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Sample records for ablacion laser posibilidades

  1. Thin film growing by the laser ablation technique: possibilities for growing of dosimetric materials; Crecimiento de capas delgadas por la tecnica de ablacion laser: posibilidades para crecimiento de materiales dosimetricos

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    Rojas R, E.M.; Melo M, M.; Enriquez Z, E.; Fernandez G, M.; Haro P, E.; Hernandez P, J.L. [UAM-I, Laboratorio de Optica Cuantica, 09340 Mexico D.F. (Mexico)

    2005-07-01

    In this talk we will present the basics about the laser ablation technique and how it is used for thin film growing, either as a single film or a stack of thin films, as well as some methods to characterize in real time the film thickness. Finally, we will discuss the possibilities of using laser ablation for growing thin films with applications to dosimetry. (Author)

  2. Obtention of high hardness multilayer systems by laser ablation; Obtencion de sistemas multicapa de alta dureza por ablacion laser

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    Mejia T, I.S

    2007-07-01

    In this thesis work the synthesis of thin films of titanium nitride (TiN), amorphous carbon nitride (CN{sub x}) amorphous carbon (a-C) and Ti/TiN/CNx multilayers and Ti/TiN/a-C by means of the laser ablation technique, with the objective of obtaining films of high hardness is studied, as well as to produce multilayer coatings with superior properties to the individual layers. The effect that has the laser fluence used for ablationing the targets in the structure and mechanical properties of the films deposited of TiN was investigated. It was found that the hardness is increased in lineal way approximately with the fluence increment up to 19 J/cm{sup 2}. Thin films of a-C with hardness of the order of 12 GPa. likewise CN{sub x} films with high hardness (18.4 GPa) were obtained. The hardness of the deposited films was analyzed and it was related with its microstructure and deposit conditions. It was concluded that the Ti/TiN/CNx and Ti/TiN/a-C systems presented bigger hardness that of its individual components. (Author)

  3. Design of a chamber for deposit of thin films by laser ablation; Diseno de una camara para el deposito de peliculas delgadas por ablacion laser

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    Chirino O, S

    2001-07-01

    The present work has as purpose to design a vacuum chamber, to the one that is denominated chamber of ablation, in which were carried out deposits of thin films using the well-known technique as laser ablation. To fulfill the purpose, the work has been distributed in the following way: in the chapter 1 there are discussed the generalities of the technique of ablation laser for the obtaining of materials in form of thin film, in the chapter 2 the basic concepts of the vacuum technology are mentioned that includes among other things, systems to produce vacuum and vacuum gages and in the chapter 3 the design of the chamber is presented with the accessories and specific systems. (Author)

  4. Structural characterization of thin films of titanium nitride deposited by laser ablation; Caracterizacion estructural de peliculas delgadas de nitruro de titanio depositadas por ablacion laser

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    Castro C, M.A.; Escobar A, L.; Camps C, E.; Mejia H, J.A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

    Thin films of titanium nitride were deposited using the technique of laser ablation. It was studied the effect of the density of laser energy used for ablation the target as well as of the pressure of the work gas about the structure and the hardness of the deposited thin films. Depending on the pressure of the work gas films was obtained with preferential orientation in the directions (200) and (111). At a pressure of 1 x 10{sup -2} Torr only the direction (200) was observed. On the other hand to the pressure of 5 x 10{sup -3} Torr the deposited material this formed by a mixture of the orientation (200) and (111), being the direction (111) the predominant one. Thin films of Ti N were obtained with hardness of up to 24.0 GPa that makes to these attractive materials for mechanical applications. The hardness showed an approximately linear dependence with the energy density. (Author)

  5. Synthesis and characterization of nanoparticles of nickel obtained by laser ablation; Sintesis y caracterizacion de nanoparticulas de niquel obtenidas por ablacion laser

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    Aviles, R.; Escobar A, L.; Camps, E.; Santiago, P. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Ascencio, J.A.; Von, H. [Instituto Mexicano del Petroleo, Mexico D.F. (Mexico)

    2002-07-01

    The result of the formation of nickel nanoparticles by the laser ablation technique with a size less or equal to 1.3 nm is reported, also the formation of agglomerates of tens of nanometers is shown. Under the experimental conditions used a high particle density (around 10{sup 5} particles/{mu}m{sup 2}) is obtained. The stability of the particles in function of its atom quantity, for less or equal sizes to 2 nm is studied, finding that the most stable structure is the icosahedron. (Author)

  6. Deposit of thin films of nitrided amorphous carbon using the laser ablation technique; Deposito de peliculas delgadas de carbono amorfo nitrurado utilizando la tecnica de ablacion laser

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    Rebollo, P.B.; Escobar A, L.; Camps C, E. [Departamento de Fisica, Instituto Nacional de Investigaciones Nucleares, C.P. 52045 Salazar, Estado de Mexico (Mexico); Haro P, E.; Camacho L, M.A. [Departamento de Fisica, Universidad Autonoma Metropolitana Iztapalapa (Mexico); Muhl S, S. [Instituto de Investigacion en Materiales, UNAM (Mexico)

