Study on Rare Earth Electrolyte of Ce_(0.9)RE_(0.1)O_(2-δ) (RE=Pr, Nd, Sm, Gd, Dy)

Thesolidelectrolyteisakeycomponentofsolidoxidefuelcell (SOFC) .Dopedceriaisoneofpromis inghigh conductingsolidelectrolyteinSOFC[1,2 ] .Butitiswell knownthatitisdifficulttosinterdopedceriabysolidstatereactioninair .TheCe0 .9RE0 .1O2 -δelectrolytematerialswerepreparedbythesol gelmethod .Thesinteringtemperatureofthesamplescandecreasetoabout 4 0 0K .Theionicconductivityandlinearthermalexpansionpropertiesofsol gelpreparedCe0 .9RE0 .1O2 -δinawidetemperaturerangewerein vestigated .Thepowder…     

Study on stability of RECo5 phases（RE=Dy,Gd）

The eutectoid decomposition reaction that occurred in RECo5 phases ( RE=Dy and Gd ) at low temperature was discussed and confirmed by X-ray powder diffraction (XRD), differential thermal analysis, and scanning electron microscopy. The decomposition temperature of the GdCo5 and DyCo5 were identified as 805.8 and 900℃, respectively. The GdCo5 and DyCo5 phases could not be found in the isothermal section of Gd-Dy-Co ternary system at 800 K. Reasons for the absence of the RE2Co7 phase in the XRD patterns were discussed in detail.     

Properties and Application of Double Alkali Earth Doped Ce0.9Ca0. 1 - xSrxO1.90

A series of solid solution material based on ceria, Ceo.9Cao.l-xSrsOi.90(x = 0, 0.04, 0.05, 0.06), were synthesized by a solid reaction method. Ceria doped with two alkali earth dements has cubic fluorite structure. The ionic conductivity of these materials at high temperature was studied by impedance spectra, and an increasing effect of ionic conductivity was found. A maximum conductivity is achievedwhen the effective ionic radius is near to the critical radius (0. 1106 nm). Some fuel cells were made using these materials as electrolyte. The output power and current of the SOFC with the electrolyte of double doped ceria are better than those of YSZ and single doped ceria, and the open-circuit-voltage of the double doped ceria is also higher than that of the single doped ones.     

Study on Copolymerization of Rare Earth－Carboxylic Acid Complex

Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polymer with different rare earth contents. Its glass-transition temperature and heat stability were analyzed by TG and DTA. Infra-red detector was used to show its structure. The effect of rare earth complex prepared by different methods on copolymerization and properties of copolymers was also discussed.     

Preparation and Structure of Mg2-xRExNi （RE = La, Ce, Pr, Nd, Y） Ternary Alloys

A series of Mg2-xNdxNi (x =0.05, 0.1, 0.2, 0.3) alloys and Mg1.95RE0.05Ni (RE= La, Ce, Pr, Nd, Y)ternary alloys were prepared by ball milling of mixted powder of Mg, Ni, RE and sintering under the protection of argon. XRD analysis shows that Mg2-xNdxNi (x = 0.05, 0.1 ) and Mg1.95RE0.05Ni consist of single phase with the same crystal structure as Mg2Ni. While three-phase alloys including Mg2Ni, NdNi and NdMgNi4 were formed in Mg1.8Nd0.2Ni and Mg1.7Nd0.3Ni alloys respectively. The lattice constants of Mg2Ni in those ternary alloys were calculated. The decomposition of Mg2Ni occurs in the milling process of Mg2Ni and Mg1.95RE0.05Ni alloys respectively. For the latter, another earlier reaction occurs in milling process, which means that atoms of RE are separated from crystal structure of Mg2Ni and form relevant oxides by combination with oxygen existed in argon atmosphere.     

