![]() Molecular gas is also very sensitive to ultraviolet radiation because the electronic transitions of the most abundant molecules, including H 2, CO, OH, CS, CO 2 +, and C 2, are in this range. Many of the most abundant atoms in the universe emit light in this range when their energy states are changed, up to temperatures as high as a million K (about 1 million☌ or 1.8 million☏), above which x-rays and gamma rays become the main radiation emissions. ![]() Ultraviolet light is more energetic than the visible light our eyes see, possessing a wavelength in the approximate range between approximately 10 and 320 nm. The study of astronomical objects by means of information obtained from the ultraviolet wavelength range of the electromagnetic spectrum. See also: Calendar Celestial mechanics Celestial sphere Earth Earth rotation and orbital motion Equator Seasons Sun Year The summer solstice is the longest day of the year in terms of the greatest sunlight availability for a given hemisphere, while the winter solstice is conversely the shortest day of the year with the least amount of sunlight. ![]() In the Northern Hemisphere, the June event is known as the summer solstice, and the December event, the winter solstice for the Southern Hemisphere, these seasonal attributions are reversed. Many countries in the world use solstices and equinoxes to mark the changing of seasons. The exact date of the solstice varies because the common calendars has only 365 days, but an actual year-a complete revolution around the Sun-is approximately 365.25 days. The annual solstices occur on June 21 or 22, when the North Pole is tilted toward the Sun and on December 21 or 22, when the South Pole is tilted toward the Sun. Defined another way, a solstice occurs when the Sun reaches the farthest point in its path across the sky relative to the celestial equator (a projection of Earth's Equator) on the celestial sphere, with the celestial sphere being an imaginary sphere of infinite radius centered either on an observer or at the center of the Earth. As molecular design is possible, we would like to synthesize carbon with embedded heteroatoms and metal atoms and apply these to other areas, such as catalytic reactions.The two days during the year when the Sun reaches its northernmost or southernmost point in the sky from the Equator. Professor Ogoshi concluded, "Our method is useful, as anyone can synthesize porous carbon with good reproducibility. Porous carbon has more than twice the capacity of graphite, which does not possess sufficiently large pores, indicating that a molecular-level pore diameter is the key to synthesis. This is because the pore size is 4.05 Å, which can fit the sodium ion with a size of 3.8 Å, allowing these ions to pass through the carbon pores. The spacing of the obtained carbon could be controlled at the molecular level, which meant that it could be used as a negative electrode material for sodium-ion batteries. As a result of this process, porous carbon corresponding to the size of the molecule could be obtained. ![]() In specific terms, a network polymer was formed by suitably introducing acetylene with thermal polymerization properties into the aromatic molecule. The research group logically designed the organic molecular skeleton of the carbon source and calcined the organic molecules at 900 ☌ in an inert gas atmosphere to obtain porous carbon with controlled pore diameters at the molecular level. Therefore, it is difficult to control the pores at the molecular level, and advanced technology is required to obtain porous carbon with good reproducibility. However, the structural change in the carbon skeleton during the preparation of the material using this method is significant, such that the original carbon skeleton is not retained. To date, porous carbon has mainly been synthesized via an activation method, in which the carbon skeleton is destroyed by gas or chemicals to form pores. The research group of Professor Tomoki Ogoshi at the Graduate School of Engineering, Kyoto University, Professor Hirotomo Nishihara at the Advanced Institute for Materials Research, Tohoku University, and Professor Yuta Nishina at the Research Core for Interdisciplinary Sciences, Okayama University, developed porous carbon, whose pore size was controlled at the molecular level only by heating.Ī high temperature is required to carbonize organic molecules, the production of porous materials was difficult, and production has been limited owing to high craftsmanship requirements.
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