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Kinetics and mechanism of titanium hydride powder and aluminum melt reaction

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 165-172页

作者： Ali Rasooli Mehdi Divandari hamid reza Shahverdi Mohammad Ali Boutorabi School of Metallurgy and Materials Engineering Member of Center of Excellence for Advanced Material and Processing (CEAMP) Iran University of Science and Technology Tehran 16844 Iran Department of Materials Faculty of Engineering Tarbiat Modaress University Tehran 14115-143 Iran

Based on the measurement of the released hydrogen gas pressure （PH2）, the reaction kinetics between TiH2 powder and pure aluminum melt was studied at various temperatures. After cooling the samples, the interface of TiH2 powder and aluminum melt was studied. The results show that the-time curves have three regions; in the first and second regions, the rate of reaction conforms zero and one order, respectively; in the third region, the hydrogen gas pressure remains constant and the rate of reaction reaches zero. The main factors that control the rate of reaction in the first and second regions are the penetration of hydrogen atoms in the titanium lattice and the chemical reaction between molten aluminum and titanium, respectively. According to the main factors that control the rate of reaction, three temperature ranges are considered for the reaction mechanism：（a） 700-750°C, （b） 750-800°C, and （c） 800-1000°C. In the first temperature range, the reaction is mostly under the control of chemical reaction; at the temperature range of 750 to 800°C, the reaction is controlled by the diffusion and chemical reaction; at the third temperature range （800-1000°C）, the dominant controlling mechanism is diffusion.

关键词： titanium hydride aluminum reaction kinetics reaction rate constants

Field evaluation of durum wheat landraces for prevailing abiotic and biotic stresses in highland rainfed regions of Iran

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The Crop Journal 2015年第5期3卷 423-433页

作者： reza mohammadi Behzad Sadeghzadeh Hasan Ahmadi Nowzar Bahrami Ahmed Amri Dryland Agricultural Research Institute (DARI) Center of Agricultural Research and Natural Resources International Center for Agricultural Research in the Dry Areas (ICARDA)

Biotic and abiotic stresses are major limiting factors for high crop productivity worldwide. A landrace collection consisting of 380 durum wheat(Triticum turgidum L. var. durum) entries originating in several countries along with four check varieties were evaluated for biotic stresses:yellow rust(Puccinia striiformis Westendorf f. sp. tritici) and wheat stem sawfly(WSS) Cephus cinctus Norton(Hymenoptera: Cephidae), and abiotic stresses: cold and drought. The main objectives were to(i) quantify phenotypic diversity and identify variation in the durum wheat landraces for the different stresses and(ii) characterize the agronomic profiles of landraces in reaction to the stresses. Significant changes in reactions of landraces to stresses were *** resistant to each stress were identified and agronomically *** reduction due to the stresses varied from 11.4%(yellow rust) to 21.6%(cold stress) for 1000-kernel weight(TKW) and from 19.9(yellow rust) to 91.9%(cold stress) for grain yield. Landraces from Asia and Europe showed enhanced genetic potential for both grain yield and cold tolerance under highland rainfed conditions of Iran. The findings showed that TKW and yield productivity could be used to assess the response of durum wheat landraces to different stresses. In conclusion, landraces showed high levels of resistance to both biotic and abiotic stresses, and selected landraces can serve in durum wheat breeding for adaptation to cold and drought-prone environments.

关键词： Durum wheat Landraces Biotic and abiotic stresses

Multi-scale analysis of flow structures in fluidized beds with immersed tubes

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Particuology 2015年第4期13卷 99-106页

作者： hamid R.Norouzi Maryam Tahmasebpoor reza Zarghami Navid Mostoufi Multiphase Systems Research Lab.School of Chemical Engineering College of EngineeringUniversity of Tehran Department of Chemical and Petroleum Engineering University of Tabriz

Multi-scale analysis and non-linear analysis were combined to investigate the hydrodynamics of fluidized beds with and without horizontal tubes. Pressure fluctuations were measured and analyzed employing discrete wavelet analysis, recurrence plot analysis, and recurrence quantification analysis. A systematic procedure was followed to determine wavelet parameters. At low gas velocities, the energy of macro-structures reduces with the addition of the first tube and then increases with the addition of a second tube. However, there is no notable difference at high gas velocities. Determinism is high for the bed without tubes, which can be attributed to the periodic behavior of bubbles. Determinism decreases with the addition of tubes because the breakage of bubbles results in less periodic behavior. The three methods of analysis used in this study captured the effects of immersed tubes on the hydrodynamics of fluidized beds. Recurrence quantitative analysis was found to be a powerful and easy-to-use method that can capture the nonlinear characteristics of fluidized beds much more quickly than conventional methods of nonlinear analysis. This method can thus be effectively used for the online monitoring of hydrodynamic changes in fluidized beds.

