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排序方式: 共有62条查询结果,搜索用时 164 毫秒
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Yüksel Tufan Nurcan Karacan J. Eric D. Davies 《Journal of inclusion phenomena and macrocyclic chemistry》1999,33(2):149-154
Four new clathrates of the formula M(Im)2Ni(CN)4·2·Dioxane (where M = Co, Ni, Cu, Cd; Im = Imidazole) have been prepared in powder form and their FT-IR and laser-Raman spectra are reported for the first time. These clathrates are analogues to the previously reported classical Hofmann type clathrates except for the copper clathrate. The Cu clathrate has different spectral features in comparison with its analogues due to the Jahn-Teller effect. 相似文献
3.
?zdemir ümmühan Karacan Nurcan ?entürk Ozan Sanlι Sert Sema U?ur Fadime 《Transition Metal Chemistry》2003,28(4):443-446
Five new complexes, [M(CO)5(apmsh)] [M = Cr; (1), Mo; (2), W; (3)], [Re(CO)4Br(apmsh)] (4) and [Mn(CO)3(apmsh)] (5) have been synthesized by the photochemical reaction of metal carbonyls [M(CO)6] (M = Cr, Mo and W), [Re(CO)5Br], and [Mn(CO)3Cp] with 2-hydroxyacetophenone methanesulfonylhydrazone (apmsh). The complexes have been characterized by elemental analysis, mass spectrometry, f.t.-i.r. and 1H spectroscopy. Spectroscopic studies show that apmsh behaves as a monodentate ligand coordinating via the imine N donor atom in [M(CO)5(apmsh)] (1–4) and as a tridentate ligand in (5). 相似文献
4.
Alpar Pöllnitz Sevil Irisli Cristian Silvestru Anca Silvestru 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):910-919
The new organophosphorus proligand (OPPh2)(O2SMe)NR (R = C6H3Pri 2–2,6) (3) was prepared as a white crystalline solid by reacting the lithiated compound Li[Ph2P(O)NR] with MeSO2Cl in a 1:1 molar ratio. The precursor Ph2P(O)NHR (1), as well as its thio analogue Ph2P(S)NHR (2), were obtained in the reaction between the lithiated amine RNHLi and the corresponding organophosphorus chloride. All compounds were characterized by multinuclear (1H, 13C, and 31P) NMR spectroscopy. The molecular structures of 1–3 were established by single-crystal X-ray diffraction. A zigzag polymeric chain is formed in the crystals of 1 and 2 by hydrogen N–H···X (X = O, S) bonding, while the crystal of 3 contains discrete monomeric units with a syn–syn conformation of the O?P(C)2–N–S(C)(?O)2 skeleton. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
5.
Nurcan Balci Levent Toppare Ural Akbulut Dietmar Stanke Manfred L. Hallensleben 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1727-1739
Abstract Electrically conducting polypyrrole grafts with poly[(methyl meth-acrylate)-co-(2-(N-pyrrolyl) ethyl methacrylate)] (PMMA-co-PEMA) were synthesized by constant potential electrolysis. Cyclic Voltammetry, DSC, TGA, SEM and elemental analysis were used in order to characterize the free standing films. Conductivities of the polymers were measured by a four-probe technique. 相似文献
6.
Alpar Sevgen 《Nuclear Physics A》1974,218(3):542-558
A microscopic dynamical model is used for the inelastic scattering of nucleons by deformed nuclei and the fluctuation cross sections are calculated. The case of weak absorption in all channels is considered so that the number of statistical assumptions is minimized. The results are compared with the Hauser-Feshbach expressions as regards the magnitude and structure. The partial width amplitudes calculated from the model are correlated, the simplest type of level-level correlations being due to the similar-channels effect (SCE). When the correlations are due to SCE alone, the following two results are obtained, (i) The fluctuation cross sections are increased over the Hauser-Feshbach estimates, for Γ ? D and Γ ? D, by a factor κ if the entrance and exit channels are similar. The numerical value of κ is found to be 3 for a special case and in the general case it is conjectured to lie between the limits 1 and 3, (ii) The fluctuation cross sections σcc′f1 and σf1cc″ exhibit correlated fluctuations if the exit channels c′ and c″ are similar. The fluctuation cross sections in the cases “SCE+direct channel-channel coupling” and “SCE+intermediate structure” are also investigated. In all cases studied direct reaction cross sections do not vanish and the channelwise factorization assumption of the Hauser-Feshbach theory fails. 相似文献
7.
