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排序方式: 共有1415条查询结果,搜索用时 203 毫秒
91.
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
92.
Armaan GÜNSEL Aye USLUOLU Ahmet Turgut BLGL TOSUN Büra Gülnur ARABACI Meryem Nilüfer YARAIR 《Turkish Journal of Chemistry》2020,44(4):923
This work reports on dyeing of nylon/elastane fabric with water-soluble phthalocyanines ( 1-4 ) bearing quinoline 5-sulfonic acid substituents on the peripheral or nonperipheral positions and determining the antibacterial efficiency of the phthalocyanine compounds and the dyed nylon/elastane fabrics. The light, washing, water, perspiration, and rubbing fastness properties of nylon/elastane fabrics dyed with phthalocyanines were also determined. The results showed that all dyed fabrics showed very good wet fastness values. The lightfastness value of the nylon/elastane fabric dyed with phthalocyanine dye ( 1 ) showed a much better value than the others. Also, the antibacterial efficiencies of the dyed nylon fabrics and the dye compounds were investigated against a gram-negative ( Escherichia coli ) and a grampositive ( Staphylococcus aureus ) bacteria by using disc diffusion method. The results showed that the dyed nylon/elastane fabrics and the compounds exhibited antibacterial activities against both bacteria. 相似文献
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96.
The behavior of proton transfer facilitated by a novel thiazole derivative, N-methyl-4-(4-phenoxyphenyl)thiazol-2-amine (MPPT),
across the water/1,2-dichloroethane (1,2-DCE) interface was investigated electrochemically. The ionic partition diagram for
MPPT was obtained from interpretation of the cyclic voltammograms. The apparent partition coefficient of MPPT was evaluated
by the shaking-flask method under experimental conditions, while that for the protonated form of MPPT was calculated from
its transfer potential obtained from the ionic partition diagram. It was suggested that the mechanism for transfer of MPPT
across the water/1,2-DCE) interface depends on the pH of the aqueous phase. The parameters of the facilitated proton transfer
across the water/1,2-DCE interface were evaluated as a quantitative measure of its lipophilicity. 相似文献
97.
S. R. Garaeva Ahmet Alper Aydin Adnan Aydin Bahattin Yalçin P. A. Fatullaeva A. A. Medzhidov 《Russian Journal of Applied Chemistry》2010,83(1):97-101
Structure of products formed in polyethylene oxidation by nitric acid was studied by NMR, IR, and electronic absorption spectroscopies
and derivatography. 相似文献
98.
Ahmet Yildirim 《Meccanica》2010,45(1):1-6
He’s modified Lindstedt-Poincaré method is applied to nonlinear oscillatiors with fractional powers. Comparison of the obtained
results with exact solutions provides confirmation for the validity of He’s modified Lindstedt-Poincaré method. 相似文献
99.
Yusuf Öztürk Asım Egemen Yılmaz Evrim Çolak Ekmel Özbay 《Photonics and Nanostructures》2012,10(4):624-631
Planar metamaterials, which have incident to normal plane excitation unlike SRR-type structures and that are easily fabricated in multilayer form, have received great interest in recent years. In this paper, one-dimensional and polarization independent circular fishnet metamaterials and their equivalent discontinuous slab-pair modeling for tuning resonance frequencies are introduced. After the numerical and experimental demonstration of the inclusions, the standard retrieval characterization methods and the correspondent/related backward-wave propagation observation are realized in order to check the physical explanation mentioned in the paper. In addition, a detailed phase analysis is performed in order to demonstrate the application of the suggested structure as a phase compensator. 相似文献
100.
O. Çakır İ. T. Çakır H. Duran Yıldız R. Mehdiyev 《The European Physical Journal C - Particles and Fields》2008,56(4):537-543
We study the single production of fourth-family quarks through the process pp→Q′jX at the Large Hadron Collider (LHC). We have calculated the decay widths and branching ratios of the fourth-family quarks
(b′ and t′) in the mass range 300–800 GeV. The cross sections for the signal and background processes have been calculated in a Monte
Carlo framework. It is shown that the LHC can discover single t′ and b′ quarks if the CKM matrix elements |V
t′q
|,|V
qb′|≳0.01. 相似文献