PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collections

Permanent URI for this collectionhttps://hdl.handle.net/20.500.13091/5

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Now showing 1 - 20 of 32

Citation - WoS: 25
Citation - Scopus: 29
Aerogels as Promising Materials for Antibacterial Applications: a Mini-Review
(ROYAL SOC CHEMISTRY, 2021) Kaya Güzel, Gülcihan; Aznar, Elena; Deveci, Hüseyin; Martinez-Manez, Ramon
The increasing cases of bacterial infections originating from resistant bacteria are a serious problem globally and many approaches have been developed for different purposes to treat bacterial infections. Aerogels are a novel class of smart porous materials composed of three-dimensional networks. Recently, aerogels with the advantages of ultra-low density, high porosity, tunable particle and pore sizes, and biocompatibility have been regarded as promising carriers for the design of delivery systems. Recently, aerogels have also been provided with antibacterial activity through loading of antibacterial agents, incorporation of metal/metal oxides and via surface functionalization and coating with various functional groups. In this mini-review, the synthesis of aerogels from both conventional and low-cost precursors is reported and examples of aerogels displaying antibacterial properties are summarized. As a result, it is clear that the encouraging antibacterial performance of aerogels promotes their use in many antibacterial applications, especially in the food industry, pharmaceutics and medicine.
Citation - WoS: 18
Citation - Scopus: 19
Antibacterial Activity of Linezolid Against Gram-Negative Bacteria: Utilization of Epsilon-Poly Capped Silica Xerogel as an Activating Carrier
(MDPI, 2020) Kaya Güzel, Gülcihan; Medaglia, Serena; Candela-Noguera, Vicente; Tormo-Mas, Maria Angeles; Marcos, Maria Dolores; Aznar, Elena; Martinez-Manez, Ramon
In recent times, many approaches have been developed against drug resistant Gram-negative bacteria. However, low-cost high effective materials which could broaden the spectrum of antibiotics are still needed. In this study, enhancement of linezolid spectrum, normally active against Gram-positive bacteria, was aimed for Gram-negative bacteria growth inhibition. For this purpose, a silica xerogel prepared from a low-cost precursor is used as a drug carrier owing to the advantages of its mesoporous structure, suitable pore and particle size and ultralow density. The silica xerogel is loaded with linezolid and capped with epsilon-poly-l-lysine. The developed nano-formulation shows a marked antibacterial activity against to Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. In comparison to free linezolid and epsilon-poly-l-lysine, the material demonstrates a synergistic effect on killing for the three tested bacteria. The results show that silica xerogels can be used as a potential drug carrier and activity enhancer. This strategy could provide the improvement of antibacterial activity spectrum of antibacterial agents like linezolid and could represent a powerful alternative to overcome antibiotic resistance in a near future.
Citation - WoS: 5
Citation - Scopus: 6
Appraisal of Inorganic and Lignocellulosic Organic Shell Wastes as a Green Filler in Epoxy-Based Hybrid Composites
(Elsevier, 2025) Ahmetli, Gulnare; Kocaman, Suheyla; Soydal, Ulku; Kocak, Beril; Ozmeral, Nimet; Musayev, Nijat
Hybrid composites are now becoming increasingly important regarding economic and ecological compatibility. This study presented the research results that evaluate the feasibility of using cherry pit shell (CPSh) and chicken eggshell (ChESh) natural wastes as a new hybrid filler mixture for the first time. CPSh and ChESh can reduce the composite material cost and increase the biobased content. CPSh was treated with a 5 % NaOH alkali solution to enhance the lignocellulosic filler-matrix interfacial interaction. Hybrid green organic and inorganic fillers were used in the epoxy matrix (ER). Morphological, water absorption, thermal, and mechanical performance of hybrid composites were investigated. The tensile strength of ER increased max. by 5.73, 7.3, 17.98, and 14.27 % in the case of raw CPSh, ChESh, and hybrid filler mixtures at 1:1 and 1:3 wt mixing ratios of alkali-treated CPSh (NaOHCPSh) and ChESh, respectively. The composites' thermal stability and dynamic-mechanical properties in different aging environments (seawater and hydrothermal) were examined by thermogravimetric analysis (TGA) and dynamic-mechanical analysis (DMA). Hydrothermal was the most affected aging condition on the composite properties. In addition, ANOVA is applied to find the significant effect of different weight percentages of hybrid fillers on the mechanical properties of composites.
