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小麦抗条锈基因Yr5、Yr9和Yr18分子标记的特异性评估

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麦类作物学报 2025年第1期45卷 45-51页

作者：孙振宇黄亮黄苗苗刘太国甘肃省农业科学院植物保护研究所甘肃兰州730070 中国农业科学院植物保护研究所植物病虫害综合治理全国重点实验室北京100193 青海大学农林科学院青海西宁810016

Yr5、Yr9(1B/1R)、Yr18基因的自身性状或连锁性状在中国小麦育种中具有重要的应用前景。本研究运用以Avocet S为背景的单基因近等基因系及其对应基因的载体品种,对Yr5基因的连锁标记STS9/10,Yr9(1B/1R)基因的分子标记AF1/4、D15、20H,Y... 详细信息

Yr5、Yr9(1B/1R)、Yr18基因的自身性状或连锁性状在中国小麦育种中具有重要的应用前景。本研究运用以Avocet S为背景的单基因近等基因系及其对应基因的载体品种,对Yr5基因的连锁标记STS9/10,Yr9(1B/1R)基因的分子标记AF1/4、D15、20H,Yr18基因的分子标记csLV34、cssfr1~cssfr5进行有效性验证。结果表明,Yr5基因的特异性分子标记STS9/10、Yr9(1B/1R)基因的特异性分子标记AF1/4、D15和20H均能够准确识别不同遗传背景材料中的相应抗性基因;Yr18基因分子标记cssfr2能够准确检测Yr18的非载体材料,并检测出Avocet S*6/Yr5、Avocet S*6/Yr24、Avocet S*6/Yr27三个材料具有Yr18的等位变异。这说明Yr5基因的连锁标记STS9/10,Yr9(1B/1R)基因的分子标记AF1/4、D15、20H能对目的基因进行有效检测,Yr18基因的几个分子标记结合使用不仅能够对目的基因进行有效检测,而且能够识别该位点的等位变异。

关键词：抗条锈基因分子标记特异性

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Effects of Length Scales on Equilibrium Domains in Superelastic NiTi Tubes Helix Versus Cylinder

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Effects of Length Scales on Equilibrium Domains in Superelas...

EDGE-ORIENTED HEXAGONAL ELEMENTS

The 16th Annual Conference of Hong Kong Society of Theoretical and Applied Mechanics 2012、The 1st Mainland-Hong Kong Youth Forum on Mechanics 2012、The 8th Shanghai-Hong Kong Forum on Mechanics and Its Application 2012

作者： L.Dong q.P.sun Department of Mechanical Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina

Macroscopic cylinder- and helix-shaped deformation domains were observed in NiTi polycrystalline shape memory alloy tubes during the phase transition under uniaxial quasi-static isothermal *** experiments showed that the occurrence of cylinder or helix domain and its subsequent isothermal evolution strongly depend on the domain volume,tube wall-thickness and loading *** paper studies the energetics of the cylindrical and helical domains using an elastic inclusion *** is demonstrated that the total misfit strain energy of an equilibrium domain in tube essentially depends on two nondimensional length scales:the normalized effective domain length and the normalized *** on such understanding,we quantify the length scale dependence in the energy of the equilibrium cylindrical and helical *** energetic preference of each type of domain is predicted and the critical condition for the helix→cylinder domain transition is established.

关键词： Effects of Length Scales on Equilibrium Domains in Superelastic NiTi Tubes Helix Versus Cylinder

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Journal of Computational Mathematics 2007年第4期25卷 430-439页

作者： Chao Yang Jiachang sun Parallel Computing Lab. Institute of Software Chinese Academy of Sciences Beijing 100080 China

In this paper, two new nonconforming hexagonal elements are presented, which are based on the trilinear function space q1^（3） and are edge-oriented, analogical to the case of the rotated q1 quadrilateral element. A priori error estimates are given to show that the new elements achieve first-order accuracy in the energy norm and second-order accuracy in the L^2 norm. This theoretical result is confirmed by the numerical tests.

关键词： Nonconforming finite element method Hexagonal element q1 element.

