Laboratory infrared studies relevant to Io: A satellite to the planet Jupiter

To explain the unidentified spectral features of Io, as obtained by the Voyager infrared spectrometer experiment, the infrared absorption spectra of a number of stable sulfur and oxygen compounds was measured and compared to the Voyager data. Based on the reference absorption bands of Na2SO4 and possibly SO2, the infrared data on Io in the region 700 to 200 per cm appear to represent an emission spectrum. Given the strong evidence for an oxidized crustal environment and the presence of sodium in the Io torus, the absorption spectra of the tested materials support the probability of Na2SO4 occurrence on Io

Crystalline sulfur dioxide: Crystal field splittings, absolute band intensities and complex refractive indices derived from infrared spectra

The infrared absorption spectra of thin crystalline films of sulfur dioxide at 90 K are reported in the 2700 to 450/cm region. The observed multiplicity of the spectral features in the regions of fundamentals is attributed to factor group splittings of the modes in a biaxial crystal lattice and the naturally present minor S-34, S-36, and O-18 isotopic species. Complex refractive indices determined by an iterative Kramers-Kronig analysis of the extinction data, and absolute band strengths derived from them, are also reported in this region

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

Analysis of direct CP violation in B−→D0Ds−,D0D−B^- \to D^0 D_s^-, D^0 D^- decays

We investigate the possibility of observing the direct CP violation in the decay modes $B^- \to D^0 D_s^-$ and $D^0 D^-$ within the Standard Model. Including the contributions arising from the tree, annihilation, QCD as well as electroweak penguins with both time- and space-like components, we find that the direct CP asymmetry in $B^- \to D^0 D_s^-$ is very small $\sim 0.2$ % but in $B^- \to D^0 D^-$ decay it can be as large as 4%. Approximately $10^7$ charged $B$ mesons are required to experimentally observe the CP asymmetry parameter for the later case. Since this is easily accessible with the currently running B factories, the decay mode $B^- \to D^0 D^-$ may be pursued to look for CP violation.Comment: Latex, 14 page

Corrosion resistant coating

A method of coating a substrate with an amorphous metal is described. A solid piece of the metal is bombarded with ions of an inert gas in the presence of a magnetic field to provide a vapor of the metal which is deposited on the substrate at a sufficiently low gas pressure so that there is formed on the substrate a thin, uniformly thick, essentially pinhole-free film of the metal

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

A Case Report and Overview of Familial Cerebral Cavernous Malformation Pathogenesis in an Adult Patient

OBJECTIVE We present a case of a 39 year-old woman who presented with a solitary cavernous malformation hemorrhage without any other lesions, and subsequently presented several months later with a new hemorrhage from a de novo lesion. We discuss mechanisms of paradominant inheritance and haploinsufficiency to describe phenotype expression of familial cavernous malformations. CASE DESCRIPTION The patient presented with unremitting headaches, who had a known history of a solitary cerebral cavernous malformation (CCM) for which she underwent resection several months prior with no evidence of any other CCM lesions seen on post-operative MRI. She has no history of whole brain radiation, family history of cavernous malformations, or prior head trauma. During this hospital visit, she was found to have develop two new lesions in the left fronto-parietal lobe and cerebellum. She was treated with surgical resection of the left frontoparietal lesion, and recovered fully. It is of interest that a patient approaching her fourth decade of life would start to develop formation of multiple de novo cavernous malformations, especially with an absent family history. Paradominant Inheritance and haploinsufficiency are two proposed models of inheritance that can be related to this patient’s disease progression. CONCLUSION The case illustrates an atypical clinical course of a patient with familia

Enhancement of drought-induced senescence by the reproductive sink in fertile lines of wheat and Sorghum

The leaf senescence pattern was examined in water-stressed male sterile and fertile lines of wheat (Triticum aestivum) and sorghum (Sorghum vulgare). The study was conducted at the seedling stage and during grain development. The loss of leaf area and chlorophyll content induced by water stress was similar in the male sterile and fertile lines of wheat at the seedling stage. At the grain filling stage, leaf senescence occurred at a faster rate in the fertile lines as compared to sterile lines of both wheat and sorghum. The study indicates that a reproductive sink accentuates drought-induced leaf senescence