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采用了单柱离子色谱法测ＭｎＯ２产品中无机离子杂质；提出了消除干扰的可行途径，将Ｌａ（ＯＨ）３加入后能同时消除进样峰的干扰和溶剂峰的出现。选用１．７５ｍｍｏｌ／Ｌ邻苯二甲酸１．７５ｍｍｏｌ／Ｌ三羟甲基氨基甲烷为混合淋洗剂测定Ｆ＾－，Ｃｌ＾－，ＮＯ３＾和ＳＯ＾２－４，其标准加入回收率为９５％－１０５％；ＲＳＤ（ｎ＝７）为２．４７％－８．０８％。 相似文献
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铀产品中杂质元素的含量测定在核法证学溯源分析或燃料元件厂质量检验中具有重要应用价值,保证测量的准确度主要在于控制流程空白、提高杂质元素的回收率。本文建立了戊基磷酸二戊酯(UTEVA)树脂快速分离铀与杂质元素、电感耦合等离子体质谱法(ICP-MS)测定杂质元素含量的系统流程。结果表明,UTEVA树脂对铀的吸附能力强,铀样品取样量为16.43 mg时,全流程对铀的去污因子大于3×105,9种杂质元素(锰钼镍铜铬铝钛钒镉)的回收率为95.1%~105.1%,国家标准物质GBW04205中杂质元素的分析结果与参考值在不确定度(k=2)范围内一致。本工作建立的分离流程对铀的去污效果好,特别适用于样品量少的情况下铀中杂质元素的分析,为核法证分析最终的归因溯源或燃料质量检验提供了技术支持。 相似文献
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Lars Olov Andersson 《Physics and Chemistry of Minerals》2006,33(6):403-416
Electron Paramagnetic Resonance (EPR) measurements show that Li+ impurities are located at two different positions in beryl, one in the crystal lattice and the other in the crystal channel. The position of the Li+ impurity in the lattice is generally assumed to be at the site of a missing Be2+ ion. It is shown that this is not the case, but that the Li+ ion is located in a tetrahedron formed by the oxygens of one side of the Be tetrahedron and the nearest oxygen in the channel ring. This Li site has the coordinates (0.423, 0.344, 0.167) and can only be occupied when the neighbouring Be site is empty. There are four such sites around every Be tetrahedron at the distance of 1.46 Å from the Be site. The distance from the Li site to the oxygens of the Li tetrahedron is 1.84 Å. This compares favourably with the much smaller distance of 1.65 Å in the Be tetrahedron. Protons in beryl are trapped at or near these Li sites. Na+ is known to be located at the 2b position at the center of the silicate rings, where it is stabilized by one water molecule located at each of the two surrounding 2a sites. This is also the position of Li+ in the beryl channel. It is found that the presence of Na+ in the ring of six oxygens reduces the radius of this ring. The Na+ impurity has also been supposed to be located at position 2a alone and at 2b stabilized by only one water molecule. It is now proposed that Na+ and H2O are located together in the Al–Be plane when only one water molecule is associated with Na+. The water oxygen is located at or near 2a and Na is closer to the Be site in tetrahedral beryl and closer to the Al site in octahedral beryl. It is proposed that the water protons are also located in the Al–Be plane, which would mean that there exists a third type of water in beryl. The origin of protons and OH? ions in beryl is discussed and it is suggested that the plugs in the beryl channels are CO 3 2? ions. Diffusion of OH? ions and natural radiation may have led to the creation of NO3 and the blue colour of Maxixe beryl. 相似文献
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何起祥 《海洋地质与第四纪地质》1997,(3)
沉积地球科学中若干理论概念经过百余年的争论与探索，已经成为建立在地质现象有序性的基础上，以渐进演化和突变事件为指导思想，以活动论作为世界观，以模拟对比作为主要方法手段，以三维空间作为探索方向的成熟的地球科学分支学科。仅以崇敬的心情献上此文，庆祝业治铮教授八十年诞。 相似文献
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Regional variability in dust‐on‐snow processes and impacts in the Upper Colorado River Basin 
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下载免费PDF全文 S. McKenzie Skiles Thomas H. Painter Jayne Belnap Lacey Holland Richard L. Reynolds Harland L. Goldstein John Lin 《水文研究》2015,29(26):5397-5413
Dust deposition onto mountain snow cover in the Upper Colorado River Basin frequently occurs in the spring when wind speeds and dust emission peaks on the nearby Colorado Plateau. Dust loading has increased since the intensive settlement in the western USA in the mid 1880s. The effects of dust‐on‐snow have been well studied at Senator Beck Basin Study Area (SBBSA) in the San Juan Mountains, CO, the first high‐altitude area of contact for predominantly southwesterly winds transporting dust from the southern Colorado Plateau. To capture variability in dust transport from the broader Colorado Plateau and dust deposition across a larger area of the Colorado River water sources, an additional study plot was established in 2009 on Grand Mesa, 150 km to the north of SBBSA in west central, CO. Here, we compare the 4‐year (2010–2013) dust source, deposition, and radiative forcing records at Grand Mesa Study Plot (GMSP) and Swamp Angel