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    In-situ formation and entrapment of Ag/AgCl photocatalyst inside cross-linked carboxymethyl cellulose beads: A novel photoactive hydrogel for visible-light-induced photocatalysis

    , Article Journal of Photochemistry and Photobiology A: Chemistry ; Volume 398 , 2020 Heidarpour, H ; Golizadeh, M ; Padervand, M ; Karimi, A ; Vossoughi, M ; Tavakoli, M. H ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In this work, a novel photoactive cellulose-based hydrogel was prepared by simultaneous AgCl formation and entrapment inside Al (III) and Fe (III) cross-linked carboxymethyl cellulose beads. Physio-chemical and optical properties of the synthesized composites were well characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, elemental mapping, Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL), and diffuse reflectance spectroscopy (DRS). The photocatalytic activity of hydrogels was evaluated by the degradation of rhodamine B (RhB), as a model environmental pollutant. A comparative study showed that... 

    Modified CMC. 4. Ceric-initiated methacrylonitrile graft polymerization onto carboxymethylcellulose

    , Article Journal of Polymer Materials ; Volume 21, Issue 4s , 2004 , Pages 351-359 ; 09738622 (ISSN) Pourjavadi, A ; Zohuriaan Mehr, M. J ; Pooraghaberar, A ; Hosseinzadeh, H ; Sharif University of Technology
    2004
    Abstract
    Graft copolymerization of methacrylonitrile (MAN) onto carboxymethylcellulose (CMC) was carried out under argon atmosphere in a homogeneous aqueous medium by using ceric ammonium nitrate (CAN) as an initiator. The FTIR spectroscopy and solubility characteristics of the products were used for confirming the graft copolymer formation. The effect of the concentration of the initiator, monomer and polysaccharide as well as the reaction time and temperature on the graft copolymerization reactions were investigated to achieve the optimum grafting conditions (i.e. CAN 0.00065 mol/L, MAN 0.85 mol/L, CMC 1% W/V, reaction temperature 45°C, and reaction time 2 h). According to the empirical rates of... 

    Modified CMC. 3. Carboxymethylcellulose-g-poly(acrylamidrazone) as a new metal adsorbent

    , Article Journal of Polymer Materials ; Volume 21, Issue 3 , 2004 , Pages 315-320 ; 09738622 (ISSN) Zohuriaan Mehr, M. J ; Pourjavadi, A ; Salehi Rad, M ; Sharif University of Technology
    2004
    Abstract
    A new poly(acrylamidrazone) chelating resin was prepared from carboxymethylcellulose (CMC) via a two-step process. First, acrylonitrile was graft polymerized onto the substrate. The CMC-polyacrylonitrile graft copolymer was then treated with hydrazine to yield a triply modified cellulose containing amidrazone functional groups. The resin was characterized using infrared spectroscopy. The sorption capacity of the resin towards bivalent metal ions was evaluated versus variation of pH and hydrochloric acid concentration. The adsorption capacities at pH 6 were found to be in order Cu2+> Zn2+>Cd2+>Co2+>Ni2+. The metal ion sorption capacities were varied in the range of 2.0-20.0 mmol metal per... 

    Influences of polymer-surfactant interaction on the drop formation process: an experimental study

    , Article Langmuir ; Volume 37, Issue 3 , 2021 , Pages 1025-1036 ; 07437463 (ISSN) Dastyar, P ; Salehi, M. S ; Firoozabadi, B ; Afshin, H ; Sharif University of Technology
    American Chemical Society  2021
    Abstract
    The interaction between polymer and surfactant molecules affects the physical properties of liquids, which could be of great importance in an abundance of processes related to drop formation. Polymer and surfactant concentration is a factor that dramatically impacts the shape of molecular networks formed in the fluid bulk and the characteristics of a forming drop. In this study, the deformation and detachment of aqueous carboxymethyl cellulose (CMC) solutions' drops containing different concentrations of sodium dodecyl sulfate (SDS) are studied experimentally. Our purpose is to determine the effects of CMC and SDS concentrations on the parameters related to the formation process, including... 

