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31.
Güneş Süheyla Kürkçüoğlu Dr. Okan Zafer Yeşilel Ilkan Kavlak Orhan Büyükgüngör 《无机化学与普通化学杂志》2009,635(1):175-178
The heteronuclear polymeric complex, [Zn(teta)Ni(μ‐CN)2(CN)2]n (teta: triethylenetetramine), was synthesized and characterized by elementel analysis, FT‐IR spectroscopy, thermal analysis and single crystal X–ray diffraction techniques. The complex crystallizes in the monoclinic system, space group P21/c and in which the ZnII ion exhibits a distorted octahedral coordination by one tetradentate teta ligand and two bridging cyano groups as a trans position, whereas the NiII ion has square planer coordination and is coordinated by four cyano ligands. The decomposition reaction takes places in the temperature range 30–600 °C in the static air atmosphere. 相似文献
32.
Okan Zafer Yeşilel Prof. Dr. Hakan Erer Necmi Dege Orhan Büyükgüngör 《无机化学与普通化学杂志》2009,635(3):577-581
Two nickel(II) complexes of vitamin B13 (H3Or) with N,N,N′,N′‐tetramethylethylenediamine (tmen) and 2,2‐dimethylpropane‐1,3‐diamine (dmpen) were synthesized and characterized by means of elemental and thermal analyses, magnetic susceptibility, and IR and UV/Vis spectroscopic studies. The crystal structures of mer‐[Ni(HOr)(H2O)2(tmen)] · H2O ( 1 ) and [Ni(HOr)(dmpen)2] ( 2 ) were determined by using single‐crystal X‐ray diffraction. In the complexes, which crystallize in the triclinic system (space group for 1 ) and the monoclinic system (space group P21/c for 2 ), the NiII ions exhibit a distorted octahedral coordination. NiII ions are chelated by the deprotonated nitrogen atom of the pyrimidine ring and the oxygen atom of the carboxylate group, the distorted octahedral coordination completed by one tmen and two aqua ligands for 1 or two dmpen ligands for 2 . 相似文献
33.
A Riesz space E is said to have b-property if each subset which is order bounded in E~~ is order bounded in E. The relationship between b-property and completeness, being a retract and the absolute weak topology |σ|(E~, E) is studied. Perfect Riesz spaces are characterized in terms of b-property. It is shown that b-property coincides with the Levi property in Dedekind complete Frechet lattices.
相似文献
34.
In this work, we establish a methodology for comparing the efficiencies of different hydrazide labels for detecting protein carbonyls. We have chosen acrolein-modified human serum albumin as a model. This system provides a convenient means of reproducibly generating carbonylated protein. Five hydrazide-based labels were tested. Three carry a biotin affinity tag, and the others are simple fatty acid hydrazides. For the biotin-based labels, the yield of the labeling reaction varies considerably, and the most commonly used label, biotin hydrazide, gives the lowest yield. The total tandem mass spectrometry (MS/MS) spectrum counts of modified peptides are similar for all of the biotin-based tags, indicating that factors beyond the labeling efficiency are important in determining the effectiveness of the label. In addition, there is a large variation in the number of spectra obtained for specific, modified peptides depending on the nature of the labeling group. This variation implies that the relative detectability of a particular modification site is highly dependent on the tagging reagent, and more importantly, titration schemes aimed at identifying the most reactive site based on its threshold concentration will be biased by the choice of tagging reagent. The fatty acid hydrazides are somewhat more effective than the biotin-based hydrazides in generating identifiable MS/MS spectra but offer no opportunity for enrichment. For the biotin-based tags, avidin affinity chromatography was used with the tryptic digests, and each tag led to similar enrichment levels. 相似文献
35.
Aybüke A. ?sbir-Turan Emine K?l?? Zafer üstünda? Haslet Ek?i Ali Osman Solak Betül Zorer 《Journal of Solid State Electrochemistry》2012,16(1):235-245
The goal of this study was to prepare novel glassy carbon electrode surfaces using two similar bis-diazonium salts, 3,8-benzo[c]cinnoline (3,8-BCC-BDAS) and 3,8-benzo[c]cinnoline 5-oxide (3,8-BCCNO-BDAS) at the glassy carbon (GC) surface. These diazonium salts were reduced electrochemically
and covalently electrografted onto the glassy carbon electrode surface to form modified electrodes. Electrochemical reduction
of 3,8-BCC-BDAS and 3,8-BCCNO-BDAS salts on the electrode surface yielded a compact and stable film. The existence of BCC
moieties on the GC surface was characterized by X-ray photoelectron spectroscopy, reflectance-adsorption infrared spectroscopy,
cyclic voltammetry, ellipsometry, and electrochemical impedance spectroscopy. The stability and working potential range of
the novel modified electrodes were also studied. The possibility of analytical application of these novel surfaces for inorganic
cations and especially selectivity to copper ions was investigated. 3,8-diaminobenzo[c]cinnoline (3,8-DABCC) and its 5-oxide derivative (3,8-DABCCNO) were synthesized from the reductive cyclization of 2,2′-dinitrobenzidine
and prepared their bisdiazonium salts via the tetrazotization reactions of the diamines with NaNO2. The structures of 3,8-DABCC and 3,8-DABCCNO and their corresponding bisdiazonium salts are confirmed by spectral analysis. 相似文献
36.
