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Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 16-25页

作者： LU Lin1,2,TENG Bin3,ChENG Liang 4,SUN Liang5 & ChEN XiaoBo6 1 Center for Deepwater Engineering,Dalian university of Technology,Dalian 116024,China 2 State key Laboratory of Structural Analysis for Industrial Equipment,Dalian university of Technology,Dalian 116024,China 3 State key Laboratory of Coastal and Offshore Engineering,Dalian university of Technology,Dalian 116024,China 4 School of Civil and Resource Engineering,The university of Western Australia,Crawly 6003,Australia 5 Centre for Offshore Research and Engineering,department of Civil Engineering,National university of Singapore,117576,Singapore 6 Research department,Bureau Veritas,Neuilly-Sur-Seine,92570,France Center for Deepwater Engineering Dalian University of Technology Dalian China State key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian China State key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian China School of Civil and Resource Engineering The University of Western Australia Crawly Australia Centre for Offshore Research and Engineering Department of Civil Engineering National University of Singapore Singapore Singapore Research department Bureau Veritas Neuilly-Sur-Seine France

Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water *** numerical results are compared with experimental data available in the *** comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the resonant frequency reasonably *** the conventional potential flow model(without artificial damping term) significantly over-predicts the wave height in narrow gaps around the resonant *** order to calibrate the appropriate damping coefficient used for the potential model and make it work as well as the viscous fluid model in predicting the resonant wave height in narrow gaps but with little computational efforts,the dependence of damping coefficient μ on the body geometric dimensions is examined considering the parameters of gap width Bg,body draft D,body breadth ratio Br and body number n(n = 2,3),where Br = BB/BA for the case of two bodies(Body A and Body B) with different breadths of BA and BB,*** was confirmed that the damping coefficient used for the potential flow model is not sensitive to the geometric dimensions and spatial *** was found that μ∈ [0.4,0.5] may guarantee the variation of hg/h0 with kh to be generally in good agreement with the experimental data and the results of viscous fluid model,where hg is the excited wave height in narrow gaps under various dimensionless incident wave frequencies kh,h0 is the incident wave height,k = 2π/L is the wave number and h is the water depth.

关键词： narrow gap fluid resonance water wave viscous fluid model potential flow model finite element method boundary element method

Multifractal modelling and spectrum analysis: Methods and applications to gamma ray spectrometer data from southwestern Nova Scotia, canada

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Science China Earth Sciences 2006年第3期49卷 283-294页

作者： ChENG Qiuming1,2 1. State key Lab of Geological Processes and Mineral Resources, China university of Geosciences, Wuhan 430074, China 2. department of Earth and Space Science and Engineering, department of Geography, York university, 4700 keele Street, Toronto, Ontario, M3J 1P3, canada State key Lab of Geological Processes and Mineral Resources China University of Geosciences Wuhan China department of Earth and Space Science and Engineering Department of Geography York University Toronto Canada

Multifractal spectrum, autocorrelation/semivariogram and power spectrum are three dif- ferent functions characterizing a field or measure from different aspects. These functions are interre- lated in such that the autocorrelation/semivariogram and power spectrum are related to the low order statistical moments (0 to 2 nd) which may determine the local multifractality (τ ″(1)) of a multifractal measure. A better understanding of the interrelationships among these three functions is important because, on one hand, the multifractal modelling characterizes a multifractal measure in a more de- tailed manner since it involves moments of all orders. On the other hand, the commonly used semivariogram and power spectrum functions can be used as alternatives to study the dominant mul- tifractal properties around the mean measure. Moreover, semivariogram and power-spectrum func- tions provide spatial and spectral information, which is highly valued in geological applications. A new fractal relation found between area and power-spectrum will be useful for investigation of new meth- ods of spatial-spectral analysis for pattern recognition, anomaly separation, classification, etc. These results have been demonstrated with the case study of modelling gamma ray spectrometer data from the mineral district, southwestern Nova Scotia, canada. The results have shown that the values of uranium (U), thorium (Th) and potassium (k) may possess monofractal properties whereas the ratios of these values show high multifractality. The values of the ratios U/k and U/Th show relatively large variances and may provide more information for distinguishing the distinct phases of the granites, country rocks as well as possible gold mineralization-associated regional hydrothermal alteration zones. In addition, the power spectra for U, Th, k, U/Th and U/k consistently show two distinct power-law relationships for two ranges of wave number 12≤ω ≤160 km and 0≤ω ≤12 km. These properties might provide usefu

关键词： gamma ray spectrometer data, gold mineralization, alteration zones, multifractal modelling, spectral analysis, GIS.

