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Carbon isotopic composition,turnover and origins of soil CO2 in a monsoon evergreen broadleaf forest in the Dinghushan Biosphere Reservoir,South china

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science Bulletin 2010年第23期55卷 2551-2559页

作者： DING Ping1,SHEN ChengDe1,2,WANG Ning1,YI WeiXi1,DING XingFang2,FU DongPo2,LIU KeXin2 & ZHAO Ping3 1Key laboratory of Isotope Geochronology and Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of sciences,Guangzhou 510640,china 2State Key laboratory of Nuclear Physics and technology,Peking university,Beijing 100871,china 3South china Botanical Garden,Chinese Academy of sciences,Guangzhou 510650,china

Carbon isotopic compositions of soil CO2 in rainy season (July) from two natural soil profiles (DHLS & DHS) in the monsoon evergreen broadleaf forest in the Dinghushan Biosphere Reservoir (DBR),South china,are *** and origins of soil CO2 are preliminarily discussed in this *** show that the content of soil CO2 varies between 6120 and 18718 ppmv,and increases with increasing depth until 75 cm,and then it *** DHLS,soil CO2 δ 13C ranges from -24.71‰ to -24.03‰,showing a significant inverse correlation (R2=0.91) with the soil CO2 content in the same *** to a model related to soil CO2 δ 13C,the soil CO2 is mainly derived from the root respiration (>80%) in *** in DHS,where soil CO2 δ 13C ranges from -25.19‰ to -22.82‰,soil CO2 is primarily originated from the decomposition of organic matter (51%–94%),excluding the surface layer (20 cm,90%).Radiocarbon data suggest that the carbon in soil CO2 is modern carbon in both DHLS and *** in 14C ages between the "oldest" and "youngest" soil CO2 in DHLS and DHS are 8 months and 14 months,respectively,indicating that soil CO2 in DHLS has a faster turnover rate than that in *** Δ14C values of soil CO2,which range between 100.0‰ and 107.2‰ and between 102.5‰ and 112.1‰ in DHLS and DHS,respectively,are obviously higher than those of current atmospheric CO2 and SOC in the same layer,suggesting that soil CO2 is likely an important reservoir for Bomb-14C in the atmosphere.

关键词： Dinghushan Biosphere Reservoir soil CO2 turnover Bomb-14CO2 13C & 14C

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A new method to evaluate imaging quality of CCD cameras

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Optoelectronics Letters 2005年第2期 72-74页

作者： LI Wen-juan-(1,2), DU Hai-hui-3, DAI Jing-min-1,and CHEN Ying-hang-3 1.School of Electrical Engineering & Automation,Harbin Institute of technology,Harbin 150001,china 2.Electrical & Electronic Engineering College,Harbin university of science and technology,Harbin 150040,china 3.303 Institute of No.3 research Academe of china Aerospace science & Industry Corporation,Beijing 100074, china

In order to evaluate the imaging quality of CCD cameras fully and rapidly,the minimum resolvable contrast (MRC) is presented in this paper and the system of measuring MRC is constructed as well,in which two integrating spheres are proposed to illuminate two sides of the target *** variable contrast can be obtained by regulating the luminance of integrating spheres. Experimental results indicate that the error of measuring luminance is within ±0.3 cd/m-2,MRC rises with the increase of the spatial *** experimental results show that the method proposed is an effective approach to evaluate the imaging quality of CCD cameras.

关键词： CCD

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Adaptive generation of hexahedral element meshes for finite element analysis of metal plastic forming process

Adaptive generation of hexahedral element meshes for finite ...

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The 18th International Symposium on Computational Mechanics of Materials

作者： Zhang Hongmei~1 Zhao Guoqun~2 1.School of Material science and Engineering Beijing Institute of technology Beijing 100081 china 2.Engineering research Center for Mould & Die Technologies Shandong university Jinan Shandong 250061 china

＜正＞The quality of finite element mesh is one of the important factors which determine the precision and accuracy of finite element analysis,especially in the large metal *** is crucial for the generated meshes to exactly describe all the features of the analyzed solid *** a method for the adaptive generation of hexahedral element mesh based on the geometric features of solid model is *** is based on the conventional grid-based method and geometry-adaptive technique to generate uniformly sized or locally refined hexahedral *** first step is to construct the refinement information fields of source points and the corresponding ones of elements according to the surface curvature of the analyzed solid model.A thickness refinement criterion is then used to construct the thickness-based refinement information field of elements from digital ***, the element refinement fields are integrated and modified according to the conformal refinement templates proposed in this paper, and used as a metric to generate an initial grid structure enveloping the solid model *** order to ensure the conformity of the generated mesh,a set of new refinement templates are proposed,and the corresponding modes for converting arbitrary refinement field to the templates is *** third step is to generate a core mesh through removing all the undesired elements using even and odd parity *** the core mesh is magnified in an inside-out manner through a surface node projection process using the closest position *** match the mesh to the characteristic boundary of the solid model,a minimal Scaled Jacobian criterion is ***,in order to handle the degenerated elements and improve the quality of the resulting mesh,two comprehensive techniques are employed:the insertion technique and collapsing *** present method was applied in the mesh construction of different engineering problems. Scaled Jacobian and Skew m

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Influence of Acetic Acid on Dynamic Behavior of Hydrolazation and Film Forming of Organosilane

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Journal of Wuhan university of technology(Materials science) 2009年第4期24卷 546-551页

作者：杨丽霞 School of Materials Chemistry and Engineering China University of Geosciences

The influence of acetic acid on dynamic behavior of hydrolazation and film forming of an expoxy-silane compound （y-GPS） was investigated by conductivity meter, IR and AFM. The experimental results show that there is an optimal pH value（pH=4-5） for hydrolysis of silane solution, and with the prolongation of hydrolytic time, the promotion of acetic acid on the hydrolyzation of silane solution become more obvious. During the adsorption and film forming process, acetic acid could promote the formation of Si-O-Fe bond, which activates hydroxyl group of silanol unit and facilitates this hydroxyl group to react with adjacent silanol unit forming linear condensation polymers.