Study Plot (SASP), SBBSA's subalpine study plot. The study plots have similar site elevations/environments and differ mainly in the amount of dust deposited and ensuing impacts. At SASP, end of year dust concentrations ranged from 0.83 mg g?1 to 4.80 mg g?1, and daily mean spring dust radiative forcing ranged from 50–65 W m?2, advancing melt by 24–49 days. At GMSP, which received 1.0 mg g?1 less dust per season on average, spring radiative forcings of 32–50 W m?2 advanced melt by 15–30 days. Remote sensing imagery showed that observed dust events were frequently associated with dust emission from the southern Colorado Plateau. Dust from these sources generally passed south of GMSP, and back trajectory footprints modelled for observed dust events were commonly more westerly and northerly for GMSP relative to SASP. These factors suggest that although the southern Colorado Plateau contains important dust sources, dust contributions from other dust sources contribute to dust loading in this region, and likely account for the majority of dust loading at GMSP. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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1INTRODUCTION BARITE(BASO4)ISANEXTREMELYINSOLUBLESALT;THISAROUSESPROBLEMSINPETROLEUMINDUSTRYBECAUSE BASO4ISAPARTICULARLYINTRACTABLESCALINGAGENT.BARITE PRECIPITATIONINTHEWELLBOREENVIRONMENTGENERALLYRE QUIRESMECHANICALREMOVAL,WITHCONSIDERABLEASSOCIAT EDEXPE… 相似文献
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冰雪层中记录气候与环境变化的痕量含碳杂质 总被引：2，自引：0，他引：2
冰雪层是记录全球变化的主要信息载体之一,其中由生源要素碳形成的杂质种类最多。总结了这些含碳杂质记录古气候和古环境变化方面的研究进展,涉及温室气体、低分子可溶性有机酸、人为有机污染物以及孢粉和高碳数有机质。讨论了今后这些研究的重点所在。 相似文献
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L. F. Simanenko 《Russian Journal of Pacific Geology》2007,1(2):144-152
The localization and chemical composition of the galena from the Partizansky base metal-skarn deposit have been studied in the Second Contact ore body and Bol’nichnaya ore lode. The Partizansky deposit was formed during two stages: base metal-skarn and silver-sulfosalt. Much of the galena was deposited with the productive galena-sphalerite assemblage at the first stage. The galena of the productive stage of the Second Contact body shows wide variations in trace element composition. The galena from the root zone of the ore-bodies (the level of ?135 m) is characterized by steady high contents of economically important isomorphic and mechanical admixtures of bismuth and silver. The galena from the middle levels is almost devoid of isomorphic admixtures and occasionally contains fine inclusions of Ag-tetrahedrite. The high silver (and stibium) contents in the galena from the uppermost horizon (the level of +285 m) are mainly related to mineral inclusions of diverse silver minerals of the late silver-bearing assemblage. The galena from the Bol’nichnaya lode over a large depth interval has elevated contents of isomorphic silver and bismuth, with abundant inclusions of native bismuth. 相似文献
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V.L. Tauson S.V. Lipko N.V. Smagunov R.G. Kravtsova K.Yu. Arsent’ev 《Russian Geology and Geophysics》2018,59(12):1718-1732
The interfacial crystal layer of poorly soluble mineral grown under hydrothermal conditions is modified chemically into a surficial nonautonomous phase (SNAP) and, in this capacity, takes part in growth process, doing several important functions. This paper considers some of them related to geochemistry and mineralogy. The new interpretation is given to the following phenomena: (1) selection of components during crystal growth in multiphase associations; (2) stability of multiphase parageneses having a common chemical component; (3) dual character of the distribution coefficients due to different properties of the crystal volume and SNAP; (4) formation of nano- and microinclusions of unusual composition different from the basic mineral phase; (5) spatial ordering of nano- and microparticles during their directed aggregation at the growing crystal face; (6) accumulation of valuable components (primarily noble metals), incompatible in most of mineral matrixes, in the surficial layer; and (7) effect of “hidden” metal content, associated with the presence of noble metals in the SNAP or of nano- and microinclusions formed during the SNAP evolution. 相似文献