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中性和碱性盐复合胁迫对2个小麦品种种子萌发和幼苗生长的影响

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干旱地区农业研究 2024年第4期42卷 29-41页

作者：李刚付凯勇王焱栋李超魏加练李春艳李诚石河子大学农学院新疆生产建设兵团绿洲生态农业兵团重点实验室新疆石河子832003

为了解不同浓度的中性盐及碱性盐复合胁迫对2个小麦品种‘新冬26号’和‘金石农1号’种子萌发及幼苗生长的影响,分别设置0、50、100、200、300 mmol·L^(-1)的中性盐(NaCl)及碱性盐复合(Na 2 CO 3+NaHCO 3,摩尔比1∶1)胁迫浓度,测定小... 详细信息

为了解不同浓度的中性盐及碱性盐复合胁迫对2个小麦品种‘新冬26号’和‘金石农1号’种子萌发及幼苗生长的影响,分别设置0、50、100、200、300 mmol·L^(-1)的中性盐(NaCl)及碱性盐复合(Na 2 CO 3+NaHCO 3,摩尔比1∶1)胁迫浓度,测定小麦种子萌发过程中淀粉粒形态变化、α-淀粉酶活性、可溶性糖含量、质膜相对透性、发芽及生长相关指标的变化。结果表明:(1)中性盐胁迫下,‘新冬26号’萌发3 d后淀粉粒降解程度高于‘金石农1号’,而碱性盐复合胁迫下则相反。(2)随盐胁迫浓度的增加,与对照相比,‘新冬26号’小麦在中性盐胁迫下发芽势、发芽率下降幅度分别为3.37%~78.65%、2.25%~42.70%,在碱性盐复合胁迫下相应下降幅度分别为19.10%~100.00%、17.98%~100.00%;‘金石农1号’在中性盐胁迫下发芽势、发芽率下降幅度分别为4.50%~96.63%、3.37%~95.51%,在碱性盐复合胁迫下两指标下降幅度均为2.62%~100.00%。(3)中性盐胁迫下,与‘新冬26号’相比,‘金石农1号’籽粒的α-淀粉酶活性和可溶性糖含量变化范围分别为-25.59%~3.69%和-69.00%~184.01%;在碱性盐复合胁迫下,与‘新冬26号’相比,‘金石农1号’籽粒的α-淀粉酶活性和可溶性糖含量变化范围分别为-21.54%~40.48%和-15.51%~134.67%。(4)‘新冬26号’耐盐等级在中性盐胁迫200 mmol·L^(-1)和300 mmol·L^(-1)时均高于‘金石农1号’,‘金石农1号’耐碱等级在碱性盐复合胁迫200 mmol·L^(-1)时高于‘新冬26号’。(5)盐敏感指标的回归方程表明中性盐胁迫下小麦种子的平均耐盐临界值和平均致死极限浓度分别为258.24 mmol·L^(-1)和514.62 mmol·L^(-1),碱性盐复合胁迫下分别为109.47 mmol·L^(-1)和280.05 mmol·L^(-1)。

关键词：小麦中性盐胁迫碱性盐复合胁迫种子萌发幼苗生长

TmNAS1,a nicotianamine synthase gene from Triticum monococcum improve Fe accumulation of transgenic tobacco under Fe stress

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TmNAS1,a nicotianamine synthase gene from Triticum monococcu...

不同浓度MeJA对头花蓼光合和荧光特性的影响

第十届全国小麦基因组学及分子育种大会

作者： Xuye Du jialian wei Bin Zhu Feng Yu Hongcheng Wang Tuo Zeng Qingbei Weng Jiefang He School of Life Sciences Guizhou Normal University

Nicotianamine synthase(NAS) plays a key role in maintaining homeostasis of heavy metals in *** this study,the TmNAS1 gene from Triticum monococcum has been transformed into tobacco and the tolerance of Fe stress of transgenic and wild type(WT) tobacco was *** of TmNAS1 in tobacco led to enhance Fe stress tolerance,which was demonstrated by the growth and higher Fe content of transgenic tobacco plants compared with WT when exposed to 500 mM *** investigation showed that transgenic tobacco plants displayed lower malondialdehyde(MDA) level,higher contents of chlorophyll,Fe and proline accompanied by increased peroxidase(POD),superoxide dismutase(SOD),and catalase(CAT) *** results indicate that TmNAS1 plays a positive role in Fe tolerance by improving the antioxidant defense system.

