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A novel and efficient strategy for the synthesis of various carbamates using carbamoyl chlorides under solvent-free and grinding conditions using microwave irradiation

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Chinese Chemical Letters 2012年第8期23卷 883-886页

作者： Hassan Zare mohammad mehdi ghanbari Marzieh Jamali Abdollah Aboodi Department of Chemistry Firoozabad BranchIslamic Azad UniversityFiroozabadIran Department of Chemistry Sarvestan BranchIslamic Azad UniversitySarvestanIran

We present an efficient, fast and simple strategy of generating the intermediate carbamoyl chlorides from secondary amines using stoichiometric amounts of bis（trichloromethyl）carbonate （BTC） in solution and solvent-free conditions with excellent yields. The results obtained showed the yield increasing on whether a base was used. Finally, an efficient and rapid synthesis of variety carbamate derivatives was developed by the reaction with a high variety of different alcohols, phenols, diols and this intermediate at room temperature with grinding and in solvent-free conditions under microwave irradiation. The presence of various safe bases is shown to be effective in reducing the reaction times, increasing the yields and easing purification. The present method does not involve any hazardous phosgene.

关键词： Bis(trichloromethyl)carbonate Carbamoyl chloride Carbamate Microwave irradiation Solvent-free Grinding

Predicting seismic permanent displacement of soil walls under surcharge based on limit analysis approach

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 747-759页

作者： mohammad Mahdi Aminpour mohammad Maleki Ali ghanbari Faculty of Engineering Bu-Ali Sina University Faculty of Engineering Kharazmi University

Seismic permanent displacement of the soil walls plays an important role in design of these structures. Due to the increase in growth of urban areas and the limitations in use of flat grounds, many structures are built near slopes and retaining walls. During earthquakes, these structures can apply an additional surcharge on the wall. The intensity and location of the surcharge is of considerable importance on the seismic displacements of the soil wall. In this study, by using the limit analysis and upper bound theorem, seismic permanent displacement of the soil wall under surcharge has been analyzed. Thus, a formulation is presented for calculating the yield acceleration and seismic displacement for different surcharge conditions. The effect of seismic acceleration, surcharge intensity, its location and soil properties is investigated. A parameter called the ＂displacement coefficient＂ is proposed, and is a potential modification for Newmark’s sliding-block method.

关键词： limit analysis surcharge soil wall seismic displacement yield acceleration

Numerical Analysis of Crack-Tip Fields using a Meshless Method in Linear Elastic Materials

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Advances in Applied Mathematics and Mechanics 2022年第6期14卷 1509-1534页

作者： Zahra Sheikhi Akbar ghanbari mohammad Karkon Soleyman Ghouhestani Department of Civil Engineering Larestan BranchIslamic Azad UniversityLarestanIran Department of Civil Engineering Fasa UniversityFasaIran

In this paper,the Discrete Least Squares Meshless(DLSM)method is developed to determine crack-tip *** DLSM,the problem domain and its boundary are discretized by unrelated field nodes used to introduce the shape functions by the moving least-squares(MLS)*** method aims to minimize the sum of squared residuals of the governing differential equations at any nodal *** high-continuity shape functions are used,some necessary treatments,including the visibility criterion,diffraction,and transparency approaches,are employed in the DLSM to introduce strong discontinuities such as *** stress extrapolation and J-integral methods are used to calculate stress intensity *** classic numerical examples using three approaches to defining discontinuities in the irregular distribution of nodal points are considered to investigate the effectiveness of the DLSM *** numerical tests indicated that the proposed method effectively employed the approaches to defining discontinuities to deal with discontinuous *** was also demonstrated that the diffraction approach obtained higher accuracy than the other techniques.

关键词： Numerical analysis partial differential equations fracture mechanics meshless method discrete least-squares modification of weight function approaches to defining discontinuities stress intensity factors.

Presenting an engineering classification system for coal spontaneous combustion potential

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International Journal of Coal Science & Technology 2017年第2期4卷 110-128页

作者： Amir Saffari Farhang Sereshki mohammad Ataei Keramat ghanbari Faculty of Mining Petroleum and Geophysics EngineeringShahrood University of Technology Daneshgah Blvd.P.O. Box *** Shahrood Iran HSE Management of Eastern Alborz Coal Mines Company Shahrood lran

The phenomenon of coal spontaneous combustion is one of the common hazards in coal mines and also one of the important reasons for the loss of coal in piles and mines. Based on previous researches, different types of coals have different spontaneous combustion characteristics. For coal loss prevention, a measure is necessary for prediction of coal spontaneous combustion. In this study, a new engineering classification system called ＂Coal Spontaneous Combustion Potential Index （CSCPI）＂ is presented based on the Fuzzy Delphi Analytic Hierarchy Process （FDAHP） approach. CSCPI classifies coals based on their spontaneous combustion capability. After recognition of the roles of the effective parameters influencing the initiation of a spontaneous combustion, a series of intrinsic, geological, and mining characteristics of coal seams are investigated. Then, the main stages of the implementation of the FDAHP method are studied and the weight of each parameter involved is calculated. A classification list of each parameter is formed, the CSCPI system is described, and the engineering classifying system is subsequently presented. In the CSCPI system, each coal seam can be rated by a number from 0 to 100; a higher number implies a greater ease for the coal spontaneous combustion capability. Based on the CSCPI system, the propensity of spontaneous combustion of coal can be classified into three potential levels： low, medium, and high. Finally, using the events of coal spontaneous combustion occurring in one of the Iranian coal mines, Eastern Alborz Coal Mines, an initial validation of the mentioned systematic approach is conducted. Comparison of the results obtained in this study illustrate a relatively good agreement.

