OBJECTIVES One commonly used rat fracture model for bone and mineral research is a closed mid-shaft femur fracture as described by Bonnarens in 1984. Initially, this model was believed to create very reproducible fractures. However, there have been frequent reports of comminution and varying rates of complication. Given the importance of precise anticipation of those characteristics in laborato...

The costs related to comminution in the mineral industry are significant, thus representing main challenge for optimizing such a process. During last few decades, technology of High-Pressure Grinding Rolls (HPGR) has been consolidated as an important alternative circuits, due relatively low operational cost, well high energy efficiency. Due initial capital costs, HPGR applications limited high-...

Introduction: The chemical reactivity of lunar re-golith is one of the most important issues which impacts the human health and biological effects of lunar regolith. The constant micrometeorite bombardment of the lunar surface results in both comminution and shock melting of lunar regolith. In addition, radiation effects are likely to enhance the chemical reactivity of lunar regolith. With resp...

Extant rhinos are the largest extant herbivores exhibiting dietary specialisations for both browse and grass. However, the adaptive value of the wear-induced tooth morphology in rhinos has not been widely studied, and data on individual cusp and tooth positions have rarely been published. We evaluated upper cheek dentition of browsing Diceros bicornis and Rhinoceros sondaicus, mixed-feeding R. ...

The objective of this thesis is to optimise the fragmentation at Boliden Minerals open pit mine Aitik. Blasting is one of the main operations in mining, and its performance has a major impact on the overall economy of the mine. The fragmentation process affects not only the local productivity and unit costs of the mining department. It also affects the performance of the subsequent comminution ...

As a continuation of previous research work carried out to estimate the Bond index (wi) by using simulator based on cumulative kinetic model (CKM), deeper analysis was determine link between and energy parameters in case metalliferous non-metallic ore samples. The results evidenced relationship CKM parameter k grindability gbp; also with wi, obtained following standard procedure. An excellent c...

Fifty consecutive comminuted fractures of the femoral shaft were treated by closed unlocked intramedullary nailing. Twelve unstable fractures also had cast-bracing. There were no cases of infection or non-union, and satisfactory results were achieved in 38 fractures (76%). More severe comminution led to a higher incidence of unsatisfactory results, but malrotation deformity was seen more often ...