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Phenology of high-arctic butterflies and their floral resources： Species-specific responses to climate change

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Current Zoology 2014年第2期60卷 243-251页

作者： toke t.hфye Anne ESKILDSEN Rikke R. hANSEN Joseph J.BOWDEN Niels M.SChMIDt W.Daniel KISSLING Aarhus Institute of Advanced Studies Hoegh-Guldbergs Gade 6B bldgs. 1630-1632 DK-8000 Aarhus C Denmark Department ofBioscience Kalo Aarhus University Grenaivej 14 DK-8410 Ronde Denmark Arctic Research Centre Aarhus University C.F. Mollers Allé 8 bldg. 1110 DK-8000 Aarhus C Denmark Department of Bioscience Aarhus Aarhus University Ny Munkegade bldg. 1540 DK-8000 Aarhus C Denmark Department of Bioscience Aarhus University Frederiksborgvej 399 DK-4000 Roskilde Denmark Institute for Biodiversity and Ecosystem Dynamics (IBED) University of Amsterdam P.O. Box 94248 1090 GE AmsterdamThe Netherlands

Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtually absent. We examined butterfly specimens collected from yellow pitfall traps over 14 years （1996-2009） at Zackenberg in high-arctic, north-east Greenland. Specimens were previously sorted to the family level. We identified them to the species level and examined long-term species-specific phenological responses to recent summer wanning. two species were rare in the samples （Polaris fritillary Boloria polaris and Arctic blue Plebejus glandon） and statistical analyses of phenological responses were therefore restricted to the two most abundant species （Arctic fritillary, B. chariclea and Northern clouded yellow Colias hecla）. Our analyses demonstrated a trend towards earlier flight seasons in B. chariclea, but not in C. hecla. the timing of onset, peak and end of the flight season in B. chariclea were closely related to snowmelt, July temperature and their interaction, whereas onset, peak and end of the flight season in C. hecla were only related to timing of snowmelt. the duration of the butterfly flight season was significantly positively related to the temporal overlap with floral resources in both butterfly species. We further demonstrate that yellow pitfall traps are a useful alternative to transect walks for butterfly recording in tundra habitats. More phenological studies of Arctic arthropods should be carded out at the species level and ideally be analysed in context with interacting species to assess how ongoing climate change will affect Arctic biodiversity in the near future [Current Zoology 60 （2）： 243-251, 2014].

关键词： Arctic Arthropod Flight period Greenland Pitfall trap Zackenberg

Life-Cycle Bearing Capacity for Pre-Stressed t-beams Based on Full-Scale Destructive test

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Structural Durability & health Monitoring 2025年第1期19卷 145-166页

作者： Yushan ye tao Gao Liankun Wang Junjie Ma Yingchun Cai heng Liu Xiaoge Liu China Construction Seventh Engineering Division Corp. Ltd.Zhengzhou450004China School of Water Conservancy and transportation Zhengzhou UniversityZhengzhou450001China

to investigate the evolution of load-bearing characteristics of pre-stressed beams throughout their service life and to provide a basis for accurately assessing the actual working state of damaged pre-stressed concrete t-beams,destructive tests were conducted on full-scale pre-stressed concrete *** on the measurement and ana-lysis of beam deﬂection,strain,and crack development under various loading levels during the research tests,combined with the veriﬁcation coefﬁcient indicators speciﬁed in the codes,the veriﬁcation coefﬁcients of bridges at different stages of damage can be *** results indicate that the t-beams experience complete,incom-plete linear,and non-linear stages during the destructive test *** the complete linear elastic stage,both the deﬂection and bottom strain veriﬁcation coefﬁcients comply with the speciﬁcations,indicating a good structural load-bearing capacity no longer adheres to the code’s *** the non-linear stage,both coefﬁcients exhi-bit a sharp increase,resulting in a further decrease in the structure’s load-bearing *** to the pro-visions of the current code,the beam can be in the incomplete linear stage when both values fall within the code’s speciﬁed *** strain veriﬁcation coefﬁcient sourced from the compression zone at the bottom of theﬂange is not recommended for assessing the bridge’s load-bearing capacity.

关键词： Pre-stressed t-beams whole process destructive test bearing capacity veriﬁcation coefﬁcient

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-tALOOKOLAEI h.GhANDVAR E.JUMAEV S.KhAtIR t.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and technology Solutions Ho Chi Minh City Open University

this paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. the strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. the curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. the accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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EFFECt OF Ce ON OXIDAtION BEhAVIOUR OF Ni_3Al ALLOYS

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Acta Metallurgica Sinica(English Letters) 1997年第1期10卷 74-78页

作者： t.h Xi Z.X. Yuan and Z.S. Yu (Research Institute of Wuhan Iron & Steel (Group) Company, Wuhan 430080, China)(Department of Materials, Wuhan yejin University of Science and technology, Wuhan 430081, China)(Department of Materials Physics, Beijing Universi Research Inst of Wuhan Iron and Steel (Group) Co Wuhan China

the effect of Ce on the oxidation behaviour of undoped and B-doped Ni3 Al has been studied. Ce can refine Al2O3 grains produced in the course of oxidation of polycrystalline Ni3Al, accelerate the diffusion of oxygen along Al2O3 grain boundaries,and promote the growth of Al2O3 grains. As a result, the quantity of less-protective NiO decreases. the oxidation resistance of 0.011% Ce-doped alloy is the best of all Ce-doped Ni3Al alloys. Because B is benefitial to the formation of Al2O3 and Ce can refine Al2O3 grains, the oxidation resistance of the alloy containing both B and Ce is the best.

