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Petroleum Science 2012年第4期9卷 485-497页

作者： SADRNEJAD S A ghasemzadeh h GhOREIShIAN AMIRI S A MONTAZERI G h Faculty of Civil Engineering K.N.Toosi University of Technology Research and Development Department Iranian Central Oil Field Co.

Applying the standard Galerkin finite element method for solving flow problems in porous media encounters some difficulties such as numerical oscillation at the shock front and discontinuity of the velocity field on element *** of velocity field leads this method not to conserve mass ***,the accuracy and stability of a solution is highly affected by a non-conservative *** this paper,a three dimensional control volume finite element method is developed for twophase fluid flow simulation which overcomes the deficiency of the standard finite element method,and attains high-orders of accuracy at a reasonable computational ***,this method is capable of handling heterogeneity in a very rational way.A fully implicit scheme is applied to temporal discretization of the governing equations to achieve an unconditionally stable *** accuracy and efficiency of the method are verified by simulating some waterflooding *** representative examples are presented to illustrate the capability of the method to simulate two-phase fluid flow in heterogeneous porous media.

关键词： Finite element method control volume two-phase flow heterogeneity porous media waterflooding

Application of control volume based finite element method for solving the black-oil fluid equations

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Petroleum Science 2013年第3期10卷 361-372页

作者： GhOREIShIAN AMIRI S A SADRNEJAD S A ghasemzadeh h MONTAZERI G h Faculty of Civil Engineering K. N. Toosi University of TechnologyTehran Iran Research and Development Dept. Iranian Central Oil Field Co.Tehran Iran

This is the second paper of a series where we introduce a control volume based finite element method （CVFEM） to simulate multiphase flow in porous media. This is a fully conservative method able to deal with unstructured grids which can be used for representing any complexity of reservoir geometry and its geological objects in an accurate and efficient manner. In order to deal with the inherent heterogeneity of the reservoirs, all operations related to discretization are performed at the element level in a manner similar to classical finite element method （FEM）. Moreover, the proposed method can effectively reduce the so-called grid orientation effects. In the first paper of this series, we presented this method and its application for incompressible and immiscible two-phase flow simulation in homogeneous and heterogeneous porous media. In this paper, we evaluate the capability of the method in the solution of highly nonlinear and coupled partial differential equations by simulating hydrocarbon reservoirs using the black-oil model. Furthermore, the effect of grid orientation is investigated by simulating a benchmark waterflooding problem. The numerical results show that the formulation presented here is efficient and accurate for solving the bubble point and three-phase coning problems.

关键词： Control volume based finite element,black-oil model grid orientation porous media

Effect of External Forced Flow and Boiling Film on heat Transfer of AISI 4140 Steel horizontal Rod During Direct Quenching

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Journal of Iron and Steel Research International 2011年第10期18卷 34-41页

作者： A h Meysami R ghasemzadeh S h Seyedein M R Aboutalebi Department of Metallurgy and Material Engineering Golpayegan University Centre of Excellent for Advanced Material and Processing School of Metallurgy and Material EngineeringIran University of Science and Technology

The effects of rod falling and moving, external flow field, boiling film and radiation were investigated on fluid flow and heat transfer of AISI 4140 steel horizontal rod during direct quenching by mathematical modeling. The flow field and heat transfer in quenching tank were simulated by computational fluid dynamics （CFD） method considering falling and moving of rods during process. Therefore, modeling of flow field was done by a fixed-mesh method for general moving objects equations, and then, energy equation was solved with a numerical approach so that effeet of boiling film heat flux was considered as a source term in energy equation for solid-liquid boundary. Simulated results were verified by comparing with published and experimental data and there was a good agreement between them. Also, the effects of external forced flow and film boiling were investigated on heat flux output, temperature distribution and heat transfer coefficient of rod. Also simulated results determined optimum quenching time for this process.

关键词： direct quenching AISI 4140 moving object heat transfer modeling

hydrodynamic behavior of an airlift reactor with net draft tube with different configurations: Numerical evaluation using CFD technique

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Particuology 2020年第4期18卷 91-108页

作者： Reza Salehpour Elham Jalilnejad Mehran Nalband Kamran ghasemzadeh Faculty of Chemical Engineering Urmia University of TechnologyUrmiaIran

