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901.
Baran Y Ozay H Esener H Turkyilmaz M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):99-103
A new crystal of N-(acetamide) morpholinium (NAM) bromide has been prepared in methanol at room temperature and characterized by single crystal X-ray analysis, elemental analysis, GS-MS, FTIR, NMR((1)H,(13)C, DEPTH and HETCOR). The N-(acetamide) morpholinium crystallizes in the orthorhombic crystal system, Pnma with unit cell a=12.798(9) ?, b=7.222(5) ?, c=9.244(5) ?, β=90.00, V=854.4(9) ?(3), Z=4. The X-ray structure determination revealed that there are strong inner and intermolecular hydrogen bonds in the crystal. 相似文献
902.
Li Zhao Zhiwei Hu Chang‐Yang Kuo Tun‐Wen Pi Maw‐Kuen Wu Liu Hao Tjeng Alexander C. Komarek 《固体物理学:研究快报》2015,9(12):730-734
From magnetic susceptibility, dielectric permittivity, electric polarization and specific heat measurements we discover spin‐induced ferroelectricity and magnetoelectric coupling in Mn3TeO6 and observe two successive magnetic transitions at low temperatures. A non‐ferroelectric intermediate magnetic state occurs below 23 K and a multiferroic ground state emerges below 21 K. Moreover, Mn3TeO6 is a candidate for a multiferroic material where two types of incommensurate spin structures, cycloidal and helical, coexist. Theoretically, both spin substructures may contribute to the macro electric polarization via different mechanisms. This could open new ways of manipulating the ferroelectric polarization in a multiferroic material. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
903.
Murat Faruk Us Usama Alshana Ibrahim Lubbad Nilgün G. Göğer Nusret Ertaş 《Electrophoresis》2013,34(6):854-861
Dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME–SFO) was for the first time combined with field‐amplified sample injection (FASI) in CE to determine four β2‐agonists (cimbuterol, clenbuterol, mabuterol, and mapenterol) in bovine urine. Optimum BGE consisted of 20 mM borate buffer and 0.1 mM SDS. Using salting‐out extraction, β2‐agonists were extracted into ACN that was then used as the disperser solvent in DLLME–SFO. Optimum DLLME–SFO conditions were: 1.0 mL ACN, 50 μL 1‐undecanol (extraction solvent), total extraction time 1.5 min, no salt addition. Back extraction into an aqueous solution (pH 2.0) facilitated direct injection of β2‐agonists into CE. Compared to conventional CZE, DLLME–SFO–FASI–CE achieved sensitivity enhancement factors of 41–1046 resulting in LODs in the range of 1.80–37.0 μg L?1. Linear dynamic ranges of 0.15–10.0 mg L?1 for cimbuterol and 15–1000 μg L?1 for the other analytes were obtained with coefficients of determination (R2) ≥ 0.9901 and RSD% ≤5.5 (n = 5). Finally, the applicability of the proposed method was successfully confirmed by determination of the four β2‐agonists in spiked bovine urine samples and accuracy higher than 96.0% was obtained. 相似文献
904.
Hüseyin Karaca Devrim Türker Murat Teker 《Journal of Dispersion Science and Technology》2013,34(12):1800-1807
AbstractIn this study the effect of the dose and particle size of the adsorbent, initial dye concentration, initial pH, contact time and temperature were investigated for the removal of by means of fly ash (FA) methylene blue (MB) from an aqueous solution. The FA dose was found to be 2.0?g and the under 270 mesh sized particles were found to be effective particles for adsorption. The adsorption process reached its maximum value at 0.5?mg/L dye concentration and attained equilibrium within 10?minutes. The adsorption isotherm was found to follow the Langmuir model. The estimated adsorption free energy (ΔGo), enthalpy change (ΔHo), and entropy change (ΔSo) for the adsorption process were ?37.77?kJ mol?1, ?13.44?kJ mol?1 and 122 J mol?1 K?1 respectively at 298 K. The maximum adsorption capacity is 0,12?mg g?1 at 298 K and 0,07?mg g?1 at 398 K. The adsorption process was exothermic, feasible and spontaneous. The positive value of ΔSo shows the affinity of FA for MB while the low value of ΔGo suggests a physical adsorption process. 相似文献
905.
Orhan Acar Murat Ilim Ziya Kiliç A. Rehber Türker 《International journal of environmental analytical chemistry》2013,93(12):869-878
Cadmium, lead, copper and manganese were determined in human deciduous teeth and bone ash 1400 standard reference material by electrothermal atomic absorption spectrometry (ETAAS), using a lanthanum + palladium + citric acid (CA) modifier mixture. Optimum masses and mass ratios of La, La + Pd and La + Pd + CA modifiers for analytes in bone ash 1400 sample solution were investigated. Pyrolysis and atomization temperatures of analytes in a tooth sample solution were obtained with and without modifiers. The mixture of La + Pd + CA was found to be preferable for the determination of analytes in tooth samples and bone ash 1400, dissolved in a mixture of HNO3 + H2O2. The detection limits and characteristic masses of analytes were obtained with or without modifiers based on integrated absorbance for tooth sample solution (2% m/v). The detection limits obtained with La + Pd + CA are 6,24,16 and 46 ng g?1 for Cd, Cu, Mn and Pb, respectively. Recovery tests for analytes in bone ash 1400 and a tooth solution with La and La + Pd + CA modifier mixture were studied and compared with certified and non certified values. The La + Pd + CA mixture was also applied to the determination of Cd, Pb, Cu and Mn in tooth samples. 相似文献
906.
