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Effect of 2-mercaptobenzothiazole concentration on sour-corrosion behavior of API X60 pipeline steel:Electrochemical parameters and adsorption mechanism

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 271-282页

作者： Masoud Sabzi Amir Hayati Jozani Farzad Zeidvandi Majid Sadeghi saeid Mersagh Dezfuli Young Researchers and Elite Club Dezful BranchIslamic Azad UniversityDezfulIran Department of Materials Science and Engineering Science and Research BranchIslamic Azad UniversityTehranIran Center of Excellence for Surface Engineering and Corrosion Protection of Industrial School of Metallurgy and Materials EngineeringCollege of EngineeringUniversity of TehranP.O.Box 11155-4563TehranIran

We investigated the effect of the 2-mercaptobenzothiazole concentration on the sour-corrosion behavior of API X60 pipeline steel in an environment containing H_(2)S at 25°C and in the presence of 0,2.5,5.0,7.5,and 10.0 g/L of 2-mercaptobenzothiazole *** examine this behavior,we conducted open-circuit potential(OCP),potentiodynamic polarization,and electrochemical impedance spectroscopy(EIS)*** dispersive spectroscopy and scanning electron microscopy were also used to analyze the corrosion *** results of the OCP and potentiodynamic polarization tests revealed that 2-mercaptobenzothiazole reduces the speed of both the anodic and cathodic *** assessment of the Gibbs free energy of the inhibitor(△G_(ads)^(■))indicated that its value was less than-20 kJ·mol^(-1)and greater than-40 k J·mol^(-1).Therefore,the adsorption of 2-mercaptobenzothiazole onto the surface of the API X60 pipeline steel occurs both physically and chemically,the latter of which is particularly *** addition,as the△G_(ads)^(■)dsvalue was negative,we could conclude that the adsorption of 2-mercaptobenzothiazole onto the surface of the pipeline steel occurs *** EIS results indicate that with the increase in the 2-mercaptobenzothiazole inhibitor concentration,the corrosion resistance of API X60 steel *** analysis of the corrosion products revealed that iron sulfide compounds form on the *** summary,the results showed that an increase in the inhibitor concentration results in a decrease in the corrosion rate and an increase in inhibitory ***,we found that the 2-mercaptobenzothiazole adsorption process on the API X60 steel surfaces in an H2 S-containing environment follows the Langmuir adsorption isotherm and occurs spontaneously.

关键词： API X60 steel sour corrosion 2-mercaptobenzothiazole inhibitor concentration electrochemical parameters environments containing hydrogen sulfide

Thermal Transport in Nanoporous Yttria-Stabilized Zirconia by Molecular Dynamics Simulation

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Journal of Shanghai Jiaotong university(Science) 2018年第1期23卷 38-44页

作者：赵帅帅邵成 ZAHIRI saeid 赵长颖鲍华 University of Michigan-Shanghai Jiao Tong University Joint Institute School of Mechanical and Power Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Yttria-stabilized zirconia(YSZ) is widely used as thermal barrier coatings(TBCs) to reduce heat transfer between hot gases and metallic components in gas-turbine engines. Porous structure can generally reduce the lattice thermal conductivity of bulk material, so porous YSZ can be potentially used as TBCs with better thermal performance. In this work, we investigate the thermal conductivity of nanoporous YSZ using the nonequilibrium molecular dynamics(NEMD) simulation, and comprehensively discuss the effects of cross-sectional area, pore size, structure length, porosity, Y_2O_3 concentration and temperature on the thermal conductivity. To compare with the results of the NEMD simulation, we solve the heat diffusion equation and the gray Boltzmann transport equation(BTE) to calculate the thermal conductivity of the same porous structure. From the results,we find that the thermal conductivity of YSZ has a weak dependence on the structure length at the length range from 10 to 26 nm, which indicates that the majority of heat carriers have very short mean free path(MFP) but there exists small percentage(about 3%) of phonons with longer MFP(larger than 10 nm) contributing to the thermal conductivity. The thermal conductivity predicted by NEMD simulation is smaller than that of solving heat diffusion equation(diffusive limit) with the same porous structure. It shows that the presence of pores affects phonon scattering and further affects the thermal conductivity of nanoporous YSZ. The results agree well with the solution of gray BTE with a average MFP of 0.6 nm. The thermal conductivity of nanoporous YSZ weakly depends on the Y_2O_3 concentration and temperature, which shows the phonons with very short MFP play the major contribution to the thermal conductivity. The results help to better understand the heat transfer in porous YSZ structure and develop better TBCs.

