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MINIMAL FOLIATIONS FOR THE HIGH-DIMENSIONAL FRENKEL-KONTOROVA MODEL
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作者 缪雪晴 葛建华 +1 位作者 秦文新 王亚南 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期564-582,共19页
For the high-dimensional Frenkel-Kontorova(FK)model on lattices,we study the existence of minimal foliations by depinning force.We introduce the tilted gradient flow and define the depinning force as the critical valu... For the high-dimensional Frenkel-Kontorova(FK)model on lattices,we study the existence of minimal foliations by depinning force.We introduce the tilted gradient flow and define the depinning force as the critical value of the external force under which the average velocity of the system is zero.Then,the depinning force can be used as the criterion for the existence of minimal foliations for the FK model on a Z^(d)lattice for d>1. 展开更多
关键词 Aubry-Mather theory Frenkel-Kontorova model minimal foliation depinning force gradient flow
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FIAs(Foliation Intersection/Inflection Axes) Preserved in Porphyroblasts,the DNA of Deformation:A Solution to the Puzzle of Deformation and Metamorphism in the Colorado,Rocky Mountains,USA 被引量:3
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作者 SHAH Afroz Ahmad 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第5期971-984,共14页
FIAs have been used extensively for more than a decade to unravel deformation and metamorphic puzzles. Orogenic processes developing early during the history or orogenesis challenge scientists because compositional la... FIAs have been used extensively for more than a decade to unravel deformation and metamorphic puzzles. Orogenic processes developing early during the history or orogenesis challenge scientists because compositional layering in rocks always reactivates where multiple deformations have occurred, leaving little evidence of the history of foliation development preserved in the matrix. The foothills of the Rocky Mountains in Colorado, USA contain a succession of four FIA sets (trends) that would not have been distinguishable if porphyroblasts had not grown during the multiple deformation events that affected these rocks or if they had rotated as these events took place. They reveal that both the partitioning of deformation and the location of isograds changed significantly as the deformation proceeded. 展开更多
关键词 foliation intersection/inflection axes PORPHYROBLAST deformational partitioning
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Resolving the Routine Presence of Kyanite, Andalusite and Sillimanite across a Region using Foliation Intersection/Inflection Axes Preserved in Porphyroblasts, Petrographic Observations and Thermobarometry 被引量:3
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作者 Asghar ALI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第5期1241-1250,共10页
Constraints from P-T pseudosections (MnNCKFMASH system), foliation intersection/ inflection axes preserved in porphyroblasts (FIAs), mineral assemblages and textural relationships for rocks containing all three Al... Constraints from P-T pseudosections (MnNCKFMASH system), foliation intersection/ inflection axes preserved in porphyroblasts (FIAs), mineral assemblages and textural relationships for rocks containing all three Al2 SiO5 polymorphs indicate a kyanite→ andalusite→ sillimanite sequential formation at different times rather than stable coexistence at the Al2SiO5 triple point. All three Al2SiO5 polymorphs grew in the Chl, Bt, Ms, Grt, St, Pl and Crd bearing Ordovician Clayhole Schist in Balcooma, northeastern Australia separately along a looped P-T-t-D path that swaps from clockwise to anticlockwise in the tectono-metamorphic history of the region. Kyanite grew during crustal thickening in an Early Silurian Orogenic event followed by decompression/heating, andalusite and fibrolitic sillimanite growth during Early Devonian exhumation. 展开更多
关键词 Al2SiO5 triple point microtextures foliation intersection/inflection axes Barrovian sequence episodic porphyroblast growth
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Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations 被引量:9
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作者 QU Chang-Zheng ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期577-582,共6页
Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to n... Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach. 展开更多
关键词 symmetry group group foliation method nonlinear wave equation functional separation of variables
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Functional Separable Solutions to Nonlinear Diffusion Equations by Group Foliation Method 被引量:5
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作者 HU Jia-Yi QU Chang-Zheng YIN Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期193-199,共7页
We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to thi... We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to this equation is studied by using the group foliation method. A classification is carried out for the equations which admit the function separable solutions. As a consequence, some solutions to the resulting equations are obtained. 展开更多
关键词 group foliation method functional separation of variable nonlinear diffusion equation symmetry group
