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61.
Bünyemin OUT Burcu TOPALOLU AKSOY Süreyya Ouz TÜMAY Ahmet ENOCAK Serkan YELOT 《Turkish Journal of Chemistry》2020,44(1):48
Phenoxy- and naphthoxy-substituted bisphenol-bridged cyclic phosphazenes were synthesized in 2 steps and their thermal, photophysical, and electrochemical properties were investigated. The structures of the cyclic phosphazene compounds were determined by ESI-MS mass spectrometry and 1 H, 13 C, and 31 P NMR spectroscopies. The photophysical studies of phenoxy- and naphthoxy-substituted bridged cyclophosphazenes were investigated by means of absorption and fluorescence spectroscopies in different solvents. Thermal and electrochemical properties of the target compounds were also studied. Furthermore, the excimer emissions through intramolecular interactions in solution and in solid state were investigated by fluorescence spectroscopy and the theoretical calculations were performed in detail using DFT. 相似文献
62.
Serkan Erdemir Mustafa Tabakci Mustafa Yilmaz 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(3-4):197-202
Herein the synthesis and extraction abilities of new d-/l-phenylalaninol substituted p-tert-butylcalix[4]arene triamide derivatives (3 and 4) towards amino acids are reported. These compounds (3 and 4) have been easily synthesized via aminolysis of p-tert-butylcalix[4]arene trimethylester (2) with d-/l-phenylalaninol in methanol-toluen solvent system at one step. The extraction properties of the prepared chiral calix[4]arene
triamide derivatives (3 and 4) towards some selected amino acid methylesters are studied by liquid–liquid extraction. Results show that these chiral calix[4]arene
triamide derivatives (3 and 4) exhibited a good affinity towards all amino acid species without any remarkably discrimination. 相似文献
63.
Enise Akoz Serkan Erdemir Mustafa Yilmaz 《Journal of inclusion phenomena and macrocyclic chemistry》2012,73(1-4):449-458
A series of novel the semicarbazone derivatives of calix[4]arene have been synthesized and then immobilized onto amino functionalized magnetic nanoparticles. Magnetic Fe3O4 nanoparticles were prepared by the chemical co-precipitation of Fe(III) and Fe(II) ions and the nanoparticles were modified directly by 3-aminopropyltriethoxy silane (APTES) to introduce reactive amine groups onto the particles’ surface. The characterization of the prepared compounds was made by FT-IR, elemental analysis, TGA/DTG and NMR techniques. The sorption properties of the new calix[4]arene based magnetic sorbents toward Cr(VI) ion were also studied. The results showed that the prepared magnetic nanoparticles were effective sorbents for the removal of Cr(VI) ion. Also, Langmuir and Freundlich isotherm models were applied for Cr(VI) ion sorption by using MN-C2 and it was found that the experimental data confirmed to Langmiur isotherm model. 相似文献
64.
Veysel T. Yilmaz Serkan Guney Omer Andac William T. A. Harrison 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):m427-m430
The title complexes [M(sac)2(mpy)2] [sac is saccharinate (C7H4NO3S) and mpy is 2‐pyridylmethanol (C6H7NO)], with M = ZnII and CdII, are isostructural and consist of neutral molecules. The ZnII or CdII cations are octahedrally coordinated by the two neutral mpy and two anionic sac ligands. The mpy ligand acts as a bidentate donor through the amine N and hydroxyl O atoms. The sac ligands exhibit an ambidentate coordination behaviour; one is N‐coordinated and the other is O‐coordinated within the same coordination octahedron. The crystal packing is determined by C—H?O‐type hydrogen bonding, as well as by weak py–py and sac–sac aromatic π–π‐stacking interactions. 相似文献
65.
We propose a sequential learning policy for ranking and selection problems, where we use a non-parametric procedure for estimating the value of a policy. Our estimation approach aggregates over a set of kernel functions in order to achieve a more consistent estimator. Each element in the kernel estimation set uses a different bandwidth to achieve better aggregation. The final estimate uses a weighting scheme with the inverse mean square errors of the kernel estimators as weights. This weighting scheme is shown to be optimal under independent kernel estimators. For choosing the measurement, we employ the knowledge gradient policy that relies on predictive distributions to calculate the optimal sampling point. Our method allows a setting where the beliefs are expected to be correlated but the correlation structure is unknown beforehand. Moreover, the proposed policy is shown to be asymptotically optimal. 相似文献
66.
67.
We have solved the Dirac equation with an anomalous moment Pauli-coupling exactly for a constant magnetic field and derived the general relativistic formulas for phase changes due to translational motion and spin rotations. We also give transmission and reflection coefficients, spin rotation for tunnelling and barrier penetration. For ultrarelativistic particles the spin rotation angle on the path of lengthL is equal to (2μB L/ħc)[1 +m 2 c 4/(E2-μ 2 B 2)].
相似文献68.
A. O. Barut 《Annalen der Physik》1988,500(1):31-36
Radiation theory is reformulated by reviving the interpretation of Ψ-waves as realistic material waves of electronic matter and the relation of this formulation to second quantized quantum field theory is discussed. 相似文献
69.
70.