Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Article Citation - WoS: 5Citation - Scopus: 5Evaluation of Liposomal and Microbubbles Mediated Delivery of Doxorubicin in Two-Dimensional (2d) and Three-Dimensional (3d) Models for Breast Cancer(Galenos Publishing House, 2021) Aydın,M.; Özdemir,E.; Altun,Z.; Kılıç,S.; Aktaş,S.Objective: Liposomal cancer treatment strategies are useful in removing the side effects that were the main concern in recent years. In this study, we prepared microbubble (MBs) conjugated with DOX-loaded liposomes (DOX-loaded MBs) and investigated their effectiveness in in vitro breast cancer cells in two dimensions (2D) and three dimensions (3D). Materials and Methods: With this aim, breast cancer cells with different features (4T1, MDA-MB231, MCF-7) were growth in 2D and 3D dimensions. The cytotoxic and cell death effects under different conditions, durations and doses were evaluated with WST-1, trypan-blue, colony counts. Apoptotic effects were investigated with flow cytometric Annexin-V-PI and immunohistochemical (Ki-67, caspase 3, 8, 9) methods. Results: After free DOX and LipoDOX were applied, the proliferation index of three cell lines reduced. Intrinsic and extrinsic apoptotic pathways were activated in both 2D and 3D models. However, this effect was observed at lower levels in the 3D model due to the difficulty of diffusion of DOX into the spheroids. Additionally, the suitability of the 3D model for breast cancer cells was supported by formation of ductus-like structures and spheroids. Cell deaths were not observed significantly with the DOX-loaded microbubbles due to rising of MBs to the surface and not reaching spheroids held in matrigel of 3D model. Conclusion: DOX and LipoDOX showed anti-proliferative and apoptosis-inducing effects in breast cancer cells. However, these effects indicated variability depending on the cell lines and 2D or 3D model types. ©Copyright 2021 by the the Turkish Federation of Breast Diseases Societies.Article Citation - WoS: 17Citation - Scopus: 19Heavy Naphtha Upgrading by Catalytic Reforming Over Novel Bi-Functional Zeolite Catalyst(Springer, 2018) Ahmedzeki, Nada S.; Al-Tabbakh, Ban A.; Antwan, Maher B.; Yılmaz, SelahattinNaphtha catalytic reforming process using bimetallic platinum and titanium loaded on nano synthesized HY zeolite was investigated for the product octane number enhancement. The activity of five samples of the prepared catalyst with different bimetallic loading of 0.13, 0.25 wt% Pt and 0.75, 1, 2.2 wt% Ti were investigated for Iraqi heavy naphtha catalytic reforming at the temperature range of 490, 500 and 510 degrees C and pressure of 10 bar in a packed bed pilot plant reactor. The best result of the research octane number was 84 for reformate product using the sample of 0.13% Pt-0.75% Ti%/HY zeolite at temperature 510 degrees C and 10 bar achieving 47% increase. All samples of the prepared catalyst showed a good stability during the operation at severe conditions and the maximum carbon content was about 9% due to the deposition of coke precursor on the catalyst surface. The reformate yield was investigated for all catalyst samples under 10 and 20 bars and the same range of temperature and ranged from 89 to 94%. These results are encouraging for future possible replacement of the conventional catalyst by the local synthetic zeolite. Octane number was correlated on the basis of constituent's boiling points. The maximum absolute error between the experimental and predicted octane number was about 3 and 5% using 10 and 20 bar respectively.Article Effective Synthesis of Cetyl Palmitate Over Co-Precipitated Wo3-Zro2 Catalysts(Springer Verlag, 2018) Mutlu, Vahide N.; Yılmaz, SelahattinThis study is focused on the development of solid acid catalysts for the synthesis of long chain fatty acids. A series of WO3-ZrO2 catalysts were prepared by co-precipitation method and tested in the synthesis of cetyl palmitate. The effect of WO3 loading (10, 15, and 20 wt% WO3) and calcination temperature (700 and 800 degrees C) on the catalyst properties and activity was investigated. XRD and Raman analysis confirmed that WO3 loading stabilized the tetragonal zirconia phase. Higher calcination temperature enhanced the acidities of the catalysts. WO3-ZrO2 catalysts were found to be very efficient for the synthesis of cetyl palmitate with high selectivity. These catalysts were tested for different reaction temperatures (135 and 162 degrees C), feed composition and catalyst amounts. The highest cetyl palmitate yield (98.4%) was obtained over the catalyst calcined at 800 degrees C with 15 wt% WO3, which had the highest total acidity. The catalysts preserved their activities up to three reuse.Article Citation - WoS: 1Citation - Scopus: 1Mineralization of Olive Mill Wastewater Under Hydrothermal Conditions(Desalination Publications, 2019) Ersanlı, Çağlar; Yüksel Özşen, AslıOlive mill wastewater (OMW) is highly dangerous for land and aquatic environments because of its high phenolic content, acidity, and salinity. Hence, hydrothermal degradation of OMW in subcritical water medium with and without using external oxidizer (H2O2) was studied to decrease its total organic carbon (TOC), total phenolic content (TPC), and color. Effects of reaction temperature (150 degrees C-250 degrees C), reaction time (30-120 min), and H2O2 content (0-100 mM) on TOC and TPC of OMW were investigated. Box-Behnken-type experimental design and statistical analysis (analysis of variance) were practiced by Design Expert 11. According to statistical analysis, effect of reaction temperature significantly affected TOC removal efficiency. The best TOC reduction (31.65%) was achieved without using H2O2 at 250 degrees C for 120 min.Article Citation - WoS: 11Citation - Scopus: 11Effect of Different Acidity Modifications on the Activity and Selectivity on H-Zsm5 Zeolites in N-Butene Isomerization(Springer Verlag, 2014) Kılıç, Emre; Yılmaz, SelahattinH-ZSM-5 was modified by silylation [tetraethylorthosilicate (TEOS) and triaminopropyltriethoxysilane], alkali (NaOH), acid (HCl) and ammoniumhexafluorosilicate (AHFS) treatments. The parent and modified zeolite forms were tested in n-butene isomerization. Modifications affected total acidities, the strength of the acid sites, pore sizes and surface areas of the H-ZSM-5 differently. The modifications decreased the conversion obtained by the parent catalyst. TEOS and alkali modifications did not promote formation of isobutene. Pre-alkali treatment before acid treatment increased selectivity to isobutene from 56.0 to 66.7 %, while conversion changed a little, it dropped from 52 to 50 %. AHFS modification provided the highest enhancement in selectivity to isobutene (87.5 %) for which n-butene conversion was dropped by about 10 % compared to H-ZSM-5. This was attributed to a slight modification of the pore size and to the reduction in strong and weak acid sites and generation of new Lewis acid sites.Article Citation - Scopus: 1The Effect of Bio-Based Plasticizer on the Permanence and Water Vapour Transport Properties of Pvc Plastigels(Serbian Chemical Society, 2008) Okieimen, Felix Ebhodaghe; Egbuchunam, Theresa Obuajulu; Balköse, DevrimNovel formulations of PVC plastisols based on blends of bio-based and synthetic plasticizers were prepared and characterized. A traditional phthalate plasticizer, dioctylphthalate, was replaced in the plastisols studied by the epoxidized rubber seed oil (4.5 % oxirane content). The plastisols formed were processed into plastigels and characterized in terms of permanence properties using leaching and migration tests and water vapour barrier properties. It was found that the permanence properties of PVC/DOP plastigels were maintained in the presence of up to 50 % ERSO, and that blending with DOP did not impair the water barrier properties of PVC plastigels.