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Towards The Asymmetric Synthesis Of Ascochlorin, Özdemi̇r Doğan, Wolfgang Oppolzer Jan 2001

Towards The Asymmetric Synthesis Of Ascochlorin, Özdemi̇r Doğan, Wolfgang Oppolzer

Turkish Journal of Chemistry

A synthetic approach is described to the asymmetric synthesis of ascochlorin (1), an antiviral antibiotic, based on the construction of a sesquiterpene unit via asymmetric Diels-Alder reaction of tigloyl sultam 4 & butadiene, and the introduction of the aromatic side chain (C9-C12 unit) by employing cuprate chemistry.


Evaluation Of Sample Pre-Treatment Procedures For The Determination Of Cr, Ni And V In Biological Matrices By Etaas, Jan Medved, Jana Kubova, Eva Chmielewska, Vladimir Stresko Jan 2001

Evaluation Of Sample Pre-Treatment Procedures For The Determination Of Cr, Ni And V In Biological Matrices By Etaas, Jan Medved, Jana Kubova, Eva Chmielewska, Vladimir Stresko

Turkish Journal of Chemistry

Electrothermal atomic absorption spectrometry (ETAAS) was applied for the determination of chromium, nickel and vanadium in biological materials (earthworms, feather, lucerne). Three different decomposition procedures of biological matrices are presented. The utilization of NH_4H_2PO_4, Mg(NO_3)_2 and Pd(NO_3)_2+ Mg(NO_3)_2 as chemical modifiers are investigated and compared. Optimal temperature conditions for the electrothermal determination of Cr, Ni and V are selected. Precision of the determination expressed as relative standard deviations for Cr, Ni and V varied from 6 to 22% . The detection limits are for Cr 8 \\mu g kg^{ - 1}, Ni 12 \\mu g kg^{ - 1}, and V …


Characterization Of Lipids And Fatty Acid Methyl Ester Contents In Leaves And Roots Of Crocus Vallicola, Nuretti̇n Yayli, Zerri̇n Kiran, Hasan Seymen, Hasan Genç, Mustafa Küçüki̇slamoğlu Jan 2001

Characterization Of Lipids And Fatty Acid Methyl Ester Contents In Leaves And Roots Of Crocus Vallicola, Nuretti̇n Yayli, Zerri̇n Kiran, Hasan Seymen, Hasan Genç, Mustafa Küçüki̇slamoğlu

Turkish Journal of Chemistry

The chemical composition of the fatty acids methyl esters (FAMEs) and other lipids in leaves and roots of Crocusvallicola were analyzed by gas chromatography-mass spectrometry(GC-MS). In this work, twenty-eight compounds, including 22 FAMEs, 1 aldehyde, 3 hydrocarbons (substitute alkane and alkene), 2 alcohols in the leaves and twenty-one compounds (17 FAMEs, 1 anhydride, 1 substitute alcohol, 1 ketone, 1 substitute amide) in the roots were identified by GC-MS from C. vallicola. The FAMEs in leaves and roots were highly similar; only the amounts of the esters were different. Key Words: Crocus vallicola, leaves, roots, FAMEs


Calculation Of Multi-Center Integrals For The Region Of Moderate And Weak Overlap, Abdulhali̇k Karabulut, Gökhan Budak, Lütfü Demi̇r, Nagi̇f Sefteroğlu Nabi̇yev, Yusuf Şahi̇n Jan 2001

Calculation Of Multi-Center Integrals For The Region Of Moderate And Weak Overlap, Abdulhali̇k Karabulut, Gökhan Budak, Lütfü Demi̇r, Nagi̇f Sefteroğlu Nabi̇yev, Yusuf Şahi̇n

Turkish Journal of Chemistry

In this study a general formula was established for multi-center integrals over Gaussian basis sets using the two-center expansion of nuclear attraction and electron repulsion potentials. The terms of the formula are the analytical functions of interatomic distances. Three kinds of integrals contained in these formulae can be evaluated analytically. In the presented method, unlike many other popular methods, the numerical integrations procedure is unnecessary since it does not contain the incomplete gamma function. A computer program was written and tested for various orbitals. The calculations show that the series converge very rapidly.


