电感耦合等离子体原子发射光谱法测定镨钕钆合金中镨钕钆配分量

镨钕钆金属是钕铁硼合金的新兴原料,具有有害元素含量低、产品成分稳定、成本低的优势,而快速准确地测定镨钕钆合金中镨、钕、钆配分量对产品的质量控制具有重要意义。实验采用硝酸溶解样品,在仪器的最佳分析条件下,选择Pr 418.948nm、Nd 445.156nm、Gd 342.246nm为分析谱线,使用电感耦合等离子体原子发射光谱法(ICP-AES)对镨钕钆合金中镨、钕、钆配分量进行测定。讨论了溶解样品条件、共存元素干扰等对测定的影响。结果表明,硝酸易于溶解镨钕钆金属夹杂碳化物和氮化物。样品中共存稀土元素和铁、钙、镁、铝、硅、钼、钨等非稀土元素对镨、钕、钆配分量测定的影响可以忽略。实验方法用于测定3个镨钕钆合金中镨、钕、钆配分量,结果的相对标准偏差(RSD,n=11)为0.070%~0.56%;分别按照实验方法与X射线荧光光谱法(XRF)测定镨钕钆内控标样中镨、钕、钆配分量,两种方法的测定结果一致。     

微波消解-电感耦合等离子体原子发射光谱法测定稀土合金渣中主要稀土氧化物

提出了微波消解-电感耦合等离子体原子发射光谱(ICP-AES)同时测定稀土合金渣中氧化镧、氧化铈、氧化镨、氧化钕、氧化钐和氧化镝等主要稀土氧化物的分析方法。考察4种不同的消解试剂体系,优化了消解参数并选择了合适的分析线。结果表明,在以下条件下样品的消解效果最好：以HNO₃-HCl-HF-H₂O₂（V(HNO₃)∶V(HCl)∶V(HF)∶V(H₂O₂)=4∶2∶2∶1）作为消解试剂,采用四段升温的消解程序,设定的最低温度为160 ℃,最低压力为1.5 MPa,最高温度为225 ℃,最高压力为3.5 MPa,每段的最大温差不超过25 ℃,最大压差不超过1 MPa。在选定的仪器参数下,以408.671,413.765,390.843,401.255,359.260,353.171 nm 波长的谱线分别作为La,Ce,Pr,Nd,Sm,Dy的分析线,用稀土氧化物绘制校准曲线,ICP-AES法测定消解液中上述氧化物。测定结果的相对标准偏差在0.44%～0.98% 范围,加标回收率在94%～106%之间。     

Lubricity of Rare Earth Compounds in Oil

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Research on Rare Earth Encapsulated Luminescent Material

A new method of preparation of irradiative material by using rare earth as luminophor and inorganic powder as base nucleus was presented.Rare earth was used to make colloid, which was mixed with base nucleus solution,where deposition/attachment reaction took place and rare earth was adhered onto the surface of base nucleus, hence yielding a new rare earth encapsulated irradiative material.Fluorescent spectrum analysis shows that this material possesses two emission peaks, one within 400 ～ 500 nm and the other within 580 ～ 700 nm, reflecting the luminous characteristics of original rare earth material.     

灼烧温度对镨钕二元氧化物粒度和形貌影响的研究

以氯化镨钕溶液为原料液,分别用草酸、碳酸氢铵和碳酸钠为沉淀剂制备镨钕草酸盐和碳酸盐,在900℃~1500℃范围内不同灼烧温度下制备出镨钕二元氧化物,利用粒度仪和扫描电镜进行测试,研究了灼烧温度对稀土氧化物的粒度和形貌特征的影响;结果表明,灼烧温度的提高对中位粒径D50和粒度分布R变化影响不同,改变灼烧温度对镨钕二元氧化物的形貌影响较大。     

偶氮氯膦Ⅲ光度法快速测定球铁中的残余稀土

采用草酸隐蔽—偶氮氯膦Ⅲ光度法测定球铁QT400—18中残余稀土，在pH值为0．4～0．9的硫硝混合酸介质中，偶氮氯膦Ⅲ能与稀土形成蓝色配合物，最大吸收波长位于670nm处，稀土含量在0．018％～0．058％范围内符合比耳定律。该方法分析速度快，准确度高，可以满足生产需要。     

新试剂二溴羧基偶氮氯膦用作镁、稀土的显色剂Ⅱ.光度测定稀土的研究和应用

本文建立了一种测定球墨铸铁中稀土总量的分析方法.在硝酸介质中,稀土元素与二溴羧基偶氮氯膦生成蓝色配合物,其最大吸收峰在645nm处.比尔定律范围是10～16μgRE/25ml,方法选择性好,可不经分离直接测定球墨铸铁中稀土总量.     

