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Can Cadmium Uptake by Chinese Cabbage be Reduced After Growing Cd-Accumulating Rapeseed?

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Pedosphere 2010年第1期20卷 90-95页

作者： SU De-Chun , JIAO Wei-Ping, ZHOU Man and CHEN Xia College of Resources and Environmental Sciences, china Agricultural university, beijing 100193.(china) [a] College of Resources and Environmental Sciences China Agricultural University Beijing 100193 (China)

Rapeseed （Brassica campestris L.）, a Cd-accumulating crop, is effective in reducing plant-available Cd from soil. A pot experiment was conducted to test the hypothesis that the Cd uptake by Chinese cabbage （Brassica pekinensis Rupr.） grown in rotation with rapeseed would be reduced due to the efficient removal of bioavailable Cd from soil solution by the rapeseed crops. The Cd removal by shoot for the rapeseed cultivar Zhucang Huazi ranged from 0.24% to 0.99% in natural Cd-contaminated soil （soil A） and from 0.63. to 1.23. in artificial Cd-contaminated soil （soil B） during the growth period of 4 7 weeks; whereas that for the rapeseed cultivar Chuanyou Ⅱ-93.ranged from 0.25% to 0.66% and from 0.3.% to 1.02%, respectively. Chinese cabbage grown in the pots with soil A for five weeks after harvesting rapeseed exhibited a significantly lower Cd concentration compared to that grown in the control pots （uncropped with rapeseed）. However, the rotation of rapeseed did not lower the Cd concentration of Chinese cabbage on soil B. Although an increase of Cd uptake was observed in the rapeseed cultivars with growth time, and the decrease of soil NH4OAc-extractable Cd was found only in the natural rather than artificial Cd-contaminated soil.

关键词： Cd-contaminated soil crop rotation heavy metal phytoremediation plant-available Cd

A Graph Theoretic Method to Handle Deadlocks in Flexible Manufacturing Cells

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武汉理工大学学报 2006年第S3期28卷 1117-1120页

作者： WANG Chunxiang~(1,2) LIU Donglin~3.(1.School of Mathematics and Statistics,Wuhan university,Wuhan 43.072,china, 2.School of Mathematics and Statistics,Central china Normal university,Wuhan 43.079,china 3.School of Electronic and Mechanical Engineering,Wuhan university of Technology,Wuhan 43.070,china) School of Mathematics and Statistics Wuhan UniversityWuhan 430072China School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China School of Electronic and Mechanical Engineering Wuhan University of TechnologyWuhan 430070China

The deadlock-handling scheme is based on a bipartite graph model of the part-machine relationship in the manufac- turing cell.A distinction is made between permanent deadlock and transient *** deadlock depicts a manufactur- ing system state where parts are irrevocably blocked and where external intervention is required to resolve the deadlock,whereas a transient deadlock indicates that there is a positive probability that the deadlock will resolve itself over *** recover from dead- locks,one control policy is studied:resolve deadlocks in the manufacturing *** the policy,it is shown that it is sufficient to resolve any cycle in the set of deadlocked parts to resolve the ***,we estimate the deadlocks in flexible manufactur- ing cells.

关键词： permanent deadlock transient deadlock deadlock detection deadlock resolution graph

A Perceptual Contour Linking Approach for Clumped Live Cell Image Segmentation

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A Perceptual Contour Linking Approach for Clumped Live Cell ...

The First International Congress of Medical Imaging and Interventional Medicine

作者： Hui-lin Chen Li ZhangDepartment of Electronic Engineering tsinghua university beijing 100084 {3.

＜正＞ In this paper, an edge-based approach is proposed to segment the clumped live unstained cells, which can be characterized as of being intensity-variant, shape-irregular, and boundary-disturbed To achieve this, we present a perceptual contour linking approach based on the Gestalt laws of closure, continuity and simplicity to extract the contours. Three types of fragments are generalized from the edge map of cell images and then a series of templates are developed to guide the contour Unking while the growth length defined on confidence guarantees the recognition process resembling human vision. The approach is tested on the clumped live unstained cell images and encouraging results are obtained.

关键词： Cell image segmentation Perceptual contour Edge linking

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儿童早期数学认知能力的结构及其特点

心理学报 2003年第6期35卷 810-817页

作者：张华庞丽娟陶沙陈瑶董奇北京大学心理学系北京10087 北京师范大学教育学院北京100875 北京师范大学心理学院北京100875

从北京市 1 0所幼儿园中选取 2 3.名 3.4岁的儿童为被试 ,采用个别测查的方法对儿童早期数学认知能力的结构及其特点进行了考察。经验证性因素分析发现 :(1 )儿童早期数学认知能力的结构模型是合理的 ,可接受的 ,具有较好的构想效度 ,... 详细信息

从北京市 1 0所幼儿园中选取 2 3.名 3.4岁的儿童为被试 ,采用个别测查的方法对儿童早期数学认知能力的结构及其特点进行了考察。经验证性因素分析发现 :(1 )儿童早期数学认知能力的结构模型是合理的 ,可接受的 ,具有较好的构想效度 ,具体讲 ,数、计算、测量、空间 /几何和模式认知能力五个维度共同解释着儿童早期的数学认知能力 ;(2 )不同年龄儿童早期数学认知能力的结构具有稳定性 ,但是结构模型并不完全一致 ,某些项目的解释率有所不同 ;(3.男。

关键词：早期数学认知能力结构模型验证性因素分析

Compound Preparation Technology of Semi-solid Slurry Based on Stirring Method

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Compound Preparation Technology of Semi-solid Slurry Based o...

