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22.
Ayça Tunçel Kasim Ocakoglu Suleyman Gokhan Colak Osman Yılmaz İsmail Öztürk Fatma Yurt 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(3):487-492
Effective antimicrobial compounds are necessary due to increased resistance of antibiotics against microorganisms causing infectious diseases. In this study, imidazolium-TFSI salt [ITFSI: octyl-bis(3-methylimidazolium)-di(bis(trifluoromethane)sulfonimide)] was labeled with 131I with high efficiency. In vitro uptake experiments of 131I-ITFSI showed high uptake in gram-positive Staphylococcus aureus bacteria. 131I-ITFSI was also evaluated for comparison between bacterial infection and sterile inflammation by in vivo studies. The biodistribution results revealed that 131I-ITFSI might be used as a nuclear imaging agent for detection of bacterial infection. 相似文献
23.
Namk
zdemir Demet Astley Stephen T. Astley Muharrem Diner Gamze Doaner 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):m147-m149
The title compound, [Zn(C15H11N7O4)(H2O)2](NO3)(PF6)·3H2O, contains a mononuclear zinc(II) complex. The Zn2+ centre is seven‐coordinated in a slightly distorted pentagonal–bipyramidal geometry, with the two water O atoms located in the apical positions, and the pyridine N atom, the two imine N atoms and two carbonyl O atoms of the uracil groups located in the equatorial plane. The charge is balanced by PF6− and NO3− anions. 相似文献
24.
Demet Astley 《Tetrahedron letters》2004,45(39):7315-7317
Substitution of the chloro group in 2-(2-chlorophenyl)-4,4-dimethyl-2-oxazoline to afford biaryls occurs upon reaction with either aryllithium reagents or aryl Grignard reagents. The reactions with Grignard reagents occur under similar conditions to a previously reported manganese-catalysed procedure. The reactions with lithium reagents, whilst not always affording greater yields of product than the Grignard reagents, involve much shorter reaction times and afford yields, which are comparable with those obtained from the corresponding fluoro derivative. 相似文献
25.
In this study, the absorption experiments which are an application area in XRS are discussed. The effect on the absorption parameters of the pressure applied to make pellet powder samples was investigated. The mass attenuation coefficients ( μ m ), mean free paths and half-value layers of samples prepared at different pressures were experimentally determined. C6H10O5, VF4, CaO and Y2O3 samples were pressed at 1.91, 3.82, 5.72 and 7.63 tons/cm2. A variable energy x-ray source from Amersham (AMC.2084) was used in order to irradiate the samples at energies 13.39, 19.63, 24.90, 32.06, 36.39, 44.48, 51.70 and 59.54 keV. The photon intensities were measured by using an HPGe detector with a resolution of 182 eV at 5.9 keV. The theoretical radiation absorption parameters were calculated by WinXCOM program. The calculated values were compared with the experimental values. Good agreement has been observed within experimental uncertainties for low pellet pressure. The obtained results show that the radiation absorption parameters change with the amount of pressure applied to the sample. 相似文献
26.
Glass transition during bulk polymerization was studied in free-radical cross-linking copolymerization (FCC) of methyl methacrylate (MMA) using the steady-state fluorescence (SSF) technique. Naphthalene (N) was used as a monomer and excimer forming probe. Changes in the viscosity of the pregel solutions due to gel formation dramatically enhance both monomer and excimer fluorescent yield of N molecules. The reaction time at which the monomer and excimer intensities exhibit a sudden increase corresponds to the reaction time at which the rate of polymerization becomes maximum resulting from the gel effect. This effect was used to study the gelation of MMA, as a function of time, in various N concentrations. The results were interpreted in the view of percolation theory. The gel fraction, β, and weight average degree of polymerization, γ, exponents β?=?0.40?±?0.02 and γ?=?1.70?±?0.07 were found in agreement with percolation results for both monomer and excimer measurements, respectively. 相似文献
27.
Mehmet Akdeniz Ismail Yener Demet Dincel Mehmet Firat Dilek Karatas Degirmenci Abdulselam Ertas 《Biomedical chromatography : BMC》2022,36(2):e5263
Public use of Salvia species and their importance in the scientific world is continually increasing. It is known that this use and the importance of Salvia species are mostly due to the terpenoid compounds that they contain. In this context, the terpenoid–steroid–flavonoid contents of extracts of six endemic Salvia (S. kurdica, S. pseudeuphratica, S. rosifolia, S. siirtica, S. cerino-pruinosa var. cerino-pruinosa and S. cerino-pruinosa var. elazigensis) species prepared with different solvents were determined by gas chromatography–mass spectrometry. Within the framework of the ingredient analysis, content analysis of the ethanol extracts of the root, branch, leaf and flower parts of the species collected in the same period between 2015 and 2017 years was performed. In general, extracts prepared with chloroform and ethanol were found to contain a wide variety of compounds while petroleum ether extracts were found to contain much less varied compounds. In addition, in general, root extracts are richer in terpenoid compounds than aerial part extracts. Some species can be used as source species in terms of ferruginol, cryptanol, 6,7-dehydroroyleanone, lup-(20)29-ene-2α-hydroxy-3β-acetate, salvigenin and β-sitosterol contents (52,114.28, 75,979.08, 101,247.41, 40,071.29, 33,952.13 and 34,010.90 μg analyte/g extract, respectively). 相似文献
28.
We discuss an improved jackknifed Durbin–Watson estimator for the variance parameter from a steady-state simulation. The estimator is based on a combination of standardized time series area and Cramér–von Mises estimators. Various examples demonstrate its efficiency in terms of bias and variance compared to other estimators. 相似文献
29.
Background
Cytochrome P450 monooxygenases (CYPs) form a vast and diverse enzyme class of particular interest in drug development and a high biotechnological potential. Although very diverse in sequence, they share a common structural fold. For the comprehensive and systematic comparison of protein sequences and structures the Cytochrome P450 Engineering Database (CYPED) was established. It was built up based on an extensible data model that enables its functions readily enhanced. 相似文献30.
A. A. Vertiy S. P. Gavrilov S. Helhel B. Colak R. Samedov 《International Journal of Infrared and Millimeter Waves》1996,17(3):543-557
Results of an experimental study and a calculation of the quasi-optical multilayered structure formed by an adjustable dielectric interferometer and a liquid investigated filling its gabs are presented. It is shown that this structure may be used for quality tests of liquid petroleum products, for measurement and investigation of physical parameters of liquid media in the millimeter wavelengths region. This structure is realized practically in the form of uncomplicated adjustable quazi-optical quvette filled with liquid and connected with beam-guiding elements. Comparison of experimental data with theoretical calculations gives us the opportunity to choose a value region of the values for the physical parameters interesting for us for each material under investigation. 相似文献