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Synthesis of Cationic Mesoporous Silica Nanoparticles as a Carrier for the Deliveryof Nucleic Acids
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Manouchehr (Supervisor) ; Arpanaei, Ayyoob (Supervisor) ; Javadi, Hamid Reza (Co-Advisor)
Abstract
Mesoporous silica nanoparticles (MSNP) have attracted lots of attentions because of their particular characteristics. Physical characteristics such as structure, morphology, porosity, and size of these nanoparticles have strong impact on their function and it can be conceived a wide range of applications for them by manipulating these characteristics. In this research, monodispersed MSNPs with a controllable size in the range of 50-130 nm and pore size in the range of 4-24 nm were synthesized and positively functionalized in order to develop a carrier for the delivery of nucleic acids (siRNA and pDNA). The MSNPs were synthesized by the template removing method.In this method, sodium...
Experimental Performance Analysis of Different Drill-in Fluids in Order to Reduce Formation Damage in Reservoir Sections
, M.Sc. Thesis Sharif University of Technology ; Goodarznia, Iraj (Supervisor)
Abstract
Formation damage is defined as any process that reduses the reservoir permeability relative to its normal state. Two major causes of this problem are filtrate and solid invasion into the pore spaces of reservoir rock.Therefore, the drilling fluid used for drilling the reservoir sections should prevent such a problem as much as possible.The goal of this study is to optimize the weighting additive particle size distribution to prevent permeability damage in one of the southern Iranian oil fields. By analizing the capillary pressure data of core samples, it seems that fracture presence in rock matrix leads to poor quality of mudcake, resulting peremabilty reduction in near wellbore region....
3D Bioprinting of oxygenated cell-laden gelatin methacryloyl constructs
, Article Advanced Healthcare Materials ; Volume 9, Issue 15 , 2020 ; Darabi, M. A ; Nasiri, R ; Sangabathuni, S ; Ertas, Y. N ; Alem, H ; Hosseini, V ; Shamloo, A ; Nasr, A. S ; Ahadian, S ; Dokmeci, M. R ; Khademhosseini, A ; Ashammakhi, N ; Sharif University of Technology
Wiley-VCH Verlag
2020
Abstract
Cell survival during the early stages of transplantation and before new blood vessels formation is a major challenge in translational applications of 3D bioprinted tissues. Supplementing oxygen (O2) to transplanted cells via an O2 generating source such as calcium peroxide (CPO) is an attractive approach to ensure cell viability. Calcium peroxide also produces calcium hydroxide that reduces the viscosity of bioinks, which is a limiting factor for bioprinting. Therefore, adapting this solution into 3D bioprinting is of significant importance. In this study, a gelatin methacryloyl (GelMA) bioink that is optimized in terms of pH and viscosity is developed. The improved rheological properties...
Preparation of biodegradable gelatin/PVA porous scaffolds for skin regeneration
, Article Artificial Cells, Nanomedicine and Biotechnology ; 2016 , Pages 1-8 ; 21691401 (ISSN) ; Dadbin, S ; Frounchi, M ; Rajabi, S ; Sharif University of Technology
Taylor and Francis Ltd
2016
Abstract
Porous scaffolds composed of gelatin/poly (vinyl alcohol), (Gel/PVA), were prepared using combination of freeze gelation and freeze drying methods. The effect of polymer concentration, gelatin/PVA ratio, and glutaraldehyde/gelatin ratio (GA/Gel) was investigated on morphology of pores, swelling ratio, biodegradation, and skin cell culture. At optimum preparation conditions the scaffolds had uniform pore size distributions showing high swelling ratio of 23.6. The scaffolds were of biodegradable nature and almost degraded in 28 days. Human dermal fibroblast cells (HDF) were cultured on the scaffolds and MTS assay was conducted to evaluate the influence of PVA on growth and proliferation of the...
