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STUDY OF AXIAL VELOCITY IN GAS CYCLONES BY 2D-PIV,3D-PIV,AND SIMULATION

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China Particuology 2006年第3期4卷 204-210页

作者： Zhengliang Liu Jinyu Jiao Ying Zheng Department of Chemical Engineering University of New Brunswick 15 Dineen Drive P.O. Box 4400 Fredericton NB Canada E3B 5A3 Canada

The axial velocity distribution in a gas cyclone has been examined with two-dimensional particle image velocimetry （2D-PIV） and three-dimensional particle image velocimetry （3D-PIV） experiments in this study. Due to the limitation of 2D-PIV configuration, the contamination generated by the strong tangential velocity in the cyclone can be registered in the axial velocity detected by 2D-PIV. Efficient methods are proposed in this work to remove this contamination. The contamination-removed 2D-PIV data agree well with 3D-PIV results. The distributions of the axial velocity are also computed by the Reynolds stress model （RSM） and verified using the PIV experimental results. Reasonable agreements are obtained.

关键词： particle image velocimetry (PIV) numerical simulation axial velocity cyclone separators

Applicability of discrete element method with spherical and clumped particles for constitutive study of granular materials

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 240-251页

作者： Tongming Qu Min Wang Yuntian Feng Zienkiewicz Centre for Computational Engineering College of EngineeringSwansea UniversitySwanseaWales SA18EPUK T-3 Fluid Dynamics and Solid Mechanics Group Theoretical DivisionLos Alamos National LaboratoryLos AlamosNM87545USA

Discrete element method(DEM)has been intensively used to study the constitutive behaviour of granular ***,to what extent a real granular material can be reproduced by virtual DEM simulations remains *** study attempts to answer this question by comparing DEM simulations with typical features of experimental granular *** groups of models with spherical and clumped particles are investigated from four perspectives:(i)deviatoric stress and volumetric behaviour;(ii)critical state behaviour;(iii)stress-dilatancy relationship;and(iv)the evolution of principal stress ratio against axial *** results demonstrate that DEM with spherical or clumped particles is capable of qualitatively describing macroscopic deviatoric stress responses,volumetric behaviour,and critical state behaviour observed in experiments for granular *** the other hand,some qualitative deviations between experiments and the investigated DEM simulations are also observed,in terms of the stress-dilatancy behaviour and principal stress ratio against axial strain,which are proven to be critical for constitutive *** results demonstrate that DEM with spherical or clumped particles may not necessarily fully capture experimental features of granular materials even from a qualitative *** is thus encouraged to thoroughly validate DEM with experiments when developing constitutive models based on DEM observations.

关键词： Discrete element method(DEM) Granular materials Constitutive behaviour Deviatoric hardening model Rolling resistance model Irregular particles

NMR chemical shifts of carbon atoms and characteristic shift ranges in the oil sample

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Petroleum Research 2022年第2期7卷 269-274页

作者： Ilfat Z.Rakhmatullin Sergej V.Efimov Alexander V.Klochkov Oleg I.Gnezdilov Mikhail A.Varfolomeev Vladimir V.Klochkov Kazan Federal University 18 Kremlevskaya St.Kazan420008Russian Federation

Application of high resolution^(13)C nuclear magnetic resonance(NMR)spectroscopy to characterize crude oil was *** chemical shifts of^(13)C NMR functional groups that determine the composition of the oil sample were *** fractions of primary,secondary,quaternary,tertiary,aromatic groups,aromatic factor and average hydrocarbon chain length of aliphatic hydrocarbons of the oil sample according to^(13)C NMR spectra were *** description of the^(13)C NMR spectra of the oil sample using a single consideration of three NMR spectra:^(13)C,^(13)C Attached Proton Test(APT),^(13)C with Gated Decoupling(GD)was *** different contribution of the studied oil sample in the aliphatic(10e75 ppm)and aromatic(115e165 ppm)areas of the^(13)C NMR spectra was *** presence of all major hydrocarbon components in the studied oil sample was established on the quantitative level,the aromaticity factor and the mean length of the hydrocarbon chain were *** fractions of aromatic molecules and functional groups constituting oil hydrocarbons were *** this work we demonstrate that the attached proton test and gated decoupling^(13)C NMR spectroscopy can afford all information to complete the chemical shift assignment of an oil sample,especially for determination of long range 1He^(13)C coupling constants and^(13)C multiplicity.