The Influence Of Transition Metal Ions On The Kinetics Of Ascorbic Acid Oxidation By Methylene Blue In Strongly Acidic Media, M. Nasiruddin Khan, Anila Sarwar Jan 2001

The Influence Of Transition Metal Ions On The Kinetics Of Ascorbic Acid Oxidation By Methylene Blue In Strongly Acidic Media, M. Nasiruddin Khan, Anila Sarwar

Turkish Journal of Chemistry

The kinetics of the oxidation of L-ascorbic acid (H_{2} A) by methylene blue was investigated in strongly acidic media over the temperature range 22-40 ^oC. The kinetic studies were carried out as a function of different variables like concentration, pH, ionic strength and temperature. The rate was found to be a linear relation with [H_{2} A], [M.B.] and [H^{+}]. Ionic strength dependence formation indicated complex formation by monocationic and anionic species in solution. The reaction rate was greatly catalyzed by the presence of trace amounts of copper (II) ion. Possible mechanisms for the catalyzed and uncatalyzed reactions are proposed. Kinetic …


Synthesis And Spectrophotometric Investigation Of A New Vic-Dioxime Ligand And Its Transition Metal Complexes, Mustafa Dolaz, Mehmet Tümer, Ayşegül Gölcü, Selahatti̇n Seri̇n Jan 2001

Synthesis And Spectrophotometric Investigation Of A New Vic-Dioxime Ligand And Its Transition Metal Complexes, Mustafa Dolaz, Mehmet Tümer, Ayşegül Gölcü, Selahatti̇n Seri̇n

Turkish Journal of Chemistry

A new vic-dioxime ligand and its Cu(II), Co(II), Ni(II), Pd(II), VO(IV) and Zn(II) complexes have been prepared and characterized by elemental analyses, infrared, electronic spectra, magnetic moment and molar conductance data. The Ni(II), Pd(II) and Zn(II) complexes have a diamagnetic character. The ^{1}H- and ^{13}C-nmr and GC/MS spectra of the vic-dioxime ligand and its Ni(II), Pd(II) and Zn(II) complexes were recorded. In addition, all compounds are non-electrolyte.


New Photochemical And Electrochemical Methods For The Degradation Of Pesticides In Aqueous Media. Environmental Applications, J. J. Aaron, Mehmet A. Oturan Jan 2001

New Photochemical And Electrochemical Methods For The Degradation Of Pesticides In Aqueous Media. Environmental Applications, J. J. Aaron, Mehmet A. Oturan

Turkish Journal of Chemistry

The development of new electrochemical and photochemical methods for the decontamination of natural water containing significant concentrations of aromatic pesticides is described. The electrochemical method is based on the electro-Fenton process, i.e. the simultaneous reduction of O_{2} and Fe^{3+} ions. Hydroxyl (OH^{.}) radicals are electrosynthesized in aqueous solutions, followed by complete mineralization of the initial pollutants. The photochemical methods involve either a direct photodegradation reaction of pesticides by UV light, or indirect photodegradation processes including H_{2}O_{2} photolysis or photo-Fenton reagents (H_{2}O_{2}/ Fe^{3+} ). Examples of the application of these methods to chlorophenoxy acid herbicides and four aromatic pesticides (bendiocarb, pirimiphos-methyl, …


A Preliminary Assessment Of Tidal Flooding Along The New Hampshire Coast: Past, Present And Future, Larry G. Ward, Jamie R. Adams Jan 2001

A Preliminary Assessment Of Tidal Flooding Along The New Hampshire Coast: Past, Present And Future, Larry G. Ward, Jamie R. Adams

Faculty Publications

This report presents the results of a preliminary study that examines several critical coastal issues for New Hampshire including sea level fluctuations (past, present and future), shoreline migrations, and tidal flooding. Included are: 1) an analysis of sea level changes over the Holocene and resulting shoreline migrations, 2) an assessment of low-lying areas with elevations below selected tidal flooding datums in coastal areas, and 3) an assessment of increases in low-lying areas that are potentially at risk to tidal flooding over the next century due to sea level rise.


