检索结果-南通市图书馆

Computer-aided Prediction of the ZrO_2 Nanoparticles' Effects on Tensile Strength and Percentage of Water Absorption of Concrete Specimens

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2012年第1期28卷 83-96页

作者： Ali Nazari Shadi riahi Department of Materials Science and Engineering Saveh BranchIslamic Azad University

In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing ZrO2 nanoparticles have been developed at different ages of curing. For building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models were arranged in a format of eight input parameters that cover the cement content, nanoparticle content, aggregate type, water content, the amount of superplasticizer, the type of curing medium, age of curing and number of testing try. According to these input parameters, in the neural networks and genetic programming models, the split tensile strength and percentage of water absorption values of concretes containing ZrO2 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that two models have strong potential for predicting the split tensile strength and percentage of water absorption values of concretes containing ZrO2 nanoparticles. It has been found that neural network （NN） and gene expression programming （GEP） models will be valid within the ranges of variables. In neural networks model, as the training and testing ended when minimum error norm of network gained, the best results were obtained and in genetic programming model, when 4 genes were selected to construct the model, the best results were acquired. Although neural network have predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.

关键词： Concrete Curing medium Zr02 nanoparticles Artificial neural network Geneticprogramming Split tensile strength Percentage of water absorption

Effects of CuO Nanoparticles on Microstructure,Physical,Mechanical and Thermal Properties of Self-Compacting Cementitious Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2011年第1期27卷 81-92页

作者： Ali Nazari Shadi riahi Department of Technical and Engineering Sciences Islamic Azad University(Saveh Branch)

In the present study,split tensile strength of self-compacting concrete with different amount of CuO nanoparticles has been *** nanoparticles with the average particle size of 15 nm were added partially to self compacting concrete and split tensile strength of the specimens has been *** results indicate that CuO nanoparticles are able to improve the split tensile strength of self compacting concrete and recover the negative effects of polycarboxylate superplasticizer on split tensile *** nanoparticle as a partial replacement of cement up to 4 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount at the early ages of *** increase of the CuO nanoparticles more than 4 wt% causes the decrease of the split tensile strength because of unsuitable dispersion of nanoparticles in the concrete *** peak appearance in conduction calorimetry tests,more weight loss in thermogravimetric analysis and more rapid appearance of related peaks to hydrated products in X-ray diffraction（XRD） results all also indicate that CuO nanoparticles up to4 wt% could improve the mechanical and physical properties of the ***,CuO nanoparticles could improve the pore structure of concrete and shift the distributed pores to harmless and few-harm pores.

关键词： Self-compacting concrete(SCC) CuO nanoparticles Split tensile strength Thermogravimetric analysis(TGA) X-ray diffraction(XRD) Pore structure

TWO DIMENSIONAL MELLIN TRANSFORM IN QUANTUM CALCULUS

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2018年第2期38卷 546-560页

作者： Kamel BRAHIM Latifa riahi Faculty of Sciences of Tunis. University of Tunis El Manar Tunisia

In this article, we introduce the two dimensional Mellin transform M4（f）（s,t）, give some properties, establish the Paley-Wiener theorem and Plancherel formula, present the Hausdorff-Young inequality, and find seve... 详细信息

关键词： Quantum calculus Two dimensional Mellin transform q-Double integral

TiO_2 nanoparticles' effects on properties of concrete using ground granulated blast furnace slag as binder

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第11期54卷 3109-3118页

作者： NAZARI Ali riahi Shadi Department of Materials Science and Engineering Saveh Branch Islamic Azad University Saveh lran

In the present study, compressive strength, pore structure, thermal behavior and microstrncture characteristics of concrete containing ground granulated blast furnace slag and TiO2 nanoparticles as binder were investigated. Portland cement was replaced by different amounts of ground granulated blast furnace slag and the properties of concrete specimens were investigated. Al- though it negatively impacts the properties of concrete at early ages, ground granulated blast furnace slag up to 45 wt% was found to improve the physical and mechanical properties of concrete at later ages. TiO2 nanoparticles with the average particle size of 15 nm were partially added to concrete with the optimum content of ground granulated blast furnace slag and physical and mechanical properties of the specimens were measured. TiO2 nanoparticle as a partial replacement of cement up to 3 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount at the early age of hydration and hence increase compressive strength of concrete. The increased TiO2 nanoparticles＇ content of more than 3 wt% may cause reduced compressive strength because of the decreased crystalline Ca（OH）2 content required for C-S-H gel formation and unsuitable dispersed nanoparticles in the concrete matrix. TiO2 nanoparticles could improve the pore structure of concrete and shift the distributed pores to harmless and less-harm pores.