关键词： thermal conductivity nanoporous molecular dynamics mean free path(MFP) yttria-stabilized zirconia(YSZ)

A state-of-the-art review of the fabrication and characteristics of titanium and its alloys for biomedical applications

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Bio-Design and Manufacturing 2022年第2期5卷 371-395页

作者： Masoud Sarraf Erfan Rezvani Ghomi saeid Alipour Seeram Ramakrishna Nazatul Liana Sukiman Centre of Advanced Materials Department of Mechanical EngineeringFaculty of EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia Department of Materials Science and Engineering Sharif University of TechnologyAzadi Ave.P.O.Box 11365‑9466TehranIran Center for Nanotechnology and Sustainability Department of Mechanical EngineeringNational University of SingaporeSingapore 117581Singapore

Commercially pure titanium and titanium alloys have been among the most commonly used materials for biomedical applications since the 1950 *** to the excellent mechanical tribological properties,corrosion resistance,biocompatibility,and antibacterial properties of titanium,it is getting much attention as a biomaterial for ***,titanium promotes osseointegration without any additional adhesives by physically bonding with the living bone at the implant *** properties are crucial for producing high-strength metallic alloys for biomedical *** alloys are manufactured into the three types ofα,β,andα+β.The scientific and clinical understanding of titanium and its potential applications,especially in the biomedical field,are still in the early *** review aims to establish a credible platform for the current and future roles of titanium in *** first explore the developmental history of ***,we review the recent advancement of the utility of titanium in diverse biomedical areas,its functional properties,mechanisms of biocompatibility,host tissue responses,and various relevant antimicrobial *** research will be directed toward advanced manufacturing technologies,such as powder-based additive manufacturing,electron beam melting and laser melting deposition,as well as analyzing the effects of alloying elements on the biocompatibility,corrosion resistance,and mechanical properties of ***,the role of titania nanotubes in regenerative medicine and nanomedicine applications,such as localized drug delivery system,immunomodulatory agents,antibacterial agents,and hemocompatibility,is investigated,and the paper concludes with the future outlook of titanium alloys as biomaterials.

关键词： Titanium and titanium alloys Biomedical application Functional properties Biocompatibility Antibacterial activity Advanced manufacturing

The Influence of Bridge Type on the Activity of Supported Metallocene Catalysts in Ethylene Polymerization

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Chinese Journal of Polymer Science 2014年第2期32卷 137-142页

作者： Alireza Talaei Faramarz Afshar Taromi Ahmad Arefazar saeid Ahmadjo Omid Moini Jazani Department of Polymer Engineering and Color Technology Amirkabir University of Technology Department of Catalyst Iran Polymer and Petrochemical Institute (IPPI) Department of Chemical Engineering College of Engineering University of Isfahan

Ethylene polymerization was carried out by immobilization of rac-ethylenebis（1-indenyl）zirconium dichloride （Et（Ind）2ZrCl2） and rac-dimethylsilylbis（1-indenyl）zirconium dichloride （Me2Si（Ind）2ZrCl2） preactivated with methylaluminoxane （MAO） on calcinated silica at different temperatures. Polymerizations of ethylene were conducted at different temperatures to find the optimized polymerization temperature for maximum activity of the catalyst. The Me2Si bridge catalyst showed higher activity at the lower polymerization temperature compared to the Et bridge catalyst. The highest catalytic activities were obtained at temperatures about 50 ~C and 70 ~C for Me2Si（Ind）2ZrC1JMAO and Et（Ind）zZrCI2/MAO catalysts systems, respectively. Inductively coupled plasma-atomic emission spectroscopy results and polymerization activity results confirmed that the best temperature for calcinating silica was about 450 ℃ for both catalysts systems. The melting points of the produced polyethylene were about 130 ℃, which could be attributed to the linear structure of HDPE.

关键词： Slurry polymerization Olefin polymerization ansa-Metallocene Silica support.

Pricing System Design for Airport Parking Project Case Study:Imam Khomeini International Airport

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Pricing System Design for Airport Parking Project Case Study...

