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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 658-666页

作者： ahmad zare S.R.Hosseini Department of Materials Engineering Maleke-ashtar University of Technology

The influence of soaking time in deep cryogenic treatment on the tensile and impact properties of low-alloy medium-carbon HY-TUF steel was investigated in this study. Microstructural studies based on phase distribution mapping by electron backscatter diffraction show that the deep cryogenic process causes a decrease in the content of retained austenite and an increase in the volume fraction of η-carbide with increasing soaking time up to 48 h. The decrease in the content of retained austenite from ~1.23vol% to 0.48vol% suggests an isothermal martensitic transformation at 77 K. The η-type precipitates formed in deep cryogenic-treated martensite over 48 h have the Hirotsu and Nagakura orientation relation with the martensitic matrix. Furthermore, a high coherency between η-carbide and the martensitic matrix is observed by high-resolution transmission electron microscopy. The variations in macrohardness, yield strength, ultimate tensile strength, and ductility with soaking time in the deep cryogenic process show a peak/plateau trend.

关键词： low alloy steel medium carbon steel cryogenic treatment microstructure mechanical properties fractography

原位生成的Ph_3C^+均相有机催化剂催化4,4'-芳亚甲基-二(3-甲基-1-苯基-1H-吡唑-5-醇)高效合成（英文）

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催化学报 2014年第1期35卷 85-89页

作者： Abdolkarim zare Maria Merajoddin ahmad Reza Moosavi‐zare Mahmoud zarei Department of Chemistry Payame Noor University Department of Chemistry University of Sayyed Jamaleddin Asadabadi Faculty of Chemistry Bu‐Ali Sina University

Trityl chloride(Ph3CCl) efficiently catalyzes the condensation of 3‐methyl‐1‐phenyl‐1H‐pyrazol‐ 5(4H)‐one and aromatic aldehydes under mild and solvent‐free conditions, affording 4,4'‐(arylmethylene)‐ bis(3‐methyl‐1‐phenyl‐1H‐ pyrazol‐5‐ol)s in high to excellent yields and in short reaction time. The presence of the requisite organocatalytic trityl carbocation(Ph3C+) species was confirmed by analysis of infrared, 1H NMR, and ultra violet spectral data. A plausible mechanism was proposed for the reaction based on the observations and literature precedent.

关键词：有机催化剂三苯甲基碳正离子亚甲基有效合成原位生成苯基芳基

乙酸功能化离子液体作为高效、可回收的催化剂用于2-萘酚与芳醛缩合反应(英文)

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催化学报 2014年第4期35卷 573-578页

作者： ahmad Reza Moosavi-zare Mohammad Ali Zolfigol Omid Khaledian Vahid Khakyzadeh Department of Chemistry University of Sayyed Jamaleddin Asadabadi Asadabad *** Iran Faculty of Chemistry Bu Ali Sina University Hamedan *** Iran

An efficient solvent‐free protocol for the synthesis of 14‐aryl‐14H‐dibenzo[a,j]xanthenes from the condensation of 2‐naphthol with arylaldehydes, using acetic acid functionalized imidazolium salts (1‐carboxymethyl‐3‐methylimidazolium bromide ([cmmim]Br) and 1‐carboxymethy1‐3-me-thylimidazolium tetrafluoroborate([cmmim]BF4) as reusable catalysts, has been developed. The turn over frequency on the catalysts is several times higher than the other previously reported catalysts. Also, thermal gravimetric analysis and powder X‐ray diffraction pattern of the catalysts have been studied.

关键词：可重复使用催化剂离子液体萘酚缩合芳醛功能化醋酸

新型磺酸功能化吡啶盐酸盐离子液体催化剂用于六氢喹啉合成(英文)

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催化学报 2013年第10期34卷 1936-1944页

作者： Ardeshir Khazaei Mohammad Ali Zolfigol ahmad Reza Moosavi-zare Javad Afsar Abdolkarim zare Vahid Khakyzadeh Mohammad Hassan Beyzavi Faculty of Chemistry Bu-Ali Sina University Department of Chemistry University of Sayyed Jamaleddin Asadabadi Department of Chemistry Payame Noor University Institut für Chemie und Biochemie Freie Universitt Berlin

Sulfonic acid functionalized pyridinium chloride [pyridine-SO3 H]Cl has been synthesized as a novel Brnsted acidic ionic liquid and characterized on the basis of its FT-IR,1H and 13C NMR,MS,ther-mogravimetry,and derivative thermogravimetry *** material has also been used as a highly efficient,homogeneous,and reusable catalyst for the preparation of hexahydroquinolines according to the one-pot multi-component condensation of arylaldehydes,dimedone(5,5-dimethylcyclohexane-1,3-dione),β-ketoesters,and ammonium acetate under solvent-free conditions.

