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1.
人造卡邦金刚石研究   总被引:1,自引:0,他引:1       下载免费PDF全文
人造卡邦金刚石是用特种石墨在触媒在77kb(7700MPa)以上压力和1500°K左右温度下合成的。经微观和宏观检测,它具有结构致密、晶粒间以金刚石键相结合的微观特征,与天然卡邦结构相近,它在宏观上表现出显微硬度高(相当于天然单晶)、抗压强度高、耐磨性好、颗粒大、可指定成形等优点及耐热性差的不足。人造卡邦金刚石的研究成功并将它应用于工业、国防和科技各个方面,使当今人造金刚石发展跃上新台阶。  相似文献   

2.
人造金刚石提纯去石墨新工艺的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
通过研究和试验,提出一种经济合理,有效降低污染的人造金刚石提纯去石墨方法-硫酸法。通过近百万克拉人造金刚石提纯表明,本方法完全可以用于工业生产。  相似文献   

3.
人造金刚石合成片中再结晶物质的空间分布   总被引:1,自引:0,他引:1  
通过电子显微镜观察,发现金刚石合成片断面的再结晶物质具有分带现象,金刚石晶体出现了再结晶片-板状石墨亚带和枝状石墨亚带中,这一发现有助于深入探讨金刚石的生长条件和形成机理。  相似文献   

4.
2003年国外人造金刚石获新进展,我们怎么办?   总被引:2,自引:0,他引:2       下载免费PDF全文
刘广志 《探矿工程》2003,30(5):67-68
2003年,国外人造金刚石获得2项突破性进展——俄罗斯生产出性能超过金刚石的大分子三维聚合物,日本研发出超高硬度人造金刚石。为此,提出了改变我国合成金刚石工业停滞不前局面的建议。  相似文献   

5.
通过对人造金刚石进行整形处理,采用适当的工艺,把连聚晶分离成单晶,对不规则的晶体进行浑圆化处理。整形后人造金刚石的连聚晶可控制在5%左右,经分选后可选出一定比例的高品级金刚石,既保证了金刚石质量的稳定性,又创造了较好的经济效益。  相似文献   

6.
文中综述了世界金刚石的生产情况,分析了人造金刚石产量增长的原因,介绍了国外在人造金刚石合成技术、金刚石的提纯、提高金刚石强度的方法,以及钻头用金刚石的粒度和钻头设计等方面的最新进展.  相似文献   

7.
人造金刚石合成片中的特殊产物   总被引:1,自引:0,他引:1  
王安平  姚杰 《世界地质》2000,19(1):95-97
在人造金刚石合成片内,常见矿物为金刚石、再结晶石墨和金属碳化物.此外,在与叶腊石接触的局域空间,发现了新的特殊产物锰铝榴石、锰辉石和锰橄榄石,为人造金刚石用非金属催化剂的合成工艺提供了启示.  相似文献   

8.
胡中立 《地质与勘探》1994,30(4):80-80,F003,52
详细介绍了低温电镀人造金刚石孕镶钻头在“打滑“地层中试用比热压人造金刚石和热压天然金刚石孕镶钻头技术经济效益高的情况,分析了该种钻头时效高、成本低、胎体磨损快,缘于电镀工艺特点和胎体合金成分诸因素,提出了在钻进中防止过快磨损的措施和途径。  相似文献   

9.
提高人造金刚石单晶质量   总被引:1,自引:0,他引:1  
从设备的更新,原材料质量的提高,人造金刚石合成工艺的改进等方面,对如何提高金刚石单晶质量进行了探讨。  相似文献   

10.
研究了金刚石合成过程中不同时期触媒金属金相组织的变化,讨论了人造金刚石的合成过程,给人造金刚石合成机理的研究提供了一些客观依据。最后作者阐述了自己对转化机理的见解。  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.
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   

15.
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   

16.
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   

17.
18.
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   

19.
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   

20.
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   

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