Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Study of Mesoporous Silica Nanoparticles as Nanocarriers for Sustained Release of Curcumin 139 146 14567 EN A. Bolouki Chemical Engineering Department, Islamic Azad University Shahrood Branch, Shahrood, I. R. Iran L. Rashidi Food and Agriculture Department, Standard Research Institute, Iranian National Standards Organization, I. R. Iran E. Vasheghani-Farahani Biotechnology Division, Chemical Engineering Department, Tarbiat Modares University, Tehran, I. R. Iran. Z. Piravi-Vanak Food and Agriculture Department, Standard Research Institute, Iranian National Standards Organization, I. R. Iran Journal Article 2015 02 20 Curcumin (CUR) is a hydrophobic molecule and beneficial antioxidant with known anticancer property. The bioavailability of curcumin is low because of its hydrophobic structure. Mesoporous silica nanoparticles (MSN) loaded by CUR were used as nanocarriers for sustained release of CUR in four different media such as simulated gastric,intestinal, colon and body fluids (SGF, SIF, SCF, and SBF, respectively). In this study MSN and its amine-functionalized (AP-MSN) were synthesized, loaded by CUR and then characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), N2 adsorption isotherms, X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). TGA showed that the amount of CUR loaded into MSN and AP-MSN (named MSN-CUR, AP-MSN-CUR, respectively) was 1.44 and 9.5%, respectively. Entrapment efficiency of CUR in MSN and AP-MSN was found to be 3.6 and 23.75%, respectively. Release rate of CUR from AP-MSN-CUR was slower than that from MSN-CUR at different pHs of media. In addition, the release rate of CUR from AP-MSN-CUR in acidic buffer solution was slower than that in alkaline media.

https://www.ijnnonline.net/article_14567_1589515970487c94597dab5c1be44085.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Study of Super Capacitive Behavior of Polyaniline/manganese Oxide-Carbon Black Nanocomposites Based Electrodes 147 157 14568 EN M.G. Hosseini Electrochemistry Research Laboratory, Department of Physical Chemistry, Chemistry Faculty, University of Tabriz, Tabriz, I. R. Iran E. Shahryari Electrochemistry Research Laboratory, Department of Physical Chemistry, Chemistry Faculty, University of Tabriz, Tabriz, I. R. Iran R. Najjar Electrochemistry Research Laboratory, Department of Physical Chemistry, Chemistry Faculty, University of Tabriz, Tabriz, I. R. Iran I. Ahadzadeh Department of organic Chemistry, University of Tabriz, Tabriz, I. R. Iran. Journal Article 2014 06 26 The supercapacitive behavior of polyaniline/MnO2-carbon black (PANI/MnO2-CB), MnO2-CB nanocompositesand CB was studied. MnO2-CB made by the in situ direct coating method to deposit MnO2 onto CB; then PANI coating was coated on it. Morphology of the nanocomposite was studied by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The electrochemical properties of electrodes were investigated by cyclic voltammetry (CV), galvanostatic charge–discharge and electrochemical impedance spectroscopy (EIS) techniques in 0.5 M Na2SO4. The specific capacitance of 179.8 F. g-1 was obtained for PANI/MnO2-CB compared with 121 F. g-1 for MnO2-CB and 44.87 F. g-1 for CB. The EIS results also revealed improved capacitive properties of CB by the addition of MnO2 and PANI.

https://www.ijnnonline.net/article_14568_77004ef63f2ef7dab481a16152f60c43.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Analytical Solution for the Forced Vibrations of a Nano-Resonator with Cubic Nonlinearities Using Homotopy Analysis Method 159 166 14569 EN E. Maani Miandoab School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, I. R. Iran F. Tajaddodianfar School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, I. R. Iran H. Nejat Pishkenari Mechanical Engineering Department, Sharif University of Technology, Tehran, I. R. Iran. H. M. Ouakad Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, 31261, Dhahran, Kingdom of Saudi Arabia, Saudi Arabia Journal Article 2014 12 25 Many of nonlinear systems in the field of engineering such as nano-resonator and atomic force microscope can be modeled based on Duffing equation. Analytical frequency response of this system helps us analyze different interesting nonlinear behaviors appearing in its response due to its rich dynamics. In this paper, the general form of Duffing equation with cubic nonlinearity as well as parametric excitations is considered and its frequency response is derived utilizing Homotopy Analysis Method (HAM) for the first time. Although time response of different Duffing systems has been analyzed using HAM, derivation of its frequency response equation by applying this powerful method has not been presented. The main advantage of proposed simple closed-form solution is that it is not restricted to weakly nonlinear systems in contrast with perturbation methods. Because of numerous applications of Micro-electro-mechanical resonator and its rich and nonlinear dynamics, it is considered as a case study in this paper and the obtained analytical equation is applied to find its frequency response. The validation of analytical method is verified by comparing the results with numerical simulations. It is also shown that proposed closed-form equation for nano-resonator frequency response can capture both hardening and softening behavior of nano-resonator as well as jump phenomenon. The results of this paper can be useful in analysis of different engineering systems modeled by general Duffing equation.

