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Journal of Energy Chemistry 2017年第3期26卷 569-573页

作者： Kobra Ghobadi hamid R.Zare Hossein Khoshro Abbas A.Jafari Department of Chemistry Faculty of ScienceYazd UniversityYazd 89195-741Iran

Benzil,1,2-diphenylethane-1,2-dione, was used as an excellent electrocatalyst for reduction of carbon dioxide, CO. The reduction overpotential of COwas reduced about 900 m V in the presence of a benzil mediator. The chemical reaction of the product of the electrocatalytic reduction of CO,(activated CO,CO) with pyridine at a glassy carbon electrode, GCE, surface and in an acetonitrile-ButNClOsolution was investigated by cyclic voltammetry, chronoamperometry and controlled potential *** chronoamperometry, the catalytic rate constant, k, for the electron transfer between benzil and COwas obtained as 8.1 ± 0.4 ms. The results indicate that pyridine has a strong interaction with the activated CO. The coulometry method was used to obtain the product of the pyridine chemical reaction with CO. The spectral characterizations of FTIR,H andC NmR of the coulometry experiment product proved that the pyridine anion radical, Py, was carboxylated by CO, and isonicotinic acid is the final major product.

关键词： Carbon dioxide Benzil Pyridine electrocarboxylation Catalytic rate constant Isonicotinic acid

Nanocrystalline Growth Activation Energy of Zirconia Polymorphs Synthesized by mechanochemical Technique

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Journal of materials Science & Technology 2014年第4期30卷 387-393页

作者： Taghi Dallali Isfahani Jafar Javadpour Alireza Khav massoud Goodarzi hamid Reza Rezaie Department of materials Science and Engineering Golpayegan University of Technology School of metallurgy and materials Engineering Iran University of Science and Technology(IUST)

The synthesis of ZrO2 by mechanochemical reaction using ZrCI4 and CaO as raw materials and subsequent annealing of the products were investigated. The effect of thermal treatment on the structural evolution and morphological characteristics of the nanopowders was studied by X-ray diffractometry, Raman spectroscopy, transmission electron microscopy, scanning electron microscopy, differential thermal analysis and Rietveld refinement. The results showed that the average crystallite size of Zr02 was less than 100 nm up to around 1100 ℃. The activation energy for ZrO2 nanocrystallite growth during calcination was calculated to be about 13,715 and 27,333 J/too mechanism of the nanocrysta for tetragonal （t-ZrO2） and monoclinic （m-Zr02） polymorphs, respectively. ite growth of the ZrO2 polymorphs during annealing is primarily investigated.

关键词： Zirconia nanoparticles mechanochemical synthesis Characterization methods Activation energy Phase transformation

Scleractinian coral communities of Hormuz Island in the PersianGulf

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Acta Oceanologica Sinica 2022年第12期41卷 48-57页

作者： Yamin Pouryousef Jafar Seyfabadi hamid Rezai Alireza mahvari mohammad Ali Jafari Department of marine Biology Faculty of Marine SciencesTarbiat Modares UniversityNoor 46417Iran Darya Negar Pars Consulting Engineers Tehran 14669Iran Department of Environment Hormozgan Provincial Directorate Bandar Abbas 79168Iran

The abundance and health of scleractinian coral communities of Hormuz Island were *** this purpose,we employed 20 m line intercept transects—12 in the intertidal zone and 15 subtidally to evaluate coral cover and community *** estimated dead coral coverage was 6.21%±0.81%,while live coral coverage was 16.93%±1.81%,considered as very ***,12 genera were recorded,of which Porites with 11.9%±1.4%live cover was the dominant,while Goniopora had the least cover(0.07%±0.08%).Based on mann-Whitney U-test,live coral coverage,dead coral coverage,algal coverage,cover of other benthic organisms and abiotic components showed significant univariate differences between zones(pman correlation test between the abundance of biotic and abiotic components indicated significant negative correlation of live coral and sand with zoantharian and significant positive correlation of algae and other benthic organisms with *** reef health indices used for the corals indicated that,in general,the environmental conditions were not suitable,which could be attributed to both natural and anthropogenic factors,the most important of which was zoantharian’overgrowth on the scleractinian corals in this region.

