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Journal of Computational mathematics 2010年第4期28卷 430-460页

作者： Irene m.Gamba Sri Harsha Tharkabhushanam Department of mathematics & Institute of Computational Engineering and Sciences University of Texas Austin Institute of Computational Engineering and Sciences University of Texas Austin

The numerical approximation of the Spectral-Lagrangian scheme developed by the authors in [30] for a wide range of homogeneous non-linear Boltzmann type equations is extended to the space inhomogeneous case and several shock problems are benchmark. Recognizing that the Boltzmann equation is an important tool in the analysis of formation of shock and boundary layer structures, we present the computational algorithm in Section 3.3 and perform a numerical study case in shock tube geometries well modeled in for ID in x times 3D in v in Section 4. The classic Riemann problem is numerically analyzed for Knudsen numbers close to continuum. The shock tube problem of Aoki et al [2], where the wall temperature is suddenly increased or decreased, is also studied. We consider the problem of heat transfer between two parallel plates with diffusive boundary conditions for a range of Knudsen numbers from close to continuum to a highly rarefied state. Finally, the classical infinite shock tube problem that generates a non-moving shock wave is studied. The point worth noting in this example is that the flow in the final case turns from a supersonic flow to a subsonic flow across the shock.

关键词： Spectral Numerical methods Lagrangian optimization FFT Boltzmann Trans- port Equation Conservative and non-conservative rarefied gas flows.

Satisfaction with patient-doctor relationships in inflammatory bowel diseases:Examining patient-initiated change of specialist

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World Journal of Gastroenterology 2012年第18期18卷 2212-2218页

作者： Daniel R van Langenberg Jane m Andrews Department of Gastroenterology and Hepatology Royal Adelaide HospitalSchool of MedicineUniversity of AdelaideSouth Australia 5000Australia Department of Gastroenterology and Hepatology Eastern Health Clinical SchoolMonash UniversityVictoria 3128Australia

AIm:To assess the reasons for,and factors associated with,patient-initiated changes in treating specialist in inflammatory bowel diseases(IBD).mETHODS:Prospectively identified IBD patients(n = 256) with ≥ 1 encounter at a metropolitan hospital were surveyed,including whether they had changed treating specialist and *** reasons included loss of confidence,disagreement,and/or personality clash with the ***:Of 162 respondents,70(43%) had ever changed specialists;30/70(43%) for negative reasons,52/70(74%) in the preceding *** with negative reasons for changing(n = 30) were younger(median,35.2 years vs 45.3 years),had higher IBD knowledge(median,5.0 years vs 4.0 years),yet had lower medication adherence and satisfaction scores(median,19.0 years vs 22.0 years,14.0 years vs 16.0 years respectively,mann-Whitney tests,all P mpared to all other responders(n = 132).Patients with a recent change(for any reason) were more likely to have Crohn's disease,currently active disease,previous bowel resection and recent hospitalization [OR 2.6,95% CI(1.3-5.4),2.2(1.0-4.7),5.56(1.92-16.67),2.0(1.3-3.0),eachP mporaneous disease-related factors(recent relapse) which,where modifiable,may enhance patient-doctor relationships and therefore quality of care.

关键词： Inflammatory bowel disease Patient-doctor relationship Quality of care Disease outcomes Quality of life

mining diversity of the natural biorefinery housed within Tipula abdominalis larvae for use in an industrial biorefinery for production of lignocellulosic ethanol

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Insect Science 2010年第3期17卷 303-312页

作者： Dana m. Cook Joy Doran-Peterson microbiology Department University of Georgia Athens Georgia USA

Although they are the largest taxonomic group of animals, relatively few insects have been examined for symbiotic relationships with micro-organisms. However, this is rapidly changing because of the potential for examination of the natural insectmicrobe-lignocellulose interactions to provide insights for biofuel technology. micro-organisms associated with lignocellulose-consuming insects often facilitate the digestion of the recalcitrant plant diet; therefore these microbial communities may be mined for novel lignocellulose-degrading microbes, or for robust and inexpensive biocatalysts necessary for economically feasible biofuel production from lignocellulose. These insect-microbe interactions are influenced by the ecosystem and specific lignocellulose diet, and appre- ciating the whole ecosystem-insect-microbiota-lignocellulose as a natural biorefinery provides a rich and diverse framework from which to design novel industrial processes. One such natural biorefinery, the Tipula abdominalis larvae in riparian ecosystems, is reviewed herein with applications for biochemical processes and overcoming challenges involved in conversion of lignocellulosic biomass to fuel ethanol. From the dense and diverse T. abdominalis larval hindgut microbial community, a cellulolytic bacterial isolate, 27C64, demonstrated enzymatic activity toward many model plant polymers and also produced a bacterial antibiotic. 27C64 was co-cultured with yeast in fermentation of pine to ethanol, which allowed for a 20% reduction of commercial enzyme. In this study, a micro-organism from a lignocellulose-consuming insect was successfully applied for improvement of biomass-to-biofuel technology.

