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In Mohawk Watershed Symposium, Abstracts and program

Abstract

The 15th Mohawk Watershed Symposium offers an exciting and diverse set of presentations on water quality, fisheries and habitats, flooding and resilience, and recreation and stewardship. The 2021-2026 Mohawk River Basin Action Agenda, our critical guiding document, focuses on conserving, preserving, and restoring the Mohawk River Watershed while helping to manage the ecosystem services for a sustainable future. Much of the defining discussion by stakeholders occurs at the annual Mohawk Watershed Symposium, and given this watershed blueprint, ongoing environmental change, and political headwinds, we see that the challenge ahead is enormous. Educational institutions and federal agencies - and many of our key stakeholders - are under threat. We need to ensure that science, engineering, and sound policy decisions guide our path forward. Now more than ever we need to redouble our efforts to advocate for clean water, fight the spread of invasive species, implement resilient flood mitigation projects, and understand how climate change has affected and will continue to affect almost everything in the watershed. The support of the DEC in this effort, and the partnership between the DEC and the Symposium, has made an enormous difference in fostering a sense of community and providing direction for watershed investigations. Additional support from Riverkeeper and the Mohawk-Hudson Land Conservancy is greatly appreciated, along with your attendance at this year’s Mohawk Watershed Symposium.

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Copyright Information: © 2025 Geosciences Department, Union College, Schenectady NY. All rights reserved. No part of the document can be copied and\/or redistributed, electronically or otherwise, without written permission from the Geosciences Department, Union College, Schenectady, NY, 12308, U.S.A.

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Geology Department, Union College

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In Alumni Files

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DigitalDocument

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In Alumni Files

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DigitalDocument

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In ARL Publications

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The Adirondack Chronology is intended to be a useful resource for researchers and others interested in the Adirondacks and Adirondack history.

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In The Idol Literary Magazine

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As the year comes to a close The Idol is back at it with our annual publication. Having come back strong last year, we came back this year more prepared than ever. We are beyond ecstatic to present some of the wonderful submissions we received this year. Thank you to everyone who submitted their work, the selection process is always difficult. We’ve truly enjoyed going through each and every piece we received. We would also like to thank our fabulous staff, and all the work they have done in helping with the selection process, layout, and endless patience throughout the year. We look forward to the coming years as we continue to grow!

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Book

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In Union College Permanent Collection

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COLLECTION<br />Scientific Instruments Collection<br /><br />Glass tube one end terminating with two bulbs of decreasing size. (see physical file for sketch)<br /><br />glass

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VisualArtwork

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In Steinmetz Symposium

Abstract

Planetary science is the study of different physical, atmospheric, and geological properties of planetary bodies in our Solar System. We are specifically interested in studying Jupiter's moon Europa, because of its large quantity of ice and water. This surplus of H2O is an essential piece in the search for life beyond Earth, which means in order to understand how life could exist outside of Earth, we must first enhance our intuition about the conditions on this icy moon. In this project, we use computational analysis methods and a program called SeaFreeze to model and calculate the thermodynamic properties of water and ice to learn more about how different pressure and temperature conditions influence their molecular behavior and phase changes. Through this analysis, we find relationships for the thermodynamic properties across phase boundaries and for each type of ice. We apply this analysis to create a model for the interior of the ice layer on Europa, plotting properties such as density, p-wave velocity, and s-wave velocity as functions of depth. We find a semi-linear relationship for these properties, and require future analyses to study the effects of salt in order to gain a full picture of the interior of Europa.

