Energy & Green Tech
An electrode coating just one molecule thick can significantly enhance the performance of an organic photovoltaic cell, KAUST researchers have found. The coating outperforms the leading material currently used for this task ...
Jun 10, 2021
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Energy & Green Tech
A new technology could dramatically improve the safety of lithium-ion batteries that operate with gas electrolytes at ultra-low temperatures. Nanoengineers at the University of California San Diego developed a separator—the ...
Jun 7, 2021
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Energy & Green Tech
A compound used widely in candles offers promise for a much more modern energy challenge—storing massive amounts of energy to be fed into the electric grid as the need arises.
May 20, 2021
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Robotics
Research focusing on swarm robotics typically uses theoretical approaches to describe robotic systems in an abstract way. A theoretical model that is often used in robotics studies is OBLOT, an approach that represents robots ...
Computer Sciences
A year into the COVID-19 pandemic, mass vaccinations have begun to raise the tantalizing prospect of herd immunity that eventually curtails or halts the spread of SARS-CoV-2. But what if herd immunity is never fully achieved—or ...
May 3, 2021
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Electronics & Semiconductors
How can I prepare myself for something I do not yet know? Scientists from the Fritz Haber Institute in Berlin and from the Technical University of Munich have addressed this almost philosophical question in the context of ...
Apr 23, 2021
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103
Computer Sciences
Artificial intelligence is now capable of generating novel, functionally active proteins, thanks to recently published work by researchers from Chalmers University of Technology, Sweden.
Mar 30, 2021
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141
Electronics & Semiconductors
In the future, photovoltaic cells could be 'worn' over clothes, placed on cars or even on beach umbrellas. These are just some of the possible developments from a study published in Nature Communications by researchers at ...
Mar 25, 2021
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Energy & Green Tech
Afew years ago, Harvard chemist Daniel Nocera, along with collaborators from Harvard Medical School, created a system that uses sunlight to split water molecules and combine them with carbon dioxide from air to produce renewable ...
Mar 22, 2021
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16
Energy & Green Tech
Monitoring the health of flow batteries in real time is a challenge. Argonne researchers have designed a fluorescent molecule for the purpose.
Feb 3, 2021
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A molecule is defined as a sufficiently stable, electrically neutral group of at least two atoms in a definite arrangement held together by very strong (covalent) chemical bonds. Molecules are distinguished from polyatomic ions in this strict sense. In organic chemistry and biochemistry, the term molecule is used less strictly and also is applied to charged organic molecules and biomolecules.
In the kinetic theory of gases the term molecule is often used for any gaseous particle regardless of its composition. According to this definition noble gas atoms are considered molecules despite the fact that they are composed of a single non-bonded atom.
A molecule may consist of atoms of a single chemical element, as with oxygen (O2), or of different elements, as with water (H2O). Atoms and complexes connected by non-covalent bonds such as hydrogen bonds or ionic bonds are generally not considered single molecules.
No typical molecule can be defined for ionic crystals (salts) and covalent crystals (network solids), although these are often composed of repeating unit cells that extend either in a plane (such as in graphene) or three-dimensionally (such as in diamond or sodium chloride). The theme of repeated unit-cellular-structure also holds for most condensed phases with metallic bonding. In glasses (solids that exist in a vitreous disordered state), atoms may also be held together by chemical bonds without any definable molecule, but also without any of the regularity of repeating units that characterises crystals.
This text uses material from Wikipedia, licensed under CC BY-SA
