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The crystallization behavior of avobenzone in cosmetic formulations has been investigated with a focus on its interaction with titanium dioxide and zinc oxide particles. Characterization studies using SEM, powder X-ray diffraction (PXRD), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS) reveal that avobenzone undergoes crystallization facilitated by nucleation on the surfaces of these metal oxide grains. The presence of wax and titanium oxide within the crystalline structures further suggests a complex formation, potentially involving catalytic effects on avobenzone nucleation and isomerization. Notably, the addition of ascorbyl palmitate inhibits unwanted crystallization, possibly through competitive complexation with exposed metal ions. These findings underscore the significance of formulation modifications in stabilizing avobenzone against crystallization, ensuring enhanced product stability in cosmetic applications. Future structural studies are anticipated to elucidate the precise nature of these co-crystalline phases, offering insights into optimizing sunscreen formulations for improved performance and longevity. [ABSTRACT FROM AUTHOR]

The paper presented delivers the proof for one of the possible solutions to the so-called medium-temperature gap—the lack of electrolytic systems able to efficiently work in a temperature range spanning from 200 to 450 °C. Regardless of the progress made in this field, the commercially available systems are still operating either at close to ambient temperatures, where hydrogen purity requirements are a significant limit, or above ca. 600 °C, where they suffer from increased corrosion and excessive thermal stresses occurring during startup and shutdown. Alkali metal orthoborates (M3BO3 M = Li, Na, K, or the mixture of these), in contrast to commercially used tetra-(M2B4O7) and meta-(MBO2) borates of these metals, are compounds with relatively poorly understood structure and physicochemical properties. The possibility of their application as an electrolyte in a fuel cell is a relatively new idea and has been preliminary reported. Therefore, an extended phase-focused analysis of the materials applied was needed to re-optimize both the synthetic strategy and the application route. Results of PXRD and FT-IR investigations showed, on the one hand, a complicated multi-phase structure, including the main orthoborate phase, as well as the presence of additional borate-based phases, including boric oxoacid. On the other hand, DTA tests proved not only that their melting temperatures are lower than these characteristics for the tetra- and meta-counterparts, but also that cation mixing leads to a subsequent decrease in this important functional parameter of the materials studied. [ABSTRACT FROM AUTHOR]

In recent years the interest in lead-acid batteries has resurfaced, amidst the rising need for power storage technologies spanning to not just mobile, but also stationary applications. While lithium-ion batteries remain one of the most common power sources in today's western world, due to many concerns regarding various shortcomings of the said technology alternatives are often discussed. There is a push for adapting lead-acid batteries (as part of the advanced lead acid battery initiative) as replacement for the lithium batteries all over the world, the USA included, due mainly to their lower price and reliability in hotter climates. Furthermore - due to the rising need for uninterrupted power delivery systems, new designs of such devices are being developed and implemented in the western world hoping to meet the demands of the market. As a result, new additives to electrode material, as well as battery designs have been developed and are currently being considered for inclusion in the modern lead-acid battery construction. [ABSTRACT FROM AUTHOR]

The introduction of the hydrogen economy, despite its obvious technological problems, creates a need for a significant number of niche-focused solutions, such as small-sized (10–100 W) fuel cells able to run on hydrogen of lesser purity than what is considered a standard in the case of PEMFCs. One of the solutions can be derived from the fact that an increase in the operational temperature of a cell significantly decreases its susceptibility to catalyst poisoning. Electrolytes suitable for the so-called medium temperature operational range of 120–400 °C, hence developed, are neither commercialized nor standardized. Among them, phosphate silicate protonically conductive glasses were found not only to reveal interestingly high levels of operational parameters, but also, to exhibit superior chemical and electrochemical stability over their polymeric counterparts. On the other hand, their mechanical properties, including cracking fragility, still need elaboration. Initial studies of the composite phosphate silicate glasses with uranyl-based protonic conductors, presented here, proved their value both in terms of application in fuel cell systems, and in terms of understanding the mechanism governing the charge transport mechanism in these and similar systems. It was found that whereas systems containing 10–20 wt% of the crystalline additive suffer from significant instability, materials containing 45–80 wt% (with an optimum at 60%) should be examined more thoughtfully. Moreover, the uranyl hydrogen phosphate was found to surpass its arsenate counterpart as an interesting self-healing behavior of the phase structure of the derived composite was proved. [ABSTRACT FROM AUTHOR]

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A biography of diplomat, scholar and Hoover Institution staff member Witold Saturnin Sworakowski is presented. He was born in the Austro-Hungary easternmost province Suceava, Bukovina in 1903. He has studied at the School of Political Sciences in Warsaw, Poland and worked at the Institute for the Study of Nationality Affairs after his graduation in 1933.

An excerpt from the memoir of pianist Helena Paderewska on their carefree celebration in the summer of 1914 is presented.