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Based on the generalization of research results on the processes of obtaining SiO2 sols using tetraethoxysilane and ethyl silicates, the main factors influencing the elasticity of silica coatings on cotton fabrics and their fire-retardant properties are considered. The possibility of forming covalent bonds between the functional groups of cellulose, gel coating and flame retardant layer is considered, which explains the strong fixation of a thin layer of coating on the fibers of the fabric and improve its fire protection. The use of the developed compositions for fire-retardant elastic coatings based on ethyl silicate allows to increase the time of complete burning of cotton from 30s (untreated fabric) to 600s (treated with binary coating).

The influence of the degree of homogeneity of the SiO2 sol on the duration of the induction period and the quality of fire-resistant coatings on textile materials was studied. The prospects of using IR spectroscopy as an express method for studying the phase composition of a gel coating, the degree of completion of the hydrolysis of an organosilicon component, and adjusting the parameters for obtaining a high-quality fire-resistant binary coating of a sol SiO2 - flame retardant system are shown.

Carbon dioxide assisted particle formation combined with electrospraying using supercritical CO2 (scCO2) as an aid (Carbon Dioxide Assisted Nebulization-Electrodeposition, CAN-ED) was used to produce Bortezomib loaded poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) P(3HB-co-3HHx) nanoparticles for sustained release. The morphology and structure of the prepared nanoparticles were investigated by SEM, TEM and FT-IR spectroscopy. Average diameter of particles obtained was 155nm and the average core sizes of P(3HB-co-3HHx) nanoparticles were between 6 and 13nm. The drug loading capacity, drug release and stability of Bortezomib loaded P(3HB-co-3HHx) nanoparticles were analyzed. The maximum loading capacity was achieved at pH=6.0 in phosphate buffer (K2HPO4/KH2PO4). It was found that temperature did not affect the stability of Bortezomib loaded nanoparticles and it was good both at 37°C and 4°C. This study pointed out that CAN-ED is a green method to produce P(3HB-co-3HHx) nanoparticles for pH responsive targeting of Bortezomib especially to parts of the body where size exclusion is not crucial.

In this work, reduced graphene oxide (rGO) based electrode materials were developed to achieve a hybrid supercapacitor (SC) function. Therefore, several synthesis methods were developed to prepare a cost effective and environmentally friendly rGO. Additionally, to maintain the high surface area, spinel lithium titanate (sLTO) nanoparticles (NPs) were synthesized and deposited on the rGO surface to inhibit the restacking of the rGO layers on graphite. Furthermore, the adequate Fe-doping of sLTO increased the ionic conductivity and the intercalation capacity, which is necessary for a SC performance. The sLTO/rGO-composites were electrochemically analysed by chronopotentiometry and electrochemical impedance spectroscopy (EIS) to determine the stability during charge/discharge cycling and the capacity, respectively. To overcome the drawback of LTO's low conductivity values, its value has been drastically increased by Fe-doping. The results demonstrated the remarkable cycling performance of the Fe:LTO/rGO composite as well as a higher capacity compared to LTO/rGO and pure rGO-electrodes. The thermal stability, degradation and weight loss of the sLTO/rGO in the temperature range between 20 °C and 800 °C were investigated by thermogravimetry (TG)/DTA. As a conclusion, it can be stated that, increasing the ionic conductivity by Fe-doping drastically increases the hybrid capacity of the SC electrodes.

The complexes represented with the general formula [ML2Cl2] (L: 2-fluoropyridine; M: Ni (II), Cu (II), Co (II)) were synthesized and their structures were characterized via FT-IR and H-1 NMR techniques. Thermal properties of the complexes were also investigated via TG/DTA combined system under N-2 atmosphere. The complexes containing cellulose acetate (CA) micro/nano-fibers, which is a biocompatible and biodegradable polymer, were obtained via electrospinning technique. The fibers were characterized via FT-IR spectroscopy. FE-SEM images of the fibers were used to investigate their morphologies and for to determine the diameters of the fibers. Thermal properties of the fibers were investigated via TG/DTA combined system. Antibacterial studies of the complexes and fibers were investigated against the bacteria strains E. coli and Methyciline Resistant Staphylocaucus aureus via disc diffusion, broth microdilution and JIS L 1902: 2008, Testing method for antibacterial activity of textiles. Different levels Antibacterial activity was observed for all complexes and fibers. (C) 2019 Elsevier B.V. All rights reserved.