关键词： concrete ground granulated blast furnace slag TiO2 nanoparticles compressive strength pore structure

Lead removal from aqueous medium using fruit peels and polyaniline composites in aqueous and non-aqueous solvents in the presence of polyethylene glycol

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2022年第4期35卷 253-259页

作者： Iman Farirzadeh Majid riahi Samani Davood Toghraie Department of Civil Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran

In the present study,composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous *** tests were conducted in batch mode using the most efficient adsorbent,and the effects of medium pH,initial lead concentration,contact time,adsorbent dosage,and adsorption isotherms were *** results showed that all composites were more efficient in lead removal compared to the fruit peels *** highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L^(-1) Poly ethylene *** composite showed 95.96%lead adsorption at pH=6,the contact time of 90 min,the initial lead concentration of 25 mg·L^(-1),and an adsorbent concentration of 8 g·L^(-1).Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and Freundlich models,but the Langmuir model was more fitted than ***,some characteristics of the composites,such as chemical composition(XRD analysis),structure,and morphology(SEM analysis)and functional groups(FTIR analysis),were studied.

关键词： Adsorption Banana peel Composites Pollution Polyaniline

Modeling the Facies of Reservoir Using Seismic Data with Missing Attributes by Dissimilarity Based Classification

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2017年第4期28卷 703-708页

作者： Majid Bagheri Mohammad Ali riahi Institute of Geophysics University of TehranTehran 14115-6466Iran

Using seismic attributes as features for classification in feature space, in various aims such as seismic facies analysis, is conventional for the purpose of seismic interpretation. But sometimes seismic data may have no attributes or it is hard to define a small and relevant set of attributes in some applica- tions. Therefore, employing techniques that perform facies modeling without using attributes is neces- sary. In this paper we present a new method for facies modeling of seismic data with missing attributes that called dissimilarity based classification. In this method, classification is based on dissimilarities and facies modeling will be done in dissimilarity space. In this space dissimilarities consider as new features instead of real features. A support vector machine as a powerful classifier was employed in both feature space （feature-based） and dissimilarity space （feature-less） for facies analysis. The proposed feature-less and feature-based classification is applied on a real seismic data from an Iranian oil field. Facies model- ing using seismic attributes provide better results, but the feature-less classification outcome is also satis- factory and the facies correlation is acceptable. Indeed, the power of attributes to discriminate different facies causes to that facies analysis using attributes provide more reliable results comparing to feature- less facies analysis.

关键词： facies analysis dissimilarity feature seismic attributes classification support vector- classifier.

Computer-aided design of the effects of Cr_2O_3 nanoparticles on split tensile strength and water permeability of high strength concrete

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第3期54卷 663-675页

作者： Ali NAZARI Shadi riahi Department of Technical and Engineering Sciences Islamic Azad University Saveh Branch

In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing Cr2O3 nanoparticles have been developed at different ages of curing. For purpose of building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models are arranged in a format of 8 input parameters that cover the cement content, nanoparticle content, aggregate type, water content, the amount of superplasticizer, the type of curing medium, age of curing and number of testing try. According to these input parameters, in the neural networks and genetic programming models the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that every two models have strong potential for predicting the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles. It has been found that NN and GEP models will be valid within the ranges of variables. In neural networks model, as the training and testing ended when minimum error norm of network was gained, the best results were obtained and in genetic programming model, when 4 genes were selected to construct the model, the best results were acquired. Although neural network has predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.

关键词： concrete curing medium Cr2O3 nanoparticles artificial neural network genetic programming split tensile strength percentage of water absorption

Characterization of porous Ti-bioglass composite produced by mechanical milling and space holder sintering

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2015年第9期34卷 638-644页

作者： Saeed riahi Mohammad Rajabi Sayed Mahmood Rabiee Department of Mechanical Engineering Babol Noshirvani University of Technology

In this study, porous titanium-10 wt% bioglass(BG) composites were fabricated by the process of combining mechanical alloying with space holder sintering. The pore morphology and phase constituents of the milled powders and porous compacts were characterized by scanning electron microscopy(SEM), X-ray diffractometry(XRD), and Fourier transform infrared spectroscopy(FT-IR). The mechanical properties were determined by running compression test. The porosity of the sintered samples shows a downward trend with the increase of milling time. As the porosity increases, both the compressive strength and elastic modulus decrease. The results illustrate that the fabricated porous compacts with high porosity and suitable mechanical properties have the potential application in bone tissue engineering.

关键词： Titanium Bioglass Porous material Mechanical milli

Triad resonant wave interactions in electrically charged jets

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2017年第8期38卷 1127-1148页

作者： S.ORIZAGA D.N.riahi Department of Mathematics University of Arizona Department of Mathematics University of Texas Rio Grande Valley

Nonlinear instability in electrically charged jets is studied using the governing electro-hydrodynamic equations describing stretching and thinning of a liquid jet. A jet flow system subject to both space and time evolving disturbances is considered. At the linear stage, the Rayleigh and conducting jet flow instability modes are *** instability in the flow is explored via triad resonant waves which uncover favorable operating modes not previously detected in the linear study of the problem. In particular, the jet radius is significantly reduced, and the electric field of the jet is properly oriented under the nonlinear study. It is found that taking into account the resonance triad modes provides a better mathematical description of a jet that stretches and thins due to tangential electric field effects. Both linear and nonlinear instability results in the jet flow system are presented and discussed.

关键词： electrically resonant instability hydrodynamic triad Rayleigh governing thinning radius favorable