纳米Fe3O4对沼液MFC产电特性与有机物降解影响

为了提高微生物燃料电池（MFC）对沼液中有机质的降解和产电效率，将纳米Fe3O4与MFC结合，对比研究了纳米Fe3O4以Fe3O4@生物炭和Fe3O4@碳毡两种不同介入方式对MFC性能的影响。结果表明，两种方式均可成功启动MFC，且产电效率远高于无纳米Fe3O4介入的空白实验，最高电压分别为699和707 mV，最高电压均持续时间长达10 d。Fe3O4@碳毡与Fe3O4@生物炭介入下MFC最大功率密度分别为700和578 mW/m2，相较于未使用纳米Fe3O4的MFC提高了43%和31%。将Fe3O4@碳毡作为阳极电极得到的化学需氧量（COD）降解率最高，为51.76%；直接投加Fe3O4@生物炭对NH4+-N的降解影响最大，投加Fe3O4@生物炭后NH4+-N含量由（6800.14±57.86） mg/L降至（689.14±37.29） mg/L，NH4+-N降解率达到89.87%。纳米Fe3O4参与的MFC微生物群落结构合理，两种介入方式均刺激了主要水解细菌梭菌纲（Clostridia）的生长富集。随着纳米Fe3O4的位置变化，Clostridia的相对丰度在以Fe3O4@生物炭和Fe3O4@碳毡介入的MFC中分别达到61.11%、50.98%。二者的电活化细菌中β-变形菌纲（Betaproteobacteria）含量最高，并且在反应后碳毡上发现了反硝化细菌芽孢八叠球菌属（Sporosarcina）。     

Fe_3O_4@ZIF-8的制备及其在磁固相微萃取中的应用

制备了Fe3O4@ZIF-8磁纳米复合材料,以其作为吸附剂建立快速高效的磁固相微萃取方法。首先用水热法合成Fe3O4纳米球,然后进行羧基功能化,最后包覆ZIF-8外壳制备了Fe3O4@ZIF-8微球。以萘、蒽、咔唑、芴、联苯等多环芳烃为分析物建立HPLC-UV方法。以峰面积为响应信号,作为萃取条件优化实验的测量指标,考察微球用量、萃取时间、解吸溶剂种类、解吸溶剂用量、解吸时间等因素对萃取效果的影响,建立了快速高效的磁固相微萃取方法。用Fe3O4@ZIF-8磁纳米复合材料对环境水样中的痕量多环芳烃进行磁固相微萃取,实现了对环境水样中痕量多环芳烃的快速灵敏测定。     

Fe~(3+)@酵母菌非均相UV-Fenton降解染料废水

以球形酵母菌为生物载体,饱和吸附Fe3+后,获得了Fe3+@酵母菌核壳微球。SEM,EDS及FT-IR对微球的结构进行了表征。实验研究了Fe3+@酵母菌非均相UV-Fenton降解碱性嫩黄O染料废水,考察了H2O2浓度、Fe3+@酵母菌催化剂的投加质量浓度、pH值、碱性嫩黄O染料的初始质量浓度等对反应的影响。结果表明,微球的直径在3.1—3.3μm,具有较好的球形形貌和壳壁强度。核壳结构的形成主要源自于生物吸附作用。当H2O2浓度为3.5 mol/L,pH值为3—4,催化剂质量浓度为5.5 g/L时,Fe3+@酵母菌非均相UV-Fenton降解碱性嫩黄O染料废水表现出了较好的去除效率。     

Core-shell Fe3O4@SiO2 nanoparticles synthesized with well-dispersed hydrophilic Fe3O4 seeds

Silica coated magnetite (Fe3O4@SiO2) core-shell nanoparticles (NPs) with controlled silica shell thicknesses were prepared by a modified St?ber method using 20 nm hydrophilic Fe3O4 NPs as seeds. The core-shell NPs were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), selected area electron diffraction (SAED), and UV-Vis adsorption spectra (UV-Vis). The results imply that NPs consist of a crystalline magnetite core and an amorphous silica shell. The silica shell thickness can be controlled from 12.5 nm to 45 nm by varying the experimental parameters. The reaction time, the ratio of TEOS/Fe3O4, and the concentration of hydrophilic Fe3O4 seeds were found to be very influential in the control of silica shell thickness. These well-dispersed core-shell Fe3O4@SiO2 NPs show superparamagnetic properties at room temperature.     

