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991.
This study is the development of a new solid phase extraction method based on using magnetic multiwalled carbon nanotubes impregnated with 1-(2-pyridylazo)2-naphthol (PAN) for separation, preconcentration, and flame atomic absorption spectrometric determination of Pb(II) and Cu(II). Optimization of the method was done by investigating pH effect, amount of magnetic multiwalled carbon nanotubes impregnated with PAN, eluent type and volume, matrix effects, and volume of the sample. The optimum adsorbent amount was found to be 75 mg and the optimum pH value was found as 5.5. The detection limits were 16.6 μg L-1 for Pb(II) and 18.9 μg L-1 for Cu(II). The relative standard deviations (RSD%) were less than 4%. Two certified reference materials: SPS-WW2 wastewater and NCS-DC73349 (bush branches and leaves) were used to test the validation of the method. The method was successfully applied to the analysis of Pb(II) and Cu(II) ions in daisy, mint, paprika, sage, rosemary, daphne leaves, heather, green tea, andViburnum opulussamples. 相似文献
992.
In this study, an impedimetric immunosensor based on polymer poly(thiophene)‐graft‐poly(methacrylamide) polymer (P(Thi‐g‐MAm)) modified indium tin oxide (ITO) electrode is developed for the detection of the Neuron Specific Enolase (NSE) cancer biomarker. First, the P(Thi‐g‐MAm) polymer is synthesized and coated on the ITO electrode by using a spin‐coating technique. P(Thi‐g‐MAm) polymer acts as an immobilization platform for immobilization of NSE‐specific monoclonal antibodies. Anti‐NSE antibodies are utilized as biosensing molecules and they bind to the amino groups of P(Thi‐g‐Mam) polymer via glutaraldehyde cross‐linking. Spin‐coating technique is employed for bioelectrode fabrication and this technique provides a thin and uniform film on the ITO electrode surface. This bioelectrode fabrication technique is simple and it generates a suitable platform for large‐scale loadings of anti‐NSE antibodies. This immunosensor exhibits a wide linear detection range from 0.02 to 4 pg mL?1 and with an ultralow detection limit of 6.1 fg mL?1. It reveals a good long‐term stability (after 8 weeks, 78% of its initial activity), an excellent reproducibility (1.29% of relative standard deviation (RSD)), a good repeatability (5.55% of RSD), and a high selectivity. In addition, the developed immunosensor is proposed as a robust diagnostic tool for the clinical detection of NSE and other cancer biomarkers. 相似文献
993.
Isik Aysen Oguz Mehmet Kocak Ahmet Yilmaz Mustafa 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(5-6):439-449
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Cancer is one of the leading causes of death worldwide, and the limited success of currently used anticancer drugs is a driving force for... 相似文献
994.
M. Mustafa Cetin Sara Shafiei-Haghighi Jiazhen Chen Sheng Zhang Amanda C. Miller Daniel K. Unruh Dominick J. Casadonte Jr Tracy L. Lohr Tobin J. Marks Michael F. Mayer J. Fraser Stoddart Michael Findlater 《Journal of polymer science. Part A, Polymer chemistry》2020,58(8):1130-1143
The syntheses of the 2,9-dimesityl-1,10-phenanthroline ( dmesp ) metal complexes, [Cu(dmesp)(MeCN)]PF6 ( 1 ), [Cu(dmesp)2]PF6 ( 2 ), Fe(dmesp)Cl2 ( 3 ), Co(dmesp)Cl2 ( 4 ), Ni(dmesp)Cl2 ( 5 ), Zn(dmesp)Cl2 ( 6 ), Pd(dmesp)MeCl ( 7 ), Cu(dmesp)Cl ( 8 ), and Pd(dmesp)2Cl2 ( 9 ), in good to high yields are described. These complexes were characterized by 1H and 13C NMR spectroscopy, HR–MS (ESI and/or APPI), and elemental analysis (CHN). The solid-state structures of complexes 1 – 8 were determined by single-crystal X-ray analysis and their photophysical properties were also characterized. To demonstrate the versatility of this new platform, complexes 3 – 5 , 8 , and 9 were employed in the catalytic oligomerization of ethylene using modified methyl aluminoxane (MMAO) as the cocatalyst, where Co(II) and Ni(II) complexes ( 4 and 5 , respectively) were found to exhibit moderate selectivity for catalytic dimerization of ethylene to butenes over tri- or tetramerization. Complex 8 is an effective catalyst of both the commonly encountered “click” reaction and amine arylation chemistries. Complexes 6 and 9 were found to be excellent catalysts for Friedel-Crafts alkylation and Suzuki-Miyaura coupling, respectively. 相似文献
995.
