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1.
化学气相沉积(CVD)合成碳纳米管时,催化剂具有重要的作用。实验证实,一些天然矿物也是潜在的催化剂材料,能在高温下裂解乙炔合成碳纳米管。吸附性能良好的坡缕石和海泡石是优异的催化剂载体,负载钴制备碳纳米管的直径均匀细小;钛酸脂改性后的坡缕石能释放金属铁,并催化碳纳米管的生长;由于矿物晶格中含有催化剂金属离子,大洋锰结核是天然的催化剂。采用矿物催化剂,成本低廉,能够获得碳纳米管与矿物的复合材料,拓宽矿物的应用领域。  相似文献   

2.
以焦化苯(工业级)为碳源,二茂铁(工业级)为催化剂前驱体,氢气为载气,含硫化合物噻吩为生长促进剂,采用浮游催化热分解法制备碳纳米管,通过TEM对产物形貌进行观察和表征,着重讨论噻吩含量、反应温度、苯的挥发温度、催化剂分解温度等实验参数对碳纳米管的制备及其形貌的影响,并对其影响机理进行了分析。结果表明:只要控制好实验参数,工业级原料完全可以制备出碳纳米管,主要工艺参数为噻吩/苯体积比为0.55/100,二茂铁的分解温度为150℃,苯的挥发温度为50℃,反应温度为1170℃。  相似文献   

3.
坡缕缟石对核废料的吸附特性及应用前景   总被引:4,自引:0,他引:4  
曾明果 《贵州地质》1996,13(1):90-92
中国云贵的晚二叠世玄武岩分布地区,发现了成百处坡缕缟石产出点。它可将10000×10-6的放射性溶质吸附清除,为各种性质的核废液的净化、固化及永久安全存放,展示了有经济价值的应用前景。坡缕缟石有独特的矿物结构;广泛的g-OH键、Si-OH-(Si)断键及配位水等,造成其在水油两相中,均可形成任意浓度的非牛顿流体网络结构,此种悬浮液有异常强的耐盐性和高热稳定性,可将核电站等废液中高量的Co50、Cs137、Cs139、Pu239及B ̄3+等离子(团)吸附、共价键结合或网络结构捕获,展示了解决人类环境难题的前景。  相似文献   

4.
利用交互正交试验设计对柠檬酸络合法制备Mn/Ce复合氧化物催化剂(简称Mn/Ce催化剂)的制备条件进行了优化,重点考察金属配比(Mn∶Ce=7∶3、1∶1、3∶7)、焙烧温度(350℃、500℃、650℃)、焙烧时间(2 h、3.5 h5、h)等3种因素对催化湿式氧化(CWAO)降解正丁酸过程中Mn/Ce催化剂活性的影响。结果表明,金属配比和焙烧温度对催化剂活性有显著影响(置信度p分别为99%和95%),焙烧时间对催化剂活性无显著影响(p=90%),焙烧温度与金属配比之间有显著的交互作用(p=99%),得到的最佳制备条件为:Mn∶Ce=3∶7、焙烧温度500℃和焙烧时间5 h;并对最佳制备条件下得到的Mn/Ce催化剂进行XRD、BET和SEM等表征。  相似文献   

5.
以钠化累托石为原料进行改性制备羟基锆交联累托石,并探讨以羟基锆交联累托石制备吸附有机废水的最佳条件。试验得到的最佳条件为:交联剂浓度为0.20mol/L,85℃下回流12h,累托石悬浮液浓度为60,投料比为4mmol/g时,在65℃下交联反应2.5h。在此条件下制备的羟基锆交联累托石的比表面积为9.250m^2/g,对COD的吸附容量可达119mg/L。  相似文献   

6.
贵州西部坡缕石产出特征的研究   总被引:1,自引:0,他引:1  
坡缕石又称坡缕缟石,取名于苏联乌拉尔的坡缕高斯克(Tsavtchenkov 1862),是海泡石族属于富镁的纤维状硅酸盐粘土矿物的一种,其理想分子式为:(Mg_5)[Si_8]O_(20)(OH)_2(OH_2)_4·4H_2O。 该矿产出形式有沉积型;热液型;裂隙—表生型及残积—表生型。前者产出的坡缕石往往与海泡石一起,沉积形成较大的具工业意义的矿床,有人将此种成因的结晶细小或成土壤的坡缕石称之为凹凸棒石;后三者产出的坡缕石为纤维状及树皮状矿物集合体呈脉状及团块状,分布范围不大,工业价值较小。  相似文献   

7.
根据内电解-催化氧化法的应用特点,选用颗粒活性炭作为催化剂的载体,采用浸渍法制备催化剂,并通过用不同催化剂对糖蜜酒精废液COD去除率的比较,确定最佳的催化剂制备条件:Cu(NO3)2浓度为7.5%,浸渍12h,260℃~300℃焙烧活化10~14h;多次使用后的Cu-AC催化剂由催化剂再生技术再生,并应用于糖蜜酒精废液处理。  相似文献   

8.
伊毛缟石在我国的首次发现及其分析电子显微术研究   总被引:1,自引:0,他引:1  
伊毛缟石是一种具有纤维状形态的类晶质水化铝硅酸盐矿物。本文对我国首次发现于福建郭山风化型高岭土矿床中的伊毛缟石用分析电子显微术进行了矿物学研究。研究结果表明,在透射电镜下,伊毛缟石呈长数μm,宽60—250的似线状或纤维状,这是它最重要的矿物学特征之一。选区电子衍射分析给出d_(42)=3.30、d_(04)=2.10和d_(06)=1.40三个比较(氵弥)散的衍射环所表征的典型伊毛缟石衍射花样。其化学成分主要由SiO_2、Al_2O_3和H_2O组成。  相似文献   

9.
在1300℃下将赤泥和石英砂熔制成基础玻璃,经粉磨、筛选后,通过二次热处理工艺获得了以钙铝榴石为主晶相的微晶玻璃。采用XRD和SEM等研究赤泥和微晶玻璃后表明,赤泥主要由方解石和霰石等钙质成分组成;热处理温度对微晶玻璃性能和钙铝榴石晶体结构的影响较大。优化的制备条件为:核化900℃,1h,晶化1105℃,2h,该条件下所得的微晶玻璃晶相含量较高,晶体发育完整,性能良好,相应的体积密度为2.79g/cm3,显微硬度为6.52。  相似文献   

10.
采用Mn/RE多相催化电解氧化方法深度处理垃圾渗滤液,制备了负载型Mn/RE氧化物双活性组分催化剂,研究了Mn/RE负载型催化剂的制备条件(不同组分的浓度配比,焙烧温度,催化剂载体材料)对电多相催化氧化降解垃圾渗滤液中有机物的影响,确定催化剂的适宜制备条件研究结果表明:催化剂中Mn 与稀土组分复合其催化活性好于单一组分,其中以Ce+ Mn制备的催化剂效果最好;浸渍液金属离子质量分数Mn为3%、Ce为1%,焙烧温度为550℃.以γ-Al2O3为载体时所制得的催化剂活性较高并且该催化剂的性能稳定,经6次使用后仍具有一定的催化活性.对于COD为533mg/L的渗滤液生物处理出水的电解氧化降解,采用催化剂后,COD去除率由26.9%提高到71 76%,可有效降低COD.  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.
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.  相似文献   

13.
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   

14.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

16.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

18.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of  相似文献   

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