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Pedosphere 2009年第5期19卷 631-641页

作者： M.j.KHAN D.L.jONES Department of Soil and Environmental Sciences NWFP Agricultural UniversityPeshawar(Pakistan) School of Agricultural and Forest Sciences University of WalesBangorGwynedd LL57 2UW(UK)

Soil samples from a historic copper mine tailing site at the Parys Mountain,North Wales(UK) were amended with green waste compost(GC),GC+30% sewage sludge(GCS),lime and diammonium phosphate(DAP),to determine the effect of amendments on DTPA-and Ca(NO3)2-extractable metals in the mine tailing and on the phytoavailability of heavy metals by a lettuce(Lactuca sativa L.).Both compost were added at the rate of 10% by weight,lime was added as calcium carbonate equivalent(pH = 7) and DAP at a 2300 mg kg-1 soil *** experiment was arranged in randomised complete design with three replicates in pots under control *** of lime resulted in the largest reduction in metal extractability with DTPA and Ca(NO3)2 and phytoavailability of Cu,Fe and Zn while DAP was effective in lowering Pb extractability and *** exception of Zn,all other metals extracted decreased with time after amendment *** distribution of heavy metals between and within the four procedures of potentially bioavailable sequential extraction(PBAse) varied significantly(P se se1 and Cu,Pb(P sence of N in DAP(through N leaching) may restrict its chances for remediation of contaminated sites.

关键词： lettuce metal uptake potentially bioavailable sequential extraction

Dielectric confinement on exciton binding energy and nonlinear optical properties in a strained Zn_(1-x_(in))Mg_(x(in))se/Zn_(1-x(out))Mg_(x(out))se quantum well

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journal of semiconductors 2012年第9期33卷 1-7页

作者： j.Abraham Hudson Mark A.john Peter Department of Physics NPR Arts&Science CollegeNathamDindigul-624401India Department of Physics Government Arts CollegeMelur-625106MaduraiIndia

The band offsets for a Zn1-xin Mgxin se/Zn1-xout Mgxout se quantum well heterostructure are determined using the model solid theory. The heavy hole exciton binding energies are investigated with various Mg alloy contents. The effect of mismatch between the dielectric constants between the well and the barrier is taken into account. The dependence of the excitonic transition energies on the geometrical confinement and the Mg alloy is discussed. Non-linear optical properties are determined using the compact density matrix approach. The linear, third order non-linear optical absorption coefficient values and the refractive index changes of the exciton are calculated for different concentrations of magnesium. The results show that the occurred blue shifts of the resonant peak due to the Mg incorporation give the information about the variation of two energy levels in the quantum well width.

关键词： interband emission energy exciton binding energy quantum well

On continuum modeling using kinetic-frictional models in high shear granulation

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Particuology 2014年第2期12卷 124-127页

作者： P.j.Abrahamsson S.Sasic A.Rasmuson Department of Chemical Engineering Chalmers University of TechnologySE-412 96 GothenburgSweden Department of Applied Mechanics Division of Fluid DynamicsChalmers University of TechnologySE-412 96 GothenburgSweden

This short communication demonstrates why extreme caution has to be taken when applying conven- tional kinetic-frictional closures to continuum modeling of high shear granulation （HSG）, Conventional models refer to closure laws where the kinetic and frictional stresses are summed up to obtain the total stress field, In the simple, dense, and sheared system ofa Couette shear cell, the effect of the lack of scale separation on the model predictions is examined, both quantitatively and qualitatively. It is observed that the spatial resolution has a significant effect on the magnitude of the kinetic and frictional contributions to the solid phase stresses. With this new investigation and previous studies of HSG, it is concluded that conventional kinetic-frictional models are inadequate for continuum modeling of HSG.

关键词： Kinetic theory of granular flowFrictional stressseparation of scalesHigh shear granulationCouette shear cell

3D Flow Past Transonic Turbine Cascade se 1050-Experiment and Numerical Simulations

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journal of Thermal Science 2013年第4期22卷 311-319页

作者： D.imurda j.Fürst M.Luxa Institute of Thermomechanics AS CR v.v.i.Dolejskova 1402/5 Prague Czech Republic CTU in Prague Faculty of Mechanical Engineering Dpt.of Technical MathematicsKarlovo Náměstí 13 Prague Czech Republic

