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Influence of Silica Fume on Corrosion Behaviour of Reinforced Steel in Different Media

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Journal of Materials Science & Technology 2002年第1期18卷 83-88页

作者： Z.A.El-hadi I.Z.Selim 等 DepartmentofChemistry UniversityCollegeforGirlsAinShamsUniversityEgypt PhysicalChemistryDepartment NationalResearchCenterCairoEgypt

Electrochemical and corrosion behaviour of reinforced steel embedded in cement pastes incorporating different amounts of silica fume as a partial replacement of cement has been studied in chloride and sulphate solutions by using different electrochemical techniques. The results indicate that, while steel passivity degree is low in the control samples' upon soaking in the corrosive media, it has been high in samples incorporating silica fume and increased with increasing silica fume content. The improvement effect of silica fume may be attributed to the pore solution structure of the cement paste, which limits the mobility of aggressive ions near the surface of the steel. The mechanism of steel corrosion due to chloride and sulphate attack and passivation effect of silica fume are discussed.

关键词： Corrosion Reinforced steel Cement pastes Silica fume Aggressive ions

Quantitative Structure-retention Relationship Analysis of Nanoparticle Compounds by GA-PLS,GA-KPLS and L-M ANN

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Chinese Journal of Structural Chemistry 2012年第4期31卷 569-573页

作者： hadi Noorizadeh Abbas Farmany Mehrab Noorizadeh Faculty of Science Islamic Azad University Young Researchers Club Ilam BranchIslamic Azad University

Genetic algorithm and partial least square（GA-PLS）,kernel PLS（KPLS） and Levenberg-Marquardt artificial neural network（L-M ANN） techniques were used to investigate the correlation between retention time（RT） and descriptors for 15 nanoparticle compounds obtained by the comprehensive two-dimensional gas chromatography system（GC × GC）.Application of the dodecanethiol monolayer-protected gold nanoparticle（MPN） column was for a high-speed separation as the second column of GC × *** L-M ANN model with the final optimum network architecture of [13-5-1] gave a significantly better performance than the other *** is the first research on the quantitative structure-retention relationship（QSRR） of nanoparticle compounds using the GA-PLS,GA-KPLS and L-M ANN.

关键词： nanoparticle compounds comprehensive two-dimensional gas chromatography system monolayer-protected gold nanoparticle genetic algorithm-kernel partial least squares Levenberg-Marquardt artificial neural network

Preparation of 1-amidoalkyl-2-naphthol derivatives using barium phosphate nano-powders

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Chinese Chemical Letters 2016年第1期27卷 119-126页

作者： hadi Taghrir Majid Ghashang Mohammad Najafi Biregan Devartment of Chemistry. Science and Research Branch Islamic Azad University Arak Iran Department of Chemistry Faculty of Sciences Najafabad Branch Islamic Azad University Najafabad Iran

Barium phosphate（Ba_3（PO_4）_2） nano-powder was successfully synthesized via a simple precipitation route without any surfactant. The prepared nano-powder was applied for the facile synthesis of 1-amidoalkyl-2-naph... 详细信息

关键词： Multi-component reaction 1-Amidoalkyl-2-naphthol Barium phosphate(Ba_3(PO_4)_2) 2-Hydroxydibenzofuran

Evaluation of CRU TS, GPCC, AgMERRA, and AgCFSR meteorological datasets for estimating climate and crop variables: A case study of maize in Qazvin Province, Iran

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Journal of Arid Land 2022年第12期14卷 1361-1376页

作者： Faraz GORGIN PAVEH hadi RAMEZANI ETEDALI Brian COLLINS Syracuse University Syracuse 13244USA Imam Khomeini International University Qazvin 34149-16818Iran Centre for Crop Science The University of QueenslandBrisbane 4072Australia

