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Pore structure characteristics of the relative water-resisting layer on the top of the Ordovician in Longgu Coal Mine 被引量:3
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作者 Rong Huren Bai Haibo 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期657-661,共5页
In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture a... In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture and pore structure features of the strata, and identified the main channels which govern the permeability and water-resisting ability of the strata. The permeability of the upper, central and lower strata shows as 2.0504 × 10^-3-2.782762× 10^-3, 4.1092 × 10^-3 -7.3387 × 10^-3 and 2.0891 ×10^-3-3.2705 × 10-3 μm^2, respectively, and porosity of that is 0.6786-0.9197%, 0.3109-0.3951% and 0.9829-1.8655%, respectively. The results indicate that: (I) the main channels of the relative water-resisting layer are the pore throats with a diameter more than 6 μm; (2) the major proportion of pore throats in the vertical flow channel and the permeability first increases and then sharply decreases; (3) the fractures occurring from the top to 20 m in depth of the strata were filled and there occurred almost no fracture under the depth of 40 m; and (4) the ratio of turning point of the main flow channel in the strata on top of Ordovician can be used to confirm the thickness of filled water-resisting lavers. 展开更多
关键词 relative water-resisting layer Filling effect Main channels of seepage Pore structure
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Phase Behavior of BaLn_2Mn_2O_7 (Ln=Rare Earth) with a Layered Perovskite Structure 被引量:1
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作者 NaokiKamegashira JianMeng +3 位作者 TakeshiMikami HirohisaSatoh NoriyoshiKakuta KoujiFujita 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第1期17-21,共5页
Many phases appear in BaLn 2Mn 2O 7 family (Ln=rare earth) belonging to one of the Ruddlesden-Popper type compounds, depending upon the experimental conditions such as heating conditions when prepared and compositi... Many phases appear in BaLn 2Mn 2O 7 family (Ln=rare earth) belonging to one of the Ruddlesden-Popper type compounds, depending upon the experimental conditions such as heating conditions when prepared and composition. Some of these phases were characterized by powder X-ray diffraction method using Rietveld analysis. These phases have only a little difference in crystal structure which has fundamentally K 2NiF 4 type structure, although the X-ray diffraction patterns are clearly different: a little deformation or tilting of the oxygen octahedron surrounding a central manganese ion composing the main frame of this structure induce these different diffraction patterns. Phase behavior of these compounds, mainly the detailed relation between various phases in BaTb 2Mn 2O 7, was refined including the data of high temperature X-ray diffractometry. 展开更多
关键词 crystal structure phase relation barium rare earth manganese oxide rare earths
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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 granular computing algebraic quotient space model quotient structure upper(lower) congruence relation
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Metric-Based Resolvability of Quartz Structure
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作者 Muhammad Imran Ali Ahmad +1 位作者 Muhammad Azeem Kashif Elahi 《Computers, Materials & Continua》 SCIE EI 2022年第4期2053-2071,共19页
Silica has three major varieties of crystalline. Quartz is the main andabundant ingredient in the crust of our earth. While other varieties are formedby the heating of quartz. Silica quartz is a rich chemical structur... Silica has three major varieties of crystalline. Quartz is the main andabundant ingredient in the crust of our earth. While other varieties are formedby the heating of quartz. Silica quartz is a rich chemical structure containingenormous properties. Any chemical network or structure can be transformedinto a graph, where atoms become vertices and the bonds are converted toedges, between vertices. This makes a complex network easy to visualize towork on it. There are many concepts to work on chemical structures in termsof graph theory but the resolvability parameters of a graph are quite advanceand applicable topic. Resolvability parameters of a graph is a way to getting agraph into unique form, like each vertex or edge has a unique identification bymeans of some selected vertices, which depends on the distance of vertices andits pattern in a particular graph. We have dealt some resolvability parametersof SiO2 quartz. We computed the resolving set for quartz structure and itsvariants, wherein we proved that all the variants of resolvability parameters ofquartz structures are constant and do not depend on the order of the graph. 展开更多
