University Library, University of Illinois at Urbana-Champaign

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  • PWW Digital Scholarly Publishing Incubation Workshop at the University of Illinois (Fall 2017)
    Scholarship
    Creator
    • Swatscheno, Janet
    • Green, Harriett
    • Bonn, Maria
    • thomas-houston, marilyn
    • Senseney, Megan
    Description
    On October 21, 2017, Publishing Without Walls conducted a day-long incubation workshop on digital scholarly publishing at the University of Illinois at Urbana-Champaign with the goal of engaging with scholars the tools and platform hosted by PWW and opportunities to participate in the PWW initiative.
  • IFSI Newsletter- Fall 2016
    Scholarship
    Creator
    Illinois Fire Service Institute
    Description
    The Illinois Fire Service Institute Newsletter is the official publication of the Illinois Fire Service Institute, University of Illinois at Urbana-Champaign. The newsletter is published twice a year and is solely an educational and advisory aid to the fire service and individuals working to establish and maintain a fire safe environment in Illinois. Opinions expressed in the Illinois Fire Service Institute Newsletter are those of the authors and do not necessarily represent the official opinions of the Illinois Fire Service Institute unless otherwise noted in the article.
  • IFSI Newsletter- Fall 2015
    Scholarship
    Creator
    Illinois Fire Service Institute
    Description
    The Illinois Fire Service Institute Newsletter is the official publication of the Illinois Fire Service Institute, University of Illinois at Urbana-Champaign. The newsletter is published twice a year and is solely an educational and advisory aid to the fire service and individuals working to establish and maintain a fire safe environment in Illinois. Opinions expressed in the Illinois Fire Service Institute Newsletter are those of the authors and do not necessarily represent the official opinions of the Illinois Fire Service Institute unless otherwise noted in the article.
  • IFSI Newsletter- Spring 2010
    Scholarship
    Creator
    Illinois Fire Service Institute
    Description
    The Illinois Fire Service Institute Newsletter is the official publication of the Illinois Fire Service Institute, University of Illinois at Urbana-Champaign. The newsletter is published twice a year and is solely an educational and advisory aid to the fire service and individuals working to establish and maintain a fire safe environment in Illinois. Opinions expressed in the Illinois Fire Service Institute Newsletter are those of the authors and do not necessarily represent the official opinions of the Illinois Fire Service Institute unless otherwise noted in the article.
  • Illinois Fire Service Institute- 2010 Course Calendar
    Scholarship
    Creator
    Illinois Fire Service Institute
    Description
    A calendar of courses offered by the Illinois Fire Service Institute from January 1, 2010, to December 31, 2010.
  • Illinois Fire Service Institute- 2014 Course Calendar
    Scholarship
    Creator
    Illinois Fire Service Institute
    Description
    A calendar of courses offered by the Illinois Fire Service Institute from January 1, 2014, to December 31, 2014.
  • TIPPING THE BALANCE BETWEEN ELECTROSTATICS AND STERIC EFFECTS: THE MICROWAVE SPECTRA AND MOLECULAR STRUCTURES OF...
    Scholarship
    Creator
    Leung, Helen O.
    Description
    We have found that the observed average structures of haloethylene-protic acid heterodimers result from an interplay between favorable electrostatic interactions and steric effects. For vinyl fluoride and 1,1-difluoroethylene complexes, steric effects predominate and the acid binds across the double bond (``top''), while for trifluoroethylene, favorable electrostatics forces the complexes to adopt a sterically strained structure with the acid at one end of the olefin (``side''). A relaxation of steric requirements for binding with a chlorine atom leads to different geometries being observed for each of the vinyl chloride complexes with hydrogen fluoride, hydrogen chloride, and acetylene. The side binding motif to chlorine persists in ({\it Z})-1-chloro-2-fluoroethylene–acetylene despite the presence of the more electronegative fluorine atom. For 2-chloro-1,1-difluoroethylene ethylene–acetylene, the acetylene is presented with the option of top binding to fluorine versus side binding to chlorine, whereas with {\it cis}-1,2-difluoroethylene, the only option is side binding to fluorine. The structures of these two complexes are compared to reveal the balance between electrostatics and sterics.
