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Articles 841 - 870 of 2077
Full-Text Articles in Physical Sciences and Mathematics
The Synthesis Of 2-Indenylphenols: Potential Ligands For Transition Metals, Yoon Jae Kim
The Synthesis Of 2-Indenylphenols: Potential Ligands For Transition Metals, Yoon Jae Kim
Masters Theses
The syntheses of 2-(2-indenyl)-phenol and 2-(1-indenyl)-phenol via a three-step sequence have been developed. In the first steps of the sequence, a Grignard reagent formed from 2-iodoanisole or 2-bromoanisole reacted with 1-indanone or 2-indanone in yields that ranged from 11.3% to 67.2%. The second step consisted of acid-catalyzed dehydration of the alcohol formed in step 1 to make a 2-inenyl anisole; yields in the second step were 45.2% to nearly quantitative. Finally, demethylation of the 2-indenyl anisole was achieved with AlBr3 in ethanethiol in yields ranging from 52.9% to 0 %. Each product was characterized by 1H and 13 …
Eustasy Determination From Borehole Data, Onshore New Jersey: New Boreholes And New Porosity Estimates, William Alan Van Sickel
Eustasy Determination From Borehole Data, Onshore New Jersey: New Boreholes And New Porosity Estimates, William Alan Van Sickel
Masters Theses
Backstripping analysis of detailed stratigraphic data from the Bass River and Ancora boreholes on the New Jersey Coastal Plain (Ocean Drilling Project Leg 17 4AX) was conducted to test and refine previous eustatic estimates (Kominz et al., 1998) and provide new Upper Cretaceous estimates. Porositydepth relationships required by the backstripping method were estimated to supplement those from the Cost B-2 well (Rhodehamel, 1977). Sand and mud porosity at shallow depths (<500 m) obtained here are higher than was seen at the Cost B-2 well.
The Bass River and Ancora boreholes targeted older sequences of the Upper Cretaceous to Paleocene. This new data allow for more accurate estimate of the magnitude of long-term sea-level …
500>Allosteric Tuning Of Ruthenium 2,2’-Bipyridyl Luminescent Sensor Systems, Daqing Gan
Allosteric Tuning Of Ruthenium 2,2’-Bipyridyl Luminescent Sensor Systems, Daqing Gan
Masters Theses
A series of new ruthenium bipyridyl crown supramolecular sensor systems containing two binding sites were synthesized. The crystal structure and photophysical properties of the developed sensor systems were thoroughly studied using x-ray, nuclear magnetic resonance and photoscopy methods. It turned out that the chelation of transition metal on the remote sites of the bipyridyl crown ligands greatly reduced the reactivity of the crown cavity. It is believed that the chelation of transition metal on the nitrogen atoms forces the bipyridyl function towards coplanarity and restricts the conformational freedom of the crown ring. The conformational rigidity in turn influences the binding …
Photophysical Study Of Linked 1,4,7-Triazacyclonane Cr (Iii) Complexes, Weizhen Tu
Photophysical Study Of Linked 1,4,7-Triazacyclonane Cr (Iii) Complexes, Weizhen Tu
Masters Theses
A series of mono and bimetallic Cr(III) complexes based on the 1,4,7- triazacyclonoane(TACN) were prepared. Complexes of the Cr(TACN)X3 , and Cr2(DTNE)X6 demonstrated marked difference of photophysical properties on the nature of X. In cases where X is more easily oxidized, enhanced extinction coefficient in the 4A2 ➔ 2T, absorption and larger quantum yield of emission at 77K were observed in the dimer complexes. Shorter lifetime and enhanced decay rate were also found in the dimer complexes suggests that there might exists weak coupling behavior between the two Cr(III) metal cents in the …
Reaction Of Caffeic Acid With Amino Acids, Yonggang Wang
Reaction Of Caffeic Acid With Amino Acids, Yonggang Wang
Masters Theses
The reaction of caffeic acid with tryptophan was studied as a model for the reaction of caffeic acid with amino acids in the aquatic environment. Although the autoxidation reaction of caffeic acid in aqueous solution with subsequent dimerization had been previously studied, it was examined as well for comparison purposes. The present studies demonstrate that oxidized caffeic acid would react with tryptophan. The reaction, like the dimerization reaction, was catalyzed by the presence of iron(III) ions at low pH ( <4) and by hydroxide ions at high pH (10). The reaction of caffeic acid with itself yielded six products, four of which were identified by mass spectroscopy as dimers, with the other two being trimers. The reaction of caffeic acid with tryptophan yielded three product peaks. Two of the product peaks had similar retention times to the dimers from the self-reaction of caffeic acid; the third was a new product resulting from the reaction of caffeic acid with the tryptophan.
