radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon in which trace radioactive impurities were selectively incorporated when they were formed the method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products which form at a known constant rate of decay.
carbon footprint by jeff parker a carbon footprint is a measure greenhouse gases produced through our daily activities the average individuals carbon footprint is around three and a half.
Dawn ueda and tom brown next to the accelerator mass spectrometer at lawrence livermore laboratory photo courtesy of the center for accelerator mass spectrometry at lawrence livermore national laboratory figure b chinese warring states arrowhead dating to about 400200 bc dawn ueda and tom.
Composite carbon shafts are currently being produced with a more consistent wall thickness for more durability at 1378 grains per inch matched with a 100 grain point these arrows provide maximum accuracy and penetration.
Heroes and villains a little light reading here you will find a brief history of technology initially inspired by the development of batteries it covers technology in general and includes some interesting little known or long forgotten facts as well as a few myths about the development of technology the science behind it the context in which it occurred and the deeds of the many.
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The essential tech news of the moment technologys news site of record not for dummies.
The wuhan gang amp the chungking gang ie the offsprings of the american missionaries diplomats military officers revolutionaries amp red saboteurs and the old china hands of the 1920s and the heraldrunners of the dixie mission of the 1940s.
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