Contents of three forms of water in coal: free water, bound water, and nonfreezable water were measured with a coal prepared at different humid conditions (23–25°C, 53, 75, 97% relative humidity (RH), as received basis) by using differential scanning calorimetry. The obtained data showed that coal prepared at 97%RH or below contained one or two forms of water: only nonfreezable water or nonfreezable water and bound water. Contents of two forms of water, oxygen-containing functional groups (phenolic hydroxyl and carboxyl groups), specific surface area and pore volume of coals were measured with five coals, and the relationships between the contents of two forms of water and the coal structures were evaluated. It was clarified that the contents of nonfreezable water had good correlations with total contents of the phenolic hydroxyl and carboxyl groups, and the contents of bound water prepared at 97%RH was more correlated with pore volume than specific surface area.

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a single-stranded RNA virus which causes COVID-19 (coronavirus disease 2019). SARS-CoV-2 invade a human airway epithelium cell through binding of its Spike (S)-protein to ACE2 (angiotensin converting enzyme 2). Approved anti-inflammatory drugs and a viral RNA-dependent RNA polymerase (RdRp) inhibitor underdevelopment for other disease were repositioned for the COVID-19 treatment. Furthermore, neutralization antibodies targeting the S-protein and antiviral drugs of RdRp or 3CL protease inhibitors were newly developed within only 3 years. The innovations of the drug discovery and development, including regulation, realized the rapid release of drugs to the market.

In the face of the novel coronavirus infection (COVID-19), researchers and medical professionals worldwide have been tackling to develop new drug products, and regulatory authorities also have accelerated their efforts to create new schemes for the fast-track approval of drug products. This article outlines the approval systems including the newly established emergency approval system and describes the trends in the development of COVID-19 drug products and vaccines in Japan.

We have fought from various fields as well as the medical field against COVID-19 for three years. Virus droplet simulations have been carried out from the fluid engineering field. First, the simulations were conducted using PC. Then, we have used the supercomputer Fugaku for the simulations. In the computation, dispersion of novel coronavirus-laden droplets were estimated. The results suggests that the efficacy of the social distancing and the necessity of wearing a face mask. Furthermore, the simulation of prolonged airborne dispersions of the droplets showed the importance of the air ventilation. Now we are developing accurate dynamic simulation and also constructing the simple risk evaluation system using smartphone against not only COVID-19 but also the upcoming novel viruses.

It was successful to obtain water containing reactive oxygen species with high-concentration by developing novel electrode for the electrolysis of water. The concentration of reactive oxygen species is more than 5 ppm in terms of ozone mass. This concentration is quite high comparing with that of ozone water having obtained by usual methods such as bubbling. We conducted researches to examine the effect of the water on the sanitization of fungus and inactivation of several infective viruses. Then it was clarified that the water with high-concentration reactive oxygen species showed excellent inactivation for at least tested SARS-CoV-2 and Influenza A virus. However the effectiveness of concentration of 2.5 ppm was restricted to show about 90% of Influenza A virus was inactivated. The lower concentration could inactivate less virus and the concentration of 0.5 ppm was not statistically significant comparing with tap water. We successfully developed the atomizer to spray water containing reactive oxygen species. We also conducted researches to clarify the effectiveness of mist spray to space on the sanitization of fungus and inactivation of several infective viruses. Consequently it was revealed that spray of mist containing reactive oxygen species to space is also effective more or less.