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L^(2)Extension and Effectiveness of Strong Openness Property

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Acta Mathematica Sinica,English Series 2022年第11期38卷 1949-1964页

作者： shi Jie bao Qi An GUAN School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China

In this note,we present an L^(2)extension approach to the effectiveness result of strong openness property of multiplier ideal sheaves.

关键词： Optimal L^(2)extension multiplier ideal sheaf strong openness property

Preparation and characterization of organic polymer modified composite polyaluminum chloride

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Journal of Environmental Sciences 2006年第2期18卷 214-220页

作者： shi bao-you TANG Hong-xiao State Key Laboratory of Environmental Aquatic Chemistry Chinese Academy of Sciences Beijing 100085 China

Compared with traditional aluminum salts, polyaluminum chloride （PACI） has better coagulation-flocculation performance in turbidity removal. However, it is still inferior to organic polymers in terms of bridging function. In order to improve the aggregating property of PACl, different composite PACl flocculants were prepared with various organic polymers. The effect of organic polymer on the distribution or Al（Ⅲ） species in composite flocculants was studied using ^27TAl NMR and Al-ferron complexation methods. The charge neutralization and surface adsorption characteristics of composite flocculants were also investigated. Jar tests were conducted to evaluate the turbidity removal efficacy of organic polymer modified composite flocculants. The study shows that cationic polymer and anionic polymer have significant influences on the coagulation-flocculation behaviors of PACl. Both cationic and anionic polymers can improve the turbidity removal performancc of PACl but the mechanisms arc much different： cationic organic polymer mainly increases the charge neutralization ability, but anionic polymer mainly enhances the bridging function.

关键词： polyaluminum chloride(PACl) organic polymer composite flocculant

Perceptual importance analysis for H.264/AVC bit allocation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 225-231页

作者： Gui-xu LIN shi-bao ZHENG Institute of lmage Comm. ＆ Info. Processing Dept. of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Key Laboratory of Digital Media Processing and Transmissions Shanghai Jiao Tong University Shanghai 200240 China

The existing H.264/AVC rate control schemes rarely include the perceptual *** a result,the im-provements in visual quality are hardly comparable to those in peak signal-to-noise ratio(PSNR).In this paper,we propose a perceptual importance analysis scheme to accurately abstract the spatial and temporal perceptual characteristics of video *** we perform bit allocation at macroblock(MB)level by adopting a perceptual mode decision scheme,which adaptively updates the Lagrangian multiplier for mode decision according to the perceptual importance of each *** results show that the proposed scheme can efficiently reduce bit rates without visual quality degradation.

关键词： Visual quality Human visual system Rate control H.264/AVC

Global exponential stability of Cohen-Grossberg neural networks with variable delays

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 167-174页

作者： ZHANG Li-juan shi bao Naval Aeronautical Engineering Institute Naval Aeronautical and Astronautical University Yantai264005 China School of Mathematics and Information Science Yantai University Yantai 264005 China

A class of generalized Cohen-Grossberg neural networks（CGNNs） with variable de- lays are investigated. By introducing a new type of Lyapunov functional and applying the homeomorphism theory and inequality technique, some new conditions axe derived ensuring the existence and uniqueness of the equilibrium point and its global exponential stability for CGNNs. These results obtained are independent of delays, develop the existent outcome in the earlier literature and are very easily checked in practice.

关键词： Cohen-Grossberg neural network equilibrium point delay global exponential stability

Metabolic and transcriptomic analyses elucidate a novel insight into the network for biosynthesis of carbohydrate and secondary metabolites in the stems of a medicinal orchid Dendrobium nobile

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Plant Diversity 2023年第3期45卷 326-336页

作者： Yu-Wen Zhang Yu-Cen shi shi-bao Zhang Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Yunnan Key Laboratory for Wild Plant Resources Kunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China Lijiang Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiang 674100YunnanChina

Dendrobium nobile is an important medicinal and nutraceutical *** the ingredients of *** have been identified as polysaccharides,alkaloids,amino acids,flavonoids and bibenzyls,our understanding of the metabolic pathways that regulate the synthesis of these compounds is ***,we used transcriptomic and metabolic analyses to elucidate the genes and metabolites involved in the biosynthesis of carbohydrate and several secondary metabolites in the stems of ***.A total of 1005 metabolites and 31,745 genes were detected in the stems of *** majority of these metabolites and genes were involved in the metabolism of carbohydrates(fructose,mannose,glucose,xylulose and starch),while some were involved in the metabolism of secondary metabolites(alkaloids,β-tyrosine,ferulic acid,4-hydroxybenzoate and chrysin).Our predicted regulatory network indicated that five genes(AROG,PYK,DXS,ACEE and HMGCR) might play vital roles in the transition from carbohydrate to alkaloid *** analysis identified that six genes(ALDO,PMM,BGLX,EGLC,XYLB and GLGA) were involved in carbohydrate metabolism,and two genes(ADT and CYP73A) were involved in secondary metabolite *** analyses also indicated that phosphoenol-pyruvate(PEP) was a crucial bridge that connected carbohydrate to alkaloid *** regulatory network between carbohydrate and secondary metabolite biosynthesis established will provide important insights into the regulation of metabolites and biological systems in Dendrobium species.

