scholarly journals IR and sub-mm fluxes of SN1987A revisited: when moderate dust masses suffice

2013 ◽  
Vol 9 (S296) ◽  
pp. 392-394
Author(s):  
A. Sarangi ◽  
I. Cherchneff
Keyword(s):  
Chemical Composition ◽  
Chemical Model ◽  
Type Ii ◽  
Chemical Models ◽  
Physico Chemical ◽  
Dust Mass ◽  
Over Time

AbstractWe model the fluxes in the infrared and submillimeter domain using the dust chemical composition and mass derived from the physico-chemical model of a Type II-P supernova ejecta with stellar progenitor of 19 M⊙. Our results highlight that the dust mass predicted to rise over time in our chemical models from 10−2 to 10−1M⊙ satisfactorily reproduce the infrared and sub millimeter fluxes. They confirm that type II-P SNe are efficient but moderate dust makers in galaxies.

scholarly journals Influence of galactic arm scale dynamics on the molecular composition of the cold and dense ISM III. Elemental depletion and shortcomings of the current physico-chemical models

2020 ◽  
Vol 497 (2) ◽  
pp. 2309-2319
Author(s):  
V Wakelam ◽  
W Iqbal ◽  
J-P Melisse ◽  
P Gratier ◽  
M Ruaud ◽  
...  
Keyword(s):  
Gas Phase ◽  
Molecular Form ◽  
Dense Medium ◽  
Chemical Model ◽  
Physical Conditions ◽  
Dense Cores ◽  
Chemical Models ◽  
Physico Chemical ◽  
Galactic Model ◽  
Elemental Depletion

ABSTRACT We present a study of the elemental depletion in the interstellar medium. We combined the results of a Galactic model describing the gas physical conditions during the formation of dense cores with a full-gas-grain chemical model. During the transition between diffuse and dense medium, the reservoirs of elements, initially atomic in the gas, are gradually depleted on dust grains (with a phase of neutralization for those which are ions). This process becomes efficient when the density is larger than 100 cm−3. If the dense material goes back into diffuse conditions, these elements are brought back in the gas phase because of photo-dissociations of the molecules on the ices, followed by thermal desorption from the grains. Nothing remains on the grains for densities below 10 cm−3 or in the gas phase in a molecular form. One exception is chlorine, which is efficiently converted at low density. Our current gas–grain chemical model is not able to reproduce the depletion of atoms observed in the diffuse medium except for Cl, which gas abundance follows the observed one in medium with densities smaller than 10 cm−3. This is an indication that crucial processes (involving maybe chemisorption and/or ice irradiation profoundly modifying the nature of the ices) are missing.

scholarly journals Sorption Characteristics of Bulgarian Penny Buns (Boletus Edulis)

2020 ◽  
Vol 180 ◽  
pp. 03008
Author(s):  
Albena Durakova
Keyword(s):  
Chemical Composition ◽  
Moisture Content ◽  
Model Assessment ◽  
Physico Chemical ◽  
Bet Model ◽  
Monolayer Moisture Content ◽  
Desorption Isotherms ◽  
Monolayer Moisture ◽  
Model Linearization ◽  
Sorption Characteristics

The present study determined the sorption characteristics of Bulgarian penny buns (Boletus) for eight water activities in the 10 % 90 % range and at three temperatures, of 10 °С, 25 °С and 40 °С. The coefficients of the modified Oswin, Chung-Pfost, Halsey and Henderson models were obtained statistically. The modified Halsey model is recommended as a description of adsorption and desorption isotherms since it corresponds to the criteria for model assessment and suitability. Via BET model linearization, the values of the monolayer moisture content for water activity of aw > 0.5 and temperatures of 10 °С, 25 °С and 40 °С were established. The approximate physico-chemical composition of Bulgarian penny buns (Boletus) – moisture content – 10.80 %, protein – 32.23 %, carbohydrate 0.99 %, fat – 6.62 %, ashes – 6.20 % - was also determined.

scholarly journals Kwestia chronologii, typologii i pochodzenia szklanej biżuterii z wczesnośredniowiecznego ośrodka grodowego w Gnieźnie

2020 ◽  
Vol 25 ◽  
pp. 247-289
Author(s):  
Joanna Sawicka
Keyword(s):  
Comparative Analysis ◽  
Chemical Composition ◽  
Glass Composition ◽  
Starting Material ◽  
14C Dating ◽  
Glass Strip ◽  
X Ray ◽  
General Manner ◽  
Physico Chemical ◽  
Early Settlement

The study presents 175 artefacts from the settlement center in Gniezno – beads and rings. The materials come from settlement levels from around the mid-10th to the 13th centuries. The latest chronological findings based on 14C dating have made it possible to refine the dating, especially of the early settlement levels of the stronghold, where the vast majority of glass artefacts come from. Threeba sic groups of beads have been distinguished based on the technique of their production – beads made of a drawing a tube, the technique of winding a glass strip, as well as casting and sintering. The results of 7 physico-chemical analyzes of the glass composition (performed with the X-Ray Fluorescence, XRF method) are presented. Physicochemical analyzes of the chemical composition of the tested beads made it possible to determine the technological group and the type of glass. An attempt was made to explain the origin of the starting material (glass) for jewelery. A comparative analysis made it possible to indicate in a general manner possible manufacturers and to outline the likely directions of the influx of these glass ornaments to Gniezno.

scholarly journals Isolation, chemical composition, and molecular size of extracellular type II and type Ia polysaccharides of group B streptococci.

1983 ◽  
Vol 41 (2) ◽  
pp. 527-534 ◽  
Author(s):  
B J De Cueninck ◽  
T F Greber ◽  
T K Eisenstein ◽  
R M Swenson ◽  
G D Shockman
Keyword(s):  
Chemical Composition ◽  
Molecular Size ◽  
Type Ii ◽  
Group B Streptococci ◽  
Type Ia ◽  
Group B

scholarly journals An improved physico-chemical model of hybridization on high-density oligonucleotide microarrays

2008 ◽  
Vol 24 (10) ◽  
pp. 1278-1285 ◽  
Author(s):  
N. Ono ◽  
S. Suzuki ◽  
C. Furusawa ◽  
T. Agata ◽  
A. Kashiwagi ◽  
...  
Keyword(s):  
High Density ◽  
Chemical Model ◽  
Oligonucleotide Microarrays ◽  
Physico Chemical
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