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Wild Brassica and Its Close Relatives in Turkey,the Genetic Treasures

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Horticultural Plant Journal 2021年第2期7卷 97-107页

作者： Ali A.Donmez Zubeyde Ugurlu Aydın xiaowu Wang Molecular Plant Systematic Laboratory(MOBIS) Department of BiologyFaculty of ScienceHacettepe UniversityAnkara 06800Turkey Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture Sino-Dutch Joint Laboratory of Horticultural GenomicsInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing 100081China

Brassica taxa occur naturally and are also cultivated in *** to their economic importance,several cultivars have been extensively cultivated in certain regions of the *** extensive cultivation for vegetable production of the other species of the genus,Brassica juncea has very limited *** native species of Brassica are known from restricted locations in Turkey with only a few *** them,Brassica elongata is distributed all over the Central and Eastern parts of the country and it prefers unfertile soils on *** the current data about the Brassica taxa would lead to new initiatives for Brassica research dealing with both the genetic structure and the origin of the *** characters of the genera closely related to Brassica have been discussed under the relevant ***,an overview for the Turkish Brassiceae tribe,both native and cultivated,has been presented and the relevant identification keys have been supplied for updating.

关键词： Brassica Brassiceae cultivation native Turkey

Anisotropic Mech.nical Response of nacre to Heat Treatment Under Indentation:Effect of Structural Orientation

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Journal of Bionic Engineering 2024年第3期21卷 1453-1464页

作者： Simin Liang Yingying Li Hongmei Ji xiaowu Li Department of Materials Physics and chemistry School of Materials Science and EngineeringKey Laboratory for Anisotropy and Texture of MaterialsMinistry of EducationNortheastern UniversityShenyang110819China

It is generally considered that heat treatments have a negative impact on the mech.nical properties of nacre due to thermal decomposition of the organic ***,the present work investigated the microindentation behavior on fresh and heat-treated nacres from two orthogonal directions,and the results demonstrate that both hardness value and damage tolerance can remain almost unch.nged on the cross-section with the organic matrix degeneration,despite a significant deterioration on the platelet *** analyses suggest that the anisotropic response of indentation behavior to heat treatment in nacre is primarily caused by its structural ***,compared with a single layer of irregular interplatelet interfaces in cross-sectional specimens,the multiple layers of parallel interlamellar interfaces in in-plane specimens exhibit a much greater ability to impede indenter-triggered destruction,and heat treatments would reduce the in-plane hardness but nearly have no effect on the cross-sectional ***,the deeper embedding of platelets in cross-sectional specimens enhances their resistance to interface cracking caused by organic matrix degradation at high temperatures,leading to a reduced sensitivity to ***,the indentation behavior of nacre shows different tendencies in response to variations in the organic matrix state along normal and parallel directions.

关键词： nacre Structural orientation Heat treatment Indentation behavior Organic matrix

Diffusive transport of two charge equivalent and structurally similar ruthenium complex ions through graphene oxide membranes

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nano Research 2015年第4期8卷 1128-1138页

作者： Michael Coleman xiaowu (Shirley) Tang Department of chemistry 200 University Ave West Waterloo Ontario N2L 3G1 Canada Waterloo Institute for nanotechnology 200 University Ave West Waterloo Ontario N2L 3G 1 Canada

Here, we report a study of ion transport across graphene oxide （GO） membranes of various thicknesses, made by vacuum filtration of GO aqueous solutions. The diffusive transport rates of two charge-equivalent ruthenium complex ions Ru（bpy）3^2＋ and Ru（phen）32% with a sub-angstrom size difference, are distinguishable through GO membranes and their ratio can be a unique tool for probing the transport-relevant pore structures. Pore and slit-dominant hindered diffusion models are presented and correlated to experimental results. Our analysis suggests that ion transport is mostly facilitated by large pores （larger than 1.75 nm in diameter） in the relatively thin GO membranes, while slits formed by GO stacking （less than 1.42 nm in width） become dominant only in thick membranes. By grafting PEG molecules to the lateral plane of GO sheets, membranes with enlarged interlayer spacing were engineered, which showed drastically increased ion transport rates and lower distinction among the two ruthenium complex ions, consistent with the prediction by the slit-dominant steric hindered diffusion model.