https://www.ijnnonline.net/article_14569_7d7b04e989115e193107af57ad662dd2.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Surface Modification of Mesoporous Nanosilica with [3-(2-Aminoethylamino) propyl] Trimethoxysilane and Its Application in Drug Delivery 167 177 14570 EN Z. Mohamadnia Department of chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Gava zang, Zanjan, I. R. Iran E. Ahmadi Department of chemistry, University of Zanjan, Zanjan, I. R. Iran. M. Ghasemnejad Department of chemistry, University of Zanjan, Zanjan, I. R. Iran. S. Hashemikia Department of Textile Engineering, Center of Excellence in Textile, Amirkabir University of Technology (Tehran Polytechnic), Tehran, I. R. Iran. A. Doustgani Department of chemistry, University of Zanjan, Zanjan, I. R. Iran., Department of Chemical Engineering, University of Zanjan, Zanjan, Iran Journal Article 2015 04 13 Mesoporous silica nanoparticles with unique structure (SBA-15) were synthesized and modified by [3-(2-Aminoethylamino) propyl] trimethoxysilane (AEAPTMS). The synthesized nanoparticles were characterized by TGA, N‌2‌ adsorption, SEM, FTIR, CHN elemental analysis. The total weight loss for the modified SBA-15 is 15.2% and thermal analysis revealed that 1.5 mmol AEAPTMS/1g SBA-15 had been grafted. The modified particles were used as a drug delivery system. Ibuprofen as common nonsteroidal anti-inflammatory drugs was used to evaluate the controlled drug release properties of modified SBA-15.The results show that the modification of SBA-15 with organic groups such as [3-(2-Aminoethylamino) propyl] trimethoxysilane and (3-aminopropyl) triethoxysilane (APTES) improve the organophilicity of the SBA-15 and the drug loading efficiency. The results of drug delivery experiments reveal that the surface modification of SBA-15 with amino groups significantly decreases the drug delivery rate. The data obtained from the in vitro release studies was used to evaluate the kinetic mechanism of release; the initial 60% release of drug at pH 7.4 fits with the Korsmeyer – Peppas model, when diffusion is the main drug release mechanism.

https://www.ijnnonline.net/article_14570_8b5578656a9a3c888090fb81c2869c63.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Nanobiomechanical Properties of Microtubules 179 184 14571 EN M. Motamedi Department of Mechanical Engineering, University of Tehran, Tehran, I. R. Iran. M. Mosavi Mashhadi Department of Mechanical Engineering, University of Tehran, Tehran, I. R. Iran. Journal Article 2015 04 10 Microtubules, the active filaments with tubular shapes, play important roles in a wide range of cellular functions, including structural supports, mitosis, cytokinesis, and vesicular transport, which are essential for the growth and division of eukaryotic cells. Finding properties of microtubules is one of the main concerns of scientists. This work helps to obtain mechanical properties of microtubule. For this aim, interaction energy in alpha-beta, beta-alpha, alpha-alpha and beta-beta dimers was calculated using the molecular dynamic simulation and GROMACS software package. Force-distance diagrams for these dimers were obtained using the relation between potential energy and force. Each dimer has nearly 8500 atoms. There are more than 100 tubulins in a microtubule with 13 protofilaments and 0.1 µm length. So, molecular dynamic simulation of a microtubule will be a very difficult task. Then, it would be better to build a structural mechanic model which has rather similar properties with microtubule. The first and most important step for this process is to obtain the interaction force between tubulins. Therefore, instead of the each tubulin we can consider one sphere with 55 kDa weights that connect to another tubulin with a nonlinear connection such as nonlinear spring. The mechanical model of microtubule was used to calculate Young’s modulus based on finite element method. The Young’s modulus has good agreement with previous works.

