204 research outputs found
Habitable Zones and UV Habitable Zones around Host Stars
Ultraviolet radiation is a double-edged sword to life. If it is too strong,
the terrestrial biological systems will be damaged. And if it is too weak, the
synthesis of many biochemical compounds can not go along. We try to obtain the
continuous ultraviolet habitable zones, and compare the ultraviolet habitable
zones with the habitable zones of host stars. Using the boundary ultraviolet
radiation of ultraviolet habitable zone, we calculate the ultraviolet habitable
zones of host stars with masses from 0.08 to 4.00 \mo. For the host stars with
effective temperatures lower than 4,600 K, the ultraviolet habitable zones are
closer than the habitable zones. For the host stars with effective temperatures
higher than 7,137 K, the ultraviolet habitable zones are farther than the
habitable zones. For hot subdwarf as a host star, the distance of the
ultraviolet habitable zone is about ten times more than that of the habitable
zone, which is not suitable for life existence.Comment: 5 pages, 3 figure
Habitable Zones of Host Stars During the Post-MS Phase
A star will become brighter and brighter with stellar evolution, and the
distance of its habitable zone will become farther and farther. Some planets
outside the habitable zone of a host star during the main sequence phase may
enter the habitable zone of the host star during other evolutionary phases. A
terrestrial planet within the habitable zone of its host star is generally
thought to be suited to life existence. Furthermore, a rocky moon around a
giant planet may be also suited to life survive, provided that the planet-moon
system is within the habitable zone of its host star. Using Eggleton's code and
the boundary flux of habitable zone, we calculate the habitable zone of our
Solar after the main sequence phase. It is found that Mars' orbit and Jupiter's
orbit will enter the habitable zone of Solar during the subgiant branch phase
and the red giant branch phase, respectively. And the orbit of Saturn will
enter the habitable zone of Solar during the He-burning phase for about 137
million years. Life is unlikely at any time on Saturn, as it is a giant gaseous
planet. However, Titan, the rocky moon of Saturn, may be suitable for
biological evolution and become another Earth during that time. For low-mass
stars, there are similar habitable zones during the He-burning phase as our
Solar, because there are similar core masses and luminosities for these stars
during that phase.Comment: 6 pages, 7 figures. Accepted by Ap & S
Numerical Simulation of Flare Burning of Coal of a Micro-Mill in a Steam-Oil Burner
Статья посвящена численному моделированию факельного сжигания угольного
топлива в паромасляной горелке. Представлены результаты моделирования паромасляной
горелки, разработанной в ИТ СО РАН, и новой факельной горелки, работающей на дизельном
топливе с частичной заменой его на уголь микропомола. Сравнение результатов расчета
с данными эксперимента показало их хорошее соответствие, как по уровню температуры, так
и по концентрации газовых компонент продуктов горения. Результаты моделирования показали,
что новая горелка устойчиво работает в широком диапазоне расхода угольной пыли. Полученные
результаты численного исследования можно использовать при проектировании нового горелочного
устройства, подобрав оптимальные режимы работы, для снижения на выходе концентрации
вредных выбросов и недожега топливаThe article is devoted to numerical modeling of coal fuel flaring in a steam-oil burner. The results of modeling an oil-steam burner developed at IT SB RAS and a new torch burner operating on diesel fuel with partial replacement of it with micro-milled coal are presented. A comparison of the calculation results with the experimental data showed their good agreement both in terms of the temperature level and the concentration of the gas components of the combustion products. The simulation results showed that the new burner operates stably in a wide range of pulverized coal flow rates. The obtained results of a numerical study can be used in the design of a new burner device, choosing the optimal operating modes to reduce the concentration of harmful emissions and fuel underburning at the outpu
Abstracts of presentations on plant protection issues at the fifth international Mango Symposium Abstracts of presentations on plant protection issues at the Xth international congress of Virology: September 1-6, 1996 Dan Panorama Hotel, Tel Aviv, Israel August 11-16, 1996 Binyanei haoma, Jerusalem, Israel
Development of a construct-based risk assessment framework for genetic engineered crops
Biotechnological approaches for plant viruses resistance: from general to the modern RNA silencing pathway
Adrift [Album]
‘Adrift’ album by Sam Leak & Dan Tepfer, released by Jellymould Jazz, November 2018
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