关键词： Ni_3Al Ce oxidation

Calculation of electric field–temperature (E, t) phase diagram of a ferroelectric liquid crystal near the SmA–SmC_α~* transition

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Chinese Physics B 2018年第3期27卷 444-450页

作者： F trabelsi h Dhaouadi O Riahi t Othman Universite de tunis El-Manar Faculte des Sciences de TunisLaboratoire de physique de la matiere molle et de modelisation electromagnetique(LP3ME)Campus Universitaire Farhat Hached 2092 Tunis Tunisie

In this work we perform a theoretical calculation in order to reconstitute the （E-t） phase diagram of a chiral smectic liquid crystal in the vicinity of the SmA-SmCα＊ transition. this reconstruction is carried out on the basis of a thermo-dynamic calculation of the slope of the curve joining the SmC＊ domain and the unwound SmC＊. An empiric correction of the mean field term of Landau De-Gennes development is necessary to accomplish this reconstruction. thereafter, an experimental validation is performed to verify our calculations.

关键词： field-temperature phase diagram liquid orystal

MICROBRIDGE tEStING OF YOUNG'S MODULUS AND RESIDUAL StRESS OF NICKEL FILM ELECtROPLAtED ON SILICON WAFER

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 247-254页

作者： Y.Zhou C.S.Yang J.A. Chen G.F. Ding L. Wang M.J Wang Y.M Zhang t.h Zhang Key Laboratory for thin Film and Microfabrication of Ministry of Education Research Institute of Micro/Nanometer Science and Technology Shanghai Jiaotong University Shanghai 200030 China State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics The Chinese Academy of Sciences Beijing 100080 China.

Microbridge testing is used to measure the Young's modulus and residual stresses of metallic *** film microbridges with widths of several hundred microns are fabricated by Microelectromechanical *** order to measure the mechanical properties of nickel film microbridges,special shaft structure is designed to solve the problem of getting the load--deflection curves of metal film microbridge by Nanoin--denter XP system with normal Berkovich *** analysis of the micro--bridge load--deflection curve is proposed to evaluate the Young's modulus and residual stress of the films *** calculated results based on the experimental measurements show that the average Young's modulus and residual stress are around 190GPa and 175MPa respectively,while the Young's modulus measured by Nano-hardness method on nickel film with silicon substrate is 186.8±7.34GPa.

关键词： nickel film microbridge MEMS mechanical property loadeflection measurement

Effects of acetic acid on microstructure and electrochemical properties of nano cerium oxide films coated on AA7020-t6 aluminum alloy

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Rare Metals 2009年第1期28卷 98-101页

作者： h. hasannejad t. Shahrabi M. Aliofkhazraei Materials Engineering Department Faculty of EngineeringTarbiat Modares UniversityTehranIran

Nano cerium oxide films were applied on AA7020-t6 aluminum alloy and the effects of acetic acid concentration on the microstructure and electrochemical properties of the coated samples were investigated by using scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and potentiodynamic polarization methods. It.has been found that by increasing the acetic acid/CeCl3·7h2O molar ratio, high uniform and crack-free films with well-developed grains were obtained and grain sizes of the films decreased. Elimination of cracks and decreasing grain size of the nano cerium oxide films caused corrosion resistance to increase.

关键词： nano cerium oxide films acetic acid aluminum alloy electrochemical property microstructure

the existence and stability of traveling waves with transition layers for the S-K-t competition model with cross-diffusion

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Science China Mathematics 2010年第5期53卷 124-147页

作者： Wu YaPing Zhao ye Capital Normal Univ Dept Math Beijing 100048 Peoples R China Beijing Inst Petrochem technol Dept Math & Phys Beijing 102617 Peoples R China

this paper is concerned with the existence and stability of traveling waves with transition layers for a quasi-linear competition system with cross diffusion,which was first proposed by Shegesada,Kawasaki and *** one of the random diffusion rates is small and the cross-diffusion rate is not small,by the geometric singular perturbation method,the existence of traveling waves with transition layers is ***,by the detailed spectral analysis and topological index method,the traveling waves with transition layers are proved to be locally exponentially stable with shift.

关键词： traveling waves existence stability cross-diffusion spectral analysis unstable bundle

the m1A modification of tRNAs:a translational accelerator of t-cell activation

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Cellular & Molecular Immunology 2022年第12期19卷 1328-1329页

作者： Cheng Chen Lilin ye Institute of Immunology Third Military Medical UniversityChongqing400038China

Upon antigen stimulation,naïve t cells exit the quiescent state and undergo rapid clonal expansion and differentiation[1].this cell fate transition requires accelerated protein synthesis,which is regulated at both the transcriptional and translational levels[2,3].Compared with well-documented transcriptional regulatory mechanisms,the translational regulation of t-cell activation has not been fully elucidated.A recent study by Liu et al.

关键词： activation translational accelerator