Monazite in a granite pegmatite from Yamanoo, Sakuragawa, Ibaraki Prefecture, Japan has been examined terms of U, Th, Pb, and rare earth element (REE) chemistry by electron microprobe analysis. This occurs as lenticular vein the Kabasan granitic body. Oscillatory sector zoning were observed back-scattered images. An averaged empirical formula was (Ce0.286Nd0.180Sm0.104La0.077Y0.069Pr0.041Gd0.06...

by Dave McCarthy In a news conference held y e s t e r d a y F a th e r T heodore H esburgh, C .S.C., p residen t o f N o tre D am e, to ld new sm en w hy, w hen 21 colleges and universities (inc lud ing M IT, C ornell, Vassar, H oly C ross, and D uke) have decided to suspend classes from fo u r days to tw o w eeks to allow s tu d en t political cam paigning, N o tre Dame had postponed a refere...

Nghiên c?u v?i m?c tiêu mô t? ??c ?i?m xét nghi?m b?nh h?c c?a nhân ung th? ??i tr?c tràng ??n khám t?i vi?n ??i Y Hà N?i n?m 2020. Nhóm nghiên s? d?ng ph??ng pháp c?t ngang trên 115 làm gi?i ph?u b?nh, có b?n là và k?t qu? bi?u khoa Gi?i - B?nh trong th?i gian t? tháng 1/2020 12/2020. K?t cho th?y v? trí kh?i u g?p nhi?u nh?t (56,5%), ti?p theo sigma, 27%. G?p m?i t?n th??ng th? ?ó sùi loét 2 ...

We have investigated the migration behaviors of uranium (U) and thorium (Th) in Earth and other terrestrial planets. Theoretical models of U and Th migration have been proposed. These models suggest that the unique features of Earth are closely connected with its unique U and Th migration models and distribution patterns. In the Earth, U and Th can combine with oxidative volatile components and...

Fluorapatite from Cerro de Mercado, Durango, Mexico has been used in several important diffusion studies aimed at calibrating the closure temperature of the (U-Th)/He apatite thermochronometer and has become a de facto standard for (U-Th)/He laboratories. Nevertheless, replicate laser fusion analyses of small crystal fragments of the "Durango fluorapatite" typically yield a range of (U-Th)/He d...

[With 32 Figs. & 4 Tables] I. In tro d u c tio n ........................................................................................................................ 216 II . R ev iew of l i t e r a t u r e ...............................................................................................................216 II I . M a te ria l, m e th o d s and t e c h n i q u e ..................

A b str a c t C o n tro l in te n siv e IC s p o se a sign ifican t ch allenge to th e users o f fo rm a l m e th o d s in d esig n in g h ardw are. T h ese IC s h a ve to s u p p o r t a w id e v a r ie ty o f req u irem e n ts in clu d in g synchronous and asynchronous o p era ­ tion s, p o llin g an d in te rru p t-d riv e n m o d e s o f o p era tio n , m u ltip le con cu rrent th rea d s o...

We report the application of high-resolution in situ 238U-230Th disequilibrium dating to pyrochlore [(Ca,Na,REE,Th,U)2(Nb,Ti,Ta,Zr)2O6(OH,F)]. Compositionally zoned pyrochlore is an accessory phase in intrusive carbonatitic syenites, which were ejected as cognate clasts during the eruption of the phonolitic Laacher See volcano, East Eifel, Germany, 12.9 ka ago. Separated individual pyrochlore c...

Th ermodynam ic properties of sm all stru ctures, su ch as the m eltin g poin ts and the process of m ass tran sport, can be con sid erably different compared to materia l in th e bu lk form . Calorim etry is th e standard experim en tal techniqu e u sed to m easu re thermodynam ics properties. Howev er, th is techniqu e is extremely difficu lt to u se for th e study of sm all stru ctures becau...