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Effects of Different Line Spacing and Seedling Belt Width on Yield Formation of Broad-Width Fine Sowing Wheat
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作者 Minmin SHAO Leiming SUN +5 位作者 Kai ZHAO Xingke XU Ling HUANG Lin WANG Lu YAN Zhengchun JU 《Agricultural Biotechnology》 CAS 2020年第3期29-33,共5页
In order to explore the interaction effects of line spacing and seedling belt width on wheat yield formation and improve the cultivation techniques of broadwidth and fine seeding of wheat,a high-yielding winter wheat ... In order to explore the interaction effects of line spacing and seedling belt width on wheat yield formation and improve the cultivation techniques of broadwidth and fine seeding of wheat,a high-yielding winter wheat cultivar Shannong 28 was selected as material. Using the split plot design,the main plot was set with line spacing as 20,25 and 30 cm,respectively,and the sub-plot was set with seedling belt width as 3,5,7,9 and 11 cm,respectively. Then,the population dynamics,dry matter accumulation and translocation and yield of wheat were studied under the experimental conditions. The results showed that under the line spacing of 20 cm,the dry matter accumulation and yield of winter wheat were higher with the seedling belt width of 5 cm. When the line spacing was 25 cm,the dry matter accumulation and yield under the seedling belt width of 9 cm reached a high level. Under the line spacing of 30 cm,Shannong 28 achieved higher dry matter accumulation and yield with the seedling belt width of 11 cm. Comprehensive analysis revealed that the suitable treatment for Shannong 28 was 25 cm of line spacing with 9 cm of seedling belt width,which could realize the coordination of the three factors of yield composition and get higher yield. Therefore,the reasonable line spacing and seedling belt width were the important technical ways to realize high yield of wheat. 展开更多
关键词 Winter wheat Wide planting Row space form Seedling belt width YIELD
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SLANT IMMERSIONS OF COMPLEX SPACE FORMS AND CHEN'S INEQUALITY 被引量:10
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作者 李光汉 吴传喜 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期223-232,共10页
A submanifold in a complex space form is called slant if it has constant Wirtinger angles. B. Y. Chen and Y. Tazawa proved that there do not exist minimal proper slant surfaces in CP2 and CH2. So it seems that the sla... A submanifold in a complex space form is called slant if it has constant Wirtinger angles. B. Y. Chen and Y. Tazawa proved that there do not exist minimal proper slant surfaces in CP2 and CH2. So it seems that the slant immersion has some interesting properties. The authors have great interest to consider slant immersions satisfying some additional conditions, such as unfull first normal bundles or Chen’s equality holding. They prove that there do not exist n-dimensional Kaehlerian slant immersions in CPn and CHn with unfull first normal bundles. Next, it is seen that every Kaehlerian slant submanifold satisfying an equality of Chen is minimal which is similar to that of Lagrangian immersions. But in contrast, it is shown that a large class of slant immersions do not exist thoroughly. Finally, they give an application of Chen’s inequality to general slant immersions in a complex projective space, which generalizes a result of Chen. 展开更多
关键词 Slant immersion IDEAL Chen's inequality complex space form
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Some Inequalities for Submanifolds in Cosymplectic Space Forms 被引量:1
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作者 LI Xing-xiao HUANG Guang-yue 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第4期372-379,共8页
For submanifolds in a cosymplectic space form tangent to the structure vector field ξ, two important inequalities with Ricci curvature, scalar curvature and the squared mean curvature are obtained. These results are ... For submanifolds in a cosymplectic space form tangent to the structure vector field ξ, two important inequalities with Ricci curvature, scalar curvature and the squared mean curvature are obtained. These results are also applied to get corresponding consequences for anti-invariant submanifolds. 展开更多
关键词 cosymplectic space forms anti-invariant submanifolds
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On Intrinsic Rigidity for Submanifolds with Constant Scalar Curvature in Space Forms 被引量:1
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作者 陈伟 郭震 《Northeastern Mathematical Journal》 CSCD 2007年第3期200-214,共15页
Under the assumption that the normalized mean curvature vector is parallel in the normal bundle, by using the generalized ChengYau's self-adjoint differential operator, here we obtain some rigidity results for compac... Under the assumption that the normalized mean curvature vector is parallel in the normal bundle, by using the generalized ChengYau's self-adjoint differential operator, here we obtain some rigidity results for compact submanifolds with constant scalar curvature and higher codimension in the space forms. 展开更多
关键词 space form scalar curvature differential operator RIGIDITY
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Forming of Space Charge Wave with Broad Frequency Spectrum in Helical Relativistic Two-Stream Electron Beams 被引量:1
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作者 A.Lysenko I.Volk +1 位作者 A.Serozhko O.Rybalko 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期150-154,共5页
