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Monitoring of rice crop using ENVISAT ASAR data

Science China Earth Sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. SUN Guoqing1,3 & PANG Yong4.1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 100101, China 2. Graduate university of Chinese Academy of Sciences, Beijing 100039, China 3. department of {2., university of Maryland, College Park, MD 2.74.0} USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, Chinese Academy of For-estry, Beijing 100091, China 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate university of Chinese Academy of Sciences Beijing 100039 China 3. department of geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

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N,N-Di-isopropyl-O,O-Di-p-methoxybenzylphosphoramidite——A New Phosphorylating Reagent

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Chinese Chemical Letters 1999年第9期10卷 719-722页

作者： Shoichirol OZAKI Ai You HAO Xiang Zheng KONG Da Xing ZHENG(department of Chemistry, Shandong university, {2. 2.0100) Shandong Univ Dept Chem Jinan 250100 Peoples R China

A new phosphorylating reagent, N,N-di-isopropyl-O,O-di-p-methoxybenzylphosphoramidite was synthesized from diisopropylamino dichlorophosphine and p-methoxybenzyl alcohol for preparing phosphatydyl inositol polyphospha... 详细信息

关键词： N,N-di-isopropyl-O,O-di-p-methoxybenzylphosphoramidite phophorylating reagent unsaturated component

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The Stamping Formability of AZ31 Magnesium Alloy Sheet Improved by Equal-channel Angular Pressing

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 234-237页

作者：刘英 department of Material Science and Engineering Jinan University

Equal channel angular pressing （ECAP） processing and annealing were applied to the AZ31 magnesium alloy sheets to evaluate the potential improvement in the mechanical properties and formability. The ECAP experiment was conducted at 300 ℃ in a die having an included angle of 90o between two channels by the BCZ route with the sheets rotated by 90°about the normal axis of plate plane. The tensile tests and conical cup tests were conducted at various temperatures from 2. to 2.0 ℃. The experimental results indicated that improving the working temperatures could lead to the soft in the material and the enhancement of ductility. Comparatively, the ECAPed AZ31 alloy sheets showed the lower yield strength and smaller conical cup value （CCV） than the unECAPed counterpart in the room temperature. The difference in yield strength between them became small in the elevated temperature, but the ECAPed samples still had the smaller CCV value, implying the improved formability. The texture of the AZ31 alloy sheets could be modified by ECAP and the decrease in the yield strength and more uniform deformation realized in the material, so the formability of AZ31 alloy sheets was improved.

关键词： AZ31 magnesium alloy sheets equal-channel angular pressing mechanical properties conical cup value (CCV)

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Scavenging Effect of Perylenequinone Hydroxyls on Free Radicals: A Theoretical Study

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Chinese Chemical Letters 1998年第12期9卷 0-0+0-0页

作者： Hong Yu ZHANG (department of Biology, Provincial Key Laboratory of Animal ResistanceBiology, Shandong Teachers’ university, {2. 2.0014. Shandong Teachers Univ Dept Biol Provincial Key Lab Anim Resistance Biol Jinan 250014 Peoples R China

The sendempirical method AM1 was used to calculate AHOF values ofperylenequinone (PQ), and HOF was used as a theoretical parameter to predict the scavengingability of Po hydroxyls. Owing to strong intramolecular hydrogen bonds and the electronattracting property of the keto-function, hydroxyls of PQ were so weak in scavenging free radicalsthat the its effect was negligible in photodynandc therapy. However, when Po was substitilted withstrong electron-donating groups, its scavenging activity was enhanced markedly.

关键词： Perylenequinonoid derivatives antioxidant AM1 method △HOF value

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Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14.million years ago

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Science China Earth Sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2. LI Zhen4. TAN Hongbing2.& WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 China 2. Qinghai Institute of Salt Lakes, Chinese Academy of Sciences. Xining 810008, China 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 4. {4. of geography, Qinghai Normal {2., Xining 810008, China Chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China Chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14.million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4.00 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2. T1 were formed at 14. 11.3, 1.55, 1.2. 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14.million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14. 11.3, 1.2.and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12.million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 4.2.m during the past 1.2.million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

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Minimal regular 2.graphs and applications

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Science China Mathematics 2006年第2期49卷 158-172页

