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Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3, WANG Pengxin4. YANG Hua1,2,3, LIU Shaomin1,2,3 & WANG Jindi1,2,3 1. Research Center for Remote Sensing and GIS, School of Geography, beijing Normal university, beijing 100875, china 2. State Key Laboratory of Remote Sensing Science, beijing 100875, china 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, china 4. department of Information management, college of Information and electronic {13.,{14., beijing 100083. china 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. department of Information management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Tissue-specific expression of glutathione S-transferases induced by 2-tridecanone or quercetin in cotton bollworms, Helicoverpa armigera (Hübner)

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Progress in Natural Science:Materials International 2005年第11期15卷 988-992页

作者： TANG Fang, LIANG Pei and GAO Xiwu (department of Entomology, china agricultural university, beijing 100094. china) department of Entomology China Agricultural University Beijing 100094 China

The tissue-specific expression of glutathione S-transferases (GSTs) in the cotton bollworm and the expression level induced by 2-tridecanone and quercetin were examined using the methods of biochemistry and the quantitative PCR. The relative expression level of GST mRNA was unanimous with the GSTs activity conjugaging with 1-chloro-2, 4.dimitro-benzene (CDNB) in fat bodies, midguts, heads and integuments of cotton bollworms. The GSTs activity in fat bodies was the highest, then midguts, heads and integuments in turn, which was in consistent with the relative expression level of GST mRNA. The specific activity of GSTs and the relative expression level of GST mRNA could be significantly induced by 2-tridecanone and quercetin, and after the induction the order of the GSTs activity and the relative expression level of GST mRNA in the above four tissues in cotton bollworms was not different from the control. The induction of GSTs by 2-tridecanone was stronger than by quercetin in all four tissues, which was in accordance with the relative expression level of GST mRNA. It suggested that the increase of GSTs activity induced by plant allelochemicals was associated with the elevated expression of GST mRNA in cotton bollworms.

关键词： Helicoverpa armigera glutathione S-transferase tissue-specific expression plant allelochemicals.

Carbon isotope ratios of C_(4. plants in loess areas of North china

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Science china Earth Sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2,3, HAN Jiamao 2, ZHOU Liping3, XIONG Xiaogang4. TAN Ming2, WU Zhenhai5 & PENG Jun6 1. department of Plant Nutrition, china agricultural university, beijing 100094. china 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 3. college of Environmental Sciences, MOE Laboratory for Earth Surface Processes, Peking university, beijing 100871, china 4. Institute of Botany, Chinese Academy of Sciences, beijing 100093, china 5. Northwest Sci-Tech university of Agriculture and Forestry, Yangling 712100, china 6. Network Center, china agricultural university, beijing 100094. china 1. department of Plant Nutrition China Agricultural University Beijing 100094 China 2. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. college of Environmental Sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. Institute of Botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech university of Agriculture and Forestry Yangling 712100 China 6. Network Center China Agricultural University Beijing 100094 China

Carbon isotope ratios (δ^(13.C) of 89 C_4.plant samples were determined fromthe loess area in North china. δ^(13.C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13.C values of C_4.plants show a slight decreasingtrend. The δ^(13.C values of C_4.plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3 species.

关键词： C4 plants, carbon isotope ratios, loess area.

Construction and characterization of the transformation-competent artificial chromosome (TAC) libraries of Leymus multicaulis

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Science china(Life Sciences) 2008年第7期51卷 604-613页

