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Existence Results for a Class of Periodic Evolution Variational Inequalities

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Chinese Annals of Mathematics,Series B 2007年第6期28卷 629-650页

作者： Samir ADLY Daniel GOELEVEN michel thra DMI-XLIM UMR-CNRS 6172Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. IREMIA Université de La Réunion97400 Saint-DenisFrance.

In this paper, using the Brouwer topological degree, the authors prove an existence result for finite variational inequalities. this approach is also used to obtain the existence of periodic solutions for a class of e... 详细信息

关键词： Variational inequalities Differential inclusions Topological degree Guiding functions Periodic solutions

Photometric and Spectroscopic Study of Ten Low Mass ratio Contact Binary Systems:Orbital Stability,O'Connell Effect and Infrared Calcium Line Filling

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Research in Astronomy and Astrophysics 2024年第8期24卷 212-222页

作者： Surjit S.Wadhwa Adam Popowicz raúl michel Petar Kostić Oliver Vince Nick F.H.Tothill Ain Y.De Horta Miroslav D.Filipović School of Science Western Sydney UniversityLocked Bag 1797PenrithNSW 2751Australia Department of Electronics Electrical Engineering and MicroelectronicsSilesian University of TechnologyAkademicka 1644120 GliwicePoland Instituto de Astronomía UNAM.A.P.87722800 EnsenadaBCMéxico Astronomical Observatory Volgina 711060 BelgradeSerbia

Low mass ratio contact binary systems are more likely to have unstable orbits and potentially *** addition,such systems exhibit characteristics such as starspots and high energy emissions(UV)suggestive of chromospheric and magnetic *** curve modeling of ten contact binary systems is *** were found to be of extreme low mass ratio ranging from 0.122 to 0.24 and three were found to be potentially unstable and possible merger *** of the infrared calcium absorption lines is a marker of increased chromospheric *** use the available Large Sky Area Multi-Object Fiber Spectroscopic Telescope spectra along with matched standard spectra(broadened for rotation)to measure the excess filling of the central core depression flux of the two main infrared calcium absorption linesλ8542 andλ*** find that all reported contact binaries have excess filling of the core flux in the infrared calcium *** of the systems reported were also observed by the Galaxy Evolution Explorer mission and we find that all three have features of excess ultraviolet emissions further adding evidence for increased chromospheric activity in low mass ratio contact *** of both orbital stability and absorption line filling is dependent on the determination of geometric and absolute parameters from light curve *** an insignificant number of contact binary light curves exhibit the O’Connell effect,usually attributed to *** discuss the inclusion of starspots in light curve solutions and how they influence the geometric and absolute parameters.

关键词： (stars)binaries eclipsing-techniques photometric-stars chromospheres

Spectroscopic factors of resonance states with the Gamow shell model

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 38-45页

作者： Mengran Xie Jianguo Li Nicolas michel Honghui Li Wei Zuo CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

We provide an investigation of the spectroscopic factor of resonance states in A=5-8 nuclei,utilizing the Gamow shell model(GSM).Within the GSM,the configuration mixing is taken into account exactly with the shell model framework,and the continuum coupling is addressed via the complex-energy Berggren ensemble,which treats bound,resonance,and non-resonant continuum single-particle states on an equal *** a result,both the configuration mixing and continuum coupling are meticulously considered in the *** first calculate the low-lying states of helium isotopes and isotones with the GSM,and the results are compared with that of ab initio no-core shell model(NCSM)*** results indicate that GSM can reproduce the low-lying resonance states more accurately than the *** this,we delve into the spectroscopic factors of the resonance states as computed through both GSM and NCSM,concurrently conducting systematic calculations of overlap functions pertinent to these resonance ***,the calculated overlap function and spectroscopic factor of6He(01+)■νp3/2→^(7)He(3/2_(1)-)with GSM are compared with the results from ab initio NCSM,variational Monte Carlo,and Green’s function Monte Carlo calculations,as well as available experimental *** results assert that wave function asymptotes can only be reproduced in GSM,where resonance and continuum coupling are precisely addressed.

