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Advanced development in upstream of petroleum industry using nanotechnology

Chinese Journal of Chemical Engineering 2020年第6期28卷 1483-1491页

作者： Sedigheh sadegh Hassani Maryam Daraee Zahra Sobat Catalysis research Division Research Institute of Petroleum Industry(RIPI)West Entrance Blvd.Olympic VillageP.O.Box 14857-33111TehranIran Nanotechnology Research Center Research Institute of Petroleum Industry(RIPI)West Entrance Blvd.Olympic VillageP.O.Box 14857-33111TehranIran

Nowadays,energy supply is one of the most important issues due to limitation of oil,gas and coal *** of rapid population,civilization and energy consumption growth,the improved technologies to make optimal use of the sources,solving related problems and finding new energy sources are *** than 10 years ago,nanotechnology as one of the most important technologies has also been applied to progress in the oil and gas industry(upstream,midstream and downstream).The experience of these years has shown that application of nanotechnology in the oil industry improves the exploration of crude oil and natural gas(underground or deep water),drilling and bringing the crude oil or raw natural gas to the surface,as well as transportation,storage,processing and purifying *** with high specific surface area,pore volume and small size show unique physical and chemical properties,which could be applied in several *** this regard,many researchers have been focused on various nanoparticles for upstream industries and studied their potential in oil exploration,drilling,production and enhanced oil recovery(EOR).Also,in downstream and midstream which involve refining of crude oil,processing and purifying of raw natural gas,transportation and storage of crude or refined petroleum products,the nanomaterials have been used to improve the quality of oil and make it appropriate for the *** sulfur gasoline,enhancing the octane number and coating the transportation system are among the goals that have been achieved successfully using *** this work,various types of nanoparticles such as metallic,metal oxide,hybrid nanoparticles,carbon nanomaterials,nano-composites and their applications in oil upstream industry are ***,their usage in different types of oil upstream processes is discussed.

关键词： Nanotechnology Oil exploration Oil drilling Nanoparticles Enhanced oil recovery

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Effects of die geometry on non-equal channel lateral extrusion(NECLE) of AZ80 magnesium alloy

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Transactions of Nonferrous Metals Society of China 2014年第10期24卷 3274-3284页

作者： Faramarz FERESHTEH-SANIEE mohammad asgari Mahmoud BARATI Sayed Mahmoud PEZESHKI Mechanical Engineering Department Faculty of Engineering Bu-Ali Sina University Applied Mechanics Department Faculty of Mechanical Engineering K.N. Toosi University of Technology

Non-equal channel lateral extrusion（NECLE） is a new process that can be used to attain higher grain refinement in comparison with equal channel lateral extrusion（ECLE）. The die design for this process was numerically and experimentally studied. After finding a good correlation between the numerical and experimental results, more comprehensive FE analyses were carried out. Different die geometrical parameters were considered and their effects on the induced plastic strain, stress distribution, velocity field and forming load of the process were investigated. It was found that by this process with a suitable set of die geometrical parameters, higher induced effective strain and more homogeneous strain distribution could be achieved in comparison with ECLE operation.

关键词： magnesium alloy non-equal channel lateral extrusion(NECLE) die geometry homogeneity arbitrary Lagrangian-Eulerian(ALE) method

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Colonoscopic evaluation of minimal rectal bleeding in average-risk patients for colorectal cancer

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World Journal of Gastroenterology 2008年第42期14卷 6536-6540页

作者： Shahriar Nikpour Ali Ali asgari Department of InternalMedicine Loghman Hakim Hospital Shaheed BeheshtiUniversity of Medical Sciences Tehran Iran