A mechanism for the reaction of caffeic acid with tryptophan has been proposed. This mechanism was based on the analysis …
4)>Control And Data Acquisition For An Electron Spectrometer System, Stanislav Rumega
Control And Data Acquisition For An Electron Spectrometer System, Stanislav Rumega
Masters Theses
An electron spectrometer system, installed on one of the beam lines in the WMU Van de Graaff accelerator laboratory, consists of two 45o parallel-plate electrostatic analyzers, a decelerating grid, and a channeltron. It allows the energy analysis, angular analysis, and the detection of continuum electrons ejected following the bombardment of a target with accelerated ions or electrons. First, the principles of operation of the spectrometer itself are discussed with emphasis on the energy analysis. Next, the electronics and computer interfacing required for control of the spectrometer functions and for acquisition of data are described. Finally, the control and data …
Photodegradation Of Pcbs In Natural Waters, Adriana R. Nicolaescu
Photodegradation Of Pcbs In Natural Waters, Adriana R. Nicolaescu
Masters Theses
PCBs are widely distributed in the environment and they are biologically refractory and toxic compounds. There is great interest in understanding their fate in the environment, and also for finding safe and effective degradation methods.
This study is concerned with the photodegradation of four PCB congeners: PCB 5, PCB 18, PCB 77, PCB 128 in natural waters. Natural waters contain humic substances which can greatly influence the environmental fate of the PCBs. The different degradation of the four congeners was studied in standardized systems and in humic acid or nitrate solutions, under environmental conditions. DMDE and Methoxyclor (whose environmental half-lifetimes …
Superstring Cosmology: An Investigation Into Low Temperature Effective Gauss-Bonnet Corrections To The Einstein Field Equations In An Inflationary Scenario, David Dressel
Masters Theses
Several problems with the inflationary cosmological model and the force coupling constants are addressed in the context of superstring theory. In order to simplify the field equations slightly, vacuum solutions are attempted. The solutions for several field equations are analyzed in order to obtain an inflationary universe that leads to a nearly static internal space. A solution is found when Gauss-Bonnet terms, as well as the Einstein terms, are used in the field equations, along with an exponential radii function for a ten dimensional product space. The solutions lead to a three-phase universe that might describe our very early universe. …
Characterization Of Cosmic Microwave Background Temperature Fluctuations For Cosmological Topologies Specified By Topological Betti Numbers, Troy Gobble
Masters Theses
The cosmic microwave background explorer, COBE, and the Balloon Observations of Millimetric Extragalactic Radiation and Geophysics, BOOMERanG, have collected data from the universe and detected relic anisotropies indicative of one of the earliest events of the universe, decoupling. Hidden in the correlation between these temperature fluctuations is the signature of the global shape, or topology, of the early universe. It is possible to calculate the temperature fluctuations as due to primeval adiabatic density temperature fluctuations from the Sachs-Wolfe effect, which contains a topological term. Here we investigate some of the spaces and how they affect the microwave background.
A large …
Validation Of The Thermochemical Cycle Used In Computing Absolute Gas Phase Acidities And A Molecular-Orbital Study Of Protonated Ammonia-Water Cluster Ions, Jeremiah Aeschleman
Validation Of The Thermochemical Cycle Used In Computing Absolute Gas Phase Acidities And A Molecular-Orbital Study Of Protonated Ammonia-Water Cluster Ions, Jeremiah Aeschleman
Masters Theses
This work is comprised of two separate computational projects, an evaluation of the validity of an assumption made when computing absolute gas phase acidities with a thermochemical cycle and a molecular-orbital study of protonated ammonia-water clusters ions.
