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1.
Quantitative determination of omega-6 and omega-3 polyunsaturated fatty acids in human plasma and urine with high accuracy and precision provides significant information to monitor the underlying etiology of several diseases. In this regard, liquid chromatography-mass spectrometry is a good choice owing to its great selectivity and sensitivity. Additionally, the hybrid quadrupole–time of flight–mass spectrometer systems provides easy identification of target compounds with superior mass measurements. In this study, an analytical method has been developed for simple, accurate and simultaneous determination of linoleic acid, arachidonic acid, docosahexaenoic acid and eicosapentaenoic acid in a short chromatographic analysis period. The developed method is suitable for the quantitative detection of these four compounds with detection limits ranging between 1.1–3.0 ng ml−1 and its applicability was assessed in human urine and plasma samples. As a result, acceptable accuracy (between 83 and 111%) and good precision (<6%) were obtained for target compounds using matrix matching calibration strategy. 相似文献
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Letters in Mathematical Physics - This article is devoted to discovering Lie symmetry algebra of a (3 + 1)-dimensional Davey–Stewartson system which appears in the field of plasma physics. It... 相似文献
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Ukrainian Mathematical Journal - The method of Green’s functional is a little-known technique for the construction of fundamental solutions to linear ordinary differential equations (ODE)... 相似文献
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zcan Bekta 《Mathematical Methods in the Applied Sciences》2019,42(16):5215-5232
The split and hyperbolic (countercomplex) octonions are eight‐dimensional nonassociative algebras over the real numbers, which are in the form , where em's have different properties for them. The main purpose of this paper is to define the split‐type octonion and its matrix whose inputs are split‐type octonions and give some properties for them by using the real quaternions, split, and hyperbolic (countercomplex) octonions. On the other hand, to make some definitions, we present some operations on the split‐type octonions. Also, we show that every split‐type octonions can be represented by 2 × 2 real quaternion matrix and 4 × 4 complex number matrix. The information about the determinants of these matrix representations is also given. Besides, the main features of split‐type octonion matrix concept are given by using properties of real quaternion matrices. Then, 8n × 8nreal matrix representations of split‐type octonion matrices are shown, and some algebraic structures are examined. Additionally, we introduce real quaternion adjoint matrices of split‐type octonion matrices. Moreover, necessary and sufficient conditions and definitions are given for split‐type octonion matrices to be special split‐type octonion matrices. We describe some special split‐type octonion matrices. Finally, oct‐determinant of split‐type octonion matrices is defined. Definitive and understandable examples of all definitions, theorems, and conclusions were given for a better understanding of all these concepts. 相似文献
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Annals of Operations Research - Construction heuristics play an important role in solving combinatorial optimization problems. These heuristics are usually used to create an initial solution to the... 相似文献
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Ukrainian Mathematical Journal - We determine some classes of left modules satisfying the radical formula in a noncommutative ring. We also show that, under a certain condition, a finitely... 相似文献
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Öztürk Müjdat Çalişir Oğuzhan Genç Gamze 《Journal of Thermal Analysis and Calorimetry》2021,145(3):1431-1443
Journal of Thermal Analysis and Calorimetry - In this study, the energy, exergy and economic (3E) analyses were performed for the photovoltaic/thermal collector-assisted heat pump domestic water... 相似文献