Translucent material

As an example of a more speeifie applieation, Figure 2 illustrates a metallo-graph—a light microscope set up for the characterization of opaque samples. Figure 3 illustrates a research-grade microscope made specifically for materials science, i.e., for optically characterizing all transparent and translucent materials. 

Shutters were eventually added. Wlien open, they permitted light and air to enter, along with undesirable visitors, such as intruders, rain, insects, and dust. Closed shutters provided darkness as well as protection. The next addition was translucent materials such as oiled paper or animal skin, framed into window openings. 

There is bound to be one problem with resin glass polyalkenoate cement. Because the matrix is a mixture of hydrogel salt and polymer, lightscattering is bound to be greater than in the conventional material. Moreover, the zinc oxide-containing glass of class II materials is bound to be opaque. This makes it difficult to formulate a translucent material and is the reason why their use is restricted to that of a liner or base. However, the class II material cited will be radio-opaque because it uses strontium and zinc, rather than calcium, in the glass. 

When a beam of light strikes small particles in its path, the light is said to be scattered the particles send off the light incident on them in many directions. Part of a beam incident on a translucent material, for example. 

The term diffusion is also applied to the process of reflection of light by a rough reflecting surface, or of transmission of light thru a translucent material... 

Heating progressing inward may have coked the outer edges prior to the center and the volatiles from the central portion were condensed or trapped by the outer coke structure. Thin sections show that translucent material is present in some vesicles and microfissures of the outer zones of coke. This also explains the increase in reflectance as being real in this case even though coupled with an increase in volatile matter. Figure 11 shows carbon and ash plotted vs. the distance across the xenolith. As expected, the ash decreases as the distance from the contacts increases. The ash content is extremely high, from 18.6 to 37.6%. 

The theoretical basis of thin-layer densitometry by transmission is the same as that for absorption in solution. The medium provides the main differences between the two processes. For example, in solution the effects of reflected and scattered light are at a minimum, whereas such effects are significant with samples adsorbed on layers. Also, the distribution of a compound in solution is homogeneous, while that of a spot on an adsorbent is not, neither vertically nor horizontally in the layer. Shibata [42] described the phenomenon of light striking a translucent material as... 

Pyroceramic is a translucent material made by Coming that has both glass and ceramic properties. 

There are two fundamental laws to consider when we discuss absorption Beer s law and Lambert s law. Lambert s law states that equal thickness of materials cause equal amounts of absorption. Beer s law states that equal amounts of absorbing material cause equal absorption. Figure 2.5 illustrates these laws (Billmeyer and Saltzman, 1981). Both laws will only work in the absence of scattering and are not applicable in opaque or translucent materials. They are very useful in transparent materials, where the scattering due to the colorants and the polymers themselves (low refractive indices) is very low. 

Properties A translucent material with an elastic texture like para rubber. Strongest, quickest, and most waterproof explosive. It has an extremely high velocity and is rated at 100 per cent strength. It is sometimes sold under the name, Torpedo Explosive No. 1. Rate of detonation 7800 m/sec. (d = 1.63). 

Significant variation of the ultimate mechanical properties of poly(hexamethylene sehacate), HMS, is possible by con-trol of thermal history without significant variation of percent crystallinity. Both banded and unbanded spherulite morphology samples obtained by crystallization at 52°C and 60°C respectively fracture in a brittle fashion at a strain of r O.Ol in./in. An ice-water-quenched specimen does not fracture after a strain of 1.40 in./in. The difference in deformation behavior is interpreted as variation of the population of tie molecules or tie fibrils and variation of crystalline morphological dimensions. The deformation process transforms the appearance of the quenched sample from a creamy white opaque color to a translucent material. Additional experiments are suggested which should define the morphological characteristics that result in variation of the mechanical properties from ductile to brittle behavior. 

In the case of solid crystalline oxides, thermal conductivity decreases with increasing temperature but begins to rise above 1500— 1600 °C because transmission of heat by radiation (photons) begins to take a significant part besides the conduction of heat (phonon mechanism). In completely transparent materials (the coefficient of absorption a = O), no interaction with the radiation occurs in an opaque body (a = oo) the heat is transferred by conduction alone. With translucent materials, each element of the substance absorbs some of the incident radiation, and emits simultaneously,This internal radiation mechanism of heat transmission is characteristic for glasses. At high temperatures, a considerable proportion of heat is therefore transmitted by radiation the so-called apparent thermal conductivity is a sum of true conductivity with radiation conductivity ... 

Dichroic (two-color) A translucent material of two colors depending on the direction of the light. 

Existing specifications for 5 to 69 kV cables prohibit "any translucent material that is larger than 50 mil (2 mm) in its radial vector projection" and "any contaminant larger than 10 mils (0.4 mm) in its largest dimension" and limits those 2 to 5 mils (0.08 to 0.2mm) to 15 per cubic inch (0.92 per ccm) ( ). 

Again there is a light transmitter (e.g., an infrared LED) to illuminate a code disc. The code disc is made of a translucent material and is illuminated by the transmitter. A spiral shaped prism in the surface of the translucent code disc reflects the light perpendicular to the surface. Directly under the code disc there is a CMOS line sensor detecting the reflected fight. An additional reference prism in the code disc makes it possible to eliminate effects of a radial clearance. 

ATKINS, J. T. and BILLMEYER, F. w. (1966) Edge-loss errors in reflectance and transmittance measurement of translucent materials. Material Research Standards, 6, 564-569. 

Co(acac)2 NaY/PVAx are very homogeneous translucent materials. On the other hand, for [Co(acac)2trien NaY]2/PVAx the zeolite particles are clearly visible to the naked eye, in the polymer matrix. 

Although an exact explanation of the almost linear displacement in the sensitivity between these two systems is not yet available, the observations show that this difference is affected by the properties of the matrix. For example, among clear materials polycarbonate based membranes are not very effective for the broad band and UV exposures, probably because of the light absorption in the matrix. Tinted microcolumn membranes and translucent materials with interconnected pores produce even lower sensitivities. 

Glazing - A term used for the transparent or translucent material in a window. This material (i.e. glass, plastic films, coated glass) is used for admitting solar energy and light through windows. 

Glazing - Transparent or translucent material (glass or plastic) used to admit iight and/or to reduce heat loss used for building windows, skyiights, or greenhouses, or for covering the aperture of a solar collector. 

The optical parameters that are properties of the bulk of the material, transmittance, refractive index, birefringence, and haze are only applicable to transparent or translucent materials. In practice these measurements are essentially restricted to plastics, and their relevance is the same as for any other material that transmits light. 

The draft revision has additional details of procedure for thin films, which are more difficult to measure, anisotropic materials, and translucent materials. It also has diagrams of the experimental arrangements. 

There is an industrial distinction between transparent and translucent materials. Transparent bodies transmit up to more than 90% they are still mostly clear even for large thicknesses. Translucent bodies have light trans-mittances of less than 90% and are only clear for small thicknesses. They are also called contact clear, since the material is indeed turbid but appears clear as a packaging material when in contact with the contents. 

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