聚丙烯酸修饰的Fe3O4@C核壳型微球的制备及其在锂离子电池 负极中的电化学性能

锂离子电池作为最有前途的储能技术之一,因具有循环寿命长、能量密度大、自放电率低、热稳定性能好、记忆效应不明显等优势,已成为新型能源领域的研究热点。本工作以聚丙烯酸(PAA)修饰的粒径约250 nm的Fe3O4微球为核,葡萄糖为碳源,通过水热法制备了Fe3O4@C核壳型微球,研究其作为锂离子电池负极材料的电化学特性。通过X射线衍射(XRD)、扫描电镜(SEM)、热重(TGA–DTA)和傅里叶红外光谱(FT-IR)等手段对其表征,并通过循环伏安特性曲线、循环性能曲线、倍率性能曲线,充放电平台曲线和阻抗及其拟合曲线等研究其电化学性能。结果表明,制备的聚丙烯酸(PAA)修饰的Fe3O4@C核壳型微球球状完整,粒径均一,平均尺寸约310 nm,碳层表面光滑,包覆均匀,平均厚度约30 nm。Fe3O4@C的核壳结构有效缓解了恒流充放电过程中的体积膨胀,避免了晶体结构的快速坍塌。PAA中大量的羧基基团对Fe3O4起到表面改性的作用,有效避免了颗粒团聚,保证了良好的分散性。碳的有效包覆可改善Fe3O4材料作为锂离子电池负极材料的离子和电子电导,增加其比容量、库伦效率和循环稳定性。Fe3O4@C核壳型微球在100 mA/g电流密度下,恒流充放电循环370圈后,仍能保持655 mAh/g放电比容量,约为首次放电的50%,具有良好的容量保持率。     

Synthesis of micro-sized SnO2@carbon hollow spheres with enhanced lithium storage properties

Uniform and stable micro-sized SnO(2) hollow spheres are prepared by templating against polystyrene microspheres. After being coated with a thin layer of amorphous carbon, the as-obtained SnO(2)@carbon hollow microspheres are shown to exhibit improved lithium storage properties, delivering a reversible capacity of 570 mA h g(-1) after 50 cycles at a high current density of 400 mA g(-1).     

磁性二氧化钛-磷钨酸复合催化剂的制备及光催化性能研究

采用层层自组装法成功制备了兼具磁性和光催化活性的双功能Fe_3O_4@SiO_2/(TiO_2/PW_(12))_(10)复合微球,利用扫描电镜、红外光谱和X-射线能谱仪对所得微球进行了结构和形貌的表征。以甲基橙为模型污染物,研究了紫外光下Fe_3O_4@SiO_2/(TiO_2/PW_(12))_(10)的光催化性质,系统考察了甲基橙溶液的初始浓度、溶液pH和无机氧化剂碘酸钾对复合膜催化效率的影响。动力学研究表明,在不同浓度甲基橙溶液中,染料的光催化降解遵循表观一级反应动力学。磁性Fe_3O_4纳米粒子的使用实现了反应后催化剂方便、快速和高效地分离回收。     

Magnetic spherical cores partly coated with periodic mesoporous organosilica single crystals

Core-shell structured materials are of special significance in various applications. Until now, most reported core-shell structures have polycrystalline or amorphous coatings as their shell layers, with popular morphologies of microspheres or quasi-spheres. However, the single crystals, either mesoscale or atomic ones, are still rarely reported as shell layers. If single crystals can be coated on core materials, it would result in a range of new type core-shell structures with various morphologies, and probably more potential applications. In this work, we demonstrate that periodic mesoporous organosilica (PMO) single crystals can partly grow on magnetic microspheres to form incomplete Fe(3)O(4)@nSiO(2)@PMO core-shell materials in aqueous solution, which indeed is the first illustration that mesoporous single-crystal materials can be used as shell layers for preparation of core-shell materials. The achieved materials have advantages of high specific surface areas, good magnetic responses, embedded functional groups and cubic mesopore channels, which might provide them with various application conveniences. We suppose the partial growth is largely decided by the competition between growing tendency of single crystals and the resistances to this tendency. In principle, other single crystals, including a range of atomic single crystals, such as zeolites, are able to be developed into such core-shell structures.     

