Light rare earth element enrichments in ureilites: A detailed ion microprobe study
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چکیده
منابع مشابه
A Re-examination of the Rare-earth-element Orthophosphate Standards in Use for Electron-microprobe Analysis
A re-examination of fourteen standards consisting of orthophosphates of the rare-earth elements, Sc and Y, grown at Oak Ridge National Laboratory in the 1980s and widely distributed by the Smithsonian Institution’s Department of Mineral Sciences, reveals that some of the material is significantly contaminated by Pb. The origin of this impurity is the Pb2P2O7 flux that is derived from the therma...
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Extended X-ray absorption fine-structure (EXAFS) spectroscopy is used to characterize the local coordination of selected rare-earth elements (Nd , Sm , Dy , Yb ) coprecipitated with calcite in minor concentrations from room-temperature aqueous solutions. Fitting results confirm substitution in the Ca site, but first-shell Nd-O and Sm-O distances are longer than the Ca-O distance in calcite and ...
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Background: In nuclear technology, the solvent extraction is an important step for recovery of rare earth materials, purification, radionuclide production, and preparation of nuclear reactor materials. Tributyl phosphate (TBP) and toluene are taken as extractant and diluent, respectively, for study of extraction efficiency for rare earth element like CeO2. Methods: In the present paper, idea of...
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ساموئل بکت بیشتر از هر نویسنده دیگری در نیم? دوم قرن بیستم با گفتارش زمان? ما را به آستان? از هم پاشیدگی کشانده است، آستانه ای که در آن مدرنیته با سرانجام گریزان اما غیرقابل اجتناب خود مواجه می شود. در این تحقیق روی مفهوم فردیت و محو آن در دوران پسامدرن تاکید شده و در طی آن سعی شده است که فردیت مدرن و پسامدرن در رمان های سه گانه بکت بررسی گردد. تحقیق حاضر یک بررسی کتابخانه ای و کیفی بر روی سه ر...
15 صفحه اولOverland Flow Using Rare Earth Element
14 15 Rare earth element oxides (REOs) have excellent potential for use as tracers in 16 erosion studies. Using laboratory and field experiments we aimed to develop and test 17 a simple application method for spreading REOs and to use REOs to determine the 18 source of sediment to concentrated overland flow paths. 19 Tracks left by farm machinery (tramlines) in fields act as concentrated flow 2...
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ژورنال
عنوان ژورنال: Meteoritics & Planetary Science
سال: 2000
ISSN: 1086-9379,1945-5100
DOI: 10.1111/j.1945-5100.2000.tb01980.x