关键词： ^(13)C NMR spectroscopy Crude oil Oil fraction Functional group Qualitative analysis Quantitative composition Aromaticity Attached proton test Gated decoupling

Perturbative Correction to Transverse Ward-Takahashi Relation for the Vector Vertex

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Communications in Theoretical Physics 2003年第5期39卷 559-560页

作者： HEHan-Xin YUHong-Wei ChinaInstituteofAtomicEnergy P.O.Box275(18)Beijing102413China InstituteofTheoreticaPhysics AcademiaSinicaBeijing100080China ChinaInstituteofAtomicEnergy P.O.Box275(18)Beijing102413China

We re-derive exactly the transverse Ward–Takahashi relation for the vector vertex in momentum space. The result shows that this transverse Ward–Takahashi relation in momentum space involves a perturbative correction term. We demonstrate explicitly that this transverse Ward–Takahashi relation is satisfied indeed at one-loop order.

关键词： Ward-Takahashi relations perturbative correction

Liver fibrosis markers in alcoholic liver disease

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World Journal of Gastroenterology 2014年第25期20卷 8018-8023页

作者： Lech Chrostek Anatol Panasiuk Department of Biochemical Diagnostics Medical University of Bialystok 15-540 Bialystok Poland Department of Infectious Diseases and Hepatology Medical University of Bialystok 15-540 BialystokPoland

Alcohol is one of the main factors of liver damage. The evaluation of the degree of liver fibrosis is of great value for therapeutic decision making in patients with alcoholic liver disease(ALD). Staging of liver fibrosis is essential to define prognosis and management of the disease. Liver biopsy is a gold standard as it has high sensitivity and specificity in fibrosis diagnostics. Taking into account the limitations of liver biopsy, there is an exigency to introduce non-invasive serum markers for fibrosis that would be able to replace liver biopsy. Ideal serum markers should be specific for the liver, easy to perform and independent to inflammation and fibrosis in other organs. Serum markers of hepatic fibrosis are divided into direct and indirect. Indirect markers reflect alterations in hepatic function, direct markers reflect extracellular matrix turnover. These markers should correlate with dynamic changes in fibrogenesis and fibrosis resolution. The assessment of the degree of liver fibrosis in alcoholic liver disease has diagnostic and prognostic implications, therefore noninvasive assessment of fibrosis remains important. There are only a few studies evaluating the diagnostic and prognostic values of noninvasive biomarkers of fibrosis in patients with ALD. Several noninvasive laboratory tests have beenused to assess liver fibrosis in patients with alcoholic liver disease, including the hyaluronic acid, FibroTest, FibrometerA, Hepascore, Forns and APRI indexes, FIB4, an algorithm combining Prothrombin index(PI), α-2 macroglobulin and hyaluronic acid. Among these tests, Fibrotest, FibrometerA and Hepascore demonstrated excellent diagnostic accuracy in identifying advanced fibrosis and cirrhosis, and additionally, Fibrotest was independently associated with survival. Therefore, the use of biomarkers may reduce the need for liver biopsy and permit an earlier treatment of alcoholic patients.

关键词： Liver fibrosis markers Alcoholic liver disease

Amplitude Factorization Method in the Atmospheric Gravity-Wave Equation

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Communications in Computational Physics 2007年第5期2卷 993-1006页

作者： Rein Room Marko Zirk Institute of Environmental Physics Tartu UniversityUlikooli 18Tartu 50090Estonia.

A novel amplitude factorization method is applied to solve a discrete buoyancy wave equation with arbitrary wind and temperature height *** solution is given in the form of a cumulative product of complex factors,which are computed by a nonlinear,inhomogeneous,two-member recurrence formula,initiated from a radiative condition on *** of the wave equation due to evanescent winds are eliminated by turbulent *** method provides an estimation of the minimal vertical resolution,required to attain a stable accurate *** areas of application of the developed numerical scheme are high resolution modelling of orographic waves for arbitrary orography in general atmospheric stratification conditions,and testing of adiabatic kernels of numerical weather prediction models.

