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Contrasting responses of legume versus non-legume shrubs to soil water and nutrient shortages in the Mu Us Sandland

Journal of Plant Ecology 2011年第4期4卷 268-274页

作者： Yuan sui Qingguo Cui ming Dong Weiming He State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesNo.20 NanxincunXiangshanHaidian DistrictBeijing 100093China Graduate University of Chinese Academy of Sciences 19A YuquanluBeijing 100049China

Legumes and non-legumes usually differ in using soil water and *** water and nutrients are scarce in the semi-arid Mu Us Sandland where legume and/or non-legume shrubs coexist/***,we addressed the responses of legume versus nonlegume shrubs to different soil water and nutrient *** We conducted an experiment in which a legume(Hedysarum laeve)and a non-legume(Artemisia ordosica)were used,both of which are dominant species in the Mu Us *** of these two species were subjected to three water levels(45.0,67.5 and 90.0 ml every 3 days)and three nutrient treatments(0,0.1%and 0.2%nutrient solution every week)during the *** Findings Interactions between water and nutrients on total biomass,root weight ratio and rain use efficiency(RUE)were detected in *** but not in ***,suggesting that water effects on *** but not on *** are dependent on soil *** addition alleviated drought stress and increased RUE in *** interspecific differences in response to soil water and nutrients may be linked to the ability of plants to fix *** addition,under lowsoil water or nutrient conditions,*** produced more biomass than ***,and the opposite was the case under high-soil *** relationship between relative growth rate(RGR)and RUE[or nutrient use efficiency(NUE)]varied with two *** of *** was positively correlated with both RUE and NUE while RGR of *** was negatively correlated with *** different responses may be linked to the trade-off between high-growth rate and low-resource use efficiency.

关键词： biomass legume versus non-legume rain use efficiency resource use strategies root weight ratio

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Inequalities on the Inner Radius of Univalency and the Norm of Pre-Schwarzian Derivative

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Acta Mathematica Sinica,English Series 2009年第1期25卷 59-64页

作者： Tao CHENG Yue ming KANG Ji xiu CHEN Academy of Mathematics and Systems Science CAS Beijing 100190 P. R. China Department of Mathematics Jiangxi Normal University Nanchang 330027 P. R. China Business Information Management School Shanghai Institute of Foreign Trade Shanghai 201600 P. R. China School of Mathematical Sciences Fudan University Shanghai 200433 P. R. China

In this paper, we get a lower bound of inner radius of univalency of Schwarzian derivative by means of the norm of pre-Schwarzian derivative. Furthermore, we apply the theory of Universal Teichmuller Space to explain its geometric meaning which shows the relationship between the inner radius in Universal Teichmuller Space embedded by Schwarzian derivative and the norm defined in Universal Teichmuller Space embedded by pre-Schwarzian derivative.

关键词： Pre-Schwarzian derivative inner radius of univalency Universal Teichmuller Space

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One-pot Synthesis of Dimethyl Carbonate in the Presence of a Two-component Catalyst

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Chemical Research in Chinese Universities 2005年第6期21卷 714-717页

作者： CHEN xiu-zhi HU Chang-wen GAO Zhi-ming The Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 P. R. China Department of Chemistry Beijing Institute of Technology Beijing 100081 P. R. China

The one-pot synthesis of dimethyl carbonate（DMC） with co-production of propy-lene carbonate（PC） and propylene glycol（PG） from propylene oxide（ PO）, carbon dioxide and methanol as the starting materials was investigated. The catalyst adopted here was a mixture of tetrabutyl ammonium bromide and sodium methoxide. It was found that un- der the reaction conditions of t = 150 ℃, p =3-4 MPa and 2 h, the PO conversion could reach 100%, the DMC, PC and the PG selectivities were 49. 7%, 42. 7% and 49. 8%, respectively, and the selectivity of by-products was below 10%.

关键词： Dimethyl carbonate Carbon dioxide Propylene oxide Propylene carbonate Catalyst

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Microstructure, mechanical and biodegradable properties of a Mg–2Zn–1Gd–0.5Zr alloy with different solution treatments

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Rare Metals 2019年第6期38卷 532-542页

作者： Jun-xiu Chen ming Gao Li-Li Tan Ke Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Solution treatment is a useful way to improve the degradation resistance of Mg *** this work,effects of solution treatment temperature on mechanical and biodegradable properties of an extruded Mg–2Zn–1Gd–0.5Zr alloy were *** analysis,tensile test, three-point bending test, immersion test and electrochemical test were *** results showed that increasing solution temperature decreases the mechanical properties of the ***, three-point bending test revealed that the solution-treated alloy at 510 ℃ could maintain 95% of its maximum bending force(Fmax) during the 28-day immersion *** treatment at 510 ℃ for 5 h, all the second phases were dissolved into the alloy, the galvanic corrosion was inhibited, and the alloy exhibited good corrosion resistance with a corrosion rate of 0.35 mm·year-1 in Hank’s solution.

