Farsi M.,Islamic Azad University at Sari
Journal of Reinforced Plastics and Composites | Year: 2010
This study deals with the effect of chemical modification of wood flour by components including alkaline, silane, acrylic acid and benzoyl chloride, and PP-g-MA coupling agent concentration (0 and 3 wt%) on the mechanical performance of WPCs. The samples were fabricated by melt compounding in an internal mixer and then injection molding. Tensile, flexural, and Izod impact test of modified composites were performed and compared by net polypropylene and unmodified samples. The results showed that the highest tensile and flexural resistance was observed in composites modified with alkaline and including coupling agent. Modified composites had lower impact strength than unmodified ones. Simultaneous use of chemical modification and coupling agent on mechanical properties had synergic effect. Therefore, chemical modification of wood flour improved interfacial adhesion and so increased the mechanical performance of these composites. © 2010 The Author(s).
Nozari K.,Islamic Azad University at Sari |
Pedram P.,Islamic Azad University at Tehran
Europhysics Letters | Year: 2010
In this paper we study the effects of the Generalized Uncertainty Principle (GUP) on the spectrum of a particle that is bouncing vertically and elastically on a smooth reflecting floor in the Earth's gravitational field (a quantum bouncer). We calculate energy levels and corresponding wave functions of this system in terms of the GUP parameter. We compare the outcomes of our study with the results obtained from elementary quantum mechanics. A potential application of the present study is discussed finally. Copyright © EPLA, 2010.
Farsi M.,Islamic Azad University at Sari
Fibers and Polymers | Year: 2012
The objective of this investigation was to evaluate the mechanical, thermal stability and viscoelastic behaviors of experimental PP composites made from wheat straw and PP-g-MA coupling agent. Four levels of wheat straw, 10, 20, 25 and 30 wt % and two levels of coupling agent, 0 and 3 % wt were mixed with PP in rotary type mixer and injection molding process, respectively. Tensile characteristics and impact strength, thermal gravity and dynamic mechanical and thermal analysis of the samples were evaluated. Based on the results, it was observed that the tensile properties increased and impact strength decreased with the increase in the fiber loading from 10 % to 30 %. Further, the composites treated with PP-g-MA exhibited improved mechanical properties which confirmed efficient fiber-matrix adhesion. DMT analysis showed that the PP composites made of 30 % wheat straw containing 3 % PP-g-MA showed the highest E' and lowest tan δ than the untreated ones. Also, the thermal stability of wheat straw was lower than PP and as filler content in the composites increased, the thermal stability decreased and the ash content increased. © 2012 The Korean Fiber Society and Springer Netherlands.
Darvishi Khezri H.,Islamic Azad University at Sari
Saudi journal of kidney diseases and transplantation : an official publication of the Saudi Center for Organ Transplantation, Saudi Arabia | Year: 2014
Poor sleep quality is a common problem that can potentially predict mortality risk and quality of life in hemodialysis (HD) patients. Also, inflammation is a common feature in HD patients. To determine sleep quality and its correlation with serum C-reactive protein (CRP) level in these patients, we studied 132 chronic HD patients in two university-affiliated teaching hospitals in Sari, Iran during September 2010. Pittsburgh Sleep Quality Index was employed to assess the sleep quality of the patients in addition to CRP, albumin, cholesterol, phosphorus and hemoglobin levels. There were 104 (78.7%) patients who suffered from poor sleep quality. A significant correlation was found between serum CRP level and the patients' sleep quality (P <0.05). There was also a significant correlation between sleep quality and serum phosphorus and albumin levels and body mass index (P <0.05). Furthermore, a significant positive correlation existed between the different components of sleep quality and CRP (P <0.05). We conclude that there is a correlation between decreased sleep quality in HD patients and elevated CRP levels, which may have therapeutic implications.
Moradi S.E.,Islamic Azad University at Sari
Journal of Industrial and Engineering Chemistry | Year: 2014
Highly ordered mesoporous carbon (OMC) has been prepared and modified with a anionic surfactant sodium dodecyl sulphate (SDS) by microwave heating technique and used as an efficient sorbent for methylene blue (MB) dye removal from wastewater. The structural order and textural properties of the adsorbents was studied by XRD, BET, FT-IR, Raman and TGA analyses. Adsorption experiments were conducted in batch mode with the variables such as amount of adsorbent, agitation speed, contact time, temperature, initial solution concentration and solution pH. The MB dye removal for microwave and impregnation methods modified SDS-OMC and OMC were found to be 95.3, 88.4 and 68%, respectively. © 2013 The Korean Society of Industrial and Engineering Chemistry.