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In Steinmetz Symposium

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We explore the properties of the hydrosphere on Europa involving both a modeling technique and experimental methods. We perform a computational analysis of the thermodynamic properties for an ideal, pure-water Europan ice shell using a Python programming framework called SeaFreeze. We create four models assuming surface temperatures of either 50 K or 140 K and ice shell thicknesses of either 3 km or 30 km. We observe mostly linear trends for the density and seismic wave velocities with respect to depth, and find that surface temperatures have the greatest effect on the models. Simultaneously, we experimentally investigate the phase diagram of different saltwater concentrations in an attempt to further constrain the ice shell properties. We determine the freezing-melting points of 5%, 10%, and 20% by-weight NaCl-water solutions under constant pressures from 0 MPa to 70 MPa. We find that increasing the salt concentration, the pressure, or both decreases the freezing point temperature with a freezing point temperature depression of about -20 ¬?C from that of pure water at zero pressure. Based on our experimental results, we expect that adding NaCl to the pure-water computational models would cause them to have lower temperatures at the ice-water boundary, assuming saltwater has similar density and seismic wave velocity trends as pure-water. Areas of future development include continuing to explore the phase diagrams of different saltwater concentrations, including MgSO4, KCl, and varying combinations of all three salts, extending the pure-water SeaFreeze models to analyze Europa's subsurface ocean layer, implementing various new techniques to make our experiments more precise, and finally applying our results to the other icy moons, such as Ganymede or Callisto.

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In Honors Theses

Abstract

Multiplekm³ explosive deposits are exposed east of the South Sister volcanic range in central Oregon, centered around Bend. A comprehensive chemical and petrologic study of the crystal-poor (vol%) andesites (57-63 wt% SiO?) to rhyolites (>70 wt% SiO?) of the 5-6 named tuffs has not been completed. The physically distinct units of this study range in bulk chemistry: the Tumalo Tuff is 70-74.1 wt% SiO?, the overlying Shevlin Park Tuff is 63.8-65.1 wt% SiO?, and the Bend Pumice is 72.5-74 wt% SiO?. The Tumalo Tuff and Bend Pumice share similar rare earth element trends with a deep europium anomaly, while the Shevlin Park Tuff’s is much shallower. Comparison of trace element trends and FeO*/MgO ratios also suggest that the Tumalo Tuff and Bend Pumice are distinct from other units in the Central Cascade Arc. SEM quantitative analyses of ilmenites and magnetites were used in conjunction with the thermometer of Ghiorso and Evans (2008) to calculate the temperature and oxygen fugacity of the samples. The Shevlin Park Tuff (TT-12 and TT-13) give average temperatures of 959 ±33°C and 934 ±33°C, and fO? of 0.25 ±0.10 and 0.27 ±0.13 ?NNO, respectively. Tumalo Tuff and Bend Pumice samples show multiple compositional populations that give various temperatures and fO?. One particular subset in most of the Tumalo and Bend samples yields temperatures ~700°C and fO? of ?-0.22 ±0.62 ?NNO. These Fe-Ti oxides are in equilibrium with each other. The nearby 2-2.3 ka rhyolitic domes of the South Sister volcanic field record Fe-Ti oxide temperatures ~850?C and fO? ~0.7 ?NNO (Stelten and Cooper, 2012). The stark differences between the Tumalo Tuff and Bend Pumice when compared to South Sister rhyolites suggest that the magmas don’t share the same source despite geographic proximity. Unlike the South Sister complex and ii the Shevlin Park Tuff, which have discrete mineral compositions and display the chemistry and fugacity typical of a classic subduction zone, the Tumalo Tuff and Bend Pumice contain oxides that span a broad compositional range. The different oxide subsets which yield lower temperatures and fugacities indicate reducing conditions, which suggests an extensional environment. However, the populations with higher temperatures and fugacities give an arc-like signature. It is possible that multiple mechanisms including toroidal flow and reheating events during a period of transition from extension to subduction-driven magmatism are responsible for these younger explosive deposits in the Central Cascade Arc. A better understanding of this transition phase may give insight into the possibility of future hazards associated with the Tumalo Volcanic Center.

