Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Book Part Heterogeneous Catalysis Fromthe Perspective of Surface Science(Wiley, 2016) Cihanoğlu, A.; Quiñones-Murillo, D.H.; Payer, G.This chapter discusses the historical development of surface chemistry. During the period 1860 – 1912, the surface chemistry of catalysis made progress as a result of many experimental observations of scientists, such as in oxidation of hydrogen chloride, SO2oxidation to SO3, the reaction of methane with steam to form CO and H2, the oxidation of ammonia, ethylene hydrogenation, and the synthesis of ammonia. Catalytic technology has to be complemented by advancements in the chemical industry. The development of catalytic technology is closely related not only to the technological advances in the chemical industry, but also to significant political concerns. Most of the particulate materials used as heterogeneous catalysts present some limitations such as low stability, formation of agglomerates, and little selectivity, these conditions are likely to be due to weak surface conditions rather than bulk deficiencies themselves; surface optimization can improve the performance in materials that already have the necessary bulk properties. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Boschstr. 12, 69469 Weinheim, Germany. All rights reserved.Book Part Citation - Scopus: 1Influence of Surface Treatment of Fillers on Mechanical, Surface, and Water Sorption Behavior of Natural-Fiber Polypropylene Composites(Wiley, 2016) Atikler, U.; Tihminlioglu, F.The objective of this chapter is to prepare polypropylene (PP)/lignocellulosic fiber composites composed of three different natural fibers, CE, SD, and wheat straw (WS), and to investigate the effects of surface treatment type and amount of coupling agents on the mechanical, morphological, and water uptake properties of PP/fiber composites. Two silane coupling agents, namely (3-aminopropyl)-triethoxysilane (AS) and methacryloxy propyl trimethoxy silane (MS), and maleic anhydride polypropylene copolymers (MAPP) were employed in order to increase the compatibility between the fiber and the matrix. The improvement in the interfacial interaction was also confirmed by using the Pukánszky model. Mechanical test results clearly showed that both silane and MAPP treatments increased the tensile strength and Young's modulus. Mechanical test and water sorption results and scanning electron micrographs (SEMs) of the PP/fiber composites indicated that PP composites containing SD treated with MAPP experienced maximum improvement concerning compatibility and interfacial adhesion between the fiber and the matrix. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Boschstr. 12, 69469 Weinheim, Germany. All rights reserved.Article Citation - WoS: 11Citation - Scopus: 8Local Well-Posedness of the Higher-Order Nonlinear Schrödinger Equation on the Half-Line: Single-Boundary Condition Case(Wiley, 2024) Alkın, A.; Mantzavinos, D.; Özsarı, T.We establish local well-posedness in the sense of Hadamard for a certain third-order nonlinear Schrödinger equation with a multiterm linear part and a general power nonlinearity, known as higher-order nonlinear Schrödinger equation, formulated on the half-line (Formula presented.). We consider the scenario of associated coefficients such that only one boundary condition is required and hence assume a general nonhomogeneous boundary datum of Dirichlet type at (Formula presented.). Our functional framework centers around fractional Sobolev spaces (Formula presented.) with respect to the spatial variable. We treat both high regularity ((Formula presented.)) and low regularity ((Formula presented.)) solutions: in the former setting, the relevant nonlinearity can be handled via the Banach algebra property; in the latter setting, however, this is no longer the case and, instead, delicate Strichartz estimates must be established. This task is especially challenging in the framework of nonhomogeneous initial-boundary value problems, as it involves proving boundary-type Strichartz estimates that are not common in the study of Cauchy (initial value) problems. The linear analysis, which forms the core of this work, crucially relies on a weak solution formulation defined through the novel solution formulae obtained via the Fokas method (also known as the unified transform) for the associated forced linear problem. In this connection, we note that the higher-order Schrödinger equation comes with an increased level of difficulty due to the presence of more than one spatial derivatives in the linear part of the equation. This feature manifests itself via several complications throughout the analysis, including (i) analyticity issues related to complex square roots, which require careful treatment of branch cuts and deformations of integration contours; (ii) singularities that emerge upon changes of variables in the Fourier analysis arguments; and (iii) complicated oscillatory kernels in the weak solution formula for the linear initial-boundary value problem, which require a subtle analysis of the dispersion in terms of the regularity of the boundary data. The present work provides a first, complete treatment via the Fokas method of a nonhomogeneous initial-boundary value problem for a partial differential equation associated with a multiterm linear differential operator. © 2023 Wiley Periodicals LLC.Article Citation - WoS: 17Citation - Scopus: 18Incorporation of Organic Acids Turns Classically Brittle Zein Films into Flexible Antimicrobial Packaging Materials(Wiley, 2022) Sozbilen, G.S.; Çavdaroğlu, E.; Yemenicioglu, A.This study aimed