Fe—Ce—N—O,Fe—Y—N—S溶液的热力学研究

本文主要研究了在1570～1650℃范围内Fe-Ce-N-O、Fe-Y-N-S溶液的热力学性质,得到主要结果如下:(1)铈、钇增加氮的溶解度,氧轻微地增加氮的溶解度,硫轻微地减少氮的溶解度;(2)铈、钇、氧、硫与氮的相互作用系数与温度的关系。e_N~(Ce)=(-6230/T) 2.670,e_N~Y=(-6640/T) 2.986,e_N~O=(-3497/T) 1.650,e_N~S=264/T-0.128;(3)铈、钇脱氮产物为CeN、YN;(4)铈、钇脱氮常数与温度的关系:1gK_(CeN)-(-20960/T) 7.972,1gK_(YN)=(-20440/T) 7.863。     

Fe—ZSM—5分子筛中Fe的化学环境研究

本文应用ＥＳＲ、ＸＰＳ、ＤＲＳ、Ｍｏｓｓｂａｕｅｒ谱和首次运用ＴＰＲ技术结合ＸＰＳ、ＸＲＤ对Ｆｅ－ＺＳＭ－５中Ｆｅ的化学环境进行了研究。结果表明，碱性介质条件下合成的Ｆｅ－ＺＳＭ－５分子筛中，铁仅有一种价态Ｆｅ（Ⅲ），但却有多种存在形式。非骨架Ｆｅ（Ⅲ）包括分子筛孔道内及外表面上沉积的氧化铁；骨架Ｆｅ至少有两种状态，即骨架不饱和配位Ｆｅ（Ⅲ）和骨架畸变四配位的Ｆｅ（Ⅲ）．各种测试方法的结果表明Ｆｅ主要位于分子筛的骨架上，非骨架Ｆｅ（Ⅲ）很少．     

Fe—15Cr—4Al—Y合金中的Y—Fe相及其作用

在含０．２％－１．４％Ｙ的Ｆｅ－１５Ｃｒ－４Ａｌ－Ｙ合金中，１－１０μｍ的Ｙ－Ｆｅ相质点弥散分布，其硬度高于ａ相的２倍，组成可用Ｙ２（Ｆｅ７６Ｃｒ１２Ａｌ１１Ｓｉ）１７表示。Ｙ－Ｆｅ相强烈俘获ａ相中的碳原子，使合金在固溶处理状态下的Ｓｎｏｅｋ内耗峰消失，在７００℃下析出碳化物。Ｙ－Ｆｅ相南点通过阻止闰长大而抑制合金的高温脆化，通过俘获碳原子而延缓４７５℃脆性发展。此外，它们还有提高热强性和抗氧化性     

Thermal Treatments of Fe—Mn Alkoxide of Glycerol: Infrared absorption and emission spectroscopy

Synthetic Fe—Mn alkoxide of glycerol samples are submitted to controlled heating conditions and examined by IR absorption spectroscopy. On the other hand, the same sample is studied by infrared emission spectroscopy (IRES), upon heating in situ from 100 to 600°C. The spectral techniques employed in this contribution, especially IRES, show that as a result of the thermal treatments ferromagnetic oxides (manganese ferrite) are formed between 350 and 400°C. Some further spectral changes are seen at higher temperatures.This revised version was published online in November 2005 with corrections to the Cover Date.     

Fe—C—Sb—Ce,Fe—C—Sb—Y溶液中热力学性质的研究

用金属溶液与高熔点的金属间化合物平衡方法,研究了1300～1500℃含微量氧、硫的Fe-C-Sb-Ce,Fe-C-Sb-Y溶液的热力学性质。经X射线衍射确定平衡产物分别为化合物CeSb、YSb.研究得到反应式CeSb=[Ce]+[Sb]和YSb=[Y]+[Sb]的平衡常数与温度的关系;铈与锑、钇与锑的相互作用系数与温度的关系;CeSb_(s)和YSb_(s)的标准生成自由能与温度的关系。     

Electrochemical corrosion of thin ferromagnetic Fe—N films in neutral solution

A model experiment was conducted in order to determine an interplay between inherent strains and electrochemical corrosion rate in nitrogen-doped iron thin films. 150 and 300 nm thick films, used in the experiment, were obtained by means of DC magnetron sputtering. In order to study the influence of substrate on inherent strains in metal, these films were deposited onto flexible polymer and rigid glass substrates. It was found, that the rigidity of the substrate increased the corrosion rate of thin iron films in a neutral electrolytic solution. It was proven using X-ray diffraction, that the greater rigidity was, the stronger were the internal strains within the films. That effect was especially pronounced in thinner films, where the increase in the rate of dissolution was accompanied by a localization of corrosion. Characteristics of electrochemical processes were measured using a three-electrode cell. The comparison of the films free surface energy was performed by measuring water contact angle.     

