Logan J.L.,Washington & Jefferson College |
Rumbaugh C.E.,Washington & Jefferson College
Journal of Chemical Education | Year: 2012
"The Chemistry of Perfume" is a lab-only course for nonscience majors. Students learn fundamental concepts of chemistry through the context of fragrance, a pervasive aspect of daily life. The course consists of laboratories pertaining to five units: introduction, extraction, synthesis, characterization, and application. The introduction unit acquaints students with basic perfume terminology and the idea that chemical structure relates to scent. The extraction unit focuses on capturing and isolating fragrant essences from natural materials, whereas the synthetic unit considers mimicking such scents through chemical reactions. In the characterization unit, students analyze the components of perfume and fragrant materials. The course ends with the application unit in which students incorporate their fragrances into consumer products and toiletries. Curriculum structure, content, and student feedback are described. This perfume lab course results from an effort to increase interest in chemistry among nonscience students and encourage interdisciplinary learning. © 2012 American Chemical Society and Division of Chemical Education, Inc.
Dey B.,Carnegie Mellon University |
McCracken M.E.,Carnegie Mellon University |
McCracken M.E.,Washington & Jefferson College |
Ireland D.G.,University of Glasgow |
Meyer C.A.,Carnegie Mellon University
Physical Review C - Nuclear Physics | Year: 2011
The complete expression for the intensity in pseudo-scalar meson photoproduction with a polarized beam, target, and recoil baryon is derived using a density matrix approach that offers great economy of notation. A Cartesian basis with spins for all particles quantized along a single direction, the longitudinal beam direction, is used for consistency and clarity in interpretation. A single spin-quantization axis for all particles enables the amplitudes to be written in a manifestly covariant fashion with simple relations to those of the well-known Chew-Goldberger-Low-Nambu formalism. Possible sign discrepancies between theoretical amplitude-level expressions and experimentally measurable intensity profiles are dealt with carefully. Our motivation is to provide a coherent framework for coupled-channel partial-wave analysis of several meson photoproduction reactions, incorporating recently published and forthcoming polarization data from Jefferson Lab. © 2011 American Physical Society.
Hoop C.L.,Washington & Jefferson College |
Iuliucci R.J.,Washington & Jefferson College
Solid State Nuclear Magnetic Resonance | Year: 2013
The 13C chemical-shift anisotropy in anthracene derivatives (9,10-dimethylanthracene, 9,10-dihydroanthracene, dianthracene, and triptycene) has been measured by the 2D FIREMAT timed pulse sequence and the corresponding set of principal values has been determined by the TIGER processing method. These molecules expand the data base of 13C CSA measurements of fused aromatic rings some bridged by sp3 carbon resulting in an unusual bonding configuration, which leads to distinctive aromatic 13C CSA values. Crystal lattice distortions to the CSA were observed to change the isotropic shift by 2.5 to 3.3 ppm and changes as large as 8.3 ppm in principal components. Modeling of the CSA data by GIPAW DFT (GGA-PBE/ultrafine) shielding calculations resulted in an rms chemical-shift distance of 2.8 ppm after lattice including geometry optimization of the diffraction structures by the GIPAW method at GGA-PBE/ultrafine level. Attention is given to the substituted aromatic carbon in the phenyl groups (here forth referred to as the α-carbon) with respect to CSA modeling with electronic methods. The 13C CSA of this position is accurately determined due to its spectral isolation of the isotropic shift that limits overlap in the FIREMAT spectrum. In cases where the bridging ring is sp3 carbon, the current density is reduced from extending beyond the peripheral phenyl groups; this plays a significant role in the magnetic shielding of the α-position. Nuclear independent chemical-shift calculations based on GIAO DFT (B3LYP/6-31G(d)) shielding calculations were used to model the intramolecular π-interactions in dianthracene and triptycene. These NICS results estimate the isotropic shift of the α-position in dianthracene to be insignificantly affected by the presence of the neighboring aromatic rings. However, a notable change in isotropic shielding, Δσiso=-2.1 ppm, is predicted for the α- position of triptycene. Experimentally, the δ22 principal component at the α-position for both dianthracene and triptycene increases by at least 12 ppm compared to 9,10-dihydroanthracene. To rationalize this change, shielding calculations in idealized structures are explored. The spatial position of the bicyclic scaffolding of the bridging ring plays a key role in the large increase in δ22 for the α-carbon. © 2013 Elsevier Inc. All rights reserved.
