Nucleate boiling

Nuclear powered cruisers of the United States Navy

President Adly Mansour announced on 7 November 2013 that Egypt was restarting its nuclear power program in El Dabaa; a deal was reached with the residents in which it was agreed that a residential area will also be built. The Egyptian minister of electricity, Ahmed Emam, has called the project "necessary" because of a small amount of renewable energy sources and not enough fuel.

Nuclear weapons

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Nuclearia
Nuclearia thermophila

Nuclear power phase-out

Nucleic acid quantitation

In nuclear physics and nuclear chemistry, a nuclear reaction is semantically considered to be the process in which two nuclei, or else a nucleus of an atom and a subatomic particle (such as a proton, neutron, or high energy electron) from outside the atom, collide to produce one or more nuclides that are different from the nuclide(s) that began the process. Thus, a nuclear reaction must cause a transformation of at least one nuclide to another. If a nucleus interacts with another nucleus or particle and they then separate without changing the nature of any nuclide, the process is simply referred to as a type of nuclear scattering, rather than a nuclear reaction.In principle, a reaction can involve more than two particles colliding, but because the probability of three or more nuclei to meet at the same time at the same place is much less than for two nuclei, such an event is exceptionally rare (see triple alpha process for an example very close to a three-body nuclear reaction). "Nuclear reaction" is a term implying an induced change in a nuclide, and thus it does not apply to any type of radioactive decay (which by definition is a spontaneous process).Natural nuclear reactions occur in the interaction between cosmic rays and matter, and nuclear reactions can be employed artificially to obtain nuclear energy, at an adjustable rate, on demand. Perhaps the most notable nuclear reactions are the nuclear chain reactions in fissionable materials that produce induced nuclear fission, and the various nuclear fusion reactions of light elements that power the energy production of the Sun and stars.Nuclear reactions may be shown in a form similar to chemical equations, for which invariant mass must balance for each side of the equation, and in which transformations of particles must follow certain conservation laws, such as conservation of charge and baryon number (total atomic mass number). An example of this notation follows:To balance the equation above for mass, charge and mass number, the second nucleus to the right must have atomic number 2 and mass number 4; it is therefore also helium-4. The complete equation therefore reads:or more simply:Instead of using the full equations in the style above, in many situations a compact notation is used to describe nuclear reactions. This style of the form A(b,c)D is equivalent to A + b producing c + D. Common light particles are often abbreviated in this shorthand, typically p for proton, n for neutron, d for deuteron, α representing an alpha particle or helium-4, β for beta particle or electron, γ for gamma photon, etc. The reaction above would be written as Li-6(d,α)α.

Nucleate boiling is a type of boiling that takes place when the surface temperature is hotter than the saturated fluid temperature by a certain amount but where the heat flux is below the critical heat flux. For water, as shown in the graph below, nucleate boiling occurs when the surface temperature is higher than the saturation temperature (TS) by between 10 °C (18 °F) to 30 °C (54 °F). The critical heat flux is the peak on the curve between nucleate boiling and transition boiling.

Nuclear structure

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A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or from a combination of fission and fusion reactions (thermonuclear bomb). Both bomb types release large quantities of energy from relatively small amounts of matter. The first test of a fission ("atomic") bomb released an amount of energy approximately equal to 20,000 tons of TNT (84 TJ).

Cienkowsky, 1865

Nuclear reprocessing plant Wackersdorf

A nuclear power phase-out is the discontinuation of usage of nuclear power for energy production. Often initiated because of concerns about nuclear power, phase-outs usually include shutting down nuclear power plants and looking towards fossil fuels and renewable energy.Three nuclear accidents have influenced the discontinuation of nuclear power: the 1979 Three Mile Island partial nuclear meltdown in the United States, the 1986 Chernobyl disaster in the USSR, and the 2011 Fukushima nuclear disaster in Japan.Following the March 2011 Fukushima nuclear disaster, Germany has permanently shut down eight of its 17 reactors and pledged to close the rest by the end of 2022. Italy voted overwhelmingly to keep their country non-nuclear. Switzerland and Spain have banned the construction of new reactors. Japan’s prime minister has called for a dramatic reduction in Japan’s reliance on nuclear power. Taiwan’s president did the same. Shinzō Abe, the new prime minister of Japan since December 2012, announced a plan to re-start some of the 54 Japanese nuclear power plants (NPPs) and to continue some NPP sites under construction.As of 2016, countries including Australia, Austria, Denmark, Greece, Ireland, Italy, Latvia, Liechtenstein, Luxembourg, Malaysia, Malta, New Zealand, Norway, Philippines, and Portugal have no nuclear power stations and remain opposed to nuclear power. Belgium, Germany, Spain and Switzerland are phasing-out nuclear power. Globally, more nuclear power reactors have closed than opened in recent years but overall capacity has increased.Italy is the only country that has closed all of functioning nuclear plants. Lithuania, Kazakhstan have shut down their only nuclear plants, but plan to built new ones to replace them. Armenia shut down its only nuclear plant but subsequently restarted it. Austria never used its first nuclear plant that was completely built. Due to financial, politic and technical reasons Cuba, Libya, North Korea and Poland never completed the construction of their first nuclear plants (although North Korea and Poland plan to). Azerbaijan, Georgia, Ghana, Ireland, Kuwait, Oman, Peru, Singapore, Venezuela have planned, but not constructed their first nuclear plants. Between 2005 and 2015 the global production of nuclear power declined by 0.7%.

