Hygroscopicity Data

Note Dynamic tests conducted in humidity cabinet having complete change of atmosphere every 3 minutes. Surface area to weight ratios of large Petri dish, small Petri dish, and vial were 17.0, 2.4, and 0.25, respectively. 

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Kreidenweis, S. M., Koehler, K., DeMott, P. J., Prenni, A. J., Carrico, C., and Ervens, B. Water activity and activation diameters from hygroscopicity data — Part I Theory and application to inorganic salts, Atmos. Chem. Phys., 5, 1357-1370, 2005, http //www.atmos-chem-phys.net/5/1357/2005/. 

Particle size is a major factor which determines the alpha dose conversion factor for radon daughters (mGy/WLM). Data on indoor environments are emerging and indicate that a variety of specific conditions exist. For example, a dose factor four times that for a nominal occupational or environmental exposure exists if kerosene heater particles dominate the indoor aerosol and four times smaller if a hygroscopic particle dominates. 

The hygroscopicity of the commercial sorbitol samples was investigated with an automated moisture balance system, where the relative humidity (RH) could be varied over the range of 0 to 90% [32], EMC sorption values were calculated from the raw data at each relative humidity and are summarized in Table 5, and moisture uptake curves for the sorbitol... 

The unambiguous characterization of glycosyl esters of nucleoside pyrophosphates is difficult, as no suitable crystalline derivatives are known for them, and the hygroscopic nature of their ammonium and metal salts prevents reliable interpretation of the data of elementary analysis. 

HNF) of 0.90 is too high to formulate a practical HNF-GAP propellant, a (HNF) of 0.75 is chosen. Though and decrease to 274 s and 3160 K, respectively, the superiority of HNF-GAP propellants is evident when the data are compared with those for HNF-HTPB propellants, as are also shown in Figs. 4.20 and 4.21. However, it is important to note that HNF is highly hygroscopic and that its impact sensitivity and friction sensitivity are high compared to those of other crystalline oxidizers. 

Effect of Humidity. Extensive data were not taken hy MSW on the effects of humidity. Instead they chose to control the RH. at approx 40% for all the tests. Since LA is not hygroscopic, no effects due to changes in surface conductivity would be anticipated for himities below 70% and this was shown to be true by the authors of Ref 35. Loeb (Ref I), however, pointed out that impurities in the ambient gas can strongly affect the nature... 

The product is distinguished from nitrocellulose by its higher hygroscopicity and poorer solubility in organic solvents. Data illustrating the point are listed in Tables 102 and 103. 

Simultaneously with Tilley, we studied the hydroboration of diphenyl (vinyl)phosphine with dialkylboranes (Scheme 29). 54,55 The reactions can be conducted in toluene as well as THF, and required a slightly elevated temperature for 9-H-BBN (60 °C) compared to Cy2BH (room temperature). PBs 40e and 40f were obtained in near quantitative yields as extremely hygroscopic white solids. The P-B adducts [(vinyl)Ph2P-BHR2] are likely intermediates in these hydroboration reactions. The 31P and rlB NMR data substantiate monomeric open structures for both 40e and 40f in solution. 

Three 2-substituted tetrazole 1-oxides 550 representing the parent structure 548 (Scheme 163) have been reported (1913G71, 1983BAU181, 1984BAU142) (Scheme 165). These N-oxides are hygroscopic and crystallization with 0.5 mol of water has been observed. IR and H NMR data have been reported (1984BAU142). 

Wu-Pong and Byron [15] have contributed a review of the issues associated with pulmonary delivery of ASOs. Since ASOs are freely soluble and highly hygroscopic, it would be reasonable to assume that initial dosage forms will rely upon the aerosolization of simple aqueous solutions. Our data indicate that commercially available nebulization devices will generate suitable aerosolizations of ASO solutions at concentrations up to 180 mg/mL [3]. Ultrasonic and jet nebulizations were found to have essentially no effect on the phosphorothioate stability of the ASO over 40 min, which is longer than typical treatment times. 

Be(N03)2 is a white, hygroscopic solid. The bonding between the metal and the nitrate group is covalent. On being heated above 125°C it rapidly loses N02 with the formation of the oxide nitrate Be40(N03)6.24 Obviously, for that reason, there are no high-temperature thermodynamic data. Data at 298.15 K are shown in Table 5.13. 

Different types of evidence exist for the clinical efficacy of 10% urea in the treatment of psoriasis (Table 19.1). Early clinical data from a clinical study on various types of hyperkeratosis showed no superior effects on from 10% urea cream compared to ordinary aqueous cream BP in the treatment of psoriasis.10 However, five psoriatic patients with chronic therapy-resistant lesions obtained soft and pliable skin after treatment with 10% urea, but no effect on erythema was observed.17 Psoriatic lesions on the extremities (at least 5 cm in diameter in size) also showed clinical improvement after two weeks of treatment with an ointment containing 10% urea (Basodexan S ointment) in a placebo-controlled study on ten patients.26 Higher values of skin capacitance (suggested to reflect skin hydration) were also noted on urea-treated areas. Increased hygroscopicity and water content were also obtained after treatment with 10% urea ointment in patients with psoriasis vulgaris.27 Moreover, urea treatment reduced epidermal proliferation, measured as an altered expression of involucrin and cytokeratins.26 Treatment of psoriasis vulgaris with 10% urea-formulations support clinical efficacy at evidence-level lb (cf. Figure 19.1). 

Hydroxyquinolino)antimony(V) choride has been obtained as a orange colour hygroscopic monomeric non-electrolyte solid by the reaction of antimony(V) chloride and 8-hydroxyquinoline in CCV84. On the basis of UV, IR and H NMR data, an hexacoor-dinated geometry has been suggested. 

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