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Evaluation of sediment yield in PSIAC and MPSIAC models by using GIS at Toroq Watershed, Northeast of Iran

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Frontiers of Earth Science 2012年第1期6卷 83-94页

作者： mohammad Reza Mansouri Daneshvar ali Bagherzadeh Department of Geography Mashhad Branch Islamic Azad University Mashhad Iran Department of Agriculture Mashhad Branch Islamic Azad University Mashhad Iran

Regarding the importance of watersheds in arid and semi-arid regions, it is necessary to better protect water supplies such as dam reservoirs. The most efficient way of conserving water sources is to apply proper management to decrease erosion and sedimentation. The first step of this process is to be aware of sediment yield （Qs）/production and identify erosive zones in upper reach of reservoirs. The present study aims to evaluate Qs and production in Pacific Southwest Inter-Agency Committee （PSIAC） and mod- ified PSIAC （MPSIAC） models by using satellite data, GIS analysis, and field observations. According to the results, the study area can be categorized into five erosive classes： very high, high, moderate, low and negligible. The east part of the watershed is slightly eroded due to its hard surface geology and relatively flat topography characteristics, while the northern and southern parts of the basin are highly eroded because of the high erodibility potential of soil and intensive cultivation of the area. A comparison of the output maps from PSIAC and MPSIAC models showed that the calculated Qs in most parts correspond well in both models and with field observa- tions. The results of regression between main determining factors （surface geology, soil, topography and land cover） and Qs derived from each model indicated moderate to strong correlation coefficient （R2 = 0.436-0.996 to 0.893- 0.998） after PSIAC and MPSIAC models, respec- tively.

关键词： evaluation of sediment yield (Qs) erodiblefactors Pacific Southwest Inter-Agency Committee(PSIAC) and modified PSIAC (MPSIAC) models sedimentproduction GIS Toroq Watershed Northeast of Iran

Tree-Temperature Monitoring for Frost Protection of Orchards in Semi-Arid Regions Using Sprinkler Irrigation

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Agricultural Sciences in China 2009年第1期8卷 98-107页

作者： ali Asghar Ghaemi mohammad Rafie Rafiee ali Reza Sepaskhah Irrigation Department College of AgricultureShiraz University

Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran （a 0.17 ha peach orchard and a 0.24 ha orange orchard） to protect peach blossoms and orange trees leaves and fruits from low temperature damage. The experiment used a system that monitored the trees and air temperatures using two thermistors. The water application rate by the irrigation system was determined by an energy balance as implemented by the software FROSTPRO, In the peach orchard, the system was tested during three frost events during the spring of 2003 and three other events during the spring of 2004. The system successfully kept peach flowers above the critical temperature, i.e., -4.0℃ in spring 2004 （control block -4.12℃, and sprinkled block ＋0.5℃） during all events. Similar results were obtained in the orange orchard during three frost events in the winter of 2004, during which the tree temperatures were at least 2.5℃ above the critical temperature. Results from field tests show that the system can effectively protect the peach blossoms from damage. Determination done after the frost events showed a 12% blossom kill in the sprinkled blocks while in the unsprinkled control block a 41.5% blossom kill. Calculations indicated that when using variable application rates, the amount of water used can be reduced by 54.3%. Spatial distribution of minimum temperatures during the three frosts was also studied in Jahrom, Iran. Results showed a significant temperature control in the experimental block, especially in the central part of the orchard, but the block margins （about 3.6% of the total area） were at the risk of low temperature due to the wind drift effects.

关键词： automated sprinkler irrigation FROSTPORO frost protection peach orchard orange orchard

A Sensitive Simultaneous Determination of Adrenalin and Paracetamol on a Glassy Carbon Electrode Coated with a Film of Chitosan/Room Temperature Ionic Liquid/Single-Walled Carbon Nanotubes Nanocomposite

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Chinese Journal of Chemistry 2011年第10期29卷 2157-2164页

作者： Babaei, ali Babazadeh, Mitra Afrasiabi, mohammad Department of Chemistry Faculty of Science Arak University Arak 38156-8-8349 Iran Research Center for Nanotechnology University of Arak P.O. Box 38156-879Iran Young Researchers Club Shoushtar Branch Islamic Azad University Shoushtar Iran

The present work demonstrates that simultaneous determination of adrenalin （AD） and paracetamol （PAR） can be performed on single-walled carbon nanotube/chitosan/ionic liquid modified glassy carbon electrode （SWCNT-CHIT-IL/GCE）. The electro-oxidations of AD and PAR were investigated with cyclic voltammetry （CV）, differential pulse voltammetry （DPV） and also chronoamperometry （CA） methods. DPV experiments showed that the oxidation peak currents of AD and PAR are proportional to the corresponding concentrations over the 1-580 μmol/L and 0.5-400 μmol/L ranges, respectively. The RSD at a concentration level of 15 μmol/L AD and 15 μmol/L PAR were 1.69% and 1.82%, respectively. Finally the modified electrode was used for simultaneous determination of AD and PAR in real samples with satisfactory results.