关键词： Dendrobium nobile Transcriptome Metabolome Polysaccharides Alkaloids Secondary metabolite biosynthesis

A Quantum Cryptography Key Distribution Way Using Orthogonal States

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Chinese Physics Letters 1997年第7期14卷 521-523页

作者： shi bao-sen GUO Guang-can Department of Physics Center of Nonlinear ScienceUniversity of Science and Technology of ChinaHefei 230026

A different quantum cryptography key distribution way based on the orthogonal states is presented in the system,instead of using two sources[***.75(1995)1239],only one source and one channel are needed to produce two ... 详细信息

关键词： phase. states quantum

Differences in leaf physiological and morphological traits between Camellia japonica and Camellia reticulata

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Plant Diversity 2020年第3期42卷 181-188页

作者： Ji-Hua Wang Yan-Fei Cai shi-Feng Li shi-bao Zhang Flower Research Institute of Yunnan Academy of Agricultural Sciences KunmingChina Key Laboratory for Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunmingChina National Engineering Research Center for Ornamental Horticulture KunmingChina

Plants of the genus Camellia are widely cultivated throughout the world as ornamentals because of their bright and large *** widely cultivated varieties are mainly derived from the mutant lines and hybrid progenies of Camellia japonica *** Camellia reticulata *** their geographical distributions and environmental adaptabilities are significantly different,no systematic comparison has been conducted between these two *** investigate differences in how these plants have adapted to their environments,we measured photosynthesis and 20 leaf functional traits of *** and *** grown under the same *** with ***,*** showed higher values for light saturation point,light-saturated photo synthetic rate,leaf dry mass per unit area and stomatal area,but lower values for apparent quantum efficiency,leaf size,stomatal density and leaf nitrogen content per unit *** area was positively correlated with light-saturated photosynthetic rate and light saturation point,but negatively correlated with stomatal *** differences between *** and *** were mainly reflected in their adaptations to light intensity and leaf morphological *** is better adapted to high light intensity than *** difference is related to the two species’ differing life fo ***,leaf morphological traits have played an important role in the light adaptation of *** and ***,and might be first noticed and selected during the breeding *** findings will contribute to the cultivation of camellia plants.

关键词： Camellia Light adaptation Leaf traits Ornamental plant Photosynthesis

Monoterpenoid Indole Alkaloids with Promoting Neurite Growth from Tabernaemontana divaricata

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Chinese Journal of Chemistry 2021年第5期39卷 1085-1092页

作者： Yan Deng Yang Yu bao-bao shi Mei-Fen bao Si-Meng Zhao Xiang-Hai Cai State Key Laboratory of Phytochemistry and Plant Resources in West Chino Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China iHumon Institute ShanghaiTech UniversityShanghai 200031China

Phytochemical investigations on Tabernaemontana divaricata led to the isolation of seven undescribed monoterpenoid indole alkaloids,taberdicatines A-G(1-7).Taberdicatines A-C might be derived from Aspidosperma-type alkaloid,less skeletal carbons in 1-2 and an additional carbon in *** D-E(4-5)were attributed to Iboga alkaloids with enantiomeric skeleton,*** 3 could promote the neurite growth of mouse primary cortical neurons at the concentration of 5 pimol/L.

关键词： Monoterpenoid indole alkaloid Taberdicatines A-G Structure elucidation Extraction and isolation Promoting neurite growth

Consensus of a two-agent opinion dynamical system with processing delay

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International Journal of Biomathematics 2018年第6期11卷 111-128页

作者： Ye Cheng Xiao Wang bao shi School of Basic Sciences for AviationNaval Aviation University Yantai 264001 P. R. China College of Science National University of Defense Technology Changsha 410073 P. R. China

A sufficient condition is obtained for a two-agent opinion dynamical system with pro-cessing delay to experience unconditional consensus. To this end, the dynamics proposed is transformed into a general class of delay differential equation and asymptotic stability of the origin is then analyzed. It is also shown that increasing delay can prolong the time needed for the system to realize consensus and even induce a Hopf bifurcation.

关键词： Opinion dynamical system consensus processing delay asymptotic stability Hopf bifurcation.