We elaborate a quadratic nonlinear theory of plural interactions of growing space charge wave (SCW) harmonics during the development of the two-stream instability in helical relativistic electron beams. It is found ... We elaborate a quadratic nonlinear theory of plural interactions of growing space charge wave (SCW) harmonics during the development of the two-stream instability in helical relativistic electron beams. It is found that in helical two-stream electron beams the growth rate of the two-stream instability increases with the beam entrance angle. An SCW with the broad frequency spectrum, in which higher harmonics have higher amplitudes, forms when the frequency of the first SCW harmonic is much less than the critical frequency of the two-stream instability. For helical electron beams the spectrum expands with the increase of the beam entrance angle. Moreover, we obtain that utilizing helical electron beams in multiharmonic two-stream superheterodyne free-electron lasers leads to the improvement of their amplification characteristics, the frequency spectrum broadening in multiharmonic signal generation mode, and the reduction of the overall system dimensions. 展开更多
关键词 SCW forming of Space Charge Wave with Broad Frequency Spectrum in Helical Relativistic Two-Stream Electron Beams
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HYPERSURFACES IN SPACE FORMS WITH SCALAR CURVATURE CONDITIONS
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作者 徐森林 张运涛 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期39-44,共6页
Let f: Mn(?)Sn+1 C Rn+2 be an n-dimensional complete oriented Rieman-nian manifold minimally immersed in an (n+1)-dimensional unit sphere Sn+1. Denote by S_+~n+1 the upper closed hemisphere. If f(Mn)(?)_+~n+1, then un... Let f: Mn(?)Sn+1 C Rn+2 be an n-dimensional complete oriented Rieman-nian manifold minimally immersed in an (n+1)-dimensional unit sphere Sn+1. Denote by S_+~n+1 the upper closed hemisphere. If f(Mn)(?)_+~n+1, then under some curvature conditions the authors can get that the isometric immersion is a totally embedding. They also generalize a theorem of Li Hai Zhong on hypersurface of space form with costant scalar curvature. 展开更多
关键词 HYPERSURFACE scalar curvature space form
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Ricci Curvature of Certain Submanifolds in Kenmotsu Space Forms
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作者 Liu JIAN-YU LIu XI-MIN 《Communications in Mathematical Research》 CSCD 2009年第4期340-348,共9页
In this paper, we obtain some sharp inequalities between the Ricci cur- vature and the squared mean curvature for bi-slant and semi-slant submanifolds in Kenmotsu space forms. Estimates of the scalar curvature and the... In this paper, we obtain some sharp inequalities between the Ricci cur- vature and the squared mean curvature for bi-slant and semi-slant submanifolds in Kenmotsu space forms. Estimates of the scalar curvature and the k-Ricci curvature, in terms of the squared mean curvature, are also proved respectively. 展开更多
关键词 Kenmotsu space form Ricci curvature k-Ricci curvature bi-slant sub-manifold semi-slant submanifold
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RIGIDITY THEOREMS OF COMPLETE K?HLER-EINSTEIN MANIFOLDS AND COMPLEX SPACE FORMS
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作者 Tian CHONG Yuxin DONG +1 位作者 Hezi LIN Yibin REN 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期339-356,共18页
We concentrate on using the traceless Ricci tensor and the Bochner curvature tensor to study the rigidity problems for complete K?hler manifolds. We derive some elliptic differential inequalities from Weitzenb?ck form... We concentrate on using the traceless Ricci tensor and the Bochner curvature tensor to study the rigidity problems for complete K?hler manifolds. We derive some elliptic differential inequalities from Weitzenb?ck formulas for the traceless Ricci tensor of K?hler manifolds with constant scalar curvature and the Bochner tensor of K?hler-Einstein manifolds respectively. Using elliptic estimates and maximum principle, several L^p and L~∞ pinching results are established to characterize K?hler-Einstein manifolds among K?hler manifolds with constant scalar curvature and complex space forms among K?hler-Einstein manifolds.Our results can be regarded as a complex analogues to the rigidity results for Riemannian manifolds. Moreover, our main results especially establish the rigidity theorems for complete noncompact K?hler manifolds and noncompact K?hler-Einstein manifolds under some pointwise pinching conditions or global integral pinching conditions. To the best of our knowledge,these kinds of results have not been reported. 展开更多
关键词 rigidity theorems Kahler-Einstein complex space forms
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Totally Real Sectional Curvature for Submanifolds in Sasakian Space Forms
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作者 HUANG Guang-yue MA Bing-qing 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期174-178,共5页
By using the methods introduced by Chen[Chen Bang-yen,A series of Ka¨hlerian invarianrts and their applications to Khlerian geometry,Beitrge Algebra Geom,2001,42(1):165-178],we establish some inequalities for... By using the methods introduced by Chen[Chen Bang-yen,A series of Ka¨hlerian invarianrts and their applications to Khlerian geometry,Beitrge Algebra Geom,2001,42(1):165-178],we establish some inequalities for invariant submanifolds in a Sasakian space form involving totally real sectional curvature and the scalar curvature.Moreover,we consider the case of equalities. 展开更多
