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Effects of nitric oxide on reproductive organs and related physiological processes

Asian pacific Journal of Reproduction 2020年第4期9卷 159-165页

作者： Ayoob Rostamzadeh Reza Ahmadi mahdi heydari Amir Raoofi Student Research Committee Department of Anatomical SciencesFaculty of MedicineIran University of Medical SciencesTehranIran Clinical Biochemistry Research Center Basic Health Sciences InstituteShahrekord University of Medical SciencesShahrekordIran Leishmaniasis Research Center Department of AnatomySabzevar University of Medical SciencesSabzevarIran

Nitric oxide(NO),a member of the reactive nitrogen species family,plays a role in several physiologic processes,including vasculogenesis and angiogenesis,growth and puberty,and senescence and *** plays an important role in the production of ovarian steroids,ovulation,and follicular *** other words,increased activity of nitric oxide synthase(NOS)leads to an increased amount of NO,which triggers production of prostaglandins and inflammatory cascades which facilitate follicular rupture and *** concentration elevation inhibits steroid synthesis in luteal and granulosa *** NO is a major paracrine mediator of various biological processes,as well as a key factor in both the reproductive cycle and embryo implantation,oversynthesis of NO in the uterus results in toxicity and inflammation in epithelial cells and immunorejection of *** the male physiological system,NO synthesized by NOS plays a major role in erectile function and androgen secretion,as well as semen parameters,and oocyte junction to the ***,this supposedly simple molecule is involved in a number of other functions,such as germ cell evolution,connections between sertoli cells and germ cells in the blood-testis barrier,homodynamic contraction,and germ cell ***,NO is considered a key factor in male fertility due to its widespread distribution in both normal and diseased testis *** difference of expression level of NOS in normal and pathological states is a probable cause of fertility destructive processes.

关键词： Reproduction Nitric oxide Nitric oxide synthase Cell signaling Oxidants

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Kink-band Kinematic Analysis and its Implications for Late-stage Deformation in the Internal Parts of the Zagros Collision(Sanandaj–Sirjan Zone) in West Iran

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 921-935页

作者： Maryam heydari mahdi BEHYARI Department of Geology Faculty of SciencesUrmia University57153165 UrmiaIran

In the internal parts of the Zagros collision zone, several deformation phases have been superimposed. The early deformation phase caused the development of a penetrative foliation. The late-stage deformation phase was preferentially accommodated within shear zones and caused the generation of shear bands, implying a non-coaxial component of deformation, the end of this stage deformation was marked by the development of kink-bands. In the vicinity of Zagros suture zone, the kink angle increased from 40° to 60°, and the kink-bands was converted to chevron folds. In this region, the external(α) and internal(β) angular ratio is α/β ≠ 1 and kink angle increased, and deformation occurred with 10% to 30% volume loss. Farther from the suture zone in the east, α/β = 1;and total volume was constant or increased by 5% to 10%. Kink-bands kinematic analysis in the study area revealed this structures were sensitive to deformation conditions and components such that, with decreasing distance to the Zagros suture zone, shearing and rotation increased, a high kinematic vorticity dominated, and volume loss occurred during deformation.

关键词： kink-band shear zone strain vorticity Zagros Iran

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Novel application of PEG/SDS interaction as a wettability modifier of hydrophobic carbonate surfaces

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Petroleum Science 2019年第2期16卷 318-327页

作者： Nasim heydari mahdi Asgari Narjes Shojai Kaveh Zahra Fakhroueian School of Chemical Engineering Iran University of Science and Technology School of Chemical Engineering College of EngineeringUniversity of Tehran Department of Geoscience and Engineering Delft University of Technology

Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of surfactants in EOR applications. In this study, the interaction of polyethylene glycol(PEG) with an ionic surfactant, sodium dodecyl sulphate(SDS),is evaluated on an oil-wet carbonate rock surface by using contact angle measurements. The results reveal that wettability alteration of carbonate rocks is achieved through PEG/SDS interaction on the rock surface above a critical aggregation concentration(CAC). The behaviour of PEG/SDS aqueous solutions is evaluated using surface and interfacial tension measurements. Furthermore, the effect of PEG and SDS concentrations and impact of electrolyte addition on PEG/SDS interaction are investigated. It is shown that electrolyte(NaCl) can effectively decrease the CAC values and accordingly initiate the wettability alteration of rocks. Moreover, in a constant SDS concentration, the addition of NaCl leads to a reduction in the contact angle, which can also be obtained by increasing the aging time, temperature and pre-adsorption of PEG on the rock surface.