Relative gas phase acidities are measured experimentally and then adjusted using Hess' law to align them with an absolute scale. In the Hess' law calculation it is assumed that the electron affinity of A• and the ionization energy of H• are independent of temperature. To test this assumption, absolute enthalpies were computed for the anion (A-) and the radical (A•) at …
A Time Resolved Laser Spectroscopy Study Of Resonance Energy Transfer Between Tb(Iii) And An Organic Dye: 6-Hydroxy-5-[(2-Methoxy-5-Methyl-4-Sulfophenyl)Azo]-2-Naphthalenesulfonic Acid Disodium Salt, Ronald Wesley Tennis
A Time Resolved Laser Spectroscopy Study Of Resonance Energy Transfer Between Tb(Iii) And An Organic Dye: 6-Hydroxy-5-[(2-Methoxy-5-Methyl-4-Sulfophenyl)Azo]-2-Naphthalenesulfonic Acid Disodium Salt, Ronald Wesley Tennis
Masters Theses
Intermolecular energy transfer is a process of crucial importance to photochemistry and photophysics. Complexed lanthanide ions are well suited as energy transfer donors because they display dependable absorption and luminescence qualities with narrow rare-earthion emission in addition to relatively long excited-state lifetimes.
This project used a pulsed nitrogen laser and high speed digital techniques to study energy transfer dynamics between excited state Tb(acac)3 and an ionic organic dye called Red 40. Luminescence decay profiles of excited terbium atoms in the presence of the quencher were measured in both high and low viscosity solvents. The effects of solvent viscosity and …
Equilibrium And Kinetic Studies Of Isomerization Of (Co)5w[Η1-Pph2ch2p(P-Tol)2] And (Co)5w[Η1-P(P-Tol)2ch2pph2], Deliang Chen
Equilibrium And Kinetic Studies Of Isomerization Of (Co)5w[Η1-Pph2ch2p(P-Tol)2] And (Co)5w[Η1-P(P-Tol)2ch2pph2], Deliang Chen
Masters Theses
Unsymmetrical diphosphine tungsten complexes, (CO)5W[η1-PPh2CH2P(p-tol)2] and (CO)5W[η1-P(p-tol)2CH2PPh2], were prepared from (CO)5W(NH2Ph) and Ph2PCH2P(p-tol)2. Two approaches were successfully used to synthesize Ph2PCH2P(p-tol)2. The first utilized PPh2CH2Cl, prepared from PPh2H, CH2Cl2, and KOH under phase transfer conditions, from which Ph2PCH2P(p-tol)2 was …
Investigations Into The Synthesis And Transformations Of An Epoxy Β-Lactone, John Farrell
Investigations Into The Synthesis And Transformations Of An Epoxy Β-Lactone, John Farrell
Masters Theses
In connection with the continuing interests in the stereoselective rearrangements of β-lactones, an investigation of the synthesis and transformations of the epoxy β-lactone 4-(1,2-epoxypentyl)-3-trimethylsilyloxetan-2-one was undertaken. Two synthetic strategies to the desired epoxy β-lactone were studied. The first route was a two-step reaction sequence involving the aldol reaction of trimethylsilylacetic acid with (2R,3S)-epoxyhexanal, followed by lactonization of the resulting β-hydroxy acid with benzenesulfonyl chloride. Complications in preparing the requisite β-hydroxy acids under typical aldol reaction conditions rendered this route unworkable. The complexity and intractability of the aldol reaction mixtures was attributed to the multiple possibilities of …
Degradation Of Trazine Compounds Via Metallic Iron Under Acidic Conditions, Tracy Dombek
Degradation Of Trazine Compounds Via Metallic Iron Under Acidic Conditions, Tracy Dombek
Masters Theses
The degradation of dissolved dimethoxyatrazine (2-chloro-4,6-dimethoxy-1,3,5-triazine), terbutylazine (2-chloro-4-ethylamino-6-terbutylamino-1,3 ,5-triazine) and deisopropylatrazine (2-amino-4-chloro-6-ethylamino-1,3,5-triazine) via metallic iron was studied as a function of solution pH. Generally, degradation was more rapid the lower the solution pH and higher the compound pKa. For dimethoxyatrazine kSA (kSA= k' (min-1)* V (L) / M (g) I SA(m2/g)) was found to be 1.33 (± 0.07) E-4 min-1 m-2 L at pH 2, 6.1 (± 0.6) E-5 min-1 m-2 L at pH 3 and 4.4 (± 0.6) E-5 min-1 m-2 L at pH 4. For …
Alkyl Nitrates During The Prophet ’98 Summer Intensive, Kristi A. Ostling
Alkyl Nitrates During The Prophet ’98 Summer Intensive, Kristi A. Ostling
Masters Theses
As part of the PROPHET intensive held at the University of Michigan Biological Station in northern Michigan, a gas chromatography system for making fast-turnaround measurements of C1 to C5 alkyl nitrates was developed and deployed from July 19 to August 21, 1998. Every 30 minutes, samples were automatically acquired on a small Tenax trap made from silicosteel column and injected on a GC column by thermal desorption prior to ECD detection. Tests performed to measure breakthrough and on-trap destruction indicated no breakthrough for C3, C4, and C5 nitrates and excellent stability for these compounds on the trap. Chromatographic resolution of …