关键词： ethanol hydrolytic enzymes insect-associated microorganisms lignocellulose

Negative Parity Bands and Signature Splitting Inversion in ^80Rb

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Chinese Physics Letters 2003年第11期20卷 1932-1935页

作者：袁观俊杨春祥王月张振龙孟锐 m.Oshima Y.Toh A.Osa m.Koizumi Y.Hatsukawa m.matsuda T.Hagakawa m.m.Ndontcheng 温书贤贺创业竺礼华王治民李广生马瑞刚吴晓光 DepartmentofPhysics JinlinUniversityChangchun130023 JapanAtomicEnergyResearchInstitute TokaiJapan DepartmentofPhysics UniversityofDoualaDoualaCameroun ChinaInstituteofAtomicEnergy Beijing102413

High spin states in 80Rb were studied via the 65Cu+19F, 66Zn+18O and 68Zn+16O reactions. The 75-meV 19F, 76-meV 18O and 80-meV 16O beams were provided by the CIAE HI-13 Tandem accelerator and the JAERI Tandem accelerator. The prompt γ-γ coincidence and the directional correlation from oriented nuclei (DCO) were measured by the detector arrays in CIAE and JAERI. Twenty-three new states with 28 new transitions have been assigned to 80Rb. The states were observed up to spins of 20+ and 22− in the α = 0 branch for the positive and negative parity yrast bands respectively. The negative parity non-yrast bands were significantly extended up to spins of 22− and 15−. The band crossings with frequencies 0.51meV and 0.61meV in the α = 0 cascade were observed for the first time. The signature splitting was observed in both negative parity bands. The signature inversions at spins of about 7 and 15 were observed.

关键词： HIGH-SPIN STATES

mHD flow and heat transfer of micropolar fluid between two porous disks

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Applied mathematics and mechanics(English Edition) 2012年第1期33卷 51-64页

作者： m. ASHRAF A. R. WEHGAL Centre for Advanced Studies in Pure and Applied mathematics Bahauddin Zakariya University Department of mathematics Stockholm University

A numerical study is carried out for the axisymmetric steady laminar incompressible flow of an electrically conducting micropolar fluid between two infinite parallel porous disks with the constant uniform injection through the surface of the disks. The fluid is subjected to an external transverse magnetic field. The governing nonlinear equations of motion are transformed into a dimensionless form through yon Karman＇s similarity transformation. An algorithm based on a finite difference scheme is used to solve the reduced coupled ordinary differential equations under associated boundary conditions. The effects of the Reynolds number, the magnetic parameter, the micropolar parameter, and the Prandtl number on the flow velocity and temperature distributions are discussed. The results agree well with those of the previously published work for special cases. The investigation predicts that the heat transfer rate at the surfaces of the disks increases with the increases in the Reynolds number, the magnetic parameter, and the Prandtl number. The shear stresses decrease with the increase in the injection while increase with the increase in the applied magnetic field. The shear stress factor is lower for micropolar fluids than for Newtonian fluids, which may be beneficial in the flow and thermal control in the polymeric processing.

关键词： mHD flow porous disk micropolar fluid heat transfer microrotation

Screw theoretic view on dynamics of spatially compliant beam

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Applied mathematics and mechanics(English Edition) 2010年第9期31卷 1173-1188页

作者：丁希仑 J.m.SELIG Robotics Institute Beijing University of Aeronautics and Astronautics Faculty of Business Computing and Information ManagementLondon South Bank University

Beams with spatial compliance can be deformed as bending in a plane, twisting, and extending. In terms of the screw theory on rigid body motions, the concept of ＂deflection screw＂ is introduced, a spatial compliant beam theory via the deflection screw is proposed, and the spatial compliance of such a beam system is presented and analysed based on the material theory and fundamental kinematic assumptions. To study the dynamics of the spatially compliant beam, the potential energy and the kinetic energy of the beam are discussed by using the screw theory to obtain the Lagrangian. The Rayleigh-Ritz method is used to compute the vibrational frequencies based on discussions of boundary conditions and shape functions. The eigenfrequencies of the beam with spatial compliance are compared with those of individual deformation cases, pure bending, extension, or torsion. Finally, dynamics of a robot with two spatial compliant links and perpendicular joints is studied using the spatial compliant beam theory. Coupling between the joint rigid body motions and the deformations of spatial compliant links can easily be found in dynamic simulation. The study shows the effectiveness of using the screw theory to deal with the problems of dynamic modeling and analysis of mechanisms with spatially compliant links.