Influence of Fe concentration on the properties of the electrodeposited Zn–Fe coatings

Electrodeposition of Zn–Fe alloys on a copper substrate from a sulfate bath with different Fe²⁺ concentration (0.05, 0.10 and 0.20 mol L^?1) at room temperature was investigated using cyclic voltammetry. The influence of the Fe²⁺ content in the plating bath on the surface morphology, structural and magnetic properties of the coatings were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Vibrating Sample Magnetometer (VSM). The results show that the morphology of Zn–Fe films changes with different Fe²⁺ concentration. The EDS analysis demonstrated that the Fe content of the coatings increased with increasing the Fe concentration in the bath. XRD measurements shows the presence of ?Zn (hcp), δ1ZnFe (hcp) and the ΓZnFe (bcc) phases with a (101) preferential orientation in all the electrodeposited films. The magnetic analysis of Zn–Fe films indicated that the saturation magnetization was largely enhanced in comparison to pure Zn, especially with 0.2 at. % Fe, while the coercivity decreased.     

Fe—Si—ZSM—12分子筛的表征

本文用红外光谱研究了Fe-Si-ZSM-12分子筛,观察到其结构单元的骨架振动谱带在545cm~(-1)、580cm~(-1)和630cm~(-1),而表示Si—O—Fe键的对称伸缩振动谱带在660cm~(-1)和780cm~(-1),且随铁含量增加向高波数位移。Fe-Si-ZSM-12分子筛的穆斯堡尔谱的结果表明,骨架铁的IS值很小,IS=0.086(-0.17)mm/s,且QS=0.0mm/s,这明显不同于非骨架铁IS=0.53mm/s。在Fe-Si-ZSM-12分子筛的ESR谱图上,观察到骨架铁的顺磁信号(g=4.3),样品焙烧后顺磁信号减弱,骨架铁向非骨架位迁移。IR、Mossbauer、ESR结果证明,Fe~(3+)进入了骨架。     

Nd—Fe—B—Si合金的研究

为了探索提高Nd-Fe-B磁性材料的居里温度T_C,我们采用了与文献不同的组成和制 条件,研究了Si对合金的物相、T_C等的影响,得出Nd-Fe-B-Si是一种有希望的非钴高居里温度合金体系. 试样系以钕铁、硅铁、硼铁和还原铁粉为原料,按 Nd_(15)Fe_(77-x)Si_xB_8(x=4、8、16、18 at％)配比,在石墨电阻炉内于Ar气保护下熔炼而成.T-σ曲线在日本MB-2型磁天平上测得;微区分析和x-射线衍射分别用JXA-840扫描电镜和日本理学2028x-射线衍射仪进行.     

Studies on Structure and Electrocatalytic Hydrogen Evolution of Nanocrystyalline Ni—Mo—Fe Alloy Electrodeposit Electrodes

Nanocrystalline Ni‐Mo‐Fe alloy deposits were obtained by electrode‐position. The structures of the alloy deposits were analyzed by X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). The XRD results of nanocrystalline Ni‐Mo‐Fe alloy deposit show that many diffraction lines disappear, and that there is only one diffraction peak at 44.0°. The XPS results of nanocrystalline Ni‐Mo‐Fe alloy deposits indicate that the nickel, molybdenum and iron of the deposits exist in metallic state, and that the binding energy of the alloyed elements increases to some extent. The nanocrystalline Ni‐Mo‐Fe alloy deposit electrode may offer better electrocatalytic activity than the polycrystalline nickel electrode and the nanocrystalline Ni‐Mo alloy electrode. The electrochemical impedance spectra from the nanocrystalline Ni‐Mo‐Fe alloy electrode indicate that hydrogen evolution in 30% (m/m) KOH at lower overpotential is in accordance with the Vohner‐Tafel mechanism, but with the Vohner‐Heyrovsky mechanism at higher overpotential.     