Calibration, Installation Techniques, And Initial Measurements For Vertical Resistivity Probes Used In Hydrogeologic Investigations, Jeffrey Mark Groncki
Calibration, Installation Techniques, And Initial Measurements For Vertical Resistivity Probes Used In Hydrogeologic Investigations, Jeffrey Mark Groncki
Masters Theses
Vertical Resistivity Probes (VRPs) are being increasingly used in a variety of applications where detailed vertical resistivity information in both the vadose and saturated zones is needed. All the different possible array types and spacings must be calibrated for the effect of the 2" (outer diameter) insulating PVC cylinder on which the electrodes are mounted. Apparent resistivities must be corrected by calibration factors. Varying the installation parameters greatly influences the measured apparent resistivity because of the disturbed annulus and the composition of the backfill materials. Bentonite slurry is necessary for the installations to keep the electrodes in good contact with …
Stratigraphic Analysis Of Diamicton Units In North-Central St. Joseph County, Michigan, Andrew C. Flint
Stratigraphic Analysis Of Diamicton Units In North-Central St. Joseph County, Michigan, Andrew C. Flint
Masters Theses
Seven subsurface glacial diamicton units, including a paleosol, have been characterized from two borings in north-central St. Joseph County, Michigan. These units have been characterized in terms of their clay mineralogy, texture, color, and stratigraphic position. t-Tests confirm that each unit displays a significant difference in mean 7A/10A peak height ratio from all other units.
Unit 4, informally called the Gray Marker tilt has been correlated between borings in this study and to the findings of others (Gardner, 1997, Nicks, in preparation). The Newbury till described by the Indiana Geological Survey (unpublished data) may also correlate to Unit 4, raising …
Multiple Isotopic Studies Of Calcium Carbonate Growths In Concrete Structures, Danielle M. Schmitt
Multiple Isotopic Studies Of Calcium Carbonate Growths In Concrete Structures, Danielle M. Schmitt
Masters Theses
Secondary minerals, predominantly carbonates, forming under concrete structures have received attention in terms of their possible role in the degradation of their hosts. δ13C and δ18O analyses of several calcium carbonate growths collected from bridges in Michigan and New York were performed. The δ13C and δ18O values clustered around -24.7 ± 1(PDB) and 13.7 ± 1(SMOW) ‰, respectively. A positive δ18O- δ13C correlation suggests kinetically driven precipitation involving atmospheric CO2• 14C activities determined for select samples support the theory that atmospheric CO2 is involved …
Spectroscopic And Kinetic Investigation Of Carbocation Reactivity In Supercritical Carbon Dioxide, Hongshu Jin
Spectroscopic And Kinetic Investigation Of Carbocation Reactivity In Supercritical Carbon Dioxide, Hongshu Jin
Masters Theses
Recent interest in the use of supercritical CO2 as an environmentally benign reaction medium has included the development of solvent systems that may support polar and ionic chemistry. Carbocations are key intermediate in a variety of synthetically important reactions and characterization of their reactivity is the focus of this work. UV-visible absorption, and steady-state and time-resolved fluorescence spectroscopy has been used to identify and monitor the reaction kinetics of 9- phenylxanthenium carbocation. The arylcarbocation is conveniently generated from 9- phenylxanthen-9-ol in supercritical CO2 under mildly acidic conditions. Under these conditions 9-phenylxanthenium ion is extremely stable and persists for …
Efficiency Of Distributed Priority Queues In Parallel Adaptive Integration, Rodger Zanny
Efficiency Of Distributed Priority Queues In Parallel Adaptive Integration, Rodger Zanny
Masters Theses
The adaptive integration algorithm is· effective in numerically solving integration problems. It is able to focus the application of integration rules on the portion of the integration region where the integrand is the least well-behaved. Parallel implementations must use dynamic load balancing or performance suffers.
