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241.
In this paper, we consider the strongly quotient graphs and obtain some better results for the energy and Estrada index of
these graphs, as well as some relations between Estrada index and the graph energy. 相似文献
242.
In the present work, octachlorocyclotetraphosphazatetraene (1), N4P4Cl8, is reacted with aniline (2), 1-napthylamine (4) and 2-aminoanthracene (6) to give octakis(arylamino)cyclotetraphosphazenes (3, 5 and 7). These cyclotetraphosphazene compounds (3, 5 and 7) have been fully characterized by elemental analysis, mass (MS), FT-IR, 1H and 31P NMR spectroscopies. The molecular and crystal structures of 5 have been characterized by X-ray crystallography. The structure of 5 is monoclinic with the space group P21/c. The octakis(1-napthylamino)-(5) and octakis(2-aminoanthracene)-(7) cyclotetraphosphazene compounds have been synthesised for the first time in this study. The fluorescence properties of 3, 5 and 7 have been investigated in tetrahydrofuran (THF) and have been shown to have highly fluorescence behavior. This work also presents the quenching of arylamino substituted cyclotetraphosphazene derivatives (3, 5 and 7) by p-benzoquinone (BQ) or hydroquinone (HQ). 相似文献
243.
Merdivan E Benibol Y Seyhan S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,71(5):2045-2049
Mixtures of boron and azomethine-H in solution result in slow complexation. Addition of sodium dodecyl sulfate (SDS), polyethylene glycol dodecyl ether (Brij-35), 4-(1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol (TritonX-100), and cetyltrimethyl ammonium bromide (CTAB) result in considerable decrease in complexation time and enhancement in signal of peak in solution and also sol-gel. The fluorescence of the complex is monitored at an emission wavelength of 486 nm with excitation at 416 nm. The presence of 1x10(-3) mol L(-1) SDS decreased the complexation time up to 10 min in solution and 20 min in sol-gel for above 0.25 microg B mL(-1) and 30 min in solution and 35 min in sol-gel for below 0.25 microg B mL(-1). However, the photostability did not change by adding micelle in both media. The proposed method shows a linear response toward boron in the concentration range of 0.05-10 microg mL(-1) and is selective for boron over a large number of electrolytes and cations. The detection limit was 7 microg L(-1). This method has been used for the detection of boron in environmental water samples and fruit juices with satisfactory results. 相似文献
244.
Gökhan Ceyhan Mehmet Tümer Muhammet Köse Vickie McKee Seyhan Akar 《Journal of luminescence》2012,132(11):2917-2928
In this study, we prepared two Schiff base ligands N-(4-hydroxy phenyl)-2,4-di-methoxy benzaldimine (TS1) and N-(4-hydroxy phenyl)-2,5-di-methoxybenzaldimine (TS2) which were characterized by structural, spectroscopic and analytical methods. The ligands TS1 and TS2 were obtained as single crystals from ethanol solution. X-ray diffraction data for two compounds showed that the bond lengths are within the normal ranges. The electrochemical properties of the Schiff base ligands were studied in different solvents and at various scan rates. The luminescence properties of the ligands TS1 and TS2 in different solvents and at different pH values have been investigated. The results show that the ligands exhibit more efficient luminescence properties in CH3CN and n-butanol. 相似文献
245.
P. Achenbach C. Ayerbe Gayoso J. C. Bernauer S. Bianchin R. B?hm O. Borodina D. Bosnar M. B?sz V. Bozkurt P. Byd?ovsky L. Debenjak M. O. Distler A. Esser I. Fri??i? M. Gómez Rodríguez B. G?küzüm K. Grie?inger P. Jennewein E. Kim M. Makek H. Merkel S. Minami U. Müller D. Nakajima L. Nungesser B. ?zel-Tashenov J. Pochodzalla Ch. Rappold T. R. Saito S. Sánchez Majos B. S. Schlimme S. ?irca M. Weinriefer C. J. Yoon 《The European Physical Journal A - Hadrons and Nuclei》2012,48(2):1-8
Cross-section measurements of the exclusive p(e, e??K +)??, ?? 0electroproduction reactions have been performed at the Mainz Microtron MAMI in the A1 spectrometer facility using for the first time the KAOS spectrometer for kaon detection. These processes were studied in a kinematical region not covered by any previous experiment. The nucleon was probed in its third-resonance region with virtual photons of low four-momenta, Q 2 = 0.030?C0.055 (GeV/c)2. The MAMI data indicate a smooth transition in Q2 from photoproduction to electroproduction cross-sections. Comparison with predictions of effective Lagrangian models based on the isobar approach reveal that strong longitudinal couplings of the virtual photon to the N* resonances can be excluded from these models. Modern isobar and Regge-plus-resonance models are in agreement with the data. 相似文献
246.
Semih Korkmaz Evren Oktem Ramin Yazdaanpanah Serap Aksu Mustafa Turkmen 《Molecules (Basel, Switzerland)》2022,27(14)
We present a metamaterial-based perfect absorber (PA) that strongly supports four resonances covering a wide spectral range from 1.8 µm to 10 µm of the electromagnetic spectrum. The designed perfect absorber has metal–dielectric–metal layers where a MgF2 spacer is sandwiched between an optically thick gold film and patterned gold nanoantennas. The spectral tuning of PA is achieved by calibrating the geometrical parameters numerically and experimentally. The manufactured quad-band plasmonic PA absorbs light close to the unity. Moreover, the biosensing capacity of the PA is tested using a 14 kDa S100A9 antibody, which is a clinically relevant biomarker for brain metastatic cancer cells. We utilize a UV-based photochemical immobilization technique for patterning of the antibody monolayer on a gold surface. Our results reveal that the presented PA is eligible for ultrasensitive detection of such small biomarkers in a point-of-care device to potentially personalize radiotherapy for patients with brain metastases. 相似文献