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Formation of Foliations and their Related Minerals from Diagenetic to Medium-grade Metamorphic Rocks:A Case Study of the Hongyanjing and Liao-Ji Backarc Basins,China 被引量:1
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作者 TIAN Zhonghua WEN Fei +2 位作者 LIU Fulai ZHU Haozhong YE Zhanghuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第4期1158-1170,共13页
Deciphering the relationship between polyphase tectonic foliations and their associated mineral assemblages is significant in understanding the process from diagenesis to low-/medium-/high-grade metamorphism.It can pr... Deciphering the relationship between polyphase tectonic foliations and their associated mineral assemblages is significant in understanding the process from diagenesis to low-/medium-/high-grade metamorphism.It can provide information related to strain,metamorphic conditions and overprinting relationships and so help reveal the tectonic evolution of orogenesis.In this study,we predominately focus on the formation of foliations and their related minerals,as developed in two separate basins.First of all,two stages of axial plane cleavages(S1 and S2)were recognized in the Hongyanjing inter-arc basin,the formation of the S1 axial plane cleavage is associated with mica rotation and elongation in mudstones in the local area.The pencil structure of S2 formed during the refolding phase,the minerals in the sedimentary rocks not changing their shape and orientation.Secondly,in the Liao-Ji backarc basin,foliations include diagenetic foliation(bedding parallel foliation),tectonic S1 foliation(secondary foliation or axial plane cleavage of S0 folding)and crenulation cleavage(S2).The formation mechanism of foliation changes from mineral rotation or elongation and mineral solution transfer in S1 to crystal-plastic deformation,dynamic recrystallization and micro-folding in S2.Many index metamorphic minerals formed from low-grade to medium-grade consist of biotites,garnets,staurolite and kyanite,constituting a typical Barrovian metamorphic belt.Accordingly,a new classification of foliation is presented in this study.The foliations can be divided into continuous and disjunctive foliations,based on the existence of microlithons,detectable with the aid of a microscope.Disjunctive foliation can be further sub-divided into spaced foliation and crenulation cleavage,according to whether(or not)crenulation(micro-folding)is present.The size of the mineral grains is also significant for classification of the foliations. 展开更多
关键词 new classification of foliations mineral transformation OROGENESIS Hongyanjing basin Liao-Ji backarc basin
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Role of stress,slenderness and foliation on large anisotropic deformations at deep underground excavations 被引量:1
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作者 Bo Hu Mostafa Sharifzadeh +2 位作者 Xiating Feng Wenbin Guo Roo Talebi 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第4期577-590,共14页
High stress concentrations around underground excavations can result in significant damage to deep hard-rock mines.These conditions can be the result of stopping activities,blasting,seismicity,or other mining activiti... High stress concentrations around underground excavations can result in significant damage to deep hard-rock mines.These conditions can be the result of stopping activities,blasting,seismicity,or other mining activities.Large anisotropic deformation and excavation closure,especially under high-stress conditions,are expected if the excavation is located in a foliated or thin-bedded rock mass.In this research,the behaviour of excavations under deep and high-stress conditions was investigated and categorised.The main purpose was to enhance the existing knowledge of managing large anisotropic deformations and to help prepare suitable measures for handling such contingencies.Numerical simulations using the distinct element method(DEM)and model calibration were performed to reproduce the anisotropic deformation of an ore drive based on the collected field data.Then,the roles of key factors(i.e.stress ratio,slenderness ratio,foliation orientation,and foliation considering excavation orientation)on the large deformation and damage depth of the excavations were investigated.This study found that increasing both the stress ratio and slenderness ratio induced linear increases in wall closure and damage depth,whereas increasing the foliation angle first increases the deformation and damage depth and then reduces them both before and after 45.The wall closure and damage thickness decreased with increasing orientation intercept.The deformation and damage levels were classified based on these factors. 展开更多
关键词 Large anisotropic deformation Buckling Deep mining Slenderness ratio Intercept angle foliation orientation
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A Note on Totally Real Riemannian Foliations with Parallelized Mean Curvature Vectors in a Complex Projective Space
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作者 PENG Hui-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期410-414,共5页
We discussed a totally real Riemannian foliations with parallel mean curvature on a complex projective space.We carried out the divergence of a vector field on it and obtained a formula of Simons’type.
