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Dissolution Rates Of Borophosphate Glasses In Deionized Water And In Simulated Body Fluid, Parker T. Freudenberger, Rebekah L. Blatt, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

Particles of Borophosphate Glasses with the Nominal Molar Compositions 16Na₂O-(24-Y)CaO-YSrO-XB₂O₃-(60-X)P₂O₅ (Mol%), Where 0 ≤ X ≤ 60 and Y = 0, 12, and 24, Were Reacted in Deionized Water and in Simulated Body Fluid (SBF) at 37 °C. for the Dissolution Experiments in Water, the PH of the Solution at the Conclusion of the Experiments Increased Systematically, from 2.1 to 9.5, for Y = 0 Glasses When 'x' Increased from 0 to 60. the Reaction Rates over the First 8–24 H of Dissolution in Both SBF and Deionized Water Followed Linear …

Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

Borophosphate glasses were prepared with the nominal molar compositions 16Na₂O-(24-y)CaO-ySrO-xB₂O₃-(60-x)P₂O₅ (mol%), where 0≤x≤60 and y=0, 12, and 24. Information about the compositional dependence of borate and phosphate site speciation and next nearest neighbor linkages was obtained by ¹¹B and ³¹P MAS NMR and Raman spectroscopies, and by high pressure liquid chromatography (HPLC). With the initial replacement of P₂O₅ by B₂O₃, tetrahedral borate sites linked to four phosphate anions, B(ØP)₄, are created in the glass structure, and the average phosphate anion …

Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

Borophosphate glasses were prepared with the nominal molar compositions 16Na2O-(24-y)CaO-ySrO-xB2O3-(60-x)P2O5 (mol%), where 0≤x≤60 and y=0, 12, and 24. Information about the compositional dependence of borate and phosphate site speciation and next nearest neighbor linkages was obtained by 11B and 31P MAS NMR and Raman spectroscopies, and by high pressure liquid chromatography (HPLC). With the initial replacement of P2O5 by B2O3, tetrahedral borate sites linked to four phosphate anions, B(ØP)4, are created in the glass structure, and the average phosphate anion becomes smaller as bridging PØP bonds are replaced by bridging PØB bonds. With further increases in the B2O3 content, borate …

Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow

Mathematics and Statistics Faculty Research & Creative Works

Borophosphate glasses were prepared with the nominal molar compositions 16Na2O-(24-y)CaO-ySrO-xB2O3-(60-x)P2O5 (mol%), where 0≤x≤60 and y=0, 12, and 24. Information about the compositional dependence of borate and phosphate site speciation and next nearest neighbor linkages was obtained by 11B and 31P MAS NMR and Raman spectroscopies, and by high pressure liquid chromatography (HPLC). With the initial replacement of P2O5 by B2O3, tetrahedral borate sites linked to four phosphate anions, B(ØP)4, are created in the glass structure, and the average phosphate anion becomes smaller as bridging PØP bonds are replaced by bridging PØB bonds. With further increases in the B2O3 content, borate …

A Most Unusual Day, Dakota Kraft

Diverse Families Bookshelf Lesson Plans and Activities

The students will ask and answer such questions as who, where, when, why and how to demonstrate understanding of key details in the text. ● The students will describe how characters in A Most Unusual Day respond to major events and challenges. ● The students will use information gained from illustrations and words in a print or digital text to demonstrate understanding of its characters, setting, or plot. ● The student will participate in collaborative conversations about family, family that is biological and family that is not.

Atomistic Modeling Of Heat Treatment Processes For Tuning The Mechanical Properties Of Disordered Solids, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

We investigate the effect of a single heat treatment cycle on the potential energy states and mechanical properties of metallic glasses using molecular dynamics simulations. We consider the three-dimensional binary mixture, which was initially cooled with a computationally slow rate from the liquid state to the solid phase at a temperature well below the glass transition. It was found that a cycle of heating and cooling can relocate the glass to either rejuvenated or relaxed states, depending on the maximum temperature and the loading period. Thus, the lowest potential energy is attained after a cycle with the maximum temperature slightly …

