Chemical Engineering / Kimya Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/14

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Now showing 1 - 9 of 9
  • Review
    Citation - WoS: 30
    Citation - Scopus: 33
    Molecular Separation by Using Active and Passive Microfluidic Chip Designs: a Comprehensive Review
    (Wiley, 2023) Ebrahimi, Aliakbar; Didarian, Reza; Shih, Chih-Hsin; Nasseri, Behzad; Ethan Li, Yi-Chen; Shih, Steven; İçöz, Kutay; Tarım, Ergün Alperay; Akpek, Ali; Çeçen, Berivan; Bal Öztürk, Ayça; Güleç, Kadri; Tarım, Burcu Sırma; Tekin, Hüseyin Cumhur
    Separation and identification of molecules and biomolecules such as nucleic acids, proteins, and polysaccharides from complex fluids are known to be important due to unmet needs in various applications. Generally, many different separation techniques, including chromatography, electrophoresis, and magnetophoresis, have been developed to identify the target molecules precisely. However, these techniques are expensive and time consuming. “Lab-on-a-chip” systems with low cost per device, quick analysis capabilities, and minimal sample consumption seem to be ideal candidates for separating particles, cells, blood samples, and molecules. From this perspective, different microfluidic-based techniques have been extensively developed in the past two decades to separate samples with different origins. In this review, “lab-on-a-chip” methods by passive, active, and hybrid approaches for the separation of biomolecules developed in the past decade are comprehensively discussed. Due to the wide variety in the field, it will be impossible to cover every facet of the subject. Therefore, this review paper covers passive and active methods generally used for biomolecule separation. Then, an investigation of the combined sophisticated methods is highlighted. The spotlight also will be shined on the elegance of separation successes in recent years, and the remainder of the article explores how these permit the development of novel techniques. © 2023 The Authors. Advanced Materials Interfaces published by Wiley-VCH GmbH.
  • Article
    Payne Cell Gravimetric Measurements in Polymer-Solvent Systems for Diffusion Coefficients and Isotherm Data
    (Wiley, 2021) Zielinski, John M.; Garcia, Armando R.; Alsoy Altınkaya, Sacide
    The discussion focuses on the application of a Payne cell to the measurement of diffusion and solubility coefficients in polymer/solvent systems. Payne cells have, thus far, been used exclusively to measure steady-state permeation rates of solvents. An analytical model has been developed to describe transient gravimetric sorption and desorption measurements performed with a Payne cell. The model has been validated by a complementary numerical simulation and has been applied to evaluate diffusion and solubility coefficients in two different toluene-silicone rubber systems. The data measured using the Payne cell are found to compare very well with diffusion coefficient and isotherm data measured by traditional gravimetric sorption experiments.
  • Conference Object
    Investigation of Antimicrobial Activity To Determine Mic Value of Cinnamon Bark Oil Against Helicobacter Pylori
    (Wiley, 2014) Güneş, Seda; Becerikli, T.; Tıhmınlıoğlu, Funda; Yılmaz, Özlem
    [No abstract available]
  • Book Part
    Citation - Scopus: 2
    Influence of Filler Surface Modification on the Properties of Pp Composites
    (Wiley, 2015) Balköse, Devrim
    This chapter reviews the fillers have been grouped as silica, glass, silicates, magnesium hydroxide and eggshell, cellulose and carbon, and their surface modification techniques. It explains the effects of the surface modification of fillers on the properties of composite materials having polypropylene as the matrix. The surface modification of fillers affects the properties of the polypropylene matrix composites in different aspects depending on the types of the filler and the modifications. The polypropylene phase was also functionalized by treating PP with MA or ammines. The properties most affected are the tensile strength, Young modulus, and elongation at break of the composites. If crosslinking occurs between the filler and functionalized PP, the tensile strength increases and elongation at break decreases owing to decrease in mobility. PP crystallite formation at the interface also increases the adhesion between filler and matrix. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. All rights reserved.