Novel pyridine derivative platinum complexes with the general formula [PtCl2L2] (L1: 2-fluoropyridine, L2:2-amino-3-methyl pyridine) were synthesized and their structural characterizations were made using FT-IR, UV–vis, 1H NMR, and 13C NMR techniques as well as via the theoretical calculations. Using the DFT/MPW1PW91 method with LanL2DZ basis set the most probable molecular structure for the most stable complexes was determined. The potential energy distribution analysis was made for to confer the complexes their vibrational assignments. The molecular electrostatic potential, highest occupied molecular orbital and lowest occupied molecular orbital were also calculated. The thermal decomposition reactions of the complexes were investigated via DTA/TG combined system. The decomposition kinetics were calculated by using FWO and KAS methods. The average activation energies of the complexes were calculated to be 31.72–184.61 kJ/mol via FWO and 29.17–184.53 kJ/mol via KAS methods. The cytotoxicity of the complexes was tested against colon cancer cell line (DLD-1) and the [PtCl2L12] complex was found to be more effective than [PtCl2L22] against over 24 h incubation period. The results showed that thus synthesized pyridine-derived platinum complexes may be used as effective chemotherapeutic agents in treatment of colon cancer.

Cu2ZnSnS4 (CZTS) nanoparticles (NPs) were prepared by a simple hydrothermal method, and their cytotoxic, antiproliferative and proapoptotic activities on human non-small cell lung adenocarcinoma A549 cells were investigated for the first time, and the morphological and ultrastructural changes of these cells were monitored. The structural characterizations of the synthesized nanoparticles were made by using Field Emission-Scanning Electron Microscope (FE-SEM), X-Ray Powder Diffraction (XRD) and Raman techniques. Cytotoxicity and confocal microscopy studies revealed that the CZTS NPs effectively entered into the A549 cells in a dose-dependent not time-dependent manner over a period of 24 and 48 h. It was observed that the CZTS NPs had a negligible cytotoxic effect and considerable antiproliferative and proapoptotic activities. The low cytotoxicity of the CSTZ NPs and their potent anticancer activity against A549 cells highlight their potential to be used as anticancer agents. This study may pave the way for designing and constructing various morphologically diverse, nanotextured materials with desired functional attributes.

Indium sulfide thin films consisting of In2S3 and In6S7 phases were synthesized onto microscope glass substrates with different nanoparticle size using the chemical bath deposition method (CBD). Immediately after obtaining the films, they were annealed at 400 degrees C for 1 h in reduced media in order to get better crystallization. The effect of nanoparticle sizes on the structural, compositional, optical, and electrical properties of the films was investigated. The films were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive x-ray spectrometry (EDS), UV-Vis spectroscopy and sheet resistivity measurements. The XRD spectra revealed the existence of both the cubic In2S3 and monoclinic In6S7 phases. From the SEM micrographs, the deposited films showed dense and good coverage of the surface with cracks. Moreover, nanoparticle sizes increased from 53 nm to 142 nm with increasing deposition time as well as film thickness. With an increase in nanoparticle size, the S/In ratio in the films decreased from 1.74 to 1.21 showing sulfur deficiency in the deposited films. The direct band gap (E-g) of the films decreased from 3.35 eV to 2.70 eV with increasing nanoparticle size. The sheet resistivity of the films decreased from 1.69 x 10(7)Omega/Sq to 4.61 x 10(3)Omega/Sq. The obtained results demonstrate that nanoparticle sizes effected the structural, compositional, optical and sheet resistivity of the films. (C) 2020 Elsevier B.V. All rights reserved.

