍射的表征结果表明,CNTs和CoFe2O4成功地接枝到PAN基体上。扫描电子显微镜分析结果表明,纳米复合纤维具有规整的形态结构。透射电子显微镜分析结果表明,CNTs和CoFe2O4纳米粒子分散在PAN基体内部。制得的纳米复合纤维能够有效屏蔽     

PLA@MSNs纳米粒子的制备研究

选用十六烷基三甲基溴化铵(CTAB)为模板剂,以3-氨丙基三乙氧基硅烷(APTES)为氨基化硅烷化试剂,正硅酸四乙酯(TEOS)为硅源,均三甲苯(TMB)作为扩孔剂,在80℃下合成了具有氨基修饰的二氧化硅纳米粒子。通过在酸性醇溶液中回流去除模板获得氨基化的介孔二氧化硅(MSNsNH_2)。以MSNs-NH_2为引发剂,辛酸亚锡为催化剂,在高温、氮气氛围下通过丙交酯开环聚合生成表面聚乳酸(PLA)修饰的二氧化硅纳米粒子(PLA@MSNs)。实验通过傅里叶红外光谱、激光粒度仪等验证了纳米粒子的结构、粒径分布、Zeta电位,通过噻吩蓝(MTT)法证明了其细胞毒性较低。     

磁性纳米光催化剂TiO2/SiO2/CoFe2O4的制备与结构性能的研究

用层状前体法制备了尖晶石铁氧体CoFeO4.在其表面依次包覆SiO2和具有光催化活性的TiO2,制备出磁性纳米光催化剂TiO2/SiO2/CoFe2O4.用XRD、FT-IR和VSM等表征技术研究了磁核CoFe2O4和磁性光催化剂的结构与性能.利用催化剂光降解甲基橙评价了催化剂的活性.     

Co Fe2O4磁核硅胶纳米复合材料在化学分离/分析中的应用

Co Fe2O4磁核纳米复合材料的功能化制备是以钴铁氧纳米粒子作磁核,硅胶负载包裹制备得到磁硅胶纳米粒子,并进一步在此基础上功能化得到目标纳米复合材料。制备的钴铁氧磁核纳米复合材料在分析化学中的应用是近年来的研究热点之一。Co Fe2O4-Si O2纳米粒子的功能化主要包括氨基、巯基、酸基、甲基、金属氧化物、石墨烯、环糊精等。此外,也有少量报导包括多巴胺、抗体、血红蛋白等生物功能化负载Co Fe2O4-Si O2等。本文报导了最新Co Fe2O4磁硅胶纳米复合材料的功能化材料在化学分离/分析中的应用情况。     

纳米CoFe2O4的制备及其对PLA结晶性能的影响

为了实现聚乳酸(PLA)的功能化改性,将其进行改性探究PLA的结晶行为,采用了化学共沉淀法制备了油酸包覆的CoFe2O4纳米粒子,同时采用溶液浇铸法制备了PLA/CoFe2O4复合材料.使用傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)和X射线衍射仪(XRD)对CoFe2O4粒子及其复合材料的组成和结构进行分...     

硬脂酸对纳米Al2O3的有机表面修饰研究

为提高纳米α-Al2O3粒子在有机体系中的分散性和相容性,对纳米α-Al2O3进行了有机表面改性.首先制备了纳米α-Al2O3水分散液,然后把纳米Al2O3水分散液转移到溶有硬脂酸的正丁醇溶液中,升温到一定温度,将纳米Al2O3浆体中的水分蒸馏出去,使纳米Al2O3在有机相中进行表面改性,使得纳米Al2O3有机表面改性和防团聚处理一步完成,得到了团聚程度较小的纳米Al2O3粉体.采用红外光谱(IR)、热分析(TG-DTA)、透射电镜(TEM)、润湿性实验、分散性实验等手段对表面改性前后的纳米Al2O3进行表征.红外光谱和TEM表明,在纳米Al2O3表面包覆有硬脂酸的有机层,并且可能有硬脂酸铝的生成.热分析显示,包覆量约为16.7%.润湿性实验及分散性实验表明,经硬脂酸改性的纳米Al2O3的表面性质由亲水变为疏水.     

