Physical Sciences and Mathematics Commons^™

Modified Organoclay Containing Chelating Ligand For Adsorption Of Heavy Metals In Solution., Mary Akuyea Addy

Electronic Theses and Dissertations

Presence of a chelating ligand in the clay structure significantly improves its ability to immobilize heavy metals from contaminated sludge or wastewater. Two-step modification procedure comprising sequential pillaring and grafting of chelating agent to the modified clay is involved.

Montmorillonite and kaolin were chosen as typical examples of expandable and non-expandable clays, correspondingly. Modifications with silica and ferric oxide were targeted on development of mesoporous structure. Laboratory tests of the organoclay efficiency for purification of wastewater were conducted with the most promising sample, i.e. organoclay with the highest specific loading of chelating agent. Experiments were conducted with model wastewater containing …

The Tetrafluoroborate Salt Of 4-Methoxybenzyl N-2-(Dimethylamino)Ethyl-N-Nitrosocarbamate: Synthesis, Crystal Structure And Dft Calculations, Helene Hedian, Vladimir Benin

Chemistry Faculty Publications

The tetrafluoroborate salt of 4-methoxybenzyl N-2-(dimethylamino)ethyl-N-nitrosocarbamate was prepared in two steps, via the corresponding carbamate. Its crystal structure is monoclinic, space group P21/c. The unit cell dimensions are: a = 19.499(8) Å, b = 5.877(3) Å, c = 15.757(7) Å, α = 90°, β = 110.019(7)°, γ = 90°, V = 1696.5(12) Å3, Z = 4. The structure exhibits an unexpected, pseudo-gauche conformation with respect to the C2–C3 bond, due to a stabilizing hydrogen bond between the carbonyl oxygen (O1) and the hydrogen atom at the trialkylammonium center (H3n), with a distance between them of …

Investigating Interfacial Reactions Of Silver-Containing Films Using Novel Methods, Sarah Danielle Pretty

Electronic Thesis and Dissertation Repository

This thesis presents work on the mechanism and kinetics of the surface film reactions involving the conversion of aqueous species on solid surfaces, and specifically, the reactions of iodide and bromide on silver oxide on silver substrate. These reactions provide a method of immobilizing unwanted halides and are particularly suited to control of hazardous radioactive iodine. Potential applications of this research include nuclear reactor safety and post-accident radioiodine management, and the safe production and use of the medical isotope ¹³¹I.

The aqueous-solid conversion of reaction Ag₂O with X^-(aq) to form AgX on a Ag substrate …

The Impact Of Driving Conditions On Phev Battery Performance, Nathan Christensen, John Patten, Steven Srivastava, Gary P. Nola

john a patten

The battery performance of a modified Prius with a 5 kWh plug-in battery was documented for a year to determine the impact of environmental conditions and user attributes on vehicle performance. Both fuel economy and pure electrical efficiency were compared to ambient temperature. The fuel economy has a positive relationship with ambient temperature until approximately 70˚F where the efficiency begins to drop. Electrical performance has a positive linear relationship with ambient temperature. With the emergence of electric vehicles (EVs) and PHEVs from a variety of automotive manufacturers, information on EV and PHEV performance for consumers will become more important.

Concentration Oscillations In The Processes Of Unsaturated Compounds Oxidative Carbonylation. 2. Oxidative Carbonylation Of Alkynes In The Palladium Halogen Complexes Solutions (In Russian), Sergey N. Gorodsky

Sergey N. Gorodsky

No abstract provided.

Preparation And Characterization Of A Composite Of Gold Nanoparticles And Single-Walled Carbon Nanotubes And Its Potential For Heterogeneous Catalysis, Anne Shanahan, James Sullivan, Mary Mcnamara, Hugh Byrne

Articles

A single-walled carbon nanotube-supported gold nanoparticle composite was prepared and characterized by X-ray diffraction, scanning transmission electron microscopy/scanning electron microscopy/transmission electron microscopy, energy-dispersive X-ray analysis, atomic absorption spectroscopy, nitrogen adsorption, Raman spectroscopy, and ultraviolet-visible spectroscopy. The Au particles were found to be crystalline, with a well-defined and narrow particle-size distribution, centered around 7 nm. The activity and selectivity of the composite for solventless aerobic oxidation of a secondary alcohol were examined, and a conversion efficiency of 95% was obtained.