关键词 QUARTZ polycyclic aromatic hydrocarbon related structure metric dimension metric or distance-based resolvability parameters
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P-wave tomography and relation between shallow and deep structures beneath the Songliao basin
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作者 Qiyan Yang Qingju Wu +2 位作者 Xiaojun Ma Fengxue Zhang Yanrui Sheng 《Earthquake Science》 CSCD 2015年第4期253-261,共9页
We selected relative travel-time residuals from teleseismic waveform data using the waveform correction method and imaged the P wave velocity structure beneath Northeast China. In combination with other geophysical da... We selected relative travel-time residuals from teleseismic waveform data using the waveform correction method and imaged the P wave velocity structure beneath Northeast China. In combination with other geophysical data, we discussed the relation between the shallow and deep structures of the area. The results show that there is a primary high-velocity zone with some high- and low-ve- locity distribution characters beneath the Songliao basin. The low-velocity anomalies may extend down to the upper mantle, and may be the result of material upwelling. The low-velocity anomaly beneath the southern part of the Songliao basin is connected to those beneath the Chang- baishan and A'ershan volcanic areas. It may be an upwelling channel from the mantle beneath the Songliao basin and adjacent area. This finding indicates the Songliao basin was a result of asthenospheric upwelling caused by subduction of the Pacific plate under the Eurasian plate. 展开更多
关键词 Tomography Northeast China Ray Relation between shallow-deep structures
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New Factor to Characterize Mechanism of “Strong Column-Weak Beam” of RC Frame Structures 被引量:1
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作者 李心霞 公茂盛 +1 位作者 韩庆华 谢礼立 《Transactions of Tianjin University》 EI CAS 2015年第6期484-491,共8页
Most reinforced concrete(RC)frame structures did not achieve the "strong column-weak beam" failure mode in recent big earthquakes, resulting in a large number of casualties and significant property loss. To ... Most reinforced concrete(RC)frame structures did not achieve the "strong column-weak beam" failure mode in recent big earthquakes, resulting in a large number of casualties and significant property loss. To deal with this serious problem, a new column-beam relative factor was proposed to characterize the relative yield situation of column ends and beam ends. By limiting the column-beam relative factor, RC frame structures could achieve the "strong column-weak beam" failure mode under the excitation of strong ground motions. The limit values of column-beam relative factor were calculated, analyzed and verified by using structural simulation models for corner columns in the bottom story of structures, which are destroyed most seriously in earthquakes. The results show that the limit values should be analyzed under bi-directional ground motion and with different axial compression ratios of columns. The peak ground acceleration(PGA)of ground motions has no significant effect on the limit values, while the type of strong ground motions has a significant effect on the limit values. 展开更多
关键词 RC frame structure strong column-weak beam limit value of column-beam relative factor moment magnification factor at column end
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Cross-sectional Anatomy and Clinical Meanings of the Extraocular Muscles and Related Structures in Orbit
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作者 Jin-Ping LIU~1 Yun-Sheng LI~1 Kan-Xing ZHAO~(2Δ) Heng SHAO~1 Xue-Han QIAN~2 Jian-Sheng ZHI~11(Department of Anatomy, Tianjin Medical University, Tianjin 300070, China)2(Tianjin Eye Hospital, Tianjin 300040, China) 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期37-38,共2页
关键词 Cross-sectional Anatomy and Clinical Meanings of the Extraocular Muscles and Related structures in Orbit
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The crystal structure of pearls and related shellfish's shells
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作者 Chen Junhao and Chen Guiqing Solid Research Group of Jinan University, Guangzhou, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第1期145-157,共13页