近单分散介孔SiO2/Fe3O4/SiO2微球的制备及漆酶固定化

以自制近单分散、平均粒径约为250 nm的SiO2亚微球为核心,采用液相沉积法得到β-FeOOH/SiO2微球,再通过溶胶-凝胶法以β-FeOOH/SiO2微球为内核,十六烷基三甲基溴化铵(CTAB)为模板剂,正硅酸乙酯(TEOS)为硅源,经水解缩聚反应,焙烧后得到近单分散介孔SiO2/Fe3O4/SiO2微球,以复合微球为载体,对漆酶进行固定。结果表明,近单分散介孔SiO2/Fe3O4/SiO2复合微球的介孔层厚约40 nm,具有较大的饱和磁化强度(14.715 emu/g),较小的剩余矫顽力(约为109Oe),其比表面积为391.067 m2/g,孔容为0.53 cm3/g,孔径分别在5.43 nm和20～80 nm,呈现双孔径分布。复合微球吸附漆酶后,介孔材料的比表面积与孔容分别减小为103 m2/g和0.37 cm3/g,复合微球对漆酶的吸附量为202.6 mg/g。     

A self-assembled polydopamine film on the surface of magnetic nanoparticles for specific capture of protein

In this study, we report a facile method for the preparation of core-shell magnetic molecularly imprinted polymers (MIPs) for protein recognition. Uniform carboxyl group functionalized Fe(3)O(4) nanoparticles (NPs) were synthesized using a solvothermal method. Magnetic MIPs were synthesized by self-polymerization of dopamine in the presence of template protein on the surface of the Fe(3)O(4) NPs. A thin layer of polydopamine can be coated on Fe(3)O(4) NPs via dopamine self-polymerization and the imprinted polydopamine shells can be controlled by the mass ratio of Fe(3)O(4) NPs and dopamine. More importantly, there is a critical value of polydopamine shell thickness for the maximum rebinding capacity. The as-prepared lysozyme-imprinted Fe(3)O(4)@polydopamine NPs show high binding capacity and acceptable specific recognition behavior towards template proteins. This method provides the possibility for the separation and enrichment of abundant proteins in proteomic analysis.     

Fe_3O_4/P(ST-AA)核—壳复合微球的制备和表征

本文以磁性氧化铁胶体粒子为种子,运用分散聚合法,制备出具有磁响应性Fe_3O_4/P(SI-AA)核—壳复合微球。考察了复合微球的形态及结构,测定了复合徽球的粒径和磁响应性,研究了分散介质,引发剂,聚合单体和种子粒子等因素对复合徽球形成的影响。适当调整有关反应条件,采用分散聚合法,可以使复合微球粒径达到23.0μm,磁性氧化铁含量达到9.0mg/s。     

Fe_3O_4/P(St-CBA)核壳磁性复合微球的制备及性质

运用分散聚合法制备出Fe3O4 /P(St -CBA)核壳磁性复合微球。该微球粒径为 0 .0 75～0 .70 0 μm、w(Fe3O4 ) =0 .0 5 %～ 0 .90 % ,呈规整球型 ,表面光滑 ,在 0 .0 5T磁场中的磁响应性为3.0cm/min。制备微球的最佳条件为 :w(磁流体 ) =0 .5 %～ 3 .0 %、w(马来酸酐 ) =0 .0 %～2 .0 %、w(无水乙醇 ) =30 .0 %～ 70 .0 %。     

Fe2O3中空微球的制备与表征

以自制碳球为模板,FeCl3为原料,经水解、高温煅烧,制备出粒径约为250 nm的Fe2O3中空微球。用X-射线衍射（XRD）、透射电镜（TEM）等现代测试手段对Fe2O3中空微球样品的结构、形貌进行了表征;并考察了煅烧时间的变化对所制备的Fe2O3中空微球的晶型及形貌的影响。     

分散聚合法合成含有环氧基的无孔超顺磁性微球及其表征

Non-porous superparamagnetic polymer microspheres with epoxy groups were prepared by dispersion polymerization of glycidyl methacrylate (GMA) in the presence of magnetic iron oxide (Fe3O4) nanoparticles coated with oleic acid. The polymerization was carried out in the ethanol/water medium using polyvinylpyrrolidone (PVP) and 2,2'-azobisisobutyronitrile (AIBN) as stabilizer and initiator, respectively. The magnetic microspheres obtained were characterized with scanning electron microscopy (SEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy (FTIR). The results showed that the magnetic microspheres had an average size of 1μm with superparamagnetic characteristics. The saturation magnetization was found to be 4.5emu·g-1. There was abundance of epoxy groups with density of 0.028 mmol·g-1 in microspheres. The magnetic PGMA microspheres have extensive potential uses in magnetic bioseparation and biotechnology.     