AIM: To assess the prevalence of clinically signifi cant lesions in patients with minimal bright red bleeding per rectum (BRBPR). METHODS: Consecutive outpatients prospectively underwent colonoscopy at Loghman Hakim Hospital, Tehran. Minimal BRBPR was defi ned as small amounts of red blood after wiping or in the toilet bowl. Patients with the following alarm signs were excluded: Positive personal history of colorectal neoplasms or inflamma-tory bowel disease (IBD), positive fi rst degree family history of colorectal neoplasms, history of altered bow- el habits, recent signifi cant weight loss, and presence of iron defi ciency anemia. Neoplastic polyps, colorectal carcinoma, and IBD were def ined as signif icant lesions. RESULTS: A total of 402 patients (183 female and 219 male, aged 43.6 ± 15.7 years) were studied. Hemorrhoids (54.2%), anal fi ssures (14.2%) and ul-cerative colitis (14.2%) were the most common lesions and colonoscopy was normal in 8.0%. Signifi cant le-sions were found in 121 (30.1%) patients, including 26 patients (6.5%) with adenocarcinoma and 30 (7.5%) with adenomatous polyps. Almost all patients with signifi cant lesions had at least one lesion in the distal colon; an adenocarcinoma and an adenomatous polyp in the proximal colon were found in 2 patients with hemorrhoids. CONCLUSION: Flexible sigmoidoscopy appears to be sufficient for the evaluation of average risk patients with minimal BRBPR. Rigid sigmoidoscopy may be used as an alternative in patients less than 40 years of age in settings where the former is not available. Thechoice of colonoscopy over flexible sigmoidoscopy in patients aged over 50 years should be individualized.

关键词： Gastrointestinal hemorrhage Colonoscopy Colorectal neoplasms Inflammatory bowel disease

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Cryptanalysis of DBST, a lightweight block cipher

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Frontiers of Computer Science 2024年第4期18卷 219-221页

作者： sadegh sadeghI Nasour BAGHERI Department of Mathematics Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Research Center for Basic Sciences and Modern Technologies(RBST) Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Electrical Engineering Department Shahid Rajaee Teacher Training UniversityTehran 16788-15811Iran School of Computer Science(SCS) Institute for Research in Fundamental Sciences(IPM)Tehran 19395-5531Iran

1 Introduction Conventional cryptographic primitives are not suitable for resource-constrained ***,numerous lightweight primitives have been proposed over the past decade,specifically tailored for such ***,such ciphers would not be used in a real-world application unless they were thoroughly tested for security against existing *** this direction,DBST[1]cipher has been recently proposed by Yan et *** balance security,cost,and efficiency,DBST has implemented a novel 4-branch generalized Feistel variant *** this structure,a 2-branch XOR operation has been incorporated in the middle section,establishing interconnections between all *** the other hand,by leveraging the bit-slice technique and subkeys,the algorithm introduces an innovative approach to constructing a dynamic S-box *** designers of DBST cipher have extensively investigated its resistance to known attacks such as linear and differential cryptanalysis,as well as impossible differential cryptanalysis,among *** them,the objective of differential cryptanalysis[2]is to identify high-probability characteristics in the plaintext that are transmitted to the ciphertext,known as distinguishers.

关键词： structure. primitive branch

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Tunable graphene-based mid-infrared band-pass planar filter and its application

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Chinese Physics B 2018年第8期27卷 290-296页

作者： Somayyeh asgari Hossein Rajabloo Nosrat Granpayeh Homayoon Oraizi Center of Excellence in Electromagnetics Optical Communication Laboratory Faculty of Electrical EngineeringK N Toosi University of Technology Young Researchers and Elite Club Azadshahr Branch Islamic Azad University Department of Electrical Engineering Iran University of Science and Technology

We have designed and proposed the edge modes supported by graphene ribbons and the planar band-pass filter consist- ing of graphene ribbons coupled to a graphene ring resonator by using the finite-difference time-domain numerical method. Simulation results show that the edge modes improve the electromagnetic coupling between devices. This structure works as a novel, tunable mid-infrared band-pass filter. Our studies will benefit the fabrication of planar, ultra-compact nano-scale devices in the mid-infrared region. A power splitter consisting of two output ribbons that is useful in photonic integrated devices and circuits is also designed and simulated. These devices are useful for designing ultra-compact planar devices in photonic integrated circuits.

关键词： band-pass filter graphene surface plasmons power splitter

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Line-start permanent magnet synchronous motors versus induction motors： A comparative study

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Frontiers of Electrical and Electronic Engineering in China 2012年第4期7卷 459-466页

作者： Majid Ghasemi KAHRISANGI Arash Hassanpour ISFAHANI sadegh VAEZ-ZADEH mohammad Rajabi SEBDANI SAMA Technical and Vocational College Islamic Azad UniversityKhomeinishahr Branch Isfahan Iran Department of Engineering Islamic Azad University KhomeinishahrBranch Isfahan Iran School of Electrical and Computer Engineering University of TehranTehran Iran Department of'Engineering Islamic Azad University Harand BranchIsfahan Iran