    Application of Magnetic Grapheme Oxide Coated by Modified Carboxymethyl Cellulose as a Nanoadsorbent to Dye Removal

    , M.Sc. Thesis Sharif University of Technology Shirzadeh Bilehsavar, Behrouz (Author) ; Pourjavadi, Ali (Supervisor) ; Alamolhoda, Ali Asghar (Supervisor)
    Abstract
    There are many industries in the world that produce colorized wastewater. Because of the complex structure and good solubility of dyes, such industries have problem treating this wastewaters. On the other hand, because of the toxicity of these materials for water living, dye removal from discharged wastewater of these industries is very important. In recent years, researchers have become interested in the synthesis of dye Nano adsorbents and they have published many works on this subject. The important parameters in the synthesis of such adsorbent include; non-toxicity, high adsorption capacity and easy separation. In this project, cellulose was extracted from bagasse and then CMC was... 

    Production of Biocellulose Nanofibers by Gluconacetobacter and Evaluation of the Release of the Azithromycin Antibiotic Loaded on It in a Simulated Gastric Fluid

    , M.Sc. Thesis Sharif University of Technology Gholizadeh, Yousef (Author) ; Alemzadeh, Iran (Supervisor)
    Abstract
    Bacterial cellulose is a kind of cellulose with high purity and Crystallization, which is mainly produced by gram-negative bacteria in aqueous media containing a sugar source.Cellulose produced by this method is in the form of nanofibers and one of its considerable aspects, nowadays, is that this kind of cellulose is used as a drug carrier system for treating various diseases. Azithromycin is used as an antibiotic for the treatment of a wide range of bacterial infections. In this study, cellulose nanofibers were synthesized by gluconacetobacter and its surface was modified using 0.5, 1, and 1.5 mg/ml carboxymethylcellulose solution in sodium acetate buffer. Then, by stabilizing azithromycin... 

    CMC-g-poly (sodium acrylate)/kaolin superabsorbent hydrogel composites: Synthesis, characterization and swelling behaviour

    , Article Polymers and Polymer Composites ; Volume 14, Issue 7 , 2006 , Pages 701-712 ; 09673911 (ISSN) Pourjavadi, A ; Ghasemzadeh, H ; Sharif University of Technology
    Rapra Technology Ltd  2006
    Abstract
    A novel superabsorbent composite system based on carboxymethyl cellulose (CMC) was prepared by graft copolymerization of acrylic acid (AA) in the presence of kaolin powder using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The effect of reaction variables, such as MBA, AA, and APS concentration and CMC/kaolin ratio on the water absorbency of the composite were studied. Evidence of grafting and kaolin interaction was obtained by comparing the FT-IR spectra of the initial substrates with that of the superabsorbent composite. The results indicated that with increasing amount of kaolin, the swelling capacity was increased and then... 

    Design, preparation, and characterization of silk fibroin/carboxymethyl cellulose wound dressing for skin tissue regeneration applications

    , Article Polymer Engineering and Science ; Volume 62, Issue 9 , 2022 , Pages 2741-2749 ; 00323888 (ISSN) Farshi, P ; Salarian, R ; Rabiee, M ; Alizadeh, S ; Gholipourmalekabadi, M ; Ahmadi, S ; Rabiee, N ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    Silk fibroin (SF) has been broadly applied in wound dressing fabrication because of its proper features for wound healing. In this work, we developed a carboxymethyl cellulose (CMC)/gelatin blend film with different concentrations of glycerol, and modified the optimized film with an SF layer through electrospinning process. Tensile strength and cell viability evaluation of blend films demonstrated that the glycerol content of 3% could be suitable as the substrate layer for the two-layer wound dressing. The morphology of the blend film and electrospun nanofibers was obtained from scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It concluded that... 

