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Plant biotic interactions: From fundamental research toward sustainable agriculture

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Journal of Integrative Plant Biology 2021年第2期63卷 275-276页

作者： Rosa Lozano-Duran Suomeng dong Sh.nghai Center for Plant Stress Biology CAS Center for Excellence in Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai 201602China Department of Plant Biochemistry Centre for Plant Molecular Biology(ZMBP)Eberhard Karls UniversityD-72076 TubingenGermany The Key Laboratory of Plant Immunity and Department of Plant Pathology Nanjing Agricultural UniversityNanjing 210095China

Plants not only provide food and natural materials for humankind, but also constitute an indispensable part of the ecological system of this planet:without plants, life as we know it would simply not be possible. Through their lifespans,plants interact with a plethora of other organisms, including beneficial microbes and potential pathogens. Dissecting the underlying mech.nisms determining the outcome of plant biotic interactions is a cornerstone for the design of rational management strategies to secure global food production and ecological balance.

关键词： corners planet rational

Preparation and Microstructure Analysis of high Strength Cementitious Materials Containing Metakaolin

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武汉理工大学学报 2010年第17期32卷 117-122,136页

作者： YU R ShUI Z h dong J School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The preparation and microstructure analysis of high strength cementitious materials containing metakaolin (MK) was studied in this paper. The MK was prepared firstly,and th.n was mixed with fly ash,ground blast furnace slag,quartz powder and cement with different percentage to produce high strength cementitious materials. After cured under different environment,the compressive strength of such materials was tested. Techniques of X-ray diffraction (XRD) and scanning electron microscopy (SEM) were further employed to identify the composition and microstructure. The results obtained reveal that the compressive strength of such materials mainly effected by component of raw materials,the water binder ratio (W/B) and the curing regime. Wh.n the three factors above are optimized,the compressive strength of such materials can get to 156 MPa in maximum. The X-ray diffraction analysis and the scanning electron microscopic images indicated that under optimal curing condition,more raw materials can take chemical reaction and the microstructure is dense to yield good mech.nical properties.

关键词： preparation microstructure analysis high strength cementitious materials metakaolin

Weakly Singular Symmetric Galerkin Boundary Element Method for Fracture Analysis of Three-Dimensional Structures Considering Rotational Inertia and Gravitational Forces

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1857-1882页

作者： Shuangxin he Chaoyang Wang Xuan Zhou Leiting dong Satya n.Atluri School of Aeronautic Science and Engineering Beihang UniversityBeijingChina Department of Mech.nical Engineering Texas Tech UniversityLubbockUSA

The Symmetric Galerkin Boundary Element Method is advantageous for the linear elastic fracture and crackgrowth analysis of solid structures,because only boundary and crack-surface elements are ***,for engineering structures subjected to body forces such as rotational inertia and gravitational loads,additional domain integral terms in the Galerkin boundary integral equation will necessitate mesh.ng of the interior of the *** this study,weakly-singular SGBEM for fracture analysis of three-dimensional structures considering rotational inertia and gravitational forces are *** using divergence theorem or alternatively the radial integration method,the domain integral terms caused by body forces are transformed into boundary *** due to the weak singularity of the formulated boundary integral equations,a simple Gauss-Legendre quadrature with a few integral points is sufficient for numerically evaluating the SGBEM *** numerical examples are presented to verify this approach and results are compared with benchmark solutions.

关键词： Symmetric Galerkin boundary element method rotational inertia gravitational force weak singularity stress intensity factor

numerical Analysis of MhD Accelerator with.non-Equilibrium Air Plasma

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Plasma Science and Technology 2012年第12期14卷 1110-1115页

作者： M.AnWARI h.h.QAZI SUKARSAn n.hARADA Electrical Engineering Department Umm Al-Qura University Faculty of Electrical Engineering Universiti Teknologi Malaysia Faculty of Electrical Engineering Universitas Islam "45" Bekasi Department of Electrical Engineering Nagaoka University of Technology