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Thesis

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In Honors Theses

Abstract

Morne Micotrin is a lava dome located at the head of the Roseau Valley in Dominica, Lesser Antilles, and has an explosive past; the valley was filled with ~3 km³ of pyroclastic deposits from 65-25 ka. The andesitic dome (59-62 wt% SiO₂) contains two distinct types of enclaves, coarse-grained and fine-grained, which differ texturally and compositionally from the host and each other. Enclaves provide evidence of magma mingling and mixing processes at depth, which may be introducing heat and volatiles into the magma chamber and triggering eruptions. Fine-grained enclaves (52-54 wt% SiO₂) are 1-15 cm in diameter and saturated in plagioclase, opx, cpx, and two oxides. Fine-grained enclaves are vesicular and lack microlites and matrix glass. Coarse-grained enclaves (55-56 wt% SiO₂) are larger, 3-20 cm, lack cpx phenocrysts, and contain plagioclase microlites. Coarse-grained enclaves are vesicular as well, a characteristic not observed in the host, and the margins are diffuse compared to the sharp fine-grained enclave margins. Coarse-grained enclave oxides are highly exsolved, and two oxides yielded temperatures of 890± 91°C and 774± 168°C, whereas fine-grained enclave oxides yielded temperatures of 891± 74°C and 794± 60°C. Both enclave types yielded higher fO₂ values than the host (average host yield fO₂ values of 0.30± 0.15, coarse-grained enclaves yield fO₂ values of 1.00± 0.23 and 1.49± 1.22, fine-grained enclaves yield fO₂ values of 0.42± 0.23 and 0.60± 0.21, all relative to DNNO). Mineral zoning in the enclaves is more complex than in the host. Plagioclase is normally and reversely zoned in all samples and ranges from An₄₀ to An₉₀in the host and enclaves. Many enclave plagioclase exhibit potassic rims, up to Or₂₀. Opx in all samples display mostly reverse zoning (En₅₀-₇₀). Enclave opx are characterized by cpx overgrowth. Cpx compositions are more varied within the enclaves, with up to 20 wt% Wo variation. Bulk whole-rock rare earth element concentrations compared to chondrite reveal that fine-grained enclave compositional patterns are not parallel to the trends of the host and coarse-grained enclaves, and glass inclusion analyses reveal a wide range in coarse-grained enclave glass compositions. These data are interpreted and applied to a model of enclave formation at Morne Micotrin. Fine-grained enclaves are likely the result of magma mingling processes, whereas coarse-grained enclaves appear to be formed by hybridization between the Micotrin host andesite and an intruded mafic magma. Continued seismic and gas monitoring of Micotrin may give insight into the timescales of these open-system processes, and allow for a better understanding of the hazards associated with this volcanic center.

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Abstract

This project modeled and analyzed several vertical axis wind turbine designs with the goal of improving performance. The two main turbine designs that were tested are the Savonius and Darrieus turbines. Both are vertical axis designs one operating on the principle of drag the other on the principle of lift. Through research and a series of wind tunnel tests I analyzed the impact of various design variables such as blade number, blade tilt angle, and outer diameter over a range of wind velocities. Goals for the final design included the ability to self start at relatively low wind speeds, and to reduce negative drag during rotation in order to reach high rotational velocities. Although my test results turned out to be inconclusive in determining the relative power and efficiency of my turbine designs, I was able to collect other analytical and observational data. The following report summarizes the design and test procedures I followed, the results found from these tests, and further recommendations for future experimentation.

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This thesis explores how and where natural gas is being utilized in the United States, with the overall purpose of becoming an expert in the field. Natural gas is quickly becoming one of the most important resources in the world. The United States reliance for crude oil from foreign sources has dramatically increased the price and demand for the gas in recent years. As a country we use approximately 23.1 Tcf (trillion cubic feet) of natural gas a year, but that amount still only represents a small portion of the energy consumed by our country per year and is increasing quickly. Due to advancements in modern drilling techniques, such as hydraulic fracture drilling and horizontal drilling, previously unattainable natural gas regions are being drilled. These new techniques have allowed for different shale regions, such as the Marcellus and Haynesville Shale, to be drilled economically, thus decreasing our dependence on other sources. Natural gas is also receiving attention for its use as an alternative fuel source. It is already successfully being used by the NYS Department of Transportation for many of their vehicles. The liquefied form of the gas has also been successfully tested as a fuel source for commercial airliners. In the next few years oil may not be the only primary energy resource of our planet.

