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1.
正多孔黏土异质结构材料(PCHs)是以长链烷基铵为模板剂,以黏土矿物为基体制备的一类柱撑材料。PCHs独特的孔径分布范围弥补了微孔性柱撑黏土矿物和介孔硅之间的孔径分布间隙。其有希望成为良好的吸附剂、催化剂、载体或合成其他多孔材料的模板。因此,PCHs的成孔机制和有效的结构控制尤为重要。长期以来,PCHs的成孔机制一直参照介孔硅的分子  相似文献   

2.
介孔分子筛材料合成及应用研究的现状及进展   总被引:1,自引:0,他引:1  
介孔分子筛材料是近年来引起人们广泛关注的一类新型功能材料,由于其具有孔分布有序且孔径均匀等结构优点而在催化、电磁传感器、纳米光学器件和色谱载体等领域中有潜在的应用价值。本文全面综述了介孔材料材质及机理的研究概况,合成方法,模板剂、助剂对于介孔分子筛材料合成的影响,以及介孔材料的应用研究,并就该类材料在合成和应用领域中存在的问题及研究方向做了简要论述。  相似文献   

3.
钾霞石快速溶胶-凝胶法制备及表征   总被引:1,自引:0,他引:1  
使用氨水调节pH值,正硅酸乙酯-硝酸铝-硝酸钾-乙醇溶胶在5~12min内快速形成凝胶,最佳胶凝条件为:H2O/TEOS=25,EtOH/TEOS=4,pH≈9。干凝胶在862℃晶化热处理3h制备得到纳米级钾霞石粉体。合成钾霞石粉体一次粒子粒径约50nm,团聚后的二次粒子粒径5~20μm,平均孔径11.2nm,孔径呈双峰分布,属于中孔材料,可用作催化剂助剂。  相似文献   

4.
张征 《地质与勘探》2021,57(6):1408-1415
页岩的微观孔隙结构对页岩气的赋存至关重要,气体吸附法可以较好对页岩的微观孔隙结构进行表征。通过测量丁页1井不同深度样品的矿物含量、RO值和TOC含量,结果表明丁页1井龙马溪组页岩样品的矿物含量比较稳定,有机质成熟度变化不大,均为过成熟。通过低温氮吸附法计算样品的比表面积和微、介孔容积和孔径分布,结果表明:(1)样品的平均孔径为2.8 ~ 4.9 nm,10 nm以下的孔隙提供了大部分的微、介孔容积。微、介孔容积为0.00136 ~ 0.0108 cm3/g,平均0.004 cm3/g,比表面积为2.54 ~ 13.69 m2/g,平均6.68 m2/g;(2)微、介孔容积、比表面积和TOC三者之间有很强的正相关性。通过计算TOC含量为0时的微、介孔容积和比表面积推算无机孔和有机孔之间的比例和其对比表面积的影响,发现有机孔提供了大部分的微、介孔容积,有机孔还是比表面积的主要贡献因素;(3)样品的吸附曲线符合IPUAC分类中的第IV型吸附曲线,样品的脱附曲线反映样品孔隙形态随TOC含量的增加,由楔形孔(不定型孔)变为连通的墨水瓶型孔(狭缝型孔)或墨水瓶型孔。  相似文献   

5.
利用低角度X射线衍射、红外光谱、喇曼光谱及孔结构分析,研究了用铁盐水解法制备的铁层柱蒙脱石的结构与性质。所制得的铁层柱蒙脱石以介孔型层离结构为主,微孔型柱撑结构为辅。前者为蒙脱石片层与铁离子水解产生的聚合羟基铁簇合物堆垛而成的卡房状结构,与d值为6.4±1.0nm的X射线衍射宽峰相对应;微孔型柱撑结构则与d值约1.5nm的(001)衍射峰相对应。所合成的系列铁层柱蒙脱石中最大的比表面积和孔容分别为215.7m2/g和0.291mL/g。500℃热处理后,仍保存铁层柱蒙脱石的介孔结构。铁层柱蒙脱石富含阴离子(NO3-),并作为平衡铁水解聚合物正电荷的反离子而稳定存在,可为磷钨酸离子[PW12O40]3-所交换。铁层柱蒙脱石的新型结构和特殊性质在催化剂、载体与吸附剂等领域具新的应用前景。  相似文献   