作者： XU YueYu 1,2,3,ZHOU YuLei 4.5 ,SONG LinLin 6 ,ZHANG Yan 3 &ZHAO MaoLin 1 1 beijing Agro-Biotechnology Research Center,beijing Academy of Agriculture and Forestry Science,beijing 100097,china 2 {4. of Chemistry and Chemical engineering,Hunan Institute of engineering,Xiangtan 4.1104.china 3 college of Life Science,Capital Normal university,beijing 100037,china 4.college of Life Science,Zhongkai university of Agriculture and Technology,Guangzhou 510225,china 5 college of Grassland Science,Gansu agricultural university,Lanzhou 730070,china 6 {4. of Biology,Henan Institute of Science and Technology,Xinxiang 4.3003,china 1. beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Science Beijing 100097 China 2. department of Chemistry and Chemical engineering Hunan Institute of Engineering Xiangtan 411104 China 3. college of Life Science Capital Normal University Beijing 100037 China 4. college of Life Science Zhongkai University of Agriculture and Technology Guangzhou 510225 China 5. college of Grassland Science Gansu Agricultural University Lanzhou 730070 China 6. department of Biology Henan Institute of Science and Technology Xinxiang 453003 China

Transformation-competent artificial chromosome system is able to clone and transfer genes efficiently in *** order to clone genes highly tolerant to barley yellow dwarf virus(BYDV),Aphids,drought and salt from Leymus multicaulis,the two TAC genomic libraries I and II were constructed in vector pYLTAC17 and pYLTAC74.H/sacB,which contain about 165000 and 236000 recombinant clones *** genome coverage of the two libraries was totally estimated to be about 3―5 haploid genome equivalents,as size selection of genomic DNA fragments was approximately from 9 to 300 *** of the genomic libraries were collected as bulked pools each containing 500 clones or so,stored in twelve 96-deep-well plates and then were gridding in triplicate onto a high-density colony hybridization filter with a 3×3 pattern using a GeneTAC?G3 arraying robot after being transferred manually into three 384.well *** 2501 and 2890 clones of Library in pYLTAC17 and in pYLTAC74.H/sacB were stored individually in fourteen 384.well plates and then were automatically gridding in duplicate onto a high-density colony hybridization filter with a 6×6 pattern after a replication of *** positive clones were detected by using the probe glutahione reductase gene of *** libraries constructed here can be used to isolate genomic clones containing target genes,and to carry out genome walking for positional *** the target TAC clones were isolated,they could be immediately transferred into plant genomes with the Agrobacterium system.

关键词： Leymus multicaulis megabase-size DNA transformation-competent artificial chromosome(TAC) genomic library

COMPLEXITY ANALYSIS OF NETWORK-BASED DYNAMICAL SYSTEMS

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Journal of Systems Science & Complexity 2011年第3期24卷 413-432页

作者： Guofeng ZHANG Long WANG Tongwen CHEN School of electronic engineering University of Electronic Science and Technology of China Chengdu 610054 China. Intelligent Control Laboratory Center for Systems and Control College of Engineering Peking University Beijing 100871 China department of Electrical and Computer engineering University of Alberta Edmonton Alberta T6G 2V4 Canada

This paper investigates the nonlinear dynamics of network-based dynamical systems where network communication channels of finite data rates are inserted into the closed loops of the control systems. The authors analyze the bifurcation and chaotic behavior of the non-smooth dynamical systems. The authors first prove that for almost all system parameters there are no periodic orbits. This result distinguishes this type of non-smooth dynamical systems from many others exhibiting border-collision bifurcations. Next, the authors show analytically that the chaotic sets are separated from the region containing the line segment of all fixed points with a finite distance. Finally, the authors employ a simple model to highlight that both the number of clients sharing a common network channel and fluctuations in the available network bandwidth have significant influence on the performance of such dynamical systems.

关键词： Bifurcation feedback network-based dynamical system non-convexity periodicity.