关键词： Immersed tube Non-linear analysis Pressure fluctuations Recurrence plot Wavelet transform

The common road safety approaches:A scoping review and thematic analysis

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Chinese Journal of Traumatology 2020年第2期23卷 113-121页

作者： hamid Safarpour Davoud Khorasani-Zavareh reza mohammadi Department of Health in Emergencies and Disasters School of Public Health and SafetyShahid Beheshti University of Medical SciencesTehranIran Workplace Health Promotion Research Center Shahid Beheshti University of Medical SciencesTehranIran Department of Neurobiology Care Sciences and SocietyH1Division of Family Medicine and Primary CareHuddingeSweden

Purpose:Comparison of effective road safety approaches with those of relatively similar countries can be used to identify possibilities for safety *** there is no clear and comprehensive study of countries'current and successful approaches to road safety in the world,the aim of this study was to identifying common road safety approaches in the ***:This study was performed using scoping review and thematic *** study followed the approach proposed by Arksey and O'*** this study all articles were selected without time limit by searching in the following databases:Web of Science,PubMed,Scopus,ProQuest,and *** initial search of 5612 papers was found and finally,20 papers met the inclusion criteria and were ***:There were different road safety approaches in different countries around the world,which were classified in three themes:traditional approach,systemic approach,and vision *** traditional approach includes the sub-theme of the road-user approach,and the causal *** systemic approach also includes sub-themes of sustainable safety,safety system,and the United Nations plan for decade of action,Conclusion:A systemic approach to road safety seems to be welcomed by most developed and developing countries,and a paradigm shift towards a safe system has taken ***,given the successful results of implementing vision zero in leading countries,most countries are trying to design and implement this ***,the choice and implementation of road safety approaches varies according to the principles,priorities and infrastructure of each country.

关键词： Road safety Vision zero Road traffic injury Road traffic accident Approach Safe system

Effects of chelating agents on the sol-gel synthesis of nano-zirconia:Comparison of the Pechini and sugar-based methods

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 693-702页

作者： Faramarz Kazemi Farzin Arianpour Mahdiar Taheri Ali Saberi hamid reza rezaie Department of Mining and Metallurgy Amirkabir University of TechnologyTehranIran Research and Application Center Kastamonu UniversityKastamonuTurkey College of Engineering and Computer Science The Australian National UniversityCanberraAustralia Materials Processing Faculty of Engineering ScienceUniversity of BayreuthBayreuthGermany School of Metallurgy and Materials Engineering Iran University of Science and TechnologyTehranIran

This study focused on the comparison of the Pechini and sugar-based combustion synthesis methods to produce nano-zirconia. Zirconium hydroxide was utilized as metal precursor and citric acid, sucrose, and fructose were used as chelating agents, followed by calcination at 500, 600, and 700°C in air, respectively. Characterization was conducted by thermal analysis, specific surface area measurement, Fourier transform infrared spectroscopy, X-ray diffraction, and scanning and transmission electron microscopy. When sucrose and citric acid were used as chelating agents during synthesis, mixtures of monoclinic and tetragonal phases were formed after calcination at 600 and 700°C. In the fructose samples, the tetragonal structure was the unique characterized phase. The tetragonal parameters in the fructose samples were determined using the diffraction data and the lattice parameter ratio was proven to increase with the temperature increase. Compared with the citrate and sucrose samples, the largest specific surface area(27 m2·g-1) and smallest particle size(39.1 nm) were obtained for the fructose sample after calcination at 700°C. The study revealed the formation of single-phase stabilized tetragonal zirconia using fructose as chelating agent after calcination at 500°C, and the presence and formation mechanism of stabilized tetragonal phase were also discussed on the basis of the X-ray and electron diffraction studies.

关键词： zirconia nanopowder sol-gel sugar Pechini chelation

Geostatistical Assessment of the Spatial Distribution of Some Chemical Properties in Calcareous Soils

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Journal of Integrative Agriculture 2012年第10期11卷 1729-1737页

作者： Asma Najafian Mahmood Dayani hamid reza Motaghian Habibolah Nadian Department of Soil Sciences College of Agriculture Shiraz University Shiraz *** 1ran Department of Soil Sciences Khouzestan Ramin University of Agriculture and Natural Resources Ahwaz *** Iran Department of Soil Science Faculty of Agriculture Shahrekord University Shahrekord *** Iran

Spatial patterns of soil fertility parameters and other extrinsic factors need to be identified to develop farming practices that match agricultural inputs with local crop needs. Little is known about the spatial structure of nutrition in Iran. The present study was conducted in a 132-ha field located in central Iran. Soil samples were collected at 0-30 cm depth and were then analyzed for total nitrogen （N）, available phosphorus （P）, available potassium （K）, available copper （Cu）, available zinc （Zn）, available iron （Fe） and available manganese （Mn）. The results showed that the contents of soil organic matter, Cu and Zn in Marvdasht＇s farms were low. The spatial distribution model and spatial dependence level for soil chemical properties varied in the field. N, K, carbonate calcium equivalent （CaCO3） and electrical conductivity （EC） data indicated the existence of moderate spatial dependence. The variograms for other variables revealed stronger spatial structure. The results showed a longer range value for available P （480 m）, followed by total N （429 m）. The value of other chemical properties values showed a shorter range （128 to 174 m）. Clear patchy distribution of N, P, K, Fe, Mn, Cu and Zn were found from their spatial distribution maps. This proved that sampling strategy for estimating variability should be adapted to the different soil chemical properties and field management. Therefore, the spatial variability of soil chemical properties with strong spatial dependence could be readily managed and a site-specific fertilization scheme for precision farming could be easily developed.

