scholarly journals Barometric formula for non-isothermal atmosphere

2021 ◽  
Vol 2131 (2) ◽  
pp. 022053
Author(s):  
E N Bodunov ◽  
GG Khokhlov

Abstract A new barometric formula is derived for a non-isothermal atmosphere. It takes into account the dependence of the acceleration of gravity and gas temperature on the height z above the Earth’s surface. When deriving this formula, it was assumed that the dependence of the gas temperature on altitude is due to the heating of the Earth’s surface by the Sun and the subsequent heat transfer of energy from the Earth’s surface to the atmosphere. The proposed formula coincides with the classical barometric formula for an isothermal atmosphere at low altitudes z, takes into account the experimental linear decrease in the temperature of the atmosphere in its lower layers with increasing altitude z and gives a physically correct asymptotics for the pressure (and for concentration) of the gas as z -> oo, namely, the pressure (and concentration) of gas tends to zero faster than exponentially as z -> oo, which ensures the localization of a finite amount of gas near the Earth.

1997 ◽  
Vol 161 ◽  
pp. 761-776 ◽  
Author(s):  
Claudio Maccone

AbstractSETI from space is currently envisaged in three ways: i) by large space antennas orbiting the Earth that could be used for both VLBI and SETI (VSOP and RadioAstron missions), ii) by a radiotelescope inside the Saha far side Moon crater and an Earth-link antenna on the Mare Smythii near side plain. Such SETIMOON mission would require no astronaut work since a Tether, deployed in Moon orbit until the two antennas landed softly, would also be the cable connecting them. Alternatively, a data relay satellite orbiting the Earth-Moon Lagrangian pointL2would avoid the Earthlink antenna, iii) by a large space antenna put at the foci of the Sun gravitational lens: 1) for electromagnetic waves, the minimal focal distance is 550 Astronomical Units (AU) or 14 times beyond Pluto. One could use the huge radio magnifications of sources aligned to the Sun and spacecraft; 2) for gravitational waves and neutrinos, the focus lies between 22.45 and 29.59 AU (Uranus and Neptune orbits), with a flight time of less than 30 years. Two new space missions, of SETI interest if ET’s use neutrinos for communications, are proposed.


2019 ◽  
Vol 15 (1) ◽  
pp. 73-77
Author(s):  
Valentina V. Ukraintseva ◽  
Keyword(s):  
The Sun ◽  

Author(s):  
David Fisher

There are eight columns in the Periodic Table. The eighth column is comprised of the rare gases, so-called because they are the rarest elements on earth. They are also called the inert or noble gases because, like nobility, they do no work. They are colorless, odorless, invisible gases which do not react with anything, and were thought to be unimportant until the early 1960s. Starting in that era, David Fisher has spent roughly fifty years doing research on these gases, publishing nearly a hundred papers in the scientific journals, applying them to problems in geophysics and cosmochemistry, and learning how other scientists have utilized them to change our ideas about the universe, the sun, and our own planet. Much Ado about (Practically) Nothing will cover this spectrum of ideas, interspersed with the author's own work which will serve to introduce each gas and the important work others have done with them. The rare gases have participated in a wide range of scientific advances-even revolutions-but no book has ever recorded the entire story. Fisher will range from the intricacies of the atomic nucleus and the tiniest of elementary particles, the neutrino, to the energy source of the stars; from the age of the earth to its future energies; from life on Mars to cancer here on earth. A whole panoply that has never before been told as an entity.


Author(s):  
Charles Dickens ◽  
Dennis Walder

Dombey and Son ... Those three words conveyed the one idea of Mr. Dombey's life. The earth was made for Dombey and Son to trade in, and the sun and moon were made to give them light.' The hopes of Mr Dombey for the future of his shipping firm are centred on his delicate son Paul, and Florence, his devoted daughter, is unloved and neglected. When the firm faces ruin, and Dombey's second marriage ends in disaster, only Florence has the strength and humanity to save her father from desolate solitude. This new edition contains Dickens's prefaces, his working plans, and all the original illustrations by ‘Phiz’. The text is that of the definitive Clarendon edition. It has been supplemented by a wide-ranging Introduction, highlighting Dickens's engagement with his times, and the touching exploration of family relationships which give the novel added depth and relevance.


