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481.
da Silva Bruno Fonseca da Silva Karolayne Esthefany Melo de Farias Emerson Emiliano Gualberto de França Elvis Joacir Martins Mônica Cristina Barroso de Oliveira Santos Mariana Luiza de Lourdes Lacerda Buril Maria da Silva Alves Gustavo Gabriel de Oliveira Silva Andrezza Karla de Lira Júnior Ednaldo Barbalho da Silva Nicácio Herique Pereira Eugênia C. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3671-3679
Journal of Radioanalytical and Nuclear Chemistry - This study aimed to evaluate the effects of the Rn-222 progeny on the lichen Cladonia verticillaris under controlled conditions. The results... 相似文献
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de Escobar Cícero Coelho Lansarin Marla Azário Santos João Henrique Zimnoch dos Brandestini Milena Duarte 《Journal of Sol-Gel Science and Technology》2018,88(1):220-226
Journal of Sol-Gel Science and Technology - In this work, a ZnO-based molecularly imprinted photocatalyst (MIP) bearing acid Lewis sites (Al) was evaluated for photocatalytic oxidation of glycerol.... 相似文献
486.
Eutectic mixtures as a green alternative for efficient catalyst recycling in atom transfer radical polymerizations 下载免费PDF全文
Pedro Maximiano Patrícia V. Mendonça Madson R. E. Santos João R. C. Costa Tamaz Guliashvili Arménio C. Serra Jorge F. J. Coelho 《Journal of polymer science. Part A, Polymer chemistry》2017,55(3):371-381
A new solvent mixture, based on ethanol/reline (EM: eutectic mixture), was investigated for the supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP) of methyl acrylate (MA) near room temperature, for the first time, affording complete catalyst recovery and reuse. The kinetic results revealed that the polymerizations were controlled, with polymers having narrow molecular weight distributions (? < 1.2). The “living” character of the resultant PMA was confirmed by the synthesis of a well‐defined PMA‐b‐PBA block copolymer. Remarkably, it was demonstrated that the Cu(0)/CuBr2/Me6TREN (Me6TREN: tris[2‐(dimethylamino)ethyl]amine) could be recovered from the final reaction mixture and reused for new successful SARA ATRP of MA, suggesting that the reported system could be very attractive from both the economic and environmental perspectives. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 371–381 相似文献
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Tert‐butyl hydroperoxide‐promoted guanylation of amines with benzoylthioureas: Mechanistic insights by HRMS and 1H NMR 下载免费PDF全文
Henrique Esteves Tiago Oliveira Brito Renato Ribeiro‐Viana Ângelo de Fátima Fernando Macedo Jr. 《Journal of Physical Organic Chemistry》2017,30(12)
Herein, we present a mechanistic study on tert‐butyl hydroperoxide‐promoted guanylation of thioureas by monitoring short lifetime intermediates using electrospray ionisation/time‐of‐flight high resolution mass spectrometry (ESI‐Q‐TOF HRMS). Moreover, 1H nuclear magnetic resonance data allowed us to access kinetic parameters for the main species involved which, allied to the HRMS results, furnished valuable insights over previously reported observations. The results suggested an addition/elimination mechanism involving the aminoiminomethanesulphinic acid, RNC(SO2H)NHR′, and the nucleophilic amine as the main pathway to yield the guanidine. Noteworthy, benzoylthiourea consumption rate presented a nonlinear kinetic behaviour, while tBuOOH and the nucleophilic amine consumptions were found to follow second‐order kinetics. 相似文献
488.
In this Letter, we describe a simple and straightforward method for the synthesis of N-substituted imidazole derivatives. 1,1-carbonyldiimidazole mediates the process, which requires no activation group step. We obtained imidazole derivatives in high yields and with short reaction times. To demonstrate the synthetic significance of the aforementioned compounds, we also describe the synthesis of novel ionic liquids from these derivatives. 相似文献
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Ambient temperature SARA ATRP for meth(acrylates), styrene,and vinyl chloride using sulfolane/1‐butyl‐3‐methylimidazolium hexafluorophosphate‐based mixtures 下载免费PDF全文
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Journal of Theoretical Probability - We describe the excursion point process of the so-called Brox diffusion together with the characteristic measure. We do so in terms of the excursion point... 相似文献