Lombardi T.,Washington & Jefferson College
Leonardo | Year: 2014
This paper analyzes the co-occurrence network of saints in the corpus of images of St. Francis from 1230 to 1320 AD. The network of saints grows by preferential attachment reflecting the intercessory function of the artwork. The network, therefore, highlights important connections between intellectual and physical culture. © 2014 ISAST.
Piko B.E.,Washington & Jefferson College |
Keegan A.L.,Washington & Jefferson College |
Leonard M.S.,Washington & Jefferson College
Tetrahedron Letters | Year: 2011
A concise synthesis of the isoindolobenzazepine aporhoeadane core is achieved in four steps from homoveratrylamine and ninhydrin. © 2011 Elsevier Ltd. All rights reserved.
Quinones R.,Marshall University |
Rodriguez K.,Washington & Jefferson College |
Iuliucci R.J.,Washington & Jefferson College
Thin Solid Films | Year: 2014
Zinc oxide (ZnO) nanoparticles have emerged as a fascinating metal oxide semiconductor nanomaterial due largely to their wide array of properties that can be altered by surface modification. For example electrical and photonic properties include a range of conductivity from metallic to insulating (n-type and p- type conductivity), wide-band gap semiconductivity, room-temperature ferromagnetism, and chemical-sensing. Recently there has been much interest in the electronic and photonic properties of ZnO nanostructures as foreseeable applications include solar cells and laser diodes. For such purposes, controlling the surface functionalization is important and can be tailored by the chemical attachment of organic acids to the surface. The oxide surface readily reacts with organics forming self-assembled alkylphosphonate films. In this study, ZnO nanoparticles were modified using self-assembly thin films with phosphonic functional head groups. The amount of organic acid used in preparation of the thin film was shown to be important to the nanoparticle surface coverage. The modified ZnO nanoparticles were then characterized using infrared spectroscopy, powder X-ray diffraction, solid-state nuclear magnetic resonance, and scanning electron microscopy-energy dispersive X-ray spectroscopy. The interfacial bonding was identified by spectroscopy analysis to be the bidentate and tridentate motifs between the phosphonic head group and the oxide surface. Work function modification was measured using Ultraviolet photoelectron spectroscopy. The influences of temperature, humidity, and solvent rinse on the stability of the surface modifications were performed. © 2014 Elsevier B.V. All rights reserved.
Davitt K.,Ecole Normale Superieure de Paris |
Pettersen M.S.,Washington & Jefferson College |
Rolley E.,Ecole Normale Superieure de Paris
Langmuir | Year: 2013
From simple models of thermally activated contact line dynamics far below the depinning transition, one expects the velocity to depend exponentially on the applied force and the activation area to be the size of the defects on the surface. We study contact line motion on evaporated gold films and find that the dynamics are activated, but the activation area is not straightforwardly linked to the surface roughness. Surprisingly, the activation area can be significantly smaller than any features on the surface. Furthermore, it depends strongly on the liquid. We show that this indicates that the line is close to the depinning threshold at experimentally accessible velocities. A model based on independent defects is developed and used to show deviations from the purely exponential law. The dynamics are written entirely in terms of properties of the surface and partially wetting liquid. In addition, we are able to show that the region of validity of models of thermal activation on mesoscopically rough surfaces typically corresponds to velocities of less than 1 mm/s. © 2013 American Chemical Society.