Preparation of biodegradable gelatin/PVA porous scaffolds for skin regeneration
, Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 45, Issue 5 , 2017 , Pages 928-935 ; 21691401 (ISSN) ; Dadbin, S ; Frounchi, M ; Rajabi, S ; Sharif University of Technology
Taylor and Francis Ltd
2017
Abstract
Porous scaffolds composed of gelatin/poly (vinyl alcohol), (Gel/PVA), were prepared using combination of freeze gelation and freeze drying methods. The effect of polymer concentration, gelatin/PVA ratio, and glutaraldehyde/gelatin ratio (GA/Gel) was investigated on morphology of pores, swelling ratio, biodegradation, and skin cell culture. At optimum preparation conditions the scaffolds had uniform pore size distributions showing high swelling ratio of 23.6. The scaffolds were of biodegradable nature and almost degraded in 28 days. Human dermal fibroblast cells (HDF) were cultured on the scaffolds and MTS assay was conducted to evaluate the influence of PVA on growth and proliferation of the...
Design and fabrication of injectable microcarriers composed of acellular cartilage matrix and chitosan
, Article Journal of Biomaterials Science, Polymer Edition ; Volume 29, Issue 6 , 2018 , Pages 683-700 ; 09205063 (ISSN) ; Mashayekhan, S ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
Cartilage is an avascular tissue with limited self-repair ability. Since the methods for treatment of cartilage defects have not been effective, new therapies based on tissue engineering are considered over the recent years. In this study, human cartilage tissue was decellularized and porous injectable microcarriers (MCs) composed of acellular extracellular matrix (ECM) of cartilage tissue and chitosan (CS), with different ECM weight ratios, were fabricated by electrospraying technique to be used in the treatment of articular cartilage defects. Various properties of ECM/CS MCs such as microstructure, mechanical strength, water uptake behaviour, and biodegradability rate were investigated....
High flux electrospun nanofiberous membrane: Preparation by statistical approach, characterization, and microfiltration assessment
, Article Journal of the Taiwan Institute of Chemical Engineers ; Volume 59 , 2016 , Pages 474-483 ; 18761070 (ISSN) ; Mousavi, S. A ; Bastani, D ; Sharif University of Technology
Taiwan Institute of Chemical Engineers
Abstract
Preparation, characterization and evaluation of new generation of micro-filters based on polyacrylonitrile electrospun nanofiberous membrane (ENM) were thoroughly investigated. First, quantitative relationships between average diameter, bead area density of nano-fibers and certain electrospinning parameters, i.e., concentration, voltage, spinning distance, and feed rate, were established by empirical modeling based on a central composite design. The analysis revealed that concentration, voltage and distance are the significant parameters. Also, adequacy checking indicated the appropriateness of fit for the models. Afterwards, bead-free ENMs with diameter of 100-500 nm were prepared and...
PLGA/TiO2 nanocomposite scaffolds for biomedical applications: Fabrication, photocatalytic, and antibacterial properties
, Article BioImpacts ; Volume 11, Issue 1 , 2021 , Pages 45-52 ; 22285652 (ISSN) ; Madaah Hosseini, H. R ; Nokhbedehghan, Z ; Samadikuchaksaraei, A ; Sharif University of Technology
Tabriz University of Medical Sciences
2021
Abstract
Introduction: Porous 3D scaffolds synthesized using biocompatible and biodegradable materials could provide suitable microenvironment and mechanical support for optimal cell growth and function. The effect of the scaffold porosity on the mechanical properties, as well as the TiO2 nanoparticles addition on the bioactivity, antimicrobial, photocatalytic, and cytotoxicity properties of scaffolds were investigated. Methods: In the present study, porous scaffolds consisting poly (lactide-co-glycolide) (PLGA) containing TiO2 nanoparticles were fabricated via air-liquid foaming technique, which is a novel method and has more advantages due to not using additives for nucleation compared to former...
