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材料研究学报 2000年第4期14卷 438-444页

作者：胡社军刘正义魏兴钊曾德长 f.r. de boer K.H.J.Buschow 广东工业大学华南理工大学 Van der Waals-Zeeman Institute The University of Amsterdam

用真空电弧熔炼了Ｃｅ２ＣＯ１７－ｘＳｉｘ化合物，研究了化合物的结构与内禀磁性。研究了Ｓｉ原子在Ｃｏ次晶格四种晶位的择优占位与Ｃｏ次晶格磁晶各向导性的关系，结果表明，１８ｈ晶位对Ｃｏ次晶格磁晶各向异性的负贡献起重要作用。

关键词：磁晶各向异性铈-钴永磁材料结构

Influence of Non-Magnetic Substitutional Atoms on Spontaneous Moment and Curie Temperature of Ce_2Co_(17) Compounds

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Journal of.r.re Earths 2002年第4期20卷 273-277页

作者：胡社军刘正义 de boer f.r.Buschow K H J faculty of Materials and Energy Guangdong University of Technology Guangzhou 510643 China

The structure and magnetic properties of Ce 2Co 17-xM x(M=Ga,Al and Si) compounds f.r.M concentrations up to x=5 were studied by means of X-ray dif.r.ction and magnetic measurements. The experimental results show that the Curie temperatures and Co spontaneous magnetization decrease significantly with increasing the addition of non-magnetic substitutional atoms, and that Si which has a minimum solid solubility in Ce 2Co 17 causes a largest reduction of Curie temperature, spontaneous magnetization and moment per Co atom compared with Ga and Al.

关键词： rare earths Ce 2Co 17 compounds Curie temperature spontaneous magnetization

Endo-microscopy beyond the Abbe and Nyquist limits

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Light(Science & Applications) 2020年第1期9卷 1246-1257页

作者： Lyubov V.Amitonova Johannes f.de boer LaserLaB Department of Physics and AstronomyVrije Universiteit AmsterdamDe Boelelaan 10811081 HV AmsterdamThe Netherlands Advanced research Center f.r.Nanolithography(ArCNL) Science Park 1061098 XG AmsterdamThe Netherlands

f.r.several centuries,f.r.field optical microscopy has remained a key instrument in many scientific disciplines,including physical,chemical,and biomedical ***,f.r.field imaging has many limitations:the spatial resolution is controlled by the dif.r.ction of light,and the imaging speed follows the Nyquist–Shannon sampling *** recent development of super-resolution techniques has pushed the limits of spatial ***,these methods typically require complicated setups and long acquisition times and are still not applicable to deeptissue ***,we report imaging through an ultra-thin fibre probe with a spatial resolution beyond the Abbe limit and a temporal resolution beyond the Nyquist limit simultaneously in a simple and compact *** use the random nature of mode coupling in a multimode fibre,the sparsity constraint and compressive sensing *** new approach of super-resolution endo-microscopy does not use any specific properties of the fluorescent label,such as depletion or stochastic activation of the molecular fluorescent state,and theref.r. can be used f.r.label-free *** demonstrate a spatial resolution more than 2 times better than the dif.r.ction limit and an imaging speed 20 times faster than the Nyquist *** proposed approach can significantly expand the realm of the application of nanoscopy f.r.bioimaging.

关键词： beyond limit fibre

A numerical model to simulate the transient frictional viscoelastic sliding contact

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friction 2024年第2期12卷 319-339页

作者： Dongze WANG Gregory de boer Anne NEVILLE Ali GHANBArZAdeH School of Mechanical Engineering University of LeedsLeeds LS29JTUK

Sliding motion has always been one of the major concerns when it comes to the analysis of viscoelastic contact problems.A new model simulating the transient sliding contact of smooth viscoelastic surfaces is developed in this *** taking the dry contact friction and the coupling between shear tractions and normal pressure into account,the effect of the early partial slip period,which is often neglected in the study of viscoelastic sliding contact problems,is investigated *** with solutions based on the frictionless assumption,the steady-state pressure profile is found to be slightly diff.r.nt under the effect of the partial slip regime,including a lower peak pressure and the shift of the contacting region in the direction opposite to the sliding ***,the time required f.r.the viscoelastic contact to reach its steady state is delayed owing to the partial slip period preceding the global sliding motion.

