18/12/2019

Ecological fertilizer from wastewater nutrients

Wastewaters contain large amounts of phosphorus and nitrogen, which are valuable nutrients. Aalto University's NPHarvest process enables recovery of these nutrients as clean ammonium sulfate and sludge containing phosphorus ...

Undersea volcanism may explain medieval year of darkness

Starting in 536 A.D., the sky went dark for more than a year. In some parts of Europe and Asia, the sun only shone for about four hours a day, and "accounts say the sun gave no more light than the moon," says Dallas Abbott, ...

How breastfeeding sparked population growth in ancient cities

Historians down the ages have examined the ebb and flow of populations in ancient societies. But most of these examinations have tended to focus on male dominated events—the wars, the politics and the money. But there is ...

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