First high-resolution infrared spectra of 2–13C-propane:Analyses of the ν26 (B2) c-type and ν9 (A1) b-type bands

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Molecular structures of gas‐phase polyatomic molecules determined by spectroscopic methods

Spectroscopic data related to the structures of polyatomic molecules in the gas phase have been reviewed, critically evaluated, and compiled. All reported bond distances and angles have been classified as equilibrium (re), average (rz), substitution (rs), or effective (ro) parameters, and have been given a quality rating which is a measure of the parameter uncertainty. The surveyed literature includes work from all of the areas of gas‐phase spectroscopy from which precise quantitative structural information can be derived. Introductory material includes definitions of the various types of parameters and a description of the evaluation procedure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87746/2/619_1.pd

Hadron Production in Diffractive Deep-Inelastic Scattering

Characteristics of hadron production in diffractive deep-inelastic positron-proton scattering are studied using data collected in 1994 by the H1 experiment at HERA. The following distributions are measured in the centre-of-mass frame of the photon dissociation system: the hadronic energy flow, the Feynman-x (x_F) variable for charged particles, the squared transverse momentum of charged particles (p_T^{*2}), and the mean p_T^{*2} as a function of x_F. These distributions are compared with results in the gamma^* p centre-of-mass frame from inclusive deep-inelastic scattering in the fixed-target experiment EMC, and also with the predictions of several Monte Carlo calculations. The data are consistent with a picture in which the partonic structure of the diffractive exchange is dominated at low Q^2 by hard gluons.Comment: 16 pages, 6 figures, submitted to Phys. Lett.

Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

First High-Resolution Analysis of the Absorption Spectrum of Propane in the 6.7-7.5 μm Spectral Region

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Resolved Torsional Splittings in the ν18 and ν19- Bands of Propene

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Infrared Spectrum of OClO in the 2000 cm-1Region: The 2ο1 and ο1 + ο3 Bands

The FTIR spectra of the 2ο1 and ο1 + ο3 bands of ClO2 (OClO) have been recorded in the 2000 cm-1 region. with an instrumental resolution of ∿0.004 cm-1. The spectra have been analyzed using a Hamiltonian which includes spin-rotation terms to provide the first high-resolution analysis of these bands. Around 1900 transitions of 35ClO2 (plus ∿600 of 37ClO2) have been assigned in 2ο1, and 1100 transitions of 35ClO2 (plus ∿450 of 37ClO2) have been identified in ο1 + ο3. By making use of all available data, accurate band centers, rotational constants, spin rotational constants. and a number of the xrs anharmonicity constants as well as α and γ parameters have been obtained. © 1993 Academic Press. All rights reserved.Peer Reviewe

HIGH RESOLUTION INFRARED SPECTRUM OF ETHYLENE (12^{12}C2_2H4_4) IN THE SPECTRAL REGION 1820 TO 2300 CM−1^{-1}

Author Institution: Laboratoire Interuniversitaire des Systemes Atmospheriques, C.N.R.S., UMR 7583, Universites Paris Est et 7, 61 Avenue du General de Gaulle, 94010 Creteil Cedex France; Optical Technology Division, National Institue of Standards and Technology, Gaithersburg, MD 20899-8441, USAWhile the fundamental bands of ethylene have been studied at high resolution, most of the combination bands have not been recorded. In this study, we have recorded the $^{12}$C$_2$H$_4$ bands in the 1820 to 2300 cm$^{-1}$ region which consists of a myriad of weak combination bands. Over 10,000 lines were measured. The strongest of these bands are the A-type band, \nu$_7$+\nu$_8$ , centered at 1889 cm$^{-1}$, the A-type band, \nu$_6$+\nu$_1$$_0$ , at 2048 cm$^{-1}$, and the B-type band, \nu$_3$+\nu$_1$_0$, at 2173 cm$^{-1}$. In addition, there are numerous lines from much weaker bands. All the bands observed are perturbed by Coriolis interactions, and, at this point, we are attempting to fit all the lines to within experimental error using an Hamiltonian matrix including eigth vibrational states among which four are dark states . The most striking resonance is that of the \nu$_7$+\nu$_8$band whose energy levels are crossed by the very much weaker \nu$_4$+\nu$_8$ band where the intensities of the K=7 lines are enhanced due to mixing with the stronger band