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Effects of Acetylcholine, Cytochalasin B and Amiprophosmethyl on Phloem Transport in Radish （Raphanus sativas）

Journal of Integrative Plant Biology 2007年第4期49卷 550-555页

作者： chong-jun yang Zhi-Xi Zhai Yu-Hai Guo Peng Gao Laboratory of Crop Physiology China Agricultural University Beijing 100094 China College of Agronomy Liaocheng University Liaocheng 252000 China State Key Laboratory of Plant Physiology and Biochemistry China Agricultural University Beijing 100094 China

We investigated the role of the ＂sieve tube-companion cell complex＂ lining the tube periphery, particularly the microfilament and microtubule, in assisting the pushing of phloem sap flow. We made a simple phloem transport system with a living radish plant, in which the conducting channel was exposed for local treatment with chemicals that are effective in modulating protoplasmic movement （acetylcholine, （ACh） a neurotransmitter in animals and insects; cytochalasin B, （CB） a specific inhibitor of many cellular responses that are mediated by microfilament systems and amiprophos-methyl, （APM） a specific inhibitor of many cellular responses that are mediated by microtubule systems）. Their effects on phloem transport were estimated by two experimental devices：（i） a comparison of changes in the amount of assimilates in terms of carbohydrates and ^14C-labeled photosynthetic production that is left in the leaf blade of treated plants; and （ii） distribution patterns of ^14C-labeled leaf assimilates in the phloem transport system. The results indicate that CB and APM markedly inhibited the transfer of photosynthetic product from leaf to root via the leaf vein, while ACh enhanced the transfer of photosynthetic product in low concentrations （5.0×10^-4 mol/L） but inhibited it in higher concentrations （2.0×10^-3 mol/L） from leaf to root via the leaf vein. Autoradiograph imaging clearly reveals that ACh treatment is more effective than the control, and both CB and APM treatments effectively inhibit the passage of radioactive assimilates. All of the results support the postulation that the peripheral protoplasm in the sieve tube serves not only as a passive semi-permeable membrane, but is also directly involved in phloem transport.

关键词： assimilate phloem protoplasm translocation vascular bundle.

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基于内容的图像检索系统的设计与实现

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计算机科学 2004年第2期31卷 139-141页

作者：许营坤王崇骏杨育彬陈世福南京大学计算机软件新技术国家重点实验室南京210093

本文描述了基于内容的图像检索系统@IMAGE的设计和实现。该系统综合运用了多媒体、媒体存储、数据组织和表示方法、图像检索技术等。也介绍了基于图像颜色、形状和纹理的检索算法。给出了@IMAGER系统结构、实现技术和功能。

关键词：图像检索系统图像标识图像匹配算法图像处理图像识别多媒体

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Spatial distribution of shallow landslides caused by Typhoon Lekima in 2019 in Zhejiang Province, China

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Journal of Mountain Science 2024年第5期21卷 1564-1580页

作者： CUI Yulong yang Liu XU chong ZHENG jun School of Civil Engineering and Architecture Anhui University of Science and TechnologyHuainan 232001China National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Department of Civil Engineering Zhejiang UniversityHangzhou 310058China

In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous terrain of this area, combined with rapid rainfall accumulation, has led to a surge in flash floods and severe geological hazards. On August 10, 2019, Typhoon Lekima made landfall in Zhejiang Province, China, and its torrential rainfall triggered extensive landslides, resulting in substantial damage and economic losses. Utilizing high-resolution satellite images, we compiled a landslide inventory of the affected area, which comprises a total of 2,774 rainfallinduced landslides over an area of 2965 km2. The majority of these landslides were small to mediumsized and exhibited elongated, clustered patterns. Some landslides displayed characteristics of high-level initiation, obstructing or partially blocking rivers, leading to the formation of debris dams. We used the inventory to analyze the distribution pattern of the landslides and their relationship with topographical, geological, and hydrological factors. The results showed that landslide abundance was closely related to elevation, slope angle, faults, and road density. The landslides were predominantly located in hilly and low mountainous areas, with elevations ranging from 150 to 300 m, slopes of 20 to 30 degrees, and a NE-SE aspect. Notably, we observed the highest Landslide Number Density(LND) and Landslide Area Percentage(LAP) in the rhyolite region. Landslides were concentrated within approximately 4 km on either side of fault zones, with their size and frequency negatively correlated with distances to faults, roads, and river systems. Furthermore, under the influence of typhoons, regions with denser vegetation cover exhibited higher landslide density, reaching maximum values in shrubland areas. In areas experiencing significantly increased concentrated rainfall, landslide density also showed a corr