关键词： graphene oxide ion transport hindered diffusion nanofluidics

Improving Fatigue Properties of 316L Stainless Steel Welded Joints by Surface Spinning Strengthening

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 840-854页

作者： Dongqiqiong Wang Qiang Wang xiaowu Li Zhefeng Zhang Department of Materials Physics and chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shi-ch.ngxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China College of Light Industry Liaoning UniversityShenyang 110036China

The surface spinning strengthening(3S)mech.nism and fatigue life extension mech.nism of 316L stainless steel welded joint were systematically elucidated by microstructural analyses and mech.nical *** indicate that surface gradient hardening layer of approximately 1 mm is formed in the base material through grain fragmentation and deformation twin strengthening,as well as in the welding zone composed of deformedδ-phases and *** fatigue strength of welded joint after 3S significantly rises by 32%(from 190 to 250 MPa),which is attributed to the effective elimination of surface geometric defects,discrete refinement ofδ-Fe phases and the appropriate improvement in the surface strength,collectively mitigating strain localization and surface fatigue damage within the gradient strengthening *** redistributed fineδ-Fe phases benefited by strong stress transfer of 3S reduce the risk of surface weak phase cracking,causing the fatigue fracture to transition from microstructure defects to crystal defects dominated by slip,further suppressing the initiation and early propagation of fatigue cracks.

关键词： 316L stainless steel Welded joint Surface spinning strengthening nanotwin Fatigue life

Microstructural characterization and Hardness Behavior of a Biological Saxidomus purpuratus Shell

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Journal of Materials Science & Technology 2011年第2期27卷 139-146页

作者： Wen Yang Guangping Zhang Huasai Liu xiaowu Li Institute of Materials Physics and chemistry College of SciencesNortheastern UniversityShenyang 110004China Shenyang national Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110004China

The microstructures of the Saxidomus purpuratus shell were *** was found that the inner and middle layers of the shell are composed of crossed lamellae,while the outer layer exhibits porous *** the characteristic structure of each layer,the hardness of inner layer with narrow domains in crossed lamellar structure is the highest,and that of middle layer with wide domains is lower,while the outer layer has the lowest *** damage morphologies of the indentations ch.nge a lot,depending not only upon the magnitude of the indentation load,but also upon the orientation between the indentation direction and the crossed lamellae in the microstructure of the shell,which illustrates the anisotropy in mech.nical properties of such shells.

关键词： Saxidomus purpuratus shell Microstructure Hardness Crossed lamellar Indentation

Genome triplication drove the diversification of Brassica plants

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Horticulture Research 2014年第1期1卷 190-197页

作者： Feng ch.ng Jian Wu xiaowu Wang Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesBeijing 100081China

The genus Brassica belongs to the plant family Brassicaceae,which includes many important crop species that are used as oilseed,condiments,or vegetables throughout the *** plants comprise many diverse species,and each species contains rich morphotypes showing extreme *** species experienced an extra whole genome triplication(WGT)event compared with the model plant Arabidopsis *** genome sequencing of the Brassica species Brassica rapa,Brassica oleracea and others demonstrated that WGT plays an important role in the speciation and morphotype diversification of Brassica *** genomic analysis based on the genome sequences of *** and *** clearly identified the WGT event and further demonstrated that the translocated Proto-Calepine Karyotype(tPCK,n57)was the diploid ancestor of the three subgenomes in *** WGT,subsequent extensive genome fractionation,block reshuffling and chromosome reduction accompanied by paleocentromere descent from the three tPCK subgenomes during the rediploidization process produced stable diploid *** rearrangement of the diploid species and their hybridization then contributed to Brassica *** subgenome dominance effect and biased gene retention,such as the over-retention of auxin-related genes after WGT,promoted functional gene evolution and thus propelled the expansion of rich morphotypes in the Brassica *** conclusion,the WGT event initiated subsequent genomic and gene-level evolution,which further drove Brassica speciation and created rich morphotypes in each species.

