Induced gamma emission

In physics, induced gamma emission (IGE) refers to the process of fluorescent emission of gamma rays from excited nuclei, usually involving a specific nuclear isomer. It is analogous to conventional fluorescence, which is defined as the emission of a photon (unit of light) by an excited electron in an atom or molecule. In the case of IGE, nuclear isomers can store significant amounts of excitation energy for times long enough for them to serve as nuclear fluorescent materials. There are over 9000 known nuclear isomers but almost all are too intrinsically radioactive to be considered for applications. As of 2006 there were two proposed nuclear isomers that appeared to be physically capable of IGE fluorescence in safe arrangements: tantalum-180m and hafnium-178m2.

History

Induced gamma emission is an example of interdisciplinary research bordering on both nuclear physics and quantum electronics. Viewed as a nuclear reaction it would belong to a class in which only photons were involved in creating and destroying states of nuclear excitation. It is a class usually overlooked in traditional discussions. In 1939 Pontecorvo and Lazard reported the first example of this type of reaction. Indium was the target and in modern terminology describing nuclear reactions it would be written ¹¹⁵In(γ,γ^')^115mIn. The product nuclide carries an "m" to denote that it has a long enough half life (4.5 h in this case) to qualify as being a nuclear isomer. That is what made the experiment possible in 1939 because the researchers had hours to remove the products from the irradiating environment and then to study them in a more appropriate location.

Mystery fiction

Mystery fiction is a genre of fiction usually involving a mysterious death or a crime to be solved. In a closed circle of suspects, each suspect must have a credible motive and a reasonable opportunity for committing the crime. The central character must be a detective who eventually solves the mystery by logical deduction from facts fairly presented to the reader. Sometimes mystery books are nonfictional. "Mystery fiction" can be detective stories in which the emphasis is on the puzzle or suspense element and its logical solution such as a whodunit. Mystery fiction can be contrasted with hardboiled detective stories, which focus on action and gritty realism.

Mystery fiction may involve a supernatural mystery where the solution does not have to be logical, and even no crime involved. This usage was common in the pulp magazines of the 1930s and 1940s, where titles such as Dime Mystery, Thrilling Mystery and Spicy Mystery offered what at the time were described as "weird menace" stories—supernatural horror in the vein of Grand Guignol. This contrasted with parallel titles of the same names which contained conventional hardboiled crime fiction. The first use of "mystery" in this sense was by Dime Mystery, which started out as an ordinary crime fiction magazine but switched to "weird menace" during the latter part of 1933.

Texture mapping

Texture mapping is a method for adding detail, surface texture (a bitmap or raster image), or color to a computer-generated graphic or 3D model. Its application to 3D graphics was pioneered by Edwin Catmull in 1974.

Originally a method that simply wrapped and mapped pixels from a texture to a 3D surface - now more technically called diffuse mapping to distinguish it from more complex mappings - in recent decades the advent of multi-pass rendering and complex mapping such as height mapping, bump mapping, normal mapping, displacement mapping, reflection mapping, mipmaps, occlusion mapping, and many other complex variations on the technique have made it possible to simulate near-photorealism in real time, by vastly reducing the number of polygons and lighting calculations needed to construct a realistic and functional 3D scene.

With Me

With Me may refer to: