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Impact rockburst is induced by the combined static and dynamic loads after excavation.There are two types of impact rockburst experiments，one is induced by changing the static load and another is induced by changing the amplitude of dynamic load.The sandstone fragments after these two experiments were collected.Meanwhile，the sandstone fragments generated from the similar compression experiment under static load were collected too.And the mass， length，width and thickness of each fragment has been measured respectively.The quantities and mass distribution of fragments with coarse，medium，fine and micro grains in different size ranges，and size distribution were further analyzed.The crushing level and shape characteristic of fragments were obtained.Then the fractal dimensions were calculated.The results show that the degree of crushing level of fragments from impact rockburst is higher and with obvious slice shape；the ways of combined static and dynamic loads have a little effect on the crushing level and scale characteristic of fragments from impact rockburst experiments；energy dissipation from impact rockburst experiments is higher than that of similar compression experiment.

The expansion pressure of rammed batch and loose batch is studied as a function of the packing density, the moisture content, and the degree of crushing. The expansion pressure is found to depend on the gap between the rammed coal cake and the heating walls of the furnace chambers. [ABSTRACT FROM AUTHOR]

Abstract: The influence of olive paste preparation conditions on the triterpenic content of virgin olive oils from Arbequina and Picual cultivars was investigated. For this purpose, three sieve diameters of the hammer mill (4, 5, and 6mm), two malaxation temperatures (20 and 30°C), and two malaxation times (20 and 40min) were tested. Results obtained showed that for Arbequina oils, a finer crushing level resulted in higher maslinic acid and erythrodiol content. Increasing malaxing temperature and time lead to a rise in both oleanolic and maslinic acid concentration, whereas erythrodiol content increased only for the longer malaxation time. For Picual oils, higher concentrations of oleanolic acid, maslinic acid, and uvaol were obtained by prolonging the paste malaxation time. A finer crushing level resulted also in an increase of maslinic acid content. These findings suggest that virgin olive oil triterpenic composition can be improved by regulating olive paste preparation conditions. [Copyright &y& Elsevier]