检索结果-南通市图书馆

GIS based ArcPRZM-3 model for bentazon leaching towards groundwater

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2010年第12期22卷 1854-1859页

作者： Tahir ali akbar Henry Lin College of Natural Resources University of Wisconsin-Stevens Point Department of Civil Engineering Schulich School of EngineeringUniversity of Calgary2500 University Drive NWCalgaryAlbertaT2N 1N4Canada Department of Crop and Soil Sciences The Pennsylvania State UniversityUniversity ParkPA 16802USA

Groundwater contamination due to pesticide applications on agricultural lands is of great environmental concern. The mathematical models help to understand the mechanism of pesticide leaching in soils towards groundwater. We developed a user-friendly model called ArcPRZM-3 by integrating widely used Pesticide Root Zone Model version 3 （PRZM-3） using Visual Basic and Geographic Information System （GIS） based Avenue programming. ArcPRZM-3 could be used to simulate pesticide leaching towards groundwater with user-friendly input interfaces coupled with databases of crops, soils and pesticides. The outputs from ArcPRZM-3 could be visualized in user-friendly formats of tables, charts and maps. In this study we evaluated ArcPRZM-3 model by simulating bentazon leaching in soil towards groundwater. ArcPRZM-3 was applied to 37 sites in Woodruff County, Arkansas, USA to observe the daily average dissolved bentazon concentration for soybean, sorghum and rice at a depth of 1.8 m for a period of two years. Nineteen ranks of bentazon leaching potential were obtained using ArcPRZM-3 for all sites having different soil and crop combinations. ArcPRZM-3 simulation results for bentazon were compatible with the field monitored data in term of relative ranking and trend, although some uncertainties exist. This study indicated that macropore flow mechanism would be important in analyzing the effect of irrigation on groundwater contamination due to pesticides. Overall, ArcPRZM-3 could be used to simulate pesticide leaching towards groundwater more efficiently and effectively as compared to PRZM-3.

关键词： ArcPRZM-3 PRZM-3 GIS pesticide leaching groundwater contamination bentazon

EFFECT OF POLYANILINE AS A SURFACE MODIFIER OF TiO_2 NANO-PARTICLES ON THE PROPERTIES OF POLYVINYL CHLORIDE/TiO_2 NANOCOMPOSITES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2013年第3期31卷 481-494页

作者： ali Olad Sepideh Behboudi ali akbar Entezami Polymer Composite Research Laboratory Department of Applied ChemistryFaculty of ChemistryUniversity of Tabriz Polymer Research Laboratory Department of Organic ChemistryFaculty of ChemistryUniversity of Tabriz

Surface of TiO2 nanoparticles was modified with the in situ chemical oxidative polymerization of aniline. Polyaniline modified TiO2 nanoparticles （PANI-TiO2） were characterized with the FT-IR, XRD, SEM and TEM techniques. Results confirmed that PANI was grafted successfully on the surface of TiO2 nanoparticles, therefore agglomeration of nanoparticles decreased dramatically. Polyvinyl chloride nanocomposites filled with 1 wt%-5 wt% of PANI-TiO2 and TiO2 nanoparticles were prepared via the solution blending method. PVC nanocomposites were analyzed with FT-IR, XRD, SEM, TG/DTA, DSC and tensile test techniques. Effect of PANI as surface modifier of nanoparticles was discussed according to the final properties of PVC nanocomposites. Results demonstrated that deposition of PANI on the surface of TiO2 nanoparticles improved the interfacial adhesion between the constituents of nanocomposites, which resulted in better dispersion of nanoparticles in the PVC matrix. Also PVC/PANI-TiO2 nanocomposites showed higher thennal resistance, tensile strength and Young＇s modulus compared to those of unfilled PVC and PVC/TiO2 nanocomposites.

关键词： Polymer nanocomposite Polyvinyl chloride Polyaniline TiO2 nano-additive Surface modification.

