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Journal of Central South University 2019年第5期26卷 1294-1305页

作者： Peyman MAGHSOUDI gholamreza shahriari Hamed RASAM Sadegh SADEGHI School of Engineering University of TehranTehran ***Iran School of Engineering Iran University of Science and TechnologyTehran ***Iran

The main goal of this paper is to investigate natural convective heat transfer and flow characteristics of non-Newtonian nanofluid streaming between two infinite vertical flat plates in the presence of magnetic field and thermal ***,a similarity transformation is used to convert momentum and energy conservation equations in partial differential forms into non-linear ordinary differential equations (ODE) applying meaningful boundary *** order to obtain the non-linear ODEs analytically,Galerkin method (GM) is ***,the ODEs are also solved by a reliable numerical *** order to test the accuracy,precision and reliability of the analytical method,results of the analytical analysis are compared with the numerical *** respect to the comparisons,fairly good compatibilities with insignificant errors are ***,the impacts of effective parameters including magnetic and radiation parameters and nanofluid volume fraction on the velocity,skin friction coefficient and Nusselt number distributions are comprehensively *** on the results,it is revealed that with increasing the role of magnetic force,velocity profile,skin friction coefficient and thermal performance *** parameter has insignificant influence on velocity profile while it obviously has augmentative and decreasing effects on skin friction and Nusselt number,respectively.

关键词： non-Newtonian flow nanofluid flow Galerkin method magnetic field radiation

Synthesis of boron nitride nanorod and its performance as a metalfree catalyst for oxidative desulfurization of diesel fuel

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Chinese Journal of Chemical Engineering 2024年第4期68卷 120-132页

作者： Tanaz Ghanadi gholamreza Moradi Alimorad Rashidi Catalyst Research Center Faculty of Chemical and Petroleum EngineeringRazi UniversityKermanshahIran Nanotechnology Research Center Research Institute of Petroleum Industry(RIPI)TehranIran

In order to reduce the sulfur compounds in diesel fuel,boron nitride(BN)has been used as a novel metal-free catalyst in the present *** nanocatalyst was synthesized via template-free approach followed by heating treatment at 900℃ in nitrogen atmosphere that the characteristics of the sample were identified by the X-ray diffraction,Fourier-transform infrared spectroscopy,Raman spectroscopy,field emission scanning electron microscopy,transmission electron microscopy,atomic force microscopy,and N2 adsorption-desorption *** results of structural and morphological analysis represented that BN has been successfully *** efficacy of the main operating parameters on the process was studied by using response surface methodology based on the Box-Behnken design *** prepared catalyst showed high efficiency in oxidative desulfurization of diesel fuel with initial sulfur content of 8040 mg·kg^(-1)*** statistical analysis,a significant quadratic model was obtained to predict the sulfur removal as a function of efficient *** maximum efficiency of 72.4%was achieved under optimized conditions at oxidant/sulfur molar ratio of 10.2,temperature of 71℃,reaction time of 113 min,and catalyst dosage of 0.36 ***,the reusability of the BN was studied,and the result showed little reduction in activity of the catalyst after 10 times ***,a plausible mechanism was proposed for oxidation of sulfur compounds on the surface of the *** present study shows that BN materials can be selected as promising metal-free catalysts for desulfurization process.

关键词： Desulfurization Boron nitride(BN)nanostructure Experimental design BoxeBehnken

Suspended particulate matter promotes epithelial-to-mesenchymal transition in alveolar epithelial cells via TGF-β1-mediated ROS/IL-8/SMAD3 axis

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Journal of Environmental Sciences 2024年第7期141卷 139-150页