Citation - WoS: 37
Citation - Scopus: 47
Behaviour of Waste Polypropylene Pyrolysis Char-Based Epoxy Composite Materials
(SPRINGER HEIDELBERG, 2020) Soğancıoğlu, Merve; Yel, Esra; Ahmetli, Gülnare
In this study, polypropylene (PP) plastic wastes were pyrolysed. Solid pyrolysis product (char) was used as filler material for the preparation of epoxy composite. 300, 400, 500, 600 and 700 degrees C were selected as final pyrolysis temperatures. Solid pyrolysis product (char) was analysed by elemental, FTIR, SEM, BET and TGA analysis. The epoxy composite samples were prepared with char obtained from pyrolysis. Mechanical properties of composites were analysed by hardness, tensile strength, elongation at break, electrical conductivity tests to explain the effects of pyrolysis temperature and char doses over composite properties. Thermogravimetric properties of composites were determined by TGA analyses. The water absorption behaviour of composite samples was determined by water adsorption test. Epoxy composite produced from PP char obtained under 300 degrees C showed the most ideal behaviour.
Citation - WoS: 44
Citation - Scopus: 47
Biosorption of Methylene Blue and Malachite Green on Biodegradable Magnetic Cortaderia Selloana Flower Spikes: Modeling and Equilibrium Study
(TAYLOR & FRANCIS INC, 2021) Parlayıcı, Şerife; Pehlivan, Erol
This study involves the production of a novel biosorbent obtained fromCortaderia selloanaflower spikes (CSFs). MagneticC. selloanaflower spikes (nM infinity CSFs) was applied as an ideal biosorbent for the elimination of dyes from water. They were utilized for the removal from aqueous solutions of malachite green (MG) and methylene blue (MB) dyes. The analyses of the equilibrium were done under certain experimental parameters such as contact time, initial dye concentration, pH, and quantity of biosorbent. The rapid intake of dyes to reach the equilibrium in a short period time showed the effectiveness of nM infinity CSFs to adsorb MG and MB. The experimental information of MB and MG was obtained from the Langmuir model and it confirmed the magnificent dye biosorption ability; 72.99 mg/g for CSFs/MB, 119.05 mg/g for nM infinity CSFs/MB, 31.06 mg/g for CSFs/MG, and 56.50 mg/g for nM infinity CSFs/MG. Langmuir's model affirmed the excellent dye biosorption ability. The pseudo-second-order kinetic model displayed a great fit to the experimental result for the removal of MG and MB. The nM infinity CSFs compared with raw biosorbent affirmed that the magnetic form of the biosorbent has a greater removal ability for MB and MG. nM infinity CSFs is a noteworthy biosorbent for MB and MG removal from wastewater. [GRAPHICS] HIGHLIGHTS Magnetic Cortaderia selloana flower spikes (nM1CSFs) was synthesized for the biosorption of dyes FT-IR and SEM analysis were used for characterization. The Langmuir isotherm model fitted the data of the adsorption for nM1CSFs nM1CSFs is a noteworthy biosorbent for MB and MG removal from wastewater.
Citation - WoS: 11
Citation - Scopus: 9
Capture and Release Recyclable Dimethylaminomethyl-Calixarene Functional Cloths for Point-Of Removal of Highly Toxic Chromium Water Pollutants
(AMER CHEMICAL SOC, 2020) Bieber, Vera S.; Özçelik, Egemen; Cox, Harrison J.; Ottley, Christopher J.; Ratan, Jatinder K.; Karaman, Mustafa; Badyal, Jas Pal S.
