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1.
J Org Chem ; 88(13): 9187-9198, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37291966

RESUMO

Direct access to substituted dihydrochalcones from the easily available starting materials 3-hydroxypropionitrile derivatives and arylboronic acids is described. The procedure involves a multicomponent aryl addition/hydroxyl elimination/reduction Heck approach in the presence of a Pd catalyst with excellent functional group tolerance and a wide range of substrates. In addition, mixed 1,3-diarylation of 3-hydroxypropanenitrile using two arylboronic acids with different electronic properties was also achieved.


Assuntos
Ácidos Borônicos , Paládio , Paládio/química , Estrutura Molecular , Ácidos Borônicos/química , Catálise
2.
J Sports Sci ; 36(23): 2675-2683, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28880783

RESUMO

Competitive balance is important because it enhances outcome uncertainty and therefore it promotes spectator interest, and encourages government investment in a sport. This article analyses the distribution of gold medals, medals, medal points and top eight points amongst nations in table tennis from 1988 to 2016 at the Olympic Games and the World Championships respectively. A normalised version of the Herfindahl-Hirschman Index and a coefficient of variation are calculated for each nation's share of these performance indicators. The key findings are that China dominates both events, with successful female players being more dominant than their male counterparts. The competitive balance for gold medals has declined, whilst there is a trend towards improved competitive balance for top eight points for women, suggesting that more teams are featuring in the top eight (but not necessarily the top three) placings. This research has implications for the development of table tennis competitions. Compared to other racket sports, the issue of competitive imbalance in table tennis is particularly thorny, which threatens the long-term development of this sport. Accordingly, some measures are recommended for the International Olympic Committee and the International Table Tennis Federation to propel a more balanced development of international table tennis.


Assuntos
Logro , Desempenho Atlético , Tênis , Atletas , China , Comportamento Competitivo , Feminino , Humanos , Masculino
3.
Org Lett ; 23(20): 7955-7960, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34585572

RESUMO

A new method for converting easy availability starting materials 2-(2-oxoindolin-3-yl)acetonitrile, arylboronic acids, and alcohols into 2-arylquinoline-4-carboxylates is reported. The procedure involves a three-component addition/ring expansion/esterification reaction in the presence of Pd(II) catalyst with high functional group tolerance under mild conditions. In addition, the photophysical properties of the resulting product were investigated and exhibited excellent polarity-sensitive fluorescence properties and AIE property.

4.
Environ Sci Pollut Res Int ; 27(11): 11484-11493, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32077032

RESUMO

This paper aims to give a condensed introduction to the general mechanisms for policy-making on environmental remediation at the post-closure US contaminated nuclear sites, the accomplishment of "Clean Closure," and the process of setting the goal "Closure in Place." The researches were conducted in three perspectives including overall guidelines, principles of corrective actions, and implementation of practical measures. The results indicated that the round of environmental restoration policies at the post-closure US contaminated nuclear test sites were comprehensive. It was supported by the visions and principles of differentiated and classified governance, demand-driven approach, highlights, unified planning, and progressive implementation in all directions. Meanwhile, it elaborates the diverse policy-making related issues of environmental governance at the polluted US nuclear sites upon closure and presents the preliminary analysis on them respectively to demonstrate valuable reference for the similar researches on the environmental governance of the contaminated nuclear areas as expected.


Assuntos
Recuperação e Remediação Ambiental , Conservação dos Recursos Naturais , Política Ambiental , Formulação de Políticas , Estados Unidos
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