The maximum methane storage capacity (MSC) is of critical importance of methane hydrate to store methane. This paper reports the effects of vesicle solutions, formed through combination of carboxylate surfactants with cationic quaternary ammonium salt including hydroxypropyl trimethyl ammonium chloride chitosan (HACC) or dodecyl trimethyl ammonium chloride (DTAC), on the formation of methane hydrate. It was found that vesicles could raise the maximum MSC of hydrate by about 10 (V/V, the volume of methane stored by one volume of hydrate) at appropriate anion and cation concentrations. For example, at 800 ppm (parts per million) of sodium laurate (SL) and 600 ppm of HACC concentrations, the formed vesicles could elevate the maximum capacity to 151 V/V, 5.3% higher than that of sodium laurate alone. The vesicles formed could increase the maximum MSC, from 136 V/V to 147 V/V by sodium oleate (SO) and HACC, 145 V/V to 153 V/V by sodium decanoate (SD) and HACC and 137 V/V to 149 V/V by SO and DTAC. The reason for the enhancement is that the large hydrophobic space of the vesicles could solubilize methane molecules and facilitate them to contact with water molecules.
Linawati Sutrisno,Yan Hu,Xinkun Shen,Menghuan Li,Zhong Luo,Liangliang Dai,Sixiang Wang,Julia Li Zhong,Kaiyong Cai
Infection associated with orthopedic implants is the chief cause of implant failure. An important consideration to prevent the infection at implants is to inhibit the biofilm formation for the initial 6 h. Therefore, we fabricated hyaluronidase-sensitive multilayers of chitosan (Chi)/sodium hyaluronate-lauric acid (SL) onto the surface of bone morphogenetic protein 2 (BMP2) loaded titanium nanotube (TNT) via spin-assisted layer-by-layer technique. The results of both Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance ( 1 H NMR) confirmed the successful synthesis of SL. The multilayer structure on BMP2 loaded TNT was characterized by field-emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and water contact angle, respectively. The release profiles confirmed that hyaluronidase could trigger the release of lauric acid (LA) from the SL multilayer and accelerate the release of BMP2 in the system. The hyaluronidase-sensitive-multilayer-coated BMP2-loaded TNT (TNT/BMP2/(Chi/SL/Chi/Gel) 4 ) not only demonstrated good antibacterial capability, but also showed good biocompatibility in in vitro usage, which was supported by the efficient growth inhibition of both Staphylococcus aureus and Escherichia coli , as well as higher cell viability, alkaline phosphatase activity, mineralization capability, and higher gene expression of osteoblasts on TNT/BMP2/(Chi/SL/Chi/Gel) 4 . This study developed an alternative approach to fabricate effective antibacterial implants for orthopedic implantation.
危险品化学品经营许可证（带存储）