分光光度法研究高铁酸钾在碱性介质中的化学反应动力学

高铁酸盐是一种新型的绿色电源材料,在研究其实际应用时有必要对其化学性质进行研究,了解高铁酸盐作为电源材料的性能。本文用分光光度法研究K_2FeO_4在不同的碱性介质,不同碱浓度的水解反应。确定K_2FeO_4水解反应级数,计算反应半衰期,研究添加离子对K_2FeO_4水解反应的影响。     

绿色氧化剂K2FeO4对瓜尔胶的降解实验研究

瓜尔胶在油田压裂液中作为稠化剂被广泛使用,作业后的压裂返排液中瓜尔胶难以自然降解,对环境造成严重危害;探索绿色高效处理油田压裂返排液的方法成为研究的热点和难点.本实验以K2FeO4为绿色高效氧化剂,对模拟压裂返排液(质量浓度为0.3‰瓜尔胶溶液)进行了降解实验研究,结果表明,当K2FeO4用量为0.5 g/L,反应温度30 ℃,反应pH值为12.0时,溶液降黏率最大可达89.27%,COD去除率为36.27%,且氧化剂反应为三价铁离子,绿色无污染.     

FeO(OH)胶体加载微生物絮凝剂及其脱色特性

在未经人工培养的啤酒厂活性污泥中,以水合氧化铁胶粒吸附微生物絮凝剂并加载于其表面,应用于混凝脱色,建立了一种聚集微生物絮凝剂和增效的实用方法。研究了pH值、调pH值的时机、上清液与水合氧化铁溶胶投量比以及Ca^2 的存在对脱色效果的影响,结果表明：pH值为10;上清液与水合氧化铁溶胶投量比为1．5;pH值的调节在FeO(OH)溶胶加入之前,直接黄染料(DY4)的最高脱色率达98．7％。Ca^2 对本系统无明显作用。     

Synthesis,Electrical Conductivity and Seebeck Coefficient of La_(0.9)A_(0.1)FeO_3(A=Mg,Ca,Sr,Ba)

Lanthanum ferrites ceramics La0.9A0.1FeO3(A=Mg,Ca,Sr,Ba) have been prepared by solid state reaction.X-ray power diffraction analysis reveals that all samples are of pure perovskite structure with orthorhombic phase.Electrical conductivity and Seebeck coefficient have been measured in vacuum within the temperature range between room temperature and 800℃.The electrical conductivity shows semiconducting behavior.Temperature dependence of electrical conductivity indicates that adiabatic small-polaron hopping me...     

钛白废酸在过磷酸钙生产中的应用

硫酸法钛白粉生产会产生w（H2SO4）21％、w（FeO）5．6％的废酸,如直接用于过磷酸钙生产,因FeO存在会造成硫酸输送管道堵塞,过磷酸钙结块和有效磷退化。介绍除去废酸中FeO的工艺技术,可使酸中的Ⅲ（FeO）降至0．27％。几年来回收废酸（折纯100％）4．63万t,合计创效益3240万元。     

直接和间接电合成制备出的高铁酸钾的物理和电化学性能

K2FeO4powders were synthesized by the ex-situ and in-situ electrochemical methods, respectively, and characterized by infrared spectrum (IR), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and BET. Their electrochemical performances were investigated by means of galvanostatic discharge and electrochemical impedance spectroscopy (EIS). The results of physical characterization showed that the two samples have similar structural features, but their surface morphologies and oriented growth of the crystals are different, which results in smaller specific surface area and lower solubility of the ex-situ electrosynthesized K2FeO4 sample. The results of discharge experiments indicated that the ex-situ electrosythesized K2FeO4 electrode has much larger discharge capacity and lower electrode polarization than the in-situ electrosynthesized K2FeO4 electrode. It was found from the results of EIS that lower electrochemical polarization might be responsible for the improvement on the discharge performance of the ex-situ electrosynthesized K2FeO4 electrode.     

纳米晶La0.7Pb0.3FeO3的制备及其对CO敏感特性的研究

利用溶胶-凝胶法制备了纳米晶La0.7Pb0.3FeO3气敏材料,并对其相组成、电导及其对CO气敏性能进行了研究.XRD结果表明：掺铅固溶体La0.7Pb0.3FeO3仍为正交晶系钙钛矿结构,粒径约为17nm,低于纯相LaFeO3的粒径31nm。电导测鼍显示：该材料足P型半导体导电行为，电导大于同温度下纯相LaFeO3的电导，且电导突变温度有所降低。气敏性能研究表明：Pb掺杂对其CO气敏性能有了明显改善。     

纳米晶La_(0.7)Pb_(0.3)FeO_3的制备 及其对CO敏感特性的研究

利用溶胶-凝胶法制备了纳米晶La0.7Pb0.3FeO3气敏材料,并对其相组成、电导及其对CO气敏性能进行了研究。XRD结果表明:掺铅固溶体La0.7Pb0.3FeO3仍为正交晶系钙钛矿结构,粒径约为17nm,低于纯相LaFeO3的粒径31nm。电导测量显示:该材料呈p型半导体导电行为,电导大于同温度下纯相LaFeO3的电导,且电导突变温度有所降低。气敏性能研究表明:Pb掺杂对其CO气敏性能有了明显改善。     

Mössbauer spectroscopy,XRPD, and SEM study of iron-containing Na2O-B2O3-SiO2 glasses

Glasses in the Na₂O-B₂O₃-SiO₂-Fe₂O₃ system are suitable for producing magnetic porous glasses—host matrices for multiferroic composite materials for spintronics applications. Successful synthesis of such materials is dependent on the knowledge of crystallization and immiscibility areas in this system. Here, we report new findings for such glasses with a constant SiO₂ concentration of 70 mol %, containing 7-12 mol % Fe₂O₃, whose compositions lie in the low (2 mol % Na₂O) and higher (8-12 mol % Na₂O) alkali regions, heat-treated at 550°C. Glasses were studied using analytical chemistry methods and investigated by means of Mössbauer spectroscopy, XRPD and SEM. We outlined the immiscibility area boundary in the chosen silica cross-section for 550°C, indicating the region of interconnected morphology and the crystallization fields of magnetite and FeSiO₃, and correlated them with data on the valence and coordination state of iron in glasses. We find that both Fe³⁺ and Fe²⁺ ions in the low-alkali region are octahedrally coordinated, in higher alkali area Fe³⁺ and Fe²⁺ are tetrahedrally and octahedrally coordinated, respectively. A significant amount of Fe²⁺ in the low-alkali region can be the cause of the FeSiO₃ formation. The usual crystalline phase in non-X-Ray amorphous glasses is magnetite, precipitating at the annealing stage.     

氨基功能化磁性FeO(OH)纳米棒的制备研究

在获得表面修饰氨基官能团的磁纳米棒,为进一步偶联生物分子制备出磁生物双靶向纳米药物奠定基础.以部分氧化法制备了磁性FeO(OH)纳米棒,并在保持原有形貌的基础上对其进行硅胶包覆和氨基功能化,从而获得功能化磁纳米药物载体.磁纳米棒的形貌特征、晶体结构、磁性质和表面基团分别通过TEM(SAED)、XRD、VSM和FTIR进...