Design and Synthesis of Amphiphilic Catalyst [C16mim]5VW12O40Br and Its Application in Deep Desulfurization with Superior Cyclability at Room Temperature

Achieving long-term stable deep desulfurization at room temperature and recovering high value-added sulfone products is a challenge at present. Herein, a series of catalysts [C_nmim]₅VW₁₂O₄₀Br (C_nVW₁₂, 1-alkyl-3-methylimidazolium bromide tungstovanadate, n = 4, 8, 16) were presented for the room temperature catalytic oxidation of dibenzothiophene (DBT) and its derivatives. Factors affecting the reaction process, such as the amount of catalyst, oxidant, and temperature, were systematically discussed. C₁₆VW₁₂ showed higher catalytic performance, and 100% conversion and selectivity could be achieved in 50 min with only 10 mg. The mechanism study showed that the hydroxyl radical was the active radical in the reaction. Benefiting from the "polarity strategy", the sulfone product accumulated after 23 cycles in a C₁₆VW₁₂ system, and the yield and purity were about 84% and 100%, respectively.

Construction of Water-Stable Rare-Earth Organic Frameworks with Ambient High Proton Conductivity Based on Zirconium Sandwiched Heteropolytungstate

Water-stable proton-conducting materials owning excellent performances at ambient temperatures are currently one of the crucial challenges. Herein, four water-stable three-dimensional polyoxometalate-based rare-earth organic frameworks have been successfully synthesized and formulated as H{Ln₄(L)₂(H₂O)₂₁[Zr₃(OH)₃(PW₉O₃₄)₂]}·15H₂O (1-3) (Ln = La (1), Ce (2), Pr (3); L = 3,5-pyridine dicarboxylic acid), which are the first examples of MOFs constructed by a zirconium sandwiched polyoxoanion. There are abundant coordinated water molecules functionalizing the Pr^III centers, and simultaneously, plenty of lattice water molecules are fitted into the channel of the framework. A continuous H-bonding network is found between the architectures and plays an important role in stabilizing the structure. Benefiting from the consecutive H-bonding networks, compounds 1-3 showed high proton conductivities at ambient temperature (up to 1.05 × 10^-3 S·cm^-1 under 98% RH) by a synergistic effect of the combined components.

Crystal structure and electrochemistry properties of one two-dimensional heteropolyoxoniobate based on four- and five-vanadium-capped Keggin anions

One two-dimensional heteropolyoxoniobate compound H9[Cu(H4dap)2(H2O)]8{K[Cu(H3dap)2]4}2[VNb12O40(VO)4]3[VNb12O40(VO)4(VO)]·48H2O (1) (H4dap = 1,2-diaminopropane) was obtained by a hydrothermal method.

[Different viral doses of cytomegalovirus infection in the left and right colons]

Objective: To compare the differences in the detection rates of cytomegalovirus (CMV) infection between the left and right colons for guiding endoscopic biopsy-sites. Methods: The cases of colonic CMV infection confirmed by histology at the Peking Union Medical College Hospital from July 2015 to July 2018 were collected and analyzed. Splenic curvature was used as the dividing point between the left and right colons. The CMV inclusions were identified histologically, and the CMV infected cells were detected using immunohistochemistry (EnVision method). The numbers of infected cells in the left and right colons were compared by histological and immunohistochemical results. A total of 731 patients were identified. Ten of the 731 patients had histological specimens of both left and right colons and were confirmed with CMV EnVision immunohistochemical study. There were 25 biopsy or resection specimens. Seven patients were male and 3 were female, and their ages ranged from 29 to 66 years, with a median age of 55 years. All of the 10 patients were also diagnosed with ulcerative colitis. Results: The number of the cells infected with CMV in the left colon was 115 (1-41), while that in the right colon was 76 (0-51). In 8/10 cases, the number of CMV infected cells in the left colon was more than that in the right colon. Conclusions: The study on the biopsies and resection specimens suggests that CMV infection is mostly present in the left colon. The left colon thus might be an important endoscopic biopsy-site for the cases with suspicion of CMV infection.