关键词： Mg alloy Solution treatment Microstructure Mechanical property Biodegradable property

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3D Modeling of the preparation process of metal rubber material

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 75-79页

作者： ming-ji Huang xiu-ping Dong Guo-quan Liu School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China School of Mechanical Engineering Beijing Technology and Business University Beijing 100048 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Based on the analysis of the preparation of metal rubber （MR） and two pivotal hypotheses, the uniform distribution and the unaltered topological structure of wires in the radial direction of columns in the punch process, a 3D parametrical model was established based on four approaches： helix-making, planar roughcast-weaving, planar roughcast-rolling, and 3D roughcast punching. In the modeling process, 5 lattice types of weave patterns in planar roughcast were put forward, and 10 quantificational modeling parameters were picked up to exclusively define the column MR component structure. The wire distribution was visualized by CAD techniques. The important performance parameter of column MR components （relative density ρ^- ） can be forecasted by modeling computing, which provides the necessary foundation for the design and optimization of MR materials.

关键词： metal rubber preparation process weaving parametric model

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Response analyses on the drill-string channel for logging while drilling telemetry

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Petroleum Science 2023年第5期20卷 2796-2808页

作者： Ao-Song Zhao Xiao He Hao Chen xiu-ming Wang State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Beijing Engineering Research Center of Sea Deep Drilling and Exploration Institute of AcousticsChinese Academy of SciencesBeijing100190China

Downhole acoustic telemetry(DAT),using a long drill string with periodical structures as the channel,is a prospective technology for improving the transmission rate of logging while drilling(LWD)*** studies only focused on the acoustic property of a free drill string and neglected the coupling between pipes and fluid-filled *** addition to the drill-string waves,a series of fluid waves are recorded in the DAT channel,which has not been investigated *** channel characteristics result in lower transmission rates and stability than ***,a more realistic channel model is needed considering the fluid-filled *** this paper,we propose a hybrid modeling method to investigate the response characteristics of the DAT *** combining the axial wavenumbers and excitation functions of mode waves in radially layered LWD structures,the channel model is approximated to the 1-D propagation,which considers transmission,reflection,and interconversion of the drillstring and fluid *** proposed 1-D approximation has been well validated by comparing the 2-D finite-difference *** is revealed that the transmitted and converted fluid waves interfere with the drill-string wave,which characterizes the DAT channel as a particular coherent multi-path *** a fluid-filled borehole surrounds the drill string,the channel responses exhibit considerable delay as well as strong frequency selectivity in amplitude and *** new findings suggest that the complexity of the channel response has been underestimated in the past,and therefore channel measurements on the ground are *** address these channel characteristics,we apply a noncoherent demodulation *** transmission rate for synthetic data reaches 15 bps in a 94.5 m long channel,indicating that the acoustic telemetry is promising to break the low-speed limitation of mud-pulse telemetry.

关键词： Logging while drilling Borehole geophysics Downhole acoustic telemetry Channel modeling Frequency selectivity

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Facile synthesis of size-tunable stable nanoparticles via click reaction for cancer drug delivery

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Science China Chemistry 2014年第4期57卷 633-644页

作者： CAO ming LIU XiangRui TANG JianBin sui MeiHua SHEN YouQing Key Laboratory of Biomass Chemical Engineering of Ministry of Education Center for Bionanoengineering of Zhejiang University Department of Chemical and Biological Engineering Zhejiang University

The stability and size of polymeric nanoparticles are two of the most important parameters determining their pharmacokinetics and tumor/drug accumulation efficiency in cancer-drug delivery. Herein, we report a facile one-pot synthesis of crosslinked nanoparticles(CNPs) with tunable sizes and polyethylene glycol(PEG) shells via click reactions. Simply by adjusting the contents of the macromonomer(PEG monoacrylate) in its reaction with ethylene diacrylate and a crosslinker containing hexa-thiols groups, the sizes of the resulting PEGylated crosslinked nanoparticles could be easily tuned from 10 to 90 nm. These nanoparticle cores could encapsulate hydrophobic drugs such as doxorubicin(DOX), and the unreacted thiol and acrylate groups could be used for drug conjugation or labeling. Thus, the nanoparticles provide a multifunctional platform for drug delivery. In vivo studies showed that the larger nanoparticles(about 83.7 nm) had a much longer blood-circulation time and better tumor-targeting efficiency. One of our most important findings was that the drug encapsulated in the crosslinked nanoparticles, even though little was released at pH 7.4 under in vitro conditions, had much faster blood clearance than the nanoparticles' carrier, suggesting that drug release in the bloodstream was significant.

