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By analyzing the threshold-jumping of Schmitt circuits, this paper indicates that the core element realizing this function in binary TTL Schmitt circuits is the differential current switch with controllable threshold. Based on the characteristic having two kinds of signal-detection threshold in ternary TTL circuits, a ternary TTL Schmitt circuit having twice reactions of threshold-jumping is designed. The simulation with PSPICE proves that the designed circuit has ideal function of Schmitt circuits.

Environment-responsive membranes were created by modification of a commerical polyvinylidene fluoride (PVDF) membrane support with a thermo-responsive hydrogel composed of poly N-vinyllactams cross-linked with bisacrylamide. The modified membranes were then characterized by their percentage mass gains as well as by their valve effect in response to changes in salt concentration. One set of membranes, with a large valve effect, was selected for highest retention of intermediately sized proteins was examined for ultrafiltration-based protein separation applications. A batch separation protocol featuring pulsed sample injection technique (PSIT) was then used to sieve single proteins and to fractionate a synthetic binary protein mixture and a synthetic ternary protein mixture with some success, demonstrating the potential of these environment-responsive membranes for use in multi-component separations. A second set of membranes, with a small valve effect, was selected for its ability to alter between hydrophobic and hydrophilic states under different environmental conditions and its potential in hydrophobic interaction membrane chromatography (HIMC) applications was successfully demonstrated by comparing against a benchmark membrane that is used successfully for HIMC applications in prior literature. Thesis Master of Applied Science (MASc)