关键词： spectroscopic factor overlap function resonance states continuum coupling isospin symmetry breaking

Demonstrating grating-based phase-contrast imaging of laser-driven shock waves

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Matter and radiation at Extremes 2024年第4期9卷 90-97页

作者： Leonard Wegert Stephan Schreiner Constantin rauch Bruno Albertazzi Paulina Bleuel Eric Frojdh michel Koenig Veronika Ludwig Artem SMartynenko Pascal Meyer Aldo Mozzanica Michael Müller Paul Neumayer Markus Schneider Angelos Triantafyllidis Bernhard Zielbauer Gisela Anton thilo michel Stefan Funk Plasma Physics Department GSI Helmholtzzentrum fur SchwerionenforschungPlanckstraBe 164291 DarmstadtGermany Erlangen Centre for Astroparticle Physics(ECAP) Friedrich-Alexander-Universität Erlangen-NurnbergNikolaus-Fiebiger-StraBe 291058 ErlangenGermany LULI-CNRS CEASorbonne UniversitésEcole PolytechniqueInstitut Polytechnique de ParisF-91120 Palaiseau CedexFrance Paul Scherrer Institut(Psi) Forschungsstrasse 1115232VilligenSwitzerland Karlsruhe Institute of Technology Institute of Microstructure TechnologyHermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany

Single-shot X-ray phase-contrast imaging is used to take high-resolution images of laser-driven strong shock *** a two-grating Talbot interferometer,we successfully acquire standard absorption,differential phase-contrast,and dark-field images of the shocked *** agreement is demonstrated between experimental data and the results of two-dimensional radiation hydrodynamics simulations of the laser-plasma *** main sources of image noise are identified through a thorough assessment of the interferometer’s *** acquired images demonstrate that grating-based phase-contrast imaging is a powerful diagnostic tool for high-energy-density *** addition,we make a novel attempt at using the dark-field image as a signal modality of Talbot interferometry to identify the microstructure of a foam target.

关键词： interaction shock phase

堆石混凝土坝概述及下一代混凝土坝施工技术展望

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Engineering 2024年第1期32卷 99-105页

作者： Feng Jin Duruo Huang michel Lino Hu Zhou Department of Hydraulic Engineering Tsinghua UniversityBeijing 100084China ISL Ingénierie International Commission on Large DamsParis 75016France

Over the past few decades,one of the most significant advances in dam construction has been the inven-tion of the rock-filled concrete(RFC)dam,which is constructed by pouring high-performance self-compacting concrete(HSCC)to fill the voids in preplaced large *** innovative use of large rocks in dam construction provides engineers with a material that requires less cement consumption and hydration heat while enhancing construction efficiency and environmental ***,two fundamental scientific issues related to RFC need to be addressed:namely,the pouring compactness and the effect of large rocks on the mechanical and physical properties of *** article provides a timely review of fundamental research and innovations in the design,construction,and quality control of *** for next-generation concrete dams are discussed from the perspectives of envi-ronmental friendliness,intrinsic safety,and labor savings.

关键词： Rock-filled concrete dam Pouring compactness Effect of large rocks Intelligent quality control Unmanned dam construction

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中国北方盆地大规模铀成矿作用:地层篇

地质学报 2024年第7期98卷 1953-1976页

作者：程银行金若时 michel CUNEY V.A.PETROV 苗培森中国地质调查局天津地质调查中心(华北地质科技创新中心) 天津300170 中国地质调查局铀矿地质重点实验室天津300170 法国洛林大学资源学院法国NancyF54500 俄罗斯科学院矿床地质、岩石学、矿物学和地球化学研究所俄罗斯Moscow119017

“红黑”耦合沉积建造是中国北方中—新生代盆地(简称北方盆地)砂岩型铀矿的重要控矿要素之一,在勘查实践中得到了广泛证实和应用,指导发现找矿靶区和矿产地300余处,在成矿理论方面取得重要进展。本文系统总结了北方产铀盆地的60万余米... 详细信息

