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praseodymium, Pr, atomic number 59 | a soft yellowish-white trivalent metallic element of the rare earth group; can be recovered from bastnasite or monazite by an ion-exchange process | |
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public relations, PR | a promotion intended to create goodwill for a person or institution | |
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Puerto Rico, PR, Porto Rico, Commonwealth of Puerto Rico, Puerto | a self-governing commonwealth associated with the United States occupying the island of Puerto Rico |