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Scoria differs from pumice, another vesicular volcanic rock, in having larger vesicles and thicker vesicle walls, and hence is denser.The difference is probably the result of lower magma viscosity, allowing rapid volatile diffusion, bubble growth, coalescence, and bursting.
All three sponge body plans (asconoid, syconoid, and leuconoid) can be found within the class Calcarea. Typically, calcareous sponges are small, measuring less than 10 cm (3.9 in) in height, and drab in colour. However, a few brightly coloured species are also known.
Natrocarbonatite is a rare carbonatite lava which erupts from the Ol Doinyo Lengai volcano in Tanzania within the East African Rift of eastern Africa. Natrocarbonatite lavas were first documented in 1962, by J. B. Dawson. [1] [2]
The meshing of many spicules serves as the sponge's skeleton and thus it provides structural support and potentially defense against predators. [1] Sponge spicules are made of calcium carbonate or silica. Large spicules visible to the naked eye are referred to as megascleres or macroscleres, while smaller, microscopic ones are termed microscleres.
They are porous in structure, pores being about 1–2 nanometers in size, and can therefore be targeted to absorb small amounts of matter or toxin. [2] Nanosponges are often used in medicine as targeted drug delivery systems, detoxification methods, or as a way of damage control after an injury. [ 3 ]
More than 8000 species of sea sponges live in oceanic and freshwater habitats. [1] Sponge fishing historically has been an important and lucrative industry, with yearly catches from years 1913 to 1938 regularly exceeding 181 tonnes and generating over 1 million U.S. dollars.
Texture is an important criterion for the naming of volcanic rocks. The texture of volcanic rocks, including the size, shape, orientation, and distribution of mineral grains and the intergrain relationships, will determine whether the rock is termed a tuff, a pyroclastic lava or a simple lava.
Superabsorbent polymer: Polymer that can absorb and retain extremely large amounts of a liquid relative to its own mass. [5] Notes: The liquid absorbed can be water or an organic liquid. The swelling ratio of a superabsorbent polymer can reach the order of 1000:1. Superabsorbent polymers for water are frequently polyelectrolytes.