  • SPECTROSCOPIC CHARACTERIZATION OF SMALL POLAR IMPURITIES IN GASOLINE
    Scholarship
    Creator
    Twagirayezu, Sylvestre
    Description
    Small polar compounds in gasoline have been identified using a BrightSpec Fourier Transform Microwave Rotational Resonance (FT-MRR) spectrometer in the 260-290 GHz band with Headspace Sampling Module. The design of this spectrometer is based on segmented Chirped Pulse Fourier Transform millimeter wave (CP-FTmmW) spectroscopy, which exploits recent advances in digital electronics to allow the measurement of broadband rotational spectra in a few minutes. As part of efforts to determine applications for rotational spectroscopy to petrochemical problems, FT-MRR has been employed to record rotationally resolved spectra of small polar compounds in gasoline. Preliminary analysis of the observed features using the BrightSpec spectral database reveals a rich, but interpretable, pattern, due to the sensitivity of FT-MRR to only polar compounds. The complex hydrocarbon matrix, which in many analytical instruments obscures the signals from low concentration impurities, is nearly invisible in FT-MRR. Spectroscopic and quantitative analyses of detected polar compounds are underway and will be given in this talk.
  • HIGH-RESOLUTION INFRARED SPECTROSCOPY OF ISOPRENE AND METHYL VINYL KETONE IN THE 10 μm REGION
    Scholarship
    Creator
    Stewart, Jacob
    Description
    Isoprene (C$_5$H$_8$) is the most abundant biogenic volatile organic compound (BVOC) emitted by plants into Earth’s atmosphere and plays a key role in the chemistry of the troposphere. Isoprene (and other BVOCs) play a role in the formation of secondary organic aerosols and production of tropospheric ozone, a pollutant that is a major part of photochemical smog. One attractive means of measuring isoprene levels in the atmosphere is the use of infrared spectroscopy to monitor strong absorption bands that lie in the “atmospheric window” between 8-14 $\mu$m. We have measured the high-resolution infrared spectrum of isoprene in the region of the strong \nub{26} vibrational band near 10 $\mu$m using a quantum cascade laser-based spectrometer. This work will support future efforts to use the \nub{26} band for sensing applications. We will discuss the assignment of several weaker bands we have observed near the main \nub{26} band and a rotational analysis based on the strong Q-branches. In addition, we have also observed the high-resolution spectrum of methyl vinyl ketone (C$_4$H$_6$O), an oxidation product of isoprene, in this same frequency region, and will present a preliminary analysis of our spectrum.
  • QUANTITATIVE INFRARED SPECTROSCOPY OF HALOGENATED SPECIES FOR ATMOSPHERIC REMOTE SENSING
    Scholarship
    Creator
    Harrison, Jeremy J.
    Description
    Fluorine- and chlorine-containing molecules in the atmosphere are very strong greenhouse gases, meaning that even small amounts of these gases contribute significantly to the radiative forcing of climate. In addition, a number of these molecules, such as chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), are harmful to the Earth's ozone layer and for this reason their use is regulated by the 1987 Montreal Protocol. The recent Kigali Amendment has added hydrofluorocarbons (HFCs) to the list of controlled substances, coming into effect on 1 January 2019. HFCs, which do not deplete stratospheric ozone, were introduced as refrigerant replacements for CFCs and HCFCs. They are potent greenhouse gases, with global-warming potentials many times greater than carbon dioxide, and are increasing in the atmosphere at a very fast rate. A number of satellite instruments, in particular the ACE-FTS (Atmospheric Chemistry Experiment – Fourier Transform Spectrometer), can monitor many of these species by detecting infrared radiation that has passed through the Earth's atmosphere. However, the quantification of their atmospheric abundances crucially requires accurate quantitative infrared spectroscopy. This talk will focus on new and improved laboratory spectroscopic measurements for a number of important halogenated species.
  • FTMW SPECTRA OF CH3OC(O)NCO AND CH3OC(O)N3
    Scholarship
    Creator
    Watanabe, Shinichiro
    Description
    The rotational spectra of methoxycarbonyl isocyanate ( \chem{CH_3OC(O)NCO}) and methyl azidoformate (\chem{CH_3OC(O)N_3}) in the ground vibrational state were observed by molecular beam-Fourier transform microwave spectroscopy. Observed spectral lines for {\it a}-type transitions were assigned. Splittings of the spectral lines were observed by the internal rotation of the CH$_3$ group and the hyperfine structure of the $^1$$^4$N atom. Comparison of the observed spectroscopic constants with the calculated ones led to the conclusion that the assigned spectrum was due to the {\it syn-syn} form that NCO or N$_3$ group. Determined parameters by the spectral analysis of methoxycarbonyl isocyanate were rotational, centrifugal distortion and nuclear electric quadrupole coupling constants including the potential barrier {\it V}$_3$ to internal rotation of the methyl group. At this stage, we could not analyze the complicate nuclear electric quadrupole coupling splittings of the observed spectrum of methyl azidoformate due to the hyperfine structure.
