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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 f 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

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

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

Behavior Analysis of Biomimetic Soft Bending Actuators in free Motion and Contact

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Journal of Bionic Engineering 2023年第3期20卷 967-981页

作者： Mohammad hadi Namdar Ghalati Sepideh Akbari Hamed Ghafarirad Mohammad Zareinejad Department of Mechanical Engineering Amirkabir University of TechnologyTehran***Iran New Technologies Research Center(NTRC) Amirkabir University of TechnologyTehran***Iran

Bioinspired Soft Bending Actuators (SBA) are increasingly being used in rehabilitation, assistant robots, and grippers. Despite many investigations on free motion modeling, understanding how these actuators interact with the environment requires more detailed research. It is caused by high compliance and nonlinearity of bioinspired soft material, which leads to serious challenges in contact conditions. In this paper, a continuous deformation analysis is presented to describe the free motion nonlinear behavior of the actuator. Based on the achieved result, this study proposes static modeling of SBA affected by a concentrated external force. for this purpose, the finite rigid element method is utilized, which is based on discretizing the actuator into smaller parts and assuming these parts as rigid serial links connected by nonlinear torsional springs. To verify the proposed model, two kinds of forces are considered to be acting on the actuator, i.e. following force and constant direction force. In addition, the effect of gravity on the actuator configuration is also investigated. The validity of the model has been demonstrated through experiments in free motion, contact conditions and the presence of gravity. It generally shows that the prediction error of robot configuration is lower than 7.5%.

关键词： Biomimetic soft bending actuator Static modeling Contact force constraints Rigid finite element

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

A newly designed BIPV system with enhanced passive cooling and ventilation

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Building Simulation 2023年第11期16卷 2093-2107页

作者： hadi Ahmadi Moghaddam Svetlana Tkachenko Guan Heng Yeoh Victoria Timchenko School of Mechanical and Manufacturing Engineering University of New South WalesSydneyNSW2052Australia

Nowadays,the application of renewable energies such as solar energy in the building sector has increased notably considering the adverse impacts of climate change on human life;hence many studies have focused on the application of photovoltaic panels in *** the current study,a 3D computational fluid dynamics(CfD)model has been developed to evaluate the performance of a newly designed building-integrated photovoltaic(BIPV)*** the negative influence of overheating on the lifespan and performance of PV panels,their passive air cooling has been ***,the potential of rooftop-mounted solar panels in passive ventilation of buildings by generating natural convective currents has been *** developed CfD model takes into consideration the effects of radiation,conduction,and buoyancy-driven natural convective currents generated by solar PV panels which are heated due to the exposure to solar radiation heat *** results suggest that applying a high surface emissivity for the part of the roof beneath the PV panels intensifies the natural convective currents which in turn provides better cooling for PV panels with higher cooling effects at higher solar heat *** to a 34%increase in the convective mass flow rate and a 3 K decrease in the mean temperature of the panels were attained by modifying the emissivity of roof *** a 3 K decrease in the operating temperature of the PV panels can enhance their efficiency and lifespan by about 1.56%and 21%,*** on the operating conditions and system characteristics,the BIPV system yielded an air change rate(ACH)in the range of 3-13 which was considered to be highly prevalent in providing the required passive ventilation for a wide range of *** was also observed that the flow dynamics inside the building were affected by both the amount of solar heat load incident on the solar panels and the emissivity of the roof surface behind the panels.

关键词： air change rate BIPV natural convection passive cooling passive ventilation surface emissivity

frequencies Rotation at High Sound Pressure Levels Toward Low frequencies

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Sound & Vibration 2020年第4期54卷 237-246页

作者： hadi Negahdari Sirus Javadpour faramarz Moattar Department of Environmental Engineering Faculty of Natural Resources and EnvironmentScience and Research BranchIslamic Azad UniversityTehranIran Materials Science and Engineering Department School of EngineeringShiraz UniversityShirazIran

Today,analyzing of sound pressure level and frequency is considered as an important index in human *** experts believe that analyzing of these parameters can help us to better understanding of work *** measurements and frequency analysis did to fix the harmful frequency in all sections in Shiraz gas power plant with sound analyzer model BSWA *** sound pressure levels(LP)and the one and one-third octave band were continuously measured in A and C weighting networks and slow mode for time *** 2013 and Minitab 18.1 software used for statistical *** analyzed by Minitab 18.1 *** highest harmful frequency in Shiraz Gas Power Plant(SGPP)was 50 Hz with 115 *** sound pressure level(SPL)ranged from 45 dB to 120 dB in one-third octave band and weighting network *** maximum sound pressure level was in Craft electricity generator with 105.3 dB and 67 *** pressure level in surrounded environment was 120 *** to the results,in this industry the sound pressure level exceeded the Occupational Exposure Level of Iran(OEL).The value of sound pressure level were higher than the Standard of occupational *** consumes 47000 cubic meters of natural gas per hour to produce 100 MW(Mega Watt)of *** is very high and it is not economical and cost *** numbers indicate that the power plant’s efficiency is *** could be concluded that the noise pollution is an important issue in these ***,SGPP produce noise with loss *** rotation at high sound pressure levels toward low frequencies were happened.

关键词： Sound waves noise-induced occupational safety industrial health noise

Reaction pathway and kinetics of CdO nanoparticles prepared from CdCO_3 precursor using thermal decomposition method

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Transactions of Nonferrous Metals Society of China 2016年第4期26卷 1138-1145页

作者： Gholam Reza KHAYATI Seyed hadi SHAHCHERAGHI Vahid LOTfI Esmael DAREZARESHKI Department of Materials Science and Engineering Shahid Bahonar University of KermanP.O.Box No.76135-133KermanIran Department of Advanced Science and Technology Shahid Bahonar University of KermanP.O.Box No.76135-133KermanIran Mineral Industries Research Centre Shahid Bahonar University of KermanP.O.Box No.76135-133KermanIran

The non-isothermal kinetics of CdO nanoparticles prepared from CdCO3 precursor using thermal decomposition method was investigated. A model-fitting Malek approach and a model-free advanced isoconversional method of Vyazovkin were applied to the analysis of the DSC and TGA data. The results showed that CdO nanoparticles prepared from CdCO3 followed an autocatalytic reaction. Sestak–Berggren model could favorably describe the studied reaction process. Moreover, the apparent activation energy of CdCO3 decomposition was calculated to be (119.19±9.97) kJ/mol and the explicit rate equation form of CdCO3 decomposition was established.

关键词： CdCO_3 CdO nanoparticle kinetic modeling thermal decomposition advanced isoconversional method