Harvest Rate Model. In a perfusion-based process, harvest of cell culture fluid begins significantly before cell density or titer has reached a steady state. After inoculation of the bioreactor, cells grow in batch mode until a specific cell density is achieved, at which point perfusion is initiated at a low HR.
Borax (sodium tetraborate hexahydrate or sodium borate) is a naturally-occurring mineral composed of sodium, boron, oxygen and water. It has been used as a remedy for over 4000 years. Most commercially-produced borax is mined from deposits produced by the repeated evaporation of seasonal lakes. It is found in large quantities in the Western United States, in Mediterranean countries, Kazakhstan, and the Tibet region of China. Turkey is one of the largest commercial producers of borates.
Borax is sodium borate, Na2B4O7 â¢10H2O. When borax and school glue are mixed, a more complex polymer forms. The borax molecules bond to the PVA chains, linking them together. This causes the glue to become less like a liquid and more like a solid. The slime created is a type of non-Newtonian fluid. Newtonian fluids, like water, respond in the same way to stress regardless of the rate at which the stress is applied.