Soils excavated in construction works often contain non-anthropogenic heavy metals and metalloids due to their geologic histories. Evaluation of their leaching behaviors is essential to predict the ...environmental impact and achieve an optimum design when reusing such soils as construction materials. However, applicability of the conventional column leaching test to soils containing non-anthropogenic substances is uncertain, since their chemical forms and leaching processes are different from those in contaminated soils. Also, the column size is one of factors influential to the leaching behavior. This paper addresses the leaching behaviors of arsenic (As) and other inorganic constituents contained in a marine sediment by employing two different-size column percolation tests (50 mm in diameter × 300 mm in height and 150 mm in diameter × 700 mm in height) with saturated/unsaturated flow conditions. Long term leaching profiles were analyzed to assess the effects of specimen size and flow conditions. At the middle of the unsaturated larger column, higher As leaching concentrations were observed under neutral condition. However, As leaching was limited at the bottom due to precipitation of As with co-precipitation of iron and aluminum compounds. As a result, there was no significant difference in both As leaching amount and leaching processes obtained in two column percolation tests.
Two Fatal Cases of Caffeine Poisoning JERIN, Sultana Jannatul Ferdoush; KIMURA-KATAOKA, Kaori; FUJIHARA, Junko ...
Shimane Journal of Medical Science,
09/2020, Volume:
37, Issue:
3
Journal Article
Peer reviewed
Open access
A caffeine overdose is most likely to result from the consumption of nutritional supplements or caffeine pills. Herein, we describe two fatal cases of caffeine intoxication. Case 1: A Japanese man in ...his 30s was found dead, with two bottles of water and unopened tablets for motion sickness near his body. Caffeine concentrations were 99.6 μg / mL in the cardiac blood and 169.1 μg / mL in stomach contents. Case 2: A Japanese man in his 40s was found dead, with an empty bottle of caffeine and six empty boxes of Travelmin (a motion sickness medication) in a trash can. Caffeine concentrations were 79.6 µg / mL in the cardiac blood and 876 µg / mL in the stomach contents. Fatal caffeine poisoning is comparatively uncommon, but it has recently been increasing due to the easy availability. For the prevention of caffeine overdoses, there should be heightened public awareness of the potential dangers of a caffeine overdose.
This study aims to reveal the ultrasonic spot welding behavior of carbon fiber reinforced thermoplastics (CFRTP) using polymer based energy director. The materials used for spot welding are ...woven-CF/PPS laminates and energy director consisting of PPS polymer. The ultrasonic oscillator for the ultrasonic spot welding process has an oscillation frequency of 40 kHz and a maximum output of 600 W. The welding load and displacement of ultrasonic horn during welding process were precisely controlled by using an electric servo press machine. The effects of welding load and thickness of energy director on ultrasonic welding behavior and joining strength were investigated to reveal the welding behaviour. The temperature of the joining part during ultrasonic welding was measured by a ultrafine thermocouples, and the welding load and displacement of the horn was measured by the servo press machine. The welding part was evaluated by microscopic observation and cross-sectional observation using microscope and SEM. From the experimental results, it was revealed that the thickness of the energy director was significantly affects the ultrasonic welding behavior. From the result of single lap tensile shear test, it was found that the there was proper thickness of energy director to increase the joining strength.
PDF
