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Esterification of Carboxylic Acids and Diacids by Trialkyl Borate under Solvent- and Catalyst-Free Conditions

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Chinese Journal of Chemistry 2007年第12期25卷 1878-1882页

作者： mANSOORI, Yagoub TATAROGLU SEYIDOV, Firdovsi BOHLOOLI, Shahrbanoo ZAmANLOO, mohammad Reza ImANZADEH, gholam Hassan Department of Applied Chemistry College of Science The University ofMohaghegh Ardabili Ardabil Iran 56199-11367 Chemistry Department Azad Islamic University of Tabriz Darvaze Tehran Tabriz-lran

Esterification or transesterification reactions are usually carried out in the presence of homogeneous or heterogeneous catalysts. However, recently a new method was reported for the esterification of carboxylic acids by tributyl borate under solvent- and catalyst-free conditions. In order to show the synthetic ability of trialkyl borate esters in the esterification reactions, here, the esterification of other carboxylic acids and diacids by tributyl-, triisoamyl-, and tribenzyl borate under the same conditions were reported. Some of the prepared ester and diester products have found wide applications as plasticizers and synthetic ester base lubricants. The esterification reactions have been cleanly carried out in the absence of any solvent under catalyst-free conditions. The maximum rate belongs to isoamyl trichloroacetate （VIb） which reached about 76% within about 6.5 h. On the basis of obtained findings, it seems that electron withdrawing groups on carboxylic acid facilitate the esterification reaction.

关键词： esterification borate ester solvent-flee

A mild and efficient method for the methoxymethylation and acetylation of alcohols promoted by benzyltriphenylphosphonium tribromide

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Chinese Chemical Letters 2010年第10期21卷 1187-1190页

作者： Farhad Shirini gholam Hossein Imanzadeh Seyyed Ali Reza mousazadeh Iraj mohammadpoor-Baltork masoumeh Abedin Department of Chemistry College of ScienceUniversity of Guilan Department of Chemistry College of ScienceUniversity of Mohaghegh-Ardabili Department of Chemistry College of ScienceIsfahan University

A mild and efficient method for the conversion of alcohols to their corresponding methoxymethyl ethers and acetates using benzyltriphenylphosphonium tribromide （BTPTB） as catalyst is described. All reactions were pe... 详细信息

关键词： Benzyltriphenylphosphonium tribromide Alcohols methoxymethylation Acetylation Heterogeneous reaction conditions

Effect of testosterone replacement on feeding behaviors after acute and chronic stress in gonadectomized male NmRI mice

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Frontiers in Biology 2017年第6期12卷 430-441页

作者： Sara Salehi Shemiran gholam Hossein meftahi q Hedayat Sahraei Negin Ghobadi Department of Biology School of Biological Sciences Islamic Azad University North Tehran Branch Tehran Iran Neuroscience Research Centez Baqiyatallah University of medical Sciences Tehran Iran

Background We study the role of gonadectomy on the response to unavoidable stress and the role of testosterone replacement on gonadectomy in the male Naval medical Research Institute mice (30±5 g) were studied. For this purpose, the hormonal and metabolic changes were *** In the experimental group, the gonads were surgically removed, and a cannula was inserted into the left lateral ventricle. For acute and chronic stress induction, animals were placed in the communication box for 30 min for one day and four consecutive days, respectively. The animals received different doses of intraventricular (ICV) testosterone (0.01, 0.05, 0.1 μg/mouse) 5 minutes or intraperitoneal (IP) testosterone (0.05, 0.01, 0.1 mg/kg) 30 minutes before the stress *** The results showed that acute and chronic stress increases plasma cortisol concentration. IP testosterone injections of testosterone did not decrease cortisol concentrations in response to acute stress, whereas ICV injections did reduce cortisol concentrations. The stress reduced anorexia time, while the administration of testosterone increased anorexia time. In addition, acute stress reduced food intake in the gonadectomized mice. IP testosterone at 0.01 and 0.05 mg/kg increased food intake. Additionally, stress in gonadectomized mice reduced water intake, while the IP injection of testosterone in chronic stress further reduced water intake. Also, stress reduced the animals’ brain/adrenal volumes, while the IP and ICVinjection of testosterone at 0.01 mg/kg inhibited this *** The results showed that the IP (0.05, 0.01, 0.1 mg/kg) and ICV (0.01, 0.05, 0.1 μg/mouse) administration of testosterone in the gonadectomized mice can modulate hormonal and metabolic changes induced by stress.

