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Degradation of nitrilotriacetic acid (NTA) by oxidation with lead dioxide suspension has been studied by differential pulse polarography. The NTA was degraded over the pH range from 4 to 9, with formation of glycine or a mixture of iminodiacetic acid and glycine. After shaking with lead dioxide for 1 hr at 30 degrees and pH ~7, the NTA was almost completely decomposed, the molar reacting ratio of Pb(IV) to NTA being ~17:1; down to 1 x 10(-5)M NTA was decomposed in a shaking time as short as 15 min and at a temperature as low as 5 degrees . The iron(III)-NTA complex was also degraded under the same conditions, and the iron released was adsorbed on the lead dioxide. 相似文献
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A stereoselectivity in an intramolecular cycloaddition of the olefinic -quinodimethanes 13 and 23 generated from the thermolysis of optically active 4β-[2-(4-methoxybenzocyclobutenyl)ethyl] -5α-methoxymethyl-3-phenyl-thio-methylenefuran-2-ones 12 and 22, respectively, is studied and a stereoselective synthesis of (+)--4,5-( 4-methoxybenzo) -1β,7aβ-(2α-methoxymethyl-5-oxofuro)hydrindane 1 is also described. 相似文献
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In the presence of BF3·.OEt2, aryl dienyl ethers were rearranged under mild conditions to afford dienyl phenols in good yields. 相似文献
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Md Asadul Hoque Hideaki Komiyama Hiroki Nishiyama Keiji Nagai Takehiro Kawauchi Tomokazu Iyoda 《Journal of polymer science. Part A, Polymer chemistry》2016,54(9):1175-1188
Well‐defined A3B‐, A2B2‐, and AB3‐type 4‐miktoarm star copolymers (Mn = 10,500–16,200, Mw/Mn = 1.16–1.18) consisting of poly(ethylene oxide) (PEO) and polymethacrylate bearing an azobenzene mesogen (PMA(Az)) as the arms and cyclotetrasiloxane as the core unit were synthesized using a combined route composed of a thiol‐ene click reaction and atom transfer radical polymerization. Microphase‐separated structures of the star copolymers in thin films with a thickness of approximately 100 nm were investigated by GISAXS and TEM. The A3B‐type star‐(PEO)3[PMA(Az)]1 copolymer formed a more highly ordered PEO cylinder array with perpendicular alignment in the PMA(Az) matrix than that of the corresponding linear‐type block copolymer. The center‐to‐center distance of the PEO cylinders and the cylinder diameter were 13 and 4 nm, respectively. The highly ordered star‐(PEO)3[PMA(Az)]1 thin film was directly transferred to a siloxane‐based nanodot array by oxygen reactive ion etching. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1175–1188 相似文献
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