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Science China Chemistry 2011年第10期54卷 1565-1575页

作者： yang Ping KONG XiangZhen CHeNG ChangMei LI ChangYan yang XiaoMing ZHAO Xing'e Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology Ministry of Education Tsinghua University Beijing 100084 China Academy of Military Medical Sciences Beijing 100850 China Jiangsu Simcere Pharmaceutical Research Institute Nanjing 210042 China

Flavonoids are important bioactive dietary compounds, which are proved to be antioxidant responsive element (ARe) activators to defend against electrophilic toxicants and oxidative stress. The activators induce ARe gene transcription through Nrf2 factor, a major transcriptional stimulator of cytoprotective genes, relieved from a Keap1 complex. In this report, based on the structures of two flavonoids, scutellarin and baicalin, which are extracted from two common Chinese plants Dengzhanhua (erigeron breviscapus (vant) Hand-Mazz) and Huangqin (Scutellaria baicalensis Georigi), respectively, we synthesized several 8-substituted and deglucuronidated analogues and identified the ARe activation effects of these flavonoids. We found that the Baicalin, deglucurnonidated Baicalin and diaza cyclopenta derivative were more active. Their dose-dependent upregulation activities of ARe and NQO1 and induction effects of Nrf2 were testified. The results presented that these three analogues had good upregulation effects on ARe, and they could be potentially utilized in relieving oxidative stress, upon further neuroprotective tests.

关键词： Scutellarin Baicalin ARe activator Nrf2 NQO1

Privacy-Preserving Strategyproof Auction Mechanisms for Resource Allocation

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Tsinghua Science and Technology 2017年第2期22卷 119-134页

作者： Yu-e Sun He Huang Xiang-yang Li yang Du Miaomiao Tian Hongli Xu Mingjun Xiao School of Urban Rail Transportation Soochow University School of Computer Science and Technology Soochow University School of Computer Science and Technology University of Science and Technology of China Suzhou Institute for Advanced Study University of Science and Technology of China School of Computer Science and Technology Anhui University

In recent years, auction theory has been extensively studied and many state-of-the-art solutions have been proposed aiming at allocating scarce resources. However, most of these studies assume that the auctioneer is always trustworthy in the sealed-bid auctions, which is not always true in a more realistic scenario. Besides the privacy-preserving issue, the performance guarantee of social efficiency maximization is also crucial for auction mechanism design. In this paper, we study the auction mechanisms that consider the above two aspects. We discuss two multi-unit auction models： the identical multiple-items auction and the distinct multiple-items *** the problem of determining a multi-unit auction mechanism that can maximize its social efficiency is NPhard, we design a series of nearly optimal multi-unit auction mechanisms for the proposed models. We prove that the proposed auction mechanisms are strategyproof. Moreover, we also prove that the privacy of bid value from each bidder can be preserved in the auction mechanisms. To the best of our knowledge, this is the first work on the strategyproof multi-unit auction mechanisms that simultaneously consider privacy preservation and social efficiency maximization. The extensive simulations show that the proposed mechanisms have low computation and communication overheads.

关键词： approximation mechanism multi-unit auction privacy preserving social efficiency strategyproof

Orientation gradient on surface of non-oriented electrical steel annealed by γ → α transformation

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Journal of Iron and Steel Research International 2020年第1期27卷 88-95页

作者： Jin-hua Wang Ping yang Wei-min Mao Feng-e Cui School of Materials Science and engineering University of Science and Technology BeijingBeijing 100083China

The microstructures and textures of the non-oriented electrical steel sheets under various annealing conditions were *** orientation gradient in the interior of grains appeared on the surface of steel sheets after α→γ→α transformation in various *** orientation gradient that appeared on the surface was inherited into the center of the steel sheet in H2 atmosphere,while that appeared only in the grains of the surface layer during γ→α transformation with N2 *** thin oxide scale was generated in various atmospheres containing traces of O2 and *** formation mechanism of orientation gradient is related to the thermal stress caused by the difference of thermal expansion coefficients between the oxide scale and the thin ferrite on the *** combined effect of phase transformation stress and thermal stress caused the plastic deformation of the thin ferrite grains on the surface in the initial stage of γ→α transformation,and then the orientations of the thin ferrite grains gradually rotated and caused the orientation gradient in the interior of grains.

