Exposure interval

The exposure interval for the bed, T, is inversely proportional to the kiln rotation rate. Hence, equation 21 shows that the time constant for desorption is directly proportional to the bed depth and inversely proportional to the square root of the kiln rotation rate. However, the overriding factor affecting is the isotherm constant iC which in general decreases exponentially with increasing temperature as in equation 4. 

The acceptable operator exposure level (AOEL) for each route of exposure is assigned from the no effect level (NOEL) in a specific toxicity test multiplied by a safety factor. The value for samples containing no detectable residues is assumed to be one half the limit of detection. For cyromazine, the seasonal use pattern indicates that the exposure is most comparable to the 21-day dermal exposure interval, and a value of 2000 mg/kg bw/day was taken as the dermal AOEL. The inhalation AOEL was obtained from a 28-day inhalation study with rats. As cyromazine is not a carcinogen, the safety margin used for calculation of the of the results using the EEC method... 

If a signal is varying during exposure, the value obtained after division is exactly what we need the time-average over the exposure interval. 

There is a shortest reasonable exposure time that is related to the frequency of the heartbeat quartz and the adjustment of the voltage-to-frequency converters. Below the reasonable exposure interval quantization errors become a problem and the measured value will be chosen from a small number of possible steps. 

The primary beam profile is reasonably measured during adjustment of the optics just before the beam stop is inserted. If overexposure of the detector can be avoided by choosing a short exposure interval this method is to be favored. Instead, attenuation of the primary beam by an absorber must be considered. 

Lethal concentrations (LC) of cadmium to freshwater biota during various exposure intervals... 

Table 1.3 Lethal Concentrations (LC) of Cadmium to Freshwater Biota during Various Exposure Intervals (Concentrations shown are in pg Cd/L (ppb) of medium fatal to 10% or 50% of test organisms)... 

Group, Taxon, or Life State Water Hardness, (mg CaC03/L) LC Values, (pg/L) Exposure Interval Reference9... 

Route of Administration (units), Organism, and Mercury Formulation Concentration Exposure Interval Effect Ref ... 

Organism Dosea Exposure Interval (days exposure/ postexposure) Mortality (%) Reference11... 

Organism Mirex Dietary Concentration (mg/kg ration) Exposure Interval Percent Mortality Reference ... 

Medium, Taxonomic Group, and Species Exposure Interval (hours [h], days [d], or life cycle [LC]) LC50 (pg/L) Reference1... 

Acute, for example, implies a single exposure interval (of 24 h or less) or dose of test material. Using the second scheme (length of dosing), the objectives of the successive sets of pivotal studies could be defined as follows ... 

Data concerning the xenon arc exposure of PECT have been reported [2], Note that comparison is made to general purpose polycarbonate and impact modified acrylic for the color development. The PECT copolymer obviously changes much more rapidly in b value [3] than either of these materials. Flatwise impact testing (see below) showed the PECT sample to be ductile at the test start and brittle at the first exposure interval of 800kJ/m2 exposure. 

Figure 16.27 shows the result of observing the movement of a euglcna cell s tail. The cell was exposed three times in order to observe its sequential movements. Each exposure time was 50 ms, and the exposure interval was 500 ms. 

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