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Enzyme Free Electrochemiluminescence Sensor of Histamine Based on Graphite-carbon Nitride Nanosheets
Fazeleh Mesgari Foad Salehnia Sepideh Mohammad Beigi Morteza Hosseini Mohammad Reza Ganjali 《Electroanalysis》2022,34(4):659-666
The determination of histamine as one of the most important seafood poisoning compounds is essential nowadays. This paper reports a simple novel ECL sensor with g−C3N4 nanosheets (NSs) as an effective signal probe for the measurement of histamine without using any enzymatic reactions or complicated modifications. The ECL response of the sensor was linearly proportional to the concentration of histamine ranging from 1.0×10−7 to 7.5×10−4 mol/L, with a detection limit of 4.30×10−8 mol/L (R2=0.98401). The relative standard deviation (RSD) in repeatability and reproducibility tests were calculated to be 4.7 % and 3.6 % respectively. The presented sensor was successfully applied to the determination of histamine in canned tuna fish samples where it gave recoveries that ranged from 99.72 % to 101.96 % indicating that the method presented here is sensitive with high precision and is expected to have significant potential applications in clinical and the freshness quality of seafood. 相似文献
63.
Shirmehenji Reza Javanshir Sepideh Honarmand Moones 《Journal of Cluster Science》2021,32(5):1311-1323
Journal of Cluster Science - This study deals with producing selenium nanoparticles (SeNPs) by an economical and reliable process using a mining waste that contains significant amounts of selenium... 相似文献
64.
Sepideh Stewart Ralf Schmidt 《International Journal of Mathematical Education in Science & Technology》2017,48(8):S40-S49
ABSTRACTIn this study, we examined a mathematician and one of his students’ teaching journals and thought processes concurrently as the class was moving towards the proof of the Fundamental Theorem of Galois Theory. We employed Tall's framework of three worlds of mathematical thinking as well as Piaget's notion of accommodation to theoretically study the narratives. This paper reveals the pedagogical challenges of proving an elegant theory as the events unfolded. Although the mathematician was conscious of the students’ abilities as he carefully made the path accessible, the disparity between the mind of the mathematician and the student became apparent. 相似文献
65.
Trimellitic anhydride acid chloride (2) was obtained by the reaction of trimellitic anhydride (1) and excess amount of thionyl chloride. The acid chloride was reacted with 4,4′-diaminodiphenyl ether (3), and produced the monomer 4. Anthracene-9-carboxaldehyde (5) was reacted with sulfuryl chloride to produce anthracene-9-carboxylic acid chloride (6) in a quantitative yield. Through the reaction of 6 and 2,4,6-triamino-1,3,5-triazine (7), the monomer 8 was produced in high yield. Two monomers were characterized by 1H NMR and FT-IR spectroscopy, and then were used in the polymerization reaction. A new facile and rapid polycondensation reaction of the two monomers was performed by using a domestic microwave oven. The polymerization reaction proceeded rapidly, compared with the conventional solution polycondensation and was completed within 10 min, producing a photoactive poly(amide-imide) in a quantitative yield. The resulting polymer was characterized by IR, 1H NMR and TGA techniques. Thermogravimetric analysis indicated that polymer 9 was thermally stable in nitrogen atmosphere. In addition the initial decomposition temperature, 5% and 10% weight loss (T5, T10) were 284, 356 and 408 °C. The residual weight percent at 700 °C was 51.5%, which shows it is moderately thermally stable. Fluorescence properties of polymer 9 were investigated in several solvents. The ideal concentration of each case was determined by fluorescence self quenching phenomena. Also the self quenching mechanism was studied according to the specific behavior of the polymer in different solvents. 相似文献
66.