Chromium(VI) contamination of drinking water arises from industrial activity wherever there is a lack of environmental legislation enforcement regarding the removal of such pollutants. Although it is possible to remove such harmful metal ions from drinking water through large-scale facilities, there currently exists no safe and simple way to filter chromium(VI) oxoanions at the point of use (which is potentially safer and necessary in remote locations or humanitarian scenarios). High-surface-area cloth substrates have been functionalized with calixarene molecules for the selective capture of aqueous chromium(VI) oxoanions in the presence of structurally similar anions. This is accomplished by pulsed plasmachemical deposition of a linker layer and subsequent functionalization with dimethylaminomethyl-calixarene (5,11,17,23-tetrakis [(dimethylamino)methyl]-25,26,27,28-tetrahydroxycalix[4]arene. Chromium(VI) oxoanions are captured by simply passing polluted water through the functionalized cloth, while other ions not harmful/beneficial to human health remain in the water. These cloth filters are simple to use, highly selective, and easily recyclable-thus making them attractive for point-of-use application in geographic regions lacking appropriate wastewater treatment plants or flawed environmental monitoring systems. Chromium(VI) pollutants have been successfully removed from real-world contaminated industrial wastewater streams using the dimethylaminomethyl-calixarene functionalized cloths.
Citation - WoS: 2
Citation - Scopus: 2
Chitosan-Coated Black Sesame (sesamum Indicum L.) Seed Pulp as a Novel Candidate Adsorbent for Cr(vi) Elimination
(IWA PUBLISHING, 2019) Parlayıcı, Şerife; Tuna, Kübra; Özdemir, Elif; Pehlivan, Erol
This study evaluates the application of Cr(VI) adsorption from the prepared synthetic solution by black sesame (Sesamum indicum L.) seed pulp (BSSP) and chitosan (Cts)-coated black sesame seed pulp beads (Cts-BSSP). BSSP and Cts-BSSP were used as an adsorbent without any chemical or physical treatment to remove Cr(VI) from an aqueous medium. The results indicated that the Cr(VI) removal was pH-dependent and reached an optimum at pH 2.0. It has been observed that the percentage of adsorption increased from 62% to 95% when the amount of Cts-BSSP increased from 0.0125 g to 0.0250 g. The required adsorbent amount for the maximum removal was 0.05 g and 0.1 g for Cst-BSSP and BSSP, respectively. The contact time for the adsorption was 120 min and 90 min for BSSP and Cst-BSSP, respectively. Scanning electron microscopy and Fourier transform infrared spectroscopy were used to explore the possible adsorption mechanism for Cr(VI). The equilibrium data for the BSSP and Cts-BSSP were used with the Langmuir and Freundlich adsorption isotherm models to assess the adsorption capacity and relevant mechanism. The adsorption capacity of the Cts-BSSP for Cr(VI) is relatively high compared to BSSP. The monolayer maximum adsorption capacities for Cr(VI) ions were 31.44 and 18.32 mg/g for Cts-BSSP and BSSP, respectively.
Citation - WoS: 22
Citation - Scopus: 24
Decolorization of Water Through Removal of Methylene Blue and Malachite Green on Biodegradable Magnetic Bauhinia Variagata Fruits
(TAYLOR & FRANCIS INC, 2022) Bayram, Okan; Köksal, Elif; Göde, Fethiye; Pehlivan, Erol
Batch sorption experiments were performed to investigate the potential of Bauhinia variagata fruit (BVf) and nano-magnetic Bauhinia variagata fruit (nM-BVf) to remove methylene blue (MB) and malachite green (MG). Equilibrium studies have been carried out using various experimental parameters such as the amount of biosorbent, initial solution concentration, contact time, pH, and temperature. The Langmuir, Freundlich, Scatchard, D-R and Temkin adsorption models were applied for the experimental information of MB and MG. The Freundlich model fits better than the Langmuir model. Freundlich model confirmed the magnificent dye sorption ability; 19.3 mg/g for BVf/MB, 21.2 mg/g for nM-BVf/MB, 19.7 mg/g for BVf/MG, and 30.1 mg/g for nM-BVf/MG. The pseudo-second-order kinetic model displayed a more suitable behavior to the experimental result for the removal of MG and MB. Thermodynamic parameters such as changes in Gibbs free energy (Delta G(o)), enthalpy (Delta H-o), and entropy (Delta S-o) were investigated and the fine details in the adsorption system were completed. The conclusion from this study is that the prepared nano biosorbent can be efficient for the removal of cationic dyes from wastewater.
