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Full-Text Articles in Other Chemical Engineering

Use Of Calcium Hypochlorite As A Sanitizer For Seeds Used For Sprouting: Task #2; Impact: Improved Alfalfa Decontamination Technologies, Emily Damron, Carrie Klein, Melissa Leach, Jordan Mourot, Tom Murphy, Amy Seamans, Ryan Wilson Jan 2005

Use Of Calcium Hypochlorite As A Sanitizer For Seeds Used For Sprouting: Task #2; Impact: Improved Alfalfa Decontamination Technologies, Emily Damron, Carrie Klein, Melissa Leach, Jordan Mourot, Tom Murphy, Amy Seamans, Ryan Wilson

Inquiry: The University of Arkansas Undergraduate Research Journal

Consumption of raw or lightly cooked alfalfa sprouts has been a concern of the U.S. Food and Drug Administration (FDA) in recent years due to connections between sprouts and foodborne illnesses. Researchers have identified, contaminated seeds as the primary source of alfalfa sprouts contamination. Contamination of alfalfa seeds can originate in the field, harvesting, storing, or sprouting. Two pathogens of particular concern on alfalfa seeds are Escherichia coli 0157:H7 (E. coli) and Salmonella. These pathogens are capable of producing biofilms that provide protection for individual cells and allow for survival in otherwise hostile environments, including some disinfectant washes. Other factors …


Inorganic Supramolecular Host Architectures:  [(M@18c6)2][Tli4]·2h2o, M = 0.5 Tl, (Nh4,Nh3), (H3o,H2o), Franziska Rieger, Anja V. Mudring Jan 2005

Inorganic Supramolecular Host Architectures:  [(M@18c6)2][Tli4]·2h2o, M = 0.5 Tl, (Nh4,Nh3), (H3o,H2o), Franziska Rieger, Anja V. Mudring

Anja V. Mudring

The compounds [(M@18c6)2][TlI4]·2H2O, M = Tl, (NH4,NH3), (H3O,H2O) (cubic, Fd3̄; a = 1481.00 pm, for M = 0.5 Tl, a = 1304.65 pm for M = (NH4,NH3), a = 1313.67 pm for M = (H3O,H2O)) can be obtained from solution in the presence of traces of transition metal halides (like copper and mercury halides). Apparently the transition metal cations work as a template in the form of tetrahedral [MX4] units during the synthesis of the supramolecular host architecture. That the compounds are versatile host lattices for tetrahedrally coordinated transition metal units becomes obvious by the large group of known host−guest …


The Quadrupole Moment Of The 3/2+ Nuclear Ground State Of Au197 From Electric Field Gradient Relativistic Coupled Cluster And Density-Functional Theory Of Small Molecules And The Solid State, Peter Schwerdtfeger, Radovan Bast, Michael C.L. Gerry, Christoph R. Jacobs, Martin Jansen, Vladimir Kello, Anja V. Mudring, Andrzej J. Sadlej, Trond Saue, Tilo Sohnel, Friedrich E. Wagner Jan 2005

The Quadrupole Moment Of The 3/2+ Nuclear Ground State Of Au197 From Electric Field Gradient Relativistic Coupled Cluster And Density-Functional Theory Of Small Molecules And The Solid State, Peter Schwerdtfeger, Radovan Bast, Michael C.L. Gerry, Christoph R. Jacobs, Martin Jansen, Vladimir Kello, Anja V. Mudring, Andrzej J. Sadlej, Trond Saue, Tilo Sohnel, Friedrich E. Wagner

Anja V. Mudring

An attempt is made to improve the currently accepted muonic value for the Au197 nuclear quadrupole moment [+0.547(16)×10−28m2] for the 3/2+ nuclear ground state obtained by Powers et al. [Nucl. Phys.A230, 413 (1974)]. From both measured Mössbauer electric quadrupole splittings and solid-state density-functional calculations for a large number of gold compounds a nuclear quadrupole moment of +0.60×10−28m2 is obtained. Recent Fourier transform microwave measurements for gas-phase AuF, AuCl, AuBr, and AuI give accurate bond distances and nuclear quadrupole coupling constants for the Au197isotope. However, four-component relativistic density-functional calculations for these molecules yield unreliable results for the Au197 nuclear quadrupole moment. …


