The grinding of medical tablets is generally discouraged due to stability issues and various other issues. However, in specific scenarios directed by doctors, pharmacists may engage in grinding medical tablets, particularly to cater to pediatric or dysphagia patient populations as extra-label use. In the case of ground film-coated tablets, many film fragments arise in ground powder. Hence, the determination of the grinding endpoint for film-coated tablets is more challenging compared to uncoated tablets. The reports about grinding efficiency are limited because of the assumption that film-coated tablets are taken as tablets. The purpose of this report is to clarify how pharmaceutical excipients, particularly cellulose derivatives, utilized in film coating influence the grinding efficiency of film-coated tablets. Preliminary findings from the grinding of ten medical commercial tablets suggest that a higher concentration of hydroxypropyl methylcellulose (HPMC) correlated with increased difficulty in grinding film-coated tablets. Four film coating solutions with different HPMC-based components were used to coat model tablets prepared by the authors and their grindability was evaluated. The grinding of these film-coated tablets investigated those higher concentrations of HPMC resulted in increased tablet strength and larger residual film fragments. Moreover, the introduction of small quantities of additional plasticizer to the HPMC solution was found to decrease film strength, making the tablets more amenable to grind. It was shown that the components in the film coating solution affected the mechanical properties of the film and also the grinding characteristics of FC tablets.

The simulation using the Advanced Discrete Element Method-Computational Fluid Dynamics (ADEM-CFD) model analyzed the motion and breakage behavior of particles during wet ball milling in order to investigate the effects of the collision velocity and angle between two grinding balls on the particle grinding behavior. The analyses showed that the particles were more damaged when the grinding balls collided with a faster collision velocity in closer to a normal collision direction. The degree of the particle damage was quantified by the release energy, which was defined with the potential energy released by breaking the internal bonds of the particles. The release energy was strongly related to the normal components of the impact energy calculated from the collision velocity between two grinding balls.

Sessile organisms cause significant economic losses on submerged artificial surfaces such as ships. The use of tributyltin (TBT)-based antifouling paint for underwater ship hulls was banned due to its high toxicity to marine organisms. Therefore, it is necessary to develop low environmental impact antifouling technologies. Previously, antifouling studies focusing on the physiological and ecological understanding of fouling organisms has been conducted. And antifouling materials inspired by surface properties of marine organisms were developed in recent years. This review introduces the settlement selectivity and behavior of barnacle cypris larvae on the surfaces with different surface properties, such as micro-structures and functional groups.

Powder compression is the process of obtaining pellets by directly applying pressure to powder beds. The densification phenomenon involving the plastic deformation of particles is still unclear. In this study, the powder compression process of the binary mixture of powder with different plasticity was calculated by using the discrete element method incorporating Edinburgh elasto-plastic adhesion model. The macroscopic and microscopic powder properties were evaluated in the conditions of different volume fraction plastic powders. The calculation method of contact plasticity between elastic and plastic particles, which was proposed in this study, was validated by the data of experimental comparison tests. The result of this study indicated that particle plasticity strongly affected the powder properties, especially contact area inside the powder bed. We hope that this study will be useful for applications where the contact area inside the powder bed is important, such as batteries.

Using a horizontal batch dry bead mill newly developed by our company, talc raw material was ground in air, and its grinding performance and mechanochemical effect on the sample were evaluated from various perspectives. First, the average diameter of the ground product as a grinding performance decreases with the increase in grinding time or power source unit, reaching the submicron size. In addition, when mill operation is continued, talc changes fine particle aggregation and crystal structure change due to mechanochemical effects, and the phenomenon of detachment of the (OH) group around Mg in the crystals becomes remarkable. The flowability of the ground product is inhibited by the withdrawal of (OH) from the talc crystal, but this flowability is restored when it is dried. When the power source unit in the grinding approaches 3 kWh/kg, it asymptotes to the maximum value of 9% in the weight reduction percentage.