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Generalized Fourier Transform Method for Solving Nonlinear Anomalous Diffusion Equations

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Applied Mathematics 2019年第12期10卷 1039-1047页

作者： j.e Yao Cameron L. Williams Fazle Hussain donald j. kouri Department of Mechanical Engineering Texas Tech University Lubbock TX USA Department of Mathematics University of Houston Houston TX USA Departments of Mechanical Engineering and Physics University of Houston Houston TX USA

The solution of a nonlinear diffusion equation is numerically investigated using the generalized Fourier transform method. This equation includes fractal dimensions and power-law dependence on the radial variable and on the diffusion function. The generalized Fourier transform approach is the extension of the Fourier transform method used for the normal diffusion equation. The feasibility of the approach is validated by comparing the numerical result with the exact solution for a point-source. The merit of the numerical method is that it provides a way to calculate anomalous diffusion with an arbitrary initial condition.

关键词： Generalized Fourier Transform Anomalous Diffusion Nonlinear

Effect of particle stress tensor in simulations of dense gas-particle flows in fluidized beds

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Particuology 2018年第3期16卷 31-43页

作者： Mohammad Reza Haghgoo donald j. Bergstrom Raymond j. Spiteri Department of Mechanical Engineering University of Saskatchewan Saskatoon SK SFN 5A9 Canada Department of Computer Science University of Saskatchewan Saskatoon. SK S7N 5C9 Canada

A two-fluid model based on the kinetic theory of granular flow for the rapid-flow regime and the Coulomb friction law for the quasi-static regime is applied to predict the hydrodynamics of dense gas-particle flow in a three-dimensional fluidized bed. Two different models for the particle stress tensor that use different constitutive equations in the elastic-inertial regime are examined to assess their ability to predict bed dynamics. To understand how particle stress models affect structural features of the flow, a quantitative analysis is performed on some important aspects of the mechanics of bubbling beds that have received relatively little attention in the literature. Accordingly, different flow regimes are identified in the context of fluidized beds through the dimensionless inertial number, and the main characteristics of each regime are discussed. In addition, how the particle stress tensor manifests itself in the bubble characteristics, natural frequency of the bed, and particle Reynolds stress are investigated, all of which help to better understand the complex dynamics of the fluidized bed. The numerical results are validated against pub- lished experimental data and demonstrate the significant role of the stress tensor in the elastic-inertial regime.

关键词： Two-fluid model Inertial number Fluidized bed Flow regime Particle Reynolds stress MFIX

Management information systems for the information age /Stephen Haag, Maeve Cummings, donald j. McCubbrey. 5th ed.

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Bioacoustic variation of swimbladder disturbance sounds in Neotropical doradoid catfishes （Siluriformes： Doradidae, Auchenipteridae）： Potential morphological correlates

2005年

作者： Stephen Haag donald j. McCubbrey. Maeve Cummings

Includes bibliographical references and index.

ISBN: (数字)0072935863

ISBN: (纸本)0071107770;0072935863

Includes bibliographical references and index.

关键词： Information technology.

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Current Zoology 2012年第1期58卷 171-188页

作者： Kaatz, Ingrid M. Stewart, donald j. Department of Environmental and Forest Biology SUNY College of Environmental Science and Forestry Syracuse NY 13210 USA

Swimbladder disturbance sounds of doradoid catfishes （Doradidae and Aucheniptefidae） demonstrated striking waveform and spectrographic variation. We surveyed sounds of 25 doradoid species in 20 genera comparing these to sounds of four vocal outgroup catfish families. Sounds were either continuous waveforms （lacking interpulses） or pulsed （groups of pulses repeated at fixed temporal intervals）. This is the first evidence for swimbladder calls with fixed interpulse patterns in catfishes. Vocal mechanism components that were similar between doradids and auchenipterids included： swimbladder shape, swimbladder dimensions and sonic muscle-somatic index. Morphological traits that showed variation among taxa and were evaluated for po- tential correlates of call diversity are： 1） diverticula （marginal outpocketings of the swimbladder with no connection to inner ear） and 2） elastic spring apparatus Mtillerian rami （ESA-Mr）. Within the doradid subfamilies and within the Auchenipteridae most species differed significantly in dominant frequency with frequency ranges overlapping to some extent for most. Doradid swim- bladder diverticula did not explain dominant frequency variation within the doradoid superfamily. Some doradids with conical ESA-Mr had the highest dominant frequency sounds. Auchenipterids included both relatively lower and higher dominant fre- quency sound producers but lacked diverticula and had discoidal ESA-Mr. Comparing a phylogeny of doradoid genera with out- group taxa, we infer that complex diverticula and conical ESA-Mr are derived characters within the Doradidae. Species repre- senting outgroup families produced either continuous lower dominant frequency sounds （aspredinids, mochokids and pseudopimelodids） or pulsed higher dominant frequency sounds （pimelodids） [Current Zoology 58 （1）： 171-188, 2012].

