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Mathematical Results In Quantum Physics Har/DVD

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Discrete Maximum Principle for Poisson Equation with Mixed Boundary Conditions Solved by hp-FEM

丛书名： With DVD-ROM

2011年

作者： pavel Exner

ISBN: (数字)9789814350365

ISBN: (纸本)9814350354

The volume collects papers from talks given at QMath11 -- Mathematical Results in Quantum Physics, which was held in Hradec Kr??lov??, September 2010. These papers bring new and interesting results in quantum mechanics and information, quantum field theory, random systems, quantum chaos, as well as in the physics of social systems. Part of the contribution is dedicated to Ari Laptev on the occasion of his 60th birthday, in recognition of his mathematical results and his service to the community. The QMath conference series has played an important role in mathematical physics for more than two decades, typically attracting many of the best results achieved in the last three-year period, and the meeting in Hradec Kralove was no exception

关键词： qmath11 conference proceedings physics results quantum mathematical

来源：畅想之星图书光盘版（南... 评论

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Advances in Applied Mathematics and Mechanics 2009年第2期1卷 201-214页

作者： Tomáš Vejchodský pavel Šolín Institute of Mathematics Czech Academy of SciencesŽitná25CZ-11567 Praha 1Czech Republic Department of Mathematics and Statistics University of NevadaRenoUSAInstitute of ThermomechanicsCzech Academy of SciencesDolejˇskova 5Praha 8CZ-18200Czech Republic

We present a proof of the discrete maximum principle(DMP)for the 1D Poisson equation−u"=f equipped with mixed Dirichlet-Neumann boundary *** problem is discretized using finite elements of arbitrary lengths and polynomial degrees(hp-FEM).We show that the DMP holds on all meshes with no limitations to the sizes and polynomial degrees of the elements.

关键词： Discrete maximum principle hp-FEM Poisson equation mixed boundary conditions

Expansion of the hepatocellular carcinoma Milan criteria in liver transplantation: Future directions

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World Journal of Gastroenterology 2018年第32期24卷 3626-3636页

作者： Mihai-Calin pavel Josep Fuster Hepato Bilio Pancreatic Surgery and Transplant Unit Department of Surgery Digestive and Metabolic Diseases Institute Hospital Clínic University of Barcelona Barcelona-Clínic Liver Cancer Group (BCLC) Liver Unit Institut d’Investigacions Biomèdiques August Pii Sunyer (IDIBAPS) CIBEREHD Universitat de Barcelona

Milan criteria are currently the benchmark related to liver transplantation(LT) for hepatocellular carcinoma. However, several groups have proposed different expanded criteria with acceptable results. In this article, we review the current status of LT beyond the Milan criteria in three different scenarios-expanded criteria with cadaveric LT, downstaging to Milan criteria before LT, and expansion in the context of adult living donor LT. The review focuses on three main questions: what would the impact of the expansion beyond Milan criteria be on the patients on the waiting list; whether the dichotomous criteria(yes/no) currently used are appropriate for LT or continuous survival estimations, such as the one of "Metroticket" and whether it should enter into the clinical practice; and, whether the use of living donor LT in the context of expansion beyond Milan criteria is justified.

关键词： Hepatocellular carcinoma Milan criteria Liver transplantation Living donor liver transplantation Expanded criteria Downstaging

Evaluation of Strain Hardening Parameters

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Journal of Iron and Steel Research International 2004年第4期11卷 38-46页

作者： DING Zong-hai pavel Huml YANG Wei Royal Institute of Technology

The plane-strain compression test for three kinds of materials was carried out in a temperature range between room temperature and 400℃.Theσ-εcurves and strain-hardening rate at different temperatures were simulated and a reasonable fit to the experimental data was obtained.A modified model created by data inference and computer simulation was developed to describe the strain hardening at a large deformation,and the predicted strain hardening are in a good agreement with that observed in a large range of *** influences of different parameters on strain hardening behaviour under large deformation were *** temperature increase within the test temperatures for stainless steel 18/8 Ti results in dropping of flow stress and strain-hardening *** favourableγ-fibre texture to obtain high r,the cold rolling was applied at large *** the experimental procedure,the X-ray diffraction test was carried out to compare the strain hardening and microstructure under large deformation for a bcc steel(low carbon steel SS-1142).The results indicate that the high strain-hardening rate possibly occurs when the primary slip plane{110}is parallel to the rolling plane and the strainhardening rate decreases when lots of{110}plane rotate out from the orientation{110}∥RP.