A cellular cardiac matrix-based porous microcarrier as a cell delivery system in myocardial tissue engineering application
, Article Iranian Polymer Journal (English Edition) ; Volume 31, Issue 9 , 2022 , Pages 1079-1091 ; 10261265 (ISSN) ; Mashayekhan, S ; Khanmohammadi, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Myocardial infarction (MI) causes a high mortality rate in the world every year. Myocardial tissue engineering using extracellular matrix-derived substrate and cytocompatible biopolymers is a promising approach for treating MI. Besides, injectable porous microspheres are developing engineer constructs to use as dual-purpose microcarriers for cell culture and injectable scaffolds in trivial invasiveness for tissue implantation. This study aimed to fabricate porous microcarriers composed of myocardial extracellular matrix and chitosan using an electrospraying technique. The effect of electrospraying parameters, including extracellular matrix/chitosan ratio and voltage, on MCs diameter was...
Development of block copolymer-templated crack-free mesoporous anatase-TiO2 film: tailoring sol–gel and EISA processing parameters and photovoltaic characteristics
, Article Journal of Materials Science: Materials in Electronics ; Volume 26, Issue 3 , March , 2015 , Pages 1543-1553 ; 09574522 (ISSN) ; Mohammadi, M. R ; Faghihi Sani, M. A ; Sharif University of Technology
Springer New York LLC
2015
Abstract
A new facile strategy for preparation of mesoporous anatase-TiO2 films by a combination of sol–gel and evaporation-induced self-assembly (EISA) processes aided by tri-block Pluronic F127 is reported. Two major parameters, sol preparation and EISA processing parameters, are identified for preparation of mesoporous crack-free films with desired thickness. The mesoporous crack-free films with thickness of 650 nm can be obtained with low water: precursor molar ratio (e.g., 2.5:1) under aging in 10 % relative humidity for 72 h at the low temperature of 5 °C. Although template: precursor molar ratio and annealing temperature show little influence on preparation of crack-free films the optimum...
Surface modification of polysulfone ultrafiltration membranes by free radical graft polymerization of acrylic acid using response surface methodology
, Article Journal of Polymer Research ; Volume 26, Issue 9 , 2019 ; 10229760 (ISSN) ; Asadollahi, M ; Mousavi, S. A ; Bastani, D ; Aghaeifard, F ; Sharif University of Technology
Springer Netherlands
2019
Abstract
In this research, polysulfone (PSf) ultrafiltration (UF) membranes were prepared by a phase inversion method. Surface modification of the PSf membranes was carried out via grafting of acrylic acid as a hydrophilic monomer by free radical graft polymerization initiated by redox reaction. A central composite design (CCD) of response surface methodology (RSM) was applied to design the experiments. The process variables were acrylic acid concentration (CAA), redox system contact time (T1), and acrylic acid polymerization time (T2), while the contact angle (CA), pure water flux (PWF), and flux recovery ratio (FRR) were considered as the responses. Analysis of variance (ANOVA) demonstrated that...
Integrated image processing and computational techniques to characterize formation damage
, Article SPE International Conference and Exhibition on Formation Damage Control 2018, 7 February 2018 through 9 February 2018 ; Volume 2018-February , 2018 ; Rabbani, A ; Salehi, S ; Ghalambor, A ; Sharif University of Technology
Society of Petroleum Engineers (SPE)
2018
Abstract
Filtrate and solid invasion from drilling fluids are two key sources of formation damage, and can result in formation permeability impairment. Typically, spurt invasion of mud solids causes the evolution of an external mud cake which tends to reduce further solids and filtrate influx. However, uncontrolled spurt and filtrate invasion are detrimental because they reduce the permeability of the formation. Mud composition, formation rock's permeability and porosity, and temperature can influence both spurt and filtrate invasion. The sizes of mud solids relative to the average pore size of a rock are also important in predicting the extent of mud invasion and permeability impairment. In this...
