Abstract: Radiation shielding and methods of manufacture are disclosed. A radiation shielding apparatus includes a matrix including matrix material; and a mixture positioned in the matrix, the mixture including: a neutron thermalizing material; and a neutron absorbing material mixed with the neutron thermalizing material. A reactivity control system includes a container rotatable around an axis; a divider positioned inside the container to define two or more compartments within the container; at least one neutron absorber positioned in at least one of the two or more compartments; and at least one neutron reflector positioned in another of the two or more compartments that is fluidly isolated from the at least one of the two or more compartments. A method of manufacturing radiation shielding material includes: fabricating a matrix; generating a mixture by mixing a neutron absorbing material, a neutron thermalizing material, and additive materials; and loading the mixture into the matrix.

Abstract: A bioreactor can include a plurality of unit cells. Each unit cell can include a floor configured to support a volume of liquid, the floor being symmetric across at least one axis of symmetry, and an injection port oriented at a center point of at least one axis of symmetry and configured to inject a fluid into the volume of liquid. The bioreactor can also include a peripheral side wall surrounding the plurality of unit cells such that the volume of liquid is retained in the bioreactor.

Abstract: A bioreactor can include a plurality of unit cells. Each unit cell can include a floor configured to support a volume of liquid, the floor being symmetric across at least one axis of symmetry, and an injection port oriented at a center point of at least one axis of symmetry and configured to inject a fluid into the volume of liquid. The bioreactor can also include a peripheral side wall surrounding the plurality of unit cells such that the volume of liquid is retained in the bioreactor.