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1.
The Canadian Certified Reference Materials Project announces the availability of reference uranium tailings sample UTS-1, -2, -3 and -4. Eighteen laboratories participated in the interlaboratory program for total iron, titanium, aluminium, calcium, barium, uranium, thorium, total sulphur, sulphate and arsenic. Eight laboratories participated in the inter-laboratory program for thorium-230, radium-226, lead-210 and polonium-210 in all four samples and for thorium-232, radium-228 and thorium-228 in UTS-1 and UTS-2. 相似文献
2.
The stability of geochemical reference materials is subject to breakdown due to mineralic component or particle size fraction segregation or to ambient oxidation. A statistical design is presented to the analyst for detecting such a breakdown as soon as possible to avoid the resultant degradation in his output. The application of this design to a base metal certified reference material, MP-1a, is illustrated. 相似文献
3.
H.F. STEGER G.H. FAYE W.S. BOWMAN R. SUTARNO 《Geostandards and Geoanalytical Research》1979,3(2):173-175
Under the Canadian Certified Reference Mate-vials Project (CCRMP), four new ore reference materials, one uranium ore BL-5 and three sulphide concentrates (CCV-1, CPB-1 and CZN-1) have been recently issued. The preparation, characterization and certification of these samples are briefly presented. 相似文献
4.
Henry F. STEGER 《Geostandards and Geoanalytical Research》1982,6(2):249-255
The history of a zinc-copper sulfide ore, RU-1, is presented to show quantitatively the serious effects of ambient oxidation on unprotected samples that led to its rejection for inued use as a reference material. It is shown that pyrrhotite, sphalerite and chalcopyrite are much more susceptible to oxidation than is pyrite, the major constituent. The preparation of another sample, RU-2, from the same ore body verifies that oxidation also occurs to an appreciable extent during the preparation stages. 相似文献
5.
The Canadian Certified Reference Materials Project announces recommended values for radium-226 activity in four reference materials previously certified for uranium. Thirteen laboratories participated in the interlaboratory program for DL-la, DH-la, BL-4a and BL-5. Four measurement techniques were applied. Procedural and instrument calibrations were performed with certified radium solutions from the National Bureau of Standards, thereby establishing traceability of the recommended values for radium-226 in DL-la, DH-la, BL-4a and BL-5. These reference ores are also shown to be close to, if not in, radioactive equilibrium. 相似文献
6.
安徽巢湖凤凰山剖面石炭系微相和层序地层特征 总被引：9，自引：1，他引：9
应用露头层序地层学基本原理和方法 ,对巢湖凤凰山石炭系剖面进行重新研究。巢湖凤凰山石炭系总厚度为79.0 2 m ,在这个剖面中可以识别出 6种主要岩相、18种微相和 11个三级沉积层序 ,其中六个三级沉积层序属于 I型沉积层序 ,三个属于 II型沉积层序 ,缺失第 9和第 10沉积层序。三级沉积层序在不同的古地理单元和不同的沉积环境中可以进行对比。根据各微相特征和成因 ,揭示了沉积间断面上存在的多期古岩溶现象。阐述了三级层序及其对应的三级海平面升降旋回的特征 相似文献
7.
塔里木盆地库鲁克塔格地区二叠纪末-中三叠世基性岩床的发现及其地质意义 总被引：2，自引：1，他引：1
新疆塔里木盆地东北缘库鲁克塔格地区的中寒武统莫合尔山组沉积地层中发现三条形成于二叠纪末到中三叠世的基性岩床。三条岩床沿沉积岩层面顺层侵入,按照从下到上的顺序,分别为辉绿岩床(厚3m)、辉长岩床(厚20m)和粗玄岩床(厚2.5m)。三条岩床的地球化学特征相似,稀土含量高(∑REE=210×10-6~297×10-6),轻稀土元素富集((La/Yb)N =13.54~17.96),Eu负异常不明显(δEu=0.97~1.21),Ce稍具正异常(δCe=1.11~1.25)。大离子亲石元素(Rb、Ba、Th、Sr)富集,Sr具明显正异常; Ta、Nb和Hf具负异常。低氧化度(0.13~0.40)。三条岩床为同源岩浆活动的产物,岩浆源于上地幔或下地壳,但有下陆壳成分混染。三个样品的MgO含量在4%~6%之间,Mg#值在37.6~55.6之间,固结指数SI值位于18.7~29.3之间,反映原始的岩浆经历了比较明显的分异作用。粗玄岩床K-Ar年龄为255.2±7.3Ma,辉绿岩床K-Ar年龄为242.8±5.7Ma,辉长岩床Ar-Ar年龄为229.7±3.7Ma。本次岩浆侵入事件发生在南天山洋闭合之后,构造背景为造山后碰撞伸展环境。 相似文献
8.
Henry F. STEGER 《Geostandards and Geoanalytical Research》1981,5(2):189-193
The Canadian Certified Reference Materials Project has amended its procedure in interla-boratory certification programs. The reasons for reducing to one from two the number of bottles of a candidate reference materials submitted to each participating laboratory are discussed. The effect of the smaller number of results of the one-bottle approach to be expected on the certified value and 95% confidence interval is shown to be minor. 相似文献
9.
New mean values for up to 11 major and minor and up to 11 trace elements in soils SO-1 to SO4 have been calculated by two procedures. Analytical results received by CCRMP subsequent to the certification program of 1979 were included. In one instance, the same procedure as used for certification wherein all results except those rejected on chemical and/or statistical considerations was followed, but little improvement over the 1979 calculations was obtained. The other procedure is proposed by the authors for use in identifying concentration range intervals wherein maximum interlaboratory consensus is observed. The application of this procedure has permitted the certification of the four soils for the content of 24 elements not previously certified. 相似文献
10.
The Canadian Certified Reference Materials Project reports recommended values of lead-210 activity in four uranium reference materials previously certified for uranium and radium-226. Eleven laboratories participated in the interlaboratory program for DL-1a, BL-4a, DH-1a and BL-5; three measurement techniques were applied. Procedural and instrumental calibrations were performed with a certified lead solution from Amersham International Corp., thereby establishing traceability of the recommended values for lead-210. Activity ratios for uranium-238. radium-226 and lead-210 demonstrate these uranium reference materials to be in secular equilibrium, within experimental uncertainties. 相似文献