Chamber effects

NOTE Animals were injected 10 minutes before being placed in the chambers. Effects of selected doses are shown as group means SEM... 

Chanton, J.P., Whiting, GL. Showers, W.J., and Crill, P.M. (1992) Methane flux from Petulandra virginica stable isotope tracing and chamber effects. Global Biogeochem. Cycles 6, 15-31. 

The ICP-AES and ICP-MS techniques may also suffer from matrix effects, such as spray chamber effects caused by the different viscosity of the samples and the calibration standards. The careful choice of internal standards can reduce this problem. The effects caused by high amounts of easily ionized elements may be solved by internal standardization or by the use of matrix-matched calibration curves. An additional specific problem with ICP-AES is the risk of spectral overlaps. 

Maren TH. The rates of movement of Na+, CU, and HCOj" from plasma to posterior chamber effect of acetazolamide and relation to treatment of glaucoma. Invest Ophthalmol 1976 15 356-364. 

Note that the characterization runs were modelled using the default charaeterization parameters used when modelling the mechanism evaluation runs, not with the values that were adjusted to fit the individual experiments. Therefore, the relatively large variability and average model error for the model simulations of A([03]-[N0]) in those experiments provides a measure of the variability of the chamber effects parameters (e.g., HONO offgasing) to which these experiments are sensitive. The relatively low average bias is expeeted because the chamber effects parameter values were derived based on these data. 

For the single VOC - NOx or VOC - CO - NOx experiments, the model is able to simulate the A([03]-[N0]) to within 25% or better in most cases, which is better than the 30% seen in previous mechanism evaluations with the older chamber data (Carter and Lurmann, 1990, 1991 Gery et al., 1989, Carter, 2000). However, there are indications of non-negligible biases in model simulations of certain classes of experiments. The cleaner conditions and the relatively lower magnitude of the chamber effects may make the nm-to-run scatter in the model performance may be less than in the simulations of the previous data, and this tends to make relatively small biases in the model performance more evident. There are, for example, definite biases in the model to under predict O3 formation and NO oxidation in the surrogate - NOx experiments carried out at lower ROG/NOx ratios. These cases are discussed further elsewhere (Carter, 2004b). 

Figure 4. Plots of the mechanism under prediction bias for model simulations UCR EPA ambient surrogate - NOx experiments against normalized ROG/NOx ratios for the SAPRC-99 and Carbon Bond mechanisms. The SAPRC-99 calculations show effects of varying the MONO offgasing chamber effect parameters and using a lower OH + NO2 rate constant.

Figure 4 shows the effects of using different mechanisms or mechanism parameters on plots of the under prediction bias the UCR EPA ambient surrogate experiments. The filled diamonds show the same results as shown on Figure 3 for this chamber, and the error bars show the effects of varying the HONO offgasing chamber effect parameter from zero to the... 

A database for mechanism evaluation is therefore not complete without reeommendations for appropriate inputs to auxiliary mechanisms. Such chamber effects models have aheady been developed for the SAPRC chambers as part of the process of evaluating SAPRC-99 and related mechanisms (e.g. Carter, 2000), and these form the basis of the auxiliary mechanisms applied in the present study. 

Manas, P., Barsotti, L., and Cheftel, J.C. 2001. Microbial inactivation by pulsed electric fields in a batch treatment chamber Effect of some electrical parameters and food constituents. Innovative Eood Science and Emerging Technologies 2 239-249. 

Bombardier beetles. Beetles of the genus Brachinus and related species. They possess an abdominal defensive gland with which they can shoot explosion-like a hot secretion at an enemy. For this a 25% HjOj solution and a 10% solution of hydroquinone are injected into a combustion chamber . The catalases and polyphenol oxidases (temperature optimum of the enzymes 70-80 °C) present in the chamber effect an explosive reaction to water and benzoquinone or methyl-1,4-benzoquinone and the up to 70 °C hot mixture is shot speciflcally at the enemy. 

At what power range Is the Integrating Ionization chamber effective ... 

Fig. 8-23. High-level gamma ionization chamber. Effective volume, 120 cm electrode spacing, 1/8 in. performance, 20 /la, chamber saturated at 100 volts at radiation level of 3 X 10 r/hr design temperature, 130°F.

CLOUD CHAMBER EFFECT. The cloud chamber effect refers to a mist of tiny water droplets or condensation cloud that is temporarily formed around the fireball generated by a nuclear weapon explosion. This effect is produced by the expansion of air in the negative-pressure phase of the blast wave (a nuclear detonation produces a negative-pressure phase, followed by a positive-pressure phase, which is experienced as the shock wave). The drop in pressure brings about an equivalent drop in temperature, and as a consequence, any water vapor present condenses. See also BHANGMETER. 

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