  • ATTEMPTS TO SOLVE O2-CONTAINING VAN DER WAALS INTERACTIONS USING SPFIT AND SPCAT WITH MICROWAVE MEASUREMENT PRECISION:...
    Scholarship
    Creator
    Grubbs II, G. S.
    Description
    Although there is a vast amount of van der Waals complexes containing small molecular species, there have only been a small number of studies containing an O$_2$ binding partner. Within this grouping, only five are known to have been attempted using high-resolution microwave techniques with only two- O$_2$-HF\footnote{S. Wu, G. Sedo, E. M. Grumstrup, K. R. Leopold, \textit{J. Chem. Phys.}, \textbf{127} (2011) 204315-1-204315-11.} and O$_2$-H$_2$O\footnote{Y. Kasai, E. Dupuy, R. Saito, K. Hashimoto, A. Sabu, S. Kondo, Y. Sumiyoshi, Y. Endo. \textit{Atmos. Chem. Phys.}, \textbf{11} (2011) 8607–8612.}- appearing in the literature. This void is presumably due to the $^3$$\Sigma$ ground state of O$_2$ and how this coupling complicates spectral assignment. However, these sorts of couplings determined from high-resolution analysis add rich and important information useful in complex structure determination. Until now, the only analyses of such complexes have been done utilizing Hund’s case \textit{a} asymmetric models\footnote{W. M. Fawzy, \textit{J. Mol. Spec.}, \textbf{191} (1998) 68-80.}$^,$\footnote{H.-B. Qian, S. J. Low, D. Seccombe, B. Howard, \textit{J. Chem. Phys.}, \textbf{107} (1997) 7651-7657.} or Hund’s case \textit{b} linear Hamiltonians. However, further study either resulted in inaccurate predictions of close transitions (O$_2$-H$_2$O) or difficult adjustments to similar systems due to extra complexity (O$_2$-HCl from O$_2$-HF). This made a more standardized approach, such as using the ubiquitous program suite of SPFIT/SPCAT by Pickett\footnote{H. M. Pickett, \textit{J. Mol. Spec.}, \textbf{148} (1991) 371-377.} seem like a more flexible solution. However, SPFIT/SPCAT uses a Hund’s case \textit{b} approach which needed to be sorted out and the problems and pitfalls of these analyses will be discussed. This talk will include how to be predictive using O$_2$-H$_2$O and O$_2$-HF as examples as well as discuss work currently being pursued on the molecules O$_2$-HCl and O$_2$-OCS to extend the analyses. Structural parameters from these newly determined parameters and their interpretations will also be discussed.
  • RO-VIBRATIONALLY AVERAGED STRUCTURE OF 2Π NCS: RE-INTERPRETATION OF THE B0 VALUES
    Scholarship
    Creator
    Hirano, Tsuneo
    Description
    We have constructed \textit{ab initio} 3D potential energy surfaces (PESs) for $\tilde{X}\;^{2}\Pi$ NCS in core-valence SDCI+$Q$/[aCVQZ(N,C,S)] calculations. The $B_{0}$ value predicted from these PESs deviates only 0.05\%\ from the corresponding experimental values for NC$^{32}$S and NC$^{34}$S. Since we have quite accurate 3D PESs, we can determine both the equilibrium structure and the $r_0$ structure accurately: $r_{\rm e}$(N--C) = 1.1778~\AA, $r_{\rm e}$(C--S) = 1.6335~\AA, and $\angle_{\rm e}$(N--C--S) = 180$^\circ$. The ro-vibrationally averaged structure, determined as expectation values over DVR3D wavefunctions, has $\langle r$(N--C)$\rangle_0$ = 1.1836~\AA, $\langle r$(C--S)$\rangle_0$ = 1.6356~\AA, and $\langle \angle$(N--C--S)$ \rangle_0$ = 172.5$^\circ$. The 3D PESs show that the $\tilde{X}\, ^2\Pi$ NCS has its potential energy minimum at a linear configuration, and hence it is a ``linear molecule.'' Experimentally, $B_{0}$ values are reported for two isotopologues only.\footnote{A.~Maeda, H.~Habara, T.~Amano, {\it Mol. Phys.}, {\bf 105}, 477--495 (2007).} Using the expectation values given above as the initial guess, a bent $r_{0}$ structure having an $\langle \angle$(N--C--S)$ \rangle_0$ of 172.2$^\circ$ is deduced from the experimentally reported $B_{0}$ values for NC$^{32}$S and NC$^{34}$S. It shows that the linear molecule NCS has a ``bent'' ro-vibrationally averaged structure, confirming our previous predictions:\footnote{T.~Hirano, U.~Nagashima, {\it J. Mol. Spectrosc.}, {\bf 314}, 35--47 (2015); % T.~Hirano, U.~Nagashima, P.~Jensen, {\it J. Mol. Spectrosc.} {\bf 343}, 54--61 (2018).} any linear molecule is observed as being bent on ro-vibrational average. See Ref.~$c$ \footnote{T.~Hirano, U.~Nagashima, P.~Jensen, {\it J. Mol. Spectrosc.} (2018), https://doi.org/10.1016/j.jms.2017.12.011.} for further discussion of this molecule. $^{2}\Pi$ NCS is a typical Renner molecule. The Renner spectroscopy of this molecule will be presented in a separate talk.\footnote{J.~Freund et al, ``Computational spectroscopy of NCS in the Renner-degenerate Electronic state $\tilde{X}\, ^2\Pi$.''}
