Edward Navarre

Associate Professor

Department of Chemistry

Southern Illinois University Edwardsville

Dr. Edward Navarre
Department of Chemistry, Box 1652
Southern Illinois University Edwardsville
Edwardsville, IL 62026

email

tel. 618.650.2076
fax. 618.650.3556

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    AuthorTitleYearJournal/ProceedingsReftypeDOI/URL
    Galia, A., Navarre, E., Scialdone, O., Ferreira, M., Filardo, G., Tilloy, S. & Monflier, E. Complexation of phosphine ligands with peracetylated β-cyclodextrin in supercritical carbon dioxide: Spectroscopic determination of equilibrium constants 2007 Journal of Physical Chemistry B
    Vol. 111(10), pp. 2573-2578 
    article DOI URL 
    Abstract: The interaction between peracetylated β-cyclodextrin and several triphenyl phosphine derivatives was studied in supercritical carbon dioxide (scCO2) by UV-visible spectroscopy. The equilibrium constant for a 1:1 complexation reaction was obtained from titration spectra and calculated using two established mathematical models. The values of the equilibrium constants are 1-3 orders of magnitude smaller than those obtained in aqueous solution with analogous phosphines. This is likely due to the absence in scCO2 of the hydrophobic effect, which is replaced by a corresponding, but weaker, CO2-phobic effect. The largest value of Kf was found for complexes of diphenyl(4-adamantylphenyl)phosphine, which is rationalized on the basis of the excellent fit of the phosphine in the cyclodextrin cavity, leading to enhanced host-guest van der Waals interactions. This study can be considered the first step toward the comprehension of the complexation thermodynamics of modified cyclodextrins soluble in scCO2.
    BibTeX:
    @article{Galia2007,
      author = {Galia, A. and Navarre, E.C. and Scialdone, O. and Ferreira, M. and Filardo, G. and Tilloy, S. and Monflier, E.},
      title = {Complexation of phosphine ligands with peracetylated β-cyclodextrin in supercritical carbon dioxide: Spectroscopic determination of equilibrium constants},
      journal = {Journal of Physical Chemistry B},
      year = {2007},
      volume = {111},
      number = {10},
      pages = {2573--2578},
      url = {http://pubs.acs.org/doi/abs/10.1021/jp0673112},
      doi = {http://dx.doi.org/10.1021/jp0673112}
    }
    
    Galia, A., Navarre, E.C., Scialdone, O., Filardo, G. & Monflier, E. Complexation of phosphine ligands with peracetylated-[beta]-cyclodextrin in supercritical carbon dioxide: Effect of temperature and cosolvent on the equilibrium constant 2009 The Journal of Supercritical Fluids
    Vol. 49, pp. 154-160 
    article DOI URL 
    Abstract: The interaction between peracetylated-[beta]-cyclodextrin and tert-butyl and adamantyl functionalized triphenylphosphine derivatives was studied in supercritical carbon dioxide (scCO2) based solvent media by UV-vis spectroscopy. The equilibrium constant for a 1:1 complexation reaction was obtained from titration spectra both in pure carbon dioxide and in the presence of methanol as a cosolvent in the temperature range 308-323 K to estimate the internal energy and entropy of the inclusion equilibrium. The values of the equilibrium constants were found significantly smaller than those obtained in aqueous solution with analogous phosphines and substantially independent of the nature of the phosphine and of the solvent medium. On the basis of the results that we have obtained in this study we do believe that a possible explanation of the unfavorable complexation equilibria in CO2 based solvent systems could be a distorsion of the conformation of the cyclic oligosaccharides arising from the vanishing of the hydrogen bond interactions between contiguous glucose units of the peracetylated cyclodextrin.
    BibTeX:
    @article{Galia2009,
      author = {Galia, Alessandro and Navarre, Edward C. and Scialdone, Onofrio and Filardo, Giuseppe and Monflier, Eric},
      title = {Complexation of phosphine ligands with peracetylated-[beta]-cyclodextrin in supercritical carbon dioxide: Effect of temperature and cosolvent on the equilibrium constant},
      journal = {The Journal of Supercritical Fluids},
      year = {2009},
      volume = {49},
      pages = {154--160},
      url = {http://www.science-direct.com/science/article/B6VMF-4VNK69J-1/2/876a65c9ec887531f047107b267d45e6},
      doi = {http://dx.doi.org/10.1016/j.supflu.2009.02.002}
    }
    
