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

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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

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

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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

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Perfectionism and mental health problems:Limitations and directions for future research

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World Journal of Clinical Cases 2022年第14期10卷 4709-4712页

作者： Nabi nazari Department of Psychology Faculty of Human SciencesLorestan UniversityKhorramabad 65065Iran

Research has indicated that perfectionism is prevalent among adolescents and may be harmful in terms of its association with mental health *** letter aims to create a paradigm for future studies of the ***,we suggest gaps and implications that must be considered at perfectionism future research in terms of assessments,interventions,settings,potential treatments,gender,and social media.

关键词： Perfectionism adolescents Treatment Gender Mental health problems

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

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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

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Situation analysis of cutaneous leishmaniasis in an endemic area,south of Iran

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Asian Pacific Journal of Tropical Medicine 2017年第1期10卷 88-93页

作者： Mansour nazari Saman nazari Ahmad Ali Hanafi-Bojd Ali Najafi Sasan nazari Department of Medical Entomology School of MedicineHamadan University of Medical SciencesHamadanIran Medical student Students Research CenterHamadan University of Medical SciencesHamadanIran Department of Medical Entomology and Vector Control School of Public HealthTehran University of Medical SciencesTehranIran Master of Medical Entomology Health Center of Kazerun cityIran

Objective: To update current situation of the cutaneous leishmaniasis(CL) in Kazerun County,southwest of Iran and to analyze the epidemiological aspects of the disease during 2005-2015,Methods: Data on CL were obtained from the Health Center of Kazerun County,and then were analyzed and mapped using SPSS and Arc GIS 10.3,Results: A total of 700 cases of CL were recorded during the study period with an overall decreasing trend from 2005 to 2015,More than 60% of the patients were inhabitants of rural areas and males were infected more than females,Although there was not a significant difference between gender,job categories,residence and CL infection(P>0.05),age groups were significantly different(P0.05),Most of the acute lesions were found to be present on the hand,leg and face,respectively,The average CL incidence in the study area was calculated as 24.9/100 000 population,A hot spot for the disease was found in southern part of the area(P<0.05),Conclusions: This study revealed that CL is present in Kazerun country,Thus,effective monitoring and sustained suveillance system is crucial in counteracting the disease,and if possible,to eliminate it.

关键词： Cutaneous leishmaniasis Epidemiological study Southern Iran

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Effects of Fe_2O_3 Nanoparticles on Water Permeability and Strength Assessments of High Strength Self-Compacting Concrete

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Journal of Materials Science & Technology 2012年第1期28卷 73-82页

作者： Ali Khoshakhlagh Ali nazari Gholamreza Khalaj Department of Materials Engineering Science and Research BranchIslamic Azad University Department of Materials Engineering Saveh BranchIslamic Azad University

In this work, compressive, flexural and split tensile strength together with coefficient of water absorption of high performance self-compacting concrete containing different amount of Fe2Os nanoparticles have been investigated. The strength and the water permeability of the specimens have been improved by adding Fe2Os nanoparticles in the cement paste up to 4.0 wt%. Fe203 nanoparticle as a foreign nucleation site could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount especially at the early age of hydration and hence increase the strength of the specimens. In addition, Fe203 nanoparticles are able to act as nanofillers and recover the pore structure of the specimens by decreasing harmful pores to improve the water permeability. Several empirical relations have been presented to predict the flexural and the split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of peaks related to hydrated products in X-ray diffraction results indicate that Fe203 nanoparticles up to 4 wt% could improve the mechanical and the physical properties of the specimens.

关键词： Water permeability Fe203 nanoparticles Compressive strength Split tensilestrength Flexural strength

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Engineered FeVO4/CeO2 nanocomposite as a two-way superior electro-Fenton catalyst for model and real wastewater treatment

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Journal of Environmental Sciences 2020年第11期32卷 110-119页

作者： Shahrbanoo Rahman Setayesh Pegah nazari Roghaye Maghbool Department of Chemistry Sharif University of TechnologyTehran 11155-3516Iran

FeVO4/CeO2 was applied in the electro-Fenton(EF)degradation of Methyl Orange(MO)as a model of wastewater *** results of the characterization techniques indicate that FeVO4 with triclinic structure and face-centered cubic fluorite CeO2 maintained their structures during the nanocomposite *** effect of applied current intensity,initial pollutant concentration,initial pH,and catalyst weight was *** MO removal reached 96.31%and chemical oxygen demand(COD)removal 70%for 60 min of the *** presence of CeO2 in the nanocomposite plays a key role in H2O2 electro-generation as a significant factor in the electro-Fenton(EF)*** metal leaching from FeVO4/CeO2 was negligible(cerium 4.1%,iron 4.3%,and vanadium 1.7%),which indicates that the active species in the nanocomposite are strongly interacting with each other and are *** performance of the nanocatalyst in real wastewaters,salty,and binary systems was acceptable and the pollutions were removed *** synergistic effect between V,Fe,and Ce could be account as the reason for the respectable function of FeVO4/*** electron transfer proceeds via Haber-Weiss mechanism.A degradation pathway was proposed through by-products analysis using gas chromatography-mass spectrometry(GC–MS)*** pseudo-first-order kinetic model described the obtained experimental results(R2=0.9906).The electro-Fenton system efficiency was improved by adding *** nanocomposite preserved almost its efficiency after six *** obtained results demonstrate that the synergistic catalyst(FeVO4/CeO2)has the capability to introduce as a promising replacement of conventional catalysts in the electro-Fenton processes with brilliant proficiency.

