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High-temperature X-ray diffraction with concurrent gas chromatography (GC) was employed in the study of iron disulfide (FeS2) cathode pellets disassembled from thermal batteries. When FeS2cathode materials were analyzed in an air environment, reaction of the KCl and LiCl salt phases led to the formation of Li2(SO4) and KFe2S3phases beginning at ~230 °C. These phases subsequently reacted to generate various forms of potassium iron sulfates in the 280–500 °C range, with the final products resulting in a β-Fe2O3phase and K2(SO4). Independent simultaneous thermal analysis coupled with mass spectroscopy (MS) augmented the diffraction results and supported the overall picture of FeS2decomposition. Both gas analysis measurements (i.e. GC and MS) from the independent experiments confirmed the formation of SO2off-gas species during the breakdown of the FeS2. In contrast, characterization of the same cathode material under inert conditions showed the persistence of the initial FeS2phase throughout the entire temperature range of analysis.

The systematic development of microstructure, solidification characteristics, and heat of solidification with composition in copper-silicon-magnesium alloys for thermal energy storage is presented. Differential scanning calorimetry was used to relate the thermal characteristics to microstructural development in the investigated alloys and clarifies the location of one of the terminal three-phase eutectics. Repeated thermal cycling highlights the thermal storage stability of the transformation through multiple melting events. Two near-terminal eutectic alloys display high enthalpies of solidification, relatively narrow melting ranges, and stable transformation hysteresis behaviors suited to thermal energy storage.

Magnesium bis-o-cresol (or o-methylphenoxide), [Mg(oMP)2]n (1), was prepared through a variety of synthetic routes that involved the stoichiometric reaction of o-methylphenol (H-oMP), with Mg(Bu)2, Mg{N(Si(CH3)3)2}2(THF)2, or the bulk metal (Mg⁰). In all cases the low-temperature product was found to be soluble, while precipitation occurred at higher temperatures. The precipitate could only be redissolved by the addition of pyridine or a similarly strongly coordinating Lewis base. The pyridine and NH3 adducts of 1 were isolated as monomeric species, whereas the THF adduct proved to be the dimeric [Mg(μ-oMP)(oMP)(THF)2]2, 2. For a limited set of conditions, sufficient control over the precipitation kinetics of the reaction between Mg(Bu)2 and H-oMP was realized to yield spherical morphologies. The window of spherulitic growth was small and could only be partially controlled by varying reaction conditions during the precipitation. Use of seed particles to control nucleation events during precipitation was found to lead to increased monodispersity of spherical [Mg(oMP)2]n precipitate powders.

Differential enthalpies of adsorption (ΔHads) of benzene, ethylbenzene, and 1,3- and 1,4-diethylbenzene onto zeolite H-Y at 323 K were measured as a function of sorbate coverage using a microcalorimeter of the Tian−Calvet type. The ΔHads values which correspond to interaction with acidic Brønsted sites varied between the various probe molecules in the range 66 to 125 kJ mol^-1 (neglecting the initial high enthalpies) and increased in the following order:  benzene < ethylbenzene < 1,4-diethylbenzene ≈ 1,3-diethylbenzene. Benzene exhibited a constant ΔHads over a wide range of sorbate loadings, while the substituted benzenes showed gradual increases in ΔHads with coverage, indicating mutual interaction between sorbate molecules. The total number of molecules which were adsorbed per unit mass of zeolite varied inversely with the size of the sorbate molecule, in accordance with volumetric limitations. High values of ΔHads were evolved on sorbing the first few molecules of any of the sorbates per unit cell, due to the interaction between the sorbate and small numbers of residual Na⁺ cations in the zeolite. The differential heats of adsorption of 1,4-diethylbenzene onto dehydroxylated H-Y, as well as partially sodium-exchanged H-Y, were measured for comparison.

As a part of a program to screen and immunize as many Alaska Natives as possible against hepatitis B infection, hepatitis B virus seromarkers were measured in 52,022 Alaska Natives between 1983 and 1987. Hepatitis B surface antigen (HBsAg) was found in 1,603 persons (3.1%), and 7,155 persons (13.8%) exhibited hepatitis B virus seropositivity. While the prevalence of total seropositivity increased with increasing age (p < 0.001), the proportion of seropositive persons who were also positive for HBsAg was significantly higher in children under age 5 years than in persons over age 60 (p < 0.001). The total hepatitis B virus seropositivity was significantly higher in males than in females (p < 0.001), and a greater proportion of seropositive males than seropositive females had HBsAg (p < 0.001). The prevalence of HBsAg and total seropositivity differed significantly by geographic region (p < 0.001), ranging from 0.5% to 8.2% for presence of HBsAg and from 5.4% to 29% for total seropositivity. Of persons who were HBsAg positive, hepatitis B e antigen was found in 35.4%, and antibody to hepatitis e antigen was found in 49.6%. The prevalence of hepatitis B e antigen significantly decreased with age, while that of antibody to hepatitis e antigen significantly increased. The prevalence of hepatitis B virus seropositivity is high in Alaska Natives, and there are significant differences in both the prevalence of HBsAg and total hepatitis B virus seromarkers by age, sex, and geographic region.

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