Nucleic acid analogues are compounds which are analogous (structurally similar) to naturally occurring RNA and DNA, used in medicine and in molecular biology research. Nucleic acids are chains of nucleotides, which are composed of three parts: a phosphate backbone, a pentose sugar, either ribose or deoxyribose, and one of four nucleobases. An analogue may have any of these altered.

Nuclear weapon yield

In molecular biology, quantitation of nucleic acids is commonly performed to determine the average concentrations of DNA or RNA present in a mixture, as well as their purity. Reactions that use nucleic acids often require particular amounts and purity for optimum performance. To date, there are two main approaches used by scientists to quantitate, or establish the concentration, of nucleic acids (such as DNA or RNA) in a solution. These are spectrophotometric quantification and UV fluorescence tagging in presence of a DNA dye.

Nuclear regulatory commission region IV

Nuclear reactors

The Nuclear reprocessing plant Wackersdorf (German: Wiederaufbereitungsanlage, abbreviated WAA) is a reprocessing plant in Wackersdorf in Bavaria, Germany. Because of protests the plant was never completed. Today it is an industrial site with no special features.

Saudi Arabia is not known to have a nuclear weapons program. From an official and public standpoint, Saudi Arabia has been an opponent of nuclear weapons in the Middle East, having signed the Treaty on the Non-Proliferation of Nuclear Weapons, and is a member of the coalition of countries demanding a Nuclear-weapon-free zone in the Middle East. Studies of nuclear proliferation have not identified Saudi Arabia as a country of concern.However, over the years there have been media reports of Saudi Arabia's intent to purchase a nuclear weapon from an outside source. In 2003, a leaked strategy paper laid out three possible options for the Saudi government: to acquire a nuclear deterrent, to ally with and become protected by an existing nuclear nation, or to try to reach agreement on having a nuclear-free Middle East. UN officials and weapon specialists have suggested this review was prompted by a distancing of relations with the US, concerns over Iran's nuclear program, and the lack of international pressure on Israel to give up its nuclear weapons.

The explosive yield of a nuclear weapon is the amount of energy released when that particular nuclear weapon is detonated, usually expressed as a TNT equivalent (the standardized equivalent mass of trinitrotoluene which, if detonated, would produce the same energy discharge), either in kilotons (kt—thousands of tons of TNT), in megatons (Mt—millions of tons of TNT), or sometimes in terajoules (TJ). An explosive yield of one terajoule is 0.239 kt of TNT.

Nucleate boiling is a type of boiling that takes place when the surface temperature is hotter than the saturated fluid temperature by a certain amount but where the heat flux is below the critical heat flux. For water, as shown in the graph below, nucleate boiling occurs when the surface temperature is higher than the saturation temperature (TS) by between 10 °C (18 °F) to 30 °C (54 °F). The critical heat flux is the peak on the curve between nucleate boiling and transition boiling. The heat transfer from surface to liquid is greater than that in film boiling.

Nucleic acid analogues are compounds which are analogous (structurally similar) to naturally occurring RNA and DNA, used in medicine and in molecular biology research. Nucleic acids are chains of nucleotides, which are composed of three parts: a phosphate backbone, a pentose sugar, either ribose or deoxyribose, and one of four nucleobases. An analogue may have any of these altered. Typically the analogue nucleobases confer, among other things, different base pairing and base stacking properties. Examples include universal bases, which can pair with all four canonical bases, and phosphate-sugar backbone analogues such as PNA, which affect the properties of the chain (PNA can even form a triple helix). Nucleic acid analogues are also called Xeno Nucleic Acid and represent one of the main pillars of xenobiology, the design of new-to-nature forms of life based on alternative biochemistries.Artificial nucleic acids include peptide nucleic acid (PNA), Morpholino and locked nucleic acid (LNA), as well as glycol nucleic acid (GNA) and threose nucleic acid (TNA). Each of these is distinguished from naturally occurring DNA or RNA by changes to the backbone of the molecule.In May 2014, researchers announced that they had successfully introduced two new artificial nucleotides into bacterial DNA, and by including individual artificial nucleotides in the culture media, were able to passage the bacteria 24 times; they did not create mRNA or proteins able to use the artificial nucleotides. The artificial nucleotides featured 2 fused aromatic rings.