Citation - WoS: 18
Citation - Scopus: 19
Development of Highly Luminescent Water-Insoluble Carbon Dots by Using Calix[4]pyrrole as the Carbon Precursor and Their Potential Application in Organic Solar Cells
(Amer Chemical Soc, 2022) Coşkun, Yağız; Ünlü, Fatma Yelda; Yılmaz, Tuğbahan; Türker, Yurdanur; Aydoğan, Abdullah; Kuş, Mahmut; Ünlü, Caner
Carbon dots (CDs) are carbon-based fluorescent nanomaterials that are of interest in different research areas due to their low cost production and low toxicity. Considering their unique photophysical properties, hydrophobic/amphiphilic CDs are powerful alternatives to metal-based quantum dots in LED and photovoltaic cell designs. On the other hand, CDs possess a considerably high amount of surface defects that give rise to two significant drawbacks: (1) causing decrease in quantum yield (QY), a crucial drawback that limits their utilization in LEDs, and (2) affecting the efficiency of charge transfer, a significant factor that limits the use of CDs in photovoltaic cells. In this study, we synthesized highly luminescent, water-insoluble, slightly amphiphilic CDs by using a macrocyclic compound, calix[4]pyrrole, for the first time in the literature. Calix[4]pyrrole-derived CDs (CP-DOTs) were highly luminescent with a QY of over 60% and size of around 4-10 nm with graphitic structure. The high quantum yield of CP-DOTs indicated that they had less amount of surface defects. Furthermore, CP-DOTs were used as an additive in the active layer of organic solar cells (OSC). The photovoltaic parameters of OSCs improved upon addition of CDs. Our results indicated that calix[4]pyrrole is an excellent carbon precursor to synthesize highly luminescent and water-insoluble carbon dots, and CDs derived from calix[4]pyrrole are excellent candidates to improve optoelectronic devices.
Citation - WoS: 28
Citation - Scopus: 31
Fast Decolorization of Cationic Dyes by Nano-Scale Zero Valent Iron Immobilized in Sycamore Tree Seed Pod Fibers: Kinetics and Modelling Study
(TAYLOR & FRANCIS INC, 2019) Parlayıcı, Şerife; Pehlivan, Erol
In the present work, Sycamore (Platanus occidentalis) tree seed pod fibers (STSPF) and nano-scale zero valent iron particles (nZVI) immobilized in Sycamore tree seed pod fibers (nZVIx298;STSPF) were produced. This biosorbent has been utilized as a viable effective biosorbent in the removing of methylene blue hydrate (MB), malachite green oxalate(MG), methyl violet 2B(MV) dyes from synthetic wastewater. The biosorbents were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Various parameters such as contact time, solution concentration, pH and amount of biosorbent were investigated in order to evaluate the potential of the nanomaterials immobilized on natural wastes as sorbing biomaterials for the cationic dyes. Study on sorption kinetic and the sorption isotherm was carried out and best fitting models for the rate kinetics and isotherms were suggested. Langmuir isotherm was observed to be compatible with the isotherm models. The STSPF in the raw form showed the best dye sorption capacity of 43.67 mg/g for MG, 25.32 mg/g for MV, and 126.60 mg/g for MB. The magnetic nZVIx298;STSPF showed the best dye sorption capacity 92.59 mg/g for MG, 92.59 mg/g for MV, and 140.80 mg/g for MB. The iron nanoparticles immobilized biosorbent exhibited a higher removal capacity for all dyes compared to the raw biosorbent. [GRAPHICS] .