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A novel model for measuring the strength of peruoroalkyl acid (PFAA) binding to human serum albumin (HSA) using the protein's native uorescence is described. The model is derived from published properties of HSA and its interactions with other surfactants; it is consistent with these properties and experimental observations. The model's validity has been tested with both medium- to long-chain PFAAs (peruoroheptanoate, peruorooctanoate, peruorononanoate, peruorodecanoate, peruoroundecanoate, peruorohexane sulfonate, and peruorooctane sulfonate) and short-chain PFAAs (peruorohexanoate and peruorobutane sulfonate). These experiments con_rm the model as a valid description for the binding of medium- to long-chain PFAAs to HSA. Results indicate at least 2-3 PFAAs bind to each protein with a_nity on the order of 104 M?1. Binding strengths demonstrate dependence upon peruorocarbon chain length, ionic head group, and protein concentration. The model is not valid for the binding of short-chain PFAAs to HSA. Hill binding coe_cients, uorescence intensity measurements, and wavelengths of maximum emission suggest short-chain PFAAs associate with HSA di_erently and fail to promote the same conformational changes in the protein's tertiary structure as the medium- to long-chain PFAAs.

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Abstract

As the global reservoirs of oil are being depleted, the need for a new fuel source is greatly increasing. The goal of this project was to set up a diesel engine to run on biodiesel in order to gather information on the combustion performance of this fuel. The test engine was fitted with instrumentation to gather data on the pressure within the cylinder and the amount of fuel and air consumed during operation. The data obtained through experimentation will be used to evaluate the useful work output of the engine when running on different biodiesel fuels. This information will be analyzed to determine which biodiesel mixture performs best.

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Abstract

Nuclear magnetic resonance (NMR) spectroscopy is a quintessential non-destructive chemical analytical tool that can provide a wealth of information concerning chemical structure and properties. However, NMR spectroscopy is known for its low sensitivity and resulting weak signal strength. These shortcomings can be further exacerbated when working with biological systems, in the gas phase, or on a micro-volume scale. In this project, para-hydrogen induced polarization (PHIP) was employed to provide greatly enhanced NMR signals in single-scan 1H and 13C-NMR spectroscopy. Simple low-cost methods were developed to provide a continuous flow of para-enriched H2 gas that could be used in both PASADENA (Para-Hydrogen and Synthesis Allow for Dramatically Enhanced Nuclear Alignment) and ALTADENA (Adiabatic Longitudinal Transport After Disassociation Engenders Nuclear Alignment) -type para-hydrogenation experiments. Two principal unsaturated substrate/homogeneous hydrogenation catalyst combinations were employed for investigating PHIP, namely ethyl propiolate/[Rh(cod)(dppb)]BF4 and styrene/Rh[(PPh3)3]Cl. Despite modest reaction yields (?8-10%), 1H-NMR signal enhancements of several orders of magnitude were observed in single-scan NMR spectroscopy. The 1H hyperpolarization in the para-hydrogenation product was transferred to 13C hyperpolarization via a simple field cycling method (diabatic demagnetization followed by adiabatic remagnetization). This was accomplished using a magnetic shield consisting of several concentric layers of ?-metal. This heteronuclear hyperpolarization transfer resulted in dramatically enhanced signals in single-scan 13C-NMR spectroscopy. With the aim of the possible application of these PHIP techniques to magnetic resonance imaging (MRI), preliminary experiments were conducted employing a polymer-bound Rh[(PPh3)3]Cl hydrogenation catalyst to the para-hydrogenation of styrene. Using such a heterogeneous catalyst would allow for simpler catalyst/sample separation techniques when using PHIP methods in biological systems. The polymer bound catalyst proved to be an effective hydrogenation catalyst, but attempts to observe PHIP using this catalyst are still ongoing.

