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In situ dynamic crystallization properties of industrial soda--lime--silica glasses at realistic processing temperatures have not yet been explored. Hence,we collected in situ high-temperature X-ray diffraction patterns for 10 different industrially manufactured soda--lime--silica glasses as a function of temperature between 900 and 1200°C to investigate the phase relations in their devitrified melts. The high-temperature X-ray diffraction study was complemented by measuring the liquidus temperature of those glasses by the temperature gradient technique. A multiple variable regression analysis was applied to the experimental and modeled data to produce a predictive model for the rate of solidification and liquidus temperature based on glass composition. We have demonstrated that forms of quartz (SiO2) and Na2 CaSiO4, which are not traditionally identified by room temperature X-ray diffraction studies of commercial soda--lime--silica glasses, are the dominant crystalline phases at 800 and 900°C. Upon further heating, different forms of cristobalite become the primary phase field prior to the formation of X-ray amorphous melts, irrespective of the glass composition. Sporadic unidentified as well as high-temperature stable SiO2 polymorphs that are not recoverable to room temperature were also observed. In contrast to the literature, wollastonite (CaSiO3) and devitrite (Na2Ca3Si6O16), which are the main predictor variables in previously developed liquidus temperature models, were not observed prior to the formation of X-ray amorphous glass melts, and hence their influence on liquidus temperature may be questionable. It was also found that the difference between glass processing and liquidus temperatures can be excessively high, and such large temperature differences can potentially be exploited and reduced to enable decreases inmelting or processing temperatures of industrial soda--lime--silica glass melts. [ABSTRACT FROM AUTHOR]

Glasses with high antimicrobial efficacy were developed in the Fe2O3-CuO-P2O5 ternary system to mitigate fomite-mediated transmission of infectious diseases in high-risk settings such as hospitals, daycares, and nursing homes. Binary CuO-P2O5 glasses were not durable enough for use as high touch point articles, so Fe2O3 was added to the compositions to increase the chemical durability. The amount of Cu leachate decreased by at least 3 orders of magnitude when Fe2O3 was increased from 0 to 13.1 mol%. At the highest Fe2O3 contents and corresponding highest durability, the glass was no longer able to pass a test of antimicrobial efficacy with < 3 log kill compared to > 5 log kill for all other compositions. Ab-initio molecular dynamics simulations showed increasing bridging oxygen species at the expense of non-bridging oxygen species with the increase in Fe2O3 content, showing that the glasses exhibited increased chemical durability because they were more interconnected and structurally bound. Experimental results with glasses at fixed CuO and decreasing Fe2O3 confirmed that Fe2O3 content (not CuO) controlled the Cu release rate and, thus, the antimicrobial efficacy of the glasses. The significance of the oxidation state of the leached Cu was overwhelmed by the importance of the amount of Cu leachate. [ABSTRACT FROM AUTHOR]

Based on the current UK decarbonization policy, a general outlook on potential routes for the glass industry to achieve net‐zero is discussed and the differentiation during decarbonization is specified. Biomass ash is considered a potential alternative raw material for low‐carbon glass manufacture as it is rich in certain advantageous components, chiefly network modifiers. Simple sieving processes were shown to effectively separate impurities such as S, Cl, and C from some biomass ashes according to particle size distribution. The concentration of undesirable impurities decreased with increasing particle size. Morphologies and X‐ray diffraction patterns of larger washed biomass ash particles indicated liquid/amorphous phase formation during biomass combustion. The washing of ashes was also shown to be a potential route to purification. A washed bracken ash relevant to both modern and ancient glass production was characterized for comparison. Ultraviolet‐visible near‐infrared (UV‐Vis‐near IR) absorption spectra of representative green container glasses produced using biomass ash confirmed that ∼5 wt.% ash in representative glass batches has little impact on the color and redox state of glasses; the redox status of glass produced using >2 mm biomass ash after washing was less reduced than that of glass produced using high levels (>∼9 wt.%) of >2 mm biomass ash after sieving alone, observed via the redox couple Cr3+/Cr6+ by UV‐Vis‐near IR absorption spectroscopy. [ABSTRACT FROM AUTHOR]

We integrate available and new technologies to strongly enhance student engagement in upper division undergraduate courses on human evolution and history. First, we use peer-mentored discussion groups through the Blackboard system--appropriately scaled, constructed, and incentivized. These allow day-to-day monitoring of student understanding. Second, we use weekly Blackboard e-quizzes directed at important issues or areas of confusion including those revealed by discussion groups. Third, we use a novel digital textbook. This technology provides diverse, sophisticated assets ranging from animations and interactive questions to an extensive glossary hyperlinked to an electronic textbook. The ease of revision of this textbook allows us to react, year to year, to student need and experience. The real power of our approach derives from the extremely strong synergy between these three assets, as we will discuss. We describe successful applications of this model in large (ca. 500) and small (ca 25) classes.