    Dyes Adsorption and Removal of Aqueous Solutions with Novel Adsorbents Based on Graphene Oxide

    , M.Sc. Thesis Sharif University of Technology Mohammadi, Esmaeel (Author) ; Borghei, Mahdi (Supervisor) ; Ghasemi, Shahnaz (Co-Supervisor)
    Abstract
    Nowadays, water pollution and water sources decreasion, is one of the important issues of our world. Treatment of polluted water and wastewater and recycling of those to industries and common uses, is very necessary. Dyes, is one of the biggest parts of water pollutants, especially, in textile plants. There are some ways for dye removal, in the industries; including biological, chemical and physical methods. Among of these methods, physical removal of dyes through adsorption (with Activated Carbon or other adsorbents), is very popular. Hydrogels are three-dimensional hydrophilic polymer networks, introducing very good swelling rate, mechanical properties and pollutants adsorption. In this... 

    Experimental Investigation of Surfactant Effects on Drop Formation of Shear-thinning Liquids

    , M.Sc. Thesis Sharif University of Technology Dastyar, Peyman (Author) ; Firoozabadi, Bahar (Supervisor) ; Afshin, Hossein (Supervisor)
    Abstract
    In this research, the characteristics of non-Newtonian, shear-thinning drop formation containing surfactant from a needle are investigated experimentally. The ambient fluid is air and all experiments have been conducted in a constant flow rate of drop phase fluid. Images of forming drop are taken using a high-speed camera and by processing them, important parameters in drop formation such as length of drop, minimum neck thickness, formation time and the size of satellite drops have been studied. Three non-Newtonian and three Newtonian fluids are considered in a way that the initial viscosity of non-Newtonian fluids would be equal to the viscosity of their corresponding Newtonian fluids.... 

    Enzyme Immobilization on Biopolymer Carrier by Microencapsulation Technique

    , M.Sc. Thesis Sharif University of Technology Hemmati, Mostafa (Author) ; Aalemzadeh, Iran (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
    Abstract
    β-galactosidase enzyme is immobilized from Kluyveromyces lactis by Microencapsulation method in various compositions of sodium alginate and Carboxymethyl cellulose. Optimum stabilization was gained at 1.85% sodium alginate, 0.9% carboxymethyl cellulose and 2% calcium chloride through applying Surface response methodology. Yield of immobilization and activity was 54.94% and 65.27%. variation of yield of immobilization versus alginate concentration was a quadratic curve with the maximum. When alginate's concentrations is low, the cavities diameter is great, so the enzyme leaks from capsule while immobilizing. At high concentrations of alginate, despite the smaller cavities, immobilization... 

    Designing Polymeric Biomaterials based on Polysaccharides with Tissue Adhesion and Hemostasis Performance

    , M.Sc. Thesis Sharif University of Technology Shokrani, Hanieh (Author) ; Mashayekhan, Shohreh (Supervisor) ; Kordzadeh, Azadeh (Co-Supervisor)
    Abstract
    Death can be the result of severe bleeding which is associated with the loss of a high amount of blood like what happens in accidents, wars, or operations. Classic methods to stop bleeding are mostly ineffective to decrease the hemostasis time and the volume of the lost blood. A wide variety of products like powders, foams, and hydrogels have been designed and synthesized either from natural or synthetic polymers. However, limitations like weak tissue adhesion, creating a moist environment in the wound site, infection, weak biodegradation, and hemolysis still have remained. Among the existing options to be used as hemostasis agents, polysaccharides can be appropriate considering their great... 

    Carboxymethyl cellulose-based functional film integrated with chitosan-based carbon quantum dots for active food packaging applications

    , Article Progress in Organic Coatings ; Volume 166 , 2022 ; 03009440 (ISSN) Riahi, Z ; Rhim, J. W ; Bagheri, R ; Pircheraghi, G ; Lotfali, E ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    A chitosan-based carbon quantum dots (CQDs) with multifunctional properties were synthesized using a hydrothermal process. The CQDs were spherical with an average size of 7.8 ± 2.4 nm. The CQD showed strong antioxidant activity, potent antibacterial activity against E. coli and L. monocytogenes, and antifungal activity against A. niger and P. chrysogenum. In addition, the prepared CQD showed negligible cytotoxicity against L929 cells even at a concentration of 500 μg/mL. Carboxymethyl cellulose (CMC)-based functional films were fabricated by adding various amounts of CQD. The CQDs were evenly dispersed in the polymer matrix to form a highly transparent UV-blocking film. The addition of CQD... 

