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Category: Educational (Page 1 of 14)

Educational topics and useful things to know.

High-Performance Masks

High-performance masks are now available.

Example high-performance mask

High-Performance Mask

High-performance masks are made to a specification that exceeds the filtration efficiency of industry standard masks. They deliver this performance on particles down to 10 nanometers, which exceeds NIOSH specifications. All masks are equipped with a robust non-springy nose wire that can be shaped to seal to your face and nose.

If you want a reusable mask that looks nice and outperforms industry standard masks, you have found it here. They look the same as the standard masks but weigh slightly more because they contain three layers.

How do these masks work? In April of 2020, six researchers decided to collect samples of numerous fabrics used to make reusable masks and measure their filtration efficiency with the same equipment used to test industry standard masks like the N95. Since the topic here is viruses, the researchers enhanced the testing setup with a particle generator producing particles down to just 10 nanometers in size, making the test even more demanding.

Cotton, flannel, silk, and other materials were tested at 1, 2, and 4 layers, and then in various combinations. The researchers expected a cotton/silk combination to perform the best because of the electrostatic interaction between the two materials. Cotton/silk showed 92 percent efficiency. But, they discovered that cotton plus 90/10 chiffon performed even better, reaching 97 to 98 percent efficiency.

This work appears in a peer reviewed scientific paper published by the American Chemical Society here:

https://pubs.acs.org/doi/10.1021/acsnano.0c03252

High-performance masks are made with an outer layer of high thread count cotton, an inner layer of 90/10 chiffon, and a comfortable inner layer of cotton muslin like the standard masks.

Get them here: https://www.ebay.com/itm/254577982386

Coronavirus Covid-19 Quizzes

In the interest of getting more information on the Covid-19 virus out and in easily digested form, I’ve developed three educational quizzes. Those quizzes have been added to my existing quiz web site.

The Covid-19 virus is new and much is being learned. New discoveries are made and our knowledge refined every day. There are changes in what’s known every day. In compiling information for these quizzes, I found many examples where information published a week or two ago is already obsolete. These quizzes are based on the best information I could find as of March 18, 2020.

I will do my best to keep these quizzes up to date. Please comment here on this blog post with any updates or incorrect information you may find. Ideas for additional questions or additional quizzes are welcome. In fact, this blog post exists so that you have a place to leave comments.

Click here to go to the quizzes.

My Vote Counts More Than Yours

In presidential elections, not all votes are equal. Wait. What? But, this is a democracy — one person, one vote, right? No.

Two hundred years ago, the founders designed a presidential voting system that gave rural farmers and ranchers in states with low population more voting power than people in urban areas. Among other things, the Electoral College was designed to try to avoid a tyranny of densely populated urban areas over other, less populous, areas of the country. It worked okay through the 1800s and most of the 1900s. But, the founders never imagined an organized, scientific effort to take advantage of the voting power imbalance in order to seize power.

So, exactly what are the numbers? The power of a voter in Wyoming is almost four times that of a person living in Texas. Whether this is fair and appropriate is for you to decide. See below for how much your vote counts.

Presidential Voting Power in Each State

 

Understanding Whipped Cream

I use cream for cooking and also make whipped cream for desserts, a quart at a time, about once a day. Sometimes I make it several times a day. These are sweetened with sugar and flavored with vanilla, sometimes banana, lemon, or chocolate.

Doing this for years with a hand mixer, I’ve noticed big differences between brands and types of cream. My favorite that I use the most is Glenville Farms Heavy Cream. It whips fast, becomes very stiff, and is stable. You can quickly ice a cake with it and it stays put. It never creeps or sags. This cannot be said of any other brands I’ve tried, and I’ve tried all kinds.

If you make things with whipped cream, you might like to know why Glenville is the best I’ve found and what to look for. Cream is cream, right? It’s the stuff at the top of raw milk. Not exactly. It varies.

What varies is the fat content. The higher the fat, the faster it will whip and the more stiff and stable it will be. Fat is expressed as a percentage. Finding out the percentage can be challenging because it’s usually not printed on the carton or bottle.

The minimum fat content needed for it to whip at all is 30 percent. Some brands get by with even less by adding a thickening agent like carrageenan. Look for it in the ingredients. You can recognize this as it flows out of the bottle as a very thick gloppy liquid. Real cream is thick but still flows smoothly like a liquid. The result of low-fat-content cream will be okay for some purposes but will be soft, light, less stable, less flavorful. This is often labeled “whipping cream”. A better result occurs with fat content of 37 to 38 percent and this often labeled “heavy cream”. Glenville has 40 percent and its superiority is evident in the result and flavor.

I was going to publish a list comparing different brands, but accurate info is difficult to get hold of, so I decided not to, for now. What I found, however, was something to beware of if you are a dieter or paying close attention to nutrition. I found that several nutrition sites on the web do not show accurate information. Some sites allow you to search products by brand and type. I found that the information they publish for all brands and types of cream is identical. They just copy-pasted the exact same information on every brand and type — the same calories per tablespoon, the same grams of fat per 15 ml. We know that’s not true.

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