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    Investigating short-term and long-term binder performance of high-RAP mixtures containing waste cooking oil

    , Article Journal of Traffic and Transportation Engineering (English Edition) ; Volume 6, Issue 4 , 2019 , Pages 396-406 ; 20957564 (ISSN) Majidifard, H ; Tabatabaee, N ; Buttlar, W ; Sharif University of Technology
    Periodical Offices of Chang- an University  2019
    The environmental and economic benefits of recycling asphalt pavements have received much attention in recent years. Because of the increase in the cost of raw materials and energy carriers, the reuse of large portions of reclaimed asphalt pavement (RAP) is critical in reducing both the cost and environmental footprint of asphalt pavements. High-RAP mixtures are more prone to low temperature cracking and poor mixture workability because of the higher stiffness of RAP binder. Recycling agents are one of the additives which are used to improve these deficiencies. However, there is some ambiguity about the optimum content of recycling agent to assure proper performance of recycled asphalt... 

    Synthesis of quinazolin-4(3H)-one derivatives using heteropolyacids as heterogeneous and recyclable catalysts

    , Article Asian Journal of Chemistry ; Volume 23, Issue 4 , 2011 , Pages 1588-1590 ; 09707077 (ISSN) Allameh, S ; Hashemi, M. M ; Heravi, M. M ; Bamoharram, F. F ; Sharif University of Technology
    A highly efficient and simple procedure for the synthesis of quinazolin-4(3H)-ones from the condensation of 2-aminobenzamide with triethylorthoesters in presence of a catalytic amounts of heteropolyacids in various solvents is reported  

    Magnetic labelled horseradish peroxidase-polymer nanoparticles: A recyclable nanobiocatalyst

    , Article Journal of the Serbian Chemical Society ; Volume 78, Issue 7 , 2013 , Pages 921-931 ; 03525139 (ISSN) Khosravi, A ; Vossoughi, M ; Shahrokhian, S ; Alemzadeh, I ; Sharif University of Technology
    In this study, the reusability and process stability of nano-reengineered horseradish peroxidase was investigated in a fluorescence-based sensing system for hydrogen peroxide determination as a model application. To this end, dendron macromolecules were attached to the enzyme surface through bio-conjugation techniques. The resulting enzyme-polymer nanoparticles, with an average size of 14(±2) nm, showed significant life time and thermal stability. For enzyme recovery and reusability purposes, the enzyme-polymer nanoparticles were labelled with magnetic nanoparticles with a labelling yield of 90 %. These labelled enzyme molecules showed significant process stability, i.e., up to 7 recycling... 

    Manganese and cobalt-terephthalate metal-organic frameworks as a precursor for synthesis of Mn2O3, Mn3O4 and Co3O4 nanoparticles: Active catalysts for olefin heterogeneous oxidation

    , Article Inorganic Chemistry Communications ; Volume 61 , 2015 , Pages 73-76 ; 13877003 (ISSN) Ashouri, F ; Zare, M ; Bagherzade, M ; Sharif University of Technology
    Elsevier  2015
    The thermal decomposition of manganese and cobalt-terephthalate Metal-Organic Framework precursors was utilized as a synthetic route for fabrication of Co3O4, Mn3O4 and Mn2O3 nanoparticles. The prepared metal oxide nanoparticles of Co3O4, Mn3O4 and Mn2O3 possess average size diameter of 40, 60 and 80 nm respectively. The findings demonstrate that spinel structure nanoparticles of Co3O4 and Mn3O4 exhibit efficient catalytic activity toward heterogeneous olefin epoxidation in the presence of tert-butyl hydroperoxide. In... 

    Simple and practical protocol for the silylation of phenol derivatives using reusable NaHSO4 dispread on silica gel under neutral conditions

    , Article Phosphorus, Sulfur and Silicon and the Related Elements ; Volume 182, Issue 1 , 2007 , Pages 175-179 ; 10426507 (ISSN) Khalili, M. S ; Ghafuri, H ; Mojahedi Jahromi, S ; Hashemi, M. M ; Sharif University of Technology
    A simple and mild procedure for the trimethylsilylation of a wide variety of phenols with hexamethyldisilazane (HMDS) on the surface of silica gel dispersed with NaHSO4 at r.t. in a few minutes with excellent yields under neutral conditions is reported. This procedure also allows an excellent selectivity for the silylation of phenols in the presence of amine and CO 2H groups  

    Numerical modelling of the rotary furnace in aluminium recycling processes

    , Article Journal of Materials Processing Technology ; Volume 139, Issue 1-3 SPEC , 2003 , Pages 567-572 ; 09240136 (ISSN) Khoei, A. R ; Masters, I ; Gethin, D. T ; Sharif University of Technology
    In this paper, a numerical simulation involving fluid flow and heat transfer is presented in order to improve the understanding of rotary furnaces. The finite element model is employed to simulate the furnace rotation and analyse the energy flows inside the furnace. A transient dynamic analysis is carried out to predict the evolution and distribution of temperatures in a rotary furnace by modelling and analysing the furnace under different flame positions. The finite element modelling system ELFEN is used to develop models of the furnace. The results clearly indicate the temperature distribution for different angular velocities along with a comparison of temperature variation under different... 