作者： Shahrzad Molavinia Dian Dayer Mohammad Javad Khodayar gholamreza Goudarzi Maryam Salehcheh Cellular and Molecular Research Center Medical Basic Sciences Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran Department of Toxicology School of PharmacyAhvaz Jundishapur University of Medical SciencesAhvazIran Student Research Committee Ahvaz Jundishapur University of Medical SciencesAhvazIran Toxicology Research Center Medical Basic Sciences Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran Air Pollution and Respiratory Diseases Research Center Ahvaz Jundishapur University of Medical SciencesAhvazIran Iranian Scientific Association of Clean Air TehranIran

Epidemiological evidence presents that dust storms are related to respiratory diseases,such as pulmonary fibrosis(PF).However,the precise underlying mechanisms of SPM-elicited adverse effects still need to be ***-mesenchymal transition(EMT)process is a characteristic of *** discussed whether suspended particulate matter(SPM)is involved in EMT induction via transforming growth factor-β1(TGF-β1).In this study,a detailed elemental analysis(55 elements),particle size,and morphology were *** investigate the toxicity of SPM,an MTT test was performed to detect cell ***,A549cells were exposed to selected concentrations of SPM(20 and 40μg/mL)for single and repeated *** DCFH-DA assay showed that exposure to SPM could produce reactive oxygen species(ROS).The ELISA assay demonstrated increased levels of interleukin-8(IL-8)and TGF-β1 in the *** blot was used to detect the expression of proteins associated with EMT and the SMAD3-dependent *** of western blot demonstrated that E-cadherin was reduced,whereas p-SMAD3,vimentin,andα-smooth muscle actin were *** findings indicated that SPM triggered EMT by induction of oxidative stress,inflammation,and the TGF-β1/SMAD3 pathway activation.

关键词： Particulate matter TGF-β1 Oxidative stress Epithelial-mesenchymal transition Pulmonary fibrosis Cells

Using satellite-derived land surface temperatures to clarify the spatiotemporal warming trends of the Alborz Mountains in northern Iran

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Journal of Mountain Science 2024年第2期21卷 449-469页

作者： ROSHAN gholamreza SARLI Reza GHANGHERMEH Abdolazim TAHERIZADEH Mehrnoosh NIKNAM Arman Department of Geography Golestan UniversityGorgan 49138-15759Iran Department of Forest Resources Management Faculty of ForestryUniversity of Agriculture in KrakowAL.29 Listopada 4631-425 KrakówPoland Department of Geoinformatics Physical and Environmental GeographyUniversity of SzegedSzeged 6722Hungary

The Alborz Mountains are some of the highest in Iran,and they play an important role in controlling the climate of the country’s northern *** land surface temperature(LST)is an important variable that affects the ecosystem of this *** study investigated the spatiotemporal changes and trends of the nighttime LST in the western region of the Central Alborz Mountains at elevations of 1500-4000 m above sea *** data were extracted for the period of 2000-2021,and the Mann-Kendall nonparametric test was applied to evaluating the changes in the *** results indicated a significant increasing trend for the monthly average LST in May-August along the southern *** the northern and southern aspects showed decreasing trends for the monthly average LST in October,November,and March and an increasing trend in other *** all elevations,the average decadal change in the monthly average LST was more severe along the southern aspect(0.60°C)than along the northern aspect(0.37°C).The LST difference between the northern and southern aspects decreased in the cold months but increased in the hot *** the same elevation,the difference in the lapse rate between the northern and southern aspects was greater in the hot months than in the cold *** increasing elevation,the lapse rate between the northern and southern aspects *** change was concluded to greatly decrease the difference in LST at different elevations for April-July.

