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INDUCTION—POLYMERIZATION OF PREPARING POLYMERS OF REGULAR STRUCTURE
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作者 Hsiao Lin CHANG, You An Map, Yi Men CHENG Department of Materials Science and Applied Chemistry, National University of Defence Technology, Changsha, 410073 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期821-822,共2页
Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points... Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points and polymerized to polymer of regular structure. Regularity of structure of the polyacrylamide prepared by this means has been verified with electron diffractograms, DSC curve and IR spectrum of the polymer. 展开更多
关键词 TEM INDUCTION POLYMERIZATION OF PREPARING POLYMERS OF regular structure
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Modeling of 3D-structure for regular fragments of low similarity unknown structure proteins
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作者 彭志红 Chen Jie Lin Xiwen Sang Yanchao 《High Technology Letters》 EI CAS 2007年第4期431-435,共5页
Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular ... Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular fragments (α-Helices, β-Strands) of such proteins by the protein secondary structure prediction software, the Basic Local Alignment Search Tool (BLAST) and the side chain construction software SCWRL3. First, the protein secondary structure prediction software is adopted to extract secondary structure fragments from the unknown structure proteins. Then, regular fragments are regulated by BLAST based on comparative modeling, providing main chain configurations. Finally, SCWRL3 is applied to assemble side chains for regular fragments, so that 3D-structure of regular fragments of low similarity unknown structure protein is obtained. Regular fragments of several neurotoxins are used for test. Simulation results show that the prediction errors are less than 0.06nm for regular fragments less than 10 amino acids, implying the simpleness and effectiveness of the proposed method. 展开更多
关键词 low similarity unknown structure regular segment 3D-structure modeling main chain confonnation side chain assembly
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Ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District
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作者 Gong Hongsheng Han Runsheng +2 位作者 Li Ziteng Ren Tao Wang Jiasheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期202-203,共2页
1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is ... 1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is strictly controlled by fault structures.It has developed to one of the famous production bases of lead&zinc and germanium in China. 展开更多
关键词 PB Ore-controlling regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District Zn
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Structure and Pozzolanic Activity of Calcined Coal Gangue during the Process of Mechanical Activation 被引量:7
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作者 郭伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第2期326-329,共4页
On the basis of analyzing coal gangue's chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the c... On the basis of analyzing coal gangue's chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the cement doped coal gangue with various specific surface area was tested. The experimental results indicate that, the lattice structure of metakaolin in coal gangue samples calcined at 700 ℃ disorganizes gradually and becomes disordered, and the lattice structure of α-quartz is distorted slightly. The pozzolanic activity of the coal gangue increases obviously with its structural disorganization. 展开更多
关键词 coal gangue mechanical activation structure NMR tetrahedron
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Crystal Structure and Antitumor Activity of Tri[2- [N-(4'-methyl-benzylsulfonyl)amino]ethyl]-amine 被引量:3
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作者 台夕市 尹显洪 +1 位作者 谭民裕 李一志 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第4期411-414,共4页
The crystal structure of the title compound (C27H38N4O7S3, Mr = 626.79) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pīwith a = 9.411(1), b = 11.645(2), c = 14.672... The crystal structure of the title compound (C27H38N4O7S3, Mr = 626.79) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pīwith a = 9.411(1), b = 11.645(2), c = 14.672(2) , a = 91.80(1), b = 95.36(1), g =104.56(1)o, V = 1547.0 3, Z = 2, Dc = 1.346 g/cm3, l = 0.71073 , m(MoKa) = 0.289 mm-1 and F(000) = 664. The structure was refined to R = 0.0406 and wR = 0.1177 for 4103 observed reflections with I > 2s(I). X-ray diffraction analysis reveals that the title compound is a practically distorted tetrahedron and each molecule contains one lattice H2O by hydrogen bond. The antitumor activity of the title compound against HL-60 human leukemia cells has also been studied by MTT method. 展开更多
关键词 crystal structure distortion tetrahedron antitumor activity
