Mie effect

As the temperature of a nucleic acid solution is raised, and the H bonds between the bases are broken, single strands are formed and there is an inerease in the ultra-violet absorption (hyperchro-mie effect) (Figure 10.46). For DNA this occurs over a eomparatively narrow range of temperature. 

MIE-STD-1629 (SHIPS), Proceduresfor Performing a Eailure Mode and Effects Mnalysisfor Shipboard Equipment, Department of the Navy, Naval Ship Engineering Center, HyattsviUe, Md., 1974. 

Spectroscopic examination of light scattered from a monochromatic probe beam reveals the expected Rayleigh, Mie, and/or Tyndall elastic scattering at unchanged frequency, and other weak frequencies arising from the Raman effect. Both types of scattering have appHcations to analysis. 

FIQURE 3-5.4.1 Effect of electrode diameter and circuit capacitance on MIE of hydrogen in... 

FIQURE 5-1.4b. Effect of pressure on MIE of propane in uarious oxygen-nitrogen mixtures. 

FIQURE 5-1.4.4. Schematic effect of droplet diameter on MIE of typical petroleum products. 

The maximum effective energy of a static discharge can be compared with the MIE of a dust to determine whether ignition is probable, as discussed in Chapters 2 and 3. MIE test methods are described in S-5.4.2 and special considerations discussed in 6-1.3 through 6-1.5. At the time of writing, ASTM was close to development of a standard for dust MIE measurement. 

In addition to the great dependence of MIE on particle size distribution and the possible accumulation of additives, complicating factors in measuring and applying MIE data include the presence of flammable gas (6-1.3.1) plus the effects of moisture (6-1.6) and possibly increased temperature (6-1.5) relative to the test temperature. 

Eor example, a dust with MIE of 1000 mJ at 20°C has a predicted MIE of 21 mJ at r = 100°C. Based on the test results reviewed in [59] the effect of temperature on powder MIE might be major and should always be considered where powder is heated. 

This approach has not been tested for any dusts that bum heterogeneously such as some metal dusts (A-6-1.2). Also, this large an effect of temperature has not been found by some other workers, it has yet to be confirmed that the effect is not due in part to loss of moisture (6-1.6) or evolution of flammable gas (6-1.3), both of which can have large effects on MIE. 

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