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Land use change and its ecological effect in Qian’an County of Jilin Province

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Journal of Geographical sciences 2003年第4期 41-46页

作者： Karl e.Ryavec Department of Geography MN55455 UsA University of Minnesota

Based on GIs and statistical methods, with the help of searching historical literatures andcalculating the landscape indices, the land use changes of Qian’an County in both spatial and temporalaspects from 1945 to 1996 has been analyzed in this paper. And the driving forces of land use changesand their ecological effects are discussed too. The main findings of this study are as follows:(1)Landuse changed greatly in Qian’an during 1945-1996, characterized by a decrease in grassland, wetlandand water bodies,and an increase in cultivated land, saline-alkali land, and the land for housing andother construction purposes. Grassland decreased by 175,828.66 ha, and cultivated land increased by

关键词： land use change ecological effect land degradation Qian’an County

Degradation of nitrobenzene in wastewater by γ-ray irradiation

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Journal of environmental sciences 2004年第3期16卷 364-366页

作者： ZHANG shu juan 1, FeNG shao hong 1, YU Han qing 1,* , LI Qian rong 2 (1 Department of Chemistry, University of science & Technology of China, Hefei 230026, China. 2 Research Center for Physics & Chemistry, University of science & Technology of China, Hefei 230026, China) Department of Chemistry University of Science & Technology of China Hefei 230026 China Research Center for Physics & Chemistry University of Science & Technology of China Hefei 230026 China

The degradation of nitrobenzene(NB) by γ ray irradiation was studied. The influences of dose rate and initial NB concentration were investigated in details. At a dose rate of 55 Gy/min, the degradation kinetics was pseudo first order at NB concentrations from 0 2 mmol/L to 4 0 mmol/L. At an initial NB concentration of 0 8 mmol/L, the degradation of NB at various dose rates also followed pseudo first order kinetics. Dissolved oxygen was found to have a positive effect on NB degradation. The degradation products were identified as nitrophenol, nitrosobenzene, and hydroquinone, and so on. Based on the product analysis, possible degradation pathways of nitrobenzene were proposed.

关键词： degradation irradiation nitrobenzene(NB) kinetics

Chapter 1 Before Breakfast (excerpt) 第一章早饭前（节选）

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Automatic segmentation of Moving Objects in Video sequences for Indoor and Outdoor Applications

疯狂英语·新悦读 2024年第7期 43页

作者： e.B.White

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The Journal of China Universities of Posts and Telecommunications 2003年第4期10卷 76-81页

作者： FALAH e. ALsAQRe Institute of Information science Beijing Jiaotong University

Computer vision systems have an impressive spread both for their practicalapplication and for theoretical research . The common approach used in such systems consists of agood segmentation of moving objects from video sequences . This paper presents an automaticalgorithm for segmenting and extracting moving objects suitable for indoor and outdoor videoapplications, where the background scene can be captured beforehand . since edge detection is oftenused to extract accurate boundaries of the image's objects, the first step in our algorithm isaccomplished by combining two edge maps which are detected from the frame difference in twoconsecutive frames and the background subtraction . After removing edge points that belong to thebackground, the resulting moving edge map is fed to the object extraction step . A fundamental taskin this step is to declare the candidates of the moving object, followed by applying morphologicaloperations. The algorithm is implemented on a real video sequence as well as MPeG- 4 sequence andgood segmentation results are achieved.

