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991.
Salah Bouhroum Joseph A. Grondin Stephan Houdier Hassan Lazrek Mohamed Rhazi Abdelouahad Tolaimate 《Journal of carbohydrate chemistry》2013,32(3):309-314
ABSTRACT Hydrazine acetate is shown to effect selective deacetylation on peracetylated glycals like D-xylal, D-glucal, D-galactal and L-rhamnal. It is demonstrated that the observed selectivity on the -4 position cannot be explained by acetyl migration during the reaction. 相似文献
992.
A new method, involving the application of PMR spectrometry for the assay of clofibrate and its capsules, is proposed. Among other peaks the PMR spectrum of clofibrate has a well-defined singlet system which is chosen for quantitative measurement. The principle of the method involves comparing the integral of this signal to that of the sharp singlet (positioned at 0.00 ppm) of hexamethylcyclotrisilazane which is used as internal standard. 相似文献
993.
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995.
Mohammed Samar M. Moustafa Ahmed H. El-Sayed Hassan A. Ayman Aya Mohamed Abdussattar S. A. 《Russian Journal of General Chemistry》2022,91(1):S84-S88
Russian Journal of General Chemistry - Functionalization of α-aminopyridine to a new series of pyridine and fused pyridine derivatives has been achieved via its reaction with a variety of... 相似文献
996.
El-Sayed Hassan A. Moustafa Ahmed H. Farargy Ahmed F. El Mohammed Samar M. Saudy Esraa Gad Emad M. 《Russian Journal of General Chemistry》2022,92(4):709-717
Russian Journal of General Chemistry - The present study is devoted to functionalization of ethyl 2-{[3-cyano-6-(4-cyanophenyl)-4-(2,4-dichlorophenyl)pyridin-2-yl]oxy}acetate (1) by triazole-,... 相似文献
997.
Zeinu Mussa Belew Michal Poborsky Hussam Hassan Nour-Eldin Barbara Ann Halkier 《Current Opinion in Green and Sustainable Chemistry》2022
Transport engineering strategies use altered expression of transporter proteins to change metabolite distribution within an organism. The production of plant specialized metabolites in microbial cell factories encounters a set of challenges that could benefit from the implementation of transport engineering technology. The range of challenges includes premature pathway termination due to secretion of intermediates, feedback inhibition due to inefficient export of final products, low yields in bioconversion processes due to inefficient import of precursors, and poor connectivity between subcellular compartments expressing different parts of complex biosynthetic pathways. We highlight the latest examples of transport engineering in microbial cell factories producing plant specialized metabolites, identify the current knowledge gap, and propose future research for advancing the field. 相似文献
998.
Arabali Vahid Karimi-Maleh Hassan Beitollahi Hadi Moradi Reza Ebrahimi Mahmoud Ahmar Hamid 《Ionics》2015,21(4):1153-1161
Ionics - In this study, a carbon paste electrode (CPE) was chemically modified with Pt/carbon nanotubes (CNTs) nanocomposite and 8,9-dihydroxy-7-methyl-12H-benzothiazolo [2,3-b] quinazolin-12-one... 相似文献
999.
Xiao-Jing Liu Chun-Hua Cui Hui-Hui Li Yong Lei Tao-Tao Zhuang Meng Sun Muhammad Nadeem Arshad Hassan A. Albar Tariq R. Sobahi Shu-Hong Yu 《Chemical science》2015,6(5):3038-3043
Hollow alloyed nanoparticles (NPs) represent one kind of promising fuel cell electrocatalyst. However, the formation of single-cavity hollow structures by a dealloying process is quite challenging owing to the random leaching/dissolution of transition metals, surface passivation and the limited diffusion distance of the noble metals. Here we present a facile method to prepare hollow PtPdCu NPs derived from monodisperse alloy NPs by an acetic acid-assisted dealloying process. Here, acetic acid not only acts as a chemical etching agent but also plays an important role in the removal of the residual surfactants for colloidal NPs. Our findings rectify the current knowledge that hollow alloyed NPs cannot be prepared by a dealloying strategy and provide further understanding of the dealloying process in a ternary system. Such unique hollow ternary PtPdCu NPs exhibit outstanding durability and improved catalytic activity toward the oxygen reduction reaction. 相似文献
1000.
In this article, we investigate globally exponentially attractive sets and chaos synchronization for a hyperchaotic system, namely, Lorenz–Stenflo system. For this system, two ellipsoidal globally exponentially attractive sets are derived based on generalized Lyapunov function theory and the extremum principle of function. Furthermore, we propose linear feedback control with a one, two, three, and four inputs to realize globally exponential synchronization of two four‐dimesional hyperchaotic systems using inequality techniques. Numerical simulations are presented to show the effectiveness of the proposed synchronization scheme. © 2014 Wiley Periodicals, Inc. Complexity 20: 30–44, 2015 相似文献