Hot Ductility of Severe Plastic Deformed AA6061 Aluminum Alloy

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 322-330页

作者： ali akbar Khamei Kamran Dehghani Mining and Metallurgical Engineering Department Amirkabir University of Technology

The hot ductility of 6061 aluminum alloy,which was subjected to two different severe plastic deformations（SPD）,was studied at different temperatures and strain *** tensile tests were carried out at the temperature range of 300-500 ℃ and at the strain rates of 0.0005-0.01 s^（-1）.The microstructure evolution was characterized using optical microscopy,transmission electron microscopy and X-ray diffraction *** influences of the microstructure after SPD,thermomechanical parameters（temperature and strain rate） and specimen size on the hot formability of this alloy were then *** results show that a decrease in grains/subgrains exhibited significant effect on the hot ductility of SPDed *** constitutive equations were then developed to model the hot formability of the studied *** developed model can be represented by Zener-Hollomon parameter in a hyperbolic sinusoidal equation *** the changes of elongation to failure and Zener-Hollomon parameter indicate that the hot ductility of the alloy is more sensitive to the temperature rather than to the strain *** uniform elongation is independent of the specimen size,but the postnecking elongation increases dramatically as the ratio of l/A^（1/2） decreases.

关键词： Al-Mg-Si alloy Deformation behavior Equal channel angular pressing(ECAP) Rolling Hot tensile deformation

Soil-Structure Interaction Analysis of Jack-up Platforms Subjected to Monochrome and Irregular Waves

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2015年第1期29卷 65-80页

作者： Maziar Gholami KORZANI ali akbar AGHAKOUCHAK Faculty of Civil and Environmental Engineering Tarbiat Modares University

As jack-up platforms have recently been used in deeper and harsher waters, there has been an increasing demand to understand their behaviour more accurately to develop more sophisticated analysis techniques. One of the areas of significant development has been the modelling of spudean performance, where the load-displacement behaviour of the foundation is required to be included in any numerical model of the structure. In this study, beam on nonlinear winkler foundation （BNWF） modeling--which is based on using nonlinear springs and dampers instead of a continuum soil media--is employed for this purpose. A regular monochrome design wave and an irregular wave representing a design sea state are applied to the platform as lateral loading. By using the BNWF model and assuming a granular soil under spudcans, properties such as soil nonlinear behaviour near the structure, contact phenomena at the interface of soil and spudcan （such as uplifting and rocking）, and geometrical nonlinear behaviour of the structure are studied. Results of this study show that inelastic behaviour of the soil causes an increase in the lateral displacement at the hull elevation and permanent unequal settlement in soil below the spudcans, which are increased by decreasing the friction angle of the sandy soil. In fact, spudeans and the underlying soil cause a relative fixity at the platform support, which changes the dynamic response of the structure compared with the case where the structure is assumed to have a fixed support or pinned support. For simulating this behaviour without explicit modelling of soil-structure interaction （SSI）, moment- rotation curves at the end of platform legs, which are dependent on foundation dimensions and soil characteristics, are obtained. These curves can be used in a simplified model of the platform for considering the relative fixity at the soil- foundation interface.

关键词： jack-up platforms wave loading nonlinear dynamic analysis soil-structure interaction (SS1) beam on nonlinear winkler foundation (BNWF)

The new types of wave solutions of the Burger’s equation and the Benjamin-Bona-Mahony equation

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean Engineering and Science 2018年第1期3卷 1-10页

作者： md.Azmol Huda M.ali akbar Shewli Shamim Shanta Mathematics Discipline Khulna UniversityBangladesh Department of Applied Mathematics University of RajshahiBangladesh Department of Mathematics University of RajshahiBangladesh

In this article,we suggest the two variable(G/G,1/G)-expansion method for extracting further general closed form wave solutions of two important nonlinear evolution equations(NLEEs)that model one-dimensional internal waves in deep water and the long surface gravity waves of small amplitude propagating *** method can be regarded as an extension of the(G/G)-expansion *** ansatz of this extension method to obtain the solution is based on homogeneous balance between the highest order dispersion terms and nonlinearity which is similar to the(G/G)method whereas the auxiliary linear ordinary differential equation(LODE)and polynomial solution *** applied this method to find explicit form solutions to the Burger’s and Benjamin-Bona-Mahony(BBM)equations to examine the effectiveness of the method and tested through mathematical computational software *** new exact travelling wave solutions in more general form of these two nonlinear equations are derived by this extended *** method introduced here appears to be easier and faster comparatively by means of symbolic computation system.

关键词： Travelling wave solution Soliton Burger’s equation Benjamin-Bona-Mahony equation.

