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The ability of the agricultural residue of Phragmites australis to serve as an absorbent material used to remove phenol from aqueous solutions in batch and continuous fixed-bed columns was investigated. Prepared adsorbents were characterized by SEM, FTIR, and pHpzc methods. The equilibrium adsorption (qe) of phenol was increased from 9.61 to 29.40 mg/g when the initial phenol concentrations increased from 50 to 150 mg/L. The max adsorption capacity of Phragmites australis was found to be 29.60 mg/g at 30 °C. In column studies, a higher flow rate, higher initial concentration of phenol, and shorter packing layer height increase the column adsorption capacity of phenol. In a batch and continuous fixed-bed column studies, the experiment data was evaluated by some classic models. Fitting degree between the experimental results shows that the pseudo-second-order adsorption kinetics and Langmuir model were the best. Thomas and Yoon-Nelson models were in good agreement with the experimental breakthrough curve data. Both batch and continuous investigation indicated that Phragmites australis could be used as a fine adsorbent to remove phenol and that the adsorption efficiency improved significantly in the column experiment. [ABSTRACT FROM AUTHOR]

Mnium cuspidatum Hedw. from the Bashuigou landscape of the Guandi Mountains, Shanxi Province, China, found to be associated with a cyanobacterium that was successfully isolated and cultivated under axenic conditions and designated as Microcoleus sp. GD based on its morphology. Phylogenetic analysis of 16S rRNA alone and of the 16S rRNA combined with the 16S-23S internal transcribed spacer (ITS) region, and the presence of an 11-bp insert in the 16S rRNA gene, indicated that Microcoleus sp. GD was as Microcoleus vaginatus. Phylogenetic analysis of the 16S rRNA gene sequences revealed that Microcoleus sp. GD formed a well-supported clade with aquatic epipelic strains of M. vaginatus from the Czech Republic and with desert strains from the USA. Microcoleus sp. GD was more closely related to the aquatic strains living at the seciment/water interface. The secondary structure of the 16S-23S ITS showed that the Box-B helix of Microcoleus sp. GD was structurally was similar to these strains but quite different from the desert strains. Furthermore, the D1-D1′ helices of all strains varied but Microcoleus sp. GD was again most similar to the aquatic strains. [ABSTRACT FROM AUTHOR]

In recent years, examinations based on morphological characters and phylogenetic analyses have begun to reveal the diversity of photobionts in lichen symbioses. However, still little is known regarding genetic diversity and ecological adaptation of algal partners in lichen symbioses. In this study, we investigated the photobiont Chlorella 'sp. GC' (Trebouxiophyceae), a partner of Porpidia crustulata from the Guancen Mountains, China. We examined the relationship between photobiont layer thickness and Porpidia crustulata growth over a 6-year period (2007-2012). Although Porpidia crustulata exhibited moderate growth rates (0.4-0.62 mm year), photobiont layer became increasingly thinner over the six-year period. We speculate that prolonged exposure to sunlight and desiccation may deleteriously alter photobiont morphology and physiology. Porpidia crustulata may be forced into a state of physiological dormancy. [ABSTRACT FROM AUTHOR]

The algal photobiont of the lichen Porpidia crustulata from the Guancen Mountains was successfully cultivated under axenic conditions and tentatively designated as Chlorella sp. GC. The phylogenetic analysis of ribulose bisphosphate carboxylase ( rbcL) and internal transcribed spacer (ITS) nucleotide sequence data revealed that this alga is closely related to C. sorokiniana. There are clear morphological differences between Chlorella sp . GC associated with Porpidia crustulata and the free-living C. sorokiniana, the former having a larger central pyrenoid. Based on our genetic and morphological characterization, the Chlorella photobiont of Porpidia crustulata is distinct from closely related Chlorella species. [ABSTRACT FROM AUTHOR]