关键词： TmNAS1 Fe tolerance transgenic tobacco molecular mechanism

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东北农业科学 2019年第4期44卷 37-42,109页

作者：赵许朋刘燕魏加练陈学梅姜婷施豪贵阳学院

以苗药头花蓼为研究对象,对其在不同浓度茉莉酸甲酯处理下叶片的光合和荧光特性进行了研究,以期能够为外源物质在头花蓼栽培过程中的应用提供理论依据。结果表明:当茉莉酸甲酯(MeJA)在0~7.5 mmol/L范围内变化时,头花蓼的净光合速率(Pn)... 详细信息

以苗药头花蓼为研究对象,对其在不同浓度茉莉酸甲酯处理下叶片的光合和荧光特性进行了研究,以期能够为外源物质在头花蓼栽培过程中的应用提供理论依据。结果表明:当茉莉酸甲酯(MeJA)在0~7.5 mmol/L范围内变化时,头花蓼的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、胞间二氧化碳浓度(Ci)、实际量子产量(Y(Ⅱ))、最大光量子产量(Fv/Fm)、最大荧光(Fm)、光化学猝灭系数(qP)均呈现先上升后下降趋势,初始荧光(F0)呈现上升趋势,非光化学猝灭系数(NPQ)呈现下降趋势,Ci极值出现在0.1 mmol/L,而Pn、Gs、Tr、Ci、Y(Ⅱ)、Fv/Fm、Fm、qP出现在0.5 mmol/L处,当MeJA浓度低于0.5 mmol/L,F0与NPQ变化不明显,当MeJA浓度超过0.5 mmol/L时,F0与NPQ变化明显。综上分析,0.5 mmol/L茉莉酸甲酯明显提高头花蓼的光合效率,超过0.5 mmol/L后,茉莉酸甲酯不会对头花蓼光合系统有显著的伤害,Pn虽然呈下降趋势但是与气孔因素有关。

关键词：头花蓼茉莉酸甲酯光合荧光

Numerical Experiment of the Solid Particle Erosion of Bionic Configuration Blade of Centrifugal Fan

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Acta Metallurgica Sinica(English Letters) 2013年第1期26卷 16-24页

作者： Junqiu ZHANG Zhiwu HAN wei YIN Huiyuan WANG Chao GE jialian JIANG Key Laboratory of Bionics Engineering of Ministry of Education Jilin University College of Materials Science and Engineering Jilin University

In this paper, a bionic method was presented to improve the erosion resistance of blade of the centrifugal fan. A numerical investigation of the solid particle erosion on the standard and bionic configuration blade of 4-72N_o10C centrifugal fan was presented. The numerical study employs computational fluid dynamics （CFD） software, based on a finite volume method, in which the discrete phase model was used to modele the solid particles flow, and the Eulerian conservation equation was adopt to simulate the continuous phase. Moreover, user-defined function was used to define wear equation. The various diameters of the particles were taken into account. The positions of collision of standard and bionic fan blades were discussed, and two kinds of centrifugal fan blade wear were compared. The results show that the particles from the incident source with different positions have different processes of turning and movement when enter into the impeller. The trajectories of flow in the fan channel are significantly different for the particles with different diameters. Bionic fan blade have lower erosion rate than the standard fan blade when the particle size is 20 μm. The anti-erosion mechanism of the bionic fan blade was discussed.

关键词： Bionic Numerical simulation Centrifugal fan blade Erosion resistance

Erosion-Resistant Surfaces Inspired by Tamarisk

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Journal of Bionic Engineering 2013年第4期10卷 479-487页

作者： Zhiwu Han wei Yin Junqiu Zhang jialian Jiang Shichao Niu Luquan Ren Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changchun 130022 P. R. China

Tamarisk, a plant that thrives in arid and semi-arid regions, has adapted to blustery conditions by evolving extremely ef- fective and robust anti-erosion surface patterns. However, the details of these unique properties and their structural basis are still unexplored. In this paper, we demonstrate that the tamarisk surface only suffers minor scratches under wind-sand mixture erosion. The results show that the anti-erosion property of bionic sample, inspired by tamarisk surface with different surface morphologies, can be attributed to the flow rotating in the grooves that reduces the particle impact speed. Furthermore, the simulation and experiment on the erosion wear behavior of the bionic samples and bionic centrifugal fan blades show that the bionic surface with V-type groove exhibits the best erosion resistance. The bionic surface on centrifugal fan blades with opti- mum parameters can effectively improve anti-erosion property by 28.97%. This paper show more opportunities for bionic application in improving the anti-erosion performance of moving parts that work under dirt and sand particle environment, such as helicopter rotor blades, airplane propellers, rocket motor nozzles, and pipes that regularly wear out from erosion.

