But it wasn't until new types of semipermeable plastic films were developed in the late 1980s that TransFresh could begin to control the atmosphere within a sealed plastic bag.
42.
"' Osmotic pressure "'is the minimum pressure which needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane.
43.
An increased absorptive area is useful because digested nutrients ( including monosaccharide and amino acids ) pass into the semipermeable villi through diffusion, which is effective only at short distances.
44.
"' Tonicity "'is a measure of the effective osmotic pressure gradient, as defined by the water potential of two solutions separated by a semipermeable membrane.
45.
When heat is transferred, a thermally-conductive membrane is used between the two tubes, and when the concentration of a chemical substance is transferred a semipermeable membrane is used.
46.
Further improvement of the dialytrode concept resulted in the invention of the " hollow fiber ", a tubular semipermeable membrane with a diameter of ~ 200-300?m, in 1974.
47.
Jones and collaborators at the university's Center of Marine Biotechnology have built a prototype cell that exposes a living colony of the bacteria to seawater samples filtered through a semipermeable membrane.
48.
Once the vaccine is given, the site is covered with gauze and two layers of a semipermeable bandage that is meant to keep the virus from leaking out and infecting other people.
49.
The microdialysis probe is designed to mimic a blood capillary and consists of a shaft with a semipermeable hollow fiber membrane at its tip, which is connected to inlet and outlet tubing.
50.
Some hospital officials say that newly vaccinated workers who take care of patients will be required to wear special semipermeable bandages at work, because they are better than gauze at containing the virus.