Citation - WoS: 8
Citation - Scopus: 7
Fluorescence Switchable Sensor Enabled by a Calix[4]arene-Cu(ii) Complex System for Selective Determination of Itraconazole in Human Serum and Aqueous Solution
(Elsevier, 2022) Akceylan, Ezgi; Erdemir, Serkan; Tabakçı, Mustafa; Sivrikaya, Abdullah; Tabakçı, Begüm
A switchable fluorescence sensor based on a calix (Monapathi et al., 2021) [4]arene:Cu2+ complex (FLCX/Cu) has been developed for the detection of itraconazole (ITZ) with high sensitivity and specificity. For the devel-opment of the sensor, the selective complexation of a fluorescent calix (Monapathi et al., 2021) [4]arene de-rivative (FL-CX) with the Cu2+ ion causing fluorescence quenching was utilized. In addition, the sensor properties of the FLCX/Cu prepared were investigated. For this purpose, various substances (selected anions, cations, and drugs) with which ITZ can be found together were studied in an aqueous solution. Limit of detection (LOD) and limit of quantification (LOQ) values were determined in the range of 1.00-60.0 mu g/L as 3.34 mu g/L and 11.1 mu g/L for ITZ, respectively. Moreover, the real sample analyses were performed in human serum and tablet form. Furthermore, the effect of some possible serum contents on sensor performance was also studied. All these studies confirmed the development of a simple, precise, accurate, reproducible, highly sensitive, and very stable fluorescence sensor.
Citation - WoS: 22
Citation - Scopus: 23
A Green Approach To Modify Surface Properties of Polyurethane Foam for Enhanced Oil Absorption
(MDPI, 2020) Ng, Zhi Chien; Roslan, Rosyiela Azwa; Lau, Woei Jye; Gürsoy, Mehmet; Karaman, Mustafa; Jullok, Nora; Ismail, Ahmad Fauzi
The non-selective property of conventional polyurethane (PU) foam tends to lower its oil absorption efficiency. To address this issue, we modified the surface properties of PU foam using a rapid solvent-free surface functionalization approach based on the chemical vapor deposition (CVD) method to establish an extremely thin yet uniform coating layer to improve foam performance. The PU foam was respectively functionalized using different monomers, i.e., perfluorodecyl acrylate (PFDA), 2,2,3,4,4,4-hexafluorobutyl acrylate (HFBA), and hexamethyldisiloxane (HMDSO), and the effect of deposition times (1, 5 and 10 min) on the properties of foam was investigated. The results showed that all the modified foams demonstrated a much higher water contact angle (i.e., greater hydrophobicity) and greater absorption capacities compared to the control PU foam. This is due to the presence of specific functional groups, e.g., fluorine (F) and silane (Si) in the modified PU foams. Of all, the PU/PHFBA(i)foam exhibited the highest absorption capacities, recording 66.68, 58.15, 53.70, and 58.38 g/g for chloroform, acetone, cyclohexane, and edible oil, respectively. These values were 39.19-119.31% higher than that of control foam. The promising performance of the PU/PHFBA(i)foam is due to the improved surface hydrophobicity attributed to the original perfluoroalkyl moieties of the HFBA monomer. The PU/PHFBA(i)foam also demonstrated a much more stable absorption performance compared to the control foam when both samples were reused for up to 10 cycles. This clearly indicates the positive impact of the proposed functionalization method in improving PU properties for oil absorption processes.
Isolation and Characterization of Chemical Constituents From Chaerophyllum Bulbosum Roots and Their Enzyme Inhibitory and Antioxidant Effects
(Walter De Gruyter Gmbh, 2022) Tel-Çayan, Gülşen; Deveci, Ebru; Molo, Zeynep; Duru, Mehmet Emin; Öztürk, Mehmet
Isolation and bioactive effects of the roots of Chaerophyllum bulbosum L. were firstly investigated herein. Enzyme (acetylcholinesterase, butyrylcholinesterase, urease, alpha-amylase, alpha-glucosidase, and tyrosinase) inhibitory effects of C. bulbosum root extracts were tested. Three known compounds, n-heptadecanyl eicosanoate (1), stigmasterol (2), and beta-sitosterol-3-O-beta-d-glucopyranoside (3) were isolated from C. bulbosum. Antioxidant and enzyme inhibitory effects of isolated compounds were investigated. The hexane extract (IC50: 349.58 +/- 0.06 mu g/mL) displayed a higher alpha-glucosidase inhibitory effect than the standard (IC50: 378.66 +/- 0.14 mu g/mL). The best inhibitory effect was found in compound 2 on AChE (46.40 +/- 0.31%), BChE (56.41 +/- 0.54%), and urease (92.47 +/- 0.11%); compound 1 on alpha-amylase (22.27 +/- 0.61%); and compound 3 on alpha-glucosidase (12.43 +/- 0.25%) and tyrosinase (19.00 +/- 0.16%). All isolated compounds showed moderate antioxidant effects in all assays. This study contributes to the therapeutic uses of Chaerophyllum roots and emphasizes the value of C. bulbosum species for the development of novel therapeutic agents.
