Mo-X4 (X = O, NH and S)-mediated triphenylene-based two-dimensional carbon-rich conjugate frameworks for an efficient nitrogen reduction reaction.

The electrocatalytic nitrogen reduction reaction (NRR) is a highly competitive approach for the ammonia synthesis to overcome the problems of high energy consumption and air pollution by the traditional Haber-Bosch process. However, the challenges of inert N2 molecule activation and the competitive hydrogen evolution reaction (HER) restrict the real utilization of the NRR. Herein, by means of density functional theory (DFT) calculations, we proposed three two-dimensional carbon-rich conjugate frameworks (2D-CCFs) with hexa-substituted triphenylene organic linkers with a metal atom Mo and functional groups X (X = O, NH, and S), namely Mo3(HOTP)2, Mo3(HITP)2 and Mo3(THT)2, to investigate their NRR performance. Our theoretical calculations reveal that Mo atoms in 2D-CCFs can efficiently capture and activate N2 molecules. Among the three structures, Mo3(HOTP)2 exhibited the most superior performance toward the NRR with a favorable limiting potential of -0.41 V and good selectivity for the HER. Furthermore, the catalytic efficiency of 2D-CCFs can be regulated by changing the atoms X in Mo-X4 motifs, providing a new scenario for the development of highly efficient NRR catalysts.

Computational Screening of Two-Dimensional Metal-Organic Frameworks as Efficient Single-Atom Catalysts for Oxygen Reduction Reaction.

The development of efficient and inexpensive oxygen reduction reaction (ORR) catalysts is crucial for renewable energy technologies. Herein, using density functional theory (DFT) methods and microkinetic simulations, we systematically investigated the ORR catalytic performance of a series of 2D metal-organic frameworks M3 (HADQ)2 (HADQ=2,3,6,7,10,11-hexaamine dipyrazino quinoxaline). It shows that all 2D M3 (HADQ)2 (M=Cr, Mn, Fe, Co, Ni, Cu, Ru, Rh and Pd) monolayers are metallic, due to π-conjugated crystal orbitals centered on the central metals and ligand N atoms. The catalytic activity of M3 (HADQ)2 depends on the binding strength between ORR intermediates and metal species, and can be tuned via changing the central metals. Among these candidates, Rh3 (HADQ)2 and Co3 (HADQ)2 show superior ORR performance to Pt (111) with high half-wave potentials of 0.99 and 0.93 V, respectively. Moreover, the screened two catalysts have excellent intermediate-tolerance ability for dynamic coverage of oxygenated species on the active sites. Our work provides a new path towards developing efficient ORR electrocatalysts.

Phytochemistry and pharmacological activities of the genus Prunella.

Prunella is a genus of perennial herbaceous plants in the Labiatae family. There are approximately 15 species worldwide, distributed widely in the temperate regions and tropical mountains of Europe and Asia. In the genus Prunella, P. vulgaris is the most studied, following a several thousand-year history as a traditional antipyretic and antidotal Chinese herb. Furthermore, since ancient times, P. vulgaris has been widely used as a cool tea ingredient and consumed as a vegetable. The genus Prunella contains triterpenoids and their saponins, phenolic acids, sterols and associated glycosides, flavonoids, organic acids, volatile oil and saccharides. Modern pharmacological studies have revealed that Prunella possess antiviral, antibacterial, anti-inflammatory, immunoregulatory, anti-oxidative, anti-tumor, antihypertensive and hypoglycemic functions. The active components related to these functions are mainly triterpenoids, phenolic acids, flavonoids and polysaccharides. This review mainly summarizes recent advances in traditional usage, chemical components and pharmacological functions.

[Analysis of different dosage forms of Xiasangju granules on fingerprints and models using high performance liquid chromatography].

To establish the fingerprints of Xiasangju granules (with sugar and non-sugar forms) by HPLC, and provide reference for their identification and effective quality control. High performance liquid chromatography (HPLC) method was used to collect the fingerprints of 20 batches of non-sugar Xiasangju granules and 34 batches of sugar type Xiasangju granules. Their main different components were classified and screened by mode identification methods (principal component analysis, PCA, and orthogonal partial least squares discriminate analysis, OPLS-DA). The principal components were identified by comparing with reference standards. The fingerprints of Xiasangju granules (sugar type and non-sugar type) were established. PCA could not fully classify the two types of granules, while OPLS-DA could obviously classify these two different types of Xiasangju granules. Six components showed greatest difference between two types of granules, including salviaflaside, luteoloside and linarin. The developed mode identification method is helpful to control the overall quality of Xiasangju granules, and it provides an effective approach to quality evaluation.

[Research on biological detoxification of Chinese medicine containing aristolochic acid A by ten microorganisms].

This paper was aim to screen microorganisms with attenualed efficiency for Chinese medicine containing aristolochic acid A by liquid-state fermentation. Twelve Chinese medicine were detected by UPLC and aristolochic acid A was only founded in four species of Aristolochia, those were Caulis Aristolochiae Manshuriensis, Aristolochiae Radix, Aistolochia Contorta Bunge and Herba Aristolochiae Mollissima,but not in the others. With the four Chinese medicine containing aristolochic acid A as raw material, ten microorganisms were tested, and the content of aristolochic acid A was detected by UPLC. The results showed that one microorganism can decrease content of aristolochic acid A in all those four Chinese medicine.