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Unexpected benzimidazole ring formation from a quinoneimide species in the presence of ammonium acetate as supporting electrolyte used in the coupling of electrochemistry with mass spectrometry 下载免费PDF全文
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Triazines are widely used in agriculture around the world as selective pre‐ and post‐emergence herbicides for the control of broad leaf and grassy weeds. With high toxicity and persistence, triazines can contaminate the environment and crops, so the development of rapid and sensitive methods for the determination of different triazines is necessary. Capillary electrophoresis comprises a group of techniques used to separate chemical mixtures. Analytical separation is based on different electrophoretic mobilities. This review focuses on the analysis of triazine herbicides with different modes of capillary electrophoresis, including capillary zone electrophoresis, micellar electrokinetic capillary electrophoresis, capillary electrochromatography and nonaqueous capillary electrophoresis. Determinations of triazines in various matrices such as surface water, groundwater, vegetables, soil and grains are emphasized. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Kacimi Rachid Bourass Mohamed Toupance Thierry Wazzan Nuha Chemek Mourad El Alamy Aziz Bejjit Lahcen Alimi Kamel Bouachrine Mohammed 《Research on Chemical Intermediates》2020,46(6):3247-3262
Research on Chemical Intermediates - A theoretical study on four organic dyes based on bis(4-hexyloxy)triphenylamine as donor and electron acceptor cyanoacrylic acid with a... 相似文献
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Afzal Asif Mohammed Samee A. D. Abdul Razak R. K. Ramis M. K. 《Journal of Thermal Analysis and Calorimetry》2021,144(4):1271-1285
Journal of Thermal Analysis and Calorimetry - The operating temperature of Li-ion batteries used in modern electric vehicles should be maintained within an allowable range to avoid thermal runaway... 相似文献
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Nonlinear Dynamics - Introduction of stiffness nonlinearities to broaden the frequency bandwidth of vibratory energy harvesters has the adverse influence of complicating the response behavior of... 相似文献
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Mohammed Aassila 《Comptes Rendus Mathematique》2002,334(11):961-966
We study the semilinear wave equation utt?Δu=p?k|u|m in , where p is a conformal factor approaching 0 at infinity. We prove that the solutions blow-up in finite time for small powers m, while having an arbitrarily long life-span for large m. Furthermore, we study the finite time blow-up of solutions for the class of quasilinear wave equations utt?Δu=p?k|Lu|m in . To cite this article: M. Aassila, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 961–966. 相似文献
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Let M be a Riemannian m-dimensional manifold with m ≥ 3, endowed with non zero parallel p-form. We prove that there is no minimal isometric immersions of M in a Riemannian manifold N with constant strictly negative sectional curvature. Next we show that, under the conform flatness of the manifold N and some assumptions on the Ricci curvature of N, there is no α-pluriharmonic isometric immersion. 相似文献
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Mohammed Ali Faya Ibrahim 《Czechoslovak Mathematical Journal》2004,54(2):303-313
It was shown in [7] that any right reversible, cancellative ordered semigroup can be embedded into an ordered group and as a consequence, it was shown that a commutative ordered semigroup can be embedded into an ordered group if and only if it is cancellative. In this paper we introduce the concept of L-maher and R-maher semigroups and use a technique similar to that used in [7] to show that any left reversible cancellative ordered L or R-maher semigroup can be embedded into an ordered group. 相似文献