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311.
Elif Avcu Altiparmak Gune Ozen Eroglu Elif Ozcelik Namk
zdemir Serap Erdem Kuruca Nergis Arsu Bahri Ülküseven Tulay Bal‐Demirci 《应用有机金属化学》2019,33(9)
The reaction of salicylaldehyde‐S‐methylisothiosemicarbazone in the presence of ethylenediamine base and iron (III)chloride generated unforeseen homotopic dinuclear triple‐stranded iron (III)helicate. The synthesized helicate was characterized by elemental analysis, IR, UV–Vis spectroscopy, magnetic moment measurement, and evaluated cytotoxic activities against K562, HL‐60 and THP‐1 leukemia cells. In addition, solid‐state structure has been determined by single‐crystal X‐ray diffraction technique. In the complex, three dinucleating O, N, N, O donor ligands provide three diazine (═N─N═) bridges between the metal ions and facial O3N3 coordination spheres around them. The ligands are folded about the N ─ N single bond and coordinated to the two metal ions in a helical fashion to form the triple helical structure. In the crystal lattice, chains of centrosymmetric rings, which are connected to one another via π─π stacking interactions, are generated by C─H···O intermolecular interactions. The results are also confirmed by the density functional theory (DFT) calculations. The results obtained from the cytotoxicity test showed to be effective in low concentrations on the leukemia cells. An intercalative binding mode of helicate‐DNA complex was confirmed with the high intrinsic binding constant (Kb = 8×106 M?1) and competitive displacement assay of Ethidium bromide with high Ksv value. 相似文献
312.
313.
Z.Akdogan M.Demirci O. Sh. Mukhtarov 《数学物理学报(B辑英文版)》2005,25(4):731-740
1IntroductionIt is well-known that the Sturmian Theory is an important aid in solving many problemsin mathematical physics.Therefore this theory is one of the most actual and extensivelydeveloped field in spectral analysis of boundary-value problems of St… 相似文献
314.
Grazing-incidence pumped Ni-like Sn X-ray laser media at 11.9 nm (4d-4p, J = 0-1) is modelled using code EHYBRID and a post-processor code. The required atomic data are obtained using the Cowan code. In this study the pre-formed plasma is pumped on longitudinal direction with a grazing angle. Detailed simulations were performed to optimize the driving laser configurations. Relatively high gain is produced for the Ni-like Sn X-ray laser at 11.9 nm with long pre-pulse and short main pulse drive energy of only 100 mJ on 4 mm slab targets. Using low intensity pre-pulse prior to long pulse decreases the electron density gradient. X-ray resonance lines between 13 and 25 Å emitted from tin plasma have been simulated using post-processor coupled with EHYBRID. The ratio of these resonance lines can be used to measure electron temperature of the laser produced Sn plasma. 相似文献
315.
The widespread use of phosphodiesterase‐5 inhibitors has attracted broad attention of counterfeiters to develop illicit erectile products with inaccurate amounts, unknown toxicity, and purity of active ingredients. Correspondingly, intake of these products endangers consumer health and needs to be screened for precautionary actions to reduce this risk. Therefore, in this study, a sensitive and rapid analytical method has been developed for simultaneous determination of selected phosphodiesterase‐5 inhibitors present in illicit erectile medications and human urine. Quantification of the analytes was performed by liquid chromatography coupled with quadrupole‐time‐of‐flight tandem mass spectrometry system. The chromatographic separation was successfully achieved with a run period of 8 min. Low detection limits were obtained in the range of 1.63–9.81 ng/g with relative standard deviations below 7.72% obtained using the replicate measurements of lowest concentration in calibration plots. The analytical performance of the proposed method proved good linearity, low detection limits, good accuracy and precision with high percent recoveries for human urine samples. Developed method was successfully applied to real samples including four different brands of illicit erectile medications. The results obtained revealed the presence of high levels of sildenafil in analyzed samples. The behaviors of selected phosphodiesterase‐5 inhibitors were also studied in simulated gastric conditions. 相似文献
316.
Füreya Elif Özbek Mustafa Sertçelik Mustafa Yüksek Betül Küçüköz Ertan Şahin 《Journal of Coordination Chemistry》2019,72(5-7):786-795
Two new complexes, [Co(3-fba)2(na)2(H2O)2] (1) and [Ni(3-fba)2(na)2(H2O)2] (2) (where 3-fba = 3-fluorobenzoate and na?=?pyridine-3-carboxamide, nicotinamide), were synthesized and characterized using different techniques (elemental analysis, FT-IR, UV-Vis spectrophotometer, single-crystal X-ray diffraction, fluorescence spectroscopy, and TGA/DTA analysis). X-ray structural analysis revealed that 1 and 2 are isostructural and exhibit distorted octahedral coordination geometry. In each molecule, metal atoms (Co+2 and Ni+2) are linked by two 3-fluorobenzoate anions, two pyridine-3-carboxamide ligands, and two water molecules per formula unit. The 3-fluorobenzoate and pyridine-3-carboxamide are monodentate through a carboxylate oxygen atom and the nitrogen atom of the pyridine ring, respectively. UV-Vis results showed that the studied complexes have absorption edges similar to semiconductor structures. Namely, 1 and 2 indicated emission behaviors around 370?nm and 361?nm, respectively. 相似文献
317.
318.
Yingjie Zhao Kepeng Chen Dr. Elif Akhuseyin Yildiz Shujing Li Yuqi Hou Xue Zhang Dr. Zhijia Wang Prof. Jianzhang Zhao Dr. Antonio Barbon Prof. Halime Gul Yaglioglu Prof. Huijian Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3591-3599
Intersystem crossing (ISC) was observed for naphthalimide (NI)-derived Tröger's base, and the ISC was confirmed to occur by a spin-orbital charge-transfer (SOCT) mechanism. Conventional electron donor/acceptor dyads showing SOCT-ISC have semirigid linkers. In contrast, the linker between the two chromophores in Tröger's base is rigid and torsion is completely inhibited, which is beneficial for efficient SOCT-ISC. Femtosecond transient absorption (TA) spectra demonstrated charge-separation and charge-recombination-induced ISC processes. Nanosecond TA spectroscopy confirmed the ISC, and the triplet state is long-lived (46 μs, room temperature). The ISC quantum yield is dependent on solvent polarity (8–41 %). The triplet state was studied by pulsed-laser-excited time-resolved EPR spectroscopy, and both the NI-localized triplet state and triplet charge-transfer state were observed, which is in good agreement with the spin-density analysis. The Tröger's base was confirmed to be a potent photodynamic therapy reagent with HeLa cells (EC50=5.0 nm ). 相似文献
319.
In this paper we characterize matrices that map every bounded sequence into one whose σ-core is a subset of the
-core of the original sequence. 相似文献
320.
Let T and A be two nonnegative regular summability matrices and W(T,p)∩l∞ and cA(b) denote the spaces of all bounded strongly T-summable sequences with index p>0, and bounded summability domain of A, respectively. In this paper we show, among other things, that is a multiplier from W(T,p)∩l∞ into cA(b) if and only if any subset K of positive integers that has T-density zero implies that K has A-density zero. These results are used to characterize the A-statistical comparisons for both bounded as well as arbitrary sequences. Using the concept of A-statistical Tauberian rate, we also show that is not a multiplier from W(T,p)∩l∞ into cA(b) that leads to a Steinhaus type result. 相似文献