Pollen are the tectum and the foot layer, which is just above the intine. The tectum and foot layer are separated by a region called the columella, which is composed of strengthening rods. The outer wall is constructed with a resistant biopolymer called sporopollenin. Pollen apertures are regions of the pollen wall that may involve exine thinning or a significant reduction in exine thickness. They allow shrinking and swelling of the grain caused by changes in moisture content. Elongated apertures or furrows in the pollen grain are called colpi (singular: colpus) or sulci (singular: sulcus). Apertures that are more circular are
Water-based pipe coating pipe flanges and fittings, gray iron pipe (sewer lines), storm water sealing, utility box sealing, and septic tank and vault sealing. Water-based pipe coating A water-based pipe coating is an environmentally friendly coating that is applied to the inner and outer surfaces of ductile iron pipe. The coating serves to protect the water supply lines from corrosion whether from the outside or the inside. It also serves to protect the drinking water from contamination. The coating is an emulsion manufactured using asphaltene and water primarily, with other raw materials according to the manufacturer’s specifications. Water-based coatings began development in the