Secil Tekin-Celebi Ali Osman Solak Zafer Ustundag Serkan Demirci 《Chemical Papers》2012,66(12):1146-1156
Acidity constant values of benzoic acid (BA)-modified platinum electrode (Pt-BA) and p-aminobenzoic acid (pABA)-modified platinum electrode (Pt-NHBA) surfaces were determined using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and contact angle measurements (CAM). Diazonium tetrafluoroborate salt reduction and pABA oxidation reactions were used to prepare (Pt-BA) and (Pt-NHBA) surfaces, respectively. Both surfaces exhibited pH dependence with [Fe(CN)6]3?/4? redox probe solutions at different pH; this allowed us to estimate the surface pK a values. Acidity constants for Pt-BA surface were found to be pK a (3.09 ± 0.25), (4.89 ± 0.11), and (3.91 ± 0.54) by CV, EIS, and CAM techniques, respectively, while the values for Pt-NHBA surface were pK a (3.16 ± 0.45), (4.24 ± 0.40), and (5.64 ± 0.12). The Pt-BA surface pK a values were lower in CV and CAM measurements relative to the bulk solution of BA, while a higher value was observed in EIS for Pt-BA surface. The pK a values determined for Pt-NHBA surface via both CV and EIS were lower than the bulk value; however, the result obtained from CAM was one unit higher than pK a of bulk pABA. 相似文献
37.
?lkay Çayl?Güne? Süheyla Kürkçüo?lu Okan Zafer Ye?ilelOnur ?ahin Orhan Büyükgüngör 《Polyhedron》2012,31(1):386-394
Three new heterometallic complexes, [Cu(N-Meim)4Pd(μ-CN)2(CN)2]n (1), [Zn(N-Meim)3Pd(μ-CN)2(CN)2]n (2) and [Cd(N-Meim)2Pd(μ-CN)4]n (3), have been isolated from the reactions of M[Pd(CN)4] (M = Cu(II), Zn(II) or Cd(II)) and N-Meim (N-methylimidazole) with in different molar ratios. All complexes have been characterized by X-ray analyses, vibrational (FT-IR and Raman) spectra, thermal and elemental analyses. The crystallographic analysis reveals that the crystal structures of 1 and 2 are 1D coordination polymer, while 3 presents a 2D network. In the Cu(II) and Zn(II) complexes, two cyanide groups of [Pd(CN)4]2− coordinated to the adjacent M(II) ions and distorted octahedral and square pyramidal geometries of complexes are completed by four and three nitrogen atoms of N-Meim ligands, respectively. The Cd(II) ion is six-coordinate, completed with the two nitrogen atoms of N-Meim ligands in the axial positions and the four nitrogen atoms from bridging cyano groups in the equatorial plane. The most striking features of complexes 1-3 are the presence of obvious C-H?Pd hydrogen-bonding interactions between the Pd(II) and hydrogen atoms of N-Meim ligand. This weak hydrogen bonding plays a crucial role in the architecture of the network polymers. The adjacent chains are held together by C-H?Pd, C-H?π or π?π interactions, forming three-dimensional network. 相似文献
38.
Şadan Korkmaz Saliha Elmas Naci Ekem Suat Pat M. Zafer Balbağ 《Optics Communications》2012,285(9):2373-2376
In this study, optical and surface properties of MgF2 thin films produced by thermionic vacuum arc (TVA) technique have been investigated. By means of this technique the MgF2 thin film produced by condensing the plasma of anode material generated by using TVA under high vacuum conditions on the glass. The optical properties have been investigated by using Filmetrics F20 and UV/VIS spectrometer. For surface properties of produced thin films EDS, SEM and AFM have been used. Our analysis shows that MgF2 thin films produced by using TVA are proper single and multi layer anti-reflective (AR) coating and TVA technique brings very important advantages for ophthalmic glass coating and industrial applications' optical purposes. 相似文献
39.
Alper Tolga ?olak G?nül Pamuk Okan Zafer Ye?ilel Filiz Y?lmaz Orhan Büyükgüng?r 《Journal of chemical crystallography》2012,42(1):76-82
Abstract
The [Co(H2O)6][Co(pydc)2(en)]2·14H2O (1) compound (H2pydc = Pyridine-2,3-dicarboxylic acid and en = ethylenediamine) was synthesized and characterized by elemental analysis, magnetic and spectroscopic measurements (UV–Vis and IR spectra) and single crystal X-ray diffraction technique. There are two coordination spheres with different charges inside this aqueous compound of ionic character. The cationic part is composed of Co(II) encircled by six aqua ligand. Whereas the anionic part contains two anions complex unit each with −1 charge and have Co(III) ions in the centre. As a result different coordination spheres have cobalt ions with different states. The crystallographic analysis revealed that 1 consists of both discrete one-cationic and two-anionic entities, [Co(H2O)6]2+ and [Co(pydc)2(en)]2− and fourteen crystal water molecules. Two water molecules within the water cluster act as hydrogen-bonding acceptors, whereas one water molecule acts as a hydrogen-bonding donor to form a discrete water trimer. These water molecules have stabilized the crystal structure by strong hydrogen bonding interactions. 相似文献40.
Ağacık Zafer 《Journal of Mathematical Analysis and Applications》2012,396(2):606-617
In this paper, we first establish new Lyapunov type inequalities for discrete planar linear Hamiltonian systems. Next, by making use of the inequalities, we derive stability and disconjugacy criteria. Stability criteria are obtained with the help of the Floquet theory, so the system is assumed to be periodic in that case. 相似文献