Excellent Adventures In Global Collaboration, Glenn W. "Max" Mcgee, Aracelys Rios

Publications & Research

No abstract provided.

The Vinylguaiacol/Indole Or Vgi ("Veggie") Ratio: Assessing Relative Contributions Of Terrestrial And Aquatic Organic Matter To Sediments, Michael A. Kruge, Kevin K. Olsen, Jaroslaw W. Slusarczyk, Elaine Gomez

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

In studies of the organic matter (OM) fraction of marine, estuarine, fluvial, or lacustrine sediments, one of the most fundamental distinctions to be made is that between terrestrial and aquatic OM. To supplement the parameters commonly used for this purpose (e.g., C/N and stable isotope ratios), we proposed the Vinylguaiacol/Indole or VGI ("Veggie") ratio, defined as [vinylguaiacol / (indole + vinylguaiacol)] using data produced by analytical pyrolysis-gas chromatography/mass spectrometry of dried, homogenized sediment samples [1]. The ratio employs the peak areas of these two compounds on the mass chromatograms of their molecular ions (m/z 150 and 117, respectively). Major pyrolysis …

Concentration Oscillations In The Processes Of Unsaturated Compounds Oxidative Carbonylation. 1. Processes Of Acetylene And Phenylacetylene Oxidative Carbonylation (In Russian), Sergey N. Gorodsky, Katarina Novakovic

Sergey N. Gorodsky

This review describes the processes of oxidative carbonylation of acetylene and phenylacetylene, occurring in the oscillatory mode under conditions of homogeneous catalysis by palladium complexes.

Characterization Of Uranium Species In Sediments Under Iron And Sulfate Reducing Conditions Using Synchrotron-Based Techniques, Don Q. Pham, John Bargar

STAR Program Research Presentations

Uranium is one of the most common and problematic contaminants at legacy Department of Energy sites. Groundwater contamination is particularly problematic because it occurs at depth, is present in large volumes, and cannot be easily accessed for clean-up. One method of remediation being investigated is the bioreduction of soluble U(VI) to insoluble U(IV) complexes through the in-situ stimulation of metal-reducing bacteria. Understanding the structure of these uranium complexes can help us determine their fate and stability in groundwater and map out the biological process of uranium reduction by metal-reducing bacteria. In this study, we used the synchrotron-based techniques, X-ray absorption …

New Nanosystem Mixed Reactor For Urban Wastewater Treatment, Masoud Rastegar, Kamran Rahmati Shadbad

Masoud Rastegar

No abstract provided.

Do Wind Turbines Affect Weather Conditions?: A Case Study In Indiana, Meghan F. Henschen, Brittany Herrholtz, Lacey Rhudy, Kathryn Demchak, Brian Doogs, Joshua Holland, Erik Larson, Johnny Martin, Matthew Rudkin

The Journal of Purdue Undergraduate Research

Wind turbines are becoming increasingly widespread in the United States as the world looks for cleaner sources of energy. Scientists, policymakers, and citizens have strong opinions regarding the positive and negative effects of wind energy projects, and there is a great deal of misinformation about wind energy circulating on the Web and other media sources. The purpose of this study is to gain a better understanding of how the rotation of hundreds of turbines can influence local weather conditions within a wind farm and in the surrounding areas. This experiment measures temperature, atmospheric pressure, wind speed, wind direction, relative humidity, …

Application Of Raman Spectroscopy To Lubricants, Lubricated Surfaces And Lubrication Phenomena, David W. Johnson

Chemistry Faculty Publications

Recent advances in lasers and detector technologies and the development of low-cost instruments and fiber-optic probes have brought about an explosion in the lubrication systems being studied by Raman spectroscopy. This article provides examples of the use of Raman spectroscopy in the study of lubrication phenomena, including the characterization of liquid lubricants, lubricant additives, and solid lubricants; the study of vapor-phase lubrication; and the use of coated nanoparticles as lubricants.

