Few Palaeogene and Neogene sediment cores from the Antarctic continental margin have been dated with sufficient precision to enable establishment of direct linkages between glacial events on the Antarctic continent and marked events in deep-sea N18O records. As a result, much of our knowledge of the gradual, but stepwise, shift from ‘greenhouse’ climates of the Cretaceous to the ‘ice-house’ cli...

Synchrotron powder X-ray diffraction data are used to determine the core electron deformation of diamond. Core shell contraction inherently linked to covalent bond formation is observed in close correspondence with theoretical predictions. Accordingly, a precise and physically sound reconstruction of the electron density in diamond necessitates the use of an extended multipolar model, which aba...

Experiments were performed to determine the extent of penetration of drill water into Grouse Canyon densely welded t ff during use of normal drilling practices. Core samples were examin d from a borehole cored in a rib of the Rock Mechanics drift in G Tunnel at the Nevada Test Site, Nye County, Nevada. Methylene blu dye was added to the drill water to act as a tracer which stained the rock blue...

Drill-core samples are a key component in mineral exploration campaigns, and their rapid objective analysis is becoming increasingly important. Hyperspectral imaging of drill-cores non-destructive technique that allows for non-invasive fast mapping phases alteration patterns. The use adapted machine learning techniques such as supervised algorithms robust accurate drill-core hyperspectral data....

Carbon isotope compositions of organic matter in fine-grained siliciclastic units deposited above and below glacial diamictite at the base of the ca. 2.45–2.22 Ga Huronian Supergroup in Ontario, Canada were studied to constrain relationships between profound fluctuations in the exogenic carbon cycle and dramatic climate changes at the beginning of the Proterozoic Eon. In both drill core and out...

This work explores light delivery optimization for photoacoustic-guided minimally invasive surgeries, such as the endonasal transsphenoidal approach. Monte Carlo simulations were employed to study three-dimensional light propagation in tissue, comprising one or two 4-mm diameter arteries located 3 mm below bone, an absorbing metallic drill contacting the bone surface, and a single light source ...

Drilling is the most frequently employed operation of secondary machining for fiber-reinforced materials owing to the need for joining structures. Delamination is among the serious concerns during drilling. Practical experience proves the advantage of using such special drills as saw drill, candle stick drill, core drill and step drill. The experimental investigation described in this paper exa...