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中澳Woodroffe逆冲糜棱岩带内斜长石和钾长石在变形和重结晶过程中的变形分异作用 被引量:3
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作者 T.H.Bell S.E.Johnson +1 位作者 王绍华 王海金 《世界地质》 CAS CSCD 1990年第4期173-187,共15页
在中澳Woodroffe逆冲糜棱岩带内,斜长石及钾长石的重结晶作用涉及到亚颗粒的旋转和相关的颗粒边界或扭折带边界的膨胀,而与主颗粒至新颗粒之间的化学成分变化无关。亚颗粒和新颗粒的粒度沿糜棱岩带横向变化,明显是岩石应变速率和岩石含... 在中澳Woodroffe逆冲糜棱岩带内,斜长石及钾长石的重结晶作用涉及到亚颗粒的旋转和相关的颗粒边界或扭折带边界的膨胀,而与主颗粒至新颗粒之间的化学成分变化无关。亚颗粒和新颗粒的粒度沿糜棱岩带横向变化,明显是岩石应变速率和岩石含水量的函数。糜棱岩化过程中,渐进剪切作用和渐进缩短作用带内的变形分异控制了长石恢复和重结晶的位置。在发育完好的糜棱岩中,长石残斑的粒度受糜棱岩化早期阶段,也就是在大量能调节渐进剪切变形组分的细粒基质形成之前,就受到变形分异程度的控制。由于格子状双晶的长石新颗粒通常靠近格子状双晶的长石主颗粒,重结晶作用就发生在微斜长石中,明显地没有涉及到向单斜结构的转变。由XRD轨道计算出来的钾长石三针度从糜棱岩带边缘向内部增加,与变形强度相对应。斜长石主颗粒局部具有正长石或不具双晶的微斜长石核,核周围环绕具双晶的微斜长石慢,说明了格子状双晶的存在与钾长石三斜度之间的关系。 展开更多
关键词 变形分异作用 钾长石三斜度 糜棱岩 斜长石 重结晶作用
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河南省煤田构造格局对煤层气储层物性和渗流特征的影响 被引量:1
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作者 赵发军 于兴腾 +1 位作者 郝富昌 刘彦伟 《煤田地质与勘探》 CAS CSCD 北大核心 2018年第4期61-66,71,共7页
为了查明河南省不同构造区内二1煤层中气体的流动特征和煤体受构造变形分异后的独特性,采用实验数据分析、瓦斯地质和渗流学理论,研究煤中孔容分布、孔径受应力影响后的变化以及煤体强度受构造应力作用下的变形和破坏特点。结果表明,煤... 为了查明河南省不同构造区内二1煤层中气体的流动特征和煤体受构造变形分异后的独特性,采用实验数据分析、瓦斯地质和渗流学理论,研究煤中孔容分布、孔径受应力影响后的变化以及煤体强度受构造应力作用下的变形和破坏特点。结果表明,煤层中甲烷连续流型占优的排序为:太行构造区、崤熊构造区、嵩萁构造区。煤中甲烷流型差异受区域构造变形体制控制,太行构造区的拉伸变形导致煤体强度值域分布广,最大体应变大于其他区域;嵩萁构造区的重力滑动、剪切和伸展变形使煤体强度和孔隙率最低、最大体应变最小;崤熊构造区内煤体的最大体应变介于两者之间。该结论对河南省煤层气开发有指导意义。 展开更多
关键词 煤田构造 变形分异 甲烷流动 煤体强度
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Combined goblet cell carcinoid and mucinous cystadenoma of the vermiform appendix 被引量:6
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作者 Khaled O Alsaad Stefano Serra Runjan Chetty 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第27期3431-3433,共3页
Goblet cell carcinoid is an uncommon primary tumor of the vermiform appendix, characterized by dual endocrine and glandular differentiation. Whether goblet cell carcinoid represents a morphological variant of appendic... Goblet cell carcinoid is an uncommon primary tumor of the vermiform appendix, characterized by dual endocrine and glandular differentiation. Whether goblet cell carcinoid represents a morphological variant of appendiceal classical carcinoid or a mucin-producing adenocarcinoma is a matter of conjecture. Rare cases of goblet cell carcinoid with other concomitant appendiceal epithelial neoplasms have been documented. In this report, we describe a rare case of combined appendiceal goblet cell carcinoid and mucinous cystadenoma, and discuss the possible histopathogenesis of this combination. 展开更多
关键词 Goblet cell carcinoid Mucinous cystadenoma Vermiform appendix
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Comparative Analysis of Morphologic Traits of 50 Large-flowered Chrysanthemum Varieties
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作者 沈珍 毛燕 +2 位作者 吴德智 袁伟 杨旭 《Agricultural Science & Technology》 CAS 2016年第2期317-322,共6页
With 50 large-flowered Chrysanthemum varieties from germplasm nursery of Wunaoshan Forest Farm in Macheng City as research objects, 64 morphological traits were investigated by field experiments adopting randomized bl... With 50 large-flowered Chrysanthemum varieties from germplasm nursery of Wunaoshan Forest Farm in Macheng City as research objects, 64 morphological traits were investigated by field experiments adopting randomized block design. The morphological differences were observed by uniformity analysis, variability analysis, principal component analysis and cluster analysis. The result showed that the vari- able coefficients of 59 traits were greater than 15%; the contribution rate of first seven principal components reached 81.45%; and it was found by clustering analy- sis that the 50 germplasm resources could be divided into four clusters with obvious morphological differences, and plant type could be used as an index for classifica- tion. 展开更多
关键词 Large-flowered Chrysanthemum Morphologic traits Variability analysis Principal component analysis Clustering analysis
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Strain anisotropy models for refined diffraction line profile analysis in cubic metals 被引量:1
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作者 Xiang DAI Fu-lin JIANG +4 位作者 Jin LIU Luo-yi WU Ding-fa FU Jie TENG Hui ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第8期2090-2106,共17页