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The purpose of this project was to contribute to the development of aerogel-based automotive catalytic converters. Existing catalytic converters utilize platinum and palladium catalysts to oxidize the carbon monoxide and unburned hydrocarbons in automotive exhaust. However, these noble metals are expensive and environmentally damaging to produce. Aerogels consist of a nanoscale solid lattice surrounded by air. Because of their high surface areas, metal oxide aerogels can catalyze the oxidation of carbon monoxide and hydrocarbons without the use of noble metals. We utilized epoxide proton-scavenging recipes to create alumina and chromia sol gels and xerogels. An alumina epoxide recipe was also combined with Union’s Rapid Supercritical Extraction process in order to fabricate alumina aerogels from non-alkoxide precursors. The aerogels’ surface area was only 171m2/g, considerably lower than the 470m2/g measured for alumina xerogels prepared from the same epoxide recipe. Both materials displayed a highly porous microstructure when imaged with a scanning electron microscope. In addition, a catalytic testing system was designed to measure the aerogels’ and xerogels’ ability to catalyze the oxidation of carbon monoxide and propane. The designed system heats simulated automobile exhaust to temperatures up to 500°C, flows the exhaust through a stainless steel reactor containing the catalytic sample, and determines the composition of the exhaust exiting the reactor using a four gas infrared analyzer. Preliminary testing of the assembled system demonstrated that it is unlikely to leak poisonous CO during testing but can only heat air to a temperature of 300°C in its current configuration.

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The Scandinavian Caledonides are an orogenic belt formed when Baltica collided with Laurentia during the late Silurian to early Devonian (Scandian, ~426-390 Ma, Gee et al., 2008). The thrust sheets forming the belt are divided into the Lower, Middle, Upper, and Uppermost Allochthons derived, respectively, from the Baltican margin and regions progressively farther outboard. This study focuses on the Blåhø Nappe, part of the Middle Allochthon, which is generally presumed to have been from an Early Paleozoic volcanic arc off the Baltican margin. The Blåhø Nappe contains abundant igneous and sedimentary rocks, metamorphosed almost entirely at amphibolite facies, but contains scattered eclogites that indicate prior metamorphism at high pressure. The host amphibolites adjacent to eclogites retain microstructures indicating that the amphibolites originated from retrograded eclogites, and thus were once eclogites themselves. Rocks away from the eclogites, however, have no textural evidence of having been eclogites, and presumably have been retrograded from eclogite and thoroughly recrystallized.\r\n\r\nUsing textural evidence, mineral analyses, and thermodynamic modeling, we studied the conditions under which the host amphibolites transformed from eclogites during tectonic escape from great depth. 41 rock samples, mostly amphibolites from different sites in the Blåhø Nappe, were made into polished thin sections, with mineral assemblages and textures observed with a polarized light microscope. BSE imaging and quantitative analyses (standards-based EDS) were done on selected samples, targeting particular textures and low-variance assemblages. Analyses were modified to fit thermodynamic solution model stoichiometric constraints, and combined as system compositions for thermodynamic modeling with Perple_X. The modal and mineral compositional results were compared across the model T-P space to the mineral modes and compositions given to the model. Where the modal and compositional criteria matched (within uncertainties) was presumed to be the best estimate of the T-P conditions of last equilibration of that assemblage. Multiple samples giving best results at the same T-P conditions gave confidence that those T-P estimates were geologically meaningful. Textural evidence (such as garnet-rimming symplectites and pyroxenes rich in plagioclase inclusions and exsolution lamellae) strongly indicates that the amphibolites were once eclogites themselves. Other workers show that the eclogites formed in T-P conditions of ~550 - 750 °C 15 - 35 kbars. Remnant eclogite retrograde textures in Blåhø Nappe samples apparently record intermediate conditions of ~550 - 800 °C, 7 - 10 kbars. as eclogites recrystallized into amphibolites. Amphibolite matrix apparently deformed and partially reequilibrated at T-P conditions of ~475 - 525 °C, 5-8 kbars. These temperatures and pressures of metamorphism could only be determined by comparing nearby samples, because the complexity of the mineral textures and chemistry (e.g. zoning), made it very difficult to choose apparent equilibrium textures without the models.

