Maximum release

A key parameter in the design of the fuel vapor control system is the volume of activated carbon required to meet the emission standards for the various regulatory tests. In the case of the three-day diurnal test sequence, the emission limits are 0.05 grams of HC per mile during the run loss portion of the test (maximum emission -0.85 grams), and a maximum release of 2.0 grams for the sum of the hot soak period and any one of the three 24-hour periods making up the diurnal test sequence. 

The value of Cs is the most critical parameter in determining the overall release rate from a given osmotic system. Indeed, its value will determine whether or not it is feasible to utilize an osmotic system to deliver a particular drug for a specified duration. The maximum release rate achievable is likely that seen with KC1. The relevant values for the parameters in Eq. (6) for OROS [10] are as follows A = 2.2 cm2, h = 0.025 cm, LpO = 2.8 X 10 6 cm2/(atm hr), Us = 245 atm, and Cs = 330 mg/mL. This translates to about 20 mg/hr or about 250 mg over a 24 hr period. This is for a highly water soluble drug with a high osmotic pressure differential. For drugs of moderate solubility—for example,... 

In vitro release data of propranolol hydrochloride from the four formulations evaluated ovr a 24 h period are shown in Table 2. The decreasing rank order of drug release from these samples was observed to be as follows Methocel matrix> Avicel CL-611 matrix>PVA-gelatin matrix>emulsion base. The Methocel matrix, formulation A, exhibited the maximum release of the drug, whereas the drug released was at a minimum from the PVA-gelatin matrix, formulation... 

In considering the operational safety and accident analyses of sodium-cooled fast reactors, similar information on the release of fission products from sodium is needed. Although the extent of vaporization can often be calculated from thermodynamic considerations (3, 4), appropriate transport models are required to describe the rate phenomena. In this chapter the results of an analytical and experimental investigation of cesium transport from sodium into flowing inert gases are presented. The limiting case of maximum release is also considered. 

Maximum Release. The analytical model described above assumes that the liquid phase is completely stagnant. While this may be true in an ideal laboratory experiment where a small sample can be kept isothermal at a specified temperature, in large scale systems where non-isothermal conditions exist, both natural convection and molecular diffusion will contribute to mass transfer. This combined effect, which is often very difficult to assess quantitatively, will result in an increase in fission-product release rate. Therefore, in making reactor safety analyses, it is desirable to be able to estimate the maximum release under all possible conditions. 

In considering the case of maximum release, it is apparent that complete mixing in the liquid phase will lead to a greater release rate than that expected in cases where diffusion operates in two phases. Therefore, consider the case where both the solvent (Na) and the solute (volatile fission product) diffuse through a gas layer of constant thickness. It follows from the solution to Fick s law with appropriate boundary conditions that... 

Releases from enclosures are either scrubbed before being released to the atmosphere, vented to a safe location, or routed to a flare system. In all cases, when determining the size and type of vent, maximum release rates and back-pressures while venting should be calculated. An airtight enclosure could structurally fail because of a pressure buildup from liquid vaporization if it is not properly vented during a release (Harris, 1991). 

During thermal treatment, a-Mg(BH4)2 first undergoes a phase transformation at about 190 °C before it further decomposes in several steps to MgH2, Mg, and MgB2 (Eqs. (5.10) and (5.11)) [33]. The weight loss between 290 and 500 °C is 13 wt.% H2 with a maximum release between 300 and 400 °C. Small amounts of B2H6 were detected by mass spectrometric measurements. The presence of TiCl3 decreases the... 

A wide range of vehicles can be used in iontophoretic drug delivery, giving consideration to drug solubility in the donor delivery site, protection of the skin from irritation or bums, and the maximum release of drug. 

Labeled. Seed 3 x 10 cells/well/3 ml of serum-free DMEM and incubate at 37°C for 70 h. Cells usually attach within 2 h. Take aliquots of medium from the upper compartments at 2, 22, 46 and 70 h of incubation mix with 5-10 ml of suitable solution and measure in the scintillation counter. After 70 h take a sample also from the lower compartment and count. Incubate control wells for 12 h at 37°C with 2 ml of 0.1% of bacterial collagenase (BC) dissolved in 0.5 M Tris-HCl, 50 mM CaCla, 0.2 M NaCl, pH 7.4. Express the results as percentage of maximum release (BC) of collagen-incorporated radioactivity (Russo et al., 1986). 

Lysis = (release in assay - spontaneous release)/ (maximum release - spontaneous release)xlOO. 

When the major alkaloid in tobacco samples is nor-nicotine, the commonly used steam-distillation method and automated procedures result in poor estimates of nicotine and nornicotine. Rosa18 therefore developed a pyrolysis-gas chromatographic method, whereby pyrolysis was carried out with a Victoreen pyrolyzer fitted to the gas chromatograph. Nicotine is relatively volatile and readily released by pyrolysis, even at 100°C. Nornicotine, being less volatile, showed maximum release by pyrolysis at 300°C. The pyrolysis-gas chromatography was carried out with ca. 1 mg of tobacco. The results obtained with the method are presented in Figure 5.3. 

In situ measurements of Mn fluxes with benthic chambers and dialysis samplers confirmed the seasonal variability of the Mn redox cycle. They indicated that the reduction of particulate Mn oxides is a fast process that occurs close to the sediment surface within a time scale similar to that of Mn(II) oxidation. A maximum release rate of 5.5 mmol/m2 per day was measured in July. This rate indicates a close coupling between the oxidation of Mn(II) in the bottom waters and the reduction of Mn02 at the sediment surface. 

The thermal decomposition of ammonium uranate in flowing hydrogen has been shown to be accompanied by an initial decrease in the surface area of the pellets as the temperature was increased to 100 °C, but thereafter to be accompanied by an increase in the surface area as dehydration occurred. A sudden increase in the surface area at 325 °C was reported to be associated with nitrate decomposition. No significant evolution of ammonia was recorded below 190°C the maximum release of ammonia occurred at 330 °C with decomposition of the ammonium uranate. At 300 °C the predominant phases were identified as ammonium uranate and U03,2H20 with very minor amounts of P-UO3. At 350 °C complete disruption of the ammonium uranate lattice was observed. 

A material transported in a specially designed confainer to minimize the likelihood of a release based on safety concerns (accidental release) may have ranked low as having a potential for a large release. However, since the goal of an intentional act is to create a maximum release, a larger security event may be possible than that anticipated from an accidental scenario. 

The concentrations of suspended particle matter (SPM) near bottom waters at stations B1 and E3 were 9.6 14.2 and 19.3 24.0 mg/L with averages of 12.2 and 22.2 mg/L, respectively. The reciprocal of the SPM near bottom waters was 0.08 L/g at station B1 and 0.045 L/g at station E3. The annual variation of SPM between the BH98 and BH99 cruises was 25% and 11% at stations B1 and E3, respectively. This implied that the nutrient releases from sediments could be very close to the maximum release. In the experiment, the atom ratios of released nutrients were Si DIN P=40 25 l, which indicated that the phosphorus amount was relatively low compared to the Redfield ratio (Si N P 16 16 l). Fig. 2.45 (Liu et al., 2004) is the plot of time dependent desorption/release of phosphate and silicate from sediments. When surface sediment and seawater were mixed, they were released from sediments (Fig. 

---