Statistical model of dispersion in a 2-D glass micromodel
, Article 16th SPE/DOE Improved Oil Recovery Symposium 2008 - ""IOR: Now More Than Ever."", Tulsa, OK, 19 April 2008 through 23 April 2008 ; Volume 2 , 2008 , Pages 527-539 ; 9781605601656 (ISBN) ; Kharrat, R ; Rashtchian, D ; Vossoughi, S ; Sharif University of Technology
Society of Petroleum Engineers (SPE)
2008
Abstract
Microscopic Visualization of the porous media can provide valuable information to enhance understanding of pore-scale transport phenomena. Here, a micromodel which its grains and pores are non-uniform in size, shape and distribution is considered as porous medium. The pore size distribution as well as pore length distribution was extracted by applying an image analysis technique. A two-dimensional random network model of the micromodel has been constructed which the nonuniformity is considered by assigning measured distribution functions. The random particle method was applied for correlating and predicting dispersion coefficients based on probabilistic approaches. Statistical derivations...
Photocatalytic activity of mesoporous microbricks of ZnO nanoparticles prepared by the thermal decomposition of bis(2-aminonicotinato) zinc (II)
, Article Cuihua Xuebao/Chinese Journal of Catalysis ; Volume 36, Issue 5 , May , 2015 , Pages 742-749 ; 02539837 (ISSN) ; Tadjarodi, A ; Akhavan, O ; Sharif University of Technology
Science Press
2015
Abstract
Hollow microblocks of [Zn(anic)2 ], as a novel coordination compound, were synthesized using 2-aminonicotinic acid (Hanic) and zinc (II) nitrate tetrahydrate. The chemical composition of the zinc complex, ZnC12 H10 N4 O4 , was determined by Fourier transform infrared (FTIR) spectroscopy and elemental analysis. The synthesized zinc complex was used as a precursor to produce ZnO nanostructures by calcination at 550 °C for 4 h. Morphological studies by scanning electron microscopy and transmission electron microscopy revealed the formation of porous microbricks of ZnO nanoparticles. N2 adsorption-desorption analysis showed that the...
Performance of a nickel-alumina catalytic layer for simultaneous production and purification of hydrogen in a tubular membrane reactor
, Article RSC Advances ; Volume 6, Issue 79 , 2016 , Pages 75686-75692 ; 20462069 (ISSN) ; Towfighi, J ; Zamaniyan, A ; Ganji Babakhani, E ; Heidari, M ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
A catalytic membrane reactor was synthesized by coating a 4-5 micron thick Ni/γ-Al2O3 layer on top of a hydrogen selective SiO2/Al2O3 composite membrane using a sol-gel method. Mercury intrusion and BET analysis indicated a uniform size distribution with an average pore size of 285 nm and average surface area of 279 m2 g-1. Single-component permeation tests were carried out for H2, CH4 and CO2 in the temperature range of 650-800 °C and the results showed the same permeance and selectivity values for hydrogen as the composite membrane without a catalytic layer. Performance of the catalytic membrane was evaluated by using as a membrane reactor for the methane steam reforming reaction with a...
Light olefin production on the Co-Ni catalyst: Calcination conditions, and modeling and optimization of the process conditions by a statistical method
, Article New Journal of Chemistry ; Volume 44, Issue 18 , 2020 , Pages 7467-7483 ; Akbari, M ; Mirzaei, N ; Abdouss, M ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
The present work is comprised of two main parts. In part 1 the Co-Ni/γ-Al2O3 catalyst was prepared using a sol-gel procedure. Then the effect of calcination variables including the calcination temperature and time on the catalytic performance for production of light olefins was investigated and optimized. The obtained results have shown that the catalyst which was calcined at 550 °C for 6 h has revealed the better catalytic performance for production of light olefins. In part 2 the effect of process conditions including the reaction temperature, H2/CO feed ratio and total reaction pressure on the catalytic performance (CO conversion%, (C2-C4) selectivity% and C5+ selectivity%) was...