关键词： subsequent retention initiated

Growth Ring-dependent Fracture Toughness of Sea Urch.n Spines Estimated by Boundary Effect Model

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Journal of Bionic Engineering 2022年第5期19卷 1472-1480页

作者： Xiaona Liu Simin Liang Yingying Li Hongmei Ji xiaowu Li Department of Materials Physics and chemistry School of Material Science and EngineeringNortheastern UniversityShenyang 110819China Key Laboratory for Anistropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China State key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Although the fracture behavior of sea urch.n spines has been extensively investigated,there is as yet a lack of quantitative estimation on the effect of growth rings on the fracture properties of sea urch.n *** sea urch.n spines,much denser pores present in growth rings rather than porous *** tensile strength and fracture toughness of sea urch.n spine samples with different numbers of growth rings are measured by the Boundary Effect Model(BEM).The experimental results of single-edge notched three-point bending tests indicate that the BEM is an appropriate method to estimate the fracture toughness of the present porous sea urch.n spines,and the number of growth rings plays an important role in the fracture properties of ***,the tensile strength and fracture toughness of sea urch.n spines can be significantly improved with the increase in the number of growth rings,and their fracture toughness can even reach a relatively high value compared with some other porous materials with an identical *** present research findings are expected to provide a fundamental insight into the design of high-performance bionic materials with a highly porous structure.

关键词： Sea urch.n spine Growth ring Boundary Effect Model Porous structure Tensile strength Fracture toughness

Optimization of Grain Boundary character Distribution in Fe-18Cr-18Mn-0.63n High-nitrogen Austenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 497-502页

作者： Feng SHI xiaowu LI Yutong HU chuan SU ch.nming LIU Institute of Materials Physics and chemistry College of Sciences Northeastern University School of Materials and Metallurgy Northeastern University

Grain boundary engineering（GBE） is a practice of improving resistance to grain boundary failure of the material through increasing the proportion of low Σ coincidence site lattice（CSL） grain boundaries（special grain boundaries） in the grain boundary character distribution（GBCD）. The GBCD in a cold rolled and annealed Fe-18Cr-18Mn-0.63n high-nitrogen austenitic stainless steel was analyzed by electron back scatter difraction（EBSD）. The results show that the optimization process of GBE in the conventional austenitic stainless steel cannot be well applied to this high-nitrogen austenitic stainless steel. The percentage of low ΣCSL grain boundaries could increase from 47.3% for the solid solution treated high-nitrogen austenitic stainless steel specimen to 82.0% for the specimen after 5% cold rolling reduction and then annealing at 1423 K for 10 *** special boundaries of high proportion efectively interrupt the connectivity of conventional high angle grain boundary network and thus achieve the GBCD optimization for the high-nitrogen austenitic stainless steel.

关键词： High nitrogen austenitic stainless steel Grain boundary character distri-bution CSL grain boundary EBSD

Selective recovery of lithium from simulated brine using different organic synergist

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ch.nese Journal of chemical Engineering 2019年第2期27卷 335-340页

作者： Huifang Li Lijuan Li xiaowu Peng Lianmin Ji Wu Li Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences Key Laboratory of Salt Lake Resources chemistry of Qinghai Province University of ch.nese Academy of Sciences Qinghai University

The organic synergists, including Octanol, ethyl acetate(EA), butyl acetate(BA), methyl isobutyl ketone(MIBK),diisobutyl ketone(DIBK), n,n-bis(2-ethylhexyl) acetamide(n523) and 8-hydroxylquiolate, were added to the TBP–FeCl_3 extraction system to extract lithium from brine. The effects of concentration of organic synergist and total organic extractant, molar ratio of Fe/Li, phase ratio, counter-current extraction and the acidity of stripping agent on lithium extraction were investigated to optimize the extraction conditions. Under the optimize conditions, the results of counter-current extraction showed the mixed extraction system was the preponderance on the lithium extraction. Especially the separation of lithium in organic phase and aqueous phase and the separation mass ratio of Mg/Li increased greatly. An extraction mech.nism was proposed based on the analysis of FT-IR spectra and Raman spectra.

关键词： Organic synergist Lithium extraction Mixed extraction system Mech.nism