关键词： contact mechanics frictional sliding viscoelasticity viscoelastic friction

Wintering Swan Geese maximize energy intake through substrate f.r.ging depth when feeding on buried Vallisneria natans tubers

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Avian research 2019年第2期10卷 163-170页

作者： Yan Chen Yong Zhang Lei Cao Willem f.de boer Anthony D.fox School of Life Sciences University of Science and Technology of ChinaHefei 230027China Co-Innovation Center f.r.Sustainable f.r.stry in Southern China College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China research Center f.r.Eco-Environmental Science Chinese Academic of Sciences18 Shuangqing RoadBeijing 100085China University of Chinese Academy of Sciences 19 Yuquan RoadShijingshan DistrictBeijing 100049China resource Ecology Group Wageningen UniversityDroevendaalsesteeg3a6708 PB WageningenThe Netherlands department of Bioscience Aarhus UniversityKalφGrenavej 148410 RφndeDenmark

Background: f.r.ging theory predicts that animals select patches that off.r.the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining animal feeding patch selection. f.r.waterfowl f.r.ging on buried aquatic plant tubers, the distribution and biomass of these plant organs vary with depth in the substrate. Since excavation costs also increase with depth, the energy intake of the animals f.r.ging on these plants is highly sediment depth dependent. Methods: Here, using observations of Swan Geese (Anser cygnoides) f.r.ging on Vallisneria natans tubers, we test our hypothesis that geese feeding on tubers buried at intermediate sediment depth maximize their daily energy intake because of the interaction between tuber size and abundance with depth. To do this, we measured the distribution patterns of buried Vallisneria tubers under both undisturbed conditions and post-exploitation by geese (i.e. giving-up conditions). We investigated the relationship between tuber size and burial depth, and total tuber biomass within each sediment layer in undisturbed and exploited plots. finally, we compared modelled Swan Goose daily energy intake feeding on Vallisneria tubers buried at diff.r.nt sediment layers (1–10, 11–20 and 21–30 cm below the surface). results: Dry weight of Vallisneria tubers linearly increased with burial depth, while average total dry weight density of tubers showed a unimodal relationship, peaking at intermediate levels. Not surprisingly, Swan Geese f.r.ged most intensively on tubers buried at intermediate sediment depths, where they maximize their daily energy intake. Our results support our hypothesis that Swan Geese feeding on tubers at intermediate depths maximize their daily energy intake. Conclusions: Our study is the f.r.t to quantify f.r.ging strategies of Swan Geese during the wintering period, emphasizing the importance of plant traits on f.r.ging selection of belowground f

关键词： Energetic trade-off Optimal f.r.ging Shengjin Lake Substrate Tuber burial depth Yangtze river

responses of breeding waterbird communities to environmental changes in subsidence wetlands in the North China Plain

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Avian research 2023年第3期14卷 336-344页

作者： Guangyao Wang Jinming Zhao Weiqiang Li Xiangrong Song Yong Zhang Chunlin Li Willem f.de boer School of.r.sources and Environmental Engineering Anhui UniversityHefei230601China School of Life Science Huaibei Normal UniversityHuaibei235000China College of Biology and the Environment Nanjing Forestry UniversityNanjing210037China Anhui Province Key Laboratory of Wetland Ecosystem Protection and restoration Anhui UniversityHefei230601China Wildlife Ecology and Conservation Group Wageningen University&Research6708PBWageningenthe Netherlands

In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative ***,waterbirds are facing various threats in these artificial wetlands,due to dramatic environmental changes induced by anthropogenic *** the effects of these changes on the temporal dynamics of the waterbird communities can help understand how waterbirds adapt to environmental changes and thus f.r.ulate effective management and conservation *** this study,we carried out field surveys on waterbirds and environmental factors across 20 subsidence wetlands created by underground coal mining in the Huainan coal mining area in the breeding seasons of 2016 and *** predicted that the waterbird assemblages(i.e.,number of individuals,species richness,Shannon-Wiener diversity,Pielou evenness and species composition) diff.r.d between the two years,and that these diff.r.nces were correlated with the temporal changes in environmental *** the surveyed wetlands,we recorded 26 waterbird species in 2016 and 23 in *** individual wetlands,the number of waterbird individuals and species richness increased by 71.6% and 20.1%,respectively,over the five years,with no changes in Shannon-Wiener diversity and Pielou *** overall increase in the number of bird individuals was mainly caused by an increase in vegetation gleaners and gulls that adapt well to anthropogenic *** species composition was significantly diff.r.nt between the two years,which was mainly caused by changes in the number of individuals of dominant species under influence of changes in human *** most wetlands,the temporal pairwiseβ-diversities could be explained by species turnover rather than nestedness,probably due to high mobility of waterbird species and dramatic changes in local *** study suggests that waterbird communities could respond to environmental changes in subsidence wetlands,

关键词： Artificial wetlands Environmental changes Subsidence wetlands Waterbird community

Improving the quantification of waterfowl migration with remote sensing and bird tracking

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Science Bulletin 2015年第23期60卷 1984-1993页

作者： Yali Si Qinchuan Xin Herbert H.T.Prins Willem f.de boer Peng Gong Ministry of Education Key Laboratory f.r.Earth System Modeling Center for Earth System Science Tsinghua University Joint Center f.r.Global Change Studies resource Ecology Group Wageningen University

Accurately quantifying waterfowl migration patterns is pertinent to monitor ecosystem health and control bird-borne infectious diseases. In this review, we summarize the current understanding of the environmental mechanisms that drive waterfowl migration and then investigate the effect of intra- and inter-annual change in food supply and temperature(e.g., climate change) on their migration patterns. recent advances in remote sensing and animal tracking techniques make it possible to monitor these environmental factors over a wide range of scales and record bird movements in detail. The synergy of these techniques will facilitate substantial progress in our understanding of the environmental drivers of bird migration. We identify prospects f.r.future studies to test existing hypotheses and develop models integrating up-todate knowledge, high-resolution remote sensing data and high-accuracy bird tracking data. This will allow us to predict when waterfowl will be where, in response to shortand long-term global environmental change.

