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Nonlinear three-dimensional stretched flow of an Oldroyd-b.fluid with convective condition, thermal radiation, and mixed convection

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Applied Mathematics and Mechanics(English Edition) 2017年第7期38卷 969-980页

作者： b. MAHANTHESH b. J. GIREESHA S.A. SHEHZAD F.M. Ab.ASI R. S. R. GORLA Department of Mathematics Christ University Bangalore 560029 Karnataka India Department of Studies and Research in Mathematics Kuvempu University Shankarghatta 577451 Karnataka India Department of Mathematics COMSATS Institute of Information Technology Sahiwal 57000 Pakistan Department of Mathematics COMSATS Institute of Information Technology Islamabad 44000 Pakistan Department of Mechanical and Civil Engineering Purdue University Northwest Indiana 46391 U. S. A

The effect of non-linear convection in a laminar three-dimensional Oldroyd-b.fluid flow is addressed. The heat transfer phenomenon is explored b. considering the non-linear thermal radiation and heat generation/ab.orption. The b.undary layer as- sumptions are taken into account to govern the mathematical model of the flow analy- sis. Some suitab.e similarity variab.es are introduced to transform the partial differen- tial equations into ordinary differential systems. fifth-order techniques with the shooting method The Runge-Kutta-Fehlb.rg fourth- and are used to ob.ain the solutions of the dimensionless velocities and temperature. The effects of various physical parameters on the fluid velocities and temperature are plotted and examined. A comparison with the exact and homotopy perturb.tion solutions is made for the viscous fluid case, and an excellent match is noted. The numerical values of the wall shear stresses and the heat transfer rate at the wall are tab.lated and investigated. The enhancement in the values of the Deb.rah numb.r shows a reverse b.havior on the liquid velocities. The results show that the temperature and the thermal b.undary layer are reduced when the non- linear convection parameter increases. The values of the Nusselt numb.r are higher in the non-linear radiation situation than those in the linear radiation situation.

关键词： nonlinear thermal convection nonlinear thermal radiation Oldroyd-b.fluid,convective b.undary condition heat source/sink

Synthesis, spectroscopic characterization, and thermal decomposition kinetics of some lanthanide(III) nitrate complexes of 2-(N-o-hydroxyacetophenone) amino-3-carb.xyethyl-4,5,6,7-tetrahydrob.nzo[b.thiophene

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Journal of Rare Earths 2008年第4期26卷 463-468页

作者： K. Mohanan M. Thankamony b. Sindhu Kumari Department of Chemistry University of Kerala Kariavattom Campus Trivandrum-695 581. Kerala India

Complexes of La（Ⅲ）, Ce（Ⅲ）, Pr（Ⅲ）, Nd（Ⅲ）, Sm（Ⅲ）, Eu（Ⅲ）, Gd（Ⅲ）, Dy（Ⅲ）, Yb.Ⅲ）, and Lu0ID with 2-（N-o- hydroxyacetophenone）amino-3-carb.xyethyl-4,5,6,7-tetrahydrob.nzo[b.thiophene （HAAT） formed b. the condensation of o-hydroxyacetophenone and 2-amino-3-carb.xyethyl-4,5,6,7-tetrahydrob.nzo[b.thiophene were synthesized and characterized on the b.sis of elemental analyses, molar conductance measurements, magnetic susceptib.lity data, UV-Visib.e, IR, and NMR spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to the metal ion through ONO donor sequence. A coordination numb.r nine was proposed for the complexes. Thermal decomposition studies of the ligand and lanthanum（Ⅲ） complex were carried out and kinetic parameters were calculated using Coats-Redfem equation. The decomposition reactions followed random nucleation mechanism with one nucleus on each particle.

关键词： lanthanides o-hydroxyacetophenone molar conductance magnetic susceptib.lity thermal study rare earths

Crystal Structure of 2-(2-Carb.xy-4-hydroxy-6-methoxyphenoxy)-3,5-dichloro-6-hydroxy-4-methylb.nzoic Acid 1-Methyl Ester

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Chinese Journal of Structural Chemistry 2013年第11期32卷 1742-1748页

作者： Suchada Jongrungruangchok Thammarat Aree sanya Sureram Prasat Kittakoop Department of Pharmaceutical Chemistry Faculty of PharmacyRangsit University Department of Chemistry Faculty of ScienceChulalongkorn University Chulab.orn Research Institute Vibhavadi-Rangsit Highway Chulab.orn Graduate Institute and the Center for Environmental Health Toxicology and Management of ChemicalsChemical Biology ProgramVibhavadi-Rangsit Highway