“红黑”耦合沉积建造是中国北方中—新生代盆地(简称北方盆地)砂岩型铀矿的重要控矿要素之一,在勘查实践中得到了广泛证实和应用,指导发现找矿靶区和矿产地300余处,在成矿理论方面取得重要进展。本文系统总结了北方产铀盆地的60万余米铀矿岩芯钻探成果,通过典型矿床赋矿层沉积学、地球化学等对比研究,系统分析了北方盆地侏罗系、白垩系、新近系等赋矿层形成的沉积环境、物质组成等,进一步明确了制约成矿流体运移、铀矿物沉淀的赋矿层条件。结果显示:①北方盆地自侏罗纪以来,发育了Ⅰ中侏罗世—晚侏罗世早期(Bathonian-Oxfordian)、Ⅱ早白垩世早期(Valanginian)、Ⅲ早白垩世晚期(Aptian)、Ⅳ晚白垩世早期(Cenomanian)、Ⅴ晚白垩世晚期—早古近纪(Campanian-thanetian)、Ⅵ早新近纪(Aquitanian-Burdigalian)和Ⅶ晚新近纪(ZancleanPiacenzian)7期红层,与下伏富还原性组分的黑色层构成了典型的对偶沉积建造,为北方盆地大规模成矿奠定了赋矿层基础。②地球化学指标显示:红层中Fe^(2+)/Fe^(3+)比值介于0.29~1.47(n=78),黑层Fe^(2+)/Fe^(3+)比值介于0.57~53.96(n=223),赋矿层Fe^(2+)/Fe^(3+)比值介于1.00~26.45(n=52)。赋矿层、黑层Fe^(2+)/Fe^(3+)比值一般大于1,以发育黄铁矿、炭屑、油斑为特征,为相对较还原的环境。红层Fe^(2+)/Fe^(3+)比值一般小于1,以发育钙质结核为特征,为相对较强氧化的环境。③总有机碳含量显示红层为0~0.16%(n=107),含矿层为0.01%~2.65%(n=137),黑层为0.01%~2.66%(n=339),含矿层总有机碳含量略低于黑层,与铀矿的富集沉淀有密切关系。④砂岩型铀矿体呈“板状”或“楔状”产出于黑层顶部的灰色、灰绿色砂岩和细砂岩,甚至泥岩,红层为含氧含铀流体的运移通道,黑层为含氧含铀流体的富集沉淀的化学屏障。因此,北方盆地红层和黑层对偶沉积、旋回充填是大规模铀成矿必要的地层条件,这些认识打破常规思维,“红黑”旋回叠加导致了北方盆地多层成矿的现象,矿体一般呈板状就位于红层和黑层的过渡带,这对深入理解砂岩型铀矿成矿环境、成矿规律及成矿机理等工作和勘查工作部署具有重要实践意义。

关键词：北方中—新生代盆地砂岩型铀矿大规模成矿沉积环境赋矿层

Unraveling the hydrothermal history of the Xinshuijing Na-metasomatite uranium deposit in the Longshoushan metallogenic belt， Northwest China by coupled hydrothermal zircon U–Pb and albite Ar–Ar dating

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Journal of Earth Science 2024年

作者： JUN ZHONG MARK MIHALASKY michel CUNEY SHENG HE JUN-JIE LI National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing， Beijing Research Institute of Uranium Geology International Atomic Energy Agency (IAEA)， Nuclear Fuel Cycle and Materials Section， Division of Nuclear Fuel Cycle and Waste Technology， Vienna International Center Université de Lorraine， GéoRessources CNRS State Key Laboratory of Lithospheric Evolution (SKLLE)， Institute of Geology and Geophysics， Chinese Academy of Sciences

Na-metasomatite uranium deposits are an important type of large-tonnage low-grade uranium deposit. they are characterized by an intimate association between uranium minerals and albite， and by the common development of syn-ore hydrothermal zircons. Similar to other types of uranium deposits， constraining an accurate age of mineralization remains a challenge for the Na-metasomatite type ones. In this study， we present for the first time， an approach that combines age dating results from the syn-ore albites (40Ar-39Ar) and hydrothermal zircons （U-Pb） for a typical Na-metasomatite uranium deposit， the Xinshuijing deposit in the Longshoushan metallogenic belt of northwest China. the hydrothermal zircon U-Pb and albite40Ar-39Ar ages are consistent with each other （378-366 Ma; within error）， but also identical to the previously reported uraninite chemical U-Pb ages （approximately 370 Ma）. the coupled application of hydrothermal zircon U-Pb and albite40Ar-39Ar age dating is thus regarded as a robust approach for constraining the age of mineralization for Na-metasomatite uranium deposits. An age gap of approximately 70 m.y. between uranium mineralization （～ 370 Ma） and host granitoid emplacement （about 440 Ma） suggests no direct genetic linkage between the two. Further exploration in the surrounding metamorphic units is therefore suggested， rather than only focusing on the host granitoids， especially where intensive wallrock alteration and structural features are pervasive. the varied hydrothermal zircon δ18O isotope compositions are attributed to the significant fluid-wallrock interaction during the uranium mineralization， which is consistent with our previous fluid inclusion and geochemical studies. Our study highlights the importance of selecting appropriate isotopic dating methods， which is informed by detailed paragenetic and geochemical analysis of dateable minerals formed before or coeval to the main-stage uranium mineralization. Moreover， it is underlined that the e