Probing The Capabilities Of Copper Complexes With Nitrogen And Sulfur Containing Macrocyclic Ligands As Aziridination Catalysts, Jonathan Natkin Jan 2001

Probing The Capabilities Of Copper Complexes With Nitrogen And Sulfur Containing Macrocyclic Ligands As Aziridination Catalysts, Jonathan Natkin

Honors Theses

Aziridines are three-membered rings containing one nitrogen atom. They are useful as synthetic intermediates in many organic reactions. Much work has been devoted to synthesizing their analogs, cyclopropanes and epoxides, but little work has been done on the aziridination reaction. This study endeavored to probe the efficiencies of novel copper aziridination catalysts with N3 and S3 macrocyclic ligands compared to an NS2 analog for the reaction with the nitrene precursor (N-(paratosylsulfonyl) imino)phenyliodinane, PhINTs, and the olefin styrene. The nitrogen containing catalyst complex gave higher yields than the sulfur containing catalyst complex. Both ligands were found to decrease the yield of …


Photochemical Degradation Of 2,4-D And Atrazine In Well-Defined Media, Asher D. Ghertner Jan 2001

Photochemical Degradation Of 2,4-D And Atrazine In Well-Defined Media, Asher D. Ghertner

Honors Theses

Atrazine and 2,4-D are common herbicides used for crop, lawn, and rangeland management. Photochemical degradation has been proposed as one safe and efficient remediation strategy for both 2,4-D and Atrazine. In the presence of iron(llI) and hydrogen peroxide these herbicides decay by both thermal and light induced oxidation. Past studies have focused primarily on sun light as an energy source. This work provides a mechanistic description of herbicide degradation incorporating intermediate degradation products produced in the dark and under well-defined light conditions.


Study Of The Effects Of Co2(G) On The Fe(Ii)-Luminol Chemiluminescence System: Application To Ultra-Trace Analysis Of Fe(Ii), Sara Beth Lovitz Jan 2001

Study Of The Effects Of Co2(G) On The Fe(Ii)-Luminol Chemiluminescence System: Application To Ultra-Trace Analysis Of Fe(Ii), Sara Beth Lovitz

Honors Theses

The Fe(II)-catalyzed oxidation of luminol has been a well-accepted chemiluminescence method for the trace and ultra-trace analysis of Fe(II) and Fe(III) in natural waters. Investigation into this chemiluminescence system has shown that COlg) is essential to Fe-catalyzed luminol chemiluminescence. In absence of CO2(g) there is no chemiluminescent signal. These reactions worked well in the past because CO2 is present in most laboratory H20 supplies. Intentional saturation of CO2 results in a 5-fold increase for this conventional system. We propose a mechanism for CO 2(g) enhancement that includes formation of a CO2-superoxide intermediate, which serves as the oxidant of luminol to …


Exploratory Chemistry In Route To Aromatic Natural Products, Nicholas P. Bizier Jan 2001

Exploratory Chemistry In Route To Aromatic Natural Products, Nicholas P. Bizier

Honors Theses

The focus of this research was the synthesis of two natural products, 1-methyl-s-(1,2,2-trimethy1cyclopentyl)-benzene (formally cuparene), and 3-(1,2dimethylcyclopenty1)-5-methylbenzene-l,2-diol (formally herbertene diol). Cuparene possesses anti-fungal and anti-arthritic properties. This molecule has been the target of a number of syntheses. Herbertene diol, a natural product itself, represents one retrosynthetic step back from mastigophorane; a compound isolated form the liverwort Mastigophora diaclolades. Mastigophorane has been shown to have neural network forming capabilities and has warranted complete synthetic efforts. Through the same chemistry involve in the formation of cuparene, we sought a route to herbertene diol in two steps. We report a successful route to …