Line-start permanent magnet synchronous motors are suitable candidates for substitution of induction motors in many constant-speed applications. This paper compares steady-state and dynamic performances of these motors. The efficiency, power factor, stator currents, and rotor bars currents are considered for steady-state perfor- mance analysis whereas the rotor speed, electromagnetic torque, and stator and rotor currents are investigated for dynamic performance analysis. For this purpose, time stepping finite element method is used to analyze the performance of motors in both full-load and no-load conditions. Results demonstrate the superior performance of the line-start permanent magnet synchronous motor in steady-state condition and the improved dynamic perfor-mance of the induction motor. Finally, economic calcula- tions indicate that the extra cost of the line-start permanent magnet synchronous motor with respect to the induction motor is rapidly compensated by energy saving due to a more efficient operation.

关键词： line-start permanent magnet synchronous

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Formation evaluation and rock type classification of Asmari Formation based on petrophysical-petrographic data:A case study in one of super fields in Iran southwest

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Petroleum 2023年第2期9卷 143-165页

作者： Raeza Mirzaee Mahmoodabadi sadegh Zahiri Department of Geology Estahban BranchIslamic Azad UniversityEstahbanIran National Iranian South Oil Company(NISOC) AhvazIran

The Oligo-Miocene Asmari Formation is one of the most important hydrocarbon reservoirs in the Middle *** oilfield under study is one of the largest oilfields in the Zagros basin with the Asmari Formation being the major reservoir *** this study,petrographic analyses,petrophysical data and neural network clustering techniques were used for identifying rock types in the Asmari *** analysis of the Asmari Formation in the study area has resulted in the definition of 1 clastic lithofacies and 14 carbonate microfacies *** petrophysical logs from 43 wells and their correlation with capillary pressure(Pc)curves,led to the recognition of 7 electrofacies(EF1-EF7).Microscopic evidence of Electrofacies group C1 and S1 show that the sedimentary facies of these electrofacies are most commonly found in restricted and shoal facies belts ***,petrographic studies show that the sedimentary facies of C2,C3,C4,S2 and S3 were formed in the open marine,Lagoon,and Tidal flat facies belt zone of homoclinal ramp sedimentary environment during the Oligo-Miocene based on relative sea level changes *** link between electrofacies and geological data indicated that both sedimentary and diagenetic processes controlled the reservoir quality of the Asmari ***,permeability and water saturation were used to estimate the reservoir quality of each *** 1 and 2 with high porosity and permeability,low water saturation is considered as the best reservoir with regard to sedimentary textures(dolowackestone and dolograinstone)and the effect of diagenetic processes such as dolomitization ***,growth framework and interparticle porosities are major in EF-2,while the intercrystalline porosity is the major type in *** 3 and 4 show low values of porosity,permeability and high percentage of water saturations,which characterizes them as poor reservoir ***,EF-5 is the only electrofacies in the siliciclastic parts of

关键词： Asmari formation Electrofacies Petrophysical log Rock typing Zagros basin

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Combination of sensitivity and uncertainty analyses for sediment transport modeling in sewer pipes

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International Journal of Sediment Research 2020年第2期35卷 157-170页

作者： Isa Ebtehaj Hossein Bonakdari Mir Jafar sadegh Safari Bahram Gharabaghi Amir Hossein Zaji Hossien Riahi Madavar Zohreh Sheikh Khozani mohammad sadegh Es-haghi Aydin Shishegaran Ali Danandeh Mehr Department of Civil Engineering Razi University Environmental Research Center Razi University Department of Civil Engineering Yasar University 4. School of EngineeringUniversity of Guelph 5. Department of Water EngineeringVali-e-Asr University of Rafsanjan 6. Smart and Sustainable Township Research CenterFaculty of Engineering&Built EnvironmentUniversiti Kebangsaan Malaysia 7. School of Civil EngineeringK.N.Toosi University of Technology 8. Department of Waterand EnvironmentalIran University of Science and Technology 9. Department of Civil EngineeringAntalya Bilim University

