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heavy metal concentrations in edible bivalves and gastropods available in major markets of the Pearl River Delta

Journal of Environmental Sciences 2001年第2期13卷 210-217页

作者： FANG Zhan-qiang ChEUNG R.Y.h. WONG m.h. Department of Biology South China Normal UniversityGuangzhou 510631China Department of Biology and Chemistry City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong Institute for Natural Resources and Waste management and Department of BiologyHong Kong Bapt ist UniversityKowloon TongHong Kong

molluscs are able to accumulate heavy metals and impose health hazard to consumers. The main objective of the present study is to investigate the heavy metal concentrations in edible bivalves and gastropods available in major markets of the Pearl River Delta. Fourteen species of edible molluscs were purchased from six markets in hong Kong and Guangdong Province. The fresh of these biota were tested for their cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), chromium (Cr), antimony (Sb) and tin (Sn) concentrations (based on wet weight). The results indicated that amongst the 14 edible molluscs, only Cd, Pb, Ni, Cr, Sb and Sn concentrations in three species (Ruditapes philippinarum, Perna viridis and hemifusus tuba) were within the local regulatory limits. Over 60% of bivalve species exceeded maximum permitted levels of Cd (2 mug/g) and Cr (1 mug/g), while over 40% of gastropod species exceeded the maximum levels of Sb (1 mug/g) and Cr (1 mug/g). most of the samples collected from.hong Kong had significantly higher contents of Pb and Sb, but similar levels of Cd, Cu and Zn when compared with samples collected across the border ( p he molluscs purchased in Guangdong markets had higher metal contents than those purchased from the hong Kong markets. When compared with the Provisional Tolerable Weekly Intake or maximum Acceptable Daily Load recommended by FAO/WhO Expert Committee on Food Additives, Cd levels of five species (Anadara ferruginea, Pinna pectinata, Chlamys nobilis, Babylonia lutosa and hemifusus terntanus) and Cr levels of seven species ( Anadara ferruginea, Paphia undulata, Pinna pectinata, Babylonia lutosa, hemifusus terntanus, Cymbium melo and Cipangopaludina chinensis) were higher than both the human daily acceptable limits (for Cd and Cr respectively) and the local regulatory levels (for Cd and Cr respectively).

关键词： heavy metals edible molluscs human health Pearl River Delta

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Thermal Product of Type-E Fast Response Temperature Sensors

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Journal of Thermal Science 2010年第4期19卷 364-371页

作者： h.A.m.hammed h.Salleh m.Z.Yusoff Antonio Campo Department of mechanical Engineering College of EngineeringUniversiti Tenaga NasionalKm 7Jalan Kajang-Puchong43009 KajangSelangorMalaysia Department of mechanical Engineering The University of Texas at San AntonioSan AntonioTX 78249USA

This paper provides practical data for thermal product values of different scratched temperature sensors that can be used for accurate transient heat transfer measurements under hypersonic flow *** effect of using different scratch techniques(abrasive papers and scalpel blades)to form the sensor's junction is *** was observed that the thermal product of a particular sensor depends on the mach number,junction scratch technique, junction location and enthalpy *** was demonstrated that using different scratched technique would produce different thermal product values.

关键词： thermal product fast response temperature sensor hypersonic flow.

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Inverse heat Transfer Problem of Thermal Contact Conductance Estimation in Periodically Contacting Surfaces

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Journal of Thermal Science 2009年第2期18卷 150-159页

作者： m.h.Shojaeefard K.Goudarzi m.Sh.mazidi Dept. of mechanical Engineering Iran University of Science and Technology

The problems involving periodic contacting surfaces have different practical applications. An inverse heat conductionproblem for estimating the periodic Thermal Contact Conductance (TCC) between one-dimensional, constantproperty contacting solids has been investigated with conjugate gradient method (CGm) of function *** method converges very rapidly and is not so sensitive to the measurement errors. The advantage of thepresent method is that no a priori information is needed on the variation of the unknown quantities, since the solutionautomatically determines the functional form over the specified domain. A simple, straight forward techniqueis utilized to solve the direct, sensitivity and adjoint problems, in order to overcome the difficulties associatedwith numerical methods. Two general classes of results, the results obtained by applying inexact simulatedmeasured data and the results obtained by using data taken from an actual experiment are presented. In addition,extrapolation method is applied to obtain actual results. Generally, the present method effectively improves theexact TCC when exact and inexact simulated measurements input to the analysis. Furthermore, the results obtainedwith CGm and the extrapolation results are in agreement and the little deviations can be negligible.