6.
为了探讨煤的微孔介孔演化特征及其成因,在华北二叠纪煤盆地,采取7个不同煤化程度的煤样,分别采用低压CO2吸附法和液氮吸附法对各煤样的纳米孔隙进行表征;基于密度泛函理论、DA(Dubinin—Astakhov)、DR(Dubinin—Radushkevich)、BET、BJH等方程计算孔隙表面参数;分析煤的微孔(孔径<2 nm)和介孔(孔径2~50 nm)的孔径分布、孔容和比表面积随煤级变化的规律;并探讨微孔形成的主控因素及介孔的形成机制。研究结果表明:微孔孔容和比表面积与煤的镜质体反射率高度正相关,微孔在吸附中占绝对支配性主导地位;微孔孔径分布曲线呈双峰分布,不同煤级煤样的曲线形态相似,极微孔随煤级增加最快;介孔比表面积和孔容随煤级增加逐渐下降,介孔孔径分布呈单峰分布,随着煤级的增加,煤的BET比表面积先减少后增加,呈U形分布;微孔的形成应主要受控于煤的类微晶参数和芳香层片间的堆垛结构,而介孔的形成应主要受控于煤侧链的变化和煤的基本结构单元间隙。  相似文献   

7.
采用不同极性有机溶剂对取自东营凹陷地区泥页岩样品进行了逐次抽提处理,使用小角X射线散射表征技术对处理前后样品进行介孔分布特征表征和分析。结果显示,正己烷溶剂抽提效果较弱,极性较强的氯仿、甲醇/丙酮/氯仿混合溶剂及二氯甲烷/甲醇混合溶剂能够萃取出孔隙中赋存的有机质,二硫化碳/N-甲基吡咯烷酮混合溶剂由于极性太强对孔隙进行改造和破坏。经溶剂抽提后样品主峰位置分布在10 nm左右,最可几孔径值和中值孔径尺度分别介于6.7~14.5 nm和15.9~22.9 nm之间,细介孔体积百分比分布在9.5%~32.3%范围内。在泥页岩生烃阶段,粘土矿物为油气储存提供了有效储集空间,高粘土矿物相对含量的泥页岩对应的介孔分布曲线向更小孔径处集中,细介孔体积百分比与分形维数参数之间均存在明显的正相关关系,可见与粘土矿物有关的孔隙比表面趋向于粗糙化,比表面积趋大,为油气的赋存提供有利的条件。自然演化样品及热模拟样品介孔分布表征揭示了泥页岩从低成熟向高成熟热演化阶段转化的过程中,细介孔体积占介孔总体积百分比呈现出先增大后减小的趋势,而粗介孔与之相反。  相似文献   

8.
本次研究以四川盆地南部(川南地区)上二叠统龙潭组煤系页岩为例,利用场发射扫描电镜(FE-SEM)对页岩孔隙进行定性观察分析,联用高压压汞实验、N2与CO2吸附-脱附实验,以及CH4等温吸附实验开展海陆过渡相煤系页岩全孔径孔隙结构特征的定量表征,并探讨孔隙结构对含气性的影响。海陆过渡相煤系页岩粒间孔、粒内孔和有机质孔等基质孔隙较为发育,微裂缝较少。孔隙形态以平板狭缝状和墨水瓶状为主,具有较好的开放性特征。页岩全孔径孔容分布曲线呈两极化分布,孔径小于30nm和大于5μm的孔隙大量发育。宏孔(>50 nm)、介孔(2~50 nm)和微孔(<2 nm)的孔容贡献率依次降低,分别占42.2%、36.3%和21.4%。页岩孔比表面积分布曲线呈单峰型分布,随着孔径增大,孔比表面积减小,微孔尤其是孔径值小于8 nm的孔隙提供较大的孔比表面积。微孔、介孔和宏孔的孔比表面积贡献率依次降低,分别占72.7%、25.0%和2.3%。龙潭组页岩总含气量为2.61~6.02 m3/t,其中吸附气比例占优势,含量为1...  相似文献   

9.
以粉煤灰为主要原料,以十六烷基三甲基溴化铵(C16TMABr)为模板剂,探索了在碱性条件下水热合成铝硅质介孔分子筛的可行性.  相似文献   

10.
硅灰石与盐酸反应合成高比表面积多孔SiO2 条件为pH值≤ 1.5 ,添加剂为聚乙二醇和NH4Cl,反应后体系中和到pH =4.0 ,经固液分离 ,烘干 ,6 5 0~ 75 0℃灼烧 2h得产物。产物比表面积 479± 45m2 g ,表观密度 0 .34± 0 .0 3g cm3 ,DBP吸着率 173± 16ml 10 0g ,平均中位径D50 为 6 .9± 0 .5um ,孔径分布集中在 1~ 2nm。上述结果得到透射电镜分析证实。  相似文献   

11.
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.  相似文献   

12.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
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.  相似文献   

13.
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).  相似文献   

14.
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  相似文献   

15.
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),  相似文献   

16.
17.
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-  相似文献   

18.
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-  相似文献   

19.
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.)  相似文献   

20.
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  相似文献   

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