纳米光催化剂TiO_2/Fe_3O_4的制备及表征

采用两步法制备磁性负载纳米光催化剂TiO2/Fe3O4。首先用液相共沉淀法制备磁性纳米Fe3O4颗粒;然后用溶胶-凝胶法,以钛酸四正丁酯为先驱体,通过水解缩聚在Fe3O4纳米颗粒表面包覆TiO2层,得到易于磁分离回收的复合纳米光催化剂TiO2/Fe3O4,粒径大约为30 nm。利用TEM、XRD、FT-IR、VSM对Fe3O4和TiO2/Fe3O4的结构和性能进行了表征,结果表明,制备的Fe3O4为面心立方晶体(FCC)结构,具有超顺磁性;TiO2为锐钛矿相,包覆在Fe3O4的表面,形成了核-壳式结构的TiO2/Fe3O4复合光催化剂。     

Cu(Ⅱ)螯合壳聚糖磁性微球的制备、表征及性能研究

以(NH4)2Fe(SO4)2.6H2O、NH4Fe(SO4)2.12H2O和壳聚糖为原料,经羟丙基化、Cu(Ⅱ)螯合,采用一步包埋法制备了一种Cu(Ⅱ)螯合壳聚糖磁性微球。通过正交实验法确定了磁性微球的最佳制备条件,即搅拌速度1 200 r/min,壳聚糖用量3.0 g,环氧氯丙烷用量1.0 mL,CuCl2.2H2O为0.010 mol。并用IR、TG、XRD和SEM对其结构及形貌进行了表征,结果表明,Fe3O4磁性粒子已包埋了一层Cu(Ⅱ)螯合壳聚糖,呈较规则的球形,平均粒径为240 nm,且具有顺磁性。     

模板沉积法制备大孔高比表面积Fe3O4/P(GMA-co-EGDMA)磁性复合微球

介绍了一种以大孔高比表面积甲基丙烯酸缩水甘油酯（GMA）与二甲基丙烯酸乙二醇酯（EGDMA）共聚交联微球［P(GMA-co-EGDMA)］为模板制备磁性复合微球的简单方法。制备过程包括Fe³⁺和Fe²⁺的浸入、OH^-作用下孔内铁离子的共沉淀两步。在此过程中考察了浸泡温度、浸泡时间、共沉淀温度以及沉积次数对微球磁含量的影响,确定最佳制备工艺为50℃浸泡4 h,70℃反应1 h,如此反复4次磁含量可以达到45.24%。并通过SEM、VSM、XRD、TGA及压汞仪、激光粒度仪等手段对Fe₃O₄/P(GMA-co-EGDMA)的形貌、比饱和磁化强度、磁含量及孔性能进行了表征,微球的粒径范围处于100～200 μm之间,平均粒径为162 μm,比饱和磁化强度为10.92 emu·g^-1,平均孔径及比表面积分别为60 nm和116 m2·g^-1。     

Application of Magnetic ordered mesoporous carbon Nanocomposite for the Removal of Ponceau 4R Using Factorial Experimental Design

Silicon - Nanocomposites of ordered mesoporous carbon with silica coated magnetite nanoparticles (Fe3O4@SiO2-CMK-8, MNCs) were synthesized by carbonizing sucrose inside the pores of the Kit-6...     

中空多孔磁性Fe3O4/纤维素/海泡石微球异相Fenton催化降解亚甲基蓝

为开发一种高效可循环利用的磁性生物质基催化剂，以微晶纤维素和纳米Fe3O4为原料，采用包埋法制得Fe3O4/纤维素（Fe3O4/MCC）溶液，将海泡石（SEP）掺入至Fe3O4/MCC中，制得磁性纤维素/海泡石复合微球（Fe3O4/MCC/SEP）。通过SEM、FTIR、VSM等对磁性微球的形貌、化学结构及磁性能进行了表征，探讨了微球作为芬顿催化剂对亚甲基蓝（MB）染料的降解效果及机理。结果表明，Fe3O4/MCC/SEP微球呈现出优异的中空多孔结构和超顺磁性。当MB浓度为10 mg/L、pH为3、Fe3O4/MCC/SEP的投入量为0.02 g，H2O2用量为5 mL时，反应240 min对MB的Fenton催化降解率高达99%。此外，经过5次循环利用后，对MB的降解率仍达83%。     

磁性多孔Fe(OH)3微球制备及其在含磷废水处理中的应用

利用诱导成球法制备磁性Fe3O4粒子为核的Fe(OH)3多孔微球,以X射线衍射(XRD)和扫描电镜(SEM)等对其进行结构表征,采用静态吸附法对磁性多孔微球去除水中H2PO4-的性能进行了实验研究,考察了吸附剂用量、H2PO4-初始浓度、溶液pH值等因素对吸附的影响,分析了其吸附等温线及对H2PO4-的吸附动力学. 结果表明,Langmuir方程能较好地描述吸附平衡,其吸附动力学符合Lagergren二级方程. 磁性多孔微球对H2PO4-有很强的去除能力,在吸附剂用量0.8 g/L,pH 2.5~9,吸附时间150 min的条件下,磁性多孔微球对H2PO4-的去除率可达98%以上.