Archive for category science
A very scents-able invention for detecting odors
Posted by mark in science, Uncategorized on January 23, 2022
I was impressed to see this recent New York Times ‘heads-up’ featuring a fellow chemical engineer from University of Minnesota, Chuck McGinley, who operates a lab just a few miles down the road from my home in Stillwater, MN. They got a great shot of Chuck using his Nasal Ranger to sniff around in South St. Paul, last summer. That area of the Twin Cities has emitted unpleasant odors throughout my lifetime—it being founded as a regional stockyard and still the home of a stinky rendering plant.*
“Some of the most recognizable and potent odors, like hydrogen sulfide (think rotten egg) can be sensed at even the tiniest concentrations, like 1 part per billion. ‘If you were to map out the distance from New York to Los Angeles, 1 part per billion would account for only a few inches along that route’.”
– New York Times quoting Professor Jacek Koziel, Iowa State
It turns out that there’s a surprising amount of science behind detecting and characterizing odors as detailed in this blog by St. Croix Sensory, where Chuck works as Technical Director. Unfortunately, the main focus of these experts on smelling must, by necessity, be on detection of ‘off-odors’, such as that emanating from kitty litter (yuk!). If I had a Nasal Ranger, it would be aimed at a rose garden or at a barbecue grill, that is, “on” odors.
PS: Sadly, the current coronaviruses not only cause the loss of smell but also a perverse reversal of olfactory senses called “parosmia.” This can make savory foods smell like rotting sewage as noted in a 1/18/22 report by CNBC on how Covid can turn kids into ‘fussy eaters’ if it changes their sense of smell.
*As reported in 11/22/21, Des Moines Register, ‘You can’t escape it’: Stench spoils downtown experience for some in Des Moines , the residents of South St. Paul won a settlement in 2020 for $750,000 for putting up with the off-putting odors.
Fly often, fail often, test often
Posted by mark in science, Uncategorized on September 27, 2021
Being addicted to experimenting, I greatly admire the “fly often, fail often, test often” spirit of the University of Minnesota Rocket Team. On Thursday these student rocketeers updated us engineering and other U Mn alums on their latest exploits, including a win and Overall Award in the 30k bracket of the Spaceport America Cup 2021.
Having grown up during the Space Race and celebrated my golden 16th birthday the day Apollo 11 launched off to put the first man on the Moon, I am keen to see such great leaps in technology for amateur rocketry. It astounds me that a group comprised mainly of undergrad aeronautical engineers can design and build an aircraft reaching 30,000 feet (and much higher if not prohibited by the FAA). That beats my personal-best for rocketry by 29,970 feet or so, ha ha.
“It all looked so easy when you did it on paper — where valves never froze, gyros never drifted, and rocket motors did not blow up in your face.”
Milton W. Rosen, rocket engineer and project manager in the US space program between the end of World War II and the early days of the Apollo Program.
With such great “can do” spirit, willingness to fail, and the high-tech resources of our College of Science and Engineering, the flying Gophers will go far in future, I feel sure.
Archer’s Big Bounce Experiment
I am a big fan of University of Minnesota Athletics—even more so now after they sponsored a Science of Basketball project for grade schoolers. My 9-year-old grandson Archer jumped at the chance to put a variety of basketballs to the test with my help. For the results, see the video we submitted to the UMn judges.
Archer’s findings–wood being better than rubber for bounce–stand out in graphics generated with Design-Expert software.
Archer enjoyed doing this science project. I feel sure it helped him understand what it takes to design an experiment, do it properly and analyze the result. My only disappointment is that the high-tech cell-phone app for measuring height, which I used for my experiment on elastic spheres, failed due to too much echo in the gym, most likely.
However, I discovered another intriguing basketball-physics experiment at the Science Buddies STEM website. It determines where a bouncing ball’s energy goes . This requires deployment of an infrared-temperature gun with a laser beam. Awesome! Archer will like that (if he can wrestle the laser gun away from me).
