Plasma sprayed nano-hydroxyapatite coatings on titanium alloys
Sabersamandari
Saber-Samandari
New Technologies Research Center, Amirkabir University of Technology, Tehran, Iran
author
text
article
2017
per
Titanium alloys due to have excellent mechanical and biological properties can be a good replacement for bone tissues. However, lack of appropriate bonding between bone and titanium implant leads to separation from the bone. Also hydroxyapatite can be the best material for bone replacing due to chemical and structural similarity to mineral part of bone and good biocompatibility. One cannot use them in load-bearing sites such as bone and teeth due to poor mechanical properties. So the best way for producing biomedical implants is taking advantages of good mechanical properties of titanium implants and biological properties of hydroxyapatite. Therefore hydroxyapatite particles will be coated on titanium or its alloy substrates. In this study hydroxyapatite powder particles coated on titanium alloy substrate. Plasma sprays coating method due to its good properties, easy operation and low cost, will be used in commercial hydroxyapatite coating on the substrate implant. The problems of hydroxyapatite coating using this method are: formation of other calcium phosphate phases, poor adhesion of the coating and the substrate، formation of micro-cracks in the coating due to residual stresses caused by the high temperature process. To this end, hydroxyapatite has been coated on pre-heated titanium alloy in order to improving hydroxyapatite properties. Results indicate that residual stresses decreases in interface and adhesion improved by pre heating substrate.
Advanced Materials and New Coatings
انجمن علمی رنگ ایران
2322-1356
5
v.
20
no.
2017
1407
1413
https://amnc.aut.ac.ir/article_68755_06ab8ecf64bbfaf0032603e9ad4a83f3.pdf
dx.doi.org/AMNC.2017.5.20.1
Synthesis and characterization of CuSbS2 nanocrystals via hot injection route and investigation of sulfur precursor source
Shima
Moosakhani
PhD student, Faculty of Polymer Engineering & Color Tech., Amirkabir University of Technology, Tehran, Iran
PhD student, Color and Polymer Research Center (CPRC), Amirkabir University of Technology, Tehran, Iran
author
Ali Asghar
Sabbagh Alvani
Associate professor, Color and Polymer Research Center (CPRC), Amirkabir University of Technology, Tehran,
Iran
author
Raheleh
Mohammadpour
Assistant professor, Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran, Iran
author
Simo-Pekka
Hannula
Professor, Department of Chemistry and Materials Science, School of Chemical Engineering, Aalto University,
Espoo, Finland
author
text
article
2017
per
In this paper, chalcostibite (CuSbS2) nanocrystals were successfully synthesized via hot injection route. Sulfur precursor source and the effect of it on crystalline structure and morphology have been investigated. Sulfur powder (S) and thiourea (Tu) were used as a sulfur source and particles obtained were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis-NIR spectroscopy. Results revealed that CuSbS2 particles prepared by S had high purity and shape and size uniformity. Moreover, band gap determination studies indicated that direct and indirect values for the powders were 1.49 eV and 1.42 eV, respectively. Small difference between these values confirmed that this material has both direct and indirect band gaps.
Advanced Materials and New Coatings
انجمن علمی رنگ ایران
2322-1356
5
v.
20
no.
2017
1415
1420
https://amnc.aut.ac.ir/article_68756_8f9ba4bc10712af67d1fbd4a706e50bc.pdf
dx.doi.org/AMNC.2017.5.20.2
Synthesis and characterization of MWCNT/PEG@CD nanocomposite as carrier for sustained delivery of Acyclovir
Mohammad Hosein
Ahamadi Azghandi
University of Yasooj, Gachsaran
author
Mosaddegh
Keshavarz
University of Yasooj, Gachsaran
author
Amanollah
Zarei Ahmadi
University of Jondi Shapoor
author
Abolfath
Parhami
Payame Noor University
author
Nasir
Iravani
Azad University of Gachsaran
author
text
article
2017
per
The synthesis of multiwalled carbon nanotubes/poly ethylene glycol and β-cyclodextrin inclusion complex (MWCNT/PEG@ β-CD) as nanoplatform for the loading and delivery of Acyclovir (Acy) drugs is described here. The functionalized multi wall carbon nanotubes (e.g. MWCNT-COOH, MWCNT/PEG and MWCNT/PEG@CD) have been characterized by FTIR and HNMR spectroscopy, electron microscopy (SEM) and differential scanning calorimetry (DSC) to achieve insights on structure, morphology and chemical composition. In this work, the drug binding abilities of MWCNT/PEG@ β-CD nanocomplex towards the Acyclovir (Acy) were proved by UV–vis and DSC experiments. The release studies showed a sustained delivery of Acy without initial burst effect confirming a strong interaction of drug with the nanoplatform sites. Finally, it was approved that the nanocarrier obtained from MWCNT/PEG@CD is able to connect and sustained release of Acy in physiology condition. In agreement with these finding, MWCNT/PEG@CDs hybrid can be proposed as a biocompatible and biodegradation nanotube for loading a variety kind of drug.