Magnetohydrodynamic （MhD） accelerator is proposed as a next generation propulsion system. It can be used to increase the performance of a propulsion system. The objective of this study is to investigate the performance of MhD accelerator using non-equilibrium air plasma as working gas. In this study, the fundamental performance of MhD accelerator such as flow performance and electrical performance is evaluated at different levels of applied magnetic field using I-D numerical simulation. The numerical simulation is developed based on a set of differential equations with MhD approximation. To solve this set of differential equations the MacCormack scheme is used. A specified ch.nnel designed and developed at nASA Marshall Space Flight Centre is used in the numerical simulation. The composition of the simulated air plasma consists of seven species, namely, n2, n, O2, O, nO, nO＋, and e-. The performance of the non-equilibrium MhD accelerator is also compared with the equilibrium MhD accelerator.

关键词： MhD accelerator Faraday type connection non-equilibrium air plasma

Composition and size dependent torsion fracture of metallic glasses

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Journal of Materials Science & Technology 2021年第23期82卷 153-160页

作者： J.dong J.Sh.n Y.h.Sun h.B.Ke B.A.Sun W.h.Wang h.Y.Bai Institute of Physics Chinese Academy of SciencesBeijing100190PR China College of Materials Science and Opto Electronic Technology University of Chinese Academy of SciencesBeijing100049PR China Songsh.n Lake Materials Laboratory DongguanGuangdong523808PR China

The fracture of metallic glasses(MGs)of different compositions and sizes down to micrometers under torsion loading were systematically *** to the flat shear fracture along the circumferential plane as commonly supposed under torsion,we find that the torsion fracture of metallic glasses can deviate from flat shear plane,and the fracture angle is closely dependent on the composition and the size of MG *** a conversion method,we show that the torsion fracture of both millimeterand micrometer-sized MGs can be described by the ellipse fracture criterion as originally proposed for the tension *** deviation from the circumferential shear plane under torsion is further shown to intrinsically relate to the fracture toughness of *** tougher MG tends to have a smaller fracture angle with respect to the maximum shear plane,and vice versa,indicating a correlation between the fracture toughness and pressure/normal stress sensitivity in *** results provide new insights on the fracture mech.nism and are helpful to design and control the deformation and fracture behavior of MGs under torsion loading.

关键词： Metallic glasses Torsion fracture Pressure sensitivity Fracture toughness

Scattering of Tollmien-Schlichting waves by localized roughness in transonic boundary layers

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Applied Mathematics and Mech.nics(English Edition) 2020年第7期41卷 1105-1124页

作者： Ming dong Department of Mech.nics Tianjin UniversityTianjin 300072China Laboratory for high-Speed Aerodynamics Tianjin UniversityTianjin 300072China

The laminar-turbulent transition in boundary-layer flows is often affected by wall imperfections, because the latter may interact with either the freestream perturbations or the oncoming boundary-layer instability modes, leading to a modification of the accumulation of the normal modes. The present paper particularly focuses on the latter mech.nism in a transonic boundary layer, namely, the effect of a two-dimensional(2 D) roughness element on the oncoming Tollmien-Schlichting(T-S) modes wh.n they propagate through the region of the rapid mean-flow distortion induced by the roughness. The wave scattering is analyzed by adapting the local scattering theory developed for subsonic boundary layers(WU, X. S. and dong, M. A local scattering theory for the effects of isolated roughness on boundary-layer instability and transition: transmission coefficient as an eigenvalue. Journal of Fluid Mech.nics, 794, 68–108(2006)) to the transonic regime, and a transmission coefficient is introduced to characterize the effect of the roughness. In the sub-transonic regime, in which the Mach.number is close to, but less th.n, 1, the scattering system reduces to an eigenvalue problem with the transmission coefficient being the eigenvalue;while in the super-transonic regime, in which the Mach.number is slightly greater th.n 1, the scattering system becomes a high-dimensional group of linear equations with the transmission coefficient being solved afterward. In the largeReynolds-number asymptotic theory, the K′arm′an-Guderley parameter is introduced to quantify the effect of the Mach.number. A systematical parametric study is carried out,and the dependence of the transmission coefficient on the roughness shape, the frequency of the oncoming mode, and the K′arm′an-Guderley parameter is provided.

