Comparative study of NiO/CuO/Ag doped graphene based materials for reduction of nitroaromatic compounds and degradation of dye with statistical study.

In the present work, the Nickel oxide (rGO-NiO), Silver (rGO-Ag), Copper oxide (rGO-CuO) doped Graphene Oxide are reported for catalytic reactions. A comparative study for catalytic activities of these materials are performed with nitroaromatic compound 4-nitroaniline and the results are statistically studied by using univariate analysis of variance and Post Hoc Test through Statistical Package for Social Sciences and it is observed that CuO doped Graphene material is showing better catalytic activity in minimum time. So, further research has been focused on the catalytic acitivity of rGO-CuO only and it is found that it is efficient in reducing other nitro compounds also such as Picric acid and Nitrobenzene. Dye degradation of Methylene blue is also performed using CuO decorated Graphene material and significant changes were observed using UV spectroscopy. The characterization of rGO-CuO is done with Fourier-transform Infrared Spectroscopy, Powder X-ray Diffraction, Thermogravimetric Analysis, Scanning Electron Microscope and Transmission Electron Microscopy.

Biodegradation of di-2-ethylhexyl phthalate by Bacillus firmus MP04 strain: parametric optimization using full factorial design.

Di-2-ethylhexyl phthalate (DEHP) is used as a plasticizer in making plastics and released from landfills. This study attempted to degrade DEHP using microbial isolates. Isolates of Bacillus spp. were tested for their efficacy in degrading DEHP. Degradation was assessed using liquid chromatography-mass spectrometry (LC-MS). The most efficient DEHP degradation was achieved by Bacillus firmus MP04, which has been identified as Bacillus firmus MP04. This strain was found to use DEHP as the sole source of carbon without carbon source supplementation. Full factorial design was used to optimize the conditions for DEHP degradation which revealed the suitability of pH 7, 5% salt concentration, 20 to 37 °C temperature, and yeast extract as a nitrogen source. LC-MS elucidated the possible degradation mechanism via benzoic acid formation. However, prolonged incubation formed a typical compound denatonium benzoate due to reactions with other compounds. As maximum degradation was achieved in 4 days, prolonged incubation is not suggested. It can be concluded that new strain Bacillus firmus MP04 is the most efficient strain among all the tested strains for DEHP degradation.

Assessment of the awareness about COVID-19 and the following-up of guidelines for biomedical wastes in Jaipur city.

In this COVID-19 era, isolating people and reviewing their contacts has proven to be insufficient to control the COVID-19 pandemic as there was a huge gap between exposure to the virus and isolation due to the late onset of symptoms. This led to the spread of infection and people faced the consequences not only of viral infection, but also of financial and occupational crises. People followed best management practices, however, new variants emerged that caused infection. With little information on new COVID-19 variants and their transmission, the disease spread rapidly in humans. Until now, the link between the spread of COVID-19 and the disposal of biomedical waste with household waste has not been established. Therefore, the only way to prevent infection is to make people aware. It is still necessary to open the doors for research to find the possible cause of the appearance of a new variant of COVID-19. To cope with the situation, the level of awareness among the public and their action towards the prevention of spread of infection caused by COVID-19 and its emerging variants must be known. Therefore, a survey was conducted in Jaipur from January to February 2022 to find out the status of awareness. Results of the survey revealed that both people are aware about the infection caused by COVID-19 and its variants. They are also aware about the precautions to be followed to protect themselves from acquiring COVID-19 infection. Most of the people are using masks but not gloves to prevent themselves from the infection. Merely, 71.6% of young, 100% of adults, 40% of old people sanitize their masks and gloves before disposal. Only 66.5% people are using separate bags for the collection of wastes. Despite of awareness about biomedical waste, 25% of young never sanitize, and 26.13% of young seldom sanitizes their waste before disposal. Such types of cases were not observed in adults and old age groups. Similarly, 2.3% of young did not sanitize PPE kit prior to disposal. Results of this study revealed that there is awareness about the different strains of corona virus and biomedical wastes. However, some people showed casual behaviour in the waste disposal practices. The strict implementation of rules to dispose biomedical waste will be useful for dealing with biomedical waste in this pandemic period.

Adhesive assisted TiB2 coating effects on friction stir welded joints.

Friction stir welding is a novel technique for joining ferrous and non-ferrous materials in a solid state. The groove fill techniques are most popular and generally used by researchers to dope reinforcement in the FSWed zone to improve the properties of joints. The main drawback of this technique is that a few amounts of reinforcement material come out from the groove during the fabrication of the joint. In the present work, the adhesive-assisted reinforcement technique was used to overcome this problem for the fabrication of particulates reinforced friction stirred weld joint. In the present work, the aluminum alloy plate edges were coated with a thin layer of TiB2. The coated and non-coated edge plates were joined using friction stir welding at the rotational speed of 1400 and 2240 rpm, and welding speed of 32 mm/min using a taper threaded pin tool. The tensile strength of coated edge plate welded joints was found highest in comparison to non-coated joints which was 39.74% superior. The percentage elongation of coated edge joint was observed about 1.5 times lower than the non-coated edge plate joint. The flexure strength of TiB2 reinforced coated edge joint was found about 1.5 times higher. However, the impact strength of coated edge plate was found nearly three times lower than the uncoated edge joints. The TiB2 coated edge joints reveal 22.75% higher hardness than the non-coated edge plate joints welded at the rotational speed of 2240.