Advanced Materials and New Coatings
انجمن علمی رنگ ایران
2322-1356
5
v.
20
no.
2017
1421
1428
https://amnc.aut.ac.ir/article_68760_b26e26fbb3555519c9dd78e4cbc0d559.pdf
dx.doi.org/AMNC.2017.5.20.3
Enhancement of Hydrophilicity in Poly-lactic Glycolic Acid Electrospun Nanofibrous Web
AliAkbar
Merati
Amir Kabir University
author
Masoud
Latifi
Amir Kabir University
author
Fatemeh
Zamani
Amir Kabir University
author
Hosein
Ghanbari Alanegh
Medical University of Tehran
author
Fatemeh
Nadipoor
Amir Kabir University
author
text
article
2017
per
In this study plasma technology was applied on poly-lactic glycolic acid scaffolds to improve their hydrophilicity. The structure of nanofibrous web is modified using a high speed collector is electrospinning process. The general electrospun scaffold was compared with two types of plasma modified and structure modified scaffolds in hydrophilicity view point. Two types of solvents were used for electrospinning solution. The first was pure chloroform and the second was chloroform-dimethyl formaldehyde. We found that the samples that were electrospun with higher collector speed show lower contact angle and consequently higher hydrophilicity. The high speed of collector causes an aligned and regular web formation that improves the hydrophilicity of the electrospun nanofibous scaffold. The results of ATR-FTIR spectra showed that the samples modified by plasma shows enhancement in C=O and C-O groups that can be the reason of hydrophilicity enhancement of scaffolds.
Advanced Materials and New Coatings
انجمن علمی رنگ ایران
2322-1356
5
v.
20
no.
2017
1429
1437
https://amnc.aut.ac.ir/article_68762_dfe3c9d9f9de661023dc63f2a2cf62b1.pdf
dx.doi.org/AMNC.2017.5.20.4
Development of a new method to evaluate chain entanglements density in low entangled UHMWPE and UHMWPE/Graphene nanocomposites
Amin
Heidari
Institute of Polymeric Materials, Polymer Engineering Department, Sahand University of Technology, Tabriz, Iran.
author
Saeed
Talebi
Institute of Polymeric Materials, Polymer Engineering Department, Sahand University of Technology, Tabriz, Iran.
author
Mostafa
Rezaei
Institute of Polymeric Materials, Polymer Engineering Department, Sahand University of Technology, Tabriz, Iran.
author
text
article
2017
per
Several methods such as oscillatory rheometry, by following modulus build up, and solid state nuclear magnetic resonance (NMR) have been introduced to investigate entanglement density of polymers. In this study, we developed a new method to evaluate entanglement density in ultra-high molecular weight polyethylene (UHMWPE) using dynamic mechanical thermal analysis (DMTA). DMTA tests were conducted on films and drawn tapes made from low entangled UHMWPE and UHMWPE nanocomposites containing graphene nano-sheets. In this study, the relation between α-transition temperature and entanglement density was investigated. DMTA results confirmed that as the content of entanglements increased, the chain mobility decreased and the α-transition moved to higher temperatures. It was found that the drawn tapes show a modulus increase with temperature in DMTA due to the tendency of the UHMWPE chains to return to its undrawn state.