    Galia, A., Navarre, E.C., Scialdone, O., Filardo, G. & Monflier, E. Supramolecular chemistry of Cyclodextrins in supercritical carbon dioxide: Spectroscopic Investigations 2007 5th International Symposium on High Pressure Processes Technology and Chemical Engineering, June 2007, Segovia, Spain  conference  
    Abstract: Considering the high solubility of peracetylated-β-cyclodextrin (perAc-β-CD) in supercritical carbon dioxide (scCO2), it presents a means to increase the solubility of organometallic catalysts via the formation of inclusion complexes. The supramolecular chemistry of perAc-β-CD as a host for triphenyphosphine derivatives has been studied in scCO2 using UV absorption spectroscopy. It was found that the inclusion constant at 40 °C and 30 MPa is 10 to 1000 times smaller compared to analogous systems in aqueous solvent. Methanol is added to the scCO2 as a cosolvent to exploit the tunability of the supercritical phase and access a range of solvent polarities by varying the temperature, pressure, and fraction of methanol. This study is pursued with the goal of reaching a better comphension of the main factors affecting the phosphine–perAc-β-CD complexation to define rationale criteria for the design of phosphine ligands with high complexation constants suitable as supramolecular ligands for homogeneous catalysis in scCO2.
    BibTeX:
    @conference{Galia2007a,
      author = {Alessandro Galia and Navarre, Edward C. and Onofrio Scialdone and Giuseppe Filardo and Eric Monflier},
      title = {Supramolecular chemistry of Cyclodextrins in supercritical carbon dioxide: Spectroscopic Investigations},
      booktitle = {5th International Symposium on High Pressure Processes Technology and Chemical Engineering, June 2007, Segovia, Spain},
      year = {2007}
    }
    
    Goldberg, J., Many, K., Pierz, E. & Navarre, E. Development and Evaluation of Direct Solid Sampling Methodologies for Plasma Gun-ICP AES 1998 FACSS Conference; Austin, TX, U.S.A.  conference  
    Abstract: Our approach towards the direct elemental analysis of solid materials has involved the development of a high-energy pulsed plasma device (a plasma gun) for solid sampling. Material sampled by the plasma gun (PG) is then transported into a conventional ICP for re-excitation and atomic emission measurements. We will describe this tandem plasma source (PG-ICP) and discuss the parameters controlling sample atomization, transport, and excitation. We have applied this source towards the analysis of refractory solid materials and will present results of determinations of various elements in NIST SRM's (e.g., silica brick, brick clay, river sediment) as well as other refractory materials (USGS reference rocks, zeolites, ca.). Calibration involves the use of only pure elemental standards (no matrix matching) for powder samples delivered from an alcoholic slurry into the plasma gun. The potential for analyses of bulk solids will be discussed and initial results presented.
    BibTeX:
    @conference{Goldberg1998,
      author = {Joel Goldberg and Kerri Many and Elizabeth Pierz and Edward Navarre},
      title = {Development and Evaluation of Direct Solid Sampling Methodologies for Plasma Gun-ICP AES},
      booktitle = {FACSS Conference; Austin, TX, U.S.A.},
      year = {1998}
    }
    
