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For over two millennia, the Tuareg operated the trans-Saharan caravan trade connecting the great cities on the southern edge of the Sahara to the northern Mediterranean coast of Africa. (read more)
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Međugorje (ˈmɛdʑu.ɡɔːrjɛ, roughly meh’-joo-gor-yeh) is a town located in Bosnia and Herzegovina, approximately 15.5 miles (25 km) southwest of Mostar and near the border of Croatia. The town has become well-known due to apparitions of the Virgin Mary, reportedly seen by six local children beginning on June 24, 1981. It is reported that a vision appeared nightly to the six children present, during which time ten "secrets" of future events were revealed. These apparitions are still controversial within the Catholic Church and while some authorities believe in them, they have not been officially accepted.
When word spread of these visions, millions flocked to the town for healing and absolution. The site of the visions, Podbrdo of Mount Crnica, has become known as "Apparition Hill."
Phase diagram (actinoid elements)
The inner transition elements are two series of elements known as the lanthanoids (previously called lanthanides) and actinoids (previously called actinides). They are usually shown below all the other elements in the standard view of the periodic table, but they really belong to periods 6 and 7. The lanthanoid series consists of the 14 elements cerium through lutetium (atomic numbers 58–71), which immediately follow lanthanum. Likewise, the actinoid series consists of the 14 elements thorium through lawrencium (atomic numbers 90–103), which immediately follow actinium. These elements were among the last to be discovered and placed in the periodic table. Many of the actinoids do not occur naturally but were synthesized through nuclear reactions.
Chemically, the elements within each series (especially the lanthanoids) are very similar to one another. Many lanthanoids are used for producing lasers, sunglass lenses, and strong magnets. Some radioactive isotopes of inner transition elements are used to date rocks, minerals, and fossils. The two most well-known actinoids are uranium (U) and plutonium (Pu), which are used in nuclear weapons and nuclear power plants that generate electricity.
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Written by online collaboration with certified experts.
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