RESUMO
The COVID-19 pandemic has a significant impact on the global economy and health. While the pandemic continues to cause casualties in millions, many countries have gone under lockdown. During this period, people have to stay within walls and become more addicted towards social networks. They express their emotions and sympathy via these online platforms. Thus, popular social media (Twitter and Facebook) have become rich sources of information for Opinion Mining and Sentiment Analysis on COVID-19-related issues. We have used Aspect Based Sentiment Analysis to anticipate the polarity of public opinion underlying different aspects from Twitter during lockdown and stepwise unlock phases. The goal of this study is to find the feelings of Indians about the lockdown initiative taken by the Government of India to stop the spread of Coronavirus. India-specific COVID-19 tweets have been annotated, for analysing the sentiment of common public. To classify the Twitter data set a deep learning model has been proposed which has achieved accuracies of 82.35% for Lockdown and 83.33% for Unlock data set. The suggested method outperforms many of the contemporary approaches (long short-term memory, Bi-directional long short-term memory, Gated Recurrent Unit etc.). This study highlights the public sentiment on lockdown and stepwise unlocks, imposed by the Indian Government on various aspects during the Corona outburst.
RESUMO
A highly selective and sensitive novel Isophthalohydrazide-cDB24C8 cryptand derivative was developed for fluoride recognition at a very low concentration of 2.31â¯×â¯10-10â¯M. The binding was established by UV-Vis, fluorescence and 1H NMR titration. The receptor formed very strong H-bonded complex with fluoride, furnished a sharp new UV-Vis absorption peak at 280â¯nm which was also supported by the DFT-study. The fluorescence emission spectra showed large quenching up to 79.13% upon addition of fluoride.
