QUES: The structure of QD-LEDs used for the electrical-excitation scheme is similar to basic design of OLEDs. A layer of quantum dots is sandwiched between layers of electron-transporting and hole-transporting materials. An applied electric field causes electrons and holes to move into the quantum dot layer and recombine forming an exciton that excites a QD. This scheme is commonly studied for quantum dot display. The tunability of emission wavelengths and narrow bandwidth is also beneficial as excitation sources for fluorescence imaging. Fluorescence near-field scanning optical microscopy (NSOM) utilizing an integrated QD-LED has been demonstrated.

What is one scheme of Quantum Dot excitation?
What is the answer?
ANS: electrical-excitation
QUES: Throughout its prehistory and early history, the region and its vicinity in the Yangtze region was the cradle of unique local civilizations which can be dated back to at least the 15th century BC and coinciding with the later years of the Shang and Zhou dynasties in North China. Sichuan was referred to in ancient Chinese sources as Ba-Shu (巴蜀), an abbreviation of the kingdoms of Ba and Shu which existed within the Sichuan Basin. Ba included Chongqing and the land in eastern Sichuan along the Yangtze and some tributary streams, while Shu included today's Chengdu, its surrounding plain and adjacent territories in western Sichuan.

How far back can civilizations in the Changdu region be dated?
What is the answer?
ANS: unanswerable
QUES: 
 Turkey: The torch relay leg in Istanbul, held on April 3, started on Sultanahmet Square and finished in Taksim Square. Uyghurs living in Turkey protested at Chinese treatment of their compatriots living in Xinjiang. Several protesters who tried to disrupt the relay were promptly arrested by the police.

What happened to protesters who tried to interrupt the carrying of the torch?
What is the answer?
ANS:
arrested