    Goldberg, J., McKinstry, J., Minnick, W. & Navarre, E. Direct Solid Sampling Via Plasma Gun-ICP-AES 1997 FACSS Conference; Providence, RI, U.S.A.  conference  
    Abstract: The plasma gun atomization cell developed in our laboratory has demonstrated the ability to sample even the most refractory solid materials as efficiently as it samples aqueous solution residues. This has allowed us to use pure elemental standards for direct elemental quantification in solid powder samples using a tandem plasma gun/ICP (PG-ICP) emission system. We have also developed external sampling methods with allow the plasma gun to be used for the analysis of bulk solid materials. PG-ICP analysis results for NIST SRMs and USGS Reference Rocks will be presented as well as initial results of bulk sampling plasma gun studies. Lastly, the potential of a new high-frequency plasma gun device will be discussed with respect to its solid sampling properties.
    BibTeX:
    @conference{Goldberg1997,
      author = {Joel Goldberg and James McKinstry and Whitney Minnick and Ed Navarre},
      title = {Direct Solid Sampling Via Plasma Gun-ICP-AES},
      booktitle = {FACSS Conference; Providence, RI, U.S.A.},
      year = {1997}
    }
    
    Goldberg, J. & Navarre, E. Taming the Electrodeless Imploding Thin Film Plasma: A Tribute to the Spectroscopic Inspiration of Richard Sacks 2007 Anachem/SAS Symposium, Livonia, Michigan, November 1, 2007  conference  
    BibTeX:
    @conference{Goldberg2007,
      author = {Goldberg, Joel and Navarre, Edward},
      title = {Taming the Electrodeless Imploding Thin Film Plasma: A Tribute to the Spectroscopic Inspiration of Richard Sacks},
      booktitle = {Anachem/SAS Symposium, Livonia, Michigan, November 1, 2007},
      year = {2007}
    }
    
    Goldberg, J. & Navarre, E. Design and Modeling Studies of a MicroThetaPinch Plasma Source for Atomic Emission Spectrometry 2003 FACSS Conference; Fort Lauderdale, FL, U.S.A.  conference  
    Abstract: Previously, we have demonstrated the ability to create pulsed plasmas via coupling energy from a high-frequency high-voltage capacitive electrical discharge through a coil surrounding a cylindrical aluminum thin film. This so-called Theta-Pinch Plasma Gun was able to atomize solid samples deposited on the thin film and generate emission spectra suitable for AES.

    Here we will present results of electrical and magnetic field modeling studies exploring the possibility of miniaturizing this plasma source. The advantages of miniaturization include decreased electrical discharge requirements, enhanced coupling due to higher-frequency discharges, and higher magnetic fields due to decreased coil diameter. The role of the conductive metallic film will be explored and alternative coupling mechanisms investigated.

    BibTeX:
    @conference{Goldberg2003,
      author = {Joel Goldberg and Edward Navarre},
      title = {Design and Modeling Studies of a MicroThetaPinch Plasma Source for Atomic Emission Spectrometry},
      booktitle = {FACSS Conference; Fort Lauderdale, FL, U.S.A.},
      year = {2003}
    }
    
    Goldberg, J. & Navarre, E. The Theta-pinch Plasma gun: sampling strategies for direct solid sampling AES 2001 FACSS Conference; Detroit MI, U.S.A.  conference  
    Abstract: A pulsed plasma can be generated via discharge of a high-voltage capacitor bank through a specially-designed coil surrounding a thin conductive metallic film. In this manner, a high-temperature plasma can be generated (without electrodes) at atmospheric pressure which may be useful for the direct atomization of solid samples for analysis via ICP-AES. The effect of electrical discharge properties (such as discharge frequency and magnetic field strength) as well as thin film properties and fill gas identity have been investigated and will be evaluated relative to plasma initiation and plasma heating. Using conditions with which these processes are optimized, the utility of the device as a direct solid sampling source for AES wll be evaluated and presented. The results of spatially and temporally resolved emission studies will be presented and used to establish a model describing plasma formation, heating, and solid sample atomization mechanisms.
    BibTeX:
    @conference{Goldberg2001,
      author = {Joel Goldberg and Ed Navarre},
      title = {The Theta-pinch Plasma gun: sampling strategies for direct solid sampling AES},
      booktitle = {FACSS Conference; Detroit MI, U.S.A.},
      year = {2001}
    }
    