关键词： Waterfowl migration · Environmentaldrivers · Phenology · Stopover ·remote sensing ·Bird tracking

demonstration of tantalum as a structural material f.r.MEMS thermal actuators

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Microsystems & Nanoengineering 2021年第1期7卷 85-97页

作者： Longchang Ni ryan M.Pocratsky Maarten P.de boer CMU Mechanical Engineering dept. 5000 Forbes Ave.PittsburghPA 15213USA Present address:fischione Instruments 9003 Corporate CirExportPA 15632USA

This work demonstrates the processing,modeling,and characterization of nanocrystalline refractory metal tantalum(Ta)as a new structural material f.r.microelectromechanical system(MEMS)thermal actuators(TAs).Nanocrystalline Ta films have a coefficient of thermal expansion(CTE)and Young’s modulus comparable to bulk Ta but an approximately ten times greater yield *** mechanical properties and grain size remain stable after annealing at temperatures as high as 1000°*** has a high melting temperature(Tm=3017℃)and a low resistivity(ρ=20µΩcm).Compared to TAs made from the dominant MEMS material,polycrystalline silicon(polysilicon,Tm=1414℃,ρ=2000µΩcm),Ta TAs theoretically require less than half the power input f.r.the same f.r.e and displacement,and their temperature change is half that of *** TAs operate at a voltage 16 times lower than that of other TAs,making them compatible with complementary metal oxide semiconductors(CMOS).We selectα-phase Ta and etch 2.5-μm-thick sputterdeposited films with a 1μm width while maintaining a vertical sidewall profile to ensure in-plane movement of TA *** is 25 times thicker than the thickest reactive-ion-etchedα-Ta reported in the technical *** stress sensitivities to sputter parameters and to hydrogen incorporation are investigated and ***,a V-shaped TA is fabricated and tested in *** conventional actuation by Joule heating and passive self-actuation are as predicted by models.

关键词： thermal structural thick

Multimodal probe f.r.optical coherence tomography epidetection and micron-scale indentation

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Journal of Innovative Optical Health Sciences 2017年第6期10卷 64-72页

作者： L.Bartolini f.f.r.ldi J.J.A.Weda M.Slaman J.f.de boer D.Iannuzzi department of Physics and Astronomy Vrije Universiteit Amsterdam and LaserLab Amsterdam de Boelelaan 1081 1081HV AmsterdamThe Netherlands

We present a multimodal f.r.ule-top sensor designed to perf.r. the integrated epidetection of Optical Coberence Tomognphy(OCT)depth-profiles and micron-scale indentation by all-optical *** scarning a sample under the probe,we can obtain structural crosse soction images and identify a region of interest in a nonhomogencous ***,with the same probe and setup,we can immediately target that area with a series of spherical indentation measurements,in which the applied load is known with aμN precision,the indentation depth with sub-/m precision and a maximum contact radius of 100 *** to the visualization of the internal structure of the sample,we can gain a better insi ght into the observed mechanical *** ability to impart a small,confined load,and perfomn OCT A scans at the same time,could lead to an altemative,high transverse resolution,Optical Coherence Elastography(OCE)sensor.

关键词： Optomechanical microindentation optical coherence tomography indentation multimodal sensor,epidetection

Conflict resolution f.r.connected automated vehicles at unsignalized roundabouts considering personalized driving behaviours

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Green Energy and Intelligent Transportation 2022年第1期1卷 26-36页

作者： Peng Hang Yiran Zhang Niels de boer Chen Lv School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore Energy research Institute(ErIAN) Nanyang Technological UniversitySingapore

To address the driving conflicts of connected automated vehicles(CAVs)at unsignalized roundabouts,a cooperative decision-making framework is *** personalized driving pref.r.nces of CAVs are considered in the decision-making algorithm,which are reflected by diff.r.nt driving styles.A motion prediction algorithm is used to improve the decision-making *** effect of the motion prediction algorithm on the decisionmaking perf.r.ance is evaluated,including the advancement of driving safety and the computational load f.r.the *** cooperative game theoretic approach is applied to the interaction modelling and collaborative decision making of ***,hardware-in-the-loop(HIL)tests are carried out to evaluate the feasibility and real-time perf.r.ance of the proposed algorithm.

关键词： decision making Connected automated vehicles Conflict resolution Cooperative game theory Unsignalized roundabout