https://www.ijnnonline.net/article_14571_6dc4166c5aa3123f245a786381d0eb9c.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Investigation in to Properties of Polyurethane Closed Cell by High Loading of SiO2 Nanoparticles 185 192 14572 EN M. Nadafan Department of Physics, Tarbiat Modares University, Tehran, I. R. Iran. R. Malekfar Department of Physics, Tarbiat Modares University, Tehran, I. R. Iran. Z. Dehghani Department of Physics, Faculty of Basic Sciences, University of Neyshabur, Neyshabur, I. R. Iran Journal Article 2014 07 08 In this research the composition of polyurethane closed cell (PUCC) with two different concentrations of SiO2 nanoparticles (1.0 and 2.0 wt%) have been prepared. Optical microscopy and SEM imaging, watering uptake, FTIR and Raman spectroscopy of the synthesized samples were carried out. The optical microscopy imaging of samples showed differences in the appearance of matrix produced by applying different concentrations of SiO2 nanoparticles (NPs). The mean cell size of the foams decreased with the addition of SiO2 NPs from 0.0 wt% up to 2.0wt%.Variation in the water uptake of specimens is related to the function of SiO2NPs concentrations. The degree of phase separation and the hydrogen bonding index in samples were evaluated in terms of their FTIR spectroscopy data. The apparent and real densities of foams were measured and then total, open and closed porosity of samples were calculated. With elevating the amount of nanoparticles the open porosity of samples almost increased, while the closed and total porosity decreased. The Raman spectra of the synthesized samples were used for evaluating possible interaction between SiO2 NPs and PUCC foams.

https://www.ijnnonline.net/article_14572_fcc852ebf6cd4e2633e85d81cc3cab92.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 An Experimental Study on Toughening Mechanisms of Fillers in Epoxy/ Silica Nanocomposites 193 199 14573 EN M. Shariati Department of Mechanics, Engineering Faculty, Ferdowsi University of Mashhad, Mashhad, I. R. Iran G. A. Farzi Department of Material and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar, I. R. Iran. A. Dadrasi Department of Mechanical Engineering, Shahrood University, Shahrood, I. R. Iran. M. Amiri Department of Material and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar, I. R. Iran. R. Rashidi Meybodi Department of Mechanical Engineering, Payame Noor University, Tehran, I. R. Iran. Nano Structured Coatings Institute of Yazd Payame Noor University, Yazd, I. R. Iran Journal Article 2013 03 14 In this paper, a systematic study on the effects of particle size and hybrid of two different size of silica nanoparticles on the toughening mechanisms of bisphenol-A epoxy was conducted. Nanosilica particles with mean diameter of 17 nm and 65 nm were blended into epoxy system. Probable synergy effects of these two nanoparticles on Young’s modulus and yield strength have been investigated. Results showed that the addition of the silica nanoparticles and also increasing content of nanoparticles improved Young’s modulus in all composites. In addition, the particle size did not show a considerable effect on the Young’s modulus and the use of both types of particles in a composite showed negligible synergy effect. On the other hands, results revealed that the addition of these nanoparticles did not change the yield stress of composites significantly. The fracture surfaces of composites were studied by Scanning electron microscopy. It was revealed that in all three series of nanocomposites, crack deflection, crack forking and debonding were the most important mechanisms.