Macroscopic and microscopic mechanical behaviors of climbing tendrils

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Acta Mechanica Sinica 2019年第3期35卷 702-710页

作者： q.Guo J.J.Dong Y.Liu X.H.Xu q.H.qin J.S.Wang Tianjin Key Laboratory of Modern Engineering Mechanics Department of MechanicsTianjin UniversityTianjin 300054China State Key Laboratory of Nonlinear Mechanics (LNM) Institute of MechanicsChinese Academy of ScienceBeijing 100080China Research School of Engineering Australian National UniversityCanberraACT 2601Australia

Tendril-bearing climbing plants must recur to the tendril helices with chiral perversion or dual chirality for climbing and to obtain sun exposure. Despite researchers' prolonged fascination with climbing tendrils since Darwin's time and even earlier, why the soft and slender tendrils can bear heavy loads such as the self-weight of a plant or additional load caused by rain remains elusive. In this paper, we take towel gourd tendrils as an example and investigate the macroscopic and microscopic mechanical behaviors of tendrils through experiments and simulations. Our study indicates that the tendril filament exhibits rubber-like hyperelastic behaviors and can particularly endure large elongation, which is mainly attributed to the superelasticity of the cellulose fibril helix contained in the cell wall. Combination of the tendril helical structure with dual chirality or chiral perversion at a macroscale and a cellulose filament helix at a subcellular level creates superior elasticity for biological species relying on support and climbing. This study provides deep insight into the structure-property relationship of climbing tendrils, and the relationship is useful for the bioinspired design of composite systems with superior elasticity.

关键词： Climbing tendril Mechanical behaviors Structure-property relationship Large elongation

Light-tailed behavior of stationary distribution for state-dependent random walks on a strip

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Frontiers of Mathematics in China 2014年第4期9卷 813-834页

作者： Wenming HONG Meijuan ZHANG Yiqiang q. ZHAO School of Mathematical Sciences & Laboratory of Mathematics and Complex Systems Beijing Normal University Beijing 100875 China School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081 China School of Mathematics and Statistics Carleton University Ottawa Ont K1S 5B6 Canada

We consider the state-dependent reflecting random walk on a half- strip. We provide explicit criteria for （positive） recurrence, and an explicit expression for the stationary distribution. As a consequence, the light-tailed behavior of the stationary distribution is proved under appropriate conditions. The key idea of the method employed here is the decomposition of the trajectory of the random walk and the main tool is the intrinsic branching structure buried in the random walk on a strip, which is different from the matrix-analytic method.

关键词： Random walk on a strip stationary distribution light-tailedbehavior branching process recurrence state-dependent

Corotational nonlinear analyses of laminated shell structures using a 4-node quadrilateral flat shell element with drilling stiffness

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Acta Mechanica Sinica 2014年第3期30卷 418-429页

作者： Zhen Wang qin sun School of Aeronautics Northwestern Polytechnical University

A new 4-node quadrilateral flat shell element is developed for geometrically nonlinear analyses of thin and moderately thick laminated shell structures. The fiat shell element is constructed by combining a quadrilateral area co- ordinate method （qAC） based membrane element AGq6- II, and a Timoshenko beam function （TBF） method based shear deformable plate bending element ARS-q12. In order to model folded plates and connect with beam elements, the drilling stiffness is added to the element stiffness matrix based on the mixed variational principle. The transverse shear rigidity matrix, based on the first-order shear deformation theory （FSDT）, for the laminated composite plate is evaluated using the transverse equilibrium conditions, while the shear correction factors are not needed. The conventional TBF methods are also modified to efficiently calculate the element stiffness for laminate. The new shell element is extended to large deflection and post-buckling analyses of isotropic and laminated composite shells based on the element independent corotational formulation. Numerical re- sults show that the present shell element has an excellent numerical performance for the test examples, and is applicable to stiffened plates.