    2000-07-01

    It is reported the synthesis and characterization of thin films of amorphous carbon (a-C) nitrided, deposited by laser ablation in a nitrogen atmosphere at pressures which are from 4.5 x 10 {sup -4} Torr until 7.5 x 10 {sup -2} Torr. The structural properties of the films are studied by Raman spectroscopy obtaining similar spectra at the reported for carbon films type diamond. The study of behavior of the energy gap and the ratio nitrogen/carbon (N/C) in the films, shows that the energy gap is reduced when the nitrogen incorporation is increased. It is showed that the refraction index of the thin films diminish as nitrogen pressure is increased, indicating the formation of graphitic material. (Author)

  7. Synthesis and characterization of thin films of nitrided amorphous carbon deposited by laser ablation; Sintesis y caracterizacion de peliculas delgadas de carbono amorfo nitrurado, depositadas por ablacion laser

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    Rebollo P, B

    2001-07-01

    The objective of this work is the synthesis and characterization of thin films of amorphous carbon (a-C) and thin films of nitrided amorphous carbon (a-C-N) using the laser ablation technique for their deposit. For this purpose, the physical properties of the obtained films were studied as function of diverse parameters of deposit such as: nitrogen pressure, power density, substrate temperature and substrate-target distance. For the characterization of the properties of the deposited thin films the following techniques were used: a) Raman spectroscopy which has demonstrated being a sensitive technique to the sp{sup 2} and sp{sup 3} bonds content, b) Energy Dispersive Spectroscopy which allows to know semi-quantitatively way the presence of the elements which make up the deposited films, c) Spectrophotometry, for obtaining the absorption spectra and subsequently the optical energy gap of the deposited material, d) Ellipsometry for determining the refraction index, e) Scanning Electron Microscopy for studying the surface morphology of thin films and, f) Profilemetry, which allows the determination the thickness of the deposited thin films. (Author)

  8. Deposit of thin films of TiN, a-C, Ti/TiN/a-C by laser ablation; Deposito de peliculas delgadas de TiN, a-C, Ti/TiN/a-C por ablacion laser

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    Mejia, I.S.; Escobar A, L.; Camps, E.; Romero, S. [ININ, 52045 Ocoyoacac, Estado de mexico (Mexico); Muhl, S. [IIM, UNAM, A.P. 364, 01000 Mexico D.F. (Mexico)

    2006-07-01

    Thin films of titanium nitride (TiN), amorphous carbon (a-C), as well as bilayers of Ti/TiN/a-C were deposited by means of the laser ablation technique. It was investigated the effect that it has the laser fluence used to ablation the targets in the structure and mechanical properties of the TiN deposited films. The TiN obtained films have a preferential orientation in the direction (200). The results show that the hardness of this material is influenced by the laser fluence. It is observed that the hardness is increased in an approximately lineal way with the increment of the fluence up to 19 J/cm{sup 2}. The films of amorphous carbon present hardness of the order of 11.2 GPa. Likewise it was found that the multilayers of Ti/TiN/aC presented a bigger hardness that of its individual components. (Author)

  9. Design and fabrication of a chamber for the deposit of thin films by laser ablation; Diseno y fabricacion de una camara para el deposito de peliculas delgadas por ablacion laser

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    Chirino O, S.; Escobar A, I.; Camps C, E.; Garcia E, J.I. [Departamento de Fisica, ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The laser ablation technique is an alternative for the obtention of thin films which is less expensive, more reliable, efficient and with some advantages with respect to conventional processes. On of the most important components which forms a laser ablation system is the vacuum chamber, that has as general purposes the following: a) To carry out studies about plasma such as optical emission spectroscopy and measurements by deflectometry. b) To carry out an In situ monitoring about the film growth through the reflectivity measurements of the combination substrate-film. c) To deposit thin films of different materials such as oxides, carbon, metals, etc. In this work it is showed how the vacuum chamber was designed and made to perform the store of thin films by laser ablation and for characterising the formed plasma as a result of the ablation process. The chamber design was enough versatile that will allow to add it more accessory just making it simple modifications. Its cost was very cheap more or less one twentieth of a commercial chamber. (Author)

  10. Thin films deposited by laser ablation for the measurement of the ionizing and non-ionizing radiation; Peliculas delgadas depositadas por ablacion laser para la medicion de radiacion ionizante y no ionizante

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    Villarreal B, J.E.; Escobar A, L.; Camps, E.; Romero, S.; Gonzalez, P.; Salinas, B. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2001-07-01

    In this work the obtained results to synthesize thin films of amorphous carbon with incorporated nitrogen and hydrogen are presented, as well as thin films of aluminium oxide using the laser ablation technique. The thin films were exposed to ionizing radiation (gamma rays of a {sup 60} Co source, beta radiation of a {sup 90} Sr source) and a non-ionizing radiation (UV radiation). The obtained results show that it is possible to obtain materials in thin film form with thickness of hundreds of nanometers, which present thermoluminescent response when being irradiated with ionizing radiation and non-ionizing radiation. (Author)

