26 research outputs found
THE FAR INFRARED SPECTRUM OF BETWEEN 80 AND .
Author Institution: Department of Chemistry, University of CaliforniaTwo new intermolecular vibrations of have been observed by tunable for infrared laser spectroscopy in a planar jet. So far, 288 absorption lines between 80 and have been assigned to 32 subbands of the two vibrations. One vibration has b-type (out-of-plane) selection rules and is assigned as a torsion about the intermolecular bond axis. The other has a-type (in-plane) selection rules and is tentatively assigned as the `geared’ in-plane bend, or equivalently, the second overtone of `donor’ - `acceptor’ interchange. The vibrational assignments of the new spectra and the proton tunneling dynamics in the excited states will be discussed
OBSERVATION OF A NEW VIBRATIONAL MODE OF NEAR USING TUNABLE FAR-INFRARED LASER SPECTROSCOPY
1. N.P. Pugliano, J.D. Cruzan, J.G. Loeser and R.J. Saykally, J. Chem. Phys., 98, 6600 (1992). 2. For example S.C. Althorpe and D.C. Clary, J. Chem. Phys., 101, 3603 (1994).Author Institution: University of California at Berkeley, Berkeley, CA 94720We have measured the far-infrared vibration-rotation-tunneling (VRT) spectrum of an intermolecular vibration of near . In addition, further transitions of the VRT band of previously reported by have been observed. By considering symmetry restraints on the selection rules, these bands have been assigned to the out-of-plane H-bond torsional and in-plane acceptor waggins modes predicted by many theoretical The experimental-theoretical discrepancy in the measured frequencies of these bands indicates the importance of a fully coupled six-dimmensional calculation of the dynamics for the water dimer
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Definitive design status of the SP-100 Ground Engineering System Test Site
The SP-100 reactor will be ground tested at the SP-100 Ground Engineering System (GES) Test Site on the US Department of Energy (DOE) Hanford Site near Richland, Washington. Project direction and the flight system design evolution have resulted in a smaller reactor size and the consequential revision to Test Site features to accommodate the design changes and reduce Test Site costs. The significant design events since the completion of the Conceptual Design are discussed in this paper
Explanation of Change (EoC) Study: Considerations and Implementation Challenges
This paper discusses the implementation of considerations resulting from a study investigating the cost change experienced by historical NASA science missions. The study investigated historical milestone and monthly status report documentation followed by interviews with key project personnel. The reasons for cost change were binned as being external to NASA, external to the project and internal to the project relative to the project's planning and execution. Based on the results of the binning process and the synthesis of project meetings and interviews, ten considerations were made with the objective to decrease the potential for cost change in future missions. Although no one magic bullet consideration was discovered, the considerations taken as a whole should help reduce cost and schedule change in future NASA missions
Discovery of methanimine (CH2NH) megamasers toward compact obscured galaxy nuclei
We present the first search for the 5.29 GHz methanimine (CH2NH) 110 - 111 transition toward a sample of galaxy nuclei. We target seven galaxies that host compact obscured nuclei (CONs) with the Karl G. Jansky Very Large Array. These galaxies are characterized by Compton-thick cores. CH2NH emission is detected toward six CONs. The brightness temperatures measured toward Arp 220 indicate maser emission. Isotropic luminosities of the CH2NH transition, from all sources where it is detected, exceed 1 Lpdbl and thus may be considered megamasers. We also detect formaldehyde (H2CO) emission toward three CONs. The isotropic CH2NH luminosities are weakly correlated with the infrared luminosity of the host galaxy and strongly correlated with OH megamaser luminosities from the same galaxies. Non-local thermodynamic equilibrium radiative transfer models suggest that the maser is pumped by the intense millimeter-to-submillimeter Our study suggests that CH2NH megamasers are linked to the nuclear processes within 100 pc of the Compton-thick nucleus within CONs
Dispersed Water and Particulates in Jet Fuel: Size Analysis under Operational Conditions and Application to Coalescer Disarming
Large-Scale Biophysical Evaluation of Protein PEGylation Effects: In Vitro Properties of 61 Protein Entities
PEGylation is the
most widely used method to chemically modify
protein biopharmaceuticals, but surprisingly limited public data is
available on the biophysical effects of protein PEGylation. Here we
report the first large-scale study, with site-specific mono-PEGylation
of 15 different proteins and characterization of 61 entities in total
using a common set of analytical methods. Predictions of molecular
size were typically accurate in comparison with actual size determined
by size-exclusion chromatography (SEC) or dynamic light scattering
(DLS). In contrast, there was no universal trend regarding the effect
of PEGylation on the thermal stability of a protein based on data
generated by circular dichroism (CD), differential scanning calorimetry
(DSC), or differential scanning fluorimetry (DSF). In addition, DSF
was validated as a fast and inexpensive screening method for thermal
unfolding studies of PEGylated proteins. Multivariate data analysis
revealed clear trends in biophysical properties upon PEGylation for
a subset of proteins, although no universal trends were found. Taken
together, these findings are important in the consideration of biophysical
methods and evaluation of second-generation biopharmaceutical drug
candidates