共搜索到206条信息，每页显示10条信息，共21页。用时：0小时0分0秒480毫秒
structure(a) and density of state of atoms in (111) cleavage surface of fluorite(b) 图3所示为萤石(111)面能带结构图和原子态密度图.图中,萤石晶体的能带低能区在-18.0~-16.0 eV 区域,基本为Ca 离子的3s轨道的本征态组成,而在费米能级附近的价带主要由F离子的2p轨道贡献,在7.5~12.5 eV附近的导...(a) and fluorite(111) cleavage surface(b) (Unit: ) 从图4可以看出,白钨矿(001)表面临近Ca质点之间的间距为0.5245 nm,WO4基团团簇模型的W质点距离为0.5245 nm,Ca质点与O质点的最临近距离为0.2345 nm,表面上最邻近的不同WO4基团之间O质点距离为0.3412 nm.而萤石(111)面Ca质点之间的间距为0.3867 nm,最邻近F质点的间距为......
%, the main components of coating are the (Sn, Ce)O2 solid solution with rutile structure and (Ce, Sn)O2 solid solution with fluorite structure. When the molar fraction of SnO2 is 17%, the main component of the coating is (Ce, Sn)O2 solid solution with fluorite structure. Annealed at higher temperature than 450℃, CeO2 is found in the coating containing 83%Sn, and there is not SnO2 in the coating containing......
. The fluorite phase is the unique oxidation products for most of the Ce-La alloys. Key words: Ce-La alloy; phase diagram; thermodynamics; oxidation 1 Introduction During past few years, attention has been paid... system. Three solid solution phases, named as fluorite, A and H, existed in the CeO2-LaO1.5 system [8-15]. The fluorite, A and H phases originate from CeO2, A- and H-form LaO1.5. In the early studies......
their depressing effect on minerals containing Ca2+/Mg2+ gangues. Calcite, mixture of calcite and fluorite, and nickel ore were used in the flotation. And the depression mechanism was studied... exhibits strong depressing ability on calcite in almost zero yields at pH value of 9.8, and calcite can be depressed in the flotation of calcite/fluorite mixture for approximate 87% yield of fluorite......
, results from XRD analysis showed that samples calcined at 800 oC for 4 h possessed single-phase cubic fluorite structure, and the average grain size was found to be 36–45 nm. Further Raman spectral analysis indicated that oxygen vacancies should be present in the cubic fluorite structure of Ce0.8Sm0.12Pr0.08O2–δ, and Pr-doping seemed to increase their concentration significantly. AFM images showed......
, results from XRD analysis showed that samples calcined at 800 oC for 4 h possessed single-phase cubic fluorite structure, and the average grain size was found to be 36–45 nm. Further Raman spectral analysis indicated that oxygen vacancies should be present in the cubic fluorite structure of Ce0.8Sm0.12Pr0.08O2–δ, and Pr-doping seemed to increase their concentration significantly. AFM images showed......
are crystallized in a single fluorite structure.The crystalline size ranges from 9 to 24 nm, which increases with the increase of calcination temperature.The lower SEM images were characterized......
prepared by amorphous citrate gel method. XRD patterns indicate that a pure fluorite phase is formed at 800 ℃. The electrical conductivity and the AC impedance spectra were measured. XPS spectra show......
flowsheet were analyzed;process flows and parameters which could give consideration to four kinds of components were determined.TFe,rare earth oxide(REO),niobium and fluorite recoveries could reach......
contributes to the improvement of tungsten and fluorite recovery and the circulation of water and reagents, which benefits the environment.关键词:......