  11. Characterization by FTIR and nuclear analytical techniques of CN{sub x} films elaborated by laser ablation; Caracterizacion por FTIR y tecnicas analiticas nucleares de peliculas de CN{sub x} elaboradas por ablacion laser

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    Olea M, O.F

    2003-07-01

    At the present time the technique of deposit of laser ablation is used to produce different types of thin films. At the moment in the National Institute of Nuclear Research (ININ) it is carried out an investigation on the thermoluminescent response of thin films of CN{sub x} with possible application in dosimetry of electromagnetic radiation. Under this context, the present work is part of this investigation and has as objective to characterize thin films of CN{sub x} by means of Infrared spectrometry and nuclear analytical techniques. The deposits were elaborated by laser ablation under different such experimental conditions as: pressure of Nitrogen in the system (3 x 10{sup -3} and 7.5 X 10{sup -2} Torr), Distance target-substrate (3 and 5 cm) and density of incident energy in the target (from 17.5 up to 23.8 J/cm{sup 2}). Graphite of high purity was used like target and the deposits were made on their substrates of intrinsic silicon (100). By means of infrared spectrometry by Fourier Transform (Ftir) the type of bonds which are in the structure of the films of CN{sub x} were determined. The spectra of this type of samples present in general four characteristic bands related with different types of bonds among the elements C, O, H, N such as: C-C, C-N, C-H, N-H, O-H, C=N, C{identical_to}N, among others. It was carried out a semi quantitative study of the samples isolating each band of the total infrared spectra and making a comparison between their intensities and forms. This study allowed to observe that there is a dependence of the structure of the films with regard to the time, since mainly bonds of the type Sp{sup 3} between Hydrogen and Carbon (C-H) they presented a remarkable variation in intensity, increasing as it lapsed the time until reaching to a stabilization where the bonds already not varying. This increase probably is due to the absorption of water of the atmosphere, although one has seen in the literature that the incorporation of this compound in

  12. LA POSIBILIDAD ABSOLUTA

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    Juan Antonio Gómez

    1985-04-01

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    Los más eruditos y prestigiosos expositores nacionales han competido en destacar aspectos de la obra de López de Mesa con ocasión del centenario de su nacimiento, y las universidades y academias que él señoreó cerca de medio siglo con su erudición polifacética están revisando los variados aspectos de su personalidad. Sin embargo, nos parece que entre tantos elogios y oraciones panegíricas ha faltado dar un mayor énfasis a las líneas directrices de su posición filosófica que el profesor, y presidente que fue de la Academia Nacional de Medicina, dejó entrever en todas las ocasiones en que habló o escribió. Infortunadamente los conceptos estaban tan envueltos en su prosa barroca que muchos de sus admiradores quedáronse en la forma sin penetrar al fondo doctrinal.
    En cierta forma López de Mesa erró al presentar sus pensamientos abstractos ante públicos heterogéneos que respondieron al estilo de los elocuentes discursos o conferencias en que habló al país pero no recogieron la enseñanza: al profesor le faltó una escuela de su pensamiento. En realidad este puede sumarse fundamentalmente en dos ideas generatrices que guiaron toda su vida y alrededor de las cuales elaboró disquisiciones eruditas sobre casi todos los aspectos de la cultura. Podría decirse que escudriñó tales temas para ejemplarizar su concepción general del universo y no con el propósito de contribuir a ellos por sí mismos.

    Las dos ideas generatrices a que aludimos antes son: 1 la posibilidad absoluta y 2 la estética del comportamiento, que es solamente la praxis de las ideas derivadas de la primera concepción. Con el objeto de fundamentar la doctrina de la posibilidad y presentar pruebas de ella estudió historia, para citar ejemplos de la segunda hizo biografías, para unir procesos mentales con teorías neurofisiológicas estudió gramática, para aplicar en la nación sus ideas trajinó en política. Imposible abarcar en corto espacio

  13. El teorema de posibilidad

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    Giner, Salvador

    2010-04-01

    Full Text Available The sociological explanation of altruistic behaviour often encounters serious difficulties. This essay attempts to solve the altruism enigma through the presentation of an alternative explanation to Arrow’s Possibility Theorem as well as to Berlin’s serious objections to rational calculus in political behaviour. Bestowing charisma and/or sacredness to certain values often proves the solution to the puzzle by providing a rational criterion for action which cancels out other criteria and calculations. The Possibility Theorem which is put forward here solves the problem of the rationality of the supposedly irrational in rational choice situations and dilemmas. The Possibility Theorem is a contribution to the issue of the rationality of charisma and, therefore, to the analytical explanation of altruistic behaviour.

    La explicación sociológica del altruismo presenta serias dificultades. El presente ensayo propone resolver el enigma del altruismo mediante la presentación de una explicación alternativa al Teorema de Imposibilidad de Arrow así como a las objeciones de Berlin al cálculo racional en política. La atribución de carisma o sacralidad a ciertos valores genera, frecuentemente, la solución. Tal atribución suministra un criterio racional de acción que supera y descarta otros cálculos. El Teorema de Posibilidad que aquí se postula resuelve el problema de la racionalidad de lo supuestamente irrracional en las trías o elecciones racionales de conducta. El Teorema propuesto es una aportación a la cuestión de la racionalidad del carisma y, por ende, a la explicación analítica del altruismo.

