RESUMO
Ultraviolet radiation, oxidation, temperature, moisture, and traffic loads produce degradation and brittleness in the asphalt pavement. Microcracks develop into macrocracks, which eventually lead to pavement failure. Although asphalt has an inherent capacity for self-healing, it is constricted. As a result, damages build beyond the ability of asphalt to repair themselves. This research employs the in-situ crack healing method of encapsulated rejuvenator technology to enhance the insufficient self-healing capability of roads. This allows the extrinsically induced healing in asphalt to assist it in recovering from damage sustained during service life. Optical microscopy, thermogravimetric analysis, and the compressive load test of capsules were done to characterise their properties. We measured the self-healing behaviour of encapsulated rejuvenator-induced asphalt utilising the three-point bending beam tests on unaged, short-term aged and long-term aged asphalt beams. The rate of oil release before and after healing was quantified using Fourier transform infrared spectroscopy. The results of these tests were utilised to explain the link between healing time, temperature, asphalt ageing, and healing level. Overall, it was determined that the encapsulated rejuvenator was acceptable for mending asphalt mixes because it increased healing temperature and duration, resulting in an up to 80% healing index.
RESUMO
OBJECTIVE: Phosphorous is an essential micronutrient of plants and involved in critical biological functions. In nature, phosphorous is mostly present in immobilized inorganic mineral and in the fixed organic form including phytic acid and phosphoesteric compounds. However, the bioavailability of bound phosphorous could be enhanced by the use of phosphate solubilizing microorganisms such as bacteria and fungi. The phytases are widespread in an environment and have been isolated from different sources comprising bacteria and fungi. METHODOLOGY: In current studies, we show the successful use of gamma rays and EMS (Ethyl Methane Sulphonate) mutagenesis for enhanced activity of phytases in a fungal strain Sporotrichum thermophile. RESULTS: We report an improved strain ST2 that could produce a clear halo zone around the colony, up to 24â¯mm. The maximum enzymatic activity was found of 382â¯U/mL on pH 5.5. However, the phytase activity was improved to 387â¯U/ml at 45⯰C. We also report that the mutants produced through EMS showed the greater potential for phytase production. CONCLUSION: The current study highlights the potential of EMS mutagenesis for strain improvement over physical mutagens.