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11.
Nesrin Karaali Serdar Aydin Nimet Baltas Emre Mentese 《Journal of heterocyclic chemistry》2020,57(4):1806-1815
A new series of 5,6-dimethyl-2-phenyl-1H-benzimidazole derivatives was synthesized. The antioxidant activities of the synthesized compounds were determined according to the cupric reducing antioxidant capacity (CUPRAC), ABTS, and DPPH assays. Many of the target compounds showed good antioxidant activity. Among these compounds, it has been determined that the carbothioamide and 1,2,4-triazole derivatives had a very good antioxidant capacity. Also, all compounds were screened for in vitro inhibitory activity against Jack bean urease. Among the synthesized molecules, the starting compound, acetate, and acetohydrazide derivatives (with IC50 values 12.02, 11.40, and 8.04 μg/mL, respectively) had a higher inhibitory effect on urease and exhibited a lower IC50 values than acetohydroxamic acid (IC50: 20.50 μg/mL) and thiourea (IC50: 14.04 μg/mL) as a reference inhibitors. 相似文献
12.
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
13.
Aydin Tavman Serkan Ikiz A. Funda Bagcigil N. Yakut Özgür Seyyal Ak 《Russian Journal of Inorganic Chemistry》2010,55(2):215-222
2-Methyl-6-(5-H-methyl-chloro-nitro-1H-benzimidazol-2-yl)-phenols( HL
x
:x= 1-4)ligands and HL1 complexes with Fe(NO3)3, Cu(NO3)2, AgNO3, Zn(NO3)2 have been synthesized and characterized. The structures of the compounds were confirmed on the basis of elemental analysis,
molar conductivity, magnetic moment, FT-IR, 1H-and 13C-NMR. Antibacterial activity of the free ligands, their hydrochloride salts and the complexes were evaluated using the disk
diffusion method in dimethyl sulfoxide as well as the minimum inhibitory concentration dilution method, against nine bacteria.
While HL1 ligand has not any activity, it’s Ag(I) complex show antibacterial effect toward almost to all the bacteria. Zn(II) complex
has antibacterial effect on especially K. pneumoniae, S. epidermidis and S. aureus bacteria. 相似文献
14.
In this study, neutron-emission spectra produced by (n, xn) reactions for some structural fusion materials as 27Al, 51V, 52Cr, 55Mn, and 56Fe have been investigated by a neutron beam up to 16 MeV. Multiple preequilibrium mean-free-path constant from internal transition
and the preequilibrium and equilibrium level-density parameters have been investigated for some (n, xn) neutron-emission spectra calculated in this study. Preequilibrium neutron-emission spectra were calculated by using new-evaluated
hybrid model and geometry-dependent hybrid model, full-exciton model, and cascade-exciton model. The reaction equilibrium
component was calculated by Weisskopf-Ewing model. The obtained results have been discussed and compared with the available
experimental data and found agreement with each other.
The text was submitted by the authors in English. 相似文献
15.
Using Breit-Wigner resonance relation,bounds on the magnetic moment of the tau-neutrino are calculated through the reaction e+e-→v(v)γ at the neutral boson pole in the framework of a superstringinspired E6 model which has one extra low-energy neutral gauge boson and a LRSM. 相似文献
16.
In this correspondence, micro-genetic algorithm (MGA) application results for optimizing the performance of electronic feedback of a laser diode are presented. The goal of optimization is to find the maximum bandwidth of the laser diode with electronic feedback used in fiber optic digital communication. A numerical analysis of the system theory of the single-mode laser diode to obtain numerical results of the gain, the pulse response, and the harmonic distortion for electronic feedback is also presented. The dependence of the system gain on the feedback gain and delay is examined. The pulse response is studied and it is shown that a transmission rate over 1 Gbyte/s can be achieved. 相似文献
17.
Of the chloro-substituted benzoic acids, the 2-chloro and 2,4-dichloro compounds yield higher effective molar absorptivities than benzoic acid does in the Rhodamine B-benzene extractive spectrophotometric procedure for determination of uranium(VI). Carbonyl compounds (especially acetone) in the organic phase enhance the extraction of the ion associate. The stoichiometry of the complexes has been determined, and a method of computing the extraction constants of the ion-associates developed. A spectrophotometric method for determining uranium in the presence of interfering ions has been designed. 相似文献
18.
M.E. Aydin 《Journal of Physics and Chemistry of Solids》2007,68(9):1770-1773
Electrical transport properties of Ag metal-fluorescein sodium salt (FSS) organic layer-silicon junction have been investigated. The current-voltage (I-V) characteristics of the diode show rectifying behavior consistent with a potential barrier formed at the interface. The diode indicates a non-ideal I-V behavior with an ideality factor higher than unity. The ideality factor of the Ag/FSS/p-Si diode decreases with increasing temperature and the barrier height increases with increasing temperature. The barrier height (φb=0.98 eV) obtained from the capacitance-voltage (C-V) curve is higher than barrier height (φb=0.72 eV) derived from the I-V measurements. The barrier height of the Ag/FSS/p-Si Schottky diode at the room temperature is significantly larger than that of the Ag/p-Si Schottky diode. It is evaluated that the FSS organic layer controls electrical charge transport properties of Ag/p-Si diode by excluding effects of the SiO2 residual oxides on the hybrid diode. 相似文献
19.
The synthesis of well-defined block copolymers from styrene and methyl acrylate via ATRP is discussed in this contribution. Kinetic studies on these block copolymerizations as well as characterization studies were performed to investigate the monomer composition in the respective PS and PMA blocks. MALDI-TOF-MS was performed to clarify the exact number of repeating units of each block and the total number of units in the block copolymer. Block copolymers up to 22 kDa could be analyzed by MALDI-TOF-MS, whereby polymers with PMA as first block showed a large second distribution corresponding to PMA homopolymers. However, SEC demonstrated that only a small amount of homopolymer was present indicating that care needs to be taken with interpreting MALDI-TOF-MS data, which is a qualitative rather than a quantitative technique. 相似文献
20.
Isil Aydin Firat Aydin Abdurrahman Saydut E. Gulhan Bakirdere Candan Hamamci 《Microchemical Journal》2010,96(2):247-251
Composition of phosphate rocks mostly depend on their type and origin. Sedimentary rocks contain high concentration of heavy metals. Phosphate rocks are mainly used for the manufacturing of phosphate fertilizers. The contents of heavy metals Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn, as well as rare earth elements Ce, La, and Th were determined in sedimentary phosphate rock used for production of fertilizer in Turkey. The Kasrik-Semikan, Mazidag (Mardin, SE Anatolia, Turkey) high-grade phosphate rock used in this study is situated near the border with Syria and was deposited during the Turonian and Senonian (Cretaceous) ages. Total phosphorus (P) concentration in the rock is 18.5% on the average. Microwave acid digestion (MW-AD) followed by ?nductively Coupled Plasma-Optical Emission Spectrophotometry (ICP-OES) was carried out for the determination of all the elements of interest in phosphate rock. The results revealed that hazardous metal content of the phosphate rock was lower in Mazidag phosphate than that in samples imported from other countries and were within the safety limits. 相似文献