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Nuclear Energy Science Tracer Bullet (Library of Congress)
Nuclear Power (Wolfram Alpha)

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Physical Realm
Physical Laws (Constants) Relativity
Matter Molecule, Atom (Periodic Table), Particle
Force Gravity, Electromagnetism (Light, Color)

Resources

These are organized by a classification scheme developed exclusively for Cosma. More…

General

Portal

CODATA Internationally recommended values of the Fundamental Physical Constants, Atomic and Nuclear (NIST Reference on Constants, Units and Uncertainty)
Radiation, Radioactivity & Radiobiology (Martindale’s Reference Desk)

Dictionary

atom : the smallest particle of an element that can exist either alone or in combination — Webster

OneLook, Free Dictionary, Wiktionary, Urban Dictionary

Thesaurus

Roget’s II (Thesaurus.com), Merriam-Webster Thesaurus, Visuwords

Encyclopedia

Atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small; typical sizes are around 100 picometers (a ten-billionth of a meter, in the short scale).

Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and typically a similar number of neutrons. Protons and neutrons are called nucleons. More than 99.94% of an atom’s mass is in the nucleus. The protons have a positive electric charge, the electrons have a negative electric charge, and the neutrons have no electric charge. If the number of protons and electrons are equal, that atom is electrically neutral. If an atom has more or fewer electrons than protons, then it has an overall negative or positive charge, respectively, and it is called an ion.

The electrons of an atom are attracted to the protons in an atomic nucleus by this electromagnetic force. The protons and neutrons in the nucleus are attracted to each other by a different force, the nuclear force, which is usually stronger than the electromagnetic force repelling the positively charged protons from one another. Under certain circumstances, the repelling electromagnetic force becomes stronger than the nuclear force, and nucleons can be ejected from the nucleus, leaving behind a different element: nuclear decay resulting in nuclear transmutation.

The number of protons in the nucleus defines to what chemical element the atom belongs: for example, all copper atoms contain 29 protons. The number of neutrons defines the isotope of the element. The number of electrons influences the magnetic properties of an atom. Atoms can attach to one or more other atoms by chemical bonds to form chemical compounds such as molecules. The ability of atoms to associate and dissociate is responsible for most of the physical changes observed in nature and is the subject of the discipline of chemistry. — Wikipedia

Atoms (Eric Weisstein’s World of Physics, Wolfram Research)
Encyclopædia Britannica

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Atom (WolframAlpha)
Nuclear Power (Wolfram Alpha)

Science

Atomic Physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus and the processes by which these arrangements change.

The term atomic physics can be associated with nuclear power and nuclear weapons, due to the synonymous use of atomic and nuclear in standard English. Physicists distinguish between atomic physics — which deals with the atom as a system consisting of a nucleus and electrons — and nuclear physics, which considers atomic nuclei alone. — Wikipedia

Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions. Other forms of nuclear matter are also studied. Nuclear physics should not be confused with atomic physics, which studies the atom as a whole, including its electrons. — Wikipedia

Preservation

History





How Can You See an Atom? – Legends of Chemistry (American Chemical Society)

Museum


National Museum of Nuclear Science & History (Albuquerque, New Mexico)

Library

WorldCat, Library of Congress, UPenn Online Books, Open Library

Book

ISBNdb

Education





https://fusedweb.llnl.gov/
Atoms Around Us (Chem4Kids)
Nuclear Physics (Physics4Kids)



Atom in a Box: Real-Time Visualization of the Quantum Mechanical Atomic Orbitals (Dauger Research)

Course



Crash Course Physics (YouTube)

Introduction to Nuclear and Particle Physics (MIT OCW Physics)
Nuclear Science and Engineering (MIT OCW Physics)
OER Commons: Open Educational Resources

Community

Organization

International Atomic Engergy Agency

News

Atomic Physics (AAAS EurekAlert)
Science News, Atom & Cosmos
Scientific American
Phys.Org
NPR Archives

Government

Document

USA.gov

Expression


Humor

Scientist Splits Atom, Finds Toy Prize Inside (Satire Wire)

Hobby

The Man Who Hunts Hidden Radioactive Objects (Chris Baraniuk, BBC Future)

Poem

OEDILF: The Omnificent English Dictionary In Limerick Form

Music

Song Lyrics

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Phys.org - latest science and technology news stories Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine.

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    on February 20, 2019 at 6:00 pm

    A careful re-analysis of data taken at the Department of Energy's Thomas Jefferson National Accelerator Facility has revealed a possible link between correlated protons and neutrons in the nucleus and a 35-year-old mystery. The data have led to the extraction of a universal function that describes the EMC Effect, the once-shocking discovery that quarks inside nuclei have lower average momenta than predicted, and supports an explanation for the effect. The study has been published in the journal […]

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    on February 18, 2019 at 3:53 pm

    Matt Helgeson knew it was time to pull the plug. For weeks, the University of California, Santa Barbara professor of chemical engineering had held out hope that politicians in Washington would find a way to end the government shutdown. If they did, his graduate students could still make their long-planned trip to Maryland to conduct experiments at the National Institute of Standards and Technology's Center for Neutron Research in mid-January. […]

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    on February 18, 2019 at 1:02 pm

    Using neutron characterization techniques a team of scientists have peered inside one of the most unique examples of wire gold, understanding for the first time the specimen's structure and possible formation process. The 263 gram, 12 centimeter tall specimen, known as the Ram's Horn, belongs to the collection of the Mineralogical and Geological Museum Harvard University (MGMH). […]