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NLO QCD corrections to Bc(B＊c) production around the Z pole at an e＋e- collider

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Science China(Physics,Mechanics & Astronomy) 2018年第3期61卷 34-46页

作者： XuChang zheng ChaoHsi Chang TaiFu Feng Zan pan Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences bering 100049 China China Center of Advanced Science and Technology (World Laboratory) Beijing 100190 China Department of Physics Hebei University Baoding 071002 China

The production of Bc and B＊ mesons at a Z-factory （an e＋e- collider operating at energies around the Z pole） is calculated up to the next-to-leading order （NLO） QCD accuracy. The results show that the dependence of the total cross sections on the renormalization scale/1 is suppressed by the corrections, and the NLO corrections enhance the total cross sections of B,. by 52% and of Bc＊ by 33% when the renormalization scale is taken at μ = 2mb. To observe the various behaviors of the production of the mesons Bc and Bc＊, such as the differential cross section vs. the out-going angle, the forward-backward asymmetry, and the distribution vs. the energy fraction z up to NLO QCD accuracy as well as the relevant K-factor （NLO to LO） for the production, are calculated, and it is pointed out that some of the observables obtained in the present work may be used as a specific precision test of the standard model.

关键词： Bc meson production Z-factory

Molecular dynamics study on the nano-void growth and coalescence at grain boundary

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Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 86-93页

作者： LIN EnQiang NIU LiSha SHI HuiJi duan zheng Applied Mechanics Laboratory School of Aerospace Tsinghua University Beijing 100084 China

Molecular dynamics simulations using embedded atom method (EAM) potential were performed to study nano-void growth and coalescence at grain boundary in face-centered cubic bicrystal copper. Thin-plate specimens subjected to uniaxial tension strain with one-void and two-void at the centered grain boundary were employed to analyze the effect of specimen size, temperature and applied strain rate on the stress-strain response, incipient yield strength and macroscopic effective Young's modulus. The evolutions of dislocations, twin bands and void shapes under different specimen sizes were also presented. The obtained results show that, regardless of the void numbers, the specimen sizes, temperature, the applied strain rate had significant influence on the void shape evolution, stress-strain curve and incipient yield strength, while negligible effects on the macroscopic effective Young's modulus except for the temperature. Moreover, the voids growth rate along the grain boundary was also found to be associated with the specimen sizes.

关键词： bicrystal void growth void coalescence grain boundary molecular dynamics simulations embedded atom method

Effects of indium on precipitation in Al-3.3Cu-0.8Li alloy

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Acta Metallurgica Sinica(English Letters) 2010年第4期23卷 285-292页

作者： zhengrong pan Ziqiao zheng Zhongquan LIAO Shichen LI School of Materials Science and Engineering Central South University Changsha 410083 China

The effects of 0.5 wt pct In on Al-3.3Cu-0.8Li alloy were studied. Instead of T1 （Al2CuLi） phase, there was an unknown cubic phase acting as the dominant precipitates in the In-added alloy in T6 temper, which disappeared in T8 temper. The orientation relationship between this phase and matrix was given by SAEDs：（001）p//（001）α, [010]p//[010]α. Both measuring directly from HREM images or calculating from it＇s FFTs gave an close lattice parameter about 0.83 nm. 3DAP composition analysis revealed the presence of Al, Cu and Li in the atomic percentages： 60%Al, 30%Cu and 10%Li. Thus, this cubic phase is considered to be Li-rich γ1 （Al4Cu9） phase or a new phase designated as X （Al5Cu6Li2）. Different from the traditional report providing heterogeneous nucleation sites for the precipitates, In was detected neither around nor in the cubic phase by EDX and 3DAP.

关键词： Indium Precipitation Microstructure HRTEM 3DAP

3D printed labyrinth multiresonant composite metastructure for broadband and strong microwave absorption

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Science China(Technological Sciences) 2023年第12期66卷 3574-3584页

作者： duan YuBing LIANG QingXuan YANG Zhen WANG Xin LIU pan LI DiChen School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Microwave absorbers(MAs)with broadband and strong microwave absorption capacities are urgently required to meet the demands of complex electromagnetic(EM)***,a novel labyrinth multiresonant metastructure composed of a polyether-ether-ketone/flaky carbonyl iron(PEEK/CIP)magnetic composite was proposed and fabricated via 3D printing technology.A complex multiresonant cavity design was introduced,and the resonant loss area was significantly *** broadband and high-efficiency microwave absorption performances were *** multilayer labyrinth multiresonant metastructure was designed with gradient *** effects of structural parameters on the absorbing properties were investigated and *** and simulations demonstrated the effectiveness of the design *** designed metastructure with a 10 mm thickness exhibited a-10 dB absorption bandwidth at a frequency of 3.78–40 GHz and an absorption bandwidth below-15 dB at 7.5–36.5 ***,an excellent wide-angle absorption performance was observed for different polarization states,including transverse electric(TE)and transverse magnetic(TM)*** combination of a complex multiresonant metastructure design and 3D printing fabrication provides a facile route to considerably extend the absorption bandwidth and strength of electromagnetic *** work is expected to provide a promising strategy for further enhancing microwave absorption performance,and the designed metastructure possesses great application potential in stealth and electromagnetic compatibility technologies.

