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RAPID AND FACILE SYNTHESIS OF ACYL AZIDES FROM ACYL HaliDES USING A POLYMER-SUPPORTED AZIDE ION UNDER HETEROGENEOUS CONDITIONS

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Chinese Journal of Polymer Science 2013年第7期31卷 1002-1010页

作者： mohammad ali Karimi Zarchi Saeed Barani Department of Chemistry College of SciencesYazd University

In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly（N-methyl-4- vinylpyridinium） azide ion, [Pa-VP]N3 is prepared and used as an efficient polymeric reagent for synthesis of acyl azides from acyl halides at room temperature under heterogeneous conditions. Various benzoyl halides, with electron-withdrawing groups as well as electron-donating groups, were transformed into the corresponding benzoyl azides in high to excellent yields in short reaction times. The acyl azide products were characterized by FT-IR, and some of them were also characterized by IH- and/or 13C-NMR spectroscopy, and physical properties were compared to literature values of known compounds. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. Relative to the reported methods, the present method has the advantages of operational simplicity, mild reaction conditions, fast reaction rates, simple reaction work-up and lower hazardous and potentially explosive nature. Also the present method is the first procedure for the synthesis of acyl azides from acyl halides by using a polymer-supported azide ion under heterogeneous conditions.

关键词： Acyl azide Acyl halide Polymeric reagent Heterogeneous condition.

Precipitation of hematite nanoparticles via reverse microemulsion process

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Journal of Natural Gas Chemistry 2011年第6期20卷 687-692页

作者： mohammad Reza Housaindokht ali Nakhaei Pour Bimolecular Research Center Department of ChemistryFerdowsi University of MashhadP.O.Box:91775-1436MashhadIran

Hematite nanoparticles have been successfully synthesized via two processing routes：（i） conventional precipitation route and （ii） reverse microemulsion *** particle precipitation was carried out in a semibatch reactor.A microemulsion system consisting of water,chloroform,1-butanol and surfactant was loaded with iron nitrates to form iron nanoparticles *** precipitation was performed in the single-phase microemulsion operating *** technical surfactants,with different structure and HLB value are *** influence of surfactant characterization on the size of produced iron oxide particle has been studied to gain a deeper understanding of the important controlling mechanisms in the formation of nanoparticles in a *** electron microscopy （TEM）,surface area,pore volume,average pore diameter,pore size distribution and XRD were used to analyze the size,size distribution,shape and structure of precipitated iron nanoparticles.

关键词： iron nanoparticles microemulsion hematite

Optimization of cement-based grouts using chemical additives

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 623-637页

作者： mohammad Reza Azadi ali Taghichian ali Taheri Faculty of Science and Technology Federation University Australia Mewbourne School of Petroleum and Geological Engineering University of Oklahoma Department of Earth Science and Engineering Imperial College

Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after *** are many methods of *** grouting is one of the most common types in which the grout material is injected to the pore spaces of the *** grouting operations,the grout quality is important to achieve the best *** are four main characteristics for a grout mixture including bleeding,setting time,strength,and *** this paper,we try to build some efficient grouting mixtures with different water to cement ratios considering these *** ingredients of grout mixtures built in this study are cement,water,bentonite,and some chemical additives such as sodium silicate,sodium carbonate,and triethanolamine(TEA).The grout mixtures are prepared for both of the sealing and strengthening purposes for a structural *** of each abovementioned ingredient is profoundly *** each ingredient may have positive or negative aspect,an optimization of appropriate amount of each ingredient is *** optimization is based on 200 grout mixture samples with different percentages of ***,some of these grout mixtures are chosen for the introduced *** should be mentioned that grouting operations depend on various factors such as pressure of injection,ground structure and grain size of ***,quality of a grout can be helpful to make an injection easier and *** example,during the injection,a wrong estimated setting time can destroy the injected grout by washing the grout or setting early which prevents *** paper tries to show some tests in easy way to achieve a desirable sample of grout.

