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Öğe Magnetite nanoparticles grafted with murexide-terminated polyamidoamine dendrimers for removal of lead (II) from aqueous solution: synthesis, characterization, adsorption and antimicrobial activity studies(Journals & Books, 2021-03) Ekinci, Selma; İlter, Zülfiye; Ercan, Selami; Çınar, Ercan; Çakmak, ReşitIn this study, new, efficient, eco-friendly and magnetically separable nanoadsorbents, MNPs-G1-Mu and MNPs-G2-Mu, were successfully prepared by covalently grafting murexide-terminated polyamidoamine dendrimers on 3-aminopropyl functionalized silica-coated magnetite nanoparticles, and used for rapid removal of lead (II) from aqueous medium. After each adsorption process, the supernatant was successfully acquired from reaction mixture by the magnetic separation, and then analyzed by employing ICP-OES. Chemical and physical characterizations of new nanomaterials were confirmed by XRD, FT-IR, SEM, TEM, and VSM. Maximum adsorption capacities (qm) of both prepared new nanostructured adsorbents were compared with each other and also with some other adsorbents. The kinetic data were appraised by using pseudo-first-order and pseudo-second-order kinetic models. Adsorption isotherms were found to be suitable with both Langmuir and Freundlich isotherm linear equations. The maximum adsorption capacities for MNPs-G1-Mu and MNPs-G2-Mu were calculated as 208.33 mg g−1 and 232.56 mg g−1, respectively. Antimicrobial activities of nanoparticles were also examined against various microorganisms by using microdilution method. It was determined that MNPs-G1-Mu, MNPs-G2-Mu and lead (II) adsorbed MNPs-G2-Mu showed good antimicrobial activity against S. aureus ATTC 29213 and C. Parapsilosis ATTC 22019. MNPs-G1-Mu also showed antimicrobial activity against C. albicans ATTC 10231.Öğe Electrochemical performance of boron-doped diamond electrode in surfactant-containing media for ambroxol determination(Elsevier, 2014-07-17) Levent, Abdulkadir; Yardım, Yavuz; Şentürk, ZühreA novel application of boron-doped diamond electrode is introduced for the determination of ambroxol, a potential antioxidant drug belonging to the expectorant class. The electrochemical oxidation of ambroxol was first investigated by cyclic voltammetry using boron-doped diamond and glassy carbon electrodes in aqueous solutions both with and without the addition of surfactant. The compound was irreversibly oxidized in one/two steps at high positive potentials, resulting in the formation of a couple with a reduction and re-oxidation wave at less positive potentials. Special attention was given to the use of adsorptive stripping voltammetry at a surface of mildly oxidized boron-doped diamond electrode in aqueous solutions over the pH range of 1.0–10.0. Addition of anionic surfactant (sodium dodecylsulfate) to ambroxol-containing electrolyte enhanced the stripping current signal. Using square-wave stripping mode, the drug yielded a well-defined voltammetric response in phosphate buffer pH 2.5 containing 4 × 10−4 M sodium dodecylsulfate at +1.02 V (versus Ag/AgCl) (after 30 s accumulation at +0.50 V). The process could be used to determine ambroxol in the concentration range of 0.05–0.7 μM, with a detection limit of 0.010 μM (4.2 ng mL−1). The suggested method was successfully applied to pharmaceuticals and spiked human urine samples.Öğe Ecomuseum, community museology, local distinctiveness, Hüsamettindere village, Bogatepe village, Turkey(Emerald, 2015-05-18) Doğan, MustafaPurpose – The concept of sustainable development is now widely accepted as a means of protecting natural resources and cultural heritage. One approach to ensuring sustainability, especially in relation to cultural tourism, is the ecomuseum. Turkey has considerable potential to develop ecomuseological models to encourage local sustainable development. The purpose of this paper is to explore the development of ecomuseums in Turkey by analysing the recent implementation of the concept in Hüsamettindere and Bogatepe villages. Current practices at these two sites are evaluated in comparison with the basic principles of ecomuseum theory. Design/methodology/approach – This paper explores local community involvement in two emerging ecomuseums in Turkey based on several years of participant action research by the author; it describes the nature of the two ecomuseums based on that experience. In addition an in-depth survey was carried out between February and April 2013 by Canakkale Onsekiz Mart University when 45 local participants were interviewed for their views on the ecomuseum developments, using the MACDAB method (Borrelli et al., 2008) as a guide. Findings – Even though the two implementations in Turkey have different features deriving from their local dynamics, they have had a similar experience in terms of the development process. Both began with a volunteer movement, the organisation of the local community, the formation of civil initiatives, a joint decision-making processes and the existence of participation and consensus. This process conforms to the basic principles of ecomuseology. The ecomuseums have also raised concerns about the loss of rural heritage and the mechanisms for conserving it within the model of the “living” ecomuseum. The most significant fact to emerge from this initial review of the two ecomuseums is that it is not necessarily their ability to conserve fragments of tangible and intangible heritage that is paramount in Turkey, but their importance in providing employment opportunities in rural areas. Originality/value – Ecomuseum movement is a very important and practical model for sustainable development and tourism. Ecomuseums can also be functional tools for protecting of cultural heritage and developing of local areas. Even though Turkey has got many cultural heritage sources, they are not used productively for local sustainable development. The two implementations will be sample to all natural and cultural heritage areas of Turkey for sustainable development.