Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Article Citation - WoS: 1Citation - Scopus: 1Inhibition of Caco3 Growth and Synthesis of Submicron Particles by Preferential Adsorption of Additive Ca2+ Ions on Fresh Precipitates(Royal Society of Chemistry, 2022) Majekodunmi, Olukayode T.; Kılıç Özdemir, Sevgi; Özdemir, Ekrem; Kılıç Özdemir, Sevgi; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyThis study demonstrates a method to inhibit the growth of CaCO3 and synthesize submicron particles in a chemical precipitation process under ambient and high supersaturation conditions. Equimolar CaCl2 and Na2CO3 solutions were mixed in a model tubular reactor at a constant flow rate, and the precipitates were continuously dispersed in stirred 250 mL of 10 mM Ca(OH)2 solution. This approach resulted in the synthesis of colloidally stable submicron CaCO3 particles for a precipitant concentration ≤75 mM. Varying the precipitates’ retention time in the tubular reactor had no significant effects on the particle size and colloidal stability. Time-dependent changes in the mean size, crystal form, morphology and specific surface area of the synthesized particles were also studied. For a precipitant concentration of 75 mM, the particles were monodispersed and porous spindle-like scalenohedral crystals which gradually grew in all faces as more precipitates were fed into the Ca(OH)2 solution. The mean hydrodynamic size of the particles was ∼850 nm at the 8th minute. However, in the absence of additive Ca2+ ions, the particles obtained at the 8th minute were polydisperse mixtures of vaterite and rhombohedral calcite particles greater than 4 μm in size. The results show that free additive Ca2+ ions are irreversibly adsorbed onto the particles as the precipitates dissolve and recrystallize into smaller crystals upon reaching the Ca(OH)2 solution.Article Citation - WoS: 14Xenograft Tumor Volume Measurement in Nude Mice: Estimation of 3d Ultrasound Volume Measurements Based on Manual Caliper Measurements(Dokuz Eylül Üniversitesi, 2020) Barış, Mustafa; Kılıç Özdemir, Sevgi; Serinan, Efe; Çalışır, Meryem; Şimşek, Kürşat; Aktaş, Safiye; Yılmaz, Osman; Seçil, Mustafa; Kılıç Özdemir, Sevgi; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyObjectives: Volume measurement of subcutaneous xenograft tumors in nude mice models is an important metric to assess tumor growth or response to therapy. Manual calipers are widely used for this purpose. But the measurements with manual calipers may be inaccurate. Contrarily, three-dimensional (3D) ultrasonographic measurements give reliable and accurate tumor volume calculation. We aim to; evaluate the accuracy of common four formulas given in the literature to estimate xenograft tumor volumes based on manual caliper measurements and offer a new coefficient for a better estimation of the tumor volumes. Patients and Methods: Detailed manual diameter measurements of xenograft tumors were in 14 nude mice performed using Vernier caliper. Tumor volumes were calculated using the suggested formulas in the literature based on manual measurements. 3D ultrasound volume measurements were performed on same xenograft tumors using high resolution Vevo 2100 imaging system. To propose a new coefficient; means of ratio between manual and ultrasound volume measurement values were used. Also, data set was divided into two subgroups as tumor volume under 800 mm3 and over 800 mm3. New coefficients for each subgroup were defined. Results: Only with prolate ellipsoid formula there was no statistically significant difference between volume measurements with two methods (p=0,24). Our proposed formula (0,45 L*W*H) could estimate tumor volumes as good as prolate ellipsoid formula. Coefficient 0,35 and 0,81 in the same formula were found efficient in the selected subgroups. Conclusion: Using one common coefficient/formula for tumor volume estimation in any tumor size can be inaccurate. Appropriate coefficient should be chosen according to the dataset worked with.Conference Object Investigation of Therapeutic Effects of Doxorubicin Loaded Microbubbles in In-Vivo Breast Cancer Model(Springer, 2017) Serinan, Efe Özgür; Özdemir, Ekrem; Barış, Mustafa; Kılıç Özdemir, Sevgi; Kürkçü, Gülşah; Önercan, Cansu; Çalışır, Meryem; Altun, Zekiye; Aktaş, Safiye; Aydın, Melek; Kılıç Özdemir, Sevgi; Yılmaz, Osman; Özdemir, Ekrem; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology[No abstract available]