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China’s 7000 m manned submersible JIAOLONG carried out an exploration cruise at the Mariana Trench from June to July 2016. The submersible completed nine manned dives on the north and south area of the Mariana Trench from the depth of 5500 to 6700 m, to investigate the geological, biological and chemical characteristics in the hadal area. During the cruise, JIAOLONG deployed a gas-tight serial sampler to collect the water near the sea bottom regularly. Five days later, the sub located the sampler in another dive and retrieved it successfully from the same location, which is the first time that scientists and engineers finished the high accuracy in-situ deployment and retrieval using a manned submersible with Ultra-Short Base Line (USBL) positioning system at the depth more than 6600 m. In this task, we used not only the USBL system of the manned submersible but also a compound strategy, including five position marks, the sea floor terrain, the depth contour, and the heading of the sub. This paper introduces the compound strategy of the target deployment and retrieval with the practical diving experience of JIAOLONG, and provides a promising technique for other underwater vehicles such as manned submersible or Remote Operated Vehicle (ROV) under similar conditions.

Research status of state monitoring technology for air compressor and existing problems were analyzed, meanwhile, the necessity of designing a remote monitoring system was discussed in the paper. On the basis of analyzing the air compressor’s working principle, a remote monitoring system for air compressors was constructed by King-view configuration software, according to the technology of Ethernet and computer communication. With this system, real-time remote monitoring of compressors’ state and related operation parameters was realized; in addition, the latent faults of compressors on working could be predicted and warned. And that the efficiency of air compressors is improved, and the accidents of air compressors are avoided efficiently.

Two conformationally constrained templates have been designed to provide selective inhibitors of the coagulation cascade serine protease, Factor Xa (FXa). The most active inhibitor, 2,7-bis[( Z )- p -amidinobenzylidene)]-3,3,6,6-tetramethylcycloheptanone, exhibits a K i of 42 nM against FXa, with strong selectivity against thrombin (1000-fold), trypsin (300-fold) and plasmin (900-fold). With only two freely rotatable bonds, molecular modeling suggests that one amidine group is positioned into the S1 pocket, forming hydrogen bonds with the side chain of Asp189, similar to other amidine-based inhibitors, with the second benzamidine positioned into the S4 pocket in a position to form strong cation–pi bonding with the S4 aryl cage. We suggest that this interaction plays an important role in the specificity of these inhibitors against other serine proteases.