Citation - WoS: 25
Citation - Scopus: 30
Isolation, Structural Characterization, and Biological Activities of Galactomannans From Rhizopogon Luteolus and Ganoderma Adspersum Mushrooms
(ELSEVIER, 2020) Çayan, Gülsen Tel; Muhammad, Akhtar; Deveci, Ebru; Duru, Mehmet Emin; Öztürk, Mehmet
Polysaccharides are essential compounds that contribute to the biological activities of mushrooms. Two new galactomannans (Galactomannan I and II) were isolated from R. luteolus and G. adspersum. Their structures were characterized using FT-IR, 1D, and 2D-NMR techniques. Both isolated galactomannans I and II mainly include D-mannose and D-galactose in the molar percentages of 0.81:1.0 and 1:1.4, respectively. The GPC calculation demonstrated that the molecular weights are about 5240 and 5090 Da, respectively. Their structures comprise of beta-(1,4)-mannose (Man) backbone units with alpha-(1,6)-galactose (Gal) single unit as a side group. The anticholinesterase activity of galactomannans was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), spectrophotometrically. Antioxidant activity was also measured by six assays (ABTS(center dot+), DPPH center dot, O-2(center dot-), beta-carotene-linoleic acid, metal chelating, and CUPRAC assays). Galactomannan II indicated close inhibitory activity to galantamine against AChE (61.04 +/- 0.45%) and BChE (59.70 +/- 1.15%) at 50 mu g/mL concentration. Nevertheless, both galactomannans showed low antioxidant activity in all tests. This study reveals that mainly, Galactomannan II could be used as a new natural promising anticholinesterase agent. (C) 2020 Elsevier B.V. All rights reserved.
Citation - WoS: 15
Citation - Scopus: 20
Modified Peach Stone Shell Powder for the Removal of Cr (vi) From Aqueous Solution: Synthesis, Kinetic, Thermodynamic, and Modeling Study
(TAYLOR & FRANCIS INC, 2019) Parlayıcı, Şerife
Citric acid treated peach (Prunus persica) stone shell as an effective adsorbent were synthesized for the adsorption of Cr (VI) from aqueous solutions. The aim of this study was to predict the optimal conditions for citric acid modification of peach kernel shell (CA-PSS) the modification process and the removal of Cr (VI) ions from aqueous solutions using a batch-type model. Research of its adsorption of Cr (VI) showed that CA-PSS in conditions at 120 degrees C for 4 h and in mass ratio of peach stone shell: citric acid =1:1 had greater adsorption capacity. Cr (VI) adsorption was investigated by changing several conditions. Adsorption studies have been carried out to determine the effect of time, pH, adsorbent dosage, temperature, and initial Cr (VI) ions concentration on the adsorption capacity of Cr (VI) ions by the esterified peach stone shell. The results indicate that the Langmuir model provides a better fit for the adsorption data. The equilibrium adsorption capacity of Cr (VI) was 25.71 mg/g for CA-PSS. The adsorption kinetic process followed the pseudo-second-order kinetics. Thermodynamic parameters such as the changes in Delta G degrees, Delta H degrees, and Delta S degrees have also been estimated, and the process was found to be spontaneous.