关键词： electrical steel Texture Phase transformation-Thermal stress Oxide scale

Synthesis of M_xH_yTi_3O_7 nanotubes by simple ion-exchanged process and their adsorption property

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Chinese Science Bulletin 2007年第18期52卷 2491-2495页

作者： SONG XuChun yang e ZHeNG YiFan Department of Chemistry Fujian Normal University Fuzhou 350007 China College of Chemical engineening & Materials Science Zhejiang University of Technology Hangzhou 310004 China

The MxHyTi3O7 (M=K, Fe, Zn, Co, Na, Ag) nanotubes were prepared by ion-exchange reactions, in which H2Ti3O7 nanotube reacted with salts of K2SO4, Na2SO4, Fe(NO3)3, ZnSO4, Co(NO3)2 and AgNO3 in solution respectively. The properties of products were characterized by SeM, TeM, XRD and eDX. Synthesis of MxHyTi3O7 nanotubes by ion-exchanged process was proved by our experimental results. The adsorp- tion properties of MxHyTi3O7 nanotube for methylene blue in aqueous solution were studied.

关键词：纳米材料钛酸盐纳米管离子交换过程吸收特征

Cold stratification,temperature,light,GA3,and KNO3 effects on seed germination of Primula beesiana from Yunnan,China

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Plant Diversity 2020年第3期42卷 168-173页

作者： Li-e yang De-Li Peng Zhi-Min Li Li Huang Juan yang Hang Sun School of Tourism and Geography Yunnan Normal UniversityKunming650500YunnanChina School of Life Science Yunnan Normal UniversityKunming650500YunnanChina Key Laboratory for Plant Diversity and Biogeography of east Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina National Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina

Primula beesiana *** an attractive wildflower endemically distributed in the wet habitats of subalpine/alpine regions of southwestern *** study is an attempt to understand how this plant adapts to wet habitats and high ***,we examined the effects of cold stratification,light,GA3,KNO3,and temperature on *** seed ***3 and GA3 increased germination percentage and germination rate compared to control treatments at 15/5 and 25/15℃.Untreated seeds germinated well(>80%)at higher temperatures(20,25 and 28℃),whereas at lower(5,10 and15℃)and extremely high temperatures(30 and 32℃)germination decreased ***,after cold stratification(4-16 weeks),the germination percentage of *** seeds at low temperatures(5-15℃)and the germination rate at high temperatures(30℃)increased significantly,suggesting that *** has type 3 non-deep physiological *** base temperature and thermal time for germination decreased in seeds that were cold stratified for 16 ***-stratified seeds incubated at fluctuating temperatures(especially at 15/5℃)had significantly high germination percentages and germination rates in light,but not in dark,compared to the corresponding constant temperature(10℃).Seeds had a strict light requirement at all temperatures,even after experiencing cold stratification;however,the combinations of cold stratification and fluctuating temperature increased germination when seeds were transferred from dark to *** dormancy/germination responses to light and temperature are likely mechanisms that ensure germination occurs only in spring and at/near the soil surface,thus avoiding seedling death by freezing,inundation and/or germination deep in the soil.

