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Journal of University of Science and Technology Beijing 2006年第2期13卷 97-101页

作者： A. hadi Ozdeniz Cem Sensogut Mining Engineering Department Selcuk University 42079 Konya Turkey Mining Engineering Department Dumlupinar University 43100 Kutahya Turkey

The spontaneous combustion event in coal stockpiles is inevitable when appropriate environmental conditions are available. The objective of a computerized measurement system is to measure temperature changes existing in a coal stockpile. In order to achieve this intention, the electrical signal conversion of temperatures sensed by 20 temperature sensors placed in certain points inside the coal stockpile, the transfer of these electrical signals into computer media by using analogue-digital conversion unit after applying necessary filterization and upgrading processes and the record of these information into a database in particular time intervals are provided. Afterwards, the diagrams of these time-temperature data are plotted. With the help of these graphs, the competent company will be able to examine the behavior of coal stockpiles in terms of spontaneous combustion and take necessary precautions against self-combustion beforehand.

关键词： spontaneous combustion coal stockpile Western Lignite Corporation resistance temperature detector

A constitutive model for evaluation of mechanical behavior of fiber-reinforced cemented sand

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第2期11卷 349-360页

作者： hadi Abioghli Amir Hamidi Department of Civil Engineering School of EngineeringKharazmi University

The aim of this study is to present a constitutive model for prediction of the mechanical behavior of fiberreinforced cemented sand. For this purpose, a generalized plasticity constitutive model of sandy soil is selected and the parameters of the model are determined for three types of sandy soils using the results of triaxial tests. Next, the proposed model is developed using the existing models based on the physicomechanical characteristics of fiber-reinforced cemented sand. The elastic parameters, flow rule and hardening law of the base model are modified for fiber-reinforced cemented sand. To verify the proposed model, the predicted results are compared with those of triaxial tests performed on fiber-reinforced cemented sand. Finally, the efficiency of the proposed model is studied at different confining pressures, and cement and fiber contents.

关键词： Fiber-reinforced cemented sand Constitutive model Hardening law Flow rule

High photocatalytic efficiency of spouting reactor compared with fluidized bed with top irradiation source

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Particuology 2017年第4期15卷 123-128页

作者： hadi Mansoubi Zahra Mansourpour Shohreh Fatemi School of Chemical Engineering College of Engineering University of Tehran Tehran lran

The removal of volatile organic compounds by photocatalytic degradation is one of the safest and most effective ways of removing pollutants from the air. This process is highly affected by the type of reactor, light exposure, and hydrodynamics. For scale up purposes, continuous reactors with high capacity are required for treating large amounts of feedstock. In this work, two types of reactors based on different hydrodynamics, fluidized and spouted reactors, were designed to work under light irradiation inside the reactor. The efficiency of the reactors for volatile organic compound removal from high flow rates of air under Hg lamp irradiation using N-F-TiO2 photocatalyst was investigated. The performance of the fluidized bed and spouted bed were evaluated and compared at the same weight hourly space velocity of feed stream through the reactor. The results revealed that 80% of the initial acetaldehyde was removed in the fluidized bed after about 200 min, while in the spouted bed the acetaldehyde was totally removed after about 120 min.

关键词： Spouted bed reactor Photocatalyst powder VOC removal High efficiency Fluidized bed reactor N-F TiO2

Configuration Reusing in On-Line Task Scheduling for Reconfigurable Computing Systems

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Journal of Computer Science & Technology 2011年第3期26卷 463-473页

作者： Maisam Mansub Bassiri hadi Shahriar Shahhoseini Electrical Engineering Department Iran University of Science and Technology

Reconfigurable computing systems can be reconfigured at runtime and support partial reconfigurability which makes us able to execute tasks in a true multitasking manner. To manage such systems at runtime, a reconfigurable operating system is needed. The main part of this operating system is resource management unit which performs on-line scheduling and placement of hardware tasks at runtime. Reconfiguration overhead is an important obstacle that limits the performance of on-line scheduling algorithms in reconfigurable computing systems and increases the overall execution time. Configuration reusing （task reusing） can decrease reconfiguration overhead considerably, particularly in periodic applications or the applications in which the probability of tasks recurrence is high. In this paper, we present a technique called reusing-based scheduling （RBS）, for on-line scheduling and placement in which configuration reusing is considered as a main characteristic in order to reduce reconfiguration overhead and decrease total execution time of the tasks. Several experiments have been conducted on the proposed algorithm. Obtained results show considerable improvement in overall execution time of the tasks.