996.
Mustafa Yasa Aybuke Deniz Mehrdad Forough Erol Yildirim Ozgul Persil Cetinkol Yasemin Arslan Udum Levent Toppare 《Journal of polymer science. Part A, Polymer chemistry》2020,58(23):3336-3348
Phenolic compounds used in food industries and pesticide industry, are environmentally toxic and pollute the rivers and ground water. For that reason, detection of phenolic compounds such as catechol by using simple, efficient and cost-effective devices have been becoming increasingly popular. In this study, a suitable and a novel matrix was composed using a novel conjugated polymer, namely poly[1-(5-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophen-2-yl)furan-2-yl)-5-(2-ethylhexyl)-3-(furan-2-yl)-4H thieno[3,4-c]pyrrole-4,6(5H)-dione] (PFTBDT) and carbon dots (CDs) to detect catechol. PFTBDT and CDs were synthesized and the optoelectronic properties of PFTBDT were investigated via electrochemical and spectroelectrochemical studies. Laccase enzyme was immobilized onto the constructed film matrix on the graphite electrode. The proposed biosensor was found to have a low detection limit (1.23 μM) and a high sensitivity (737.44 μA/mM.cm−2) with a linear range of 1.25–175 μM. Finally, the applicability of the proposed enzymatic biosensor was evaluated in a tap water sample and a satisfactory recovery (96–104%) was obtained for catechol determination. 相似文献
997.
Mustafa Sertçelik Füreya Elif Özbek Parham Taslimi Murat Durman Mücahit Özdemir Bahattin Yalçın Hacali Necefoğlu Tuncer Hökelek 《应用有机金属化学》2020,34(9):e5802
A novel Ni(II) complex containing 2-fluorobenzoate and 3-hydroxypyridine ligands was synthesized and characterized using elemental analysis, Fourier transform infrared (FT-IR) spectroscopy and single-crystal X-ray diffraction. FT-IR peaks show that the carboxylate group from 2-fluorobenzoate has a monodentate coordination mode. The coordination environment around the Ni2+ ion is of distorted octahedral geometry. The octahedral geometry consists of a total of four oxygen atoms from two carboxylate groups of two fluorobenzoate anions, two water molecules and two nitrogen atoms from two 3-hydroxypyridine ligands. The complex shows excellent inhibitory effects against some metabolic enzymes. Ki values for the complex were found as 108.17 ± 25.63, 124.88 ± 36.20, 28.11 ± 2.87, 20.95 ± 5.65 and 32.63 ± 9.67 μM against human carbonic anhydrase I, human carbonic anhydrase II, α-glycosidase, acetylcholinesterase and butyrylcholinesterase, respectively. In addition, geometry optimization and vibration frequencies were calculated, and single point energy was studied based on optimization. Experimental and theoretical data were compared. The B3LYP/6-31G(d,p) basis set was used for all calculations. 相似文献
998.
999.
Ian Herbert Sanjay Jain Steffen Lempp Manat Mustafa Frank Stephan 《Annals of Pure and Applied Logic》2019,170(12):102716
This paper considers reductions between types of numberings; these reductions preserve the Rogers Semilattice of the numberings reduced and also preserve the number of minimal and positive degrees in their semilattice. It is shown how to use these reductions to simplify some constructions of specific semilattices. Furthermore, it is shown that for the basic types of numberings, one can reduce the left-r.e. numberings to the r.e. numberings and the k-r.e. numberings to the -r.e. numberings; all further reductions are obtained by concatenating these reductions. 相似文献
1000.
The electric counterpart of the magnetic black hole solution found in nonlinear electrodynamics (NED) is presented. The electric field emerges regular and confined whereas the spacetime which satisfies all the energy conditions is singular. Our result is in conformation with a theorem proved before about the existence of regular electric black holes. The thermal properties of the black hole including the first law, Smarr's formula, and the thermal stability are investigated. This provides a chance to compare the electric and magnetic types of black holes in a particular model of NED. 相似文献