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Fraiji et al. determined a binding constant (K) of 581 = 6 M-1 for the 1:1 complex between 2-acetylnaphthalene (2-AN) and ?-cyclodextrin (?-CD) in H20 using fluorescence quenching experiments (Appl. Spectrosc. 1994, 48, 79). Molecular modeling experiments indicate the possibility of complex stabilization resulting from hydrogen bonds between the C=O group of 2-AN and the -OH groups on the rim of ?-CD. To check this possibility, we measured the K of the 2-AN:trimethyl-?-CD (TM-?- CD) complex, where all rim -OH groups are converted to –OCH3. In this case, K decreases to 134 M-1. To show that this is due to reduced hydrogen bonding capability rather than steric influence, the K of 2-AN: ?-CD was measured at high pH. K decreases to 276 M-1 at pH 13.5, and an inflection point is observed at pH 12.2 (which is the pKa of rim -OH groups). Therefore, our experiments confirm the significance of 2-AN carbonyl hydrogen bonding to ?-CD -OH groups. Fluorescence studies were also performed with 1,5-DNSA, 2,6-MANS, and 2,6- TNS. K was 151M-1 for 1,5-DNSA: ?-CD and 105M-1 for 1,5-DNSA:TM-?-CD. The smaller K for the TM-?-CD complex is probably due to steric effects associated with the rim -OCH, groups. Thermodynamic properties of the 2,6-MANS:TM-?-CD complex were investigated. ?H and ?S were calculated as -35 kJ/mol and -47 J/mol K, respectively. Catena and Bright calculated ?H as -6.7 kJ/mol and AS as 50 J/mol K for the 2,6-MANS: ?-CD complex (Anal. Chem. 1989, 61, 915). The methyl groups of the TM-?-CD make the cavity environment more hydrophobic than the natural ? -CD, creating much stronger guest:host interations. The methyl groups also restrict the motion of 2,6-MANS, which overcomes the favored entropic effects of solvent replacement and solvent shell disturbance. The 2,6-TNS:TM-?-CD, K was calculated as 2358 M-1, compared to Catena and Bright's 1980 M-1 for the ?-CD complex. The more hydrophobic cavity of TM-?-CD compensates for the loss of hydrogen bonding between the guest SO3- group and CD rim -OH groups. CE was employed for the separation of LSD (d-lysergic acid diethylamide), LAMPA (D-lysergic acid methylpropylamide) and iso-LSD using several types of cyclodextrins as buffer additives. A sample consisting of LSD, LAMPA, and iso-LSD was partially resolved (R>1) with 60 mM ?-CD in a 50 mM acetate buffer, pH 4.03, at 15°C. Migration times were under 9 min. Another solution consisting of both 60 mM ?-CD and 0.2 mM sulfated-?-CD in 50 mM acetate buffer, pH 4.03, at 25°C provided baseline separation (R> 1.5) of the sample mixture in a similar 9 min. time window. The reproducibility of migration times for both methods was 4-5% between days and 1% on the same day. Partial separation of LSD and LAMPA (R~1) was (observed in a 9 min. time window using 15 mM sulfated-?-CO in a 50 mM borate buffer, pH 8.51 at 25°C. Between day and same day reproducibilities were 2-3% and 1%, respectively.

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The goal of this project was to design and fabricate a system which could deliver artificially created test gas to the heating section at a specified composition, flow rate, and humidity, while additionally simulating the transient conditions found in automobile exhaust. It will make up one subsystem of the Union College Aerogel Lab's second generation catalytic test bed. The test bed will be used to test the viability of catalytic aerogels as three way catalysts for automotive exhaust. To date a system for mixing test based on partial pressure has been fabricated and is operational, a system for generating transient conditions using solenoid valves and two gas mixtures has been designed and the parts sourced, and several viable humidification designs have been evaluated.