  • COMPARING EXPERIMENTAL AND CALCULATED SPECTRAL PARAMETERS FOR JAHN-TELLER ACTIVE MOLECULES. PART I
    Scholarship
    Creator
    Sharma, Ketan
    Description
    Great advances in quantum chemistry calculations for molecules over the last decade has left a cogent need to make theory testable by experiments. One area of fundamental interest is the computation of both spectroscopic and dynamical properties of molecules near conical intersections between different electronic states. Experiments on naturally occurring and spectroscopically accessible conical intersections in Jahn-Teller molecules provide excellent benchmarks for computations. This talk discusses an approach which allows direct computation of experimental parameters determined from rotationally resolved experiments. An Effective Rotational Hamiltonian (ERH) for Jahn-Teller active system with a $C_3$ or $C_5$ symmetry axis is presented. Methods for calculating the parameters of the ERH using electronic structure and vibrational mode data from coupled cluster calculations are reported. Furthermore theory is advanced to develop a prescription for obtaining observable rovibronic parameters like the rotational distortion parameter, $h_1$, and transition intensities for systems with a $C_3$ and $C_5$ symmetry axis. An important goal of these calculations is to compare experimentally observable parameters to those from highly developed theoretical tools presently available.
  • ROTAMERS OF ISOPRENE: INFRARED SPECTROSCOPY IN HELIUM DROPLETS AND AB INITIO THERMOCHEMISTRY
    Scholarship
    Creator
    Franke, Peter R.
    Description
    Isoprene (\chem{C_5H_8}) is an abundant, reactive tropospheric hydrocarbon, derived from biogenic emissions. A detailed understanding of the spectroscopy of isoprene is therefore desirable. Isoprene monomer is isolated in helium droplets and its infrared spectrum is measured in the CH stretching region. Anharmonic frequencies are predicted by VPT2+K simulations employing CCSD(T) force fields with quadratic (cubic and quartic) force constants computed using the ANO1 (ANO0) basis set. The vast majority of the spectral features can be assigned to trans-isoprene on the basis of these computations. Some features of the higher energy gauche conformer are also assignable, by comparison to experiments using heated isoprene. Convergent ab initio thermochemistry is presented for the isomerization pathway, for which the partition function explicitly accounts for the eigenstates associated with separate, uncoupled one-dimensional potential surfaces for methyl torsion and internal rotation between rotamers. The respective 0 and 298.15 K trans/gauche energy differences are 2.82 and 2.52 kcal/mol, which implies a room temperature gauche population of 2.8\%. Additionally, preliminary spectroscopic results for the OH--$\pi$ complexes between hydroxyl radical and isoprene are presented.
  • ANALYSIS OF THE Ã−X̃ BANDS OF THE ETHYNYL RADICAL NEAR 1.48μm AND RE-EVALUATION OF X̃ STATE ENERGIES
    Scholarship
    Creator
    Gross, Eisen C.
    Description
    We report the observation and analysis of spectra in part of the near-infrared spectrum of C$_2$H, originating in rotational levels in the ground and lowest two excited bending vibrational levels of the ground $\tilde{X}\,^2\Sigma^+$ state. In the analysis, we have combined present and previously reported high resolution spectroscopic data for the lower levels involved in the transitions to determine significantly improved molecular constants to describe the fine and hyperfine split rotational levels of the radical in the zero point, $v_2=1$ and the $^2\Sigma^+$ component of $v_2=2$. Two of the upper state vibronic levels involved, a $^2\Pi$ symmetry level at 6819.3 \wn \, and a $^2\Sigma^+$ one at 7527.1 \wn, \,had not been previously observed. The data and analysis indicate the electronic wavefunction character changes with bending vibrational excitation in the ground state and provide avenues for future measurements of reactivity of the radical as a function of vibrational excitation. \\ Work at Brookhaven National Laboratory was carried out under Contract No. DE-SC0012704 with the U.S. Department of Energy, Office of Science, and supported by its Division of Chemical Sciences, Geosciences and Biosciences within the Office of Basic Energy Sciences.
