Effect of an Antioxidant Based on Red Beetroot Extract on the Abiotic Stability of Polylactide and Polycaprolactone

This study investigated the effect of natural antioxidants inherent to beetroot (Beta vulgaris var. Vulgaris) on the ageing of environmentally friendly plastics. Certain properties were examined in this context, comprising thermal, mechanical, and morphological properties. A visual evaluation of relevant changes in the given polymers (polylactide and polycaprolactone) was conducted during an ageing test in a UV chamber (45 °C, 70% humidity) for 720 h. The films were prepared by a casting process, in which samples with the extract of beetroot were additionally incorporated in a common filler (bentonite), this serving as a carrier for the extract. The results showed the effect of the incorporated antioxidant, which was added to stabilize the biodegradable films. Its efficiency during the ageing test in the polymers tended to exceed or be comparable to that of the reference sample.

CORROSION BEHAVIOR STUDY OF STEEL POLE IN DIFFERENT COATING TECHNOLOGY

—Corrosion of steel pole is a serious issue as they used steel pole to support overhead power line in distribution. A lot of money and time are spent for maintenance and repair of existing steel pole. This paper presents investigation on various coating technologies of steel pole for initial corrosion activity. Five types of coating were used on steel samples; epoxy, VEF polyglass, galvanized, epoxy galvanized and polyglass galvanized. The accelerated ageing test, salt spray test and water absorption test were used to determine coating degradation and severity of corrosion process. It was found that, the corrosion rate for epoxy galvanized and VEF polyglass galvanized were higher as the samples were undergoing accelerated ageing test. While VEF polyglass steel showed higher percentage of weight loss during salt spray test. In addition, the results of water absorption behavior showed that epoxy steel gave higher average of absorption rate. The results obtained lead to low degradation of coating as the corrosion rate seem to be uniform

Seed vigour evaluation in petunia seed lots to predict seedling emergence and longevity

This study examined the potential of different vigour tests to reveal differences in performance of nine hybrid petunia seed lots. Saturated salt accelerated ageing test (SSAA) and 48-hour radicle emergence (RE48h) tests were able to predict seedling emergence and longevity potential. The results of accelerated ageing (AA) (at 41/43°C, 48/72 hours, 100% RH), saturated salt accelerated ageing (SSAA) (at 41/43/45°C, 72 hours, 75% RH), mean germination time (MGT), 48-hour radicle emergence (RE48h) and electrical conductivity (EC) tests were compared with seedling emergence in modules and longevity (at 5°C for 24 months and 25°C for 12 months). Initial standard germination (SG) percentages were above 83% in the lots. Seedling emergence ranged between 18 and 89%, germination after storage was between 16 and 88% at 5°C, and 13 and 96% at 25°C. The SSAA test at 43°C and 45°C for 72 hours was correlated with both seedling emergence and longevity. RE48h was correlated with emergence and germination after storage at 5°C for 24 months; MGT and SG was correlated with seedling emergence. Neither AA nor the EC test was correlated with emergence and longevity. Thus vigour, expressed as both emergence and storage potential, was successfully predicted by the SSAA test and RE48h.

Effect of Kerosene on Bituminous Mix

The flexible pavements often do not live up to the designed period due to various reasons, including the addition of petroleum diluents in the bituminous mix. The presence of petroleum diluents in the bituminous mix changes the properties of the bitumen binder as well as the mix. In hot mix plants, kerosene is used as a fuel for heating the aggregate and a little quantity of the kerosene sometimes gets mixed with aggregate in unburned condition. With the presence of petroleum diluents, the bitumen becomes less viscous and the mix becomes softer even after the normal hardening period of the bitumen. This study was conducted to evaluate the property changes in bitumen as well as in mix with the presence of kerosene including Rolling Thin Film Oven (RTFO) short ageing test. A performance study also conducted for the durability of the mix.

Accelerated ageing as a vigour test on chickpea seeds

The objective of this work was to establish the temperature and the period of exposure needed to perform the traditional accelerated ageing test with saturated NaCl salt solution on chickpea seeds. Eight seed lots from two cultivars, including four seeds each, were subjected to germination and vigour tests for initial characterization. Following the methodology of the traditional accelerated ageing test. The seeds were placed on stainless steel screens in boxes with 40 mL deionized water. They were kept at 41 and 45º Celsius for 24 and 48 hours. Furthermore, the accelerated ageing test using [40 g of NaCl in 100 mL of water, thus providing 76% of relative humidity in air] NaCl (salt) solution in place of the deionized water was performed. Aged seeds were sowed in germination paper and kept in a germination chamber at 41º and 45º Celsius. The evaluations were performed five and eight days after sowing. The statistical analysis was performed with a completely randomized design and four replications. The traditional ageing of both cultivars showed a water content higher than the tolerated limits at 48 hour period and 41 and 45 °C. In the saturated saline test, the cultivar BRS Aleppo produced consistent results at temperatures 45 °C for 24 h. The cultivar Cícero showed a low correlation with the initial characterization as the results of accelerated ageing. Thus, for ‘BRS Aleppo’, the recommended accelerated ageing methodology was application of saturated saline solution, when seed exposed to 41 °C for 24 hours with germination evaluation at the first count date. For 'Cicero', satisfactory results were not obtained, and new studies are required to establish a methodology.