关键词： modified electrode ionic liquid adrenalin paracetamol single-wailed carbon nanotubes

An analytical solution for spherical fluid flow modeling in porous media with non-uniform initial pressure considering the supercharging effect

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Petroleum 2021年第3期7卷 303-313页

作者： ali Nabizadeh mohammad Sharifi Babak Aminshahidi Institute of GeoEnergy Engineering School of EnergyGeoscienceInfrastructure and SocietyHeriot-Watt UniversityEdinburghUK Department of Petroleum Engineering Amirkabir University of Technology(Tehran Polytechnic)P.O.Box:15875-4413TehranIran

The diffusivity equation is a partial differential equation(PDE)which can be used for fluid flow modeling in porous *** reservoir parameters from pressure data(i.e.,pressure transient analysis)is one of the most important steps in the process of field *** initial evaluation can be used to make decisions about future *** Formation Testing(WFT)is one of the most popular techniques for parameter estimation and has received significant attention in recent *** main problem plaguing WFT is a phenomenon known as the“supercharging effect,”which essentially refers to mud invasion,and this,in turn,alters pressure distribution across the *** this study,an analytical solution for fluid flow modeling in spherical coordinates with non-uniform initial pressure is *** new procedure takes into account the effect of mud invasion,or,in other words,the supercharging *** accuracy of this derivation was validated using previous semianalytical solutions(the Laplace method)in addition to field *** type curves and dimensionless parameters,which can be used for pressure transient analysis,are also *** procedure is applied to the WFT data that was obtained from an oil field in the south of Iran,and an excellent agreement(less than 10%error)was *** addition,there is considerable uncertainty regarding the radius of investigation for spherical *** is important as this parameter greatly affects the applicability of *** analytical derivation of this study was used to determine a reasonable value for this parameter as well.

关键词： Porous media Analytical solution Supercharging effect Welltesting Spherical Darcy's flow

Electrochemical determination of vitamin C in the presence of uric acid by a novel TiO_2 nanoparticles modified carbon paste electrode

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Chinese Chemical Letters 2010年第12期21卷 1471-1474页

作者： mohammad Mazloum-Ardakani mohammad ali Sheikh-Mohseni Hadi Beitollahi ali Benvidi Hossein Naeimi Department of Chemistry Faculty of ScienceYazd UniversityYazd89195-741I.R.Iran Department of Organic Chemistry Faculty of ChemistryUniversity of KashanKashanI.R.Iran

The electrochemical behavior of vitamin C（ascorbic acid or AA） is investigated on the surface of a carbon-paste electrode modified with TiO2 nanoparticles and 2,2＇-（1,2 butanediylbis（nitriloethylidyne））-bis-hydroquinone（BBNBH）.The prepared modified electrode showed an efficient catalytic role in the electrochemical oxidation of AA,leading to remarkable decrease in oxidation overpotential and enhancement of the kinetics of the electrode *** modified electrode exhibits well-separated oxidation peaks for AA and uric acid（UA）.The modified electrode is successfully applied for the accurate determination of AA in pharmaceutical preparations.

关键词： Ascorbic acid Uric acid TiO2 nanoparticles Electrocatalysis Modified carbon paste electrode

Carpet Cloak Design for Rough Surfaces

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Chinese Physics Letters 2017年第8期34卷 46-50页

作者： mohammad Hosein Fakheri Hooman Barati ali Abdolali Applied Electromagnetic Laboratory School of Electrical Engineering Iran University of Science and Technology Tehran *** Iran

Conventional carpet cloak structures have been utilized to conceal the objects located on a planar perfect electric conductor surface. We systematically investigate hiding arbitrarily shaped objects on a rough surface, as a more general and practical scenario. In addition, the required cloak is designed considering different boundary conditions for the surface beneath the object, despite the previous studies. To achieve an invisibility cloak, taking advantage of linear coordinate transformation, a simple homogeneous material is obtained to realize the cloak structure, facilitating the fabrication processes. Numerical simulations validate the performance of the proposed cloaking method. Therefore, the proposed structure is capable of cloaking in more general and complicated scenarios.

