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Chemical Criteria to Assess Risk of Phosphorus Leaching from Urban Soils

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Pedosphere 2005年第1期15卷 72-77页

作者： ZHANGGan-Lin W.burghardt YANGJin-Ling StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008China DepartmentofAppliedSoilScience UniversityofDuisburg-EssenEssen45117Germany

Soils from urban and suburban areas are normally enriched with phosphorus (P). Sixteen urban soils with a wide range of total P concentrations under typical urban land uses were sampled and analyzed for extractable P concentrations using water, sodium bicarbonate and citric acid. Meanwhile the soils were artificially leached in columns and P concentrations in the leachates were determined. With linear regression a two-stage linear relationship was found to exist between concentrations of P in the leachates …

关键词： assessment leaching phosphorus urban soils

Osteopontin: a leading candidate adhesion molecule for implantation in pigs and sheep

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Journal of Animal Science and Biotechnology 2015年第2期6卷 177-190页

作者： Greg A Johnson Robert C burghardt Fuller W Bazer Department of Veterinary Integrative Biosciences Texas A&M UniversityCollege Station Department of Animal Science Texas A&M UniversityCollege Station

Osteopontin （OPN; also known as Secreted Phosphoprotein 1, SPP1） is a secreted extra-cellular matrix （ECM） protein that binds to a variety of cell surface integrins to stimulate cell-cell and cell-ECM adhesion and communication. It is generally accepted that OPN interacts with apically expressed integrin receptors on the uterine luminal epithelium （LE） and conceptus trophectoderm to attach the conceptus to the uterus for implantation. Research conducted with pigs and sheep has significantly advanced understanding of the role（s） of OPN during implantation through exploitation of the prolonged peri-implantation period of pregnancy when elongating conceptuses are free within the uterine lumen requiring extensive paracrine signaling between conceptus and endometrium. This is followed by a protracted and incremental attachment cascade of trophectoderm to uterine LE during implantation, and development of a true epitheliochorial or synepitheliochorial placenta exhibited by pigs and sheep, respectively. In pigs, implanting conceptuses secrete estrogens which induce the synthesis and secretion of OPN in adjacent uterine LE. OPN then binds to αvβ6 integrin receptors on trophectoderm, and the αvβ3 integrin receptors on uterine LE to bridge conceptus attachment to uterine LE for implantation. In sheep, implanting conceptuses secrete interferon tau that prolongs the lifespan of CL. Progesterone released by CL then induces OPN synthesis and secretion from the endometrial GE into the uterine lumen where OPN binds integrins expressed on trophectoderm （αvβ3） and uterine LE （identity of specific integrins unknown） to adhere the conceptus to the uterus for implantation. OPN binding to the αvβ3 integrin receptor on ovine trophectoderm cells induces in vitro focal adhesion assembly, a prerequisite for adhesion and migration of trophectoderm, through activation of： 1） P70S6K via crosstalk between FRAP1/MTOR and MAPK pathways; 2） MTOR, PI3K, MAPK3/MAPK1 （Erk1/2） and MAPK14 （p38） signalin

关键词： Implantation Integrins Psteoponti Pigs Sheep

Inferring topological transitions in pattern-forming processes with self-supervised learning

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npj Computational Materials 2022年第1期8卷 1970-1981页

作者： Marcin Abram Keith burghardt Greg Ver Steeg Aram Galstyan Remi Dingreville Department of Physics and Astronomy University of Southern CaliforniaLos AngelesCA90089USA Information Sciences Institute University of Southern CaliforniaMarina del ReyCA90292USA Center for Integrated Nanotechnologies Nanostructure Physics DepartmentSandia National LaboratoriesAlbuquerqueNM87185USA

The identification of transitions in pattern-forming processes are critical to understand and fabricate microstructurally precise materials in many application *** supervised methods can be useful to identify transition regimes,they need labels,which require prior knowledge of order parameters or relevant microstructures describing these ***,we develop a self-supervised,neural-network-based approach that does not require predefined labels about microstructure classes to predict process parameters from observed *** show that assessing the difficulty of solving this inverse problem can be used to uncover microstructural *** demonstrate our approach by automatically discovering microstructural transitions in two distinct pattern-forming processes:the spinodal decomposition of a two-phase mixture and the formation of binary-alloy microstructures during physical vapor deposition of thin *** approach opens a path forward for discovering unseen or hard-to-discern transitions and ultimately controlling complex pattern-forming processes.

关键词： alloy microstructure transitions

Friction between a temperature dependent viscoelastic body and a rough surface

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Friction 2016年第1期4卷 50-64页

作者： rainer HEISE Institute for Mechanics Technische Universit(a)t Berlin Straβe des 17.Juni 135 Berlin D-10623 Germany

In this study, we investigate the friction between a one-dimensional elastomer and a one-dimensional rigid randomly rough surface. Special emphasis is laid on the temperature dependence of the elastomer and its effect on the frictional behavior of the contact. The elastomer is modeled as a Kelvin body in a one-dimensional substitute model in the spirit of the method of dimensionality reduction. The randomly rough surface is a self-affine one-dimensional fractal. We provide a short discussion of a conical indenter pressed in a displacement controlled process into an elastomer. These analytical considerations are taken as a basis for the treatment of the randomly rough counter surface in contact to an elastomer with and without temperature dependent viscosity. We identify dimensionless quantities describing this process, introduce a thermal length scale, and give estimates for the coefficient of friction as function of velocity, indentation and thermal quantities.

