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Data Science and Management 2021年第4期4卷 30-39页

作者： Stephen Zhang ganesh mani Cherry Creek High School Greenwood VillageCO80111USA School of Computer Science Carnegie Mellon UniversityPittsburghPA15213USA

Cryptoassets have experienced dramatic volatility in their prices,especially during the COVID-19 pandemic *** pilot study explores the volatility asymmetry and correlations among three popular cryptoassets(Bitcoin,Ethereum,and Dogecoin)as well as *** Generalized Autoregressive Conditional Heteroskedasticity(GARCH)models are *** find that positive shocks have a greater impact on the volatility of these financial assets than negative shocks of the same magnitude,perhaps a manifestation of the fear of missing out(FOMO)*** research is one of the first to use COVID-19-period volatility of financial assets(in-sample data)to forecast their later COVID-19-period volatility(out-of-sample data).This forecast accuracy is compared to that produced by forecasts using the same out-of-sample data and a longer in-sample *** results indicate that generally,the larger in-sample dataset gives a higher forecast accuracy though the smaller in-sample dataset is from the same regime as the out-of-sample *** also evaluate the correlations among the assets using the Dynamic Conditional Correlation(DCC)framework and find that there is an elevated positive correlation between Gold and Bitcoin during the past two *** Gold-Bitcoin correlation hit its peak during the peak of the COVID-19 pandemic and then fell back to around zero in July 2021 when the pandemic crisis ***,there is a strong positive correlation among the *** correlation among all four assets was stronger during the COVID-19 *** continuing analysis can inform portfolio asset allocation as well as general financial policy decisions.

关键词： Cryptocurrencies Bitcoin Ethereum Dogecoin Gold Correlation Leverage effect EGARCH GJR-GARCH MGARCH DCC

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Microporous Hypercross-linked Conjugated Quinonoid Chromophores of Anthracene: Novel Polymers for CO_2 Adsorption

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Chinese Journal of Polymer Science 2015年第2期33卷 224-235页

作者： Rajangam Vinodh mani ganesh Mei Mei Peng Aziz Abidov Muthiahpillai Palanichamy Wang Seog Cha Hyun-Tae Jang Department of Chemical Engineering Hanseo University Korea Carbon Capture and Sequestration R and D Centre School of Civil and Environmental Engineering Kunsan National University

Microporous hypercross-linked conjugated quinonoid chromophores represent a novel class of amorphous polymers, synthesized by the reaction of anthracene with dimethoxy methane in the presence of FeCl3 catalyst. Their N2 adsorption isotherms confirm their microporous nature. Diffuse reflectance UV-Visible（DRS UV-Vis） spectroscopy confirms their matrix built with the conjugated quinonoids by their broad light absorption characteristics extending from 1000 nm to 200 nm with the absorbance maximum close to 400 nm. The catalyst cross-linked anthracene with ―CH2― bridges and subsequently dehydrogenating them to form quinonoids. Their Fourier transform infrared（FTIR） spectra showed their characteristic quinonoid vibrations between 1600 and 1700 cm-1. The synthesis of polymers was carried out at 30, 40, 50, 60, 70 and 80 ℃, but the quinonoid content of the polymer obtained at 80 ℃ was higher than that of the others. Their scanning electron microscopy（SEM） images showed microspheres of 1 to 5 μm size built with tiny particles. Their surfaces were not smooth. The polymer synthesized at 80 ℃ showed 5.1 wt% CO2 sorption at 25 ℃ and 0.1 MPa, but when it was recross-linked, the CO2 sorption increased to 8 wt%. Hence, hypercross-linked conjugated quinonoid chromophores of anthracene are good for sorption of CO2.

