Chemical Research with Undergraduate Collaborators: Building Cyclic Polymers

Undergraduate research in chemistry provides not only a meaningful experience for the students, but is essential in getting research done. This talk will focus on an ongoing project in my lab: designing large molecules of specific shapes by studying the fundamental reactions. While results will be discussed, the talk will be tailored towards a general audience. I will attempt to highlight the outstanding contributions made by Bucknell students that have worked in my lab.

Using the Franck-Hertz Experiment To Illustrate Quantization Energy States of the Neon Atom by Electron Impact

na provide students with motivation for the study of quantum mechanics. That microscopic matter exists in quantized states can be demonstrated with modem versions of historic experiments: atomic line spectra (I), resonance potentials, and blackbody radiation. The resonance potentials of mercury were discovered by Franck and Hertz in 1914 (2). Their experiment consisted of bombarding atoms by electrons, and detecting the kinetic energy loss of the scattered electrons (3). Prior to the Franck-Hertz experiment, spectroscopic work bv Balmer and Rvdbere revealed that atoms emitted radiatibn at discrete ekergiis. The Franck-Hertz experiment showed directly that auantized enerm levels in an atom are real, not jist optiEal artifacts. atom can be raised to excited states by inelastic collisions with electrons as well as lowered from excited states by emission of photons. The classic Franck-Hertz experiment is carried out with mercury (4-7). Here we present an experiment for the study of resonance potentials using neon.

Experiment in Quantization: Atomic Line Spectra

Laboratory exercises that confront students with decisive ouantum ohenomena nrovide valuable motivation for the kudy of quantum m&hanics. The idea that microscopic matter exists in quantized states can be demonstrated with modern versions of historic experiments: atomic line snectra. blackbodv radiation. and resonance potentials. In this experiment, we present a strikingly simple and visual method for determining the wavelength of spectral lines. This experiment not only shows the inadequacy of classical physics, but also indicates the power of optical measurements.

Doubly-charged ethane ions: Solution to the dilemma of stability predicted by theory and instability observed in experiment

Potential energy curves have been computed for [C2H6]2+ ions and the results used to interpret the conspicuous absence of these ions in 2E mass spectra and in charge-stripping experiments. The energies and structures of geometry-optimized ground-state singlet and excited-state triplet [C2H6]2+ ions have been determined along with energies for different decomposition barriers and dissociation asymptotes. Although singlet and triplet [C2H6]2+ ions can exist as stable entities, they possess low energy barriers to decomposition. Vertical Franck-Condon transitions, involving electron impact ionization of ethane as well as charge-stripping collisions of [C2H6]+ ions, produce [C2H6]2+ ions which promptly dissociate since they are formed with energies in excess of various decomposition barriers. Appearance energies computed for doubly-charged ethane fragment ions are in accordance with experimental values.

Comparison of Model Chemistry and Density Functional Theory Thermochemical Predictions with Experiment for Formation of Ionic Clusters of the Ammonium Cation Complexed with Water and Ammonia; Atmospheric Implications

The G2, G3, CBS-QB3, and CBS-APNO model chemistry methods and the B3LYP, B3P86, mPW1PW, and PBE1PBE density functional theory (DFT) methods have been used to calculate ΔH° and ΔG° values for ionic clusters of the ammonium ion complexed with water and ammonia. Results for the clusters NH4+(NH3)n and NH4+(H2O)n, where n = 1−4, are reported in this paper and compared against experimental values. Agreement with the experimental values for ΔH° and ΔG° for formation of NH4+(NH3)n clusters is excellent. Comparison between experiment and theory for formation of the NH4+(H2O)n clusters is quite good considering the uncertainty in the experimental values. The four DFT methods yield excellent agreement with experiment and the model chemistry methods when the aug-cc-pVTZ basis set is used for energetic calculations and the 6-31G* basis set is used for geometries and frequencies. On the basis of these results, we predict that all ions in the lower troposphere will be saturated with at least one complete first hydration shell of water molecules.

Comparison of CBS-QB3, CBS-APNO, G2, and G3 thermochemical predictions with experiment for formation of ionic clusters of hydronium and hydroxide ions complexed with water

The GAUSSIAN 2, GAUSSIAN 3, complete basis set-QB3, and complete basis set-APNO methods have been used to calculate ΔH∘ and ΔG∘ values for ionic clusters of hydronium and hydroxide ions complexed with water. Results for the clusters H3O+(H2O)n andOH−(H2O)n, where n=1–4 are reported in this paper, and compared against experimental values contained in the National Institutes of Standards and Technology (NIST) database. Agreement with experiment is excellent for the three ab initio methods for formation of these clusters. The high accuracy of these methods makes them reliable for calculating energetics for the formation of ionic clusters containing water. In addition this allows them to serve as a valuable check on the accuracy of experimental data reported in the NIST database, and makes them useful tools for addressing unresolved issues in atmospheric chemistry.

