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Thermal and Optical Properties of In and In2O3 Nanoparticles Synthesized Using Pulsed Plasma in Water

Emil ÖMÜRZAK

Article | 2018 | Physica Status Solidi (A) – Applications and Materials Science215 ( 11 )

We present small indium (In) nanoparticles with an average diameter of 4.5 nm synthesized by pulsed plasma in water. Slightly increased lattice constants and thermal stability of the tetragonal In are revealed by X‐ray diffraction analysis, Rietveld refinement, and thermogravimetric analysis. The highly crystalline body‐centered cubic indium oxide (In2O3) nanoparticles with an average diameter of 12 nm and various shapes (semispherical, semihexagonal, and semicubic) are obtained by annealing the as‐synthesized In nanoparticles at 450 °C. The bandgap energy of the In2O3 nanoparticles is 3.63 eV; the value is 25?igher than that of bul . . .k In2O3 and comparable to those of In2O3 nanoparticles/thin films prepared by other methods, despite their smaller siz More less

The efficiency of cationic-based hydrogels in heavy metal removal from wastewater

Bakıt BORKOYEV | Kalıypa SALİYEVA

Article | 2023 | Polymer Bulletin ( Published online: 21 November 2023 )

The present study draws attention to arsenic (V) (As(V)), chromium (III) (Cr(III)), and chromium (VI) (Cr(VI)) heavy metal pollutants, which have negative effects on aquatic ecosystems and indirectly pose a serious threat to the health of living things in the environment. Homopolymer and copolymer hydrogels were synthesized by the UV polymerization technique using 2-acrylamido-2-methyl-1-propansulfonic acid sodium salt (AMPS) and 3-acrlylamidopropil-trimethyl ammonium chloride monomers, and a crosslinker aimed to improve the swelling properties and metal sorption of the prepared hydrogels. The swelling balance values of hydrogels we . . .re determined by the gravimetric method in deionized water and different pH values, and their structural characterizations were carried out by Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA) techniques. Sorption efficiencies and sorption capacities of the synthesized hydrogels were determined using aqueous solutions containing As(V), Cr(III), and Cr(VI) heavy metal ions at 25 °C. It was determined that there was a significant increase in p(AMPS) (AM1)-based hydrogel's balance swelling value in deionized water compared to p(AP1) and p(AMPS-co-APTMACl) (AMAP1)-based hydrogels. The lowest equilibrium swelling value was reached in the AMAP1 hydrogel, and the main reason for this result was thought to be due to the closure of the active functional groups of the increased cross-links between AMPS and APTMACl monomer. When sorption results were examined, it was observed that the highest heavy metal ion removal for AM1, AP1, and AMAP1 was in As(V) metal. The highest metal ion holding capacity of AM1, AP1, and AMAP1 was found to be 494 mg/g, 2336 mg/g, and 1439 mg/g for As(V), 323 mg/g, 111 mg/g, and 276 mg/g for Cr(III), and 303 mg/g, 723 mg/g, and 554 mg/g for Cr(VI), respectively. Considering the swelling and sorption results, it is thought that the synthesized hydrogels will provide a significant advantage in the removal of heavy metal ions, which have negative effects on environmental pollution and live health. Keyword: copolymeric hydrogel; heavy metal; homopolymeric; sorption kinetics; sorption mechanis More less

Синтез наночастиц меди в присутствии додецилсульфата натрия

Emil ÖMÜRZAK

Article | 2016 | Наука, техника и образование21 ( 3 )

Методом рентгенофазового анализа показано, что фазовый состав продуктов химического восстановления меди гидразином зависит от условий синтеза и присутствия додецилсульфата натрия. Однофазный продукт, состоящий только из наночастиц меди, синтезируется в аммиачной среде в присутствии додецилсульфата натрия.- Ключевые слова: синтез, наночастицы, медь, химическое восстановление, гидразин, додецилсульфат натрия . . . More less

Activated Carbon for Wastewater Treatment from Phenol Compounds

Külümkan SARTOVA | Emil ÖMÜRZAK

Article | 2022 | Chemistry for Sustainable Development30 ( 3 )

Application of activated carbon (AC) obtained from cotton wastes (bolls, stems, and roots) for phenol adsorp-tion from water, or wastewater dephenolization, is presented. The kinetics of phenol adsorption by carbon adsor-bents were studied using UV/Vis spectrophotometer. The porosity of the formed ACs ranged from 1.952 to 2.339 cm3/g, the volume of macropores was from 1.79 to 2.09 cm3/g, while the commercial sample BAU-A showed 1.920 and 1.320 cm3/g, respectively. The highest phenol adsorption rate, 32.49-52.80 mg/(g center dot min), was observed for contact time up to 5 min on carbon adsorbents obtained from cotton waste. The adsor . . .ption equilibrium was achieved within 5 min after the contact, which is shorter than the analogous commercial adsorbents (7-12 min). Sufficiently high phenol adsorption activity of AC from cotton stems, roots and bolls is revealed. Therefore, the use of AC from cotton wastes as adsorbents for the treatment of industrial wastewater to remove organic and other impurities can be recommended for environmental remediation applications More less