关键词： Coal Classification Coal Spontaneous Combustion Potential Index (CSCPI) Fuzzy Delphi AnalyticHierarchy Process (FDAHP) Eastern Alborz Coal Mines

Use of complementary and alternative medicine in general population during COVID-19 outbreak: A survey in Iran

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Journal of Integrative Medicine 2022年第1期20卷 45-51页

作者： Mahlagha Dehghan Alireza ghanbari Fatemeh Ghaedi Heidari Parvin Mangolian Shahrbabaki mohammad Ali Zakeri Nursing Research Center Kerman University of Medical SciencesKerman 76169-13555Iran Anesthesiology and Critical Care Research Center Shiraz University of Medical SciencesShiraz 14336-71348Iran Faculty of Nursing and Midwifery Isfahan University of Medical SciencesIsfahan 81746-73461Iran Non-communicable Diseases Research Center Rafsanjan University of Medical SciencesRafsanjan 77179-33777Iran Social Determinants of Health Research Center Rafsanjan University of Medical SciencesRafsanjan 77179-33777Iran Department of Critical Care Nursing Faculty of Nursing and MidwiferyKerman University of Medical SciencesKerman 76169-13555Iran

Objective: Some epidemic diseases such as coronavirus disease 2019(COVID-19) have caused many physical, psychological, and social challenges, despite the existence of treatment strategies. Many people are looking for complementary and alternative medicine(CAM) to prevent such diseases. The present study was performed to determine how some types of CAM were being used during the COVID-19 epidemic in ***: The present study had a cross-sectional descriptive correlational design. All Iranian residents above 17 years old were eligible to participate in the study. A total of 782 participants completed a demographic information questionnaire, a questionnaire about their use of CAMs and a questionnaire about their satisfaction with the CAMs they used. Web-based sampling was conducted from 20 April 2020 to 20 August ***: Of the participants, 84% used at least one type of CAM during the COVID-19 outbreak. The most used CAMs were dietary supplements(61.3%), prayer(57.9%), and herbal medicines(48.8%). The majority of the participants(50%–66%) have used CAMs to prevent the transmission of COVID-19 or to reduce anxiety caused by the COVID-19 pandemic. CAM use was associated with sex, having children, place of residence, COVID-19 status, and source of gathering information about CAM(P < 0.05). All 32 participants who had been infected with COVID-19 used at least one type of CAM for treatment or alleviation of the disease ***: During the COVID-19 outbreak, some types of CAM, particularly nutritional supplements,medicinal herbs, and prayer, were commonly used to prevent COVID-19 and reduce pandemic-related anxiety.

关键词： Alternative and complementary medicine Coronavirus disease COVID-19 Cross-sectional study

Urban restaurants and online food delivery during the COVID-19 pandemic:a spatial and socio-demographic analysis

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International Journal of Digital Earth 2023年第1期16卷 1725-1751页

作者： Bakhtiar Feizizadeh Davoud Omrazadeh mohammad Ghasemi Samaneh Bageri Tobia Lakes Robert Kitzmann Abolfazl ghanbari Thomas Blaschke Department of Remote Sensing and GIS University of TabrizTabrizIran Department of Geography Humboldt-Universität zu BerlinBerlinGermany IN3 Universitat Oberta de CatalunyaBarcelonaSpain Department of Geoinformatics-Z_GIS University of SalzburgSalzburgAustria

In this research,we analyzed the delivery service areas of restaurants,customer satisfaction,and restaurant sales of urban restaurants during the COVID-19 *** obtained the datasets on food ordering options and restaurant rankings based on Google Maps,Open Street Map,and widely known online food order applications in *** on this analysis we further modeled suitable areas for future extension of *** analyzed the online food order data of restaurants’sales and food delivery reports for 1050 restaurants in the city of *** collected and analyzed data on the restaurant locations,the number of food orders for each restaurant,and the number of customers and their *** results revealed that the spatial dimension of the newly emerging food delivery areas is of utmost importance for the success of *** indicates that an optimal location is not longer only dependent on factors like population density and competitors in the direct vicinity but on the services density even from more distant *** results indicate that an optimized spatial distribution of the restaurants together with efficient quality in services can contribute to optimistic urban development.

关键词： Urban restaurant services area mapping success factors customer satisfaction COVID-19 spatial analysis

Qualitative Priority of Pollutants in Taleghan Catchment Using Analytical Hierarchy Process

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Qualitative Priority of Pollutants in Taleghan Catchment Usi...