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61.
Cationic diimine Ru(II) complexes were synthesized and tested as catalysts for the formation of cyclic organic carbonates from CO2 and liquid epoxides (propylene oxide, epichlorohydrine, 1,2‐epoxybutane and styrene oxide) which served as both reactant and solvent. The reaction rates not only depended on the type of ligand, but also on reaction conditions such as temperature, pressure, base, the epoxide substrates and the use of an additional solvent. Reaction rates in terms of turnover frequencies up to 4050 molproduct molcat.?1 h?1 at 99% selectivity were achieved by optimizing the diimine ligand as well as the reaction temperature and CO2 pressure. Consistent with CV measurements, the electron donating group on the p‐position of the aryl ring accelerated the reaction rate. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
62.
Yusuf Kurtulmus T. Tanyalçın Giray Bozkaya Ogˇuzhan Gündüz Ömür Çerçi Fatma Z. Kutay Biltan Ersöz 《Accreditation and quality assurance》2001,6(9-10):424-426
The aim of this study was to compare two immunoassay measurement methods, the ACS:180 Plus (Chiron Diagnostics) kit and the Immulite sPSA (DPC) kit. Method comparison analysis was performed according to EP9-A; approved guideline of NCCLS 51. Serum samples having a wide range of total prostate-specific antigen (PSA) concentrations were evaluated in split-sample analysis. F-test, t-test analysis and regression statistics were performed. In Deming regression analysis the coefficients were as follows; the slope=0.967; y-intercept=-0.148, r=0.989. An acceptable bias was seen since the systematical error was calculated to have a value less than the total allowable error calculated from biological variations. Non-parametric evaluation of the area under ROC curves for ACS:180 Plus and Immulite sPSA were 0.997 and 0.987, respectively. Diagnostic accuracy was at the level of p= 0.000 and no statistical difference was found between the two assay methods. 相似文献
63.
T. Çuçi J. Thereska N. Dhamo E. Plasari 《Journal of Radioanalytical and Nuclear Chemistry》1989,136(6):449-453
An experiment on rabbits was carried out with the aim to check results obtained formerly with the help of the neutron activation analysis indicating that Na+ ions can be /by contrast to K+ ions/ only very slowly removed from the bone tissue by extraction with water. The data resulting from a radiotracer experiment with22Na are in a good agreement with the above mentioned results. 相似文献
64.
Selçuk Demir Hamide Merve Çepni Małgorzata Hołyńska Muammer Kavanoz Fatih Yilmaz Yunus Zorlu 《Journal of Coordination Chemistry》2017,70(19):3422-3433
Via an oxidation reaction of Cu(I) iodide with pyridine-2,6-dicarboxylic acid (H2L) in DMF three copper(II) complexes, [(CH3)2NH2]2[CuL2] (1), K2[CuL2]?H2L?H2O (2) and [Cu(L)(H2O)]n (3), were synthesized and characterized. The structures of 1–3 were determined by single crystal X-ray diffraction studies. In-situ DMF decomposition produces dimethylamine base under solvothermal conditions and a proton transfer reaction takes place for the complex formation of 1. 3-D networks are stabilized in 1 and 2 via hydrogen bonds. Complex 3 is a 1-D coordination polymer with Cu-O semi-coordination bonds. Thermal decomposition of the complexes results in the corresponding metal oxides. Also, the electrochemical behavior of 1 was determined to be a metal-centered and diffusion-controlled, one-electron reduction process. 相似文献
65.
Esin Burunkaya Nadir Kiraz Ömer Kesmez Meltem Asilturk H. Erdem Çamurlu Ertuğrul Arpaç 《Journal of Sol-Gel Science and Technology》2010,56(2):99-106
In this study, new fluorinated silane system was prepared by adding hydroxyl terminated Fluorolink D10H oligomer to 3-isocyanatopropyltrietoxysilane. The obtained silane system was independently composed with 3-Glycidyloxypropyltrimethoxysilane
and 3-Glycidyloxy-propyltriethoxysilane. Then the prepared two different coating solutions were applied to glass surface by
spin-coating method. The chemical bonding between groups in system was investigated by FTIR analysis. The elemental composition
of coatings was determined by using EDX analysis. Their structure and surface properties were analyzed by scanning electron
microscopy, atomic force microscopy, contact angle measurement and UV–vis spectrophotometer. The amounts of fluorine on the
coatings prepared with IPTES-D10H-GLYEO and IPTES-D10H-GLYMO were 33 and 34 %wt, respectively. Transparent coatings with smooth
surface and uniform thickness were obtained. The coatings had nanoscale roughness. The contact angles of coatings for water
were range from 103° to 110°, and for n-hexadecane were range from 59° to 62°. 相似文献
66.