功能化Fe_3O_4纳米粒子去除水中Cu~(2+)的研究

本文通过水热法合成了Fe_3O_4磁性纳米颗粒,采用3-氨丙基三甲氧基硅烷(APTMS)对Fe_3O_4颗粒进行表面修饰,得到氨基化磁性微粒,并表征其性能。并用氨基化Fe_3O_4磁性纳米粒子构建铜离子吸附体系。实验结果表明,Fe_3O_4纳米粒子和功能化Fe_3O_4纳米粒子的磁饱和强度值(M)分别为78和59emu·g~(-1)。最终确定的最优工艺组合为:APTMS@Fe_3O_4添加量2mL,温度30℃,吸附时间15min。     

Covalent immobilization and characterization of Rhizopus oryzae lipase on core-shell cobalt ferrite nanoparticles for biodiesel production

Rhizopus oryzae lipase (ROL) was immobilized on the surface of silica coated amino modified CoFe2O4 nanoparticles and applied for biodiesel production.The results indicated more affinity of the ROL toward its substrate upon immobilization,as revealed by a lower Km value for the immobilized ROL compared to its free counterpart.Intrinsic fluorescence spectroscopy indicated a lower intensity for ROL immobilized on CoFe2O4 nanoparticles.Besides,immobilized ROL steady state anisotropy measurements presented lower values,which implied assembly of ROL molecules on magnetic nanoparticles upon immobilization as well as their restricted rotation upon covalent attachment.Thermal stability analysis revealed improved activity at higher temperatures for the immobilized enzyme compared to its free counterpart.Accordingly,Pace analysis to determine protein thermal stability revealed preservation of the protein conformation in the presence of increasing temperatures upon immobilization on nanoparticles.Finally,ROL immobilized on CoFe2O4 nanoparticles exhibited improved efficiency of biodiesel production in agreement with thermal activity profile.Therefore,the authors suggest application of the lipase mole-cules immobilized on CoFe2O4 nanoparticles for more efficient biodiesel production.     

Sulfonic Acid-Functionalized Silica-Coated Magnetic Nanoparticles as a Reusable Catalyst for the Preparation of Pyrrolidinone Derivatives Under Eco-Friendly Conditions

Silicon - The surface of silica-coated CoFe2O4 magnetic nanoparticles (CoFe2O4@SiO2), which is resistant to the oxidation due to silicone coating, was functionalized using chlorosulfonic acid and...     

正交试验优化核壳型Fe3O4@SiO2磁性复合微球的制备工艺

采用共沉淀法和溶胶-凝胶法制备了磁性Fe3O4纳米粒子及核壳型Fe3O4@SiO2复合微球,利用红外光谱(FTIR)技术测定了微球表面基团,证明了SiO2确实在Fe3O4纳米粒子的表面形成了包覆层。通过正交试验设计,利用激光粒度仪测量的微球粒径为指标,考察TEOS与磁性微球的体积比、反应温度、反应时间和乙醇浓度四因素对微球粒径的影响。结果表明TEOS与磁性微球的体积比为2、反应温度为80℃、反应时间为4 h,乙醇浓度为80%是制备大粒径Fe3O4@SiO2磁性复合微球的适宜条件。     

磁性纳米钌催化剂制备及其催化甲苯氢化反应性能

采用共沉淀法制备Fe₃O₄粒子,用SiO₂对Fe₃O₄纳米粒子进行表面包覆,用改性聚乙烯吡咯烷酮对所得磁性粒子进行表面修饰,制备磁性纳米粒子负载钌催化剂Ru/PVP-DB-171/SiO₂/Fe₃O₄。红外光谱、X射线衍射、扫描电子显微镜及透射电子显微镜分析表明,所得粒子结构是面心尖晶石结构,Fe₃O₄为核,无定形SiO₂为壳,纳米钌吸附在磁性载体表面。该粒子具有高分散性,可用磁分离实现固液分离。以甲苯液相催化加氢反应为模型,评价磁性负载钌催化剂的催化性能,计算出甲苯氢化的活化能为16.6 kJ·mol^-1,在433 K和4.0 MPa条件下,反应转换数达30 262 mol·(mol-Ru）^-1,Ru催化剂可循环使用8次,添加助剂的种类和数量影响催化剂活性。     