The present work examined the anisotropy magnitudes obtained from different elastic models of cubic metals(Cu,5383 Al alloy,FCC austenite steel and BCC steel)to explore the origin of strain anisotropy.The results show... The present work examined the anisotropy magnitudes obtained from different elastic models of cubic metals(Cu,5383 Al alloy,FCC austenite steel and BCC steel)to explore the origin of strain anisotropy.The results showed that stable intersections were observed from the modeled and experimental plots of the reciprocal elastic modulus(1/Ehkl)and orientation parameter(Γ).The effectiveness of quasi elasto-plastic model based method in correcting strain anisotropy was further verified in cold-worked specimens.For the important input parameters in dislocation model based diffraction line profile analysis methods,the average diffraction contrast factors(■)of dislocations were observed to depend on elastic constants.Interesting intersections were found from linear dependence of■onΓ.The conventional input■values indicated distinct dependencies on given elastic constants in diffraction line profile analysis.Accordingly,a refined approach was proposed by adopting the optimized intersections as input values,by which more reliable results could be obtained in practical applications. 展开更多
关键词 metallic materials line profile analysis strain anisotropy dislocations
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Redistribution and magnitude of stresses around horse shoe and circular excavations opened in anisotropic rock 被引量:6
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作者 Mambou Ngueyep Luc Leroy Ndop Joseph Ndjaka Jean-Marie Bienvenu 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期615-621,共7页
In this paper numerical analysis of underground structures, taking account the transverse isotropy system of rocks, was done using CAST 3M code by varying the shape of excavation and the coefficient of earth pressure ... In this paper numerical analysis of underground structures, taking account the transverse isotropy system of rocks, was done using CAST 3M code by varying the shape of excavation and the coefficient of earth pressure k. Numerical results reveal that the anisotropy behavior, the shape of hole and the coefficient of earth pressure k have significant influence to the mining induced stress field and rock deformations which directly control the stability of underground excavation design. The magnitude of horizontal stress obtained for the horse shoe shape excavation(25.2 MPa for k = 1; 52.7 MPa for k = 2)is lower than the magnitude obtained for circular hole(26.4 MPa for k = 1; 59.5 MPa for k = 2).Therefore, we have concluded that the horse shoe shape offers the best stability and the best design for engineer. The anisotropy system presented by rock mass can also influence the redistribution of stresses around hole opened. Numerical results have revealed that the magnitude of redistribution of horizontal stresses obtained for transverse isotropic rock(12.1 MPa for k = 0.5; 25.2 MPa for k = 1 and52.7 MPa for k = 2) is less than those obtained in the case of isotropic rock(27.6 MPa for k = 1;48.6 MPa for k = 2 and 90.81 MPa for k = 2). The more the rock has the anisotropic behavior, the more the mass of rock around the tunnel is stable. 展开更多
关键词 Horse shoe excavation Stress Strain Transverse isotropy Finite element
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Morphological Variation of Donax spp. from Five Beaches in Prachaupkhirikhan, Thailand
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作者 S. Manatrinon O. U. Thonglor A. Boonyapakdee 《Journal of Agricultural Science and Technology(A)》 2011年第8期1109-1111,共3页
Five hundred samples ofDonax spp. were collected from five beaches (Khao Tao, Sea Pine Garden, Pran Buri Forest Park, Sam Roi Yod, and Sam Phraya) in Prachaupkhirikhan province, Thailand. Five morphological variable... Five hundred samples ofDonax spp. were collected from five beaches (Khao Tao, Sea Pine Garden, Pran Buri Forest Park, Sam Roi Yod, and Sam Phraya) in Prachaupkhirikhan province, Thailand. Five morphological variables of each individual were measured and analyzed to reveal morphological variation. The discriminant function analysis of morphology suggested a clear separation into two groups. The individuals from Khao Tao and Sea Pine Garden were grouped together while individuals from Pran Buri