Study on Preparation and Property of Poly－Aminosilicone－Rare Earth Composite

The poly-aminosilicone-rare earth composite was prepared by poly-aminosilicone cross-linked with rare earth and active silanol. The thermal stability of the composites was studied by thermogravimetric analysis (TG). Force condition of the composites in electric field was analyzed and relative polarizability was derived. It is found that the composites containing different rare earth ions have different relative polarizability. The experiment results reveal that organosilicon materials with different electrical performance can be obtained by this way. Meanwhile, the absorption and flourescene spectrum of composites were also investigated. Compared to rare earth chloride, the spectrum properties of the composite are changed obviously. The possible reasons for these phenomena were discussed.     

Syntheses and Crystal Structure Characterizations of New Rare Earth Copper Bismuth Compounds RE CuBi2 （RE = La, Gd and Dy）

The tide new compounds with chemical formula RE CuBi2 were synthesized by arc melting method followed by annealing. The crystal structures refined using Rietveld method and X-ray powder diffraction data show to be isotypic to CaMnBi2 structure type with space group P4/nmm (No. 129). The unit cell parameters are a=0.457946(4)nm,c =0. 98858(2) nm, V =0. 207319(8) nm^3 for LaCuBi2, a = 0.449279(9) nm, c = 0. 95958(4) nm, V = 0. 19369(2) nm^3 for GdCuBi2 and a =0. 447680(7) nm, c =0. 95124( 3 ) nm, V = 0. 190644(5 )nm^3 for DyCuBi2 respectively, showing lanthanide contraction. The structure is characterized by layers of edge-shearing CuBi4 tetrahedron and covalently bonded Bi square net separated by rare earth atoms.     

Thermogravimetric Study on Oxygen Adsorption/Desorption Properties of Double Perovskite Structure Oxides REBaCo2O（5＋δ）（RE= Pr,Gd,Y）

The oxygen adsorption/desorption properties of double perovskite structure oxides PrBaCo2O5＋δ,GdBaCo2O5＋δ,and YBaCo2O5＋δ were investigated by the thermogravimetry（TG）method in the temperature range of 400~900 ℃.The calculated oxygen adsorption/desorption surface reaction rate constants ka and kd of these double perovskite structure oxides were larger than the commonly used cubic perovskite oxides,such as Ba0.95Ca0.05Co0.8Fe0.2O3-δ and Ba0.5Sr0.5Co0.8Fe0.2O3-δ,whereas,the oxygen permeation flux was comparable to that of the latter,which was attributed to the smaller difference of oxygen vacancy in oxygen and nitrogen atmosphere（Δδ/Vmol）in these double perovskite structure oxides.The large oxygen adsorption/desorption rate constants of GdBaCo2O5＋δ and PrBaCo2O5＋δ made them nice catalyst coating materials,on other membrane surfaces,to improve the oxygen permeability.     

Oxidative dehydrogenation of ethane over RE-NiO （RE=La, Nd, Sm, Gd） catalysts

RE-NiO(RE=La,Nd,Sm,Gd) catalysts were prepared by a modified sol-gel method and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),BET surface area analysis,H 2 temperature-programmed reduction(H 2-TPR),and O 2 temperature-programmed desorption(O 2-TPD).The oxidative dehydrogenation of ethane(ODHE) to ethylene was applied to evaluate catalytic performance of the samples.The results showed that the doping of RE affected the physicochemical properties of the catalysts.The strong interaction between Gd and NiO played an important role in the lessened reducibility and the distribution of adsorbed oxygen species,consequently influenced the catalytic performance.The best yield to ethylene of 29% was obtained over the Gd-NiO catalyst with an ethane conversion of 56%.     