关键词： frame difference background subtraction moving object segmentation cannyedge detection morphological operation

Reiterated homogenization of a laminate with imperfect contact:gain-enhancement of effective properties

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Applied Mathematics and Mechanics(english edition) 2018年第8期39卷 1119-1146页

作者： F.e.ALVAReZ-BORGes J.BRAVO-CAsTILLeRO M.e.CRUZ R.GUINOVART-DIAZ L.D.PeReZ-FeRNANDeZ R.RODRIGUeZ-RAMOs F.J.sABINA Facultad de Matematica y Computacion Departamento de MatematicaUniversidad de La HabanaSan Lazaro y LHabana 4La HabanaCP 10400Cuba Departamento de Matematicas y Mecanica Universidad Nacional Autonoma de MexicoInstituto de Investigaciones en Matematicas Aplicadas y en Sistemas01000 CDMXAP 20-126M′exico Departamento de engenharia Mecanica Universidade Federal do Rio de JaneiroPolitecnica/COPPECaixa Postal 68503Rio de JaneiroRJCEP 21941-972Brasil Departamento de Matematica e estatistica Universidade Federal de PelotasCaixa Postal 354PelotasRio Grande do SulCEP 96010-900Brasil

A family of one-dimensional(1D) elliptic boundary-value problems with periodic and rapidly-oscillating piecewise-smooth coefficients is considered. The coefficients depend on the local or fast variables corresponding to two different structural scales. A finite number of imperfect contact conditions are analyzed at each of the scales. The reiterated homogenization method(RHM) is used to construct a formal asymptotic solution. The homogenized problem, the local problems, and the corresponding effective coefficients are obtained. A variational formulation is derived to obtain an estimate to prove the proximity between the solutions of the original problem and the homogenized problem. Numerical computations are used to illustrate both the convergence of the solutions and the gain of the effective properties of a three-scale heterogeneous 1D laminate with respect to their two-scale counterparts. The theoretical and practical ideas exposed here could be used to mathematically model multidimensional problems involving multiscale composite materials with imperfect contact at the interfaces.

关键词： reiterated homogenization method(RHM) imperfect contact variational formulation effective coefficient gain

TLR3 Ligand-Induced Accumulation of Activated splenic Natural Killer Cells into Liver

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Cellular & Molecular Immunology 2005年第6期2卷 449-453页

作者： Jing Wang~1 Jiawei Xu~1 Weici Zhang~1 Haiming Wei~1 Zhigang Tian~(1,2) ~1Institute of Immunology,school of Life sciences,University of science and Technology of China,Hefei,Anhui,China ~2Institute of Immunology,school of Life sciences,University of science and Technology of China,443 Huangshan Road,Hefei 230027,Anhui,China. Institute of Immunology School of Life Sciences University of Science and Technology of China Hefei Anhui China

It has been revealed that poly I：C is a potent stimulator for NK cells, which can induce NK cell rapid activation and preferential accumulation into liver. However, the process mediating the influx of NK cells remains obscure. In this study, we found that poly I：C administration increased the portion and absolute number of NK cells in liver, but largely decreased those in spleen. There were no obvious changes of these lymphocytes in other immune organs. The results from splenic adoptive transfer and splenectomy showed that the recruited spleen NK cells contributed to the accumulation of NK cells in liver, and this process was regulated by the production of chemokines and the presence of T cells. This investigation will help to understand the enhanced immune cell recruitment in liver upon viral infection. Cellular ＆ Molecular Immunology. 2005;2（6）：449-453.

关键词： liver spleen NK poly I:C recruitment

Investigation on Technique for ethylene Preparation via Catalyzed in Fluidized Bed Dehydration of Bioethanol

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China Petroleum Processing & Petrochemical Technology 2009年第4期11卷 38-41页

作者： Liu Kewei~(1,2) Yan Guiyang~1 Hong Aizhu~(1,2) Xiao Junfeng~(1,2) Xiao Liren~(1,2) Chen Qinghua~(1,2) (1.College of Chemistry and Materials science,Fujian Normal University,Fuzhou 350007 2.Fujian Modified Plastic Research & Development Technology Base) College of Chemistry and Materials science Fujian Normal University Fuzhou 350007 China Fujian Modified Plastic Research and Development Technology Base China

The V-P/HZsM-5 catalyst was prepared by impregnation method using HZsM-5 zeolite as the *** catalytic activity was examined on dehydration of bio-ethanol in a self-designed fluidized bed reactor to manufacture ethylene. The effects of dehydration conditions on catalytic behaviors were *** results showed that the V-P/HZsM-5 catalyst demonstrated good activity for bio-ethanol *** bio-ethanol conversion and ethylene selectivity were over 90%under the following reaction conditions:a P/V atomic ratio of 7.5,a catahst calcination temperature of 300℃,a reaction temperature of 220℃,a bio-ethanol flow rate of 0.1 mL/*** a catalyst dosage of 3.0 ***,the catalyst exhibited excellent catalytic stability and regeneration capability.

