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STUDY ON THE MORPHOLOGY OF LIPS AND ASSOCIATED STRUCTURES IN THE CYPRINID GENUS Parasinilabeo
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作者 张鹗 《Zoological Research》 CAS CSCD 1998年第1期52-58,共7页
The comparative morphology of the lips and associated structures is studied among Parasinilabeo and its taxonomically related groups. On the basis of the morphological features of the lips and associated structure... The comparative morphology of the lips and associated structures is studied among Parasinilabeo and its taxonomically related groups. On the basis of the morphological features of the lips and associated structures, Parasinilabeo is proposed to be closely associated with Pseudogyrinocheilus and Semilabeo ;and four typical mouth patterns are identifled among Parasinilabeo and its taxonomically related groups. 展开更多
关键词 Parasinilabeo Lips and associated structures MORPHOLOGY
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Tectonic Style Associated with the Doleritic Dykes of the Téra-Ayorou Pluton (Liptako, Western Niger)
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作者 Kamayé Tourba Gambo Ranaou Noura +5 位作者 Abdou Dodo Bohari Karimou Dia Hantchi Mallam Mamane Hallarou Hassane Ibrahim Maharou Yacouba Ahmed Moussa Konaté 《International Journal of Geosciences》 CAS 2024年第8期567-581,共15页
The doleritic dykes present in the Téra-Ayorou pluton crosscut the basement of the Nigerien Liptako and are part of the system of intrusive mafic dykes in the Paleoproterozoic domain of the Léo-Man ridge. In... The doleritic dykes present in the Téra-Ayorou pluton crosscut the basement of the Nigerien Liptako and are part of the system of intrusive mafic dykes in the Paleoproterozoic domain of the Léo-Man ridge. In the previous work, emphasis was placed on the petrology, geochemistry and geochronology of the Liptako doleritic dykes. This study aims to analyze the tectonic style of intrusive doleritic dykes in the Téra-Ayorou pluton. The characterization of the deformation which affected the doleritic dykes of the Téra-Ayorou pluton is important for the evaluation of their economic potential. To this end, measurements of tectonic structure planes were taken in the field, and samples were taken from the chilled margin and cores of dolerite dykes, before being processed in the laboratory. Analysis of the tectonic structures collected revealed a brittle tectonic pattern, characterizing a phase of deformation subdivided into two episodes D1 and D2. Episode D1, with its subvertically dipping normal faults and simple N70˚ - N110˚ fractures, is compatible with N-S extension. On the other hand, episode D2, which created shear corridors by reactivation of pre-existing fractures and oriented N150˚ - N170˚, is associated with a WSW-ENE extension. These results open up prospects for the exploration of gold, uranium mineralization and diamonds in the north-west of Niger. 展开更多
关键词 Dolerite Dykes associated structures Deformation Phases North Liptako NIGER
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Structural Imperfections Associated with Supersaturated Vacancies in an HPHT-Grown Diamond Single Crystal 被引量:1
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作者 Longwei YIN, Musen LI, Dongsheng SUN, Zhangying YAO and Jianjun CUI School of Materials Science and Engineering, Shandong University, Jinan 250061, China Zhaoyin HAO StateKey Laboratory for Superhard Materials, Jilin University, Changchun 130012, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第5期553-555,共1页
A diamond single crystal, which was synthesized at a high temperature of 1570 K and a high pressure of 5.5 GPa in a Fe-Ni-C system, was directly and systematically examined by transmission electron microscopy (TEM). I... A diamond single crystal, which was synthesized at a high temperature of 1570 K and a high pressure of 5.5 GPa in a Fe-Ni-C system, was directly and systematically examined by transmission electron microscopy (TEM). It is proposed that there exists a variety of imperfections such as dislocation loops, stacking faults, twins and stacking-fault tetrahedral in the diamond, which may be derived from the supersaturated vacancies generated during rapid cooling from high temperature. The formation process of the imperfections is discussed briefly. 展开更多
关键词 Structural Imperfections associated with Supersaturated Vacancies in an HPHT-Grown Diamond Single Crystal
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Hydraulic metal structure health diagnosis based on data mining technology 被引量:3
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作者 Guang-ming Yang Xiao Feng Kun Yang 《Water Science and Engineering》 EI CAS CSCD 2015年第2期158-163,共6页
In conjunction with association rules for data mining, the connections between testing indices and strong and weak association rules were determined, and new derivative rules were obtained by further reasoning. Associ... In conjunction with association rules for data mining, the connections between testing indices and strong and weak association rules were determined, and new derivative rules were obtained by further reasoning. Association rules were used to analyze correlation and check consistency between indices. This study shows that the judgment obtained by weak association rules or non-association rules is more accurate and more credible than that obtained by strong association rules. When the testing grades of two indices in the weak association rules are inconsistent, the testing grades of indices are more likely to be erroneous, and the mistakes are often caused by human factors. Clustering data mining technology was used to analyze the reliability of a diagnosis, or to perform health diagnosis directly. Analysis showed that the clustering results are related to the indices selected, and that if the indices selected are more significant, the characteristics of clustering results are also more significant, and the analysis or diagnosis is more credible. The indices and diagnosis analysis function produced by this study provide a necessary theoretical foundation and new ideas for the development of hydraulic metal structure health diagnosis technology. 展开更多
关键词 Hydraulic metal structure Health diagnosis Data mining technology Clustering model Association rule
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Galactic kinematics and structure defined by open clusters
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作者 Zi Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2009年第12期1285-1302,共18页
On the basis of recently published astrophysical parameters of the open clusters, we have selected 301 clusters with measurements of their kinematical parameters to trace the local structure and kinematics of the Gala... On the basis of recently published astrophysical parameters of the open clusters, we have selected 301 clusters with measurements of their kinematical parameters to trace the local structure and kinematics of the Galactic disk. The present sample covers a range of over 3.0 kpc from the Sun and gives significant estimates of the disk structure and kinematical parameters of the Galaxy. We derive the disk scale height, vertical displacement of the Sun to the Galactic plane, solar motion with respect to the local standard of rest, circular speed of the Galactic rotation, Galactocentric distance from the Sun, etc. We found that the average scale height of the disk defined by the open clusters is Zh = 58 ± 4pc, with a vertical displacement of the Sun below the Galactic plane of z0 -= - 16±4 pc. Clusters with ages older than 50 Myr are less concentrated in the average plane (Zh=67 ±6pc) than the younger clusters (Zh = 51±5pc). Using the approximation of axisymmetric circular rotation, we have derived the distance to the Galactic center from the Sun R0 = 8.03 ±0.70 kpc, which is in excellent agreement with the best estimate of the Galactocentric distance. From a kinematical analysis, we found an agedependent rotation of the Galaxy. The older clusters exhibit a lower velocity of vorticity, but have the same shear as the younger clusters. The mean rotation velocity of the Galaxy was obtained as 235 ± 10 km s-1. 展开更多
关键词 Galaxy: disk -- Galaxy: kinematics and dynamics -- Galaxy: open clustersand associations: general -- Galaxy: structure
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