Forest Park, Sam Roi Yod and Sam Phraya were classified into the same group. The classification function of discriminant function analysis suggested that 70% of Khao Tao population, 70% of Sea Pine Garden population, 67% of Pran Buri Forest Park population, 64% of Sam Roi Yod population and 34% of Sam Phraya population of Donax spp. could be correctly reassigned by morphology. The misclassification individuals of Sam Phraya population were assigned to Pran Buri Forest Park and Sam Roi Yod population with the correct assignment 38% and 27%, respectively. The results obtained in this study based on morphological variation indicated that Khao Tao and Sea Pine Garden populations ofDonax spp. should be treated as separated units from the other three populations for conservation management. However, the result should be confirmed again as genetic level. 展开更多
关键词 Morphological variation discriminant function analysis Donax spp. Prachaupkhirikhan
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Cloning and stage-specific expression of CK-M1 gene during metamorphosis of Japanese flounder,Paralichthys olivaceus
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作者 陈妍婕 张全启 +6 位作者 齐洁 王志刚 王旭波 孙业盈 钟其旺 李朔 李春梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期558-564,共7页
The symmetrical body of flatfish larvae changes dramatically into an asymmetrical form after metamorphosis. The molecular mechanisms responsible for this change are poorly understood. As an initial step to clarify the... The symmetrical body of flatfish larvae changes dramatically into an asymmetrical form after metamorphosis. The molecular mechanisms responsible for this change are poorly understood. As an initial step to clarify these mechanisms, we used representational difference analysis of cDNA for the identification of genes active during metamorphosis in the Japanese flounder, Paralichthys olicaceus. One of the up-regulated genes was identified as creatine kinase muscle type 1 (CK-M1). Sequence analysis of CK-M1 revealed that it spanned 1 708 bp and encoded a protein of 382 amino acids. The overall amino acid sequence of the CK-M1 was highly conserved with those of other organisms. CK-M1 was expressed in adult fish tissues, including skeletal muscle, intestine and gill. Whole mount in-situ hybridization showed that the enhanced expression of CK-M1 expanded from the head to the whole body of larvae as metamorphosis progressed. Quantitative analysis revealed stage-specific high expression of CK-M1 during metamorphosis. The expression level of CK-M1 increased initially and peaked at metamorphosis, decreased afterward, and finally returned to the pre-metamorphosis level. This stage-specific expression pattern suggested strongly that CK-M1 was related to metamorphosis in the Japanese flounder. Its specific role in metamorphosis requires further study. 展开更多
关键词 CK-M1 METAMORPHOSIS gene expression Paralichthys olivaceus
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Analysis of Sacks Body Strain Interference at Beida No.200 Station in Changping and Earthquake Case Study
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作者 Li Hangu Hu Lan Wu Lijun 《Earthquake Research in China》 CSCD 2017年第2期269-281,共13页
The relationship between Sacks body strain deformation at Beida No. 200 station in Changping and tidal solids,atmospheric pressure and water level is analyzed in this paper. Sacks body strain deformation data before t... The relationship between Sacks body strain deformation at Beida No. 200 station in Changping and tidal solids,atmospheric pressure and water level is analyzed in this paper. Sacks body strain deformation data before the M_S8. 0 Wenchuan earthquake is studied based on the analysis of the interference. The short-impending anomaly of the body strain deformation is considered to be reliable. The anomaly characteristics conclude:( 1) The trend anomaly as extensional change of the body strain deformations on a quasi 1 year time scale before the Wenchuan earthquake was recorded, and the accumulative amount was about 4000 × 10^(-9). Correspondingly,the short-term precursor of earthquake was manifested as an extensional abrupt change.( 2) The extensional intermittent anomalous abrupt change was recorded by body strainmeters between March1 and May 7 in 2008.( 3) Four compressional abrupt changes were recorded in the intermittent distortions recorded between April 13 and May 11.