Manifold elongation

The periodic phenomenon described above indicates that the entire channel acts like the area beneath a growing bubble, going through periodic drying and rewetting. The cycle was repetitive with venting of the elongated bubble. Such a behavior affects the mean flow characteristics that usually are measured at the manifolds. 

The most interesting features are the traces of mechanical movements which gave rise to manifold or stretched halos. These movements occurred when the material was plastic and still sensitive to irradiation (Figure 2e, g). One may observe halos separated from the uranium minerals which remain only as fine threads other elongated halos have one end showing a sharply defined limit, and the other fading out smoothly. 

Conventional hybridization assays on membranes are known as dot blots or fine probes, depending on the geometry of the individual spots. The nucleic acids are applied with suction, using a commercially available manifold that results in a shape that is either round (dot) or elongated (line or slot). After immobilization, the membrane is incubated with complementary nucleic acid at a constant temperature, followed by one or more washes to discriminate matched from mismatched nucleic acid. The method allows multiple... 

During heating, the manifold is, however, subject to elongation (approximately 0.1 mm/ 100 mm at 100 °C), which causes skewing and stretching of the bolts with the passage of time, there may be a fall in the pre-tension of the bolts and a deterioration in leaktightness. For this reason, most manufacturers of bolt-in manifolds nowadays additionally employ pressure discs. 

Figure 4.99 Adjustment for thermal elongation a - of nozzle b - of manifold...

In the first case, transverse elongation of the manifold has to be taken into consideration in such a way that, when the mould and manifold have been heated, the nozzle and manifold channel are in a coaxial position (see Figure 4.99b). The nozzle position is set when the cavities were positioned, so the user must calculate the size of the manifold from channel axis to mould axis from the formula ... 

In the second case, axial elongation of the manifold, nozzle and spacer pads need to be taken into consideration so that when the mould and HR system are heated, the pretension is attained in the set that does not exceed the admissible surface pressure between pad and clamping plate (this is normally the most loaded place in the set). Figure 4.100a shows diagrammatically an HR system installed without a gap. 

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