  14. Effect of the ions energy in the physical properties of thin films of CN{sub x} deposited by laser ablation; Efecto de la energia de los iones en las propiedades fisicas de peliculas delgadas de CN{sub x} depositadas por ablacion laser

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    Arrieta C, A.; Escobar A, L.; Camps C, E.; Romero H, S.; Mejia H, J.A.; Gonzalez, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Camacho L, M.A. [UAEM, 50000 Toluca, Estado de Mexico (Mexico)

    2004-07-01

    Thin films of carbon nitride were deposited using the laser ablation technique starting from a carbon target in atmosphere of N{sub 2}, varying the fluence of the laser and maintaining fixed the distance target-substrate. It was diagnosed the formed plasma, being determined the average kinetic energy of the ions present in the plasma, as well as their density. The characterization of the deposited films includes composition, optical gap, chemical structure and microstructure. They were related the properties of the layers with the plasma parameters with the purpose of clarifying that paper plays in the growth of the layer. Additionally it was studied their thermoluminescent response to being excited with UV radiation. (Author)

  15. Co{sub 3}O{sub 4}/TiO{sub 2} films obtained by laser ablation and sol-gel for the reaction of oxygen liberation in alkaline medium; Peliculas de Co{sub 3}O{sub 4}/TiO{sub 2} obtenidas por ablacion laser y sol-gel para la reaccion de desprendimiento de oxigeno en medio alcalino

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    Perez A, J.; Fernandez V, S. M.; Escobar A, L.; Jimenez B, J. [Departamento de Quimica, ININ, Carretera Mexico-Toluca s/n, Ocoyoacac, Estado de Mexico (Mexico)

    2008-07-01

    The laser ablation technique known as Pulsed Laser Deposition (PLD) is used for obtaining thin films of TiO{sub 2}/SnO{sub 2}, which was later modified with Co{sub 3}O{sub 4} by PLD or by sol-gel technique. The films were characterized by X-ray diffraction, ultraviolet Vis and Raman spectroscopies, scanning electron microscopy and energy analysis of the dispersed X-rays produced by Auger decay. The anatase phase with particles of nano metric size was obtained by depositing the titanium dioxide in argon atmosphere. The Co{sub 3}O{sub 4} films obtained by PLD on the TiO{sub 2} showed the same morphology. The electrocatalytic activity of the films that were used as photo anodes for the reaction of oxygen liberation was carried out in the darkness, with environment light and the light emitted by a xenon lamp. The current density was higher for films of Co{sub 3}O{sub 4}/TiO{sub 2}/SnO{sub 2} obtained by PLD that for cobalt dioxide of mixed valence obtained by sol-gel. (Author)

  16. TiO{sub 2} obtained by laser ablation and it response in alkaline medium for the oxygen detachment reaction; TiO{sub 2} obtenido por ablacion laser y su respuesta en medio alcalino para la reaccion de desprendimiento de oxigeno

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    Jimenez B, J.; Escobar A, L.; Fernandez V, S.M. [ININ, 52750 La Marquesa, Ocoyoacac (Mexico)]. e-mail: jjb@nuclear.inin.mx

    2007-07-01

    The performance of the photo electrocatalysts materials depends on one hand of the it structures of the crystalline lattice and of their surface properties, those which in turn are determined by the material preparation method. In this work the laser ablation technique to obtain thin films of titanium dioxide on recovered glass with tin oxide is presented. The carried out analyses showed homogeneous films, one of amorphous titanium oxide with a band width of 3.43 eV and the other one with anatase structure with a band energy of 3.41 eV. The photoresponse for the oxygen detachment it was better for the anatase. In a 0.1M KOH medium it was found corrosion in the films. (Author)

  17. Thermoluminescence of thin films deposited by laser ablation; Termoluminiscencia de peliculas delgadas depositadas por ablacion laser

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    Escobar A, L.; Camps, E.; Arrieta, A.; Romero, S.; Gonzalez, P.R.; Olea M, O.; Diaz E, R. [Depto. de Fisica, ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2003-07-01

    Materials in thin film form have received great attention in the last few years mainly because of their singular properties, which may differ significantly from their bulk attributes making them attractive for a wide variety of applications. In particular, thermoluminescence (Tl) properties of thin films have been studied recently owing to their potential applications in detection for both ionizing and non ionizing radiation. The aim of the present work is to report the synthesis and characterization of C Nx, aluminum oxide and titanium oxide thin films. Thermoluminescence response of the obtained thin films was studied after subject thin films to UV radiation (254 nm) as well as to gamma radiation (Co-60). Thermoluminescence glow curves exhibited a peak centered at 150 C for CN{sub x} whereas for titanium oxide the glow curve shows a maximum peaking at 171 C. Characterization of the physical properties of the deposited materials is presented. (Author)

