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Chemical functionalization of chitosan biopolymer and chitosan-magnetite nanocomposite with sulfonic acid for acid-catalyzed reactions

中国东盟报道（英文） 2024年第6期 48页

作者： Dato’ Abdul majid Ahmad Khan

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Chinese Journal of Chemical Engineering 2021年第11期34卷 154-161页

作者： majid Masteri-Farahani Samaneh Shahsavarifar Research Institute of Green Chemistry Faculty of ChemistryKharazmi UniversityTehranIran

Chemical functionalization of chitosan biopolymer and chitosan-magnetite nanocomposite was performed with sulfonic acid functional groups to achieve new solid acid *** sulfonic acid functional groups were created through the ring opening nucleophilic reaction of amine groups of chitosan with 1,4-butane *** transform infrared spectroscopy(FT-IR)and X-ray photoelectron spectroscopies(XPS)verified the successful sulfonic acid functionalization of *** obtained sulfonic acid functionalized chitosan-magnetite nanocomposite showed superparamagnetic properties according to the vibrating sample magnetometry analysis and exhibited magnetic separation feature from dispersed *** adsorption-desorption analysis indicated the increase in surface area after formation of chitosan-magnetite nanocomposite and functionalization with sulfonic *** of the prepared solid acids exhibited high catalytic activities in the acid-catalyzed acetic acid esterification with n-butanol and benzaldehyde acetalization with ethylene glycol as model ***,they can be reused several times without considerable loss of their activities.

关键词： Chitosan Magnetite Nanostructure Sulfonic acid Catalysis Esterification

Clear-water scour around semi-elliptical abutments with armored beds

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International Journal of Sediment Research 2010年第3期25卷 233-244页

作者： Hossein AFZALIMEHR Abdolreza Kabiri samani Mehrnoosh MAHERANI Department of Water Engineering Isfahan University of Technology Department of Civil Engineering Isfahan University of Technology

Experimental study has been carried out under a clear-water scour condition to explore the local scour around semi-elliptical model bridge abutments with armor-layer bed, compared with the local scour process around semi-circular abutment. Two types of model bridge abutments, namely semi- elliptical and semi-circular abutments have been used in this experimental study. The model abutments had a ratio of streamwise length of abutment to the length of abutment transverse to the flow of 2 for semi-circular abutments and 3 for semi-elliptical abutments. In total, 50 Experiments have been designed and conducted under different flow conditions such as bed shear velocities, flow depth, and dimensions of bridge abutment model, as well as grain size of the bed material. Based on these experiments, the scour process around bridge abutments has been assessed. The dependence of the equilibrium scour depth of the scour hole on hydraulic variables has been studied. Empirical equation describing the equilibrium scour depth of the scour hole around bridge abutments has been developed.

关键词： Armor-layer Equilibrium scour depth Local scour Particle grain size Semi-circular abutment Semi-elliptical abutment Shear velocity

Shoreline spatial and temporal response to natural and human effects in Boujagh National Park, Iran

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International Journal of Sediment Research 2021年第5期36卷 582-592页

作者： Morteza Karimi Jamal Mohammad Vali samani Mehdi Mazaheri Department of Water Structures Tarbiat Modares University Academic Center for Education Culture and Research (ACECR) Environmental Research Institute

Shoreline variation and river deltas are among the most dynamic systems in marine environments. The related different variations in spatial and temporal scales play significant roles in land planning and different management applications. Modeling the dynamics of seashore of Boujagh National Park(BNP)which is located on the southern coast of the Caspian Sea in the Sefidrud Delta(SD), considering natural and anthropogenic factors, was the main objective of the current study. To achieve this goal, a combination of remote sensing data, historical data, and numerical simulations was utilized. The BNP covers an area of 3,270 ha and includes two international wetlands, Boujagh and Kiashahr. In earlier periods, this area faced severe morphological changes whereas recently its shoreline has experienced gradual variations. Accordingly, at the first stage, the shoreline variation from 2006 to 2017 was extracted by processing and classifying Operational Land Imager(OLI) and Thematic Mapper(TM) images from Landsat satellites using the Maximum Likelihood approach. In the second stage, the two dimensional MIKE21 model was utilized to identify wave and coastal current patterns and parameters for the year ***, the results showed that, the shoreline of the BNP is affected by several natural and anthropogenic factors. Seaward advancement of the shoreline occurred in zones A(east zone) and C(west zone) due to Caspian Sea Level drop and sedimentation while retreating occurred at Zone B(north zone) influenced by wave and current patterns and reduction of the Sefidrud River flows. Also, the results imply that maintaining the existing conditions results in the disappearance of a considerable part of the ecological area in the BNP. Hence, to manage and preserve the coastline of the BNP complying with the current anthropogenic and natural factors, it is vital to take necessary management measures.