电感耦合等离子体原子发射光谱法测定铝硅活塞合金中镧铈镨钕钇

采用硝酸和氢氟酸溶解样品,高氯酸冒烟赶氟避免生成氟化稀土沉淀,选择La 333.749nm、Ce 456.236nm、Pr 417.939nm、Nd 406.109nm及Y 371.030nm作为分析线,扣除背景点消除基体干扰,运用干扰系数法克服谱线间干扰,通过基体匹配法配制标准溶液系列消除基体效应的影响,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定铝硅活塞合金中镧、铈、镨、钕和钇。结果表明:镧、铈的测定范围在0.01%~2.00%,镨、钕、钇的测定范围在0.005%~2.00%,校准曲线线性相关系数不小于0.9998。方法中各元素检出限为0.0003%~0.0018%。实验方法用于测定稀土铝合金合成试样中镧、铈、镨、钕和钇,结果的相对标准偏差(RSD,n=6)在0.50%~2.4%之间,加标回收率在94%~105%之间。实验方法用于含有稀土的铝合金标准样品中镧、铈、镨、钕和钇的测定,结果与电感耦合等离子体质谱法(ICP-MS)测定值相吻合,测定的稀土总量RE与认定值也相吻合。     

Study on spectroscopic properties of GdOBr:RE3+ (RE=Eu, Tb, Ce)

Rare earth ions doped gadolinium oxybromide phosphors GdOBr:RE3 (RE=Eu, Tb, Ce) were synthesized by the method of solid-state reaction at high temperature, and the VUV-VIS spectroscopic properties of the phosphors were systematically investigated. Under the excitation of VUV or UV source, the phosphors doped with Eu3 and Tb3 show a bright and sharp emission at around 620 nm corresponding to the forced electric dipole 5D0→7F2 transition of Eu3 , and at around 544 nm corresponding to the 5D4→7F5 transition of Tb3 , respectively. For GdOBr:Ce3 , a broader and intense emission spanned 370-500 nm corresponding to the d-f transition of Ce3 was observed. The excitation spectra were also analyzed.     

Extraction and back-extraction behaviors of 14 rare earth elements from sulfuric acid medium by TODGA

The unique physical and chemical properties of rare earth elements lay the foundation for their extensive application. N,N,N',N' Tetra-octyl-3-oxopentanediamide(TODGA) is excellent in its ability of extracting rare earth elements and it is favored for green initiative. In this paper, the extraction and back-extraction of14 rare earth elements by TODGA were studied. Experiments show that in conditions of 6 mol/L sulfuric acid, the extraction temperature of 25 ℃,the phase ratio of 1:1 and 0.04 mol/LTODGA(aviation kerosene as the diluent), the extraction rates of 14 rare earth elements including lanthanum, cerium, praseodymium,neodymium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium were 99.00%-99.73%. Mixed with hydrochloric acid and nitric acid(HCl 3.5 mol/L, HNO_30.5 mol/L), the recoveries of the 14 rare earth elements are 91.52%-99.91% when the extraction temperature is 25 ℃ and the ratio is 1:1. The following application is based on the optimum conditions above with practical samples(from the roasting production line of China North Rare Earth High-tech Company Limited) for extraction and back-extraction experiments. Experiments show that TODGA has excellent enrichment effect on 14 rare earth elements, the extraction rates are 91.36%-99.80%, the back-extraction rates are 87.29%-99.64% and the total recoveries are 81.19%-99.44%.     

2,4-二氯-6-溴偶氮氟膦与稀土的显色反应及其应用

摘 要：对显色剂2,4-二氯-6-溴偶氮氟膦与稀土元素在微波催化下的显色反应进行了研究。在硝酸及少量吡啶介质中,于40℃的微波水浴中加热催化8 min,试剂与各稀土发生显色反应,形成稳定的蓝色配合物。典型稀土元素La、Ce与显色剂的配合比均为1︰3,各稀土配合物的最大吸收波长位于632～636 nm,表观摩尔吸光系数相近,ε为 0.89～1.15×105 L?mol-1?cm-1。以634 nm作为测定波长,改变混合稀土的配分进行试验,结果表明,La、Ce、Y的比例对稀土总量测定的影响不显著。加入四元混合掩蔽剂,采用本方法对岩石等实际样品中稀土总量进行测定,相对标准偏差（RSD, n=5）为2.0%～2.4%,回收率为 93%～98%。     

Investigations on luminescence of rare earths doped CaTiO3:Pr3+ phosphor

Calcium titanate doped with praseodymium was prepared through solid state reaction and it exhibited intense red emission at 612 nm. Phosphors were characterized for photoluminescence, thermo-luminescence and afterglow emissions. Study of effects of rare earths on photoluminescence as well as afterglow intensity was reported. Presence of gadolinium enhanced luminescence. Presence of some monovalent ions enhanced both afterglow and photoluminescence emission. Thermo-luminescence glow curves were analyzed and ...     