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Scalable Jet-Based Fabrication of PEI-Hydrogel Particles for CO2 Capture

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 351-358页

作者： Jiang, Jieke van Daatselaar, Eline Wijnja, Hylke de Koning Gans, Tessa Schellevis, michel Venner, Cornelis H. Brilman, Derk W. F. Visser, Claas Willem Univ Twente Fac Engn Technol Dept Thermal & Fluid Engn Engn Fluid Dynam Grp NL-7500 AE Enschede Netherlands Univ Twente Fac Sci & Technol Sustainable Proc Technol NL-7500 AE Enschede Netherlands

the capture, regeneration, and conversion of CO2 from ambient air and flue gas streams are critical aspects of mitigating global warming. Solid sorbents for CO2 absorption are very promising as they have high mass transfer areas without energy input and reduce emissions and minimize corrosion as compared to liquid sorbents. However, precisely tunable solid CO2 sorbents are difficult to produce. Here, we demonstrate the high-throughput production of hydrogel-based CO2-absorbing particles via liquid jetting. By wrapping a liquid jet consisting of an aqueous solution of cross-linkable branched polyethylenimine (PEI) with a layer of suspension containing hydrophobic silica nanoparticles, monodisperse droplets with a silica nanoparticle coating layer was formed in the air. A stable Pickering emulsion containing PEI droplets was obtained after these ejected droplets were collected in a heated oil bath. the droplets turn into mm-sized particles after thermal curing in the bath. the diameter, PEI content, and silica content of the particles were systematically varied, and their CO2 absorption was measured as a function of time. Steam regeneration of the particles enabled cyclic testing, revealing a CO2 absorption capacity of 6.5 +/- 0.5 mol kg(-1) solid PEI in pure CO2 environments and 0.7 +/- 0.3 mol kg(-1) solid PEI for direct air capture. Several thousands of particles were produced per second at a rate of around 0.5 kg per hour, with a single nozzle. this process can be further scaled by parallelization. the complete toolbox for the design, fabrication, testing, and regeneration of functional hydrogel particles provides a powerful route toward novel solid sorbents for regenerative CO2 capture.

关键词： CO2 capture droplet hydrogel liquid jet particle steam regeneration CARBON-DIOXIDE CAPTURE STEAM REGENEraTION SORBENTS ADSORPTION SILICA GAS SEPAraTION RECOVERY DROPLETS MEthANE

Extraction of the key infrared radiation temperature features concerning stress and crack evolution of loaded rocks

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International Journal of Mining Science and Technology 2024年第08期 1059-1081页

作者： Wei Liu Liqiang Ma michel Jaboyedoff Marc-Henri Derron Qiangqiang Gao Fengchang Bu Hai Sun Key Laboratory of Xinjiang Coal Resources Green Mining (Xinjiang Institute of Engineering) Ministry of Education Xinjiang Key Laboratory of Coal-bearing Resources Exploration and Exploitation Xinjiang Institute of Engineering Xinjiang Engineering Research Center of Green Intelligent Coal Mining Xinjiang Institute of Engineering School of Mines China University of Mining&Technology Institute of Earth Sciences University of Lausanne School of Civil Engineering Liaoning Petrochemical University

the infrared radiation temperature（IRT） variation concerning stress and crack evolution of rocks is a critical focus in rock mechanics domain and engineering disaster warning. In this paper, a methodology to extract the key IRT features related to stress and crack evolution of loaded rocks is ***, the wavelet denoising and reconstruction in thermal image sequence（WDRTIS） method is employed to eliminate temporal noise in thermal image sequences. Subsequently, the adaptive partition temperature drift correction（APTDC） method is introduced to alleviate temperature drift. On this basis,the spatial noise correction method based on threshold segmentation and adaptive median filtering（OTSU-AMF） is proposed to extract the key IRT features associated with microcracks of loaded *** temperature drift correction, IRT provides an estimation of the thermoelastic factor in rocks,typically around 5.29×10-5MPa-1for sandstones. Results reveal that the high-temperature concentrated region in cumulative thermal images of crack evolution（TICE） can elucidate the spatiotemporal evolution of localized damage. Additionally, heat dissipation of crack evolution（HDCE） acquired from TICE quantifies the progressive failure process of rocks. the proposed methodology enhances the reliability of IRT monitoring results and provides an innovative approach for conducting research in rock mechanics and monitoring engineering disasters.

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