Shadpour E. Mallakpour Abdol‐Reza Hajipour Sepideh Khoee 《Journal of polymer science. Part A, Polymer chemistry》2000,38(7):1154-1160
A new facile and rapid polycondensation reaction of 4,4′‐(hexafluoroisopropylidene)‐N,N′‐bis(phthaloyl‐L‐leucine) diacid chloride (1) with several aromatic diamines, including benzidine (2a), 4,4′‐diaminodiphenyl methane (2b), 1,5‐diaminoanthraquinone (2c), 4,4′‐sulfonyldianiline (2d), 3,3′‐diaminobenzophenone (2e), P‐phenylenediamine (2f), 2,6‐diaminopyridine (2g), 4,4′‐diaminobenzophenone (2h), 2,4‐diaminotoluene (2i), and 4,4′‐diaminodiphenylether (2j), was developed with a domestic microwave oven in the presence of a small amount of a polar organic medium such as o‐cresol. The polymerization reactions proceeded rapidly compared to conventional solution polycondensation and finished within 12 min, producing a series of optically active poly(amide‐imide)s with quantitative yields and high inherent viscosities of 0.50–1.93 dL/g. All of the polymers were fully characterized by IR, elemental analyses, and specific rotation. Some structural characterization and physical properties of these optically active poly(amide‐imide)s are reported. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1154–1160, 2000 相似文献
67.
Seyyed Javad Sabounchei Mohsen Ahmadi Fateme Akhlaghi Bagherjeri Farzaneh Hejazi Keyhaneh Sanaie-Noorani Hamid Reza Khavasi Sepideh Samiee 《Comptes Rendus Chimie》2013,16(11):1017-1023
Reaction of Ph3PCHCOC6H4Me (L), with HgX2 and CdCl2·H2O in methanol with equimolar ratios give binuclear complexes of the type [MX(μ-X){CH(PPh3)C(O)C6H4Me}]2 (M = Hg; X = Cl (1), Br (2), I (3), M = Cd; Cl(4)). The bridge-splitting reaction of binuclear complexes [MX(μ-X){CH(PPh3)C(O)C6H4Me}]2 by dimethyl sulfoxide (DMSO) yields the mononuclear complexes [MX2{CH(PPh3)C(O)C6H4Me}(OSMe2)] (M = Hg; X = Cl (5), Br (6), I (7), M = Cd; Cl (8)). The characterization of these complexes was carried out by elemental analysis and FT-IR, 1H, 31P, and 13C NMR spectroscopies. C-coordination of ylide and O-coordination of DMSO are demonstrated by single-crystal X-ray analysis of mononuclear complex of [HgBr2{CH(PPh3)C(O)C6H4Me}(OSMe2)] (6). Complex 6 is monomeric with tetrahedral geometry around the metal ion. 相似文献
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Yu Jeongjae Wey Michael Firooz Sepideh Khaki Armstrong Daniel W. 《Chromatographia》2021,84(9):821-832
Chromatographia - One of the challenges of hydrophilic interaction liquid chromatography (HILIC) is the development of hydrolytically stable stationary phases. In this work, reproducible synthesis,... 相似文献
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Jee Seong Kwak Nour Bizarri Dr. Sepideh Sharif Wenyao Peter Zhang Dr. Debasis Mallik Prof. Michael G. Organ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15505-15508
Optimization of the asymmetric synthesis of warfarin, an important anticoagulant, has been evaluated using a reconfigurable reaction platform capable of performing batch, continuous flow, and plug-flow synthesis. Further, this platform has been integrated with a novel, multidimensional, multiple variable analysis tool that can evaluate multiple critical quality attributes (CQA), percent conversion and enantiomeric excess in this case, from a single injection that is repeatedly recycled in a closed loop of chromatography columns, a detector and a heart-cut valve. Further, the new, integrated analysis system also facilitates validation of each QA, providing a high-level of confidence in analytical measurements, which are obtained without operator intervention. 相似文献
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Darabi Hossein Reza Nazarian Ramo Alizadeh Sepideh Aghapoor Kioumars Ebadinia Leila 《Journal of fluorescence》2021,31(4):1085-1097
Journal of Fluorescence - Three tweezer?shaped salophenes having catechols (1), phenols (2) and anisoles (3) units in conjunction to the dipodal Schiff bases have been applied for the optical... 相似文献