关键词： biology ethanol V-P/HZsM-5 fluid bed dehydration ethylene

Narrowband imaging method for spatial precession cone-shaped targets

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science China(Technological sciences) 2010年第4期53卷 942-949页

作者： DING XiaoFeng1,FAN MeiMei1,WeI XiZhang1,LI Xiang1 & Xiao HuaiTie2 1 Institute of space electronics Information Technology,National University of Defense Technology,Changsha 410073,China 2 school of electronic science and engineering,National University of Defense Technology,Changsha 410073,China Institute of space electronics Information Technology National University of Defense Technology school of electronic science and engineering National University of Defense Technology

The imaging method of the mid-course missile is the key technique of the missile defense *** of the special precession character of the ballistic missile warhead,the inverse synthetic aperture radar method cannot realize phase compensation with the constant phase offset function,which leads to blurring of the *** this paper,we propose a new narrowband radar imaging method for the precession cone-shaped *** method acquires the Doppler modulation of the precession target's scattering centers with high resolution time-frequency analysis method and extracts the Doppler parameter from the result of the time-frequency analysis with the general Radon transform,then reconstructs the scattering centers positions in the parameter *** experiment results with the anechoic chamber data of the representative cone-shaped object showed the effectiveness of the method.

关键词： narrowband radar imaging time-frequency analysis general Radon transform

Hybrid microsystem with functionalized silicon substrate and PDMs sample operating microchannel: A reconfigurable microfluidics scheme

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science China(Technological sciences) 2010年第8期53卷 2272-2277页

作者： LeI YinHua 1 ,XIe Fei 1 ,WANG Wei 1,2 ,WANG HaiBin 3 &LI ZhiHong 1,2 1 Institute of Microelectronics,Peking University,Beijing 100871,China 2National Key Laboratory of science and Technology on Micro/Nano Fabrication,Beijing 100871,China 3 No.302 Hospital,Beijing 100039,China Institute of Microelectronics Peking University National Key Laboratory of science and Technology on Micro/Nano Fabrication

A hybrid microsystem with separately functioned temperature controlling substrate and sample operating fluidic microchannel was developed to demonstrate a reconfigurable microfluidics *** temperature controlling substrate integrated a micro heater and a temperature sensor by using traditional silicon-based micromechanical system(MeMs)technique,which guaranteed high performance and robust reliability for repeatable *** sample operating fluidic microchannel was prepared by poly-(dimethylsiloxane) (PDMs)based soft lithography technique,which made it cheap enough for disposable *** PDMs microchannel chip was attached to the temperature controlling substrate for reconfigurable thermal applications.A thin PDMs film was used to seal the microchannel and bridge the functionalized substrate and the sample inside the channel,which facilitated heat transferring and prevented sample contaminating the temperature controlling *** by a one dimensional thermal resistance model,the thin PDMs film was important for the present reconfiguration *** performance of this hybrid microsystem was examined,and the experimental results demonstrated that the chip system could work stably over hours with temperature variation less than *** PDMs microchannel chips were tested on one heating substrate sequentially with a maximum intra-chip temperature difference of *** extracted from serum of a chronic hepatitis B virus(HBV)patient was amplified by this hybrid microsystem and the gel electrophoresis result indicated that the present reconfigurable microfluidic scheme worked successfully.

关键词： reconfigurable microfluidics hybrid microdevice thin PDMs film