Sr4-xAl14O25:xEu(3+) (x varies from 0.02 to 0.06) phosphors were prepared at high temperature via solid-state method. The crystal structure of Sr4Al14O25:Eu3+ was determined to be orthorhombic crystal system with Pmmm space group. The excitation spectrum of Sr3.96Al14O25:0.04Eu(3+) shows four excitation bands at 308 nm, 360 nm, 383 nm, and 411 nm, respectively. The first excitation band, which is centered at 308 nm, is assigned to the charge-transfer (CTLM) band of Eu3+-O-2, and others are assigned to intra-4f transitions between 393 nm and 450 nm. The emission spectrum of Sr3.96Al14O25:0.04Eu(3+) exhibits a series of emission bands which are attributed to the D-5(0)-F-7(j) (j = 0-4) transitions of Eu3+ ions. The luminescence studies revealed that the Eu3+ ions show high luminescence efficiency in emitting red light at 616 nm. The thermo-luminescence glow curve of Sr3.96Al14O25:0.04Eu(3+) shows three overlapped glow peaks between 100 degrees C and 400 degrees C which are related to the defects at different trap depths. One of the selected glow curves was analyzed by using glow curve deconvolution (GCD) method. In order to explore the related kinetic parameters of P1 Gartia, Singh & Mazumdar peak shape (PS) method was also used. (C) 2016 Elsevier B.V. All rights reserved.

The target of this study is to determine the interrelation among serum Li level on bone metabolism (Ca, P, Parathormon, and Vitamin-D), sex and metabolic hormones (estrogen, FSH, LH and TSH), and some biochemical parameters in premenopausal and postmenopausal women. The study is carried out with 10 women: 5 premenopausal and 5 postmenopausal women. The serum Li levels, bone metabolism indicators (i.e., ALP, Ca, P, Mg, Cu, Zn) and some biochemical parameters such as serum tryglyceride, alkalene phosphatase, total cholesterol, HDL, LDL and cholesterol levels were determined. The estrogen blood level of women in menopause period was found to be lower than that of women in pre-menopause period (p

The stability of the optical parameters of a ruthenium polypyridyl complex (Ru-PC K314) film under varying annealing temperatures between 278 K and 673 K was investigated. The ruthenium polypyridyl complex thin film was prepared on a quartz substrate by drop casting technique. The transmission of the film was recorded by using Ultraviolet/Visible/Near Infrared spectrophotometer and the optical band gap energy of the as-deposited film was determined around 2.20 eV. The optical parameters such as refractive index, extinction coefficient, and dielectric constant of the film were determined and the annealing effect on these parameters was investigated. The results show that Ru PC K314 film is quite stable up to 595 K, and the rate of the optical band gap energy change was found to be 5.23 × 10- 5 eV/K. Furthermore, the thermal analysis studies were carried out in the range 298-673 K. The Differential Thermal Analysis/Thermal Gravimmetry/Differantial Thermal Gravimmetry curves show that the decomposition is incomplete in the temperature range 298-673 K. Ru-PC K314 is thermally stable up to 387 K. The decomposition starts at 387 K with elimination of functional groups such as CO2, CO molecules and SO3H group was eliminated between 614 K and 666 K., State Planning Organization of Turkey (DPT2003K120390); Scientific and Technological Research Council of Turkey (TBAG-109T240)