https://www.ijnnonline.net/article_14573_52479f411a0a7366220da0cc45559bd0.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Improvement of Thermal Stability of Polyacryl amide Solution Used as a Nano-fluid in Enhanced Oil Recovery process by Nanoclay 201 208 14576 EN G. Cheraghian Young Researchers and Elite Club, Omidieh Branch, Islamic Azad University, Omidieh, I. R. Iran S. Sh. Khalili Nezhad Young Researchers and Elite Club, Quchan Branch, Islamic Azad University, Quchan, I. R. Iran S. Bazgir Department of Polymer Engineering, Science and Research Branch, Islamic Azad University, Tehran, I. R. Iran Journal Article 2014 01 17 Research in nanotechnology in the petroleum industry is advancing rapidly and an enormous progress in the application of nanotechnology in this area is to be expected. In particular, adding nanoparticles to fluids may drastically benefit enhanced oil recovery and improve well drilling, by changing the properties of the fluid, rocks wettability alteration, advanced drag reduction, strengthening the sand consolidation, reducing the interfacial tension and increasing the mobility of the capillary trapped oil. In this study, we focus on roles of clay nano-particles on viscosity of polymer, temperature and salinity of polymer solutions different nanoparticles. The viscosity of these polymer solutions was measured using a rheometer and in each measurement, the shear rate was changed, and the effect of this change on the viscosity was measured. Results showed that increasing temperature on the viscosity of solution plays a positive role when the dispersed clay nanoparticles are present in the solution.

https://www.ijnnonline.net/article_14576_7ce7fe98a64dd1ef509fedb677fcea5a.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Specific Fast Response CH4 Gas Sensor Based on Metal Oxide, Tungsten Carbide /SnO2Core-Shell Modified Interdigitated Electrode 209 217 14581 EN S. Nikmanesh School of Electrical and Computer engineering, Shiraz University, I. R. Iran M.M. Doroodmand Department of Chemistry, College of Sciences, Shiraz University, I. R. Iran M.H. Sheikhi School of Electrical and Computer engineering, Shiraz University, I. R. Iran Journal Article 2013 05 28 In this study, a specific CH4 sensor is fabricated based on interdigitated electrode that modified with core-shell of tungsten carbide/tin oxide (WC/SnO2) nanoparticles by wet chemical method in different percents of carbon and tungsten. The morphology of wet chemical-synthesized WC/SnO2 core-shell was evaluated by different methods such as patterned X-ray diffraction (XRD), and particle size analyzer (PSA). The fabricated sensor is selected as specific nanomaterial for CH4 detection. In the fabricated CH4 sensor, change in resistance of the sensor was considered as the detection system. In this study, figures of merits such as linearity, specificity, response time were also evaluated. No serious interference was evaluated for different foreign gases, introduced to a certain concentration of CH4. The reliability of the fabricated CH4 sensor was evaluated via measuring CH4 in several gaseous samples. A fast response time about 8s and recovery time 11s has obtained from (5.0% WC-doped SnO2).

https://www.ijnnonline.net/article_14581_72cc4c5e6cbde70aa374bf94076ad722.pdf

Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 11 3 2015 09 01 Effect of Acid Treatment of Carbon Nanotubes on Their Adsorption Capacities of Benzene and Toluene 219 224 14582 EN F. Pourfayaz Department of Renewable Energies and Environment, Faculty of New Sciences and Technologies, University of Tehran, Tehran, I. R. Iran S. Iranpour Chemical Processes Design Research Group, ACECR, Faculty of engineering, University of Tehran, Tehran, I. R. Iran. O. Shojaei Chemical Processes Design Research Group, ACECR, Faculty of engineering, University of Tehran, Tehran, I. R. Iran. Journal Article 2015 03 20 Toluene and benzene were eliminated using multi-walled carbon nanotubes (MWCNTs). In order to investigate influence of acid treatment on the MWCNTs adsorption capacities, the MWCNTs were functionalized by nitric acid (10 M) under reflux conditions for 2 h. Fourier transform infrared (FTIR) and Raman spectroscopy were employed to confirm the formation of functional groups on the nanotubes surface. Specific surface areas of the nanotubes were also measured using the Brunauer–Emmett–Teller (BET) method. Adsorption capacities of the functionalized and unfunctionalized MWCNTs were obtained and then compared with each other. FTIR and Raman spectra proved the formation of functional groups on the MWCNTs surface as a result of this acid treatment. Adsorption capacities measurements revealed that the functionalized MWCNTs have large adsorption capacities of toluene and benzene as compared with the unfunctionalized MWCNTs. This enhancement of adsorption capacities was ascribed to an increase in the specific surface area of the nanotubes due to this acid treatment.

https://www.ijnnonline.net/article_14582_ab51d7a8e04f1b4c88439526b107c768.pdf