作者： FAN Hongbing, LIU Guizhen & LIU Jiping department of Physics and Computer Science, Wilfrid Laurier university, Waterloo, ON., N2. 3C5 Canada School of Mathematics and System Science, Shandong university, {4. 2.0100, China department of Mathematics and Computer Science, university of Lethbridge, Lethbridge, AB., T1K 3M4. Canada 1. department of Physics and Computer Science Wilfrid Laurier University Waterloo ON. N2L 3C5 Canada 2. School of Mathematics and System Science Shandong University Jinan 250100 China 3. department of Mathematics and Computer Science University of Lethbridge Lethbridge AB. T1K 3M4 Canada

A 2.graph is a hypergraph with edge sizes of at most two. A regular 2.graph is said to be minimal if it does not contain a proper regular factor. Let f2.n) be the maximum value of degrees over all minimal regular 2.graphs of n vertices. In this paper, we provide a structure property of minimal regular 2.graphs, and consequently, prove that f2.n) = n+3-i/3, where 1 ≤ i ≤ 6, i ≡ n (mod 6) and n ≥ 7, which solves a conjecture posed by Fan, Liu, Wu and Wong. As applications in graph theory, we are able to characterize unfactorable regular graphs and provide the best possible factor existence theorem on degree conditions. Moreover, fa(n) and the minimal 2.graphs can be used in the universal switch box designs, which originally motivated this study.

关键词： graph regular factor 2.graph switch box design.

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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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Science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2. WANG Chuan1, DENG Zhiwei3, LU Zhiheng4. & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, department of Physics, Tsinghua university, Beijing 100084.China 2. department of Materials Science and Engineering, Beijing Normal university, Beijing 100875, China 3. Testing and Analytical Center, Beijing Normal university, Beijing 100875,China 4. department of Physics, Beijing Normal university, Beijing 100875, China 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua university, Beijing 100084.China 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2.+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

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Some Hall polynomials for representation-finite selfinjective algebra with mod _pΛ without short chains

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Chinese Science Bulletin 1997年第12期42卷 985-988页

作者： ZHANG Shunhuadepartment of Mathematics, Shandong university, {2. 2.0100, China department of Mathematics Shandong University Jinan China

1 PreliminariesThe Hall algebra H（A） of a finitary ring A was defined by Ringel.H（A）is the freeAbelian group with a basis{u[M]}[M] indexed by the isomorphism classes [M] of finite A-modules M with the multiplicati... 详细信息

关键词： Hall algebras Hall polynomials short chains.

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Effects of Substrate Temperature on Properties for Transparent Conducting ZnO:A1 Films on Organic Substrate Deposited by r.f. Sputtering

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Journal of Materials Science & Technology 2001年第5期17卷 517-520页

作者： Deheng ZHANG, Dejun ZHANG and Qingpu WANG department of Physics, Shandong university, {2. 2.0100, China Tianlin YANG Institute of Zibo, Zibo 2.5091, China Dept. of Phys. Shandong Univ. Ji'nan 250100 China

This paper presents the substrate temperature dependence of opto-electrical properties for transparent conducting Al-doped ZnO films prepared on polyisocyanate (PI) substrates by r f sputtering. Polycrystalline ZnO:Al films with good adherence to the substrates having a (002. preferred orientation have been obtained with resistivities in the range from 4.1×10-3to 5.3×104.Ωcm, carrier densities more than 2.6×102. cm-3 and Hall mobilities between 5.78 and 13.11 cm2.V/s for films. The average transmittance reaches 75% in the visible spectrum. The quality of obtained films depends on substrate temperature during film fabrication.

关键词： ZnO Sputtering Effects of Substrate Temperature on Properties for Transparent Conducting ZnO Al

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Second-order consensus in networks of dynamic agents with communication time-delays

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Journal of Systems Engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1,2. Huajing Fang3, and Hua Wang4.1. School of Navigation, Wuhan university of Technology, Wuhan 4.0063, P. R. China 2. Wuhan Second Ship Design and Research Institute, Wuhan 4.0064. P. R. China 3. department of Control Science and Engineering, Huazhong university of Science and Technology, Wuhan 4.0074. P. R. China 4. department of Aerospace and Mechanical Engineering, Boston university, Boston MA02.15, USA School of Navigation Wuhan University of Technology Wuhan 430063 P. R. China Wuhan Second Ship Design and Research Institute Wuhan 430064 E R. China department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China department of Aerospace and Mechanical Engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

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