关键词： boundary layer scattering instability Tollmien-Schlichting(T-S)wave triple deck

A new Pregnane Glycoside from Dioscorea collettii var. hypoglauca

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Ch.nese Chemical Letters 1998年第8期9卷 739-742页

作者： hu, K dong, AJ Kobayashi, h Iwasaki, S Yao, XS Sh.nyang Pharmaceut Univ Dept Nat Prod Chem Shenyang 110015 Peoples R China nE Pharmaceut Co Inst Drug Res & Dev Shenyang 110026 Peoples R China Univ Tokyo Inst Mol & Cellular Biosci Tokyo 113 Japan

A new pregnane glycoside hypoglaucin G was isolated from Dioscorea collettii var. hypoglauca by bioactivity-guided fractionation, which showed a moderate activity of inducing morphological deformation of the Pyricularia oryzae mycelia. The structure of hypoglaucin G was established as 16 beta-(4'-methyl-5'-O-beta-D-glucopyranosyl-pentanoyloxy)-pregn-5-en-3 beta-ol-20-one 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)-]-beta-D-glucopyranoside by chemical evidence and spectral analysis, especially by 2D-nMR techniques.

关键词： hypoglaucin G Dioscorea collettii var. hypoglauca Pyricularia oryzae

ThE BAnACh ALGEBRAS GEnERATED BY OPERATORS WITh OnE-POInT SPECTRUM

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Acta Mathematica Scientia 2011年第2期31卷 673-680页

作者： h. Seferoglu n. Simsek Department of Mathematics Faculty of Sciences Yuzuncu Yil University Department of Mathematics Faculty of Arts and Sciences Istanbul Commerce University

In this article, we present some results related to the structure of Banach algebras generated by operators with one-point spectrum.

关键词： Representation group spectrum Banach algebra group algebra

Lithofacies architecture and palaeogeography of the Late Paleozoic glaciomarine Talchir Formation,Raniganj Basin,India

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Journal of Palaeogeography 2015年第3期4卷 269-283页

作者： h.n.Bhattacharya Biplab Bhattacharya Department of Geology Presidency University Department of Earth Sciences Indian Institute of Technology

Talchir Formation （Permo-Carboniferous） of the Gondwana Supergroup records the Late Paleozoic glaciation in Peninsular India. Talchir sedimentary succession of the Raniganj Basin, Damodar Valley Coalfields, Peninsular India, bears ten facies types grouped under three facies associations, viz., the proglacial conglomerate-sandstone facies association （CS）, the foreshore-shoreface conglomerate-sandstone-mudstone facies association （CSM） and the prodelta-shelf sandstone-mudstone facies association （SM）. Overall facies architecture reflects initial ice-covered terrestrial subgiacial sedimentation, which was subsequently reworked and emplaced subaqueously in front of the ice-grounding line, and finally overlapped by storm-laid prodelta-shelf sediments. Repeated glacial advance-retreats with shifts in the position of the ice-grounding line during phases of climatic amelioration led to multiple deglaciation-related fining-up cycles. Decoupled ice sheet and floating icebergs contributed icerafted debris （IRD） to these sediments. Gradual retreat of the ice sheet, however, restricted the supply of IRD towards top of the succession. Overlap of wave-agitated shoreface-shelf sediments on the glaciogenic sediments indicates widespread marine transgression caused by glacier melting during ice-house to green-house climatic transition, and crustal downsagging related to giacioisostasy. Subsequently, complete disappearance of the ice sheet caused basinal exhumation along with crustal uplift due to isostatic rebound, leading to multiple horst-graben bounded basinal systems, which received post-Talchir coal-bearing Gondwana sediments.

关键词： Late Pateozoic Tatchir Formation Ranganj Basin giaciornarine sedimen-tation facies architecture sequence stratigraphy