Problem: Light-emitting diode:

Quantum dots (QD) are semiconductor nanocrystals that possess unique optical properties. Their emission color can be tuned from the visible throughout the infrared spectrum. This allows quantum dot LEDs to create almost any color on the CIE diagram. This provides more color options and better color rendering than white LEDs since the emission spectrum is much narrower, characteristic of quantum confined states. There are two types of schemes for QD excitation. One uses photo excitation with a primary light source LED (typically blue or UV LEDs are used). The other is direct electrical excitation first demonstrated by Alivisatos et al.

Quantum Dot LEDs don't do what special skill?
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A: unanswerable

Problem: Buckingham Palace:

At the centre of this wing is the famous balcony with the Centre Room behind its glass doors. This is a Chinese-style saloon enhanced by Queen Mary, who, working with the designer Sir Charles Allom, created a more "binding" Chinese theme in the late 1920s, although the lacquer doors were brought from Brighton in 1873. Running the length of the piano nobile of the east wing is the great gallery, modestly known as the Principal Corridor, which runs the length of the eastern side of the quadrangle. It has mirrored doors, and mirrored cross walls reflecting porcelain pagodas and other oriental furniture from Brighton. The Chinese Luncheon Room and Yellow Drawing Room are situated at each end of this gallery, with the Centre Room obviously placed in the centre.

Which room has the infamous balcony forbidden by the royals?
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A: unanswerable

Problem: Chinese characters:

A commonly seen example is the double happiness symbol , formed as a ligature of and referred to by its disyllabic name (simplified Chinese: ; traditional Chinese: ; pinyin: shuangxi). In handwriting, numbers are very frequently squeezed into one space or combined common ligatures include nian, "twenty", normally read as ershi, sa, "thirty", normally read as sanshi, and xi "forty", normally read as "sishi". In some cases counters are also merged into one character, such as qishi ren "seventy people". Another common abbreviation is with a "T" written inside it, for , , wenti ("question; problem"), where the "T" is from pinyin for the second syllable ti . Since polysyllabic characters are often non-standard, they are often excluded incharcter dictionaries.

What is a commonly seen example?
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A: double happiness symbol

Problem: Paper:

Mechanical pulping yields almost a tonne of pulp per tonne of dry wood used, which is why mechanical pulps are sometimes referred to as "high yield" pulps. With almost twice the yield as chemical pulping, mechanical pulps is often cheaper. Mass-market paperback books and newspapers tend to use mechanical papers. Book publishers tend to use acid-free paper, made from fully bleached chemical pulps for hardback and trade paperback books.

What type of pulping yields nearly a tonne of dry wood per pulp tonne used?
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A:
unanswerable