We build a simplified externality model extended into global monetary field and get the conditions from the worst, basic to best disciplines about the issuances of national and international currencies. Then, we assess and design several international monetary systems. We find for the national...

Using household-level survey and housing transaction data, we detect the flight to safety vis-a-vis housing in China: Great economic uncertainty causes the prices of housing assets to soar, especially those of good quality. To stabilize housing prices, China has imposed purchase restrictions on...

The effect of the ammonia nitrogen stress intensity on methanogenesis and the ammonia conversion pathways in anaerobic digestion systems is unclear. Here, we analysed the changes in the assembly mechanism, biodiversity, and function of microbial communities after gradually increasing the ammonia...

The effect of the ammonia nitrogen stress intensity on methanogenesis and the ammonia conversion pathways in anaerobic digestion systems is unclear. Here, we analysed the changes in the assembly mechanism, biodiversity, and function of microbial communities after gradually increasing the ammonia...

Nitrite is an important intermediate in nitrogen metabolism. We explored the effect of nitrite-nitrogen stress intensity (NNSI) on nitrite metabolism and methanogenesis in anaerobic digestion. The results showed that the NNSI regulated microbial diversity, composition, and functions, and...

Nitrogen, an essential component of all living organisms, is a major limiting nutrient. Nitrite is an important intermediate in nitrogen metabolism. Both the nitrification of high levels of NH4+-N and denitrification of NO3--N in wastewater typically results in the accumulation of high...