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MPS-FEM Coupled Method for Study of Wave-Structure Interaction 被引量:3
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作者 Guanyu Zhang Xiang Chen Decheng Wan 《Journal of Marine Science and Application》 CSCD 2019年第4期387-399,共13页
Nowadays,an increasing number of ships and marine structures are manufactured and inevitably operated in rough sea.As a result,some phenomena related to the violent fluid-elastic structure interactions(e.g.,hydrodynam... Nowadays,an increasing number of ships and marine structures are manufactured and inevitably operated in rough sea.As a result,some phenomena related to the violent fluid-elastic structure interactions(e.g.,hydrodynamic slamming on marine vessels,tsunami impact on onshore structures,and sloshing in liquid containers)have aroused huge challenges to ocean engineering fields.In this paper,the moving particle semi-implicit(MPS)method and finite element method(FEM)coupled method is proposed for use in numerical investigations of the interaction between a regular wave and a horizontal suspended structure.The fluid domain calculated by the MPS method is dispersed into fluid particles,and the structure domain solved by the FEM method is dispersed into beam elements.The generation of the 2D regular wave is firstly conducted,and convergence verification is performed to determine appropriate particle spacing for the simulation.Next,the regular wave interacting with a rigid structure is initially performed and verified through the comparison with the laboratory experiments.By verification,the MPS-FEM coupled method can be applied to fluid-structure interaction(FSI)problems with waves.On this basis,taking the flexibility of structure into consideration,the elastic dynamic response of the structure subjected to the wave slamming is investigated,including the evolutions of the free surface,the variation of the wave impact pressures,the velocity distribution,and the structural deformation response.By comparison with the rigid case,the effects of the structural flexibility on wave-elastic structure interaction can be obtained. 展开更多
关键词 MPS-FEM coupled method Fluid-structure interaction(FSI) regular wave Wave impact pressure structure deformation response
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Discrete Differential Geometry of <i>n</i>-Simplices and Protein Structure Analysis 被引量:1
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作者 Naoto Morikawa 《Applied Mathematics》 2014年第16期2458-2463,共6页
This paper proposes a novel discrete differential geometry of n-simplices. It was originally developed for protein structure analysis. Unlike previous works, we consider connection between space-filling n-simplices. U... This paper proposes a novel discrete differential geometry of n-simplices. It was originally developed for protein structure analysis. Unlike previous works, we consider connection between space-filling n-simplices. Using cones of an integer lattice, we introduce tangent bundle-like structure on a collection of n-simplices naturally. We have applied the mathematical framework to analysis of protein structures. In this paper, we propose a simple encoding method which translates the conformation of a protein backbone into a 16-valued sequence. 展开更多
关键词 Differential GEOMETRY n-Simplex Discrete MATHEMATICS Protein structure tetrahedron
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A New Kind of Conjugate-nested Central Configurations in Consisted of One Regular Tetrahedron and One Regular Octahedron 被引量:1
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作者 LIU Xue-fei XIANG Yi-hua 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期309-316,共8页
A new case configuration in R^3, the conjugate-nest consisted of one regular tetrahedron and one regular octahedron is discussed. If the configuration is a central configuration, then all masses of outside layer are e... A new case configuration in R^3, the conjugate-nest consisted of one regular tetrahedron and one regular octahedron is discussed. If the configuration is a central configuration, then all masses of outside layer are equivalent, the masses of inside layer are also equivalent. At the same time the following relation between ρ(r =√3/3ρ is the radius ratio of the sizes) and mass ratio τ=~↑m/m must be satisfied τ=~↑m/m=ρ(ρ+3)(3+2ρ+ρ^2)^-3/2+ρ(-ρ+3)(3-2ρ+ρ^2)^-3/2-4.2^-3/2ρ^-2-^-1ρ^-2/2(1+ρ)(3+2ρ+ρ^2)^-3/2+2(ρ-1)(3-2ρ+ρ^2)^-3/2-4(2√2)^-3ρ, and for any mass ratio τ, when mass ratio r is in the open interval (0, 0.03871633950 ... ), there exist three central configuration solutions(the initial configuration conditions who imply hamagraphic solutions) corresponding radius ratios are r1, r2, and r3, two of them in the interval (2.639300779… , +∞) and one is in the interval (0.7379549890…, 1.490942703… ). when mass ratio τ is in the open interval (130.8164950… , +∞), in the same way there have three corresponding radius ratios, two of them in the interval (0, 0.4211584789... ) and one is in the interval (0.7379549890…, 1.490942703…). When mass ratio τ is in the open interval (0.03871633950…, 130.8164950…), there has only one solution r in the interval (0.7379549890…, 1.490942703… ). 展开更多