Dynamic local load-balancing techniques allow each processor to maintain its own pool of work in a local priority queue and balance the workload based on local criteria. However, the use of locally controlled priority queues is known to be inefficient (in terms of the number of integration rule applications needed to reach an answer) as …
Gas Sparging And Humic Acid Sorption/Desorption, Masaki Sakakibara
Gas Sparging And Humic Acid Sorption/Desorption, Masaki Sakakibara
Masters Theses
Partition coefficients (KDOC) for sorption of PAHs and chlorinated benzenes to dissolved humic acids (HA) were measured using gas-sparging methodology. The resulting KDOC values were significantly lower than the KOW-based KDOC values, which generally appear to provide reliable estimates for KDOC values. The KDOC values measured by gas sparging were also strongly influenced by the concentration of HA in solution, as measured by dissolved organic carbon content (DOC). Increasing DOC concentration consistently resulted in decreased KDOC values for all compounds investigated. Previous studies have claimed that KDOC values measured using …
Investigating The Allosteric Behavior Of Malate Dehydrogenase From Escherichia Coli, Eman M. Ghanem
Investigating The Allosteric Behavior Of Malate Dehydrogenase From Escherichia Coli, Eman M. Ghanem
Masters Theses
Regulatory mechanisms of malate dehydrogenase from E.coli (eMDH) involving NADH as an allosteric effector were investigated. The reaction was studied in both directions: malate oxidation and oxaloacetate reduction. When malate was the variable substrate, a plot of rate against substrate concentration was sigmoidal in the presence of 0.065 mM NADH, which indicates the presence of an allosteric site for NADH on the enzyme. Binding of NADH at the allosteric site causes conformational changes in the active site and, thereby, changes the catalytic activity of the enzyme. An increase in Km value, from 1.3 to 3.9 mM malate was observed, …
Optimization Of The Reaction Of Hexamethyldisilazane On A Fumed Silica Surface, Frederick R. Jones
Optimization Of The Reaction Of Hexamethyldisilazane On A Fumed Silica Surface, Frederick R. Jones
Masters Theses
Hexamethyldisilazane (HMDS) is commonly used to transfer trimethylsilyl (TMS) groups to silica surfaces. While studies have been done examining individual factors that influence the reaction, no investigations have reported how these factors affect each other. The factors examined in this study include temperature, presence of catalyst (butylamine), pretreatment, time, concentration, solvent, and presence of water in the solvent. The purpose of this study is to examine potential factors and two-way interactions to determine which significantly affect the yield and produce an optimum set of conditions.
The HMDS reactions occurred in an organic solvent slurry under nitrogen. Using statistical experimental design, …
Investigations Of A Phenanthroline-Based Azo Dye Ligand And Of Re(I) And Ru(Ii) Complexes Based On This Ligand, Yan Zhang
Masters Theses
A 1,10-phenanthroline based azo dye ligand, phen-azo-phenol, produced by diazotizing 5-amino-1,10-phenanthroline (5-NH2-phen) and then coupling to phenol, and several transition metal complexes containing this ligand, have been synthesized and characterized. The phen-azo-phenol ligands attach to Re(I) and Ru(II) through the phenanthroline linkage to form stable polypyridyl complexes. These complexes show greatly enhanced absorption properties in the visible region when compared to the well-known analogous bipyridine and phenanthroline containing complexes. The visible light absorption of the free ligand and the complexes containing this ligand are greatly affected by the position of the deprotonation equilibrium of the -OH group on …
A Portable, Object-Oriented Library For Neural Network Simulation, Martin P. Franz
A Portable, Object-Oriented Library For Neural Network Simulation, Martin P. Franz
Masters Theses
A portable, object-oriented library for simulation of general Multi-layer Feedforward Neural Networks (MLFNs) is described. Unlike all-encompassing neural network simulation environments, the library was designed to allow convenient use in existing programs and in applications where training and testing data are generated using separate, often complex simulations.