Modelling Of The Adsorption‐Catalytic Processes In The Multi‐Dispersed Bed, Sergey V. Zazhigalov, Natali A. Chumakova, Andrey N. Zagoruiko

Andrey N Zagoruiko

The simulation work is dedicated to the multidispersed adsorption-catalytic packing, consisting of comparatively large pellets (say, 5-10 mm) of the catalyst-adsorbent and of catalytically active micro-fibers with typical thickness of ~10 microns. During the heating at the regeneration stage the micro-fiber catalyst must be heated much more rapidly than adsorbent-catalyst, due to the much higher unit outer surface area improving the heat exchange. When the adsorbent-catalyst temperature is becoming high enough for partial desorption of chemisorbed VOC, the temperature of the micro-fibrous catalyst will be already as high as necessary one for complete oxidation of desorbed VOCs. This theoretical concept …

Process Of Combined Oxidation Of Co And So2 In Waste Gases Of Non‐Ferrous Smelters At Platinum Glass‐Fiber Catalyst, Sergey V. Vanag, Andrey N. Zagoruiko

Andrey N Zagoruiko

The work is dedicated to the development of the efficient catalyst for the oxidation of CO in presence of significant amounts of SO2. It was experimentally shown that the Pt/Zr-Si glas-fiber-based catalyst is capable to provide complete CO conversion in SO2 presence at temperatures less 300 С, at the same time showing high resistance to deactivation. Application of such catalyst in the reverse-process will allow to raise essentially efficiency of purification of waste metallurgical gases from SO2 under presence of significant amounts (up to 1-2% vol.) of CO.

New Developments In The Area Of Nonstationary And Sorption-Enhanced Catalytic Processes, Andrey N. Zagoruiko

Andrey N Zagoruiko

The presentation is dedicated to catalytic processes performed under artificially created catalyst nonstationarity. It is shown that the highest technological effect can be achieved for a controlled combination of the thermal nonstationarity with the composition nonstationarity of the catalyst surface. Prospective for application of unsteady catalytic and sorption-catalytic processes are analyzed for different case applications: VOC incineration, hydrogen production by steam conversion of hydrocarbons and organic feedsctock, selective anaerobic oxidation of hydrocarbons. In general, unsteady state and sorption-catalytic ideology discovers new degrees of freedom for process development and may become the basement for new generation of highly-efficient catalytic technologies in …

Determination Of Selected Heavy Metals In Some Creeks In A Tennessee City., Ann Ejimole Item

Electronic Theses and Dissertations

Concentrations of Ni, Cu, Zn, Fe, Cd, and Pb were determined in six different creeks within a city in Tennessee using Atomic Absorption Spectrophotometer. Mean concentrations of Ni, Cu, Zn, Cd, Pb, and Fe in the sites examined reveal that they exceed the USEPA recommended limits. High concentrations of Cu (0.130 mg/L), Zn (13.7 mg/L), Ni (0.267 mg/L), and Cd (0.010 mg/L) were observed in site B and Fe (3.01 mg/L) in site E relative to other sites. The concentration of Pb (0.795 mg/l) was higher in site A. Higher concentrations of Cu, Zn, and Fe were detected in samples …

Surface-Enhanced Raman Scattering: Substrate Development And Applications In Analytical Detection, Deepak Bhandari