In terms of gas holdup,liquid velocity,and volumetric mass transfer coefficient for oxygen(KLa),the hydrodynamic behavior of four configurations of an airlift reactor(ALR)with a net draft tube(NDT)of different net mesh sizes(ALR-NDT-3,6,12,and ALR)have been numerically simulated for a range of inlet air flow *** effect of various levels of ratio of height(h)to inner tube diameter(D)of the net draft tube(h/D:9.3,10.7,17.5,and 20)and ratio of inner cross-sectional area of the riser(Ar)to the inner cross sectional area of the downcomer(Ad)(Ad/Ar:1.3 and 7)for different air flow rates is also evaluated for each reactor configuration operating with an air-water *** two-fluid formulation coupled with the k-εturbulence model is used for computational fluid dynamics(CFD)analysis of flow with Eulerian descriptions for the gas and liquid *** between air bubbles and liquid are taken into account using momentum exchange and drag coefficient based on two different *** in the predicted dynamical behavior are similar to those found experimentally.A good agreement was achieved suggesting that geometric effects are properly accounted for by the CFD *** a comparison with experimental data,numerical simulations show significant enhanced gas holdup,liquid velocity,and Kta for the ALR-NDTs compared with the conventional *** gas holdup values are achieved for ALR-NDT-3 than that for the other ALRs because it acts like a bubble column reactor as the holes present in the NDT are *** liquid velocities are seen in ALR-NDT-12,which operates like a conventional ***,the interaction between the NDT and upward gas flow leads to cross flow through the net,small bubbles,and high interfacial area as well as good mass *** was significant in ALR-NDT-6 with maximum Kta value of 0.031 *** applied methodology provides an insightful understanding of the complex dynamic behavior of ALR-NDTs and may be helpful in op

关键词： Airlift reactor Net draft tube hydrodynamic behavior Computational fluid dynamics(CFD) Gas holdup Mass transfer coefficient

Full Polysaccharide Crosslinked-chitosan and Silver Nano Composites, for Use as an Antibacterial Membrane

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Chinese Journal of Polymer Science 2016年第8期34卷 949-964页

作者： hossein ghasemzadeh Mahdieh Sheikhahmadi Fatemeh Nasrollah Department of chemistry Imam Khomeini International University

Full polysaccharide crosslinked-chitosan membranes were prepared by crosslinking of chitosan with chitosan dialdehyde followed by reduction with sodium borohydride. Partially oxidized chitosan, generated from periodate oxidation of chitosan, was used as a crosslinker. The modulus values and elongation at break were increased with increasing the crosslinker weight ratio. The rheological measurements showed that depolymerization of chitosan can take place rapidly in the presence of the oxidizing agent. The weight reduction of crosslinked-chitosan membrane after 12 h, at ph = 4 and ph = 2 was found to be 85.0% and 90.0%, respectively. The structure of the crosslinked-chitosan and the silver nanocomposite were confirmed by FTIR spectroscopy, scanning electron microscopy （SEM）, and thermogravimetric analysis （TGA）. Transmission electron microscopy （TEM） reveals the presence of well-separated Ag nanoparticles with diameters in the range of 4-10 nm. The silver ion loading increases with increasing the silver ion concentration, and decreasing the crosslink density. The MBC/MIC ratio of 2.0, 2.0, and 1.0 was achieved for E. coli, S. aureus, and P. aeruginosa, respectively.

关键词： Silver nanocomposites Chitosan Crosslinking Antibacterial effects.

Physical Simulation of hot Deformation and Microstructural Evolution for 42CrMo4 Steel Prior to Direct Quenching

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Journal of Iron and Steel Research International 2009年第6期16卷 47-51页

作者： A h Meysami R ghasemzadeh S h Seyedein M R Aboutalebi R Ebrahimi M Javidani Department of Material Science and Engineering Iran University of Science and Technology Department of Material Science and Engineering Sabzevar Tarbiat-Moallem University

Direct quenching and tempering （DQ-T） of hot rolled steel section has been widely used in steel mill for the sake of improvement of mechanical properties and energy saving. Temperature history and microstructural evolution during hot rolling plays a major role in the properties of direct quenched and tempered products. The mathematical and physical modeling of hot forming processes is becoming a very important tool for design and development of required products as well as predicting the microstructure and the properties of the components. These models were mostly used to predict austenite grain size （AGS）, dynamic, recta-dynamic and static recrystallization in the rods immediately after hot rolling and prior to DQ process. The hot compression tests were carried out on 42CrMo4 steel in the temperature range of 900-1 100 ℃ and the strain rate range of 0. 05-1 s^-1 in order to study the high tempera- ture softening behavior of the steel. For the exact prediction of flow stress, the effective stress-effective strain curves were obtained from experiments under various conditions. On the basis of experimental results, the dynamic recrystallization fraction （DRX）, AGS, hot deformation and activation energy behavior were investigated. It was found that the calculated results were in good agreement with the experimental flow stress and microstructure of the steel for different conditions of hot deformation.

关键词： 42CrMo4 steel hot compression test dynamic recrystallization hot deformation direct quenching physical simulation

Zinc oxide nanoparticles:A highly efficient and readily recyclable catalyst for the synthesis of xanthenes

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Chinese Chemical Letters 2012年第11期23卷 1225-1229页

作者： Javad Safaei-Ghomi Mohammad Ali ghasemzadeh Department of Organic Chemistry Faculty of ChemistryUniversity of Kashan

A novel and efficient route for the synthesis of 1,8-dioxooctahydroxanthenes and 14-aryl-14h-dibenzo[a,j]xanthenes is described through one-pot multi-component reaction of dimedone and 2-naphthol with various aryl aldehydes using ZnO nanoparticles under solvent-free conditions. This method provides a novel and improved pathway for the synthesis of xanthenes in the terms of excellent yields, short reaction times, reusability and low catalyst loading.