关键词： anorexia cortisol food intake gonadectomy water intake

Semi-Self-Supervised Learning for Semantic Segmentation in Images with Dense Patterns

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Plant Phenomics 2023年第2期5卷 149-163页

作者： Keyhan Najafian Alireza Ghanbari mahdi Sabet Kish mark Eramian gholam Hassan Shirdel Ian Stavness Lingling Jin Farhad maleki Department of Computer Science University of SaskatchewanSaskatoonSaskatchewanCanada mathematics Department Faculty of SciencesUniversity of QomQomIran Department of mathematics Faculty of Mathematical ScienceShahid Beheshti UniversityTehranIran Department of Computer Science University of CalgaryCalgaryAlbertaCanada

Deep learning has shown potential in domains with large-scale annotated ***,manual annotation is expensive,time-consuming,and ***-level annotations are particularly costly for semantic segmentation in images with dense irregular patterns of object instances,such as in plant *** this work,we propose a method for developing high-performing deep learning models for semantic segmentation of such images utilizing little manual *** a use case,we focus on wheat head *** synthesize a computationally annotated dataset—using a few annotated images,a short unannotated video clip of a wheat field,and several video clips with no wheat—to train a customized U-Net *** the distribution shift between the synthesized and real images,we apply three domain adaptation steps to gradually bridge the domain *** using two annotated images,we achieved a Dice score of 0.89 on the internal test *** further evaluated on a diverse external dataset collected from 18 different domains across five countries,this model achieved a Dice score of *** expose the model to images from different growth stages and environmental conditions,we incorporated two annotated images from each of the 18 domains to further fine-tune the *** increased the Dice score to *** result highlights the utility of the proposed approach in the absence of large-annotated *** our use case is wheat head segmentation,the proposed approach can be extended to other segmentation tasks with similar characteristics of irregularly repeating patterns of object instances.

关键词： instance utilizing consuming

Predicting maximum Lifespan Limits at mean menopausal Age

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Journal of mathematical Research with Applications 2025年第1期 133-142页

作者： m.SUmATHI S.ANTONY CARLA Department of mathematics N.M.S.S.Vellaichamy Nadar College Research Scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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GIS-based spatial analysis of urban traffic accidents： Case study in mashhad, Iran

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第3期4卷 290-299页

作者： gholam Ali Shafabakhsh Afshin Famili mohammad Sadegh Bahadori Department of Civil Engineering Semnan University Semnan Iran Glenn Department of Civil Engineering Clemson Unioersity Clemson SC 29634 USA Instituto Superior Tecnico University of Lisbon Lisbon 1600-276 Portugal

There is a growing concern in traffic accident rate in recent years. Using mashhad city （Iran second populous city） traffic accident records as case study, this paper applied the combi- nation of geo-information technology and spatial-statistical analysis to bring out the influence of spatial factors in their formation. The aim of the study is to examine 4 clustering analyses to have a better understanding of traffic accidents patterns in complex urban network. In order to deploy the clustering technique in urban roads, 9331 point features for inner city traffic accidents during 12 months have been registered according to their x and y location in geographic information system （GIS）. The mentioned areas were analyzed by kernel density estimation （KDE） using ARCmAP and two other analyses using SANET 4th edition software so that the results of network analysis can be compared with traditional KDE method. In addi- tion, this research introduces five classifications for determining the eventfulness of the under study area based on standard deviation and to make priority in creating security in the area. The nearest neighbor and K-function output analysis consist of four curves and regarding the fact that for all fatal, injury and property damage only crashes, the observed value curve is above the 5% confidence interval. Accidents in the study region are more clustered than ex- pected by random chance. The importance of this study is to use GIS as a management system for accident analysis by combination of spatial-statistical methods.

关键词： Traffic accidents Hotspots Kernel density analysis Nearest neighbor K-function

Kinetics analysis of non-isothermal decomposition of Ag_2O-graphite mixture

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Transactions of Nonferrous metals Society of China 2014年第9期24卷 2991-3000页

作者： Seyed Hadi SHAHCHERAGHI gholam Reza KHAYATI Department of mineral Processing Engineering Shahid Bahonar University of KermanKerman Iran Department of materials Science and Engineering Shahid Bahonar University of KermanKerman Iran

The thermal decomposition kinetics of Ag2O-graphite mixture was systematically studied using a differential scanning calorimeter（DSC） in terms of model-fitting malek approach, integral master plot method and model-free advanced isoconversional method of Vyazovkin. The results showed that the thermal decomposition occurred in two stages. The first step was the decomposition process of Ag2 O to form porous silver particles as a complex process with the participation of at least two mechanisms, and the second step corresponded to the structural change from porous particles to silver bulk crystals as a single-step process.