关键词： Typhoon rainfall Landslide characteristics Spatial distribution Southeast coastal region

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顶空气相色谱法测定胡芦巴总皂苷中树脂残留物的研究

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天然产物研究与开发 2004年第5期16卷 439-441页

作者：黄卫平袁崇均杨红王笳陈帅徐学民四川省中药研究所成都610041

采用顶空气相色谱法 ,对胡芦巴 (FLB)总皂苷中树脂残留物正庚烷、苯、正癸烷、甲苯、二甲苯、苯乙烯、二乙烯基苯与乙基苯乙烯进行检测 ,8种树脂残留物被完全分离 ,其峰面积与浓度在所考察浓度范围内具有良好的线形关系 ,R为 0 .99996～... 详细信息

采用顶空气相色谱法 ,对胡芦巴 (FLB)总皂苷中树脂残留物正庚烷、苯、正癸烷、甲苯、二甲苯、苯乙烯、二乙烯基苯与乙基苯乙烯进行检测 ,8种树脂残留物被完全分离 ,其峰面积与浓度在所考察浓度范围内具有良好的线形关系 ,R为 0 .99996～ 1.0 0 0 0 0 ,平均回收率 97.5 9%～ 10 3.5 8% ,精密度的RSD均小于 6 %。本实验建立的色谱方法灵敏、准确 ,适用于胡芦巴总皂苷中树脂残留物的检测。

关键词：总皂苷胡芦巴顶空气相色谱法残留物 RSD 灵敏实验树脂乙基苯苯乙烯

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Minor antifungal aromatic glycosides from the roots of Gentiana rigescens(Gentianaceae)

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Chinese Chemical Letters 2009年第10期20卷 1215-1217页

作者： Min Xu chong Ren yang Ying jun Zhang State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciences Kunming 650204 China

Two new phenolic glycosides, 2,3-dihydroxybenzoic acid methyl ester 3-O-β-o-glucopyranosyl-（1-6）-β-D-glucopyranoside （1） and 2,5-dihydroxylbenzofuran 5-O-β-D-xylopyranosyl-（1-6）-O-β-D-glucopyranoside （2）, were isolated as the minor chemical constituents from the roots of Gentiana rigescens, along with 15 known compounds. Their structures were elucidated by detailed spectroscopic analysis, including 1D, 2D NMR and chemical method. All of these compounds were isolated for the first time from the title plant. Moreover, compounds 1 and 2 were tested for the antifungal activities on three plant pathogens Peronophythora litchi, Glomerella cingulata, and Glorosprium musarum.

关键词： Gentiana rigescen Phenolic glycosides Anfifungal activity Plant pathogen

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Preliminary design of an SCO_(2) conversion system applied to the sodium cooled fast reactor

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Frontiers in Energy 2021年第4期15卷 832-841页

作者： Hongyi yang Xiaoyan yang jun yang Quanbin ZHAO Xiaokun WANG Daotong chong Chanjuan TANG Chengyuan JIANG China Institute of Atomic Energy Beijing 102413China

The supercritical carbon dioxide(SCO_(2))Brayton cycle has become an ideal power conversion system for sodium-cooled fast reactors(SFR)due to its high efficiency,compactness,and avoidance of sodiumwater *** this paper,the 1200 MWe large pool SFR(CFR1200)is used as the heat source of the system,and the sodium circuit temperature and the heat load are the operating boundaries of the cycle *** performance of different SCO_(2) Brayton cycle systems and changes in key equipment performance are *** study indicates that the inter-stage cooling and recompression cycle has the best match with the heat source characteristics of the SFR,and the cycle efficiency is the highest(40.7%).Then,based on the developed system transient analysis program(FR-Sdaso),a pool-type SFR power plant system analysis model based on the inter-stage cooling and recompression cycle is *** addition,the matching between the inter-stage cooling recompression cycle and the SFR during the load cycle of the power plant is *** analysis shows that when the nuclear island adopts the flow-advanced operation strategy and the carbon dioxide flowrate in the SCO_(2) power conversion system is adjusted with the goal of maintaining the sodium-carbon dioxide heat exchanger sodium side outlet temperature unchanged,the inter-stage cooling recompression cycle can match the operation of the SFR very well.