Ca1-xMoO4:xEu3+ (x varies from 0.02 to 0.07) phosphors were prepared via complex polymerization method (CPM). It was determined that CaMoO4:Eu3+ has powellite crystal structure with space group ??41/?? (No.88). The cell parameters are ?? = ?? = 5.217 A and ?? = 11.414 A. The intense bands observed in the excitation spectrum of Ca0.95MoO4:0.05Eu3+ at 240 nm and 281 nm belong to the charge transfer transition in O2− → Mo6+ and O2− → Eu3+ groups and these bands overlap with each other. Aside from these bands, five other bands were observed in the excitation spectrum between 350 and 500 nm that belong to 7F0→5D4, 7F0→5G4, 7F0→5L6, 7F0→5D2, 7F0→5D2 electronic transitions of Eu3+. The emission spectrum of Ca0.95MoO4:0.05Eu3+ exhibits a series of emission bands between 550 nm and 750 nm that can be attributed to the 5D0→7Fj (j = 0–4) transitions of Eu3+ ions. The thermoluminescence properties of Ca0.95MoO4:0.05Eu3+ were investigated in detail and the glow curves were analyzed via glow curve deconvolution (GCD) method. The results showed that Ca0.95MoO4:0.05Eu3+ was composed of four general order TL glow peaks. The f(D) function was investigated at a heating rate of 1 °C/s and the linear (f(D) = 1) behavior of the curves at very low doses was found to be followed by a supralinear (f(D) > 1) behavior up to nearly 102 Gy.

Mesoporous 2-Chlorobenzoylthiourea-modified MCM-41 was prepared and loaded with ibuprofen in a supercritical carbon dioxide (sC-CO2) environment. 2-chloro-benzoythiourea modified MCM-41 was prepared and also characterized via XRD, FT-IR, SEM and BET techniques. The (100) and (110) reflections observed at low angle XRD show the mesoporous SiO2 structure. The paticule size of non-uniform spheres were observed at a range of 250-305 nm. BET surface areas were calculated as 1506 m2 / g for MCM-41 and 306 m2/g 2-chloro-benzoythiourea modified MCM-4, respectively. The absorption and releasing studies of ibuprofen were caried out in simulated body fluid. The result revealed that high adsorption capacity for drug with 2-chloro-benzoythiourea modified MCM-41 and slower drug release rate was achieved.

ZnO nanopowder was synthesized via a hydrothermal route and characterized with several methods such as XRD, TG/DTA, FT-IR, FE-SEM, TEM and Electron Paramagnetic Resonance spectroscopy (EPR) in order to investigate the effect of growing time and Mn doping on the defects which occurred. The pure ZnO nanopowder was obtained in a hexagonal phase with (101) as the preferred orientation except for the one prepared for 36 h which is (002). The growing time does effect the orientation of the crystallite whereas the Mn-doping does not. The concentration of Mn2+ significantly increases the spin–spin interaction in the ZnO : Mn nanopowder. It was observed that there was a competition between intrinsic (Zn and O vacancies) and extrinsic (Mn2+ ion) structural defects but still the former defects are dominant in ZnO : Mn. The effect of growing time and concentration of Mn2+ on the activation energy of ZnO and the ZnO : Mn nanopowder are calculated by Kissinger–Akahira–Sunose (KAS) and Flynn–Wall–Ozawa (FWO) methods.

The [Cu(pydc)(eim)3]·H2O (1), [Cu(pydc)(4hp)(H2O)] (2) and [Ni(pydc)(3hp)(H2O)2][Cu(pydc)(3hp)(H2O)2]·3H2O (3) complexes (H2pydc = 2,6-pyridinedicarboxylic acid or dipicolinic acid, eim = 2-ethylimidazole, 4hp = 4-hydroxypyridine, 3hp = 3-hydroxypyridine) were studied by thermo-gravimetric analysis at an ambient temperature up to 1000 K under nitrogen atmosphere. The complexes are stable about 350 K, and the decomposition reactions were carried out in seven, three and four stages for the complexes 1, 2 and 3, respectively. Following detailed thermo-gravimetrical analysis of the complexes, the decomposition mechanism was suggested for all complexes. The kinetic analysis of all decomposition stages of each compound was performed except for the final stages. The values of the activation energy, Ea, were obtained using model-free Kissinger–Akahira–Sunose and Flyn–Wall–Ozawa methods for all decomposition stages. © 2016, Akadémiai Kiadó, Budapest, Hungary.