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31.
Nermin E. Maysour 《Journal of Dispersion Science and Technology》2013,34(8):1287-1298
Poly (ethylene terephthalate), PET, waste was recycled to oligomers in the presence of triethanolamine and manganese acetate as a catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol having different molecular weights 400, 1000, and 4000 to produce nonionic polymeric surfactants having different hydrophile‐hydrophobe balances (HLB). The surface tension, critical micelle concentration (CMC) and surface activities were determined at different temperatures. Surface parameters such as, surface excess concentration Γmax, the area per molecule at interface Amin and the effectiveness of surface tension reduction (ΠCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process are calculated and discussed. 相似文献
32.
Recycling of PET waste was carried out in presence of diethanolamine and manganese acetate as catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol, PEG, which have different molecular weights 400, 1,000, and 4,000 to produce nonionic polymeric surfactants having different hydrophilic‐hydrophobic balance (HLB). The surface tension, critical micelle concentration (CMC), and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration Γmax, the area per molecule at interface Amin and the effectiveness of surface tension reduction (ΠCMC) were determined from the adsorption isotherms of the prepared surfactants. From the adsorption isotherm, some thermodynamic data for the adsorption process are calculated and discussed. 相似文献
33.
Seyrek E Hierrezuelo J Sadeghpour A Szilagyi I Borkovec M 《Physical chemistry chemical physics : PCCP》2011,13(28):12716-12719
Highly charged polyelectrolytes adsorbed on oppositely charged colloidal particles are investigated by electrophoresis and dynamic light scattering. The dependence of the adsorbed amount and of the hydrodynamic layer thickness on the molecular mass and the salt level is analyzed. The adsorbed amount increases with increasing salt level and decreases with increasing molecular mass. The hydrodynamic layer thickness is independent of the molecular mass at low salt levels, but increases with the molecular mass as a power law with an exponent 0.10 ± 0.01 at high salt. The same behavior was observed for different polyelectrolytes and substrates and therefore is suspected to be generic. Due to semi-quantitative agreement with computer simulations carried out by Kong and Muthukumar in 1998, the observed behavior is interpreted with conformational changes of single adsorbed polyelectrolyte chains. 相似文献
34.
The application of tunable tridendate P‐based ligands for the Ru(II)‐catalysed transfer hydrogenation of various ketones
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Two novel versatile tridendate aminophosphine–phosphinite and phosphinite ligands were prepared and their trinuclear neutral ruthenium(II) dichloro complexes were found to be effective catalysts for the transfer hydrogenation of various ketones in excellent conversions up to 99% in the presence of 2‐propanol/NaOH in 0.1 M isopropanol solution. Particularly, [Ru3(PPh2OC2H4)2 N–PPh2(η6‐p‐cymene)3Cl6] acts as an excellent catalyst giving the corresponding alcohols in excellent conversion up to 99% (turnover frequency ≤ 1176 h?1). A comparison of the catalytic properties of the complexes is also discussed briefly. Furthermore, the structures of these ligands and their corresponding complexes have also been clarified using a combination of multinuclear NMR spectroscopy, infrared spectroscopy and elemental analysis. 1H–13C HETCOR or 1H–1H COSY correlation experiments were used to confirm the spectral assignments. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
35.
Nermin Doğan Süheyla Özbey Mehmet Karakaplan Tarık Aral 《Journal of chemical crystallography》2008,38(12):943-947
Abstract The crystal and molecular structure of chiral crown ether, (S)-2-[(4-methoxyphenoxy)methyl]-15-crown-5 · NaClO4, has been determined by single-crystal X-ray diffraction. The complex crystallizes in the orthorombic space group Pbca with
Z = 8. Lattice parameters are a = 11.451(2), b = 12.842(3), c = 31.330(7) ?. The structure was refined to R factor of 0.0547.
The Na ion is heptacoordinated. The Na–Oether distances range from 2.363(4) to 2.433(4) ? and average 2.404(5) ?. Perchlorate anion is bounded to sodium ion asymmetrically;
the Na–O8 and Na–O9 distances are 2.444(5) ? and 2.607(5) ?. The C–O and C–C distances of the 15-membered ring average 1.419(9)
and 1.478(12) ? while the O–C–C and C–O–C angles average 108.2(6)˚ and 115.4(6)˚.
Index Abstract In the molecule, the sodium ion is seven coordinated by the five ring oxygen atoms and two oxygen atoms of the perchlorate
anion. The macrocyclic strand of the molecule displays ag-a, ag+a, ag−a, ag+a, ag−g-set of torsion angles.
相似文献
36.
