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橡胶参考资料 1997年第3期27卷 14-28页

作者： m.a.philippe 王克彪

四十多年以来,传统上都是用二异氰酸甲苯酯(TDI)来生产软质泡沫板的。在美国,几乎都是用80:20的2,4和2,6两种TDI的同分异构体的混合物来生产聚醚多元醇型泡沫板。而在另一些国家,也是用65:

关键词：软质聚氨酯泡沫板材甲基苯异氰酸酯泡沫塑料

CURDIS： A template for incremental curve discretization algorithms and its application to conics

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虚拟现实与智能硬件 2024年第5期6卷 358-382页

作者： philippe LATOUR marc VAN DROOGENBROECK Belgium 4000

We introduce CURDIS, a template for algorithms to discretize arcs of regular curves by incrementally producing a list of support pixels covering the arc. In this template, algorithms proceed by finding the tangent quadrant at each point of the arc and determining which side the curve exits the pixel according to a tailored criterion. These two elements can be adapted for any type of curve, leading to algorithms dedicated to the shape of specific curves. While the calculation of the tangent quadrant for various curves, such as lines, conics, or cubics, is simple, it is more complex to analyze how pixels are traversed by the curve. In the case of conic arcs, we found a criterion for determining the pixel exit side. This leads us to present a new algorithm, called CURDIS-C, specific to the discretization of conics, for which we provide all the details. Surprisingly, the criterion for conics requires between one and three sign tests and four additions per pixel, making the algorithm efficient for resource-constrained systems and feasible for fixed-point or integer arithmetic implementations. Our algorithm also perfectly handles the pathological cases in which the conic intersects a pixel twice or changes quadrants multiple times within this pixel, achieving this generality at the cost of potentially computing up to two square roots per arc. We illustrate the use of CURDIS for the discretization of different curves, such as ellipses, hyperbolas, and parabolas, even when they degenerate into lines or corners.

关键词： Computer graphics Curve discretization Conics Rasterization Ellipse drawing Conic spline Conic pencil

The top-order energy of quasilinear wave equations in two space dimensions is uniformly bounded

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Fundamental Research 2024年第2期4卷 270-283页

作者： Shijie Dong philippe G.LeFloch Zhen Lei Southern University of Science and Technology SUSTech International Center for Mathematicsand Department of MathematicsShenzhen 518055China Fudan University School of Mathematical Sciences220 Handan RoadShanghai 200433China Laboratoire Jacques-Louis Lions and Centre National de la Recherche Scientifique Sorbonne Université4 Place JussieuParis 75252France Shanghai Center for mathematical Sciences Shanghai 200433China

Alinhac solved a long-standing open problem in 2001 and established that quasilinear wave equations in two space dimensions with quadratic null nonlinearities admit global-in-time solutions,provided that the initial data are compactly supported and sufficiently small in Sobolev *** this work,Alinhac obtained an upper bound with polynomial growth in time for the top-order energy of the solutions.A natural question then arises whether the time-growth is a true phenomenon,despite the possible conservation of basic *** the present paper,we establish that the top-order energy of the solutions in Alinhac theorem remains globally bounded in time.

关键词： Quasilinear wave equation Global-in-time solution Uniform energy bounds Quadratic null nonlinearity Hyperboloidal foliation method Vector field method

Recent Progress of the Solar Wind magnetosphere Ionosphere Link Explorer (SmILE) mission

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空间科学学报 2024年第4期44卷 692-698页

作者： WANG Chi ESCOUBET philippe FORSYTH Colin LI Jing AGNOLON David State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190 European Space Agency/European Space Research and Technology Centre Noordwijk 2201 AZ mullard Space Science Laboratory University College LondonLondon RH56 NT

The SmILE(Solar wind magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European Space Agency(ESA),aiming to understand the interaction of the solar wind with the Earth’s magnetosphere in a global *** of may 2024,the SmILE mission is in phase-D with an expected launch date of September *** report summarizes developments in the mission during the past two years.

