铁泥制备纳米四氧化三铁

以铁泥为原料，采用氧化-共沉淀相转移法制备纳米四氧化三铁,通过实验确定反应的最佳条件是pH=9，相转化反应温度为80℃，相转化时间为2h，R=n（Fe^3＋）／72（Fe^2＋）为1.75．利用IR、XRD、SEM进行表征，根据Scherrer公试计算产品粒径，平均粒径为62mm.     

正交实验法优选铁泥制备纳米四氧化三铁

以铁泥为原料,采用双氧水氧化法制备纳米四氧化三铁粉体.研究温度、溶液pH、双氧水用量及反应时间对产率的影响.得到最优实验条件:反应温度75℃;反应时间3 h;双氧水:0.5 mL;溶液pH=11.采用XRD、SEM等测试手段对产物进行表征,产物为Fe3O4,平均颗粒大小为100 nm.     

电镀污泥水热合成掺杂的四氧化三铁

以电镀污泥为掺杂源水热合成掺杂的Fe3O4,实现电镀污泥的资源化与自净化.选择尿素作为Fe3+Fe3+沉淀剂,通过分析电镀污泥掺杂量、反应时间及反应温度对水热合成Fe3O4的影响,确定最佳试验条件为:铁源与电镀污泥质量比4:1,反应时间4 h,反应温度160℃.研究结果同时表明,在掺杂Fe3O4中,铜的浸出毒性较大,镍次之,但锌、铁、铬的毒性浸出在pH值为3～10范围内低于美国固体废物毒性浸出(TCLP)方法的标准.因此,含铜量高的电镀污泥不适于用作掺杂源.应优先考虑含锌、铬污泥.水热合成的掺杂电镀污泥的Fe3O4,其粉体颜色呈黑色,磁性强,分散性好,粒度细小,分布较为均匀.     

化学沉淀法提取铬渣中四氧化三铁的研究

利用化学共沉淀法,在处理铬渣的同时,制备四氧化三铁。通过等离子体发射光谱仪检测,分析出四氧化三铁的纯度和产率,并讨论了铁盐浓度、沉淀剂浓度以及温度对产率和纯度的影响。     

还原氧化石墨烯/四氧化三铁复合气凝胶的制备与染料吸附性能

为改进四氧化三铁（Fe₃O₄）复合材料吸附工业染料废水的性能,先制备了表面油酸修饰的Fe₃O₄,再以氧化石墨烯（GO）及表面油酸修饰的Fe₃O₄作为前驱物,通过水热法制备了还原氧化石墨烯/四氧化三铁（rGO/Fe₃O₄）复合水凝胶,最后冻干得到rGO /Fe₃O₄复合气凝胶。采用X射线衍射仪、扫描电子显微镜表征产物的微观形态和结构,并通过紫外-可见分光光度计对复合气凝胶对于亚甲基蓝染料（MB）的吸附性能进行研究。结果表明,rGO /Fe₃O₄复合气凝胶在微观上复合均匀,与单独的石墨烯和Fe₃O₄纳米粒子相比,rGO/Fe₃O₄复合气凝胶对MB染料的吸附性能更优,吸附能力达到108 mg·g^-1,而且rGO /Fe₃O₄复合气凝胶可以方便地从废水中移出进行重复使用。研究其吸附动力学和吸附等温发现,该复合气凝胶的吸附行为符合拟二级动力学方程和Langmuir吸附模型。     

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.     

DBSA含量对纳米Fe3O4/导电聚苯胺结构和 电磁性能的影响

以十二烷基苯磺酸（DBSA）为乳化剂和掺杂剂,过硫酸铵（APS）为氧化剂,采用乳液聚合的方法合成了导电聚苯胺包覆磁性四氧化三铁的核-壳纳米复合材料。通过TEM、FTIR、XRD、介电常数和磁导率的测量研究了反应中DBSA的含量对合成纳米颗粒的微观结构和电磁性能的影响。结果表明：当DBSA和苯胺的摩尔比为1.0时,得到的Fe3O4/PANI/DBSA微粒的粒径在120 nm左右,颗粒的分散状态较好;FTIR和XRD的表征说明,DBSA的加入量在很大程度上影响掺杂态聚苯胺的导电性和结晶性;介电常数和磁导率的测     

