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Reducing uncertainty in species＇ responses to climate change

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Current Zoology 2014年第2期60卷 186-188页

作者： toke t.hФYE Guest Editor Aarhus Institute of Advanced Studies Aarhus University Hoegh-Guldbergs Gade 6B bldgs. 1630-1632 DK-8000 Aarhus C Denmark

According to the fifth assessment report of the Intergovernmental Panel on Climate Change, wanning of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. In the Northern hemisphere, 1983- 2012 was likely the wannest 30-year period of the last 1,400 years （IPCC 2013）. Although some evidence for ecological change associated with recent warming is available from all biomes, general assessments of species＇ responses to climate change remain associated with great uncertainty （Parmesan, 2006; Post et al., 2009b）.

关键词：气候变化不确定性物种反应评估报告气候系统 IPCC 生物群落

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

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

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

Leveraging ROtI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan N.Muafiry teguh N.Pratama Angga Y.Putra Suraina Gatot.h.Pramono Sidik t.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.tresna Asnawi Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management Facilities and Science and technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

this paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of total Electron Content(tEC)change index(ROtI)derived from this *** generate ROtI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROtI maps of Ina-CORS are ***,the Ina-CORS ROtI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROtI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROtI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROtI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of tEC change index(ROtI)map

Chaotic movement of vortices in superconductors of high-t_c superconducting maglev system at a high speed

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Journal of Modern transportation 2012年第2期20卷 70-75页

作者： h.t. LIN Department of Information Management Department of Electrical Engineering Cheng Shiu University Taiwan China

Vortex motion in superconductors of high-to superconducting maglev system is studied by a computational simulation. the vortex system is treated in a similar fashion, as a system where defects are arranged in periodic arrays and driven by an alternating current （AC） field. Computational simulation reveals that due to the high nonlinearity of the vortex-defect interaction, the system shows typical chaotic characters. Effects of the vortex-vortex coupling, the driving frequency, and the vortex viscosity on the vortex motion have been studied to reveal the interaction between the spatial and temporal chaos. It is found that the mean-field approach is a good approximation to describe the vortex motion in one dimensional vortex system under an AC driving field. the vortex motion under the damping mode is a kind of self-organized motion. Lastly, the spatial chaos can dominate the chaotic behavior of the system.

关键词： superconductors vortex motion spatial chaos temporal chaos