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Micromechanical analysis of the behavior of stiffclay

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Acta Mechanica sinica 2011年第6期27卷 1013-1022页

作者： Zhen-Yu Yin Ching s. Chang Pierre-yves Hicher Jian-Hua Wang Department of Civil Engineering Shanghai Jiao Tong University 200240 Shanghai China Department of Civil and Environmental Engineering University of Massachusetts Amherst MA 01002 USA Research Institute in Civil and Mechanical Engineering UMR CNRs 6183 Ecole Centrale de Nantes BP 92101 44321 Nantes France

Cementations formed in geological timescale are observed in various stiff clays.A micromechanical stress strain model is developed for modeling the effect of cementation on the deformation behavior of stiff *** proposed approach considers explicitly cementations at intercluster contacts,which is different from conventional *** concept of inter-cluster bonding is introduced to account for an additional cohesion in shear sliding and a higher yield stress in normal compression.A damage law for inter-cluster bonding is proposed at cluster contacts for the debonding process during mechanical *** model is used to simulate numerous stress-path tests on Vallericca stiff *** applicability of the present model is evaluated through comparisons between the predicted and the measured *** order to explain the stress-induced anisotropy arising from externally applied load,the evolution of local stresses and local strains at inter-cluster planes are discussed.

关键词： stiff clay Destructuration Micromechanics Plasticity Induced anisotropy

Optical gravitational wave detectors on the ground and in space:theory and technology

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Research in Astronomy and Astrophysics 2010年第10期10卷 956-1004页

作者： Jean-yves Vinet ARTEMIs Observatoire de la Cte d'Azur Université de Nice-sophia Antipolis 06304 NICE France

Major predictions of General Relativity, unforeseen at the beginning of the preceding century, are now under investigation. The existence of black holes of any mass from tens to billions of solar masses is now established, and the physics around these objects begins to be studied through direct observations in a wide electromagnetic spectrum from visible light to X-rays. General relativity, however, provides an extra medium which carries more information on the regions of intense gravitational field, namely gravitational waves （GWs）. Due to their extremely weak coupling to matter, GWs are precisely generated in those regions of spacetime undergoing strong curvature, which is very exciting for modern astrophysics. On the other hand, this weak coupling makes it difficult for GWs to cause appreciable effects in human made instruments. This is why technology of GW detectors took such a long time to reach a sensitivity level consistent with GW amplitudes predicted by theoretical models of sources. In the present status, apart from resonant solid detectors, two large interferometric antennas （LIGO in the UsA and the French-Italian Virgo） are beginning to produce data, and a joint EsA-NAsA space mission, resulting from a wide effort of European and American groups, is reaching a crucial approval phase. The aim of the present review is to give the theoretical bases of GW detectors using light.

关键词： gravitation -- gravitational waves -- interferometry

Post-translational Regulation of sPX Proteins for Coordinated Nutrient signaling

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Molecular Plant 2019年第8期12卷 1041-1043页

作者： yves Poirier Department of Plant Molecular Biology University of Lausanne1015 LausanneSwitzerland

Proteins containing an sPX domain are involved in numerous aspects of phosphate homeostasis and the response to phosphate ***4 is known to bind to the transcription factor PHR2 in the presenee of inositol polyphosphate,affecting its ability to activate the expression of phosphate-starvation-induced (PsI) *** have evolved mechanisms to coordinate the uptake and utilization of phosphate and *** recent works (Hu et al.,2019;Ruan et al.,2019) have identified different E3 ubiquitin ligases that mediate the degradation of sPX4 under either phosphate-deficient conditions or nitrate-replete *** studies highlight the potential of sPX proteins,E3 ubiquitin ligases,and inositol polyphosphate to regulate distinet nutrient signaling pathways in a coordinated fashion.

