Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Research Project Nanolifli yapıda, sinir büyüme faktörü yüklü mikro küreleri içeren jalatin bazlı doku iskelelerinin hazırlanması ve karakterizasyonu(TÜBİTAK - Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, 2014) Altınkaya, Sacide; Erdal, Esra; Büyüköz, MeldaIn living organisms most of the tissues have the capability of regeneration; on the other hand, this situation is different in mammalian adult neural cells since they loose their ability of proliferation. Compared to peripheral nervous system, central nervous system has restricted regeneration capability which results in trauma, stroke and neuropathology etc. The first studies for the regeneration of nervous system concentrated on the use of autographs, tissue transplanted from one part of the body to another in the same individual, but it has limitations including short-age. Another type of investigation was allograft, which is transplantation of cells isolated from cadavers to the patient, but this approach is also not suitable because of host immune rejection. A new hope to cure neurodegenerative diseases appeared with biomaterials and tissue engineering studies. In this study, it is aimed to develop a novel, nanofibrous scaffolds with the capability of controlled releasing neural growth factor loaded in microspheres. Nanofibrous and oriented scaffolds were prepared from gelatin by a combination of thermally induced phase separation (TIPS), porogen-leaching and molding techniques while alginate microspheres were produced in oil in water emulsion through cross linking of alginate with calcium ions. The bioactivity of the growth factor released from microspheres was determined using PC12 cell line, derived from rat adrenal medulla and differentiate when treated with nerve growth factor. The scaffolds including connected pores with a high porosity, nanofibrous structure which mimic the extracellular matrix and properties similar to natural brain tissure were produced. Compared to solid walled scaffolds, nanofibrous scaffolds allow attachment of cells without any change in their morphologies. Model protein Į-chemotripsin and bovin serum albumin used for protecting the activity of nerve growth factor were loaded in alginate microspheres with an encapsulation efficiency of 100 %. It was found that NGF loaded into microspheres can maintain its activity and it can even differentiate PC-12 cells in a shorter time compared to NGF directly added into cell culture medium.Article Citation - WoS: 3Citation - Scopus: 4Photocatalytic Degradation of Aquatic Organic Pollutants With Zn- and Zr-Based Metalorganic Frameworks: Zif-8 and Uio-66(TÜBİTAK - Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, 2022) Çalık, Fatma Defne; Erdoğan, Bilgesu; Yılmaz, Esra; Saygı, Gizem; Çakıcıoğlu-Özkan, FehimeWater treatment has been an essential issue with the increasing population over 40 years. Researchers center on the major organic pollutants, such as dyes, pesticides, and pharmaceutical products. Photocatalytic degradation is one of the promising methods for aquatic organic pollutant treatment. Over the years, scientists have been working on developments for photocatalysts to enhance their pollutant degradation performances. From the reviewed studies, it is seen that properties like surface area, chemical, mechanical, and thermal stability, and uniform distribution of active sites are crucial, and an increase in these properties provides better degradation efficiency. In this sense, metal-organic frameworks as photocatalysts can be considered more advantageous. This study focuses on the organic aquatic pollutant degradation studies by using well-known MOFs like ZIF-8 and UiO-66 photocatalysts. Mainly the organic dye (RhB, MB, MO, etc.) degradation efficiencies of ZIF-8 and UiO-66 have been achieved to 100%. Recently, the degradation capacities of various pharmaceuticals such as diazinon, acetaminophen, levofloxacin, and sulfamethoxazole have also been investigated. According to the reviewed studies, ZIF-8 and UiO-66 can be considered remarkable photocatalysts for the degradation of organic pollutants.Article Citation - WoS: 4Citation - Scopus: 5Co2 Absorption Into Primary and Secondary Amine Aqueous Solutions With and Without Copper Ions in a Bubble Column(TÜBİTAK - Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, 2022) Yousefzadeh, Hamed; Güler, Cansu; Erkey, Can; Uzunlar, ErdalChemical absorption of CO2 into aqueous amine solutions using a nonstirred bubble column was experimentally investigated. The performance of CO2 absorption of four different primary and secondary amines including monoethanolamine (MEA), piperazine (PZ), 2-piperidineethanol (2PE), and homopiperazine (HPZ) were compared. The effects of initial concentration of amine, the inlet mole fraction of CO2, and solution temperature on the rate of CO2 absorption and CO2 loading (mol CO2/mol amine) were studied in the range of 0.02–1 M, 0.10–0.15, and 25–40 °C, respectively. The effect of the presence of copper ions in the amine solution on CO2 loading was also studied. By comparison of the breakthrough curves of the amines at different operational conditions, it was revealed that the shortest and longest time for the appearance of the breakthrough point was observed for MEA and HPZ solutions, respectively. CO2 loading of MEA, 2PE, PZ, and HPZ aqueous solutions at 25 °C, 0.2 M of initial concentration of amine, and 0.15 of inlet mole fraction of CO2 were 1.06, 1.14, 1.13, and 1.18 mol CO2/mol amine, respectively. By decreasing the inlet mole fraction of CO2 from 0.15 to 0.10, CO2 loading slightly decreased. As the initial concentration of amine and temperature decreased, CO2 loading increased. Also, the presence of copper ions in the absorbent solution resulted in a decrease in the CO2 loading of MEA and HPZ aqueous solutions. In case of PZ and 2PE amines, adding copper ions led to precipitation even at low copper ion concentrations.