关键词： Brnsted acidicionic liquid Sulfonic acid functionalized pyridinium chloride [Pyridine-SO3 H]Cl Hexahydroquinoline Solvent-free synthesis

Cervical dilation and improvement of reproductive performance in fat-tailed ewes via cervical dilator treatments

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Asian pacific Journal of Reproduction 2017年第2期6卷 93-96页

作者： Reza Masoudi ahmad zare Shahneh Armin Towhidi Hamid Kohram Abbas Akbarisharif Mohsen Sharafi Mahdi Zhandi MAMM Shahab-El-Deen Department of Animal Science University College of Agriculture and Natural ResourcesUniversity of TehranKarajIran The Breeding Station of Zandi Sheep PishwaVaraminIran Department of Poultry Science Faculty of AgricultureUniversity of Tarbiat Modares.TehranIran Department of Animal Production Faculty of AgricultureSuez Canal UniversityIsmailiaEgyp

Objective:To determine the effect of different cervical dilators on cervical dilation and reproductive performance of fat-tailed ***: In experiment 1140 ewes were divided into seven groups with seven different treatments as following: 10 mL normal saline (control group), 100 IU oxytocin (OT group), 100 μg estradiol and 100 IU oxytocin (E2+OT group), 5 mL relaxin (R group), 2 mL sensiblex (SEN group), 200 μg misoprostol (MIS group) or 200 μg dinoprostone (DIN group). In experiment 2, artificial insemination was applied for evaluation of reproductive performance in experimental ***: In experiment 1, the highest cervical dilation was observed in OT (90%) and E2+OT (100%) groups (P<0.05), while no significant differences was found among DIN, MIS, SEN and R groups (80%, 75%, 70% and 65%, respectively). In addition, the lowest cervical dilation was observed in control group. Experiment 2 found no significant differences among control, OT and E2+OT groups. The highest pregnancy rate, parturition rate and lambing rate were observed in OT groups (60%, 60% and 70%, respectively) and E2+OT groups (65%, 60% and 70%, respectively) compared to SEN, R, MIS and DIN groups (P<0.05).Conclusions:Oxytocin treatment alone or with estradiol could be used as a suitable dilator for improving reproductive efficiency during artificial insemination in fat-tailed ewes.

关键词： Artificial insemination Cervical dilators Fat-tailed ewes Reproductive performance

Road and Tunnel Extraction from SPOT Satellite Images Using Neural Networks

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Journal of Geographic Information System 2013年第1期5卷 69-74页

作者： Nima Ghasemloo Mohammad Reza Mobasheri ahmad Madanchi zare Mehran Memar Eftekhari Khaje Nasireddin Toosi University of Technology Tehran Iran Researcher of Malek Ashtar University of Technology Tehran Iran

Road extraction from the satellite images can be used in producing road maps as well as managing and developing geospatial databases. In this work, the extraction of roads from SPOT satellite images using artificial neural network has been studied. Then the location of tunnel is extracted from image using digital elevation information. Also it is tried to enhance the precision of the road extraction method using spectral information as well as texture and morphology. The method was implemented on SPOT satellite images of Tabrizand Miyaneh (Iran). The results of this research indicate that it would be possible to promote the precision of road extraction by using texture and morphology in image classifycation using neural networks. Finally the location of tunnel was extracted by digital elevation information. Junctions of roads and mountains have high potential in locating the tunnel. For this reason, in this study, the junctions of roads and mountains were also detected and used.

关键词： Neural Networks Road Classification Texture

The Acoustic Performance of 3D Printed Multiple Jet Nozzles with DifferentConfigurations

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Sound & Vibration 2020年第1期54卷 43-55页

作者： Ali Safari Variani Ali Dastamoz Sajad zare ahmad Nikpey Saeid ahmadi Department of Occupational Health and Safety School of Public HealthQazvin University of Medical SciencesQazvinIran Department of Occupational Health and Safety School of Public HealthKerman University of Medical SciencesKermanIran

This work investigated multiple jet nozzles with various geometrical shape,number of exits,and material on reducing noise radiated from jet *** are categorized in two groups with few and many exit numbers,each with various exit shapes,slot and circular,and ***,nozzles are designed and then fabricated by a 3D printer,Form Labs,Form2USA,with polymeric ***,the nozzle with the most noise reduction made of stainless *** and air thrust were measured at three air pressure gauges,3,5,7 BAR and directions from nozzle apex,30°,90°,135°.Nozzles with slot exit shape made of both plastic and stainless steel revealed the most noise reduction among all nozzles with few exit numbers,nearly 11–14 dB(A)and 11.5–15 dB(A),*** average,slotted nozzle noise reduction was nearly 5–6 dB(A)more than finned ***,nozzles with more exit numbers,finned and finned-central exit,illustrated much more noise reduction than nozzles with few exit numbers,by almost 16–18 dB(A),they represented similar *** tested nozzles and open pipe demonstrated equal air thrust at each pressure *** nozzles with slotted exit shape,either plastic or stainless steel,can provide reasonable noise reduction in comparison to other configuration with few exit *** contrast,nozzles with more exit numbers demonstrated the most noise reduction.