关键词 Riemannian foliations complex projective space mean curvature DIVERGENCE
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冀东金厂峪金矿剪切带控矿规律及找矿建议
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作者 鄂建新 缪广 +2 位作者 宁腾霄 郭运晨 张强 《世界有色金属》 2024年第1期82-84,共3页
冀东金厂峪金矿为典型受构造作用控制的矿床,金矿体主要产于NNE向脆-韧性片理化带内的强变形带之中,直接控矿构造为叠加于强变形带之上的NNE向燕山期脆性断裂构造。本文在详细的野外调查基础上进行了构造分期配套,建立了弱变形域控岩+... 冀东金厂峪金矿为典型受构造作用控制的矿床,金矿体主要产于NNE向脆-韧性片理化带内的强变形带之中,直接控矿构造为叠加于强变形带之上的NNE向燕山期脆性断裂构造。本文在详细的野外调查基础上进行了构造分期配套,建立了弱变形域控岩+强变形带赋矿的透镜体控矿模式,结合矿体赋存和矿化富集规律总结,提出了韧脆性片理化带深部、两侧次级平行构造等找矿方向。 展开更多
关键词 冀东 金厂峪金矿 脆-韧性变形 片理化带 强变形带 弱变形域
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羊巴贝斯虫病流行病学的研究进展
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作者 顾月月 薄震宇 +7 位作者 刘欣超 郑克雷 李惠虹 周金星 靳二辉 李文超 胡忠泽 顾有方 《中国动物传染病学报》 CAS 北大核心 2024年第3期221-226,共6页
羊巴贝斯虫病是一种由硬蜱传播的血液原虫病,呈全球性分布,主要临床症状为发热、四肢无力、贫血、腹泻、反刍减弱、厌食、精神不振、虚弱等,严重可导致死亡。本文阐述了巴贝斯虫病病原的种类,并对感染羊的莫氏巴贝斯虫、绵羊巴贝斯虫、... 羊巴贝斯虫病是一种由硬蜱传播的血液原虫病,呈全球性分布,主要临床症状为发热、四肢无力、贫血、腹泻、反刍减弱、厌食、精神不振、虚弱等,严重可导致死亡。本文阐述了巴贝斯虫病病原的种类,并对感染羊的莫氏巴贝斯虫、绵羊巴贝斯虫、粗糙巴贝斯虫、泰氏巴贝斯虫和叶状巴贝斯虫的流行病学情况进行了总结,为羊巴贝斯虫病的防控提供一定的依据。 展开更多
关键词 巴贝斯虫病 绵羊巴贝斯虫 莫氏巴贝斯虫 粗糙巴贝斯虫 泰氏巴贝斯虫 叶状巴贝斯虫
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Anisotropic shearing mechanism of Kangding slate:Experimental investigation and numerical analysis
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作者 Ping Liu Quansheng Liu +4 位作者 Penghai Deng Yucong Pan Yiming Lei Chenglei Du Xianqi Xie 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1487-1504,共18页
The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground engineering.The shear strength and failure mechanisms of layered rock are significantly ... The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground engineering.The shear strength and failure mechanisms of layered rock are significantly affected by the foliation angles.Direct shear tests were conducted on cubic slate samples with foliation angles of 0°,30°,45°,60°,and 90°.The effect of foliation angles on failure patterns,acoustic emission(AE)characteristics,and shear strength parameters was analyzed.Based on AE characteristics,the slate failure process could be divided into four stages:quiet period,step-like increasing period,dramatic increasing period,and remission period.A new empirical expression of cohesion for layered rock was proposed,which was compared with linear and sinusoidal cohesion expressions based on the results made by this paper and previous experiments.The comparative analysis demonstrated that the new expression has better prediction ability than other expressions.The proposed empirical equation was used for direct shear simulations with the combined finite-discrete element method(FDEM),and it was found to align well with the experimental results.Considering both computational efficiency and accuracy,it was recommended to use a shear rate of 0.01 m/s for FDEM to carry out direct shear simulations.To balance the relationship between the number of elements and the simulation results in the direct shear simulations,the recommended element size is 1 mm. 展开更多