关键词 Sasakian space forms invariant submanifolds
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<i>L<sup>p</sup>p</i>-Harmonic 1-Forms on <i>δ</i>-Stable Hypersurface in Space Form with Nonnegative Bi-Ricci Curvature
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作者 Bakry Musa Jiancheng Liu 《Advances in Pure Mathematics》 2021年第5期427-439,共13页
In this paper, we investigate the space of <em>L<sup>p</sup> p</em>-harmonic 1-forms on a complete noncompact orientable <em>δ</em>-stable hypersurface <em>M<sup>m</... In this paper, we investigate the space of <em>L<sup>p</sup> p</em>-harmonic 1-forms on a complete noncompact orientable <em>δ</em>-stable hypersurface <em>M<sup>m</sup></em> that is immersed in space form <img src="Edit_6fbc11b9-ac23-40e2-b045-0fb25419337d.png" width="35" height="23" alt="" /> with nonnegative BiRic curvature. We prove the nonexistence of <em>L<sup>p</sup> p</em>-harmonic 1-forms on <em>M<sup>m</sup></em>. Moreover, we obtain some vanishing properties for this class of harmonic 1-forms. 展开更多
关键词 Lp p-Harmonic 1-forms δ-Stable Hypersurface BiRic Curvature Space form
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Generic Existence of Infinitely Many Non-contractible Closed Geodesics on Compact Space Forms
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作者 Hui Liu Yu Chen Wang 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第7期1674-1684,共11页
Let M=S^(n)/Γand h be a nontrivial element of finite order p inπ_(1)(Μ),where the integers n,p≥2,Γis a finite abelian group which acts freely and isometrically on the n-sphere and therefore M is diffeomorphic to ... Let M=S^(n)/Γand h be a nontrivial element of finite order p inπ_(1)(Μ),where the integers n,p≥2,Γis a finite abelian group which acts freely and isometrically on the n-sphere and therefore M is diffeomorphic to a compact space form.In this paper,we prove that there are infinitely many non-contractible closed geodesics of class[h]on the compact space form with C^(r)-generic Finsler metrics,where 4≤r≤∞.The conclusion also holds for Cr-generic Riemannian metrics for 2≤r≤∞.The proof is based on the resonance identity of non-contractible closed geodesics on compact space forms. 展开更多
关键词 Compact space forms non-contractible closed geodesics generic Finsler metrics resonance identity
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ON THE INVARIANT SUBMANIFOLDS OF RIEMANNIAN PRODUCT MANIFOLD
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作者 M.Atceken S.Keles 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期549-558,共10页
In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finall... In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finally, necessary and sufficient conditions are given on an invariant submanifold of a Riemannian product manifold to be a locally symmetric and real space form. 展开更多
关键词 Riemannian product manifold mixed geodesic submanifold real space form and almost Riemannian product structure
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Perfect Combination of Architectural Functions and Flow Lines: Study on Roof Garden of Frank Gehry's Walt Disney Concert Hall
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作者 WANG Haiou 《Journal of Landscape Research》 2016年第2期21-22,26,共3页
By exploring the space and the design techniques of roof garden in Frank Gehry's Walt Disney Concert Hall, this paper made further research on the combination of architectural functions and pedestrian fl ow lines,... By exploring the space and the design techniques of roof garden in Frank Gehry's Walt Disney Concert Hall, this paper made further research on the combination of architectural functions and pedestrian fl ow lines, and attempted to summarize the unique design techniques of Frank Gehry by analyzing his works, improve and develop design theories of roof garden, and attract more attention from the public to roof garden design. 展开更多
关键词 Walt Disney Concert Hall Roof garden Space form FUNCTION Flow lines
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Study on the Integration and Optimization of Campus Spaces: A Case Study of Yaohu Campus of Jiangxi Normal University
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作者 LI Xiaoyun DING Yilei 《Journal of Landscape Research》 2015年第2期1-2,5,共3页
In view of the problems brought by blind expansion of campus, such as lack of public spaces, oversized spaces, and improper traffic designs, this paper took Yaohu Campus of Jiangxi Normal University for example, propo... In view of the problems brought by blind expansion of campus, such as lack of public spaces, oversized spaces, and improper traffic designs, this paper took Yaohu Campus of Jiangxi Normal University for example, proposed the methods for integrating and optimizing campus spaces, such as establishing artistic conception of campus space, improving campus traffic organization, creating and improving the external communication spaces, on the basis of analyzing evolution history of campus spaces. 展开更多
关键词 UNIVERSITY Campus space form INTEGRATION Optimization
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C-Totally Real Submanifolds with Parallel Mean Curvature Vector of Sasakian Space Form
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作者 宣满友 刘继志 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2002年第4期545-548,共4页
We have discussed the C-totally real subrnanifolds with parallel mean curvature vector of Sasakian space form, obtained a formula of J.Simons type, and improved one result of S.Yamaguchi.
