The blue and red colours of the shirt were first worn in a match against Hispania in 1900. Several competing theories have been put forth for the blue and red design of the Barcelona shirt. The son of the first president, Arthur Witty, claimed it was the idea of his father as the colours were the same as the Merchant Taylor's School team. Another explanation, according to author Toni Strubell, is that the colours are from Robespierre's First Republic. In Catalonia the common perception is that the colours were chosen by Joan Gamper and are those of his home team, FC Basel. The club's most frequently used change colours have been yellow and orange. An away kit featuring the red and yellow stripes of the flag of Catalonia has also been used.
When the colors were first worn, what team did Barcelona play?
Hispania

Among the challenges being faced to improve the efficiency of LED-based white light sources is the development of more efficient phosphors. As of 2010, the most efficient yellow phosphor is still the YAG phosphor, with less than 10% Stoke shift loss. Losses attributable to internal optical losses due to re-absorption in the LED chip and in the LED packaging itself account typically for another 10% to 30% of efficiency loss. Currently, in the area of phosphor LED development, much effort is being spent on optimizing these devices to higher light output and higher operation temperatures. For instance, the efficiency can be raised by adapting better package design or by using a more suitable type of phosphor. Conformal coating process is frequently used to address the issue of varying phosphor thickness.
What is the percentage of stoke shift loss in YAG phosphor?
less than 10%

There are two sovereign states in the isles: Ireland and the United Kingdom of Great Britain and Northern Ireland. Ireland, sometimes called the Republic of Ireland, governs five sixths of the island of Ireland, with the remainder of the island forming Northern Ireland. Northern Ireland is a part of the United Kingdom of Great Britain and Northern Ireland, usually shortened to simply the United Kingdom, which governs the remainder of the archipelago with the exception of the Isle of Man and the Channel Islands. The Isle of Man and the two states of the Channel Islands, Jersey and Guernsey, are known as the Crown Dependencies. They exercise constitutional rights of self-government and judicial independence; responsibility for international representation rests largely upon the UK (in consultation with the respective governments); and responsibility for defence is reserved by the UK. The United Kingdom is made up of four constituent parts: England, Scotland and Wales, forming Great Britain, and Northern Ireland in the north-east of the island of Ireland. Of these, Scotland, Wales and Northern Ireland have "devolved" governments meaning that they have their own parliaments/assemblies and are self-governing with respect to certain areas set down by law. For judicial purposes, Scotland, Northern Ireland and England and Wales (the latter being one entity) form separate legal jurisdiction, with there being no single law for the UK as a whole.
What is another name for the United Kingdom of Great Britain and Northern Ireland?
United Kingdom