含铁绿柱石的改色机制研究

含铁绿柱石经γ射线辐照或特定温度热处理,可因铁价态的改变引起颜色发生相应变化。处理前后的吸收光谱和顺磁共振谱研究表明,辐作用使隧道位的Ｆｅ＾２＋氧化Ｆｅ％３＋,八一位上的Ｆｅ＾３＋还原为Ｆｅ＾２＋,热处理使隧道位及八面体位Ｆｅ＾３＋均还原为Ｆｅ＾２＋。     

蓝宝石的顺磁共振研究

有关蓝宝石的顺磁共振研究已有很多报道。在以往的报道中,大多偏向于蓝宝石中Ｆｅ谱线的价态归属和含量高低等方面的研究。而对其中Ｆｅ３＋置换Ａｌ３＋以后有关Ｆｅ３＋的占位特征、畸变程度、磁学性质等有关顺磁共振谱与结构之间的关系,讨论得很少。本文对山东蓝色蓝...     

山东蓝宝石铁离子的价态及其对色调的影响

山东蓝色蓝宝石的着色是由Ｔｉ４＋离子与Ｆｅ２＋离子合理配比而成，一般控制在Ｔｉ４＋／Ｆｅ２＋＝１的配比范围内。多余的Ｆｅ２＋和其它Ｆｅ３＋离子存在都不利于蓝色蓝宝石正常呈色。通过穆斯堡尔谱和电子顺磁共振谱分析，测定了山东蓝宝石中铁离子的不同价态和浓度。对Ｆｅ２＋和Ｆｅ３＋离子所引起的吸收光谱特征作了研究，查明只有Ｆｅ３＋浓度很高时才产生４７７ｎｍ吸收峰，是致使山东蓝宝石表观上呈深蓝带黑色调的的重要原因。     

硬玉的谱学研究

通过白色硬玉和翠绿色硬玉的红外光谱和电子顺磁共振谱的研究,红外光谱表明白色硬玉和翠绿色硬玉均为纯硬玉,只是翠绿色硬玉中还含有少量白云石;ＥＰＲ谱表明,白色硬玉和翠绿色硬玉均存在顺磁性离子Ｃｒ＾３＋和Ｆｅ＾３＋,且占据「ＡｌＯ３」八面体中Ａｌ６＋的位置而进入晶格,说明悲翠的颜色成因由Ｃｒ＾３＋和Ｆｅ＾３＋离子而产生的。     

粘土矿物酸溶解反应特征

应用界面化学理论与实验方法分析了膨润土在酸性水溶液中的溶解反应特征,进而探讨其反应机理。膨润土在酸性水溶液中的溶解受到矿物表面吸附、离子交换和解吸附等界面化学过程的制约,与溶液中的酸度、反应时间及温度有关。处于粘土结构单元中不同位置的离子溶解趋势不同。探讨了膨润土在不同条件下Ｃａ２＋、Ｍｇ２＋、Ｆｅ３＋、Ａｌ３＋溶出的特征,Ｃａ２＋的溶解是吸附控制过程,Ｍｇ２＋、Ｆｅ３＋、Ａｌ３＋是吸附和反应控制的综合结果。     

Cr~(3+)在蒙脱石中吸附位置研究——基于蒙脱石、CTAB-和NH_4~+-交换层间域的蒙脱石吸附铬研究

蒙脱石具良好的阳离子可交换吸附特性。在提纯蒙脱石的基础上,用氯化铵(NH_4Cl)和十六烷基三甲基溴化铵(CTAB)分别交换蒙脱石层间阳离子制备了改性蒙脱石,并用提纯蒙脱石、改性后的蒙脱石吸附碱式硫酸铬溶液中的铬离子,获得含铬蒙脱石样品。针对上述的含铬蒙脱石进行包括粉末X射线衍射术(XRD)、电子顺磁共振谱术(EPR)和傅里叶变换红外吸收光谱术(FTIR)以及电感耦合与等离子体原子发射光谱(ICP-AES)等测试和分析。吸附残余液的化学分析结果和含铬蒙脱石样品的XRD结果显示CTAB对蒙脱石的层间的封闭是较完全的,层间几乎未发生交换吸附;而NH_4~+—蒙脱石和蒙脱石层间则发生交换吸附。吸附前后样品的红外吸收谱发生了较大变化,表明三个含铬样品的红外吸收谱上出现的硅醇和铝醇向低波数延展的现象是由铬离子吸附在蒙脱石结构片的六方孔中所致。EPR的结果指示甚至在蒙脱石的少量四面体和/(或)八面体位中也有Cr~(3+)占位。     