Structure and Waveguide Properties of Sol-Gel Derived Gd2O3 Films

Pure and rare earth doped gadolinium oxide (Gd2O3) waveguide films were prepared by a simple sol-gel process and dip-coating method. Structure of Gd2O3 films annealed at different temperature was investigated by X-ray diffraction and transmission electron microscopy. Oriented growth of (400) face of Gd2O3 has been observed when the films were deposited on amorphous substrate. The refractive index and thickness of films were determined by m-lines spectroscopy. The laser beam (λ= 632.8 nm) was coupled into the film by a prism coupler and the propagation length is about 3.5 cm. Luminescence properties of europium ions doped films were measured by waveguide fluorescence spectroscopy, which shows disordered environment for Eu^3 at 400℃.     

牦牛坪西部矿区稀土矿工艺矿物学研究

以牦牛坪西部矿区的氟碳铈矿为研究对象,利用 X 射线衍射分析、扫描电镜、光学显微镜、MLA矿物自动测量系统等分析手段对其进行了较为系统的工艺矿物学分析。结果表明,该矿石中稀土元素以镧、铈、钕及镨四种元素为主,总稀土氧化物（TREO）品位为 6.9%。该矿样中稀土矿物种类主要为氟碳铈镧矿,稀土矿物品位较高,属高价值稀土矿。其他矿物主要为重晶石、萤石、长石和石英等,其次是云母、角闪石及褐铁矿、赤铁矿等。矿石中氟碳铈镧矿、重晶石、萤石具不均匀中细粒嵌布的特征,需要细磨至 -0.019mm 才能达到单体解离。     

SWRS82B钢中稀土元素对氧化铝改性的晶体学

 为了深入研究与控制SWRS82B钢中氧化铝夹杂,针对添加稀土元素铈研究其对氧化铝的改性问题,通过热力学以及边-边匹配模型对稀土夹杂物的析出条件和Al₂O₃与稀土氧(硫)化物之间、γ-Fe和稀土氧(硫)化物之间的原子间错配度进行计算,探究稀土铈夹杂物作为Al₂O₃和γ-Fe异质形核的有效性,进而证明稀土铈元素对B类氧化铝夹杂物改性的有效性,提高钢材性能。计算结果表明,在0~2 000 K的温度区间上,生成CeAlO₃夹杂物反应的吉布斯自由能最低,且在同等条件下铈氧(硫)化物生成的可能性偏低,稀土铈氧(硫)化物可以作为Al₂O₃异质形核的核心,且稀土铈氧(硫)化物可以作为γ-Fe异质形核的核心;Al₂O₃可在稀土铈氧(硫)化物上有效形核,且Al₂O₃优先在Ce₂O₂S上发生异质形核;γ-Fe可在Al₂O₃和稀土铈氧(硫)化物上有效形核,且γ-Fe优先在Al₂O₃上发生异质形核,使得形状不规则的氧化铝夹杂物转变为近球形的铈铝酸盐夹杂,揭示SWRS82B钢中非金属夹杂物的变性机理,为提高SWRS82B钢中脆性夹杂物转变为塑性夹杂物处理的实际效果提供理论依据。     

电感耦合等离子体原子发射光谱法测定赤泥浸出液中稀土元素

对赤泥浸出液中稀土元素含量进行测定可以指导研发人员初步判断赤泥中的稀土总量。采用5 mol/L盐酸浸取赤泥中稀土元素镧、铈、镨、钕、钪、钇,并采用电感耦合等离子体原子发射光谱法(ICP-AES)进行了测定。以功率、辅助气流量、分析泵速和积分时间为考察因素,各元素分析谱线的发射强度为考察指标,设计了L₉(3⁴)的正交试验,确定了电感耦合等离子体原子发射光谱仪的最佳工作条件为功率950 W、辅助气流量为0.50 L/min、分析泵速为100 r/min、积分时间为10 s。使用标准加入法绘制校准曲线,消除了基体及杂质元素对待测稀土元素测定的影响。各待测元素校准曲线的线性相关系数均不小于0.999 9,方法中稀土元素镧、铈、镨、钕、钪、钇的检出限在0.002 4～0.013 mg/L之间。按照实验方法测定赤泥浸出液实际样品中稀土元素镧、铈、镨、钕、钪、钇,结果的相对标准偏差(RSD,n=6)为0.21%～1.2%,回收率为96%～114%。采用实验方法和电感耦合等离子体质谱法(ICP-MS)分别对赤泥浸出液中的稀土元素镧、铈、镨、钕、钪、钇进行测定,两种方法的测定结果基本一致。     