  • ROTATIONAL SPECTRUM OF METHYL PIVALATE
    Scholarship
    Creator
    Kuze, Nobuhiko
    Description
    The rotational spectrum of methyl pivalate ({\it t}-BuC(O)OCH$_3$) in the ground vibrational state was observed by molecular beam-Fourier transform microwave spectroscopy. Thirty b-type rotational transitions were assigned. Some high-{\it K}$_a$ lines were found to be split and we have interpreted these splittings in terms of the internal rotation of the methyl group. Some forbidden transitions were also observed in case where {\it K}$_a$ = 2 levels were involved in the internal rotation with {\it E} state. The observed spectra including the forbidden transitions were analyzed using XIAM program. Spectral assignment confirmed that the observed spectral splitting was due to the methyl rotation of the methoxy group. In comparison with the theoretical rotational constants, observed rotational constants indicated the molecule took a trans-zigzag conformation for C-C-C-O-C skeleton with {\it C}$_s$ symmetry.
  • DUAL THZ COMB SPECTROSCOPY
    Scholarship
    Creator
    Yasui, Takeshi
    Description
    Optical frequency combs are innovative tools for broadband spectroscopy because a series of comb modes can serve as frequency markers that are traceable to a microwave frequency standard. However, a mode distribution that is too discrete limits the spectral sampling interval to the mode frequency spacing even though individual mode linewidth is sufficiently narrow. Here, using a combination of a spectral interleaving and dual-comb spectroscopy in the terahertz (THz) region, we achieved a spectral sampling interval equal to the mode linewidth rather than the mode spacing. The spectrally interleaved THz comb was realized by sweeping the laser repetition frequency and interleaving additional frequency marks. In low-pressure gas spectroscopy, we achieved an improved spectral sampling density of 2.5MHz and enhanced spectral accuracy of 8.39x10$^{-7}$ in the THz region. The proposed method is a powerful tool for simultaneously achieving high resolution, high accuracy, and broad spectral coverage in THz spectroscopy.
  • OH-π HYDROGEN BOND IN THE COMPLEX OF STYRENE-WATER: A ROTATIONAL STUDY
    Scholarship
    Creator
    Gou, Qian
    Description
    The rotational spectra of the styrene-water complex has been investigated by using the pulsed jet Fourier transform microwave spectroscopic technique. Styrene has two $\pi$ systems which can act as the proton acceptor and link with water through the OH-$\pi$ hydrogen bond. Ab initio calculations suggested that the vinyl $\pi$ system is favored to form such a hydrogen bond. In contrast, the experimental evidences of four isotopologues pointed out that the water O-H group prefers to link to the benzene $\pi$ system. The internal rotation of water around its symmetry axis splits all the rotational transitions into two component line with a relative intensity ration of 1:3.
  • The Comorbidity of Diabetes and Depression among Latinas: A Literature Review
    Scholarship
    Creator
    Quintanilla, Caroline
    Description
    Diabetes remains one of the most prevalent and threatening health disparities in the United States today. Increased societal recognition of depression as a crucial facet of mental health/wellness has presupposed escalating diagnosis rates. Diabetes and depression commonly co-occur and go undetected in primary care settings. Women and Latinos/as have higher rates of either diabetes or depression than non-Hispanic Whites. The aim of the study is to determine the role of diabetes and depression among Latinas in the United States and to determine limitations in existing literature. Expanding integrated health care systems with prevention and treatment programs for diabetes and depression is necessary. This is pertinent to Latinas because of specific factors that impact their likelihood of developing these diseases. Frequent depression screenings throughout the lifespan are warranted to monitor rates of depression. More research must be done to assess the severity of the comorbidity. Through reviewing the literature, it was found the relationship between diabetes and depression among Latinas is bidirectional and more research is necessary to better understand this relationship, which is provoked by factors specific to the Latina lifestyle. There is a lack of research conducted on Latinas and few studies focused on this population.
  • Development of a Geographic Information System for Natural Resources and Recreational Facilities
    Scholarship
    Creator
    • Bayley, Peter B.
    • Joselyn, Mark G.
    • Szafoni, Diane L.
    • Greer, Diane
    • Hunter, Katherine