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Influence of carbon sources and biosurfactants on selenite and lead bioremediation by Enterococcus sp
(Elsevier, 2026-01) Tendenedzai, Job Tatendan; Chirwa, Evans N.M.; Brink, Hendrik Gideon; job.tendenedzai@tuks.co.za
Please read abstract in the article.
Barriers to cyber hygiene in hybrid work environments : a case study of a Lesotho development parastatal
(Central European Conference on Information and Intelligent Systems, 2025-09) Nkhabu, Lebohang Alexis; Matthee, Machdel C.; machdel.matthee@up.ac.za
This study’s objective is to investigate the barriers to maintaining effective cyber hygiene in hybrid work environments, focusing on a case study within a development parastatal in Lesotho. The shift to hybrid work models, accelerated by the COVID-19 pandemic, has introduced new vulnerabilities in cybersecurity, particularly regarding remote work. Utilizing qualitative, research through interviews with IT specialists, managers, and end-users, the study identifies key barriers confirming themes found in literature affecting cyber hygiene in companies namely, user characteristics (such as awareness and attitude),environmental support (awareness and training, policies, leadership, ICT support) and environmental characteristics (organisational culture, poor infrastructure). It is shown that the developing country context of the parastatal exacerbate these barriers.
Effects of strain and inter-pass time on the restoration behavior of 436 stainless steels
(Springer, 2025-11) Salojee, Muhammed Yusuf; Siyasiya, Charles Witness; Annan, Kofi Ahomkah; Moema, Joseph S.; u13271050@tuks.co.za
Ferritic stainless steels (FSSs) are viable alternatives to nickel containing austenitic stainless steels. The AISI 436 FSS grade is fully ferritic at all temperature ranges, and therefore, grain refinement can only be achieved through controlling inclusions during solidification and/or recrystallization. In this work, the effects of strain and inter-pass time on the restoration behavior of 436 were systematically investigated using the Gleeble 1500 thermomechanical processing simulator. The aim of the study was to promote the accumulation of strain by delaying recrystallization during roughing rolling simulation to improve the driving force for recrystallization during finishing rolling simulation at lower temperature. Three roughing rolling schedules were designed, i.e., the first simulated the existing industry practice (Control), the second with increased inter-pass time (INT) and the last with both increased inter-pass time and strain per pass (INT + S). Roughing and finishing were each simulated in three-passes, amounting to a total of six-passes. The SEM-EBSD results revealed that the Control and INT schedules resulted in higher strain localization, particularly around particles. On the contrary, the increased inter-pass times and strains (INT + S) led to less strain accumulation. Annealing after roughing rolling simulation led to the nucleation of fine grains in the Control, which suggests that delaying finishing rolling would promote recrystallization and the breakdown of the cast structure.
Microstructure and mechanical properties evaluation of high Ti-V microalloyed steel after coiling process at different temperatures in a hot strip rolling simulation process
(Springer, 2025-08) Jafarpour Rezaei, Seyed Reza; Siyasiya, Charles Witness; Tang, Zhenghua; Moema, Joseph
Today, reducing greenhouse gas emissions is a crucial concern, making the development of steel alloys with optimal desired properties and reduced weight an urgent priority, especially in automotive industries, as it leads to decreased fuel consumption, hence the continued interest in developing high-strength low-alloy steels (HSLA). In this research, the impact of coiling temperature on the final microstructure and mechanical properties of Ti-V HSLA microalloyed steel was investigated. The Gleeble 1500 was used to simulate the hot rolling and coiling processes. The results indicated that reducing coiling temperatures led to a transition in microstructures from polygonal ferrite and pearlite to acicular ferrite and bainite. The optimal coiling temperature for achieving high diffusion rates of microalloying elements and optimal precipitation kinetics to form nanosized precipitates was determined to be 650 °C, where the smallest precipitates were observed of 30 nm. However, the specimen subjected to a lower coiling temperature of 550 °C exhibited the highest yield stress (781 MPa), ultimate tensile strength (971 MPa), and hardness (324 HV), which were attributed to microstructural characteristics such as high dislocation density and a finer grain size of 3 µm compared to 6 µm at 700 °C.
Tuning optoelectronic properties of CsPbI2Br perovskite films via octadecyl ammonium iodide substitution
(Springer, 2025-11) Thubane, Sandile Job; Nombona, Nolwazi; Diale, M. (Mmantsae Moche); mmantsae.diale@up.ac.za
Please read abstract in the article.