Genesis of Rare Element Mineralized Granites in Southern China:Evidence from Melt and Fluid Inclusions

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Journal of Earth Science 1993年第1期12卷 64-69,138页

作者： Chen Ziying Xia WeihuaChina university of Geosciences, Wuhan 430074Anthony E.Williams-Jonesdepartment of Earth and Planetary Sciences, mcgill university, 3450 university Street, montreal,Quebec, canada, h3. 2A7

Rare element mineralized granites of me Yanshan period in Southern China are characterized by high contents of SiO2,Na2o,k2O,and F and are enriched in Nb,Ta,REE,W,Sn,Be and Li .Opinions differed over whether they are of metasomatk or magmatic origin .In this paper ,we present results of a study on melt and fluid inclusions in topaz-albite feldspar granite from Limo Nb-Ta-W-Sn granite and 414 Ta-Li albhe granite .Our data, which come from 15 mineralized granites, provide strong support magmatic origin .Mett inclusions are recognized in both topaz and quartz, and are associated with primary gas-rich *** of a Nb (Ta) -bearing mineral and cassiterite are also commonly present as inclusions in the topaz .Multiphase (mett+fluid) inclusions are observed in some quartz from granites and granite-related pegmatite .Mett inclusions start to mett at a temperature of approximately 540 ℃ in topaz and 650 ℃ in quartz .Final homogenization temperature is 700-900 ℃ in quartz ,700-800℃ in topaz and 440-550 ℃ for primary gas-rich inclusions coexisting with mett inclusions in topaz .The fluid inclusion data show that there was a continuous evobtion of the fluid from Nb-Ta granites and pegmatites to W-Sh hydrothermal vein. The coexistence of mett .vapour-rich fluid inclusions, and rare element crystaffites in topaz and quartz indicates that these minerals crystallized from a vapour-saturated mett enriched in Na.k,F and rare elements (Li,Be,Nb,Ta) .The evidence from fluid inclusion study shows that the possible genesis of the rare dement mineralization inLi-F granites of Yanshan period in Southern China results from magmatic differentiation .

关键词： Nb-Ta granite genesis fluid inclusion melt indnskn topaz Southem China .

Crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal khajuria M.Manhas A.k.Bedyal Ankush Vij h.C.Swart Vinay kumar department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Urotensin Ⅱ accelerates cardiac fibrosis and hypertrophy of rats induced by isoproterenol

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Acta Pharmacologica Sinica 2007年第1期28卷 36-43页

作者： Yong-gang ZhANG~(2,5) Yu-guang LI~2 Bao-guo LIU~3 Rui-hong WEI~2 Dong-ming WANG~2 Xue-rui TAN~2 Ding-fang BU~4 Yong-zheng PANG~4 Chao-shu TANG~42 department of Cardiovascular Diseases,First Affiliated hospital,Shantou university Medical College,Shantou 515041,China 3 The Affiliated hospital,Medical School of hebei university of Engineering,hebei 056029,China,4 Institute of Cardiovascular Research,Peking university First hospital,Beijing 100034,China department of Cardiovascular Diseases First Affiliated Hospital Shantou University Medical College Shantou China The Affiliated hospital Medical School of Hebei University of Engineering Hebei China Institute of Cardiovascular Research Peking University First Hospital Beijing China