关键词： thermal contact inverse problem conjugates gradient method

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Ab-initio calculations of bandgap tuning of In1-xGaxY(Y=N,P)alloys for optoelectronic applications

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Chinese Physics B 2021年第11期30卷 467-474页

作者： m.hammad Rashid Jamil m m.hmood Q Shahid m Ramay Asif m.hmood A Ghaithan h m Department of Physics Ghazi University City CampusDera Ghazi Khan32200Pakistan Department of Physics COMSATS University IslamabadIslamabad 44000Pakistan Basic and Applied Scientific Research Center(BASRC) College of Science of DammamImam Abdulrahman Bin Faisal UniversityP.O.Box 383Dammam 31113Saudi Arabia Department Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam 31441Saudi Arabia Physics and Astronomy Department College of ScienceKing Saud UniversityRiyadhSaudi Arabia Chemical Engineering Department College of EngineeringKing Saud UniversityRiyadhSaudi Arabia

The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few *** the present article,the bandgap tuning and its influence on optical properties of In1-xGaxN/P,where(x=0.0,0.25,0.50,0.75,and 1.0)alloys are comprehensively analyzed by density functional theory based on full-potential linearized augmented plane wave method(FP-LAPW)and modified Becke and Johnson potentials(TB-mBJ).The direct bandgaps turn from 0.7 eV to 3.44 eV,and 1.41 eV to 2.32 eV for In1-xGaxN/P alloys,which increases their potentials for optoelectronic *** optical properties are discussed such as dielectric constants,refraction,absorption,optical conductivity,and *** light is polarized in the low energy region with minimum *** absorption and optical conduction are maxima in the visible region,and they are shifted into the ultraviolet region by Ga ***,static dielectric constant e1(0)is in line with the bandgap from Penn’s model.

关键词： density functional theory direct bandgap III-V semiconductors tuning of optical band gap solar cell applications

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A New Process for Titanium Aluminides Production from TiO_2

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Journal of materials Science & Technology 2007年第3期23卷 367-372页

作者： A.R.Kamali h.Razavizadeh S.m.m.hadavi Department of materials and metallurgy Engineering IUST University Department of Chemical and materials Engineering maleke Ashtar University

This paper describes a new process for producing titanium aluminides, in particular TiAl, from TiO2 raw material. On the basis of obtained results, the non-completed reaction of TiO2 with Al and Ca in a special reaction vessel results in the production of granulates of titanium aluminides especially Ti3Al and other Ti- Al phases as the metallic product and Ca12Al14O33 as the non-metallic product. By adding KClO4 in the mixture, a nearly completed reaction can be carried out. The products of this reaction are titanium aluminide particularly TiAl as the metallic part and CaAl4O7 （grossite） as the non-metallic slag part. Both product and slag are produced in a separated form. This process, called KRh-method is described in this article. The scanning electron microscopic microstructure of metallic part of the product shows different phases： the matrix phase is TiAI, where the needle form precipitation is TiAl2 and the plate form precipitation includes TiAI and Ti3Al phases. The microstructure of the remelted metallic part indicates dendritic phase with a lamellar structure comprising of TiAl and Ti3Al phases. The interdendritic phase of TiAI is also seen.

关键词： Titanium aluminide Titanium dioxide Grossite KRh process

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Cross-sectional warping and precision of the first-order shear deformation theory for vibrations of transversely functionally graded curved beams

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Applied mathematics and mechanics(English Edition) 2023年第12期44卷 2109-2138页

作者： U.N.ARIBAS m.AYDIN m.ATALAY m.h.OmURTAG Department of Civil Engineering Istanbul Medipol UniversityIstanbul 34810Türkiye

The warping may become an important factor for the precise transverse vibrations of curved ***,the first aim of this study is to specify the structural design parameters where the influence of cross-sectional warping becomes great and the first-order shear deformation theory lacks the precision *** outof-plane vibrations of the first-order shear deformation theory are compared with the warping-included vibrations as the curvature and/or thickness increase for symmetric and asymmetric transversely-functionally graded(TFG)curved *** second aim is to determine the influence of design parameters on the *** circular/exact elliptical beams are formed via curved mixed finite elements(mFEs)based on the exact curvature and *** stress-free conditions are satisfied on three-dimensional(3D)constitutive *** variation of functionally graded(FG)material constituents is considered based on the power-law *** cross-sectional warping deformations are defined over a displacement-type FE *** warping-included mFEs(W-mFEs)provide satisfactory 3D structural characteristics with smaller degrees of freedom(DOFs)compared with the brick *** Newmark method is used for the forced vibrations.