介孔氧化硅材料的合成及应用研究

采用十六烷基三甲基溴化铵（CTAB）为模板剂，通过加入不同量的1，3，5－三甲基苯（TMB）作为增大孔径的辅助剂合成出了不同孔径大小的氧化硅粉末，XRD、N2吸附曲线等测试手段表明所合成的材料为具有MCM－41结构特征的介孔材料；以该种材料制备了超微孔领域的多孔陶瓷，同时探讨了辅助剂对材料介孔结构和陶瓷气孔率的影响。结果表明，当辅助剂摩尔比小于x=0.4时，随着辅助剂加入量的增加，介孔材料的孔径、比表面积、结晶有序度等相应增加，但当加入量超过此范围时，结晶有序度反而下降，所获得的超微孔陶瓷其最大显气孔率可达56％。     

纳米晶304不锈钢高温氧化膜中氧元素的XPS研究

利用X-射线光电子谱(XPS)研究普通304不锈钢(CP-SS304)和用深度轧制技术制备块体的纳米晶304不锈钢(BN-SS304)在900℃空气中氧化24h形成氧化膜中氧元素的结合能和原子百分比.BN-SS304和CP-SS304氧化膜表面氧元素以分子态(O0)和离子态(O2-)存在;BN-SS304和CP-SS304氧化膜中O0和O2-的结合能相同;Ar+溅射400s时不存在分子氧,而CP-SS304氧化膜溅射800s时不存在分子氧;从溅射开始至溅射800s,BN-SS304氧化膜中O2-与(O2-+O0)原子数的比值大于CP-SS304,最大差距为8.92％.结果表明,BN-SS304氧化膜表面吸附O2深度较低;BN-SS304氧化膜致密性更好.     

Synthesis and Characterization of Biomimetic Fe_3O_4/Coke Magnetic Nanoparticles Composite Material

A composite material(Fe_3O_4/Coke)using coke supported Fe_3O_4 magnetic nanoparticles was successfully prepared via an in-situ chemicaloxidation precipitation method and characterized by SEM,XRD,Raman,and FTIR.The results showed that the Fe_3O_4 nanoparticles existed steadily on the surface of coke,with better dispersing and smaller particle size.The catalytic ability of Fe_3O_4/Coke were investigatied by degrading p-nitrophenol(P-NP).The results showed that the apparent rate constant for the P-NP at 1.0 g·L~(-1) catalyst,30 mmol·L~(-1) H_2O_2,pH=3.0,30 ℃ and the best ratio of Coke/Fe_3O_4 0.6,was evaluated to be 0.027 min~(-1),the removalrate of CODCr was 75.47%,and the dissolubility of Fe was 2.42 mg·L~(-1).Compared with pure Fe_3O_4,the catalytic ability of Fe_3O_4/Coke in the presence of H_2O_2 was greatly enhanced.And Fe_3O_4/Coke was a green and environmentalcatalyst with high catalytic activity,showing a good chemicalstability and reusability.     

丁醇还原法制备Fe_3O_4的研究

研究了丁醇还原法制备Fe_3O_4的设备和工艺条件,分析了丁醇还原机理,考察了脱水、还原温度对Fe_3O_4微观结构的影响。实验表明,330℃脱水和还原时,所得Fe_3O_4的比表面积最大,矫顽力最高,活性最强。     

单分子前躯体法合成Fe3O4纳米颗粒

在室温下,用三氯化铁(FeCl3·6H2O)、醋酸钠(CH2COONa)和乙酰丙酮通过简单的沉淀反应得到乙酰丙酮铁(Fe-(ACAC)3)固体粉末,并以此作为前驱体,在20%水合肼中80-160℃水热处理12 h制得了纯Fe3O4(磁铁矿)纳米晶,利用XRD、TEM、VSM、FTIR和拉曼光谱等多种现代分析测试手段对产品的结构、组成、形貌、大小和磁性等进行了表征,并探讨了产物可能的合成机理.     

Facile Fabrication of Fe_2O_3/Nitrogen Deficient g-C_3N_(4-x) Composite Catalysts with Enhanced Photocatalytic Performances

The modification of graphitic carbon nitride can significantly improve the photocatalytic performance of graphitic carbon nitride(g-C_3N_4). Fe_2O_3/nitrogen-deficient g-C_3N_(4-x) composite catalysts were prepared with dicyandiamide as the precursor and Fe~(3+) doped in this study. The composite catalysts were characterized by XRD, SEM, FT-IR, XPS and photocurrent measurements. Close interaction occurred between Fe_2O_3 and nitrogen deficient g-C_3N_(4-x), more photogenerated electrons were created and effectively separated from the holes, resulting in a decrease of photocarrier recombination, and thus enhancing the photocurrent. Photocatalytic performance experiments showed that Fe_2O_3/nitrogen deficient g-C_3N_(4-x) could utilize lowenergy visible light more efficiently than pure g-C_3N_4, and the removal rate was 92% in 60 minutes.     

