Finite delays

The autoignition temperature (AIT) or tlte maximum spontaneous ignition temperature is defined as the maximum temperature at which combustion occurs in a combustible bulk gas mixture when tlie temperature of a flammable gas-air mixture is raised in a uniformly heated apparatus. The AIT represents a tlircshold below which chemicals and combustibles can be handled s ely. (The AlTs of selected substances arc available in the literature. ) The AIT is strongly independent on tlie nature of hot surfaces. The AIT may be reduced by as mudi as 100-200°C when the surfaces arc contaminated by dust. When tlie temperature of a flanuiiable mi.xturc is raised to or above the autoignition temperature, ignition is not spontaneous. Most notably in liquids, there is a finite delay before ignition lakes place, i.e., a lapse between the time tlicrc is a flammable mixture reaches its flame temperature and tlie first appearance of a flame. An equation tliat correlates with the ignition temperature is also available in the literature. ... 

Instead, the lyrics about space and its traveling by the finite, delayed light (propagated with the speed of light) are brilliantly embodied by the dammed poet Mihai Eminescu (1850-1889) in the mythical poem Toward the star/ Ad Astra (La Steaua, in Romanian) (Romanian Voiee, 2012), written in 1886 ( ) long before the formulation of postulates of special relativity theory by Einstein, in 1905 ... 

The amplitude and phase curves obtained with the SS316 holder are distorted by the random peaks caused by the spurious resonances (Fig. 18.3c,e). On the contrary, such peaks are suppressed in the curves obtained with the PEEK holder (Fig. 18.3d,f). While the amplitude curve obtained by the PEEK holder shows almost an ideal response, the phase curve deviates from the ideal response. This is because of the linear phase delay caused by the finite delay time required for the deformation of the flexure hinge. However,... 

Phosphorescence methods have fewer applications than fluorescence. Since sample molecules may show both fluorescence and phosphorescence, it is necessary to measure the slower phosphorescence by introducing a finite delay between excitation and measurement. This is done using a shutter system. 

The temperature of the gas in the hot leg piping may have to have been monitored to supply feedback for reactor control. It was desired that the sensors making tlus measurement be as non-invasive as possible in order to minimize flow disraptions and discontinuities in the pressure boundary. The inherent response times of all sensors which were under consideration for measuring the coolant are on the order of several milliseconds. Placing them outside the gas stream would have introduced a finite delay time for the temperature at the sensor location to reach equilibrium during a transient. This delay time would have depended primarily on the heat transfer properties of the piping configuration and would dominate the response time of the hot leg temperature sensor. 

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