关键词： scleractinian corals zoantharian reef health indices Hormuz Island Persian Gulf

Gully erosion spatial modelling: Role of machine learning algorithms in selection of the best controlling factors and modelling process

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Geoscience Frontiers 2020年第6期11卷 2207-2219页

作者： hamid Reza Pourghasemi Nitheshnirmal Sadhasivam Narges Kariminejad Adrian L.Collins Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran Department of Geography School of Earth ScienceBharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Department of Watershed and Arid Zone management Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran Sustainable Agriculture Sciences Rothamsted ResearchNorth WykeOkehamptonDevonEX202SBUK

This investigation assessed the efficacy of 10 widely used machine learning algorithms(mLA)comprising the least absolute shrinkage and selection operator(LASSO),generalized linear model(GLm),stepwise generalized linear model(SGLm),elastic net(ENET),partial least square(PLS),ridge regression,support vector machine(SVm),classification and regression trees(CART),bagged CART,and random forest(RF)for gully erosion susceptibility mapping(GESm)in *** location of 462 previously existing gully erosion sites were mapped through widespread field investigations,of which 70%(323)and 30%(139)of observations were arbitrarily divided for algorithm calibration and *** controlling factors for gully erosion,namely,soil texture,annual mean rainfall,digital elevation model(DEm),drainage density,slope,lithology,topographic wetness index(TWI),distance from rivers,aspect,distance from roads,plan curvature,and profile curvature were ranked in terms of their importance using each *** mLA were compared using a training dataset for gully erosion and statistical measures such as RmSE(root mean square error),mAE(mean absolute error),and *** on the comparisons among mLA,the RF algorithm exhibited the minimum RmSE and mAE and the maximum value of R-squared,and was therefore selected as the best *** variable importance evaluation using the RF model revealed that distance from rivers had the highest significance in influencing the occurrence of gully erosion whereas plan curvature had the least *** to the GESm generated using RF,most of the study area is predicted to have a low(53.72%)or moderate(29.65%)susceptibility to gully erosion,whereas only a small area is identified to have a high(12.56%)or very high(4.07%)*** outcome generated by RF model is validated using the ROC(Receiver Operating Characteristics)curve approach,which returned an area under the curve(AUC)of 0.985,proving the excellent forecasting ability of the model

关键词： machine learning algorithm Gully erosion Random forest Controlling factors Variable importance

Facile Growth of Porous Hierarchical Structure of ZnO Nanosheets on Alumina Particles via Heterogeneous Precipitation

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Journal of materials Science & Technology 2013年第10期29卷 915-918页

作者： hamid Tajizadegan majid Jafari mehdi Rashidzadeh Reza Ebrahimi-Kahrizsangi Omid Torabi Department of materials Engineering Najafabad BranchIslamic Azad University Catalysis & Nanotechnology Research Division Research Institute of Petroleum Industry (RIPI)

ZnO nanosheets and nanoflakes were grown on alumina particles in the absence of surfactants via heterogeneous precipitation using urea, zinc acetate and bayerite as precursors. Thermo-gravimetric analysis （TGA）, X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FTIR） were used and the results indicated the formation of only two phases： wurtzite-type ZnO and γ-Al2O3. ZnO nanoflakes were grown on alumina particles in the samples with ZnO content of 40 and 60 wt%, By increasing the ZnO content to 80 wt%, a porous hierarchical structure of ZnO with nanosheet arrays appeared. Both of these nanoflakes and nanosheets were about 40-80 nm in thickness and about 1-2 μm in diameter. It was proposed that Zns（CO3）2（OH）6 nuclei undergo higher growth rates in thin sheets at edges of bayerite particles with a higher surface energy. The Brunauer-Emmett-Teller （BET） measurements proved a reachable high surface area for hierarchical structures of ZnO nanosheets, which could mainly be attributed to their unique growth on alumina particles. Also, UV absorption results revealed that ZnO--Al2O3 compositions still show the UV characteristic absorption of ZnO, which can evidence the presence of photocatalytic properties in ZnO-Al2O3 compositions.

