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The effect of hydrogen on the electronic structure of kink in bcc iron

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science china(Technological sciences) 2009年第5期52卷 1212-1218页

作者： chen liqun1,QIU Zhengchen1,yu tao2 & wang chongyu2.3.4 1 college of sciences,central south university of forestry and technology,changsha 410004,china 2 central Iron and steel Research Institute,Beijing 100081,china 3 Department of Physics,Tsinghua university,Beijing 100084,china 4 International Center for Materials Physics,Chinese Academy of sciences,shenyang 110016,china 1. college of sciences Central South University of Forestry and Technology Changsha 410004 China 2. central Iron and steel Research Institute Beijing 100081 China 3. Department of Physics Tsinghua University Beijing 100084 China 4. International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

The electronic structures of kinks in the [100](010) and 1/2.111](-110) edge dislocations in bcc iron containing hydrogen are investigated by means of the first-principles DMol method and the discrete variational *** effects of hydrogen on the kinks are *** results show that hydro-gen forms weak bonding states with its neighboring host atoms,and since hydrogen draws charge from its neighboring host atoms,the interactions between most of the host atoms are weakened com-pared with those of the corresponding atomic pairs in the clean *** indicates that the migration of kink,*** motion of dislocation,is easier in the doping hydrogen kink than in the clean kink,which may be the solid solution softening effect resulting from the impurity hydrogen.

关键词： electronic structure dislocation kink impurity

First-principles investigation of the impurity-kink interaction in bcc iron

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Chinese science Bulletin 2008年第12期53卷 1796-1803页

作者： yu tao chen liqun wang chongyu QIU Zhengchen DU JunPing central Iron and steel Research Institute Beijing 100081 China college of sciences Central South University of Forestry and Technology Changsha 410004 China Department of Physics Tsinghua University Beijing 10084 China

Using the first-principles self-consistent discrete variational method based on density functional theory, we investigated the effect of light impurities C and N on the electronic structure of kink on the [100](010) edge dislocation (ED) in bcc iron. Our energetic calculations show that the light impurities have a strong segregation tendency to enter the kink. The results of the charge distribution and the local den-sity of states indicate that the strong bonds between the impurity atoms and the neighboring Fe atoms are formed due to the hybridizations of impurity atoms 2p states and Fe 3d4s4p states. The introduction of light impurities can stabilize the kink system, and impedes the sideward motion of the kink in the [100](010) ED. This is, the light impurities induce a strong pinning effect on the [100](010) ED and may result in the solid solute hardening.

关键词：电子结构交互作用杂质密度泛函理论铁

The effect of boron on the electronic structure of dislocation in NiAl

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science china(Physics,Mechanics & Astronomy) 2011年第5期54卷 815-820页

作者： chen liqun yu tao college of sciences Central South University of Forestry & Technology Changsha 410004 China central Iron and steel Research Institute Beijing 100081 China

The segregation effect of B on the [100]（010） edge dislocation core in NiA1 single crystals is investigated using the DMol method and the discrete variational method within the framework of density functional theory. The impurity segregation en- ergy and the charge distribution are calculated. The effects of B on the dislocation motion are discussed. The results show that B prefers to segregate at the Center-Al dislocation core. Moreover, B forms strong bonding states with its neighboring host atoms, which may not be beneficial to the motion of the dislocation. Therefore, it can be expected that the strength of NiAl single crystals may be increased.

关键词： electronic structure dislocation impurity

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贵州枇杷种质资源分布及其产业发展概述

果树学报 2024年第2期41卷 338-352页

作者：杨勇胜王道静陈阳松范付华魏椿余桃江旭升李庆宏李斌陈树红贵阳市农业试验中心贵阳550018 贵州大学林学院贵阳550025

贵州立体气候突出,野生枇杷种质资源丰富,性状差异性明显。目前已找到普通枇杷、大花枇杷、小叶枇杷3个种类,普通枇杷在全省广泛分布,大花枇杷主要分布在黔东南州雷公山一带,小叶枇杷主要分布在黔西南州兴义市一带。贵州省枇杷商品化栽... 详细信息