Savaş Sönmezoğlu Sevilay Şenkul Recep Taş Güven Çankaya Muzaffer Can 《Solid State Sciences》2010,12(5):706-711
We have formed conjugated polymeric aniline–thiophene organic material on p-Si substrate by adding polyaniline–poly-3-methyl thiophene blend solution in acetonitrile on top of a p-Si substrate and then evaporating the solvent. It has been seen that the forward bias current–voltage (I–V) characteristics of polyaniline–poly-3-methyl thiophene blend/p-Si/Al with a barrier height value of 0.60 eV and an ideality factor value of 3.37 showed rectifying behaviour at room temperature. The polyaniline–poly-3-methyl thiophene blend/p-Si/Al Schottky barrier diode showed non-ideal I–V behaviour with the value of ideality factor greater than unity that could be ascribed to the interfacial layer, interface states and series resistance. Furthermore, Cheung's functions and modified Norde's function were used to extract the diode parameters including ideality factor, barrier height and series resistance. It has been seen that there is a good agreement between the barrier height values from all methods. However, the values of series resistance obtained from Cheung's functions is higher than the values obtained from Norde's functions. The energy distribution of interface states density, determined from forward bias current–voltage (I–V) characteristic technique at room temperature, increases exponentially with bias from 2.81 × 1016 cm?2 eV?1 in (0.73–Ev) eV to 1.14 × 1017 cm?2 eV?1 in (0.48–Ev) eV. 相似文献
67.
In the present work, a novel Schiff-base was synthesized by the reaction of saccharin with tryptophan and characterized by elemental analysis as well as UV-Vis, FT-IR, 1H NMR spectroscopic data. The voltammetric behavior of Schiff-base was also studied on the hanging mercury drop electrode (HMDE) by using Square-Wave Voltammetry (SWV) and Cyclic Voltammetry (CV) techniques. The voltammograms of the Schiff-base exhibited two irreversible reduction peaks in Britton-Robinson buffer (pH 7.0–10.0) for the potential range from 0.0 V to ?1.4 V. These peaks which appeared at more positive potentials than the reduction peaks of tryptophan and saccharin, may be assigned to the cathodic reductions of C-N+ and >C=N- moieties of Schiffbase. 相似文献
68.
Çapoğlu İR White CA Rogers JD Subramanian H Taflove A Backman V 《Optics letters》2011,36(9):1596-1598
Rigorous numerical modeling of optical systems has attracted interest in diverse research areas ranging from biophotonics to photolithography. We report the full-vector electromagnetic numerical simulation of a broadband optical imaging system with partially coherent and unpolarized illumination. The scattering of light from the sample is calculated using the finite-difference time-domain (FDTD) numerical method. Geometrical optics principles are applied to the scattered light to obtain the intensity distribution at the image plane. Multilayered object spaces are also supported by our algorithm. For the first time, numerical FDTD calculations are directly compared to and shown to agree well with broadband experimental microscopy results. 相似文献
69.
The reaction of 2‐(2‐bromoethyl)‐1,3‐dioxane with 1‐alkylbenzimidazole derivatives results in the formation of the new benzimidazolium salts (1). The reaction of Pd(OAc)2 with 1,3‐dialkylbenzimidazolium salts (1a–c) yields palladium N‐heterocyclic carbene (NHC) complexes (2a–c). All synthesized compounds were characterized by 1H NMR, 13 C NMR, IR and elemental analysis techniques which support the proposed structures. As catalysts, these new palladium complexes offer a simple and efficient methodology for the synthesis of triarylamines and secondary amines from anilines and amines and in a single step with potassium tertiary butoxide as a base. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
70.
Çiğdem Hopa Mahir Alkan Canan Kazak N. Burcu Arslan Raif Kurtaran 《Journal of chemical crystallography》2010,40(2):160-164