A project-oriented course in probability and statistics for undergraduate electrical engineering students

An introductory course in probability and statistics for third-year and fourth-year electrical engineering students is described. The course is centered around several computer-based projects that are designed to achieve two objectives. First, the projects illustrate the course topics and provide hands-on experience for the students. The second and equally important objective of the projects is to convey the relevance and usefulness of probability and statistics to practical problems that undergraduate students can appreciate. The benefit of this course as to motivate electrical engineering students to excel in the study of probability concepts, instead of viewing the subject as one more course requirement toward graduation. The authors co-teach the course, and MATLAB is used for mast of the computer-based projects

A Laboratory Experiment Using Nanoindentation to Demonstrate the Indentation Size Effect

A laboratory experiment using nanoindentation to demonstrate the indentation size effect is described. This laboratory introduces students to sophisticated instrumentation at low cost and low risk and utilizes recent research in the materials community as its foundation. The motivation, learning objectives, experimental details, data, and data analysis are presented. This experiment is intended for use in an upper-division materials science elective at the university level and has been successfully used in laboratory courses for senior undergraduates and first-year graduate students at Stanford University and Santa Clara University.

The Design of XML-Based Model and Experiment Description Languages for Network Simulation

The Simulation Automation Framework for Experiments (SAFE) is a project created to raise the level of abstraction in network simulation tools and thereby address issues that undermine credibility. SAFE incorporates best practices in network simulationto automate the experimental process and to guide users in the development of sound scientific studies using the popular ns-3 network simulator. My contributions to the SAFE project: the design of two XML-based languages called NEDL (ns-3 Experiment Description Language) and NSTL (ns-3 Script Templating Language), which facilitate the description of experiments and network simulationmodels, respectively. The languages provide a foundation for the construction of better interfaces between the user and the ns-3 simulator. They also provide input to a mechanism which automates the execution of network simulation experiments. Additionally,this thesis demonstrates that one can develop tools to generate ns-3 scripts in Python or C++ automatically from NSTL model descriptions.

THE RELATIONSHIP BETWEEN PARENTING STYLES, LEARNING AUTONOMY, AND SCHOLASTIC ACHIEVEMENT IN UNDERGRADUATE COLLEGE STUDENTS

Throughout the years, the role that parents play with regard to a child’s academic achievement has been the source of considerable research. The type of parenting style employed by parents, whether it is authoritarian, authoritative, or permissive, has and continues to be a major theme in these studies. One area of particular interest that has been overlooked in these studies, however, is the influence that parents may have on a student’s learning autonomy. Learning autonomy is the idea that a student has internal motivation to learn or achieve. The purpose of this study was to investigate therelationship among the three styles of parenting, learning autonomy, perceived parental autonomy support, and scholastic achievement in undergraduate college students. Sixty-one participants were recruited at a small liberal arts college in the northeastern United States to complete questionnaires, which measured perceived parental authority of the participants’ parents, perceived parental autonomy support, and students’ own learning autonomy. The participants were also asked to list their grade point average. The results revealed positive and negative correlations between many of the variables in the study;however, simple regression analyses did not yield any statistically significant relationships between parental authority, learning autonomy, perceived autonomy support, and scholastic achievement.

Public Speaking Anxiety, Test Anxiety, and Academic Achievement in Undergraduate Students

Public speaking anxiety and test anxiety are both psychological difficulties which may adversely influence academic achievement in undergraduate students. Previous research has indicated that both public speaking anxiety and test anxiety are negatively correlated with academic performance, usually measured by grade point average. The purpose of this study was to assess the prevalence of public speaking anxiety, test anxiety, and their effects on academic achievement in a sample of undergraduate students, and to determine if certain groups of students are more likely to be affected than others. Although test anxiety and public speaking anxiety were both found to be negatively correlated with grade point average, these correlations were not statistically significant. Potential reasons for the lack of statistical congruence with previous studies, as well as implications for future research and treatment, are discussed.

The Impact of Gender and Pedagogy on the Development of Self-Regulated Learning Strategies in Undergraduate Engineering Classrooms

The purpose of this paper is to examine ways in which pedagogy and gender of instructor impact the development of self-regulated learning strategies as assessed by the Motivated Strategies for Learning Questionnaire (MSLQ) in male and female undergraduate engineering students. Pedagogy was operationalized as two general formats: lecture plus active learning techniques or problem-base/project-based learning. One hundred seventy-six students from four universities participated in the study. Within-group analyses found significant differences with regard to pedagogy, instructors’ gender, and student gender on the learning strategies and motivation subscales as operationalized by the MSLQ. Male and females students reported significant post-test differences with regard to the gender of instructor and the style of pedagogy. The results of this study showed a pattern where more positive responses for students of both genders were found with the same-gendered instructor. The results also suggested that male students responded more positively to project and problem-based courses with changes evidenced in motivation strategies and resource management. Female students showed decreases in resource management in these two types of courses. Further, female students reported increases in the lecture with active learning courses.

A Departmental Focus on High Impact Undergraduate Research Experiences

Undergraduate research experiences have become an integral part of the Hamilton College chemistry experience. The major premise of the chemistry department’s curriculum is that research is a powerful teaching tool. Curricular offerings have been developed and implemented to better prepare students for the independence required for successful undergraduate research experiences offered during the academic year and the summer. Administrative support has played a critical role in our ability to initiate and sustain scholarly research programs for all faculty members in the department. The research-rich curriculum is built directly upon or derived from the scholarly research agendas of our faculty members. The combined strengths and synergies of our curriculum and summer research program have allowed us to pursue several programmatic initiatives.