关键词： Permeation grouting Bleeding Setting time Chemical additives Cement-based grout

Experimental investigation of flow and distortion mitigation by mechanical vortex generators in a coupled serpentine inlet-turbofan engine system

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Chinese Journal of Aeronautics 2020年第5期33卷 1375-1391页

作者： Iman MAGHSOUDI mohammad ali VAZIRY Mostafa MAHMOODI Department of Aerospace Malek-Ashtar University of TechnologyTehran 158751774Iran Department of Aerospace Malek-Ashtar University of TechnologyIsfahanShahinshahr 115/83145Iran

The performance of compact,aggressive ducts in advanced propulsion systems is limited by the internal flow separation coupled with the formation of secondary counter-rotating vortices that give rise to intensive flow distortions at the duct *** experimental investigation was conducted to study the flow field and passive suppression of flow separation and Aerodynamic Interface Plane (aiP) distortion in a serpentine air inlet *** were performed by a turbofan engine at several Engine Operating Points (EOPs) from 56%(idle) to 100%(max).A large total pressure deficit region arose at the upper part of the aiP,which was associated with the upper surface flow *** the new mechanical S-type vortex generators in two longitudinal positions (VGl and VG2),separation and loss were diminished at the upper part of the duct and *** VG2 arrangement attained the maximum reductions in distortion coefficients which were 73.72%,60.7% and 37.8% in DC(90°),DC(60°) and△P_C/P metrics,*** the next step of the study,some unsteady aspects of the flow field were analyzed inside the *** separation onset and reattachment points were determined by the standard deviation of static pressure on the upper *** aiP spectral distribution showed that the boundary of low pressure and high pressure recovery regions was dominated by the maximum ***,the PSD diagram of several probes at aiP revealed the vortex shedding frequency and its higher harmonics at separation *** energy content of distinct unsteady spectral features in the bare configuration was significantly reduced using VGs,which showed the improvement of flow at the duct exit.

关键词： Distortion coefficient Power spectral density Serpentine inlet Total pressure Vortex generators

Modeling the Facies of Reservoir Using Seismic Data with Missing Attributes by Dissimilarity Based Classification

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Journal of Earth Science 2017年第4期28卷 703-708页

作者： Majid Bagheri mohammad ali Riahi Institute of Geophysics University of TehranTehran 14115-6466Iran

Using seismic attributes as features for classification in feature space, in various aims such as seismic facies analysis, is conventional for the purpose of seismic interpretation. But sometimes seismic data may have no attributes or it is hard to define a small and relevant set of attributes in some applica- tions. Therefore, employing techniques that perform facies modeling without using attributes is neces- sary. In this paper we present a new method for facies modeling of seismic data with missing attributes that called dissimilarity based classification. In this method, classification is based on dissimilarities and facies modeling will be done in dissimilarity space. In this space dissimilarities consider as new features instead of real features. A support vector machine as a powerful classifier was employed in both feature space （feature-based） and dissimilarity space （feature-less） for facies analysis. The proposed feature-less and feature-based classification is applied on a real seismic data from an Iranian oil field. Facies model- ing using seismic attributes provide better results, but the feature-less classification outcome is also satis- factory and the facies correlation is acceptable. Indeed, the power of attributes to discriminate different facies causes to that facies analysis using attributes provide more reliable results comparing to feature- less facies analysis.

关键词： facies analysis dissimilarity feature seismic attributes classification support vector- classifier.

Performance improvement of ionic surfactant flooding in carbonate rock samples by use of nanoparticles

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Petroleum Science 2016年第4期13卷 725-736页

作者： mohammad ali Ahmadi James Sheng Department of Petroleum Engineering Ahwaz Faculty of Petroleum Engineering Petroleum University of Technology Petroleum Department Texas Tech University

Various surfactants have been used in upstream petroleum processes like chemical flooding. Ultimately, the performance of these surfactants depends on their ability to reduce the interfacial tension between oil and water. The surfactant concentration in the aqueous solution decreases owing to the loss of the surfactant on the rock surface in the injection process. The main objective of this paper is to inhibit the surfactant loss by means of adding nanoparticles. Sodium dodecyl sulfate and silica nanoparticles were used as ionic surfactant and nanoparticles in our experiments, respectively. AEROSIL~？ 816 and AEROSIL~？200 are hydrophobic and hydrophilic nanoparticles. To determine the adsorption loss of the surfactant onto rock samples, a conductivity approach was used. Real carbonate rock samples were used as the solid phase in adsorption experiments. It should be noted that the rock samples were water wet. This paper describes how equilibrium adsorption was investigated by examining adsorption behavior in a system of carbonate sample（solid phase） and surfactant solution（aqueous phase）. The initial surfactant and nanoparticle concentrations were 500–5000 and 500–2000 ppm, respectively. The rate of surfactant losses was extremely dependent on the concentration of the surfactant in the system, and the adsorption of the surfactant decreased with an increase in the nanoparticle concentration. Also, the hydrophilic nanoparticles are more effective than the hydrophobic nanoparticles.

