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Stratigraphical Study of the Taft Formation in the Bohruk Area from Yazd Block, Central Iran

Journal of Earth Science 2015年第5期26卷 729-739页

作者： seyed Ahmad Babazadeh Taiebeh Esmaeili Dehej Department of Science Payame Noor University

The Taft Formation is exposed at the Bohruk area from Yazd Block in central Iran with 136 m thickness comprising three informal members which are named, in ascending stratigraphical order named Lower, Middle and Upper members. The Lower and Upper members consist of bioclastic carbonate rocks, whereas the Middle Member contains two sub-members： carbonate and siliciclastic carbonate rocks. Four patterns of facies are recognized on the basis of field observation and microscopic study. They are grainstone facies, siliciclastic-carbonate facies, intermediate facies（grainstone-wackestone/packstone facies） and foraminiferal-clastic wackestone/packstone facies. Based on the facies associations, three facies belts are presented for the first time. Therefore, this formation was deposited on a shallow carbonate platform from the inner platform to rimmed platform. The main fauna of the Taft Formation include Istriloculina eliptica（Iovcheva）, Palorbitolina lenticularis（Blumenbach）, Charentia cuvillieri Neumann, Everticyclammina hedbergi（Maync）, Pseudocyclammina litus（Yokoyama）, Melathrokerion valserinensis Bronnimann ＆ Conrad, Nautiloculina oolithica Mohler, Glomospira urgoniana Arnaud Vanneau, Dicyclina schlumbergeri MunierChalmas, Derventina filipescui Neagu, Praechrysalidina infracretacea Luperto-Sinni, Pseudochoffatella cuvillieri Deloffre, Paracoskinolina sp., Textularia sp., and Lenticulina sp. Based on the foraminiferal distribution throughout the Taft Formation, two biozones like Istriloculina ellipticaPalorbitolina lenticularis zone and Glomospira urgoniana-Dicyclina schlumbergeri zone are recognized they and range from the Late Barremian to Early Albian in age.

关键词： Stratigraphy Taft Formation Central Iran Yazd Block Lower Cretaceous

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On the Nonorientable Genus of the Generalized Unit and Unitary Cayley Graphs of a Commutative Ring

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Algebra Colloquium 2022年第1期29卷 167-180页

作者： Mahdi Reza Khorsandi seyed Reza Musawi Faculty of Mathematical Sciences Shahrood University of Technology P.O.Box 36199-95161ShahroodIran

Let R be a commutative ring and U(R)the multiplicative group of unit elements of *** 2012,Khashyarmanesh et *** the generalized unit and unitary Cayley graph,T(R,G,S),corresponding to a multiplicative subgroup G of U(R)and a nonempty subset S of G with S^(-1)={s^(-1)|s∈S}■S,asthegraphwithvertexsetR and two distinct vertices x and y being adjacent if and only if there exists s∈S such that x+sy∈*** this paper,we characterize all Artinian rings R for which T(R,U(R),S)is *** leads us to determine all Artinian rings whose unit graphs,unitary Cayley graphs and co-maximal graphs are *** addition,we prove that for an Artinian ring R for which T(R,U(R),S)has finite nonorientable genus,R must be a finite ***,it is proved that for a given positive integer k,the number of finite rings R for which T(R,U(R),S)has nonorientable genus k is finite.

关键词： unit graph unitary Cayley graph co-maximal graph projective graph nonorientable genus

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Flow-mode synthesis of biodiesel under simultaneous microwave–magnetic irradiation

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2551-2559页

作者： Behzad Khedri Mostafa Mostafaei seyed Mohammad Safieddin Ardebili Mechanics of Biosystems Engineering Department Razi UniversityKermanshahIran Biosystems Engineering Department Shahid Chamran University of AhvazAhvazIran

In this study,aiming at optimization of a novel continuous biodiesel production system was developed by combining technologies based on microwaves and magnetic *** affecting microwave-assisted biodiesel(alkyl esters)production reaction were analyzed in this *** factors included magnetic field intensity(0,0.225 and 0.450 T),microwave power(400,821,and 1181 W),percentages of KOH and Na OH catalysts at constant concentrations of 1 wt%(0,50%and 100%),and percentages of ethanol and methanol at a constant molar ratio of 6:1(0,50%and 100%).Response Surface Methodology(RSM)was used to optimize the reaction ***-based analysis indicated that,all independent parameters had significant effects on the reaction *** of the investigations reveal that the largest effects on the conversion efficiency were due to type of alcohol and magnetic field *** optimized conditions were found to be a magnetic field intensity of 0.331 T,a microwave power of 677.77 W,catalyst percentages of 30.35%and 69.65%for KOH and Na OH,respectively,and alcohol percentages of 80.47%and 19.53%for methanol and ethanol,*** the optimal conditions,yield of the reaction was 96.2%.

关键词： Biodiesel Microwave Magnetic field Transesterification Waste cooking oil

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Temperature and Input Energy Dependence of the 946-nm Stimulated Emission Cross Section of Nd^(3+):YAG Pumped by a Flashlamp

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Chinese Physics Letters 2012年第3期29卷 104-106页

作者： seyed Ebrahim Pourmand Noriah Bidin Hazri Bakhtiar Laser Research Group Nanotechnology Research AllianceAdvance Photonic Science InstituteFaculty of ScienceUniversity TeknologiMalaysia

The thermal effect on the laser transition at 946nm is *** temperature of the cooling system is verified in the range 2-60℃.A Nd:YAG laser crystal is utilized as a gain medium and is pumped by a newly developed *** variable pumping energy is accomplished within the 5-40 d *** stimulated emission cross section of the 946-nm line is estimated based on the fluorescence spectrum of the Nd:YAG *** stimulated emission cross section of the 946-nm line is found to be inversely proportional to the temperature and to the input energy due to the increase of the thermal population at the ground level.

关键词： Nd:YAG pumped pumping

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Vegetation composition differentiation and species-environment relationships in the northern part of Isfahan Province, Iran

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Journal of Arid Land 2017年第2期9卷 161-175页

作者： Hadi KARGAR-CHIGANI seyed Akbar JAVADI Ghavamodin ZAHEDI-AMIRI seyed Jamaleddin KHAJEDDIN Mohamad JAFARI Department of Range Management Science and Research Branch Islamic Azad University Faculty of Natural Resources University of Tehran Range and Watershed Management Division Department of Natural Resources Isfahan University of Technology

A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province （Iran） using two-way indicator species analysis （TWINSPAN）, detrended correspondence analysis （DCA）, principal component analysis （PCA）, and canonical correspondence analysis （CCA）. Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors （selected by PCA） used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, CaCO3 content, and grazing intensity and that the second axi

关键词： rangeland classification ordination multivariate analysis plant groups Isfahan Province

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Reservoir volume optimization and performance evaluation of rooftop catchment systems in arid regions: A case study of Birjand, Iran

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Water Science and Engineering 2017年第2期10卷 125-133页

作者： Zinat Komeh Hadi Memarian seyed Mohammad Tajbakhsh Faculty of Natural Resources and Environment University of Birjand Birjand 97175 Iran

This study evaluated the performance of rooftop catchment systems in securing non-potable water supply in Birjand, located in an arid area in southeastern Iran. The rooftop catchment systems at seven study sites of different residential buildings were simulated for dry, normal, and wet water years, using 31-year rainfall records. The trial and error approach and mass diagram method were employed to optimize the volume of reservoirs in five different operation scenarios. Results showed that, during the dry water year from 2000 to 2001, for reservoirs with volumes of 200-20000 L, the proportion of days that could be secured for non-portable water supply was on average computed to be 16.4%-32.6% across all study sites. During the normal water year from 2009 to 2010 and the wet water year from 1995 to 1996, for reservoirs with volumes of 200-20000 L, the proportions were 20.8%-69.6% and 26.8%-80.3%, respectively. Therefore, a rooftop catchment system showed a high potential to meet a significant portion of non-potable water demand in the Birjand climatic region. Reservoir volume optimization using the mass diagram method produced results consistent with those obtained with the trial and error approach, except at sites #1, #2, and #5. At these sites, the trial and error approach performed better than the mass diagram method due to relatively high water consumption. It is concluded that the rooftop catchment system is applicable under the same climatic conditions as the study area, and it can be used as a drought mitigation strategy as well.