Nuclear weapon

Nuclear reaction

Understanding the structure of the atomic nucleus is one of the central challenges in nuclear physics.

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Saudi Arabia is not known to have a nuclear weapons program. From an official and public standpoint, Saudi Arabia has been an opponent of nuclear weapons in the Middle East, having signed the Treaty on the Non-Proliferation of Nuclear Weapons, and is a member of the coalition of countries demanding a Nuclear-weapon-free zone in the Middle East.

The United States Navy at one time had nuclear powered cruisers as part of its fleet. The first such ship was USS Long Beach (CGN-9). Commissioned in late summer 1961, she was the world's first nuclear powered surface combatant. She was followed a year later by USS Bainbridge (DLGN-25).

A nuclear power phase-out is the discontinuation of usage of nuclear power for energy production.

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A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or from a combination of fission and fusion reactions (thermonuclear bomb). Both bomb types release large quantities of energy from relatively small amounts of matter. The first test of a fission ("atomic") bomb released an amount of energy approximately equal to 20,000 tons of TNT (84 TJ). The first thermonuclear ("hydrogen") bomb test released energy approximately equal to 10 million tons of TNT (42 PJ). A thermonuclear weapon weighing little more than 2,400 pounds (1,100 kg) can release energy equal to more than 1.2 million tons of TNT (5.0 PJ). A nuclear device no larger than traditional bombs can devastate an entire city by blast, fire, and radiation. Since they are weapons of mass destruction, the proliferation of nuclear weapons is a focus of international relations policy.Nuclear weapons have been used twice in war, both times by the United States against Japan near the end of World War II. On August 6, 1945, the U.S. Army Air Forces detonated a uranium gun-type fission bomb nicknamed "Little Boy" over the Japanese city of Hiroshima; three days later, on August 9, the U.S. Army Air Forces detonated a plutonium implosion-type fission bomb nicknamed "Fat Man" over the Japanese city of Nagasaki. These bombings resulted in the deaths of approximately 200,000 civilians and military personnel from injuries sustained from the explosions. The ethics of these bombings and their role in Japan's surrender are subjects of debate.Since the atomic bombings of Hiroshima and Nagasaki, nuclear weapons have been detonated over two thousand times for testing and demonstration. Only a few nations possess such weapons or are suspected of seeking them. The only countries known to have detonated nuclear weapons—and acknowledge possessing them—are (chronologically by date of first test) the United States, the Soviet Union (succeeded as a nuclear power by Russia), the United Kingdom, France, China, India, Pakistan, and North Korea. Israel is believed to possess nuclear weapons, though, in a policy of deliberate ambiguity, it does not acknowledge having them. Germany, Italy, Turkey, Belgium and the Netherlands are nuclear weapons sharing states. South Africa is the only country to have independently developed and then renounced and dismantled its nuclear weapons.The Treaty on the Non-Proliferation of Nuclear Weapons aims to reduce the spread of nuclear weapons, but its effectiveness has been questioned, and political tensions remained high in the 1970s and 1980s. Modernisation of weapons continues to this day.

Nuclear program of Egypt

OceanDots.com: Bikini Atoll

Nucleic acid analogue

Nuclear testing at Bikini Atoll

In molecular biology, quantitation of nucleic acids is commonly performed to determine the average concentrations of DNA or RNA present in a mixture, as well as their purity. Reactions that use nucleic acids often require particular amounts and purity for optimum performance. To date, there are two main approaches used by scientists to quantitate, or establish the concentration, of nucleic acids (such as DNA or RNA) in a solution.

In nuclear physics and nuclear chemistry, a nuclear reaction is semantically considered to be the process in which two nuclei, or else a nucleus of an atom and a subatomic particle (such as a proton, neutron, or high energy electron) from outside the atom, collide to produce one or more nuclides that are different from the nuclide(s) that began the process. Thus, a nuclear reaction must cause a transformation of at least one nuclide to another.

Nuclear weapons abolition

Nuclear regulatory commission region iv

Nuclear program of Saudi Arabia