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Although it has been shown that the hydrogen exchange rates between the most slowly exchanging amide protons of a protein and the solvent can be used to predict the global thermodynamic stability of a protein, the great majority of amide hydrogens along the backbone of a protein exchange from either partially or fully folded conformations, and their rate of exchange strongly depends upon the environment in that folded state. We are examining the electrostatic and conformational dependence of the hydrogen exchange kinetics of Pseudomonas aeruginosa azurin, which can bind either the diamagnetic Cu(I) or Zn(II) in its active site and Pyrococcus furiosus (Pf) rubredoxin which can be substituted with Zn(II) or Ga(III). Molecular dynamics and electrostatic calculations were used to determine the theoretical hydrogen exchange rates for these metal-substituted proteins in order to assess the relationship between metal ion charge and exchange rate.

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Reliable data on heats of solution of concentrated mixed electrolytes is a rather scarce. This work purports to give formulas for the heat of solution at saturation of an electrolyte in a solution saturated with respect to still another electrolyte. These formulas are in terms of solubility data and non-calorimetric thermodynamic data and are as follows.

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We explore the properties of the hydrosphere on Europa involving both a modeling technique and experimental methods. We perform a computational analysis of the thermodynamic properties for an ideal, pure-water Europan ice shell using a Python programming framework called SeaFreeze. We create four models assuming surface temperatures of either 50 K or 140 K and ice shell thicknesses of either 3 km or 30 km. We observe mostly linear trends for the density and seismic wave velocities with respect to depth and find that surface temperature has the greatest effect on the models. Simultaneously, we experimentally investigate the phase diagram of different saltwater concentrations in an attempt to further constrain the ice shell properties. We determine the freezing temperatures of 5%, 10%, and 20% by-weight NaCl-water solutions under constant pressures from 0 MPa to 70 MPa. We find increasing the salt concentration, the pressure, or both decreases the freezing point temperature with a depression at our most extreme conditions of about -20 °C from that of pure water at zero pressure. Based on our experimental results, we expect that adding NaCl to the pure-water models would lower their ice-water boundary temperatures. Areas of future development include continuing to explore the phase diagrams of different saltwater concentrations, including MgSO₄, KCl, and varying combinations of all three salts, extending the pure-water SeaFreeze models to analyze Europa's subsurface ocean layer, implementing various new techniques to make our experiments more precise, and finally applying our results to the other icy moons, such as Ganymede or Callisto.

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The fact of the instability of lead iodide at moderately high temperatures is well known. This work was undertaken in order to discover, if possible, the degree of dissociation, its change with the temperature, and to collect any other important facts connected with the equilibrium.

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The main goal of this work: was to explore complexes formed between 2-acetylnaphthalene (2-AN) and unsubstituted ?, ?, and y-cyclodextrins as well as 2-An and methylated ?, ? and y-cyclodextrins. The substituted cyclodextrins used were trimethyl-?-cyclodextrin (TM-?-CD), trimethyl-?-cyclodextrin (TM-?-CD), trimethyl-y-cyclodextrin (TM-y-CD), and dimethyl-?-cyclodextrin (DM-?-CD). For the trimethylated cyclodextrins, all three of the -OH groups on the cyclodextrin ring are replaced by -OCH3 groups. The dimethylated cycloextrin on the other hand only has 18 of the 21 -OH groups replaces by -OCH3 groups. Binding constants were determined for complexes using fluorescence quenching experiments at varying temperatures. Thermodynamic parameters of complex formation (?H° and ?S°) were determined for 2-AN with DM-?-CD. Most of the CD's form a 1:1 complex with 2-AN but 1:2 (2-AN:(TM-?-CD)2) and 2:2 complexes are also observed, and no complex is observed for 2-AN with TM-y-CD.

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