    Goldberg, J. & Navarre, E. High-Frequency Plasma Guns: Z-Pinch and Theta-Pinch Plasmas for Direct Solid Sampling AES 1998 FACSS Conference; Austin, TX, U.S.A.  conference  
    Abstract: We report here on the results of studies of plasma generation systems suitable for the creation of both z-pinch plasma gun discharges (axial current flow; electrodes) and theta-pinch plasma gun discharges (radial current flow; electrodeless). Two coils have been investigated for the production of a theta-pinch plasma gun and the results of studies utilizing aluminum foils and thin films for plasma generation will be presented. The results of electrical characterization studies of these discharges will be presented and discussed relative to plasma production efficiency. Prospect of using these discharges as direct solid sampling devices suitable for coupling with an ICP for AES detection.
    BibTeX:
    @conference{Goldberg1998a,
      author = {Joel Goldberg and Edward Navarre},
      title = {High-Frequency Plasma Guns: Z-Pinch and Theta-Pinch Plasmas for Direct Solid Sampling AES},
      booktitle = {FACSS Conference; Austin, TX, U.S.A.},
      year = {1998}
    }
    
    Goldberg, J., Navarre, E. & Many, K. Direct Solid Sampling Methods Using a Plasma Gun Device For Sample Introduction Into an ICP 1999 FACSS Conference; Vancouver, B.C., Canada  conference  
    Abstract: A pulsed plasma device suitable for the direct analysis of solid materials has been developed and studied in our laboratory for a number of years. We have successfully coupled this plasma gun device with an ICP and have demonstrated the use of pure calibration standards for matrix-independent elemental analysis of refractory solids. Here we report on two advances in the development of methods and new instrumentation for these analyses. First, studies investigating the utility of using the plasma gun for external sampling will be presented and compared with earlier work involving sample deposition inside the discharge tube. External sampling methods should improve the sampling efficiency and permit the analysis of bulk solid materials (in addition to powdered materials). Next, initial studies of solid sampling processes in an electrodeless plasma gun device will be presented.
    BibTeX:
    @conference{Goldberg1999,
      author = {Joel Goldberg and Edward Navarre and Kerri Many},
      title = {Direct Solid Sampling Methods Using a Plasma Gun Device For Sample Introduction Into an ICP},
      booktitle = {FACSS Conference; Vancouver, B.C., Canada},
      year = {1999}
    }
    
    Goldberg, J., Navarre, E. & Minnick, W.J. High-Frequency Plasma Gun Discharges and the Development of a Theta-Pinch Plasma Gun for Atomic Emission Spectroscopy 1997 FACSS Conference; Providence, RI., U.S.A.  conference  
    Abstract: While the plasma gun discharge source developed in our lab has demonstrated its utility as a direct solids analysis tool for atomic emission spectrometric measurements, much of the discharge energy (as well as subsequent re-excitation source energy) is wasted on the vaporization of the graphite electrodes used in the creation of the plasma. We report here on our initial studies of systems suitable for the electrodeless production of plasma gun discharges (theta-pinch plasma gun). Since theta-pinch capacitive discharges must be at a considerably higher frequency than those typically used to date in our lab, the emission and electrical properties of conventional (i.e., with electrodes) plasma gun discharges generated with these high-frequency discharge systems have been studied. The plasma expulsion and propagation properties of these high-frequency plasma gun systems will be described and our initial results with systems developed for the electrodeless (theta-pinch) plasma gun discharges presented.
    BibTeX:
    @conference{Goldberg1997a,
      author = {Joel Goldberg and Ed Navarre and Minnick, Whitney J.},
      title = {High-Frequency Plasma Gun Discharges and the Development of a Theta-Pinch Plasma Gun for Atomic Emission Spectroscopy},
      booktitle = {FACSS Conference; Providence, RI., U.S.A.},
      year = {1997}
    }
    
