Electron microscope (Manning, n.d.) is the instrument used to magnify different scientific artifacts with the used of electron beams to create the illustration of the sample, and has the capacity to magnify two million times of the original specimen. The development of the electron microscope was first known in the year 1931 because Ernst Ruska and Maximoll Knoll magnified electron image successfully, but the equipment was actually constructed in 1933 (Innes, n.d.). The concept of the electron microscope came from Ernst Ruska’s ideas and first constructed publicly by Eli Franklin Burton at the University of Toronto together with the students. During the World War II, the advancement of an electron microscope has been controlled due to some…
The first scanning electron microscope (SEM) was invented by Manfred von Ardenne in 1937 (McMullan). However, further development of the SEM was accomplished by Charles Oatley and his colleagues at Cambridge University (McMullan; Egerton 17). He and his colleagues acquired their first images from the SEM in 1951 (Egerton 17). The SEM was developed because if a TEM is utilized, a specimen must be made extremely thin to prevent the electrons from dispersing inside the specimen and so the electrons…
1.1 Explain the appropriateness of light and electron microscopes for different purposes.
Explain the difference between magnification and resolution (2)
Magnification is how much you can enlarge an image
Resolution is how sharp and clear your microscope can show an image
State the resolution that can be achieved by each of the following types of microscope (2)
Transmission electron microscope.
Explain the appropriateness of light and electron…
levofloxacin in cocrystal formulation and pure levofloxacin respectively.
Differential Scanning Calorimetry
Thermal behaviour of the samples was determined from thermograms developed using differential scanning calorimetry (TA-60WSI, Shimadzu, Japan) calibrated with indium. Accurately weighed samples of 4 mg were placed into a flat bottomed standard aluminum pan (Shimadzu DSC-60, Japan) and scanned at a scanning speed of 10 °C/min up to 250°C under a nitrogen gas flow of 80 ml/min.
change) the volume was observed (tapped volume) and used to calculate the tapped density from powder weight.
Moisture content by thermogravimetric analysis (TGA)
The moisture contents of the supplied and spray-dried powders were determined using a thermogravimetric analyser (TA Instruments, New Castle, DE). After loading into a platinum sample pan, the powder samples (5-10 mg) were scanned at 10 °C/min over the scanning range of 25 °C to 150 °C. During scanning, nitrogen was used as a purging…
Technical Review of Hydrothermal Formation of Calcium Copper Tetrasilicate
Scanning electron microscopy (SEM) is used to obtain close-up images of samples with depth enabling high quality, 3D depictions on a microscopic level. It has been historically used to identify samples of interest such as bacterial biofilm, microtexture surfaces, and even cancer cells for diagnosis.[1, 2, 3] The first high magnification SEM was reported in a journal in 1938 by Ardenne after developing the…
Using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) images and spectra were obtained from various samples of silica and platinum on silica. Each sample contains unique structures which were prepared by etching the surface of silica in different conditions.
A scanning electron microscope is a type of electron microscope that produces images of topography and composition by scanning a sample with a focused beam of electrons. Samples can be observed in high vacuum,…
Cellular Theory & Microscopes
Robert Hooke was an English scientist credited most famously for the creation of Hooke’s Law (a principle of physics that states that the force needed to extend or compress a spring by some distance is proportional to that distance) in 1660 and the discovery of plant cells using a compound microscope in 1663.
The compound microscope uses two or more lenses, which are connected by a hollow tube. The top lens (called the eyepiece) is the one that people…
3.2 Analysis of chip formation
Fig. 7 shows the chip forms obtained during milling of the Al7075 (a) and MMCs (b) using the uncoated carbide inserts at a feed rate of 0.1 mm/tooth, machining speed of 290 m/min and axial depth of cut of 1.3 mm. The Al7075 chips formed during milling exhibited a smooth and shiny surface, and were in a semicircular and parabolic trapezoidal wave with a small radius and a saw-tooth-form, as shown in Fig. 7 (a). Fig. 7 (b) shows the chip shapes formed during the…