The library' s design goals include modularity, portability, efficiency, correctness, compactness, and type-safety. To demonstrate how these objectives are met, competing architectural choices are presented, along with the criteria used for determining the strategy actually implemented. Sample applications using the library are presented, showing how the library' s class files are used in …
Nickel Subsulfide Can Protect Human Fibroblasts From The Mutagenic Effect Of Benzo[A]Pyrene Diolepoxide, Samir M. Hamdan
Nickel Subsulfide Can Protect Human Fibroblasts From The Mutagenic Effect Of Benzo[A]Pyrene Diolepoxide, Samir M. Hamdan
Masters Theses
Cancer researchers are interested in identifying the environmental causes and synergistic influences of different carcinogens. It is important to examine the combined effect of multiple carcinogens since this is a more realistic representation of the true environmental situation in which we are exposed daily. Our study has reported that pretreating human fibroblasts with nickel subsulfide followed by the simultaneous treatment with both nickel subsulfide and benzo[a]pyrene diolepoxide (BPDE) can protect human fibroblasts from the mutagenic effects of BPDE. These results correlate well with our previous chromium-BPDE co-treatment work, suggesting a transition metal dependent protective effect. This protective effect was dependent …
Application Of The Paleomagnetic Fold Test To Determine The Relative Timing Of Sill Intrusion And Deformation In The Southwest Helena Salient, Montana, Stephen Christopher Whisner
Application Of The Paleomagnetic Fold Test To Determine The Relative Timing Of Sill Intrusion And Deformation In The Southwest Helena Salient, Montana, Stephen Christopher Whisner
Masters Theses
The Doherty Mountain fold complex is a highly folded and faulted region along the southern boundary of the Helena Salient in southwestern Montana. This region has a complex deformation history that is a key to deformation within the Helena Salient as a whole. A structural interpretation of the deformed rocks of this area was conducted using field mapping and cross section construction at 1:24,000 scale providing insight to the internal deformation processes involved. Fourteen folds and three major faults were mapped and analyzed showing the influence of the Southwest Montana Transverse Zone and late stage detachment faulting on fold orientation. …
Separation And Determination Of Monochlorophenols By Capillary Zones Electrophoresis, Zarina Yasmin Banu
Separation And Determination Of Monochlorophenols By Capillary Zones Electrophoresis, Zarina Yasmin Banu
Masters Theses
Chlorine has been widely used in industry. One of the most common uses of chlorine is in municipal water treatment plants. Chlorine reacts with a variety of organic compounds, among these are phenol and its derivatives which are commonly found in natural waters. When these compounds react with chlorine, a variety of chlorine substituted and oxidized products result depending on concentrations, pH, and temperature. In order to study these reactions it is necessary to separate and determine the various products produced.
Earlier studies have shown 3-chloro and 4-chlorophenol cannot be separated by commercial GLC columns. GC/MS (electron impact) measurements cannot …
Synthesis, Characterization And Photophysical Behavior Of A Cr(Iii) Bimetallic System, Yan Chen
Synthesis, Characterization And Photophysical Behavior Of A Cr(Iii) Bimetallic System, Yan Chen
Masters Theses
Many binuclear transition metal complexes have been studied to understand the nature of interactions between the metal centers. People have found Simultaneous Pair Excitation phenomenon in some bimetallic system that can serve as a potential source of Non-Linear Optical behavior.
Thus a series of Cr2 -([14]aneN4)2-X4n+ complexes were synthesized and characterized. Only the cis,cis configuration was found. The results were compared with those of their monomer analogs. The electronic structures are very similar in both monomer and dimer complexes. The quantum yield, UV-Vis absorption and lifetime studies suggested a possible coupling between the …
Improvement Of Epa Method 8330: Complete Separation Of Explosives Using A Two Phase Approach, Michael J. Lang
Improvement Of Epa Method 8330: Complete Separation Of Explosives Using A Two Phase Approach, Michael J. Lang
Masters Theses
A wide range of primary and secondary contaminants is found in environmental matrices containing explosive residues. HPLC methodology for the detection of explosive is now standardized in EPA Method 8330, and represents the most common method currently used for explosive analysis. However, co-elution of some of the analytes occurs even using method 8330. As a result, explosive analysis using HPLC have required the use of a confirmation column in an additional analysis step.
In the current work, all of the compounds in the EPA 8330 explosives list were resolved using a single HPLC separation. While the EPA 8330 HPLC conditions …