Chemical changes, 40,41 illus

The existence of a chemical isomer shift produced by the change in nuclear radius and differing chemical environments was first demonstrated by Kistner and Sunyar [15] in 1960 for the case of a stainless steel source and an absorber of a-FeaOs. Early work quickly showed that the chemical isomer shift measured was related to the formal oxidation state of the iron. This is illus-... 

On September 11, 2001, the terrorist attacks on the World Trade Center Twin Towers and U.S. Pentagon ended America s illusion that the continental shores of the United States were immune from direct attack by terrorists. American society was forced to change in many significant ways, the most common of which is the extraordinary precautions taken to ensure the safety of airline passengers. More shocking news came out later when it was reported that terrorists could be planning attacks on chemical plants and oil refineries. 

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