作者： saeid JAMEI 山东大学

学位级别：硕士

近年来,大型机场造成的停车位不足和交通拥堵为许多人造成了障碍。因为机场这部分的中断导致机场其他部分的运行失败,因此降低了机场的服务水平。由于缺乏停车位,在路边可以找到交通,这会引起其他问题。例如晚到航班甚至失去航班。每个... 详细信息

近年来,大型机场造成的停车位不足和交通拥堵为许多人造成了障碍。因为机场这部分的中断导致机场其他部分的运行失败,因此降低了机场的服务水平。由于缺乏停车位,在路边可以找到交通,这会引起其他问题。例如晚到航班甚至失去航班。每个机场的管理者和计划者都应了解世界上其他机场当前使用的泊车类型,以提供合适的泊车位,以使旅客和会客和迎宾员感到舒适。停车收费是最常见的管理策略之一,它会影响停车需求并管理高停车需求问题。由于用户意见的重要性以及该策略对他们选择方法的直接影响,本研究提出了用于获取信息以支付模型费用的偏好状态方法。此外,为了应对长期（开放式）停车的这些变化,对伊玛目霍梅尼国际机场的乘客给予了优惠待遇。这些数据是通过对377种不同价格情景的问卷进行访谈而收集的,每个问卷包含7种选择。在使用该软件建模并制作了二进制logit,嵌套模型和多个模型之后,最终将对二进制和多个logite模型进行分析以获得结果。嵌套逻辑模型应与Ⅳ参数的值成比例小于1。为了更精确地建模,取决于模型条件,必须将其中一个嵌套的Ⅳ设置为1。在此模型中,此操作是针对嵌套停车场执行的。重复此操作后,其他嵌套的输出未进行任何更改。因此,无法确认选项嵌套行为的假设,最后,由于通过了Ⅳ参数测试,因此不使用经过处理的嵌套模型,并且可以通过破坏嵌套来使用多重logit模型。多重logit模型的结果表明,如果将停车价格提高到20,000 Tomans①,则选择停车场的可能性将降低30%,并且与使用私家车（由朋友和熟人开车）相比,该可能性会增加30%。12%,出租车16%,出租车22%,地铁8%。

关键词：机场停车停车价格二进制logit 多次logit 嵌套logit

Predicting hydrate forming pressure of pure alkanes in the presence of inhibitors

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Journal of Natural Gas Chemistry 2008年第3期17卷 249-255页

作者： Alireza Bahadori Hari B.Vuthaluru saeid Mokhatab Moses O.Tade Department of Chemical Engineering Curtin University of Technology Process Technology Department Tehran Raymand Consulting Engineers

An inherent problem with natural gas production or transmission is the formation of gas hydrates, which can lead to safety hazards for production/transportation systems, and substantial economic risks. Hydrate inhibition with different inhibitors such as, methanol, ethylene glycol （EG）, triethylene glycol （TEG）, and sodium chloride solution continues to play a critical role in many operations. An understanding of when the hydrates form in the presence of these hydrate inhibitors, is therefore necessary to overcome hydrate problems. Several thermodynamic models have been proposed for predicting the hydrate formation conditions in aqueous solutions containing methanol/glycols and electrolytes. However, available models have limitations that include the types of liquid, compositions of fluids, and inhibitors used. The aim of this study is to develop a simple-to-use correlation for accurate prediction of hydrate-forming pressures of pure alkanes in the presence of different hydrate inhibitors, where the obtained results illustrate good agreement with the reported experimental data.

关键词： gas hydrates pure alkanes methanol: ethylene glycol triethylene glycol sodium chloride

Effect of graphene oxide on the corrosion,mechanical and biological properties of Mg-based nanocomposite

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 305-319页

作者： saeid Jabbarzare Hamid Reza Bakhsheshi-Rad Amir Abbas Nourbakhsh Tahmineh Ahmadi Filippo Berto Department of Materials Science Shahreza BranchIslamic Azad UniversityShahrezaIran Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Department of Mechanical and Industrial Engineering Norwegian University of Science and Technology7491 TrondheimNorway

