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Numerical and Performance Analysis of one row Transonic Rotor with Sweep and Lean angle

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Journal of Thermal Science 2014年第5期23卷 438-445页

作者： Seyed Reza razavi Masoud Boroom Aerospace Engineering Department AmirKabir University of Technology

In this study,aerodynamic behaviors of swept and leaned blades were *** and tangential blade curvatures impacts on compressor's operating parameters were analyzed separately.A commercial CFD program which solves the Reynolds-averaged Navier-Stokes equations was used to find out the mentioned impact and the complicated flow field of transonic *** CFD method that was used for solving flow field's equation was validated by experimental data of NASA Rotor *** results showed that the compressor with curved rotors had higher efficiency,rotor pressure ratio and stable operating range compared to the compressor with un-curved *** curved rotors mostly had higher impact on the overall stable operating range compared to the other operating *** range involves choking point and stall point that were changed separately by using of bended *** finding the detailed impact of sweep and lean angle on transonic blades,various forms of lean and sweep angles were exerted to basic *** was found that sweep angles increased overall operating range up to 30%,efficiency up to 2%and pressure ratio up to 1%.Leaning the blades increased the safe operating range,the pressure ratio and efficiency by 14%,4%and 2%respectively.

关键词： compressor performance efficiency stable operational range surge improvement swept Rotor leaned rotor

2-Amino-4-(4-aminophenyl)thiazole application as an ionophore in the construction of a Lu(Ⅲ) selective membrane sensor

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Chinese Chemical Letters 2012年第3期23卷 343-346页

作者： Mohammad Reza Pourjavid Taherehsadat razavi NFCRS Nuclear Science&Technology Research InstituteAEOIP.O.Box 11365-8486TehranIran Instrumental Analysis Department Research Institute of Petroleum Industry(RIPI)P.O.Box 14665-137TehranIran

A derivative of thiazole（AAT） has been explored as a sensing material for preparation a selective Lu（III） PVC-based membrane *** proposed sensor exhibits a Nernstian response over a wide concentration range from 1.0×10^（-6） to 1.0×10^（-1） mol/L of Lu（Ⅲ） and the detection limit is 5.7×10^（-7） mol/*** sensor response is independent of pH of the solution in the range 3.2-8.8 and possesses the advantages of fast response time（～6） and in particular,good selectivity to the lutetium ions with regard to most common metal ions,and especially all lanthanide ions.

关键词： Membrane sensor Lu(Ⅲ) selective Thiazole derivative PVC Potentiometry

The Impact of the Covid-19 Pandemic on Iranian Oil and Gas Industry Planning:A Survey of Business Continuity Challenges

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International Journal of Disaster Risk Science 2022年第3期13卷 391-400页

作者： Seyyed Abdollah razavi Ali Asgary Marjan Khaleghi Department of Energy Economics and Management Tehran Faculty of PetroleumPetroleum University of Technology***TehranIran Disaster&Emergency Management School of Administrative StudiesFaculty of Liberal Arts&Professional StudiesYork UniversityTorontoONM3J 1P3Canada Department of Industrial Engineering Abadan Faculty of PetroleumPetroleum University of Technology***AbadanKhuzestanIran

The Covid-19 pandemic has severely affected various aspects of life,and its compounding and cascading impacts have been observed in most industries and *** oil and gas(O&G)industry was among the first to experience the impacts as the pandemic began due to the global economic recession and a sharp decline in demand for *** pandemic revealed major risk management and business continuity challenges and uncovered some of the vulnerabilities of the O&G industry and its major companies during a prolonged global *** and understanding how the Covid-19 pandemic impacted the O&G sector in different countries,considering their unique circumstances,can provide important lessons for managing the current and future similar *** study investigated various impacts of the Covid-19 pandemic on the O&G industry using Iran's Pars Oil and Gas Company(POGC)as a case *** were collected through indepth interviews with key managers of the *** methods,specifically thematic analysis,were used to analyze the *** of this study provide further insights into how the pandemic impacted the operations,risks,and business continuity of the *** results show that the pandemic caused significant operational,financial,and legal impacts by disrupting routine maintenance,reducing the availability of human resources under the public health measures and mobility restrictions,increasing processing and delivery times,increasing costs and decreasing revenues,and delaying contractual obligations.