二氧化钛/铁酸钴磁性光催化材料的制备及表征

以化学共沉淀法制备的铁酸钴纳米粒子为磁核,采用硫酸氧钛水解法在铁酸钴磁性粒子表面包覆二氧化钛,制得顺磁性易于固液分离的二氧化钛/铁酸钴复合光催化材料,并运用X射线衍射（XRD）、透射电镜（TEM）和振动样品磁强计（VSM）技术进行了表征,以甲基橙为模拟污染物研究其光催化活性。结果表明：制备的复合光催化材料晶型较好,其中二氧化钛和铁酸钴分别以锐钛矿型和尖晶石结构存在,粒径为40～50 nm,且具有超顺磁性;二氧化钛/铁酸钴复合光催化材料具有较高的光催化活性同时具有良好的重复使用性能。     

Unique magnetic properties and magnetization reversal process of CoFe2O4 nanotubes fabricated by electrospinning

CoFe(2)O(4) nanotubes have been directly fabricated by single-capillary spinneret electrospinning. The external diameter of the CoFe(2)O(4) nanotubes ranges from 60 nm to 160 nm. The morphology and structure characterizations show that individual CoFe(2)O(4) nanotubes are made of CoFe(2)O(4) nanocrystals stacking along the nanotubes with no preferred growth directions and these individual nanocrystals are single crystal with a cubic spinel structure. Each nanocrystal was shown to be a single magnetic domain. The magnetic measurements show that the coercivity (H(c)) of the CoFe(2)O(4) nanotubes decreases from 10?400 Oe at 5 K to 300 Oe at 360 K. The CoFe(2)O(4) nanotubes have a spin reorientation (SR) at 5 K, which is different from CoFe(2)O(4) nanorods and nanoparticles. Based on the observed morphology and crystal structure, a micromagnetic model, "chain-of-rings", is developed to interpret the magnetic behavior of the CoFe(2)O(4) nanotubes. The theoretical coercivity (534 Oe) is in good agreement with the experimental results (509 Oe). It is believed that our work should open a new route to prepare various magnetic ferrite nanotubes and is significant for expanding the application of CoFe(2)O(4) into the new fields.     

Fe3O4/凹凸棒土磁性纳米复合材料的制备与表征

采用超声共沉淀法制备了Fe3O4-凹凸棒土(AT)磁性纳米复合材料,经红外光谱(FTIR),X射线衍射(XRD),场发射扫描电镜(FESEM),比表面积(BET)和振动样品磁强计(VSM)等方法进行表征.结果表明:Fe3O4纳米粒子较好地吸附在AT表面,并且表现出优良的吸附性能和顺磁性.     

Synthesis of patterned nanogold and mesoporous CoFe2O4 nanoparticle assemblies and their application in clinical immunoassays

Herein, we describe a facile and feasible synthesis method for patterning nanogold particles onto magnetic mesoporous CoFe(2)O(4) nanostructures (Au-MMNs) by using poly(vinyl pyrrolidone) (PVP) as cross-linker. Initially, mesoporous CoFe(2)O(4) nanoparticles were initially synthesized with a thermal decomposition method by using mesoporous silica nanoparticles as templates, and then nanometre-sized gold particles were produced through the in situ reduction of the Au(III) on the PVP-functionalized CoFe(2)O(4). The as-prepared Au-MMNs were characterized by transmission electron microscopy (TEM), N(2) adsorption-desorption isotherms, UV-visible adsorption spectrometer, vibrating sample magnetometer (VSM) and X-ray photoelectron spectroscopy (XPS). Furthermore, we also demonstrate the conjugation capacity of the synthesized Au-MMNs toward biomolecules by using quartz crystal microbalance (QCM), and the possible application in the electrochemical immunoassays. Experimental results indicated that the resulting Au-MMNs display good conjugation capability toward the biomolecules, and excellent analytical properties for determination of target molecules.