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奇形凤仙花的微形态特征及其系统演化意义 被引量:2
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作者 李景照 黄红慧 +2 位作者 高立献 王光明 刘宗才 《植物科学学报》 CAS CSCD 北大核心 2020年第3期301-307,共7页
采用光学显微镜和扫描电镜对奇形凤仙花(Impatiens paradoxa C.S.Chu et H.W.Yang)的叶表皮和花粉形态特征进行观察。结果显示:该物种叶上表皮无气孔器,表皮细胞为不规则多边形,垂周壁波状,表皮外为相邻细胞的壁突起形成的小格子,格子... 采用光学显微镜和扫描电镜对奇形凤仙花(Impatiens paradoxa C.S.Chu et H.W.Yang)的叶表皮和花粉形态特征进行观察。结果显示:该物种叶上表皮无气孔器,表皮细胞为不规则多边形,垂周壁波状,表皮外为相邻细胞的壁突起形成的小格子,格子内具圆形突起结构,其外壁上具有条纹状纹饰;叶下表皮具有两个保卫细胞组成的椭圆形气孔器,下表皮细胞也为不规则多边形,垂周壁深波状,表皮外常具有梭形结构,相邻细胞的垂周壁也突起形成小格子,格子内具有圆形突起结构及条状纹饰;花粉为单粒花粉,极面观矩圆形,长、短赤道面观分别为长、短椭圆形,花粉4沟型,沟分布于4个角的位置,沟细、短且浅,花粉外壁为网状纹饰,网眼明显,网眼内具有突起的不均匀颗粒物。对该特有种的外部形态、叶表皮形态和花粉形态的系统学意义进行了讨论,认为该种是一个高度特化的类群。该种花较大呈黄色可以作为优良的观赏植物,该种的自然分布也表明伏牛山和秦岭大巴山脉植物区系的相似性。 展开更多
关键词 凤仙花属 奇形凤仙花 叶表皮 花粉 系统演化 河南
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从奇形异貌圣事角度再论《史记》的实录
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作者 张学成 《齐鲁师范学院学报》 2021年第5期135-141,共7页
《史记》是实录的典型代表,其中却存在大量似与"实录"不相符合的矛盾性描写,其中神神怪怪的人事并不少见,围绕着始祖帝王圣人的神异记载可概括为奇形异貌圣事。围绕刘邦的奇形异貌圣事,是另一种意义的实录。刘邦神怪之事、田... 《史记》是实录的典型代表,其中却存在大量似与"实录"不相符合的矛盾性描写,其中神神怪怪的人事并不少见,围绕着始祖帝王圣人的神异记载可概括为奇形异貌圣事。围绕刘邦的奇形异貌圣事,是另一种意义的实录。刘邦神怪之事、田单神人教我之事、陈胜吴广鱼书狐叫之事性质上具有紧密联系,属于互见法的范畴,通过别处的"里",就能知晓刘邦神怪现象表象的本质。刘邦神化自己的出生,关于刘邦身上种种神奇的描写,是为了神化自己,达到"君权神授"的目的。 展开更多
关键词 奇形 异貌 圣事 实录 《史记》 互见法
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通背奇形腿法图解(二)
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作者 张秋 《中华武术》 2005年第2期44-46,共3页
动作①右脚在后提膝向上,使右腿成勾两掌同时向左右分抡。(图26)
关键词 通背奇形腿法 动作要领 武术 体育运动
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七种菊科植物SSR标记在大黄橐吾和奇形橐吾杂交区类群中的通用性检测 被引量:1
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作者 张荣 冯秀彦 龚洵 《植物分类与资源学报》 CAS CSCD 北大核心 2015年第4期416-422,共7页
牦牛山橐吾(Ligularia×maoniushanensis)是大黄橐吾(L.duciformis)和奇形橐吾(L.paradoxa)的一个自然杂交种。为了研究大黄橐吾和奇形橐吾杂交区类群的杂交关系和遗传结构,本研究利用两个杂交区杂交种及亲本的94个个体,... 牦牛山橐吾(Ligularia×maoniushanensis)是大黄橐吾(L.duciformis)和奇形橐吾(L.paradoxa)的一个自然杂交种。为了研究大黄橐吾和奇形橐吾杂交区类群的杂交关系和遗传结构,本研究利用两个杂交区杂交种及亲本的94个个体,从来自橐吾属、大吴风草属、千里光属和向日葵属7个种中已开发的145对核SSR引物进行筛选。结果表明在所研究的三个类群中至少能在其中一个类群中成功扩增的位点有54个,都能扩增的位点17个。在这17个位点中,牦牛山橐吾中11个位点具多态性,每个位点有2~14个等位基因,平均为4.8个。观测杂合度和期望杂合度分别为0.053~1.000和0.051~0.887:大黄橐吾中9个位点有多态性,每个位点有3~12个等位基因.平均为7.4个,观测杂合度和期望杂合度分别为0.200~0.971和0.283~0.844;奇形橐吾中10个位点有多态性,每个位点具4,15个等位基因,平均为7.6个,观测杂合度的值为0.025~0.974,期望杂合度的值为0.097~0.846。以上结果对大黄橐吾和奇形橐吾杂交区类群的杂交程度和遗传结构的进一步研究有重要作用。 展开更多
关键词 牦牛山橐吾 大黄橐吾 奇形橐吾 SSR 多态性 通用性
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奇形句
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《少先队小干部(下半月刊)》 2009年第12期38-39,共2页
今天下雨,,我的心也阴沉沉的。因为今天中午轮到我开教室门,我却忘了带钥匙,被老师批评了一顿。回家后,我独自在屋顶上反省了很长时间。
关键词 奇形 小学 语文学习 阅读
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奇形句
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《少先队小干部(下半月刊)》 2009年第10期37-38,共2页
七个小矮人回家了,他们从中拿出今天的报纸读给白雪公主听,一边谈论着今天的趣事。
关键词 小学 语文教学 奇形 阅读
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奇形句
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《少先队小干部(下半月刊)》 2009年第7期74-76,共3页
我正在书房做作业,忽然从客厅传来一阵笑声,吓了我一跳,原来是妈妈正在看喜剧片。我借机赶紧合上书,把书签夹到书里,去喝了一杯饮料,让大脑放松一下。
关键词 小学教育 奇形 语文教学 汉语
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奇形趣味数独
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《知识就是力量》 2013年第4期78-78,23,共2页
请用数字1-9填满空格。使每行、每列、每个用粗线隔开的区域均没有重复的数字。
关键词 智力游戏 游戏方法 游戏规则 奇形趣味数独”
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一种基于PIFS的DWT水印算法
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作者 刘松华 陈亮 丁彩英 《科技广场》 2006年第5期27-29,共3页
