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A New Method for Interpreting the Effective Radius of Curvature: Two-Dimensional Case

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Chinese Physics Letters 1997年第6期14卷 421-423页

作者： cao qing DENG Xi-ming National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

Starting from the vector field theory,the expression of the time average energy flow densityof a paraxial scalar light beam is *** terms of this expression,the x(or y)directional weighted deviation is reasonably defined between the real-beam wavefrontand an imaginary ellipsoidal wavefront which is used to replace the real-beam *** is proved that,when Rx and Ry are just the x and y directional effective radii of curvature,respectively,the ellipsoidal wavefront Le=x^(2)/(2Rx)+y^(2)/(2 Ry)is the best-fit one for the real-beam wavefront ***,the above results are generalized for a general polychrornatic light beams.

关键词： beam directional imaginary

Random Networks and Aligned Arrays of Single-Walled Carbon Nanotubes for Electronic Device Applications

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Nano Research 2008年第4期1卷 259-272页

作者： qing cao John A.Rogers Department of Chemistry University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA Department of Materials Science and Engineering University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA Department of Electrical and Computer Engineering University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA Department of Mechanical Science and Engineering University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA Frederick-Seitz Materials Research Laboratory University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA Beckman Institute for Advanced Science and Technology University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA

Singled-walled carbon nanotubes(SWNTs),in the form of ultrathin fi lms of random networks,aligned arrays,or anything in between,provide an unusual type of electronic material that can be integrated into circuits in a conventional,scalable *** electrical,mechanical,and optical properties of such fi lms can,in certain cases,approach the remarkable characteristics of the individual SWNTs,thereby making them attractive for applications in electronics,sensors,and other *** review discusses the synthesis and assembly of SWNTs into thin film architectures of various types and provides examples of their use in digital electronic circuits with levels of integration approaching 100 transistors and in analog radio frequency(RF)systems with operating frequencies up to several gigahertz,including transistor radios in which SWNT transistors provide all of the active *** results represent important steps in the development of an SWNT-based electronics technology that could fi nd utility in areas such as fl exible electronics,RF analog devices and others that might complement the capabilities of established systems.

关键词： Carbon nanotubes electronic devices thin-film transistors

Evaluation of forecast performance for Super Typhoon Lekima in 2019

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Frontiers of Earth Science 2022年第1期16卷 17-33页

作者： Guomin CHEN Xiping ZHANG qing cao Zhihua ZENG Key Laboratory of Meteorological Disaster(Ministry of Education)/Joint International Research Laboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Shanghai Typhoon Institute of China Meteorological Administration Shanghai 200030China Shanghai Typhoon Institute and Key Laboratory of Numerical Modeling for Tropical Cyclone of China Meteorological AdministrationShanghai 200030China Shanghai Marine Center Meteorological Observatory Shanghai 200030China

The predictions for Super Typhoon Lekima(2019)have been evaluated from official forecasts,global models,regional models and ensemble prediction systems(EPSs)at lead times of 1–5 *** errors from most deterministic forecasts are smaller than their annual mean errors in *** to the propagation speed,the propagation direction of Lekima(2019)was much easier to determine for the official agency and numerical weather prediction(NWP)*** National Centers for Environmental Prediction Global Ensemble Forecast System(NCEP-GEFS),Japan Meteorological Agency Global Ensemble Prediction System(JMA-GEPS)and Meteorological Service of Canada Ensemble System(MSC-CENS)are underdispersed,and the Shanghai Typhoon Institute Typhoon Ensemble Data Assimilation and Prediction System(STI-TEDAPS)is overdispersed,while the ensemble prediction system from European Centre for Medium-Range Weather Forecasts(ECMWF)shows adequate dispersion at all lead *** deterministic forecasting methods underestimated the intensity of Lekima(2019),especially for the rapid intensification period after Lekima(2019)entered the East China *** of the deterministic forecasts performed well at predicting the first landfall point at Wenling,Zhejiang Province with a lead time of 24 and 48 h.

