The p24 antigen test can detect the p24 protein on average 10 to 14 days after infection with HIV.2,3,11,12 One drawback of this test is that levels of the p24 protein peak at around three to four weeks after exposure to HIV and are usually not detectable after five to six weeks (and sometimes even earlier).
Liquid nitrogen is nitrogen in a liquid state at an extremely low temperature.It is produced industrially by fractional distillation of liquid air. Liquid nitrogen is a colorless clear liquid with density of 0.807 g/ml at its boiling point and a dielectric constant of 1.43.iquid nitrogen is nitrogen in a liquid state at an extremely low temperature.
This is because as the water hits the hot pan, there is some vaporization of the liquid drop which creates a cushion of gas below the drop. This gas cushion can actually suspend the water droplet and cause it to skitter around the pan. Gas doesn't conduct heat as well and so it doesn't evaporate as quickly. So in the case with liquid nitrogen, it is possible that you could get that protective layer of nitrogen gas between you and the liquid nitrogen.