Sunderland D.P.,Washington & Jefferson College
Journal of Chemical Education | Year: 2014
A solid-state crystal structure laboratory exercise for undergraduates in either a general chemistry course or a more advanced inorganic chemistry course is described. Students explore the lattice arrangement of atoms in unit cells by building models supplied by the Institute for Chemical Education. Emphasis is placed on building three-dimensional visual models of various crystal systems to display close packing of atoms, to identify tetrahedral and octahedral holes, to reveal number of atoms per unit cell, and to highlight ion coordination numbers and size differences. The relationship between solid-state bonding and a material's physical properties is emphasized for elemental carbon. © 2014 The American Chemical Society and Division of Chemical Education, Inc.
Glagola C.P.,Washington & Jefferson College |
Miceli L.M.,Washington & Jefferson College |
Milchak M.A.,Washington & Jefferson College |
Halle E.H.,Washington & Jefferson College |
Logan J.L.,Washington & Jefferson College
Langmuir | Year: 2012
Polystyrene-block-poly(ethylene oxide) (PS-PEO) is an amphiphilic diblock copolymer that undergoes microphase separation when spread at the air/water interface, forming nanosized domains. In this study, we investigate the impact of PS by examining a series of PS-PEO samples containing constant PEO (∼17-000 g•mol -1) and variable PS (from 3600 to 200-000 g•mol -1) through isothermal characterization and atomic force microscopy (AFM). The polymers separated into two categories: predominantly hydrophobic and predominantly hydrophilic with a weight percent of PEO of ∼20% providing the boundary between the two. AFM results indicated that predominantly hydrophilic PS-PEO forms dots while more hydrophobic samples yield a mixture of dots and spaghetti with continent-like structures appearing at ∼7% PEO or less. These structures reflect a blend of polymer spreading, entanglement, and vitrification as the solvent evaporates. Changing the spreading concentration provides insight into this process with higher concentrations representing earlier kinetic stages and lower concentrations demonstrating later ones. Comparison of isothermal results and AFM analysis shows how polymer behavior at the air/water interface correlates with the observed nanostructures. Understanding the impact of polymer composition and spreading concentration is significant in leading to greater control over the nanostructures obtained through PS-PEO self-assembly and their eventual application as polymer templates. © 2012 American Chemical Society.
Agency: NSF | Branch: Standard Grant | Program: | Phase: MAJOR RESEARCH INSTRUMENTATION | Award Amount: 72.53K | Year: 2012
Proposal #: 12-29108
PI(s): Holland-Minkley, Amanda
Institution: Washington and Jefferson College
Title: MRI/Acq.: Acquisition of Eye Tracking System
This project from an undergraduate-serving institution, acquiring an Eye Tracking system, aims to add quantitative measures of changes in problem-solving techniques to more traditional outcomes-based assessments of student learning. The eye tracking system enables pursuing further work and greater quantitative analysis in design and usability research focused on issues such as the effect of the interface design of security-focused software on the secure behaviors and awareness of security features of the software users.
Current work at the institution focuses on the particular application of these methods in an introductory programming course. The Information Technology Leadership (ITL) faculty have broaden their research to encompass more mobile computing that has contributed in developing a collaboration with Biology faculty. In turn, this collaboration has given rise to a mobile application used when collecting ecological data in the field. A beta version, now under assessment, has been created and deployed where the eye tracking methods will be used to confirm that mobile technologies enable not only more accurate data collection, but better learning and retention on the part of the student researchers in the field.
This solely undergraduate institution core mission focuses on research involving significant undergraduate collaboration. In particular, the ITL Department is committed to enabling its majors to take part in significant research projects that allow them to act as true collaborators and not simply as coders or lab technicians. Thus, with an existing history of engaging undergraduates in design and usability research, a modern eye tracking system will strengthen the program making it accessible to more students. The system will play a role in classroom activities, labs, and independent projects. Students should gain fluency with the tool and with appropriate methods for using it in regular coursework. A service management course will be required for all seniors to partner with local non-profits to provide technical consulting or development. The system provides a platform for continued interdisciplinary research, including ongoing work in Biology and potential projects that involve Political Science, Gender and Women?s Studies, Sociology, and Psychology.