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The current research aimed to evaluate in vitro biological activities of green-synthesized silver nanoparticles using the Allium sativum clove extract. The stability of green-synthesized silver nanoparticles was evaluated via storage at 4°C, room temperature (37°C), and calcined at 300°C, 500°C, and 700°C. The antibacterial effect was evaluated using agar well, spread plate, biofilm reduction, and cell proliferation inhibition assays. The cytotoxic and antidiabetic effects were determined via brine shrimp lethality, protein kinase inhibition, and α-amylase inhibition assays. DPPH scavenging, iron-chelating, anticoagulant, and hemolytic effects were evaluated. The highest inhibition of Klebsiella pneumoniae was observed when freshly prepared, calcined (300°C), and stored nanoparticles (4°C and 37°C) were applied (9.66, 9.55, 7.33, and 6.65 mm) against freshly prepared and calcined at 700°C which showed the highest inhibition of Pseudomonas aeruginosa (8.55 and 7.66 mm). Cell viability assay, biofilm reduction assay, and spread plate method showed a significant antibacterial effect of freshly prepared silver nanoparticles. Freshly prepared and calcined nanoparticles at 300°C and 500°C possessed strong antioxidant and iron-chelating activity. Among all the synthesized silver nanoparticles, freshly prepared and calcined nanoparticles (300°C and 500°C) increases the prothrombin time. Silver nanoparticles possessed significant anticoagulant properties and less toxic at least concentration toward human RBCs. In brine shrimp lethality assay, freshly prepared nanoparticles showed a stronger toxic effect and caused high mortality of larvae. Protein kinase inhibition assay revealed that freshly prepared nanoparticles had the highest zone of inhibition (18.0 mm) at 50 µg/disc. Green-synthesized nanoparticles would be used as potential therapeutic agents to overcome both infectious and noninfectious diseases.

In this paper, numerical approach has been implemented to depict the promising efficacy of dispersion of alumina nanoparticles for expedition of freezing. The fraction and volume of powders were assumed as variables to evaluate the performance of system. The tank has sinusoidal shape and triangular cold surface has been applied as origins of solidification. The use of adaptive grid leads to better capturing the regions with higher gradient of scalar which gives higher accuracy of modeling. The precision of simulation was checked with associating the outcomes with previous data and good accommodation was reported. As alumina added in water, the period of process declines around 41.18% and optimized size of powder with highest concentration has been utilized. The time changes from 197.25 s to 157.91 s if the d p changes from 30 nm to 40 nm. By changing the radius of powder from 15 nm to 25 nm, the required time augments around 19.33% when ϕ = 0. 0 4. [ABSTRACT FROM AUTHOR]

Summary: In March 2015, the Kingdom of Saudi Arabia signed an agreement with South Korea to build the system‐integrated modular advanced reactor (SMART) originally developed by the Korean Atomic Energy Research Institute. The SMART is a structurally contained safe dual‐purpose power plant reactor that produces both electricity and desalination. This study aims to design a double‐containment structure with a pool‐type concept to enhance the SMART safety and develop a robust design for future modular reactors. For that purpose, a theoretical model is developed herein, which leads to the modeling of a double‐containment structural design of a water pool. The model calculates various parameters (ie, temperature, pressure, phasic velocities, and condensable gases) and is used to develop a simulation program for use in a computational assessment. Moreover, two best‐estimate thermal hydraulic engineering programs, namely THEATRe and RELAP5, are used to simulate the original SMART with the double‐containment water pool structure. The differences in the modeling strategies of the two simulation techniques are discussed to accurately measure various technical parameters. Accordingly, a nodalization diagram of the reactor and the pool‐type concept are developed and simulated. The results obtained from the computational models yield the error of >2%, depicting accuracy. A small‐break loss of coolant accident is also simulated to mitigate the transient conditions. The result verifies the adoptability of this reactor concept in any other small modular reactor. [ABSTRACT FROM AUTHOR]