The bimetallic Pd-Cu nanocatalysts with different Pd loadings and ultrasonic irradiation times were sonochemically synthesized and their activities toward CO oxidation were investigated. XRD, FESEM, TEM, BET, FTIR and TG-DTG techniques were employed in nanocatalysts characterization. XRD data confirmed formation of CuAl2O4 spinel with an average crystallite size of 4.9 nm. FESEM images revealed more uniform pattern and also fewer agglomerations were observed by increasing ultrasonic irradiation time. In agreement with FESEM result, TEM images depicted nanoparticles and uniform dispersion of active phase over alumina. BET surface analysis showed that increasing the Pd loading has no significant effect on surface area; whereas by increasing irradiation time the surface area increases slightly. Catalytic performance tests of synthesized samples showed that Pd(1.5%)-Cu(20%)/Al2O3 with 95 min ultrasonic irradiation time had the best activity over the course of reaction. In addition, increasing CO at feed composition revealed that among synthesized nanocatalysts with 0.5%, 1% and 1.5% of Pd, synthesized sample with 1.5% of Pd had the best low-temperature activity.

Two 3-bed 5-step and two 4-bed 7-step continuous feed pressure swing adsorption (PSA) cycle schedules were systematically devised and studied via simulation for producing high-purity O 2 (≥99.5 vol %) at high recovery using a carbon molecular sieve (CMS). Two binary (O 2 :Ar) and two ternary (O 2 :Ar:N 2 ) feed mixtures were investigated to mimic the product produced from a typical O 2 PSA system. In addition to feed composition, the effects of light end (LE) versus heavy end (HE) equalization (Eq), two sequential Eq steps versus Eq followed by forced cocurrent depressurization (CoD)/light end pressurization (LEP) steps, feed flow rate (i.e., feed throughput θ), cycle time (t c ), Eq step valve coefficient (C v ), and countercurrent depressurization (CnD) step C v on the process performance were studied in terms of O 2 purity (Pur, vol %), O 2 recovery (Rec, %), and θ (L STP , h/kg). In descending order, the best performance from each cycle was Pur = 99.5, Rec = 93.3, and θ = 455.7 for a 4-bed 7-step PSA cycle with LE Eq and forced CoD/LEP (III); Pur = 99.6, Rec = 85.7, and θ = 471.4 for a 4bed 7-step cycle with two LE Eqs (II); Pur = 99.5, Rec = 77.4, and θ = 1089.5 for a 3-bed 5-step cycle with LE Eq (Ia); and Pur = 99.5, Rec = 68.7, and θ = 628.6 for a 3-bed 5-step cycle with HE Eq (Ib). The two C v values exhibited only marginally unfavorable effects on Pur at smaller values. All four cycles were very sensitive to both t c and θ, with Pur decreasing and Rec increasing with decreasing θ, and Rec decreasing and Pur exhibiting a maximum with increasing t c . For cycle III, the Pur exhibited a maximum with a change in the CoD end pressure, with more negative effects on Pur at longer t c . Changing the levels of Ar or N 2 in the feed at fixed O 2 content had essentially no effect on Pur or Rec, while decreasing the level of O 2 in the feed had an almost proportionally negative effect on Pur and no effect on Rec. When N 2 was replaced with Ar in the feed, an unexpected equilibrium effect counteracted an expected kinetic effect, producing a counterintuitive negative result on Pur.

Caffeine was encapsulated into calcium alginate microcapsules, and these microcapsules were produced with four types of material – starch, xanthan, chitosan, and whey protein isolate – in combination with alginate. Formulation characteristics such as the efficiency of microencapsulation, microcapsule size, viscosity, and texture properties of the microcapsules have been evaluated. The release of caffeine from different microcapsules was conducted in simulated saliva fluid. Alginate microcapsules with chitosan coating provided the slowest release of caffeine, compared with the other microcapsules. Significant differences in the appearance of the microcapsules were detectable by scanning electron microscopy (SEM) and optical microscopy. Fourier‐transform infrared spectrometry (FTIR) analysis confirmed the existence of carbonyl groups in caffeine‐loaded microcapsules, and differential scanning calorimetry (DSC) thermograms indicated the glass transition temperature of the microcapsules. This study showed that the microencapsulation of caffeine with alginate may be helpful for designing fast (alginate) as well as prolonged caffeine release (alginate–starch–xanthan with chitosan).

Two types of probiotics (Lactobacillus casei and Bifidobacterium bifidum) were added to mayonnaise sauce as either free cells or encapsulated with resistant starch. The survival of L. casei and B. bifidum was evaluated during the product storage for 30 days at 4°C. The viability of B. bifidum cells disappeared in the free state after 10 days; however, free L. casei approximately decreased 6 log cycles in a number of cells after 30 days storage at 4°C. When the L. casei and B. bifidum were encapsulated in calcium alginate capsules with Hi-Maize starch, the viable cell numbers were decreased to 1.3 × 10 7 and 9 × 10 5 CFU/g, respectively. In general, the results showed that encapsulation with resistant starch can significantly enhance the survival of probiotic bacteria in mayonnaise sauce during storage. No differences were detectable in the morphology of capsules by scanning electron microscopy and optical microscopy. Sensory qualities of mayonnaise sauce were improved by the addition of encapsulated probiotic bacteria.

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