    Developing concrete recycling strategies by utilization of nano-SiO 2 particles

    , Article Waste and Biomass Valorization ; Volume 2, Issue 3 , 2011 , Pages 347-355 ; 18772641 (ISSN) Hosseini, P ; Booshehrian, A ; Madari, A ; Sharif University of Technology
    Nowadays, applying sustainable development strategies in designation and production of various products has attracted specific attention. In order to consider ecological sustainable development for a product, reducing its environmental impacts should be observed. Concrete technology and its products are not exceptions, and therefore, the same has been a concern for concrete industry. Alongside, concrete recycling is one of the measures used to reduce the environmental impacts of concrete products during their life cycle. On the other side, positive performance of silica nano-particles has been proven in numerous researches as one super pozzolanic material. Hence, in this study, we aimed on... 

    Efficient and practical protocol for silylation of hydroxyl groups using reusable lithium perchlorate dispread in silica gel under neutral condition [electronic resource]

    , Article Journal of Organometallic Chemistry ; 2006, Volume 691, Issue 5, Pages 817–820 Azizi, N. (Najmodin) ; Yousefi, R ; Saidi, M. R ; Sharif University of Technology
    A very efficient and mild procedure for the trimethylsilylation of a wide variety of alcohols, including primary, allylic, benzylic, secondary, hindered secondary, tertiary, and phenols with hexamethyldisilazane on the surface of silica gel dispersed with LiClO4 in room temperature at few minutes in excellent yields under neutral conditions is reported. This procedure also allows the excellent selectivity under LP-SiO2 system for silylation of alcohols in the presence of amine and phenolic hydroxy groups  

    Content evaluation of different waste PCBs to enhance basic metals recycling

    , Article Resources, Conservation and Recycling ; Volume 139 , 2018 , Pages 298-306 ; 09213449 (ISSN) Arshadi, M ; Yaghmaei, S ; Mousavi, S. M ; Sharif University of Technology
    Elsevier B.V  2018
    This research aims to expand the body of information that researchers require before starting electronic waste (E-waste) recovery experiments. With this purpose, the basic metal contents, alkalinity, polymer components, iron magnetic separation, metal recovery priority and economic values of different types of waste printed circuit boards (PCBs) were investigated. The selected wastes were computer PCBs (CPCBs), CPCBs with wires, mobile phone PCBs (MPPCBs), television PCBs (TVPCBs), fax machine PCBs (FPCBs), copy machine PCBs (COPCBs) and central processing units (CPUs). These E-wastes were prepared in the three fraction sizes of F1<1 mm, 1 < F2<3 mm, and 3 < F3<8 mm to evaluate the metal... 

    Studies on recycling of zinc-containing waste

    , Article REWAS'04 - Global Symposium on Recycling, Waste Treatment and Clean Technology, Madrid, 26 September 2004 through 29 September 2004 ; 2005 , Pages 2797-2799 ; 8495520060 (ISBN) Taghavi, S. M ; Halali, M ; Sharif University of Technology
    In this report, the possibility of recovering zinc oxide from zinc containing wastes, also the effect of temperature, time and depth of bed on recycling has been studied. Zinc oxide with a purity of 93.5% was obtained  

    Design optimisation of aluminium recycling processes using Taguchi technique

    , Article Journal of Materials Processing Technology ; Volume 127, Issue 1 , 2002 , Pages 96-106 ; 09240136 (ISSN) Khoei, A. R ; Masters, I ; Gethin, D. T ; Sharif University of Technology
    In this paper, a robust design method is developed for reducing cost and improving quality in aluminium recycling. An experimental investigation into the process parameter effects is presented to determine the optimum configuration of design parameters for performance, quality and cost. The Taguchi method is applied initially to plan a minimum number of experiments. Orthogonal array techniques are used to investigate the simultaneous variation of several parameters and the investigation of interactions between parameters. Matrix experiments using standard L4 and L9 orthogonal arrays are employed to evaluate the effects of parameters in recycling of aluminium dross and scrap materials. A... 