关键词： elastomer friction temperature dependence coefficient of friction

Stochastic Differential Games with Reflection and Related Obstacle Problems for Isaacs Equations

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Acta Mathematicae Applicatae Sinica 2011年第4期27卷 647-678页

作者： rainer BUCKDAHN Département de Mathématiques Université de Bretagne Occidentale6avenue Victor-le-GorgeuB.P.80929285 Brest cedexFrance Institute for Advanced Study Shangdong UniversityJinan 250100China

In this paper we first investigate zero-sum two-player stochastic differential games with reflection, with the help of theory of Reflected Backward Stochastic Differential Equations （RBSDEs）. We will establish the dynamic programming principle for the upper and the lower value functions of this kind of stochastic differential games with reflection in a straightforward way. Then the upper and the lower value functions are proved to be the unique viscosity solutions to the associated upper and the lower Hamilton-Jacobi-Bettman-Isaacs equations with obstacles, respectively. The method differs significantly from those used for control problems with reflection, with new techniques developed of interest on its own. Further, we also prove a new estimate for RBSDEs being sharper than that in the paper of E1 Karoui, Kapoudjian, Pardoux, Peng and Quenez （1997）, which turns out to be very useful because it allows us to estimate the LP-distance of the solutions of two different RBSDEs by the p-th power of the distance of the initial values of the driving forward equations. We also show that the unique viscosity solution to the approximating Isaacs equation constructed by the penalization method converges to the viscosity solution of the Isaacs equation with obstacle.

关键词： stochastic differential games value function reflected backward stochastic differential equations,dynamic programming principle Isaacs equations with obstacles viscosity solution

Influence of slant of objective on image formation in optical microscopes

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Chinese Optics Letters 2008年第8期6卷 603-606页

作者： rainer Kning Physikalisch-Technische Bundesanstalt Braunschweig Bundesallee 10038116 BraunschweigGermany

A microscope image formation model based on scalar diffraction and Fourier optics has been developed, which takes a slant angle between the optical axis and the observed surface into account. The theoretical investigations of the imaging of line structures using this model show that reflection type microscopes are much stronger influenced by the slant angle than transmission type microscopes. In addition, the slant angle changes the image contrast and the image shape of a line structure, especially its edge. The larger the slant angle, the stronger the decrease of the image contrast, and the less steep the edge slope in both types of microscopes. Furthermore, the larger the numerical aperture of the objective, the less the effect of the slant angle on the line image shape.

关键词： line this

Viscoelasticity and shear resistance at the aggregate scale of structured and organic carbon-free Chernozems

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Pedosphere 2023年第5期33卷 754-764页

作者： Christoph HAAS rainer HORN Philipp SAGGAU rainer DUTTMANN Institute for Plant Nutrition and Soil Science University of KielKiel 24118Germany Department of Geography Division of Landscape Ecology and Geoinformation SciencesUniversity of KielKiel 24118Germany

Soil rheology characterises the flow behaviour of soils at the particle-particle to aggregate *** sweep tests(ASTs)are often the method of choice for parameterizing soil flow properties,such as the shear strain values at the end of the linear viscoelastic range(i.e.,the deformation is mainly elastic)and at the yield point(i.e.,elastic equals plastic deformation).Samples from seven soil profiles and five soil depths of Chernozems,collected in the Maidanetske study area,close to Uman City of Ukraine,were analysed to evaluate the effect of soil organic carbon(SOC)on the parameters related to soil microstructural stability derived from *** organic carbon was removed with H_(2)O_(2)to determine the soil texture-dependent values of soil rheological properties,which were compared to the values determined for samples with intact water-stable *** shear resistance-related parameters increased for aggregated soil samples compared to SOC-free soil samples,indicating an increase in soil stability due to *** contrast,the values of the overall viscoelasticity and the shear strain were reduced for aggregated soil samples,indicating decreased soil *** functions were applied to predict the shear strain-dependent loss and storage moduli and shear stress values as a function of SOC *** particles(630–2000μm)and volumetric water content improved the *** conclude that increased SOC content,through the gluing and cementing effects of SOC and altered aggregate shapes compared to SOC-free soil materials,contributes to higher microstructural ***,the increased water content in the SOC-containing soil samples reversed soil strengthening *** was due to the fact that a more rapid increase in positive water pressure under shear stress weakened the samples and the spherical aggregates began to rotate more easily,thus loosing energy,when compared to platy particles of the SOC-free soil materials.

关键词： aggregation rheology shear strain shear stress soil organic carbon depletion soil stability

Inf-convolution of G-expectations

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Science China Mathematics 2010年第8期53卷 1957-1970页

作者： BUCKDAHN rainer Laboratoire de Math'ematiques CNRS-UMR 6205Universite' de Bretagne Occidentale

In this paper we will discuss the optimal risk transfer problems when risk measures are generated by G-expectations,and we present the relationship between inf-convolution of G-expectations and the infconvolution of d... 详细信息

关键词： inf-convolution G-expectation G-normal distribution G-Brownian motion

Shock Wave Smearing by Passive Control

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Journal of Thermal Science 2006年第1期15卷 43-47,42页

作者： Piotr DOERFFER Oskar SZULC rainer BOHNING IMP PAN Fiszera 14 PL-80 952 Gdansk Poland ISL Universitat Karlsruhe Karlsruhe Germany

Normal shock wave, terminating a local supersonic area on an airfoil, limits its performance and becomes a source of high speed impulsive noise. It is proposed to use passive control to disintegrate the shock wave. Details of the flow structure obtained by this method are studied numerically. A new boundary condition has been developed and the results of its application are verified against experiments in a nozzle flow. The method of shock wave disintegration has been confirmed and detailed analysis of the flow details is presented. The substitution of a shock wave by a gradual compression changes completely the source of the high speed impulsive noise and bears potential of its reduction.

关键词： transonic flows shock wave boundary layer interaction passive control.