This study investigates the effect of graphene oxide(GO)on the mechanical and corrosion behavior,antibacterial performance,and cell response of Mg–Zn–Mn(MZM)***/GO nanocomposites with different amounts of GO(i.e.,0.5 wt%,1.0 wt%,and1.5 wt%)were fabricated by the semi-powder metallurgy *** influence of GO on the MZM nanocomposite was analyzed through the hardness,compressive,corrosion,antibacterial,and cytotoxicity *** experimental results showed that,with the increase in the amount of GO(0.5 wt%and 1.5 wt%),the hardness value,compressive strength,and antibacterial performance of the MZM nanocomposite increased,whereas the cell viability and osteogenesis level decreased after the addition of 1.5 wt%***,the electrochemical examination results showed that the corrosion behavior of the MZM alloy was significantly enhanced after encapsulation in 0.5 wt%*** summary,MZM nanocomposites reinforced with GO can be used for implant applications because of their antibacterial performance and mechanical property.

关键词： magnesium-based nanocomposite graphene oxide powder metallurgy method mechanical property antibacterial activity biocompatibility

The impact of land afforestation on carbon stocks surrounding Tehran,Iran

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Journal of Forestry Research 2014年第1期25卷 135-141页

作者： saeid Varamesh Seyyed Mohsen Hosseini Farshad Keivan Behjou Ebrahim Fataei Department of Forestry Faculty of Natural ResourcesTarbiat Modares University Department of Environmental engineering Ardabil BranchIslamic Azad University Faculty of Agricultural Technology and Natural Resources University of Mohaghegh Ardabili

The city of Tehran, like many polluted metropolises of the world, has higher emissions of greenhouse gases than other cities in Iran, due to heavy consumption of fossil fuel and landuse changes. To estimate carbon sequestration in two 40 year-old stands of plantedCupressus arizonica andFraxinus rotundifolia in degraded lands surrounding Tehran , sampling of above- and below- ground biomass, soil （at two depths of 0-15 and 15-30 cm）, and leaf litter was done by systematic random sampling. The total carbon stocks ofC. arizonica and F. rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1. The aboveground biomass with 233.16（71%） Mg·ha-1 inC. arizonica and 88.16 （58.50%） Mg·ha-1 inF. rotundifolia contributed the most shares to carbon sequestration. The diameter at breast height, total height, basal area, total volume, and biomass ofC. arizonica were significantly （p 〈0.01） higher than those ofF. rotundifolia. Also the depth of 0-30 cm of soil contributed between 18.29 % and 32.15 % of total ecosystem carbon, respectively. The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars, respectively. Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land, the current status quo. These stands can absorb atmospheric CO2at different rates, thus tree species selection and stand development should be considered in planning future afforestation projects.

关键词： carbon sequestration afforestation Cupressus arizonica Fraxinus rotundifolia Tehran.

Improvement of the prediction performance of a soft sensor model based on support vector regression for production of ultra-low sulfur diesel

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Petroleum Science 2015年第1期12卷 177-188页

作者： saeid Shokri Mohammad Taghi Sadeghi Mahdi Ahmadi Marvast Shankar Narasimhan Department of Chemical Engineering Iran University of Science and Technology (IUST) Process and Equipment Technology Development Division Research Institute of Petroleum Industry (RIPI) Department of Chemical Engineering

A novel data-driven, soft sensor based on support vector regression （SVR） integrated with a data compression technique was developed to predict the product quality for the hydrodesulfurization （HDS） process. A wide range of experimental data was taken from a HDS setup to train and test the SVR model. Hyper-parameter tuning is one of the main challenges to improve predictive accuracy of the SVR model. Therefore, a hybrid approach using a combination of genetic algorithm （GA） and sequential quadratic programming （SQP） methods （GA-SQP） was developed. Performance of different optimization algorithms including GA-SQP, GA, pattern search （PS）, and grid search （GS） indicated that the best average absolute relative error （AARE）, squared correlation coefficient （R2）, and computation time （CT）（AARE = 0.0745, R2 = 0.997 and CT = 56 s） was accomplished by the hybrid algorithm. Moreover, to reduce the CT and improve the accuracy of the SVR model, the vector quantization （VQ） technique was used. The results also showed that the VQ technique can decrease the training time and improve prediction performance of the SVR model. The proposed method can provide a robust, soft sensor in a wide range of sulfur contents with good accuracy.

关键词： Soft sensor Support vector regression Hybrid optimization method Vector quantization Petroleum refinery Hydrodesulfurization process Gas oil