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Tag: Heinrich Holland
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Nation & World
Brighter model for global warming
To environmental chemist Scot Martin, chemistry is a way of understanding the Earth and some of its most pressing problems. From global warming to heavy metal pollution in groundwater, Martin,…
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Nation & World
Researchers close in on date of critical rise in Earth’s oxygen
Findings by Harvard researchers and colleagues narrow the range of possible dates for a critical change in the Earth’s atmosphere. Scientists had previously believed oxygen first appeared sometime between 2.45…