This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The award supports the renovation of the research infrastructure of VanderWerf Hall on the campus of Hope College. VanderWerf Hall was constructed in 1964, housing the departments of Physics and Mathematics. VanderWerf Hall now houses four departments: Computer Science, Engineering, Mathematics, and Physics. Each of these four departments is active in original research (about 30 faculty members); each research program involves researchers working with undergraduate students (about 50 per year). The research areas to be enhanced by the award range from development of electrodeposition of magnetic thin films and layered structures to fundamental nuclear physics to mathematical biology, among many others. The building's research space has evolved over the last 45 years, cannibalizing classrooms and installing enough equipment to perform research, but lacking a cohesive focus to design and even space for some departmental research efforts. Updating and renovating the scientific research spaces in VanderWerf Hall will transform cramped, inadequate facilities into safer environments and will broaden participation in research by improving access by everyone to research facilities, allowing increased use of equipment, and allowing increased access to research by undergraduate students.
This project supported renovation of seven research spaces in the VanderWerf/VanZoeren science facilities at Hope College: Civil Engineering Laboratory (Dr. Jeffery Brown) Hope College Ion Beam Analysis Laboratory (Dr. Graham Peaslee and Dr. Paul DeYoung) Materials Characterization Laboratory (Dr. Graham Peaslee, Dr. Jennifer Hampton and Dr. Mary Anderson) Microwave Research Laboratory (Dr. Stephan Remillard) Nuclear Science Laboratory (Dr. Paul DeYoung and Dr. Graham Peaslee) Radiodating Laboratory (Dr. Graham Peaslee and Dr. Paul DeYoung) Surface Science Laboratory (Dr. Jennifer Hampton) In addition to the faculty researchers directly impacted through renovation of their laboratories, a significant number of chemistry, biology and geology faculty research programs have been impacted by the project due to their use of equipment in the Ion Beam analysis laboratory, Radiodating laboratory and Materials Testing laboratory. In addition, dozens of undergraduate researchers a year work directly in the research programs housed in these labs or use the multi-user facilities mentioned above. Some specific examples of research results that were made possible by this rennovation project include: Identification of the sources of sediment which has led to the current eutrophic state of Lake Macatawa. Suspended sediment samples were collected throughout the watershed after a significant rainfall has occurred using sediment traps. Scanning Electron Microscopy/Energy Dispersive Spectrometry (SEM/EDS) and Particle Induced X-Ray Emission (PIXE) results demonstrate that there is elemental variation between sites, as well as between sample collections; these results are reproducible and have been supported by analysis of sediment phosphate content. Color analysis using cathodolumnescence imaging has shown promise in differentiating subtle differences between areas of the watershed. Varying characteristics of sediment contribute to each site’s unique sediment color fingerprint. Using Principle Component Analysis of the red, blue and green colors from cathodolumnescence imaging of the sediment produced statistical variations in sediment colors that can serve as a finger print for sediment from several sub-watersheds within the Macatawa watershed. Measurements of sediment fingerprinting of radioisotopes such as 137Cs and 210Pb in the Lake Macatawa watershed have proven useful in identifying the source of sediments flowing into the watershed after major rain events. Nanoporous thin films are interesting candidates to catalyze certain reactions because of their large surface areas. This specific project focuses on the deposition of Ni and NiCu thin films on a gold substrate and further explores the catalysis of the hydrogen evolution reaction (HER). Depositions are created using controlled potential electrolysis, a process where the potential at which the metal alloy deposition occurs is set and the length of time or total charge of the deposition is adjusted. Samples are then dealloyed using either DC potential amperometry with an applied constant potential or cyclic voltammetry for linear sweeping. Before and after the dealloying, all the samples are characterized using multiple techniques. Electrochemical capacitance measurements allow comparisons of sample roughness. HER measurements characterize the reactivity of the sample with respect to the specific catalytic reaction. Other methods for characterizing the samples include scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The use of SEM allows images to be taken of the deposition to determine the change in the structure pre- and post- dealloy of the sample. EDS allows the elemental composition of the deposition to be determined before and after the dealloy stage. The nonlinear response of High Temperature Superconducting (HTS) microwave resonator samples of Tl2Ba2CaCu2O8 (TBCCO) and YBa2Cu3O77(YBCO) on LaAlO3 (LAO) substrates was analyzed around the transition temperature (Tc). Nonlinearity is an undesirable response in commercially-produced superconductors that can potentially be minimized through the understanding of its effects through our investigation. HTS microstrip lines were examined with a travelling microscope and a scanning electron microscope (SEM) to determine the dimensions, geometry, and edge structures of each sample, and Energy-dispersive X-ray Spectroscopy (EDS) was used to verify the material composition. Multi-tone measurements of even and odd order intermodulation distortion (IMD) currents were performed utilizing a simultaneous and synchronous measurement technique developed at Hope College. Around their respective Tcs, resonators of the two material systems exhibited different even and odd order IMD currents. The degree to which the superconducting current breaks time reversal symmetry (TRSB) is revealed by the ratio of the 2nd and 3rd order IMD levels. In YBCO samples, this ratio steadily decreased with increasing temperature, but then rapidly increased through Tc, indicating a considerable amount of TRSB. TBCCO showed a steady decrease in this ratio, as well, with increasing temperature, but did not show any indication of a rise in TRSB whilst approaching Tc. In TBCCO, 3rd order IMD exhibited a peak around Tc which is consistent with the nonlinear Meissner effect. TBCCO also appears to show nonlinearity past Tc much more than does YBCO, indicating the possibility of quantum mechanical fluctuations: a phenomenon associated with anisotropic superconductivity.
