SEM 7nm or less
TEM 0.5nm
Microemulsions are analysed in SEM in cryogenic mode. In that mode it is difficult to get a resolution of order of 40-50 nm(which is the typical domain size of microemulsions). So TEM is a better option
in SEM you look at either backscattered or secondary electrones in TEM you look how much of your electron beam makes it through the sample onto your phosphor screen or film camera. The resolution of the TEM is better. SEM is used for looking at the surface or at the atomic composition of it. If you want to look at the surface you may have to cover the surface by a very thin (couple of atoms) thick layer of gold. TEM requires very thin sections (usually about 70nm thick) or very small structures. Biological tissue requires very good fixation and additional staining to see contrast.
TEM gives 2D images and SEM gives 3D images.
a TEM microscope privides an detailed image of the inside of a specimen a SEM microscope provides a 3D image of a specimen take for exampel a sperm in a TEM microscope you would see the inner stucture of the sperm in a SEM microscope you would se in detail the exact form shape of the sperm
In SEM (Scanning Electron Microscopy) you look at either backscattered or secondary electrones whereas in TEM (Transmission Electron Microscopy) you look how much of your electron beam makes it through the sample onto your phosphor screen or film camera. Usually SEM is used for surface analysis and TEM for analyzing sections.
The process used to produce TEM will cut cells and tissues in to ultra-thin slices so that they can be viewed under the microscope. However, the ones on SEM do not need to be cut as they can easily be visualized.
SEM, TEM, and AFM are modern imaging techniques.
chiller and freezer is same, tem is different, require tem for chiller is 0-5*C, & freezer is tem should be -18*c & above
The SEM has become more popular than the TEM as it can produce images of high resolution, greater clarity and three dimensional quality and requires less sample preparation.
SEM, which stands for Scanning Electron Microscope produces images by penetrating the specimen with a fixated beam. This beam is used to scan a rectangular portion of the specimen. Images are reliant on surface processes and they are incomplete, unlike TEM images. TEM, which stands for Transmission Electron Microscope utilizes an electron emission of high voltage. They produce complete images.
1.Scanning electron microscope (SEM) 2.Transmission electron microscope (TEM)
source of illuminatio is light in first and beam of electrons in second