    Study and Synthesis of Biocompatible Polymer and Loading of Peptide Drug for using in Drug Delivery

    , M.Sc. Thesis Sharif University of Technology Nikravesh, Niusha (Author) ; Vosoughi, Manouchehr (Supervisor) ; Alemzadeh, Iran (Co-Advisor)
    Abstract
    With the rapid development of biotechnology, peptide and protein drugs are now playing an increasingly important role in therapeutics. Compared with chemical drugs, peptide and protein drugs have some limitations such as low stability and rapid deactivation. Biodegradable and biocompatible polymeric micro carriers have been shown to have a high potential for the delivery of peptides and proteins. Among these polymers, alginate has been widely investigated as a biomaterial. Alginates are natural polysaccharide polymers isolated from brown seaweed. Bovine serum albumin (BSA) loaded calcium alginate microspheres produced in this study by a modified w/o emulsification method. The influence of... 

    Modified CMC. V. synthesis and super-swelling behavior of hydrolyzed CMC-g-PAN hydrogel

    , Article Journal of Applied Polymer Science ; Volume 103, Issue 2 , 2007 , Pages 877-883 ; 00218995 (ISSN) Pourjavadi, A ; Zohuriaan Mehr, M. J ; Ghasempoori, S. N ; Hossienzadeh, H ; Sharif University of Technology
    2007
    Abstract
    Polyacrylonitrile (PAN) was grafted onto carboxymethyl cellulose (CMC) sodium salt backbones by using cerie ammonium nitrate (CAN) as an initiator. The graft co-polymer, CMC-g-PAN, was hydrolyzed by NaOH solution to yield hydrogel, H-CMC-g-PAN. The nitrile groups of CMC-g-PAN were completely converted to a mixture of hydrophilic carboxamide and carboxylate groups during alkaline hydrolysis, followed by in situ crosslinking of the grafted PAN chains. The structure of the products was confirmed by FTIR spectroscopy. The synthetic parameters affecting the swelling capacity of the hydrogel (i.e., CMC-g-PAN add-on value, the hydrolysis time and temperature, and concentration of NaOH) were... 

    Magnetic carboxymethyl cellulose/silk fibroin hydrogel embedded with halloysite nanotubes as a biocompatible nanobiocomposite with hyperthermia application

    , Article Materials Chemistry and Physics ; Volume 287 , 2022 ; 02540584 (ISSN) Eivazzadeh Keihan, R ; Choopani, L ; Aghamirza Moghim Aliabadi, H ; Ganjali, F ; Kashtiaray, A ; Maleki, A ; Ahangari Cohan, R ; Salimi Bani, M ; Komijani, S ; Ahadian, M. M ; Salehpour, N ; Mahdavi, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    A novel and high potent magnetic nanobiocomposite was prepared based on Carboxymethyl cellulose (CMC) and epichlorohydrin (ECH) cross-linker interactions to form a three-dimensional cross-linked CMC hydrogel followed by silk fibroin (SF) and halloysite nanotubes (HNTs) modifications and further in situ Fe3O4 magnetic nanoparticles (MNPs) formation. Different analytical techniques like FT-IR, EDX, FE-SEM, XRD, TGA, and VSM were used to characterize the structure of the prepared nanobiocomposite. The spherical morphology of Fe3O4 MNPs and tubular HNTs were presented in the FE-SEM images. In biological tests, since the hemolysis percent was even less than the negative control, the CMC... 