Aim:To study whether urotensin II（UII）,a potent vasoconstrictive peptide,isinvolved in the development of cardiac hypertrophy and fibrogenesis of ratsinduced by isoproterenol（ISO）.Methods:Thirty male Wistar rats were randomlydivided into 3 *** 1 was the healthy control group,group 2 was the ISOgroup,and group 3 was the ISO+UII *** groups 2 and 3,ISO(5 mg-kg-1.d-1)wasgiven（sc）once daily for 7 *** 3 was also given UII in the first day [3 nmol/kg（5μg/kg）,iv],followed by sc（1.5 μg/kg）twice *** 1 received 0.9% *** receptor（UT）mRNA expression was determined by *** contents ofUII and angiotensin II（Ang II）were determined by *** vitro,the effects of UII on DNA/collagen synthesis of cardiac fibroblasts were deter-mined by [3h]thymidine/[3h]proline ***:The ratio of heartweight/body weight,plasma lactate dehydrogenase activity,myocardialmalondialdehyde and hydroxyproline concentration increased significantly in theISO group,as well as UT mRNA expression,plasma and cardiac UII and ventricu-lar Ang II,compared with the control group（Phe changes of biochemical markers of injury and the degree of cardiac hypertro-phy and *** vitro,5×10～9-5×10-7mol/L UII stimulated[3h]thymidine/[3h]proline incorporation into cardiac fibroblasts in a dose-dependent manner（Phese results suggest that UII was involved in the development ofcardiac fibrosis and hypertrophy by synergistic effects with ISO.

关键词： cardiac remodeling cardiac fibrosis GPR14 receptor urotensin II collagen

Correlation of zeros of automorphic L-functions

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Science China mathematics 2008年第7期51卷 1147-1166页

作者： LIU JianYa1 & YE YangBo1,2 1 School of mathematics,Shandong university,Jinan 250100, China 2department of mathematics,The university of Iowa,Iowa City,IA 52242-1419,USA School of mathematics Shandong University Jinan China department of mathematics The University of Iowa Iowa City USA

We compute the n-level correlation of normalized nontrivial zeros of a product of Lfunctions: L(s, π1) … L(s, π k ), where πj, j = 1, …, k, are automorphic cuspidal representations of GL mj (?A). here the sizes of the groups GL mj (?A) are not necessarily the same. When these L(s, π j ) are distinct, we prove that their nontrivial zeros are uncorrelated, as predicted by random matrix theory and verified numerically. When L(s, π j ) are not necessarily distinct, our results will lead to a proof that the n-level correlation of normalized nontrivial zeros of the product L-function follows the superposition of Gaussian Unitary Ensemble (GUE) models of individual L-functions and products of lower rank GUEs. The results are unconditional when m 1, …, m k ? 4, but are under hypothesis h in other cases.

关键词： automorphic L-function zero correlation Selberg’s orthogonality conjecture 11F70 11M26 11M41

Interaction of Peristaltic Flow with Pulsatile Couple-Stress Fluid

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生物数学学报 1998年第4期13卷 417-425页

作者： Elsoud S A N kaldas S F Mekheimer k h S(1 department of mathematics,Faculty of Education,Ain shams university,lleliopolis,Cairo,Egypt)(2 department of mathematics,Universyty college for Women,Ain Shams university,Cairo,Egypt and 3 department of Mathemati Ain Shams university 埃及 Al-Azhar university 埃及

The interaction of a purely mean flow with a peristaltic induced flow is investigated within the framework of a two-dimensional *** mathematical model considers a viscous incompressible couple-stress fluid between infinite arallel walls on which a sinusoidal travelling wave is imposed.A perturbation solution to the complete set of Navier-Siokes equations in found for the case in which the frequency of the travelling wave and that of the imposed pressure gradient are *** ratio of the travelling wave amplitude to channel width is assumed to be *** this case a first order steady flow is found to exisi,as contrasted to a second order effect in the absence of the imposed periodic pressure *** effects of the various parameters entering to the problem are discussed numerically.

