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81.
82.
Ismail Ercan Filiz Ercan Cengiz Arc Orhan Atakol 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):m137-m138
A new tetranuclear CuII–HgII–HgII–CuII complex, [Cu2Hg2Cl4(C18H18N2O2)2], has been prepared by means of a copper complex found in the literature. The molecular structure of this complex was determined by X‐ray diffraction and the Cu–Hg–Hg–Cu chain was seen to be non‐linear. The change in magnetic susceptibility with temperature was recorded for this complex and observed to abide by the Curie–Weiss law. The coordination around the HgII ions is square pyramidal. The Cu?Hg bridging distance is 3.5269 (7) Å. 相似文献
83.
A comparative study on the efficiency of some tungsten containing chemical modifiers such as W, W+Pd, W+Rh, W+Pt and W+Ru
for thermal stabilization of Bi, In, Pb and Sb has been performed systematically by a Zeeman electrothermal atomization atomic
absorption spectrometer (ETAAS). The addition of tartaric acid (TA) as a reducing agent additionally to the mixed modifiers
was studied. A mixture of W+Pd+TA was found to be a powerful mixed modifier for the determination of Bi, In, Pb and Sb. Pretreatment
temperatures could be increased up to 1250–1500° C using this mixed modifier. The use of the mixed modifier results in an
enhanced accuracy and precision of the method and recovery rates above 97% for all samples. The W+Pd+TA mixed modifier was
applied to the determination of Bi and Pb in dissolved geological reference samples.
Received: 14 March 1996 / Revised: 3 June 1996 / Accepted: 30 June 1996 相似文献
84.
Onur ahin Orhan Büyükgüngr Selami amaz Nurhan Gümrüküolu Cihan Kantar 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(7):o431-o433
The title compound, C6H12N4, has four crystallographically independent molecules in the asymmetric unit. Intermolecular N—H...N hydrogen bonds involving amino groups and triazole N atoms form a three‐dimensional framework involving R44(10) and R44(20) rings. The hydrogen bonding is supported by weak C—H...π interactions. 相似文献
85.
Orhan Acar A. Rehber Türker Ziya Kl? 《Fresenius' Journal of Analytical Chemistry》1997,357(6):656-660
A comparative study on the efficiency of some tungsten containing chemical modifiers such as W, W+Pd, W+Rh, W+Pt and W+Ru
for thermal stabilization of Bi, In, Pb and Sb has been performed systematically by a Zeeman electrothermal atomization atomic
absorption spectrometer (ETAAS). The addition of tartaric acid (TA) as a reducing agent additionally to the mixed modifiers
was studied. A mixture of W+Pd+TA was found to be a powerful mixed modifier for the determination of Bi, In, Pb and Sb. Pretreatment
temperatures could be increased up to 1250–1500° C using this mixed modifier. The use of the mixed modifier results in an
enhanced accuracy and precision of the method and recovery rates above 97% for all samples. The W+Pd+TA mixed modifier was
applied to the determination of Bi and Pb in dissolved geological reference samples.
Received: 14 March 1996 / Revised: 3 June 1996 / Accepted: 30 June 1996 相似文献
86.
Orhan Özdemir Mustafa Anutgan Tamila Aliyeva-Anutgan İsmail Atılgan Bayram Katırcıoğlu 《Journal of Non》2009,355(14-15):851-859
Both dc and ac transport characteristics of plasma enhanced chemical vapor deposited (PECVD) boron nitride (BN) thin film was investigated by dc current vs. dc voltage measurement at different temperatures and admittance vs. gate voltage at various frequencies/temperatures, respectively. MIM ≡ metal (Al)-insulator (BN)-metal (Al) or MIS ≡ metal (Al)-BN-semiconductor (p-Silicon) test devices were conventionally produced. Both conductivity anisotropy and dc/ac detailed transport mechanism were analyzed within the frame of a turbostratic structure (t-BN), interfacing the substrate by a thin amorphous layer (a-BN). This defective BN film has been justified by both infrared (IR) analysis and indirectly by the resulting electrical transport behavior. Transport and its variations as a function of temperature/frequency are in agreement with a hopping mechanism across Gauss-like energy distributed localized deep traps. 相似文献
87.