Thermal decomposition and reducibility of silica-supported precursors of Cu,Fe and Cu–Fe nanoparticles

Journal of Thermal Analysis and Calorimetry - Poly(butylene succinate) (PBS) nanocomposites filled with nanoprecipitated calcium carbonate (NPCC) were prepared via melt blending. The hybrid...     

用Fe（Ⅲ）—络天青S—CTMAB—β—CD测定谷物中的Fe（Ⅲ）

用正交法求得Ｆｅ（Ⅲ）－络天青Ｓ－ＣＴＭＡＢ－β－ＣＤ体系的最适宜条件。其结果与用原子吸收法和Ｆｅ（Ⅲ）－硫氰化物－Ｔｒｉｔｏｎ－Ｘ１００法所得的结果相当吻合。     

Fe—Sn—Fe三核金属有机化合物分配薄层色谱与紫外光谱的研究

王序昆等合成了一系列(Fe(CO)_2CP)_2Sn—Ar—R三核金属有机化合物。R:—H,—O-CH_3,P-CH_3,m-CH_3;—P-OCH_3;—m-Cl,—P-Cl;2,4,6-(CH_3)_3,2,3,4,5,6-(Cl)_5。X:—Sph,—SCN,—SCNMe,—NO_2,—NO_3,—N_3,—Cl,—Br,—I。我们用分配薄层色谱研究了它们的色谱行     

Fe—Sn—Ce溶液的热力学性质研究

本文研究了1550～1670℃温度范围内Fe-Sn-Ce溶液体系的热力学性质。在溶液中存在微量铈、氧、锡、硫条件下,未发现铈与锡的金属间化合物,而是铈与氧硫建立平衡。求得反应Ce_2O_2S=2[Ce]+2[O]+[S]的平衡常数及Ce_2O_2S的标准生成自由能。铈与锡的一阶、二阶相互作用系数与温度的关系式分别为:lgK=-29420/T+1.58;ΔG°=-563150+30.24T;e_(Sn)~(Ce)=95889/T+48.50T;γ_(Sn)~(Ce)=21132/T-10.44。     

Nd—Fe—B烧结磁体的磁化行为

研究了热退磁态和磁场退磁态Nd-Fe-B和Nd-Dy-Fe-B烧结磁体室温至150℃不同磁化场的磁化曲线、退磁曲线和磁滞回线。室温下磁场退磁态磁化曲线和内禀矫顽力_MH_C随磁化场H_M的变化曲线在磁化场接近样品最大内禀矫顽力绝对值时出现台阶,当温度升至100～150℃或样品在居里温发以上热退磁后,磁化曲线的形状由阶梯型变成陡峭型,而且_MH_C—H_M曲线的台阶移到低磁化场。膝点矫顽力H_K随H_M的快速升高出现在_MH_C随H_M的快速升高之后。表明Nd-Fe-B烧结磁体的磁硬化主要被畴壁钉扎所控制。     

Incoporation of Fe(Ⅲ) in framework of zeolite L

Zeolite L with Fe in lattice position is prepared from the gel with Fe/(Fe+Al) ratio up to 0.4 using ferric nitrate as Fe source. The incorporation of Fe(Ⅲ) in framework is characterized by XRD, IR, TG/DTA, BET and Mossbauer spectroscopy. Zeolite L is destabilized by Fe(Ⅲ) in framework and the reduction of Fe(Ⅲ) in framework of (Al,Fe )KL was first reported.     

铸造Pr—Fe—B永磁合金及其微观结构

采用铸造法制备稀土永磁体的关键在于找到合适的合金系以使铸造组织具有高矫顽力。最近,日本的Shimoda等人发现典型成分为Pr_(17)Fe_(76.5)B_5Cu_(1.5)的Pr-Fe-B合金经铸造/退火后,_iH_C,达7.4kOe.经热压/退火后磁体具有优异的永磁性能:B_r=12.5kGs,_iH_C=10.0kOe,(BH)_m=36.2MGOe,为系统认识该新型铸造永磁合金,本文对Pr-Fe-B永磁合金进行了铸造,退火实验研究和微观结构分析。