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The MABFT high-density biological enrichment special denitrification process (modified aeration biological fluidized tank) is applied to the high ammonia nitrogen wastewater treatment project formed by digital printing. The results showed that when the influent NH3-N ≤ 300 mg/L, the effluent NH3-N ≤ 10mg/L treated by MABFT technology, the average removal rate of ammonia nitrogen was as high as 98.9%, and all indexes in effluent would meet the requirements of the People's Republic of China’s Discharge standards of water pollutants for dyeing and finishing of textile industry for new plants. Providing reference for the treatment of similar high ammonia wastewater.

Troilite-orthopyroxene intergrowths are present as a common material in the brecciated diogenite Northwest Africa (NWA) 7183. In this study, we report on the petrographic, mineralogical, and rare earth element abundances of the troilite-orthopyroxene intergrowths to constrain their origin and assess their implications for the diverse petrogenesis of diogenites. Two groups of troilite-orthopyroxene intergrowths with various grain sizes and mineral chemistry have been observed in NWA 7183. One group of intergrowths contains fine-grained (

Isoprenoids are the most abundant and highly diverse group of natural products. Many isoprenoids have been used for pharmaceuticals, nutraceuticals, flavors, cosmetics, food additives and biofuels. Carotenoids and isoprenoid-based biofuels are two classes of important isoprenoids. These isoprenoids have been produced microbially through metabolic engineering and synthetic biology efforts. Herein, we briefly review the engineered biosynthetic pathways in well-characterized microbial systems for the production of carotenoids and several isoprenoid-based biofuels.

The Pb electrode is the most efficient and selective catalyst in reducing CO2 into HCOOH; however, the reaction mechanism remains elusive. Herein, we have investigated the mechanism of CO2 electroreduction to HCOOH on the Pb(111) surface using density functional theory calculations. We find that the effects of solvation and cations lead to different active intermediates for CO2 electroreduction (HCOO in gas-phase condition, both HCOO and COOH in solvent condition, and COOH in cation solution). In particular, the size and hydrophilic/hydrophobic nature of the cations are found to significantly affect the reaction selectivity and efficiency of CO2 electroreduction at different overpotentials. These findings rationalize several experimental observations and contribute to a thorough understanding of CO2 electroreduction.

Thiolate-protected gold nanoclusters, Aum (SR)n , have potential applications in many fields due to their high stability and remarkable electronic properties. However, the controlling factors in determining the stability and HOMO-LUMO gap of Aum (SR)n remain controversial, despite decades of work on the topic. Through DFT calculations, including nonlocal many-body dispersion (MBD) interactions, the geometric and electronic properties of Aum (SR)n clusters are investigated. Calculations demonstrate that the MBD interactions are essential for correctly describing the geometry and energy of the clusters. Greater anisotropic polarization and more atoms distributed in the shell of the clusters lead to more pronounced MBD interactions and higher stability of the clusters. Furthermore, the HOMO-LUMO gap of the clusters strongly depends on the gold core. These results provide critical clues for understanding and designing Aum (SR)n clusters.

Sucrose and molasses are attractive raw materials for industrial fermentation. Although Corynebacterium glutamicum shows sucrose-utilizing activity, sucrose or molasses is only a fraction of carbon source used in the fermentation medium in most works. An engineered C. glutamicum strain was constructed for producing L-ornithine with sucrose or molasses as a sole carbon source by transferring Mannheimia succiniciproducens β-fructofuranosidase gene (sacC). The engineered strain, C. glutamicum ΔAPE6937R42 (pEC-sacC), produced 22.0 g/L of L-ornithine with sucrose as the sole carbon source, which is on par with that obtained by the parent strain C. glutamicum ΔAPE6937R42 with glucose as the sole carbon. The resulting strain C. glutamicum ΔAPE6937R42 (pEC-sacC) produced 27.0 g/L of L-ornithine with molasses as the sole carbon source, which is higher than that obtained by the parent strain C. glutamicum ΔAPE6937R42 with glucose as the sole carbon. This strategy can be applied for developing sucrose- or molasses-utilizing industrial strains.