Physical and Chemical Composition of Comets — From Interstellar Space to the Earth

1993 ◽  
pp. 195-207 ◽  
Author(s):  
J. Mayo Greenberg
1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.


2010 ◽  
Vol 13 (3) ◽  
pp. 29-38
Author(s):  
Ha Bich Phan ◽  
Thach Ngoc Le

Coriandrum sativum L. belongs to the Apiaceae family, which is cultivated in Dong Nai province, in this paper its seed oil of was studied. The essential oil was extracted by hydrodistillation. We used two methods for activating of hydrodistillation: conventional heating and microwave irradiating. Its physical and chemical indexes were measured. The chemical composition of this oil was identified by GC/MS and quantified by GC/FID. Linalool (75.51-77.21 %), and geranyl acetate (15.64-12.79 %) were the main constituents of the oil which were obtained in 0,32-0.39 % yield. The biological activity of this oil was reported.


2018 ◽  
Vol 20 (6) ◽  
pp. 24-25
Author(s):  
E.O. Kachanova ◽  
◽  
E.V. Pavlova ◽  
D.S. Derina ◽  
◽  
...  

2007 ◽  
Vol 6 (sup2) ◽  
pp. 1067-1070 ◽  
Author(s):  
M. A. S. Khan ◽  
M. N. Islam ◽  
M. S. R. Siddiki

Author(s):  
G.J.F. Assis ◽  
L.A. Godoi ◽  
S.C. Valadares Filho ◽  
B.C. Silva ◽  
D.E.F. Assis ◽  
...  

1996 ◽  
Vol 61 (1) ◽  
pp. 253-257 ◽  
Author(s):  
FERMIN AZANZA ◽  
BARBARA P. KLEIN ◽  
JOHN A. JUVIK

2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Kamalasan Prathap- Mathan ◽  
Joseph Babila- Jasmine ◽  
Muthukumar Thilagavathi

Water is the most abundant and non-renewable resource in the earth, which play an important role in all living organisms. A study on physiochemical parameters of Manur, Vallanadu and Sundarapandiapatinam ponds from Tirunelveli, Thootukudi and Ramanathapuram districts of Tamil Nadu, India, has addressed the seasonal changes. During the month of January to April samples from Manur was chemically portable, Vallanadu sample was physically portable, Sundarapandiapatinam samples were physically and chemically not portable. During the month of May to August Vallanadu and Manur samples were portable by its physical and chemical examination, Sundarapandiapatinam samples were non portable by its physiochemical property. September to December the samples from all the three ponds were non portable because of exceeding the permissible limit. All the samples were bacteriologically unsafe in nature because of its microbial contamination. This implies the water bodies are not fit for domestic and drinking purpose, thus proper management has to be done by the society and implement government guidelines to save the natural resources from manmade activities.


2016 ◽  
Vol 18 (4) ◽  
pp. 106-112
Author(s):  
T. Fotina ◽  
◽  
N. Zazharska ◽  

Author(s):  
Jan Zalasiewicz ◽  
Mark Williams ◽  
Richard Fortey ◽  
Alan Smith ◽  
Tiffany L. Barry ◽  
...  

The Anthropocene, an informal term used to signal the impact of collective human activity on biological, physical and chemical processes on the Earth system, is assessed using stratigraphic criteria. It is complex in time, space and process, and may be considered in terms of the scale, relative timing, duration and novelty of its various phenomena. The lithostratigraphic signal includes both direct components, such as urban constructions and man-made deposits, and indirect ones, such as sediment flux changes. Already widespread, these are producing a significant ‘event layer’, locally with considerable long-term preservation potential. Chemostratigraphic signals include new organic compounds, but are likely to be dominated by the effects of CO 2 release, particularly via acidification in the marine realm, and man-made radionuclides. The sequence stratigraphic signal is negligible to date, but may become geologically significant over centennial/millennial time scales. The rapidly growing biostratigraphic signal includes geologically novel aspects (the scale of globally transferred species) and geologically will have permanent effects.


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