2021 ◽  
pp. 146808742110072
Author(s):  
Karri Keskinen ◽  
Walter Vera-Tudela ◽  
Yuri M Wright ◽  
Konstantinos Boulouchos

Combustion chamber wall heat transfer is a major contributor to efficiency losses in diesel engines. In this context, thermal swing materials (adapting to the surrounding gas temperature) have been pinpointed as a promising mitigative solution. In this study, experiments are carried out in a high-pressure/high-temperature vessel to (a) characterise the wall heat transfer process ensuing from wall impingement of a combusting fuel spray, and (b) evaluate insulative improvements provided by a coating that promotes thermal swing. The baseline experimental condition resembles that of Spray A from the Engine Combustion Network, while additional variations are generated by modifying the ambient temperature as well as the injection pressure and duration. Wall heat transfer and wall temperature measurements are time-resolved and accompanied by concurrent high-speed imaging of natural luminosity. An investigation with an uncoated wall is carried out with several sensor locations around the stagnation point, elucidating sensor-to-sensor variability and setup symmetry. Surface heat flux follows three phases: (i) an initial peak, (ii) a slightly lower plateau dependent on the injection duration, and (iii) a slow decline. In addition to the uncoated reference case, the investigation involves a coating made of porous zirconia, an established thermal swing material. With a coated setup, the projection of surface quantities (heat flux and temperature) from the immersed measurement location requires additional numerical analysis of conjugate heat transfer. Starting from the traces measured beneath the coating, the surface quantities are obtained by solving a one-dimensional inverse heat transfer problem. The present measurements are complemented by CFD simulations supplemented with recent rough-wall models. The surface roughness of the coated specimen is indicated to have a significant impact on the wall heat flux, offsetting the expected benefit from the thermal swing material.


Among the celestial bodies the sun is certainly the first which should attract our notice. It is a fountain of light that illuminates the world! it is the cause of that heat which main­tains the productive power of nature, and makes the earth a fit habitation for man! it is the central body of the planetary system; and what renders a knowledge of its nature still more interesting to us is, that the numberless stars which compose the universe, appear, by the strictest analogy, to be similar bodies. Their innate light is so intense, that it reaches the eye of the observer from the remotest regions of space, and forcibly claims his notice. Now, if we are convinced that an inquiry into the nature and properties of the sun is highly worthy of our notice, we may also with great satisfaction reflect on the considerable progress that has already been made in our knowledge of this eminent body. It would require a long detail to enumerate all the various discoveries which have been made on this subject; I shall, therefore, content myself with giving only the most capital of them.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Kazuo Shiokawa ◽  
Katya Georgieva

AbstractThe Sun is a variable active-dynamo star, emitting radiation in all wavelengths and solar-wind plasma to the interplanetary space. The Earth is immersed in this radiation and solar wind, showing various responses in geospace and atmosphere. This Sun–Earth connection variates in time scales from milli-seconds to millennia and beyond. The solar activity, which has a ~11-year periodicity, is gradually declining in recent three solar cycles, suggesting a possibility of a grand minimum in near future. VarSITI—variability of the Sun and its terrestrial impact—was the 5-year program of the scientific committee on solar-terrestrial physics (SCOSTEP) in 2014–2018, focusing on this variability of the Sun and its consequences on the Earth. This paper reviews some background of SCOSTEP and its past programs, achievements of the 5-year VarSITI program, and remaining outstanding questions after VarSITI.


2012 ◽  
Vol 455-456 ◽  
pp. 284-288
Author(s):  
Wei Li Gu ◽  
Jian Xiang Liu

this paper studies the typical irreversible processes such as combustion and heat transfer with temperature difference based on the theory of thermodynamics, analyzes the influencing factors on exergy loss in irreversible processes, on the basis of this analysis, proposes the energy-saving optimization measures on design and operation management of the organic heat transfer material heater, and specially points out that in the design process, objective function can be constructed with the exergy loss as evaluation index to determine the outlet flue gas temperature of furnace and the flue gas temperature, and provides theoretical basis for the determination of design parameters.


1768 ◽  
Vol 58 ◽  
pp. 156-169 ◽  

It is demonstrated by Sir Isaac Newton in the Principia , that it is not the Earth's center, but the common center of gravity of the Earth and Moon, that describes the ecliptic; and that the Earth and Moon revolve in similar ellipses, about their common center of gravity.


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