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51.
WANG Lijuan LU Anhuai WANG Changqiu LI Xuejun ZHENG Xishen ZHAO Dongjun LIU Rui 《《地质学报》英文版》2006,80(2):180-184
With the TEM and physical gas adsorption techniques, porous properties of nano-ribriform silica （MLD： 92.73%） from natural chrysotile are studied in this paper. The results indicate that porous nano-fibriform silica results from brucite octahedral sheets of nature chrysotile dissolved completely and Si-O tetrahedral sheets collapsed by acid leaching. Its length is at a micron or nanometer scale. There are two types of pores： pores among neighboring fibers and pores in nanoriber. These pores （less than 6.5 nm in diameter, mostly 2.1 nm and 3.8 nm） all belong to mesopores. The pores in fibers consist of those among SiO2 particles, those among aggregates, remnant nanotubes and capillary tubes. Nanoribriform silica proves better than the traditional silica as a carrier of catalyzer and a filler for reinforce rubber and plastics. 相似文献
52.
Journal of Geographical Sciences - National parks are useful entities for looking at coordinated efforts to improve the Tibetan Plateau’s function as an ecological safety barrier and the... 相似文献
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Sojung Park Mansik Choi Dongjun Jang Dongjin Joe Kyunggue Park Hyojin Lee Junsik Woo Taeha Kim Jongkyu Park 《Ocean Science Journal》2020,55(1):69-84
In this study, we investigated the spatial and temporal distribution of heavy metals and nutrients in Gyeonggi Bay, Korea, to determine their present statu 相似文献
55.
通过检测生产性能及血液生化指标和内分泌指标,研究了热应激对肉鸡的影响。结果表明：肉鸡体重、平均日增重、饲料转化率及血清总蛋白、白蛋白、钙、磷、甲状腺激素（Ｔ３、Ｔ４）含量显著下降（Ｐ＜０．０５或Ｐ＜０．０１）,血清钾则仅在３０日龄显著下降,但血清尿素氰、氯、皮质醇含量及血清乳酸脱氢酶、肌酸磷酸激酶活性显著升高（Ｐ＜０．０５或Ｐ＜０．０１）,热应激对血清钠和葡萄糖含量影响不大。 相似文献
56.
四川盆地下侏罗统自流井组发育东岳庙段和大安寨段两套富有机质页岩层系,主要为湖泊相的页岩夹粉砂岩、介壳灰岩。基于页岩、介壳灰岩和粉砂岩之间的组合特征,自流井组共识别出3类7种页岩岩相组合类型。页岩有机质丰度中等,有机质类型以Ⅱ1、Ⅱ2型为主,热演化程度中等,油气共存。页岩储集空间既有无机孔,也有有机质孔,局部发育微裂缝。自流井组页岩中无机矿物与有机质、有机质与有机质孔的配置关系控制着页岩源—储配置的有效性,在较高的演化程度下,随着TOC的增大有机质孔隙度增大,页岩的源—储配置关系变好。刚性矿物稳定支撑格架下保存的固体沥青个体大,内部有机质孔数量多、孔径大;黏土矿物不稳定支撑格架下保存的沥青呈长条形,内部的有机质孔孔径较小。基于页岩层系不同岩性源—储耦合条件评价结果,页岩的源—储耦合条件明显优于夹层,源—储耦合条件好的优质页岩层段是页岩油气的甜点层段,其中黏土质页岩最好,介壳灰质页岩、粉砂质页岩为次;介壳灰岩和粉砂岩夹层不具备烃源条件且储集条件差,只能与相邻的富有机质页岩形成近源聚集体系。 相似文献
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58.
Xu Dongjun 《岩土力学》1989,10(3):13-19
The research achievements about weak intercalated layers of bedding rocks are presented in this paper, which were made by the author and his colleagues in the past 30 years. A lot of work made are related to the stability analyses for slops of large-scale open-pit minings, and for bed rocks of key water conservancy projects. The emphasis of this paper is put on shearing testing method in-situ, and the research results of deformation and strength properties of weak intercalated layers. 相似文献
59.
The rock deformation and failure tests are performed along various stress paths under true triaxial stress state.
The experimental results have shown that the change of three principal stresses (the increase of the maximum principal stress, the decrease of the minimum principal stress, the decrease of the confining pressure and the increase or decrease of the intermediate principal stress ) can lead to deformation and failure in rocks. The strength, the deformability and the failure precursors of rocks are related with stress paths.
Based on the results of the study, the problems of the stress path in rock engineering are discussed. 相似文献