In the past few decades,meteorological datasets from remote sensing techniques in agricultural and water resources management have been used by various researchers and *** on the literature,meteorological datasets are not more accurate than synoptic stations,but their various advantages,such as spatial coverage,time coverage,accessibility,and free use,have made these techniques superior,and sometimes we can use them instead of synoptic *** this study,we used four meteorological datasets,including Climatic Research Unit gridded Time Series(CRU TS),Global Precipitation Climatology Centre(GPCC),Agricultural National Aeronautics and Space Administration Modern-Era Retrospective Analysis for Research and Applications(AgMERRA),Agricultural Climate Forecast System Reanalysis(AgCFSR),to estimate climate variables,i.e.,precipitation,maximum temperature,and minimum temperature,and crop variables,i.e.,reference evapotranspiration,irrigation requirement,biomass,and yield of maize,in Qazvin Province of Iran during *** first,data were gathered from the four meteorological datasets and synoptic station in this province,and climate variables were ***,after using the AquaCrop model to calculate the crop variables,we compared the results of the synoptic station and meteorological *** the four meteorological datasets showed strong performance for estimating climate *** and AgCFSR had more accurate estimations for precipitation and maximum ***,their normalized root mean square error was inferior to CRU for minimum ***,they were all very efficient for estimating the biomass and yield of maize in this *** reference evapotranspiration and irrigation requirement CRU TS and GPCC were the most efficient rather than AgMERRA and *** for the estimation of biomass and yield,all the four meteorological datasets were *** sum up,GPCC and AgCFSR were the two best datasets in thi

关键词： climate variables crop variables meteorological datasets precipitation reference evapotranspiration irrigation requirement Iran

Micro-seeding and soft template effects on the control of polymorph and morphology of HMX micro particles in solvent-antisolvent process

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Defence Technology（防务技术） 2017年第6期13卷 392-396页

作者： Sajjad Damiri Shahriar Namvar hadi Panahi Department of Applied Chemistry Maleke-ashtar University of TechnologyShahin-shahrEsfahanIran

A seeding strategy was developed in the preparation of cyclotetramethylenetetranitramine(HMX)explosive micro-particles by solvent-antisolvent method, to control their polymorphs from dangerous gamma(y) type to the desired and standard beta(β) form with the size distribution of <10.0 μm, by using a low concentration of β-HMX fine particles as micro-seed in the antisolvent medium. All products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and dynamic light scattering particle size analyzer. In the next step, the effective factors on the sizes and morphologies of micro-particles in the presence and absence of two soft templates of poly(ethylene glycol)-400(PEG-400) polymer and coconut fatty acid diethanolamide(lauramide) surfactant were investigated. The results of experiments showed that using of water-soluble PEG-400 in the low antisolvent temperatures leads to the production of very spherical particles. Also non-ionic surfactant of lauramide, direct the crystal growth to needle-like structures. The advantages of this method are its capability for the simple production of β-HMX micro-particles in the large scale production process, with the various crystal structures and particles size distributions.

关键词： Micro seeding Polymorph HMX Explosive Micro-particle Solvent-antisolvent process

Sustainability assessment of potato fields using the DEXi decision support system in Hamadan Province, Iran

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Journal of Integrative Agriculture 2018年第11期17卷 2583-2595页

作者： Mohammed Ebrahim Rezaei Morteza Barmaki hadi Veisi Department of Agronomy and Plant Breeding University of Mohaghegh Ardabili Environmental Sciences Research Institute Shahid Beheshti University

Potato is a staple food crop and the most important agricultural commodity, which critically affects food security and economic stability in Hamadan Province, Iran. Ex-ante sustainability appraisal of new cropping systems and their comparisons with conventional systems can increase the efficiencies of innovations and changes within the production process. This study aimed to explore the sustainability levels of potato cropping systems in Hamadan Province, Iran. To this end, DEXi methodology was developed for the sustainability assessment of the cropping systems. For assessing the three dimensions of environmental, economic, and social sustainability in the four systems of traditional potato system （TPS）, Quasi-industrial potato system （QIPS）, industrial potato system （IPS）, and government-promoted potato system （GPPS）, five groups of features were utilized：（1） irrigation method; （2） seed placement; （3） farm machinery use; （4） agrochemical use; and （5） rotation. The impact a^sessments of the cropping systems were based on two, three, and two groups of ecological, social, and economic indicators, respectively. Employment, supply chain, protection, operational difficulty, productivity, profitability, input use, and biodiversity resulted in 21 basic indicators and 13 aggregated indicators, by which the cropping systems were described. The results revealed that GPPS with distinctive economic and social profiles could have a better overall sustainability despite the fact that some indicators like biodiversity could be negatively affected. Finally, three strategies were recommended for the sustainability of GPPS as follows： biodiversity enhancement, input substitution, and integrated water management.