关键词： Alpine plant Fluctuating temperature Germination ecology Light requirement Seed dormancy

Tensile Strength Characteristics of GFRP Bars in Concrete Beams with Work Cracks under Sustained Loading and Severe environments

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Journal of Wuhan University of Technology(Materials Science) 2013年第5期28卷 934-937页

作者：何雄君 yang Jingnan Charles e Bakis School of Transportation Wuhan University of Technology Department of engineering Science and Mechanics Pennsylvania State UniversityUniversity Park

To investigate the effect of different environmental conditions of GFRP bars in concrete beams with work cracks subjected to sustained loads, the beams were exposed in indoor, freeze/thaw cycles and immersed in alkaline solution at elevated temperature. The bars were carefully extracted from the beams and tested in order to evaluate residual tensile properties. The results show that the tensile strength decreased significantly in the highly aggressive conditions but not in the natural conditions. The effect of GFRP bars casting in concrete beams demonstrated approximately 2.5% decrease of tensile strength caused by pore water environment in concrete beams on basis of those of the original bars. The effect of sustained loading plus work cracks demonstrated about 10.5% tensile strength decrease on basis of those of the bars only casted in concrete beams. The effect of environments under sustained loading plus work cracks demonstrated about 17% tensile strength decrease caused by a saturated solution of Ca（OH）2 and 60-2 ℃ tap water （pH=12-13） and about 8% tensile strength decrease caused by freezing and thawing cycle （F/T）, both on basis of those of the bars of the indoor beams only under sustained loading plus work cracks. The results demonstrate the effects of the tensile strengths under different environmental conditions of GFRP bars in concrete beams with work cracks subjected to sustained loads.

关键词： GFRP bars concrete beams working cracks sustained loading and severe environments tensile strength

Compositional Variation and Mineral Chemistry of the Jinshajiang and Lancangjiang Serpentinites, Yunnan Province, SW China

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Acta Geologica Sinica(english edition) 2014年第6期88卷 1705-1728页

作者： Ahmed e.I.MASOUD yang Jingsui LIU Fei State Key Laboratory of Continental Tectonics and Dynamics Institute of Geology Chinese Academy of Geological Sciences Faculty of earth Sciences China University of Geosciences Geology Department Faculty of Science Tanta University

We present the whole rock and the mineral chemical data for upper mantle peridotites from the San-Jiang region in Yunnan, SW China. These peridotites are a part of a Paleo-Tethyan ophiolite belt occurring along the Jinshajiang and Lancangjiang suture zones. All samples of the Jinshajiang and Lancangjiang ultramafic rocks are completely serpentinized. The Jinshajiang serpentinites are characterized by no relict of olivine and pyroxene, and the Cr# content of spinels is 0.32–0.49. The Lancangjiang serpentinites were collected from two different locations; the northern location which has some relict of Opx（Al2O3 is 0.13–2.2 wt%, TiO 2 is 0.004–0.057 wt% and Mg# content is 0.895–0.933） and the Cr# content of spinel is 0.26-0.55; the southern location, which has some relict of Olivine（Fo = 90–92.5 and NiO = 0.12–0.26 wt%）, and spinel Cr# ranging from 0.41 to 0.57. The whole rock geochemical and the mineral chemistry data imply that the Jinshajiang and Lancangjiang serpentinites represent abyssal peridotites residues after ~15–20% partial melting for the Jinshajiang and Lancangjiang serpentinites（south location）, and ~11–19% partial melting for the Lancangjiang serpentinites（north location）. In addition, the compositional trends of the spinel analyses of the Lancangjiang serpentinites imply that the MORB melt-peridotite interaction process played a significant role during their evolution. These processes are evidenced by an increase in Cr# with an increase in TiO 2, whereas the spinel analyses of the Jinshajiang serpentinites display an increase in Cr# with a decrease in Ti O2, indicating that the Jinshajiang serpentinites were subjected to a simple partial melting process.