Hümeyra Paaolu Ahmet Karada Fatma Tezcan Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):m93-m94
In the novel transition metal isothiocyanate complex of N‐(2‐hydroxyethyl)ethylenediamine (hydet‐en) with copper, [Cu(NCS)2(C4H12N2O)], the Cu atom lies in a distorted square‐pyramidal environment, coordinated by four N atoms in the basal plane and an apical O atom. The hydet‐en ligand is N,N,O‐tridentate, in contrast to the disposition in previously studied complexes, while the isothiocyanate ions act as N‐atom donor ligands. The monomeric units are linked to one another by hydrogen bonds. 相似文献
88.
(2,9‐Dimethyl‐1,10‐phenanthroline‐κ2N,N′)(pyridine‐2,6‐dicarboxylato‐κ3O2,N,O6)copper(II) trihydrate
Ibrahim Uar Ahmet Bulut Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):m479-m481
The copper(II) centre in the mononuclear title complex, [Cu(C7H3NO4)(C14H12N2)]·3H2O, is surrounded by one bidentate 2,9‐dimethyl‐1,10‐phenanthroline (dmphen) ligand and one tridentate pyridine‐2,6‐dicarboxylate ligand, and exhibits a distorted square‐pyramidal geometry. The crystal packing involves both hydrogen‐bonding and π–π interactions. The solvent water molecules link monomers to one another through hydrogen‐bonding interactions, forming ladder‐like chains in the bc plane. Face‐to‐face and slipped π–π interactions also occur between dmphen rings of neighboring molecules and are responsible for interchain packing. 相似文献
89.
Three novel Cu(II)-pyrazine-2,3-dicarboxylate complexes with 1,3-propanediamine (pen), [Cu2(μ-pzdc)2(pen)2] · 2H2O (1), N,N,N′,N′-tetramethylethylenediamine (tmen), {[Cu(μ-pzdc)(tmen)] · H2O}n(2), and 2,2′-bipyridine (bipy), {[Cu(μ-pzdc)(bipy)]·H2O}n(3) have been synthesized and characterized by means of elemental and thermal analyses, magnetic susceptibilities, IR and UV/vis spectroscopic studies. The molecular structures of dinuclear (1) and polynuclear (2 and 3) complexes have been determined by the single crystal X-ray diffraction technique. The pyrazine-2,3-dicarboxylate acts as a bridging ligand through oxygen atom of carboxylate group and N atom of pyrazine ring and one oxygen atom of neighboring carboxylate. It links the Cu(II) ions to generate a distorted square pyramidal geometry forming a one-dimensional (1D) chain. Adjacent chains of 1 and 2 are then mutually linked via hydrogen bonding interactions, which are further assembled to form a two and three-dimensional network, respectively. The chains of complex 3 are further constructed to form three-dimensional framework by hydrogen bonding, C–H?π and ring?ring stacking interactions. In the complexes, Cu(II) ions have distorted square pyramidal geometry. Thermal analyses properties and thermal decomposition mechanism of complexes have been investigated by using thermal analyses techniques (TG, DTG and DTA). 相似文献
90.
Emine Özge Karaca Nevin Gürbüz Onur Şahin Orhan Büyükgüngör İsmail Özdemir 《应用有机金属化学》2016,30(12):1050-1055
N‐Aryl amination and the Buchwald–Hartwig reaction are of great synthetic and industrial interest and scientists accept their usefulness and versatility for obtaining arylamines. In this study Ag–N‐heterocyclic carbene complexes were used as transmetallation reagents for the synthesis of Pd–N‐heterocyclic carbene complexes. The new Pd–N‐heterocyclic carbene complexes were characterized using elemental analysis and 1H NMR, 13C NMR and infrared spectroscopies. The crystal structure of one, namely dichlorobis[1,3‐bis(2‐methylbenzyl)imidazolidin‐2‐yliden]palladium(II), is presented. The activity of the Pd(II) complexes in the coupling reaction of anilines or amines with bromobenzene was investigated. These complexes exhibited high catalytic activities in the direct synthesis of triarylamines and secondary amines in a single step. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献