This paper compares three different approaches to scheduling in a closed-shop environment, making the case for a knowledge-based approach. A manufacturing example from the food industry is used as a vehicle for the presentation. The first approach attempts to find an optimal solution using a mixed integer linear programming formulation, but the size of the problem renders this approach impractical. The second approach uses a spreadsheet program to obtain feasible solutions, but imbedded assumptions in the heuristics used allow it to be used only for simple demand patterns. The third approach employs expert systems technology. It includes several heuristics and takes all constraints into consideration. The solution obtained may not be optimal, but computational tests suggest that it is far superior to both spreadsheet and manual approaches. 相似文献
8.
Nurcan Kurtoglu Mehmet Aslantaş Huseyin Zengin Ertan Şahin Mukerrem Kurtoglu 《Chemical Papers》2010,64(5):645-651
This study focuses on the preparation, single crystal X-ray diffraction, characterization, and optical properties of some
anthraquinone-based dyes. The anthraquinone-based antimicrobial dye N-{2-[(9,10-dioxo-9,10-dihydroanthracen-1-yl)amino]-2-oxoethyl}-N,N-dimethylbutan-1-aminium chloride monohydrate (III) was obtained from 1-aminoanthraquinone (I) via 2-chloro-N-(9,10-dioxo-9,10-dihydroanthracen-1-yl)acetamide (II) using known preparation and characterization methods. Single crystal X-ray diffraction analysis of III revealed a monoclinic system, space group P21/n, Z = 4. Photoluminescence properties of anthraquinone dyes I–III were also investigated. These dyes gave an intense emission (λmax = 341 nm) upon the irradiation by UV light and showed photoluminescence quantum yields of 73 %, 66 %, and 61 % with long
excited-state lifetimes of 6.87 ns, 6.14 ns, and 5.69 ns, respectively. These anthraquinone dyes are of interest as an organic
light emitting material for electroluminescent devices. 相似文献
9.
Gokhan Temel Nurcan Karaca Nergis Arsu 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5306-5312
Main chain polymeric benzophenone photoinitiator (PBP) was synthesized by using “Thiol‐ene Click Chemistry” and characterized with 1H NMR, FTIR, UV, and phosphorescence spectroscopies. PBP as a polymeric photoinitiator presented excellent absorption properties (ε294 = 28,300 mol?1L?1cm?1) compared to the molecular initiator BP (ε252 = 16,600 mol?1L?1cm?1). The triplet energy of PBP was obtained from the phosphorescence measurement in 2‐methyl tetrahydrofurane at 77 K as 298.3 kJ/mol and according to phosphorescence lifetime, the lowest triplet state of PBP has an n‐π* nature. Triplet–triplet absorption spectrum of PBP at 550 nm following laser excitation (355 nm) were recorded and triplet lifetime of PBP was found as 250 ns. The photoinitiation efficiency of PBP was determined for the polymerization of Hexanedioldiacrylate (HDDA) with PBP and BP in the presence of a coinitiator namely, N‐methyldiethanolamine (MDEA) by Photo‐DSC. The initiation efficiency of PBP for polymerization of HDDA is much higher than for the formulation consisting of BP. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
10.
Beleaga A Bojan VR Pöllnitz A Raţ CI Silvestru C 《Dalton transactions (Cambridge, England : 2003)》2011,40(35):8830-8838
The reaction of RH (1) with Hg(OAc)(2), in EtOH, gave the acetate RHgOAc (2) [R = 2,6-[O(CH(2)CH(2))(2)NCH(2)](2)C(6)H(3)]. The corresponding RHgCl (3) was obtained from 2 and LiCl. The reaction of 3 with TeCl(4) (1:1 molar ratio), in anhydrous 1,4-dioxane, resulted in the transfer of the organic ligand from mercury to tellurium and the isolation of the unexpected ionic compounds [RTe](2)[Hg(2)Cl(6)] (4) and [RH(3)][HgCl(4)] (5). The molecular structures of 1-4 and 5·H(2)O were established by single-crystal X-ray diffraction. The acetate 2 and the chloride 3 are monomeric in solid state. In both mercury and tellurium organometallic compounds the organic group acts as an (N,C,N) "pincer" ligand. This coordination pattern provided stability for the rare [RTe](+) cation. Weak cation-anion interactions [Te···Cl 3.869(3) ?] are present between [RTe](+) and the dinuclear anion [Hg(2)Cl(6)](2-) in the crystal of 4. Theoretical calculations with DFT methods were performed for models of 3 and 4. The results show that in the cation of 4 the coordination of the nitrogen atoms play an important role for the stabilization of the structure found in the crystal whereas in 3 the coordination of the nitrogen atoms to the metal centre stabilizes to a less extent the structure found in solid state. 相似文献