本文提出了一种基于分块迭代函数系(PIFS)的小波域水印算法。通过PIFS变换将水印图变换为自相似分形水印图,然后用小波变换进行水印的嵌入、提取。实验证明该算法有良好的鲁棒性,同时保证了水印的不可见性。
关键词 数字水印 分块迭代函数系 奇形 鲁棒性
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基于AutoCAD平台的机器人仿真系统研究
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作者 张永宏 《南京林业大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第2期48-48,共1页
关键词 机器人仿真技术 AUTOCAD AUTOLISP 实体造型模块 运动学模块 奇形异位 干涉
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观赏瓜栽培技术总结 被引量:3
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作者 张丽 《西南园艺》 2005年第2期52-53,共2页
对观赏南瓜、观赏瓠瓜、观赏奇形瓜的栽培技术作了较详细的经验总结,并指出目前观赏瓜栽培中存在的问题及其解决措施。
关键词 观赏南瓜 观赏瓠瓜 观赏奇形 栽培技术 品种选择 播种育苗 定植 园艺管理
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Singular Points, Closed Orbits, Stable Manifolds and Unstable Manifolds of Second Order Autonomous Birkhoff Systems 被引量:1
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作者 陈向炜 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期330-336,共7页
Aim To study singular points, closed orbits, stable manifolds and unstable manifolds of a second order autonomous Birkhoff system. Methods Qualitative methods of ordinary differential equation were used. Results and ... Aim To study singular points, closed orbits, stable manifolds and unstable manifolds of a second order autonomous Birkhoff system. Methods Qualitative methods of ordinary differential equation were used. Results and Conclusion The criteria for singular points, closed orbits and hyperbolic equilibrium points of a second order autonomous Birkhoff system are given. Moreover the stability of equilibria, stable manifolds and unstable manifolds are obtained. 展开更多
关键词 Birkhoff system singular point closed orbit stable manifold unstable manifold
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Choice of conodont Idiognathodus simulator (sensu stricto) as the event marker for the base of the global Gzhelian Stage (Upper Pennsylvanian Series, Carboniferous System) 被引量:5
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作者 Philip H. Heckel Aleksandr S. Alekseev +7 位作者 James E. Barrick Darwin R. Boardman Natalya V. Goreva Tatiana N. Isakova Tamara I. Nemyrovska Katsumi Ueno Elisa Villa David M. Work 《Episodes》 SCIE 2008年第3期319-325,共7页
We propose that the level at which the conodont species Idiognathodus simulator (Ellison 1941) (sensu stricto) first appears be selected to mark the base of the Gzhelian Stage, because we believe that this is the ... We propose that the level at which the conodont species Idiognathodus simulator (Ellison 1941) (sensu stricto) first appears be selected to mark the base of the Gzhelian Stage, because we believe that this is the optimal level by which this boundary can be correlated. This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothems across the Kasimovian-Gzhelian boundary interval among Midcontinent North America and the Moscow and Donets basins of eastern Europe, based on scale of the cyclothems along with several aspects of biostrati- graphy. Outside of these areas, I. simulator (sensu stricto) is known also from other parts of the U.S., and is reported from the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current ammonoid placement of the boundary (first appearance of Shumardites cuyleri), and it is also compatible with certain aspects of the distribution of Eurasian fusulinid faunas (e.g., lectotype ofRauserites rossicus). 展开更多
关键词 颚牙石属 模拟技术 岩石学
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Local Bifurcation of a Thin Rectangle Plate with the Friction Support Boundary