In this article we explored the crystal structure of a few pearls and shellfish's shell of fresh water and sea water, and found that pearls and nacreous layer (perhaps and prismatic layer) of shells are all the sa... In this article we explored the crystal structure of a few pearls and shellfish's shell of fresh water and sea water, and found that pearls and nacreous layer (perhaps and prismatic layer) of shells are all the same: CaCO3, orthorhombic system, aragonite structure and the value of lattice spacings are almost identical. This shows that the pearls of fresh water and sea water are all the same in nature. 展开更多
关键词 CARD The crystal structure of pearls and related shellfish’s shells
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Five-fold local symmetry in metallic liquids and glasses 被引量:1
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作者 M Z Li H L Peng +3 位作者 Y C Hu F X Li H P Zhang W H Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期10-19,共10页
The structure of metallic glasses has been a long-standing mystery. Owing to the disordered nature of atomic structures in metallic glasses, it is a great challenge to find a simple structural description, such as per... The structure of metallic glasses has been a long-standing mystery. Owing to the disordered nature of atomic structures in metallic glasses, it is a great challenge to find a simple structural description, such as periodicity for crystals, for establishing the structure–property relationship in amorphous materials. In this paper, we briefly review the recent developments of the five-fold local symmetry in metallic liquids and glasses and the understanding of the structure–property relationship based on this parameter. Experimental evidence demonstrates that five-fold local symmetry is found to be general in metallic liquids and glasses. Comprehensive molecular dynamics simulations show that the temperature evolution of five-fold local symmetry reflects the structural evolution in glass transition in cooling process, and the structure–property relationship such as relaxation dynamics, dynamic crossover phenomena, glass transition, and mechanical deformation in metallic liquids and glasses can be well understood base on the simple and general structure parameter of five-fold local symmetry. 展开更多
关键词 metallic glass structure–property relation five-fold local symmetry
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System failure analysis based on DEMATEL–ISM and FMECA 被引量:2
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作者 申桂香 孙曙光 +3 位作者 张英芝 王志琼 陈炳锟 马闯 《Journal of Central South University》 SCIE EI CAS 2014年第12期4518-4525,共8页
A new method of system failure analysis was proposed. First, considering the relationships between the failure subsystems,the decision making trial and evaluation laboratory(DEMATEL) method was used to calculate the d... A new method of system failure analysis was proposed. First, considering the relationships between the failure subsystems,the decision making trial and evaluation laboratory(DEMATEL) method was used to calculate the degree of correlation between the failure subsystems, analyze the combined effect of related failures, and obtain the degree of correlation by using the directed graph and matrix operations. Then, the interpretative structural modeling(ISM) method was combined to intuitively show the logical relationship of many failure subsystems and their influences on each other by using multilevel hierarchical structure model and obtaining the critical subsystems. Finally, failure mode effects and criticality analysis(FMECA) was used to perform a qualitative hazard analysis of critical subsystems, determine the critical failure mode, and clarify the direction of reliability improvement.Through an example, the result demonstrates that the proposed method can be efficiently applied to system failure analysis problems. 展开更多
关键词 system failure analysis related failure decision making and evaluation laboratory-interpretative structural modeling(DEMATEL-ISM) failure mode effects and criticality analysis(FMECA)
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Dyke Swarms Florianópolis: Petrologic and Structural Aspects Related to Rifting Supercontinent Gondwana and Formation South Atlantic in the Santa Catarina of Island, Brazil
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作者 Edison R.Tomazzoli Jean de B.Veronez 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期94-96,共3页
From a point of magmatic view,the rupturing Gondwana Supercontinent is registered on the South American shelf in continental flood basalts,mafic dyke swarms,basins rift and,to a lesser extent,by intrusions alkaline.Am... From a point of magmatic view,the rupturing Gondwana Supercontinent is registered on the South American shelf in continental flood basalts,mafic dyke swarms,basins rift and,to a lesser extent,by intrusions alkaline.Among those 展开更多
