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Diatoms biosilica shell, frustule, is substitute biostructures to mesoporous silica particles, which possesses their wide surfaces, nano-diameter porosity, mechanical strength, and thermal stability, optical capabilities, and the ability to bind to biomolecules can be used in biosensing applications. In this study, diatom species called Chaetoceros muelleri, was used for the fabrication of the Fe₂O₃-Au-Biosilica magnetic package. After micro-algae cultivation, the synthesis of gold nanoparticles (AuNPs) on silica walls was carried out using the bio-synthesis method, which evaluations have demonstrated the continuous formation of spherical AuNPs on the walls and its surfaces. After this step, the magnetic iron oxide nanoparticles were attached to the silica surface of the diatom, this, in turn, leads to system guiding using a magnetic field. Surface modification of diatoms magnetic complex, by using the APTES, allowed the attachment of fluorescence Rhodamine and the Herceptin antibody (Trastuzumab) to the structure. As well as the attachment of the fabricated system to target cells (SKBR3) was confirmed by fluorescence microscopic analysis. The results of this study indicate the ability and specificity of the diatom silicone shell as a "multipurpose" package for diagnostic and therapeutic activities.

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Total-Internal-Reflection Fluorescence Microscopy (TIRFM) is a useful tool to visualize and record the phenomena that happens below 100 nm thickness of the sample surface. This unique property of TIRFM help to perform a "qualitative" study of cytoskeleton near the cell-substrate contact. Here,   distribution of actin filaments at cell-substrate interface was imaged by a TIRFM set up. Then, staining the actins cytoskeleton of the human melanoma cell and implementing the prism-based total-internal-reflection fluorescence microscope.  A method to "quantify" distribution of fluorophores at cell-substrate contact is proposed.

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The main aim of this experiment is to investigate the effects of Nano-size Al2O3 on the mechanical properties and microstructure of multi-passes friction stir welding of Al 2024 lap joint. Nano particles were added into the joint line. A combination of rotational speed and travelling speeds were performed. Optical microscopy and scanning electron microscope were used to investigate the microstructure and fracture surface of samples respectively. Optimum condition (sample) was selected due to highest ultimate tensile strength (UTS). It was seen that sample which included Nano particles and fabricated by 1400 rev/min rotational speed and 16 mm/min travelling speed in second pass of continues welding had improvement in UTS in comparison to one pass welded sample of particle free and after that increasing the number of passes reduce the UTS. The average micro hardness of the sample which was particle rich were increased in comparison to particle free sample in nugget zone. Increasing the number of passes was not effect average micro hardness in nugget zone significantly. Grain sizes were reduced by 2 passes welding and after that no significant reduction has been seen.

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Friction Stir Extrusion (FSE) is a modern one step process with high efficiency for conversion and recycling of materials which capable of producing Nano-engineered material via production with good deformability, mechanical and physical properties. Novelty of this production technique is utilization of frictional heat and severe plastic deformation for material flowing, mechanical alloying and finally amendment of powder, chips and other recyclable scraps directly to useful products. Sample’s microstructure was revealed and average grain size was gained for 18 samples. Experimental parameters by use of design of experiments for two factors and analysis of variance were investigated and by the use of experimental results were validated. In this study, the effect of rotational speed in 3 levels and plunge rate in 2 levels were examined on microstructure of produced wires via FSE process. Based on process parameters, there is an equation for grain size prediction was presented by using full factorial design of experiment. Furthermore, normal possibility diagram and residual versus order based on residual theorem were evaluated for systematic error entry and reliability to experimental results. The efficient region on contour diagram reveals that suitable condition of minimum grain size and maximum strength occurred at 250 rpm for rotational speed and 14 mm/min for feed rate. It should be noted that analysis of variance showed that rotational speed, feed rate and interaction of rotational speed and feed rate respectively have a meaningful effect on the grain size of produced wire.