  18. Wolbachia, una pandemia con posibilidades

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    Marcela S. RODRIGUERO

    2013-01-01

    Full Text Available La infección causada por Wolbachia es la más extendida entre los animales. La capacidad de esta bacteria para manipular la reproducción de sus hospedadores la posicionan en el centro de la biología de los organismos, influyendo en procesos tan capitales como la determinación del sexo, el ciclo celular, la formación y extinción de especies y el comportamiento de artrópodos entre los que se cuentan varias plagas y vectores de enfermedades. Cualidades tales como la herencia vertical de Wolbachia, la velocidad a la que se propaga en las poblaciones que afecta, la capacidad de bloquear la actividad patogénica de diversos microorganismos o de acortar el ciclo de vida de sus hospedadores la señalan como un potencial instrumento para el control de poblaciones de insec - tos y nematodos perjudiciales. ¿Cuáles son las posibilidades que nos ofrece esta pandemia? En la presente contribución se presenta una revisión de los aspectos fundamen - tales de esta infección y sus implicancias prácticas para el manejo de insectos plaga. Esta revisión está basada en el simposio del mismo nombre acontecido en el VIII Congreso Argentino de Entomología.

  19. Posibilidad de cobro de derechos universitarios por actividades de posgrado

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    Alberto Pérez Pérez

    2014-04-01

    Full Text Available Paso a emitir mi dictamen sobre la eventual incidencia de la Ley N° 18.437 en la posibilidad de cobro de derechos universitarios por actividades de posgrado1. Desde ya me adelanto a decir que la citada Ley no ha alterado el marco legislativo dentro del cual fue adoptada la Ordenanza de Carreras de Posgrado de 25-IX-2001 (cuyo art. 10 prevé la mencionada posibilidad y que el referido cobro de derechos universitarios no infringe ninguna norma constitucional ni de los instrumentos internacionales de derechos humanos vigentes para nuestro país.

  20. Deposit of bilayers of LiNiO{sub 2}/alumina by laser ablation; Deposito de bicapas de LiNiO{sub 2}/alumina por ablacion laser

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    Lopez I, J.; Escobar A, L.; Camps, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Camacho L, M.E. [UAEM, Facultad de Quimica, 50000 Toluca, Estado de Mexico (Mexico)

    2006-07-01

    Thin films of lithium nickel oxide (LiNiO{sub 2}) were deposited on silicon substrates at two substrate temperatures: ambient temperature and 165 C ; varying in each case the fluence from 3 up to 20 J/cm{sup 2}. The used target got ready starting from the solid state reaction between NiO and Li{sub 2}O this last in excess of 50% in weight, with the purpose of obtaining stoichiometric LiNiO{sub 2}. Later to the deposit it was carried out a thermal treatment to all the films at 300 C by 2 hours, with the purpose of improving the crystalline structure of the deposited material. The deposits were analyzed by Raman spectroscopy, showing for all the films a wide band with a maximum approximately in 550 cm{sup -1} for the deposits not thermally treated and in 500 cm{sup -1} for the deposits with thermal treatment. Bilayers of LiNiO{sub 2}/Al{sub 2}O{sub 3} were deposited, to be used as cathode material in rechargeable micro batteries, those results of the Raman spectroscopy didn't show variation in the intensity, position and wide of the band shown for the LiNiO{sub 2}. On the other hand the deposits were also analyzed by infrared spectroscopy with the purpose of confirming the Raman results. (Author)

  1. Inmunidad humoral y trasplante renal posibilidades terapéuticas

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    P. Jacqueline Pefaur, Dra.

    2010-03-01

    Por otra parte y basado en el exitoso tratamiento del RAH, se ha planteado mejorar las expectativas de llegar a realizar un trasplante a los pacientes sensibilizados. Esto es posible conseguir aplicando protocolos de desensibilización que se basan en la utilización de las mismas drogas para tratar RAH, consiguiendo ampliar las posibilidades de trasplante. El éxito de éstas es relativo al tipo de protocolos y a la intensidad de la sensibilización. La sobrevida del injerto en esta situación es plausible en la gran mayoría de los casos, sin embargo existe riesgo de presentar rechazo agudo humoral, y más complejo aún es el hecho que la sobrevida a largo plazo de los injertos sigue siendo todavía desconocida.

  2. Posibilidades de los medios tecnológicos para los deficientes visuales

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    Córdoba Pérez, Margarita

    2001-01-01

    De todos es sabido el gran auge y avance que hoy en día están teniendo las denominadas nuevas tecnologías de la información y comunicación. Por lo que desde esta perspectiva, debemos ser conscientes de que las personas con minusvalías tengan las mismas oportunidades, posibilidades de interacción e integración social, escolar y laboral como cualquier otro ciudadano. En este artículo se ofrece una visión global de las posibilidades que nos aporta la tiflotecnología. Se hace un breve recorrido p...

  3. Lasers

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    Milonni, Peter W

    1988-01-01

    A comprehensive introduction to the operating principles and applications of lasers. Explains basic principles, including the necessary elements of classical and quantum physics. Provides concise discussions of various laser types including gas, solid state, semiconductor, and free electron lasers, as well as of laser resonators, diffraction, optical coherence, and many applications including holography, phase conjugation, wave mixing, and nonlinear optics. Incorporates many intuitive explanations and practical examples. Discussions are self-contained in a consistent notation and in a style that should appeal to physicists, chemists, optical scientists and engineers.

