Thickness section

Because of low injection pressure, some cost savings are possible in mold and press constmction. Mol ding cycles are somewhat longer than for injection molding. The part must be cooled in the mold long enough to be able to resist swelling from internal gas pressure. In stmctural foam parts there is almost a total absence of sink marks, even in the case of unequal section thickness. Stmctural foam has replaced wood, concrete, sohd plastics, and metals in a variety of appHcations. 

Some typical data for this mouldability index are given in Figure 8.8. One limitation of these data is that they do not explicitly show whether or not a mould will fill in an injection moulding operation. This will clearly depend on the thickness of the moulding, the flow distances required and operational parameters such as melt and mould temperatures. One very crude estimate that is widely used is the flow path ratio, the ratio of flow distance to section thickness. The assumption is that if this is greater than the ratio (distance from gate to furthest point from gate)/section thickness, then the mould will fill. Whilst... 

Gray iron to BS1452 A Tensile strengtii, N/mm-, of casting with section thickness of ... 

The interlaminar shear stress, t, has a distribution through half the cross-section thickness shown as several profiles at various distances from the middle of the laminate in Figure 4-54. Stress values that have been extrapolated from the numerical data at material points are shown with dashed lines. The value of is zero at the upper surface of the laminate and at the middle surface. The maximum value for any profile always occurs at the interface between the top two layers. The largest value of occurs, of course, at the intersection of the free edge with the interface between layers and appears to be a singularity, although such a contention cannot be proved by use of a numerical technique. 

Static test results may be evaluated by measurement of change of mass or section thickness, but metallographic and X-ray examination to determine the nature and extent of attack are of greater value because difficulty can be encountered in removing adherent layers of solidified corrodent from the surface of the specimen on completion of the exposure, particularly where irregular attack has occurred. Changes in the corrodent, ascertained by chemical analysis, are often of considerable value also. In view of the low solubility of many construction materials in liquid metals and salts, changes in mass or section thickness should be evaluated cautiously. A limited volume of liquid metal could become saturated early in the test and the reaction would thus be stifled when only a small corrosion loss... 

Generally, the length of thread used should be more than 1.5 times the diameter, the section thickness around the hole more than 0.6 times the diameter. Avoid having feather edges, and limit tightening with the bolt shoulder. 

Barker C, et al. Non-destructive quality control of HER2 control cell line sections the use of interferometry for measuring section thickness and implications for HER2 interpretation on breast tissue. Appl. Immunohistochem. Mol. Morphol. 2009 17(6) 536-542. 

General cytoplasmic stains are much more problematic in that a single section never contains an entire cell, even for very small cells. The only strategy that can be used for these stains is to determine a concentration per area, given that there will be variation due to the variation in section thickness and perhaps also to cytoplasmic localization of stained product. And there is simply no accurate way to determine the total amount of material within a single cell cytoplasm, unless one has a cytological (intact) specimen. 

Both resolution and statistical analyses of EM radioautographs have been discussed in depth by Evans and Callow (3) and Morel (7). Table 2 reveals that reducing section thickness as well as diameters of halide crystals and developed grains improve resolution of EM radioautographs. With regard to statistical analysis, Morel (7) considers the probability-circle method and cross-fire method for the quantitative analysis of EM autoradiographs. 

Effect of Section Thickness Emulsion Type and Development on Resolution of EM Radioautographs... 

Materials Minimum Section Thickness, (in.) Extrusion Temperature (°F) Extrusion Pressure (ksi) Extrusion Exit Speed (fpm) Extrusion Ratio InlAo/A,)"... 

Larger 3- and 4-m.e.v. Dynamitron electron beam accelerators are likewise available commercially. Service capabilities increase with the m.e.v. level of the electron beam accelerator. A 3.0-m.e.v. Dynamitron electron beam accelerator furnishes radiation capable of penetrating a maximum 370 mils of a unit density material or 185 mils of 2.0-density material other performance capabilities are doubled as well. The overwhelming majority of polyolefin plastic products now being manufactured have section thicknesses which can be penetrated safely even by a 1.5-m.e.v. electron beam accelerator. Two possible exceptions would be printed circuit board and thick-walled pipe. A 3-m.e.v. accelerator could readily meet such requirements. The performance capabilities of the 3-m.e.v. accelerator (12-ma. power supply) are increased not only with respect to maximum depth of penetration but also processing capability, which amounts to 14,000 megarad-pounds per hour at 50% absorption efficiency. 

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