关键词： Global warming Mountainous areas Lapse rate Surface air temperatures Alborz

Plantago Ovata Efficiency in Elimination of Water Turbidity

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Journal of Water Resource and Protection 2009年第2期1卷 90-98页

作者： gholamreza Nabi BIDHENDI Toktam shahriari Sh shahriari 不详

Coagulation and flocculation are the most important processes in water treatment plants. Nowadays, in Iran, coagulants which have the most usage in water treatment are Aluminum Sulphate (Alum) and Ferric Chlo-ride. Using synthetic coagulants are not economical and useful for health in developing countries. The aim of this research is to survey and compare the Ferric Chloride coagulant function and this coagulant accompany with Plantago ovata coagulant aid under variable pH for eliminating of water turbidity. This study was performed in lab scale for water containing artificial turbidity of clay. The experiments were done in three turbidity ranges 100, 50, 20 NTU and two ranges of pH 7 and 8. The amount of Ferric Chloride in all experiments were 10 ppm and *** extarct in optimum concentration for turbidity of 100, 50, 20 NTU was 0.2 ppm, 0.1 ppm and 0.04 ppm respectively. The optimum pH was 7. Using *** co-agulant aid in turbidity 100, 50, 20 NTU can eliminate 94.1, 94.5, 88.15 percent of above turbidities, while using Ferric Chloride coagulant alone in optimum pH can eliminate 90.3, 85.16, 80.2 percent of the turbid-ities mentioned above. Results show that *** extract is less efficient in high turbidities when used as a coagulant aid. Plantago ovata, as a coagulant aid, showed positive influence on turbidity removal from water. In addition, optimized pH showed important role in reducing turbidity.

关键词： Water Treatment Coagulation and Flocculation Jar Test Turbidity Plantago Ovata Ferric Chloride

OPERATOR NORM AND LOWER BOUND OF FOUR-DIMENSIONAL GENERALIZED HAUSDORFF MATRICES

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Acta Mathematica Scientia 2022年第1期42卷 429-436页

作者： gholamreza TALEBI Department of Mathematical sciences Vali-e-Asr University of RafsanjanRafsanjanIslamic Republic of Iran

The problem addressed is the exact determination of the operator norm and lower bound of four-dimensional generalized Hausdorff matrices on the double sequence spaces L_(p).A Hardy type formulae is found as an exact value for their operator norm and a Copson type formulae is established as a lower estimate for their lower ***,exact values are found for the operator norm and lower bound of the transpose of generalized Hausdorff matrices.

关键词： four-dimensional Hausdorff matrices

Effect of transparency on Josephson junction between s+g-wave superconductors

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Chinese Physics B 2010年第10期19卷 499-504页

作者： gholamreza Rashedi Department of Physics University of Isfahan

In this paper, a dc Josephson junction between borocarbide superconductors has been studied theoretically. The s＋g-wave pairing symmetry which is observed in rare earth complex of borocarbides has a huge anisotropy and is an interesting form of unconventional superconductivity. We calculate the Josephson current in a superconductorinsulator-superconductor （SIS） Josephson junction with s＋g-wave superconducting pairing symmetry. In our planar junction c-axis is parallel to an interface with finite transparency but ab-planes of two tetragonal superconductors are misorientated by angle α. We obtain that the Josephson current is strongly dependent on mis-orientation between the left and the right ab-planes. An insulator sandwiched between two superconductors which acts as a potential barrier is demonstrated by a transparency coefficient. The effects of the potential barrier and the mis-orientation on the current are studied analytically and numerically. Occurrence of 0-θ transition in this s＋g-wave junction is investigated in this paper. A comparison between d-wave Josephson junction and s＋g-wave one is also made in the present paper.

关键词： Josephson junction unconventional superconductor borocarbides

Investigation of a novel pyrogenic pulser in a laboratory motor

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Chinese Journal of Aeronautics 2020年第1期33卷 134-148页

作者： Roohollah TAHERINEZHAD gholamreza ZAREPOUR Department of Mechanical Engineering University of GuilanRasht 51665-315Iran

In this paper,a novel pyrogenic pulser was designed both analytically and numerically and was evaluated with empirical *** motivation of this study was the need for active control of the aero acoustic pressure oscillations by injecting the secondary flow into the solid rocket ***,in brief,pyrotechnic and pyrogenic pulsers were introduced,and then analytical governing equations were presented in three transient,sinusoidal and Hercules *** order to understand the internal pressure of the pulsar and its plume length,the injection flow field was evaluated using the ANSYS-Fluent software with both k-ωSST and k-εRealizable models both at ambient and motor *** that,the design and manufacturing of the pulser hardware and the test process were ***,analytical,numerical and experimental results were *** results show that there is a good correlation between the transient analysis in theory and the numerical solution by the k-ωSST model and the empirical test *** addition,pyrogenic pulsers design depends on various parameters of motor and pulser charge performance *** quality of pulser charge bonding to its insulator and erosion of its throat path due to injection have an important role to obtain a desirable pulser mass flow rate and plume length.