关键词 ANISOTROPY Empirical expression of cohesion foliation angles Combined finite-discrete element method(FDEM) Shear rate Element size
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Geochemical Characteristics of Pb Isotope of High-Pressure Metamorphic Rocks and Foliated Granites from HP Unit of Tongbai-Dabie Orogenic Belt 被引量:3
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作者 Zhang Li Zhang Hongfei Zhong Zengqiu Zhang Benren Wang Linsen Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第4期321-329,共9页
Whole-rock Pb isotopic compositions of the high-pressure (HP) metamorphic rocks, consisting of two-mica albite gneisses and eclogites, and foliated granites from the HP metamorphic unit of the Tongbai-Dabie orogenic b... Whole-rock Pb isotopic compositions of the high-pressure (HP) metamorphic rocks, consisting of two-mica albite gneisses and eclogites, and foliated granites from the HP metamorphic unit of the Tongbai-Dabie orogenic belt are firstly reported in this paper. The results show that the HP metamorphic rocks in different parts of this orogenic belt have similar Pb isotopic compositions. The two- mica albite gneisses have 206 Pb/ 204 Pb=17.657-18.168, 207 Pb/ 204 Pb=15.318-15.573, 208 Pb/ 204 Pb=38.315-38.990, and the eclogites have 206 Pb/ 204 Pb=17.599-18.310, 207 Pb/ 204 Pb=15.465- 15.615 , 208 Pb/ 204 Pb=37.968-39.143. The HP metamorphic rocks are characterized by upper crustal Pb isotopic composition. Although the Pb isotopic composition of the HP metamorphic rocks partly overlaps that of the ultrahigh-pressure (UHP) metamorphic rocks, as a whole, the former is higher than the latter. The high radiogenic Pb isotopic composition for the HP metamorphic rocks confirms that the subducted Yangtze continental crust in the Tongbai-Dabie orogenic belt has the chemical structure of increasing radiogenic Pb isotopic composition from lower crust to upper crust. The foliated granites, intruded in the HP metamorphic rocks post the HP/UHP metamorphism, have 206 Pb/ 204 Pb=17.128-17.434, 207 Pb/ 204 Pb=15.313-15.422 and 208 Pb/ 204 Pb=37.631-38.122, which are obviously different from the Pb isotopic compositions of the HP metamorphic rocks but similar to those of the UHP metamorphic rocks and the foliated garnet-bearing granites in the UHP unit. This shows that the foliated granites from the HP and UHP units have common magma source. Combined with the foliated granites having the geochemical characteristics of A-type granites, it is suggested that the magma for the foliated granites in the UHP and HP unit would be derived from the partial melting of the retrometamorphosed UHP metamorphic rocks exhumed into middle to lower crust, and partial magmas were intruded into the HP unit. 展开更多
关键词 Tongbai-Dabie orogenic belt high-pressure metamorphic rocks foliated granites Pb isotope geochemical characteristics.