Nermin Kasapoglu Bahar Birsöz Abdülhadi Baykal Yüksel Köseoglu Muhammet S. Toprak 《Central European Journal of Chemistry》2007,5(2):570-580
A series of Ni doped cobalt ferrite compounds with the formula Ni
χ
Co1−χ
Fe2O4 where x=0, 0.2, 0.4, 0.6, 0.8, and 1.0 were prepared using a hydrothermal method and subsequently sintered/annealed at 600
°C for 3 h. The influence of the Ni content on the lattice parameter, a, stretching vibration and the magnetization of specimens were subsequently studied. XRD and FTIR were used to investigate
structure and composition variations. All samples were found to have a cubic spinel structure. SEM was used to study morphological
variations. The results indicate that the average particle sizes are between 30–35 nm with a narrow size distribution along
with nanocrystals forming of regular octahedrons. A decrease in the peak to peak line width and increase in resonance field
with increasing Ni content were observed from ESR measurements. Based on ESR results, a core-shell type of formation was proposed
where the core is made up of undoped CoFe2O4 and the shell is Ni2+ doped CoFe2O4.
相似文献
37.
Six new multidentate bis(diphenyl‐phosphino)amine [R–N(PPh2)2] ligands have been prepared from the reaction of aniline derivatives, R–NH2, with Ph2PCl in the presence of triethylamine. All of the compounds were obtained in good yields and were characterized by NMR, IR, and microanalysis. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:613–616, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20362 相似文献
38.
Yaser W. Abdlhmed Al‐bayati Duygu Elma Karakaş Nermin Meriç Murat Aydemir Feyyaz Durap Akın Baysal 《应用有机金属化学》2018,32(1)
In the present study, a series of chiral C2‐symmetric ferrocenyl based binuclear η6‐benzene‐Ru(II) complexes bearing diphenylphosphinite and diisopropylphosphinite moieties have been synthesised. The new binuclear η6‐benzene‐Ru(II)‐phosphinite complexes were characterised based on nuclear magnetic resonance (1H, 13C, 31P–NMR), FT‐IR spectroscopy and elemental analysis. Then, these complexes have been screened as catalytic precursors in the transfer hydrogenation of acetophenone with 2‐propanol as both the hydrogen source and solvent in the presence of KOH. The corresponding optically active secondary alcohols were obtained in excellent conversion rates between 96 and 99% and moderate to good enantioselectivities (up to 78% ee). The complex 5 was the most efficient catalyst among the four new complexes investigated herein. 相似文献
39.
Murat Aydemir Nermin Meric Akin Baysal Yilmaz Turgut Cezmi Kayan Sevil ?eker Mahmut To?rul Bahattin Gümgüm 《Journal of organometallic chemistry》2011,696(8):1541-1546
Enantioselective reduction of prochiral ketones to optically active secondary alcohols is an important subject in synthetic organic chemistry because the resulting chiral alcohols are extremely useful, biologically active compounds. The new chiral ligands (2R)-2-[benzyl{(2-((diphenylphosphanyl)oxy)ethyl)}amino]butyldiphenylphosphinite, 1 and (2R)-2-[benzyl{(2-((dicyclohexylphosphanyl)oxy)ethyl)}amino]butyldicyclohexylphosphinite, 2 and the corresponding ruthenium(II) complexes 3 and 4 have been prepared. The structures of these complexes have been elucidated by a combination of multinuclear NMR spectroscopy, IR spectroscopy and elemental analysis. 31P-{1H} NMR, DEPT, 1H-13C HETCOR or 1H-1H COSY correlation experiments were used to confirm the spectral assignments. These ruthenium(II)-phosphinite complexes have been used as catalysts for the asymmetric transfer hydrogenation of acetophenone derivatives. Under optimized conditions, aromatic ketones were reduced in good conversions and in moderate to good enantioselectivities (up to 85% ee). 相似文献
40.
Bahattin Gümgüm Nermin Bırıcık Akın Baysal 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2507-2512
Microwave heating technique was applied to the preparation of dialkyl dithiophosphoric acids from the reaction of alcohol with phosphorus pentasulphide. A microwave oven (CEM-MDS 2000) was utilized to determine the preparation conditions for the best yield of dialkyl dithiophosphoric acids under atmospheric pressure at various times and power. Six different (C 4 -C 9 ) chain-length of dialkyl dithiophosphoric acids were studied. All experiments were performed in an open Teflon (poly-tetrafluoroethylene) vessel. The results obtained showed that the reaction of dialkyl dithiophosphoric acids can be achieved more rapidly using microwave heating than using conventional procedures. 相似文献