关键词： Atmospheric gravity waves linear buoyancy wave equation arbitrary stratification numerical solution amplitude factorization method.

The History of Disaster Incidents and Impacts in Nepal 1900–2005

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International Journal of Disaster Risk Science 2012年第3期3卷 147-154页

作者： Komal Raj Aryal Disaster and Development Centre Northumbria UniversityNewcastle NE18STUK

The people of Nepal today are exposed to perennial local disaster events and profound vulnerability to disaster. The combined efforts of government, donors, UN agencies, NGOs, and Nepalese communities are needed to avert the impacts of disaster events. Much more can be done immediately to reduce the impacts by reviewing the scope and distribution of past disaster events. This article provides an overview of Nepal’s disaster vulnerability through an analysis of the record of disaster events that occurred from 1900 to 2005. The data were generated from historical archives and divided into incidents at the district, subnational, and national levels. Statistical and Geographical Information System(GIS) analyses were carried out to generate district level disaster vulnerability maps. It is concluded that small-scale, local disasters have a greater cumulative impact in terms of casualties than large-scale, national disasters.

关键词： disaster district History

Corrupted Infrastructure： Imperialism and Environmental Sovereignty in Shanghai, 1873-1911

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Frontiers of History in China 2015年第3期10卷 428-456页

作者： Shirley Ye Depa15maent of History University of Birmingham Edgbaston B 15 2TT UK

The introduction of Western science in order to change physical and operational aspects of Shanghai＇s Huangpu River had been debated by Qing and Western officials since almost the beginning of its history as a Treaty Port. At stake in those debates was the perception of the river＇s proper use： as a natural barrier for military defense, or as a conduit for global trade. After the Western powers unified to militarily suppress the Boxer Uprising in 1900, they attained their long-awaited goal of the right to transform the river for global trade as part of Article 11 of the Boxer Protocol： the Junpuju （or Huangpu Conservancy Board） was created and authorized by the central government to make the Huangpu River navigable for shipping vessels. Although the Junpuju continued the ethos of earlier extra-bureaucratic organizations established during the Self-Strengthening Movement, after 1901 the organization bore the authority of the central government. During the era of the New Policies, Qing officials were intent on revising the original terms of river conservancy so that they would be more favorable to Chinese sovereignty. At the same time, imperialist rivalries among the Western powers ruptured the apparent unity of the earlier alliance during the suppression of the Boxer Uprising. Before long, Western corruption in the Huangpu River dredging was brought to the attention of Qing officials, who deftly used it to recover Qing control over certain parts of the body of the river.

关键词： Boxer Protocol corruption infrastructure Gu Hongming Huangpu River new policies Self-Strengthening Sino-French War

Hybrid image of three contents

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Visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 31-38页

作者： Peeraya Sripian Yasushi Yamaguchi SIT Research Laboratory Shibaura Institute of TechnologyRoom#04R313-7-5 ToyosuKoto-kuTokyo 135-8548Japan The University of Tokyo Bldg.#15Room#505A3-8-1KomabaMeguro-kuTokyo 153-8902Japan

A hybrid image allows multiple image interpretations to be modulated by the viewing ***,it can be constructed by combining the low and high spatial frequencies of two different *** original hybrid image synthesis was limited to similar shapes of source images that were aligned in the edges,e.g.,faces with a different expression,to produce an effective double image *** our previous work,we proposed a noiseinserted method for synthesizing a hybrid image from dissimilar shape images or unaligned *** this work,we propose a novel method for adding an image to be seen from a middle viewing *** middlefrequency(MF)image is extracted by a special bandpass filter,which generates ringing while extracting only specified frequency *** this method,the middle frequency should be perceived as a meaningless pattern when viewed from a far distance and close up.A parameter tuning experiment was performed to determine the suitable cutoff frequencies for designing the filter for the MF *** found that ringings of a suitable size could be used to make the middle frequency less noticeable when seen from far away.

关键词： Hybrid image Contrast sensitivity Frequency filtering Scale-space