The Influence Of Complex Thermal Treatment On Mechanical Properties Of Amorphous Materials, Nikolai V. Priezjev, Qing-Long Liu

Mechanical and Materials Engineering Faculty Publications

We study the effect of periodic, spatially uniform temperature variation on mechanical properties and structural relaxation of amorphous alloys using molecular dynamics simulations. The disordered material is modeled via a non-additive binary mixture, which is annealed from the liquid to the glassy state with various cooling rates and then either aged at constant temperature or subjected to thermal treatment. We found that in comparison to aged samples, thermal cycling with respect to a reference temperature of approximately half the glass transition temperature leads to more relaxed states with lower levels of potential energy. The largest energy decrease was observed for …

The Effect Of Cryogenic Thermal Cycling On Aging, Rejuvenation, And Mechanical Properties Of Metallic Glasses, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The structural relaxation, potential energy states, and mechanical properties of a model glass subjected to thermal cycling are investigated using molecular dynamics simulations. We study a non-additive binary mixture which is annealed with different cooling rates from the liquid phase to a low temperature well below the glass transition. The thermal treatment is applied by repeatedly heating and cooling the system at constant pressure, thus temporarily inducing internal stresses upon thermal expansion. We find that poorly annealed glasses are relocated to progressively lower levels of potential energy over consecutive cycles, whereas well annealed glasses can be rejuvenated at sufficiently large …

Slow Relaxation Dynamics In Binary Glasses During Stress-Controlled, Tension-Compression Cyclic Loading, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The effect of cyclic loading on relaxation dynamics and mechanical properties of metallic glasses is studied using molecular dynamics simulations. We consider the Kob-Andersen three-dimensional binary mixture rapidly cooled across the glass transition and subjected to thousands of tension-compression cycles in the elastic range. It was found that during cyclic loading at constant pressure, the system is relocated to progressively lower levels of the potential energy, thus promoting greater densification and higher strength. Furthermore, with increasing stress amplitude, the average glass density increases and the minimum of the potential energy becomes deeper, while the elastic modulus is reduced. The typical …

The Yielding Transition In Periodically Sheared Binary Glasses At Finite Temperature, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

Non-equilibrium molecular dynamics simulations are performed to investigate the dynamic behavior of three-dimensional binary glasses prepared via an instantaneous quench across the glass transition. We found that with increasing strain amplitude up to a critical value, the potential energy approaches lower minima in steady state, whereas the amplitude of shear stress oscillations becomes larger. Below the yielding transition, the storage modulus dominates the mechanical response, and the gradual decay of the potential energy over consecutive cycles is accompanied by reduction in size of transient clusters of atoms with large nonaffine displacements. In contrast, above the yield strain, the loss modulus …

Aftershocks In Slowly Compressed Bulk Metallic Glasses: Experiments And Theory, Louis W. Mcfaul, Wendelin Wright, Xiaojun Gu, Jonathan T. Uhl, Karin A. Dahmen

Faculty Journal Articles

We observe two distinct interevent time patterns in the slip avalanches of compressed bulk metallic glasses (BMGs). Small slip avalanches cluster together in time, but large slip avalanches recur roughly periodically. We compare the timing patterns of BMG slip avalanches with timing patterns of earthquakes and with the predictions of a mean-field model. The time clustering of small avalanches is similar to the known time clustering of earthquake foreshocks and aftershocks.

“66 Year Old Bodybuilder William Reed Sees Color For The First Time”, Kaylee Dudley

USU Student Folklore Fieldwork

https://www.youtube.com/watch?v=hqHlIRZnF38

The video opens with a man, William Reed, standing on his porch and the people around him singing happy birthday. He jokes about his age and then talks about guessing what the present might be. There are voices off camera saying, “Don’t guess,” and “You’re gonna guess wrong.” He replies, “Really?” Then begins unwrapping the present. He removes a box from a brightly colored bag filled with tissue paper. He then struggles to open the box because of the packing tape. Someone teases him for taking a while, “You’re just slow cause of your age.” The group laughs and …