关键词： Peristallic-couple stress-uniform geometry

Neuroprotection of Insulin against Oxidative Stress-induced Apoptosis in Cultured Retinal Neurons:Involvement of Phosphoinositide 3-kinase/Akt Signal Pathway

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Acta Biochimica et Biophysica Sinica 2006年第4期38卷 241-248页

作者： Xiao-Rui YU~(1,2*) Guo-Rong JIA~1 Guang-Dao GAO~3 Shu-hong WANG~1 Yan hAN~1 Wei CAO~4 1 department of Biochemistry and Molecular Biology, 2 key Laboratory of Environment and Genes Related to Diseases of Ministry of Education, 3 department of Pathobiology,School of Medicine,Xi'an Jiaotong university,Xi'an 710061,China 4.department of Ophthalmology,university of Oklahoma health Science Center,Dean A,McGee Eye Institute,Oklahoma City,Oklahoma 73104,USA department of Biochemistry and Molecular Biology Xi'an Jiaotong UniversityXi'an 710061 China key Laboratory of Environment and Genes Related to Diseases of Ministry of Education Xi'an Jiaotong UniversityXi'an 710061 China department of Pathobiology School of Medicine Xi'an Jiaotong UniversityXi'an 710061 China department of Ophthalmology University of Oklahoma Health Science Center Dean A. McGee Eye InstituteOklahoma City Oklahoma 73104 USA

In order to investigate the neuroprotection of insulin in retinal neurons,we used retinal neuronalculture as a model system to study the protective effects of insulin against h2O2-induced cytotoxicity andapoptotic *** retinal neuronal cultures were grown from retinas of 0-2-day old *** viability was measured by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl-tetrazolium bromide *** cell death was evaluated by the TdT-mediated digoxigenin-dUTP nick-end labeling assay,and byDNA laddering *** 3-kinase （PI3k） activity was measured using phosphoinositide4,5-bisphophate and [γ-32P]ATP as *** blot analysis with anti-phospho-Akt （pS473） antibodywas performed to examine the level of phosphorylated *** observed that treatment with 100μM h2O2for 24 h significantly decreased cell viability and induced apoptotic death of retinal neurons,and that pretreatmentwith 10 nM insulin significantly inhibited or attenuated h2O2-induced cytotoxicity and *** LY294002,a specific PI3k inhibitor,abolished the cytoprotective effect of *** also stronglyactivated both PI3k and the downstream effector *** results suggest that insulin protects retinalneurons from oxidative stress-induced apoptosis and that the PI3k/Akt signal pathway is involved in insulin-mediated retinal neuroprotection.

关键词： apoptosis insulin phosphoinositide 3-kinase/Akt oxidative stress neuroprotection retinal neuronal culture

Effects of Topographic Slopes on hydrological Proecsses and Climate

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Advances in Atmospheric Sciences 2001年第5期18卷 733-741页

作者： Jinliang Liu Climate Processes and Earth Observation Division, Meteorological Service of canada, 4905 Dufferin Street, Downsview, Ontario M3h 5T4, canada han-Ru Cho department of Atmospheric Science, National Central university, Chungli 320, Taiwan Climate Processes and Earth Observation Division Meteorological Service of Canada Downsview Canada National Central university Chungli Taiwan

Based on previous research results on river re-distribution models, a modification on the effects of topographic slopes for a runoff parameterization was proposed and implemented to the NCAR's land sur- face model (LSM). This modification has two aspects firstly, the topographic slopes cause outflows from higher topography and inflows into the lower topography points; secondly, topographic slopes also cause decrease of infiltration at higher topography and increases of infiltration at lower topography. Then changes in infiltration result in changes in soil molsture, surface fluxes and then in surface temperature, and eventual- ly in the upper atmosphere and the climate. This mechanism is very clearly demonstrated in the point bud- gets analysis at the Andes Mountains vicinities. Analysis from a regional scale perspective in the Mackenzie GEWEX Study (MAGS) area, the focus of the ongoing Canadian GEWEX program, shows that the modi- fied runoff parameterization does bring significant changes in the regional surface climate More important- ly, detailed analysis from a global perspective shows many encouraging improvements introduced by the modified LSM over the original model in simulating basic atmospheric climate properties such as thermodynamic features (temperature and humidity). All of these improvements in the atmospheric climate simulation illustrate that the inclusion of topographic effects in the LSM can force the AGCM to produce a more realistic model climate.

关键词： hydrological processes Runoff,Parameterization Topographic slope Climate model Land surface model