关键词： agricultural sustainability multi-criteria potato

Effect of Nano Clay on Corrosion Protection of Zinc-rich Epoxy Coatings on Steel 37

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Journal of Materials Science & Technology 2016年第11期32卷 1152-1160页

作者： Farhad Tohidi Shirehjini Iman Danaee hadi Eskandari Davood Zarei Abadan Faculty of Petroleum Engineering Petroleum University of Technology Technical Faculty South Tehran Branch Islamic Azad University

Epoxy zinc rich coatings containing clay nanoparticles were prepared and the effect of clay content on the cathodic protection performance of the coatings was evaluated by electrochemical impedance spectroscopy（EIS） and immersion test. Open circuit potential（OCP） measurements and immersion tests were also carried out to better understand the behavior of zinc rich coating. EIS and OCP measurements showed that addition of 1 wt% clay improved the cathodic protection duration and sacrificial properties of the epoxy zinc rich coating. Transmission electron microscopy（TEM） photographs confirmed that clay nanoparticles were successfully dispersed in the coating matrix loaded with 1 wt% clay. Immersion test results indicated that addition of 1 wt% clay nanoparticles in zinc rich epoxy coatings increased the cathodic protection ability of coatings.

关键词： Epoxy coatings Zinc rich Impedance Cathodic protection Clay

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling mode shapes:A semi-analytical non-intrusive approach

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Frontiers of Structural and Civil Engineering 2023年第2期17卷 179-190页

作者： Arash Tavakoli MALEKI hadi PARVIZ Akbar A.KHATIBI Mahnaz ZAKERI Advanced Structures Research Laboratory K.N.Toosi University of TechnologyTehran 16569-83911Iran Faculty of New Sciences and Technologies University of TehranTehran 16569-83911Iran School of Engineering RMIT UniversityMelbourne VIC 3001Australia

In this study,the mechanical properties of the composite plate were considered Gaussian random fields and their effects on the buckling load and corresponding mode shapes were studied by developing a semi-analytical nonintrusive *** random fields were decomposed by the Karhunen−Loève *** strains were defined based on the assumptions of the first-order and higher-order shear-deformation *** equations of motion were extracted using Euler-Lagrange *** probabilistic response space was obtained by employing the nonintrusive polynomial chaos ***,the effect of spatially varying stochastic properties on the critical load of the plate and the irregularity of buckling mode shapes and their sequences were studied for the first *** findings showed that different shear deformation plate theories could significantly influence the reliability of thicker plates under compressive *** is suggested that a linear relationship exists between the mechanical properties’variation coefficient and critical loads’variation ***,in modeling the plate properties as random fields,a significant stochastic irregularity is obtained in buckling mode shapes,which is crucial in practical applications.

关键词： uncertain composite plate stochastic assume mode method Karhunen−Loève theorem polynomial chaos approach plate buckling irregularity in buckling mode shapes

Real-time determination of sandy soil stiffness during vibratory compaction incorporating machine learning method for intelligent compaction

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1609-1625页

作者： Zhengheng Xu hadi Khabbaz Behzad Fatahi Di Wu School of Civil and Environmental Engineering University of Technology SydneySydneyAustralia

An emerging real-time ground compaction and quality control, known as intelligent compaction(IC), has been applied for efficiently optimising the full-area compaction. Although IC technology can provide real-time assessment of uniformity of the compacted area, accurate determination of the soil stiffness required for quality control and design remains challenging. In this paper, a novel and advanced numerical model simulating the interaction of vibratory drum and soil beneath is developed. The model is capable of evaluating the nonlinear behaviour of underlying soil subjected to dynamic loading by capturing the variations of damping with the cyclic shear strains and degradation of soil modulus. The interaction of the drum and the soil is simulated via the finite element method to develop a comprehensive dataset capturing the dynamic responses of the drum and the soil. Indeed, more than a thousand three-dimensional(3D) numerical models covering various soil characteristics, roller weights, vibration amplitudes and frequencies were adopted. The developed dataset is then used to train the inverse solver using an innovative machine learning approach, i.e. the extended support vector regression, to simulate the stiffness of the compacted soil by adopting drum acceleration records. Furthermore, the impacts of the amplitude and frequency of the vibration on the level of underlying soil compaction are *** proposed machine learning approach is promising for real-time extraction of actual soil stiffness during compaction. Results of the study can be employed by practising engineers to interpret roller drum acceleration data to estimate the level of compaction and ground stiffness during compaction.

关键词： Intelligent compaction Machine learning method Finite element modelling Acceleration response