关键词： chromite Jinshajiang ophiolite Lancangjiang ophiolite

South Asian High and Asian-Pacific-American Climate Teleconnection

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Advances in Atmospheric Sciences 2005年第6期22卷 915-923页

作者：张培群 Song yang Vernon e. KOUSKY National Climate Center China Meteorological Administration Beijing 100029 NOAA＇s Climate Prediction Center Camp Springs Maryland

Growing evidence indicates that the Asian monsoon plays an important role in affecting the weather and climate outside of Asia. However, this active role of the monsoon has not been demonstrated as thoroughly as has the variability of the monsoon caused by various impacting factors such as sea surface temperature and land surface. This study investigates the relationship between the Asian monsoon and the climate anomalies in the Asian-Pacific-American （APA） sector. A hypothesis is tested that the variability of the upper-tropospheric South Asian high （SAH）, which is closely associated with the overall heating of the large-scale Asian monsoon, is linked to changes in the subtropical western Pacific high （SWPH）, the midPacific trough, and the Mexican high. The changes in these circulation systems cause variability in surface temperature and precipitation in the APA region. A stronger SAH is accompanied by a stronger and more extensive SWPH. The enlargement of the SWPH weakens the mid-Pacific trough. As a result, the southern portion of the Mexican high becomes stronger. These changes are associated with changes in atmospheric teleconnections, precipitation, and surface temperature throughout the APA region. When the SAH is stronger, precipitation increases in southern Asia, decreases over the Pacific Ocean, and increases over the Central America. Precipitation also increases over Australia and central Africa and decreases in the Mediterranean region. While the signals in surface temperature are weak over the tropical land portion, they are apparent in the mid latitudes and over the eastern Pacific Ocean.

关键词： South Asian high subtropical western Pacific high mid-Pacific trough Mexican high Asian-Pacific-American climate

GROWTH MORPHOLOGIeS OF A BINARY ALLOY WITH LOW ANISOTROPY IN DIReCTIONAL SOLIDIFICATION

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Acta Metallurgica Sinica(english Letters) 2007年第4期20卷 258-264页

作者： M.e Li G. C. yang School of Materials Science and engineering Xi＇an Jiaotong UniversityXi＇an 710049 China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

Two new classes of growth morphologies, called doublons and seaweed, were simulated using a phase-field method. The evolution of doublon and seaweed morphologies was obtained in directional solidification. The influence of orientation and velocity on the growth morphology was investigated. It was indicated that doublons preferred growing with its crystallographic axis aligned with the heat flow direction. Seaweed, on the other hand, could be obtained by tilting the crystalline axis to 45°. Stable doublons could only exist in a range of velocity regime. Beyond this regime the patterns formed would be unstable. The simulation results agreed with the reported experimental results qualitatively.

关键词： growth morphologies low anisotropy phase-field method directional solidification

Jigsaw-Sketch: a fast and accurate algorithm for finding top-k elephant flows in high-speed networks

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Science China(Information Sciences) 2024年第4期67卷 113-130页

作者： Boyu ZHANG He HUANG Yu-e SUN yang DU Dan WANG School of Computer Science and Technology Soochow University School of Rail Transportation Soochow University

Finding top-k elephant flows in high-speed networks is one of the most fundamental network measurement tasks. It is more challenging than per-flow size estimation since the IDs and sizes of top-k flows must be tracked simultaneously. Most existing studies only record the IDs of a small number of elephant flows to fit their estimators in the extremely limited high-speed on-chip memory. However, these solutions need too many memory accesses when a packet arrives to track the elephant flows with high accuracy, which limits their practicability. Therefore, this paper proposes Jigsaw-Sketch, a new algorithm to find the top-k elephant flows with much fewer memory accesses while achieving high memory efficiency and accuracy. In this design, we propose a novel two-stage jigsaw storage scheme, which can capture the candidate top-k flows from massive network steams efficiently, and further find the top-k elephant flows with high memory efficiency and only a few memory accesses for each packet. extensive experimental results based on real network traces show that Jigsaw-Sketch improves the packet processing throughput by at least 86%, while achieving smaller memory footprints and higher accuracy compared to the SOTA.

关键词： sketch top-k network measurement elephant flow high-speed networks