Polarization microscope

Figure 1 illustrates a typical, good quality, analytical polarizing microscope. Polarizing microscopes are extraordinarily versatile instruments that enable the trained microscopist to characterize materials rapidly and accurately. 

Figure 11 Polarized microscope photographs ( x 800) (A) PBT-TLCP-elastomer blend (60 25 15 wt ratio). Dark phase is the TLCP phase. (B) Nylon 6-TLCP-elastomer blend (60 25 15 wt ratio). Dark phase is the TLCP phase and large white one is the elastomer phase. Source Ref. 56.

As shown in Fig. IIB, dispersion morphology for the nylon 6/Vectra B/SA-g-EPDM blend was totally different from that of the PBT-Vectra A-SA-g-EPDM blend. TLCP phases were very uniformly and finely dispersed in the nylon 6-Vectra B-SA-g-EPDM blend and a large fibril shape observed in the PBT-Vectra A-SA-g-EPDM blend could not be seen under polarized microscope. It should be noted that the size of the dispersed TLCP phase is very small (submicron size). This small size of the TLCP phase in the nylon 6/elastomer matrix was not observed by any others [4,54,55,58]. A closer look by SEM more clearly revealed the dispersion of Vectra B in the matrix (Fig. 12B). TLCP phases are very... 

For more precise work, micro hot stage methods under a microscope are used. For all compds, except those which are isotropic or become so on heating, the mp can best be observed by means of a polarizing microscope, since the temp at which color disappears arid the space lattice is ruptured is the true mp. Among numerous models of micro-hot stages, the Kofler micro-hot stage has attained widespread use and is commercially available (Refs 3 4)... 

N.H. Hartshorne and A. Stuart, Practical Optical Crystallography, Arnold, London, 2nd edn., 1969 Crystals and the Polarizing Microscope, Arnold, London, 4th edn., 1970. 

Figure 3. Structure of a muscle sarcomere. In a polarizing microscope muscle appears to have dark (A) and light (I) bands. The l-band region only contains thin filaments. The A-band region contains both thick and thin filaments. One sarcomere is the distance between two Z-lines. In cross section, the hexagonal packing of the thick and thin filaments can be seen.

Hartshome, N. H. Stewart, A. Crystals and the Polarizing Microscope Arnold London, 1970. 

Bone, R. A. and G. Draper (2007). Optical anisotropy of the human cornea determined with a polarizing microscope. Allied Optics 46 8351-8357. 

The compensation birefringence measurement is very easily coupled to optical microscopy in the transmission and reflection modes, thus allowing characterizing orientation with a spatial resolution of a few hundreds of nanometers [14]. Polarizing microscopes are widely available and are often used for birefringence studies even if spatial resolution is not required. Objectives specifically designed for cross-polarized microscopy are necessary to avoid artifacts. 

Under the polarizing microscope, both polymorphs of (ii)-penicillamine were seen as anisotropic crystals, with Form I existing as needles and Form II as plates. 

Figure 7.1 Illustration of different aggregation states obtained (from left to right) by increasing temperature crystal (K), smectic C (SmC), nematic (N) and isotropic (I). Row a shows macroscopic appearance of samples in row b, short-range microscopic ordering is represented (each bar represents a molecule) thermotropic phase diagram of row c illustrates relevant transition temperatures (Tm melting temperature Tsmc-N transition temperature between SmC and N Tc clearing temperature) row d shows different texture of different states as seen through polarizing microscope (with crossed polars, isotropic phase appears black).

Abundant fragmental sand- to pebblesized deposits at several Fluid Collection and Recycling System (FCRS) locations in MGPF (Fig. 1 and Table 1) were collected and analyzed using a polarizing microscope. 

The abundant dark brown to black soft minerals in the collected samples are identified as smectite, based on optical properties under a polarizing microscope. 

A polarizing microscope for transmitted light usually has a polarizer at a fixed azimuth beneath the substage condenser, and an analyzer in the microscope tube above the objective. Typically, a compensator is inserted at 45° beneath the analyzer. Some compensators (such as the de Senarmont) are fixed in azimuth, and measurements are made with a rotary analyzer with a variable azimuth. For other compensators, the analyzer is fixed and the compensator is rotated or tilted to make measurements in the axis of the microscope. 

A hot-stage-equipped polarizing microscope was used for measurement of these parameters. The anisotropic melting temperature (Tn) was determined as the onset temperature of stir-opalescence observed on the hot-stage. The liquid crystalline-isotropic transition temperature (71) was also determined by the use of the hot-stage-equipped microscope. 

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