关键词： Shoreline dynamics Boujagh National Park Remote sensing MIKE21 Wave and current

Relative Canonical Modules and Some Duality Results

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Algebra Colloquium 2019年第2期26卷 351-360页

作者： majid Rahro Zargar Department of Engineering Sciences Faculty of Advanced Technologies University of Mohaghegh Ardabili Namin Ardabil Iran Department of Engineering Sciences Faculty of Advanced Technologies Sabalan University of Advanced technologies (SUAT) Namin Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM)

Let (R, m) be a relative Cohen–Macaulay local ring with respect to an ideal a of R and set c to be ht a. We investigate some properties of the Matlis dual of the R-module H^ca(R), and we show that such modules behave like canonical modules over Cohen–Macaulay local rings. Moreover, we provide some duality and equivalence results with respect to the module H^ca(R)^∨, and these results lead us to achieve generalizations of some known results, such as the local duality theorem, which have been provided over a Cohen–Macaulay local ring admiting a canonical R-module.

关键词： local cohomology canonical module complex relative Cohen-Macaulay module

An Assessment of Resilience Capacities in Local Disaster Management:A Case Study of Tabriz, Iran

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Chinese Journal of Urban and Environmental Studies 2023年第1期11卷 6-26页

作者： Ahmad asadi Bozorgmehr University of Qaenat Shirazi Square

Regarding the approach of reducing risks of settlements, a system is considered to be resilient if it can address temporary and permanent risks and adapt itself to rapidly changing conditions without losing its functionality. To this end, a dynamic management approach on a local scale is needed for realizing resilience. Due to the importance of local management in improving resilience in cities, this study aims to assess the resilience capacity of the local risk management in terms of exposure to various crises in Tabriz, Iran. The findings in this study show that integrity and coordination in decision-or policy-making, enhancement of organizational and local capacities, and confrontation or rehabilitation approaches in critical conditions and after that are not desirable in Tabriz. Also, the centralized and top-down approaches lead to no proper local planning and management that can facilitate the resilience measures. In light of no spatial equilibrium in Tabriz and the inefficiency of conventional planning and management systems,technocrat-oriented and top-down, changing the management practices and emphasizing the local and bottom-up approach are necessary for the thorough understanding of facilities and limitations and implementation of realistic planning.

关键词： Local management urban resilience crisis Tabriz

Assessment of the Environmental Impacts of COVID-19 in Urban Areas—A Case Study of Iran

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Journal of Environmental Protection 2021年第5期12卷 328-344页

作者： Fatemeh Rezaeitavabe majid Sartaj Mohammad asadi Tokmedash Nasser Talebbeydokhti Department of Civil and Environmental Engineering Shiraz University Shiraz Iran Department of Civil Engineering University of Ottawa Ottawa Canada Department of Chemical Engineering College of Engineering University of Tehran Tehran Iran

Abstract The Severe Acute Respiratory Syndrome-Coronavirus Outbreak 2019 (COVID-19) has caused worldwide concern and has affected all aspects of human life. The study objective is to assess and evaluate the direct and indirect positive and negative environmental effects of COVID-19 in urban areas. Collected data for Iran as a case study is presented, comprehensively completing the dynamic effect of COVID-19 on the environment. The analysis results indicate that despite the temporarily positive effects of coronavirus on the environment, such as improvement in air quality (15% - 20% reduction of NO2 in Tehran), environmental noise reduction, cleaner beach and coastal areas due to implementing lockdowns, there are negative short- and long-term effects such as excessive water consumption (10% - 40% increase in Iranian cities), reduce in waste recycling and significant increase in both residential and medical solid waste generation (10% - 77% increase in medical waste generation and 10% - 50% increase residential waste generation in Iranian cities), which leads to pollution or/and degradation of the environment (air, water and land). Moreover, with the global economic relaunching relaunch in most countries in the coming months, it could result in adverse effects such as increase in the greenhouse gas emissions. Assessment of environmental impacts, type and scale, could help for better planning and mitigation of the future pandemics.

