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71.
《Journal of separation science》2017,40(16):3327-3334
We report the synthesis, characterization, and application of [Zn(1,4‐benzenedicarboxylate)(H2O)2]n , Zn(1,4‐benzenedicarboxylate)0.99(NH2‐1,4‐benzenedicarboxylate)0.01(H2O)2]n , [Zn(1,4‐benzenedicarboxylate)0.95(NH2‐1,4‐benzenedicarboxylate)0.05(H2O)2]n , and [Zn(1,4‐benzenedicarboxylate)0.9(NH2‐1,4‐benzenedicarboxylate)0.1(H2O)2]n as sorbents for the extraction of multiclass pesticides from coconut palm. Liquid chromatography with ultraviolet diode array detection was used as the analysis technique, and the experiments were performed at one fortification level (0.1 μg/g). The recoveries were 47–67, 51–70, 58–72, and 64–76% for [Zn(1,4‐benzenedicarboxylate)(H2O)2]n , Zn(1,4‐benzenedicarboxylate)0.99(NH2‐1,4‐benzenedicarboxylate)0.01(H2O)2]n , [Zn(1,4‐benzenedicarboxylate)0.95(NH2‐1,4‐benzenedicarboxylate)0.05(H2O)2]n , and [Zn(1,4‐benzenelate)0.95(NH2‐1,4‐benzenedicarboxylate)0.05(H2O)2]n , and [Zn(1,4‐benzenedicarboxylate)0.9(NH2‐1,4‐benzenedicarboxylate)0.1(H2O)2]n , respectively, with relative standard deviation ranging from 1 to 7% (n = 3). Detection and quantification limits were 0.01–0.05 and 0.05–0.2 μg/g, respectively, for the different pesticides studied. The method developed was linear over the range tested (0.01–10.0 μg/g) with r 2 > 0.9991. A direct comparison of [Zn(1,4‐benzenedicarboxylate)0.9(NH2‐1,4‐benzenedicarboxylate)0.1(H2O)2]n with the commercially available neutral alumina showed that [Zn(1,4‐benzenedicarboxylate)0.9(NH2‐1,4‐benzenedicarboxylate)0.1(H2O)2]n was a similar extracting phase for the pesticides investigated. 相似文献
72.
In this paper, an efficient method for solving nonlinear Stratonovich Volterra integral equations is proposed. By using Bernoulli polynomials and their stochastic operational matrix of integration, these equations can be reduced to the system of nonlinear algebraic equations with unknown Bernoulli coefficient which can be solved by numerical methods such as Newton’s method. Also, an error analysis is valid under fairly restrictive conditions. Furthermore, in order to show the accuracy and reliability of the proposed method, the new approach is compared with the block pulse functions method by some examples. The obtained results reveal that the proposed method is more accurate and efficient than the block pulse functions method. 相似文献
73.
The aim of this paper is to present an efficient analytical and numerical procedure for solving systems of nonlinear Fredholm–Volterra integral equations of the Hammerstein type with the aid of fixed point techniques and the usual Schauder basis in an adequate Banach space. 相似文献
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Ratikanta Behera 《Linear and Multilinear Algebra》2017,65(8):1662-1682
The notion of the Moore–Penrose inverse of tensors with the Einstein product was introduced, very recently. In this paper, we further elaborate on this theory by producing a few characterizations of different generalized inverses of tensors. A new method to compute the Moore–Penrose inverse of tensors is proposed. Reverse order laws for several generalized inverses of tensors are also presented. In addition to these, we discuss general solutions of multilinear systems of tensors using such theory. 相似文献
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