to turn classically brittle zein films into flexible antimicrobial ones by the use of lactic (LA), malic (MA) and tartaric acids (TA). The most effective plasticizer was LA (400% elongation at break [EB] at 4%), while MA (189% EB at 4.5%) and TA (68% EB at 5%) showed moderate and limited plasticizing effects, respectively. The LA- and MA-loaded films maintained their flexibility during 30-day storage at 4°C or 25°C. Fourier transform infrared (FTIR) analysis suggested that the plasticization of LA and MA could be related to secondary structural changes in zein such as increased α-helix and random coils (mainly by MA) and spaced/modified intermolecular (only by LA) and intramolecular (mainly by MA) β-sheets. Atomic force and scanning electron microscopy showed that LA and MA gave more homogenous and smoother films than TA. Films with LA showed the highest water vapour permeability followed by those of control, MA- and TA-loaded films. Films with 3%–4% LA or MA formed clear zones on Listeria innocua and Klebsiella pneumonia, but only films with LA formed clear zones on Escherichia coli. All OA-loaded films gave unclear zones on Staphylococcus aureus in disc-diffusion tests, but this bacterium was inactivated rapidly in antimicrobial tests based on surface inoculation tests. LA is the best OA to develop flexible antimicrobial films from zein, an industrial by-product that films could not have been utilized as a widespread packaging material due to their brittleness. © 2021 John Wiley & Sons, Ltd.Book Part Arsenic Removal by Electrocoagulation(Wiley, 2022) Gören, Ayşegül Yağmur; Kobya, MehmetBecause of the toxic impacts on human health, the arsenic (As) limit value in drinking water was decreased from 50 to 10 ?g l-1 by the relevant authorities (WHO 1993; US EPA 2001). In this case, the problem of As pollution in natural water resources used for drinking water has grown even more and turned into a global crisis. According to reports in many parts of the world, over about 230 million people appear to be affected by high arsenic concentrations in groundwater. In this case, it turned out that there was a great need for cost-effective and environmentally friendly technologies from drinking water sources. One of the emerging water treatment technologies in recent years is electrocoagulation (EC) and it has been seen that it is effective in treating As (>99%) from water and eliminates some of the disadvantages of other conventional treatment processes. EC method includes electro-oxidation of anode electrode materials (iron and aluminum) and in situ production of coagulant agents. From groundwater resources with As content of 5-1000 ?g l-1, As removal efficiencies and operating costs (OCS) of EC technology using iron (Fe) and aluminum (Al) anodes were 85.0-99.9% and 0.0020-1.04 US$ m-3, respectively. Different types (plate, scrap, rod, and ball) of electrodes were used for As removal with the EC process, and it was observed that Fe electrodes or Fe-Al hybrid electrodes performed better in As removal. In addition, it has been determined that arsenate (As(V)) removal is more effective than arsenite (As(III)). A significant quantity of As(III) is oxidized in the EC process, resulting in precipitation, adsorption, and metal-oxy hydroxylic complex reactions. EC process has a lower OC to achieve As removal below the permissible WHO value compared to conventional treatment processes, accomplishing it as a further applicable option for As removal. © 2023 John Wiley & Sons, Inc.Book Part Citation - Scopus: 2Influence of Filler Surface Modification on the Properties of Pp Composites(Wiley, 2015) Balköse, DevrimThis 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.Book Part Citation - Scopus: 6Quality Assessment of Aquatic Foods by Machine Vision, Electronic Nose, and Electronic Tongue(Wiley, 2010) Korel, Figen; Balaban, Murat ÖmerThe increase in demand for seafood products has catalyzed the desire for higher standards regarding safety and quality issues. Since seafoods are perishable, freshness is a major quality parameter to be considered [1,2]. There is no unique freshness or spoilage indicator for seafood, therefore combinations of selected indicators need to be used to evaluate freshness [3,4]. An important and widely used method to determine freshness is sensory evaluation [5]. The Quality Index Method (QIM) uses a demerit point scoring system [6] based on the evaluation of the important sensory attributes (odour, texture, and appearance) of fish and other aquatic foods. The sensory quality is expressed by the sum of the demerit points, and a linear correlation between these points and the storage time is used to predict the freshness of the target seafood [5,7,8]. The QIM has been developed for various seafood species and products, such as Atlantic mackerel (Scomber scombrus), horse mackerel (Trachurus trachurus), European sardine (Sardina pilchardus) [9], gilthead seabream (Sparus aurata) [10], farmed Atlantic salmon (Salmo salar) [11,12], and cod (Gadus morhua) [13], etc. Even though QIM is fast and reliable in determining the freshness of seafood, it still requires experts to evaluate the quality attributes. Alternatively, appearance, odour, and taste can be measured by machine vision system (MVS), electronic nose (e-nose), and electronic tongue (e-tongue), respectively.Book Part Citation - WoS: 7Citation - Scopus: 8Impact of Irradiation on the Microbial Ecology of Foods(Wiley, 2016) Ünlütürk, Sevcan; Ünlütürk, SevcanBook Part Citation - Scopus: 11Organotin Compounds as Pvc Stabilizers(Wiley, 2008) Arkış, EsenWhen 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.