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作者 叶敏 张伟亿 《Transactions of Tianjin University》 EI CAS 2002年第2期114-118,共5页
The dynamical equations of a thin rectangle plate subjected to the friction support boundary and its plane force are established in this paper. The local bifurcation of this system is investigated by using L S method... The dynamical equations of a thin rectangle plate subjected to the friction support boundary and its plane force are established in this paper. The local bifurcation of this system is investigated by using L S method and the singularity theory. The Z 2 bifurcation in non degenerate case is discussed. The local bifurcation diagrams of the unfolding parameters and the bifurcation response characters referred to the physical parameters of the system are obtained by numerical simulation. The results of the computer simulation are coincident with the theoretical analysis and experimental results. 展开更多
关键词 thin rectangle plate L S method singularity theory local bifurcation numerical simulation
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Wave Interaction with Dual Circular Porous Plates 被引量:2
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作者 Arpita Mondal R. Gayen 《Journal of Marine Science and Application》 CSCD 2015年第4期366-375,共10页
In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular... In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular integral equation technique has been used to analyze the problem mathematically. The integral equations are formulated by applying Green's integral theorem to the fundamental potential function and the scattered potential function into a suitable fluid region, and then using the boundary condition on the porous plate surface. These are solved approximately using an expansion-cure-collocation method where the behaviour of the potential functions at the tips of the plates have been used. This method ultimately produces a very good numerical approximation for the reflection and the transmission coefficients and hydrodynamic force components. The numerical results are depicted graphically against the wave number for a variety of layouts of the arc. Some results are compared with known results for similar configurations of dual rigid plate systems available in the literature with good agreement. 展开更多
关键词 water wave scattering circular-arc-shaped plates hypersingular integral equation Green's integral theorem reflection coefficient energy identity hydrodynamic force
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Five Nontrivial Solutions of p-Laplacian Problems Involving Critical Exponents and Singular Cylindrical Potential 被引量:1
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作者 Mohammed el Mokhtar ould el Mokhtar 《Journal of Physical Science and Application》 2015年第2期163-172,共10页
In this paper, we establish the existence of at least five distinct solutions to a p-Laplacian problems involving critical exponents and singular cylindrical potential, by using the Nehari manifold, concentration-comp... In this paper, we establish the existence of at least five distinct solutions to a p-Laplacian problems involving critical exponents and singular cylindrical potential, by using the Nehari manifold, concentration-compactness principle and mountain pass theorem 展开更多
关键词 Nehari manifold concentration-compacmess principle critical Hardy-Sobolev exponent singular cylindrical potential mountain pass theorem nontrivial cylindrical solution.