A novel carbohydrate antigen 125 electrochemical sensor based on sweet almond oil organo-hydrogels

Nahit AKTAŞ

Article | 2023 | Materials Chemistry and Physics298

Ovarian cancer is a gynecological disease causing many deaths among women around the world. Carbohydrate antigen 125 (CA-125) is a single biomarker known to be a tumor marker of ovarian cancer. CA-125 is widely used to monitor the treatment process, recurrences, and for the detection of ovarian cancer. Herein, organo-hydrogels were prepared in order to detect CA-125 sensitively in serum medium with electrochemical methods. Organo-hydrogels were obtained by the free radical polymerization reaction using agar and glycerol with varying proportions of sweet almond oil using methylene bisacrylamide (MBA) or glutaraldehyde (GA) crosslinke . . .rs. Electrochemical measurements were performed with cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) on organo-hydrogel sweet almond oil (OHSAO) prepared in the presence and absence of CA-125. As a result of these measurements, two distinct linear ranges of 1–50 ng/mL and 100–1000 ng/mL were obtained. In addition, LOD and LOQ values for the sensor were calculated as 0.41 μU/mL and 1.24 μU/mL, respectively. In conclusion, the OHSAO-based electrochemical sensor is a promising electrode for CA-125 detection.Keywords: Organo-hydrogel, Sweet almond, CA-125, Ovarian cancer, Senso More less

Synthesis of poly(Oak bark) particles from oak bark extract and its utilization as a drug carrier material

Nahit AKTAŞ

Article | 2023 | Vietnam Journal of Chemistry61 ( 6 )

As oak bark extract includes pharmaceutically meaningful precious biochemicals such as vanillic acid, quercetin, catechin, caffeic acid, gallic acid, ferulic acid, syringic acid, chlorogenic acid, q-coumaric and protocatechuic acid, the present study focuses on synthesizing polymeric particles from that extract while keeping their targeted natural bioactivity. In this study, due to the bioavailability of oak bark extracts, poly(Oak bark)water extract (p(OB)w), poly(Oak bark)ethanol extract (p(OB)e) and poly(Oak bark)water-ethanol extract (p(OB)we) particles were synthesized using redox polymerization method. Additionally, the biocom . . .patibility, hydrogen peroxide scavenging (H2O2), antioxidant and antimicrobial activities of these substances were investigated. The characterization of the synthesized particles was conducted by FTIR and SEM methods. It was determined that even low amounts of particles (1 mg) had high antioxidant and H2O2 activity. It was found that the particles (0.1 mg/mL) showed antimicrobial activity against Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans within the parameters tested for antimicrobial activity. Paracetamol, which is widely used as a model drug and especially recommended for use in the Covid-19 outbreak, was chosen to test the release potential of the p(OB)w, p(OB)e and p(OB)w-e particles. Paracetamol release studies were measured with a UV-VIS spectrophotometer at pH 7.4 and 37°C. Keyword: antioxidant; biocompatible; H2O2 scavenging; Oak bark extract; particl More less

Electrochemically modified sulfisoxazole nanofilm on glassy carbon for determination of cadmium(II) in water samples

Ali Osman SOLAK

Article | 2013 | Electrochimica Acta105

Sulfisoxazole (SO) was grafted to glassy carbon electrode (GCE) via the electrochemical oxidation of SO in acetonitrile solution containing 0.1 M tetrabutylammoniumtetra-fluoroborate (TBATFB). The prepared electrode was characterized by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), reflection–absorption infrared spectroscopy (RAIRS) and X-ray photoelectron spectroscopy (XPS). The ellipsometric thickness of SO nanofilm at the glassy carbon surface was obtained as 14.48 ± 0.11 nm. The stability of the SO modified GCE was studied. The SO modified GCE was also utilized for the determination of Cd(II) ions . . .in water samples in the presence of Pb(II) and Fe(II) by adsorptive stripping voltammetry. The linearity range and the detection limit of Cd(II) ions were 1.0 × 10−10 to 5.0 × 10−8 M and 3.3 × 10−11 M (S/N = 3), respectively. - Keywords: Sulfisoxazole; Modification; Surface characterization; Nanofilm; Cd(II) ion detectio More less

The investigation of the chemical and technological properties of biomass waste from plant raw materials = Исследование химико-технологических свойств отходов биомассы растительного сырья

Külümkan SARTOVA

Article | 2018 | Химия растительного сырья / Khimiya Rastitel'nogo Syr'ya ( 4 )