This paper is concerned with experimental and numerical research on 3D flow past prismatic turbine cascade se1050 （known in QNET network as open test case se1050）. The primary goal was to assess the influence of the inlet velocity profile on the flow structures in the interblade channel and on the flow field parameters at the cascade exit and to compare these findings to results of numerical simulations. Investigations of 3D flow past the cascade with non-uniform inlet velocity profile were carried out both experimentally and numerically at subsonic （M2 = 0.8） and at transonic （M2 = 1.2） regime at design angle of incidence. Experimental data was obtained using a traversing device with a five-hole conical probe. Numerically, the 3D flow was simulated by open source code OpenFOAM and in-house code. Analyses of experimental data and CFD simulations have revealed the development of distinctive vortex structures resulting from non-uniform inlet velocity profile. Origin of these structures results in increased loss of kinetic energy and spanwise shift of kinetic energy loss coefficient distribution. Differences found between the subsonic and the transonic case confirm earlier findings available in the literature. Results of CFD and experiments agree reasonably well.

关键词： blade cascade vortex structures transonic flow CFD

Die Casting Mold Design of the Thin-walled Aluminum Case by Computational Solidification Simulation

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journal of Materials Science & Technology 2008年第3期24卷 383-388页

作者： Young-Chan Kim Chang-seog Kang jae-Ik Cho Chang-Yeol jeong se-Weon Choi Sung-Kil Hong Korea Institute of Industrial Technology Chonnam National University

Recently, demand for the lightweight alloy in electric/electronic housings has been greatly increased. However, among the lightweight alloys, aluminum alloy thin-walled die casting is problematic because it is quite difficult to achieve sufficient fluidity and feedability to fill the thin cavity as the wall thickness becomes less than 1mm. Therefore, in this study, thin-walled die casting of aluminum （Al-Si-Cu alloy： ALDC 12） in size of notebook computer housing and thickness of 0.8 mm was investigated by solidification simulation （MAGMA soft） and actual casting experiment （Buhler Evolution B 53D）. Three different types of gating design, finger, tangential and split type with 6 vertical runners, were simulated and the results showed that sound thin-walled die casting was possible with tangential and split type gating design because those gates allowed aluminum melt to flow into the thin cavity uniformly and split type gating system was preferable gating design comparing to tangential type gating system at the point of view of soundness of casting and distortion generated after solidification. Also, the solidification simulation agreed well with the actual die-casting and the casting showed no casting defects and distortion.

关键词： Aluminum casting alloy Thin-wall die casting Solidification simulation

selenium Deficiency in serbia and Possible Effects on Health

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Biomedical and Environmental Sciences 1997年第2期10卷 300-306页

作者： Z·j·MAKSIMOVIC IVANADjUjIC serbianAcademyofSciencesandArts KnezMihajlova3511000BelgradeYugoslavia InstituteofChemistry Technol

Ten years study of selenium status in stream sediments, rocks, soils, water, cereal crops and food, as well as in the human tissues, has shown a se deficiency in most parts of this country. Some of the results are presented and discussed, especially in connection with etlology of Balkan nephropathy and high incidence of urinary tract tumors in endemic areas

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Analysis of mesoscale effects in high-shear granulation through a computational fluid dynamics-population balance coupled compartment model

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Particuology 2018年第1期16卷 1-12页

作者： P.j. Abrahamsson P. Kvist G. Reynolds X. Yu I. Niklasson Bjorn M.j. Hounslow A. Rasmuson Department of Chemical and Biological Engineering Chalmers University of Technology SE-412 96 Gothenburg Sweden Pharmaceutical Development AstraZeneca Macclesfield SK10 2NA UK European Bioenergy Research Institute (EBRI) School of Engineering and Applied Science Aston University Birmingham B4 7ET UK AstraZeneca Pharmaceutical and Analytical R&D Molndal SE-431 83 Moldnal Sweden Department of Chemical and Biological Engineering University of Sheffield Sheffield SI 3JD UK

There is a need for mesoscale resolution and coupling between flow-field information and the evolution of particle properties in high-shear granulation. We have developed a modelling framework that com- partmentalizes the high-shear granulation process based on relevant process parameters in time and space. The model comprises a coupled-flow-field and population-balance solver and is used to resolve and analyze the effects of mesoscales on the evolution of particle properties. A Diosna high-shear mixer was modelled with microcrystalline cellulose powder as the granulation material. An analysis of the flow-field solution and compartmentalization allows for a resolution of the stress and collision peak at the impeller blades. Different compartmentalizations showed the importance of resolving the impeller region, for aggregating systems and systems with breakage. An independent study investigated the time evolution of the flow field by changing the particle properties in three discrete steps that represent pow- der mixing, the initial granulation stage mixing and the late stage granular mixing. The results of the temporal resolution study show clear changes in collision behavior, especially from powder to granular mixing, which indicates the importance of resolving mesoscale phenomena in time and space.

