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The chemical equilibrium constant for the formation of La(NO3)3·(n-C4H9O)3PO was 0.09, while that of Dy(NO3)3·(n-C4H9O)3PO was 0.68. The ascending sequence of chemical equilibrium constants for the simultaneous formations was La, Ce, Pr, Nd, Eu, Y, Sm, Gd, and Dy.关键词:......
in the nickel coating by XRD and this was due to the induced co-deposition of elements La and Ni. The reason maybe was that the special out-layer electronic structure of element La raised the polarization......
the effects of exogenous lanthanum (La) on Alternanthera philoxeroides (Mart.) Griseb under perchlorate stress, changes in the growth and physiological parameters were investigated in solution culture experiments under controlled conditions. Different concentrations of La (NO 3 ) 3 were used in our study. It was shown that 0.1 and 0.5mg/L La3+ alleviated the inhibition effect of perchlorate......
. Being a candidate orange/red emitting phosphor for orange and white light emitting diodes, La Sr2 Al O5:Sm3+ could be effectively excited by both near-ultraviolet(NUV) and blue lights with typical f-f... was obtained that electric dipole-dipole interaction was dominant for the energy transfer among Sm3+ ions. The critical distance for energy transfer among Sm3+ ions in La Sr2 Al O5 was calculated to be ca......
earths ore.In this work,the adsorption thermodynamics of REEs on kaolin were investigated thoroughly and systematically.The experimental results showed that the adsorption characteristics of La,Nd,Y on kaolin did fit well with the Langmuir isotherm model and their saturated adsorption capacities were 1.731,1.587 and 0.971 mg/g,respectively.The free energy change(ΔG)values were –16.91 kJ/mol(La),–16.05......
The lattice parameter a, c, unit-cell volume V and c/a ratio increased linearly with the La concentration. Determined by thermogravimetry analysis, the Curie temperature(TC), phase transition temperature and melting temperature of(Pr1–xLax)2Fe14B decreased linearly upon the La content. Based on the results of DSC measurements and X-ray powder diffraction examinations, the phase diagram......
Existence form of lathanum and its improving mechanism of visible-light-driven La-F co-doped TiO2Ruifen Wang1,Shengli An1,Jing Zhang1,Jinling Song1,Fuming Wang21. School of Materials and Metallurgy...">The existence form and effect of La on the phase composition,morphology,recombination of photocarriers,and optical absorptivity of La-F codoped TiO2 were investigated.Experimental results indicate......
退火时间对LaMgNi3.9Mn0.2合金的结构与气态吸放氢性能的影响陈亚方1,董小平1,2,马玉蕊1,李旭1,高腾远1,苏建文11. 河北大学质量技术监督学院摘 要:为了研究退火时间对LaMgNi3.9Mn0.2合金的结构和气态吸放氢性能的影响,采用XRD和SEM手段测试了合金的物相和微观结构,半自动Siever′s法测试了合金的吸放氢动力学曲线.实验结果表明,随着退火时间增加,合金中LaMg(NiMn)4主相含量降低,(La,Mg)(NiMn)5相含量增加.铸态及退火合金表面均由不同尺寸的柱状晶组成,具有明显的组织遗传效应;随着退火时间增加,合金柱状晶区域中La,Mg,Ni的含量差值都降低,元素分布更均匀,15 h与20 h退火合金的柱状晶晶间区域中Mn元素消失.铸态和退火合金第一次吸氢后达到相应......
升温到180℃并保持15min进行微波消解,以10ng/mL Cs溶液为内标,建立了电感耦合等离子体质谱法(ICP-MS)测定氟化铈中13种稀土杂质(La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu)含量的方法.实验表明,13种稀土杂质的线性范围为1.0100ng/mL,线性相关系数均不小于0.999 5,方法的检出限为0.0020.050μg/g.用所建立方法测定氟化铈粉末样品中La,Pr,Nd,Sm,Gd的结果与电感耦合等离子体原子发射光谱法(ICP-AES)基本一致.将方法应用于氟化铈粉末样品中13种稀土杂质的分析,相对标准偏差(RSD,n=7)均小于5.0%,加标回收率为95%105%.关键词:电感耦合等离子体质谱法;氟化铈;稀土元素;微波消解;......
入烧杯中,往溶液中加入氨水,以样品做载体,共沉淀分离除去钠盐及能与氨水形成络氨离子的金属元素,沉淀物用稀氨水洗涤,热稀盐酸溶解,以电感耦合等离子体原子发射光谱法(ICP-AES)测定试液中La,Ce,Sm,Eu,Gd,Tb,Ho,Er,Dy,Tm,Yb,Y,建立了含难熔金属岩石中12种稀土元素的测定方法.各元素校准曲线的线性范围为0.10~25μg/mL,方法的检出限0.20~1.0μg/g.按照实验方法测定含难熔金属岩石物料中La,Ce,Sm,Eu,Gd,Tb,Ho,Er,Dy,Tm,Yb,Y等12种稀土元素,结果的相对标准偏差(RSD,n=9)为3.2%~6.2%,加标回收率为90%~110%.实验方法可用于含难溶金属岩石中稀土元素含量为0.001%~0.50%(质量分数)的测定.关键词:碱熔;共沉淀分离;电感耦合等离子体原子发射光谱法(ICP-AES);含难溶金属岩石......