关键词： ZnO Crystal growth Heterogeneous nucleation Hierarchical structures High surface area morphology evolution

Impact of National Egyptian school feeding program on growth,development,and school achievement of school children

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World Journal of Pediatrics 2020年第4期16卷 393-400页

作者： A.m.metwally marwa m.El-Sonbaty L.A.El Etreby E.m.Salah El-Din N.Abdel hamid H.A.Hussien A.m.Hassanin Z.m.monir medical Research Division Community Medicine DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Department of Pediatrics College of MedicineTaibah UniversityMadinahKingdom of Saudi Arabia medical Research Division Child Health DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Agricultural Research Centre GizaEgypt

Background School feeding program(SFP)increases access to education and to better *** study aims to evaluate the effects of SFP on physical growth,cognitive development,psychosocial behavior,and learning achievement of school *** A quasi-experimental study was *** intervention group included 903 pupils in the fifth grade receiving the school meal,while the control group included 886 pupils,matched for age and sex,without *** meal consisted of a pie made of flour fortified with vitamins A,B6,B12,C,thiamin,riboflavin,niacin,folate,calcium,iron,zinc,and *** position,nutritional status,and dietary behavior were *** tests were *** behavior was rated and educational achievement was *** hoc and independent sample t tests were used to detect the association of the studied parameters with the intake of school *** Children who took the meal had better scores on visual memory,auditory vigilance tests(9.71±2.80 vs.7.45±3.25;25.02±3.36 vs.10.82±8.92,respectively,Pmemory test(8.20±2.21vs.7.75±3.05)(Pmeal was the main predictor of visual memory and auditory vigilance(Pmic achievements when combined with family size and meals’frequency(Pmeal improves academic achievements of school children.

关键词： Cognition Growth Performance School feeding

Estimation of demand for wood panels in Iran by the year of 2012.

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Journal of Forestry Research 2009年第A2期20卷 179-182,I0004页

作者： majid Azizi Payam Ghorbannezhad hamid Hatefnia Department of wood and paper sciences and technology College of natural resources University of Tehran P.O. Box： 31585-4314 Karaj lran

Considering increasing rate of Iran population and consumption of wood panels, the authors investigated the per capita consump- tion of wood panels during the years from 1997 to 2007. The exponential smoothing method was used to obtain a per capita consumption panern of wood panels in lran for estimating demand of wood panels by the year of 2012. Results show that the consumption of particleboard, fiberboard, and medium density fiberboard in lran will increase by 33%, 72% and 107 %o, respectively, by the year of 2012; however, the consumption of plywood will increase only by 7% by 2012. The deficient amount of wood panels in Iran is estimated over 1400 000 m^3. The results of this study provide the technique reference for planners of wood panel industries in Iran in capital investment decisions.

关键词： wood panels exponential smoothing estimating Iran wood panel demand

Image Splicing Detection Based on Texture Features with Fractal Entropy

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Computers, materials & Continua 2021年第12期69卷 3903-3915页

作者： Razi J.Al-Azawi Nadia m.G.Al-Saidi hamid A.Jalab Rabha W.Ibrahim Dumitru Baleanu Department of Laser and Optoelectronics Engineering University of TechnologyBaghdad10066Iraq Department of Applied Sciences University of TechnologyBaghdad10066Iraq Department of Computer System and Technology Faculty of Computer Science and Information TechnologyUniversiti MalayaKuala Lumpur50603Malaysia IEEE:94086547 Kuala Lumpur59200Malaysia Department of mathematics Cankaya UniversityBalgat06530AnkaraTurkey Institute of Space Sciences R76900 Magurele-BucharestRomania Department of medical Research China Medical UniversityTaichung40402Taiwan

Over the past years,image manipulation tools have become widely accessible and easier to use,which made the issue of image tampering far more *** a direct result to the development of sophisticated image-editing applications,it has become near impossible to recognize tampered images with naked ***,to overcome this issue,computer techniques and algorithms have been developed to help with the identification of tampered *** on detection of tampered images still carries great *** the present study,we particularly focus on image splicing forgery,a type of manipulation where a region of an image is transposed onto another *** proposed study consists of four features extraction stages used to extract the important features from suspicious images,namely,Fractal Entropy(FrEp),local binary patterns(LBP),Skewness,and *** main advantage of FrEp is the ability to extract the texture information contained in the input ***,the“support vector machine”(SVm)classification is used to classify images into either spliced or *** analysis shows that the proposed algorithm performs better than recent state-of-the-art of splicing detection ***,the proposed algorithm achieves an ideal balance between performance,accuracy,and efficacy,which makes it suitable for real-world applications.