    Fabrication and Study of Mechanical Behavior of in Situ Microfibrillar- Reinforced Composites of Polypropylene/Recycled Poly (Ethylene Terephthalate)Toughened with Rubber Particles

    , M.Sc. Thesis Sharif University of Technology Motahari, Tayebeh (Author) ; Bagheri, Reza (Supervisor) ; Alizadeh, Reza (Supervisor)
    The use of polymers is increasing day by day due to low density, reasonable price and ability to produce different products. On the other hand, the accumulation of polymer wastes in nature is one of the environmental concerns in today's world, which is mainly due to the widespread use of polymers in the packaging industry and disposable applications. In order to solve this problem, recycling is recommended as the most appropriate and economical solution. Because in addition to consuming polymer waste, it also saves energy and reduces carbon footprint.Polyethylene terephthalate (PET) is one of the polymeric materials which; It has a special place in the packaging industry and is widely used... 

    Fracture toughness of a hybrid-rubber-modified epoxy. I. Synergistic toughening

    , Article Journal of Applied Polymer Science ; Volume 125, Issue 3 , January , 2012 , Pages 2467-2475 ; 00218995 (ISSN) Abadyan, M ; Bagheri, R ; Kouchakzadeh, M. A ; Sharif University of Technology
    Wiley  2012
    The fracture behavior of a hybrid-rubber-modified epoxy system was investigated. The modified epoxy included amine-terminated butadiene acrylonitrile (ATBN) rubber and recycled tire particles as fine and coarse modifiers, respectively. The results of the fracture toughness (K IC) measurement of the blends revealed synergistic toughening in the hybrid system when 7.5-phr small particles (ATBN) and 2.5-phr large particles (recycled tire) were incorporated. Transmission optical micrographs showed different toughening mechanisms for the blends; fine ATBN particles increased the toughness by increasing the size of the damage zone and respective plastic deformation in the vicinity of the crack... 

    Binary and ternary blends of high-density polyethylene with poly(ethylene terephthalate) and polystyrene based on recycled materials

    , Article Polymers for Advanced Technologies ; Volume 22, Issue 5 , 2011 , Pages 690-702 ; 10427147 (ISSN) Razavi, S ; Shojaei, A ; Bagheri, R ; Sharif University of Technology
    Binary blends of recycled high-density polyethylene (R-HDPE) with poly(ethylene terephthalate) (R-PET) and recycled polystyrene (R-PS), as well as the ternary blends, i.e. R-HDPE/R-PET/R-PS, with varying amounts of the constituents were prepared by twin screw extruder. The mechanical, rheological, thermal, and scanning electron microscopy (SEM) analyses were utilized to characterize the samples. The results revealed that both R-HDPE/R-PET and R-HDPE/R-PS blends show phase inversion but at different compositions. The R-PET was found to have much higher influence on the properties enhancement of the R-HDPE compared to R-PS, but at the phase inverted situation, a significant loss in the tensile... 

    Performance characterization of composite materials based on recycled high-density polyethylene and ground tire rubber reinforced with short glass fibers for structural applications

    , Article Journal of Applied Polymer Science ; Volume 104, Issue 1 , 2007 , Pages 1-8 ; 00218995 (ISSN) Shojaei, A ; Yousefian, H ; Saharkhiz, S ; Sharif University of Technology
    This study addresses the issue of using recycled materials to obtain low-cost structural products for practical applications. Through the use and re-extrusion of virgin high-density polyethylene (HDPE), the effects of the degradation level of HDPE as a matrix phase on its mechanical properties and the mechanical performance of composites produced with the degraded polyethylene have been examined. The degradation level of HDPE caused by reextrusion has been evaluated by the measurement of the melt flow index and mechanical properties of virgin and degraded HDPEs. The results indicate that the modulus and strength of HDPE significantly increase with the addition of polypropylene filled with 30... 

    Particle removal optimization in rotating dissolved air flotation used in paper-recycling wastewater treatment

    , Article Water and Environment Journal ; 2021 ; 17476585 (ISSN) Hasannattaj Jelodar, A ; Amini Rad, H ; Borghei, S. M ; Vossoughi, M ; Rouhollahi, R ; Sharif University of Technology
    John Wiley and Sons Inc  2021
    Rotating dissolved air flotation (RDAF) has been utilized for several decades in paper-recycling wastewater treatment; however, it has rarely been addressed in the literature, which makes research into this system challenging and complicated. However, in this work, a full-scale industrial wastewater treatment system for a paper-recycling mill in Mazandaran province, Iran, was evaluated. Experiments indicated that under the same wastewater and chemical conditions, there are differences in the removal efficiencies. This finding was investigated by conducting simulation in ANSYS CFX R18.0 and experimentation simultaneously. Thus, the main purpose of this research was to optimize the operation... 