关键词： deformation model strain hardening strain-hardening rate dislocation density friction

Cerium dioxide as a new reactive sorbent for fast degradation of parathion methyl and some other organophosphates

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Journal of Rare Earths 2014年第4期32卷 360-370页

作者： pavel Janos pavel Kuran Martin Kormunda Vaclav Stengl Tomas Matys Grygar Marek Dosek Martin Stastny Jakub Ederer Vera Pilarova Lubos Vrtoch Faculty of the Environment University of Jan Evangelista Purkyne Faculty of Science University of Jan Evangelista Purkyne Institute of Inorganic Chemistry AS CR v.v.i.

Cerium dioxide was used for the first time as reactive sorbent for the degradation of the organophosphate pesticides para-thion methyl, chlorpyrifos, dichlofenthion, fenchlorphos, and prothiofos, as well as of some chemical warfare agents-nerve gases soman and O-ethyl S-[2-（diisopropylamino） ethyl] methylphosphonothioate （VX）. CeO2 specimens were prepared by calcination of basic cerous carbonate obtained by precipitation from an aqueous solution. The CeO2 samples containing certain amounts （1 wt.%-5 wt.%） of the neighboring lanthanides （La, Pr, Nd） were prepared in a similar way from pure lanthanide salts. It was shown that ceria accelerated markedly the decomposition of parathion methyl causing the cleavage of the P-O-aryl bond in the pesticide molecule. A similar reaction mechanism was proposed for the degradation of other organophosphate pesticides and nerve agents. The degradation times （reaction half-times） were in an order of minutes in the presence of CeO2, compared to hours or days under common environ-mental conditions. The reaction in suitable organic solvents allowed conversions of about 90%for parathion methyl loading of 20 mg pesticide/g CeO2 within 2 h with a reactant half-life in the order of 0.1 min. The key parameter governing the degradation efficiency of CeO2 was the temperature during calcination. At optimum calcination temperature （about 773.15 K）, the produced ceria retained a sufficiently high surface area, and attained an optimum degree of crystallinity （related to a number of crystal defects, and thus poten-tial reactive sites）. The presence of other lanthanides somewhat decreased the reaction rate, but this effect was not detrimental and permitted the possible use of chemically impure ceria as a reactive sorbent. A fast organophosphate degradation was demonstrated not only in non-polar solvents （such as heptane）, but also in polar aprotic solvents （acetonitrile, acetone） that are miscible with water. This opens new possibilities for designi

关键词： cerium dioxide carbonate precursor lanthanides organophosphate pesticide parathion methyl chemical warfare agents hydrolysis non-aqueous solvents rare earths

Plant density affects measures of biodiversity effects

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Journal of Plant Ecology 2013年第1期6卷 1-11页

作者： Terezie Stachova pavel Fibich Jan Leps Department of Botany Faculty of ScienceUniversity of South BohemiaBranisovska 3137005 Ceske BudejoviceCzech Republic Institute of Entomology Biology CentreCASBranisovska 3137005 Ceske BudejoviceCzech Republic