    Navarre, E. & Goldberg, J. Spectroscopic Studies of Emission from an Electrodeless Plasma Gun Direct Solid Sampling Source 1999 FACSS Conference; Vancouver, BC., Canada  conference  
    Abstract: A pulsed plasma can be generated via discharge of a high-voltage capacitor bank through a specially-designed coil surrounding a thin conductive metallic film. In this manner, a high-temperature plasma can be generated at atmospheric pressure which may be useful for the direct atomization of solid samples for analysis via ICP-AES spectrometry. In this presentation, the results of temporally and spatially resolved spectroscopic measurements of emission from this electrodeless plasma gun device will be presented and evaluated with respect to the mechanism of plasma formation. Special attention will be given to the effects of magnetic field strength versus induced current relative to plasma compression and plasma formation, respectively. The potential of this device as a direct solid sampling method for use with ICP excitation or ionization will be discussed.
    BibTeX:
    @conference{Navarre1999,
      author = {Edward Navarre and Joel Goldberg},
      title = {Spectroscopic Studies of Emission from an Electrodeless Plasma Gun Direct Solid Sampling Source},
      booktitle = {FACSS Conference; Vancouver, BC., Canada},
      year = {1999}
    }
    
    Navarre, E., Goldberg, J. & Gluodenis, R. Modeling, Design and Characterization of Capacitive Discharge Systems for the Production of Pulsed Magnetic Fields Suitable for the Magnetic Modification of Plasmas for Atomic Emission Spectroscopy 1997 FACSS Conference; Providence, RI., U.S.A.  conference  
    Abstract: The development of capacitive discharge instrumentation for studying the effects of pulsed magnetic fields on analytical plasmas requires careful matching of the electrical properties of both the discharge source as well as the load coil used to expose the plasma to the magnetic field. In this poster, we will present the methods used in our lab for designing, modelling and characterizing these magnetic field discharge systems, with special emphasis on magnetic field/laser plasma interactions and the development of a theta-pinch plasma gun source. Specifically, our magnetic field production/theta-pinch modelling program has been re-written as a macro program (running within Excel). Experimental results from new coils designed with this program will be presented and compared with the results predicted by the modeling macro.
    BibTeX:
    @conference{Navarre1997,
      author = {Ed Navarre and Joel Goldberg and Robert Gluodenis},
      title = {Modeling, Design and Characterization of Capacitive Discharge Systems for the Production of Pulsed Magnetic Fields Suitable for the Magnetic Modification of Plasmas for Atomic Emission Spectroscopy},
      booktitle = {FACSS Conference; Providence, RI., U.S.A.},
      year = {1997}
    }
    
    Navarre, E.C., Galia, A., Scialdone, O., Filardo, G. & Monflier, E. Inclusion complexes of triphenylphosphine derivatives and peracetylated-?-cyclodextrin in supercritical carbon dioxide 2008 Journal of Physics: Conference Series
    Vol. 121(2), pp. 022022 
    article DOI URL 
    Abstract: The supramolecular chemistry of peracetylated-β-CD (perAc-β-CD) as a host for triphenyphosphine derivatives has been studied in supercritical (scCO2 ) using UV absorption spectroscopy. It was found that the association constant in scCO 2 at 40°C and 300 bar is 10 to 1000 times smaller compared to analogous systems in aqueous solvent. Studies of the thermodynamics of the inclusion process found an enthalpy of association of -30 kJ/mole and an entropy of -55 J/moleK. This difference with respect to water is attributed to the absence of the hydrophobic effect in scCO 2 due to the much smaller polarity of scCO 2 versus water. To further explore the effect of the solvent on the association constant, values of solvent polarity intermediate between the limits of scCO 2 and water could be useful. To this end, methanol is added to the scCO 2 as a cosolvent to modify the overall polarity. By taking advantage of the tunability of the supercritical phase, a wide range of solvent polarity can be accessed by varying the temperature (35 to 50°C), pressure (200 to 400 bar), and mole fraction of methanol. This study is pursued to obtain a better comprehension of the inclusion process in CO 2 -based supercritical fluids to make the association constant of the phosphine-perAc-β-CD system comparable to those observed in aqueous systems.
    BibTeX:
    @article{Navarre2008,
      author = {Navarre, Edward C. and Galia, Alessandro and Scialdone, Onofrio and Filardo, Giuseppe and Monflier, Eric},
      title = {Inclusion complexes of triphenylphosphine derivatives and peracetylated-?-cyclodextrin in supercritical carbon dioxide},
      journal = {Journal of Physics: Conference Series},
      year = {2008},
      volume = {121},
      number = {2},
      pages = {022022},
      url = {http://iopscience.iop.org/1742-6596/121/2/022022},
      doi = {http://dx.doi.org/10.1088/1742-6596/121/2/022022}
    }
    