关键词： High-shear wet granulation Population-balance model Compartment model Computational fluid dynamics

Differences in East Asian summer monsoon responses to Asian aerosol forcing under different emission inventories

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Advances in Climate Change Research 2022年第3期13卷 309-322页

作者： Chen-se WANG Zhi-Li WANG Ya-Dong LEI Hua ZHANG Hui-Zheng CHE Xiao-Ye ZHANG Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China State Key Laboratory of severe Weather and Key Laboratory of Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China

Opposite anthropogenic aerosol emission trends in Asia can lead to different responses of the ***,we examined the responses of the East Asian summer monsoon(EASM)to changes in Asian anthropogenic aerosol emissions during 2006-2014 using a global aerosol/atmospheric chemistry-climate coupled model(BCC_AGCM2.0_CUACE/Aero)with two sets of emission inventories:the Community Emissions Data System(CEDS)inventory adopted by the Coupled Model Intercomparison Project Phase 6(CMIP6)and the inventory developed at Peking University(PKU).The changes in Asian anthropogenic aerosol emissions during 2006-2014 between the two inventories were remarkably different,particularly in eastern China where completely opposite trends were observed(i.e.,increase in the CEDS inventory,but significant reduction in the PKU inventory).The perturbation simulations with the Asian anthropogenic aerosol forcing from the two inventories showed opposite changes in aerosol optical depth,aerosol effective radiative forcing,cloud liquid water path,and total cloud cover in eastern *** simulated‘dipole-type’changes(i.e.,increase in India but decrease in China)in Asian aerosols and the resulting changes in local radiation budget under the PKU inventory were consistent with the corresponding *** summer surface temperatures over eastern China decreased by 0-0.4 K because of the Asian anthropogenic aerosol forcing under the CEDS inventory,while they increased by 0.1-0.8 K under the PKU *** weakening of the EASM index caused by the Asian aerosol forcing under the PKU inventory was twofold greater than that under the CEDS inventory(−0.4 vs.−0.2).The Asian‘dipole-type’aerosol forcing contributed to the observed summer‘southern drought and northern flood’phenomenon in eastern China during *** slow ocean-mediated response to the regional‘dipole-type’aerosol forcing dominated the weakening of the EASM circulation and the precipitation changes in eastern China in the tot

关键词： Asian aerosol emissions Effective radiative forcing East Asian summer monsoon Precipitation Ocean response

Simulation of 3D Porous Media Flows with Application to Polymer Electrolyte Fuel Cells

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Communications in Computational Physics 2013年第3期13卷 851-866页

作者： N.I.Prasianakis T.Rosen j.Kang j.Eller j.Mantzaras F.N.Buchi Combustion Research Laboratory Paul Scherrer InstituteVilligen PSI 5232Switzerland Electrochemistry Laboratory Paul Scherrer InstituteVilligen PSI 5232Switzerland Linne FLOW Centre KTH MechanicsSE-10044 StockholmSweden

A 3D lattice Boltzmann(LB)model with twenty-seven discrete velocities is presented and used for the simulation of three-dimensional porous media *** accuracy in combination with the half-way bounce back boundary condition is *** properties of the gas diffusion layers that are used in polymer electrolyte fuel cells can be determined with this *** in samples that have been obtained via X-ray tomographic microscopy,allows to estimate the values of permeability and relative effective ***,the computational LB results are compared with the results of other numerical tools,as well as with experimental values.

关键词： Porous media GDLs lattice Boltzmann fuel cells fluid dynamics

A MONTE CARLO SIMULATION OF seCONDARY ELECTRON AND BACKSCATTERED ELECTRON IMAGES IN SCANNING ELECTRON MICROSCOPY

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 351-355页

作者： H.M.Li Z.j.Ding HefeiNationalLaboratoryforPhysicalSciencesatMicroscaleandDepartmentofPhysics UniversityofScienceandTechnologyofChinaHefei230026China

A new parallel Monte Carlo simulation method of secondary electron (se) and back scattered electron images (Bse) of scanning electron microscopy (seM) for a com plex geometric structure has been developed. This paper describes briefly the si mulation method and the modification to the conventional sampling method for the step length. Example simulation results have been obtained for several artifici al structures.

关键词： Monte Carlo seM secondary electrons backscattered electrons,