Determination of tributyltin through ultrasonic assisted micelle mediated extraction and GFAAS: Application to the monitoring of tributyltin levels in Greek marine species

Ultrasonically assisted extraction into the micelles of both non-ionic and anionic surfactants was applied as a methodology for the isolation of tributyltin (TBT) from fish and mussel tissue prior to determination with graphite furnace atomic absorption spectrometry (GFAAS). The proposed methodology includes extraction of organotin species in the micelles of Triton X-114 or Sodium Dodecane Sulphonic Acid (SDSA), accelerated by the application of ultrasounds. Isolation and subsequent determination of TBT is achieved by ultrasonic assisted back extraction into a water immiscible solvent, utilising the selective partition of TBT from an alkaline environment. Quantitation is performed by GFAAS. Seventy-seven seafood samples including sardines, anchovies and mussels were analysed for tributyltin (TBT) from different coastal regions of northern, eastern and western Greece on the Aegean and the Ionian Sea. Results showed that the shellfish contained a higher amount of TBT than fish (mean value of 0.91 μg/kg for fish and 2.21 μg/kg for mussels). The highest TBT concentration recorded was 19.50 μg/kg for sardines in N. Mihaniona and 14.27 μg/kg for mussels in Fthiotida. TBT concentrations found in the present study were much lower than those reported in the literature regarding Greece and other countries.     

Effect of insulation layer for thermal shock in cryogenic composite laminates

The structural weight of a cryogenic propellant tank for reusable launch vehicles (RLVs) can be effectively reduced by the use of advanced composite materials. However, microscopic damage such as transverse matrix cracks (TMC) and delaminations are prone to develop in composites well below the load levels that would result in mechanical failure. This microscopic damage leads to a leakage path for the fuel. The leakage is influenced by many factors including connectivity of the cracks, residual and service‐induced stresses, and composite stacking sequence. This article is concerned with the effect of thermal gradients due to sudden exposure to a cryogenic temperature with and without insulation layer. An investigation of the insulation layer for sudden exposure to cryogenic temperatures is conducted numerically. The exposure of the harsh environment could make the damages such as delaminations, TMC, and leakage path. The defects from manufacturing could be formed, and they are critical parts under sudden exposure to cryogenic temperature. Therefore, the qualitative analysis for insulation technique is needed. The results from this article are very important because the stress levels which cause damages can be predicted and also controlled using the insulating techniques. The insulation skill which can suppress the stress levels is newly introduced in this article for RLV cryogenic fuel tank. Moreover, the effect of lay‐ups is also investigated in this article. The thermal gradient can be controlled by using different lay‐ups. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers     

Flexmi: a generic and modular textual syntax for domain-specific modelling

Software and Systems Modeling - Domain-specific languages allow engineers and domain experts to express problems and design solutions using domain-focused vocabularies and abstractions, by means of...     

Correction to: The effect of cognitive workload on decision authority assignment in human–robot collaboration

Cognition, Technology & Work -     

Correction to: A decentralized honeypot for IoT Protocols based on Android devices

International Journal of Information Security -     

The effect of cognitive workload on decision authority assignment in human–robot collaboration

Cognition, Technology & Work - Human–robot collaboration in dynamic industrial environments warrants robot flexibility and shifting between tasks. Adaptive robot behavior unavoidably...