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Transverse Dimension of R^n Actions on Compact Foliated Manifolds
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作者 Francisco Javier 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第4期86-97,共12页
Consider a foliate Rn-action on a compact connected foliated manifold (M,F). Let mand r be the codimension of F and the (transverse)rank of (M,F)respectively. Suppose r<m.In this paper we prove that either there ex... Consider a foliate Rn-action on a compact connected foliated manifold (M,F). Let mand r be the codimension of F and the (transverse)rank of (M,F)respectively. Suppose r<m.In this paper we prove that either there exists an orbit of the Rn-action of transverse dimension< (m + r)/2 or F can be arbitrarily approached by foliations with rank≥r+1. Moreover weshow that this kind of orbits exists in the following three cases: if F is Riemannian ;when all itsleaves are closed or if X(M)≠0(then r=0).On the other hand all foliate Rn-action on (S3,F) has a fixed leaf if dimF=1.Our result generalies a well known Lima's theorem about Rn-actions on surfaces. 展开更多
关键词 transverse action foliation
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Harmonic Maps and Bi-Harmonic Maps on CR-Manifolds and Foliated Riemannian Manifolds
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作者 Shinji Ohno Takashi Sakai Hajime Urakawa 《Journal of Applied Mathematics and Physics》 2016年第12期2272-2289,共18页
This is a survey on our recent works on bi-harmonic maps on CR-manifolds and foliated Riemannian manifolds, and also a research paper on bi-harmonic maps principal G-bundles. We will show, (1) for a complete strictly ... This is a survey on our recent works on bi-harmonic maps on CR-manifolds and foliated Riemannian manifolds, and also a research paper on bi-harmonic maps principal G-bundles. We will show, (1) for a complete strictly pseudoconvex CR manifold , every pseudo bi-harmonic isometric immersion  into a Riemannian manifold of non-positive curvature, with finite energy and finite bienergy, must be pseudo harmonic;(2) for a smooth foliated map of a complete, possibly non-compact, foliated Riemannian manifold into another foliated