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Singularity Theory on Buckling of Compressible Slender Rods with Deformation of Cross Section 被引量:2
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作者 张义同 熊成安 谢宇新 《Transactions of Tianjin University》 EI CAS 2006年第2期79-83,共5页
The crucial effect of compressibility of rods on their instability is novelly demonstrated via singularity theory. It is shown that the critical load of compressible rod is always greater than the one of the Euler rod... The crucial effect of compressibility of rods on their instability is novelly demonstrated via singularity theory. It is shown that the critical load of compressible rod is always greater than the one of the Euler rod, and a subcritical pitchfork bifurcation, which cannot occur for the Euler rod, may occur for a compressible rod. A whole bifurcation diagram of compressible rods is as follows : when the original slenderness ratio of a compressible rod, $o is smaller than (1 + v/3 √3π/2,, the rod does not buckle; when So∈ [1+ v/3)3√3π/2 ,(1+v/5)5 5√5π/4),the rod may undergo a subcritical pitchfork bifurcation and a collapse may occur; when So ∈ [1+ v/5)5√5π/4 + ∞), the rod may undergo a supercritical pitchfork bifurcation. The deformation of cross section of rods causes a little shift of bifurcation points towards to the one corresponding to larger slenderness ratio. 展开更多
关键词 singularity theory BUCKLING STABILITY compressible slender rods
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Identity Construction and Image Identification: Evaluative Factors in Promotional Communication
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作者 Maria Teresa Marins Freire Denise Wemeck 《Journalism and Mass Communication》 2013年第1期58-67,共10页
The paper addresses the identity construction in social organizations whose primary role is to define their singularity against other organizations and have them take on this singular role in the minds of its related ... The paper addresses the identity construction in social organizations whose primary role is to define their singularity against other organizations and have them take on this singular role in the minds of its related audiences. This construction is carried out in the course of the organizational existence and it is reflected in the image that it depicts. Those two elements are essential values to be handled by promotional communication through its several channels, means, and products. The aim of the study is to discuss the importance of corporate identity and image in the promotional communication of an organization. Bibliographical research and a case study were both used as methodologies. We have found the need to cultivate a positive image for the consolidation of the future of the organization including the contribution to the economic development of the country. 展开更多
关键词 social organization IDENTITY IMAGE VALUE promotional communication
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Integral Representation of the Manifold Solution for New Class of the Volterra Type Integral Equation with a Boundary Singularity in the Case, When Kernel Contain Logarithmic Singularity and its Power
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作者 Nusrat Rajabov 《Journal of Mathematics and System Science》 2016年第1期23-37,共15页
In this work we suggestion new methods investigation the model Volterra type integral equation with logarithmic singularity, kernel which consisting from composition polynomial function with logarithmic singularity an... In this work we suggestion new methods investigation the model Volterra type integral equation with logarithmic singularity, kernel which consisting from composition polynomial function with logarithmic singularity and function with singular point. The problem investigation this type integral equation at n = 2m reduce to problem investigate the Volterra type integral equation (1) for n = 2 the theory for which was constructed in [2]. In this work, we investigation integral equation (1) at = 2m + 1 In this case, we investigate integral equation (1) reduction it's to m integral equation type [2] φ(x)+∫xa[p1+p2 ln(x-a/t-a)]φ(t)/t-a dt=f(x)and one the following integral equation [1] ω(x)+p3∫xω(t)/ a t-adt=g(x). 展开更多
关键词 singular kernel volterra type integral equation boundary singularity logarithmic singularity.
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A Generalized Form of Whitney's Theorem
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作者 CEN Yan-ming CEN Li-hui 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期75-78,共4页
Whitney's theorem is a famous theorem in the local singularity theory. In this paper, as an application of Malgrange preparation theorem, a generalized form of Whitney's theorem will be derived.
关键词 generalized of Whitney's theorem
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