关键词 polis Petrologic and Structural Aspects Related to Rifting Supercontinent Gondwana and Formation South Atlantic in the Santa Catarina of Island Brazil Dyke Swarms Florian
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In Silico Investigation of Agonist Activity of a Structurally Diverse Set of Drugs to hPXR Using HM-BSM and HM-PNN
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作者 张一鸣 常美佳 +1 位作者 杨旭曙 韩晓 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2016年第3期463-468,共6页
The human pregnane X receptor(hPXR) plays a critical role in the metabolism, transport and clearance of xenobiotics in the liver and intestine. The hPXR can be activated by a structurally diverse of drugs to initiat... The human pregnane X receptor(hPXR) plays a critical role in the metabolism, transport and clearance of xenobiotics in the liver and intestine. The hPXR can be activated by a structurally diverse of drugs to initiate clinically relevant drug-drug interactions. In this article, in silico investigation was performed on a structurally diverse set of drugs to identify critical structural features greatly related to their agonist activity towards h PXR. Heuristic method(HM)-Best Subset Modeling(BSM) and HM-Polynomial Neural Networks(PNN) were utilized to develop the linear and non-linear quantitative structure-activity relationship models. The applicability domain(AD) of the models was assessed by Williams plot. Statistically reliable models with good predictive power and explain were achieved(for HM-BSM, r^2=0.881, q^2_(LOO)=0.797, q^2_(EXT)=0.674; for HM-PNN, r^2=0.882, q^2_(LOO)=0.856, q^2_(EXT)=0.655). The developed models indicated that molecular aromatic and electric property, molecular weight and complexity may govern agonist activity of a structurally diverse set of drugs to h PXR. 展开更多
关键词 human pregnane X receptor agonist activity heuristic method-Best Subset Modeling heu ristic method-Polynomial Neural Networks structural features quantitative structure-activity relation ship
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Gravity observation at continental borderlands (Russia, Primorie, Cape Shults)
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作者 Vladimir Yu. Timofeev Eugenii N. Kalish +7 位作者 Dmitriy G. Ardyukov Maksim G. Valitov Anton V. Timofeev Yurii F. Stus Ruslan G. Kulinich Dmitrii A. Nosov Igor S. Sizikov Bernard Ducarme 《Geodesy and Geodynamics》 2017年第3期193-200,共8页
The paper is focused on different kinds of gravity results obtained in Shults Cape Observatory for 2010 -2015. Gravity observation is interpreted together with GPS observation data which was obtained from 2012 to 2015... The paper is focused on different kinds of gravity results obtained in Shults Cape Observatory for 2010 -2015. Gravity observation is interpreted together with GPS observation data which was obtained from 2012 to 2015 at the same station, The station is situated on Gamov peninsular (42.58° N, 131.15° E, Russia) at the coast of Japan Sea, This region constitutes the eastern boundary of Eurasia. This major continental tectonic feature is associated with a seismic activity, high heat flow and anomalous thickness of earth's crust. The goal of the observation was the investigation of gravity variation with time and seismicity situation monitoring. Gravity observation was developed at special basement by absolute gravimeter (GABL type) and by spring gravimeter (SCINREX CG-5and gPhone type). Tidal models were tested by results of observation with spring gravimeters. Reduction task was solved, as the experimental data received from different points of Shults Cape Observatory was used. Applied reduction coefficient is 203.3 12Gal m l, and agrees with theoretical calculation. Next goal was studying structure of earth's crust by means of gravity models. Gravity anomaly varied from 30 mGal to 46 mGal, which also depend on difference reference system, Experimental results were used for testing of the structure of continental boundary, which also depends on the sea bottom flexion. Thickness of elastic layer was estimated from 12 km to 18 km by using different models. 展开更多
关键词 Absolute and relative gravity observation Space geodesy Reduction task for gravity structure models Crust
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The Structure of Employment and Internal Relations between Employees in Chinese Enterprises in a Developing Market Economy
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作者 冯同庆 许晓军 《Social Sciences in China》 1995年第1期40-49,222,共11页
关键词 The structure of Employment and Internal Relations between Employees in Chinese Enterprises in a Developing Market Economy
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