Mitigation of sediment deposition in lined open channels is an essential issue in hydraulic engineering ***,the limiting velocity should be determined to keep the channel bottom clean from sediment ***,sediment transport modeling using various artificial intelligence(AI) techniques has attracted the interest of many *** current integrated study highlights unique insight for modeling of sediment transport in sewer and urban drainage systems.A novel methodology based on the combination of sensitivity and uncertainty analyses with a machine learning technique is proposed as a tool for selection of the best input combination for modeling process at non-deposition conditions of sediment *** one to seven dimensionless parameters,127 models are developed in the current *** order to evaluate the different parameter co mbinations and select the training and te sting data,four strategies are *** the densimetric Froude number(Fr) as the dependent parameter,a model with independent parameters of volumetric sediment concentration(CV) and relative particle size(d/R) gave the best results with a mean absolute relative error(MARE) of 0.1 and a root means square error(RMSE) of *** analysis is applied with a machine learning technique to investigate the credibility of the proposed *** percentage of the observed sample data bracketed by95% predicted uncertainty bound(95 PPU) is computed to assess the uncertainty of the best models.

关键词： Non-deposition Sediment transport Sensitivity analysis Sewer Uncertainty analysis Urban drainage

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Effects of the FIFA 11+program on performance,biomechanical measures,and physiological responses:A systematic review

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Journal of Sport and Health Science 2023年第2期12卷 226-235页

作者： Mojtaba asgari Bahareh Nazari Mario Bizzini Thomas Jaitner Institute for Sport and Sports Science TU Dortmund UniversityDortmund 44221Germany Faculty of Physical Education and Sports Science University of TehranKish Island branchKish Island 79416Iran Human Performance Lab Schulthess Clinic LengghaldeZürich 8008Switzerland

Background:The side effects of the FIFA 11+program on performance have not been generally *** objective of this study was to synthesize the literature on the effects of the 11+on players’***:Five online databases(PubMed,Scopus,ScienceDirect,Springer,and Google Scholar)were searched(from April 2006 to March 2022)using predefined keywords and *** potential references were primarily recorded through Endnote and imported to *** of the 123 references screened by 2 blinded researchers through the software,59 full texts were assessed for eligibility,33 of which were ultimately *** quality of the studies and the risk of bias were then *** ID,title,place,aim,design,start/end dates,population description,study criteria,statistical analysis,and outcomes were ***:Studies were conducted on male and female players aged 10-32 years *** quality of the studies was moderate to high,and except for unclear bias for blinding outcome assessment,the risk of bias for all domains was ***-term application of the 11+improved most biomechanical measures and physiological responses except for lower extremity stability,ankle evertors time latency,ankle dorsiflexion,and ***,the 11+showed acute negative effects on physical performance compared to dynamic warm-ups and non-significant effects on technical ***:Mid-to-long-term implementation of the 11+improved the maj ority of biomechanical and a couple of physical measure s but showed no effects on technical *** must be observed for using the 11+before competitions,as it could acutely decrease physical/technical *** the contradictory nature of the literature,further studies should evaluate the short-to-mid-term effects of the 11+.Further studies are required to address ankle responses to the 11+intervention.

关键词： Football Futsal Injury prevention Systematic review

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Seismic ground amplification induced by box-shaped tunnels

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Earthquake Engineering and Engineering Vibration 2022年第3期21卷 697-714页

作者： Damoon Feizi Jafar asgari Marnani Hamid Alielahi Mehdi Panji Department of Civil Engineering Faculty of Civil and Earth Resources EngineeringCentral Tehran BranchIslamic Azad UniversityTehranIran Department of Civil Engineering Zanjan BranchIslamic Azad UniversityZanjanIran

The growing use of underground structures,specifically to facilitate urban transportation,highlights the need to scrutinize the effects of such spaces on the seismic ground response as well as the surrounding *** this regard,the seismic ground amplification variations in the vicinity of single and twin box-shaped tunnels subjected to SV waves have been investigated by the finite difference *** evaluate the effects,generalizable dimensionless diagrams based on the results of parametric numerical analysis considering factors such as variations in the tunnels′depth,the distances between the tunnels,tunnel lining flexibility,and input wave frequency,have been *** addition,to assess the effects of underground box-shaped tunnels on the response spectrum of the ground surface,seven selected accelerograms have been matched based on a specific design spectrum for the stiff soil condition of Eurocode 8(CEN,2006).The results underline the significant amplification effect of the box-shaped tunnels on the ground motions,specifically in the case of horizontal twin tunnels,which should be given more attention in current seismic design practices for surface structures.

关键词： seismic amplification box-shaped tunnels response spectra numerical method parametric studies buried depth

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