    Fabrication and Enhancement of an Antibacterial Chitosancoated Allantoin-Loaded Skin Wound Dressing for Clinic Use

    , M.Sc. Thesis Sharif University of Technology Haki Zahi Margouk, Mohamamd (Author) ; Shamloo, Amir (Supervisor) ; Akbari, Javad (Supervisor)
    Abstract
    Skin as the largest organ of the body is constructed of three distinctive layers referred to as epidermis, dermis, and hypodermis. Epidermis is the outermost layer of the skin and acts as body’s first barrier against infectious agents and contains mostly sweat glands. Dermis is the mid-layer of the skin which makes up to 70% of the skin and plays a significant role in maintaining body’s metabolism and is home to a huge part of skin’s vascular network, nerve cells and hair follicles. Hypodermis on other hand, is the deepest layer of the skin and mainly acts as a bonding layer between upper skin layers and the soft tissue underneath. Although skin is proved to have a profound ability to... 

    Experimental investigation and comparison of Newtonian and non-Newtonian shear-thinning drop formation

    , Article Experimental Thermal and Fluid Science ; Volume 94 , 2018 , Pages 148-158 ; 08941777 (ISSN) Salehi, M. S ; Esfidani, M. T ; Afshin, H ; Firoozabadi, B ; Sharif University of Technology
    Elsevier Inc  2018
    Abstract
    The presence of small amount of polymer in Newtonian liquids affects the fluid behavior significantly and creates superficial differences between Newtonian and non-Newtonian drop formation. In the present study, Newtonian and non-Newtonian shear-thinning drop formation in air is examined experimentally and the geometrical parameters, such as drop elongation length, minimum neck diameter and current contact angle are studied for water, glycerin solutions (79, 89 and 94% w/w) and Carboxymethyl cellulose (CMC) solutions (0.5 to 1.5% w/w) drops. The results indicate that at initial stages of the drop growth, Newtonian and non-Newtonian liquids behave similarly. However, at the start of the... 

    Stability, size and optical properties of colloidal silver nanoparticles prepared by electrical arc discharge in water

    , Article EPJ Applied Physics ; Volume 48, Issue 1 , 2009 , Pages 10601p1-10601p7 ; 12860042 (ISSN) Ashkarran, A. A ; Iraji Zad, A ; Ahadian, M. M ; Hormozi Nezhad, M. R ; Sharif University of Technology
    2009
    Abstract
    We have fabricated and characterised colloidal silver nanoparticles by the electrical arc discharge method in DI water. Size and optical properties of the silver nanoparticles were studied versus different arc currents. Optical absorption indicates a plasmonic peak at 392 nm for 10 A which increases to 398 nm for 20 A arc current. This reveals that by raising the arc current the size of the nanoparticles increases. Optical absorption of silver nanoparticles after 3 weeks shows precipitation of them in a water medium. The effect of different surfactant and stabilizer concentrations such as cethyl trimethylammonium bromide (CTAB), polyvinyl pyrrolidone (PVP), sodium citrate, sodium dodecyl... 

    Applications of highly salt and highly temperature resistance terpolymer of acrylamide/styrene/maleic anhydride monomers as a rheological modifier: Rheological and corrosion protection properties studies

    , Article Journal of Molecular Liquids ; Volume 294 , 2019 ; 01677322 (ISSN) Ghaderi, S ; Ramezani Saadat Abadi, A ; Haddadi, A ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    Due to the weak performance of commercially affordable natural and synthetic polymeric thickeners in high temperatures and salinity, they fail to use in many applications especially in saline conditions with high temperatures. In this work, a new salt and temperature resistance acrylamide/styrene/maleic anhydride terpolymer (PASM-t) with self-associative properties was synthesized via a one-step inverse emulsion polymerization and its applicability as a rheological modifier and thickener was investigated. The characteristics of synthesized PASM-t (s-PASM-t) and its aqueous solutions were investigated using FT-IR, FE-SEM, GPC and rheometric mechanical spectrometry (RMS) analyses. The...