Secure Multi-Party Computation Problems And Their Applications: A Review And Open Problems, Wenliang Du, Mikhail J. Atallah Jan 2001

Secure Multi-Party Computation Problems And Their Applications: A Review And Open Problems, Wenliang Du, Mikhail J. Atallah

Electrical Engineering and Computer Science - All Scholarship

The growth of the Internet has triggered tremendous opportunities for cooperative computation, where people are jointly conducting computation tasks based on the private inputs they each supplies. These computations could occur between mutually untrusted parties, or even between competitors. For example, customers might send to a remote database queries that contain private information; two competing financial organizations might jointly invest in a project that must satisfy both organizations' private and valuable constraints, and so on. Today, to conduct such computations, one entity must usually know the inputs from all the participants; however if nobody can be trusted enough to know …


Test 1794: White 8710 Also Agco Allis 9775 (Cummins Engine) Also Agco Dt200, Nebraska Tractor Test Lab Jan 2001

Test 1794: White 8710 Also Agco Allis 9775 (Cummins Engine) Also Agco Dt200, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Tractor Test 1780a: White 8785, Nebraska Tractor Test Lab Jan 2001

Tractor Test 1780a: White 8785, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 1792: Massey Ferguson 2210 Diesel 15-Speed, Nebraska Tractor Test Lab Jan 2001

Test 1792: Massey Ferguson 2210 Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Nebraska Summary 389: Fendt 920 Vario Diesel, Nebraska Tractor Test Lab Jan 2001

Nebraska Summary 389: Fendt 920 Vario Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Nebraska Summary 390: Fendt 924 Vario Diesel, Nebraska Tractor Test Lab Jan 2001

Nebraska Summary 390: Fendt 924 Vario Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Nebraska Summary 391: Fendt 926 Vario Diesel, Nebraska Tractor Test Lab Jan 2001

Nebraska Summary 391: Fendt 926 Vario Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend Jan 2001

Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend

Peer Reviewed Publications

The Pigeon River drains a 16,765-ha agricultural watershed in western Ottawa County, Michigan and discharges into south-central Lake Michigan. Extensive areas of wetlands in the upper watershed were drained in the 1920s, causing significantly altered hydrology characteristics by flashy discharges during storms and periods of snowmelt. We studied stream chemistry and hydrology for a four-year period between September, 1996, and October, 2000, to determine water quality status, to estimate annual nutrient exports, and to evaluate the effects of different seasonal flow types. Results of our study confirmed that the upper reaches of the Pigeon River experience chronically degraded water quality, …


Wetland Vegetation Monitoring, 2000/2001 (Salinity Action Plan), B. Franke, R. Gurner, R. Froend Jan 2001

Wetland Vegetation Monitoring, 2000/2001 (Salinity Action Plan), B. Franke, R. Gurner, R. Froend

Research outputs pre 2011

This report represents the vegetation component of a project designed to provide ongoing monitoring of wetland salinity and biological resources in wetlands of the agricultural zone of south-west Western Australia. Maintenance of wetland biological diversity in the agricultural zone is one of the major objectives of the Salinity Action Plan. Due to their low position in the landscape, wetlands are the habitat most affected by salinisation.


2001 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie Jan 2001

2001 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 2001.


Increased Severity Of Hsv-1 Keratitis And Mortality In Mice Lacking The 2–5a-Dependent Rnase L Gene, Xiaodong Zheng, Robert H. Silverman, Aimin Zhou, Tomoko Goto, Byoung Se Kwon, Herbert E. Kaufman, James M. Hill Jan 2001

Increased Severity Of Hsv-1 Keratitis And Mortality In Mice Lacking The 2–5a-Dependent Rnase L Gene, Xiaodong Zheng, Robert H. Silverman, Aimin Zhou, Tomoko Goto, Byoung Se Kwon, Herbert E. Kaufman, James M. Hill