Doctoral Dissertations

To advance the capabilities of surface-enhanced Raman scattering (SERS), we developed a silver modified polypropylene filter (AgPPF) substrate which acts as a pseudo stationary phase in harvesting SERS signatures of so called "phytochemical estrogens" and other environmentally significant chemicals. To augment electron beam lithography (EBL) in SERS research, we also introduced an interesting nanotransfer printing (nTP) technique which could circumvent the low throughput and extremely high resolution (< 10 nm) limitations of EBL in designing advanced SERS substrates. In our study, a nominal average thickness of 10 nm silver on the polypropylene microfiber produced nanoglobules of less than 100 nm in diameter. This noble metal nanoroughened layer allowed AgPPF to serve as a SERS active substrate, onto which the noted endocrine disrupting chemicals were passed through and harvested. The intense, multifeatured vibrational Raman spectra of very rarely SERS studied chemical species collected indicates the potential for useful detection via this approach of creating SERS substrates. AgPPF substrates were also used in characterizing the adsorption behavior of hydroxyl complexes of uranium. Interestingly, hydroxyl group on the uranium complexes showed slow sorption kinetics on the nanostructured silver surfaces. Understanding the adsorption behavior of aqueous solution of uranium on nanostructured silver surfaces has opened up the possibilities of SERS detection of these environmental and non-proliferation concerned species without any surface modifications. nTP is a high resolution printing technique and relies on interfacial chemistries to control the transfer of thin metal film from a "stamp" to a "substrate". In our research, high-aspect-ratio AutoCAD designed nanopatterns were created on silicon wafers using e-beam lithography and reactive ion etching. Silicon relief pillars based stamps were then used to integrate a variety of nanostructures on different dielectric materials. Thus created nanopatterns have shown their promise to hold their inherent SERS activity. For its simplicity, cost-effectiveness, and ease of operation, this hyphenated nTP-SERS technique is impressive in the selection of suitable supporting-films for better SERS enhancements and also to manipulate gap between nanodiscs (gap-plasmonic SERS effect).

Approach To Arsenic And Selenium Removal From Fly Ash By Oxalate And Estimation Of Calcium Effects On Both Elements, Ying Wen

Masters Theses & Specialist Projects

An approach to arsenic and selenium removal from fly ash is studied. This research includes a comparison of the leaching ability of ammonium oxalate, ammonium citrate, ammonium nitrate and EDTA to extract arsenic and selenium; use of common agricultural waste as a source of oxalate anion to remove arsenic and selenium from fly ash and estimation of additional calcium effects on arsenic and selenium leaching behaviors.
This research shows that extraction strength order is EDTA > ammonium oxalate > ammonium citrate > ammonium nitrate > water, achieving arsenic extraction efficiencies of 94.18%, 84.17%, 4.50%, 2.89% and 0.18%, respectively; achieving selenium extraction efficiencies of 96.14%, …

Determining The Lon-Exchange Mechanism Of Strontium Into A Niobium Doped Titanosilicate, Samantha Jane Kramer

Masters Theses & Specialist Projects

A 25% niobium substituted sitinakite was exchanged with strontium as time resolved X-ray diffraction data was collected. The structural modeling of this data by Rietveld method1 has lead to the determination of the atomic positions of the ions and unit cell parameters as strontium occupancy increases.

The starting material of the exchange experiment is the protonated phase, H2Nb0.67Ti1.33SiO7·1.9 H2O, with space group P42/mcm2,3. Once strontium (Sr2+) enters the unit cell, extra-framework H2O molecules shift to provide the necessary hydration coordination. These new positions of H2O result in a lowering of symmetry to the P-42m space group, and it is thought …

An Assessment Of Stable Hydrogen-Isotope Analysis Methods To Assign Geographic Origin To Migratory Red-Tailed Hawks (Buteo Jamaicensis), Carla Marie Ahlschwede

Department of Environmental Studies: Undergraduate Student Theses

Stable-hydrogen isotopes are becoming an increasingly popular method of studying migratory birds, though sample preparation methods may affect results. In this study I examined feathers from red-tailed hawks (Buteo jamaicensis) to determine the relationship between measure of δD due to inter-feather variation or drying methods, assessed the accuracy of results by using two birds of known-origin and estimated possible natal origins of migratory red-tailed hawks. Two feathers per individual were taken from 81 wild hawks caught at Hitchcock Nature Center near Crescent IA and from 2 rescued red-tailed hawks, Raptor Recovery Nebraska near Eagle, NE. 119 of the …

Energy Densification Via Hydrothermal Carbonization, Keri Noack

Festival of Communities: UG Symposium (Posters)

A process called hydrothermal carbonization (HTC), also known as wet torrefaction involves treatment of raw biomass in hot, pressurized water. HTC of woody biomass has been shown to significantly increase the energy density of the feedstock, producing a biochar, similar to coal, having up to 40% higher calorific energy content. Feedstocks investigated include Tahoe chips, Pinion/Juniper chips, Rice hulls, and Corn Stover pellets pre-treated at 215 °C, 255 °C, and 295 °C. Chemical analyses were conducted on the gaseous, aqueous, and solid HTC products. Energy contents of the solid biochar products were measured by calorimetry, and mass balances were determined.