A single layer deposition of Li-doped mesoporous TiO2beads for low-cost and efficient dye-sensitized solar cells
, Article New Journal of Chemistry ; Volume 45, Issue 5 , 2021 , Pages 2470-2477 ; 11440546 (ISSN) ; Nouri, E ; Mohsenzadegan, N ; Mohammadi, M. R ; Martinez Chapa, S. O ; Sharif University of Technology
Royal Society of Chemistry
2021
Abstract
Herein, we report a new strategy for improving the efficiency and reducing the fabrication cost of dye-sensitized solar cells (DSCs) by elimination of the three- or four-fold layer deposition of TiO2. This is performed by replacing a single layer deposition of mesoporous TiO2 beads, with sub-micrometer size, high surface area and tunable pore size, synthesized by a combination of sol-gel and solvothermal methods. Furthermore, superior electronic properties gained by a reduction in electronic trap states are achieved through doping of pristine TiO2 beads with lithium. The beads have a spherical shape with monodispersed texture consisting of anatase-TiO2 nanocrystals and ultra-fine pores. The...
Extraction of hydroxyapatite nanostructures from marine wastes for the fabrication of biopolymer-based porous scaffolds
, Article Marine Drugs ; Volume 18, Issue 1 , 2020 ; Mohandes, F ; Mazaheri, M ; Dolatyar, B ; Askari, M ; Simchi, A ; Sharif University of Technology
MDPI AG
2020
Abstract
Three-dimensional porous nanocomposites consisting of gelatin-carboxymethylcellulose (CMC) cross-linked by carboxylic acids biopolymers and monophasic hydroxyapatite (HA) nanostructures were fabricated by lyophilization, for soft-bone-tissue engineering. The bioactive ceramic nanostructures were prepared by a novel wet-chemical and low-temperature procedure from marine wastes containing calcium carbonates. The effect of surface-active molecules, including sodium dodecyl sulfate (SDS) and hexadecyltrimethylammonium bromide (CTAB), on the morphology of HA nanostructures is shown. It is demonstrated that highly bioactive and monophasic HA nanorods with an aspect ratio > 10 can be synthesized in...
Mechanism understanding of Li-ion separation using a perovskite-based membrane
, Article Membranes ; Volume 12, Issue 11 , 2022 ; 20770375 (ISSN) ; Habibi, M ; Rezvantalab, S ; Mehdizadeh Chellehbari, Y ; Maleki, R ; Razmjou, A ; Sharif University of Technology
MDPI
2022
Abstract
Lithium ions play a crucial role in the energy storage industry. Finding suitable lithium-ion-conductive membranes is one of the important issues of energy storage studies. Hence, a perovskite-based membrane, Lithium Lanthanum Titanate (LLTO), was innovatively implemented in the presence and absence of solvents to precisely understand the mechanism of lithium ion separation. The ion-selective membrane’s mechanism and the perovskite-based membrane’s efficiency were investigated using Molecular Dynamic (MD) simulation. The results specified that the change in the ambient condition, pH, and temperature led to a shift in LLTO pore sizes. Based on the results, pH plays an undeniable role in...
Nanoporous composites of activated carbon-metal organic frameworks for organic dye adsorption: Synthesis, adsorption mechanism and kinetics studies
, Article Journal of Industrial and Engineering Chemistry ; Volume 81 , 2020 , Pages 405-414 ; Simchi, A ; Shahriyari Far, H ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2020
Abstract
Activated carbon (AC) is an inert adsorbent material that has widely been used in water treatment or removing of environmental pollutants from water. In order to improve the adsorption of AC, which highly depends on its pore size and surface area, we prepared highly porous adsorbent composites of activated carbon (AC)/chromium-based MOF (MIL-101(Cr)). The composite has a high specific surface area of 2440 m2 g−1 and total pore volume of 1.27 cm3 g−1. To show the efficiency of the composite as an adsorbent, the removal kinetics of anionic dyes (Direct Red 31 and Acid Blue 92) from aqueous solutions dependent on the amount of composite, adsorption time, concentration of dye and pH is...