关键词： Electro-Fenton Methyl Orange Synergistic effect Persulfate FeVO4

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Effects of Al_2O_3 nanoparticles on properties of self compacting concrete with ground granulated blast furnace slag (GGBFS) as binder

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Science China(Technological Sciences) 2011年第9期54卷 2327-2338页

作者： Ali nazari Shadi RIAHI Department of Materials Science and Engineering Saveh BranchIslamic Azad University

In this work, strength assessments and percentage of water absorption of self compacting concrete containing ground granulated blast furnace slag （GGBFS） and A1203 nanoparticles as binder have been investigated. Portland cement was replaced by different amounts of GGBFS and the properties of concrete specimens were investigated. Although it negatively impacts the physical and mechanical properties of concrete at early ages of curing, GGBFS was found to improve the physical and mechanical properties of concrete up to 45 wt% at later ages. A1203 nanoparticles with the average particle size of 15 nm were added partially to concrete with the optimum content of GGBFS and physical and mechanical properties of the specimens were measured. A1203 nanoparticle as a partial replacement of cement up to 3.0 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount at the early ages and hence increase strength and improve the resistance to water permeability of concrete specimens. The increase of the A1203 nanoparticles＇ content by more than 3.0 wt% would cause the reduction of the strength because of the decreased crystalline Ca（OH）2 content required for C-S-H gel formation. Several empirical relationships have been presented to predict flexural and split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of the peaks related to hydrated products in X-ray diffraction results, all indicate that A1203 nanoparticles could improve mechanical and physical properties of the concrete specimens.

关键词： concrete ground granulated blast furnace slag (GGBFS) Al203 nanoparticles compressive strength, flexural and splittensile strength pore structure thermogravimetric analysis conduction calorimetry

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Compressive strength and abrasion resistance of concrete containing SiO_2 and CuO nanoparticles in different curing media

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Science China(Technological Sciences) 2011年第9期54卷 2349-2357页

作者： Shadi RIAHI Ali nazari Department of Materials Science and Engineering Saveh BranchIslamic Azad University

In the present study,abrasion resistance and compressive strength of concrete specimens containing SiO2 and CuO nanoparticles in different curing media have been *** cement was partially replaced by up to 2.0 wt%of SiO2 and CuO nanoparticles and the mechanical properties of the produced specimens were *** the nanoparticles content was found to increase the abrasion resistance of the specimens cured in water and saturated limewater,while this condition was not observed for compressive strength in the both curing *** enhancement of abrasion resistance was higher for the specimens containing SiO2 nanoparticles in both curing *** abrasion resistance and compressive strength of the specimens followed a similar regime as the nanoparticles increased for the specimens cured in saturated limewater,some experimental relationships has been presented to correlate these two properties of concrete for this curing *** the whole,it has been concluded that the abrasion resistance of concrete does not only depend on the corresponding compressive strength.

关键词： nanopartlcles abrasion resistance compressive strength curing medium thermogravimetric analysis XRD SEM

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Synthesis of BSCFO Ceramics Membrane Using a Simple Complexing Method and Experimental Study of Sintering Parameters

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Journal of Materials Science & Technology 2010年第10期26卷 914-920页

作者： Ensieh Ganji Babakhani Jafar Towfighi Khodadad nazari Gas Department Research Institute of Petroleum Industry (RIPI) Chemical Engineering Department Engineering FacultyUniversity of Tarbiat Modares Chemical and Petrochemical Department Research Institute of Petroleum Industry (RIPI)

A new complexing agent Ethylene Diamine N,N,N,N-Tetra N-Acetyl Diamine（EDTNad）,was used for Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCFO） *** chemicals such as ammonia,nitric acid and citric acid were eliminated in comparison to the commonly used EDTA *** agent makes complexing synthesis method a single step and causes more homogeneity in the liquid and solid *** sintering process was studied at temperatures between 1000 to 1200℃,heating-cooling rates of 1,2,5,10℃/min and dwell time of 2,5,10 and 15 ***-sintered membranes were investigated by X-ray diffraction （XRD）,scanning electron microscopy （SEM）,and density *** the SEM images and X-ray diffraction of the BSCFO disks,it could be seen that above 1100℃,crystal intensity decreased,and melting and deformation of the disk *** results show that in restricted temperature range,1000-1100℃,10% temperature increase leads to about a 4.5% density increase but a 200% increase in dwell time leads to about a 4% density *** could be concluded that the effect of temperature on grain growth,porosity and density is more than that of dwell *** also showed that the heating-cooling rate has no significant effect on grain size and density.

关键词： BSCFO Membrane Sintering Grain size Perovskite

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