关键词： spatial compliance beam deformation dynamics robot

Rare earth effect of yttrium on formation and property of Cr2O3 oxide film formed on Co-Cr binary alloy

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Progress in Natural Science:materials International 2006年第1期16卷 72-77页

作者： FELIX A. Congrado AROYAVE m. Hayara College of materials Science and Engineering National University of Antiuquia Medellin 23715Colombia

The isothermal oxidizing kinetics of Co-40Cr alloy and its yttrium ion-implanted samples were studied at 1000 ℃ in air by thermal-gravity analysis (TGA). Scanning electronic microscopy (SEm) was used to examine the Cr2O3 oxide film's morphology after oxidation. Secondary ion mass spectrum (SImS) method was used to examine the binding energy change of chromium caused by Y-doping and its influence on formation of Cr2O3 film. Acoustic emission (AE) method was used in situ to monitor the cracking and spalling of oxide films formed on both samples during oxidizing and subsequent air-cooling stages. Theoretical model simulating the film fracture process was proposed to analyze the acoustic emission spectrum both on time domain and on AE-event number domain. It is found that yttrium ion-implantation can remarkably reduce the isothermal oxidizing rate of Co-40Cr and improve the anti-cracking and anti-spalling properties of Cr2O3 oxide film. Reasons for the improvement are mainly that the implanted yttrium can reduce the grain size of Cr2O3 oxide, increase the high temperature plasticity of oxide film, and remarkably reduce the number and size of Cr2O3/Co-40Cr interfacial defects.

关键词： interface binding energy acoustic emission oxidation yttrium.

Towards the development of cavitation technology for upgrading bitumen： Viscosity change and chemical cavitation yield measurements

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Petroleum Science 2017年第2期14卷 404-411页

作者： Deepak m. Kirpalani Dipti Prakash mohapatra Energy mining and Environment Portfolio National Research Council of Canada 1200 Montreal Road Ottawa ON K1A 0R6 Canada

Among the different methods used for reducing viscosity of bitumen,acoustic cavitation during sonication is well *** chemical methods were used to detect the production of reactive species such as hydroxyl radicals and hydrogen peroxide during acoustic cavitation ***,quantification of cavitation yield in sonochemical systems is generally limited to low frequencies and has not been applied to bitumen *** empirical determination of the cavitation yield in midto high-frequency range（378,574,850,992,and1173 k Hz）was carried out by measuring the amount of iodine liberated from the oxidation of potassium iodide（KI）.Further,cavitation yield and the effects of different sonic operating conditions such as power input（16.67%–83.33%）and solute concentration on cavitation yield were carried out in KI solution and sodium carboxymethyl cellulose–water mixture to obtain benchmark changes in rheology and chemistry using these two model *** findings were then applied to bitumen upgrading through *** this study,it was found that the chemical cavitation yield peaked with a sonication frequency of 574 k *** was also found that cavitation yield and viscosity change were correlated directly in bitumen and a 38%lower bitumen viscosity could be obtained by acoustic cavitation.

关键词： Bitumen Cavitation yield CmC-water KI solution Viscosity correlation

The Dual Spaces of Sets of Difference Sequences of Order m and matrix Transformations

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Acta mathematica Sinica,English Series 2007年第3期23卷 521-532页

作者： Eberhard mALKOWSKY m.mURSALEEN Suthep SUANTAI Department of mathematics University of GiessenArndtstrasse 2D-35392 GiessenGermany and Department of MathematicsFaculty of Sciences and MathematicsUniversity of NiViegradska 3318000 NiSerbia and Montenegro Department of mathematics Aligarh Muslim UniversityAligarh 202002India and Department of MathematicsFaculty of Science Department of mathematics Chiang Mai UniversityChiang MaiThailand

Let p = （pk）k=0^∞ be a bounded sequence of positive reals, m C N and u be s sequence of nonzero terms. If x = （xk）k=0^∞ is any sequence of complex numbers we write Δ（m）x for the sequence of the m th order differences of x and Δu^（m）X = {x=（x）k=0^∞ uΔ（m）x ∈ X} for any set X of sequences. We determine the α-, β- and γ-duals of the sets Δμ^（m）X for X=co（p）,c（p）,l∞（p） and characterize some matrix transformations between these spaces Δ^（m）X.

关键词： difference sequences dual spaces matrix transformations

Dynamics of Nonclassicality of Time-and Conductivity-Dependent Squeezed States and Excited Even/Odd Coherent States

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Communications in Theoretical Physics 2017年第4期67卷 365-376页

作者： R.Daneshmand m.K.Tavassoly Atomic and molecular Group Faculty of PhysicsYazd UniversityYazdIran Photonics Research Group Engineering Research CenterYazd UniversityYazdIran The Laboratory of Quantum Information Processing Yazd UniversityYazdIran

Recently, the quantum description of electromagnetic waves in conducting media has been performed. It has been demonstrated that in particular case, the Hamiltonian of the corresponding field can be expressed by Caldirola–Kanai Hamiltonian. In this paper, using the associated annihilation and creation operators of the above-mentioned quantized field, the time-and conductivity-dependent squeezed vacuum and one-photon squeezed states as well as their superpositions, and also the time-and conductivity-dependent excited even and odd coherent states are produced. Also,using a few well-known nonclassicality criteria, the time evolution of nonclassicality features of the above classes of obtained states, in addition to the influence of medium conductivity on them are demonstrated, numerically. It has been shown that the nonclassicality indicators may be adjusted by tuning the conductivity of media.

关键词： Caldirola–Kanai Hamiltonian squeezed vacuum state one-photon squeezed state excited even coherent state excited odd coherent state