Riemannian manifold, of which transversal sectional curvature is non-positive, we will show that if it is transversally bi-harmonic map with the finite energy and finite bienergy, then it is transversally harmonic;(3) we will claim that the similar result holds for principal G-bundle over a Riemannian manifold of negative Ricci curvature. 展开更多
关键词 foliation Divergence Theorem Transversally Harmonic Transversally Biharmonic
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老挝色贡省TL金铅矿地质特征及成矿潜力分析 被引量:1
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作者 张彦伟 曹锦元 +2 位作者 牛英杰 刘威 邢全力 《有色矿冶》 2023年第6期1-5,共5页
老挝色贡省TL金铅矿位于波昆成矿区Samouay-VangTat金多金属成矿带上。通过遥感、地质调查、地球化学测量等手段快速锁定靶区,利用地物化综合剖面和激电测深进行异常查证及矿化蚀变信息提取,借助钻探对在寒武-奥陶系变质岩中发现的含金... 老挝色贡省TL金铅矿位于波昆成矿区Samouay-VangTat金多金属成矿带上。通过遥感、地质调查、地球化学测量等手段快速锁定靶区,利用地物化综合剖面和激电测深进行异常查证及矿化蚀变信息提取,借助钻探对在寒武-奥陶系变质岩中发现的含金、铅等多金属构造片理化带进行工程控制。区内岩石、构造及蚀变矿化特征表明TL金铅矿是受构造控制的造山型金矿。该区及外围存在多条与之特征相似的含金构造片理化带,预示所在区域有着优越的成矿潜力。 展开更多
关键词 老挝色贡 金铅矿 构造片理化带 成矿潜力
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藏北羌塘中部晚古生代增生杂岩的发现及其地质意义 被引量:52
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作者 王根厚 韩芳林 +2 位作者 杨运军 李元庆 崔江利 《地质通报》 CAS CSCD 北大核心 2009年第9期1181-1187,共7页
西藏中部羌塘变质岩带发育复理石碎屑建造和片理化玄武岩建造,都经历了强烈的构造置换作用;还发育早—晚古生代大理岩岩片、无根勾状褶皱和大理岩与蓝片岩组成的同斜褶皱,不同时代的榴辉岩呈岩块出露。这些地质体呈岩片产出,经历了多期... 西藏中部羌塘变质岩带发育复理石碎屑建造和片理化玄武岩建造,都经历了强烈的构造置换作用;还发育早—晚古生代大理岩岩片、无根勾状褶皱和大理岩与蓝片岩组成的同斜褶皱,不同时代的榴辉岩呈岩块出露。这些地质体呈岩片产出,经历了多期构造叠加和置换,原岩总体为碎屑岩、泥质岩、硅质岩、碳酸盐岩及枕状玄武岩、辉长岩建造。宏观上发育明显的区域性置换面理,为典型的造山带增生杂岩。 展开更多
关键词 西藏 羌塘 增生杂岩 面理置换
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大别山超高压变质带面理化榴辉岩中变形石榴石的几何学和运动学特征及其大地构造意义 被引量:21
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作者 徐树桐 刘贻灿 +3 位作者 苏文 吴维平 江来利 王汝成 《岩石学报》 SCIE EI CAS CSCD 北大核心 1999年第3期321-337,共17页
大别山东部双河附近面理化榴辉岩中, 所有榴辉岩相矿物包括石榴石、绿辉石乃至金红石都受到强烈拉伸。用透射电镜可以观察到石榴石晶体中塑性变形的显微构造, 包括自由位错、位错环、位错壁和位错网。拉伸石榴石的应变轴比表现为 X... 大别山东部双河附近面理化榴辉岩中, 所有榴辉岩相矿物包括石榴石、绿辉石乃至金红石都受到强烈拉伸。用透射电镜可以观察到石榴石晶体中塑性变形的显微构造, 包括自由位错、位错环、位错壁和位错网。拉伸石榴石的应变轴比表现为 X> Y> Z。运动学标志如石榴石的不对称碎斑和旋转的金红石颗粒, 表明有旋转应变的作用。石榴石和金红石的福林系数分别为118 和098。所有这些都表明石榴石是在接近于平面应变的条件下形成。由于石榴石颗粒在应变前后体积未变,因此也是在简单剪切作用条件下形成的。根据石榴石韧性变形要求的温度条件, 此种变形应在榴辉岩相条件下发生, 代表一次向南的逆冲作用, 经过展开后, 逆冲的方向为南西。根据石榴石的流变律, 其韧性变形的最低温度估计约为 800℃。石榴石中普遍有一组透入性破劈理, 它产生于面理化榴辉石折返后的角闪岩相早期, 形成于石榴石韧性变形之后。破劈理及其中反S形破劈理的运动指向表明有向北的滑动, 发生在主簿源复背斜形成之前; 主簿源复背斜使面理化榴辉岩的产状由倾向北改变为倾向南。根据面理化榴辉岩及其围岩的同位素年龄, 估算出面理化榴辉岩在200~190 Ma 期间的平均垂直折返速率为9m m /a。此外, 展开更多
