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Pressure Drop of Non-Newtonian Liquid Flow Through Elbows

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Chinese Journal of Chemical Engineering 2000年第4期8卷 388-390页

作者： T.k.Banerjee S.k.DAS Chemical Engineering Department University of Calcutta92A.P.C.RoadCalcutta-700 009IndiaChemical Engineering DepartmentUniversity of Calcutta92A.P.C.RoadCalcutta-700 009India

Experimental data on the pressure drop across different types of elbow for non-Newtonian pseudoplastic liquid flow in laminar condition have been presented. A generalized correlation has been developed for predicting ... 详细信息

关键词： non-Newtonian liquid pseudoplastic elbow

Diagenesis,facies and palaeocurrent analysis of Upper Rewa Sandstone around Sagar,Central India

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Journal of Palaeogeography 2023年第4期12卷 546-563页

作者： Gaurav k.Singh Ashish k.Rai Arvind k.Singh Department of Applied Geology Dr.Harisingh Gour VishwavidyalayaSagar 470003Madhya PradeshIndia Geological Survey of India ShillongIndia

The stratigraphic surface represented by a major contact between the Archean Bundelkhand Granite and the extensive Proterozoic Vindhyan sediments is a regional basement cover *** crystalline—sedimentary interface reflects an intense weathering of continental crust during marine *** time-transgressive sand deposition events ***,Rewa and Bhander are mainly witnessed during the entire Vindhyan ***,the Upper Rewa Sandstone comprises one of these events in the Vindhyan *** progress has been made in interpreting these sandstones as a function of entirely marine process to a combination of tidal—fluvio—eolian *** the results have so far been attained on the basis of sedimentary facies,provenance,palaeocurrent analysis,and some of petrography.A distinct differentiation between marine and fluvial components of the Upper Rewa Sandstone still remains ***,we use diagenesis as a parameter for the first time along with facies and palaeocurrent analysis to acquire a clear comprehension of marine-and fluvial-dominated *** present study spans 27 square kilometer area covering 15 stratigraphic sections with a collection of 571directional data from the facies specific sedimentary structures,and 28 samples obtained for the thin section *** lower unit of the Upper Rewa Sandstone shows facies association typical of tidal environment,along with polymodal *** rocks are well sorted and dominantly lithified by authigenic *** development of a complex of syntaxial,passive pore fills,and grain replacive cements reflect normally pressured nature of the lower unit *** upper unit of the Upper Rewa Sandstone however,reveals a facies pattern resembling fluvial processes and unimodal palaeocurrent *** exhibit poor sorting,siliceous,and ferruginous matrix,and development of intense ***,pressure solution is a dominant mode of l

关键词： Palaeocurrent Diagenesis Facies Upper Rewa Sandstone Vindhyan Basin

Oxygen Barrier of Multiwalled Carbon Nanotube/Polymethyl Methacrylate Nanocomposites Prepared by in situ Method

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Journal of Materials Science & Technology 2012年第5期28卷 391-395页

作者： Ajaya k. Pradhan Sarat k. Swain Department of Chemistry North Orissa University Takatpur Baripada 757003 India Department of Chemistry Veer Surendra Sai University of Technology Burla Sambalpur 768018 India

Multiwalled carbon nanotubes （MWCNTs）/poly（methyl methacrylate）（PMMA） nanocomposites were prepared by ultrasonic assisted emulsifier free emulsion polymerization technique with variable concentration of functionalized carbon nanotubes. MWCNTs were functionalized with H 2 SO 4 and HNO 3 with continuing sonication and polished by H 2 O 2 . The appearance of Fourier transform infrared absorption bands in the PMMA/MWCNT nanocomposites showed that the functionalized MWCNT interacted chemically with PMMA macromolecules. The surface morphology of functionalized MWCNT and PMMA/MWCNT nanocomposites were studied by scanning electron microscopy. The dispersion of MWCNT in PMMA matrix was evidenced by high resolution transmission electron microscopy. The oxygen permeability of PMMA/MWCNT nanocomposites gradually decreased with increasing MWCNT concentrations.

关键词： Nanocomposites Morphology Permeability Dispersion

Time-headway distribution for random-sequential-update TASEP with periodic and open boundaries

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第1期7卷 30-41页

作者： Pavel Hrabák Faculty of Information Technology Czech Technical University in PraguePrague 16000Czechia

The temporal-headway distribution for Totally Asymmetric Simple Exclusion Process(TASEP) with random-sequential update is *** the stationary/steady state of the process,exact formula for the step-headway distribution is derived for conditions when the stationary measure is Bernoulli,Le.,for periodic boundaries and for open boundaries with entering boundary rate α and leaving boundary rate 0 satisfying α+β=*** step-headway formula for general values of boundary rates is calculated numerically by means of the matrix product *** formula is applicable mainly for the model defined on finite small lattice representing short segment of complex *** this case the dependency of the motion of individual particles is noticeable and cannot be *** finite lattice results are compared to continuous time distribution obtained by mans of the large L limit It can be observed that the scaled distribution converges quite fast to continuous time ***,in the case of rather small lattice the distribution significantly differs from the limiting ***,in the case of Bernoulli stationary measure,the distribution is not dependent on the position of the reference site on the *** general values of boundary parameters,the shape of the distribution is influenced by the density profile of the process near *** influence vanishes with increasing lattice size.

