The importance of knowledge from science to see the college entrance examination, scientific instruments

Learn some scientific knowledge instrument is very important, otherwise like the sudden entrance essay proposition may amusing incident. For example in 2015, Anhui college entrance essay proposition because electron microscopy do not understand, and therefore controversial (Ben was also on the news of the incident been reproduced). The following is a college entrance essay proposition in 2015 in Anhui Province.

"In order to enrich school life of students, so that students appreciate the charm of science and technology, through a cutting-edge technology addiction, Chinese Academy of Sciences Institute launched a series of public open day science activities. During the event, the researchers specially designed an interesting experiment let the students hands-on scanning electron microscope to observe the butterfly wings.

By this microscope can see nanoscale three-dimensional structure of the object, the students were surprised to find that: the original colorful butterfly wings actually lost color, showing wonderful structure uneven. Originally, this butterfly wings is colorless, but as a special microstructure, showing only the colors in the light irradiation ??

Requires optional angle to determine the conception, clear style (except poetry), since the proposed title; not out of the content and meaning of the range of composition; not intercropping, not plagiarism, shall not disclose personal information; writing specifications, proper use of punctuation. "

After the entrance, and soon, the Internet has been found in different voices from the "scientific community", the "science man" who through the analysis, pointed out that the proposition "not strict enough."

The experts also pointed out that this proposition is indeed flawed.

Electron microscope using the principle of high-energy electron beam hitting the sample surface, the surface layer (presumably microns) of the excited atoms, and then release the backscattered electron signals with a variety of atoms, secondary electrons, Auger electrons, wherein X-rays and so on. These signals are received by the electronic image obtained through the receiver, so the object color is not expressed, including butterfly included. In other words, regardless of butterfly wing color itself is really, electron micrographs show is not out.

And we can see the so-called color electron micrograph (for example, the following piece of electron micrographs) is a post-processing performed by computer software color is pseudo-color, grayscale or in essence, just became a different gray value is defined different color.

If using a confocal optical microscope because it is a xenon light source, i.e., white light. The actual imaging process under conditions of white light illumination, the object appearance (including color) integrated imaging, then, is able to see the color of butterfly wings.

Updated:2018/06/21
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