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The hydrophobicity of ultrafiltration membranes is the main cause of membrane fouling and reduced permeability, so it is necessary to improve the hydrophilicity and anti-fouling performance of ultrafiltration membrane materials. MoS2 nanoparticles that were modified with polydopamine (PDA) and polyethyleneimine (PEI), named MoS2-PDA-PEI, were added to fabricate a polyethersulfone ultrafiltration membrane (PES/MoS2-PDA-PEI) for the first time. The effects of modified MoS2 nanoparticles on membrane performance were clarified. The results indicated that the permeability, rejection, and anti-fouling capability of the hybrid PES/MoS2-PDA-PEI membrane have been improved compared with the pristine PES membrane. When the content of MoS2-PDA-PEI nanoparticles in the membrane is 0.5%, the pure water flux of the hybrid membrane reaches 364.03 L m−2 h−1, and the rejection rate of bovine serum albumin (BSA) and humic acid (HA) is 96.5% and 93.2% respectively. The flux recovery rate of HA reached 97.06%. As expected, the addition of MoS2-PDA-PEI nanoparticles promotes the formation of the porous structure and improves the hydrophilicity of the membrane, thereby improving its antifouling performance.

This paper has made an active attempt on recovering water from flue gas using membranes. The properties of SPEEK/PES, a hydrophilic composite hollow fiber membrane, are studied in the present paper using experimental analyses of thermal gravimetric, differential scanning calorimetry and scanning electron micrograph. Experimental results show that SPEEK/PES composite hollow fiber membranes have excellent thermal stability and mechanical properties in flue gas. An experiment with using simulated flue gas (N2/water vapor mixed) is carried out to study the impact of sweep gas flow rate and feed gas temperature on the membrane module properties. The results indicate that the water recovery rate increases with the temperature increasing from 40 °C to 70 °C. The application of capturing the water in flue gas is very attractive, and it will provide a new way of saving energy and alleviating the haze.

New disulfide linked [4]carceplex 54»guests was synthesized. This kind of carceplex has diastereotopic protons that can be used in the study of "twistomers" of the carceplex. The twisting process was studied by variable temperature NMR spectroscopy. The activation energy barrier AG* of the twisting on 54 depends on the size of guest molecules. The smaller the guest molecule, the higher the AG* is. We proposed an explanation for the observation. The location of guests inside the host molecule was also studied. The reversibility of disulfide bond formation in this series of compounds and the self-assembly during the formation of carceplexes suggest 54 and the previously synthesized 32 are excellent candidates for the study of the first dynamic combinatorial libraries of carceplexes. Using the disulfide linked [4]carceplexes 54 and disulfide linked [5]carceplexes 32, we worked out reversible conditions to synthesize the corresponding carceplexes from dynamic combinatorial libraries. The yield of disulfide linked [5]carceplexes is improved significantly from 14% (kinetic condition) to 50% (thermodynamic condition). The result on disulfide linked [4]carceplexes is not as good as on disulfide linked [5]carceplexes. We believe the reason is that we haven't found a good template for the disulfide [4]carceplex. Guest exchange was also observed in the library, which confirmed that this library is dynamic. The preparation of [5]cavitand benzylthiol 31 was modified. Using the modified reaction condition, 31 can be synthesized in 40% yield from [5]cavitand, which is much higher than the yield with old reaction condions (10%). This improvement made 32 a more useful template in the study of DCLs. During the synthesis of disulfide linked [4]carceplexes, we synthesized a hemicarcerand, 58, with new trithiacarbonate linkers in very high yield (80%). An X-ray crystal structure was obtained. Based on template studies, we propose the template for the self-assembly of this hemicarcerand can be an inorganic salt, an unprecedented template for such a system.