关键词： tamarisk anti-erosion numerical simulation bionic centrifugal fan blades

Application Study of Climatic Feasibility Demonstration of Airport Project Site Selection

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Meteorological and Environmental Research 2020年第4期11卷 34-35,42页

作者： Zhiyu LONG Dingman SONG jialian WEN wei FU Yongzhou Meteorological Bureau of Hunan Province Yongzhou 425100China

According to the Technical Guide for Climatic Feasibility Demonstration of Airport Project Site Selection,via statistical analysis on historical climate data of reference weather station,climatic background characteristics and meteorological disaster situation of preselected site,and characteristics of seasonal distribution,interannual variation and long-term trend of main meteorological elements and disasters were *** difference of meteorological elements between preselected site and reference weather station and its cause were analyzed,and fine analysis of fog,low visibility event,wind,cloud and other meteorological elements or weather with high influence in preselected site was *** feasibility,advantages and disadvantages of meteorological conditions and possible meteorological risks in preselected site were *** research could provide decision-making basis for site selection of Lingling Airport and airport engineering ***,key technology route and research results were extracted,and technical analysis process of demonstration report was integrated,which could provide reference for climate feasibility demonstration on site selection of similar airports in China.

关键词： Airport project site selection Climatic feasibility demonstration Reference weather station Preselected site

Observation of magnetic droplets in magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2022年第2期65卷 99-105页

作者： Kewen Shi Wenlong Cai Sheng Jiang Daoqian Zhu Kaihua Cao Zongxia Guo Jiaqi wei Ao Du Zhi Li Yan Huang jialiang Yin Johan Akerman weisheng Zhao Fert Beijing Institute M1IT Key Laboratory of SpintronicsSchool of Integrated Circuit Science and EngineeringBeihang UniversityBeijing 100191China Beihang-Goertek Joint Microelectronics Institute Qingdao Research InstituteBeihang UniversityQingdao 266000China Department of Physics University of GothenburgGothenburg 41296Sweden Department of Applied Physics School of Engineering Sciences.KTH Royal Institute of TechnologyKista 16440Sweden School of Microelectronics Northwestern Poly technical UniversityXi'an 710072China

Magnetic droplets,a class of highly nonlinear magnetodynamic solitons,can be nucleated and stabilized in nanocontact spintorque *** we experimentally demonstrate magnetic droplets in magnetic tunnel junctions(MTJs).The droplet nucleation is accompanied by power enhancement compared with its ferromagnetic resonance *** nucleation and stabilization of droplets are ascribed to the double-Co Fe B free-layer structure in the all-perpendicular MTJ,which provides a low Zhang-Li torque and a high pinning *** results enable better electrical sensitivity in fundamental studies of droplets and show that the droplets can be utilized in MTJ-based applications and materials science.

关键词： spin-torque nano-oscillators magnetic droplets spin dynamics magnetic tunnel junctions

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曲线交叠外推的微动多目标宽带分辨算法

电子与信息学报 2019年第12期41卷 2889-2895页

作者：魏嘉琪张磊刘宏伟盛佳恋西安电子科技大学雷达信号处理国家重点实验室西安710071 西安电子科技大学信息感知技术协同创新中心西安710071 上海无线电设备研究所上海201109

针对传统的微多普勒特征提取技术难以解决多目标分辨和微动参数估计这一问题,该文针对进动多目标,提出一种曲线交叠外推的微动多目标宽带分辨算法。该算法以各个滤波数据点间的相对距离为准则,结合各曲线的历史斜率信息,对交叠点后的点... 详细信息

针对传统的微多普勒特征提取技术难以解决多目标分辨和微动参数估计这一问题,该文针对进动多目标,提出一种曲线交叠外推的微动多目标宽带分辨算法。该算法以各个滤波数据点间的相对距离为准则,结合各曲线的历史斜率信息,对交叠点后的点迹进行外推估计,实现各个分量信号微动曲线的区分关联。在此基础上,通过分析各曲线的微动特性差异实现多目标分辨。仿真实验验证了所提算法的有效性和稳定性。

关键词：多目标分辨微动特征提取数据关联参数估计

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胰腺囊腺肿瘤的影像诊断

西安交通大学学报（医学版） 2005年第5期26卷 511-512页

作者：马家莲张华魏炜西安交通大学第一医院超声波室陕西西安710061

目的进一步探讨胰腺囊腺肿瘤的影像学特征及临床应用价值。方法分析经手术和病理证实的17例胰腺囊腺肿瘤的临床表现及影像学特征。结果超声检查17例,可以显示肿瘤大小、位置轮廓,可了解肿瘤囊壁厚度、回声及有无分隔情况;CT检查15例,增... 详细信息

目的进一步探讨胰腺囊腺肿瘤的影像学特征及临床应用价值。方法分析经手术和病理证实的17例胰腺囊腺肿瘤的临床表现及影像学特征。结果超声检查17例,可以显示肿瘤大小、位置轮廓,可了解肿瘤囊壁厚度、回声及有无分隔情况;CT检查15例,增强后囊肿不强化,囊壁实性结节明显强化。上消化道钡餐造影(GI)13例,可见胃肠道受压移位;逆行胰胆管造影(ERCP)3例,见胰管受压移位。结论超声和CT是诊断胰腺囊腺肿瘤的有效方法,二者结合可提高诊断率,GI和ERCP在鉴别诊断上有一定价值。

关键词：胰腺囊腺肿瘤影像诊断