醇解条件下高岭石-硅烷插层复合物的制备与表征

以张家口高岭石为原料,通过二甲基亚砜和甲醇处理获得高岭石-甲醇插层复合物,以此为前驱体,常温条件下在γ-氨丙基三乙氧基硅烷(APTES)及APTES与甲醇组成的反应液中制备出了一系列高岭石-硅烷插层复合物,并利用XRD、FTIR、TEM对其结构和形貌进行了表征。结果表明:反应液中甲醇的加入会使插层复合物的层间距减小,且反应液中甲醇所占的比重越大,所得插层复合物的层间距越小。透射电子显微镜发现:当反应液中不加入甲醇时,所得插层复合物(K-APTES)仍呈现出六方片状的晶形,但加入甲醇后,所得插层复合物出现明显的卷曲剥离现象。上述现象均是由于甲醇与APTES发生醇解反应生成γ-氨丙基三甲氧基硅烷(APTMS)并随APTES分子一起插入高岭石层间造成的。     

微波辐射制备高岭石/聚丙烯酰胺插层复合物

本文将微波技术引入到制备高岭石/有机物插层复合物的研究中,以DMSO为前驱体,研究了微波辐射对高岭石的有机插层、取代、原位聚合作用.发现微波能加快插层和置换反应,极大地缩短反应时间.微波辐射下插层时间为30 min时,插层率即可达到75%以上,置换反应50 min,置换率达到77%以上.同时发现微波在反应中对高岭石具有剥片效果.采用X射线衍射、FT-IR光谱、TG、TEM等技术对插层复合物及微波作用机理进行了探讨.     

高岭石/醋酸钾插层复合物的制备及其影响因素

利用浸泡法制备了高岭石/醋酸钾插层复合物,进行X射线衍射分析,探讨了影响插层的因素。结果表明,醋酸钾对高岭石的插层作用与高岭石的结晶度、插层剂浓度、pH值密切相关。高岭石结晶度越高,越有利于插层作用的进行;高浓度的插层剂(≥30%)可以在较短的时间(12 h)内完成插层作用,而低浓度的插层溶液则需要非常长的时间(≥144 h)才能完成,且获得的插层率较低;pH=10的弱碱性条件最有利于插层的进行;温度对高岭石的插层作用影响不大,在室温就可获得较好的插层效果。     

大同粗晶高岭石-二甲基亚砜插层复合物的制备及表征

首先研究了大同高岭石的矿物学特征,结果表明大同高岭石晶粒粗大,主要由高岭石组成,样品的有序度高,Hinckley指数为1.12。在此基础上,用二甲基亚砜对大同高岭石进行插层,采用XRD、IR和TG-DSC研究插层复合物的结构。XRD结果表明DMSO已插入高岭石层间,d001由原来的0.717nm增至1.13nm,插层率达96.01%;红外光谱证明DMSO中的S=O基团与高岭石的外羟基发生了化学键合作用;热分析结果显示插层复合物于120℃~240℃发生DMSO的脱嵌作用,高岭石的脱羟基温度在400℃~750℃。     

高岭石有机插层复合物的研究现状及发展趋势

综述了高岭石-有机物插层复合物发展历程,分析了高岭石插层复合物制备方法、插层反应影响因素及插层应用,并阐述了有机插层复合物的研究重点及发展趋势。     

高岭石-聚丙烯酰胺插层原位合成Sialon粉体

以高岭石聚丙烯酰胺插层复合物为前驱体,采用原位碳热还原、氮化反应技术,在1400（合成了Sialon粉体。并运用XRD,FT-IR,TEM等技术对合成产物的组成、结构及形貌特征进行研究发现：以插层复合物为前驱体的合成反应,β＇-Sialon,O’-Sialon为主晶相,不舍方石英;而以高岭石-碳混合物为原料的合成产物中,相组成复杂,β＇-Sialon含量较低,并有氧化物。高岭石插层复合物原位碳热还原、氮化反应是合成β＇-Sialon的一种新颖而有效的方法．插层复合物有序的纳米级层状结构特征是提高碳热还原、氮化反应效率的主要原因。     

