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Lifeboat is one of the most important life-saving equipment for escaping at sea when a ship is abandoned in an extreme emergency. An accurate drift model can help rescuers find the drift position of lifeboat in the shortest time, thus improving the efficiency of marine search and rescue (SAR) at sea and ensuring the safety of wrecked people. The purpose of this paper is to investigate the drift characteristics and to develop an accurate drift prediction model for the open lifeboat. First, large-scale drift experiments were conducted to analyze the drift characteristics with three 6.5-meter-long real-size open lifeboats in the South China Sea. Next, three drift prediction models of the lifeboats were developed using the least squares method based on the drift experimental data. Finally, the drift prediction models of the lifeboats were compared and evaluated using the Lagrangian method and Monte Carlo technique, respectively. Results indicate that the probability of positive crosswind leeway (CWL) of the open lifeboat is 47.5%. The jibing frequency is 6% per hour, and the maximum leeway divergence angle is 45°. These drift characteristics are very important for the prediction of the open lifeboat drift trajectory. The comparison results of three drift models show that the improved drift model is more accurate than the other two drift models for predicting drift trajectories of the open lifeboat, which can be directly applied to maritime search and rescue operations in the South China Sea.

Four nanoporous carbons have been synthesized by using similar silica template method. The structural characterizations showed that the carbons retained ordered hexagonal or cubic pore structure expect for disordered CS41, which was prepared using MCM-41 as template. Nitrogen adsorptions at 77 K revealed that carbons with different pore size distribution, specific surface area and pore volume were obtained. The hydrogen adsorption capacity was measured by volumetric method, and the most promising candidate resulted to be microporous carbon CS41, which exhibited the highest H2uptake of 1.17 wt % at 77 K and 1 bar. The capacities of hydrogen adsorbed in the nanoporous carbons were correlated with specific surface area and microporous volume. The result demonstrated that the H2uptake in the carbons had essential relationship with volume of pores smaller than 1 nm.

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