  4. Pensamiento único y contabilidad: la posibilidad de la contabilidad como disciplina moral

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    Mauricio Gómez Villegas

    2007-01-01

    Full Text Available Los caminos para consolidar a la contabilidad como disciplina son diversos. La mirada convencional, que busca constituirla en una disciplina científica económica y positivista, está basada en presupuestos que deben juzgarse con rigor argumental, suficiencia histórica e imaginación crítica. La posibilidad de construir a la contabilidad como una disciplina moral, se muestra como una necesidad ante las evidencias de su aporte en la expansión del “pensamiento único”. Este documento muestra las relaciones de la contabilidad por partida doble con el pensamiento único y discute algunos elementos para generar un debate entorno a la posibilidad de la contabilidad como una disciplina moral.

  5. Autodiscriminación condicional, metaconducta y autoclítica: posibilidades investigativas

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    Andrés M. Pérez-Acosta

    2006-01-01

    Full Text Available Se presentan las relaciones entre tres conceptos conductistas relacionados con la autoconciencia: la autodiscriminación condicional (el más general de todos, metaconducta (discriminación condicional de la propia conducta y autocrítica (metaconducta verbal. La adquisición y transferencia de la autodiscriminación condicional ha sido mostrada experimentalmente por el autor en una secuencia investigativa que incluyó animales (palomas y seres humanos no verbales (autistas. Los resultados de estos experimentos llevaron al autor a plantear una disociación entre autoconciencia y lenguaje, más exactamente la posibilidad de autoconciencia no verbal. Finalmente, se ofrecen posibilidades de investigación sobre autodiscriminación condicional y metaconducta, tanto en el campo básico como en el aplicado.

  6. Posibilidades de crecimiento del Islam en América Latina: oportunidades y dificultades

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    Gabriel Ernesto Andrade

    2001-01-01

    Este trabajo elabora un diagnóstico de las posibilidades de crecimiento del Islam en América Latina, considerando las oportunidades y dificultades para su expansión y crecimiento. En este sentido, se analiza como oportunidades de crecimiento la búsqueda de nuevas identidades, las difíciles condiciones sociales latinoamericanas, el paralelismo entre el Islam y elmarxismo y el apoyo financiero proveniente de naciones islámicas. Como dificultades se analiza la rigidez cultural ...

  7. El ser humano y sus posibilidades de construcción desde el cuidado

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    Alacoque Lorenzini Erdmann

    2003-01-01

    Full Text Available El artículo presenta algunas concepciones del ser humano en relación con el cuidado de enfermería. A partir de la organización de la vida se establecen relaciones, interacciones del ser humano, sus límites y posibilidades para el cuidado con la vida, con lo cotidiano y con la naturaleza. Resalta la importancia y el compromiso en la construcción colectiva del ser ciudadano.

  8. Posibilidades estructurales de materiales a base de cal como conglomerante: primeros resultados

    OpenAIRE

    Estrada, Enrique; Barbero, José Miguel

    1986-01-01

    La cal es un material abundante y cuya producción suma a una tecnología muy accesible la ventaja de poder materializarse en pequeñas plantas dispersas, para poder reducir al mínimo la componente de costo debida al transporte. En el presente trabajo se ha planteado la posibilidad de obtener hormigones con fines estructurales, para viviendas de baja altura y que sean de fácil obtención, a base de cal y cenizas volantes o cenizas de cascara de arroz, variando sus proporciones, grados de finur...

  9. Salud bucal y xilitol: usos y posibilidades en caries y enfermedad periodontal en poblaciones "PEPE"

    OpenAIRE

    Panesso Suescún, Ernesto A; Calle Arroyave, María Clara; Meneses Gómez, Edwin J

    2012-01-01

    La caries dental y la enfermedad periodontal constituyen un problema constante que demanda muchos recursos pero que sigue atacando día a día a la población, razón por la cual se deben explorar nuevas posibilidades de prevención y tratamiento complementarias a las ya existentes. El xilitol es un alcohol de 5 carbonos derivado de la D-xilosa cuyo mecanismo de acción es inhibir el crecimiento bacteriano, principalmente de Streptococcus mutans en la saliva y la biopelícula además de mejorar el fl...

  10. Enseñando comunicación con mapas conceptuales: experiencias y posibilidades

    Directory of Open Access Journals (Sweden)

    Carlos Araya Rivera

    2012-01-01

    Full Text Available Este ensayo reseña algunas experiencias en el uso de mapas conceptuales para la enseñanza de las Ciencias de la Comunicación, desarrolladas por el autor en tres cursos impartidos en la Universidad de Costa Rica entre el 2007 y el 2010. Se reflexiona en cuanto a la aplicación de esta herramienta y sus posibilidades didácticas, y se ofrece algunas recomendaciones para aprovechar mejor el potencial de los mapas conceptuales.

