فهرست مطالب m. vaezi

Using coarse-grained molecular dynamics (CGMD), the simulations of the nanostructures are performed considerably faster and with low computational costs. In the present study, a coarse-grained model is proposed for describing the surface assembly of a molecular machine called a nanotruck. In this model, we assumed that the interactions of fullerene wheels have the main role in the nanocars interactions. The analysis of the potential energy reveals three stable configurations in the interaction of two nanocars. The stable configuration of nanocars obtained from the coarse-grained model is in agreement with the results of the all-atom molecular dynamics simulations. Simulating the stable configurations at temperatures of , and, K, we examined the thermal stability and separation of nanocars. Since each stable configuration shows a specific radius of gyration, we employed this parameter to study the thermal stability of configurations at different temperatures. At K, the nanocars maintain their stable configurations, and at the temperature of K, the nanocars are able to change their relative orientations. The thermal energy supplied at K and higher temperatures is sufficient to break the cluster of two nanocars, and the molecules are separated at this temperature range. The potential energy of the interaction of two molecules finds zero value during the simulation time, which refers to the separation of nanotrucks at this temperature. In the next step, we evaluate the surface arrangement of larger clusters, including four and eight nanocars. Considering the relative orientations of each pair of neighboring nanocars, it is concluded that the stable orientations of nanocars are similar to those observed in the cluster of two nanocars. The results of the coarse-grained model on the assembly of nanocars are consistent with the conclusions of the all-atom simulations of nanocars. The proposed coarse-grained model can be employed to study the assembly of other fullerene-based nanocars.

There are several attempts to improve surface characteristics of biomaterials with thick film coatings. In this research, a class of protective coating layers of bi-layered Hydroxyapatite (HA)/Al2O3-SiO2 (with 10, 20, 30 %wt SiO2) were deposited on titanium (Ti) surfaces by plasma spray technique. The surface features of the applied coating layers were evaluated in detail to confirm the effectiveness of the technique for further biomedical applications. The results demonstrated that uniform and bi-layered plasma sprayed coatings can be successfully prepared through the optimization of engineering parameters. Also, it was found that the roughness of the bi-layered coatings increases with increasing the number of coating layers. The corrosion behavior of the coated and uncoated samples was comparatively investigated using electrochemical tests. The measured current densities (icorr) for HA, (HA)/Al2O3-SiO2 (with 10, 20, 30 %wt SiO2) were 0.27μA/cm2, 0.28 μA/cm2, 0.23 μA/cm2, 0.79 μA/cm2, respectively. According to the results, corrosion resistance of samples with 20% SiO2 is significantly improved compared to the single-layer HA and bare Ti. The outcomes of FESEM results revealed that porosity and cavities related to evaporation of adhesive PVA and it is confirmed by increasing the percentage of silica to more than 20%, porosity has increased. In conclusion, the proposed coating system showed promising abilities for future biomedical applications. It could be optimized and improved by changing the structural characteristics of the substrate, chemical composition and porosity of the coating layers.

In this study, the effects of three different viscous damper configurations, chevron, diagonal and toggle, as well as brace stiffness on the performance of brace-viscous damper system in various steel frams under different earthquake records were investigated. A finite element software, ANSYS, is exploited to develop the numerical models. To verify the numerical simulations, their results were compared with those of the experimental studies in the literature. The results show the reduction in the base shear force given by the toggle configuration is larger than that due to the chevron and diagonal configurations. Regarding the brace stiffness (area), for a reference damping coefficient of 500 N.m/s, a 54% increase in the brace area (from 42 to 91.8 mm2) results in a 21.26, 38.61, and 17.57% reduction in the structure displacement response for the diagonal, chevron, and toggle configurations, respectively. Further, using the results of the numerical simulations, we proposed the spatially-optimized distribution of the brace-viscous damper system.

Urban public spaces are used for compulsory, voluntarily, and, more importantly, social activities and women certainly have the right to play an active role in, and they should benefit from equal right the same as men. This study aimed to address the amount of adaptation of public spaces in zone 8 of Tabriz the needs of women. The present study is applied and, in essence, is descriptive-analytic. 242 questionnaires were distributed, according to the Cochran formula, among women and data were analyzed using Factor-analysis and t-Test. The Cronbach Alpha was 88/3 which is ‘good’. The questions, based on Exploratory Factor Analysis model, have been categorized into four factors: physical, accessibility, social-cultural, and security. Overall, these factors specify %68/32 of variance of the variables. The result shows that the factors of infrastructure of physical, accessibility, social-cultural with the levels of significance, 0/04, 0/01, and 0/03, respectively, are not adapted desirably to the needs of women, but the level of significance for the security factor (0/217) shows a suitable condition through the lens of the respondents. According to results and due to the fact that citizens and tourists visit the zone regularly, this issue should be taken into account significantly by the authorities and the related organizations.

In late 19th and 20th century, much has happend for the peacefulsettlement of disputes, taking full account of the recent developmentsinstead of the use of force. After much travail the internationalconferences have been created, the system for addressing disputes setup by the conventions, come into force. As with other means of disputesettlement is the process of mediation. The cases just considered arewhat the author indicates about the kinds of concerns that induce thisway of settlement: political, legal and technical questions and alsothe dispute itself. The purpose of this article is a completely referenceto a definitive overview of mediation of disputes to the litigation,mediator, mediation clauses. The author has produced a critique ofthe mediation with special focus on litigations.