关键词： Transportation TASEP Time-headway distribution Random-sequential update Periodic and open boundaries

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

On Problems with Downscaling in Internal Flows

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Journal of Thermal Science 2005年第4期14卷 305-307页

作者： Rudolf DVO■k Institute of Thermomechanics Academy of Sciences of the Czech RepublicDolejskova 5Prague 18200 Czech Republic

Problems that may accompany downscaling in internal flows are discussed. Non-dimensional similarity parameters （like Re, M, etc.） depend on parameters that scale down fully （e.g., length）, or that are specified by design （velocities, cascade geometry）, or that are scale invariant （like thermophysical and transport properties of fluids）.This fact has to be taken into acount in the similarity considerations. With decreasing Reynolds number the surface forces become of growing importance, however, if not going down directly to microflows the main problems are connected with the three-dimensional flow structure affecting the skin friction, and with the fact that some of the flow phenomena （e.g. vortical structures） cannot fully develop.

关键词： relatively narrow channels secondary flows skin friction microturbines.

Magnetic and electrical properties of zincblende CrAs

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Chinese Physics B 2008年第6期17卷 2204-2207页

作者：陈鹏 Takamura k SouthWest University Department of Physics Research Institute of Electrical Communication Tohoku University

This paper reports that 9nm zincblende CrAs is grown by molecular-beam epitaxy on InAs buffer layer. The zb-CrAs shows ferromagnetism at room temperature and the total magnetic moment 3.09 ±0.15μB per CrAs unit. The... 详细信息

关键词： zincblende molecular-beam epitaxy half-metal

H.264/SVC Mode Decision Based on Mode Correlation and Desired Mode List

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International Journal of Automation and computing 2014年第5期11卷 510-516页

作者： L.Balaji k.k.Thyagharajan Faculty of Information and Communication Anna University RMD Engineering College

Design of video encoders involves implementation of fast mode decision(FMD) algorithm to reduce computation complexity while maintaining the performance of the coding. Although H.264/scalable video coding(SVC) achieves high scalability and coding efficiency, it also has high complexity in implementing its exhaustive computation. In this paper, a novel algorithm is proposed to reduce the redundant candidate modes by making use of the correlation among layers. A desired mode list is created based on the probability to be the best mode for each block in base layer and a candidate mode selection in the enhancement layer by the correlations of modes among reference frame and current frame. Our algorithm is implemented in joint scalable video model(JSVM)9.19.15 reference software and the performance is evaluated based on the average encoding time, peak signal to noise ration(PSNR)and bit rate. The experimental results show 41.89% improvement in encoding time with minimal loss of 0.02 dB in PSNR and 0.05%increase in bit rate.

关键词： H.264 scalable video coding mode decision mode correlation rate distortion cost

Total and Extractable Manganese and Iron in Some Cultivated Acid Soils of India:Status,Distribution and Relationship with Some Soil Properties

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Pedosphere 2014年第2期24卷 196-208页

作者： S.k.BEHERA A.k.SHUkLA Directorate of Oil Palm Research (DOPR) Indian Institute of Soil Science (IISS)

A total of 400 surface soil （0-15 cm） samples were collected from cultivated soils representing four soil series, namely, Hariharapur, Debatoli, Rajpora and Neeleswaram in Orissa, Jharkhand, Himachal Pradesh and kerala states of India, respectively, and were analyzed to measure the contents of total and extractable Mn and Fe, to establish the relationship among total and extractable Mn and Fe and soil properties, and to characterize the spatial distribution pattern of Mn and Fe in some cultivated acid soils of India. The contents of total as well as extractable Mn and Fe varied widely with extractants and soil series. However, the amounts of Mn or Fe extracted by diethylene triamine penta-acetic acid （DTPA）, Mehlich 1, Mehlich 3, 0.1 mol L-1 HC1 and ammonium bicarbonate DTPA （ABDTPA） were significantly correlated with each other （P 〈 0.01）. Based on the DTPA-extractable contents and the critical limits （2 mg Mn kg-1 soil and 4.5 mg Fe kg-1 soil） published in the literature, Mn and Fe deficiencies were observed in 7% 23% and 1%-3% of the soil samples, respectively. The content of soil organic carbon （SOC） had greater influence on total and DTPA-extractable Fe than did soil pH. Geostatistical analysis revealed that total and DTPA-extractable Mn and Fe contents in the acid soils were influenced by soil pH, SOC content, and exchangeable cations like potassium, calcium and magnesium. Spatial distribution maps of total and DTPA-extractable Mn and Fe in soil indicated different distribution patterns.

关键词： micronutrients extractant geostatistical analysis spatial variability