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Friction stir welding (FSW) is a solid-state joining process that leads to several advantages over fusion welding methods as problems associated with cooling from the liquid phase are avoided. In the current research, a new method is presented to improve the microstructure and mechanical properties of joint obtained using FSW. In this method, the joining workpieces are vibrated during FSW. The joining workpieces are fixed on fixture in a butt position and the fixture is vibrated mechanically normal to weld line through camshaft mechanism. The new method is described as friction stir vibration welding (FSVW) process. Microstructure and mechanical properties of welded specimens using FSW and FSVW processes are compared. The results show that weld region grain size of FSV welded specimen is lower than that in specimen welded by FSW for about 30% and the ultimate tensile strength of joint obtained using the former process is higher than that relating to the latter one for about 12%. This is attributed to more generation of dislocations and correspondingly enhanced dynamic recrystallization as vibration is applied. The results also indicate that the weld region grain size of FSV welded specimen increases and mechanical properties of joint decrease as tool rotation speed increases and traverse speed decreases. This is related to temperature increase during FSVW. It is concluded that FSVW is a proper candidate for FSW and its application is recommended for industries.

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Kopeh cheese is one of the traditional Iranian cheeses. In this study, the effect of ripening time on its physicochemical properties was investigated during 187 days of ripening. The results showed that ripening index and pH increased significantly, while "salt in dry matter" decreased (p <0.05). The maximum delta tangent (TD) ranged from 0.35 to 0.4. The Differential Scanning Calorimeter (DSC) curve showed two exothermic peaks for cheese-extracted fat ripened on days 7, 37, 67, and 127; three exothermic peaks for the sample ripened on 97 days, while two exothermic and endothermic peaks for the sample ripened on 187 days, in the cooling phase. The results of principal component analysis (PCA) showed that PC1 and PC2 divided cheeses into four different groups, and PC3 identified only one group, including cheese day 127, with a high correlation with "moisture in the non-fat dry matter", "salt in dry matter," and "fat in dry matter". Also, they showed a significant correlation with TD (p<0.05). These chemicals had the most important impact on the physical properties of Kopeh cheese.

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Although conventional earthquake-resistant systems such as moment frames and braced frames meet the requirements for the safety of a structure when an earthquake occurs, these systems have not guaranteed the prevention of damage to the structure after an earthquake occurs. So that sometimes the repair of some structures seems uneconomic due to these serious damages. Repairing the damage caused by the earthquake was expensive and caused business interruption. A highly effective solution in the new generation of seismic resistance is self-centering systems that eliminate and limit residual drift. The self-centering system's key features affected how the system behaves during earthquakes. The first crucial feature is the amount of post-tensioning (PT) force, which is often used for the standing position after the earthquake. Another one that is played the important role in the behavior of the self-centering system is the energy dissipater element. Employing the damper as a replaceable and cost-effective tool and fuse in self-centering frames to improve energy absorption and damping of structural systems under earthquakes has been considered. A system that can restore the structure to its original state after applying earthquake loads is necessary to minimize damage. Self-centering systems are elements that have the ability to minimize the residual drifts while enduring earthquakes of great intensity.
In this study, flexural damper as an energy dissipator system is employed in the self-centering steel moment frame connections to improve energy absorption, post yielding stiffness, and is easily replaceable after the earthquake. Moreover, providing the sufficient stiffness, strength, and ductility, while reducing permanent deformations in the self-centering steel moment frames subjected to seismic loading have been deliberated. In this paper, after validating the results from the FE model with the prior experimental PT connection, the behavior of the self-centering connection with the flexural damper has been analyzed. In the FE modeling, the geometric and material nonlinearities and preloading strands are contemplated in the modeling. Gap opening and closing action beside contact and sliding phenomena are involved in the models. To achieve this goal, a large-scale experimental test program of analyzed and designed models using the finite element method has been planned. Changing the height of the beam has a great effect on the performance of the moment capacity of self-centering connection. This issue has been tested much less in the experiments and researches carried out until today, but the numerical studies have confirmed this issue. In this research, the change in beam height has been evaluated as one of the main factors in the experiments. According to the test results, the beam and column remained in the elastic range. Also the damage is accumulated in the damper. Flexural dampers can enhance the post-yield stiffness and energy absorption of SF-MRF frames, while maintaining minimal permanent deformation at particular damper thicknesses. The obtained results show that in addition to reducing the residual drift to less than 0.5%, the effective energy the dissipation ratio, β, is also improved to 0.25%. Also, this improvement in the seismic performance of self-centering connection with the flexural damper has been achieved with an acceptable ratio of the moment capacity to the beam plastic moment capacity.