The origin of the chemical elements in the Universe is one of the most fascinating and enduring mysteries in astronomy. Progress so far has come from studies of stars, but here only elemental ...

This is a preview. Log in through your library . Abstract Background: Anthropogenic nitrogen (N) addition has dramatically increased and significantly affected global nitrogen cycling. The natural ...

This is a preview. Log in through your library . Abstract Nitrification of the environment has resulted from tremendous increases in the use of fertilizers for crop plants. This has increased runoff ...

A new study of stable isotopes in ancient rocks suggests that the oceans were much cooler 3.4 billion years ago than previously thought. The discovery that the ocean could have been cooler than 40 °C ...

China has achieved a major breakthrough in obtaining kilogram-level abundance 99 percent molybdenum-100 isotope for the first time, marking a significant milestone in the independent supply of key ...

Chinese scientists have achieved a breakthrough in low-temperature distillation of boron-10 isotopes to stably produce enriched boron-10 products with an abundance of 70 percent, significantly ...