Hot isostatic pressing of silicon nitride Sisub3n4 containing zircon, or zirconia and silica

A hydrothermal synthesis apparatus with a 10 KB cylinder was used to obtain a sintered body of silicon nitride. The sintering auxiliary agents used were zircon (ZrSiO4) and a mixture of zirconia (ZrO2) and silica (SiO2). Experiments were conducted with the amounts of ZrSi04 or ArO2 and SiO2 varying over a wide range and the results compared to discover the quantity of additive which produced sintering in silicon nitride by the hot pressing method

Disaster report of 2018 July heavy rain for geo-structures and slopes in Okayama

In July 2018, heavy rain and a large amount of damage to geo-structures and natural slopes were reported in Okayama, Japan. In particular, in the area surrounding the Oda River System, 52 people drowned due to the breach of river banks. Besides the flooding of rivers, the earth-fill dams of many water reservoirs were damaged. The stability of the large number of earth-fill dams in the Setouchi area is very important. Heavy rain is often associated with the collapse of slopes. In Okayama, many shallow slope failures or debris flows occurred over a wide area, particularly in the western part of the prefecture. Through detailed investigations, the mechanism of this geo-disaster was clarified