关键词 N-body problems conjugate-nest consisted of one regular tetrahedron and one regular octahedron central configurations existence and uniqueness
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Inverse Load Identification in Stiffened Plate Structure Based on in situ Strain Measurement 被引量:1
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作者 Yihua Wang Zhenhuan Zhou +2 位作者 Hao Xu Shuai Li Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2021年第2期85-101,共17页
For practical engineering structures,it is usually difficult to measure external load distribution in a direct manner,which makes inverse load identification important.Specifically,load identification is a typical inv... For practical engineering structures,it is usually difficult to measure external load distribution in a direct manner,which makes inverse load identification important.Specifically,load identification is a typical inverse problem,for which the models(e.g.,response matrix)are often ill-posed,resulting in degraded accuracy and impaired noise immunity of load identification.This study aims at identifying external loads in a stiffened plate structure,through comparing the effectiveness of different methods for parameter selection in regulation problems,including the Generalized Cross Validation(GCV)method,the Ordinary Cross Validation method and the truncated singular value decomposition method.With demonstrated high accuracy,the GCV method is used to identify concentrated loads in three different directions(e.g.,vertical,lateral and longitudinal)exerted on a stiffened plate.The results show that the GCV method is able to effectively identify multi-source static loads,with relative errors less than 5%.Moreover,under the situation of swept frequency excitation,when the excitation frequency is near the natural frequency of the structure,the GCV method can achieve much higher accuracy compared with direct inversion.At other excitation frequencies,the average recognition error of the GCV method load identification less than 10%. 展开更多
关键词 structural health monitoring load identification Tikhonov regularization generalized cross validation stiffened plate structure
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Analysis on geological structures influencing gas occurrence at Qidong coalmine 被引量:1
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作者 WU Shi-yong HU Bao-lin YAO Duo-xi ZHANG De-sheng 《Journal of Coal Science & Engineering(China)》 2010年第3期292-295,共4页
The occurrence state of methane is mostly controlled by coalfield geologicalstructures.The coal-bearing strata at Qidong coalmine experienced many tectonic cyclessince their formation.The gas content made by the compl... The occurrence state of methane is mostly controlled by coalfield geologicalstructures.The coal-bearing strata at Qidong coalmine experienced many tectonic cyclessince their formation.The gas content made by the complicated structural geologic systemat the coalfield is very different, which is obviously higher on the north side of the Weimiaofracture belt than that on the south side and near itself.This thesis discussed the gas occurrenceregularity based on the geometric characteristics of the geological structure andits regional tectonic evolution.This study can provide a foundation for coalfield exploitationand deal with coal and gas outburst. 展开更多
关键词 geological structure evolutional regularity gas occurrence Qidong coalmine
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Synthesis and Crystal Structure of a Novel Tetravanadate Modified by Chiral Racemoid Zirconium Complex
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作者 WANG Qing-Wei SHI Lin-Fang +2 位作者 GAO Guang-Gang LI Chuan-Bi EAN Liang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期979-984,共6页
[Zr(phen)4(H2O)4O2(V4O12)](phen)2 1 (phen = 1,10-phenanthroline) was synthesized under hydrothermal condition. The crystal of 1 belongs to triclinic, space group P1^- with a = 10.6334(8), b = 11.9201(8),... [Zr(phen)4(H2O)4O2(V4O12)](phen)2 1 (phen = 1,10-phenanthroline) was synthesized under hydrothermal condition. The crystal of 1 belongs to triclinic, space group P1^- with a = 10.6334(8), b = 11.9201(8), c = 14.6505(10) A, α = 69.9980(10), β = 84.9240(10), γ = 84-1300(10)°, V = 1733.0(2) A^3, Z = 1, Mr = 1672.27, Dc = 1.602 g/cm^3, C72H56N12O18V4Zr, F(000) = 848, μ(MoKa) = 0.747 mm^-1, S = 0.957, R = 0.0504 and wR = 0.1173 for 4011 observed reflections (1 〉 20(I)). The crystal structure of 1 could be discussed in terms of {Zr(phen)2(H2O)2O2}, un-coordinated 1,10-phenanthroline molecules and { V4O12 } unit. In { Zr(phen)2(H2O)2O2 }, the coordination geometry of zirconium is a dodecahedron, but {V4O12} unit is constructed from four apex-sharing {VO4} tetrahedra. Furthermore, {V4O12} links with two {Zr(phen)2(H2O)2O2} units via two bridging oxygen atoms. Interestingly, the two {Zr(phen)2(H2O)2O2} units display D- and L-enantiomers, respectively, upon which the whole molecule represents a racemoid configuration. 展开更多