贵州立体气候突出,野生枇杷种质资源丰富,性状差异性明显。目前已找到普通枇杷、大花枇杷、小叶枇杷3个种类,普通枇杷在全省广泛分布,大花枇杷主要分布在黔东南州雷公山一带,小叶枇杷主要分布在黔西南州兴义市一带。贵州省枇杷商品化栽培始于1958年,由黔东南州率先从江苏、浙江、福建等省引进优良品种进行试验示范。进入20世纪80年代中后期,贵阳市、黔南州、黔西南州等各地州(市)相继开展引种试验及小规模推广应用。截至2.10年,在贵阳市、黔东南州、毕节市等地区拥有了万亩以上的规模化种植。特别是2.15年以来,贵州各地枇杷种植生产发展速度迅猛,据2022年贵州省农业农村厅统计数据,全省枇杷种植面积已达2.3万hm^(2),年产量16.3万t,产值达17.1亿元,鲜果采摘期超过2个月。但栽培技术与管理水平仍较低,面积上升与产量增长不成正比,全省平均每666.7 m^(2)商品果产量不足500 kg,提升空间很大。存在问题主要为,一是缺乏地方规范的引、试、推制度体系,盲目性引种,造成品种混杂,良莠不齐,商品性低;二是对遗传优良性状的种质资源挖掘不足,缺乏地方特色的主导品种,市场竞争力不强;三是枇杷品牌创建与营销策略意识不强,形成行业内竞争压价销售,影响效益;四是鲜果产后冷链及深加工产品技术研发滞后,产业附加值增长有限;五是旱涝寒暑等极端天气频繁出现,山地果园设施栽培配套条件滞后,抗风险能力不强等。主要围绕贵州枇杷种质资源分布特征、引种与育种、栽培技术演变、产业发展及其制约因子等方面进行了分析,尝试提出贵州枇杷产业当前与未来的主要任务,以推动枇杷产业高质量发展。

关键词：枇杷贵州种质资源分布产业

Ru对NiAl[100](010)刃型位错电子结构的影响

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金属学报 2019年第2期55卷 223-228页

作者：陈丽群邱正琛于涛中南林业科技大学理学院长沙410004 钢铁研究总院功能材料研究所北京100081

利用DMol和离散变分法,研究了Ru在NiAl [100](010)刃型位错中择优占位和合金化效应。杂质偏聚能的计算结果表明,Ru会优先占据Al心位错芯中的Al格位。原子间相互作用能、电荷密度和态密度的分析表明,杂质原子和相邻基体原子之间形成了较... 详细信息

利用DMol和离散变分法,研究了Ru在NiAl [100](010)刃型位错中择优占位和合金化效应。杂质偏聚能的计算结果表明,Ru会优先占据Al心位错芯中的Al格位。原子间相互作用能、电荷密度和态密度的分析表明,杂质原子和相邻基体原子之间形成了较强的化学键,使Ru原子与位错芯区近邻基体原子间因强相互作用形成一个整体。此外,在掺杂体系中,穿过滑移面的基体原子间相互作用减弱,而沿滑移方向基体原子间的相互作用加强。这样的成键特性有利于位错线沿滑移面的移动形成扭折,扭折的成核及迁移促使位错运动,从而改善NiAl合金的韧性。

关键词：电子结构位错金属间化合物 Ru

How do groups of red imported fire ants （Hymenoptera： Formicidae） feed on a droplet of sugar water？

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Insect science 2018年第3期25卷 499-507页

作者： Cai wang Xuan chen Linda M. Hooper-Bùi Rachel strecker yu-Zhen Wen Wen-Quan Qin tao Ma Zhao-Hui sun Xiao-Yang chen Xiu-Jun Wen Guangdong Key Laboratory for Innovation Development and Utilization of Forest Plant Germplasm College of Forestry and Landscape Architecture South China Agricultural University Guangzhou China Department of Entomology Louisiana State University Agricultural Center Baton Rouge LA USA Department of Environmental sciences Louisiana State University Baton Rouge LA USA

