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Chinese Journal of Chemistry 2011年第2期29卷 237-242页

作者： mahdi rezaei sameti Department of Physical Chemistry Faculty of Science Malayer University Malayer 65157 Iran

13C NMR chemical shifts have been calculated for structures of some substituted 3-anilino-2-nitrobenzo- [b]thiophenes （2o） and 2-anilino-3-nitrobenzo[b]thiophenes （3o） derivatives containing OH, NH2, OMe, Me, Et, H, F, Cl and Br. The molecular structures were fully optimized using B3LYP/6-31G（d,p）. The calculation of the 13C shielding tensors employed the GAUSSIAN 03 implementation of the gauge-including atomic orbital （GIAO） and continuous set of gauge transformations （CSGT） by using 6-311 ＋＋G（d,p） basis set at density functional levels of theories （DFT）. The isotropic and the anisotropy parameters of chemical shielding for all compounds are calculated. The predicted 13C chemical shifts are derived from equation δ=σ0＋σ where δ is the chemical shift, σ is the absolute shielding, and σ0 is the absolute shielding of the standard TMS. Excellent linear relationships have been observed between experimental and calculated 13C NMR chemical shifts for all derivatives.

关键词： DPT 13C NMR chemical shifts GIAO/CSGT

Using an Inhibitor to Prevent Plasticizer Migration from Polyurethane Matrix to EPDM Based Substrate

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Chinese Journal of Polymer Science 2019年第7期37卷 681-686页

作者： Hadi rezaei-Vahidian Tohid Farajpour mahdi Abdollahi Space Transportation Research Institute Iranian Space Research CenterTehranIran Polymer Reaction Engineering Department Faculty of Chemical EngineeringTarbiat Modares UniversityTehranIran

The loss of adhesion between the propellant and insulator is one of the most important problems in solid propellant motors due to migration of plasticizer to interface of propellant and insulator. In this work, the polyurethane (PU) binder containing DOP plasticizer was used as a polymeric matrix and β-cyclodextrin (β-CD) was applied as inhibitor agent to prevent plasticizer migration from the PU matrix into the ethylene propylene diene monomer (EPDM) substrate. To increase the compatibility of β-CD and PU matrix, a derivative of β-CD has been synthesized using toluene diisocyanate (β-CD-TDI). The synthesized derivative was characterized by MALDI-MS and FTIR-ATR analyses. FTIR-ATR results confirmed the formation of bonding between β-CD and the polymeric network while the MALDIMS results showed that the synthesized derivative contained two β-CD and 7 TDI molecules bonded to β-CD. Investigation of the mechanical properties of PU modified by β-CD-TDI showed a decrease in tensile strength and an increase in elongation at break with increasing β-CD-TDI content. DMTA results showed a decrement in crosslinking density by increasing the β-CD-TDI content. Also, to investigate plasticizer migration, extraction of the DOP plasticizer from samples was performed using dichloromethane solvent and its concentration was measured by gas chromatography. The results of migration evaluation after four months showed that using β-CD as an inhibitor agent in the PU binder could prevent the migration of plasticizer to EPDM substrate.

关键词： Plasticizer migration β-Cyclodextrin Polyurethane

An improved probabilistic load flow in distribution networks based on clustering and Point estimate methods

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Energy and AI 2023年第4期14卷 253-261页

作者： Morsal Salehi Mohammad mahdi rezaei Department of Electrical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIsfahanIran

Clustering approaches are one of the probabilistic load flow(PLF)methods in distribution networks that can be used to obtain output random variables,with much less computation burden and time than the Monte Carlo simulation(MCS)***,a challenge of the clustering methods is that the statistical characteristics of the output random variables are obtained with low *** paper presents a hybrid approach based on clustering and Point estimate *** the proposed approach,first,the sample points are clustered based on the𝑙-means method and the optimal agent of each cluster is ***,for each member of the population of agents,the deterministic load flow calculations are performed,and the output variables are ***,a Point estimate-based PLF is performed and the mean and the standard deviation of the output variables are ***,the statistical data of each output random variable are modified using the Point estimate *** use of the proposed method makes it possible to obtain the statistical properties of output random variables such as mean,standard deviation and probabilistic functions,with high accuracy and without significantly increasing the burden of *** order to confirm the consistency and efficiency of the proposed method,the 10-,33-,69-,85-,and 118-bus standard distribution networks have been simulated using coding in Python®programming *** simulation studies,the results of the proposed method have been compared with the results obtained from the clustering method as well as the MCS method,as a criterion.