关键词 crystal structure V-O tetrahedron 1 10-PHENANTHROLINE
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RGBD Salient Object Detection by Structured Low-Rank Matrix Recovery and Laplacian Constraint 被引量:1
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作者 Chang Tang Chunping Hou 《Transactions of Tianjin University》 EI CAS 2017年第2期176-183,共8页
A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the s... A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the sparsity term. Secondly, the depth information is fused into the model by a Laplacian regularization term to ensure that the image regions which share similar depth value will be allocated to similar saliency value. Thirdly, a variation of alternating direction method is proposed to solve the proposed model. Finally, both quantitative and qualitative experimental results on NLPR1000 and NJU400 show the advantage of the proposed RGBD salient object detection model. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Laplace transforms Object recognition RECOVERY
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Numerical Experiment for Dipole-Dipole Interaction in Electro-Magnetism with Help of a Regular Tetrahedron
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作者 Panagis G. Papadopoulos Panos D. Kiousis Christos G. Karayannis 《Open Journal of Physical Chemistry》 2019年第1期13-32,共20页
Aim of this work is to try to explain, on a Rational basis, some equations of Electro-Magnetism, which are based on Experimental data. Any Electric Field can produce a Field of many small Electric Dipoles, continuousl... Aim of this work is to try to explain, on a Rational basis, some equations of Electro-Magnetism, which are based on Experimental data. Any Electric Field can produce a Field of many small Electric Dipoles, continuously distributed in space. In a region, where the Electric Field is constant, in direction and magnitude, all the small Dipoles are parallel to the Electric Field, and are represented by a single, long, parallel to them, fixed in space, Electric Dipole, which is here called Compass. An Alternating current, in a straight Conductor, is studied, by a simple, short computer program, for step-by-step nonlinear dynamic analysis. It is found that, only an Alternating current, not a direct current, can produce an Electric Dipole, in a straight Conductor. The two above Dipoles (Compass-Conductor) are assumed with equal lengths &#8467;, lying on two skew lines, perpendicular to each other, at a distance &#8467;√2, thus forming, by their four ends, a Regular Tetrahedron, with side length &#8467;. Repulsion, between Like Charges, obeys the simple Coulomb Electro-Static law. Whereas Interaction (Attraction or Repulsion), between Unlike Charges, obeys a more accurate Lennard-Jones law. The analysis of Dipole-Dipole (Compass-Conductor) Interaction is performed by hand calculator. The only out-of-balance forces, in the regular Tetrahedron, acting on the Rigid Conductor, are the so-called magnetic forces. Their direction is found, in a simple Rational way, with help of Regular Tetrahedron, without recoursing to a “right-hand-rule”. The proposed model is applied to 1) The force acting on an Electric Charge moving in a magnetic field. 2) The force acting on a Current carrying straight Conductor, due to a magnetic field. 3) The magnetic fields created around a Current carrying straight Conductor. In these applications, proposed model gives reasonable results. Particularly, in third application, results, obtained by proposed model, are found in satisfactory approximation with corresponding ones, obtained by an empirical formula, based on relevant Experimental observations of H.-C. Oersted and A.-M. Ampère. So, the reliability of proposed model is checked. Position and direction of magnetic field vector coincide with those of a corresponding fixed Compass of a constant Electric Field. Main point of present work is that, without introducing the concept of a magnetic field vector, by combining field of dipoles, produced by an electric field, with dipole of an alternating current carrying conductor, the magnetic forces can be determined. 展开更多
关键词 ELECTRIC Field ELECTRIC DIPOLE Compass Conductor Alternating Current Step-by-Step Nonlinear Dynamic Algorithm Dipole-Dipole Interaction regular tetrahedron Coulomb Electro-Static LAW Lennard-Jones LAW MAGNETIC Field Vector MAGNETIC Forces Oersted-Ampère Rule
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The Principle of Square Hole Machining and It's Tooling Structure Design
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作者 Jinxia NIU 《International Journal of Technology Management》 2015年第2期7-8,共2页
In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and pro... In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. 展开更多