关键词： Mass diagram analysis Non-potable water demand Reservoir volume optimization Rooftop catchment Rainwater harvesting

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A Feature Model Based Framework for Refactoring Software Product Line Architecture

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Journal of Computer Science & Technology 2016年第5期31卷 951-986页

作者： Mohammad Tanhaei Jafar Habibi seyed-Hassan Mirian-Hosseinabadi Department of Computer Engineering Sharif University of Technology Tehran 11155-9517 Iran

Software product line （SPL） is an approach used to develop a range of software products with a high degree of similarity. In this approach, a feature model is usually used to keep track of similarities and differences. Over time, as modifications are made to the SPL, inconsistencies with the feature model could arise. The first approach to dealing with these inconsistencies is refactoring. Refactoring consists of small steps which, when accumulated, may lead to large-scale changes in the SPL, resulting in features being added to or eliminated from the SPL. In this paper, we propose a framework for refactoring SPLs, which helps keep SPLs consistent with the feature model. After some introductory remarks, we describe a formal model for representing the feature model. We express various refactoring patterns applicable to the feature model and the SPL formally, and then introduce an algorithm for finding them in the SPL. In the end, we use a real-world case study of an SPL to illustrate the applicability of the framework introduced in the paper.

关键词： software product line feature model refactoring software architecture

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Numerical analysis of reactive turbulent flow in the thrust chamber of RD-108 engine rocket

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Defence Technology（防务技术） 2019年第4期15卷 565-575页

作者： seyed Reza Taghavi Mohammad Ali Dehnavi Ali Ghafouri Department of Chemical Engineering Imam Hossein Comprehensive University

Combustion chamber modeling and simulation of the liquid propellant engine with kerosene as fuel and liquid oxygen as an oxidizer in the turbulent flow field are performed by CFD *** flow is modeled as Single-phase in steady state and using RNG k-ε turbulence *** results are validated by experimental data of thrust,special impulse and combustion chamber *** comparing t.^wo reaction models of finite rate chemistry and frozen model with experimental data,it is concluded that finite rate chemistry has acceptable *** optimum value of equivalence ratio(oxidizer to fuel ratio)per reaction and operational parameters of the engine which maximize thrust and special impulse are determined.

关键词： Liquid propellant engine Computational fluid dynamics(CFD) Kerosene and oxygen Freeze model Finite rate chemistry model

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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

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Electrochemical Behavior of Passive Films Formed on the Surface of Coarse-,Fine-and Ultra-fine-Grained AA1050 Based on a Modified PDM

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Acta Metallurgica Sinica(English Letters) 2016年第7期29卷 629-637页

作者： seyed Omid Gashti Arash Fattah-alhosseini Yousef Mazaheri Department of Materials Engineering Bu-Ali Sina University

Electrochemical impedance spectroscopy （EIS） and Mott-Schottky analysis were carried out to evaluate the electrochemical behavior of the passive films formed on the surface of coarse-grained （CG）, fine-grained （FG） and ultrafine-grained （UFG） 1050 A1 alloy （AA1050） samples in alkaline media （pH value of 8.0） based on a modification of point defect model （PDM）. The EIS results revealed that the polarization resistance increased from about 22.71-120.33 kΩ cm2 for UFG sample when compared to CG sample （annealed sample）. The semiconductor properties of the passive films formed on CG, FG and UFG AA1050 samples in the test solution were investigated by employing Mott-Schottky analysis in conjunction with PDM. The results indicated that donor densities were in the range of 2.19 × 1021-0.61 × 1021 cm-3 and decreased with grain refinement. Finally, all electrochemical tests showed that the electrochemical behavior of AA1050 alloy was improved by decreasing the grain size, mainly due to the formation of thicker and less defective oxide films.

关键词： AA1050 alloy Grain refinement Ultra-fine grain (UFG) Passive film Mott-Schottky

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