关键词： Aero acoustic Pressure oscillation Pyrogenic pulsers Secondary injection Solid rocket motors

Evaluation of pressure oscillations by a laboratory motor

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Chinese Journal of Aeronautics 2020年第3期33卷 805-825页

作者： Roohollah TAHERINEZHAD gholamreza ZAREPOUR Department of Mechanical Engineering University of GuilanRasht 51665-315Iran

Aeroacoustic pressure oscillation is one of the important challenges in segmented solid rocket motors with high slenderness *** reason for these oscillations can be searched in vortex shedding due to grain burning surfaces, holes and *** this paper, a novel sub-scaled motor was used for evaluation of aeroacoustic pressure ***, the related parameters to scale down using Buckingham's Pi-theorem were determined and then the sub-scaled motor was designed and *** this, Strouhal number in various grain forms and vortex shedding prediction criteria have been ***, one-dimensional linear and non-linear solution approaches have been *** understand the motor internal flow and vortex shedding formation, steady state computational fluid dynamic performed for seven regression steps and finally, two static tests have been *** show that various definitions for Strouhal number are useful only for primarily glance on vortex shedding and pressure oscillations and so CFD solution and the test program are inevitable for a correct understanding of the ballistic operational condition of the *** results demonstrated the existence of such oscillations with frequencies nearly equal to axial *** seems that non-linear parameters have small effects on aeroacoustic pressure oscillation and therefore the linear solution is acceptable to obtain approximate *** course,it should be emphasized that linear solution represents oscillations on overall motor action time,whereas the output of non-linear solution depends on thermochemistry properties of solid propellant and combustion ***, with a non-linear solution, oscillations maybe occur in some intervals of action ***(Fast Fourier Transformation) results demonstrated that although both first and second acoustic modes have been excited, the position of longitudinal oscillation has an important role on which one is dominant.

关键词： Aeroacoustic Pressure oscillation Solid rocket motor Strouhal number Sub-scale Vortex shedding

Proposal of a probabilistic assessment of structural collapse concomitantly subject to earthquake and gas explosion

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 425-437页

作者： gholamreza ABDOLLAHZADEH Hadi FAGHIHMALEKI Department of Civil Engineering Babol Noshirvani University of Technology Shariati Av. Babol Mazandaran Iran

In recent decades, many public buildings, located in seismic-prone residential areas, had to grapple with abnormal loads against which the structures were unguarded. In this piece of research, an ordinary three dimensional reinforced concrete building is selected as case study. The building is located in an earthquake-prone region; however, it is designed according to seismic building codes. Yet, it is not shielded against abnormal loads, such as blasts. It is assumed that the building suffers a blast load, due to mechanical/thermal installation failure during or after intense seismic oscillations. These two critical incidents are regarded codependent and compatible. So the researchers developed scenarios and tried to assess different probabilities for each scenario and carried out an analysis to ensure if progressive collapse had set in or not. In the first step, two analysis models were used for each scenario; a non-linear dynamic time history analysis and a blast local dynamic analysis. In the second step, having the structural destructions of the first step in view, a pushdown analysis was carried out to determine the severity of progressive collapse and assess building robustness. Finally, the annual probability of structural collapse under simultaneous earthquake and blast loads was estimated and offered.

关键词： gas blast pushdown analysis progressive collapse annual probability of structural collapse 3D model of structure