    Navarre, E.C., Galia, A., Scialdone, O., Filardo, G. & Monflier, E. Inclusion complexes of triphenylphosphine derivatives and peracetylated-β-cyclodextrin in supercritical carbon dioxide 2007 Joint 21st AIRAPT and 45th EHPRG International Conference on High Pressure Science and Technology, September 17-21, 2007, Catania, Italy  conference  
    Abstract: Viewed as an alternative solvent system for industrial chemical syntheses, supercritical carbon dioxide (scCO2) presents many opportunities and challenges in its application. The insufficient solubility of common organometallic catalysts impedes the use of scCO2 for many reactions employing homogeneous catalysis. In practice, limited solubility is a common problem for a wide range of solutes in scCO2 and is often resolved by modifying the compound to make it more CO2-philic. We have demonstrated an enhanced solubility of triarylphosphines in scCO2 using a host-guest interaction between the phosphine and peracetylated-β-cyclodextrin (perAc-β-CD) [G. Filardo, M. Di Blasi, A. Galia, A. Ponchel; H. Bricout, A. D. Sayede, E. Monflier, J. Supercrit. Fluids, 173 (2006)]. Considering the high solubility of perAc-β-CD in scCO2, it presents a means to increase the solubility of organometallic catalysts without changing the structure of the catalyst and potentially altering its activity. For this approach to be practical, the inclusion constant (K) should be large, for example in similar aqueous systems K is often 103 to 105. In this work, the supramolecular chemistry of perAc-β-CD as a host for triphenyphosphine derivatives has been studied in scCO2 using UV absorption spectroscopy. It was found that the inclusion constant in scCO2 at 40 °C and 300 bar is 10 to 1000 times smaller compared to analogous systems in aqueous solvent. This striking difference is attributed to the absence of the hydrophobic effect in scCO2 due to the much smaller polarity of scCO2 versus water. To further explore the effect of the solvent on the inclusion constant, values of solvent polarity intermediate between the limits of scCO2 and water are needed. To this end, methanol is added to the scCO2 as a cosolvent to modify the overall polarity. By taking advantage of the tunability of the supercritical phase, a wide range of solvent polarity can be accessed by varying the temperature (35 to 50 °C), pressure (100 to 400 bar), and mole fraction of methanol. This study is pursued with the goal of enhancing the phosphine–perAc-β-CD inclusion constant to make it comparable to those observed in aqueous systems.
    BibTeX:
    @conference{Navarre2007,
      author = {Navarre, Edward C. and Galia, Alessandro and Scialdone, Onofrio and Filardo, Giuseppe and Monflier, Eric},
      title = {Inclusion complexes of triphenylphosphine derivatives and peracetylated-β-cyclodextrin in supercritical carbon dioxide},
      booktitle = {Joint 21st AIRAPT and 45th EHPRG International Conference on High Pressure Science and Technology, September 17-21, 2007, Catania, Italy},
      year = {2007}
    }
    