γ-氨丙基三乙氧基硅烷(APTES)与高岭石层间表面羟基的嫁接反应机理

采用γ-氨丙基三乙氧基硅烷(APTES)对不同有序度高岭石的层间表面羟基进行嫁接反应。应用XRD、FTIR、热分析、元素分析等表征手段对产物进行分析。结果表明:高岭石经过二甲基亚砜(DMSO)预插层后,可与APTES反应得到嫁接产物。在相同反应温度下,由于不同有序度高岭石中的DMSO插层分子脱嵌速率不同,导致嫁接产物在嫁接程度上具有明显差异:有序度高,其嫁接程度高;反之,则嫁接程度低。     

煤系高岭石的原始晶粒尺寸及结晶度对插层作用的影响

采用SEM、XRF、XRD和IR研究了大同、平朔和淮北煤系高岭石的结构、粒度及其特性,探讨了粒度大小对高岭石插层作用的影响及其机理。研究发现:粒度中等且结晶有序的平朔煤系高岭石插层率最高,其次为晶体粗大但结晶有序的大同高岭石,粒度最小且结晶无序的淮北高岭石插层率最低。研究认为高岭石原始晶粒粒度对高岭石插层作用有重要影响,中等粒度最有利于高岭石插层作用的进行,粒度过大或过小均不利于高岭石插层作用的进行,其原因是由于不同粒度的高岭石插层作用过程中导致的差异弹性变形引起的。结晶有序度对高岭石插层作用也有重要影响,结构无序不利于插层作用的进行。     

二甲基甲酰胺对高岭石插层的分子动力学模拟

通过对高岭石-二甲基甲酰胺插层复合物随层间域中二甲基甲酰胺分子数逐渐增加的分子动力学模拟,发现高岭石层间距可被小分子的插层大幅度扩增,但需要借助外界条件克服插层能垒。通过对层间距为1.26 nm模型的界面结构和界面作用的计算,发现二甲基甲酰胺在高岭石层间域中呈单层分布。二甲基甲酰胺的分子平面斜交于层间域表面60°左右,其HC=O官能团的O原子作为质子受体与层间域铝氧面的羟基形成较强的氢键,而甲基则与硅氧面以疏水作用相结合。由于高岭石层间域的铝氧面具有反应活性较高的表面羟基,相比于硅氧面表现出对二甲基甲酰胺更强的亲和性。     

煤系高岭石/醋酸钾插层复合物热相变研究

高岭石插层复合物作为新型矿物材料现已被广泛应用。然而,插层复合物热稳定性较难控制使其在聚合物中的应用一直受到限制。本文应用热分析、X射线衍射、质谱及发射红外光谱等表征技术对煤系高岭石/醋酸钾插层复合物受热分解产物及微结构变化进行了研究。结果表明,煤系高岭石/醋酸钾插层复合物热相变主要经历以下几个阶段:插层水脱嵌(约350℃),插层剂醋酸钾脱嵌(约400℃),脱羟基(约450℃),偏高岭石形成(450~550℃),KHCO3出现(约600℃),KHCO3热分解形成K2CO3和KAl Si O4出现(约700℃),热解产品K2Al2Si O4出现(约800℃),K4Al2Si2O3出现(900~1000℃),大量K3Al O3形成阶段(1100℃及以上)。此外,还发现通过控制插层率和加热温度,可实现高岭石插层复合物的可控分解、新物相合成与转变,从而有利于新材料的合成。     

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.     

Définition d'une limite multicritère ; stratigraphie du passage Campanien–Maastrichtien du site géologique de Tercis (Landes,SW France)Definition of a multi-criteria boundary; stratigraphy of the Campanian–Maastrichtian interval of the geological site at Tercis (Landes,SW France)

Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.     

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).     

NONMETALS DEPOSITS

正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.)     

MATHEMATICAL GEOLOGY

正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology,     

PROSPECTING EXPLORATION

正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.)     

STRUCTURAL GEOLOGY

正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se-     

STRUCTURAL GEOLOGY

正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with