关键词： Sodium dodecyl sulphate (SDS)- Polyethylene glycol (PEG)- Wettability alteration Contact angle Critical aggregation concentration Carbonate surface

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Highly regioselective synthesis of dicyano-8a,10,11-trihydropyrrolo[1,2-α][1,10]phenanthrolines via a domino-Knoevenagel-cyclization

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Chinese Chemical Letters 2011年第11期22卷 1281-1284页

作者： Reza heydari Batool Tahamipour Department of Chemistry The University of Sistan and Baluchestan P.O.Box 98135-674ZahedanIran

1,10-Phenanthrolinium N-ylides,can react with malonitrile and aromatic aldehydes via a domino-Knoevenagel cyclization to afford a new class of trihydropyrrolo[1,2-a][l,10]phenanthroline derivatives as stable helical c... 详细信息

关键词： 1 10-Phenanthrolinium N-ylide Domino-Knoevenagel-cyclization Trihydropyrrolo[1 2-a][1 10]phenanthrolines Multicomponent reaction

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An experimental investigation on the effect of grain size on oil-well sand production

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Petroleum Science 2012年第3期9卷 343-353页

作者： Vahidoddin Fattahpour mahdi Moosavi mahdi Mehranpour School of Mining Engineering the University of Tehran

Sand production in oil wells is closely related to the mechanical behavior and petrographical properties of sandstones reservoir. Grain size is one of the main parameters controlling the phenomenon, which is studied in this paper. Large-scale hollow cylindrical synthetic samples with the same rock strength but different grain sizes were tested by an experimental setup in the laboratory. Different external stresses and fluid flow rates were applied to the samples and produced sand was measured continuously. Results show two different trends between sanding stress level and grain size. For the samples with finer grain size （D50〈0.3 mm）, the required confining stress for different sanding levels decreased with an increase in the grain size and for the samples with the coarser grains （D50〉0.3 mm） the required confining stress for different sanding levels dramatically increased with an increase in the grain size. Those two different trends were discussed and explained. The first one was production of individual grains and the second was bigger chunks in the slab form. In samples with large grains, plastic zones around hole were changed to a completely loose zone including interlocked individual grains or cluster of grains. In these samples after breakage of these interlocked zones sand was produced in the form of individual grains and clusters. Contrary to this, for samples with smaller grain size, shear bands were formed around the plastified hole and sand was produced in the form of big chunks or slabs.

关键词： Sand production experimental tests grain size perforation size

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Haar wavelet method for solving nonlinear age-structured population models

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International Journal of Biomathematics 2017年第8期10卷 163-183页

作者： Zakieh Avazzadeh Mohammad heydari Institute of Mathematics School of Mathematical SciencesNanjing Normal University Nanjing 210023 P. R. China Department of Mathematics Yazd University P. O. Box 89195-741 Yazd Iran

In this study, Haar wavelet method is implemented for solving the nonlinear age- structured population model which is the nonclassic type of partial differential equation associated with boundary integral equation. This paper develops the flexibility of Haar wavelet method for reduction of the partial differential equation with nonlocal boundary conditions to an algebraic system. In fact, the simple structure of piecewise orthogonM Haar basis functions which leads to sparse matrices causes the convergence and com- putational efficiency. Some illustrative results show the reliability and accuracy of the presented method.

关键词： Nonlinear age-structured population model Haax wavelet boundary integralequation.

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Initial estimation of hydrate formation temperature of sweet natural gases based on new empirical correlation

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Journal of Natural Gas Chemistry 2012年第5期21卷 508-512页

作者： Mohammad mahdi Ghiasi Petroleum University of Technology Ahwaz Faculty of PetroleumPost Box:63431AhwazIran

Production,processing and transportation of natural gases can be significantly affected by clathrate *** the gas analysis is crucial to predict the right conditions for hydrate ***,Katz gas gravity method can be used for initial estimation of hydrate formation temperature （HFT） under the circumstances of indeterminate gas *** far several correlations have been proposed for gas gravity method,in which the most accurate and reliable one has belonged to Bahadori and *** main objective of this study is to present a simple and yet accurate correlation for fast prediction of sweet natural gases HFT based on the fit to Katz gravity *** reviewing the error analysis results,one can discover that the new proposed correlation has the best estimation capability among the widely accepted existing correlations within the investigated range.

