Xinyu Ni,Xuyan Li,Guojing Ran,Jiali Chen,Xinwei Jiang,Jianxia Sun,Weibin Bai
This study aimed to determine whether Trachinotus ovatus and Pampus argenteus could be differentiated by multi-element composition or stable isotope ratio analysis of δ 13 C and δ 15 N. The multi-element analysis values of a total of 60 Pampus argenteus samples from three sites and 60 Trachinotus ovatus samples from four sites around China were determined, and the other 60 samples of Pampus argenteus and 51 samples of Trachinotus ovatus were tested by principal component analysis (PCA) to estimate the accuracy of origin identification. The results showed that the cross-validation accuracy rate is 92.2% for the Pampus argenteus and 98.3% for the Trachinotus ovatus . Stable isotope analysis of δ 13 C and δ 15 N also can distinguish Trachinotus ovatus from different geographical origins. These results showed that the usefulness of multi-element and stable isotope analysis as indicators for authenticating the geographical origin of two pomfrets in China.
The rapid development of ocean exploration and underwater robot technology has put forward new requirements for underwater sensing methods, which can be used for hydrodynamic characteristics perception, underwater target tracking, and even underwater cluster communication. Here, inspired by the specialized undulated surface structure of the seal whisker and its ability to suppress vortex-induced vibration, a multidirectional hydrodynamic sensor based on biomimetic whisker array structure and magnetic 3D self-decoupling theory is introduced. The magnetic-based sensing method enables wireless connectivity between the magnetic functional structures and electronics, simplifying device design and endowing complete watertightness. The 3D self-decoupling capability enables the sensor, like a seal or other organisms, to perceive arbitrary whisker motions caused by the action of water flow without complex calibration and additional sensing units. The whisker sensor is capable of detecting a variety of hydrodynamic information, including the velocity (RMSE < 0.061 m s −1 ) and direction of the steady flow field, the frequency (error < 0.05 Hz) of the dynamic vortex wake, and the orientation (error < 7°) of the vortex wake source, demonstrating its extensive potential for underwater environmental perception and communication, especially in deep sea conditions.
Copolymerization of methyl methacrylate (MMA) and acrylate terminated poly(ethylene oxide- co -ethylene carbonate) (PEOC) macromonomer yields graft copolymer with PEOC side chains. By use of quartz crystal microbalance with dissipation (QCM-D), we have investigated the adsorption of proteins on the surface constructed by the copolymer in seawater. It shows the polymeric surface exhibits protein resistance depending on the content of the side chains. Marine field tests show the protein resistant surface can effectively inhibit marine biofouling for more than 12 weeks.
危险品化学品经营许可证（带存储）