    Navarre, E.C., Galia, A., Scialdone, O., Filardo, G. & Monflier, E. Chimica Supramolecolare della β-Ciclodestrina nell’Anidride Carbonica Supercritica: Studi Spettroscopici 2007 Convengo della Società Chimica Italiana Sezione Calabria e Sicilia; Palermo  conference  
    Abstract: Nonostante le sue utili proprietà chimico-fisiche, l’applicazione dell’anidride carbonica supercritica (scCO2) come solvente è spesso limitata dalla poca solubilità per i substrati polari ed i catalizzatori. La soluzione a questi problemi di solubilità in laboratorio è di utilizzare tensioattivi fluorinati o di apportare modifiche tramite l’aggiunta di leganti perfluorinati, misure sia costose che difficili da applicare se trasposte in scala industriale. Il lavoro che presentiamo propone l’uso della β-ciclodestrina come ospite supramolecolare, modificata per migliorare la solubilità dei substrati e dei catalizzatori nel scCO2. A questo fine è stata studiata l’azione tra la β-ciclodestrina peracetilata e una serie di derivate della trifenil fosfina tramite analisi spettroscopica dell’ultravioletto. La costante di equilibrio (Kf) per una reazione di complessazione a concentrazione 1:1 è stata ottenuta da titolazioni spettroscopiche e calcolata tramite due modelli matematici già noti. I valori delle costanti di equilibrio a 40 °C e 30 MPa sono dell’ordine di 100-500, e cioè da uno a tre ordini di grandezza inferiori a quelli ottenuti in soluzione acquose con le stesse fosfine. Probabilmente questo è dato dalla mancanza dell’effetto idrofobico nel scCO2 che in questo caso è stato sostituito da un effetto di CO2-fobia più debole ma corrispondente. Questi risultati preliminari dimostrano più specificamente che Kf è dipendente dal tipo di fosfina usato e quindi fornisce le basi per progettare un’arilfosfina con più solubilità nel scCO2. In senso più generale, questo lavoro mostra l’importanza di considerare la polarità, l’idrofobicità e la grandezza del soluto se si vuole ottenere inclusione e trasporto in questo solvente insolito. Questo lavoro quindi può essere considerato il primo passo verso l’interpretazione delle proprietà termodinamiche di complessazione delle ciclodestrine modificate nel scCO2
    BibTeX:
    @conference{Navarre2007a,
      author = {Navarre, Edward C. and Alessandro Galia and Onofrio Scialdone and Giuseppe Filardo and Eric Monflier},
      title = {Chimica Supramolecolare della β-Ciclodestrina nell’Anidride Carbonica Supercritica: Studi Spettroscopici},
      booktitle = {Convengo della Società Chimica Italiana Sezione Calabria e Sicilia; Palermo},
      year = {2007}
    }
    
    Navarre, E. and Goldberg, J. Design and characterization of a theta-pinch imploding thin film plasma source for atomic emission spectrochemical analysis 2011 Applied Spectroscopy
    Vol. 65(1), pp. 26-35 
    article DOI URL 
    Abstract: A new atomization device for direct atomic spectrochemical analysis has been developed that uses the theta-pinch configuration to generate a pulsed, high-energy-density plasma at atmospheric pressure. Energy from a 20-kV, 6.05-μF capacitive electrical discharge was inductively coupled to a sacrificial aluminum thin film to produce a cylindrical plasma. Current waveform analysis indicates an average power dissipation of 0.5 MW in the plasma. Electromagnetic modeling studies were used to identify thetapinch designs possessing characteristics favorable to both plasma initiation and plasma heating. The discharge was most robust when the induced current and rate of magnetic field change were maximized. Minimizing the ratio of the coil's width to its radius was also critical. Counter to intuition, a larger diameter was found to be more successful. Spectroscopic studies indicate that the discharge forms a heterogeneous plasma with a dense, cylindrical plasma sheet confined by the walls of the discharge tube surrounding a less energetic plasma in the center. Al(II) emission in the outer plasma cylinder was temporally aligned with the induced current whereas in the center it aligns with the magnetic field. Ionization of support gas species (Ar, He, and air) was not observed, although the identity of the gas had a significant influence on the plasma reproducibility. The optimized design utilized a 5.5-turn, 19-mm-diameter theta coil with argon as the support gas. Sb(I) emission from an antimony oxide solid powder sample deposited on the thin film was observed primarily in the outer part of the plasma. Analyte emission shows contributions from magnetic compression early in the discharge and from the induced current late in the discharge. The discharge produced analytically useful signals from solid antimony oxide samples. Using spatially and temporally resolved detection, the line-to-background ratio for Sb(I) was found to be greater than 4 for emission integrated from 55 to 120 μs. © 2011 Society for Applied Spectroscopy.
    BibTeX:
    @article{Navarre2011,
      author = {Navarre, E.C. and Goldberg, J.M.},
      title = {Design and characterization of a theta-pinch imploding thin film plasma source for atomic emission spectrochemical analysis},
      journal = {Applied Spectroscopy},
      year = {2011},
      volume = {65},
      number = {1},
      pages = {26--35},
      url = {http://www.ingentaconnect.com/content/sas/sas/2011/00000065/00000001/art00009},
      doi = {http://dx.doi.org/10.1366/10-05706}
    }
    