关键词： Catfishes Communication Signal evolution Vocal mechanisms

Characterization of Kiwifruit Xyloglucan

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j.urnal of Integrative Plant Biology 2009年第10期51卷 933-941页

作者： Xingj.n Li Naoki Sakurai donald j. Nevins Academy of the State Administration of Grains Beijing 100037 China Graduate School of Biosphere Science Hiroshima University Kagamiyama 1-7-1 Higashi-hiroshima 739-8521 Japan Department of Plant Sciences University of California Davis CA 95616 USA

Structural characteristics of xyloglucan are constant in the pericarp cell walls of kiwifruit （Actinidia deliciosa） throughout fruit enlargement and maturation. Most of the xyioglucan （XG） persists in the cell walls of ripe kiwifruit. XG from the pericarp tissues of 36-h ethylene-treated kiwifruit was extracted as hemicellulose Ⅱ （HC-Ⅱ） with 4.28 M KOH containing 0.02% NaBH4, and purified using iodine precipitation and subsequent anion-exchange chromatography. This purifying protocol increased XG purity from 50 mol% in HC-Ⅱ fraction to 62 mol% in the purified XG powder. The molar ratio of glucose： xylose： galactose： fucose in the purified XG was 10： 6.9： 2.1： 0.3. Gel permeation chromatography indicated that purified XG had an average molecular-mass of 161 KDa, a value that exceeds the 95 KDa Mr determined for total polymeric sugars. Sugar linkage analysis confirmed the lack of fucose in the kiwifruit XG, but a small amount of arabinoxylan and low Mr glucomannan remained associated with this fraction.

关键词： Actinidia deliciosa cell walls glucomannan hemicellulose sugar linkage analysis xyloglucan

Characterization of Binding Sites of Eukaryotic Transcription Factors

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Genomics, Proteomics & Bioinformatics 2006年第2期4卷 67-79页

作者： j.ang Qian j.mmy Lin donald j. Zack The Wilmer Institute Department of Molecular Biology and Genetics Department of Neuroscience McKusick-Nathans Institute of Genetic Medicine Johns Hopkins University School of Medicine Baltimore MD 21287 USA.

To explore the nature of eukaryotic transcription factor （TF） binding sites and determine how they differ from surrounding DNA sequences, we examined four features associated with DNA binding sites： G＋C content, pattern complexity, palindromic structure, and Markov sequence ordering. Our analysis of the regulatory motifs obtained from the TRANSFAC databases using yeast intergenic sequences as background, revealed that these four features show variable enrichment in motif sequences. For example, motif sequences were more likely to have palindromic structure than were background sequences. In addition, these features were tightly localized to the regulatory motifs, indicating that they are a property of the motif sequences themselves and are not shared by the general promoter ＂environment＂ in which the regulatory motifs reside. By breaking down the motif sequences according to the TF classes to which they bind, more specific associations were identified. Finally, we found that some correlations, such as G＋C content enrichment, were species-specific, while others, such as complexity enrichment, were universal across the species examined. The quantitative analysis provided here should increase our understanding of protein-DNA interactions and also help facilitate the discovery of regulatory motifs through bioinformatics.

关键词： transcription factor promoter gene regulation bioinformatics

A SURVEY OF THE HOLARCTIC LINYPHIIDAE (ARANEAE),A REVIEW OF THE ERIGONINE GENUS ZORNELLA j.CKSON, 1932

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动物分类学报 2007年第1期32卷 21-34页

作者： Yuri M. Marusik donald j. Buckle Seppo Koponen Institute for Biological Problems of the North Portovaya Str. 18 Magadan 685000 Russia 620 Albert Avenue Saskatoon Saskatchewan S7N 1G7 Canada Zoological Museum University of Turku FI-20014 Turku Finland

The Holarctic erigonid genus Zornella has been surveyed. Four species are recognized in this genus, two Palaearctic: ***(***,11879) & *** ***., and two Nearctic: ***(Banks, 1906) & *** Chamberlin,*** is demonstrated that neither nearctic species is conspecific with *** as was thought by Holm and other authors. *** ***. is described from northeastern Siberia. All of the species are illustrated and their distributions mapped.

关键词： Spiders Araneae Erigoninae Holarctic Zornella new species redescription

Accounting principles / j.rry j. Weygandt, donald E. Kieso, Paul D. Kimmel. 6th ed.

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Time Scale of Partial Melting of KLB-1 Peridotite: Constrained from Experimental Observation and Thermodynamic Models

2002年

作者： j.rry j. Weygandt donald E. Kieso Paul D. Kimmel.

Includes indexes.

ISBN: (数字)0471382280

ISBN: (纸本)0471382280

Includes indexes.

关键词： Accounting.

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j.urnal of Earth Science 2018年第2期29卷 245-254页

作者： Wei Du Li Li donald j.Weidner State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Mineral Physics Institute Department of Geosciences University of New York at Stony Brook

Partial melting experiments were carried on KLB-1 peridotite, a xenolith sample from the Earth＇s upper mantle, at 1.5 GPa and temperatures from 1 300 to 1 600 ℃, with heating time varies from 1 to 30 min. We quantify the axial temperature gradient in the deformation-DIA appa- ratus （D-DIA） and constrain the time scale of partial melting by comparing experimental observa- tions with calculated result from pMELTS program. The compositions of the liquid phase and the coexisting solid phases （clinopyroxene, orthopyroxene, and olivine） agree well with those calculated from pMELTS program, suggesting that local chemical equilibrium achieves during partial melting, although longer heating time is required to homogenize the bulk sample. The Mg# （=Mg/（Mg＋Fe） moi.%） of olivines from the 1-minute heating experiment changed continuously along the axial of the graphite capsule. A thermal gradient of 50 ℃/mm was calculated by comparing the Mg# of oli- vine grains with the output of pMELTS program. Olivine grains at the hot end of the graphite cap- sule from the three experiments heated at 1 400 ℃ but with different annealing time show consis- tence on Mg#, indicating that partitioning of Fe2＋ between the olivine grains and the silicate melt happened fast, and partial melting occurs in seconds.

关键词： peridotite partial melting temperature gradient pMELTS program.