关键词： reconfigurable computing on-line scheduling configuration reusing RPU partitioning replacement manage-ment probability of recurrence

Parametric study on the mixed solvent synthesis of ZIF-8 nano- and micro-particles for CO adsorption: A response surface study

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 579-594页

作者： Alireza hadi Javad Karimi-Sabet Abolfazl Dastbaz Department of Chemical Engineering Faculty of EngineeringUniversity of TehranTehranIran Material and Nuclear Fuel Research School(MNFRS) Nuclear Science and Technology Research InstituteTehranIran

The room temperature synthesis of ZIF-8 micro-and nano-particles was investigated using a mixed methanol-water solvent ***-8 particles of good quality and high crystallinity were *** surface methodology was used to determine the effect of the synthesis conditions on the ZIF-8 yield,particle size distribution,and mean particle *** ligand/metal salt molar ratio followed by the amount of sodium formate(the deprotonating agent)and then the amount of water(i.e,the composition of the mixed solvent)respectively had the largest effects on both the ZIF-8 yield and particle *** showed that mixing of solvents with different strengths in producing ZIF-8 crystals is a practical method to size-controlled synthesis of ZIF-8 *** method is more favorable for industrial-scale ZIF-8 synthesis than using excess amounts of ligands or chemical additives(like sodium formate).In addition,ZIF-8 samples with different mean particle sizes(100,500,and 1000 nm)were used for CO adsorption and the mid-sized ZIF-8 particles had the highest adsorption capacity.

关键词： metal organic frameworks zeolitic imidazo-late frameworks ZIF-8 response surface methodology Box Behnken design CO adsorption

Determination of trace amounts of silver(I) in the presence of an activator with a kinetic method

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Rare Metals 2014年第6期33卷 731-736页

作者： Shahryar Abbasi hadi Barzegaramiri Abbas Farmany Department of Chemistry Ilam University Department of Chemistry Islamic Azad University

A simple and sensitive kinetic-spectrophotometric method was developed for the determination of trace amounts of silver, based on its catalytic effect on the oxidation of azocarmine G by peroxydisulfate in sulfuric acid medium and at 30 °C in the presence of 1,10-phenantroline as activator. The absorbance was measured at 525 nm with the fixed-time method. The optimization of the operating conditions regarding concentrations of the reagents, temperature, ionic strength, and interferences was also investigated. The calibration curve is linear over the concentration range 0.3–50.0 ng ml-1of silver with good precision and accuracy, and the detection limit is down to0.125 ng ml-1. The relative standard deviation for a standard solution of 25.0 ng ml-1of silver is 1.36 %（n = 10）.The proposed method proves to be highly sensitive,selective, and relatively rapid for the assay of silver at lowlevel range of 0.3–50.0 ng ml-1without any pre-concentration and separation step. The method was applied for the determination of silver in river water and white photographic film. The analytic results of the real samples are in excellent agreement with atomic absorption spectrometry analysis. The analytical results obtained are satisfactory.

关键词： Silver Kinetic-catalytic determination Azocarmine G Activator 1,10-Phenantroline

Future meteorological drought conditions in southwestern Iran based on the NEX-GDDP climate dataset

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Journal of Arid Land 2023年第4期15卷 377-392页

作者： Sakine KOOHI hadi RAMEZANI ETEDALI Department of Water Engineering Faculty of Agriculture and Natural ResourcesImam Khomeini International UniversityQazvin 96818Iran

Investigation of the climate change effects on drought is required to develop management strategies for minimizing adverse social and economic ***,studying the future meteorological drought conditions at a local scale is *** this study,we assessed the efficiency of seven downscaled Global Climate Models(GCMs)provided by the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP),and investigated the impacts of climate change on future meteorological drought using Standard Precipitation Index(SPI)in the Karoun River Basin(KRB)of southwestern Iran under two Representative Concentration Pathway(RCP)emission scenarios,i.e.,RCP4.5 and *** results demonstrated that SPI estimated based on the Meteorological Research Institute Coupled Global Climate Model version 3(MRI-CGCM3)is consistent with the one estimated by synoptic stations during the historical period(1990-2005).The root mean square error(RMSE)value is less than 0.75 in 77%of the synoptic *** have high uncertainty in most synoptic stations except those located in the *** the average of a few GCMs to improve performance and reduce uncertainty is suggested by the *** results revealed that with the areas affected by wetness decreasing in the KRB,drought frequency in the North KRB is likely to increase at the end of the 21st century under RCP4.5 and RCP8.5 *** the seasonal scale,the decreasing trend for SPI in spring,summer,and winter shows a drought tendency in this *** climate-induced drought hazard can have vast consequences,especially in agriculture and rural ***,an increasing trend in drought during the growing seasons under RCP scenarios is vital for water managers and farmers to adopt strategies to reduce the *** results of this study are of great value for formulating sustainable water resources management plans affected by climate change.

