Science Moment of the Day

Jun 08

Working as an electrical engineer

Quora: What is it like being an electrical engineer?

Apr 16

Does glass flow? No. This common myth spins off from the similarity of glass with liquids. However, once cooled, most glasses are a species of their own. Since they lack a regular structure, they are not similar to crystals. The term for this is amorphous.
Glass makers did not have the technique to make constant-thickness glass till the modern age. Furthermore, it would have been slightly advantageous to make a glass plate thicker at the bottom to create stability.
The argument against the cooled flowing glass theorem, formulated by an early chemist, lies with century old Roman glass in burial tombs and antique telescopes, both which should have shown signs of degradation.
http://www.glassnotes.com/WindowPanes.html
http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass

Does glass flow? No. This common myth spins off from the similarity of glass with liquids. However, once cooled, most glasses are a species of their own. Since they lack a regular structure, they are not similar to crystals. The term for this is amorphous.

Glass makers did not have the technique to make constant-thickness glass till the modern age. Furthermore, it would have been slightly advantageous to make a glass plate thicker at the bottom to create stability.

The argument against the cooled flowing glass theorem, formulated by an early chemist, lies with century old Roman glass in burial tombs and antique telescopes, both which should have shown signs of degradation.

http://www.glassnotes.com/WindowPanes.html

http://en.wikipedia.org/wiki/Glass#Behavior_of_antique_glass

Apr 14

Cashew nuts (Anacardium occidentale, aka Caju) are contained in olive pods beneath an upwards heart-shaped fruit. Only one per fruit, so no wonder they are expensive compared to peanuts.
The fruit itself has many medical and cosmetic uses. It can be eaten provided it is ripe, and the taste could be described as something between a quince and a pear, with the astringency of a quince or that of a cooking apple (British Bramley). However, they do spoil rapidly once picked.

Cashew nuts (Anacardium occidentale, aka Caju) are contained in olive pods beneath an upwards heart-shaped fruit. Only one per fruit, so no wonder they are expensive compared to peanuts.

The fruit itself has many medical and cosmetic uses. It can be eaten provided it is ripe, and the taste could be described as something between a quince and a pear, with the astringency of a quince or that of a cooking apple (British Bramley). However, they do spoil rapidly once picked.

Apr 10

Disclaimer
We thank you for the occasional random streak in popularity. Remember however that this blog does not endorse any ideology, product, service or belief. Especially environmentalism. Care for the surroundings comes naturally out of a well-thought design or business plan.
You see, petrol is never quite going to deplete, Earth is not hollow, there is no standard of what a boiling cuppa is in energy, we will not be baked alive by the increased UV due to that gaping ozone layer, global warming research is dodgy at best, metals will suffice till World War V and beyond, you will not receive a damaging dose of radiation if you fly frequently, windmills do not kill birds, 2012 will not give you kidney stones, and so fourth.
There is no reason to blow everything we say here out of proportion. Tumblr is not optimised for words, so the occasional summary of hundreds of pages will not give one a complete picture of the subject.
We do invite you to learn more by perusing our links or contacting us directly.

Disclaimer

We thank you for the occasional random streak in popularity. Remember however that this blog does not endorse any ideology, product, service or belief. Especially environmentalism. Care for the surroundings comes naturally out of a well-thought design or business plan.

You see, petrol is never quite going to deplete, Earth is not hollow, there is no standard of what a boiling cuppa is in energy, we will not be baked alive by the increased UV due to that gaping ozone layer, global warming research is dodgy at best, metals will suffice till World War V and beyond, you will not receive a damaging dose of radiation if you fly frequently, windmills do not kill birds, 2012 will not give you kidney stones, and so fourth.

There is no reason to blow everything we say here out of proportion. Tumblr is not optimised for words, so the occasional summary of hundreds of pages will not give one a complete picture of the subject.

We do invite you to learn more by perusing our links or contacting us directly.

Apr 09

Rare earth elements: What are they?
Nd, La, Ce, Pr, Gd… ring a bell? These are elements from the periodic table. They are not rarely occurring at all, but economically exploitable deposits containing these elements are unusual.
They are however very difficult to extract and dangerous to process. 95% of the world production comes from mainland China.
All have important applications, of which the most mainstream would be Neodymium and Samarium, commonly found in high quality speaker magnets.

Rare earth elements: What are they?

Nd, La, Ce, Pr, Gd… ring a bell? These are elements from the periodic table. They are not rarely occurring at all, but economically exploitable deposits containing these elements are unusual.

They are however very difficult to extract and dangerous to process. 95% of the world production comes from mainland China.

All have important applications, of which the most mainstream would be Neodymium and Samarium, commonly found in high quality speaker magnets.

Mar 31

Vocal chord hemorrhage

Did you know that it is possible to shout loud enough that you could make your vocal chords bleed?

Most famously, singer and songwriter Adele suffered from this, cancelling 2 tours in order to ‘prevent permanent damage’.

Our chords are not designed for prolonged shouting.

(Source: voicemedicine.com)

Mar 27

[video]

Mar 09

Ultra-low power LEDs claim over unity electrical efficiency. How is it possible to only use 30pW of electrical energy, when the output is 65pW of luminous energy?
It was discovered that diodes doped in a certain way can absorb heat from the environment. Unfortunately, this only works for cases where the voltage is nearly 0. Meaning that you won’t see ‘real life’ applications soon. But they may be used inside electronics.
A light source of a few pW would be difficult to perceive for most people, even in pitch darkness.
Homer to Lisa Simpson (after inventing a perpetual motion machine): Lisa, in this house we respect the rules of thermodynamics!

Ultra-low power LEDs claim over unity electrical efficiency. How is it possible to only use 30pW of electrical energy, when the output is 65pW of luminous energy?

It was discovered that diodes doped in a certain way can absorb heat from the environment. Unfortunately, this only works for cases where the voltage is nearly 0. Meaning that you won’t see ‘real life’ applications soon. But they may be used inside electronics.

A light source of a few pW would be difficult to perceive for most people, even in pitch darkness.

Homer to Lisa Simpson (after inventing a perpetual motion machine): Lisa, in this house we respect the rules of thermodynamics!

Mar 05

What’s the taste of umami?

Strictly speaking umami has no taste, but the sensation it leaves after the first contact with the food. Pure umami may  be found as monosodium glutamate, but due to the associated health risks, it is not recommended to consume large quantities of this.
Umami-rich foods are: aromatic vinegar, well matured cheese, soy sauce, fish sauce,  tomato sauce, teas and coffees.

Tannins and glutamates are two chemical classes that seem to contribute to the perception of savoury. Saltiness also affects this perception, even in subliminal amounts.

Feb 20

“The probability that 2 people in the same group have the same birthday is 99% in a group of 57 people, and 50% with 23 people.” —

This excepts the 29th February. Common misconceptions as these usually govern our lives. The problem is slightly different if you want to find out the probability of having the same birthday as you, at a mere 6.1% for 23 people.

Another way you could encounter the Birthday paradox is by having a very long playlist and playing the list randomly (but not shuffled, as it remembers previous plays). See here.

The understanding of this problem lead to considerable advancements in computer security… and cracking.

(Source: Wikipedia)