Aims:We tested for the effect of final sowing plant density(*** of established seedlings)on the values of biodiversity effects[transgressive overyielding,net effect,complementarity effect(CE)and selection effect(SE),trait-dependent complementarity and dominance effect]in a glasshouse pot ***:We conducted a single-season(4 months)glasshouse *** monocultures and mixtures containing up to four common meadow species from different functional groups were sown and subsequently thinned to five density levels(8–128 individuals per pot,i.e.200–3200 individuals m2).Community functioning was characterized by yield(both living and dead biomass)of all constituent *** Findings:Our results show that plant density(final sowing density in our case,but this finding can be generalized)affects the yields of both monocultures and *** these and their relationships are the basis for calculation of biodiversity effects,these effects also varied along the density *** biodiversity effect,CE and SE all increased with *** net biodiversity effect and the CE switched from negative to quite positive in the four-species *** Fox’s tripartite partitioning,trait-dependent complementarity was minor in comparison to the dominance *** of our experimental species did not follow the density–productivity relationship,called constant final yield(CFY),which was reflected in the biodiversity *** shape of the density–productivity relationship for experimental species affects also the values of biodiversity indices,particularly when species do not follow the CFY *** to our data and recent simulation experiments,the values of commonly used biodiversity effects can be rather misleading if a species has,e.g.a unimodal dependence of yield for the density gradient and the density level used in the experiment is higher than the peak density.

关键词： biodiversity effects plant density constant final yield

Application of Epoxy Coatings to Increase the Efficiency of Wax Oils Production

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1229-1241页

作者： Ilushin pavel Vyatkin Kirill Anton Kozlov Scientific and Educational Center of Geology and Development of Oil and Gas Fields Department of Oil and Gas TechnologiesPerm National Research Polytechnic UniversityPerm614000Russia

When producing hydrocarbons,an important task relates to the optimization of the stock of the producing *** main complications for wells in non-working mode are represented by the formation of asphalt-resinparaffin *** issue is one of the most common problems in the production and transportation of oil.A promising method to deal with these deposits is the application of smooth coatings made of epoxy polymers on the inner surface of the production well *** this work,a number of laboratory studies were carried out on the“Cold Finger”installation to assess the effectiveness of this *** laboratory studies have shown that the efficiency related to smooth coatings is 27%while the resulting thermal conductivity ranges from 0.259 to 0.279 W/(m°C).These results demonstrate that this technology can reduce the amount of organic deposits and increase the temperature of oil.

关键词： Wax deposits smooth coatings production tubing well

Adaptive hp-FEM with Arbitrary-Level Hanging Nodes for Maxwell’s Equations

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Advances in Applied Mathematics and Mechanics 2010年第4期2卷 518-532页

作者： pavel Solin Lenka Dubcova Ivo Dolezel Department of Mathematics and Statistics University of NevadaReno89557USA Institute of Thermomechanics Academy of Sciences of the Czech RepublicNarodni 311720 Praha 1Czech Republic

Adaptive higher-order finite element methods(hp-FEM)are well known for their potential of exceptionally fast(exponential)***,most hp-FEM codes remain in an academic setting due to an extreme algorithmic complexity of hp-adaptivity *** paper aims at simplifying hpadaptivity for H(curl)-conforming approximations by presenting a novel technique of arbitrary-level hanging *** technique is described and it is demonstrated numerically that it makes adaptive hp-FEM more efficient compared to hp-FEM on regular meshes and meshes with one-level hanging nodes.

关键词： hp-FEM arbitrary-level hanging nodes irregular meshes higher-order edge elements Maxwell’s equations

Numerical Modeling of Pulverized Coal Combustion at Thermal Power Plant Boilers

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Journal of Thermal Science 2015年第3期24卷 275-282页

作者： Aliya ASKAROVA Saltanat BOLEGENOVA Valeryi MAXIMOV Meruyert BEKETAYEVA pavel SAFARIK Al-Farabi Kazakh National University Physics and Technical Physics Faculty 050038 Almaty Kazakhstan Czech Technical University in Prague Faculty of Mechanical Engineering 166 07 Praha 6 Czech Republic

The paper deals with development and application the numerical model for solution of processes at combustion chamber of the thermal power plant boiler. Mathematical simulation is based on solution of physical and chemical processes occuring at burning pulverized coal in the furnace model. Three-dimensional flows, heat and mass transfer, chemical kinetics of the processes, effects of thermal radiation are considered. Obtained results give quantitative information on velocity distributions, temperature and concentration profiles of the components, the amount of combustion products including harmful substances. The numerical model becomes a tool for investigation and design of combustion chambers with high-efficiency and reliable operation of boiler at thermal power plants.

关键词： combustion emission modeling thermal power plant