关键词： Post-translational Regulation sPX Proteins Coordinated Nutrient signaling phosphate-starvation-induced(PsI)

Modeling Drug Concentration in Blood through Caputo-Fabrizio and Caputo Fractional Derivatives

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Computer Modeling in Engineering & sciences 2023年第6期135卷 2767-2785页

作者： Muath Awadalla Kinda Abuasbeh yves Yannick Yameni Noupoue Mohammed s.Abdo Department of Mathematics and statistics College of ScienceKing Faisal UniversityHafufAl Ahsa31982Saudi Arabia Institute of statistics Biostatistics and Actuarial ScienceFaculty of ScienceUniversite Catholique de LouvainLouvain-La-Neuve1348Belgium Department of Mathematics Hodeidah UniversityAl-Hudaydah3114Yemen

This study focuses on the dynamics of drug concentration in the *** general,the concentration level of a drug in the blood is evaluated by themean of an ordinary and first-order differential *** precisely,it is solved through an initial value *** proposed a newmodeling technique for studying drug concentration in blood *** technique is based on two fractional derivatives,namely,Caputo and Caputo-Fabrizio *** first provided comprehensive and detailed proof of the existence of at least one solution to the problem;we later proved the uniqueness of the existing *** proof was written using the Caputo-Fabrizio fractional derivative and some fixed-point *** via theUlam-Hyers(UH)technique was also *** application of the proposedmodel on two real data sets revealed that the Caputo derivative wasmore suitable in this ***,for the first data set,the model based on the Caputo derivative yielded a Mean squared Error(MsE)of 0.03095 with a corresponding best value of fractional order of derivative of ***-Fabrizio-basedderivative appeared to be the second-best method for the problem,with an MsE of 0.04324 for a corresponding best fractional derivative order of *** the second experiment,Caputo derivative-based model still performed the best as it yielded an MsE of 0.04066,whereas the classical and the Caputo-Fabrizio methods were tied with the same MsE of *** interesting finding was that the MsE yielded by the Caputo-Fabrizio fractional derivative coincided with the MsE obtained from the classical approach.

关键词： Pharmacokinetics caputo fractional derivative stability study Caputo-Fabrizio fractional derivative

Pathology of hepatic iron overload

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World Journal of Gastroenterology 2007年第35期13卷 4755-4760页

作者： yves Deugnier Bruno Turlin Liver Unit and CIC INsERM 0203 Pontchaillou University HospitalRennes 35033France Department of Pathology and INsERM U 522 Pontchaillou University HospitalRennes 35033France

Although progress in imaging and genetics allow for a noninvasive diagnosis of most cases of genetic iron overload, liver pathology remains often useful （1） to assess prognosis by grading fibrosis and seeking for associated lesions and （2） to guide the etiological diagnosis, especially when no molecular marker is available. Then, the type of liver siderosis （parenchymal, mesenchymal or mixed） and its distribution throughout the Iobule and the liver are useful means for suggesting its etiology： HLA-linked hemochromatosis gene （HFE） hemochromatosis or other rare genetic hemochromatosis, nonhemochromatotic genetic iron overload （ferroportin disease, aceruloplasminemia）, or iron overload secondary to excessive iron supply, inflammatory syndrome, noncirrhotic chronic liver diseases including dysmetabolic iron overload syndrome, cirrhosis, and blood disorders.

关键词： Iron Liver Biopsy Hemochromatosis Ferroportin HLA-linked hemochromatosis gene Hepcidin Metabolic syndrome

Trigonometric multiplicative chaos and applications to random distributions

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science China Mathematics 2023年第1期66卷 3-36页

作者： Aihua Fan yves Meyer school of Mathematics and statistics Central China Normal UniversityWuhan 430079China LAMFA CNRSUMR7352University of PicardieAmiens 80039France CMLA ENS-CachanCNRSUniversityof Paris-SaclayParis 91190France

The random trigonometric series∑∞n=1ρn cos(nt+ωn)on the circle T are studied under the conditions∑|ρn|^(2)=∞andρn→0,where{ωn}are independent and uniformly distributed random variables on *** are almost surely not Fourier-stieltjes series but determine *** leads us to develop the theory of trigonometric multiplicative chaos,which produces a class of random *** kernel and the image of chaotic operators are fully studied and the dimensions of chaotic measures are exactly *** behavior of the partial sums of the above series is proved to be *** theory holds on the torus Tdof dimension d≥1.

