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New Isoflavonoside from Bupleurum Scorzonerifolium

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Chinese Chemical Letters 1998年第1期9卷 71-73页

作者： Li TAN Yu Ying ZHAO Bin WANG Ru Yi ZHANG (Department of Phytochemistry, Beijing Medical University, Beijing 100083)guang zhong tu(Beijing Institute of Microchemistry, Beijing 100091) Beijing Med Univ Dept Phytochem Beijing 100083 Peoples R China

A new isoflavonoside, 7-hydroxy-4'-methoxy-isoflavonone-7-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside was isolated from roots of Bupleurum scorzonerifolium Willd., and named as saikoisoflavonoside A. The st... 详细信息

关键词： Bupleurum scorzonerifolium isoflavonoside saikoisoflavonoside A

NMR StuDIES ON THE WEAK INTERACTION OF FOUR-MONONUCLEOTIDES WITH TRYPTAMIDE AND LEUCINAMIDE

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Chinese Chemical Letters 1993年第5期4卷 431-434页

作者： Wen Qing WANG Xiang DING Jian JIANG guang zhong tu Li Bin MA Shao Liang HONG Department of Technical Physics Peking UniversityBeijing 100871 Institute of Microchemistry Beijing.

NMR spectroscopy analysis was introduced to investigate the weak interaction of four 5'—mononucleotides with tryptamide and leucinamide. Assuming a 1∶1 complex formation, the association constants were determined by nonlinear regression analysis. The association affinity of 4 mononucleotides with tryptamide decreased in the order: G>A>C>U, indicating that purine bases stack more strongly with tryptamide than pyrimidine bases. But with leucinamide the affinity decreases in the order: G>C>A=U, suggesting an amino acid—anticodonic preferential interaction. The implication of the present data to the origin of genetic code was briefly discussed.

关键词： NMR StuDIES ON THE WEAK INTERACTION OF FOUR-MONONUCLEOTIDES WITH TRYPTAMIDE AND LEUCINAMIDE

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑Yuan Yu Jing Wu guang Yin Fan‑Zhen Jiao zhong‑Zhen Yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

New Octadecanoyl Diterpenoid Arabinoside from Conyza blinii

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Chemical Research in Chinese Universities 2009年第4期25卷 458-460页

作者： CHEN Lei SU Yan-fang tu guang-zhong School of Pharmaceutical Science and Technology Tianjin University Tianjin 300072 P. R China Beijing Institute of Microehemistry Beijing 100091 P. R. China

A new octadecanoyl diterpenoid glycoside,（E）-8α,15-dihydroxy-15-（3S-hydroxy-octadecanoyl）-13-labdene-8-O-α-L-arabinopyranoside（1）,was isolated from the aerial parts of Conyza blinii,and the structure was ident... 详细信息

关键词： Conyza blinii Diterpenoid Labdane Arabinoside

Analysis of gravity wave activity during stratospheric sudden warmings in the northern hemisphere

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Earth and Planetary Physics 2024年第2期8卷 415-422页

作者： XuanYun Zeng guang zhong School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410000China Key Laboratory of Geospace Environment Chinese Academy of SciencesUniversity of Science&Technology of ChinaHefei 230026China

Due to the significant changes they bring to high latitude stratospheric temperature and wind,stratospheric sudden warmings(SSWs)can have an impact on the propagation and energy distribution of gravity waves(GWs).The variation characteristics of GWs during SSWs have always been an important *** temperature data from January to March in 2014−2016,provided by the Constellation Observing System for Meteorology,Ionosphere and Climate(COSMIC)mission,we have analyzed global GW activity at 15−40 km in the Northern Hemisphere during SSW *** the SSWs that we studied,the stratospheric temperature rose in one or two longitudinal regions in the Northern Hemisphere;the areas affected extended to the east of 90°*** these SSWs,the potential energy density(E_(p)of GWs expanded and covered a larger range of longitude and altitude,exhibiting an eastward and downward *** E_(p)usually increased,while partially filtered by the eastward zonal *** zonal winds weakened or turned westward,E_(p)began to *** SSWs,the E_(p)usually *** observations can serve as a reference for analyzing the interaction mechanism between SSWs and GWs in future work.

关键词： stratospheric sudden warming gravity wave wind filter

Classification study of WISE infrared sources:identification of candidate asymptotic giant branch stars

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Research in Astronomy and Astrophysics 2013年第3期13卷 323-333页

作者： Xun tu zhong-Xiang Wang Key Laboratory for Research in Galaxies and Cosmology and Shanghai Astronomical Observatory Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

In the Wide-field Infrared Survey Explorer （WISE） all-sky source catalog there are 76 million mid-infrared point sources that were detected in the first three WISE bands and have association with only one 2MASS near-IR source within 3. We search for their identifications in the SIMBAD database and find 3.2 million identified sources. Based on these known sources, we establish three criteria for selecting candidate asymptotic giant branch （AGB） stars in the Galaxy, which are three defined zones in a color-color diagram, Galactic latitude ｜b｜〈 20°, and ＂corrected＂ WISE third-band W3c≤ 11. Applying these criteria to the WISE＋2MASS sources, 1.37 million of them are selected. We analyze the WISE third-band W3 distribution of the selected sources, and further establish that W3〈8 is required in order to exclude a large fraction of normal stars from them. We therefore find 0.47 million candidate AGB stars in our Galaxy from the WISE source catalog. Using W3c, we estimate their distances and derive their Galactic distributions. The candidates are generally distributed around the Galactic center uniformly, with 68% （1-σ） of them within approximately 8 kpc. We discuss the idea that optical spectroscopy can be used to verify the C-rich AGB stars in our candidates, and thus a fraction of them （-10%） will be good targets for the Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） survey that is planned to start in fall of 2012.