关键词： Business continuity Covid-19 pandemic Global disaster Iran Oil and gas industry Pars Oil and Gas Company

Effects of turmeric(Curcuma longa)and its constituent(curcumin)on the metabolic syndrome:An updated review

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Journal of Integrative Medicine 2022年第3期20卷 193-203页

作者： Zeinab Vafaeipour Bibi Marjan razavi Hossein Hosseinzadeh Student Research Committee Mashhad University of Medical SciencesMashhad ***Iran Department of Pharmacodynamics and Toxicology School of PharmacyMashhad University of Medical SciencesMashhad ***Iran Targeted Drug Delivery Research Center Pharmaceutical Technology InstituteMashhad University of Medical SciencesMashhad ***Iran Pharmaceutical Research Center Pharmaceutical Technology InstituteMashhad University of Medical SciencesMashhad ***Iran

Metabolic syndrome(MS)involves people with the following risk factors:obesity,hypertension,high glucose level and *** can increase the risk of heart disease,stroke and type 2 diabetes *** prevalence of MS in the world’s adult population is about 20%–25%.Today,there is much care to use medicinal ***(Curcuma longa)as well as curcumin which is derived from the rhizome of the plant,has been shown beneficial effects on different components of ***,the purpose of this manuscript was to introduce different in vitro,in vivo and human studies regarding the effect of turmeric and its constituent on ***,different mechanisms of action by which this plant overcomes MS have been *** on studies,turmeric and its bioactive component,curcumin,due to their anti-inflammatory and antioxidant properties,have antidiabetic effects through increasing insulin release,antihyperlipidemic effects by increasing fatty acid uptake,anti-obesity effects by decreasing lipogenesis,and antihypertensive effects by increasing nitric *** to several in vivo,in vitro and human studies,it can be concluded that turmeric or curcumin has important values as a complementary therapy in ***,more clinical trials should be done to confirm these effects.

关键词： Turmeric Curcuma longa Curcumin Metabolic syndrome Diabetes Hyperlipidemia

A Distance Function for Computing on Finite Subsets of Euclidean Spaces

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 197-208页

作者： Hajar Ghahremani-Gol Farzad Didehvar Asadollah razavi Department of Mathematics Faculty of Science Shahed University Tehran *** Iran Department of Mathematics and Computer Science Amirkabir University of Technology 424 Hafez Av Tehran *** Iran Department Pure Mathematics Faculty of Mathematics and Computer Science Shahid Bahonar University of Kerman Kerman Iran

In practical purposes for some geometrical problems, specially the fields in common with computer science, we deal with information of some finite number of points. The problem often arises here is： “How are we able to define a plausible distance function on a finite three dimensional space？” In this paper, we define such a distance function in order to apply it to further purposes, e.g. in the field settings of transportation theory and geometry. More precisely, we present a new model for traveling salesman problem and vehicle routing problem for two dimensional manifolds in three dimensional Euclidean space, the second problem on which we focus on this line is, three dimensional triangulation.

关键词： geodesic least square method vehicle routing problem traveling salesman problem three dimensional triangulation

Weldability and liquation cracking behavior of ZhS6U superalloy during electron-beam welding

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 251-259页

作者： Arash Khakzadshahandashti Mohammad Reza Rahimipour Kourosh Shirvani Mansour razavi Department of Ceramic Materials and Energy Research Center Department of Material and Renewal Energy Iranian Research Organization for Science and Technology (IROST)

The weldability of the ZhS6U nickel-based superalloy, which is prone to solidification cracking during electron-beam welding(EBW) repair processes, was investigated. The effects of two different pre-weld heat-treatment cycles on the final microstructure before and after welding were examined. Welds were made on flat coupons using an EBW machine, and the two heat-treatment cycles were designed to reduce γ′ liquation before welding. Microstructural features were also examined by optical and scanning electron microscopy. The results showed that the change in the morphology and size of the γ′ precipitates in the pre-weld heat-treatment cycles changed the ability of the superalloy to release the tensile stresses caused by the matrix phase cooling after EBW. The high hardness in the welded coupons subjected to the first heat-treatment cycle resulted in greater resistance to stress release by the base alloy, and the concentration of stress in the base metal caused liquation cracks in the heat-affected zone and solidification cracks in the weld area.