“Piper Can See! Original Video!”, Kaylee Dudley

USU Student Folklore Fieldwork

https://www.youtube.com/watch?v=DA0UpPeUAto

The video opens with Piper and in a highchair at a restaurant. Piper is chewing on a paper coaster when her mom begins putting the glasses onto Piper. While still holding the coaster Piper struggles against her mom’s attempts bring her hands up to either side of her face and swaying away. Her mom gets the pink frames on pretty quickly though and says, “Hi!” to Piper in a high voice. “Hi Piper,” she says again. Piper smiles a big smile then looks over at the camera. “How are you?” mom asks and with this Piper smiles even wider …

40ar/39ar Ages Of Lunar Impact Glasses: Relationships Among Ar Diffusivity, Chemical Composition, Shape, And Size, John W. Delano Phd, Nicolle Zellner

Atmospheric and Environmental Science Faculty Scholarship

Lunar impact glasses, which are quenched melts produced during cratering events on the Moon, have the potential to providenot only compositional information about both the local and regional geology of the Moon but also information about the impact flux over time. We present in this paper the results of 73 new 40Ar/39Ar analyses of well-characterized, inclusion-free lunar impact glasses and demonstrate that size, shape, chemical composition, fraction of radiogenic 40Ar retained, and cosmic ray exposure (CRE) ages are important for 40Ar/39Ar investigations of these samples. Specifically, analyses of lunar impact glasses from the Apollo 14, 16, and 17 landing sites …

Reversing The Trend Of Large Scale And Centralization In Manufacturing: The Case Of Distributed Manufacturing Of Customizable 3-D-Printable Self-Adjustable Glasses, Jephias Gwamuri, Ben T. Wittbrodt, Nick C. Anzalone, Joshua M. Pearce

Department of Materials Science and Engineering Publications

Although the trend in manufacturing has been towards centralization to leverage economies of scale, the recent rapid technical development of open-source 3-D printers enables low-cost distributed bespoke production. This paper explores the potential advantages of a distributed manufacturing model of high-value products by investigating the application of 3-D printing to self-refraction eyeglasses. A series of parametric 3-D printable designs is developed, fabricated and tested to overcome limitations identified with mass-manufactured self-correcting eyeglasses designed for the developing world's poor. By utilizing 3-D printable self-adjustable glasses, communities not only gain access to far more diversity in product design, as the glasses can …

Crystallization Kinetics And Viscosity Of Cu47ti33zr11ni8x1 (X=Si, Sn) Metallic Glasses, Laichang Zhang, M Calin, M Adam, J Eckert

Faculty of Engineering - Papers (Archive)

Crystallization kinetics of Cu47Ti34Zr11Ni8 and Cu47Ti33Zr11Ni8X1 (X = Si, Sn) metallic glasses was investigated by the Johnson-Mehl-Avrami method. The Avrami exponent of 2.5

Investigation Of The Magnetic Properties In Strontium–Borate Vanadate Glasses, Manford Chinkhota, Petru S. Fodor, G. D. Khattak, Lowell E. Wenger

Physics Faculty Publications

To further elucidate the nature of the valence state of V ions in vanadate glasses,magnetic susceptibility measurements in the temperature range of 5 to 300 K have been performed on a series of vanadium–strontium–borate (V2O5+SrO+B2O3) oxide glasses with V2O5 concentrations greater than 50 mol %. The magnetic susceptibility for these oxide glasses is found to consist of a temperature-independentparamagnetic contribution arising from V2O5 and a Curie–Weiss temperature-dependent contribution associated with magnetic V4+ ions being present in concentrations between 2% and 10% of the total V concentration. The negative Curie–Weiss temperatures in the range of 0 to −2.8 K indicate a …

The Aperiodic Crystal Picture And Free Energy Barriers In Glasses, Randall W. Hall, Peter G. Wolynes

Collected Faculty and Staff Scholarship

The aperiodic crystal picture associates the glass transition with freezing into a nonperiodic structure. Dynamics in the glassy state involves activated jumps between different aperiodic free energy minima. Activation barriers may be estimated through the use of freezing theory and the theory of dense solids. The results resemble, but are distinct from, free volume theory. Reasonable fits to experimental data are obtained.