关键词： Anthracene Hypercross-linked polymers CO2 adsorption Friedel-Crafts reaction Quinonoid chromophores

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ZSM-5沸石结晶度对乙苯叔丁基化对位选择性的影响(英文)

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催化学报 2013年第2期34卷 294-304页

作者： PUSHPARAJ Hemalatha mani ganesh MUTHIAHPILLAI Palanichamy VELAYUTHAM Murugesan PARK Yong-Ki CHOI Won Choon JANG Hyun Tae Department of Chemical Engineering Hanseo University Seosan-si 356 706 South Korea Department of Chemistry Anna University Chennai 600 025 India Green Chemistry Research Division Korea Research Institute of Chemical Technology Jang-dong 100. Daejeon 305 600 South Korea

Highly crystalline ZSM-5 zeolites are important for para-selective alkylation of alkyl aromatics, because they carry few external acid sites for isomerization of p-dialkyl products. Such zeolites (Si/Al = 25, 50, and 75) were synthesized in a fluoride medium between pH 4 and 6. Their crystallinities, crystal sizes, and surface areas were higher than those of a commercial ZSM-5 zeolite. Their para selectivities in alkylation were tested for vapor-phase tert-butylation of ethylbenzene between 200 and 400 °C. As expected, all the catalysts showed more than 90% para selectivity. At 300 °C, ethylbenzene conversion decreased in the order ZSM-5(25, commercial) > ZSM-5(25) > ZSM-5(50) > ZSM-5(75). The catalysts had weak, medium, and strong acid sites, but all the acid sites of ZSM-5(75) were weaker than those of ZSM-5(25) and ZSM-5(50). The high activity of commercial ZSM-5 was caused by its strong acid sites being stronger than those of the synthesized zeolites. Although the activity of the commercial catalyst was higher than those of the present catalysts, the selectivity for 4-t-butylethylbenzene (4-t-BEB) was low. The optimum feed ratio (ethylbenzene:t-butyl alcohol) was 2:1 and the feed rate was 1.65 h?1 for high ethylbenzene conversion and 4-t-BEB selectivity. Time-on-stream studies showed slow catalyst deactivation. Highly crystalline ZSM-5 zeolites are therefore better than a commercial zeolite for para-selective alkylation of alkyl aromatics. They do not require much post-modification for high para selectivity. A fluoride medium is therefore better than an alkaline medium for obtaining highly crystalline para-selective ZSM-5 zeolites.

关键词： ZSM-5 Fluoride medium P-selectivity Ethylbenzene Tert-butylation Zeolite

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Learning from Japan for Possible Improvement in Existing Disaster Risk Management System of Nepal

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Open Journal of Earthquake Research 2019年第2期8卷 85-100页

作者： ganesh Kumar Jimee Kimiro Meguro Amod mani Dixit Institute of Industrial Science The University of Tokyo Tokyo Japan National Society for Earthquake Technology-Nepal (NSET) Lalitpur Nepal International Center for Urban Safety Engineering Institute of Industrial Science The University of Tokyo Tokyo Japan Asian Disaster Risk Reduction Network (ADRRN) Kathmandu Nepal

Nepal and Japan, both are multi-hazard prone countries having experience of devastating disasters. It is difficult, if not impossible, to stop natural hazard events at source. However, the impact can be reduced significantly by preventing them from turning into disasters. The impact of disasters can vary depending on the capacity to handle the situation;and the capacity depends on the level of preparedness and mitigation measures taken in advance. Japan has set example for the rest of the world when it comes to Disaster Risk Management (DRM). Recovery and reconstruction after disasters are not just to develop the area as it was earlier, but it has to be taken as an opportunity for developing better than earlier, which is called as “Build Back Better”. This concept was raised by Japanese Government in UN World conference, Sendai in 2015 [1]. Dynamic, evolutionary and proactive DRM policy and plans with innovation, and the use of science and technology to find solutions, and effective implementation of the policy and plans, coupled with the culture of safety among the citizens, and the spirit of never give up “Nana KarobiYa Oki” (Seven times fall down, Eight times get up), are the unique features that every country should learn from Japan’s DRM mechanism. This paper is an effort to buy-in the good practices from Japan to improve DRM system in Nepal. It is a product of three-month intensive research in the University of Tokyo under a PhD research that consisted of reviewing existing DRM documents and several interactive meetings with stakeholders in Japan.

关键词： Learnings from Japan Disaster Risk Management Act Disaster

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