关键词： Carpet Cloak Design for Rough Surfaces

A GIS-based time-dependent seismic source modeling of Northern Iran

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 33-45页

作者： Mahdi Hashemi ali Asghar Alesheikh mohammad Reza Zolfaghari School of Information Seiences University of Pittsburgh Pittsburgh Pennsylvania 15260 USA Department of Geospatial Information Systems K.N. Toosi University of Technology Tehran 19697 Iran Civil Engineering Department K.N. Toosi Universiry of Technology Tehran 19697 Iran

： The first step in any seismic hazard study is the definition of seismogenic sources and the estimation of magnitude-frequency relationships for each source. There is as yet no standard methodology for source modeling and many researchers have worked on this topic. This study is an effort to define linear and area seismic sources for Northern Iran. The linear or fault sources are developed based on tectonic features and characteristic earthquakes while the area sources are developed based on spatial distribution of small to moderate earthquakes. Time-dependent recurrence relationships are developed for fault sources using renewal approach while time-independent frequency-magnitude relationships are proposed for area sources based on Poisson process. GIS functionalities are used in this study to introduce and incorporate spatial- temporal and geostatistical indices in delineating area seismic sources. The proposed methodology is used to model seismic sources for an area of about 500 by 400 square kilometers around Tehran. Previous researches and reports are studied to compile an earthquake/fault catalog that is as complete as possible. All events are transformed to uniform magnitude scale; duplicate events and dependent shocks are removed. Completeness and time distribution of the compiled catalog is taken into account. The proposed area and linear seismic sources in conjunction with defined recurrence relationships can be used to develop time-dependent probabilistic seismic hazard analysis of Northern Iran.

关键词： seismic source modeling geostatistical index seismic hazard GIS

Experimental study of a heavy fuel oil atomization by pressure-swirl injector in the application of entrained flow gasifier

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Chinese Journal of Chemical Engineering 2019年第4期27卷 765-771页

作者： Pouria Mikaniki Seyed mohammad ali Najafi Hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology

The available SMD(Sauter mean diameter) correlations on pressure-swirl injectors predict droplet sizing very different from each other, especially for heavy fuels. Also there was a lack in the literature for comparing available correlations. So an experimental study was conducted on a heavy fuel oil(HFO) spray, Mazut 380. A pressure swirl injector was designed and fabricated. The experiments for Mazut at 40℃ and 80℃ were compared with the results for water, including spray half cone angle, breakup length and mean droplet diameter,at different injection pressures. Lower spray angle, higher breakup length and larger droplets were observed for lower injection pressures and higher liquid viscosity. SMD was about 75 μm for water and about 87 μm for Mazut at 80℃. The results for droplet mean diameter were also compared with correlations from previous studies on pressure swirl atomizers. The SMD results show that for water spray, LISA method was in good agreement,also Babu and Ballester correlations were successful when high viscosity fluid was injected.

关键词： Atomization Pressure-swirl injector Mazut Size distribution Fuel Viscosity

Aircraft robust multidisciplinary design optimization methodology based on fuzzy preference function

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Chinese Journal of Aeronautics 2018年第12期31卷 2248-2259页

作者： ali Reza BABAEI mohammad Reza SETAYANDEH Hamid FARROKHFAL Department of Mechanical and Aerospace Engineering Malek-Ashtar University of Technology

This paper presents a Fuzzy Preference Function-based Robust Multidisciplinary Design Optimization(FPF-RMDO) methodology. This method is an effective approach to multidisciplinary systems, which can be used to designer experiences during the design optimization process by fuzzy preference functions. In this study, two optimizations are done for Predator MQ-1 Unmanned Aerial Vehicle(UAV):(A) deterministic optimization and(B) robust optimization. In both problems, minimization of takeoff weight and drag is considered as objective functions, which have been optimized using Non-dominated Sorting Genetic Algorithm(NSGA). In the robust design optimization, cruise altitude and velocity are considered as uncertainties that are modeled by the Monte Carlo Simulation(MCS) method. Aerodynamics, stability and control, mass properties, performance, and center of gravity are used for multidisciplinary analysis. Robust design optimization results show 46% and 42% robustness improvement for takeoff weight and cruise drag relative to optimal design respectively.

关键词： Fuzzy logic Multidisciplinary design optimization Preference function Robust design Unmanned Aerial Vehicle(UAV)