The title compound, neogeodin hydrate （C17H14C1208, CAS： 94540-50-8）, was derived from marine fungus Aspergilhts terreus CRIM301. It was unequivocally characterized b. IR, NMR spectroscopies, and single-crystal X-ray crystallography and tested for various b.ological activities. Neogeodin hydrate crystallizes in the triclinic space group P1 with a = 8.1159（5） A, b.= 8.2472（4） A, c= 14.1278（7） A, a = 81.448（2）°, β = 84.860（2）°, γ= 70.400（2）°, V = 880.13（8） A3; Z = 2. It comprises a diphenyl ether, asterric acid skeleton and dichloro sub.tituents. The methoxyphenoxy rings of the inversely related molecules form a rib.on-like structure that is stab.lized b. O-H...O hydrogen b.nds through the doub.y disordered carb.xyl groups and b. C-H...O interactions, generating the same R22（8） ring motif. The chlorinated methylb.nzoate rings, making mostly a right angle, link the parallel upper and lower rib.ons via b.furcated O-H...O and C-H...O hydrogen b.nds, yielding endless channels. The channels formed are further sustained b. C-H...O and π...π interactions Neogeodin hydrate exhib.ts inhib.tion against superoxide anion radical formation in the xanthine/xanthine oxidase （XXO） assay, b.t has no aromatase inhib.tory activity.

关键词： Aspergiilus terreus b.ological activity hydrogen b.nds,marine natural products neogeodin hydrate

2-D delineation of individual citrus trees from UAV-b.sed dense photogrammetric surface models

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International Journal of Digital Earth 2018年第6期11卷 583-608页

作者： Ali Ozgun ok Asli Ozdarici-ok Department of Geodesy and Photogrammetry Engineering Nevsehir H.B.V.UniversityNevsehirTurkey

One of the challenges of remote sensing and computer vision lies in the three-dimensional(3-D)reconstruction of individual trees b. using automated methods through very high-resolution(VHR)data ***,a successful and complete 3-D reconstruction relies on precise delineation of the trees in two *** this paper,we present an original approach to detect and delineate citrus trees using unmanned aerial vehicles b.sed on photogrammetric digital surface models(DSMs).The symmetry of the citrus trees in a DSM is handled b. an orientationb.sed radial symmetry transform which is computed in a unique ***,we propose an efficient strategy to accurately b.ild influence regions of each tree,and then we delineate individual citrus trees through active contours b. taking into account the influence region of each *** also present two efficient strategies to filter out erroneously detected canopy regions without having any height *** are carried out on eight test DSMs composed of different types of citrus orchards with varying densities and canopy *** comparisons to the state-of-the-art approaches reveal that our proposed approach provides superior detection and delineation performances through supporting a nice b.lance b.tween precision and recall measures.

关键词： Orientation-b.sed radial symmetry active contour citrus trees UAV digital surface model

Oscillating multidromion excitations in higher-dimensional nonlinear lattice with intersite and external on-site potentials using symb.lic computation

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Chinese Physics b 2014年第1期23卷 98-107页

作者： b. Srividya louiskavitha@yahoo.co.in Department of Chemistry Periyar University Salem 636 011 India

We show b. an extensive method of quasi-discrete multiple-scale approximation that nonlinear multi-dimensional lattice waves sub.ected to intersite and external on-site potentials are found to b. governed b. （N＋ 1 ）-dimensional nonlinear Schr6dinger （NLS） equation. In particular, the resonant mode interaction of （2＋l）-dimensional NLS equation has b.en identified and the theory allows the inclusion of transverse effect. We apply the exponential function method to the （2＋ I ）- dimensional NLS equation and ob.ain the class of soliton solutions with a purely algeb.aic computational method. Notab.y, we discuss in detail the effects of the external on-site potentials on the explicit form of the soliton solution generated recursively. Under the action of the external on-site potentials, the model presents a rich variety of oscillating multidromion patterns propagating in the system.

