Compound optical microscope

The familiar monocular compound optical microscopes (i.e., microscopes that have a single lens as the eyepiece, or ocular, lens) are being replaced in many laboratories with binocular styles. These microscopes have a single objective lens, but two ocular ones, each in its own eyepiece. Light coming through the objective lens is split into two beams by a prism. Each eye sees the exact same image, so there is no three dimensional effect. 

High-power compound optical microscope 0.25 SOO Titania pigment, cigarette smoke... 

Optical microscopy is one of the most important scientific achievements in the history of mankind. The invention of the compound optical microscope by Hans Zaccharis Janssen in 1590 and improvements by Galileo Galilei, Robert hook, Anthony Leeuwenhoek has revolutionized all aspects of science and technology, especially the life sciences when it became possible for researcher to see, for instance, the bacteria and blood cells. 

A confocal microscope using ultraviolet light and a 1.30-NA objective is expected to produce a resolution of about 0.07 p.m (70 nm), but no such instmment has been developed. There are confocal attachments that fit on almost any compound microscope. If one of the eady twentieth century ultraviolet microscopes or a Burch reflected optics scope can be found, the shorter wavelength and improved contrast would make possible better resolution than any compound light microscope. 

Solid compounds can have four morphic states polymorphic, pseudo-polymorphic (solvates), amorphous, and desolvated solvates. Crystals usually exhibit narrow melting point ranges and defract light under an optical microscope. When a change in the arrangement of... 

Sherwood Stevens (1965) examined glass-fibre filters from personal air samplers worn by workers in the Radiochemical Laboratories at Harwell. The filters were mounted in an Araldite mixture which rendered them transparent and were covered by autoradiographic stripping film. After exposure and development, the samples were viewed with a high-power optical microscope. Particles were sized, and their activity determined from the number of alpha tracks coming from them. An extremely wide range of particle sizes, 0.2 to 90 m, was found. The smaller particles were plutonium compounds or alloys, and the larger were inert particles with one or more small Pu particles attached to them. An example of the latter is shown in Fig. 5.3. 

The compound layer thickness was determined using a conventional microhardness tester and an optical microscope. The microhardness tester was also used to put inert markers onto the surfaces of the phases involved in the interaction before each anneal of the Ni-Bi couples, except the first one when the intermetallic layer was still too thin. The microhardness indentations are known to possess advantages over other markers (inert... 

In the pressure range of 150bar, and crystallization temperature of 50°C ( 121,122), salicylic acid needles exhibit a secondary structure of small appendix.. From optical microscope observations, some needles also branch out and form long structures of 320pm and diameter of 4pm. Appendices or branches seem to be related to a high temperature in the crystallization unit in conjunction with low pressure, since they disappear when other conditions are set. On the other hand, they are specific to this compound since none of the solutes exhibits such structures in similar experimental conditions. 

Two or more substances—elements, compounds, or both—can combine physically to produce a mixture. A mixture can be separated into its components by physical means. Mixtures are physical combinations of substances that have properties related to those of their components but that do not have definite compositions. They can be either heten eneons or homc eneons mixtures. In heterogeneous mixtures, two or more different types of matter can be seen to be present with the naked eye or a good optical microscope. Homogeneous mixtures, also called solutions, look alike throughout, even under a microscope. 

Most often, fragments of paint have a multilayer structure. Each layer (about 10-50 pm thick) is made up of paint material and is a mixture of many chemical compounds. Paint smears, on the other hand, are usually made up of one or two layers of paint material mixed with and sunk into the base (e.g. among fibres of the fabric). The morphology of the paint trace can be observed under an optical microscope. The number of layers visible on a cross-section of paint chip, their colour and thickness are characteristic for the coat of paint from which it originates (Fig. 11.1). The layers are often better visible if the sample is illuminated with polarised light or if fluorescence of sample is excited by illumination with UV light. 

Figure 12 Schematic of (A) compound optical and (B) combined scanning electron microscope-microprobe analyzer. (From Ref. 82, with permission of VCH Publishers, Inc.)...

In 1971, Kuhnert-Brandstatter applied thermomicroscopy to an even narrower segment of chemical compounds, namely, organic compounds of medicinal benefit (20). Her research efforts characterized many polymorphic systems in the pharmaceutical industry. Tynan and Von Gutfeld developed a vacuum sample holder for use on an optical microscope. This accessory had the ability to characterize small samples in the 30 to 800 K temperature range (21). Schultze presented a design for a high-temperature microscope-differential thermal analyzer, which explored this role of the combination technique in the high-temperature research field (22). 

A Nicolet Magna 550 Fourier Transform Infrared Spectrometer (FTIR) and a Bruker MW 250 MHz proton NMR were used to verify the chemical structure of all monomers and polymers. Optical activity of the compounds was measured at 25 on a Perkin-Elmer Polarimeter in chloroform. A Waters Gel Permeation Chromatograph with 440 UV absorption detector and R401 differential refructometer was used to determine the molecular weights of the polymers tetrahydrofuran was used as the mobile phase at 1.0 mL/min, and the Waters polystyrene gel columns were calibrated with monodisperse polystyrene standards. Polarizing optical microscopy was used to identify liquid crystalline phases using a Leitz optical microscope with a CCD camera attachment... 

The newly formed cementite nucleates at many sites simultaneously. The resulting solid, which is a mixture of ferrite and cementite, is called pearlite because it has a lustrous appearance in an optical microscope. Pearlite is not a compound or single phase but is a microstmeture, made up of thin lamellae of cementite and a-ferrite side by side (Figure 8.7c). In this context, these phases are called eutectoid ferrite and eutectoid cementite. 

Many lay cell biologists use confocal imaging to refer to anything from a simple digital recording of a single focal plane to a full three-dimensional data By fluorescence LM, 1 mean use of a compound light (optical) microscope equipped for epifluo-... 

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