关键词： Typhoon Lekima(2019) track intensity landfall point forecast verification

Two new dammarane-type sapogenins from Gynostemma pentaphyllum

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Chinese Chemical Letters 2011年第12期22卷 1461-1464页

作者： Xia Li Jia qing cao Lin Shi Yu qing Zhao School of Traditional Chinese Materia Medica Shenyang Pharmaceutical UniversityShenyang 110016China College of Food Science Shenyang Agriculture UniversityShenyang 110866China

Two new sapogenins,named（20S,24R）-3β,20,21β,25-tetrahydroxy-21,24-cyclodammarane（1）and 3β-hydroxyetio-17β-dammaranic acid（2）,were isolated from the alkaline hydrolysate of Gynostemma pentaphyllum *** structu... 详细信息

关键词： Gynostemma pentaphyllum Sapogenin Alkaline hydrolysate

Green building materials lit up by electromagnetic absorption function:A review

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Journal of Materials Science & Technology 2022年第17期112卷 329-344页

作者： Ting-Ting Liu Mao-qing cao Yong-Sheng Fang Yu-Hang Zhu Mao-Sheng cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Heilongjiang Institute of Construction Technology Harbin 150025China

Healthy and livable living environments,as well as anti-electromagnetic(EM)radiation buildings,are the long-term goals of human *** introduction of advanced EM wave absorbing materials into buildings is one of the most feasible ways to address the increasing EM pollution in building ***-efficiency,broadband,low-cost and good building performance EM wave absorbing materials,as an important support in the field of sustainable building,has gradually become the hotspot ***,we review the research progress of building materials with EM wave absorption functions,and comb their classification,including cement,concrete,ceramics,and prefabs,especially highlighting the advanced coating *** objectively outline and evaluate the latest technology of building materials with EM wave absorption performance,and discuss the main problems and bottlenecks,highlighting potential research opportunities.

关键词： Anti-electromagnetic radiation building Electromagnetic wave absorption Building materials Green building

Ultra-stable metal nano-catalyst synthesis strategy:a perspective

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Rare Metals 2020年第2期39卷 113-130页

作者： Xiao-qing cao Jun Zhou Song Li Gao-Wu Qin Key Laboratory for Anisotropy and Texture of Materials School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

Supported metal nanoparticles(NPs)as an important heterogeneous catalyst have been widely applied in various industrial *** the catalytic reaction,size of the particles plays an important role in determining their catalytic ***,the small particles exhibit superior catalytic activity in comparison with the larger particles because of an increase in lowcoordinated metal atoms on the particle surface that work as active sites,such as edges and corner ***,these small NPs are typically unstable and tend to migrate and coalescence to reduce their surface free energy during the real catalytic processes,particularly in high-temperature ***,a means to fabricate stable small metal NP catalysts with excellent sinter-resistant performance is necessary for maintaining their high catalytic *** this study,we have summarized recent advances in stabilizing metal NPs from two aspects including thermodynamic and kinetic *** former mainly involve preparing uniform NPs(with an identical size and homogeneous distribution)in order to restrain Ostwald ripening to achieve stability,while the latter primarily involves fixing metal NPs in some special confinement materials(e.g.,zeolites,mesoporous silica and mesoporous carbons),encapsulating NPs using an oxide-coating film(e.g.,forming core-shell structures),or constructing strong metal-support interactions to improve *** the end of this review,we highlight our recent work on the preparation of high-stability metal catalysts via a unique interfacial plasma electrolytic oxidation technology,that is,metal NPs are well embedded in a porous MgO layer that has both high thermal stability and excellent catalytic activity.

关键词： Nano-catalysts Thermal stability Sinterresistant Synthesis strategy

Two new cucurbitane triterpenoids from Momordica charantia L.

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Chinese Chemical Letters 2011年第5期22卷 583-586页

作者： Jia qing cao Yu Zhang Jiong Mo Cui Yu qing Zhao School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Yanbian University Health Science Center Yanbian University Yanji 133000 China

Two new cucurbitane-type triterpenoids,（23E）-5β,19-epoxycucurbita-6,23,25-triene-3β-ol（1） and（19R,23E）-5/β,19-epoxy- 19-ethoxycucurbita-6,23-diene^3β,25-diol（2）,together with three known compounds,have been isolated from the fruit of Momordica charantia *** structures were determined on the basis of spectral *** cytotoxic activity was tested on 5 cancer cell lines,MCF-7,HepG2,Dul45,Colon205 and HL-60 by MTT *** 1,3 and 4 showed weak cytotoxicity.