( 4) High frequency components were increased in the distortion process in May 1 to 3,5,7,and 9 to 12,caused by slow earthquakes before the Wenchuan earthquake according to wavelet analysis. The abnormal phenomena are summarized and the mechanics discussed in this paper. Strain solid tide distortions in body strain observations,the continuous repeated extensional and compressional abrupt changes accompanying these distortions,and the increase of high frequency components can be regarded as the index of short term and impending earthquake prediction,based on analysis of interference factors such as air pressure and water level. 展开更多
关键词 Body strain The solid tide distortion Slow earthquake Short imminent anomalies
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Phenotypic plasticity can explain evolution of sympatric polymorphism in the hairy snail Trochulus hispidus (Linnaeus, 1758) 被引量:2
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作者 Matgorzata PROCKOW Elzbieta KUZNIK-KOWALSKA Pawet MACKIEWICZ 《Current Zoology》 SCIE CAS CSCD 2017年第4期389-402,共14页
Morphological variation of snails from the genus Trochulus is so huge that their taxonomy is unclear. The greatest variability concerns forms hispidus and sericeus/plebeius, which are often considered as separate spec... Morphological variation of snails from the genus Trochulus is so huge that their taxonomy is unclear. The greatest variability concerns forms hispidus and sericeus/plebeius, which are often considered as separate species. To evidence the species barriers, we carried out crossbreeding ex- periments between these two sympatric morphs. Moreover, we compared the shell morphology of laboratory-bred offspring with their wild parents to test if the variation can be explained by the phenotypic plasticity model. We found that the two Trochulus morphs show no reproductive bar- riers. The fecundity rates, the mean clutch size, and F~ viability observed for all crosses were not significantly different. In hybrid crosses (in F2 generation), we also recorded reproduction compati- bility, similar fecundity, and hatching success as in their parents. Accordingly, phylogenetic ana- lyses revealed the significant grouping of sequences from these different morphs and supported no constrains in reproduction between them. Comparison of shell morphology between wild and laboratory samples showed that various characters appeared highly plastic. The average shell shape of the hispidus morph changed significantly from flat with wide umbilicus to elevated with narrower umbilicus such as in the sericeus/plebeius morph. All these findings indicate that the examined morphs do not represent separate biological species and the evolutionary process is not advanced enough to separate their genetic pool. Therefore, phenotypic plasticity has played a sig- nificant role in the evolution of Trochulus shell polymorphism. The two morphs can evolve inde- pendently in separate phylogenetic lineages under the influence of local environmental conditions. 展开更多
关键词 CROSSBREEDING cytochrome c oxidase subunit I molecular phylogeny phenotypic variation principal component analysis shell morphology.
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On the hyperbolicity of flows
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作者 GAN ShaoBo LIU ZhaoNan ZHENG RuSong 《Science China Mathematics》 SCIE CSCD 2016年第4期645-652,共8页
Let X be a C1 vector field on a compact boundaryless Riemannian manifold M(dim M≥2),and A a compact invariant set of X.Suppose that A has a hyperbolic splitting,i.e.,T∧M = Es Eu with Es uniformly contracting and E... Let X be a C1 vector field on a compact boundaryless Riemannian manifold M(dim M≥2),and A a compact invariant set of X.Suppose that A has a hyperbolic splitting,i.e.,T∧M = Es Eu with Es uniformly contracting and Eu uniformly expanding.We prove that if,in addition,A is chain transitive,then the hyperbolic splitting is continuous,i.e.,A is a hyperbolic set.In general,when A is not necessarily chain transitive,the chain recurrent part is a hyperbolic set.Furthermore,we show that if the whole manifold M admits a hyperbolic splitting,then X has no singularity,and the flow is Anosov. 展开更多
关键词 hyperbolicity chain transitive singularity flow
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