关键词： weldability ZhS6U superalloy electron beam welding heat-affected zone liquation cracking pre-weld heat treatment

Ethylene-Propene Copolymerization with C1-symmetric ansa-Fluorenyl-zirconocene Catalysts: Effects of Catalyst Structure and Comonomer on Molar Mass

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Chinese Journal of Polymer Science 2020年第3期38卷 220-230,I0005页

作者： Simona Losio Laura Boggioni Massimiliano Cornelio Abbas razavi Incoronata Tritto CNR–Istituto di Scienze e Tecnologie Chimiche"G.Natta"(CNR-SCITEC) via Alfonso Corti 12-20133 MilanoItaly Total Petrochemicals Research Zone Industrielle CB-7181 FeluyBelgium

Ethylene-propene copolymers have been synthesized by three C1-symmetric metallocene molecules(1,2,and 3),having tert-butyl substituents on the Cp moiety,on the fluorenyl moiety,or on both moieties,and methylaluminoxane(MAO)at different polymerization temperatures and monomer *** were investigated by 13 C-NMR,1 H-NMR,and SEC analyses.A relationship was found between[EEE]/[E]ratios and copolymer molar masses in each series:the higher the[EEE]/[E]ratio,the lower the copolymer molar *** parity of[EEE]/[E]ratio,copolymer molar mass follows the order 1>>3>*** end group analysis reveals that copolymers mainly terminate when propene is the last inserted unit,confirming that it is the greater facility of Mt-P-E-poly(E-co-P)to terminate that influences the copolymer molar *** the catalysts considered,catalyst 1,which gives syndiospecific polypropene,gives greater activities,comonomer incorporation,and molar *** 3,which gives isospecific polypropene,in copolymerization performs better than 2,having the same bridge,with respect to activities,ethylene content,and molar *** good performance of this catalyst arises from the not necessity of polymer chain to back skip when ethylene is the last inserted unit.

关键词： Ethylene-propene Metallocene catalysts Copolymers Microstructure Molar masses

Experimental investigation of the application of Eucalyptus bark to prevent lost circulation in pay zones with acid dissolution capability

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Petroleum 2021年第2期7卷 152-159页

作者： Mostafa Sedaghatzadeh Khalil Shahbazi Peyman Pourafshary Seyed Ali razavi National Iranian Drilling Company Ahvaz90161635Iran Petroleum University of Technology Abadan***Iran School of Mining and Geoscience Nazarbayev UniversityNur-Sultan010000Kazakhstan

Loss of drilling fluid is a common problem during the drilling of wells and it restricts the appropriate functionality of *** fluid loss significantly increases drilling costs and non-productive time as well as the drilling operation *** investigations have been carried out in order to find appropriate mud additives that either block fractures and pores or reduce fluid loss by improving the fluid ***,environmentally friendly and effective additives are still required by the drilling ***,the application of available materials in each region,to produce appropriate additives,is a challenge for the oil *** this study,Eucalyptus Camaldulensis(EUC)bark powder has been chosen as a new,fibrous,cheap,environmentally friendly and available material to control fluid loss,particularly in southern *** characterization tests,such as acid dissolution and fluid loss control,were carried out to study the performance of the new proposed *** by hydrochloric acid and sulfuric acid were studied at various acid concentrations and *** fluid loss was also measured at different EUC *** study showed that EUC powder can reduce the final fluid loss by 88-97%,the initial fluid loss by 45-66%,and the total loss by 87e94%,which is a satisfactory level.

关键词： Eucalyptus bark Lost circulation Acid solubility Drilling mud Fluid loss

DPP-4 inhibitors and GLP-1RAs:cardiovascular safety and benefits

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Military Medical Research 2023年第2期10卷 227-241页

作者： Michael razavi Ying-Ying Wei Xiao-Quan Rao Ji-Xin Zhong Tulane University School of Medicine New OrleansLA 70112USA Department of Rheumatology and Immunology Tongji HospitalTongji Medical College of Huazhong University of Science and Technology1095 Jiefang AveWuhan 430032China Department of Cardiovascular Medicine Tongji HospitalTongji Medical College of Huazhong University of Science and Technology1095 Jiefang AveWuhan 430032China Institute of Allergy and Clinical Immunology Tongji HospitalTongji Medical College of Huazhong University of Science and TechnologyWuhan 430032China

Glucagon-like peptide-1 receptor agonists(GLP-1RAs)and dipeptidyl peptidase-4 inhibitors are commonly used treatments for patients with type 2 diabetes mellitus(T2DM).Both anti-diabetic treatments function by playing key modulatory roles in the incretin *** these drugs have been deemed effective in treating T2DM,the Food and Drug Administration(FDA)and some members of the scientific community have questioned the safety of these therapeutics relative to important cardiovascular *** a result,since 2008,the FDA has required all new drugs for glycemic control in T2DM patients to demonstrate cardiovascular *** present review article strives to assess the safety and benefits of incretin-based therapy,a new class of antidiabetic drug,on the health of patient cardiovascular *** the process,this review will also provide a physiological overview of the incretin system and how key components function in T2DM.

关键词： Glucagon-like peptide-1 receptor agonists Dipeptidyl peptidase-4 inhibitors Type 2 diabetes mellitus Cardiovascular outcome