High-speed reconstruction for ultra-low resolution faces

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Science china(Information Sciences) 2012年第9期55卷 2102-2108页

作者： WANG Li ,CHEN JianSheng,HE JinPing & SU GuangDa department of electronic engineering,Tsinghua university,{4. 100084.china 1. department of electronic engineering Tsinghua University Beijing 100084 China

In this paper,a learning-based high-speed reconstruction system for ultra-low resolution faces is implemented using a software/hardware co-design *** hardware component working at 60 MHz contains a field programmable gate array,which is reconfigured to contain parallel processing units,and multiple memories to create parallel *** hardware component effectively handles generating and sorting computationally intensive similarity *** solves the processing speed problem in learning-based super-resolution reconstruction for ultra-low resolution *** system can reconstruct faces using 8 × 6,16 × 12,and 32 × 24.sized images,with 4.× 4.8 × 8,or 16 × 16 times *** experimental results verify the effectiveness of our system in terms of both visual effect and low root mean square *** processing speed can be improved up to a maximum of 7900 times faster than a pure software implementation using C.

关键词： neighborhood image parallel computer template matching pixel compensation pipeline

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china Earth Sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4. LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Re-search, Chinese Academy of Sciences, beijing 100101, china 2. Institute of Forestry, Chinese Academy of Forestry Sciences, beijing 100091, china 3. {4. of Civil engineering, university of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center, Chinese Academy of Sciences, beijing 100085, china 5. college of Resources and Environment, Southwest agricultural university, Chongqing 4.0716, china Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. department of Civil engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. college of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4. less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Enhancement of magnetism of Zn0.95Co0.05O films by p-type Cu+ doping

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Progress in Natural Science:Materials International 2011年第1期21卷 31-35页

作者： Wei-chang HAO~(1,5),Jian-jun LI~2,Huai-zhe XU~3,Jia-ou WANG~4.Tian-min WANG~1 1.Center of Materials Physics and Chemistry,Beihang university,beijing 100083.china 2.{4. of Materials Science and engineering, Anhui university of Science and Technology,Huainan 232001,china 3.{4. of Physics,Beihang university,beijing 100083.china 4.beijing Synchrotron Radiation Facility,Institute of High Energy Physics, Chinese Academy of Sciences,10004.,china 5.Key Laboratory of Micro-nano Measurement,Manipulation and Physics, Ministry of Education,Beihang university,beijing 100191,china [a] Center of Materials Physics and Chemistry Beihang University Beijing 100083 China [b] department of Materials Science and engineering Anhui University of Science and Technology Huainan 232001 China [c] department of Physics Beihang University Beijing 100083 China [d] beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences 100049 China [e] Key Laboratory of Micro-nano Measurement Manipulation and Physics Ministry of Education Beihang University Beijing 100191 China

Zn0.95Co0.05O and Zn0.91Co0.05Cu0.04. thin films were fabricated on Si（111） substrate by the reactive magnetron sputtering method at different O-Ar *** characterizations by X-ray diffractometry（XRD）,X-ray photo-electronic spectrum（XPS）, and electron paramagnetic resonance（EPR） indicate that the doped Cu ions substitute the Zn2+ions in the ZnO *** doped Cu ions are in Cu+and Cu2+mixture valence *** ferromagnetism of the Zn0.91Co0.05Cu0.04. film increases gradually the increasing Cu+ions *** results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ions themselves,but owing to the enhancement of magnetic interaction between Co ions,which suggests that p-type doping of Cu+ions plays an important role in mediating the ferromagnetic coupling between Co ions.

关键词： Zn0.95Co0.05O films Zn0.91Co0.05Cu0.04. films magnetic semiconductors magnetic coupling co-doping

electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3,ZHANG FuChun3,ZHANG ZhiYong4.LU ShuYuan5 & YANG YanNing3 1 Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710068,china 2 Graduate university of Chinese Academy of Sciences,beijing 10004.,china 3 {4. of Physics and electronic Information,Yan’an university,Yan’an 716000,china 4.Information Science and Technology Institution,Northwest university,Xi’an 710127,china 5 department of Telecommunications,Xi’an Institute of Posts and Telecommunications,Xi’an 710121,china 1. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710068 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. College of Physics and Electronic Information Yan’an University Yan’an 716000 China4. Information Science and Technology Institution Northwest University Xi’an 710127 China5. Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an 710121 China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3p electron spins and Fe 3d electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3d electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties