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Synthesis of α-aminonitriles using silica-bonded N-propylpiperazine sulfamic acid as a recyclable catalyst

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Chinese Chemical Letters 2012年第10期23卷 1103-1106页

作者： Tahere Rahi mojtaba baghernejad Khodabakhsh Niknam Department of Chemistry Gachsaran BranchIslamic Azad UniversityGachsaranlran Department of Chemistry Faculty of SciencesPersian Gulf UniversityBushehr 75169Iran

α-Aminonitriles were synthesized via a one-pot three-component condensation of aldehydes, amines, and trimethylsilyl cyanide using silica-bonded N-propylpiperazine sulfamic acid （SBPPSA） as a recyclable solid acid ... 详细信息

关键词： Silica-bonded N-propylpiperazine sulfamic acid α-Aminonitriles Aldehydes Amines Catalyst Solid acid

Synthesis of 2-Aryl-l-arylmethyl-lH-1,3-benzimidazole Derivatives Using Silica-bonded PropyI-S-sulfonic Acid as Recyclable Solid Acid Catalyst

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Chinese Journal of Chemistry 2012年第3期30卷 517-521页

作者： Ghaem Ahmadi-Ana,Sayed Mohammad baghernejad,mojtaba Niknam,Khodabakhsh Chemistry Department Gachsaran BranchIslamic Azad UniversityGachsaranIran Chemistry Department Faculty of SciencesPersian Gulf UniversityBushehr75169Iran

A highly selective synthesis of 2-aryl-l-arylmethyl-lH-1,3-benzimidazoles from the reaction of o-phenylene- diamine and aromatic aldehydes in the presence of silica-bonded propyl-S-sulfonic acid （SBSSA） at 80℃ in w... 详细信息

关键词： silica-bonded propyl-S-sulfonic acid aldehydes 2-aryl- 1-arylmethyl-lH-1,3-benzimidazoles,o-phenylenediamine water

硅胶键合N-丙基二乙烯氨基磺酸作为可回收固体酸催化剂催化合成α-氨基腈(英文)

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催化学报 2012年第7期33卷 1095-1100页

作者： Tahere RAHI mojtaba baghernejad Khodabakhsh NIKNAM Department of Chemistry Gachsaran BranchIslamic Azad University Department of Chemistry Faculty of SciencesPersian Gulf University

Silica-bonded N-propyl diethylenetriamine sulfamic acid (SBPDSA) is employed as a recyclable catalyst to synthesize α-aminonitriles. These syntheses involved one-pot condensation of an aldehyde, an amine, and trimethylsilyl cyanide under mild reaction conditions at room temperature. SBPDSA was recycled seven times in the condensation of benzaldehyde, aniline, and trimethylsilyl cyanide without reduction of its catalytic activity.

关键词： silica-bonded N-propyl diethylenetriamine sulfamic acid α-aminonitrile solid acid aldehyde heterogeneous catalyst

((3-(3-硅胶丙基)硫基)丙基)硫酸酯作为可回收催化剂用于合成4,4'-芳亚甲基-双(1H-吡唑-5-醇)(英文)

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催化学报 2011年第9期32卷 1477-1483页

作者： Shekoofeh TAYEBI mojtaba baghernejad Dariush SABERI Khodabakhsh NIKNAM Department of Chemistry Islamic Azad University Gachsaran Branch Gachsaran Iran Department of Chemistry Faculty of Sciences Persian Gulf University

Sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl)ester is employed as a recyclable catalyst for the condensation reaction between aromatic aldehydes and 3-methyl-l-phenyl-5-pyrazolone. This condensation reaction was performed in ethanol under refluxing conditions giving 4,4'-alkylmethylene-bis(3-methyl-5-pyrazolones) in 74-90% yields. The heterogeneous catalyst was recycled and used in eleven runs for the reaction between benzaldehyde and 3-methyl-l-phenyl-5-pyrazolone without losing catalytic activity.