  11. Población con discapacidad: Posibilidades y Desafíos para su Estudio

    OpenAIRE

    Scheuermann, Helga

    2013-01-01

    El presente artículo enfatiza en examinar las fuentes de datos existentes en la República Argentina y en una de sus provincias (Tucumán) sobre la población con discapacidad, con el fin de abordar estudios sobre las condiciones de vida de estas poblaciones. Se realiza un recorrido por los censos, encuesta nacional de discapacidad y fuentes provinciales de información, con el objetivo de establecer y evaluar las posibilidades de estudios comparativos, evolutivos y/o específicos que puedan co...

  12. Investigación Crítica: Desafíos y Posibilidades

    Directory of Open Access Journals (Sweden)

    Fractalitats en Investigació Crítica (FIC

    2005-11-01

    Full Text Available La emergencia de las ciencias sociales está ligada a la constitución de una red de tecnologías, conocimientos, prácticas y discursos para regular y gobernar la sociedad; desarrollando formas de control en el que las ciencias sociales juegan un papel central. La actual sociedad del conocimiento gestiona la producción de conocimiento científico que maximiza las aportaciones coherentes con el pensamiento hegemónico y dificulta el desarrollo de perspectivas críticas (Slaughter y Leslie, 1997, 2001. Las ciencias sociales se encuentran en la paradoja de cuestionar los fundamentos de aquello en que, de un modo u otro, participan constitutivamente. El desarrollo de la sociedad post-fordista y nuestra localización en la barriga del monstruo (Haraway, 1991 plantea la necesidad de una reflexión sobre el contexto, las posibilidades y las formas de un trabajo crítico en el presente marco institucional. Exploramos principios metodológicos y formas de investigación a considerar en el planteamiento de una ?investigación crítica?, a la vez que nos preguntamos por las posibilidades mismas del trabajo académico de carácter crítico.

  13. Norma Z39.50, actualidad, posibilidades. ¿Es necesario un cambio de actitud?

    Directory of Open Access Journals (Sweden)

    de la Rosa Piñero, A.

    1998-12-01

    Full Text Available Z39.50 standard based systems technology offers many quite promising possibilities for the future: systems connectivity, retrieval of high structured information, redefinition of applications (as search engines, agents and so forth, integration within proprietary software, online or CD-ROM publishing systems, protocols... However, the situation nowadays is very little advantageous in order to develop Z39.50 based systems. This paper analyses the range of possibilities offered by the mentioned standard

    La tecnología de los sistemas basados en la norma Z39.50 ofrece numerosas posibilidades, a priori bastante prometedoras. Conectividad de sistemas, recuperación de información muy estructurada, redefinición de aplicaciones (robots de búsqueda, agentes..., integración con sistemas propietarios, edición online y CD-ROM, protocolos... Sin embargo, en la actualidad se está favoreciendo muy poco el desarrollo de sistemas basados en esta norma. En este artículo se analizan las diversas posibilidades que ofrece la misma.

  14. Marx, Keynes y la posibilidad de crisis Marx, Keynes and the Possibility of crisis

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    Kenway Peter

    1992-12-01

    Full Text Available En este artículo Peter Kenway plantea que las teorías desarrolladas por Marx y Keynes para explicar el funcionamiento de la economía capitalista son complementarias. Debido a la existencia del dinero, en Marx la crisis económica es siempre una posibilidad que puede ocurrir cuando una ruptura en el circuito del capi tal separa el acto de compra del de venta. Esta posibilidad emerge de la anarquía de la producción capitalista, su característica fundamental, y plantea interrogantes sobre el nivel de
    demanda requerido para realizarla. La teoría de la demanda efectiva en Keynes sostiene que la crisis ocurre cuando los flujos y escapes de inversión no proveen la demanda
    agregada suficiente para realizar el producto. Según el autor la característica común a ambos enfoques es así el
    intento por construir una teoría monetaria de la producción capitalista, en la que la teoría de la posibilidad complementa la de la demanda efectiva en la explicación de porqué el dinero desempeña un papel operativo en el proceso de producción. A su vez, la teoría de la demanda efectiva complementa a la teoría de la posibilidad para explicar el nivel de demanda que se requiere para la realización del producto entre los diferentes departamentos de la
    economía. Así, en el análisis de Kenway, Marx y Keynes comparten un mismo terreno en cuanto a la teoría de la posibilidad de crisis. La teoría de la realidad sería campo para otro análisis.In this article Peter Kenway states that the theories developed by Marx and Keynes to explain the operation of the capitalistic economy complement each other. Due to the existence of money, in Marx the economic crisis is always a possibili ty that may occur when a rupture in the capi tal circuit separates the act of purchasing from the act of selling. This possibility
    arises from the anarchy of capitalistic production, its basic
    characteristic, and raises questions on the demand level

  15. Nuevas posibilidades y retos para la investigación y el conocimiento en universidades

    Directory of Open Access Journals (Sweden)

    Álvaro Enríquez Martínez

    2013-01-01

    Full Text Available Este artículo analiza y reflexiona sobre la universidad como institución sometida actualmente a tensiones externas e internas, dada su misión investigativa y su consecuente producción de conocimiento. Las tensiones externas provenientes del sector gubernamental pretenden que la universidad acreciente y redirija su actividad investigativa hacia la búsqueda de un conocimiento innovador o aplicado a problemas relacionados con el desarrollo económico social. Las tensiones internas se refieren a la manera como la universidad gestiona el conocimiento que produce. Esta situación le demanda a la universidad estrategias que le permitan ser pertinente socialmente, sin dejar los principios que la fundamentan. En consecuencia con lo planteado, se mencionan algunas dificultades y posibilidades para realizar esta gestión.