Rare-Earth Iodides In Ionic Liquids:  The Crystal Structure Of [Set3]3[Lni6] (Ln = Nd, Sm), Anja V. Mudring, Arash Babai Jan 2005

Rare-Earth Iodides In Ionic Liquids:  The Crystal Structure Of [Set3]3[Lni6] (Ln = Nd, Sm), Anja V. Mudring, Arash Babai

Anja V. Mudring

Crystals of [SEt3]3[LnI6] (Ln = Nd, Sm) were obtained by the reaction of LnI2 with the ionic liquid [SEt3][Tf2N] [Tf2N = bis(trifluoromethanesulfonyl)imide]. The compounds are characterized by octahedral [LnI6]3- units that are surrounded by a distorted cube of triethylsulfonium cations.


Anhydrous Praseodymium Salts In The Ionic Liquid [Bmpyr][Tf2n]:  Structural And Optical Properties Of [Bmpyr]4[Pri6][Tf2n] And [Bmyr]2[Pr(Tf2n)5], Arash Babai, Anja V. Mudring Jan 2005

Anhydrous Praseodymium Salts In The Ionic Liquid [Bmpyr][Tf2n]:  Structural And Optical Properties Of [Bmpyr]4[Pri6][Tf2n] And [Bmyr]2[Pr(Tf2n)5], Arash Babai, Anja V. Mudring

Anja V. Mudring

Purposely designed ionic liquids can be excellent solvents for spectroscopic studies of rare earth compounds. Absorption and emission spectra of anhydrous PrI3 and Pr(Tf2N)3 in the ionic liquid 1,1-n-butyl-methylpyrrolidinium bis(trifluoromethanesulfonyl)amide, [bmpyr][Tf2N], at room temperature are presented together with the emission spectra of solid [bmpyr]2[Pr(Tf2N)5] and [bmpyr]4[PrI6][Tf2N]. After excitation into the 3P1 level, remarkable luminescence not only from the 1D2 level but also from the 3P0 and even from the 3P1 level is observed. Amazingly in the case of the solid compounds and even more astonishing for a solution of Pr(Tf2N)3 in [bmpyr][Tf2N] the strongest luminescence transitions start from the 3P0 …


Lone Pair Effect In Thallium(I) Macrocyclic Compounds, Anja V. Mudring, Franziska Rieger Jan 2005

Lone Pair Effect In Thallium(I) Macrocyclic Compounds, Anja V. Mudring, Franziska Rieger

Anja V. Mudring

The role of the inert (lone) pair of electrons in thallium(I) salts is studied by comparison of the compounds [Tl@18-crown-6]+X- (X = TlI4, ClO4) and [K@18-crown-6]+ClO4-. In contrast to common introductory chemistry textbook opinions, the paradigm that s−p hybridization is a prerequisite for an inert electron pair to become stereochemically active in compounds of the heavier main group elements has to be revised. Instead, an inert pair of electrons is expected to become stereochemically involved whenever it is forced to participate in antibonding orbital interactions with its surroundings, and there is the possibility for a structural distortion that minimizes these …


The Grain Size And Microstructure Of Jet-Electroplated Damascene Copper Films, Stacy H. Gleixner, Andrew Tzanavaras, Gregory Young Jan 2005

The Grain Size And Microstructure Of Jet-Electroplated Damascene Copper Films, Stacy H. Gleixner, Andrew Tzanavaras, Gregory Young

