Abstract: A blockchain-based exchange system includes a distributed group of computers operating a distributed consensus algorithm and having a distributed ledger. The system enables trades to be recorded on the distributed ledger. The system performs operations including receiving, from a first user, a deposit of a first value, converting the first value into a first pool token, adding the first value to a first pool, receiving, from a second user, a deposit of a second value.

Abstract: The present disclosure provides an apparatus for characterizing mechanical properties of a sample. The apparatus comprises a structure for supporting the sample and applying a first pressure in a first direction to the sample and an actuator for modulating the first pressure. The apparatus also comprises a pressure applicator containing a liquid and arranged to apply a second pressure to the sample in a second direction that is transversal to the first direction. Further, the apparatus comprises a pore pressure applicator arranged to apply a flow of a fluid through a porous sample such that a pore pressure is applied to the porous sample. In addition, the apparatus comprises a sensor for sensing a change in the sample in response to a change in a pressure experienced by the sample.

Abstract: A method for determining the density of cement slurry in undersea drilling is disclosed. The method uses the reflection of acoustic waves from the slurry in order to determine its acoustic impedance and thus its density.

Abstract: The present disclosure provides an apparatus for characterising mechanical properties of a sample. The apparatus comprises a structure for supporting the sample and applying a first pressure in a first direction to the sample and an actuator for modulating the first pressure. The apparatus also comprises a pressure applicator containing a liquid and arranged to apply a second pressure to the sample in a second direction that is transversal to the first direction. Further, the apparatus comprises a pore pressure applicator arranged to apply a flow of a fluid through a porous sample such that a pore pressure is applied to the porous sample. In addition, the apparatus comprises a sensor for sensing a change in the sample in response to a change in a pressure experienced by the sample.

Abstract: A method for determining the density of cement slurry in undersea drilling is disclosed. The method uses the reflection of acoustic waves from the slurry in order to determine its acoustic impedance and thus its density.

Abstract: Permeation of water between inner and outer insulating jackets of an elongate electrical heater or other device along a metallic braid between the jackets is limited by means of a water-blocking section. The water-blocking section is generally placed near the connected end of the device to prevent water from reaching the connection. In the water-blocking section, the outer jacket is removed and an insulating sleeve, preferably a heat-shrunk polymeric sleeve, is placed over the exposed length of the inner jacket and the ends of the outer jacket. A water-proof sealing material is placed between the sleeve and part only of the exposed inner jacket. In this way, water which permeates between the jackets to the water-blocking section is prevented from passing through the section but is permitted to escape from the device.