Chemistry Faculty Publications

Purpose: The2′,5′-oligoadenylate-dependent RNase L gene functions in the interferon-inducible RNA decay pathway known as the 2–5A system. The purpose of this study was to determine whether the absence of this gene affects the pathogenesis of herpes simplex virus type 1 (HSV-1) ocular infection in the mouse. Methods: HSV-1 (strain McKrae) was applied bilaterally to unscarified corneas of RNase L–null mice and congenic controls. To evaluate the severity of herpetic keratitis, slit lamp examinations (SLE) were performed every other day for 14 days. To study corneal histology and apoptosis, HSV-1–inoculated RNase-L-null and congenic control mice, as well as mock-inoculated mice (apoptosis …


Analysis Of Wine For Penicillin, Gary Morris, James Yuan, Roy Williams Jan 2001

Analysis Of Wine For Penicillin, Gary Morris, James Yuan, Roy Williams

Chemistry & Biochemistry Faculty Publications

This study addresses the question of whether the antibiotic Penicillin, which is produced by the common mold Penicillium notatum, could possibly become a contaminate of wine during the fermentation process. The significance of this study is related to the potential health effects this agent might produce in those consumers who have an allergic response to Penicillin. It has been estimated that between 6% and 8% of the American population is subject to this type of allergic response. A method is developed for the detection of penicillin in wines using high-pressure liquid chromatography. We demonstrate that penicillin G hydrolyzes rapidly …


Meso-1, 2-Bis (Methylazo)-1, 2-Diphenylethane, Craig A. Bayse, Barry K. Carpenter, Rudy L. Luck Jan 2001

Meso-1, 2-Bis (Methylazo)-1, 2-Diphenylethane, Craig A. Bayse, Barry K. Carpenter, Rudy L. Luck

Chemistry & Biochemistry Faculty Publications

The title compound, meso-1,2-bis(methyldiazenyl)-1,2-diphenylethane, C16H18N4, is arranged in a disordered manner around an inversion point. The N—N atom distances in the azo group of 1.192 (8) and 1.195 (8) Å, and the C—C atom distances in the ethylene moiety at 1.512 (8) and 1.503 (8) Å in the two models [refined to 51.7 (6) and 48.3 (6)% occupancies] were not significantly different.


Classification And Identification Of Pfiesteria And Pfiesteria-Like Species, Karen Steidinger, Jan Landsberg, R. William Richardson, Earnest Truby, Barbara Blakesley, Paula Scott, Patricia Tester, Torstein Tengs, Patrice Mason, Stever Morton, David Seaborn, Wayne Litaker, Kimberly Reece, David Oldach, Leonard Haas, Gerardo Vasta Jan 2001

Classification And Identification Of Pfiesteria And Pfiesteria-Like Species, Karen Steidinger, Jan Landsberg, R. William Richardson, Earnest Truby, Barbara Blakesley, Paula Scott, Patricia Tester, Torstein Tengs, Patrice Mason, Stever Morton, David Seaborn, Wayne Litaker, Kimberly Reece, David Oldach, Leonard Haas, Gerardo Vasta

Biological Sciences Faculty Publications

Dinoflagellates can be classified both botanically and zoologically; however, they are typically put in the botanical division Pyrrhophyta. As a group they appear most related to the protistan ciliates and apicomplexans at the ultrastructure level. Within the Pyrrhophyta are both unarmored and armored forms of the dominant, motile flagellated stage. Unarmored dinoflagellates do not have thecal or wall plates arranged in specific series, whereas armored species have plates that vary in thickness but are specific in number and arrangement. In armored dinoflagellates, the plate pattern and tabulation is a diagnostic character at the family, subfamily, and even genus levels. In …


Nested Balanced Incomplete Block Designs, J. P. Morgan, D. A. Preece, D. H. Rees Jan 2001