Spectroscopic (Ir, Nmr, Uv-Vis), Theoretical Study And Optical Properties Of 9,10-Dihydrobenzo(A)Pyrene-7(8h)-One And 7, 8, 9, 10-Tetrahydrobenzo(A)Pyrene, Mireya Martinez

Undergraduate Research Conference

Polycyclic aromatic hydrocarbons (PAHs) are organic molecules found in the environment. The PAHs are formed from incomplete combustion, are found in diesel exhaust particles, grilled foods, gas burners, emission from wood, and cigarette smoke. These compounds are known to be carcinogenic and mutagenic1,2. Spectroscopic studies were performed on two PAHs, 9,10- dihydrobenzo(a) pyrene-7(8H)-one and 7,8,9,10- tetrahydrobenzo(a)pyrene, which helped to characterize them. Also, a theoretical infrared study was done on 9,10-H2BaP, a scaling factor was found for a simulated infrared spectrum.

A Sodium Salt Of The Dimer Of Boronoterephthalic Acid Anhydride, Scott Simmons, Albert Fratini, Vladimir Benin

Chemistry Faculty Publications

The title compound, sodium bis­(6-carb­oxy-1-hy­droxy-3-oxo-1,3-dihydro-2,1-benzoxaborol-1-yl)oxidanium, Na+·C16H15B2O13-, was prepared in two steps from 2-bromo-p-xylene. Its crystal structure was determined at 140 K and has triclinic (P) symmetry. The compound presents a unique structural motif, including two units of the cyclic anhydride of boronoterephthalic acid, joined by a protonated, and thereby trivalent, oxonium center. Association in the crystal is realized by complementary hydrogen bonding of the carboxyl groups, as well as by coordination of the sodium cations to the oxygen centers on the five-membered rings.

Theoretical Investigation Of A Reported Antibiotic From The 'Miracle Tree' Moringa Oleifera, Michael Horwath, Vladimir Benin

Chemistry Faculty Publications

Moringa oleifera, sometimes called the “Miracle Tree,” has received international attention for its potential to improve health in impoverished tropical areas. In addition to high vitamin content in the leaves and pods, the tree contains compounds with antioxidant and antibacterial properties. This study focused on the theoretical investigation of the suggested structure of one antibacterial compound, “pterygospermin,” whose existence was proposed after some studies of the roots of M. oleifera. The structure of pterygospermin was first proposed by a research group working in the 1950s, but later studies have not found evidence of this compound and have instead …

Evaluation Of The Sensitivity Of Inventory And Monitoring National Parks To Nutrient Enrichment Effects From Atmospheric Nitrogen Deposition Northern Great Plains Network (Ngpn), T. J. Sullivan, T. C. Mcdonnell, G. T. Mcpherson, S. D. Mackey, D. Moore

United States National Park Service: Publications

Northern Great Plains Network (NGPN)

National maps of atmospheric N emissions and deposition are provided in Maps A and B as context for subsequent network data presentations. Map A shows county level emissions of total N for the year 2002. Map B shows total N deposition, again for the year 2002.

There are three parks in the Northern Great Plains Network that are larger than 100 square miles: Badlands (BADL), Missouri (MNRR), and Theodore Roosevelt (THRO). In addition, there are 10 other smaller parks.

Total annual N emissions, by county, are shown in Map C for lands in and surrounding …

Institute Overview, Morton Sternheim

STEM Digital

Digital cameras and computers are widely available for students and teachers. However, they are mainly used for documentation: creating PPT presentations, handouts, posters, etc. STEM DIGITAL shows how digital image analysis can be applied to environmental (and other) research in STEM courses. Application to studies of air quality, water quality, arsenic contamination, climate change, diffusion, etc.

Digital Camera Basics, Stephen Schneider

STEM Digital

No abstract provided.

Measuring Lengths And Areas With Adi. Student Guide, Morton Sternheim

STEM Digital

No abstract provided.

Measuring G With Movie Tracker, Stephen Schneider

STEM Digital

No abstract provided.