关键词： natural gas hydrates hydrate formation temperature gas gravity method empirical correlation

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Effective Controlled Islanding Method for Power Grids Solving a Sequence of Optimization Problems

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1004-1012页

作者： mahdi Amini Haidar Samet Ali Reza Seifi mahdi Davarpanah School of Electrical and Computer Engineering Shiraz UniversityShirazIran Department of Electrical Engineering Eindhoven University of TechnologyEindhoventhe Netherlands the Electrical and Computer Engineering School College of EngineeringUniversity of TehranTehranIran

Controlled islanding is an important approach to prevent instability in power *** this paper,a novel approach is proposed for power system separation,which consists of two steps:1)Finding multiple islanding scenarios;2)Choosing the best option to obtain the most desirable *** the first step,different islanding solutions are determined by a proposed hierarchical clustering *** this algorithm,which is based on a minimum active power flow disruption objective function,the generator coherency constraints are considered in the clustering *** the second step,the best separation scenario is chosen based on an arbitrary objective ***,in this paper,the amount of load shedding and the voltage profile deviation after separation are considered as the final criteria to select the best solution among available *** so doing,the degree of load importance is also taken into *** proposed two-step method is applied on an IEEE 9-bus test system and it is also evaluated on an IEEE 39-bus *** simulation results on the IEEE 39-bus grid and the comparative analysis with a state-of-the-art method confirm that the final islanding solution is more optimized based on the secondary criteria,which have not been addressed in the existing ***,the proposed method is computationally efficient and can be employed in real-scale power grids.

关键词： Graph theory hierarchical spectral clustering power system separation power system instability two-step approach.

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Vanadium oxide nanotubes for selective catalytic reduction of NO_x with NH_3

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Chinese Journal of Chemical Engineering 2016年第7期24卷 914-919页

作者： Seyed mahdi Mousavi Faculty of Chemistry University of Kashan

Vanadium oxide （VOx） nanostructures, synthesized by hydrothermal treatment using dodecylamine as template, were evaluated for the selective catalytic reduction of NOx with ammonia （NH3-SCR）, The effect of solvent type in the reaction mixture （EtOH/（EtOH ＋ H20）） and time of hydrolysis was studied. The obtained materials were characterized by XRD, SEM, TEM and BET, The VOx nanorods （80-120 nm diameter and 1-4 μm length） were synthesized in 25 vol% EtOH/（EtOH ＋ H20） and the open-ended multiwalled VOx nanotube （50-100 nm inner diameter, 110-180 nm outer diameter and 0,5-2 pm length） synthesized in 50 vol% EtOH/（EtOH ＋ H20）. VOx nanotuhes performed the superior NH3-SCR activity under a gas hourly space velocity of 12,000 h-1 at low temperature of 250 ~C （NOx conversion of 893g ＆ N2 selectivity of 100%）, while most of the developed Vanadia base catalysts are active at high temperature （〉350 ℃）. The superior NH3-SCR activity ofVOx nanotubes at low tem- perature is related to nanocrystalline structure, special nanotube morphology as well as high specific surface area.

关键词： Hydrothermal Nanotubes NOx Pollution SCR

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Numerical study of flow and thermal characteristics of pulsed impinging jet on a dimpled surface

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 106-117页

作者： Amin Bagheri Kazem Esmailpour Morteza heydari Renewable Energy Research Center Damavand BranchIslamic Azad UniversityDamavandIran

This research comprehensively investigates the flow and thermal characteristics of a pulsating impinging jet over a dimpled *** analyzes the impact of key parameters(e.g.,inlet velocity pulsation functions,pulsation frequency,amplitude,dimple pitch,dimple depth,Reynolds number)on flow patterns and heat *** computational fluid dynamics and the Re-normalization group turbulence model are employed to accurately simulate complex turbulent flow *** and average heat transfer coefficients are calculated and compared to steady impingement cases,revealing the potential benefits of pulsation for heat transfer *** study also examines how pulsation-induced flow modulation and thermal mixing affect heat transfer *** indicate that combining fluctuating flow with a dimpled surface can improve heat transfer *** summary,increasing pulsation amplitude consistently enhances heat transfer,while the effect of frequency varies between impinging and wall jet zones.

关键词： Pulsating impinging jet Dimpled surface Heat transfer enhancement Pulsation frequency and amplitude Coherent structures

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