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One new Metal-Organic Frameworks, [Co4O(L)2]·(DMF)8·(H2O)8 (1, H3L = 4-[N,N-bis(4-methylbenzoic acid)amino]benzoic acid), had been successfully constructed under hydrothermal conditions, which firstly presents the [Co4O(COO)6] secondary-building unit similar to the typical [Zn4O(COO)6] one via single-crystal X-ray diffraction studies. All of the cobalt ions exhibit the four-coordinate environment, and possess more open metal sites. Heterogeneous catalytic experiments on allylic oxidation of cyclohexene indicate that 1 exhibits high catalytic activity by utilizing the tert-butylhydroperoxide (t-BuOOH) as the oxidant. The activation energy for the whole process of oxidation of cylcohexene had been calculated as 40.6 kJ mol−1, which indicate the important role of the special [Co4O(COO)6] cluster in the resulted heterogeneous catalyst.

Three new Metal-Organic Frameworks, Zn(L1)(H2O)·NMP (1), [Zn4O(L2)(NMP)(H2O)]·(NMP)2 and [Zn2(OH)(L3)(NMP)(H2O)]·NMP (3) (H2L1 = 1,4-Naphthalate, H2L2 = iso-Phthalic acid, H3L3 = 1,3,5-Benzenetricarboxylic acid), have been successfully constructed under the same reaction conditions. Although these ligands have been widely utilized for the construction of versatile MOFs by adjusting the reaction conditions, rare samples had been fabricated via the utilization of N-Methyl pyrrolidone (NMP). Different to the previous reported MOFs, the diversities of the title structures should be caused by the choice of pure solvent N-Methyl pyrrolidone and the configurations of the selected linkers. Guided by the synergistic effect between metal ions, the configuration of linkers and NMP, the different metal secondary building units (SBUs), porous structures and topological structures have been formed in these MOFs. In addition, all of these activated samples for these MOFs could reserve certain porosities and exhibit the corresponding gas adsorption for CO2 and H2.

Two new Metal-Organic Frameworks, [Zn3(tdc)3(H2O)2]·2.5(dioxane) (1) and [Mn3(H2O)3(tdc)3(dioxane)]·2(dioxane) (2), have been successfully constructed by the utilization of 2,5-thiophenedicarboxylate ligand (H2L) and Zn/Mn ions. Although trinuclear metal secondary building units (SBUs) have been stabilized in these two final frameworks, the different connection modes are exhibited due to the difference of coordination habits of metal ions. The trinuclear [Zn3(COO)6] SBU exhibits the 6-connected mode via six L ligands, whilst the trinuclear [Mn3(COO)6] SBU presents the 8-connected mode via six L ligands and two p-dioxane molecules. The different connection modes of two trinuclear SBUs lead to the formation of distinct topological structures (6-connected pcu for 1; 8-connected tsi for 2). Both of the activated samples for these two MOFs could reserve the certain porosities and exhibit the corresponding gas sorption for H2.

Developing an effective method to improve the quality of Pu-erh tea is of great scientific and commercial interest. In this work, Penicillium chrysogenum P1 isolated from Pu-erh tea was inoculated in sterilized or unsterilized sun-dreid green tea leaves to develop pure-culture fermentation (PF) and enhanced fermentation (EF) of Pu-erh tea. Spectrophotometry and high performance liquid chromatography determined that contents of free amino acids (FAA), total tea polyphenols and eight polyphenolic compounds in PF were significantly lower than these in non-inoculation control test (CK) (P 0.05), whereas the contents of soluble sugars and theabrownins (TB) in PF were significantly higher (P 0.05) than in CK. A total of 416 volatile compounds were detected by headspace solid-phase micro-extraction combined with gas chromatography-mass spectrometry. Comparison to CK, 124 compounds in PF were degraded or decreased significantly [Variable importance in projection [(VIP) 1.0, P 0.05, fold change (FC) 0.5], whereas 110 compounds in PF were formed or increased significantly (VIP 1.0, P 0.05, FC 2). Compared with normal fermentation (NF), the levels of gallic acid, (+)-catechin, (-)-epicatechin and 64 volatile compounds in EF were significantly lower (VIP 1.0, P 0.05, FC 0.5), whereas the levels of FAA and 39 volatile compounds were significantly higher (VIP 1.0, P 0.05, FC 2). Amplicon sequencing of fungal internal transcribed spacer 1 (ITS1) revealed that P. chrysogenum P1 didn't become the dominant fungus in EF; while the fungal communities in EF were different from those in NF, in that the relative abundances of Blastobotrys bambusae and P. chrysogenum in EF were higher, and the relative abundances of Aspergillus niger and Kluyveromyces marxianus in EF were lower. Overall, inoculation of P. chrysogenum in unsterilized sun-dreid green tea leaves changed the the fungal communities in fermentation of Pu-erh tea, and chemical compounds in fermented tea leaves, i.e., the levels of TB and the compounds responsible for the stale flavor, e.g., 2-amino-4-methoxybenzothiazole were increased, resulting in improvement of the sensory quality, including mellower taste and stronger stale flavor.

Two coordination polymers (CPs) with novel tri-functional ligand, [Zn(H2O)(CH3OH)L]n (1) and [Cd(H2O)L]n (2), (H2L = 5-(1H-tetrazol-5-yl)nicotinic acid), have been synthesized and structurally characterized. Differently, 1 exhibits the 2D layer structure, while 2 exhibits the 3D structure due to the different connection modes between metal nodes and tri-functional ligand. The different coordination habit between metal ions and ligands must be responsible for the fabrication of versatile topologies. At room temperature, 1 exhibits an intense emission at around 367 nm, while 2 exhibits an intense emission at 358 nm. The different shift of the peak from free ligand, 1 and 2 must be assigned to the different configuration and π-bonding of L caused by the different coordination environments of metal ions.