关键词： mixed finite element(mFE) free vibration forced vibration warping exact elliptical beam functionally graded(FG)beam

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Investigation on the dissolution of η phase in a cast Ni-based superalloy

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International Journal of minerals,metallurgy and materials 2013年第1期20卷 42-48页

作者： m.R. Jahangiri h. Arabi S.m.A. Boutorabi School of metallurgy and materials Engineering Iran University of Science and Technology metallurgy Department Niroo Research Institute Center of Excellence for Advanced materials & Processing Iran University of Science and Technology

The dissolution behavior of rI phase has been investigated in a cast Ni-based superalloy. The results showed that the platelets and blocks of η phase were formed within the interdendritic regions of the microstructure. Applying standard solution annealing at 1150-1160℃ for a period of 4 h did not result in the complete dissolution of η phase. For the complete dissolution of η phase without residual incipient melting, a 2-step solution annealing has been recommended. After dissolution at high tem- peratures, the TI phase transforms to two mC-type carbides： one is enriched in Ti, Nb, and Ta, and the other is of （Zr,Ti）C type.

关键词： superalloys nickel alloys phase transitions dissolution heat treatment carbides

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ON ADAPTIVE WAVELET BOUNDARY ELEmENT mEThODS

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Journal of Computational mathematics 2018年第1期36卷 90-109页

作者： h. harbrecht m. Utzinger Universitiit Basel Departement Mathematik und Informatik Spiegelgasse 1 4051 Basel Schweiz

The present article is concerned with the numerical solution of boundary integral e- quations by an adaptive wavelet boundary element method. This method approximates the solution with a computational complexity that is proportional to the solution＇s best N-term approximation. The focus of this article is on algorithmic issues which includes the crucial building blocks and details about the efficient implementation. By numerical examples for the Laplace equation and the helmholtz equation, solved for different geome- tries and right-hand sides, we validate the feasibility and efficiency of the adaptive wavelet boundary element method.

关键词： Boundary element method Wavelets Adaptivity.

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Band head spin determination of triaxial superdeformed bands in ^163,164,165Lu through two-parameter formulae

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Chinese Physics C 2018年第11期42卷 72-77页

作者： honey Sharma h.m. mittal Dr. B.R. Ambedkar National Institute of Technology Jalandhar 144011 India

The two-parameter formulae, i.e. the nuclear softness formula and the power index formula, have been used to obtain the band head spin （I0） of the triaxial superdeformed （SD） bands in ^163Lu（1,2,3,4）, ^164Lu（1,2,3） and ^165Lu（1,2,3）, in the A - 160 mass region. The least squares fitting approach is used. The values of the root mean square （RmS） deviation among the computed and the measured experimental transition energies are obtained by calculating the model parameters. Whenever accurate spins are available, superb agreement is shown between the determined and the measured experimental transition energies. In comparison to the power index formula, the values of band head spin （I0） of the triaxial SD bands in ^163Lu（1,2,3,4）, ^164Lu（1,2,3） and ^165Lu（1,2,3） obtained by the nuclear softness formula are closer to the experimental data. The lowest RmS deviation is also achieved by the nuclear softness formula. hence, the nuclear softness formula works well for obtaining the band head spin （I0） for the triaxial SD bands in ^163Lu（1,2,3,4）, ^164Lu（1,2,3） and ^165Lu（1,2,3） in the A-160 mass region. The dynamic moment of inertia against hω is also studied.

关键词： band head spin nuclear softness formula power index formula triaxial superdeformed bands

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Atmospheric pressure gliding arc discharge plasma treatments for improving germination, growth and yield of wheat

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Plasma Science and Technology 2018年第11期20卷 90-100页

作者： N C ROY m m.hASAN A h KABIR m A REZA m R TALUKDER A N ChOWDhURY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of Rajshahi Rajshahi 6205 Bangladesh Department of Agronomy and Agricultural Extension University of Rajshahi Rajshahi 6205 Bangladesh Depatment of Botany University of Rajshahi Rajshahi 6205Bangladesh Department of Genetic Engineering and Biotechnology University of Rajshahi Rajshahi 6205Bangladesh Bangladesh Council of Scientific and Industrial Research Laboratory Rajshahi Rajshahi 6206Bangladesh

Wheat （Triticum aestivum） seeds were treated with atmospheric pressure gliding arc discharge plasmas to investigate the effects on water absorption, seed germination rate, seedling growth and yield in wheat. The surface architectures and functionalities of the seeds were found to modify due to plasma treatments. 6 rain treatment was provided 95%-100% germination rate. For the treatment duration of 3 and 9 rain the growth activity, dry matter accumulation, leaves chlorophyll contents, longest spikes, number of spikes/spikelet and total soluble protein content in shoots were improved. The grain yield of wheat was increased ,--20% by 6 min treatment with h2O/O2 plasma with respect to control.

关键词： atmospheric pressure gliding arc discharge plasmas wheat germination growth improvement total soluble protein

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