关键词： sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl)ester silica-bonded N-propyl sulfamic acid 3-methyl-l-phenyl-5-pyrazolone aldehydes

Influence of indoor airflow on airborne disease transmission in a classroom

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Building Simulation 2024年第3期17卷 355-370页

作者： mojtaba Zabihi Ri Li Joshua Brinkerhoff School of Engineering Faculty of Applied ScienceUniversity of British ColumbiaKelownaCanada

It has been widely accepted that the most effective way to mitigate airborne disease transmission in an indoor space is to increase the ventilation airflow,measured in air change per hour(ACH).However,increasing ACH did not effectively prevent the spread of *** better understand the role of ACH and airflow large-scale patterns,a comprehensive fully transient computational fluid dynamics(CFD)simulation of two-phase flows based on a discrete phase model(DPM)was performed in a university classroom setting with people *** investigations encompass various particle sizes,ventilation layouts,and flow *** findings demonstrated that the particle size threshold at which particles are deemed airborne is highly influenced by the background flow strength and large-scale flow pattern,ranging from 5µm to 10µm in the cases *** effects of occupants are significant and must be precisely accounted for in respiratory particle transport *** enhanced ventilation design(UFAD-CDR)for university classrooms is introduced that places a premium on mitigating airborne disease *** to the baseline design at the same ACH,this design successfully reduced the maximum number density of respiratory particles by up to 85%.A novel airflow-related parameter,Horizontality,is introduced to quantify and connect the large-scale airflow pattern with indoor aerosol *** underscores that ACH alone cannot ensure or regulate air *** addition to the necessary ACH for air exchange,minimizing horizontal bulk motion is essential for reducing aerosol transmissibility within the room.

关键词： aerosol transmission airflow pattern horizontality COVID-19 simulation classroom ventilation

Exergy Analysis of Charge and Discharge Processes of Thermal Energy Storage System with Various Phase Change Materials:A Comprehensive Comparison

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Journal of Thermal Science 2024年第2期33卷 509-521页

作者： mojtaba TAHERI Fathollah POURFAYAZ Roghayeh HABIBI Akbar MALEKI Department of Renewable Energies and Environment Faculty of New Sciences and TechnologiesUniversity of TehranTehran***Iran Faculty of Mechanical Engineering Shahrood University of TechnologyShahrood***Iran

Thermal energy storage(TES) is of great importance in solving the mismatch between energy production and *** this regard,choosing type of Phase Change Materials(PCMs) which are widely used to control heat in latent thermal energy storage systems,plays a vital role as a means of TES ***,this field suffers from lack of a comprehensive investigation on the impact of various PCMs in terms of *** address this issue,in this study,in addition to indicating the melting temperature and latent heat of various PCMs,the exergy destruction and exergy efficiency of each material are estimated and compared with each ***,in the present work the impact of PCMs mass and ambient temperature on the exergy efficiency is *** results proved that higher latent heat does not necessarily lead to higher exergy ***,to obtain a suitable exergy efficiency,the specific heat capacity and melting temperature of the PCMs must also be *** to the results,LiF-CaF_(2)(80.5%:19.5%,mass ratio) mixture led to better performance with satisfactory exergy efficiency(98.84%) and notably lower required mass compared to other ***,the highest and lowest exergy destruction are belonged to GR25 and LiF-CaF_(2)(80.5:19.5) mixture,respectively.