关键词： COVID-19 Coronavirus Pandemic Environmental Impacts Iran

Numerical simulation of sanding using a coupled hydro-mechanical sand erosion model

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第4期12卷 811-820页

作者： majid Fetrati Ali Pak Department of Civil Engineering Sharif University of TechnologyTehranIran

Mechanical failure of materials adjacent to the production cavity and material disaggregation caused by fluid drag are considered as the most important parameters that affect sand *** light of such factors,the coupling of two mechanisms-mechanical instability and hydrodynamic erosion-is indispensable in order to model this phenomenon *** paper examines the applicability of a coupled hydro-mechanical erosion criterion for simulating sand production using the finite element *** porous medium was considered fully *** onset of sanding and production of sand were predicted by coupling mechanical failure and subsequent erosion of the grain particles utilizing a sanding *** consider the erosion process,the Papamichos and Stavropoulou(1998)’s sand erosion criterion was incorporated into the finite element *** Lagrangian-Eulerian(ALE)adaptive mesh approach was used to account for large amounts of erosive material ***,in order to address the problem of severe mesh distortion,the“mesh mapping technique”was *** production in a horizontal wellbore and in a field case was simulated to demonstrate capabilities of the proposed *** addition,principal parameters affecting sand production,including in situ stresses,cohesion,perforation orientation,and drawdown were *** results indicated the efficiency of the model used in evaluation of sanding in the *** studies indicated that in situ stresses and formation cohesion could be considered as dominant factors affecting the amount of sand production.

关键词： Sand production Finite element method Sanding criterion Hydro-mechanical coupling

Effects of green iron nanoparticles on iron changes and phytoavailability in a calcareous soil

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Pedosphere 2021年第5期31卷 761-770页

作者： Akbar SOLIEMANZADEH majid FEKRI Department of Soil Science College of AgricultureShahid Bahonar University of KermanKerman ***(Iran)

Green iron nanoparticles(Fe NPs)can be a practical solution to combat iron(Fe)deficiency in calcareous agricultural *** main aim of the present work was to assess the effects of green Fe NPs on Fe availability in calcareous *** this purpose,green Fe NPs were synthesized using green tea(G-Fe NPs),Shirazi thyme(T-Fe NPs),walnut green hull(W-Fe NPs),and pistachio green hull(P-Fe NPs)extracts and applied as a source of Fe fertilizer to sorghum(Sorghum bicolor ***)*** of X-ray diffraction(XRD),scanning electron microscopy(SEM),and dynamic light scattering(DLS)indicated that the green Fe NPs were amorphous in nature and the polyphenols obtained from plant-part extracts acted as both capping and reducing *** to the behavior of Fe-ethylenediamine-N,N-bis(2-hydroxyphenyl)acetic acid(Fe-EDDHA)in calcareous soils,G-Fe NPs,T-Fe NPs,W-Fe NPs,and P-Fe NPs increased Fe release compared with the control and FeSO_(4) *** Fe release data fitted well to the power function,intra-particle diffusion,and Elovich kinetic *** to the pot experiment,the increment in soil Fe availability upon Fe-EDDHA and Fe NPs application led to an increase in Fe uptake,growth,and photosynthetic pigment contents of the sorghum *** further research is needed to evaluate the residual effect and environmental impact of green Fe NPs,they may be an appropriate substitute for traditional Fe fertilizers in calcareous soils.

关键词： chlorophyll content Fe fertilizer Fe release green chemistry natural polyphenols sorghum

Seismic vulnerability assessment of urban buildings and traffic networks using fuzzy ordered weighted average

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Journal of Mountain Science 2019年第3期16卷 677-688页

作者： Yasaman asadi Najmeh Neysani SAMANY Keyvan EZIMAND Department of Remote Sensing and GIS Faculty of GeographyUniversity of Tehran Remote Sensing and GIS Center Faculty of Earth ScienceUniversity of Shahid Beheshti

Urban buildings and urban traffic network are considered as the vital arteries of cities which have particular effects especially after the crisis in the search and rescue operations. The aim of this study is to determine the vulnerability of urban areas especially, buildings and traffic networks using multicriteria geographic information systems and decisionmaking methods. As there are many effective criteria on the seismic vulnerability that they have uncertain and vague properties, the method of this paper is applying fuzzy ordered weighted average(OWA) to model the seismic vulnerability of urban buildings and traffic networks in the most optimistic and pessimistic states. The study area is district 6 of Tehran that is affected by the four major faults, and thus will be threatened by the earthquakes. The achieved results illustrated the vulnerability with different degrees of risk levels including very high, high, medium, low and very low. The results show that in the most optimistic case 14% and in the pessimistic case 1% of buildings tolerate in very low vulnerability. The vulnerability of urban street network also indicates that in the optimistic case 12% and in the pessimistic case at most 9% of the area are in appropriate condition and the North and NorthEast of the study area are more vulnerable than South of it.

关键词： Earthquake Vulnerability Assessment Urban buildings Traffic network Multi-Criteria Decision Analysis(MCDA) Fuzzy-OWA