Carbon dioxide (CO 2) is usually pumped as a liquid, usually below 5Â°C (41Â°F) and a pressure of about 50 bar. The solvent is pumped as a liquid as it is then almost incompressible; if it was pumped as a supercritical fluid, much of the pump stroke would be used up in compressing the fluid, rather than pumping it.
The word lice is plural for louse. Head lice are spread by personal contact or the sharing of combs, brushes, caps, and other clothing. Head lice are a common problem with preschool and schoolchildren. Head lice cause a tickling feeling of something moving in the hair, itching, and sores on the head.
By Adam Ward. Adult lice and nymphs (baby lice) are grayish white or tan in color. If you look at an adult louse (see lice pictures), you may be able to see its abdomen filled with the red human blood it has been feeding on. Lice eggs (called nits) look like tiny yellow, tan or brown dots before they hatch. If you pull one off the hair, it may look like a flat speck with a tiny tail (which is the residue of the hair shaft it was glued to). After hatching, the remaining nit shell looks white or clear.