关键词： organosilane hydrolyzation film forming acetic acid

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On the Management of the College Capital Construction Archive

On the Management of the College Capital Construction Archiv...

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2010 International Conference on Semiconductor Laser and Photonics (ICSLP 2010)

作者： Limei Liu Archives Hebei Normal university of science & technology Qinhuangdao Hebei china

This paper discusses how to manage college capital construction archives in accordance with the archive collection ＆ arrangement and exploitation in light of the problems in the management of college capital construc... 详细信息

关键词： college capital construction archive collection & arrangement exploitation.

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A research OF UWB RAKE RECEIVER BASED ON NOVEL RLS ADAPTIVE ALGORITHM

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Journal of Electronics(china) 2006年第3期23卷 341-345页

作者： Yin Yong Yu Nenghai Dong Weijie MOE-Microsoft Key laboratory of Multimedia Computing and Communication Information Processing Center University of Science and Technology of China Hefei 230027 China

A modified RAKE receiver based on novel Recursive Least Squares （RLS） adaptive algorithm is proposed. The receiver uses L-fingered correlators, which are composed of RLS adaptive filters, to enhance the performance of multipath receiving. It can also track the amplitude of the received signal to form a real-time amplitude estimation which is correlated with the power of excess delay bin. The simulation results based on the IEEE UltraWide Band （UWB） channel models （CMI to CM4） show that the novel RLS algorithm can alter the attenuation estimation with the finger＇s power delay profile, and RAKE receiver with few fingers can be employed to get high performance.

关键词： UltraWide Band (UWB) RAKE receiver Recursive Least Squares (RLS)

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Analysis and confirm of anabolic steroids in urine by GC/MS

Analysis and confirm of anabolic steroids in urine by GC/MS

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30th International Symposium on Capillary Chromatography、4th GC×GC Symposium、16th National Symposium and Exhibition on Chromatography,i.e. 1st Dalian International Symposium and Exhibition on Chromatography

作者： Liangmin Shangguan Wei Liu Qiaomei Lu Lan Zhang~* Guonan Chen The Ministry of Education Key laboratory of Analysis and Detection technology for Food Safety(Fuzhou university),china The Sport science research Center,Fuzhou university,Fuzhou,Fujian,350002,china

＜正＞Anabolic steroids are currently a class of abused *** of their anabolic effects,they can enhance nitrogen retention and build-up of proteins result in improved muscle ***,based upon results of pharmacological and toxicological studies,they are harm to *** use of anabolic steroids in sports had been banned by the International Olympic Committee（IOC）since ***,detection of anabolic steroid misuse continues to be a significant fraction of the workload in athletic drug testing laboratories.

关键词： Anabolic steroids LLE Derivatization GC/MS

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Study of Real-Time Detecting Algorithm on Eddy Current Nondestructive Testing

Study of Real-Time Detecting Algorithm on Eddy Current Nonde...

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第一届国际测量仪器与测试自动化学术会议

作者： Liu Donghui Yang Guofu (Hebei university of science & technology Shijiazhuang 050054 china)

＜正＞Immune Radial Basis Function （IRBF） networks are applied to real-time online detecting systems. After completing the Eddy Current Nondestructive quantitative detecting （ECNDT） using classical RBF method, authors put forward using immune algorithms to optimize the network structure, and using the Recursive Least Squares （RLS） algorithm to estimate weight vector. The comparison shows that the network structure is simplified strongly while computation is reduced greatly This method can be applied online.

关键词： IRBF network ECNDT RLS immune algorithm.

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Robust Admissibilization for a Class of Discrete Singular Systems

Robust Admissibilization for a Class of Discrete Singular Sy...

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第三十一届中国控制会议

作者： HE Guannan~1 JI Jing~2 YU Wensheng~3 1.College of Information science and technology Beijing university of Chemical technology Beijing 100029 P.R.china 2.School of Information Engineering Guangdong university of technology Guangzhou 510006 Guangdong P.R.china 3.Shanghai Key laboratory of Trustworthy Computing East china Normal university Shanghai 200062 P.R.china

＜正＞In this paper,we investigate the robust admissibilization problem for a class of discrete singular *** on the Lyapunov stability theory,some sufficient and necessary conditions,which guarantee the nominal system to be admissible, are derived in terms of linear matrix inequalities（LMIs）.Furthermore,applying the parameter dependent Lyapunov function approach,the robust admissibilization stabilization conditions via state feedback are also presented.A numerical example is given to demonstrate the effectiveness of the proposed methods.

关键词： Robust Admissibilization Discrete-time Singular systems Linear matrix inequality(LMI)

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The structure and Activities of Inter-organizational Knowledge Sharing Chain and Network

The Structure and Activities of Inter-organizational Knowled...

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2011 3rd IEEE International Conference on Information Management and Engineering(ICIME 2011)

作者： Xiangyang Qing School of Economics and Management Southwest university of science and technology Sichuan china

The present article aims to provide a theoretical foundation for the evaluation and categorization of the knowledge domain of Chain and Network science（CNS）.It aims to clarify what the field of CNS includes and to investigate where we stand in developing *** elaborates on a number of important theories that provide insight in the structure and activities of actors in chains and networks,and discusses the key issues that are raised by each *** concludes by suggesting some important research questions in the field of CNS,integrating the different theoretical perspectives,and touching upon a number of management challenges for the years to come.

关键词： Chains networks inter-organizational

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