关键词： sodium-cooled fast reactor(SFR) supercritical carbon dioxide(SCO_(2)) brayton cycle load cycle

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Solute clusters-promoted strength-ductility synergy in Al-Sc alloy

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Journal of Materials Science & Technology 2022年第1期96卷 325-331页

作者： chong yang Pengming Cheng Baoan Chen Jinyu Zhang Gang Liu jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Advanced Power Transmission Technology Global Energy Interconnection Research Institute Co.Ltd.Beijing 102209China

Sc solute clusters with a high number density were produced in an Al-0.3 wt.%Sc alloy when aged at250℃,while fine Al_(3)Sc precipitates were predominantly formed in the same alloy aged at 300℃.The alloy strengthened by Sc solute clusters displayed higher yield strength and simultaneously greater ductility than its counterpart strengthened by Al_(3)Sc *** clearly demonstrates a superior strengthductility synergy promoted by the Sc solute clusters in Al-Sc *** effects of Al_(3)Sc precipitates and Sc solute clusters on ductility were discussed in comparison by using a micromechanics fracture *** the Sc clusters were stabilized at 250℃,the Al-Sc alloys strengthened by Sc solute clusters should find extensive application fields within a wide temperature range,due to their high temperature resistance.

关键词： Al-Sc alloy Solute clusters Strength Ductility Micromechanics model

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Highly efficient nanocatalyst Ni1Co9@graphene for hydrolytic dehydrogenation of sodium borohydride

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International Journal of Minerals,Metallurgy and Materials 2021年第12期28卷 1976-1982页

作者： Juan Wang Li-jun yang Xiao-chong Zhao Pan yang Wei Cao Qing-song Huang School of Chemical Engineering Sichuan UniversityChengdu 610065China Institute of Materials Chinese Academy of Engineering PhysicsJiangyou 621908China

Bimetal materials derived from transition metals can be good catalyst candidates towards some specific *** loaded on graphene(GP),these catalysts exhibit remarkable performance in the hydrolysis of sodium *** obtain such catalysts easily and efficiently,a simple thermal reduction strategy was used in this study,and Ni_(x)Co_(10-x) series bimetal catalysts were *** all the catalysts,Ni_(1)Co_(9) exhibited the best catalytic *** turnover frequency(TOF)related to the total number of atoms within the bimetallic nanoparticles reached 603.82 m L·mmol^(-1)·min^(-1) at 303 ***,graphene was introduced as a supporting *** Ni1Co9@Graphene(Ni1Co9@GP)had a large surface area and high TOF,25534 mL·mmol^(-1)·min^(-1),at 303 *** Ni_(1)Co_(9)@GP exhibited efficient catalytic properties for H2 generation in alkaline solution because of its high specific surface ***,the high kinetic isotope effect observed in the kinetic studies suggests that using D2O led to the oxidative addition of an O-H bond of water in the rate-determining step.

关键词： catalyst Highly hydrolysis

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Two 8-node quadrilateral spline elements by B-net method

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Acta Mechanica Sinica 2012年第6期28卷 1620-1629页

作者： Juan Chen chong-jun Li School of Mathematics and Quantitative Economics Dongbei University of Finance and Economics School of Mathematical Sciences Dalian University of Technology

Isoparametric quadrilateral elements are widely used in the finite element method, but the accuracy of the isoparametric quadrilateral elements will drop obviously deteriorate due to mesh distortions. Spline functions have some properties of simplicity and conformality. Two 8-node quadrilateral elements have been developed using the trian- gular area coordinates and the B-net method, which can ex- actly model the quadratic field for both convex and concave quadrangles. Some appropriate examples are employed to evaluate the performance of the proposed elements. The nu- merical results show that the two spline elements can obtain solutions which are highly accurate and insensitive to mesh distortions.

关键词： Spline finite element B-net method Quadri-lateral element - Bivariate spline interpolation The secondorder completeness

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Development of quadrilateral spline thin plate elements using the B-net method

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Acta Mechanica Sinica 2013年第4期29卷 567-574页

作者： Juan Chen chong-jun Li School of Mathematics and Quantitative Economics Dongbei University of Finance and Economics School of Mathematical Sciences Dalian University of Technology

The quadrilateral discrete Kirchhoff thin plate bending element DKQ is based on the isoparametric element Q8, however, the accuracy of the isoparametric quadrilateral elements will drop significantly due to mesh distortions. In a previous work, we constructed an 8-node quadrilateral spline element L8 using the triangular area coordinates and the B- net method, which can be insensitive to mesh distortions and possess the second order completeness in the Cartesian co- ordinates. In this paper, a thin plate spline element is devel- oped based on the spline element L8 and the refined tech- nique. Numerical examples show that the present element indeed possesses higher accuracy than the DKQ element for distorted meshes.

关键词： Spline finite element ~ Refined quadrilateral el-ement ~ Discrete Kirchhoff plate element ~ Triangular areacoordinates ~ B-net method

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