关键词： Ag2O advanced isoconversional method kinetic modeling Sestak–Berggren model

Practical application of failure criteria in determining safe mud weight windows in drilling operations

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Journal of Rock mechanics and Geotechnical Engineering 2014年第1期6卷 13-25页

作者： R.gholam A.moradzadeh V.Rasoul J.Hanach Department of mining Petroleum and Geophysics Shahrood University of Technology Departmentof Petroleum Engineering Curtin University Geological Division Iranian Offshore Oilfield Company

Wellbore instability is reported frequently as one of the most significant incidents during drilling *** of wellbore instability includes estimation of formation mechanical properties and the state of in situ *** this analysis,the only controllable parameter during drilling operation is the mud *** the mud weight is larger than anticipated,the mud will invade into the formation,causing tensile failure of the *** the other hand,a lower mud weight can result in shear failures of rock,which is known as borehole *** predict the potential for failures around the wellbore during drilling,one should use a failure criterion to compare the rock strength against induced tangential stresses around the wellbore at a given mud *** mohr–Coulomb failure criterion is one of the commonly accepted criteria for estimation of rock strength at a given state of ***,the use of other criteria has been debated in the *** this paper,mohr–Coulomb,Hoek–Brown and mogi–Coulomb failure criteria were used to estimate the potential rock failure around a wellbore located in an onshorefield of *** log based analysis was used to estimate rock mechanical properties of formations and state of *** results indicated that amongst different failure criteria,the mohr–Coulomb criterion underestimates the highest mud pressure required to avoid breakouts around the *** also predicts a lower fracture gradient *** addition,it was found that the results obtained from mogi–Coulomb criterion yield a better comparison with breakouts observed from the caliper logs than that of Hoek–Brown *** was concluded that the mogi–Coulomb criterion is a better failure criterion as it considers the effect of the intermediate principal stress component in the failure analysis.

关键词： mud weight windows Failure criterion Breakout Fracturing Intermediate principal stress

The role of dopamine D2 receptors in the amygdala in metabolic and behavioral responses to stress in male Swiss-Webster mice

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Frontiers in Biology 2017年第4期12卷 298-310页

作者： maryam Hassantash Hedayat Sahraei Zahra Bahari gholam Hossein meflahi Roshanak Vesali Faculty of Psychology & Education University ofTehran Tehran Iran Neuroscience Research Center Baqiyatallah University of Medical Sciences Tehran Iran Department of Physiology and Biophysics Faculty of Medicine Baqiyatallah University of Medical Sciences Tehran Iran

OBJECTIVE： The D2 dopamine receptor is found in different parts of the amygdala. However, its contribution to stress is unknown. Thus, in the present study, we examined the effects of excitation and inhibition of D2 dopamine receptors in the amygdala on the metabolic and hormonal changes in response to stress. mETHODS： Bilateral amygdala cannulation was carried out in Swiss-Webster mice （n = 7）. On recovery, different doses of the dopamine D2 receptor antagonist, sulpiride （1, 5 and 10μg/mouse） or the dopamine D2 receptor agonist, bromocriptine （1, 5 and 10μg/mouse） were injected into the amygdala. The animals were then placed in stress apparatus （communication box） where they received an electric shock （10 mV voltage, 10 Hz frequency and 60 s duration） after 30 rain. The animal＇s activities were recorded for 10 min before and 10 min after the stress induction. Locomotion, rearing and freezing were investigated. metabolic changes, such as food and water intake and anorexia, were studied. RESULTS： The results show that stress increased the concentration of plasma corticosterone, which was followed by a decrease in locomotion and rearing and an increase in freezing behavior. Furthermore, both weight and water and food intake were reduced. Administration of bromocriptine led to a reduction of corticosterone at doses of 1 and 5 ~tg/mouse and an increase of corticosterone at 10 ~tg/mouse. Additionally, lower doses ofbromocriptine （1 and 5 ~tg/mouse） caused an increase in locomotion and rearing and a decrease in freezing behavior. Similar results were observed with sulpiride injection. CONCLUSION： D2 dopamine receptors can play a major role in the amygdala in stress. Both an agonist and an antagonist of the D2 receptor attenuate the metabolic and hormonal changes observed in response to stress

关键词： amygdala anorexia bromocriptine corticosterone D2 dopamine recepetor sulpiride