关键词： climate change meteorological drought Global Climate Models(GCMs) Standard Precipitation Index(SPI) Representative Concentration Pathway(RCP) NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP) southwestern Iran

Rashba Effect in Presence of Time-Dependent Interaction

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Communications in Theoretical Physics 2016年第5期65卷 543-545页

作者： hadi Sobhani Hassan Hassanabadi Physics Department Shahrood University of TechnologyShahroodIran

Rashba effect in presence of a time-dependent interaction has been *** time-evolution of such a system has been studied by using Lewis–Riesenfeld dynamical invariant and unitary transformation *** appropriate dynamical invariant and unitary transformation according the considered system have been constructed as well as some special cases have come into this article which are common in physics.

关键词： Rashba effect time-dependent interaction Lewis–Riesenfeld dynamical invariant unitary transformation method

Preferential solvation of pomalidomide,an anticancer compound,in some binary mixed solvents at 298.15 K

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2626-2633页

作者： Mohsen Padervand Shima Naseri hadi Chahiyan Boroujeni Department of Chemistry Faculty of ScienceUniversity of MaraghehMaraghehIran Department of Chemistry and Biology Farhangian Teacher Training UniversityMashhad BranchMashhadIran

Preferential solvation of pomalidomide(PMD)was explored in dimethyl sulfoxide(DMSO)-dimethylformamide(DMF),DMSO-tetrahydrofuran(THF),DMSO-methanol(Me OH),DMSO-isopropanol,DMSO-water,water-DMF,water-THF,water-Me OH,and water–isopropanol binary mixed solvents at 298.15 ***-Rose model was utilized to determine the electronic transition energies(ET)and other preferential solvation parameters,describing solute-solute and solute-solvent *** found thatλmaxsituation shifted with dielectric constant of the pure solvents *** to the obtained results,ETenhanced andλmaxshifted to the lower wavelengths as the percentage of DMSO decreased in the binary mixtures,remarking the important role of DMSO for stabilizing the excited state(π*)of PMD chromophore via efficient intermolecular solute-solvent *** addition,the aqueous binary systems showed an optimum point for the ETvalues as the percentage of water changed in the *** local mole fraction of the solvents in the cybotactic region was also estimated to describe the specific and non-specific interactions in the systems.

关键词： Pomalidomide Preferential solvation Bosch-Rose model Binary solvents

Contact Stress Distribution of a Pear Cam Profile with Roller Follower Mechanism

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Chinese Journal of Mechanical Engineering 2021年第1期34卷 266-279页

作者： Louay S.Yousuf Nabil Hassan hadi Department of Mechanical Engineering San Diego State University5500 Campanile DriveSan DiegoCA 92182-1323USA Aeron autical Fngineering Department College of FngineeringUniversity of BaghdadBaghdadIraq

The problem of this paper is the high contact stress at the point of contact between the cam and the follower.A pear cam and roller follower mechanism were studied and analyzed for different position of the follower and different contact compression *** objective of this paper is to study the effect of contact compression load on the contact stress distribution of the cam profile at the point of *** different positions of the follower with the cam was considered(0°,90°,180°,and 270°).The theory of circular plate was applied to derive the analytic solution of the contact *** numerical simulation had been done using ANSYS Ver.19.2 package to determine the contact stress,while SolidWorks software was used to investigate follower displacement,velocity,and *** distinct values of the compression contact load,such as 3.121 N,6.242 N,9.364 N,and 12.485 N,were used in the numerical *** the experiment setup,a photo-elastic technique was carried out in the field of polarized light to exhibit the stress distribution on the cam *** annealed PSM-4 backalate material was used in the experiment *** experimental value of contact stress was checked and verified analytically and numerically at the point of *** innovation in this paper the use of spring-damper system which reduce the value of contact stress at the point of *** contact stress was maximum 2.136 MPa when the follower located at 270°with the cam,while the contact stress was minimum 1.802 MPa when the follower located at 180°at compression load 12.485 N.

关键词： Contact stress Compression load Bending deflection Photo-elastic technique Finite element analysis