Zunic,+Jacquelyn

I read the article about the pigmentation of dinosaurs. I knew that birds use their plumage for protection and to attract a mate. I also knew about the dark pigmentation called eumelanin, which is in brown human hair. The third thing I previously knew from this article is that x-rays are not invasive and that is why they are used for delicate things like humans and fossils.

I learned that there are slow chemical reactions that have been occurring for ten million years in some of the fossils, which is an extremely long time for a chemical reaction to happen. The majority of the chemical reactions we will experience in class will take a fraction of a second, so I thought this was a very long amount of time. I learned that they can determine the colors of plumage because the metals that are in trace amounts are not biodegradable. Finally, I discovered that scientists can use modern birds to determine how the colors of ancient birds would look.

Jacky, I'm glad you found this article interesting! Well done! 5 stars. MW

Due: 9/21 I did not know that crude oil was actually useless as a mixture, its natural state. I learned that it is separated through fractional distillation, which creates the products of asphalt, petrol, diesel, kerosene, fuel oil, bottled gas, and naphtha. These are all parts that boil at different points, and therefore are easily separated this way. The temperatures used vary from about 25°C to 330°C, so that each part in the column boils. The heat is only created at the bottom, so certain parts only survive as vapors to a certain height in the column, which is translated to be a specific temperature.

Jacky, Well written and insightful! 5 stars. MW

Due: 10/6 I knew that infrared was used as a motion detector, and that echoes could be used to find objects as well. I also knew that the photo-electric effect was that specific wavelengths of light, when shined on a material, gives off electrons. The third thing I knew was that the electromagnetic spectrum contains only a portion of visible light, the color spectrum, which is what we can see. This is a very short wavelength range, only about 400-500nm apart in the wavelength.

I learned that humans give off infrared radiation, which is how infrared detectors work. I also learned that when motion detectors are a beam of electromagnetic radiation, they have to be broken in order for the detection to work. When someone or something passes through the beam, it is broken and sets off a mechanism to complete the task (turning on a light or stopping a garage door from being closed). The final thing I learned was that Einstein won a Nobel Prize in 1921 for the photo-electric effect.

Jacky, Solid post. 5 stars! BTW - The visible range is actually 400-750 nm. MW