Polarization light microscope

A cathodoluminescence stage for a polarized light microscope that will take advantage of the x-rays generated by the electrons to detect the elements excited from single small (10—20-p.m) particles (EDS) is under development (see Luminescentmaterials,chemiluminescence). 

Some of the characteristics of materials that may be determined with the polarized light microscope include... 

The classical polarizing light microscope as developed 150 years ago is still the most versatile, least expensive analytical instrument in the hands of an experienced microscopist. Its limitations in terms of resolving power, depth of field, and contrast have been reduced in the last decade, in which we have witnessed a revolution in its evolution. Video microscopy has increased contrast electronically, and thereby revealed structures never before seen. With computer enhancement, unheard of resolutions are possible. There are daily developments in the X-ray, holographic, acoustic, confocal laser scanning, and scanning tunneling micro-... 

The general utility of the light microscope is also recognized by its incorporation into so many other kinds of analytical instrumentation. Continued development of new composites and materials, together with continued trends in microminiaturization make the simple, classical polarized-light microscope the instrument of choice for any initial analytical duty. 

We have recently initiated our investigation of blends by examining the compatibility between our modified polymer sample 4 and poly(methyl methacrylate). Mixtures with a composition of between 10% and 30% of sample 4 yield compatible blends which are transparent under a polarized light microscope, and are characterized by a single Tg. Mixtures richer than 60% of 4 undergo complete phase separation. 

Polarized light microscopy, 26 474-478 Polarized light microscope (PLM), 26 469-470, 477, 484 Polarizer, 26 470... 

Transmission signals, 11 130-131 Transmission spectroscopy, 14 228-230 examining solid samples in, 14 229 Transmitted polarized light microscope (PLM), 16 469-470... 

Table VI shows the results of polarized light microscopic observations. Sometimes isotropic regions and the middle phase exist simultaneously. The region of the middle phase is marked by heavy lines. The range of the especially viscous middle phase narrows with transition from two to three oxyethylene groups in the surfactant molecule. Up to 27 %, the system appears optically isotropic. In this concentration range the viscosity can be increased strongly by addition of NaCl, as shown in table VII.

Other cases, polymers can undergo lyotropic or thermotropic liquid crystalline phase transitions, which can often be observed and recorded in a polarized light microscope. 

The optical texture of mesophase and resultant carbons is observed readily by means of a reflected polarized light microscope and may be classified according to the shape and size of the isochromatic units. Such a classification is useful to evaluate the properties of mesophase and carbons such as needle cokes. The mesophase has been defined as the intermediate state which shows optical anisotropy and is quinoline-insoluble at room temperature (5,51) (liquid crystal glass), although it is a viscous liquid crystal during the carbonization process (6). ... 

Polarized light microscopy is a simple technique to learn and use, readily available, and of great value to differentiate between various anisotropic LC systems. It is also of value to formulation scientists investigating amphiphile-oil-water mixtures with emphasis on colloidal systems in general and MEs in particular. This is mainly due to the fact that many LC systems may appear transparent to the naked eye and can be easily misinterpreted as isotropic ME systems. Thus it becomes essential when investigating systems of amphiphile-oil-water to confirm findings based on visual appearance with polarized light microscopic examination. 

Exploiting the fact that the spindle hbers are optically anisotropic, or birefringent, with different indices of refraction in different directions (i.e., parallel or perpendicular to the hber axis), Inoue (2) developed a sensitive polarized light microscope... 

Induction times for nucleation of a tripalmitin melt at different temperatures are shown in Figure 12 (36). The tripalmitin melt was cooled quickly from 80°C to the different crystallization temperatures indicated on the figure and induction time measured as the first point of detection of crystals on a polarized light microscope. The relative time scales for the onset of nucleation are clearly shown, with the less-stable ot form taking significantly less time to nucleate than the (3 polymorph. The induction time for the most stable (3 polymorph was substantially longer than for either of the less-stable polymorphs. 

Smooth muscle is unstriated with innervations from 2 both sympathetic (flight or fight) and parasympathetic (more relaxed) nerves of the autonomic nervous system. E. Smooth muscle appears unstriated under a polarized light microscope, because the myofilaments inside are less or-ganized. Smooth muscle fibers contain actin and myosin myofilaments which are more haphazardly arranged than they are in skeletal muscles. The sympathetic neurotransmitter, Ach, and parasympathetic neurotransmitter, norepinephrine, activate this type of muscle tissue. 

Amorphous particles appear dark under polarized light microscope... 

Cocrystals can also be prepared in situ in covered depression slides on the polarized optical light microscope or Raman microscope by adding a small drop of solvent to the solid reactants. This has been shown for cocrystals of CBZ NCT with ethanol, ethyl acetate or 2-propanol. Photographs obtained through the polarized light microscope are shown in Fig. 22. These images show cocrystal formation in less than three minutes after solvent addition. In this case, the cocrystallization reaction proceeds by a similar pathway to those of macro-phase suspensions described above. In micro-phases the solvent added must allow for dissolution of both reactants so that concentrations in... 

Microscopy. A polarized light microscope (Olympus BH-2) (Olympus, Japan) was used to observe ciystal structure and to provide some indication of the relative crystal size of the shortenings. Observations were made at regular intervals. Photomicrographs were taken at 200 magnification. 

Fig. 2. Morphology map of Form II of cocoa butter obtained during the isothermal experiments of the static TTT diagram presented in Figure 1. Polarized light microscope (PLM) views illustrate the morphology observed in each domain. See Figure 1 for other abbreviation.

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