We report the first accuracy evaluation of NRC-FCs2, an atomic fountain clock developed at the National Research Council Canada. The short term stability at high atomic density is 1.1 × 10 −13 at 1 second of averaging time. The typical overall fractional type B uncertainty is 2.3 × 10 −16 . GNSS-based frequency comparisons of NRC-FCs2 with the SI second, as reported by the BIPM over fourteen months, give a fractional frequency difference of −2.4(3.7) × 10 −16 .

The feasibility to achieve deep penetration welding of stainless steel utilising a 15 kW laserline® diode laser has been studied. This was approached by first characterising the properties of melt run welds on stainless steel 304L plates and then transferring the gained knowledge to perform the butt welds. The results from the melt run analysis indicated that there was an increase in penetration and weld width with heat input, i. e. with either increasing the laser power (9 to 15 kW) or decreasing the welding velocity (3 m/min to

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