    Navarre, E.C., Bright, L.K., Osterhage, A. and Lada, B. Development of an N-methyl pyrrolidone based method of analysis for lead in paint 2012 Analytical Methods
    Vol. 4(12), pp. 4295-4302 
    article DOI URL 
    Abstract: A method suitable for the field determination of lead-containing paint by atomic absorption was developed. N-Methyl pyrrolidone (NMP) was used as a pretreatment to soften the paint samples. No heating, mechanical grinding, or other chemical treatments were necessary prior to final sample dilution. Addition of 2% nitric acid was sufficient to dissolve the lead species in as little as 30 minutes. The total sample preparation time was 60 minutes. Using FAAS, ICP-MS, and portable ETAAS, the proposed method was found to give results equivalent to the NIOSH 7082 acid digestion method for a lead paint SRM and several laboratory samples. The proposed method used only two reagents (NMP and dilute nitric acid) to prepare the sample for analysis which makes it specifically suited for determinations performed outside of a traditional laboratory. The presence of NMP in solution required the use of an internal standard to avoid positive bias in ICP-MS analysis. FAAS showed a small negative bias from NMP in solution. Accurate ETAAS determinations required the use of a phosphate matrix modifier. Raman spectroscopy of acidic NMP solutions revealed that the NMP was not chemically degraded under the conditions used for lead determination. However, at higher acid concentrations, loss of the N-methyl was observed.
    BibTeX:
    @article{Navarre2012,
      author = {Navarre, Edward C. and Bright, Leonard Kofi and Osterhage, Amanda and Lada, Bryan},
      title = {Development of an N-methyl pyrrolidone based method of analysis for lead in paint},
      journal = {Analytical Methods},
      publisher = {The Royal Society of Chemistry},
      year = {2012},
      volume = {4},
      number = {12},
      pages = {4295--4302},
      url = {http://xlink.rsc.org/?doi=C2AY25926E},
      doi = {http://dx.doi.org/10.1039/C2AY25926E}
    }
    
    Navarre, E. & Wallace, P. A Non-equilibrium Approach to Temperature Calibration for Tungsten Filament Atomic Spectrometry 2013 Spectroscopy LettersSpectroscopy Letters, pp. -  article DOI  
    Abstract: A non-equilibrium approach voltamperometric temperature measurement for tungsten filament atomizers was developed to facilitate the transfer of thermal conditions between instruments that possess different power supply regulation modes and filaments. Large differences in the equilibrium and instantaneous temperatures were found during the pyrolysis and atomization steps of cadmium AAS analysis. By using the instantaneous temperature, the pyrolysis and atomization behaviors of cadmium were shown to be equivalent regardless of the power supply regulation mode. The pyrolysis conditions optimized for a 15 V filament were readily and accurately transferred to a 12 V filament by applying the non-equilibrium voltamperometric temperature model.
    BibTeX:
    @article{Navarre2013,
      author = {Navarre, Edward and Wallace, Paige},
      title = {A Non-equilibrium Approach to Temperature Calibration for Tungsten Filament Atomic Spectrometry},
      booktitle = {Spectroscopy Letters},
      journal = {Spectroscopy Letters},
      publisher = {Taylor & Francis},
      year = {2013},
      pages = {--},
      doi = {http://dx.doi.org/10.1080/00387010.2013.803980}
    }
    

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