关键词： Momordica charantia L. Cucurbitane-type Triterpenoid Cytotoxicity

Microstructure and Properties of Fe-Cr-C Hardfacing Alloys Reinforced with TiC-NbC

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Journal of Iron and Steel Research International 2016年第3期23卷 276-280页

作者： Hai-yun LIU Zhi-liang SONG qing cao Shao-ping CHEN qing-sen MENG College of Materials Science and Engineering Taiyuan University of Technology

The hypereutectic Fe-Cr-C hardfacing alloys with different contents of TiB_2 and Nb were prepared by selfshielded flux cored arc *** microstructure of a series of hypereutectic Fe-Cr-C hardfacing alloys added with various TiB_2 and Nb contents was investigated by using optical microscopy（OM）,scanning electron microscopy（SEM）and X-ray diffraction（XRD）.In addition,their Rockwell hardness,microhardness and resistance to abrasive wear were *** results showed that the microstructure of a series of hypereutectic Fe-Cr-C hardfacing alloys consisted mainly of martensite,austenite,primary M7C3 carbides and eutectic M7C3 *** the addition of TiB_2,a new hard-phase TiC was produced in the hardfacing *** in the alloys added with TiB_2 and Nb,a new hard composite phase TiC-NbC was *** microhardness of the matrix was improved by adding TiB_2 and Nb,but the effect on the Rockwell hardness of Fe-Cr-C hardfacing alloys was *** addition of TiB_2 and Nb can also decrease the size of the primary M7C3 carbides and make the primary M7C3 *** a result,the reinforced matrix,the more homogeneous primary M7C3 carbides,and the new hard-phase TiC-NbC all improved the wear resistance of Fe-Cr-C hardfacing alloys.

关键词： Fe-Cr-C hardfacing alloy flux-cored wire titanium diboride niobium wear resistance

Preliminary analysis of two NAC transcription factor expression patterns in Larix olgensis

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Journal of Forestry Research 2022年第2期33卷 601-609页

作者： qing cao Peiqi An Sufang Zhang Junhui Wang Hanguo Zhang Lei Zhang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China Chinese Academy of Forestry Beijing 100000People’s Republic of China

The NAC transcription factor family is plant-specific with various biological ***,there are few studies on the NAC gene involving coniferous *** research and expression analysis of NAC genes in Larix olgensis can be used to analyse the function of the NAC gene in the *** of excellent genetic materials and molecular breeding have been utilized to cultivate high-quality,stress-resistant *** to the transcriptome data for ***,the genes Uni-gene81490 and Unigene70699 with complete ORFs(open reading frames)were obtained by conserved domain analy-sis and named LoNAC1 and LoNAC2,*** cDNAs of LoNAC1 and LoNAC2 were 1971 bp and 1095 bp in length,encoding 656 and 364 amino acids,*** molecular weights of the proteins encoded by the two genes were predicted to be 72.61 kDa and 41.13 kDa,and subcellular localization analysis indicated that the proteins were concentrated in the *** results of real-time quantitative PCR analysis showed that at different growth stages and in different tissues of ***,the relative expression levels of the two NAC genes were highest in the stem,and the expression differences were more obvious in non-lignified *** drought,salt and alkali stress and hormone treatment,expression was induced to different *** expression levels of LoNAC1 and LoNAC2 in semi-lignified *** were higher than in the other two periods(non-lignified and lignified),and expression levels significantly increased under drought and salt *** expression levels changed under hormone *** is speculated that these two genes may not only be related to drought and salt stress and secondary growth but may also be induced by hormones such as abscisic ***,LoNAC1 and LoNAC2 are genetic materials that can be used for molecular breeding of larch.

关键词： Larix olgensis NAC transcription factor Bioinformatics analysis Expression patterns