关键词： Geometrically nonlinear. quadrilateral area co-ordinate method Timoshenko beam function Laminatedcomposite Drilling degree of freedom ~ Corotational for-mulation

Solid solution strengthening of high-entropy alloys from first-principles study

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Journal of Materials Science & Technology 2022年第26期121卷 105-116页

作者： H.L.Zhang D.D.Cai X.sun H.Huang S.Lu Y.Z.Wang q.M.Hu L.Vitos X.D.Ding State Key Laboratory for Mechanical Behavior of Materials Frontier Institute of Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research College of StomatologyXi’an Jiaotong UniversityXi’an 710049China Department of Materials Science and Engineering The Ohio State University2041 College RoadColumbusOH 43210United States Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China Applied Materials Physics Department of Materials Science and EngineeringRoyal Institute of TechnologyStockholm SE-10044Sweden

Solid solution strengthening(SSS)is one kind of strengthening mechanisms and plays an important role in alloy design,in particular for single-phase alloys including high-entropy alloys(HEAs).The classical Labusch–Nabarro model and its expansions are most widely applicable to treating SSS of solid solution alloys including both conventional alloys(CAs)and *** this study,the SSS effects in a series of Febased CAs and HEAs are investigated by using the classical Labusch–Nabarro model and its *** size misfit and shear modulus misfit parameters are derived from first-principles *** on available experimental data in combination with empirical SSS model,we propose fitting constants(i.e.,the ratio between experimental hardness and predicted SSS effect)for these two families of *** predicted host/alloy family-dependent fitting constants can be used to estimate the hardness of these SSS *** agreement between predicted and measured hardness values is satisfactory for both CAs and HEAs,implying that the proposed approach is reliable and successful.

关键词： Alloys Solid solution strengthening Hardness Size misfit parameter Shear modulus misfit parameter First-principles calculations

EFFECTS OF HDDR PROCESS ON STRUCTURE AND MAGNETIC PROPERTIES OF Nd(Fe,Ti)_(12)N_δ PREPARED BY MECHANICAL ALLOYING

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 68-78页

作者： B.ZCui X.K.sun X.G.Zhao W.Liu q.F.Xiao T.Zhao Z.D.Zhang Y.C.Sui Chinese Acad of Sciences Shenyang China

The effects of the hydrogenation-disproportionation-desorption-recombination (HDDR) process on the structure and the magnetic properties of the mechanical alloying (MA) prepared Nd8Fe84 Ti8 alloy and its nitride counterpart have been studied in detail. It has been found that Nd(Fe, Ti)12Hδ is formed in the temperature range from 300 to 550°℃. The disproportionation is ready to start at 550°℃ and is complete at 960°℃.The desorption and the recombination are almost synchronized. The phase of Nd(Fe,Ti)7 is formed at 750°℃ during the HDDR treatment. With increasing temperature of HDDR process, the metastable structure of TbCu7 type is gradually transformed into the structure of ThMn12 type. The intrinsic coercivity and the maximum magnetic energy product increase with increasing temperature of HDDR process.

关键词： Nd(Fe Ti)_(12)N_δ compound,magnetic property hydrogenation

Further results on Hilbert’s Tenth Problem

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Science China Mathematics 2021年第2期64卷 281-306页

作者： Zhi-Wei sun Department of Mathematics Nanjing UniversityNanjing 210093China

Hilbert’s Tenth Problem(HTP)asks for an algorithm to test whether an arbitrary polynomial Diophantine equation with integer coefficients has solutions over the ring Z of *** was finally solved negatively by Matiyasevich in *** this paper we obtain some further results on HTP over *** prove that there is no algorithm to determine for any P(z1,...,z9)∈Z[z1,...,z9]whether the equation P(z1,...,z9)=0 has integral solutions with z9≥***,there is no algorithm to test whether an arbitrary polynomial Diophantine equation P(z1,...,z11)=0(with integer coefficients)in 11 unknowns has integral solutions,which provides the best record on the original HTP over *** also prove that there is no algorithm to test for any P(z1,...,z17)∈Z[z1,...,z17]whether P(z12,...,z172)=0 has integral solutions,and that there is a polynomial q(z1,...,z20)∈Z[z1,...,z20]such that{q(z12,...,z202):z1,...,z20∈Z}∩{0,1,2,...}coincides with the set of all primes.

关键词： Hilbert’s Tenth Problem Diophantine equation integral solution undecidability polygonal numbers