关键词 Abstract: In order to meet the rapid needs of processing square hole in mechanical equipment the paper expounds the square hole processing method: planetary wheel method and analyze the principle of tooling structure and process with computer graphics parameters design. The results that as long as the appropriate parameters using the above method not only can punch the square hole can also be processed triangle the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. Keywords: Square hole processing Planet wheel Lelo triangle Square hole drilling
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Data-Path Placement Based on Regularity Extraction and Implementation
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作者 杨长旗 洪先龙 +2 位作者 蔡懿慈 经彤 吴为民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第8期925-936,共12页
An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal ... An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal flow of circuit.Then,it converts the bit slice structure to parallel constraints to enable Q place algorithm.The design flow and the main algorithms are introduced.Finally,the satisfied experimental result of the tool compared with the Cadence placement tool SE is discussed. 展开更多
关键词 Data Path regularity extraction bit slice structure Q place
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Analysis on Structural Control of Coal Distribution in the Northern Qaidam Basin,NW China 被引量:3
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作者 LIU Tianji WANG Tong ZHAN Wenfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期690-696,共7页
The distribution of the Jurassic coal measures in the northern Qaidam Basin is obviously controlled by the regional structures. Based on the existing data of coalfield exploration and combined with the analysis of coa... The distribution of the Jurassic coal measures in the northern Qaidam Basin is obviously controlled by the regional structures. Based on the existing data of coalfield exploration and combined with the analysis of coalfield basement structures, features of the main faults, and the distribution of coal measures, this paper brings forward a scheme of coalfield tectonic divisional units and the definition of the coal-controlling structural styles in the northern Qaidam Basin. The structure control of the distribution of coal measures is further discussed. Several stages of regional tectonic activities since the Indosinian has led to the distribution of coal measures into the characteristics of zonation from the north to south and block from east to west. The results indicate that the structural deformations are the most intense in the front of the three uplifted belts, which are characterized by the combination of thrusts. The coal measures are uplifted to the shallow formations, and are easy to be exploited, but the scale of mines is small because of serious damages by the coal distribution. On the contrary, the stress and strain are weak in the three depressions, with the coal-controlling structural styles being mainly the thrust-fold and thrust-monocline combinations. The distribution of coals in the depressions is relatively stable. The shallower part of the depression will become the key areas for exploration and development of coal resources in the northern Qaidam Basin. 展开更多
关键词 northern Qaidam Basin tectonic units coal-controlling structural styles distribution regularity of coal measures
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Occurrence characteristics and enrichment regularity of indium in pyrite: A case study of Dachang tin ore-field 被引量:2
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作者 Yong-sheng CHENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第8期2197-2208,共12页
To reveal the occurrence state and enrichment regularity of the dispersed element indium in pyrite, the petrology,mineralogy, geochemistry, and mineral physics were researched detailedly. The results suggest that the ... To reveal the occurrence state and enrichment regularity of the dispersed element indium in pyrite, the petrology,mineralogy, geochemistry, and mineral physics were researched detailedly. The results suggest that the structure of pyrite is mainlycomposed of massive structure, disseminated structure, vein structure, reticular structure, comb structure and so on. Generally, thepyrite coexists with sphalerite, marmatite, pyrrhotite, chalcopyrite, galena, and arsenopyrite. And the texture of pyrite primarilyconsists of the metasomatic texture, solid solution texture, idiomorphic?hypidiomorphic granular texture, and disseminated texture.The content of indium in pyrite ranges from 0.491×10?6 to 65.1×10?6 with an average value of 14.38×10?6. Yet, the indium content inthe Gaofeng deposit is higher than that in the Dafulou and Tongkeng deposit, showing a particularly significant supernormalenrichment. Besides, the cadmium content in pyrite is also higher than other dispersed elements, and similarly the abnormalenrichment of cadmium in the Gaofeng deposit is also very significant. An obvious positive correlation exists between In and Cd, orTl, but a negative correlation between In and Re. It is difficult to find out a positive or negative correlation between In and Ga. Theelement zinc is of great importance to the enrichment of indium, which can possibly facilitate to the migration and crystallization of dispersed element indium. 展开更多