Many previous studies have focused on the foraging behaviors and strategies of the red imported fire ants, solenopsis invicta Buren on solid food or granular bait; little attention has been paid to how liquid sugar is fed upon. In the present study, behavioral responses ofs. invicta to 25% sucrose water droplets were observed. Five foraging patterns were identified in s. invicta colonies under laboratory conditions：（i） no feeding, no sucrose water feeding was observed; （ii） surround feeding, ants surrounded and fed along the edge of the sucrose droplet; （iii） stacked feeding, ants stacked and fed along the edge of the sucrose droplet; （iv） droplet-break feeding, ants broke the liquid droplet and sucked sucrose water that spread on surface of the substance or soil particles previously transported by ants; and （v） cover feeding, whole surface of the sucrose droplet was covered by layers of feeding ants. This is the first time cover feeding in s. invicta has been reported, which obviously requires more ants compared to the other patterns. In addition, individual ants were tracked in videos under laboratory conditions, and behavioral repertoires that led to stacking, covering and droplet-breaking were identified and described. The field investigation showed that surround feeding was most frequently performed by s. invicta foragers; however, cover feeding was not observed under field conditions during this study. Both laboratory and field studies showed colony-level variations in sugar-water feeding.

关键词： colony variation foraging liquid food solenopsis invicta sugar water

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柚木野螟成虫复眼外部形态和超微结构观察

昆虫学报 2022年第8期65卷 1056-1067页

作者：苑鹏宇胡可炎钱沉鱼王胜坤温秀军王偲马涛华南农业大学林学与风景园林学院广州510642 中国林业科学研究院热带林业研究所广州510520

【目的】柚木野螟Eutectona machaeralis主要取食危害珍贵树种柚木。本研究旨在观察研究柚木野螟成虫复眼的形态、组织结构和超微结构,分析其复眼结构特征,为更好了解该物种复杂的视觉行为与感光、趋光机制的关系奠定基础。【方法】运... 详细信息

【目的】柚木野螟Eutectona machaeralis主要取食危害珍贵树种柚木。本研究旨在观察研究柚木野螟成虫复眼的形态、组织结构和超微结构,分析其复眼结构特征,为更好了解该物种复杂的视觉行为与感光、趋光机制的关系奠定基础。【方法】运用光学显微镜以及扫描和透射电子显微镜技术观察了柚木野螟成虫复眼的形态、组织结构和超微结构。【结果】柚木野螟成虫复眼着生于头部触角基部,呈椭球形,属对称性复眼。雌、雄成虫复眼分别有2300~2755和1950~2.16个小眼。小眼呈正六边形,表面密被角膜乳突,间隙偶有感觉毛。每个小眼由1个角膜、4个晶锥细胞、1对初级色素细胞,6个次级色素细胞、不同水平面分布的12个视网膜细胞和基膜等组成。沿小眼纵轴11个视网膜细胞的向心侧细胞膜特化成细丝状微绒毛,形成放射状排列的视小杆,组合呈融合型视杆;第12个视网膜细胞位于小眼基部。基膜上方,视网膜细胞和次级色素细胞末端膨大,以轴突形式穿过基底膜。【结论】柚木野螟复眼为典型的重叠像眼,雌、雄成虫小眼排列方式及内部结构无明显差异,但雌、雄虫小眼数量和大小具有明显的性二型现象。

关键词：柚木野螟超微结构复眼小眼重叠像眼

Chromosome-scale assembly and evolution of the tetraploid salvia splendens (Lamiaceae) genome

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Horticulture Research 2021年第1期8卷 2721-2735页

