There are very few existing mosaics from the Komnenian period but this paucity must be due to accidents of survival and gives a misleading impression. The only surviving 12th-century mosaic work in Constantinople is a panel in Hagia Sophia depicting Emperor John II and Empress Eirene with the Theotokos (112234). The empress with her long braided hair and rosy cheeks is especially capturing. It must be a lifelike portrayal because Eirene was really a redhead as her original Hungarian name, Piroska shows. The adjacent portrait of Emperor Alexios I Komnenos on a pier (from 1122) is similarly personal. The imperial mausoleum of the Komnenos dynasty, the Pantokrator Monastery was certainly decorated with great mosaics but these were later destroyed. The lack of Komnenian mosaics outside the capital is even more apparent. There is only a "Communion of the Apostles" in the apse of the cathedral of Serres.
The only surviving mosaic from the Komnenos dynasty outside Constantinople is in what church?
the cathedral of Serres

Industrial production is mainly from the steam reforming of natural gas, and less often from more energy-intensive hydrogen production methods like the electrolysis of water. Most hydrogen is employed near its production site, with the two largest uses being fossil fuel processing (e.g., hydrocracking) and ammonia production, mostly for the fertilizer market. Hydrogen is a concern in metallurgy as it can embrittle many metals, complicating the design of pipelines and storage tanks.
What market primarily uses ammonia production?
the fertilizer market

In military affairs, the use of infantry with specialised roles increased. Along with the still-dominant heavy cavalry, armies often included mounted and infantry crossbowmen, as well as sappers and engineers. Crossbows, which had been known in Late Antiquity, increased in use partly because of the increase in siege warfare in the 10th and 11th centuries.[AB] The increasing use of crossbows during the 12th and 13th centuries led to the use of closed-face helmets, heavy body armour, as well as horse armour. Gunpowder was known in Europe by the mid-13th century with a recorded use in European warfare by the English against the Scots in 1304, although it was merely used as an explosive and not as a weapon. Cannon were being used for sieges in the 1320s, and hand-held guns were in use by the 1360s.
Against whom was gunpowder used in 1304?
the Scots