Murat Genc Engin Yılmaz Selcuk Ilhan Zuhal Karagoz 《Research on Chemical Intermediates》2013,39(7):3011-3021
In this study, (4-methoxybenzyl)(1,4,5,6-tetrahydropyrimidin-2-yl)amine hydroiodide (2) was synthesized by reaction of 2-methylmercapto-1,4,5,6-tetrahydropyrimidine hydroiodide (1) and 4-methoxybenzylamine. The synthesized compound was tested for its in vitro H1-antihistaminic activity on guinea pig trachea. A promising bronchorelaxant effect of 2 was observed in histamine-contracted guinea pig tracheal chain via H1 receptor antagonism. In addition, the molecular geometry and gauge including atomic orbital (GIAO) 1H chemical shift values of the title compound in the ground state were calculated using the density functional method (DFT/UB3LYP) and Hartree–Fock (HF) approach using 6–311G+(d), 6–311G+(d,p), LANL2DZ, DGDZVP, and DGDZVP2 basis sets and compared with the experimental data. According to the experimental and theoretical results, HF/6–311G+(d) showed a better fit to experimental values in evaluating 1H-nuclear magnetic resonance (NMR) chemical shift values. Theoretical studies supported our findings, revealing the N12 atom as the most nucleophilic. In addition, other structures of the compound such as the aromatic ring and OCH3 group increased this property. 相似文献
907.
Serkan Elçin Murat Muzaffer İlhan Hasalettin Deligöz 《Journal of inclusion phenomena and macrocyclic chemistry》2013,77(1-4):259-267
In this study, the synthesis and characterization of two new upper rim functionalized azocalix[4]arene dyes have been obtained by coupling calix[4]arene with different diazo compounds of 3,5-dicarboxyaniline and 4-aminobenzene sulphon amide. The characterization of these dyes has been carried out by elemental analysis, FT-IR and 1H NMR spectra. The effect of varying dielectric constants of solvents on the absorption spectra of azocalix[4]arenes (1, 2, 3, 4) and commercial Isolan Gelb SGL (T) have been examined by UV–Vis spectrophotometer. These azocalix[4]arene dyes have also been used for dyeing textile fibers like cotton, wool, acetate, polyester and polyamide fibers. Their dyeing and fastness properties have also been discussed. 相似文献
908.
Murat Erdemoğlu 《Journal of Dispersion Science and Technology》2013,34(5):689-695
Electrokinetic behavior of pyrophyllite in aqueous solutions of K+, Na+, Mg2+, and Ca2+ ions and effect of low‐molecular‐weight organic anions like acetate (C2H3O2 ?), oxalate (C2O4 2?), and citrate (C6H5O7 3?) on the zeta potential was investigated. Pyrophyllite has higher negative zeta potential values in the presence of alkaline metal cations than in water, and it comes close to positive values in the presence of alkaline earth metal cations at low pH values. Results revealed that presence of low‐molecular‐weight organic anions led to a decrease in the zeta potential in the order of acetate>citrate>oxalate. 相似文献
909.
In this study, the mechanical properties and non‐isothermal degradation kinetics of polypropylene (PP), high‐density polyethylene (HDPE) with dilauroyl peroxide and their blends in different mixture ratios were investigated. The effects of adding dilauroyl peroxide (0–0.20 wt%) on the mechanical and thermal properties of PP + HDPE blends have been studied. On the other hand, the kinetics of the thermal degradation and thermal oxidative degradation of PP + HDPE (80/20 wt%) blends were studied in different atmospheres, to analyze their thermal stability. The kinetic and thermodynamic parameters such as the activation energy, Ea, the pre‐exponential factor, A, the reaction order, n, the entropy change, the enthalpy change, and the free energies of activated complex related to PP, HDPE, and blend systems were calculated by means of the several methods on the basis of the single heating rate. A computer program was developed for automatically processing the data to estimate the reaction parameters by using different models. Most appropriate method was determined for each decomposition step according to the least‐squares linear regression. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
910.
生物传感器是近年来的热点研究方向,其中基于折射率变化的光学传感器在灵敏度方面具有很大优势.本文基于α-MoO3设计了一种集成微流腔的法布里-珀罗谐振腔比色生物传感器.理论分析了BK7/Ag/SiO2作为谐振腔反射面的可行性,并进一步用传输矩阵法分析了所设计的比色生物传感器的透射光谱.当微流腔通过不同浓度的NaCl溶液时,比色生物传感器显示出明显的颜色变化.该比色生物传感器灵敏度最高可达600 nm/RIU,可分辨NaCl溶液9‰的浓度变化.由于α-MoO3具有独特的各向异性的光学性质,该比色传感器可以通过简单的旋转设备实现工作波长的调节以更好地适应人眼的光敏感区.另一方面,调节微流腔的厚度也改变该比色生物传感器的工作波长.该比色生物传感器具有结构简单、易于集成、操作成本低、实时检测等优点,为以后设计可调谐比色传感器提供了一种新的选择. 相似文献