关键词： Probabilistic load flow(PLF) Distribution network(DN) Monte Carlo simulation(MCS) k-means clustering(KMC) Point estimate method(PEM)

Propane-1,2,3-triyl tris(hydrogen sulfate): A mild and efficient recyclable catalyst for the synthesis of biscoumarin derivatives in water and solvent-free conditions

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Chinese Chemical Letters 2014年第1期25卷 183-186页

作者： Ramin rezaei Fatemeh Moezzi Mohammad mahdi Doroodmand Department of Chemistry Firoozabad BranchIslamic Azad University Department of Chemistry College of Sciences& Nanotechnology Research CenterShiraz University

A simple, efficient, and ecofriendly procedure has been developed using propane-l,2,3-triyl tris（hydrogen sulfate） as a catalyst for the synthesis of biscoumarin derivatives in water and solvent-free conditions. The significant features of the present protocol are simplicity, environmentally benign, high yields, no chromatographic separation, and recyclability of the catalyst.

关键词： Biscoumarin Aldehyde4-Hydroxycoumarin Propane-1 2 3-triyl tris(hydrogen sulfate)Homogeneous catalyst

Applying Surface-Based DNA Computing for Solving the Dominating Set Problem

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American Journal of Molecular Biology 2012年第3期2卷 286-290页

作者： Hassan Taghipour mahdi rezaei Heydar Ali Esmaili Department of pathology Tabriz University of medical sciences Tabriz Iran Department of Theoretical Physics and Astrophysics Tabriz University Tabriz 51664 Iran

The surface-based DNA computing is one of the methods of DNA computing which uses DNA strands immobilized on a solid surface. In this paper, we applied surface-based DNA computing for solving the dominating set problem. At first step, surface-based DNA solution space was constructed by using appropriate DNA strands. Then, by application of a DNA parallel algorithm, dominating set problem was resolved in polynomial time.

关键词： Parallel Computing Surface-Based DNA Computers Dominating Set Problem NP-Complete Problem

Solving the independent set problem by sticker based DNA computers

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American Journal of Molecular Biology 2012年第2期2卷 153-158页

作者： Hassan Taghipour Ahad Taghipour mahdi rezaei Heydar Ali Esmaili Department of Computer Engineering Faculty of Engineering Isfahan University Isfahan Iran Department of Pathology Tabriz University of Medical Sciences Tabriz Iran Department of Theoretical Physics and Astrophysics Tabriz University Tabriz Iran

In this paper, the sticker based DNA computing was used for solving the independent set problem. At first, solution space was constructed by using appropriate DNA memory complexes. We defined a new operation called “divide” and applied it in construction of solution space. Then, by application of a sticker based parallel algorithm using biological operations, independent set problem was resolved in polynomial time.

关键词： Parallel Computing Sticker Based DNA Computers Independent Set Problem NP-Complete Problem

Automatic Guidance of an Agricultural Tractor along with the Side Shift Control of the Attached Row Crop Cultivator

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Journal of Agricultural Science and Technology(B) 2012年第1期2卷 151-158页

作者： Javad Robati Hossein Navid mahdi rezaei Amir Rikhtehgar Ghiasi Faculty of Agricultural University of Tabriz Tabriz lran Faculty of Mechanical Engineering Sahand University of Technology Tabriz Iran Faculty of Computer and Electrical Engineering University of Tabriz Tabriz Iran

This paper presents the automatic guidance system of an agricultural tractor and the side shift control of the attached row crop cultivator using electro-hydraulic actuators. In order to simulate the dynamic behaviour of the tractor along with the attached cultivator, the modified bicycle model was adopted. Steering angle sensor, fibre optic gyroscope （FOG） and RTK-DGPS technologies are assumed for measurements of the steering angle, yaw rate and the lateral position of the tractor, respectively. The kinematics model was used for the implement. In this study four cascade controllers were designed and simulated for tractor guidance which consists ofPD, PD, P and PID controllers. Other PI and PID controllers also had been designed for implement side shifting purpose. Then, these two systems were combined and the performance of the whole system was evaluated through the simulation results. According to the results tractor reaches the desired path after less than 10 seconds. Simulations showed that the maximum deviation of the tractor from the desired path was about 5 cm within this period. And the cultivator blades would follow the predetermined path with steady state error of about 5 cm too.

关键词： Row crop cultivator yaw rate servo valve servo cylinder cascade controller.