磁性纳米Fe3O4粒子的制备与应用

为了对磁性纳米Fe3O4颗粒的制备和应用进行总结和回顾,综述了磁性纳米Fe3O4颗粒的机械研磨法、沉淀法、微乳液法、溶剂热法、溶胶-凝胶法、热分解有机物法等几种主要制备方法,分析了各制备方法的特点;介绍了磁性纳米Fe3O4颗粒在磁流体、磁记录材料、生物医学以及催化剂载体等领域的应用,并对磁性纳米Fe3O4颗粒未来的研究重点和应用前景进行了展望：如何更经济更环保地制备粒径可控且分布均匀的磁性纳米Fe3O4微粒是今后研究的热点与重点;纳米Fe3O4颗粒同时具备磁性颗粒和纳米颗粒的双重优势的应用性研究也极为重要.     

Fe3O4超细粒子催化剂的制备

使用TG DTA、XRD、Mossbauer谱等方法考查了制备条件对草酸铁热分解过程的影响。结果表明 ,Fe2 (C2 O4) 3·xH2 O在氮气流中 473K下失去结晶水的同时 ,将部分转变成草酸亚铁 ,生成的草酸亚铁只有在 573K以上才开始分解 ,草酸铁则在 533K时就开始分解 ,且分解产物为超细Fe3O4粒子。     

Synthesis of size-controllable Fe_3O_4 magnetic submicroparticles and its biocompatible evaluation in vitro

Large scaled uniform and size-controllable magnetic submicroparticles(MSPs) were synthesized via solvothermal method with ferric chloride as iron source and sodium acetate as trapping agent. The influence of Fe~(3+) and Na Ac contents on the size distribution of MSPs was investigated. The structural and morphological properties of the synthesized particles were studied by scanning electron microscopy(SEM), X-ray power diffraction(XRD) and vibrating sample magnetometer(VSM). The well-dispersed MSPs with size of 100-1000 nm were obtained by simply adjusting the contents of Fe~(3+) and NaA c. In addition, the hemolysis and cytotoxicity of Fe_3O_4 MSPs, and their ability to case arrest in cell life-cycles were studied. The results indicate that larger size could lead to lower hemolysis. From MTT(3-(4,5-dimethylthuazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, the interactions between MSPs and adhesive mouse fibroblast cell line(L929) were probed. Larger size of Fe_3O_4 MSPs demonstrates lower cell viability following an exposure to the cells.     

Fe_3O_4@PAM@NTA-Ni~(2+) Magnetic Composite Nanoparticles for Highly Specific Separation of His-tagged Proteins

A facile approach has been developed to synthesize Fe_3O_4@PAM(polyacrylamide) nanoparticles(NPs) with carboxyl groups on the surfaces by copolymerization with acrylamide and acrylic acid in Fe_3O_4 NPs aqueous suspension. Nitrilotriacetic acid(NTA) was conjugated to the magnetic NPs via well-known carboniimide chemistry using EDC and NHS. The Ni~(2+) ions loaded on the surface of NPs provide abundant docking sites for immobilization of His-tagged green fluorescent proteins(His-tagged GFP). The high magnetic property of Fe_3O_4@PAM@NTA-Ni~(2+) allows an easy separation of the NPs from solution under an external magnetic field, with high His-tagged protein binding capacity(42 μg protein/mg of NPs). The NPs can be recycled for at least four times without significant loss of binding capacity to proteins. These materials show great potential to separate His-tagged protein with low-cost purification at industrial scale.     

水热法制备SiO_2@Mn_2O_3球形纳米粒子

以二氧化硅微球为模板,乙酸锰和尿素为反应物,在水热条件下合成了SiO_2@MnCO_3中间产物,经煅烧后获得SiO_2@Mn_2O_3。主要考察了尿素浓度、二氧化硅模板用量对中间产物形貌和结构的影响。利用热重分析仪(DSC/TG)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和氮气吸附脱附对产物进行了表征。实验结果表明:尿素浓度和二氧化硅模板的用量对产物形貌和结构有明显影响;产物煅烧前后形貌、结构变化不大,但是煅烧后产物的BET比表面积显著增大,孔径明显减小。