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fort Worth, TX, United States

Texas Christian University is a private, coeducational university located in Fort Worth, Texas. The campus is located on 272 acres about three miles from downtown Fort Worth. TCU is affiliated with, but not governed by, the Disciples of Christ. Its mascot is the "horned frog", and women's teams are known as the Lady Frogs. For most varsity sports TCU competes in the Big 12 conference of the NCAA's Division I. The university enrolls around 9,725 students, with 8,456 being undergraduates. As of October 2011, TCU's total endowment was $1.2 billion. Wikipedia.

Janesko B.G.,Texas Christian University
Physical Chemistry Chemical Physics | Year: 2014

This work presents a computational mechanistic study of the acid-catalyzed hydrolysis of lignin β-O-4 linkages in ionic liquid solvents. Model compound 2-hydroyxyethyl phenyl ether undergoes dehydration to vinyl phenyl ether followed by hydrolysis to phenol and "Hibbert's ketones". Larger model compound α-hydroxy-phenethyl phenyl ether illustrates an E1 dehydration mechanism involving resonance-stabilized carbocations. Continuum models for ionic liquid solvents indicate that solvation can significantly affect the reaction rates. The tested continuum ionic liquid solvents give similar results, and differ significantly from continuum organic solvents with comparable dielectric constants. The acidic ionic liquid cation 1-H-3-methylimidazolium has lower predicted catalytic activity than hydronium or HCl, consistent with the former's relatively small acid dissociation constant. Calculations with dispersion-corrected density functionals give similar behavior. Calculations on Lewis acidic metal chlorides used experimentally for lignin hydrolysis suggest that the metal chloride may participate in the initial dehydration. These results provide a baseline for future studies of improved hydrolysis catalysts. © 2014 the Owner Societies. Source

Montchamp J.-L.,Texas Christian University
Accounts of Chemical Research | Year: 2014

Organophosphorus compounds are important in everyday applications ranging from agriculture to medicine and are used in flame retardants and other materials. Although organophosphorus chemistry is known as a mature and specialized area, researchers would like to develop new methods for synthesizing organophosphorus compounds to improve the safety and sustainability of these chemical processes.The vast majority of compounds that contain a phosphorus-carbon bond are manufactured using phosphorus trichloride (PCl 3) as an intermediate. However, these reactions require chlorine, and researchers would like to avoid the use of PCl3 and develop safer chemistry that also decreases energy consumption and minimizes waste. Researchers have already proposed and discussed two primary strategies based on elemental phosphorus (P4 or Pred) or on phosphine (PH 3) as alternatives to PCl3. However, phosphinates, an important class of phosphorus compounds defined as any compound with a phosphorus atom attached to two oxygens, R1R2P(O)(OR) (R1/R2 = hydrogen/carbon), offer another option.This Account discusses the previously neglected potential of these phosphinates as replacements of PCl3 for the preparation of organophosphorus compounds. Because of their strong reductive properties, industry currently uses the simplest members of this class of compounds, hypophosphites, for one major application: electroless plating. In comparison with other proposed PCl 3 surrogates, hypophosphorous derivatives can offer improved stability, lower toxicity, higher solubility, and increased atom economy. When their reducing power is harnessed to form phosphorus-carbon or phosphorus-oxygen bonds, these compounds are also rich and versatile precursors to organophosphorus compounds. This Account examines the use of transition metal-catalyzed reactions such as cross-coupling and hydrophosphinylation for phosphorus-carbon bond formation. Because the most important industrial organophosphorus compounds include compounds triply or quadruply bound to oxygen, I also discuss controlled transfer hydrogenation for phosphorus-oxygen bond formation. I hope that this Account will further promote research in this novel and exciting yet much underdeveloped area of phosphinate activation. © 2013 American Chemical Society. Source

Hubbard T.L.,Texas Christian University
Psychological Bulletin | Year: 2014

If an observer sees a flashed (briefly presented) object that is aligned with a moving target, the perceived position of the flashed object usually lags the perceived position of the moving target. This has been referred to as the flash-lag effect, and the flash-lag effect has been suggested to reflect how an observer compensates for delays in perception that are due to neural processing times and is thus able to interact with dynamic stimuli in real time. Characteristics of the stimulus and of the observer that influence the flash-lag effect are reviewed, and the sensitivity or robustness of the flash-lag effect to numerous variables is discussed. Properties of the flash-lag effect and how the flash-lag effect might be related to several other perceptual and cognitive processes and phenomena are considered. Unresolved empirical issues are noted. Theories of the flash-lag effect are reviewed, and evidence inconsistent with each theory is noted. The flash-lag effect appears to involve low-level perceptual processes and high-level cognitive processes, reflects the operation of multiple mechanisms, occurs in numerous stimulus dimensions, and occurs within and across multiple modalities. It is suggested that the flash-lag effect derives from more basic mislocalizations of the moving target or flashed object and that understanding and analysis of the flash-lag effect should focus on these more basic mislocalizations rather than on the relationship between the moving target and the flashed object. © 2014 American Psychological Association. Source

Schoenherr T.,Michigan State University | Swink M.,Texas Christian University
Journal of Operations Management | Year: 2012

This paper revisits Frohlich and Westbrook's arcs of integration concept [Arcs of integration: an international study of supply chain strategies. Journal of Operations Management 2001, 19 (2) pp. 185-200]. Using survey responses from 403 supply chain professionals, we compare the arcs of integration group memberships generated with our sample to the original study, rationalize the classification scheme, and assess the impact of supply chain integration strategies on quality, delivery, flexibility and cost performance. In doing so we cross-validate Frohlich and Westbrook's framework with a more recent and broader sample of data utilizing multi-dimensional performance measures collected from supply chain managers. We ground these relationships in the relational and resource-based views of the firm. We also extend Frohlich and Westbrook's study by investigating the moderating role of internal integration on the relationships between arcs of integration and performance. In accordance with information processing theory, the results indicate that internal integration strengthens the positive impacts of external integration on both delivery and flexibility performance. However, the theory is not supported for either quality or cost performance. Overall, our study confirms and extends the work of Frohlich and Westbrook, augments theories used to describe supply chain integration efforts, and provides practical implications for managers. © 2011 Elsevier B.V. All rights reserved. Source

Semiconducting polymers with π-conjugated backbones show promise in fields such as photovoltaics. Practical applications of conjugated polymers require precise control over the polymer's electronic band structure. Several new classes of density functional approximation, including screened hybrids, semilocal Minnesota functionals, and Rung 3.5 functionals, show potential for improved predictions of conjugated polymer band structures. This work compares these methods to standard global hybrid density functionals for bandgaps and band structures of representative conjugated polymers. The new methods exhibit particular promise for modeling three-dimensionally periodic bulk polymers, which can be problematic for global hybrids. © 2011 American Institute of Physics. Source

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