Faculty Publications

Electroplated damascene copper is rapidly replacing aluminum-copper alloys for on-chip interconnect metallization in advanced ultralarge scale integrated (ULSI) semiconductor devices. In addition to a high degree of (111) crystallographic texture, large defect-free grains are desired to enhance the performance and reliability of copper interconnects in such devices. The brightening additive level and dc current density of electroplating baths are two parameters that affect the process gap-filling capability and the degree of additive incorporation in these copper films. Additive incorporation can inhibit grain growth during the room-temperature recrystallization process and therefore affect the final grain size in electroplated copper films. This …


Data Management And Visualization Of X-Ray Diffraction Spectra From Thin Film Ternary Composition Spreads, I. Takeuchi, C. J. Long, O. O. Famodu, M. Murakami, Jason R. Hattrick-Simpers, G. W. Rubloff, M. Stukowski, K. Rajan Jan 2005

Data Management And Visualization Of X-Ray Diffraction Spectra From Thin Film Ternary Composition Spreads, I. Takeuchi, C. J. Long, O. O. Famodu, M. Murakami, Jason R. Hattrick-Simpers, G. W. Rubloff, M. Stukowski, K. Rajan

Faculty Publications

We discuss techniques for managing and visualizing x-ray diffraction spectrum data for thin film composition spreads which map large fractions of ternary compositional phase diagrams. An in-house x-ray microdiffractometer is used to obtain spectra from over 500 different compositions on an individual spread. The MATLAB software is used to quickly organize the data and create various plots from which one can quickly grasp different information regarding structural and phase changes across the composition spreads. Such exercises are valuable in rapidly assessing the “overall” picture of the structural evolution across phase diagrams before focusing in on specific composition regions for detailed …


Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason R. Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. L. Wang, J. P. Liu, S. E. Lofland, Somdev Tyagi, J. W. Freeland, D. Giubertoni, M. Bersani, M. Anderle Jan 2005

Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason R. Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. L. Wang, J. P. Liu, S. E. Lofland, Somdev Tyagi, J. W. Freeland, D. Giubertoni, M. Bersani, M. Anderle

Faculty Publications

We have fabricated Fe∕Sm–Co bilayers with gradient Fe thicknesses in order to systematically study the dependence of exchange coupling on the thickness of the Fe layer. The Fe layer was deposited at two different temperatures (150 and 300°C) to study the effect of deposition temperature on the exchange coupling. Magneto-optical Kerr effect and x-ray magnetic circular dichroism (XMCD) have been employed as nondestructive rapid characterization tools to map the magnetic properties of the gradient samples. Systematic enhancement in exchange coupling between the soft layer and the hard layer is observed as the soft layer thickness is decreased. Separate exchange couplings …


The Grain Size And Microstructure Of Jet-Electroplated Damascene Copper Films, Stacy H. Gleixner, Andrew Tzanavaras, Gregory Young Jan 2005

The Grain Size And Microstructure Of Jet-Electroplated Damascene Copper Films, Stacy H. Gleixner, Andrew Tzanavaras, Gregory Young

Stacy H. Gleixner

Electroplated damascene copper is rapidly replacing aluminum-copper alloys for on-chip interconnect metallization in advanced ultralarge scale integrated (ULSI) semiconductor devices. In addition to a high degree of (111) crystallographic texture, large defect-free grains are desired to enhance the performance and reliability of copper interconnects in such devices. The brightening additive level and dc current density of electroplating baths are two parameters that affect the process gap-filling capability and the degree of additive incorporation in these copper films. Additive incorporation can inhibit grain growth during the room-temperature recrystallization process and therefore affect the final grain size in electroplated copper films. This …


Study On Improving The Opacity Of Paper Using Adjunct Filler Pigments, Pankaj Chowdhury, Puskar Gupta, Manoj Kumar, Pramod Bajpai, Raghavan Varadhan Dec 2004

Study On Improving The Opacity Of Paper Using Adjunct Filler Pigments, Pankaj Chowdhury, Puskar Gupta, Manoj Kumar, Pramod Bajpai, Raghavan Varadhan

PC

No abstract provided.