关键词： geostatistics kriging spatial variability precision farming

Statistical functions used for spatial modelling due to assessment of landslide distribution and landscape-interaction factors in Iran

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Geoscience Frontiers 2020年第4期11卷 1257-1269页

作者： hamid reza Pourghasemi Narges Kariminejad Amiya Gayen Marko Komac Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran Gorgan University of Agricultural Sciences and Natural Resources Dept.of Watershed&Arid Zone ManagementGorganIran Department of Geography University of CalcuttaKolkataIndia Faculty of Civil and Geodetic Engineering University of LjubljanaSlovenia

Landslides influence the capacity for safe and sustainable development of mountainous *** study explores the spatial distribution of and the interactions between landslides that are mapped using global positioning system(GPS) and extensive field surveys in Mazandaran Province,***-pattern assessment is undertaken using several univariate summary statistical functions,including pair correlation,spherical-contact distribution,nearest-neighbor analysis,and O-ring analysis,as well as bivariate summary statistics,and a markcorrelation *** maximum entropy method was applied to prioritize the factors controlling the incidence of landslides and the landslides susceptibility *** validation processes were considered for separated 30%data applying the ROC curves,fourfold plot,and Cohen’s kappa *** results show that pair correlation and O-ring analyses satisfactorily predicted landslides at scales from 1 to 150 *** smaller scales,from 150 to 400 m,landslides were randomly *** nearest-neighbor distribution function show that the highest distance to the nearest landslide occurred in the 355 *** spherical-contact distribution revealed that the patterns were random up to a spatial scale of 80 *** bivariate correlation functions revealed that landslides were positively linked to several linear features(including faults,roads,and rivers) at all spatial *** mark-correlation function showed that aggregated fields of landslides were positively correlated with measures of land use,lithology,drainage density,plan curvature,and aspect,when the numbers of landslides in the groups were greater than the overall average *** results of analysis of factor importance have showed that elevation(topography map scale:1:25,000),distance to roads,and distance to rivers are the most important factors in the occurrence of *** susceptibility model of landslides indicates an excellent accuracy,i.e.,the AUC value of lands

关键词： Landslide Spatial point pattern Summary statistic GIS Iran

COVID-19 international outbreak and the need for a suitable estimation model: A second-order polynomial equation with constant coefficients based on imported infected cases seems inadequate

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Asian Pacific Journal of Tropical Medicine 2020年第4期13卷 185-186页

作者： hamid reza Niazkar Majid Niazkar Student Research Committee Gonabad University of Medical SciencesGonabadIran Department of Civil and Environmental Engineering Shiraz UniversityShirazIran

COVID-19 due to infections with the 2019 novel coronavirus(SARS-CoV-2)was first reported in Wuhan,Hubei Province,China in December *** to 2 March 2020,it has already spread to more than 55 countries,infected more than 85000 individuals,and yielded to about 3000 death cases[1].Due to the vigorous outbreak of COVID-19,it has become a global *** management and controlling of this worldwide threat inevitably relies on the preparedness and precise risk assessment of the future,particularly in countries that new cases have been *** this regard,estimation of new probable confirmed and death cases in the near future is crucial to health care systems of each *** a result,some researches have been conducted to address this new concern[2-4].

关键词： estimation cases precise

NEW APPROACH TO EMULATE SEU FAULTS ON SRAM BASED FPGAS

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Journal of Electronics(China) 2014年第1期31卷 68-77页

作者： reza Omidi Gosheblagh Karim mohammadi Department of Electrical Engineering Iran University of Science and Technology (IUST)

Field Programmable Gate Arrays(FPGAs)offer high capability in implementing of complex systems,and currently are an attractive solution for space system ***,FPGAs are susceptible to radiation induced Single-Event Upsets(SEUs).To insure reliable operation of FPGA based systems in a harsh radiation environment,various SEU mitigation techniques have been *** this paper we propose a system based on dynamic partial reconfiguration capability of the modern devices to evaluate the SEU fault effect in *** proposed approach combines the fault injection controller with the host FPGA,and therefore the hardware complexity is *** of the SEU injection and evaluation requirements are performed by a soft-core which realized inside the host *** results on some standard benchmark circuits reveal that the proposed system is able to speed up the fault injection campaign 50 times in compared to conventional method.

关键词： Field Programmable Gate Arrays(FPGAs) Single-Event Upset(SEU) fault injection Soft-core Space radiation effects