Ripe for a Revisit

I was skimming Scientific American the other day and came across this video regarding ripening fruit with powdered ethylene.
 
You will have to click on the link to view the video since it would not embed on the page, sorry.

Now, as I discussed on one of the original posts for this blog, ethylene is a gas  and a natural plant hormone used for ripening fruit.  I was a bit thrown off by the  video calling it "powdered ethylene" since compressing this gas to a solid would not be a trivial feat without being very cold or under immense pressure. Last week's post discussed that propane must be at -44 °F to even become a liquid, and ethylene is even smaller than that with two carbon atoms and four hydrogen atoms C2H4.

I did a little digging and found that the group traps the ethylene gas in a solid material made from starch.  This porous material allows the ethylene to work its way out of the solid matrix slowly and eventually fill the space surrounding it (like the shipping container with the fruit). Here is a link to the article.

It is still an interesting idea.  The material can be measured easily as a powder and it gives a slow release of ethylene in transit. This way that the food arrives ripe at a grocery store rather than having to be forcibly ripened on site.  I just wish they were a little more clear that it is not solid ethylene.

I don't know if it will catch on, but there is nothing like a ripe Mexican tomato in the depths of Minnesota January.

Time for Grillin'

Brr, it's cold out there!

Here is what my car thermometer the other morning in Northern Minnesota:

Yes, that says -10 degrees Fahrenheit.  I left this cold place for the balmy +1 °F that day. After I left, they dropped to around -30 °F.  Other than bolstering the bragging rights of Minnesotans, this cold reminded me about a fun trick my friend Mike sent me back around when I started the blog.  He is a much more seasoned and frequent social media type. He blogs for Massachusetts General Hospital,  you can check him out on twitter at @MDMorrison82

His trick was about checking the level of the a propane tank with warm water.  If you pour a glass of warm water down the side, the propane will conduct the heat away and you can find the level by feeling where the metal becomes cold.  Pretty cool!  Here is an example.

There are some other ways, such as little thermostats you can buy at the store or the traditional shake method, but the warm water is quick and easy. You could always take the straightforward route and buy a pressure gauge to put between the tank and your grill, but that may just be too logical. Here is a good summary of methods available online.

Can I Grill?

The pressing question is, can you still grill at -10 °F?  If you ignore the time to heat the metal, not freeze your hands to the utensils and to get food to a proper temperature, you may still be able to grill!   It might be a challenge to get that propane to ignite, but there should still be pressure in the tank.  People in most other parts of the country would never consider such things, but there is a point in Minnesota, where all grilling will likely cease.


Propane is a small hydrocarbon.  Essentially three carbon atoms and eight hydrogen atoms C3H8. Since it is so small and has little polarity, it has a very very low freezing and boiling point.  The measured boiling point of propane is -44 °F, that means at or below that temperature at atmospheric pressure, propane is happily a liquid.  Part of the reason propane is in tanks, is that it is pressurized to a liquid and vaporizes to a gas once pressure is released (hence it is a gas when it comes out of the burners).  Temperatures below -44 °F will result in the propane not having enough energy to become a gas and therefore no pressure at the burner.  Now, almost anywhere else, this would never be an issue, but as we know in the Great North Woods, -44 degrees is definitely possible.

Looks like International falls may be out of luck for two months of the year!

Embarrass, MN has it even worse!

How can I cook in the winter?

Various camping burners actually run the gas line through the heating zone to vaporize the gas before it gets to the burner.  This is because you are typically burning a fuel that needs much higher temperatures to build up pressure.  Back when I did a lot of camping, I bought this MSR Dragonfly stove, and it was a pretty nice setup. It is lightweight and since the pump is on the bottle, you can avoid spills. One that a troop I worked with had the Coleman 533. This has the burner attached to the bottle, but is a robust little stove. You can see the brass pipe running across the top to heat the fuel in the picture below.
 

Don't worry hunny, it's OK...

So if you "forgot" to put the grill away last fall, just tell your spouse that you were waiting for the proper time to test the physical properties of hydrocarbons by checking the boiling point of propane. The warm water trick probably will not work if the water freezes almost instantly at -10 °F though.

For a bit of extra information, the boiling point of butane, having only ONE MORE carbon atom and two more hydrogen atoms C4H10, jumps dramatically to about +30 °F, making lighting that cigarette even more troublesome in the winter.  Perhaps it would be a good New Year's resolution to quit anyway.

3D Musings

I was listening to a news blurb about 3D Televisions recently, and I began musing about the three dimensional world.  Most of us have a general understanding of dimensions from high school geometry.  Zero dimension is a point, one dimension is a line, two dimensions constitute a plane, and three dimensions has depth x, y, z if you are using a Cartesian coordinate system. 

If I asked you how many dimensions we live in, you might say 3 or maybe 4 if you want to be spry.  Perhaps you are a follower of string theory, wherefore you will give some unbelievable number. As stated on Season 1, Episode 1 of  The Big Bang Theory

Leonard: At least I didn’t have to invent 26 dimensions just to make the math come out.
Sheldon: I didn’t have to invent them. They’re there.
Leonard: In what universe?
Sheldon: In all of them. That’s the point.

Technically we live in a 3D world. Though, I am starting to think we are in a 3D world but confined to a primarily 2D plane that happens to have topography.  Yes the Earth is roughly a sphere, but human experience is basically a plane.  Regarding the other type of planes, we do go up-and down, but we always return to our pseudo-3D existence. This lead me to muse (hence the title of this post) about what things actually experience true three dimensions.

Minute Physics tells us how we know one of them.

But that is about it. Molecules will expand in 3D by diffusion. I am not sure where limit lies.  There must be some relationship between size and mass of an object for when it falls prey to the effects of gravity. Perhaps astronauts can fall into this category also, free motion in any of the space around them. Those of us who are earth-bound are gravitationally confined to this flat life.  Our cells are attached to us.  The enzymes and organelles in our cells are confined by microtubules. It is the molecules that swirl and spin and flitter about that get to experience three dimensions. 

It is one of the great challenges of chemists and chemistry students to be able to think of structures devoid of dimensional limitations.  We think in this pseudo-3D fashion and often are constrained to a 2D piece of paper for exams and notes.  Computer modelling has been a big advancement in helping to understand this 3D nature of molecules. 

Here is a model of the simple sugar glucose.  Imagine all the ways you could draw this in 2D when rotating it in 3D!

Many people are working on showing how molecules interact in 3D as a method for finding new drugs and understanding life processes. Here is a video I found on YouTube of a drug binding with a protein.  I couldn't find a reference to tell you more about it, but it is a good depiction of what pharmaceutical companies and scientists are now doing to understand the minutest interactions within the body.

Long before we had this understanding, Albert Einstein thought about this problem.  I don't know what his particular thought experiment was specifically.  In my words, he observed that small particles that should be confined to our pseudo-3D world like dust and pollen would move.  This suggested there were even smaller particles out there interacting with them.  Again, I will turn to Minute Physics to demonstrate.

So, as you go for a walk, climb a tree, or take a flight this month, think about the fact that you are living in a limited three dimensional world.  Even the lightest snowflake must fall to the ground.

If I had you convinced that molecules have it easy, remember that even they (except maybe helium) are confined to our atmosphere and don't get to just float off into space. So much for 3D.  Maybe that is why we dream of 26 dimensions.

One final note, here are how 3D TVs work!

http://www.popsci.com/gadgets/article/2010-01/its-about-time-3-d-comes-home

http://www.wired.com/gadgetlab/2009/10/3d-tv-explainer/