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Halophytes are valuable salt-, alkali- and drought-resistant germplasm resources. However, the characteristics of mineral elements in halophytes have not been investigated as intensively as those in crops. This study attempted to investigate the characteristics of mineral elements for annual halophytes during their growth period to reveal their possible physiological mechanisms of salt resistance. By using three native annual halophytes (Salsola subcrassa, Suaeda acuminateand Petrosimonia sibirica) distributed in the desert in Northern Xinjiang of China, the dynamic changes in the mineral element contents of annual halophytes were analyzed through field sampling and laboratory analyses. The results demonstrated that the annual halophytes were able to absorb water and mineral nutrients selectively. In the interaction between the annual halophytes and saline soil, the adaptability of the annual halophytes was manifested as the accumulation of S, Na and Cl during the growth period and maintenance of water and salt balance in the plant, thus ensuring their selective absorption of N, P, K, Ca, Mg and other mineral nutrients according to their growth demand. By utilizing this property, halophyte planting and mowing (before the wilting and death periods) could bioremediate heavy saline-alkali soil.

The bioavailability and biodegradation of polycyclic aromatic hydrocarbons (PAHs) can be increased through the addition of surfactants. Previous studies of this nature have been conducted under mesophilic conditions. Hence, the aim of the present study was to investigate the effects of synthetic surfactants and biosurfactants on solubilization and degradation of phenanthrene (PHE) in a series of batch solution experiments under thermophilic conditions. Tween 80, Triton X‐100, and biosurfactants produced from Pseudomonas aeruginosastrain P‐CG3 (P‐CG3) and Pseudomonas aeruginosaATCC 9027 (P. 9027) were used in this study. Surfactants effectively enhanced the solubility of PHE at 50°C and the biosurfactant from P‐CG3 was most effective with a 28‐fold increase in apparent solubility of PHE at a concentration of 10 × critical micelle concentration (CMC) compared with the controls. However, addition of synthetic surfactants or biosurfactants inhibited the biodegradation of PHE in mineral salts medium by an isolate Bacillussp. B‐UM. Degradation of PHE diminished with increasing surfactant concentrations, and PHE degradation was completely inhibited for all the surfactants tested when the concentrations were greater than their respective CMC. The growth test suggested that Tween 80 and biosurfactants were degradable, but preferential utilization of these surfactants as substrates was not the mechanism for explaining the inhibition of PHE biodegradation. Because of the hydrophobic property of B‐UM, degradation inhibition of PHE by surfactants was probably due to the reduction of direct contact between bacterial cells and PHE.

The epitaxial growth of single-crystal thin films relies on the availability of a single-crystal substrate and a strong interaction between epilayer and substrate. Previous studies have reported the roles of the substrate (e.g., symmetry and lattice constant) in determining the orientations of chemical vapor deposition (CVD)-grown graphene, and Cu(111) is considered as the most promising substrate for epitaxial growth of graphene single crystals. However, the roles of gas-phase reactants and graphene–substrate interaction in determining the graphene orientation are still unclear. Here, we find that trace amounts of oxygen is capable of enhancing the interaction between graphene edges and Cu(111) substrate and, therefore, eliminating the misoriented graphene domains in the nucleation stage. A modified anomalous grain growth method is developed to improve the size of the as-obtained Cu(111) single crystal, relying on strongly textured polycrystalline Cu foils. The batch-to-batch production of A3-size (∼0.42 × 0.3 m2) single-crystal graphene films is achieved on Cu(111) foils relying on a self-designed pilot-scale CVD system. The as-grown graphene exhibits ultrahigh carrier mobilities of 68 000 cm2V–1s–1at room temperature and 210 000 cm2V–1s–1at 2.2 K. The findings and strategies provided in our work would accelerate the mass production of high-quality misorientation-free graphene films.