关键词： ZnO nanoparticles Xanthene Solvent-free Multi-component reaction heterogeneous catalysts

Effect of Sulfur Precursor on Dimensions of One-dimensional CdS Nanocrystals

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Journal of Materials Science & Technology 2009年第4期25卷 462-464页

作者： M.Maleki Sh.Mirdamadi R.ghasemzadeh M.Sasani Ghamsari Department of Metallurgy and Material Engineering Iran University of Science & Technology Solid State Lasers Research Group Laser & Optics Research School

One-dimensional CdS nanocrystals have been prepared by solvothermal method using cadmium acetate as a cadmium precursor, elemental sulfur and Na2S, as a sulfur precursor, and ethylenediamine as a solvent at 150℃ for 5 h. The nanocrystals were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and UV-Vis absorption spectroscopy. XRD patterns indicate that both Na2S and elemental sulfur as the sulfur precursor result in CdS nanorods with wutzite phase （hexagonal structure）. SEM and TEM images show that diameter of CdS nanorods can be decreased using Na2S instead of elemental sulfur. For the growth of CdS nanorods, a mechanism has been proposed. Uv-Vis absorption of CdS nanorods （sulfur precursor： Na2S） was shown blue shift to 485 nm due to the quantum size effect.

关键词： Nanomaterials Semiconductors CdS nanorods Na2S Solvothermal method

A comparison of the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women:A randomized controlled trial

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Journal of Integrative Nursing 2023年第1期5卷 21-26页

作者： Tahereh BEhROUZI LAK Nader AGhAKhANI Davoud VAhABZADEh Samereh EGhTEDAR Rozita ChERAGhI Nazafarin ghasemzadeh Vahid ALINEJAD Maryam MESGARZADEh Reproductive health Research Center Urmia University of Medical SciencesUrmiaIran Food and Beverages Safety Research Center Urmia University of Medical SciencesUrmiaIran Department of Nutrition and Biochemistry Faculty of MedicineIlam University of Medical SciencesIlamIran Department of Medical Surgical Nursing School of Nursing and MidwiferyUrmia University of Medical SciencesUrmiaIran Department of Medical Ethics Faculty of MedicineUrmia University of Medical SciencesUrmiaIran Department of Biostatics Faculty of MedicineUrmia University of Medical SciencesUrmiaIran Department of Midwifery School of Nursing and MidwiferyUrmia University of Medical SciencesUrmiaIran

Objective:The aim of this study is to compare the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women who were referred to the Kowsar gynecological clinics of Shahid Motahari hospital of Urmia University of Medical *** and Methods:A double-blinded clinical trial was conducted on 112 women with dysmenorrhea who were randomly allocated into the four study ***,100 women complete the study and received capsules containing a placebo(n=25),1000 IU of Vitamin D(n=25),400 mg of Vitamin E(n=25),and 1000 IU of Vitamin D+400 mg of Vitamin E(n=25)every 24 h for 2 consecutive months at the beginning of the menstrual *** pain intensity and duration among groups were compared before and after the ***:The mean menstrual pain duration in all three experimental groups(Vitamin E,Vitamin D,and the combination of them)was lower than the placebo group(all Phe mean pain intensity scores in all three experimental groups were significantly lower than the placebo group(all Phe results(means)for all of the drugs administered at the end of the 2nd month were better than the 1st month(all Pheir combination,are recommended as an effective and safe treatment for the management of the complications of dysmenorrhea.

关键词： Duration dysmenorrhea intensity randomized controlled trial Vitamin D Vitamin E women

新的氧化应激标志物与冠状动脉疾病患者的死亡风险相关

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中华高血压杂志 2015年第11期23卷 1079-1079页

作者：刘莉叶鹏 Patel RS ghasemzadeh N Eapen DJ Sher S Arshad S Ko YA Veledar E Samady h Zafari AM Sperling L Vaccarino V Jones DP Quyyumi AA

该文旨在验证新出现的以氨基硫醇为标志物的非自由基介导的氧化应激与临床预后的关系。方法：纳入行冠状动脉造影的1411例患者（平均63岁,男性占66%）,应用高效液相色谱仪定量分析还原的（半胱氨酸和谷胱甘肽）和氧化的（半胱氨酸和谷... 详细信息

该文旨在验证新出现的以氨基硫醇为标志物的非自由基介导的氧化应激与临床预后的关系。方法：纳入行冠状动脉造影的1411例患者（平均63岁,男性占66%）,应用高效液相色谱仪定量分析还原的（半胱氨酸和谷胱甘肽）和氧化的（半胱氨酸和谷胱甘肽二硫化物）氨基硫醇水平。

关键词：氧化应激高效液相色谱仪谷胱甘肽死亡风险炎症因子水平全因死亡率协变量