关键词： labyrinth metastructure multiresonant magnetic composite materials broadband and strong absorption 3D printing

Dendrobium nobile protects against ovalbumin-induced allergic rhinitis by regulating intestinal flora and suppressing lung inflammation

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Chinese Journal of Natural Medicines 2022年第6期20卷 443-457页

作者： duan Fei-Peng LI Yi-Sheng HU Tian-Yong pan Xin-Quan MA Fang FENG Yue QIU Shu-Qi zheng Yi-Qing Institute of Otolaryngology Institute of Hearing and Speech of Sun Yat-sen UniversitySun Yat-sen Me-morial HospitalSun Yat-sen UniversityGuangzhou 510520China Department of Otolaryngology Longgang E.N.T hospital&Shenzhen Key Laboratory of E.N.TInstitute of E.N.TShenzhen 518172China

Antibiotic exposure-induced dysbiosis of the intestinal flora increases the risk of developing allergic ***,regulating the balance of intestinal flora may be useful for preventing and treating allergic ***,the underlying mechanism is *** nobile(Shihu)exhibits anti-inflammatory and immune ***,in this study,we investigated the mechanism via which Shihu may improve allergic *** models of allergic rhinitis with intestinal flora dysbiosis(Model-D,antibiotics induce intestinal flora dysbiosis with ovalbumin-induced allergy)and normal intestinal flora with allergic rhinitis(Model-N,ovalbumin-induced allergy)were *** effect of Shihu on intestinal flora and inflammation caused during allergic rhinitis were *** symptoms,infiltration of hematoxylin and eosin in the lungs and nose,and the release of various factors[interleukin(IL)-2,IL-4,IFN-y,IL-6,IL-10,and IL-17]in the lungs were *** results indicate that intestinal flora dysbiosis exacerbated lung and nose inflammation in allergic ***,treatment with the Shihu extract effectively reversed these ***,the Shihu extract inhibited the PI3K/AXT/mTOR pathway and increased the level of Forkhead box protein in the ***,the Shihu extract reversed intestinal flora dysbiosis at the phylum and genus levels and improved regulator T cell ***,in the Model-D group,the Shihu extract inhibited the decrease in the diversity and abundance of the intestinal *** was performed to determine which intestinal flora was positively correlated with Treg differentiation using Spearman5 s correlation *** conclusion,we showed that Shihu extract restored the balance in intestinal flora and ameliorated inflammation in the lungs of allergic rhinitis mice and predicted a therapeutic new approach using Traditional Chinese Medicine to improve allergic rhinitis.

关键词： Dendrobium nobile(Shihu) Allergic rhinitis Intestinal flora Regulator T cell Inflammation

Nitrogen Deep Placement Combined with Straw Mulch Cultivation Enhances Physiological Traits,Grain Yield and Nitrogen Use Efficiency in Mechanical Pot-Seedling Transplanting Rice

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Rice science 2022年第1期29卷 89-100,I0031页

作者： LI Lin ZHANG zheng TIAN Hua Umair ASHRAF Yousef Alhaj HAMOUD Al Aasmi ALAA TANG Xiangru duan Meiyang WANG Zaiman pan Shenggang State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of AgricultureSouth China Agricultural UniversityGuangzhou 510642China Scientific Observing and Experimental Station of Crop Cultivation in South China Ministry of Agriculture and Rural AffairsGuangzhou 510642China Department of Botany Division of Science and TechnologyUniversity of EducationLahore 54770Pakistan College of Agricultural Science and Engineering Hohai UniversityNanjing 210098China College of Water Conservancy and Civil Engineering South China Agriculture UniversityGuangzhou 510642China Key Laboratory of Key Technology for South Agricultural Machine and Equipment Ministry of EducationGuangzhou 510642China

To assess the effects of straw return coupled with deep nitrogen(N)fertilization on grain yield and N use efficiency(NUE)in mechanical pot-seedling transplanting(MPST)rice,the seedlings of two rice cultivars,i.e.,Yuxiangyouzhan and Wufengyou 615 transplanted by MPST were applied with N fertilizer at 150 kg/hm2 and straw return at 6 t/hm2 in early seasons of 2019 and *** experiment comprised of following treatments:CK(no fertilizer and no straw return),MDS(deep N fertilization and straw return),MBS(broadcasting fertilizer and straw return),MD(deep N fertilization without straw return),MB(broadcasting fertilizer without straw return).Results depicted that the MDS treatment significantly increased the rice yield by 41.69%-72.22%due to total above-ground biomass,leaf area index and photosynthesis increased by 54.70%-55.80%,38.52%-52.17%and 17.89%-28.40%,respectively,compared to the MB *** addition,the MDS treatment enhanced the total N accumulation by 37.74%-43.69%,N recovery efficiency by 141.45%-164.65%,N agronomic efficiency by 121.76%-134.19%,nitrate reductase by 46.46%-60.86%and glutamine synthetase by 23.56%-31.02%,compared to the MB *** average grain yield and NUE in both years for Yuxiangyouzhan were higher in the MDS treatment than in the MD ***,deep N fertilization combined with straw return can be an innovative technique with improved grain yield and NUE in MPST in South China.