关键词： exergy analysis phase change materials thermal energy storage exergy efficiency

A new design of parity-preserving reversible multipliers based on multiple-control toffoli synthesis targeting emerging quantum circuits

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Frontiers of Computer Science 2024年第6期18卷 186908-186908页

作者： NOORALLAHZADEH mojtaba MOSLEH Mohammad DATTA Kamalika Department of Computer Engineering Dezful Branch Islamic Azad University German Research Centre for Artificial Intelligence (DFKI) Institute of Computer Science University of Bremen

With the recent demonstration of quantum computers, interests in the field of reversible logic synthesis and optimization have taken a different turn. As every quantum operation is inherently reversible, there is an immense motivation for exploring reversible circuit design and optimization. When it comes to faults in circuits, the parity-preserving feature donates to the detection of permanent and temporary faults. In the context of reversible circuits, the parity-preserving property ensures that the input and output parities are equal. In this paper we suggest six parity-preserving reversible blocks (ZFATSL) with improved quantum cost. The reversible blocks are synthesized using an existing synthesis method that generates a netlist of multiple-control Toffoli (MCT) gates. Various optimization rules are applied at the reversible circuit level, followed by transformation into a netlist of elementary quantum gates from the NCV library. The designs of full-adder and unsigned and signed multipliers are proposed using the functional blocks that possess parity-preserving properties. The proposed designs are compared with state-of-the-art methods and found to be better in terms of cost of realization. Average savings of 25.04%, 20.89%, 21.17%, and 51.03%, and 18.59%, 13.82%, 13.82%, and 27.65% respectively, are observed for 4-bit unsigned and 5-bit signed multipliers in terms of quantum cost, garbage output, constant input, and gate count as compared to recent works.

关键词： reversible circuits parity-preserving NCV library multiple-control Toffoli gates quantum circuits quantum cost

Synchrotron X-ray micro-computed tomography imaging of solid bridges between potash particles near contact points

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Particuology 2024年第9期92卷 24-29页

作者： mojtaba Nabipoor Hassankiadeh Mohammad Mehdi Heydari Carter Blocka Lifeng Zhang Department of Chemical and Biological Engineering University of SaskatchewanSKS7N 5A9SaskatoonCanada

Chemical fertilizers,such as potash,have a strong tendency to cake when exposed to *** this work,a novel synchrotron-based X-ray tomography 3D-imaging technique was for the first time employed to investigate the solid bridge formation from 2D and 3D *** processing and a theoretical model were presented to demonstrate recrystallization near contact points between potash particles during a conventional drying *** effect of initial moisture content on the water activity of surface surrounding the contact points was *** results showed that by increasing the moisture content of particles(3%–5%),the dissolution of sylvite increased and the solid bridge length between potash particles was enlarged from 28μm to 44μm due to supersaturation *** addition,the external porosity of potash particles at the end of drying process decreased from 25.3%to 19.5%for 3%and 5%moisture content,respectively.

关键词： Potash fertilizer Solid bridge Recrystallization Synchrotron X-ray micro-CT imaging Drying process

Use of GIS and BIM for the integration of tunnel designand construction process in conventional tunneling

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Underground Space 2024年第3期16卷 261-278页

作者： Mansour Hedayatzadeh Jamal Rostami Vasilis Sarhosis mojtaba Nematollahi Nabiollah Hajiantilaki Abouzar Shafiepour University of Leeds Leeds LS29JTUK Colorado School of Mines GoldenCO 80401USA University of Minho Guimaraes 4800-058Portugal General Mechanic Company Tehran ***Iran Ettehadrah Consulting Engineers Tehran Q83GVWVIran

This paper presents the development of a framework for the parametric design of tunnels using geographic information system (GIS)mapping and building information modelling (BIM). According to the framework, a parametric representation of each system component (e.g., layers of rock mass, size of excavation, topography, fault geometry, primary lining, secondary lining, rock bolts, etc.) can beincorporated in the GIS model with high levels of detail and used for the automatic generation of numerical models for the design oftunnel construction. This parametric evaluation allows the designer to consider several levels of detail for each component, for the effi-cient design and process optimization in conventional tunneling. Information between parametric analysis and numerical simulations canbe freely exchanged with significantly reduced computational effort while results can be exported into BIM. It is anticipated that the proposed framework could lead to a comprehensive, yet efficient analysis of complex conventional tunneling project using parametric evaluations at the early design stages.

关键词： Geographic information system Building information modelling Conventional tunneling Numerical simulations Parametric analysis