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The Crack Movement, or literature of the Crack generation (Spanish: la generación del "crack"), describes a literary movement in Mexico that began in the mid-1990s.
La Generación del crack (o Crack) es un movimiento literario mexicano de fines del siglo XX, en ruptura con el llamado postboom latinoamericano. Está integrado por Ignacio Padilla , Jorge Volpi , Eloy Urroz , Pedro Ángel Palou , Ricardo Chávez Castañeda y Vicente Herrasti .
- Motivation
- Linear Elastic Fracture Mechanics
- Elastic–plastic Fracture Mechanics
- See Also
- Further Reading
- External Links
The processes of material manufacture, processing, machining, and forming may introduce flaws in a finished mechanical component. Arising from the manufacturing process, interior and surface flaws are found in all metal structures. Not all such flaws are unstable under service conditions. Fracture mechanics is the analysis of flaws to discover thos...
Griffith's criterion
Fracture mechanics was developed during World War I by English aeronautical engineer A. A. Griffith – thus the term Griffith crack – to explain the failure of brittle materials.Griffith's work was motivated by two contradictory facts: 1. The stress needed to fracture bulk glassis around 100 MPa (15,000 psi). 2. The theoretical stress needed for breaking atomic bonds of glass is approximately 10,000 MPa (1,500,000 psi). A theory was needed to reconcile these conflicting observations. Also, exp...
Irwin's modification
Griffith's theory provides excellent agreement with experimental data for brittle materials such as glass. For ductile materials such as steel, although the relation σ f a = C {\displaystyle \sigma _{f}{\sqrt {a}}=C} still holds, the surface energy (γ) predicted by Griffith's theory is usually unrealistically high. A group working under G. R. Irwin at the U.S. Naval Research Laboratory(NRL) during World War II realized that plasticity must play a significant role in the fracture of ductile ma...
Stress intensity factor
Another significant achievement of Irwin and his colleagues was to find a method of calculating the amount of energy available for fracture in terms of the asymptotic stress and displacement fields around a crack front in a linear elastic solid. This asymptotic expression for the stress field in mode I loading is related to the stress intensity factor K I {\displaystyle K_{I}} following: 1. σ i j = ( K I 2 π r ) f i j ( θ ) {\displaystyle \sigma _{ij}=\left({\cfrac {K_{I}}{\sqrt {2\pi r}}}\ri...
Most engineering materials show some nonlinear elastic and inelastic behavior under operating conditions that involve large loads.[citation needed]In such materials the assumptions of linear elastic fracture mechanics may not hold, that is, 1. the plastic zone at a crack tip may have a size of the same order of magnitude as the crack size 2. the si...
Buckley, C.P. "Material Failure", Lecture Notes (2005), University of Oxford.Davidge, R.W., Mechanical Behavior of Ceramics, Cambridge Solid State Science Series, (1979)Demaid, Adrian, Fail Safe, Open University (2004)Green, D., An Introduction to the Mechanical Properties of Ceramics, Cambridge Solid State Science Series, Eds. Clarke, D.R., Suresh, S., Ward, I.M. (1998)La Generación del crack (o Crack) es un movimiento literario mexicano de fines del siglo XX, en ruptura con el llamado postboom latinoamericano. Está integrado por Ignacio Padilla , Jorge Volpi , Eloy Urroz , Pedro Angel Palou, Ricardo Chávez Castañeda y Vicente Herrasti.
7 de oct. de 2017 · The Crack movement began under the premise of seeking “an aesthetic risk, a formal risk, the one which implies the desire of a genre renovation” at “the end of a truncated century in time and place, shattered by an excess of bindings” (Chávez et al. 217).
CIA involvement in Contra cocaine trafficking. A number of writers have alleged that the United States Central Intelligence Agency (CIA) was involved in the Nicaraguan Contras ' cocaine trafficking operations during the 1980s Nicaraguan civil war. These claims have led to investigations by the United States government, including ...
Enfrentados con la caída de los precios de su producto ilegal, los traficantes convirtieron el polvo en “crack”, una forma sólida de cocaína que se podía fumar. Fragmentada en pequeños pedazos, o “rocas”, esta forma de cocaína se podía vender en pequeñas cantidades, para más personas y con ganancias mayores.