“You touch the stupid object, you change the stupid object”
So, according to the Wall Street Journal*, says Jon Pratt, a mechanical engineer with the U.S. National Institute of Standards and Technology (NIST). He was speaking about a cylinder of platinum-iridium forged in 1889, known as “Le Grand K”, which on May 20 went out of service as the kilogram standard.
Metrologists worldwide now will define this weight by non-physical methods based on non-changing constants of the universe. It will be measured by a high-tech tool called the Kibble balance.
For a detailed explanation of the new kilogram standard and a fascinating video of NIST’s Kibble balance in action, see the Wired magazine post by physics professor Rhett Allain on The Basic Physics of the Kilogram’s Fancy New Definition. Weighty stuff! (A bit too dense for me—I just like the Kibble…mesmerizing.)
*(“The Numbers” by Jo Craven McGinty, “The Kilogram Faces a New Test of Metal”, 6/8/19)
Chinese grow cotton on the far side of the moon
Early this year the Chang’e 4 (named for the Chinese Moon goddess) landed on the moon and sent out the Yutu 2 (Chinese for “jade rabbit”) for a short hop on the surface. The mission achieved a first by growing cotton. Never before has mankind grown plants on the surface of another world. Unfortunately, when the sun set (as it does every two weeks) they quickly died from the extreme cold—minus 62 F.
“Huddled together, the seedlings resembled a miniature, deep-green forest.”
– Marina Koren, “How Do Plants Grow in Space?” Jan 30, 2019, The Atlantic
The next step will be to build a sustainable garden on the moon or, better yet, Mars. Along these lines, NASA recently posted the finalists of the “BIG Idea Challenge 2019” to develop planetary greenhouse concepts. If you’d like to experiment on growing plants on the Red Planet, pick up some dirt from the Martian Garden. Students at Villanova who tried this in 2017 found that onions, garlic, kale and hops grew well, which would make an interesting diet for Mars colonists.
Science class a real blast
Making your own erupting volcano is a classic experiment to do at home or in science class. Some, such as the ammonium dichromate one in the video, should not be done without strict supervision and safety precautions.
However, the standard experimental volcano with vinegar and baking soda generally does not cause much harm; that is, until an overzealous mom in India took it to a new level with a blast that injured 59. Fortunately, as reported here, the two students who went to hospital came out intact. Perhaps a non-working volcano might be advised in future.
Fascination for pendulums piqued by Foucault’s in France
Posted by mark in science, Uncategorized on June 26, 2018
Earlier this month I visited the Pantheon in Paris where I observed this attendant recalibrating Foucault’s pendulum.
This French scientist’s elegant scientific demonstration of earth’s rotation has delighted observers like me since 1851. For more on this story read this Ask Smithsonian blog. Unfortunately, one morning in 1998, the cable on the 52-foot long pendulum at Smithsonian’s National Museum of Natural History (originally History and Technology when opened in 1964) snapped, nearly ‘clocking’ a staffer with its wayward 240-pound brass bob. This Foucault device being unAmerican and dangerous, it was removed in favor of the Star-Spangled Banner Preservation Project, thus eliminated a favored place for folks to gather.
By the way, I am now reading The Discoverers by The Librarian of Congress, Daniel Boorstin—the first in his wonderful Knowledge Trilogy. There, coincidentally, I learned that Galileo—only 19-years old at the time (1583) and bored by a church service in Pisa—became distracted by the swinging of a chandelier. By timing his pulse, he observed the time of a pendulum being independent of its arc length—an important discovery of a property called isochronism. This simple discovery, as pointed out by Boorstin, began a new age where science developed from observation and measurement rather than pure speculation.
Unearthly Stats on Spaced-Out Tesla Roadster
Spaceman calmly motoring over Earth in his Tesla Roadster
Powered by the most powerful booster since NASA’s Saturn V, the SpaceX Falcon Heavy Rocket lifted off earlier this month with a Tesla Roadster as its payload. The FHR’s two side boosters stuck their simultaneous landing as you can see and hear (double sonic booms!) here. Unfortunately, the rocket’s main booster missed its landing on an offshore drone ship. Elon Musk, CEO of SpaceX, attributed this failure to a shortfall of ignition fluid, for which the “fix is fairly obvious.”