Nested Balanced Incomplete Block Designs, J. P. Morgan, D. A. Preece, D. H. Rees

Mathematics & Statistics Faculty Publications

If the blocks of a balanced incomplete block design (BIBD) with v treatments and with parameters (v; b1;r;k1) are each partitioned into sub-blocks of size k2, and the b2 =b1k1=k2 sub-blocks themselves constitute a BIBD with parameters (v; b2;r;k2), then the system of blocks, sub-blocks and treatments is, by de4nition, a nested BIBD (NBIBD). Whist tournaments are special types of NBIBD with k1 =2k2= 4. Although NBIBDs were introduced in the statistical literature in 1967 and have subsequently received occasional attention there, …


Observations Of Apan During Texaqs 2000, James M. Roberts, Frank Flocke, Andrew Weinheimer, Hiroshi Tanimoto, Bertram T. Jobson, Daniel Riemer, Eric Apel, Elliot Atlas, Stephen G. Donnelly Ph.D., Verity Stroud, Kristen Johnson, Rachel Weaver, Fredrick C. Fehsenfeld Jan 2001

Observations Of Apan During Texaqs 2000, James M. Roberts, Frank Flocke, Andrew Weinheimer, Hiroshi Tanimoto, Bertram T. Jobson, Daniel Riemer, Eric Apel, Elliot Atlas, Stephen G. Donnelly Ph.D., Verity Stroud, Kristen Johnson, Rachel Weaver, Fredrick C. Fehsenfeld

Chemistry Faculty Publications

Measurements of peroxycarboxylic nitric anhydrides (PANs) made in Houston, Texas during TexAQS (Texas Air Quality Study) 2000 showed a relatively abundant PAN compound that had not been identified in previous studies in North America [cf. Williams et al., 2000]. This compound was hypothesized to be peroxyacrylic nitric anhydride { CH2=CHC(O)OONO2, APAN} based on the work of Tanimoto and Akimoto, [2001]. APAN was synthesized and characterized on one of the two GC systems used to make those measurements, subsequent to the TexAQS 2000 field study, confirming that APAN was observed during TexAQS 2000, both on the ground and in airborne measurements. …


Spatial Assessment Of Nonpoint Phosphorus Sources Using Streambed Sediment Monitoring In The Kings River Basin, Nw Arkansas, Jason W. White Jan 2001

Spatial Assessment Of Nonpoint Phosphorus Sources Using Streambed Sediment Monitoring In The Kings River Basin, Nw Arkansas, Jason W. White

Graduate Theses/Dissertations

This study of the Kings River Basin provides a watershed-scale assessment of streambed sediment-Phosphorus (P) and its sources on the landscape. The Kings River drains into Table Rock Lake where surface algal blooms have concerned water scientists and disrupted summer tourism. There are questions about how sediment loads, widespread poultry and cattle operations, and sewage treatment plants are affecting water quality. Previous water quality studies across the U.S. have generally evaluated watercolurnn P. In contrast, few studies have used streambed sediment monitoring to detect P levels at a watershed-scale, and none have been attempted in the Kings River Basin. Sediment …


Kinetics Of Proteolyic Enzymes Monitored Online With Mass Spectrometry, Jennifer L. Rutherford Jan 2001

Kinetics Of Proteolyic Enzymes Monitored Online With Mass Spectrometry, Jennifer L. Rutherford

Theses, Dissertations and Capstones

On-line reaction monitoring using electrospray ionization mass spectrometry was investigated with the goal of kinetically distinguishing the isomeric amino acids leucine and isoleucine. Leucine and isoleucine are isomers of identical mass (113.0946 Da) which are impossible to distinguish by their mass-to-charge ratios. These isomers are a source of ambiguity when sequencing peptides with exoproteases and mass spectrometry. Here we investigated the kinetics of on-line enzymatic reactions involving exoproteases for differentiating between leucine and isoleucine.

The kinetics of the stepwise exopeptidase degradation of 12 leucine/isoleucine isomeric peptides was monitored in real-time with a Finnigan Mat LCQ with an electrospray ionization source. …