A study on the compatibility of the generalized Kudryashov method to determine wave solutions

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Propulsion and Power Research 2021年第1期10卷 95-105页

作者： Hemonta Kumar Barman md.Ekramul Islam M.ali akbar Department of Applied Mathematics University of RajshahiRajshahi6205Bangladesh Department of Mathematics Pabna University of Science and TechnologyPabna6600Bangladesh

In this article,we establish solitary wave solutions to the Estevez-MansfieldClarkson(EMC)equation and the coupled sine-Gordon equations which are model equations to analyze the formation of shapes in liquid drops,surfaces of negative constant curvature,*** contriving the generalized Kudryashov *** extracted results introduce several types’solitary waves,such as the kink soliton,bell-shape soliton,compacton,singular soliton,peakon and other sort of soliton for distinct valuation of the unknown *** achieved analytic solutions are interpreted in details and their 2D and 3D graphs are *** obtained solutions and the physical structures explain the soliton phenomenon and reproduce the dynamic properties of the front of the travelling wave deformation generated in the dispersive *** shows that the generalized Kudryashov method is powerful,compatible and might be used in further works to found novel solutions for other types of nonlinear evolution equations ascending in physical science and engineering.

关键词： The nonlinear evolution equations(NLEEs) The Estevez-MansfieldClarkson(EMC)equation The coupled sineGordon equations The generalized Kudryashov method Solitons Analytic solutions

Abundant general solitary wave solutions to the family of KdV type equations

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean Engineering and Science 2017年第1期2卷 47-54页

作者： md.Azmol Huda M.ali akbar Shewli Shamim Shanta Mathematics Discipline Khulna UniversityKhulnaBangladesh Department of Applied Mathematics University of RajshahiRajshahiBangladesh Department of Mathematics University of RajshahiRajshahiBangladesh

This work explores the construction of more general exact traveling wave solutions of some nonlinear evolution equations(NLEEs)through the application of the(G/G,1/G)-expansion *** method is allied to the widely used(G/G)-method initiated by Wang et *** can be considered as an extension of the(G/G)-expansion *** effectiveness,the method is applied to the family of KdV type *** general form solitary wave solutions as well as periodic solutions are successfully obtained through this ***,in the obtained wider set of solutions,if we set special values of the parameters,some previously known solutions are *** approach of this method is simple and elegantly *** been computerized it is also powerful,reliable and effective.

关键词： Nonlinear evolution equation Solitary wave solution Potential KdV equation Complex modified KdV equation

CONTINUOUS FRAME WAVELETS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2012年第2期32卷 807-812页

作者： ali akbar Arefijamaal Narguess Tavallaei Department of Mathematics and Computer Science Sabzevar Tarbiat Moallem UniversitySabzevarIran Department of Pure Mathematics School of Mathematics and Computer ScienceDamghan UniversityDamghanIran

Let π be a unitary representation of a locally compact topological group G on a separable Hilbert space H. A vector ψ∈ H is called a continuous frame wavelet if there exist A, B 〉 0 such that A｜｜Ф｜｜2≤fG｜〈π（G）ψ,Ф｜2dg≤B｜｜Ф｜｜2（Ф∈H）,in which dg is the left Haar measure of G. Similar to the study of wavelets, an essential problem in the study of continuous frame wavelets is how to characterize them under the given unitary representation. Moreover, we investigate a relation between admissible vectors of π and its components.

关键词： Locally compact group unitary representation continuous frame wavelettransform direct integral

Performance and characterization of iron-nickel catalysts for light olefin production

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2010年第4期19卷 422-430页

作者： Mostafa Feyzi ali akbar Mirzaei Department of Chemistry Faculty of SciencesUniversity of Sistan & Baluchestan

A series of x （Fe,Ni）/Al2O3 catalysts （x = 2-12 wt%） were prepared using incipient wetness method and studied for the conversion of synthesis gas to light olefins.6 wt%（Fe,Ni）/Al2O3 catalyst was found to be the optimal catalyst for the production of C2-C4 *** effects of calcination behaviors and operational conditions on the catalytic performance of the optimal catalyst were *** best operational conditions were molar feed ratio H2/CO = 2/1,T = 260 ℃,gas hourly space velocity （GHSV） = 2600 h^-1 and the pressure of 3 ***-izations of both precursors and catalysts were carried out using X-ray diffraction （XRD）,temperature-programmed reduction （TPR）,scanning electron microscopy （SEM）,N2-adsorption-desorption measurement,thermal gravimetric analysis （TGA） and differential scanning calorimetry （DSC）.

关键词： calcination behaviors operational conditions catalytic performance characterization