  • Conference Object
    In Vitro Evaluation of Bioactive Chitosan Microspheres for Eradicating Helicobacter Pylori Biofilm
    (Wiley, 2016) Güneş, Seda; Arslan, Nur; Demiray Gürbüz, Ebru; Tıhmınlıoğlu, Funda; Yılmaz, Özlem
    Certain H. pylori strains can form biofilm both inside and outside human host to protect itself under environmental stress. Biofilm contributes to development of antimicrobial resistance by some kind of mechanisms like providing a barrier for diffusion and allowing resistance gene expression.
  • Conference Object
    Determination of Biofilm Formation by Helicobacter Pylori
    (Wiley, 2016) Arslan, Nur; Güneş, Seda; Demiray Gürbüz, Ebru; Tıhmınlıoğlu, Funda; Yılmaz, Özlem
    Background : Certain H. pylori strains form biofilm in laboratory experiments and also on the surface of gastric mucosa, suggesting possible reason for eradication failure by increasing resistance to antimicrobial agents and transmission. Aim : To examine the mature biofilm formation by H. pylori NCTC11637 standard strain in different incubation periods for H. pylori biofilm characterization.
  • Book Part
    Heterogeneous Catalysis From the Perspective of Surface Science
    (Wiley, 2017) Cihanoğlu, Aydın; Hernan Quinones-Murillo, Diego; Payer, Gizem
    [No abstract available]
  • Book Part
    Citation - Scopus: 11
    Organotin Compounds as Pvc Stabilizers
    (Wiley, 2008) Arkış, Esen
    When poly(vinyl chloride) is fabricated, it passes between rollers (calendars) at about 200 ◦C, which causes elimination of some HCl at allylic defects in the polymer, as shown below (Figure 3.3.1). Furthermore, the released HCl induces further elimination, giving a polyolefin structure with a yellow coloration, which turns red, and then black, after which the polymer becomes brittle. This degeneration can be inhibited by organotin stabilizers, often organotin mercaptides that appear to have two principal functions. Firstly, they react with the HCl to give organotin chlorides, which do not catalyze the elimination process. Secondly, they substitute the chloride at the reactive sites, introducing other groups, such as mercaptide groups, which are not easily eliminated. Organotin maleates may also remove diene units by the Diels–Alder reaction.
  • Article
    Citation - WoS: 30
    Citation - Scopus: 31
    Water and Water Vapor Sorption Studies in Polypropylene-Zeolite Composites
    (Wiley, 2003) Pehlivan, Hilal; Özmıhçı, Filiz; Tıhmınlıoğlu, Funda; Balköse, Devrim; Ülkü, Semra
    Water and water vapor sorption to porous polypropylene-zeolite composites prepared by hot pressing have been studied as a function of zeolite loading. This work presents the first report on the effect of the zeolite as a filler on the water-sorption properties of PP composites. Water swelling experiments were conducted at 25°C using pure PP and PP-zeolite films samples having different zeolite loadings (6-40 wt %). Because PP is a hydrophobic polymer, it does not sorp any water, but the composites having 10, 20, 30, and 40% zeolites have sorbed 0.63, 1.00, 1.72 and 3.74% water, respectively. The zeolite itself at the same conditions sorbed 24.5% water. As the filler loading in the composites increased, equilibrium uptake values increased also. On the other hand, water vapor sorption and kinetics has been studied using a Cahn 2000 gravimetric sorption system. Within in the range of 0.35-0.95% water vapor was adsorbed by the composites containing 10-40 wt % zeolites. Experimental effective water vapor diffusivities of the composite films was about one order of magnitude higher (10-fold) than the experimental water diffusion coefficient in composites. The transport of water in composites was slower than that in the liquid water due to the longer diffusion pathway and adsorption on the surface of the composites. Although the liquid water may fill all the voids in the composite, water vapor is adsorbed on the surface of the zeolite only.