Several media report highlight on that the pharmaceutical companies require ultra-low temperatures −80˚C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per Montréal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard.

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Insertion of Sustainable Development Goals (SDGs) into higher education is an important concern. This article aims to address the influences of SDGs in higher and engineering educational system in Egypt. The present study focuses on SDGs 3, 4, 6, 7, 9, and 11. SDG 3 is related to occupational health and SDG 4 is related to higher education development. However, SDGs 6, 7, 9, and 11 are related to both mechanical and environmental engineering, and occupational safety. The study approach involves case risk analysis, investigations, and review for design concepts of occupational health and safety before and after the Coronavirus disease . A number of cross-sectional studies that constitute 125 multidisciplinary research plans (MDRPs) are grouped to monitor and evaluate two main factors which are an influence of involving SDGs into engineering education and selected curriculum of occupational health and safety. Then the results of these research-based studies, which performed over four academic years started from 2017 up to date 2021, are depicted and discussed. These results reveal the importance of interlink between engineering education and the intended SDGs. The latest 25 MDRPs demonstrate that Egypt response to alleviate the COVID-19 is rapidly pronounced specially on SDGs 3 and 4 simultaneously. However, those MDRPs show that neither record impacts nor delays on SDGs 6, 7, 9 and 11. The conclusions prioritize both the advanced educational mechanisms and verify the engineering curriculums to raise awareness of SDGs among both staff members and students in Egyptian universities. Finally, future work is recommended at the end of this article to focus on each specific goal to gain deep insight to state of the art for each SDG around globe using education development.

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