Relative gain humidity

Relative humidity, percent = 50 Wind velocity, mi/h = 5 Dry-bulb air temperature, °F = 68 Solar heat gain, Btu/(h-ft ) = 100 Water quantity, gal/min = 10,000... 

Specification grade K nitrate gains 0,76% by wt at 70°F and 90% relative humidity Toxicity. Ingestion of large amounts may cause violent irritation of the intestinal lining. Prolonged exposure to small amounts may result in anemia and nephritis. Moderately poisonous on ingestion or inhalation (Refs 9 10)... 

As mentioned previously, the cement contains both tightly bound and loosely bound water. The set cement can both lose and gain water depending on its environment. Under drying conditions (say 50 % relative humidity) it loses water and shrinks. When placed in water there is an... 

This sensitivity to water has practical implications. A cement liquid is stable in an atmosphere of 70 % relative humidity. It will gain water in more humid atmospheres and lose it to drier ones, and this will adversely affect cement properties (Paffenbarger, Schoonover Souder, 1938 Worner Docking, 1958 Wilson et al., 1970a). 

X-ray analysis of the various samples that were produced indicated that the system ZnO-ZnClj-HjO includes four crystalline phases, two of which, ZnO and ZnClj. l HjO, are essentially the starting materials. Sorrell also found the 4 1 5 phase, reported by Droit, with an identical X-ray powder diffraction pattern to that reported by Nowacki Silverman (1961, 1962), and a 1 1 2 phase. Since neither the 1 1 2 nor the 4 1 5 phase lost or gained weight on exposure to air at about 50% relative humidity and 22 °C and no changes developed in the X-ray diffraction pattern following this exposure, he concluded that the previously reported 1 1 1 phase cannot be formulated from mixtures of ZnO and aqueous ZnCl,. 

Fig. 12 Percent weight gain associated with the exposure of tablet formulations to 80% relative humidity at 40°C. Formulation A (0) was essentially a 1 11 blend of the drug entity and microcrystalline cellulose, while formulation B ( ) was essentially 1 5.5 5.5 drug-microcrystalline cellulose-starch.

Aluminum composites. See also Aluminum-filled composites maximum packing fraction of, 70 25-26 spatial charge carriers in, 70 22 weight gain during relative humidity aging, 70 24... 

The minimum bed diameter is a function of the operating velocity, the particle characteristics and the humidity of the drying gas. The hot gas at the inlet rapidly loses heat and gains moisture as it passes through the bed which it eventually leaves at the bed temperature Tb and with a relative humidity which is approximately equal to the relative humidity which would be in equilibrium with the dried product at the bed temperature. The operating velocity may be taken as twice the minimum fluidising velocity, obtained from the equations in Section 6.1.3, by laboratory tests, or more conveniently from Figure 16.26. 

The nails are composed of flattened, keratinized cells, fused into a dense and hard, yet slightly elastic plate. Their thickness varies from 0.5 to 1.0 mm. In contrast to the stratum corneum (10%), the total lipid content of the nails lies between 0.1% and 1%, and the keratin domain is harder, due to higher sulfur content (cystine). Moreover, the water content is only 7% to 12%, in comparison to 25% in the stratum corneum. The relative water gain may not exceed 25% at 100% relative humidity, in sharp contrast to 200-300% as found in the stratum corneum. 

Heat of Formation, +166.3kcal/nole Hygroscopicity at 25°C, gains 0.22% at 100% RH (Relative Humidity)... 

For a food system in equilibrium with a gaseous atmosphere (i.e. no net gain or loss of moisture to or from the system caused by differences in the vapour pressure of water), the equilibrium relative humidity (ERH) is related to aw by ... 

Thus, under ideal conditions, ERH is the % relative humidity of an atmosphere in which a foodstuff may be stored without a net loss or gain of moisture. Water activity, together with temperature and pH, is one of the most important parameters which determine the rates of chemical, biochemical and microbiological changes which occur in foods. However, since aw presupposes equilibrium conditions, its usefulness is limited to foods in which these conditions exist. 

The aw of a sample can also be estimated by exposing it to atmospheres with a range of known and constant relative humidities (RH). Moisture gains or losses to or from the sample may then be determined gravimetri-cally after equilibration. If the weight of the sample remains constant, the RH of the environment is equal to the ERH of the sample. The aw of the food may be estimated by interpolation of data for RH values greater and less than the ERH of the sample. 

The moisture content of the 15 tray-dried batches following final mix remained essentially unchanged from the drying step. The batches from the fluid bed process gained moisture. This is probably attributable to handling very dry material in a relatively humid environment. Both groups are still below the target for this step of 1.5 %, however. 

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