The thermal and mechanical properties of a new negative photoresist, SU8, were characterized. The influence of curing conditions, such as baking temperature, baking time and UV dosage, on the thermal and mechanical properties of the resultant coatings was studied in detail. It was found that the glass-transition temperature (T g) of the coatings was coincident with the baking temperature over the temperature range of 25 • C-220 • C for coatings being baked for just 20 min. However, the T g reached a limiting value (about 240 • C) once the cross-linking reaction was complete, and would not increase further with the baking temperature. The peak temperature of the dimension versus temperature plots, where heat shrinkage occurred, was about a factor of 1.16 times higher than the baking temperature for the temperature range studied. Both the T g and the shrinkage temperature were affected by the baking time. The thermal expansion coefficients (TEC), including the volumetric TEC (α v), the in-plane TEC (α 1) and the out-of-plane TEC (α 2), were measured by a pressure-volume-temperature (PVT) apparatus and thermal-mechanical analyzer (TMA). Great residual stress could be generated during the process, and the change in residual stress with the environmental humidity was investigated using vibrational holographic interferometry.

Bitumen froth treatment is an integrated process step in the Athabasca oil sands bitumen recovery operations. Its objective is to separate mineral solids and water from the bitumen froth. The bitumen froth is diluted with naphthenic or paraffinic solvents to lower its viscosity to facilitate the separation; therefore, bitumen froth treatment is the removal of inorganics (mineral particles and water droplets) from a bitumen organic solvent solution. The micrometer sized mineral particles (mainly clays) and water-in-oil emulsion droplets are the most difficult to remove from the bitumen froth. Research has been carried out that has led to an understanding of the formation, stabilization and properties of the water-in-oil emulsions in the bitumen organic solvent solution. It is known that the water-in-oil emulsions are formed by water entrained into the bitumen froth during the water-based extraction process and stabilized by natural surfactants in bitumen (especially asphaltene) and fine mineral particles. In fact, the fine mineral particles are the main detriments in stabilizing the water-in-oil emulsions, for the emulsified water droplets were found to be easy to destabilize and remove in the absence of fine mineral particles. Effective removal of the fine mineral particles and water droplets requires both (1) that the fine mineral particles form larger aggregates and (2) that the water-in-oil emulsions can be destabilized. Different demulsifiers have been studied in froth treatment, but the focus was more on the “surfactant-stabilized” water-in-oil emulsions. Therefore, this approach can only partly contribute to item (2). No efforts were made to aggregate the fine mineral particles. Therefore, it was proposed that a possible approach for the effective bitumen froth treatment would be to develop and use process aids that can both aggregate the fine mineral particles and destabilize the water-in-oil emulsions. Several other potential directions to improve bitumen froth treatment have also been pointed out based on the literature review.

Memory cells have always been an important element of information technology. With emerging technologies like big data and cloud computing, the scale and complexity of data storage has reached an unprecedented peak with a much higher requirement for memory technology. As is well known, better data storage is mostly achieved by miniaturization. However, as the size of the memory device is reduced, a series of problems, such as drain gate‐induced leakage, greatly hinder the performance of memory units. To meet the increasing demands of information technology, novel and high‐performance memory is urgently needed. Fortunately, emerging memory technologies are expected to improve memory performance and drive the information revolution. This review will focus on the progress of several emerging memory technologies, including two‐dimensional material‐based memories, resistance random access memory (RRAM), magnetic random access memory (MRAM), and phase‐change random access memory (PCRAM). Advantages, mechanisms, and applications of these diverse memory technologies will be discussed in this review.

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