关键词： Fractal entropy image splicing texture features LBP SVm

Application of artificial neural networks to predict the COVID-19 outbreak

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Global Health Research and Policy 2020年第1期5卷 56-66页

作者： hamid Reza Niazkar majid Niazkar Gonabad University of medical Sciences GonabadIran Department of Civil and Environmental Engineering Shiraz UniversityShirazIran

Background:millions of people have been infected worldwide in the COVID-19 *** this study,we aim to propose fourteen prediction models based on artificial neural networks(ANN)to predict the COVID-19 outbreak for policy ***:The ANN-based models were utilized to estimate the confirmed cases of COVID-19 in China,Japan,Singapore,Iran,Italy,South Africa and United States of *** models exploit historical records of confirmed cases,while their main difference is the number of days that they assume to have impact on the estimation *** COVID-19 data were divided into a train part and a test *** former was used to train the ANN models,while the latter was utilized to compare the *** data analysis shows not only significant fluctuations in the daily confirmed cases but also different ranges of total confirmed cases observed in the time interval ***:Based on the obtained results,the ANN-based model that takes into account the previous 14 days outperforms the other *** comparison reveals the importance of considering the maximum incubation period in predicting the COVID-19 *** the ranges of determination coefficients indicates that the estimated results for Italy are the best ***,the predicted results for Iran achieved the ranges of[0.09,0.15]and[0.21,0.36]for the mean absolute relative errors and normalized root mean square errors,respectively,which were the best ranges obtained for these criteria among different ***:Based on the achieved results,the ANN-based model that takes into account the previous fourteen days for prediction is suggested to predict daily confirmed cases,particularly in countries that have experienced the first peak of the COVID-19 *** study has not only proved the applicability of ANN-based model for prediction of the COVID-19 outbreak,but also showed that considering incubation period of SARS-COV-2 in prediction models may generate m

关键词： COVID-19 outbreak SARS-COV-2 Prediction model Artificial neural network Artificial intelligence Estimation model

Soil loss and displacement by heavy equipment in forest road subgrading projects

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International Journal of Sediment Research 2009年第2期24卷 227-235页

作者： Aidin PARSAKHOO Seyed Ataollah HOSSEINI majid LOTFALIAN hamid JALILVAND m.Sc. Student of Forest Engineering Faculty of Natural ResourcesMazandaran University Department of Forestry Faculty of Natural ResourcesMazandaran University

Forest soil is an important component of the natural environment,and is a primary medium for many biological activities. In this study,soil loss and displacement by excavator and bulldozer(heavy equipments) were measured on cut and fills slopes of forest roads located in mazandaran province,Iran. The volumes of soil losses were estimated by prismoidal analyses of cut and fill slopes deformation between two time treatments(under subgrading and two years later) in slope classes of 30-50% and 50-70%. Weights of soil losses were calculated by multiplying the volumes of soil losses(cm3) to the general bulk density(1.3g/cm3) . Soil displaced area by heavy equipment was evaluated according to earth working width. Results indicated that heavy equipment has significant effect on deformation of cut slope gradient and fill slope length(pmed in different slope classes. The average soil loss by excavator and bulldozer were 160.35 t/ha·yr and 429.09 t/ha·yr,respectively. moreover,the soil displaced area during the subgrading process by bulldozer was greater than excavator in both two slope classes(pment in forest roads can be reduced by applying powerful excavators in subgrading project,especially in steep terrains.

关键词： Soil losses Soil displacement Heavy equipment Forest road Subgrading