7,638 research outputs found
Absorption and resonance Raman spectra of Pb2, Pb3 and Pb4 in xenon matrices
Lead metal was vaporized and trapped in solid xenon at 12K. Electronic absorption and resonance Raman spectra were recorded of the resulting matrix, which was shown to contain Pb2, Pb3, and possibly Pb4 molecular species. The vibrational frequency for Pb2 is determined to be 108/cm for the ground state, with a dissociation energy of 82000/cm. Ad3h symmetry is indicated for the Pb3 species, with nu sub 1=117/cm and nu sub 2 = 96 /cm. The existence of Pb4 is suggested by a fundamental and overtone of 111/cm spacing
A spectroscopic study of intermediates in the condensation of refractory smokes: Matrix isolation experiments SiO
The infrared and Raman spectra of N2 matrix isolated silicon oxides are investigated. The vibrational frequencies of SiO, Si2O2, and Si3O3 were identified and assigned on the basis of normal coordinate analyses. Heating the solid to 50 K (evaporating the matrix) leaves a residue whose infrared spectrum is identical to that of a smoke condensed at ambient temperatures. Further heating of the sample to 500 K leads to significant changes in the band shapes. Investigations of the infrared spectra at several stages of the diffusion process result in the proposal of a mechanism for the transition from molecular properties to those of the residue (bulk) material, which is characterized as Si2O3
Collision of spinning black holes in the close limit
In this paper we consider the collision of spinning holes using first order
perturbation theory of black holes (Teukolsky formalism). With these results
(along with ones, we published in the past) one can predict the properties of
the gravitational waves radiated from the late stage inspiral of two spinning,
equal mass black holes. Also we note that the energy radiated by the head-on
collision of two spinning holes with spins (that are equal and opposite)
aligned along the common axis is more than the case in which the spins are
perpendicular to the axis of the collision.Comment: 6 pages, 3 figures, submitted to PR
Markers of Oxidative Stress in Generalized Anxiety Psychiatric Disorder: Therapeutic Implications
There is growing evidence that oxidative stress contributes to the pathogenesis of anxiety disorders. Our aim was to measure oxidative stress in anxiety disorders subjects, and assesses the potential confounding influences of anti anxiety therapy. Serum malondialdehyde and antioxidant levels were estimated in patients at the time of presentation and also after anti- anxiety therapy for 3 months. During the period of study no antioxidant/s was given to the patients and control subjects. Serum malondialdehyde levels were significantly higher in the anxiety disorders patients in comparison to control cases. Also, the antioxidant activity of enzymes super oxide dismutase, glutathione and non enzymatic antioxidant levels of vitamins E and C were significantly lower in patients compared to controls at the initial presentation. After 3 months of anti anxiety treatment all the above parameters showed reversal in the respective levels of serum malondialdehyde and antioxidant activity. Anti anxiety medications results in reduced oxidative stress which indicates that oxidative stress is not the cause, but rather a consequence, of anxiety disorders
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Energy and CO2 implications of decarbonization strategies for China beyond efficiency: Modeling 2050 maximum renewable resources and accelerated electrification impacts
Energy efficiency has played an important role in helping China achieve its domestic and international energy and climate change mitigation targets, but more significant near-term actions to decarbonize are needed to help China and the world meet the Paris Agreement goals. Accelerating electrification and maximizing supply-side and demand-side renewable adoption are two recent strategies being considered in China, but few bottom-up modeling studies have evaluated the potential near-term impacts of these strategies across multiple sectors. To fill this research gap, we use a bottom-up national end-use model that integrates energy supply and demand systems and conduct scenario analysis to evaluate even lower CO2 emissions strategies and subsequent pathways for China to go beyond cost-effective efficiency and fuel switching. We find that maximizing non-conventional electric and renewable technologies can help China peak its national CO2 emissions as early as 2025, with significant additional CO2 emission reductions on the order of 7 Gt CO2 annually by 2050. Beyond potential CO2 reductions from power sector decarbonization, significant potential lies in fossil fuel displaced by renewable heat in industry. These results suggest accelerating the utilization of non-conventional electric and renewable technologies present additional CO2 reduction opportunities for China, but new policies and strategies are needed to change technology choices in the demand sectors. Managing the pace of electrification in tandem with the pace of decarbonization of the power sector will also be crucial to achieving CO2 reductions from the power sector in a scenario of increased electrification
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