关键词： Adsorption Hydrophobic silica nanoparticles Hydrophilic silica nanoparticles Ionic surfactant Carbonate rock

On the potential of alyssum as an herbal fiber to improve the filtration and rheological characteristics of water-based drilling muds

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Petroleum 2022年第4期8卷 509-515页

作者： mohammad Amin Ebrahimi ali Sanati Department of Petroleum Engineering Amirkabir University of TechnologyTehranIran Petroleum and Petrochemical Engineering School Hakim Sabzevari UniversitySabzevarIran

Drilling muds play an important role in drilling and production operations so that the degree of success in such operations is determined by the proper design of these *** optimize drilling operations and avoid excessive expenditure,it is essential to prepare a drilling mud that is both cheap and *** additives are typically used in drilling systems to improve these fluids'capabilities in terms of hole cleaning capacity,filtration control,viscosity,yield point,heat transfer,***,environmental concerns,cost of production,and availability are always considered challenging *** study introduces an eco-friendly herbal fiber in powder and regular forms as a potential alternative to other chemical *** do so,alyssum homolocarpum seed mucilage was added with different concentrations to the water-based drilling muds,and its rheological behavior,filtration control,and the induced formation damage were examined and the optimum concentration was *** results of this study revealed the advantages of the drilling muds formulated with alyssum in terms of filtration control,rheology,formation damage,and greenness.

关键词： Drilling fluid alyssum Herbal fiber Rheology Filtration contro

Kinetics and mechanism of titanium hydride powder and aluminum melt reaction

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 165-172页

作者： ali Rasooli Mehdi Divandari Hamid Reza Shahverdi mohammad ali Boutorabi School of Metallurgy and Materials Engineering Member of Center of Excellence for Advanced Material and Processing (CEAMP) Iran University of Science and Technology Tehran 16844 Iran Department of Materials Faculty of Engineering Tarbiat Modaress University Tehran 14115-143 Iran

Based on the measurement of the released hydrogen gas pressure （PH2）, the reaction kinetics between TiH2 powder and pure aluminum melt was studied at various temperatures. After cooling the samples, the interface of TiH2 powder and aluminum melt was studied. The results show that the-time curves have three regions; in the first and second regions, the rate of reaction conforms zero and one order, respectively; in the third region, the hydrogen gas pressure remains constant and the rate of reaction reaches zero. The main factors that control the rate of reaction in the first and second regions are the penetration of hydrogen atoms in the titanium lattice and the chemical reaction between molten aluminum and titanium, respectively. According to the main factors that control the rate of reaction, three temperature ranges are considered for the reaction mechanism：（a） 700-750°C, （b） 750-800°C, and （c） 800-1000°C. In the first temperature range, the reaction is mostly under the control of chemical reaction; at the temperature range of 750 to 800°C, the reaction is controlled by the diffusion and chemical reaction; at the third temperature range （800-1000°C）, the dominant controlling mechanism is diffusion.

关键词： titanium hydride aluminum reaction kinetics reaction rate constants

A novel ensemble model for predicting the performance of a novel vertical slot fishway

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1418-1444页

作者： Aydin SHISHEGARAN mohammad SHOKROLLAHI ali MIRNOROLLAHI Arshia SHISHEGARAN mohammadreza mohammad KHANI Deparlment of Water and Environmental Engineering School of Civil EngineeringIran University of Science and TechnologyTehran ***Iran Department of Water and Environmental Engineering School of Civil EngineeringSemnan UniversitySemnan 35131-19111Iran Department of Water and Enironmental Engineering School of Civil EngineeringIslamic Azad University Central Tehran BranchTehran ***Iran School of Progress Engineering Iran University of Science and TechnologyTehran ***Iran

We investigate the performance of a novel vertical slot fishway by employing finite volume and surrogate *** linear regression,multiple log equation regression,gene expression programming,and combinations of these models are employed to predict the maximum turbulence,maximum velocity,resting area,and water depth of the middle pool in the *** statistical parameters and error terms,including the coefficient of determination,root mean square error,normalized square error,maximum positive and negative errors,and mean absolute percentage error were employed to evaluate and compare the accuracy of the *** also conducted a parametric *** independent variables include the opening between bafles(OBB),the ratio of the length of the large and small baffles,the volume flow rate,and the angle of the large *** results show that the key parameters of the maximum turbulence and velocity are the volume flow rate and OBB.

关键词： novel vertical slot fishway parametric study finite volume method ensemble model gene expression programming