Magnetic Entropy Change of （Gd1-xREx）5Si4（RE = Dy, Ho） Alloys

Magnetic Entropy Change of (Gd_(1-x)RE_x)_5Si_4(RE=Dy, Ho) Alloys     

Effects of La0.8 Sr0.2 Mn（Fe） O3 - δ Protective Coatings on SOFC Metallic Interconnects

SUS430 （16% - 17% （mass fraction） Cr） can be used as interconnects for solid oxide fuel cells （SOFCs） that operate at lower temperatures （ 〈 800 ℃ ）. However, oxidation of steel can occur readily at elevated temperatures leading to the formation of Cr2O3 and spinel （Fe3O4） and thus greatly degrades the performance of the fuel cell. The aim of this work was to reduce oxide growth, in particular, the Cr2O3 phase, through the application of La0.8Sr0.2MnO3-δ （LSM2O） and La0.8Sr0.2FeO3-δ（LSF20） coatings by atmospheric plasma spraying technology （APS）. Oxide growth was characterized by using X-ray diffraction （XRD）, scanning electron microscopy （SEM） with an energy dispersive X-ray （EDX） analyzer. During oxidation of fifty 20 h cycles at 800 ℃ in air, the samples with coatings remained very stable, whereas significant spallation and weight loss were observed for the uncoated steel. LSF20 presents apparently advantages in reducing oxidation growth, interface resistance and inhibition of diffusion of chromium. After exposure in air at 800 ℃ for 1000 h, the interfacial resistance of LSF20-coated alloy is lowered by more than 23 times to that of LSM20-coated layer.     

La0.65RE0.10Mg0.25Ni3.5Si0.15(RE=La,Ce,Pr,Nd,Sm)储氢合金的电化学性能及EIS分析

通过感应熔炼制备La0.65RE0.10Mg0.25Ni3.55i0.15(RE =La,Ce,Pr,Nd,Sm)合金.采用X射线衍射方法分析了合金的相结构,研究了其电化学性能,并采用电化学阻抗谱分析了合金电极的放氢动力学特性.研究结果表明,合金是以LaNi5、LaNi3为主相的多相结构,同时合金中少量的Si元素与Mg和Ni元素形成了少量的Mg2 Si相和Ni2Si相.Ce,Pr,Nd,Sm部分替代La以后,合金的放电容量下降,Ce的替代使合金容量大幅度降低.对于本系列合金,La被其他稀土元素部分替代后,合金经过100次循环后的容量保持率略有下降,但除了Pr元素以外,变化值均较小.合金电极的电化学阻抗谱分析表明,中低频区的容抗弧半径依次为Ce ＞La＞ Nd ＞Sm ＞Pr,这表明采用Nd、Sm、Pr替代La后合金电极在碱液中放电过程电荷传递电阻Rct减小,即合金表面活性增加,但Ce替代却导致Ret急剧增大,这可能与Ce在碱液中易形成氧化物降低了合金的表面活性有关.     

Electrical Properties and Applications of （ZrO2）0.92 （Y2O3）0.08 Electrolyte Thin Wall Tubes Prepared by Improved Slip Casting Method

8%(mole fraction) yttria-stabilized zirconia electrolyte thin wall tubes were prepared by improved slip casting method. The length and wall thickness of the tubes are 266 mm and 0.4 - 0.9 mm, respectively and the relative density is 96.7 %. The microstructure and electrical properties of samples sintered at different temperatures were studied using SEM and ac impedance spectroscopy. The effect of sintered density, grain and grain boundary on the electrical properties of the samples was analyzed. The research results show that the density of the samples increases gradually with increasing sintering temperatures. The microstructurc of samples strongly influences its electrical properties, and the electrical prop.erties of samples enhance with the increase of sintered density. The ionic conductivity of grain and grain boundary is increased as the sintering temperature increases. Better sinterability of the samples was obtained at the sintering temperature of 1650℃. The maximum open circuit voltage and short circuit current for single cell is 0.946V and 1.84A, respectively. The maximum output power of single cell is 0.46W at the temperature of 850℃.     