Starman’s Tesla Roadster will be a very high-mileage car by the time it crashes back into the earth, or perhaps Venus or maybe the sun, after about 10 million years. (As detailed here the calculations remain very uncertain.) If you wonder where Starman might be, go to this website. As of today, he’s over 3 million miles away from earth, moving at a rate of 7,463 miles per hour. It’s good that Starman is a dummy because otherwise he would suffer from the worst earworms ever, having already listened to David Bowie’s “Space Oddity” 5000 times in one ear and the singer’s Life on Mars in the other ear nearly 7000 times.
Models responsible for whacky weather
Posted by mark in Basic stats & math, pop, science on August 14, 2016
Watching Brazilian supermodel Gisele Bundchen sashay across the Olympic stadium in Rio reminded me that, while these fashion plates are really dishy to view, they can be very dippy when it comes to forecasting. Every time one of our local weather gurus says that their models are disagreeing, I wonder why they would ask someone like Gisele. What does she and her like know about meteorology?
There really is a connection of fashion and statistical models—the random walk. However, this movement would be more like that of a drunken man than a fashionably-calculated stroll down the catwalk. For example, see this video by an MIT professor showing 7 willy-nilly paths from a single point.
Anyways, I am wandering all over the place with this blog. Mainly I wanted to draw your attention to the Monte Carlo method for forecasting. I used this for my MBA thesis in 1980, burning up many minutes of very expensive main-frame computer time in the late ‘70s. What got me going on this whole Monte Carlo meander is this article from yesterday’s Wall Street Journal. Check out how the European models did better than the Americans on predicting the path of Hurricane Sandy. Evidently the Euros are on to something as detailed in this Scientific American report at the end of last year’s hurricane season.
I have a random thought for improving the American models—ask Cindy Crawford. She graduated as valedictorian of her high school in Illinois and earned a scholarship for chemical engineering at Northwestern University. Cindy has all the talents to create a convergence of fashion and statistical models. That would be really sweet.
Hold on a second—the lords of time elect to extend the year of 2016
The controllers of clocks at the International Earth Rotation and Reference Systems Service (IERS) decided recently that 2016 ought to leap an extra second to stay in synch with Earth’s rotation. This will create a great deal of consternation for computers, thus IERS is giving six months’ notice for IT people to prepare themselves. Despite that lead time, about 10 percent of networks around the world are expected to fail, e.g.; a worldwide airline booking system that went down in 2012 for several hours when its computers’ internal clocks could not reconcile the discrepancy with outside systems. (I suggest you stock up on water, food stuffs and toilet paper.)
Here are some stats I gleaned from reports on this astronomical happening by New Scientist and National Geographic:
- Clocks will read 23:59:60 on the 31st of December (I am doubtful this will work on my timepieces)
- 86,400 seconds tick off every day on the master atomic clock for Coordinated Universal Time (UTC), however; the push and pull of the Moon causes the Earths massively heavy oceans to slosh around, which decelerates the spin between 1.5 and two milliseconds every 24 hours, on average.
- Gauging by sightlines from far off galaxies, IERS monitors changes to Earth’s spin. When it goes off by more than 0.9 seconds plus or minus, they mandate a 1 second adjustment.
- In 1972, when the adjustments began, the world got 10 extra seconds to make up for lost time. Since then 16 more seconds have been added—the last one on June 30, 2015. IERS have never removed a second. (If you are a rocket scientist, please compute how long it will it be until the Earth stops and let me know so I have plenty of time to begin packing up my things.)
Since antiquity the Earth’s rotation has provided us with our timescale – it is the Earth’s rotation that gives us our most basic unit of time, the solar day.
— Rory McEvoy, Curator of Horology, Royal Observatory Greenwich