An Empirical Study on Aflatoxin Occurrence in Nuts Consumed in Tehran, Iran 2013

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Health 2014年第8期6卷 649-653页

作者： Mohammad rezaei Fereshteh Karimi mahdi Parviz Ali Asghar Behzadi Morteza Javadzadeh Issa Mohammadpourfard Reza Ali Fallahzadeh Hasan Mohammadi Aghamirlou Ali Akbar Malekirad Department of Animal Science Faculty of Agriculture Saveh Branch Islamic Azad University Saveh Iran Department of Biology Faculty of Sciences Payam Noor University Tehran Iran Department of Environmental Health Engineering School of Public Health Yazd University of Medical Sciences Yazd Iran Department of Food Safety and Hygiene School of Public Health Tehran University of Medical Sciences Tehran Iran Department of Food Safety and Hygiene School of Public Health Yazd University of Medical Sciences Yazd Iran

By definition, “aflaxions” refer to a group of chemically toxic fungal metabolites, which are generated by specific species of genus Aspergillus. The species flourish on some of raw foods. This research is an attempt to assess aflatoxin contamination in nuts (Fig, Almond, Hazelnut, Walnut, Pistachio and Sunflower) available in Tehran city market in 2013. The assessments were done using ELISA method. To this end, 200 samples including Fig (n = 30), Almond (n = 25), Hazelnut (n = 25), Walnut (n = 40), Pistachio (n = 40), Sunflower (n = 40) were collected and analyzed regarding contamination with aflatoxin. The result of the tests was positive for 96.5% (193 samples) with total average concentration of 1.68 μg/kg (0 - 6 μg/kg). Moreover, in 6% (12 samples) of the cases, contamination exceeded the EU limits (4 μg/kg), while 100% of the samples met the legal limits of National Standard of Iran (15 μg/kg). In spite of contamination of majority of the cases, none was at hazardous level as the condition for growth of mycotoxin fungus or antioxidant activity in the nut was not suitable in Tehran (humidity level).

关键词： Aflatoxin ELISA Food Safety Food Toxicology Nuts

Road safety data collection systems in Iran: A comparison based on relevant organizations

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Chinese Journal of Traumatology 2020年第5期23卷 265-270页

作者： Homayoun Sadeghi-Bazargani Sakineh Sharifian Davoud Khorasani-Zavareh Raana Zakeri Mehdi Sadigh Mina Golestani Mousa Amiri Reza Masoudifar Farzad Rahmani Nasser Mikaeeli Javad Namvaran Khalil Pour-Ebrahim mahdi rezaei Babak Arabzadeh Bahram Samadirad Aliashraf Seyffarshad Fariba Mirza-Mohammadi-Teimorloue Shahin Kazemnezhad Soudabe Marin Saeede Sheikhi Reza Mohammadi Research Center for Evidence-Based Medicine Tabriz University of Medical SciencesTabrizIran Department of Health in Emergencies and Disasters School of Public Health and SafetyShahid Beheshti University of Medical SciencesTehranIran Workplace Health Promotion Research Center(WHPRC) Department of Health in Emergencies and DisastersShahid Beheshti University of Medical SciencesTehranIran Department of Health Services Management Iranian International Safe Community Support CenterTabriz University of Medical SciencesTabrizIran Road Traffic Injury Research Center Tabriz University of Medical SciencesTabrizIran Iranian Traffic Police TehranIran University of Tabriz Islamic Azad TabrizIran Department of Emergency Medicine Road Traffic Injury Research CenterTabriz University of Medical SciencesTabrizIran Iranian Traffic Police TabrizIran Payame Noor University(PNU) TehranIran Karafarin Insurance TabrizIran Legal Medicine Research Center Legal Medicine OrganizationTehranIran Shohada Medical Research and Training Hospital Tabriz University of Medical SciencesTabrizIran Department of Biostatistics and Epidemiology School of HealthTabriz University of Medical SciencesTabrizIran Department of Neurobiology Care Sciences and Society(NVS)H1Division of Family Medicine and Primary CareHuddingeSweden

Purpose:Various organizations and institutions are involved in road traffic injury(RTI)and crash registration such as police,forensic medicine organization,hospitals and emergency medical *** there is a substantial uncertainty in interpreting the data,duplicated data collection and missing data in relation to RTI in most *** study aims to identify data sources for RTI surveillance in Iran and to explore traffic safety data source domains,data elements and detailed information by each data ***:This is a qualitative study which was conducted in 2017 in *** were collected employing semi-structured interviews with informants in road safety organizations in relation to traffic safety including Police,Ministry of Health and Medical Education as well as Forensic Medicine Organization and other *** completing the preliminary extraction information,the minimum data set was used and compared in each ***:Eight different organizations relevant to road traffic safety were *** main domain of data provided by each one consists of Emergency Medical System form,Police KAM114 form,Ministry of Transport and Road Administration,Red Crescent Organization/Disaster Management Information System,Ministry of Health and Medical Education,Forensic Medicine Organization,Insurance Company and Ministry of *** system has its own database,based upon its scope and mainly at crash and postcrash status and little on pre-crash ***:All current registry systems are not surveillance systems for RTI *** data have been collected in various registry systems in Iran,but most of the collected variables are duplicated in each *** the other hand,some variables like alcohol and substance abuse,child seat belt,helmet use in relation to RTI prevention are missed in all ***,it is a critical need to integrate and establish a comprehensive surveillance system,with focus on the

关键词： Accidents,traffic Integrated surveillance system Prevention and control