作者： Kai-Hua Jia Hui Liu Ren-Gang Zhang Jie Xu shan-shan Zhou si-Qian Jiao Xue-Mei Yan Xue-Chan Tian Tian-Le shi Hang Luo Zhi-Chao Li yu-tao Bao shuai Nie Jing-Fang Guo Ilga Porth Yousry AEl-Kassaby Xiao-Ru wang Charles chen Yves Van de Peer Wei Zhao Jian-Feng Mao Beijing Advanced Innovation Center for Tree Breeding by Molecular Design National Engineering Laboratory for Tree BreedingKey Laboratory of Genetics and Breeding in Forest Trees and Ornamental PlantsMinistry of EducationCollege of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China Ori(shandong)Gene science and technology Co. LtdWeifang 261000 ShandongChina Department des sciences du Bois et de la Foret Facultede Foresteriede Geographie et GeomatiqueUniversite LavalQuebec CityQC G1V 0A6Canada Department of Forest and Conservation sciences Faculty of ForestryUniversity of British ColumbiaVancouverBC V6T 1Z4Canada Department of Ecology and Environmental science UmeåPlant Science CentreUmeåUniversitySE-90187 UmeåSweden Department of Biochemistry and Molecular Biology 246 Noble Research CenterOklahoma State UniversityStillwaterOKUSA Department of Plant Biotechnology and Bioinformatics Ghent UniversityGhentBelgium VIB Center for Plant systems Biology 9052 GhentBelgium Centre for Microbial Ecology and Genomics Department of BiochemistryGenetics and Microbiology GeneticsUniversity of PretoriaPrivate Bag X20Pretoria 0028South Africa college of Horticulture Academy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjing 210095China

Polyploidization plays a key role in plant evolution,but the forces driving the fate of homoeologs in polyploid genomes,i.e.,paralogs resulting from a whole-genome duplication(WGD)event,remain to be ***,we present a chromosome-scale genome assembly of tetraploid scarlet sage(salvia splendens),one of the most diverse ornamental *** found evidence for three WGD events following an older WGD event shared by most eudicots(theγevent).A comprehensive,spatiotemporal,genome-wide analysis of homoeologs from the most recent WGD unveiled expression asymmetries,which could be associated with genomic rearrangements,transposable element proximity discrepancies,coding sequence variation,selection pressure,and transcription factor binding site *** observed differences between homoeologs may reflect the first step toward sub-and/or *** assembly provides a powerful tool for understanding WGD and gene and genome evolution and is useful in developing functional genomics and genetic engineering strategies for scarlet sage and other Lamiaceae species.

关键词： species evolution assembly

基于高通量测序的鹿角杯形珊瑚微卫星标记的开发

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广西大学学报（自然科学版） 2020年第4期45卷 958-965页

作者：罗燕秋黄雯余克服李明武茜王英辉李扬陶永健陈胤民广西大学珊瑚礁研究中心广西南宁530004 广西南海珊瑚礁研究重点实验室广西南宁530004 广西大学海洋学院广西南宁530004 广西大学林学院广西南宁530004

为了更深入开展珊瑚遗传结构及其多样性研究,本研究采用高通量测序对鹿角杯形珊瑚进行微卫星标记的开发。首先用人工白化的方法获得污染较低的鹿角杯形珊瑚,然后使用该样品DNA,基于高通量测序平台对鹿角杯形珊瑚简化基因组进行了测序,... 详细信息

为了更深入开展珊瑚遗传结构及其多样性研究,本研究采用高通量测序对鹿角杯形珊瑚进行微卫星标记的开发。首先用人工白化的方法获得污染较低的鹿角杯形珊瑚,然后使用该样品DNA,基于高通量测序平台对鹿角杯形珊瑚简化基因组进行了测序,最终设计得到鹿角杯形珊瑚微卫星引物2786对。利用海南三亚鹿角杯形珊瑚对其中6对多态性较高的微卫星标记进行了评价。每个微卫星位点的有效等位基因数(Ne)为2.198~5.000;观测杂合度(Ho)为0.531~0.875;期望杂合度(He)为0.512~0.816;shannon多样性指数为0.856~1.829;多态信息含量(PIC)为0.441~0.777,其中有4对微卫星标记呈现为高度多态性(PIC>0.5),2对微卫星标记为中度多态性。经过Bonferroni校正后,只有微卫星标记LB11偏离哈迪—温伯格平衡;连锁不平衡检验结果表明,位点之间不存在连锁不平衡现象。

关键词：鹿角杯形珊瑚人工白化高通量测序微卫星标记多态性