关键词 榴辉岩 变形石榴石 几何学 运动学 大地构造意义
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脑梗死患者血清同型半胱氨酸与颈动脉硬化关系的研究 被引量:8
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作者 王荔 连霞 +2 位作者 韩彦青 薛国芳 李光来 《中国神经免疫学和神经病学杂志》 CAS 2006年第3期166-168,共3页
目的研究脑梗死患者血清同型半胱氨酸(homocysteine,Hcy)水平及其与颈动脉硬化的关系。方法收集230例脑梗死患者、180例健康对照者血液标本,采用荧光偏振免疫法测定Hcy、叶酸和维生素B12及酶法测定血脂水平。同时对165例患者作颈动脉超... 目的研究脑梗死患者血清同型半胱氨酸(homocysteine,Hcy)水平及其与颈动脉硬化的关系。方法收集230例脑梗死患者、180例健康对照者血液标本,采用荧光偏振免疫法测定Hcy、叶酸和维生素B12及酶法测定血脂水平。同时对165例患者作颈动脉超声检查并按动脉硬化的程度分组,比较不同程度颈动脉硬化组血清Hcy水平变化。结果脑梗死组患者血清Hcy水平显著高于对照组(P<0.05),血清Hcy与叶酸,维生素B12呈明显负相关(P<0.05),随着颈动脉病变程度加重血清Hcy水平呈上升趋势,且高Hcy检出率增高。结论高Hcy血症是脑梗死的独立危险因素,与颈动脉硬化程度有关,高血Hcy水平的主要原因可能与缺乏叶酸、维生素B12有关。 展开更多
关键词 同型半胱氨酸 脑梗死 颈动脉硬化 叶酸 维生素B12
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深部地壳镁铁质岩石(斜长角闪岩)叶理的组成及形成机制分析——以辽东海城地区变质镁铁质岩石为例 被引量:3
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作者 关会梅 刘俊来 +1 位作者 张崧 张艳彬 《世界地质》 CAS CSCD 2003年第4期344-351,共8页
 高级变质镁铁质岩石叶理形成于地壳深部环境,对其组成及形成机制的深入研究有助于讨论在深部地壳(下地壳)环境中岩石的表现与流动过程。以辽宁海城马风地区广泛出露的斜长角闪岩为例,对变质镁铁质岩石中几种不同类型叶理的组成及形成...  高级变质镁铁质岩石叶理形成于地壳深部环境,对其组成及形成机制的深入研究有助于讨论在深部地壳(下地壳)环境中岩石的表现与流动过程。以辽宁海城马风地区广泛出露的斜长角闪岩为例,对变质镁铁质岩石中几种不同类型叶理的组成及形成机制进行初步探讨。显微构造分析结果表明,变质斜长角闪岩中主要发育三种具有不同特点的叶理构造型式:条带状、糜棱状和片麻状。作为岩石叶理的主要组成矿物,角闪石对叶理的形成贡献最大。斜长石在不同类型岩石中对叶理的形成作用不同。组成叶理的斜长石和角闪石矿物对的温压测算结果表明,它们形成于426~532MPa和581℃~639℃之间。变质基性岩中叶理的形成是这种温度和压力条件下多种机制(包括晶体的定向重结晶作用、应力作用下的变质分异、晶质塑性变形、亚颗粒旋转动态重结晶)共同作用的结果。 展开更多
关键词 斜长角闪岩 叶理 变形机制 显微构造 下部地壳
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三叶木通优选单株果实的营养品质特性 被引量:21
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作者 仲伟敏 马玉华 《贵州农业科学》 CAS 2015年第1期140-142,共3页
为明确三叶木通果实的营养成分和综合开发利用价值,对其优选单株的果实营养品质进行了分析。结果表明,三叶木通果实含粗蛋白2.52g,粗脂肪1.4g,粗纤维6.7g,15种氨基酸总量为19.01mg/g,人体必需氨基酸占58.08%,药用氨基酸占53.60%,甜味氨... 为明确三叶木通果实的营养成分和综合开发利用价值,对其优选单株的果实营养品质进行了分析。结果表明,三叶木通果实含粗蛋白2.52g,粗脂肪1.4g,粗纤维6.7g,15种氨基酸总量为19.01mg/g,人体必需氨基酸占58.08%,药用氨基酸占53.60%,甜味氨基酸(Ser,Gly,Ala)占16.36%;三叶木通果实中矿质元素含量丰富,常量元素含量K>P>Mg>Ca>Na,微量元素含量Fe>Mn>Zn>Cu>Se,还含有糖、酸和维生素等,是一种集营养、药用、保健功能于一体的果品。 展开更多
关键词 三叶木通 营养品质 优选单株
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