关键词： Jet noise multiple jet nozzle noise reduction 3D design exit shape nozzle geometry

Prediction of overbreak depth in Ghalaje road tunnel using strength factor

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International Journal of Mining Science and Technology 2018年第4期28卷 671-676页

作者： Ako Daraei Shokrollah zare Civil Engineering Department Soran University School of Mining Petroleum & Geophysics Engineering Shahrood University of Technology

It is well known that the overbreak caused by the blasting damage during tunnel excavation increases costs associated with filling the collapsed area with shotcrete and results in filing of a claim by the contractor. This paper outlines a new approach for prediction the overbreak depth during tunnel construction. Hence, firstly excavation damage zone(EDZ) are determined by average specific charge in each zone. Numerical modelling is used to simulate the EDZ around tunnel boundary and the overbreak depth are calculated by the rock strength factor. The predicted overbreak depth compared with observed field data from a case study. The results show that there exists an approximately up to 40% difference between the prediction and the observed volume of overbreak depth. Therefore, the method can be well used to predict the overbreak depth to estimate more precision of shotcrete and concrete volumes in tunnelling cost during design phase.

关键词： Overbreak Blasting Excavation damaged zone Strength factor Tunneling

Prevalence and risk factors of gastroesophageal reflux disease in Qashqai migrating nomads, southern Iran

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World Journal of Gastroenterology 2009年第8期15卷 961-965页

作者： ahmad Mostaghni Davood Mehrabani Farnaz Khademolhosseini Seyed Jalil Masoumi Fariba Moradi Najaf zare Mehdi Saberi-Firoozi Gastroenterohepatology Research Center Nemazee Hospital Shiraz University of Medical Sciences Shiraz Iran Office of Vice Chancellor for Health Affairs Shiraz University of Medical Sciences Shiraz Iran Department of Biostatistics School of Medicine Shiraz University of Medical Sciences Shiraz Iran

AIM： To investigate the prevalence and risk factors of gastroesophageal reflux disease （GERD） symptoms in Qashqai migrating nomads with a different life style in Fars province, southern Iran. METHODS： In summer 2006, 748 Qashqai migrating nomads aged 25 years or more were enrolled using a multiple-stage stratified cluster random sampling method. A questionnaire consisting of demographic characteristics, lifestyle and GERD symptoms （heartburn, regurgitation, chest pain, dysphagia, hoarseness and cough） as completed for each subject. RESULTS： The questionnaire was completed in 717 subjects. The prevalence rate of GERD, defined as reflux occurring at least one time per week in the preceding year, was 33% （237 subjects）. The prevalence was higher in older individuals （36.0% vs 28.9%, P 〈 0.05） and in those with other gastrointestinal complaints （51.0% vs 27.8%, P 〈 0.001）, but not different in obese and non-obese subjects. It was also higher in those consuming fruits and vegetables more than once a week （36.2% vs 17.3%, P 〈 0.001）. GERD had a positive correlation with smoking （42.1% vs 27.8%, P 〈 0.001）, but a negative relation with non-alcoholic beverages. The association between GERD and non-steroidal antiinflammatory drugs （NSAIDs） consumption was also significant （40.2% vs 25.4%, P 〈 0.001）. CONCLUSION： The prevalence of GERD （33%） is very high in Qashqai migrating nomads which may be due to a lower socioeconomic and educational level of these people and difference in the life style. Older age, frequent consumption of fruits and vegetables, smoking and NSAIDs are risk factors for GERD in this population.

关键词： Gastroesophageal reflux disease Prevalence Risk factors Nomads Iran

Multicomponent synthesis of dihydropyridines catalyzed by L-proline

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Chinese Chemical Letters 2011年第5期22卷 531-534页

作者： Leila zare Mohammad Nikpassand Department of Organic Chemistry Islamic Azad University-Rasht BranchRashtIran

Multicomponent synthesis of mono and bis 4-substituted-1,4-dihydropyridines from aldehydes,dimedone and ammonium acetate in the presence of an efficient recyclable catalyst,L-proline,in high yield and short reaction t... 详细信息

关键词： Multicomponent Dihydropyridines Dimedone L-Proline