Dependence of Magnetic Properties of Rapidly Quenching （Nd, Pr）x（FeCoZr）94-xB6 Bonded Magnets on Rare Earths Content

By using sub-everquenching and annealing method which has a wide processing window, (Nd, Pr)x(Fe-CoZr)94-xB6(x=12, 10.5, 10, 9) bonded magnets were prepared and the effect of rare earths content on magnetic properties was investigated. Being spun at sub-ove, quenching speed the as-spun ribbons consist of amorphous phases mixed with fine crystallites. After crystallization under optimum annealing conditions and bonded with 3.25%(mass fraction) epoxy, the magnets obtained the optimum magnetic properties. The rare earths content directly determines the magnetic properties. With the reduction of rare earths content, Br increases but Hci and (BH)max decrease, x=10 is the critical value for the magnetic properties change. Below this value, Br increases slowly meanwhile Hci and (BH)max decrease strongly because alloy contains extra fractions of soft magnetic phase which are not coupled with the hard magnetic phase. This experimental result is consistont with the calculated results using the model of volume fraction of soft magnetic phase coupled completely suggested.     

Study on Luminescence Properties of a Novel Rare Earth Complex Eu（ TTA）2 （N-HPA） Phen

A novel rare earth complex Eu（TTA）2（N-HPA）Phen （TTA = thenoyltrifluoroacetone, N-HPA = N-phenylanthranilic acid, and phen = 1,10-phenathroline ）, which contains three different ligands, was synthesized. The Eu complex was blended with poly N-vinylcarbazole （PVK） in different weight ratios and spin coated into films. The luminescence properties of films were investigated and energy transfer between PVK and the complex was discussed. Multilayer structural devices consisting of ITO/PVK： Eu （TTA）2 （N-HPA） phen/BCP/Alq3/Al were fabricated with PVK ： Eu （TTA）2（N-HPA） as light-emitting layer. Increasing the concentration of Eu in the PVK thin film would inhibit the emission of PVK to different degrees. Finally, the pure red luminescence of europium（ Ⅲ ） was observed when the doping weight ratio was approximately 1 ： 5, which indicated an effective energy transfer from PVK to rare earth complex.     

Effect of Rare Earth （Niobium） on Costed and Hot-Rolled Microstructure and Properties of Heavy Rail Steels

Effect of Rare Earth (Niobium) on Costed and Hot-Rolled Microstructure and Properties of Heavy Rail Steels     

Thermochemical Properties of the Complexes RE(HSal)_3·2H_2O (RE=La,Ce,Pr,Nd,Sm)

Nowadays great attention has been paid to thelanthanide aromatic carboxylates owing to their novelstructures and potential applications in material sci-ences as superconductors ,magnetic materials ,andlu-minescent probes[1 ~6].The luminescence , mechanismof thermal descomposition , stability constants , andother properties of some lanthanide complexes withsalicylic acid have been reported in literatures[7 ~10].And thermochemistry of other lanthanide complexes hasbeen described[11 ,12]. Thermoc…     

Synthesis and Study on Physical Properties for Magnetic Superconductor RESr2RuCu2O8（RE = Gd and Eu）

Single-phase magnetic superconductors RESrzRuCuzOs(RE = C,d and Eu) were successfully synthesized and investigations on their physical properties were carried out. It is found that the structure of the compounds is similar to that of YBa2Cu307 and its superconductivity coexists with weak ferromagnetic order in both compounds. The compounds exhibit magnetic order below TM = 130 and 136 K and superconducting below TC^onset = 35 and 46 K, respectively, for RE = Eu and Gd samples. There is slight difference in the magnetic properties between RE = Euand C,d compounds owing to various magnetic moments for C,d3 and Eu3 .     

Spectroscopy Study on Crystal Structure of Ce（NO3）3 （phen）2 and Interactions of Ce（NO3）3 （phen）2 with DNA

Inrecentyears ,Komiyaetal.[1] havefoundthatrareearthsionsmaybeoneofthestrongestcutre agentsofnucleicacids .Theexperimentalresults ,thatrareearthsrepresscancersonwholeanimalbodiesandonhumanbodies(invitro) ,indicatedthatrareearthselementsactuallyhavestrongf…