关键词： mechanical pot-seedling transplanting nitrogen deep placement nitrogen use efficiency rice straw return

Sensitivity of Potential Evapotranspiration Estimation to the Thornthwaite and Penman–Monteith Methods in the Study of Global Drylands

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Advances in Atmospheric Sciences 2017年第12期34卷 1381-1394页

作者： Qing YANG Zhuguo MA Ziyan zheng Yawen duan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Drylands are among those regions most sensitive to climate and environmental changes and human-induced *** most widely accepted definition of the term dryland is a ratio,called the Surface Wetness Index(SWI),of annual precipitation to potential evapotranspiration(PET)being below *** is commonly estimated using the Thornthwaite(PET Th)and Penman–Monteith equations(PET PM).The present study compared spatiotemporal characteristics of global drylands based on the SWI with PET Th and PET *** showed vast differences between PET Th and PET PM;however,the SWI derived from the two kinds of PET showed broadly similar characteristics in the interdecadal variability of global and continental drylands,except in North America,with high correlation coefficients ranging from 0.58 to *** was found that,during 1901–2014,global hyper-arid and semi-arid regions expanded,arid and dry sub-humid regions contracted,and drylands underwent interdecadal *** was because precipitation variations made major contributions,whereas PET changes contributed to a much lesser ***,distinct differences in the interdecadal variability of semi-arid and dry sub-humid regions were *** indicated that the influence of PET changes was comparable to that of precipitation variations in the global dry–wet transition ***,the contribution of PET changes to the variations in global and continental drylands gradually enhanced with global warming,and the Thornthwaite method was found to be increasingly less applicable under climate change.

关键词： potential evapotranspiration global drylands Thornthwaite Penman–Monteith

Automatic salient object sequence rebuilding for video segment analysis

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Science China(Information Sciences) 2018年第1期61卷 249-260页

作者： Tie LIU Haibin duan Yuanyuan SHANG Zejian YUAN Nanning zheng School of Automation Science and Electrical Engineering Beihang University Information Engineering College Capital Normal University The School of Electronic and Information Engineering Xi'an Jiaotong University

Detection of salient object sequences from video data is challenging when the salient object changes between consecutive frames. In this study, we addressed the salient object sequence rebuilding problem with video segment analysis. We reformulated the problem as a binary labeling problem, analyzed the potential salient object sequences in the video using a clustering method, and separated the salient object sequence from the background by applying an energy optimization method. Our proposed approach determines whether temporal consecutive pixels belong to the same salient object sequence. The conditional random field is then learned to effectively integrate the salient features and the sequence consecutive constraints.A dynamic programming algorithm was developed to resolve the energy minimization problem *** results confirmed the ability of our approach to address the salient object rebuilding problem in automatic visual attention applications and video content analysis.

关键词： salient object video attention sequence segment analysis conditional random model

Monitoring Multi-Temporal Changes of Lakes on the Tibetan Plateau Using Multi-Source Remote Sensing Data from 1992 to 2019:A Case Study of Lake Zhari Namco

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Journal of Earth Science 2024年第5期35卷 1679-1691页

作者： Juan Wu Chang-Qing Ke Yu Cai zheng duan Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural ResourcesSchool of Geography and Ocean ScienceNanjing UniversityNanjing 210023China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023China Guangxi Water and Power Design Institute Co. LtdNanning 530022China Collaborative Innovation Center of South China Sea Studies Nanjing 210023China Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden

Lake level,area and volume are sensitive indicators of climate *** present,many studies have focused on the interannual water balance of lakes,but lake level and area can change remarkably with seasons,especially for lakes with seasonal ice *** Namco,a seasonal frozen lake,was selected as an example to investigate its seasonal water ***-source altimetry and Landsat data were used to obtain the seasonal lake level and area from 1992 to 2019,and seasonal lake volume variations were also *** results indicated the average lake level,area and volume in autumn were the *** lake level,area,and volume experienced three turning points approximately in 2000,2010,and 2016,and showed an overall increasing trend from 1992 to 2019,with slopes of 0.15 m/year,2.17 km^(2)/year,and 0.14 km^(3)/year,*** lake area expanded significantly in autumn,which was related to the abundant *** time of land surface runoff,increased temperature,and evaporation may be the reason for the low lake level and volume in *** precipitation was the dominant factor of water balance,which explained 62.09%,62.43%,and 62.10%of the variations in lake level,area,and volume,respectively.

关键词： lake level lake area lake volume satellite altimetry landsat Zhari Namco hydrogeology