Spectroscopic Observation of the STARDUST Re-Entry in the Near UV

2007 ◽  
Author(s):  
Michael Winter ◽  
Georg Herdrich
Keyword(s):  
Spectroscopic Observation

scholarly journals Estimation of bulk permittivity of the Moon’s surface using Lunar Radar Sounder on-board Selenological and Engineering Explorer

2020 ◽  
Vol 72 (1) ◽  
Author(s):  
Keigo Hongo ◽  
Hiroaki Toh ◽  
Atsushi Kumamoto
Keyword(s):  
Electrical Conductivity ◽  
Physical Properties ◽  
Titanium Content ◽  
Spectroscopic Observation ◽  
Lunar Rock ◽  
Almost All ◽  
Mare Serenitatis ◽  
Radar Sounder ◽  
Lunar Maria ◽  
Regolith Layer

Abstract Site-dependent bulk permittivities of the lunar uppermost media with thicknesses of tens to hundreds meters were estimated based on the data from Lunar Radar Sounder onboard the Selenological and Engineering Explorer (SELENE). It succeeded in sounding almost all over the Moon’s surface in a frequency range around 5 MHz to detect subsurface reflectors beneath several lunar maria. However, it is necessary to estimate the permittivity of the surface regolith of the Moon in order to determine the actual depths to those reflectors instead of apparent depths assuming a speed of light in the vacuum. In this study, we determined site-dependent bulk permittivities by two-layer models consisting of a surface regolith layer over a half-space with uniform, but different physical properties from the layer above. Those models consider the electrical conductivity as well as the permittivity, whose trade-off was resolved by utilizing the correlation between iron–titanium content and measured physical properties of lunar rock samples. Distribution of the iron–titanium content on the Moon’s surface had already been derived by spectroscopic observation from SELENE as well. Four lunar maria, Mare Serenitatis, Oceanus Procellarum, Mare Imbrium, and Mare Crisium, were selected as regions of evident reflectors, where we estimated the following four physical properties of each layer, i.e., bulk permittivity, porosity, loss tangent and electrical conductivity to conclude the actual depths of the reflectors are approximately 200 m on average. The bulk permittivity ranges from 2.96 at Mare Imbrium to 6.37 at Oceanus Procellarum, whereas the porosity takes the values between 1.8 and 41.1% in the respective maria. It was found that although the bulk permittivity of the four lunar maria differs from a mare to a mare, it shows a good correlation with their composition, viz., their iron–titanium content.

Micro-Raman Spectroscopic Observation of Water Expulsion Induced Destruction of Hydrophobic Clusters in Crystalline Lysozyme

2009 ◽  
Vol 113 (29) ◽  
pp. 9633-9635 ◽  
Author(s):  
Jing-Jing Shou ◽  
Guang Zeng ◽  
Yun-Hong Zhang ◽  
G. Q. (Max) Lu
Keyword(s):  
Spectroscopic Observation ◽  
Raman Spectroscopic

scholarly journals Tridimensional Spectroscopic Observation of the Interacting System NGC 7592

2002 ◽  
Vol 54 (3) ◽  
pp. 393-404 ◽  
Author(s):  
Takashi Hattori ◽  
Michitoshi Yoshida ◽  
Hiroshi Ohtani ◽  
Tsuyoshi Ishigaki ◽  
Hajime Sugai ◽  
...  
Keyword(s):  
Spectroscopic Observation

In situ Raman Spectroscopic Observation of Polymer Chains in Semi-Crystalline Polyethylene Solids

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Yusuke Hiejima ◽  
Takumitsu Kida ◽  
Koh-hei Nitta
Keyword(s):  
Conformational Changes ◽  
Tensile Elongation ◽  
Spectroscopic Observation ◽  
Polymer Chains ◽  
Trans Conformation ◽  
Raman Spectroscopic ◽  
Higher Temperature ◽  
Microscopic Origin ◽  
Crystalline Polyethylene

AbstractIn situ Raman spectroscopy is applied for polyethylene solid under various environments to elucidate the morphological and conformational changes. The trans conformation retains up to higher temperature for high-density polyethylene, reflecting higher stability of the orthorhombic crystals composed of stacked trans chains. It is suggested that the conversion of the non-crystalline trans chains to the crystalline phase is the microscopic origin of thermal history in the crystallinity, whereas the transformation between the trans and gauche conformers is practically in thermal equilibrium. Microscopic and dynamic mechanism of deformation during uniaxial stretching is investigated for the molecular orientation and the microscopic load sharing on the crystalline and amorphous chains. Lower crystallinity results in smoother and higher orientation toward the stretching direction, as well as higher load on the amorphous chains, during tensile elongation.

scholarly journals Spectroscopic observation of HCl degassing from Soufriere Hills Volcano, Montserrat

1998 ◽  
Vol 25 (19) ◽  
pp. 3689-3692 ◽  
Author(s):  
Clive Oppenheimer ◽  
Peter Francis ◽  
Adam J. H. Maciejewski
Keyword(s):  
Spectroscopic Observation ◽  
Soufriere Hills Volcano ◽  
Soufrière Hills Volcano ◽  
Soufriere Hills
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