镍基和钠基蒙脱石的热处理对比研究

研究了钠基蒙脱石吸附Ni^2+后以及产物经过500℃热处理后的结构变化,采用了X射线荧光光谱术(XRF)、粉末X射线衍射术(XRD)、电子顺磁共振谱术(ESR)、傅里叶变换红外吸收光谱术(FTIR)以及拓展X射线吸收精细结构谱术(EXAFS)等分析手段测试了固体产物的特征,并利用电感耦合等离子体原子发射光谱术(ICP-AES)分析了吸附残余液的化学组成。吸附残余液的化学分析结果表明,溶液中Ni^2+的量显著降低,同时又检测到一定量的Na^+、Mg^2+等离子,且XRD结果也证实蒙脱石层间域发生Ni^2+的交换吸附。EXAFS和ESR的结果进一步表明吸附反应后Ni^2+以[Ni(H2O)6]^2+的形式存在于蒙脱石的层间域,样品经过500℃加热后产物的XRD和FTIR结果均显示出现类滑石相产物。     

雪宝顶绿柱石的谱学研究

本文对雪宝顶绿柱石的晶体化学、矿物谱学、热释光和流体包裹体特征等进行了分析讨论。结果表明,雪宝顶绿柱石化学成分具有富碱、富水、过渡金属离子以Ｆｅ＾３＋、Ｆｅ＾２＋为主的特点。碱金属离子,水和Ｆ＾２＋存在于绿柱石结构隧道中,隧道水分为Ⅰ型和Ⅱ型两类,Ⅰ型水可以进一步区分为Ⅰ１和Ⅰ２两亚类,Ｆｅ＾２＋主要与隧道水结合形成水合离子「Ｆｅ＾２＋（Ｈ２Ｏ）」。Ｆｅ＾３＋主要占位于绿柱石ＡｌＯ６八面体中的Ａｌ     

蒙脱石中铁的赋存状态的研究

通过对徐闻、三水、高州等地五个样品的Ｘ射线衍射分析，化学全分析，分析它们为含铁量不同的蒙脱石，层间可交换阳离子主要为Ｃａ＾２＋。几个样品穆斯堡尔谱表明铁主要以Ｆｅ＾３＋的形式存在，含铁量较高的样品ＸＧＡ、ＸＳＡ、ＳＳ的谱可以拟合出Ｆｅ＾３＋的二对四级双峰，表明铁在蒙脱石中占据两种不等同的八面体位置。     

硫化物吸附金属离子的实验研究──Ⅱ．温度与介质条件的影响

合成ＰｂＳ和ＺｎＳ对Ａｇ２＋、Ｃｕ２＋、Ｃｄ２＋、Ｆｅ２＋、Ｍｎ２＋、Ｍｇ２＋、Ｓｂ２＋和Ｂｉ３＋等离子吸附量与温度关系的实验研究表明，其遵从Ｋｅｌｖｉｎ公式：在Ａ类吸附，即抗衡离子交换型吸附中，温度上升，其吸附量升降由反应热决定，本实验中Ａ类吸附多为上升型；而大部分Ｂ和Ｃ类吸附，即朗谬尔型及反朗谬尔型的吸附量则随温度上升呈指数下降。例外的仅有ＰｂＳ对Ｂｉ３＋离子的吸附，其吸附量随温度上升有微弱的上升。这可能与Ｂｉ３＋离子和吸附剂ＰｂＳ之间共晶反应和铅的铋硫盐的形成有关。Ａ类吸附的吸附量受介质条件变化影响很少。但对Ｂ和Ｃ类吸附，吸附量受ｐＨ和离子强度变化影响取决于三个因素：①吸附剂ＰｂＳ、ＺｎＳ表面电荷特性；②溶液介质条件变化时吸附离子在溶液中离子态的分布与变化；③被吸附离子在吸附剂中扩散和形成化合物或共晶的能力。因此，当ｐＨ增加时，Ｐｂｓ和ＺｎＳ对金属离子吸附量的变化表现出多样性：增加的有ＰｂＳ对Ｆｅ２＋离子的吸附；下降的有ＰｂＳ对Ｓｂ３＋离子的吸附和ＺｎＳ对Ｆｅ２＋、Ｍｎ２＋离子的吸附；不变的有ＰｂＳ对Ｂｉ３＋、Ｚｎ２＋离子的吸附和ＺｎＳ对Ｍｇ２＋离子的吸附。当溶液中离子强度增加时，由于溶液中自由态离子     

The terrestrial fauna of the Late Triassic Pant-y-ffynnon Quarry fissures,South Wales,UK and a new species of Clevosaurus (Lepidosauria: Rhynchocephalia)

Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.     

The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts

The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H₂O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H₂O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.     

Quaternary stresses revealed by calcite twinning inversion: insights from observations in the Savonnières underground quarry (eastern France)

Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ₁ roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).     

HYDROGEOLOGY

正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level     

METAMORPHIC PETROLOGY

正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),     

SERIALS

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GEOPHYSICAL EXPLORATION

正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-     

QUATERNARY GEOLOGY & GEOMORPHOLOGY

正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-     

PETROLEUM GEOLOGY

正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)     

GEOCHEMISTRY

正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861