Öğe Thermal performance enhancement of flat-plate solar collectors by means of three different nanofluids(Elsevier, 2018-12) Budak Ziyadanoğulları, Neşe; Yıldız, Cengiz; Yücel, Halit LutfiSolar energy, which comes first among renewable energy sources, enables efficient use of energy with many applications due to its low operating cost and environmental friendliness. In this study, we experimentally investigated the effects on thermal efficiency of nanofluid and water as working fluids in flat-plate solar collector hot water solar energy systems. Nanofluids were prepared by adding Al2O3, CuO, and TiO2 nanoparticles at 0.2, 0.4, and 0.8 vol% into distilled water, and then the thermophysical properties (thermal conductivity, viscosity) of the prepared nanofluids were determined. Flow rate was adjusted to 250 l/h at given concentrations for each nanofluid in the experimental setups and data such as collector inlet and outlet temperatures, ambient and tap water temperatures; radiation, humidity, and wind speed were measured and recorded. The obtained data were used to calculate efficiencies according to ASHRAE 93-2003 standards. When compared with water, the results indicated that the use of nanofluid increased collector efficiency.Öğe Interactive goal programming algorithm with Taylor series and interval type 2 fuzzy numbers(Springer Nature, 2019-06-01) Dalman, Hasan; Bayram, MustafaThis paper presents an interactive fuzzy goal programming (FGP) approach for solving Multiobjective Nonlinear Programming Problems (MONLPP) with interval type 2 fuzzy numbers (IT2 FNs). The cost and time of the objective functions, and the requirements of each kind of resources are taken to be trapezoidal IT2 FNs. Here, the considered fuzzy problem is first transformed into an equivalent crisp MONLPP, and then the MONLPP is converted into an equivalent multiobjective linear programming problem (MOLPP). By using an algorithm based on Taylor series, this problem is also reduced into a single objective linear programming problem (LPP) which can be easily solved by Maple 2017 optimization toolbox. Finally, the proposed solution procedure is illustrated by a numerical example.Öğe Novel C2-symmetric macrocycles bearing diamide-diester groups: Synthesis and enantiomeric recognition for primary alkyl ammonium salts(American Chemical Society, 2008-03-12) Sünkür, Murat; Barış Cebe, Deniz; Hoşgören, Halil; Toğrul, MahmutWe synthesized a series of novel macrocycles with diamide−diester groups (S,S)-1, (S,S)-2, (S,S)-3, and (R,R)-1, derived from dimethyloxalate and amino alcohols by high dilution technique, and evaluated enantiomeric recognition properties of these macrocycles toward primary alkyl ammonium salts by 1H NMR titration. Taking into account the host employed, important differences were observed in the Ka values of (R)-Am and (S)-Am for (S,S)-1 and (R,R)-1 hosts, KS/KR = 5.55 and KR/KS = 3.65, ΔΔGo = 0.43 and −0.32 kJ mol-1, respectively. There seems a general tendency for the host to include the guests with the same absolute configuration.Öğe Ecological ideals, sustainable tourism and the heritage concept of an eco-village: The case of Arcosanti, USA(Taylor and Francis Ltd., 2019) Doğan, MustafaArcosanti in Arizona, USA, is a yet-to-be completed ecological settlement which reflects the major ideas of Paolo Soleri, an Italian architect and philosopher, on an alternative type of city. Based on field research using interviews, participatory observation and the survey method it examines the relationship between tourism and eco-settlements, using Arcosanti as a case study, in order to discuss current approaches to sustainable tourism and to examine visitor profiles, perceptions, and attitudes. The data indicates that ecological settlements such as Arcosanti can be an attractive tourist destination and it is clear that although Arcosanti had started life as an urban experiment based on ecological and alternative ideas, today it is a place that attracts many visitors. Regardless of whether Arcosanti can be categorized as an eco-village or eco-city, its valuable attractiveness results from Paolo Soleri and his tangible/intangible heritage that contributes an income via sustainable tourism. The study concludes that Arcosanti is an excellent case which offers the promise that ecological settlements can have significant potential for sustainable tourism.Öğe Ecological ideals, sustainable tourism and the heritage concept of an eco-village: the case of Arcosanti, USA(Taylor & Francis, 2019-07-04) Doğan, MustafaArcosanti in Arizona, USA, is a yet-to-be completed ecological settlement which reflects the major ideas of Paolo Soleri, an Italian architect and philosopher, on an alternative type of city. Based on field research using interviews, participatory observation and the survey method it examines the relationship between tourism and eco-settlements, using Arcosanti as a case study, in order to discuss current approaches to sustainable tourism and to examine visitor profiles, perceptions, and attitudes. The data indicates that ecological settlements such as Arcosanti can be an attractive tourist destination and it is clear that although Arcosanti had started life as an urban experiment based on ecological and alternative ideas, today it is a place that attracts many visitors. Regardless of whether Arcosanti can be categorized as an eco-village or eco-city, its valuable attractiveness results from Paolo Soleri and his tangible/intangible heritage that contributes an income via sustainable tourism. The study concludes that Arcosanti is an excellent case which offers the promise that ecological settlements can have significant potential for sustainable tourism.
