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We have constructed a bidirectional and efficient converter between microwave and optical light using a mechanically compliant membrane coupled via the optomechanical interaction. Ongoing work towards quantum state transfer is discussed.

We demonstrate efficient mechanically-mediated transduction between microwave and optical signals using a micromechanical SiN membrane. This interface has the potential to transform information between these vastly different frequencies while maintaining a fragile quantum state.

Humid-air and aqueous general and pitting corrosion models (including their uncertainties) for the carbon steel outer containment barrier were developed using the corrosion data from literature for a suite of cast irons and carbon steels which have similar corrosion behaviors to the outer barrier material. The corrosion data include the potential effects of various chemical species present in the testing environments. The atmospheric corrosion data also embed any effects of cyclic wetting and drying and salts that may form on the corroding specimen surface. The humid-air and aqueous general corrosion models are consistent in that the predicted humid-air general corrosion rates at relative humidities between 85 and 100% RH are close to the predicted aqueous general corrosion rates. Using the expected values of the model parameters, the model predicts that aqueous pitting corrosion is the most likely failure mode for the carbon steel outer barrier, and an earliest failure (or initial pit penetration) of the 100-mm thick barrier may occur as early as about 500 years if it is exposed continuously to an aqueous condition at between 60 and 70°C.

A detailed stochastic waste package degradation simulation model was developed incorporating the humid-air and aqueous general and pitting corrosion models for the carbon steel corrosion-allowance outer barrier and aqueous pitting corrosion model for the Alloy 825 corrosion-resistant inner barrier. The uncertainties in the individual corrosion models were also incorporated to capture the variability in the corrosion degradation among waste packages and among pits in the same waste package. Within the scope of assumptions employed in the simulations, the corrosion modes considered, and the near-field conditions from the drift-scale thermohydrologic model, the results of the waste package performance analyses show that the current waste package design appears to meet the ‘controlled design assumption’ requirement of waste package performance, which is currently defined as having less than 1% of waste packages breached at 1,000 years [1]. It was shown that, except for the waste packages that fail early, pitting corrosion of the corrosion-resistant inner barrier has a greater control on the failure of waste packages and their subsequent degradation than the outer barrier. Further improvement and substantiation of the inner barrier pitting model (currently based on an elicitation) is necessary in future waste package performance simulation model.

The noise radiation characteristics of a 70‐ton semihermetic, twin‐screw compressor are examined under controlled laboratory conditions to identify the mechanisms of noise generation. Results indicate that a majority of the acoustic radiation occurs at the first six harmonics of the fundamental screw frequency of refrigerant gas compression and discharge. Compressor sensitivity studies are performed to correlate changes in the noise radiation characteristics and internal gas pulsations with variations in select operating parameters of the compressor. Sensitivity tests suggest that the primary mechanisms of noise generation are discharge gas pulsations, rotor chatter, and flow noise. Discharge gas pulsations, which are created by a mismatch between the chamber pressure and discharge pressure, are significant at all capacities. At low capacities, the reduced refrigerant flow rates and oil circulation decreases the gas cushion between the twin rotors, consequently promoting rotor chatter. Conversely, at high...