循环伏安法测定纳米晶贮氢合金中氢扩散系数

用双辊快淬法制备了纳米晶稀土贮氢合金,XRD图谱表征为结晶较好的CaCu5六方结构,Scherrer公式计算晶粒大小约为40nm。利用循环伏安法测定了纳米晶稀土贮氢合金电极中的氢扩散系数(DH=1.67×10-7cm2/s),由于纳米晶粒具有较高的结晶度和细小的晶粒尺寸,高密度晶界为氢在合金内部的扩散提供快速通道,提高了贮氢合金的吸放氢效率,从而提高了氢的扩散性能,使电极中氢的扩散系数增大。     

重铬酸钾溶液浸取-电感耦合等离子体原子发射光谱法测定稀土镁硅铁合金中氧化镁

采用40 g/L重铬酸钾溶液作为氧化镁的浸取剂, 在室温下震荡样品30 min, 过滤后选择279.553 nm、280.270 nm、285.213 nm 3条谱线中的任一条谱线作为分析线, 在优化仪器参数的条件下用电感耦合等离子体原子发射光谱法(ICP-AES)测定滤液中的氧化镁, 从而建立了稀土镁硅铁合金中氧化镁的测定方法。方法的检出限(质量分数)分别为0.003 0%(279.553 nm)、0.002 7%(280.270 nm)、0.0043%(285.213 nm), 测定下限(质量分数)分别为0.030%(279.553 nm)、0.027%(280.270 nm)、0.043%(285.213 nm), 铁、钾、铬、稀土的允许量(μg/mL)分别为150、2 000、6 000、200, 试液中2 g/L重铬酸钾产生基体效应对测定的影响可以忽略不计。方法应用于实际样品中氧化镁的测定, 测定值与原子吸收光谱法的测定值相符, 测定结果的相对标准偏差小于5%。     

氧化钕和氧化镨钕在大气中的吸水特性研究

研究了氧化钕和氧化镨钕的吸水特性及吸水稳定后物质的结构与形态表征,通过增重试验及增重稳定后物质的X射线衍射试验,讨论了氧化钕和氧化镨钕吸水的一般动力学过程,并分析了影响吸水速率的因素。研究表明,氧化钕和氧化镨钕的吸水过程为未反应核模型,Lageren准一级、HO准二级动力学方程仅能对其诱导期之后的某个阶段拟合较好。氧化镨钕明显异于氧化钕,吸水产物孔隙率减小,吸一定水后出现类似"饱和"的现象。     

Comparison of thermoluminescence spectra of MgB407 doped with dysprosium and manganese

A series of magnesium borate phosphors MgB4O7：Dy, MgB4O7：Mn and MgB4O7：Dy,Mn were prepared and their ther-moluminescence （TL） emission spectra were measured. TL emission bands in 480, 575 and 660 nm at 200 and 360 oC were observed in the MgB4O7：Dy due to the transitions of the trivalent rare earth ions Dy3＋. The glow peaks of broad wavelength band around~580 nm at 180 and~290 oC were observed in MgB4O7：Mn due to the emission of Mn2＋ions. The main glow peak of MgB4O7 co-doped with Dy and Mn appeared in 580 nm at~360 oC. When MgB4O7 was co-doped with Dy （0.5 mol.%） and different concentrations of Mn （0.01 mol.%-1.0 mol.%）, the peak in 580 nm at 360 °C was intensified and broadened as the concentration of Mn increased, while the peaks in 480, 680 and 750 nm below 300 °C remained the characteristic emission of Dy3＋and were reduced in intensity. The emission spectra of the MgB4O7：Dy,Mn phosphor showed that the competitive de-excitation processes between Dy3＋and Mn2＋existed and the energy transfer occurred from Dy3＋to Mn2＋. These results meant that rare earth and Mn ions in MgB4O7：Dy,Mn might cause the formation of defects complex that dominated the traps and recombination.