A Question On Electron Microscopy (TEM)

In summary, the question asks how many fields need to be searched and what percentage of the original sample is represented when using a 0.1 mm thin section of a 1 cm3 biological sample to search for virus cells at a magnification of 100,000 on a fluorescent screen with a 15 cm diameter. The significance of the calculated values depends on the resolution and electron beam used in the transmission electron microscope (TEM).
  • #1
kranav
34
0

Homework Statement



Hello!
The question is as follows:

1. You are provided with a 1 cm3 of biological sample from which 0.1 mm thin sections are cut. A search for virus cells at a magnification of 100,000 has been proposed. The fluorescent screen on which the image is to be projected has a diameter of 15 cm.

(a) How many fields need to be searched to cover an area of 0.1 mm2?

(b) What percentage of the original sample does the searched volume represent?

(c) Comment on the significance of the calculated values.


Homework Equations





The Attempt at a Solution



I don't know of any formulas for this question.
The magnification might be a key here.
Can I find the resolution of the TEM using this?
or maybe the max distance squared I get at 100000 mags (one field) and then use that to calculate the total number of fields to cover 0.1 mm2 ?

In the second part I can do the same (find the area at 100000 mags) and get the percentage.

thanks.
 
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  • #2
What is meant by field ?
Resolution depends on the wavelength/energy of electron beam used in TEM.
 

1. What is Electron Microscopy (TEM)?

Electron Microscopy (TEM) is a scientific technique that uses a beam of accelerated electrons to produce high-resolution images of the surface and internal structure of a sample. It is often used in fields such as materials science, biology, and nanotechnology.

2. How does Electron Microscopy (TEM) work?

Electron Microscopy (TEM) works by using a beam of electrons that is focused onto the sample. The electrons interact with the sample, producing signals that are then detected and used to create an image. The resolution of TEM is much higher than traditional light microscopy, allowing for the visualization of smaller structures.

3. What is the difference between Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM)?

Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) are two different types of electron microscopy techniques. TEM produces images by passing electrons through a thin section of the sample, while SEM produces images by scanning a beam of electrons over the surface of the sample. TEM is often used for high-resolution imaging of internal structures, while SEM is better suited for imaging surface features.

4. What are some applications of Electron Microscopy (TEM)?

Electron Microscopy (TEM) has a wide range of applications in various fields of science and technology. It is commonly used in materials science to study the microstructure of materials, in biology to examine the internal structure of cells and tissues, and in nanotechnology to analyze the structure of nanoparticles. It can also be used for forensic analysis and quality control in industries such as pharmaceuticals and semiconductors.

5. What are the limitations of Electron Microscopy (TEM)?

Although Electron Microscopy (TEM) has many advantages, it also has some limitations. One of the main limitations is that the sample must be thin enough for the electrons to pass through, which can be challenging for some materials. Sample preparation for TEM can also be time-consuming and requires specialized equipment. Additionally, TEM can only produce black and white images, and the sample must be conductive or coated in a conductive material, which may alter its properties.

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