关键词： SmILE Soft X-ray Imager Ultra-Violet Imager Light Ion Analyzer magnetometer

Why people should run after positive affective experiences instead of health benefits

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Journal of Sport and Health Science 2024年第4期13卷 445-450页

作者： Silvio maltagliati philippe Sarrazin Layan Fessler mael Lebreton Boris Cheval University of Grenoble Alpes SENSGrenoble 38000France Paris School of Economics Paris 75014France Swiss Center for Affective Sciences University of GenevaGeneva 1202Switzerland Laboratory for Behavioral Neurology and Imaging of Cognition Department of Fundamental NeurosciencesUniversity of GenevaGeneva 1202Switzerland Laboratory for the Study of Emotion Elicitation and Expression(E3Lab) Department of PsychologyUniversity of GenevaGeneva 1202Switzerland

Over time,physical activity(PA)has shifted from being a necessity to being an *** a result,levels of PA have sharply decreased.1 Today,we are facing a worldwide pandemic of physical inactivity,with one death every 6 s attributed to insufficient PA.2 To counteract this trend,a tremendous effort is being made to promote regular PA across the lifespan,mainly through the dissemination of knowledge about the health benefits of accumulating sufficient PA.

关键词： sharply benefits attributed

Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan mg-air batteries

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Journal of magnesium and Alloys 2024年第2期12卷 825-839页

作者： Yaqing Zhou Fan Sun Gunahua Lin Sandrine Zanna Antoine Seyeux philippe marcus Jolanta´Swiatowska Chimie ParisTech-CNRS PSL UniversityInstitut de Recherche de Chimie Paris11 rue Pierre et Marie CurieParis 75005France

mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and ***,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of mg-air batteries and leads to poor specific capacity,low energy density,and low ***,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time mg-air batteries is *** resulting mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid *** thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of mg anode in this optimized electrolyte for mg-air batteries.

关键词： Acetic acid additive in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film Surface characterization Hydrogen evolution

Origin and diversification of maize: Two teosintes but different contributions

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molecular Plant 2024年第2期17卷 233-235页

作者： Jonathan Acosta-Bayona Gloria Leon-martinez Jean-philippe Vielle-Calzada Grupo de Desarrollo Reproductivo y Apomixis UGA Laboratorio Nacional de Genomica para la BiodiversidadCinvestav IrapuatoIrapuato Gto CP36825Mexico

The unique topographic,climatic,and latitudinal heterogeneity of mesoamerica is crucial to understanding the evolutionary emergence of one of the richest cultural and biological regions in the planet and its impact on food *** divided between two regions of large biodiversity-lowland tropical or coastal zones and temperate or subtropical highlands sculpted by parallel sierras and their central plateau-the mexican territory harbors more than 2000 endemic monocotyledonous species,including several hundred grasses(Poaceae),particularly those belonging to the genus Zea,composed of maize(Zea mays ***)and its wild relatives,collectively referred as teosintes.

关键词： collective planet harbor

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碱改性铜锰尖晶石室温催化氧化空气中甲醛

Chinese Journal of Catalysis 2024年第5期60卷 337-350页

作者： Yongbiao Hua Kumar Vikrant Ki-Hyun Kim philippe m.Heynderickx Danil W.Boukhvalov 汉阳大学土木与环境工程系韩国首尔根特大学国际校区环境与能源研究中心催化与表征材料工程韩国仁川根特大学生物科学工程学院绿色化学与技术系比利时根特京林业大学理学院材料物理与化学研究所江苏南京210037 拉尔联邦大学物理与技术研究所俄罗斯叶卡捷琳堡

甲醛(FA)作为一种有致癌风险的有害污染物,在室内环境中普遍存在.为了高效去除甲醛,催化氧化技术成为了一种既经济又节能的选择,它不仅能降低材料成本(例如避免使用贵金属),也能在无光和室温的条件下进行.本文制备了一种成本效益高的碱... 详细信息

甲醛(FA)作为一种有致癌风险的有害污染物,在室内环境中普遍存在.为了高效去除甲醛,催化氧化技术成为了一种既经济又节能的选择,它不仅能降低材料成本(例如避免使用贵金属),也能在无光和室温的条件下进行.本文制备了一种成本效益高的碱改性锰酸铜尖晶石(Cumn^(2)O_(4))催化剂,并用于甲醛催化氧化反应中.实验结果表明,采用碱(1 mol L^(-1)氢氧化钾)改性的Cumn^(2)O_(4)(1-Cumn^(2)O_(4))作为催化剂,在室温条件下,当甲醛浓度为50 ppm,气体空速为4777 h^(-1)时,甲醛转化率(XFA)达到100%;此外,在甲醛转化率为10%时,其稳态反应速率达到了8.18×10^(-2) mmol g^(-1) h^(-1).原位漫反射红外傅立叶变换光谱结果表明,在催化剂的作用下,甲醛分子经过二氧亚甲基和甲酸酯中间体的转化,最终被氧化为水和二氧化碳.进一步结合密度泛函理论模拟发现,1-Cumn^(2)O_(4)具有较高的催化氧化甲醛性能,可归因于甲醛分子更牢固地吸附在1-Cumn^(2)O_(4)表面,甲醛吸附所需的能量较低,以及最终产物从催化剂表面脱附所需的能量也较低的综合效应.本研究为在无光和室温条件下,高效去除空气中甲醛提供了新型高效、成本效益高且无需贵金属的催化剂,从而为室内空气净化提供了新的科学见解.

