مقالات رزومه سید فرزان تاج بخش

Silk is a natural fiber composed of proteins produced by some insects. Spiders produce protein macromolecules with different molecular structures for different applications. Spider web or other large protein structures are produced by the release of protein fibers from the spinning glands inside the spider's body, which act as a spinning instrument. Spider natural silk has received a lot of attention, due to its unique mechanical and physical properties, thermal resistance, biocompatibility, and biodegradability. These exceptional properties have led to the potential applications of spider silk fibers in production of bulletproof vest, artificial vessels, sensors, and etc. This interesting mechanical and physicochemical properties are due to the macromolecular structure of protein molecules as well as physical interactions between protein chains. derived from protein macromolecule’s structure, including the large protein sequences of the repeating units as well as physical interactions between protein chains and specific mechanisms such as tension, pH adjusting, and ion exchange in spinnerets of spider. Due to the remarkable difficulties in natural production of spider silk, other advanced techniques like inserting spider DNA in animals or bacteria is employed, but fibers produced by these methods do not have mechanical and physicochemical properties of natural spider silk lower molecular weight of the protein chains. Spider silk fibers have potential applications in pharmaceutical and military industries and this study can open a new window to the future of these fibers.

In sulfur recycling units (SRU), due to environmental considerations, increasing efficiency and reducing pollutants have been prioritized, and the most important factors affecting them were process design and the use of appropriate catalysts. In this study, in order to increase the process efficiency, feedback and feedforward control loops along with high percentage (85%) TiO2 catalyst have been used and economic aspects were investigated. The results obtained from SRU Unit 4 of Shahid Hasheminejad Refinery show that the new catalyst increases the temperature difference between different parts of the substrate compared to the usual catalyst and shows an increase in hydrolysis of sulfur compounds and conversion efficiency. The optimal case and the lowest error are created in the case of simultaneous use of both control loops. According to economic estimates, the return on investment is a maximum of one month, and as a result, this plan is economically viable.