Citation - WoS: 16
Citation - Scopus: 17
Nano-Scale Selective and Sensitive Optical Sensor for Metronidazole Based on Fluorescence Quenching: 1h-Phenanthro[9,10 Fluorescent Probe
(ELSEVIER, 2021) Şimşir, Evin Ayşegül; Erdemir, Serkan; Tabakcı, Mustafa; Tabakcı, Begüm
It is crucial to determine and control the metronidazole (MET) ingredient in food and pharmaceuticals for human health and food safety. Even though many sensors have been previously reported to detect MET, there is still a need for a highly selective and sensitive, easy, fast, cost-effective sensor in this area. Herein, we report a fluorescent calix[4]arene derivative (PIMC) for highly selective and sensitive and facile and rapid MET detection based on fluorescence (FL) quenching. The highest FL quenching occurs when PIMC is exposed to MET solution at 400 nm (lambda(ex) = 340). Owing to the quenching efficacy of MET linearly up to 5.5 x 10(4) nM was obtained a detection limit of 2.44 nM. Besides, interferences of other pharmaceuticals and ions on probe performance were investigated. The FL probe was successful in MET detection without the assistance of any separation techniques in a pharmaceutical sample (tablet) with an acceptable recovery of 101.3%. The applicability of the current probe as a paper-based sensor to MET detection has been successfully tested. As a result, the proposed probe presents a fast and suitable strategy to sensitive and selective detect MET and proves a good potential for practical applications, especially pharmaceutical preparations. (C) 2021 Elsevier B.V. All rights reserved.
Citation - WoS: 38
Citation - Scopus: 39
A Novel Polyaniline/Nio Nanocomposite as a Uv and Visible-Light Photocatalyst for Complete Degradation of the Model Dyes and the Real Textile Wastewater
(SPRINGER HEIDELBERG, 2021) Haspulat Taymaz, Bircan; Eskizeybek, Volkan; Kamış, Handan
The textile processing industry utilizes enormous amounts of water. After the dying process, the wastewater discharged to the environment contains carcinogens, non-biodegradable, toxic, and colored organic materials. This study aimed to develop a nanocomposite material with improved photocatalytic activity to degrade textile dyes and without a need for a post-separation process after the use. For this, nickel oxide nanoparticles (NiO NPs) were synthesized by a simple method in aqueous media. Then, NiO-doped polyaniline (PANI/NiO) with efficient absorption in the visible region (optical band gap of 2.08 eV) synthesized on a stainless steel substrate with electropolymerization of aniline in the aqueous media. The photocatalytic activity of PANI/NiO film was also investigated by the degradation of model dyes. Under UV and visible light irradiation, the PANI/NiO film degraded methylene blue and rhodamine B dyes entirely in 30 min. Moreover, the PANI/NiO film was also utilized to degrade real textile wastewater (RTW) without applying any pre-process; it was entirely decomposed by the nanocomposite film in only 45 min under UV light irradiation. The photocatalytic reaction rate of the pure PANI film is increased as 2.5 and 1.5 times with the addition of NiO NPs under UV and visible light irradiations for degradation RTW, respectively. The photocatalytic efficiency was attributed to reduced electron-hole pair recombination on the photocatalyst surface. Furthermore, the photocatalytic stability is discussed based on re-use experiments. The photocatalytic performance remains nearly unchanged, and the degradation of dyes is kept 94% after five cycles.
Citation - WoS: 33
Citation - Scopus: 31
One Novel Calix[4]arene Based Qcm Sensor for Sensitive, Selective and High Performance-Sensing of Formaldehyde at Room Temperature
(ELSEVIER, 2020) Temel, Farabi
This work designs the synthesis of a novel amino morpholine schiff base functionalized calix[4]arene cage (SCC), its deposition onto Quartz Crystal Microbalance (QCM) crystal surface, and usage for the selective detecting of formaldehyde (HCHO). The SCC modified QCM sensor has been characterized by contact angle measurements and microscopy images. Initial experiments revealed that the frequency response decreased significantly which means that there was a good interaction between the SCC molecules and HCHO. The proposed sensor exhibited a linear response towards HCHO in different concentrations ranging from 1.85 to 9.25 ppm, having the high sensitivity (S) and low limit of detection (LOD) being 18.324 Hz/ppm and 0.67 ppm, respectively. Furthermore, the adsorption behavior and mechanism of HCHO onto the QCM sensor were investigated for this sensing system and the adsorption data exhibited a good correlation with the Freundlich and Langmuir-Freundlich adsorption models in terms of the regression coefficient. The QCM sensor showed outstanding selective performance to HCHO among %97 RH and some a number of interfering volatile organic compounds (VOCs) such as chloroform, dichloromethane, acetone, n-hexane, methanol, xylene, and ammonia. Thus, real-time, sensitive, selective and effective recognition of HCHO by the sensor can be explained some adsorption mechanisms such as size-fit concept, three-dimensional structures of molecules and interaction between moieties of the sensible film layer and analyte molecules such as hydrogen bonding interactions.
