Abstract: Plurality of layers form a nuclear fission reactor structure, each layer having an inner segment body, an intermediate segment body, and an outer segment body (each segment body separated by an interface). The layers include a plurality of cladding arms having involute curve shapes that spirally radiate outward from a radially inner end to a radially outer end. Chambers in the involute curve shaped cladding arm contain fuel compositions (and/or other materials such as moderators and poisons). The design of the involute curve shaped cladding arms and the composition of the materials conform to neutronic and thermal management requirements for the nuclear fission reactor and are of sufficiently common design and/or have sufficiently few variations as to reduce manufacturing complexity and manufacturing variability.

Abstract: Provided herein are neutron imaging systems (e.g., radiography and tomography) systems and methods that provide, for example, high-quality, high throughput 2D and 3D fast or thermal neutron and/or X-ray images. Such systems and methods find use for the commercial-scale imaging of industrial components. In certain embodiments, provided herein are system comprising a plurality of independent neutron absorber-lined collimators (e.g., 4 or more collimators) extending outwards from a central neutron source assembly.

Abstract: A marine hydrokinetic electric power or wind power generator may have three modules: a harnessing module, a controlling module, and a generating module. The harnessing module may have one of a propeller and a waterwheel for receiving wind or water energy. The controlling module may have a gearbox comprising gears for matching the expected wind or water generating power to an output power, a control motor, and a three variable gear assembly. The three variables are a variable input, a constant output and a constant speed control motor input variable. The variable input is received from the harnessing module and the constant output is delivered to an electricity generator. A generating module (generator) generates output power which may be a multiple of ten times the power rating of the controlling module (the constant speed control motor).

Abstract: A high flux reactor is comprised of a core which is divided into two symetric segments housed in a pressure vessel. The core segments include at least one radial fuel plate. The spacing between the plates functions as a coolant flow channel. The core segments are spaced axially apart such that a coolant mixing plenum is formed between them. A channel is provided such that a portion of the coolant bypasses the first core section and goes directly into the mixing plenum. The outlet coolant from the first core segment is mixed with the bypass coolant resulting in a lower inlet temperature to the lower core segment.

Abstract: Gas-cooled nuclear reactors include circulation systems for cooling gas to remove the heat generated in the reactor core. An improved arrangement includes a plurality of steam generators in a horizontal plane located above the horizontal plane of the reactor core. The cooling gas circulates from the bottom of the reactor core to the top. Improved heat removal is accomplished in this manner as the heated cooling gas enters the steam generators after passage through the reactor core without undergoing further circulation in a horizontal or inverse vertical direction.