Up-Embeddability of Graphs with New Degree-Sum of Independent Vertices

第十届全国塑性工程学术年会、第三届国际塑性加工先进技术研讨会

作者： MI Guang-bao LI Pei-jie (Department of Mechanical Engineering,tsinghua university,beijing 100084,china)

Stirring method is one of the most effective ways to fragmentate the alloy melt *** 3. years' development, a lot of processes of preparing slurry have been derived,but the existent defects in such processes restrict their widespread *** compound preparation technology based on stirring method is the process combination which exerts visible or invisible shearing function on solidifying melt,meanwhile,optimizes now available single process or intensively combines couple or more processes in time and space,so as to make the distribution of temperature and density fields trend to be homogenous to obtain fine round non-dendritic *** technology is an important development direction of obtaining ideal semi-solid microstructure continuously and stably,which already has been concerned by researchers at home and abroad presently.

关键词： stirring method compound preparation technology optimized process intensive combination ideal non-dendrite

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Journal of Mathematical Research with Applications 2012年第4期32卷 399-406页

作者： Shengxiang L1, , Yanpei LIU 2 1. Department of Mathematics, Hunan university of Science and Technology, Hunan 411201, P. R. china 2. Department of Mathematics, beijing Jiaotong university, beijing 100044, P. R. china. Department of Mathematics Hunan University of Science and Technology Hunan 411201 Department of Mathematics Beijing Jiaotong University Beijing 100044

Let G be a k(k ≤3.-edge connected simple graph with minimal degree ≥ 3.girth g,r=*** any independent set {a1,a2 , . . . , a 6/(4 k)} of G,if,then G is up-embeddable.

关键词： up-embeddability maximum genus independent set

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分支结构中的虚拟内窥技术

系统仿真学报 2004年第11期16卷 2456-2458,2466页

作者：申皓唐泽圣唐龙清华大学计算机科学与技术系北京100084

介绍了完整的面向具有树状分支结构特征的管道系统的虚拟内窥技术。以典型的具有树状分支结构特征的支气管为例,从如何进行人体体数据的分割及三维模型的重建开始,依次介绍了如何利用三维图像细分算法提取虚拟漫游的主路径,如何根据漫... 详细信息

介绍了完整的面向具有树状分支结构特征的管道系统的虚拟内窥技术。以典型的具有树状分支结构特征的支气管为例,从如何进行人体体数据的分割及三维模型的重建开始,依次介绍了如何利用三维图像细分算法提取虚拟漫游的主路径,如何根据漫游路径重新组织复杂的三维模型,随后介绍了一种用于管道内部漫游的碰撞检测方法——位置-体素对照表法,最后介绍了在具有分支结构特征的管道系统中的视点导航技术。

关键词：分支结构虚拟内窥路径提取碰撞检测漫游导航

Comparison of Concrete Carbonation Process under Natural Condition and High CO_2 Concentration Environments

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Journal of Wuhan university of Technology(Materials Science) 2010年第3期25卷 515-522页

作者：姬永生 State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology Xuzhou School of Mechanics & Civil Engineering China University of Mining and Technology Xuzhou

To compare the results obtained under both natural and accelerated environments,the pH values of carbonated concrete were measured,the variation of pH values was determined,and the variations of Ca（OH）2 and CaCO3.contents in the carbonated concrete under natural condition and high CO2 concentration accelerated climate environments were determined by microcosmic test methods such as DTA and X-ray *** experimental results showed that the overall variation trend of pH values and phase component of carbonation layer of concrete under accelerated climate environments with high CO2 concentrations were the same as those under natural ***,the carbonation processes of concrete were considered consistent under both *** there was a difference in the length of semi-carbonation *** one measured under high CO2 concentration accelerated climate environments was shorter than that under natural *** investigation showed that it was caused by the differences in climate condition（temperature and relative humidity） as well as the properties of the *** concentration of CO2 and the duration of the carbonation process have no effect on the length of semi-carbonation ***,it is acceptable to simulate the natural condition by applying the high CO2 concentration artificial accelerated carbonation technique for the purpose of the study of carbonation process of concrete.

关键词： natural carbonation artificial accelerated carbonation phase component semi carbonation zone correlation

Montgomery Multiplier Based on Secondary Booth Encoded Algorithm

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Montgomery Multiplier Based on Secondary Booth Encoded Algor...