    Zinc oxide as a useful and recyclable catalyst for the one-pot synthesis of 2,4,6-trisubstituted-1,3,5-trioxanes under solvent-free conditions

    , Article Industrial and Engineering Chemistry Research ; Volume 52, Issue 28 , 2013 , Pages 9538-9543 ; 08885885 (ISSN) Tayebee, R ; Nasr, A. H ; Rabiee, S ; Adibi, E ; Sharif University of Technology
    Different aliphatic and aromatic aldehydes such as isobutyraldehyde, ethanal, n-propanal, n-butanal, n-hexanal, n-octanal, and substituted benzaldehydes were cyclotrimerized into their corresponding 2,4,6-trialkyl-1,3, 5-trioxanes in the presence of commercial bulk zinc oxide at room temperature under neat conditions within a short span of time with high yield and excellent selectivity. Liquid products were formed as a separate phase and were decanted easily, whereas solid products were isolated by simple extraction. Effect of different additives, mol % of catalyst, kind of substrate, and reaction temperature were examined on the progress of cyclotrimerization reaction  

    Efficient recyclable catalytic system for deoxygenation of sulfoxides: Catalysis of ionic liquid-molybdenum complexes in ionic liquid solution

    , Article New Journal of Chemistry ; Volume 36, Issue 4 , Dec , 2012 , Pages 971-976 ; 11440546 (ISSN) Bagherzadeh, M ; Ghazali Esfahani, S ; Sharif University of Technology
    Three newly synthesized room temperature ionic liquids containing molybdate anion, [DMIm][MoO 2(NCS) 4], [RPy][MoO 2(NCS) 4] (R = butyl or decyl), and previously reported [BMIm][MoO 2(NCS) 4] were used as catalysts for the reduction of sulfoxides. For facilitating the recyclability of the catalysts, the ionic liquids [RMIm][PF 6] and [RPy][PF 6] (RMIm = 1-n-alkyl-3-methylimidazolium, RPy = 1-n-alkylpyridinium) were applied as ionic solvents and toluene is used as solvent for the organic phase. Molybdenum salts immobilized in RTILs constituted a reusable and efficient heterogeneous catalyst system. A maximum conversion (>99%) was achieved for reduction of diphenyl sulfoxide to diphenyl... 

    Comparison of bioleaching ability of two native mesophilic and thermophilic bacteria on copper recovery from chalcopyrite concentrate in an airlift bioreactor

    , Article Hydrometallurgy ; Volume 80, Issue 1-2 , 2005 , Pages 139-144 ; 0304386X (ISSN) Mousavi, S. M ; Yaghmaei, S ; Vossoughi, M ; Jafari, A ; Hoseini, S. A ; Sharif University of Technology
    A mesophilic iron oxidizing bacterium, Acidithiobacillus ferrooxidans, has been isolated (33 °C) from a typical chalcopyrite copper concentrate of the Sarcheshmeh copper mine in the region of Kerman located in the south of Iran. In addition, a thermophilic iron oxidizing bacterium, Sulfobacillus, has been isolated (60 °C) from the Kooshk lead and zinc mine near the city of Yazd in central Iran. Effects of some variable parameters such as solids concentration, temperature and pH on the bioleaching of chalcopyrite obtained from Sarcheshmeh copper mine were investigated. Bioleaching experiments were carried out in two batch airlift bioreactors with a recycling stream. The results indicate that... 

    Design and Evaluation of Cold In-Place Recycling with Emulsion

    , M.Sc. Thesis Sharif University of Technology Bazrafshan Moghadam, Bahador (Author) ; Tabatabaee, Nader (Supervisor)
    Although there are several popular and standardized mix design methods for hot-mix asphalt, there is no universally accepted mix design method for cold in-place recycling (CIR). The varieties of recycling machinery, materials, quality control limitations, etc. have contributed to this problem. Most of CIR laboratory mix designs are based on 4-inch molds and maximum aggregate size of 1inch. The use of single unit train, which is the most common machinery used for CIR, results in poor control of aggregate gradation, especially when distresses such as fatigue cracking exist. This may lead to presence of aggregate sizes larger than 1 inch. In this case the use of 4-in mold is no longer...