Packaging samples for irradiation Packaging samples for irradiation

Packaging samples for irradiation

Packaging samples for irradiation Overview • Care must be taken while packaging groundmass and mineral separates to prevent loss of sample and cross-contamination of adjacent samples. • Because the geometric position of samples and standards is critical, labelling throughout the process is important. • Sample packets are created, loaded with sample, put into disks, that are assembled together to be sent to the 1 MW reactor at Oregon State University.

Making aluminum packets • Irradiation packets are made at the time of packaging out of aluminum foil. • Packet size can be easily adjusted to different amounts of sample. • The bottom is sealed and the top is left open for loading.

Loading aluminum packets • Purified groundmass (shown) or mineral separates are carefully weighed and delivered into open end of packet. • Excess aluminum foil is removed, packet is then sealed and labelled.

Loading aluminum disks • Sealed packets are loaded into wells on 2. 5 cm diameter aluminum disks. • Well location (1 -9) in disk is recorded. • Irradiation # (UW###) and disk # (A, B, C…) is marked with a sharpie pen on the side of each disk. • Large grains (>1 mm) can be loaded without packets. • Neutron fluence monitor crystals (standards) are placed on top of packets in several of the wells.

Loading aluminum disks • For studies that require measurements of single crystals, different irradiation disks are used. • Sample # for each individual crystal must be carefully recorded on a disk map sheet. • Neutron fluence monitor crystals (standards) are loaded into every other well.

Assembling aluminum disks • Filled, labelled disks are stacked, secured with threaded aluminum studs and nuts. • Stacked disk assembly is placed into 2. 54 cm diameter aluminum Triga tube (supplied by Oregon State Univ. Radiation Center). • Triga tube is sent to the 1 MW reactor at Oregon State University.