Security Performance Analysis of Downlink Double Intelligent Reflecting Surface Non-Orthogonal Multiple Access Network for Edge Users.

In this work, we study the security performance of a double intelligent reflecting surface non-orthogonal multiple access (DIRS-NOMA) wireless communication system supporting communication for a group of two NOMA users (UEs) at the edge, with the existence of an eavesdropping device (ED). We also assume that there is no direct connection between the BS and the UEs. From the proposed model, we compute closed-form expressions for the secrecy outage probability (SOP) and the average security rate (ASR) for each UE.

Biosorption and biodegradation of a sulfur dye in high-strength dyeing wastewater by Acidithiobacillus thiooxidans.

The ability of the bacterial strain Acidithiobacillus thiooxidans to remove sulfur blue 15 (SB15) dye from water samples was examined. This bacterium could not only oxidize sulfur compounds to sulfuric acid but also promote the attachment of the cells to the surface of sulfidic particles, therefore serving as an efficient biosorbent. The biosorption isotherms were better described by the Langmuir equation than by the Freundlich or Dubinin-Radushkevich equation.