Effects of protective agents (PVA & PVP) on the formation of silver nanoparticles
B.
Sadeghi
Department of Chemistry, Faculty of science, Islamic Azad University, Tonekabon Branch, Tonekabon, I. R. Iran
author
M. A. S.
Sadjadi
Department of Chemistry, Faculty of science, Islamic Azad University, Science and research branch, Hessarak, Tehran, I. R. Iran
author
A.
Pourahmad
Department of Chemistry, Faculty of science, Islamic Azad University, Rasht Branch, Rasht, I. R. Iran
author
text
article
2008
eng
In this study silver/poly vinyl alcohol (PVA) and silver/poly vinyl pyrrolidone (PVP) Nanocomposites were prepared via reduction of silver salt by employing DMF (N, N`- dimethyl formamide) as a reducing agent. Effects of protective agents such as PVA and PVP were also described here. We show that the acidic pH of PVP solution also affects the interaction between protective agents and silver nanoparticles. The nanoparticles were characterized by ultra violet-visible spectroscopy (UV-vis), FTIR spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). From the figures, it can be concluded that PVP is somewhat better than PVA for preventing silver nanoparticles from their agglomeration.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
3
12
https://www.ijnnonline.net/article_3992_4c5e4e724ca63a625bde06a711bbb401.pdf
Preparation and proposed mechanism of ZnO Nanostructure Thin Film on Glass with Highest c-axis Orientation
M. H.
Habibi
Catalysis Division, Department of Chemistry, University of Isfahan, Isfahan,
author
M.
Khaledi Sardashti
Catalysis Division, Department of Chemistry, University of Isfahan, Isfahan
author
text
article
2008
eng
In this paper, ZnO thin film is deposited on slide glass substrate using the sol-gel process. Presenting well-defined orientation of ZnO thin films Nanostructure were obtained by dip coating of zinc acetate dihydrate, monoethanolamine (MEA), de-ionized water and isopropanol alcohol. The annealed ZnO thin films were transparent ca 85-90% in visible range with an absorption edges at about 375 nm. The morphologies and phase structure show that the ZnO/glass film is formed by a layer of ZnO nano-sized particles with average diameter of 40 nm. X-ray diffraction results showed polycrystalline wurtzite with a highest c-axis preferential (002) orientation with the only sharp X-ray diffraction peak at 34.40 corresponding to the hexagonal ZnO. The high c-axis orientation improved and the grain size increased by the annealing temperature. These results showed that the sol-gel deposited ZnO films have potential applications such as catalyst and transparent electrodes in optic and electronic devices.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
13
16
https://www.ijnnonline.net/article_3993_67abb8a51ecbea4426a802b76a979f83.pdf
Yeast Mediated Synthesis of Silver Nanoparticles
Anal K.
Jha
University Department of Chemistry, T.M. Bhagalpur University, Bhagalpur 812007, India
author
K.
Prasad
University Department of Physics, T.M. Bhagalpur University, Bhagalpur 812007, India
author
and A. R.
Kulkarni
Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology, Mumbai 400 076, India
author
text
article
2008
eng
A green low-cost and reproducible yeast mediated synthesis of silver nanoparticles is reported. The synthesis is performed at room temperature. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of Ag nanoparticles. Nanoparticles almost spherical in shape having a size of 6-20 nm are found.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
17
22
https://www.ijnnonline.net/article_3994_200cfd3f0f00dc6936b2be2cc53ef3f6.pdf
Fabrication and evaluation of gelatin nanoparticles for delivering of anti - cancer drug
Z.
Babaei
Nanobiotech. Research Lab, School of Chemical Engineering, Babol University of Technology, Babol, I. R. Iran
author
M.
Jahanshahi
Nanobiotech. Research Lab, School of Chemical Engineering, Babol University of Technology, Babol, I. R. Iran
author
M. H.
Sanati
The National Research Center for Genetic Engineering and Biotechnology, Tehran, I. R. Iran
author
text
article
2008
eng
The aim of present study was to prepare gelatin nanoparticle for drug and gene delivery applications. These nanoparticles were prepared by two-step desolvation method. The body distribution of colloidal drug delivery systems was mainly influenced by two physicochemical properties namely particle size and surface characteristics. The influence of several factors on the fabrication process including the amount of desolvating agent, concentration of gelatin, temperature, the amount of glutaraldehyde, organic solvent addition rate and agitation speed was investigated herein. The smallest size of achieved nanoparticles was 168 nm and the largest size was 460 nm which is suitable for drug delivery. The amount of cross linker and organic solvent addition rate have less effect on produced nanoparticle size. The study indicated that a minimum size could be obtained with temperature 60º C, 75 ml acetone and 250 μL glutaraldehyde. To characterize the nanoparticle sample, AFM and SEM were employed whilst size distribution was measured by photon correlation spectroscopy. The mechanistic of the optimum conditions for preparing protein nanoparticles as well as their characterization are discussed.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
23
30
https://www.ijnnonline.net/article_3995_b130654c2fdcfb541ba323fb7e77f7c1.pdf
Photoemission measurements of Ultrathin SiO2 film at low take-off angles
A.
Bahari
Department of physics, University of Mazandaran, Babolsar, I. R. Iran
author
M.
