توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱تاثیر نوع حلال در خواص داربست های کامپوزیتی PLGA\nano–HA
نویسنده(ها): ، ، ،
اطلاعات انتشار: یازدهمین کنگره سالانه انجمن مهندسین متالورژی ایران، سال
تعداد صفحات: ۱۰
روش ریخته گری حلال و حل سازی ذره ای از روش های معمول جهت ساخت داربست های کامپوزیتی پلیمر\ سرامیک است. در این روش، نوع حلال مصرفی در خصوصیات نهایی داربست تاثیرگذار است. لذا در تحقیق حاضر، داربست کامپوزیتی پلی لاکتید گلیکولید اسید\ نانو هیدروکسی آپاتیت با دو نوع حلال N– متیل پیرولیدون و دیوکسان تهیه و دو ویژگی درصد تخلخل و نرخ تخریب در نمونه های تهیه شده مورد بررسی قرار گرفته شد. نتایج نشان می دهند که داربست های تهیه شده با حلال دیوکسان درصد تخلخل و سرعت کاهش وزن بیشتری نسبت به داربست های تهیه شده با N– متیل پیرولیدون دارند.

۲Effect of addetive materials on the foaming behavior, cell structure and mechanical properties of Al2O3–ZrO2
نویسنده(ها): ، ، ،
اطلاعات انتشار: دهمین کنفرانس ملی مهندسی ساخت و تولید، سال
تعداد صفحات: ۹
Polymeric sponge replication method is one of the routes that produce ceramic foams. Existence of central triangular voids in struts causes to decrease of mechanical properties and limit their applications. To remove this defect, some additives which consist of Al powder particles and silica sol were added to ceramic slurry which contains Al2O3 and ZrO2 (partially stabilized zirconia). With increasing temperature for pyrolyzing and sintering raw materials, at first, Al powder and glass phase were formed from Al2O3, ZrO2 and SiO2 was melted and was soaked into hollow struts.SEM investigations showed that center of foam struts was free of hollows.XRD considerations depicted there was ZrO2 phase with tetragonal crystallographic structure in the produced foam which could be caused to improve mechanical properties and toughness. Compressive strength of foams increased significantly because of decreasing closed porosity.Weibull statistical study showed remarkable increasing of Weibull module which this value for foams with 10, 20 and 30 ppi was 5.91, 6.06 and 6.53 respectively.<\div>

۳In vitro biocompatibility assessment of POSS\PCU membranes using L929 mouse fibroblasts
نویسنده(ها): ، ، ،
اطلاعات انتشار: سومین کنفرانس نانوساختارها، سال
تعداد صفحات: ۴
Recently, organic–inorganic hybrid nanocomposites based on polyhedral oligomeric silsesquioxane (POSS) due to POSS unique structure and properties have taken much attention especially in biomedical application In this study a unique class of polyurethane i.e. poly (carbonate–urea) urethane membranes containing POSS as molecular reinforcement with superior biological properties was biologically investigated using L–929 cells by means of MTT assay, cell proliferation assay and scanning electron microscopy (SEM) observations. The main purpose was investigation the effect of POSS on biological properties of membranes. Two types of named nannocomposite different in POSS content were prepared. Cytotoxicity evalutions were performed at days of 3, 7 and 14. MTT assay showed very high biocompatibility of the nanocomposite close to 100%, interestingly increase in POSS content led to lower cytotoxicity. Similar tendency was also observed in cell proliferation assay and the sample containing more POSS showed higher proliferation rate of L–929. SEM observations illustrated very good adhesion of L–929 on the surface of the samples. The experiments revealed that POSS has a noticeable effect on biological properties of the nanocomposite, stimulates cell proliferation and enhances cell adhesion properties of the nanocomposite<\div>

۴Study of mechanical properties of pultruded polymer matrix composites (PMC) and the application of composite cross–arms in medium voltage power delivery lines
نویسنده(ها): ، ،
اطلاعات انتشار: دومین کنفرانس بین المللی کامپوزیت، سال
تعداد صفحات: ۵
Due to unique properties and numerous advantages, polymer matrix composites (PMC) have drawn significant attention in various industries and many studies have been performed to replace traditional materials with these new ones. In this investigation by evaluating the mechanical properties of PMCs produced through the pultrusion process with optimum volume fraction (Vf) of unidirectional fibers and calculating the applied forces and torques on power delivery post cross–arms, the modeling was done by ANSYS; As a result the extent of deformation and resistance behavior of composite cross–arms with L profile was obtained.<\div>

۵Fabrication and in–vitro Evaluation of HA\UHMWPE composite as a Bone Substitute
نویسنده(ها): ،
اطلاعات انتشار: چهارمین کنفرانس بین المللی کامپوزیت، سال
تعداد صفحات: ۴
The biological properties of ultrahigh molecular weight polyethylene (UHMWPE) based composites reinforced with hydroxyapatite (HA) particles were evaluated in in–vitro culture. The composites were manufactured by internal mixer and using paraffin oil to overcome the high viscosity of melted UHMWPE. Then, samples were fabricated using compression molding with different contents of HA. The biological properties of the samples were explored by proliferation (MTT) and cell adhesion assays using MG–63 osteoblast cells. Scanning electron microscope (SEM) micrographs revealed that HA particles homogeneously dispersed in UHMWPE by the internal mixer. SEM images exhibited that cell–biomaterial interaction carried out on the surface of the composites and Mg–63 cells with normal phenotypic shape adhered on the surface. Results of MTT assay illustrated that proliferation rate of MG–63 cells in the presence of composite samples with 50 wt. % HA after 7 days of incubation period was 11.27% and 2.7% higher than positive and negative control sample, respectively.<\div>
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