Advanced Materials and New Coatings
انجمن علمی رنگ ایران
2322-1356
5
v.
20
no.
2017
1439
1447
https://amnc.aut.ac.ir/article_68785_dab11bc92c4541ebfcaf3a6c7cd8feae.pdf
dx.doi.org/AMNC.2017.5.20.5
Synthesis and Synthesis Mechanism of Piezoelectric Powder Sodium Potassium Anhydride (KNN) Calcified at High and Low Temperatures
مهدی
فیض پور
استادیار، گروه مهندسی مواد، دانشکده فنی مهندسی، دانشگاه آی تالله حائری میبد، یزد
author
تورج
عبادزاده
پژوهشکدۀ سرامیک، پژوهشگاه مواد و انرژی، کرج، البرز
author
text
article
2017
per
The Potassium Sodium Nayobate Ceramic, now known as the KNN, is a lead-free piezoelectric compound due to its good electromechanical properties. The solid state synthesis temperature of KNN powder is generally in the range of 750-950 ° C. In this research, it was examined whether the calcination temperature of KNN powder was still lower and that the zinc absorption and ceramic properties of this low temperature powder were as high as the temperature of the powder? Based on the STA thermal analysis from a mixture of KNN phase precursors, it was found that the temperature range of 550 ± 50 ° C for the synthesis of low-temperature KNN powder can be studied more accurately. Further studies using X-ray diffraction technique showed that double-calcined powders at 550 ° C had no secondary phases or residual materials, especially Nb2O5. The density of the two-hour specimen samples of KNN powder cloned at high temperature (850 ° C) and low temperature (550 ° C) equaled 94% of the density of theoretical measurement. It was found that the secondary phases that can be formed in this system are polysubiable phases formed by the evaporation of alkaline elements, and especially potassium at high temperatures, in both types of ceramic enamel from high-temperature and low-temperature powders . The piezoelectric charge coefficient, the saturation polarization and the retained ceramic of the coated powder at a low temperature were calculated to be 4.30 μC / cm2, 97 pC / N and 24.7 μC / cm2, which is comparable and even higher than The measured values for the coated ceramic from high temperature pyrite are 99 pC / N, 4/29 μC / cm2 and 23.5 μC / cm2 respectively. The results of this study show that without fear of being affected by the final properties of the component, it is possible to reduce the solid state temperature of the KNN.
Advanced Materials and New Coatings
انجمن علمی رنگ ایران
2322-1356
5
v.
20
no.
2017
1449
1469
https://amnc.aut.ac.ir/article_68786_f181b34f918b574e883be146bc5422e7.pdf
dx.doi.org/AMNC.2017.5.20.6
Investigation of water-based binders (organic-inorganic) application on mechanical properties of photocatalytic pseudo-paints
Marieh
Arekhi
Polymer Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology, Tehran
author
Masoud
Jamshidi
Polymer Research Laboratory, Faculty of Chemical Engineering, Iran University of Science and Technology, Tehran
author
text
article
2017
per
Photocatalytic paints are polymer compounds containing the nanocatalyst that are used to break down dangerous air pollutants to low-risk compounds. In this research, photocatalytic pseudo-paint based on water-based acrylic binder with TiO2 pigment and TiO2 nanoparticles was made. In order to improvement of mechanical properties was used from water glass with different amounts in the formulation. Different amounts of TiO2 were used in this organic-inorganic binder composition and was determined the optimized formulation. Dispersion of TiO2 particles in aqueous suspensions and water glass was investigated. Tensile properties of prepared film from organic-inorganic pseudo-paint were compared with organic pseudo-paint and influence of water glass on tensile properties of pseudo-paint was investigated. The results of investigation showed that up to 10% water glass don't cause problem in film formation, whereas beyond this, in the film formation cause problem. The results showed that utilization of 5% water glass obtain the best tensile properties.
Advanced Materials and New Coatings
انجمن علمی رنگ ایران
2322-1356
5
v.
20
no.
2017
1471
1480
https://amnc.aut.ac.ir/article_68787_ab5337164d5cc9539fcc36a08d81bb9e.pdf
dx.doi.org/AMNC.2017.5.20.7