关键词 Sasakian space form parallel mean curvature vector C-totally real sub-manifold.
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Rigidity Theorems for Hypersurfaces in Real Space Form
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作者 潮小李 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第3期367-370,共4页
In this paper, a rigidity theorem of hypersurface in real space form will be given. In addition, we obtain rigidity theorems of submanifold in sphere which improve the result of Hou and Xu.
关键词 HYPERSURFACE real space form rigidity.
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2-Harmonic Submanifolds in a Complex Space Form 被引量:12
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作者 ZHU Ye Cheng SONG Wei Dong 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第3期727-732,共6页
In the present paper,the authors study totally real 2-harmonic submanifolds in a complex space form and obtain a Simons' type integral inequality of compact submanifolds as well as some relevant conclusions.
关键词 2-HARMONIC MINIMAL totally geodesic complex space form.
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On the Mean Absolute Geodesic Curvature of Closed Curves in 2-Dimensional Space Forms 被引量:7
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作者 YouNingWANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第4期757-764,共8页
In this paper, we establish some formulas on closed curves in 2-dimensionalspace forms. Mean absolute geodesic curvature is introduced to describe the average curving of aclosed curve. In this sense, a closed curve co... In this paper, we establish some formulas on closed curves in 2-dimensionalspace forms. Mean absolute geodesic curvature is introduced to describe the average curving of aclosed curve. In this sense, a closed curve could be compared with a geodesic circle that is theboundary of a convex geodesic circular disk containing the closed curve. The comparison can be usedto show some properties of space forms only on themselves. 展开更多
关键词 closed curve space forms mean absolute geodesic curvature
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Time-Like Conformal Homogeneous Hypersurfaces with Three Distinct Principal Curvatures 被引量:3
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作者 Yanbin LIN Ying LU Changping WANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2020年第5期679-696,共18页
A hypersurface x(M)in Lorentzian space R41 is called conformal homogeneous,if for any two points p,q on M,there exists,a conformal transformation of R41,such that(x(M))=x(M),(x(p))=x(q).In this paper,the authors gi... A hypersurface x(M)in Lorentzian space R41 is called conformal homogeneous,if for any two points p,q on M,there exists,a conformal transformation of R41,such that(x(M))=x(M),(x(p))=x(q).In this paper,the authors give a complete classifica-tion for regular time-like conformal homogeneous hypersurfaces in R41 with three distinct principal curvatures. 展开更多
关键词 Lorentzian metric Conformal metric Conformal space form Conformal homogeneous Time-like hypersurface
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Isometric Spacelike Immersions of Space Forms in Indefinite Space Forms 被引量:1
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作者 李海中 吴岚 《Tsinghua Science and Technology》 SCIE EI CAS 2001年第4期344-346,共3页
Let M be a connected n dimensional space form spacelike isometrically immersed in a (2n-1) dimensional indefinite space form. If M is maximal, we prove that either M is totally geodesic or M is a piece of the n ... Let M be a connected n dimensional space form spacelike isometrically immersed in a (2n-1) dimensional indefinite space form. If M is maximal, we prove that either M is totally geodesic or M is a piece of the n dimensional hyperbolic cylinder in the (2n-1) dimensional pseudo hyperbolic space. 展开更多
关键词 space form indefinite space form spacelike MAXIMAL
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