关键词 dispersed element indium PYRITE lattice structure enrichment regularity cassiterite-sulfide deposit Dachang ore-field
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Some Properties of a Recursive Procedure for High Dimensional Parameter Estimation in Linear Model with Regularization
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作者 Hong Son Hoang Remy Baraille 《Open Journal of Statistics》 2014年第11期921-932,共12页
Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed t... Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed to overcome the difficulties with high dimension of the observation vector in computation of a statistical regularized estimator. As to deal with high dimension of the vector of unknown parameters, the regularization is introduced by specifying a priori non-negative covariance structure for the vector of estimated parameters. Numerical example with Monte-Carlo simulation for a low-dimensional system as well as the state/parameter estimation in a very high dimensional oceanic model is presented to demonstrate the efficiency of the proposed approach. 展开更多
关键词 Linear Model regularIZATION RECURSIVE Algorithm Non-Negative COVARIANCE structure EIGENVALUE Decomposition
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Structural Connectivity Enhanced Anisotropic 3D Network for Brain Midline Delineation
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作者 Yufan Liu Kongming Liang +6 位作者 Yinuo Jing Shen Wang Zhanyu Ma Yiming Li Yizhou Yu Yizhou Wang Jun Guo 《Journal of Beijing Institute of Technology》 EI CAS 2023年第5期562-578,共17页
Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain m... Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain midline delineation:1)the largely deformed midline is hard to localize if mixed with severe cerebral hemorrhage;2)the predicted midlines of recent methods are not smooth and continuous which violates the structural priority.To overcome these challenges,we propose an anisotropic three dimensional(3D)network with context-aware refinement(A3D-CAR)for brain midline modeling.The proposed network fuses 3D context from different two dimensional(2D)slices through asymmetric context fusion.To exploit the elongated structure of the midline,an anisotropic block is designed to balance the difference between the adjacent pixels in the horizontal and vertical directions.For maintaining the structural priority of a brain midline,we present a novel 3D connectivity regular loss(3D CRL)to penalize the disconnectivity between nearby coordinates.Extensive experiments on the CQ dataset and one in-house dataset show that the proposed method outperforms three state-of-the-art methods on four evaluation metrics without excessive computational burden. 展开更多
关键词 brain midline delineation refinement network structure prior connectivity regular loss
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The Atomic Regular Polyhedron Electronic Shell
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作者 Zilong Kong 《Journal of Modern Physics》 2013年第10期1-19,共19页
The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force struct... The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force structure. A magnetic force regular octahedron is proposed. It is a unique configuration that best satisfies the convergence of electrons moving in the same direction within regular polyhedra. In the case of an electrostatic force crust, the formal electron spin accounts for the crusts intrinsic magnetic moment exceeding the speed of light. If one is to consider that the electron has a magnetic outer layer and an electrostatic inner layer, then the question can be solved and abovementioned inference can provide the basis for magnetic force and momentum for the regular octahedron model. The electron periphery has twenty-petal adsorptive substances;the existence of adsorptive substance causes the magnetic force greater than the electrostatic force. Each electronic shell in the regular polyhedron is in accordance with the electron configuration of periodic table of elements;the kinetic track of each electron is a surface of regular polyhedron. The magnetic properties of iron, cobalt, and nickel can be explained by the regular dodecahedron electronic shell of an atom. The electron orbit converged from reverse direction can explain diamond. The adsorptive substances found in atomic nuclei and electrons are defined as magnetic particles called magnetons. The thermodynamic magneton theory can be better explained when it is analyzed using principles of thermodynamics, superconductivity, viscosity, and even in the creation of glass. The structure of the light is a helical line. 展开更多
关键词 ATOMIC structure regular POLYHEDRON ELECTRONIC SHELL Periodic TABLE of Elements Light Diamond
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