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71.
Cu(II) and Zn(II) complexes were synthesized from equimolar amounts of carboxamides; 1,8-bis(2-thiophenecarboxamido)-p-menthane (tkdam) and 1,8-bis(2-furancarboxamido)-p-menthane (furdam). The structure of the carboxamides were determined by elemental analysis; 1H NMR, 13C NMR, FT-IR and LC-MS spectra. The relative energies and the electronic properties (LUMO, HOMO, LUMO-HOMO gap) of the ligands
were investigated theoretically by performing Semi-empirical molecular orbital theory PM3 method in Hyperchem 7 (Release).
Carboxamide complexes having general formula as; monomeric, [ML]Cl2 and dimeric [Cu(tkdam)Cl]2Cl2 · 5H2O were synthesized and characterized by using element analysis; FT-IR, LC-MS spectra; magnetic susceptibility, molar conductivity
and thermal (TGA/DTA curve) studies. It was found that the coordination number of the monomeric complexes is four whereas
dimeric’s is six. The changes in the selected vibration bands in FT-IR indicate that, carboxamides behave as tetradentate
ligands and coordinate to metal ions from acyl ring (through S/O) and amide carbonyl (C=O). Molar conductivity measurements
indicate the 1: 2 ionic nature of the carboxamide complexes. 相似文献
72.
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
73.
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
74.
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
75.
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
76.
Çiğdem Hopa Mahir Alkan Canan Kazak N. Burcu Arslan Raif Kurtaran 《Journal of chemical crystallography》2010,40(2):160-164
Abstract
The dinuclear cadmium(II) complex with 2,6-bis(3,4,5-trimethyl-N-pyrazolyl)pyridine (btmpp) has been synthesized, and characterized by single crystal X-ray diffraction, IR, UV–Vis and TGA–DTA methods. Cd atoms are located in a distorted octahedral environment in the complex. The complex crystalizes in monoclinic space group C 2/c, with unit cell dimensions a = 20.5636(12) Å, b = 14.0167(13) Å, c = 15.6598(11) Å, β = 113.425(5)o, V = 4141.7(5) Å3. There are two intermolecular and a intramolecular hydrogen bonds interactions in crystal. 相似文献77.
Es wurde eine Laboreinrichtung zur kontiniuerlichen Aktivierungsanalyse strömender, Flüssigkeiten entworfen und gebaut. Die Einrichtung bestecht aus dem Vorratsbehälter für die Probelösung, der Aktivierungskammer, einer Pu-Be-Neutronenquelle, der Meβkammer, der Meβeinrichtung, einer Laborpumpe und einem Strömungsmesser. Die vorläufigen Versuche bewiesen, daβ mit der gebauten Einrichtung die Bestimmung von Vanadium, Silber and Kobalt möglich ist. 相似文献
78.
Nonlinear Dynamics - Substitution Box (S-Box) is one of the most significant structures used to create an encryption which is strong and resistant against attacks in block encryption algorithms.... 相似文献
79.
Synthesis and proton conductivity studies of polystyrene‐based triazole functional polymer membranes
Şehmus Özden Sevim Ünügür Çelik Ayhan Bozkurt 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):4974-4980
In this study, poly(vinylbenzylchloride) (PVBC) was produced by free‐radical polymerization of 4‐vinylbenzylchloride, and then it was functionalized with 3‐amino‐1,2,4‐triazole (ATri) and 1H‐1,2,4‐triazole (Tri). The composition of the polymers was verified by elemental analysis, and the structure was characterized by Fourier transform infrared and 13C‐nuclear magnetic resonance spectra. PVBC was modified by ATri with 68% and Tri with 50% yield. The polymers were doped with trifluoromethanesulfonic acid (TA) at various molar ratios, X = 0.5, 1, 2, and 3 with respect to aminotriazole and triazole units. Proton transfer from TA to the triazole rings was proved with Fourier transform infrared spectroscopy. Thermogravimetric analysis showed that the samples are thermally stable up to approximately 200 °C. Differential scanning calorimetry results illustrated the homogeneity of the materials. Under anhydrous conditions, PVBCATri3TA and PVBCTri3TA showed highest proton conductivity of 0.086 and 0.042 S/cm, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
80.
T. Ünak Z. Akgün Y. Duman Y. Yildirim U. Avcibaşi B. Çetinkaya 《Journal of Radioanalytical and Nuclear Chemistry》2003,256(3):529-534
Aniline-mustard and its glucuronide conjugate were radioiodinated with 131I. The preliminary dynamic tests were carried out on rabbits. The scintigrams showed clearly that the glucuronide conjugate of aniline-mustard was very quickly cleared from the metabolism, accumulating in the bladder in about 15 minutes. The clearance time of radioiodinated aniline-mustard-glucuronide was considerably longer (about 45 min.). The results obtained from the biodistributional studies have represented interesting differences between the metabolic details of radioiodinated compounds, and indicated that the glucuronide conjugate of aniline-mustard may be a promising radioiodinated prodrug, if verification of its selective accumulation in some kinds of tumor cells can be obtained. 相似文献