Monday, 14 December 2020

Coronavirus: USA begins massive vaccine rollout as crisis worsens


9 News Australia shows that the USA will begin rolling out the Pfizer coronavirus vaccine, as the nation's Coronavirus COVID-19 case count surpasses 16 million.

Right now, Pfizer says its vaccine needs to be kept at minus 70 degrees Celsius and can last in a specialty freezer for up to six months. The vaccine must be stored at the ultra-cold temperature of -70°C. That means the vaccine must be kept in specialized freezers that cost as much as $20,000 each. These freezers are rare outside of medical research facilities.

What is dry ice? Dry ice is solid. It sublimates or changes states from a solid to a gas at temperatures of -78 degrees Celsius under normal atmospheric pressure of 1 atm. Because of its low temperature at normal atmospheric pressure, it is useful as a coolant. When dry ice is placed into warm water, a cloud forms.

How long does dry ice last? This is based on an average five-pound brick of dry ice that remains whole (not broken into pieces). In a cooler: 18-24 hours. Outdoors: 3-5 hours. In liquid: 15-45 minutes.

These materials can be compared: Dry Ice Vs. Liquid Nitrogen. 

When regular ice melts, it turns into a liquid. When "dry ice" melts, it sublimates at room temperature (meaning it goes directly from a solid to a gas). These characteristics make dry ice valuable for keeping food cold without refrigeration.

Liquid Nitrogen is also interesting. Nitrogen is a gas. To make it a liquid, it has to be cooled intensely. At typical liquid nitrogen temperature of -346°F, it looks like boiling water, even though it is extremely cold. When it is frozen below -346°, it becomes a solid. When taken above its boiling point of -320.44°F, it becomes a gas.

Liquid nitrogen is much colder than dry ice. Liquid nitrogen could do amazing things. A banana can be freezed in liquid nitrogen. You could use the banana to hammer a nail. Liquid nitrogen expands quickly and freezes objects immediately.

The useful controversial process known as "fracking" takes advantage of liquid nitrogen's rapid expansion to fracture rock formations that contain natural gas.

Hydraulic fracturing, also called fracking, fracing, hydrofracking, fraccing, frac'ing, and hydrofracturing, is a well stimulation technique involving the fracturing of bedrock formations by a pressurized liquid.

Some or all of the fluid used in hydro-fracking is replaced by nitrogen gas which can fracture rock at high pressures, much like water. The nitrogen is used to energize the liquid phase fluid, increasing flow back (less water certainly remains trapped in the ground during fracturing of low pressure formations).

You might have thought about what are the coldest materials on earth. So, what is one of the coldest substances known to man? Liquid hydrogen. Liquid hydrogen is the coldest substance known to man, minus 400 degrees.

What's the coldest liquid on Earth? Liquid helium. Liquid helium has a boiling point of -452 degrees F below zero; it is the coldest material known. It is also the only material on earth that never exists as a solid, only as a cryogenic liquid and as a gas.

Cryogenic liquids are liquefied gases that are kept in their liquid state at very low temperatures. The word "cryogenic" means "producing, or related to, low temperatures," and all cryogenic liquids are extremely cold. The vapours and gases released from cryogenic liquids certainly also remain very cold.

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