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991.
An improved hybrid method is introduced in this paper as a numerical method to reconstruct the scatterer by far-field pattern for just one incident direction with unknown physical properties of the scatterer. The improved hybrid method inherits the idea of the hybrid method by Kress and Serranho which is a combination of Newton and decomposition method, and it improves the hybrid method by introducing a general boundary condition. The numerical experiments show the feasibility of this method. 相似文献
992.
The synthesis of 3-benzylflavone derivatives was efficiently performed in a one-pot method using substituted 2-hydroxy-acetophenone and appropriate benzaldehydes in the presence of pyrrolidine and ethanol. The distinct features of this methodology include simple procedure, easy purification, and good yields. 相似文献
993.
An efficient one-pot procedure for the synthesis of 2-ethoxycarbonyl indoles from commercially available materials has been developed. The one-step procedure involves in situ formation of the hydrazones from phenylhydrazine hydrochloride and ethyl pyruvate in the presence of bismuth nitrate followed by Fischer cyclization in polyphosphoric acid and ethanol. This method is efficient and simple. 相似文献
994.
Here we report a novel Baker yeast catalyzed one pot cyclocondensation, performed at room temperature in ethanol for obtaining high yields of polyfunctionalized pyridines, 2-amino-4-aryl-3,5-dicyano-6-phenylthiopyridines. The developed protocol obeys certain green principles and is scalable and cost effective. 相似文献
995.
A. I. Zadorin 《Computational Mathematics and Mathematical Physics》2008,48(9):1634-1645
Linear and quadratic spline interpolation methods for a one-variable function with a boundary-layer component are examined. It is shown that the interpolation method for such a function leads to considerable errors when applied on a uniform mesh. The error of linear and quadratic spline interpolations on meshes that are refined in the boundary layer is estimated. Numerical results are presented. 相似文献
996.
997.
Eckhard Weissflog 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):489-490
Abstract Die Reaktion von 1.2-Ethandithiol mit 1.3-Dibromopropan oder 1.2-Dibromethan mit 1.3-Propandithiol, in hoher Verdünnung, führt in guten Ausbeuten zur Bildung von 1.4-Dithiepan, dessen Eigenschaften hier beschrieben werden. The reactions of 1,2-ethane dithiole with 1,3-dibromo propane or 1,2-dibromo ethane with 1,3-propane dithiole, carried out in high dilution, lead to the formation of 1,4-dithiepane in good yields. All available properties of this compound are described. 相似文献
998.
Back Cover: One‐Pot Template‐Free Synthesis of NaYF4 Upconversion Hollow Nanospheres for Bioimaging and Drug Delivery (Chem. Asian J. 6/2014)
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999.
Sang Jin Shin Young Chang Yu Ja Deok Seo Sung Ju Cho Ji Ho Youk 《Journal of polymer science. Part A, Polymer chemistry》2014,52(11):1607-1613
Amphiphilic, biocompatible poly(N‐vinylpyrrolidone)‐b‐poly(l ‐lactide) (PVP‐b‐PLLA) block polymers were synthesized at 60 °C using a hydroxyl‐functionalized N,N‐diphenyldithiocarbamate reversible addition–fragmentation chain transfer (RAFT) agent, 2‐hydroxyethyl 2‐(N,N‐diphenylcarbamothioylthio)propanoate (HDPCP), as a dual initiator for RAFT polymerization and ring‐opening polymerization (ROP) in a one‐step procedure. 4‐Dimethylamino pyridine was used as the ROP catalyst for l ‐lactide. The two polymerization reactions proceeded in a controlled manner, but their polymerization rates were affected by the other polymerization process. This one‐step procedure is believed to be the most convenient method for synthesizing PVP‐b‐PLLA block copolymers. HDPCP can also be used for the one‐step synthesis of poly(N‐vinylcarbazole)‐b‐PLLA block copolymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1607–1613 相似文献
1000.