关键词： stars: AGB and post-AGB -- infrared: stars -- stars: carbon

Discordant patterns of genetic variation between mitochondrial and microsatellite markers in Acanthogobius ommaturus across the coastal areas of China

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Acta Oceanologica Sinica 2023年第4期42卷 72-80页

作者： Chenyu Song zhong tu Na Song Key Laboratory of Mariculture(Ocean University of China) Ministry of EducationQingdao 266003China Shandong Fisheries Development and Resources Conservation Center Yantai 264003China

Acanthogobius ommaturus, which belongs to the family Gobiidae, is a euryhaline and demersal fish that is widely distributed in the coastal areas, harbors, and estuaries of China, D. P. R. Korea and Japan. In this study, the genetic diversity and genetic structure of five geographical populations of A. ommaturus was assessed using the mitochondrial hypervariable region gene and microsatellite markers. The results of the two genetic markers indicated that the A. ommaturus populations had a high level of genetic diversity. The mitochondrial marker detected weak genetic differentiation among populations, and the Neighbor-Joining tree showed that there was no obvious pedigree branches and geographic structure as well. However, population of Zhoushan showed significant genetic differentiation with other populations by microsatellite markers. The population of *** has not experienced bottleneck effect recently. We speculated that the Pleistocene climate change and juvenile fish dispersal played an important role in the population differentiation of A. ommaturus.

关键词： mitochondrial markers microsatellite markers genetic diversity genetic structure Acanthogobius ommaturus

RELAXED ASYNCHRONOUS ITERATIONS FOR THE LINEAR COMPLEMENTARITY PROBLEM

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Journal of Computational Mathematics 2002年第1期20卷 97-112页

作者： zhong-zhi Bai Yu-guang Huang LSEC ICMSECAcademy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100080China Oxford University Computing Laboratory Wolfson BuildingParks RoadOxford OX1 3QDU.K.

Presents a class of relaxed asynchronous parallel multisplitting iterative methods for solving the linear complementarity problem on multiprocessor systems. Establishment of the methods; Convergence theories; Numerica... 详细信息

关键词： linear complementarity problem matrix multisplitting relaxation method asynchronous iteration convergence theory

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服务器无感知计算系统性能优化技术研究综述

软件学报 2025年第1期36卷 47-78页

作者：杨光刘杰曲慕子王帅叶丹钟华中国科学院大学中国科学院软件研究所软件工程技术研究开发中心计算机科学国家重点实验室(中国科学院软件研究所)

服务器无感知计算是新兴的云计算模式,它基于“函数即服务(FaaS)”的范式,以函数为部署和调度的基本单位,为用户提供大规模并行和自动伸缩的函数执行服务,且无需用户管理底层资源.对于用户,服务器无感知计算能够帮助他们摆脱集群底层基... 详细信息

服务器无感知计算是新兴的云计算模式,它基于“函数即服务(FaaS)”的范式,以函数为部署和调度的基本单位,为用户提供大规模并行和自动伸缩的函数执行服务,且无需用户管理底层资源.对于用户,服务器无感知计算能够帮助他们摆脱集群底层基础设施管理的负担,专注于业务层的开发和创新;对于服务提供商,服务器无感知计算将应用分解为细粒度的函数,极大地提高了调度效率和资源利用率.显著的优势让服务器无感知计算迅速吸引了业界的注意,然而,服务器无感知计算与传统云计算迥然不同的计算模式以及对任务各方面的严格限制给应用的迁移带来了诸多障碍,各种越来越复杂的任务也对服务器无感知计算的性能提出了越来越高的要求,服务器无感知计算的性能优化成为一个重要的研究课题.从4个方面对服务器无感知计算系统性能优化技术的相关研究工作进行梳理和综述,并介绍现有的系统实现.(1)介绍面向典型任务的优化技术,包括任务适配和针对特定任务的系统优化;(2)综述沙箱环境的优化工作,包括沙箱方案和冷启动优化技术,它们是决定函数运行速度的核心;(3)概括I/O和通信技术的优化,它们是服务器无感知计算应用程序的主要性能瓶颈;(4)简述相关的资源调度技术,包括面向平台和面向用户的调度策略,它们决定着系统的资源利用率和任务的执行效率.最后,总结当前服务器无感知计算性能优化技术所面临的问题和挑战,并展望未来可能的发展方向.

关键词：服务器无感知计算函数即服务云函数云计算性能优化