Citation - WoS: 6
Citation - Scopus: 8
Pan-Based Activated Carbon Nanofiber/Metal Oxide Composites for Co2 and Ch4 Adsorption: Influence of Metal Oxide
(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2021) Kırbıyık Kurukavak, Çisem; Büyükbekar, Burak Zafer; Ersöz, Mustafa
In the present study, we successfully prepared two different electrospun polyacrylonitrile (PAN) based-activated carbon nanofiber (ACNF) composites by incorporation of well-distributed Fe2O3 and Co3O4, nanoparticles (NPs). The influence of metal oxide on the structural, morphological, and textural properties of final composites was thoroughly investigated. The results showed that the morphological and textural properties could be easily tuned by changing the metal oxide NPs. Even though, the ACNE composites were not chemically activated by any activation agent, they presented relatively high surface areas (S-BET) calculated by Brunauer-Emmett-Thller (BET) equation as 212.21 and 185.12 m(2)/g for ACNE/Fe2O3 and ACNF/Co3O4 composites, respectively. Furthermore, the ACNE composites were utilized as candidate adsorbents for CO2 and CH4 adsorption. The ACNF/Fe2O3 and ACNF/Co3O4 composites resulted the highest CO2 adsorption capacities of 1.502 and 2.166 mmol/g at 0 degrees C, respectively, whereas the highest CH4 adsorption capacities were obtained to be 0.516 and 0.661 mmol/g at 0 degrees C by ACNF/Fe2O3 and ACNE/Co3O4 composites, respectively. The isosteric heats calculated lower than 80 kJ/mol showed that the adsorption processes of CO2 and CH4 were mainly dominated by physical adsorption for both ACNE composites. Our findings indicated that ACNF-metal oxide composites are useful materials for designing of CO2 and CH4 adsorption systems.
Citation - WoS: 35
Citation - Scopus: 37
Performance of Sio2/Ag Core/Shell Particles in Sonocatalalytic Degradation of Rhodamine B
(ELSEVIER SCIENCE BV, 2019) Deveci, İlyas; Mercimek, Bedrettin
In this study, SiO2/Ag Core/Shell nanoparticles was prepared and sonocatalytic activity of prepared catalyst was investigated by using Rhodamine B as model contaminant, at 35 kHz using ultrasonic power of 160 W within 90 min. The change in efficiency in the sonocatalytic degradation of Rhodamine B catalyzed by SiO2/Ag Core/Shell nanoparticles with respect to the initial concentration of dye, catalyst amount and temperature were firstly investigated. Optimal conditions were found as follows: catalyst amount = 15 mg/L, Temperature = 25 degrees C and initial concentration of dye = 10 ppm. Influence factors such as pH of solution, O-2 saturation of solution and the concentration of H2O2 added to the solution, on degradation efficiency in presence of catalyst, were investigated. SiO2/Ag Core/Shell nanoparticles showed higher sonocatalytic activity at pH = 7 with respect to acidic and alkaline conditions. Degradation efficiency was reached up to 67% in experiments which air pumped (0.6 L/min) through the solution with in 90 min. It was observed that the dye removal increased via increase while H2O2 concentration lower than 10 mM. Higher concentration of H2O2 than the optimal concentration had adverse effect on degradation efficiency. Our results showed that the SiO2/Ag Core/Shell nanoparticles were active catalyst for sonocatalytic degradation of dyes. Reusability of the catalyst was investigated.

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