Low pressure (,10s mTorr), high plasma density (.10 cm) reactors are rapidly becoming the tool of choice for etching during microelectronics fabrication. Although gas injection and pumping are well characterized process parameters in higher pressure systems, the impact of the symmetry of gas injection and pumping on the uniformity of reactant fluxes to the substrate are less well known in low p...

Practical application of thermionic space nuclear power systems necessitates the investigation of such systems responses to changes in operation and design parameters as well as load-following characteristics. The principle building block in these systems is the thermionic fuel element (TFE). A Thermionic Transient Analysis Model (TUAM) is developed to simulates transient and steady-state opera...

This short note traces the events that led to the unsymmetric rank one formula known as the “good Broyden” update [5,6], which is widely used within derivative-free mathematical software for solving a system of nonlinear equations. I left University in 1956 with an indifferent degree in Physics and took up a post with the English Electric Company in Leicester. The company was involved in the de...

Analysts and decision makers frequently want estimates of the cost of technologies that have yet to be developed or deployed. Small modular reactors (SMRs), which could become part of a portfolio of carbon-free energy sources, are one such technology. Existing estimates of likely SMR costs rely on problematic top-down approaches or bottom-up assessments that are proprietary. When done properly,...

This paper presents the designing of a power quality compensator to solve the power quality problem of negative-sequence and harmonic currents in high-speed railway traction systems. The proposed power quality compensator is constituted by railway static power conditioner (RPC), two thyristor-controlled reactors and two thyristor-controlled 3filters. The RPC contains two converters which are co...

This paper presents the results of an investigation into the treatment of Tehran Refinery effluents in UASB reactors. Four pilot-scale UASB reactors were built with similar dimensions, each with a volume of 45.78 1, and operated in parallel at 37 °C. The sludge seed was prepared from the waste activated sludge of the wastewater treatment unit of the refinery. The organic loading rates were grad...

Extremophiles thrive in ice, boiling water, acid, the water core of nuclear reactors, salt crystals, and toxic waste and in a range of other extreme habitats that were previously thought to be inhospitable for life. Extremophiles include representatives of all three domains (Bacteria, Archaea, and Eucarya); however, the majority are microorganisms, and a high proportion of these are Archaea. Kn...

One of the techniques of minor actinides transmutation is to recycle these nuclides into fission reactors. Two concepts of a minor actinides burner reactor with very hard neutron energy spectrum as well as very high neutronjlux me discussed. The fuel cycle facilities for these burner reactors am assessed to discuss the technical feasibili~ of these reactors. Transmutation of minor actinide in b...

Materials and core components for the next generation power reactors technologies require testing that can be performed in existing research reactors. Such experiments employ devices dedicated to reflect relevant thermal neutron parameters simulating conditions present in, example, but not limited to, HTGR A novel thermostatic irradiation device named ISHTAR (Irradiation System High-Temperature...