Weight on bit downhole MWD sensors can measure weight-on-bit more accurately and transmit the data to the surface. Weight on bit Weight on bit (WOB), as expressed in the oil industry, is the amount of downward force exerted on the drill bit and is normally measured in thousands of pounds. Weight on bit is provided by drill collars, which are thick-walled tubular pieces machined from solid bars of steel, usually plain carbon steel but sometimes of nonmagnetic nickel-copper alloy or other nonmagnetic premium alloys. Gravity acts on the large mass of the collars to provide the downward force needed for the bits to
Isotopes of tennessine Isotopes of tennessine Tennessine (Ts) is the most-recently synthesized synthetic element, and much of the data is hypothetical. As for any synthetic element, a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first (and so far only) isotopes to be synthesized were Ts and Ts in 2009. The longer-lived isotope is Ts with a half-life of 51 ms. The below table contains various combinations of targets and projectiles that could be used to form compound nuclei with atomic number 117. Between July 2009 and February 2010, the team at the JINR (Flerov