Delshadmanesh
Department of physics, University of Mazandaran, Babolsar, I. R. Iran
author
text
article
2008
eng
The surface and interfacial analysis of silicon oxide film on silicon substrate is particularly crucial in the nano-electronic devices. For this purpose, series of experiments have been demonstrated to grow oxide film on Si (111) substrate. Then these films have been used to study the structure of the film by using X-ray photo emission spectroscopy (XPS) technique. The obtained results indicate that the photoemission measurements on the ultrathin oxide should be done at low take-off angles to emphasize the oxide features.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
31
34
https://www.ijnnonline.net/article_3996_6661df0668198027140617545f2c03aa.pdf
The Edge Szeged Index of One–Pentagonal Carbon Nanocones
A. R.
Ashrafi
Institute of Nanoscience and Nanotechnology, University of Kashan. Kashan 87317-51167, I. R. Iran
author
F.
Gholami-Nezhaad
Institute of Nanoscience and Nanotechnology, University of Kashan. Kashan 87317-51167, I. R. Iran
author
text
article
2008
eng
The edge Szeged index is a new molecular structure descriptor equal to the sum of products mu(e)mv(e) over all edges e = uv of the molecular graph G, where mu(e) is the number of edges which its distance to vertex u is smaller than the distance to vertex v, and nv(e) is defined analogously. In this paper, the edge Szeged index of one-pentagonal carbon nanocone CNC5[n] is computed for the first time.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
35
38
https://www.ijnnonline.net/article_3997_ccf742393404b5ef890457393071e3d3.pdf
Photocatalytic degradation of E. coli bacteria using TiO2/SiO2 nanoparticles with photodeposited platinum
Z.
Ahmadi
College of Chemistry, Iran University of Science and Technology, Narmak,
Tehran, 16844, I. R. Iran
author
Sh.
Afshar
College of Chemistry, Iran University of Science and Technology, Narmak,
Tehran, 16844, I. R. Iran
author
L.
Vafaee
College of Chemistry, Iran University of Science and Technology, Narmak,
Tehran, 16844, I. R. Iran
author
A.
Salehi
Agricultural Department, Saveh Azad University, Saveh, I. R. Iran
author
text
article
2008
eng
In this work, TiO2 /SiO2 (pure anatase), and TiO2 /SiO2 (anatase/rutile) nano-photocatalysts are prepared by using sol-gel method and control of acidity. The particles size is calculated using Scheerer, s equation and is estimated to be around 7-15 nm. In order to improve the photocatalytic activity of TiO2 /SiO2 ,1% (wt) platinum particles are loaded on both catalysts using photoreductive method. SEM images show that doping of Pt particles is not homogenous. FT-IR, BET and UV-Vis Reflectance are used to characterize the structures and properties of photocatalysts. The photocatalytic activities of these catalysts are investigated by their bactericidal activities on E. coli bacteria. 100% destruction of E. coli bacteria has occurred under UV light illumination after 5, 15, 20 and 60 min using Pt-TiO2 /SiO2 (pure anatase), TiO2 /SiO2 (pure anatase), Pt-TiO2 /SiO2 (anatase/rutile) and TiO2 /SiO2 (anatase/rutile) photocatalyst, respectively. The effect of doping Pt is remarkable and rate of destruction using Pt doped catalysts (both catalysts) is three times faster than that of TiO2 /SiO2 catalysts.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
39
48
https://www.ijnnonline.net/article_3998_f032cca66df27aff57eb0b6b495a3421.pdf
Low pressure adsorption of CO2 on multi-wall carbon nanotubes
H.
Delavari Amrei
School of Chemical Engineering, University College of Engineering, University of Tehran, Tehran 11155-4563, I. R. Iran
author
M. R.
Mehrnia
School of Chemical Engineering, University College of Engineering, University of Tehran, Tehran 11155-4563, I. R. Iran
author
A.
Ghanizadeh
School of Chemical Engineering, University College of Engineering, University of Tehran, Tehran 11155-4563, I. R. Iran
author
M. M.
Montazer-Rahmati
School of Chemical Engineering, University College of Engineering, University of Tehran, Tehran 11155-4563, I. R. Iran
author
text
article
2008
eng
Volumetric techniques were employed to study the adsorption of CO2 on a purified multi-wall carbon nanotubes (MWNT’s) sample, as a mesoporous material, at isothermal conditions of 288, 293 and 298 K and pressures ranging from 30 to 150 kPa. Langmuir, Freundlich and Sips equations were used to represent the isotherms. Also the parameters of these fitted isotherm models have been determined. The isosteric heat of adsorption was calculated using Clausius-Clapeyron equation that resulted in an average value of 10.19 kJ/mol (0.106 eV). Adsorption isotherms behavior with temperature and the average value of heat of adsorption confirmed that CO2 adsorption phenomenon is physisorption at the studied ranges. The observed entropy changes related to the adsorption in the range of surface loading from 0.133 to 0.147 mol/kg were lower than the values of theoretical entropy changes for both of the mobile and localized adsorption models.
International Journal of Nanoscience and Nanotechnology
Iranian Nanotechnology Society
1735-7004
4
v.
1
no.
2008
49
58
https://www.ijnnonline.net/article_3999_eafbd85e02843b5a5e27bf4e025c8fb0.pdf