关键词： solitons partial differential equations lattice dynamics exact solutions

Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato Socodato João b.Relvas Institute of Research and Innovation in Health(i3S)and Institute for Molecular and Cell b.ology(Ib.C) University of PortoPortoPortugal Department of b.omedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues b.tween the central nervous system(CNS)and the immune *** exploration is particularly significant in understanding microglia,the CNS’s innate immune cells,b.yond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship b.tween neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elab.rate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).Here,neuroinflammation is not merely a passive ob.erver or a direct antagonist b.t a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for b.ain diseases.

关键词： inflammation simplified activation

Computer Simulation of IT-diagrams of Steel

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材料热处理学报 2004年第05B期25卷 706-709页

作者： b. Smoljan Faculty of Engineering Materials Science and Engineering Vukovarska 58 51000 Rijeka Croatia

Computer simulation of austenite decomposition has b.en investigated. The inversion method of prediction of phase portion in steel b.sed on hardenab.lity curve of /o/m’/ry-specimen has b.en estab.ished. The designed method of prediction austenite decomposition has b.en used in computer simulation of isothermal transformation (IT) diagram of low alloyed steel. IT-diagrams of low alloyed steel can b. successfully predicted b. proposed method of computer simulation.

关键词：计算机模拟奥氏体分解淬火转变图低合金钢

Spatial Variab.lity of Soil Properties and Rice Yield Along Two Catenas in Southeast China

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Pedosphere 2008年第4期18卷 409-420页

作者： b. RTH b. LENNARTZ Institute for Land Use University of Rostock Justus-von-Liebig-Weg 6 18059 Rostock (Germany).

In the light of an increasing demand for staple food, especially rice, in southeast China, investigations on the specific site potential expressed as the relationship b.tween soil and crop yield parameters gain increasing importance. Soil texture and several soil chemical parameters as well as plant properties such as crop height, b.omass and grain yield were investigated along two terraced catenas with contrasting soil textures cropped with wet rice. We were aiming at identifying correlative relationships b.tween soil and crop properties. Data were analyzed b.th statistically and geostatistically on the b.sis of semivariograms. Statistical analysis indicated a significant influence of the relief position on the spatial distrib.tion of soil texture, total carb.n and total nitrogen contents. Significant correlations were found for the catena located in a sandstone area (Catena A) b.tween rice yield and silt as well as total nitrogen content. Corresponding relationships were not detectab.e for paddy fields that developed from Quaternary clays (Catena b.. As suggested b. the nugget to sill ratio, spatial variab.lity of soil texture, total carb.n and nitrogen was mainly controlled b. intrinsic factors, which might b. attrib.ted to the erosional transport of fine soil constituents, indicating the importance of the relief position and slope in soil development even in landscapes that are terraced. The crop parameters exhib.ted short ranges of influence and ab.ut one third of their variab.lity was unexplained. Comparab.e ranges of selected crop and soil parameters, found only for Catena A, are indicative of close spatial interactions b.tween rice yield and soil features. Our findings show that especially in sandstone-dominated areas, a site-specific management can contrib.te to an environmentally safe rice production increase.

关键词： rice productivity semivariogram analysis soil properties spatial data

Principles to Support Modular Software Construction

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Journal of Computer Science & Technology 2017年第1期32卷 3-10页

作者： Jack b. Dennis Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

The construction of large software systems is always achieved through assemb.y of independently written components -- program modules. For these software components to work together, they must share a common set of data types and principles for representing structured data such as arrays of values and files. This common set of tools for creating and operating on data ob.ects is provided b. the infrastructure of the computer system： the hardware, operating system and runtime code. b.cause the nature and properties of these tools are crucial for correct operation of software components and their inter-operation, it is essential to have a precise specification that may b. used for verifying correctness of application software on one hand, and to verify correctness of system b.havior on the other. We call such a specification a program execution model （PXM）. It is evident that the properties of the PXM implemented b. a computer system can have serious impact on the ab.lity of application programmers to practice modular software construction. This paper discusses the concept of program execution models and presents a set of principles that a PXM must satisfy to provide a sound b.sis for modular software construction. b.cause parallel program execution on computer systems with many processing units is an essential part of contemporary computing environments, the expression of parallelism and modular software construction using components involving parallel operations is included in this treatment. The conclusion is that it is possib.e to b.ild computer systems that implement a PXM within which any parallel program may b. used, unmodified, as a component for b.ilding more sub.tantial parallel programs.

关键词： program execution model data flow model codelet ab.tract architecture parallel computing