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Polycyclic aromatic hydrocarbons (PAHs) are pollutants that have attracted great attention in recent years regarding the issue of atmospheric pollution. Being harmful to human health, PAHs also promote the growth of secondary particles. Consequently, several countries have begun to control the emission of PAHs in exhaust gases with different techniques, which is a hot topic in the atmospheric environment field. Adsorption is one of the most significant methods and has been accepted by industries, of which the adsorbent properties are key factors. Researchers have studied the adsorption equilibrium, kinetics, and desorption properties of PAHs as special low-volatile gases on conventional activated carbons and novel mesoporous adsorbents. They have also examined the optimal balance between adsorption and desorption based on the corresponding adsorbents. In this paper, these results and related applications are reviewed, and the advantages of mesoporous adsorbents over traditional adsorbents on purifying PAHs are specifically analyzed. This work can be a reference for future studies on the adsorption purification of PAHs and other low-volatile gases.

Objective: To investigate the changes of adhesion molecules, cyclic adenosine monophosphate(cAMP) and cyclic guanosine monophosphate (cGMP) in divers post 480 heliox saturation diving., Methods: Four divers were compressed within 96 hours to depths of 480 m with heliox-oxygen and held at the designated depth for 49 hours, excursion to 493 m during their saturation stay, then decompressed within 302 hours to the surface. The blood samples were collected before compression and post decompression, the expression level of intercellular adhesion molecule-1(ICAM-1), E-selectin, P-selectin, cAMP, cGMP were detected with ELISA analysis box., Results: Compared with the levels of CAMs before compression, the levels of ICAM-1, E-selectin, P-selectin and cGMP in the serum were changed post decompression (P > 0.05). The levels of cAMP were significantly elevated post decompression (629.91 +/- 75.01) nmol/L vs (66.72 +/- 83.15) (P < 0.05)., Conclusion: The decompression schedule in this heliox saturation diving is safe, the decompression sickness pathology in this diving has not been induced. But the stress response of divers are enhanced by this great depth saturation diving.

Objective: To investigate the change of adhesion molecules in the lungs of rats suffered with decompression sickness (DCS)., Methods: Male SD rats were placed in the hyperbaric chamber, the chamber was compressed within 3 minutes to depths of 7 absolute atmosphere (ATA) and held at the designated depth for 60 min, then rapidly decompressed (3 min) to the surface. Rats were observed for signs of DCS after decompression. The brains, hepatis, and lungs were removed at 30 min, 6 h, 24 h post decompression, fixed and stained with hematoxylin eosin for routine histologic analysis. Lung paraffin sections were immunostained for the expression of intercellular adhesion molecule-1 (ICAM-1), E-selectin and major histocompatibility complex class II molecule (MHC-II). 2% evans blue dye in normal saline was injected 30 minutes prior to 6 h, 24 h before decompression. After 30 min, animals were perfused with 0.9% normal saline and lungs were harvested. Evans blue in the plasma was quantified by wavelength spectrophotometric analysis at 620 nm., Results: Results showed that there were hemorrhage and edema changes in the lungs, liver and brain at 30 min post decompression. Compared with control animals maintained at 1 ATA, the levels of E-selectin, ICAM-1 and MHC-II in the lungs of DCS rats were significantly increased post decompression. Compared with control animals, evans blue in the plasma was much higher at 6 h, 24 h post decompression., Conclusion: The bubble-induced adhesion molecule-mediated endothelial activation may be involved in the pathogenesis of DCS.