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51.
Direct Electrochemical Sensing of Phenazine‐1‐carboxylic Acid Secreted by Pseudomonas chlororaphis subsp. aureofaciens BCRC 11057T Using Disposable Screen‐printed Carbon Electrode 下载免费PDF全文
Asif Hameed Hong‐Wei Pi Shih‐Yao Lin Wei‐An Lai Li‐Sen Young You‐Cheng Liu Fo‐Ting Shen Chiu‐Chung Young 《Electroanalysis》2016,28(4):846-853
A novel electrochemical approach for direct recognition of antibiotic phenazine‐1‐carboxylic acid (PCA) was developed. PCA was electropolymerized on preanodized screen‐printed carbon electrode (SPCE*‐PCA) through repetitive cyclic voltammetry and characterized by XPS and FESEM. Electron transfer involved intermediate phenomenon of diffusion‐controlled redox process and surface bound redox reaction. At pH 8 (optimum), SPCE*‐PCA had a detection limit of 0.51±0.04 μM, a quantification limit of 1.7±0.13 μM, linearity of up to 50 µM, a repeatability of 15.5 % and a reproducibility of 1.7 %. PCA secreted by Pseudomonas chlororaphis subsp. aureofaciens BCRC 11057T was investigated successfully using present single run approach. 相似文献
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We consider the conditions under which the Cayley transform of the Kronecker product of two Hermitian matrices can be again presented as a Kronecker product of two matrices and, if so, if it is a product of the Cayley transforms of the two Hermitian matrices. We also study the related question: given two matrices, which matrix under the Cayley transform yields the Kronecker product of their Cayley transforms. 相似文献
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In this paper we investigate identities with two generalized derivations in prime rings. We prove, for example, the following result. Let R be a prime ring of characteristic different from two and let F 1, F 2 : R → R be generalized derivations satisfying the relation F 1(x)F 2(x) + F 2(x)F 1(x) = 0 for all ${x \in R}$ . In this case either F 1 = 0 or F 2 = 0. 相似文献
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Ajda Fo?ner 《Aequationes Mathematicae》2012,84(1-2):91-98
We study the generalized Hyers–Ulam stability of functional equations of module left (m, n)-derivations. 相似文献
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A H2O2-HBr system and N-bromosuccinimide in an aqueous medium were used as a ‘green’ approach to electrophilic and radical bromination. Several activated and less activated aromatic molecules, phenylsubstituted ketones and styrene were efficiently brominated ‘on water’ using both systems at ambient temperature and without an added metal or acid catalyst, whereas various non-activated toluenes were functionalized at the benzyl position in the presence of visible light as a radical activator. A comparison of reactivity and selectivity of both brominating systems reveals the H2O2-HBr system to be more reactive than NBS for benzyl bromination and for the bromination of ketones, while for electrophilic aromatic substitution of methoxy-substituted tetralone it was higher for NBS. Also, higher yields of brominated aromatics were observed when using H2O2-HBr ‘on water’. Bromination of styrene reveals that not just the structure of the brominating reagent but the reaction conditions: amount of water, organic solvent, stirring rate and interface structure, play a key role in defining the outcome of bromination (dibromination vs bromohydroxylation). In addition, mild reaction conditions, a straightforward isolation procedure, inexpensive reagents and a lower environment impact make aqueous brominating methods a possible alternative to other reported brominating protocols. 相似文献
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G. A. Van Fo Fy 《Mechanics of Composite Materials》1968,4(4-6):913-916
On the basis of previously proposed models of reinforced media with regular structure, a method is developed for determining the electromagnetic fieldand dielectric and magnetic constants of reinforced polymers treated as ideal dielectrics. The solution obtained describes the static electromagnetic field and is suitable for investigating the propagation in reinforced media of electromagnetic waves whose length exceeds the distance between adjacent fibers. The dependence of the macroscopic constants on the orientation and volume content of the reinforcement is investigated.Institute of Mechanics, AS UkrSSR, Kiev. Translated from Mekhanika Polimerov, Vol. 4, No. 6, pp. 1130–1133, November–December, 1968. 相似文献