关键词： multiplicative chaos random Fourier series Hausdorff dimension Riesz potential

Profitability of RE-Technology Regarding the Economic Environment:A Case study of swiss sMEs

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Journal of Electronic science and Technology 2018年第4期16卷 351-366页

作者： Lara Thalmann yves Hertig international institute of management in technology University of Fribourg Fribourg 1700Switzerland

Considering the important changes in the swiss energy sector, especially in renewable energy(RE)technologies, new revenue possibilities for small and medium sized enterprises(sMEs) emerge. However, the adaption of RE-technologies for swiss enterprises relies on tangible financial returns, based on complex calculations. This article analyses business opportunities(BOs) of eight swiss sMEs considering the net present value of RE-investments in an uncertain economic environment. We identify two profitable BOs for swiss sMEs and three which are not profitable. Further, the article demonstrates that the profitability of such investments remains mostly positive even under economic uncertainties. surprisingly the profitability does not change significantly if the sME receives a subsidy or not. The support instrument of the swiss Government has not a ponderous impact on the decision to invest in RE-technologies or not. Therefore, the article emphasizes the importance of including sME in the swiss attempt to decentralize the energy market.

关键词： Net present value renewable energy(RE)-investments sensitivity analysis small and medium sized enterprises(sMEs)

Modeling the effect of wetting on the mechanical behavior of crushable granular materials

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Geoscience Frontiers 2020年第2期11卷 487-494页

作者： Carlos Ovalle Pierre-yves Hicher Research Institute of Mining and Environment(RIME UQAT-Polytechnique) Department of CivilGeological and Mining EngineeringPolytechnique MontrealQuebecCanada GeM UMR CNRs 6183 Ecole Centrale de NantesFrance

It is well known that the compressibility of crushable granular materials increases with the moisture content,due to the decrease of particle strength in a humid *** existing approach to take into account the effect of grain breakage in constitutive modeling consists in linking the evolution of the grain size distribution to the plastic *** how the material humidity can affect this relationship is not clear,and experimental evidence is quite *** on compression tests on dry and saturated crushable sand recently reported by the present authors,a new non-linear relationship is proposed between the amount of particle breakage and the plastic *** expression contains two parameters:(1)a material constant dependent on the grain characteristics and(2)a constant depending on the wetting condition(in this study,dry or saturated).A key finding is that the relationship does not depend on the stress path and,for a given wetting condition,only one set of parameters is necessary to reproduce the results of isotropic,oedometric,and triaxial compression *** relationship has been introduced into an elastoplastic constitutive model based on the critical state concept with a double yield surface for plastic sliding and *** breakage ratio is introduced into the expression of the elastic stiffness,the critical state line and the hardening compression *** stress-strain computations with the model allow the plastic work to be calculated and,therefore,the evolution of particle crushing can be predicted through the proposed non-linear relationship and reintroduced into the constitutive *** predictions of the experimental results in terms of both stress-strain relationships and breakage ratio were obtained.

关键词： Grain crushing Wetting Constitutive modeling

NH_3 Plasma surface Treatments of Engineering Fluoropolymers: A Way to Enhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating

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材料热处理学报 2004年第5B期25卷 1092-1097页

作者： Maurice Romand Marlene Charbonnier yves Goepfert Laboratoire de sciences et Ingenierie des surfaces and Laboratoire de Sciences et Ingenierie des Surfaces andUMR 5180 des Sciences Analytiques Universite Claude Bernard - Lyon 1 69622 Villeurbanne Cedex France

This paper describes the electroless Ni or Cu plating of some fiuoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon() FEP, Nafion(), ACLAR() and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i)the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion in a simple acidic PdCl2 solution (i.e. without using a prior surface sensitization in an acidic snCl2 solution), and finally (iii) the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+2 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (PdO) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPs) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters.

关键词：镍化学镀层铜化学镀层等离子表面处理表面催化 XPs 剥离试验