Целью данной работы является изучение технического, химического и группового состава биомассы хлопчатника (лат. Gossypium) и полыни – эстрагона (лат. Artemisia Dracunculus L.) для установления их пригодности при получении химических продуктов. Результаты исследования позволили установить, что биомасса хлопчатника и полыни – эстрагона может быть использована в качестве сырья для получения химических продуктов и адсорбентов. Исследование химического состава анализируемых растений показало, что их можно использовать в дальнейшем для получения целлюлозы (37 до 48%), лигнина (21–31%), гемицеллюлоз (11–21%) и пектиновых веществ (6.64 до . . .11.0%). Растительное масло, выделенное из семян полыни – эстрагона, выход которого составляет (15.7%), было обьектом для дальнейшей переработки, в результате которой получены метиловые и этиловые эфиры высших карбоновых кислот, которые могут найти применение в качестве добавок к дизельным топливам. В процессе переработки получены экстрактивные вещества – дубильные, природные красители, липиды (воски), антиоксиданты-полифенолы More less

Dichromate and arsenate anion removal by PEI microgel, cryogel, and bulkgel

Nahit AKTAŞ

Article | 2021 | Journal of Environmental Chemical Engineering9 ( 2 )

Among the various metal ions, chromate (Cr(VI)) and arsenate (As(V)) are the two most hazardous toxic ion species and are found in nature in the form of dichromate and arsenate anions. In this investigation, polyethyleneimine (PEI)-based hydrogels were prepared with microgel, cryogel, and bulkgel morphologies employing glycerol diglycidyl ether as a crosslinker. The prepared PEI-based hydrogels were used to remove dichromate and arsenate anions from aqueous media. PEI microgel, cryogel, and bulkgels weighing 50 mg of each adsorbed 84.7 /- 0.8, 76.5 /- 5.2, and 108.9 /- 2.4 mg.g(-1) of dichromate anions and 15.9 /- 0.7, 45.4 /- 1.9, . . .and 79.2 /- 11.6 mg.g(-1) of arsenate anions in 30, 120, and 240 min, respectively. The dichromate and arsenate anions adsorption of PEI-based hydrogels were found to fit to the pseudo-second-order kinetic, and nonlinear Langmuir isotherm models, respectively with higher R-2 values. The highest distribution coefficient (K-d) value of PEI-based hydrogels for dichromate adsorption was obtained on the cryogel forms of PEI as 1.89 /- 0.05. Likewise, the highest K-d value for the arsenate adsorption was calculated on PEI-based bulkgels as 0.46 /- 0.01. The thermodynamic parameters of PEI based hydrogels in the adsorption of dichromate and arsenate anions e.g., Delta G (all negative (except for the arsenate adsorption by PEI microgels), and Delta H that is around 2-10 kJ.mol(-1), and Delta S what is around 0.01-0.02 kJ.mol(-1). K-1 were calculated. The reusability studies showed that PEI-based hydrogels can be used for at least 5 consecutive adsorption-desorption cycles with almost 70 ?nion removal efficiency after the fifth cycle More less

Determination of Acetaminophen in Commercial Formulations Using Silver Nanostructured Aniline Modified Pencil Graphite Electrode

Ali Osman SOLAK

Article | 2013 | Journal of The Electrochemical Society160 ( 8 )

A nanostructured silver-aniline modified pencil electrode obtained by applying experimental design and optimization was developed for the differential pulse stripping voltammetric quantification of acetaminophen in the pharmaceutical products, tablet and syrup. The electrode development process was performed by the modification of PGE with aniline using CV procedure and the reduction of silver nanoparticle on the polyaniline modified PGE. As a result, a new electrode system consisting of a nanostructured silver-polyaniline modified pencil graphite electrode (AgNS-PA-PGE) was obtained to reach a well-defined and higher peak current f . . .or the analysis of the related drug. The calibration curve was found linear in the range of 5 × 10−8–8 × 10−7 M for acetaminophen. The validity and applicability of the proposed voltammetric method was tested by analyzing independent validation samples. It was observed that the proposed voltammetric approach for the real tablet and syrup samples gave successful analysis results More less

Covalently Grafted on to the Glassy Carbon Electrode in Non-Aqueous Media of Apigenin and Naringenin as Different Flavonoid Derivatives

Ali Osman SOLAK

Article | 2011 | Analytical and Bioanalytical Electrochemistry3 ( 2 )

In this paper, apigenin (AG) and naringenin (NG) have been studied with the cyclic voltammetric technique using the glassy carbon (GC) electrode. The modification was carried out only in non-aqueous media, while the electrochemical characterization was done in both aqueous and non-aqueous media. 0.1 M tetrabutylammonium tetrafluoroborate (TBATFB) in acetonitrile (MeCN) was used in non-aqueous experiments, Britton-Robinson (BR) buffer solution (pH=2) and 0.1 M KCl solution were used in aqueous experiments. Surface modification experiments were performed in the +0.3 V and +2.8 V potential ranges with a scan rate of 0.1 Vs-1 and 10 cyc . . .les for two molecules. The presence of AG and NG at the GC electrode surface was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), contact angle measurement (CAM) technique and atomic force microscopy (AFM). We also investigated the electrochemical oxidation of AG and NG in non-aqueous media and propose a grafting mechanism of AG and NG to the GC electrode surface. - Keywords: Flavonoid, Electrochemical Oxidation, Surface Modification, Surface Characterizatio More less

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