关键词： crosslinked nanoparticles facile synthesis size effect pharmacokinetics tumor targeting

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Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

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Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： ming-Hong Luo Qing-Wen Tang xiu-Rong Mo Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray *** this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven *** γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

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Interleukin-34 promotes the proliferation and epithelial-mesenchymal transition of gastric cancer cells

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World Journal of Gastrointestinal Oncology 2022年第10期14卷 1968-1980页

作者： Chuan-Hong Li Zhang-ming Chen Pei-Feng Chen Lei Meng Wan-Nian sui Song-Cheng Ying A-Man Xu Wen-xiu Han Department of General Surgery The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Immunology College of Basic MedicineAnhui Medical UniversityHefei 230022Anhui ProvinceChina

BACKGROUND Interleukin(IL)-34 is a pro-inflammatory cytokine involved in tumor *** role of IL-34 in the proliferation and epithelial-mesenchymal transition(EMT)of gastric cancer(GC)remains to be *** To investigate whether and how IL-34 affects the proliferation of GC cells and *** Using immunohistochemical staining,the expression of IL-34 protein was detected in 60 paired GC and normal paracancerous tissues and the relationship between IL-34 and clinicopathological factors was *** expression of IL-34 mRNA and protein in normal gastric epithelial cell lines and GC was detected using quantitative real-time polymerase chain reaction(qRT-PCR)and western blotting,*** IL-34 knockdown and overexpression in AGS cell lines were established by lentiviral infection and validated by qRT-PCR and western *** cholecystokinin-8 assay,clone formation assay,cell scratch assay,and transwell system were used to detect GC cell proliferation,clone formation,migration,and invasion capacity,*** effects of IL-34 on the growth of GC transplant tumors were assessed using a subcutaneous transplant tumor assay in nude *** effects of IL-34 on the expression level of EMT-associated proteins in AGS cells were examined by western *** Expression of IL-34 protein and mRNA was higher in GC cell lines than in GES-1 *** to matched normal paraneoplastic tissues,the expression of IL-34 protein was higher in 60 GC tissues,which was correlated with tumor size,T-stage,N-stage,tumor,node and metastasis stage,and degree of *** of IL-34 expression inhibited the proliferation,clone formation,migration,and invasion of AGS cells,while overexpression of IL-34 promoted cell proliferation,clone formation,migration,and ***,the reduction of IL-34 promoted the expression of E-cadherin in AGS cells but inhibited the expression of vimentin and *** of IL-3

关键词： Gastric cancer Interleukin-34 Proliferation Epithelial-mesenchymal transition Metastasis

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NfvInsight:A Framework for Automatically Deploying and Benchmarking VNF Chains

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Journal of Computer Science & Technology 2022年第3期37卷 680-698页

作者： Tian-Ni Xu Hai-Feng Sun Di Zhang Xiao-ming Zhou xiu-Feng sui Sa Wang Qun Huang Yun-Gang Bao State Key Laboratory of Computer Architecture Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China Peng Cheng Laboratory Shenzhen 518055China Department of Computer Science and Technology Peking UniversityBeijing 100871China

With the advent of virtualization techniques and software-defined networking(SDN),network function virtualization(NFV)shifts network functions(NFs)from hardware implementations to software appliances,between which exists a performance *** to narrow the gap is an essential issue of current NFV ***,the cumbersomeness of deployment,the water pipe effect of virtual network function(VNF)chains,and the complexity of the system software stack together make it tough to figure out the cause of low performance in the NFV *** pinpoint the NFV system performance,we propose NfvInsight,a framework for automatic deployment and benchmarking VNF *** framework tackles the challenges in NFV performance *** framework components include chain graph generation,automatic deployment,and fine granularity *** design and implementation of each component have their *** the best of our knowledge,we make the first attempt to collect rules forming a knowledge base for generating reasonable chain *** deploys the generated chain graphs automatically,which frees the network operators from executing at least 391 lines of bash commands for a single *** diagnose the performance bottleneck,NfvInsight collects metrics from multiple layers of the software ***,we collect the network stack latency distribution ingeniously,introducing only less than 2.2%*** showcase the convenience and usability of NfvInsight in finding bottlenecks for both VNF chains and the underlying *** our framework,we find several design flaws of the network stack,which are unsuitable for packet forwarding inside one single server under the NFV *** optimization for these flaws gains at most 3x performance improvement.

关键词： network function virtualization(NFV) service chain performance bottleneck network stack latency

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