关键词：甲醛碱修饰锰酸铜尖晶石催化氧化室内空气

Anomalous negative magnetoresistance in quantum dot Josephson junctions with Kondo correlations

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Science China(Physics,mechanics & Astronomy) 2024年第8期67卷 3-13页

作者： mingtang Deng Chunlin Yu Guangyao Huang Rosa López philippe Caroff Sepideh Ghalamestani Gloria Platero Hongqi Xu Institute for Quantum Information&State Key Laboratory of High Performance Computing College of Computer Science and TechnologyNational University of Defense TechnologyChangsha 410073China NanoLund and Division of Solid State Physics Lund UniversityLund S-22100Sweden China Greatwall Quantum Laboratory Changsha 410006China Institut de Física Interdisciplinària i de Sistemes Complexos IFISC Palma de Mallorca E-07122Spain Instituto de Ciencia de materiales de madrid Madrid 28049Spain Beijing Key Laboratory of Quantum Devices Key Laboratory for the Physics and Chemistry of Nanodevicesand Department of ElectronicsPeking UniversityBeijing 100871China Beijing Academy of Quantum Information Sciences Beijing 100193China Hefei National Laboratory Hefei 230088China

The interplay between superconductivity and the Kondo effect has stimulated significant interest in condensed matter *** compete when their critical temperatures are close and can give rise to a quantum phase transition that can mimic majorana zero ***,we have fabricated and measured Al-InSb nanowire quantum dot-Al *** the Kondo regime,a supercurrent-induced zero-bias conductance peak *** zero-bias peak shows an anomalous negative magnetoresistance(NmR)at weak magnetic *** attribute this anomalous NmR to quasiparticle trapping at vortices in the superconductor leads as a weak magnetic field is *** trapping effect lowers the quasiparticle-caused dissipation and thus enhances the Josephson *** work connects the vortex physics and the supercurrent tunneling in Kondo regimes and can help further understand the physics of Josephson quantum dot system.

关键词： quantum dot Kondo correlation InSb nanowire quasiparticle trapping

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multi-scale persistent spatiotemporal transformer for long-term urban traffic flow prediction

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Journal of Electronic Science and Technology 2024年第1期22卷 53-69页

作者： Jia-Jun Zhong Yong ma Xin-Zheng Niu philippe Fournier-Viger Bing Wang Zu-kuan Wei School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China College of Computer Science&Software Engineering Shenzhen UniversityShenzhen518060China School of Computer Science Southwest Petroleum UniversityChengdu610500China

Long-term urban traffic flow prediction is an important task in the field of intelligent transportation,as it can help optimize traffic management and improve travel *** improve prediction accuracy,a crucial issue is how to model spatiotemporal dependency in urban traffic *** recent years,many studies have adopted spatiotemporal neural networks to extract key information from traffic ***,most models ignore the semantic spatial similarity between long-distance areas when mining spatial *** also ignore the impact of predicted time steps on the next unpredicted time step for making long-term ***,these models lack a comprehensive data embedding process to represent complex spatiotemporal *** paper proposes a multi-scale persistent spatiotemporal transformer(mSPSTT)model to perform accurate long-term traffic flow prediction in *** adopts an encoder-decoder structure and incorporates temporal,periodic,and spatial features to fully embed urban traffic data to address these *** model consists of a spatiotemporal encoder and a spatiotemporal decoder,which rely on temporal,geospatial,and semantic space multi-head attention modules to dynamically extract temporal,geospatial,and semantic *** spatiotemporal decoder combines the context information provided by the encoder,integrates the predicted time step information,and is iteratively updated to learn the correlation between different time steps in the broader time range to improve the model’s accuracy for long-term *** on four public transportation datasets demonstrate that mSPSTT outperforms the existing models by up to 9.5%on three common metrics.

关键词： Graph neural network multi-head attention mechanism Spatio-temporal dependency Traffic flow prediction