Renal agenesis. Renal agenesis is a medical condition in which one (unilateral) or both (bilateral) fetal kidneys fail to develop.
Polycrystalline cells are composed of multiple silicon crystals, which is a cheaper way to manufacture solar modules. Put simply, these cells are easier for a factory to produce, so they are less expensive. Polycrystalline cells are made by several methods, but most commonly with a cast of molten silicon.
Microcrystalline or amorphous type graphite is made up of aggregates of fine graphite crystals, which give the material a soft, black, earthy appearance. This material is usually hosted by quartzites, phyllites, metagreywackes and conglomerates.icrocrystalline or amorphous type graphite is made up of aggregates of fine graphite crystals, which give the material a soft, black, earthy appearance. This material is usually hosted by quartzites, phyllites, metagreywackes and conglomerates.