  16. Periodismo salvadoreño: de la intolerancia política a las posibilidades informativas

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    Mario Alfredo Cantarero

    2001-01-01

    Full Text Available En este artículo se plantea la historia reciente del periodismo salvadoreño: antes de los acuerdos de paz y después de los acuerdos de paz. Se sostiene que durante la guerra el periodismo se realizaba con las limitaciones que impuso la intolerancia política. A partir de los acuerdos de paz, por la distensión política y la instauración de la democracia, el periodismo tiene mayores posibilidades de realizar un trabajo más profesional. Sin embargo, profesionalizarlo más implica superar dificultades propias del gremio de periodistas, que se encuentran el orden de la responsabilidad social, el manejo técnico, el respeto a las leyes y a la asunción de normas éticas.

  17. Justicia y derechos humanos: posibilidades de una reflexión desde los planteamientos rawlsianos

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    Paulina Morales Aguilera

    2009-01-01

    Full Text Available El presente artículo brinda una reflexión sobre los derechos humanos a la luz del pensamiento de John Rawls y sus planteamientos en torno a la justicia. En efecto, hablar de derechos humanos es hacer referencia indiscutiblemente a una noción de justicia que les subyace.Y hablar de justicia nos remite, indefectiblemente, a Rawls, quien en 1971 estremece el ambiente filosófico con su ya famosa Teoría de la justicia. De ella se intenta rescatar aportes para una lectura de los derechos humanos, especialmente en relación con los principios de una justicia como equidad y con las posibilidades de configurar un sujeto de derechos al amparo de la consideración de la personalidad moral del ser humano.

  18. Mujeres, ciencia y medios de comunicación: posibilidades de un directorio de mujeres expertas

    Directory of Open Access Journals (Sweden)

    Jorge García Marín

    2007-01-01

    Full Text Available En la 4ª Conferencia Mundial sobre las Mujeres, celebrada en Pekín en septiembre de 1995, patrocinada por las Naciones Unidas, en el documento "Las mujeres y los medios de comunicación" ( se presentan varias reflexiones que inciden, por una parte, en incrementar la participación y el acceso de las mujeres a la expresión y a la toma de decisiones en y a través de los medios; y, por otra, en promover una imagen equilibrada y no estereotipada de ellas en los medios de comunicación. En este trabajo, partiendo de la constatación de la presencia de las mujeres en el cam po científico, reflexionamos sobre la necesidad de una Base de Datos de Mujeres Expertas como magnífica posibilidad para visibilizarlas en el discurso mediático.

  19. TIC y Sostenibilidad: Obstáculos y posibilidades para los educadores ambientales

    Directory of Open Access Journals (Sweden)

    Fernando Ojeda-Barceló

    2011-01-01

    enfrentan, las actitudes y valoración de aquellas, sus ventajas e inconvenientes y su integración concreta en la programación de aula. Ello se hizo a través de una investigación que parte de la constitución de una comunidad virtual internacional, participando un total de 232 educadores ambientales de doce países iberoamericanos que respondieron a una encuesta «on line» con items cerrados y abiertos. Las categorías de análisis se generaron a partir de los objetivos del estudio y las subcategorías en las respuestas abiertas se formularon de forma inductiva-deductiva. Los resultados evidencian una alta consideración de los educadores hacia las TIC aunque la realidad de su uso es menos optimista, dado que existe un bajo nivel de preparación y se enfrentan a dificultades técnicas, organizativas, económicas o, incluso, de convicción sobre su utilidad en sustitución del contacto con el medio natural, lo que hace que el uso de las TIC no sea lo frecuente que sería deseable ni se aprovechan las múltiples posibilidades de la web 2.0.

  20. Posibilidades estructurales de materiales a base de cal como conglomerante: primeros resultados

    Directory of Open Access Journals (Sweden)

    Estrada, Enrique

    1986-11-01

    Full Text Available Lime is a plentiful material which production combine a very accessible technology with the advantage that it must be prepared in little disperse plants, so that the transport charges can be reduced to the minimum. This work expound the possibility to obtain concretes with structural purposes, for housing of scarce height, of easy obtention, basically from flying ashes or rice husk ashes, varying its proportions and fineness degree and studying the initial and final resistance. Good results have been obtained mainly with rice husk ashes and lime, with 60 days resistance higher than 15 Mpa.La cal es un material abundante y cuya producción suma a una tecnología muy accesible la ventaja de poder materializarse en pequeñas plantas dispersas, para poder reducir al mínimo la componente de costo debida al transporte. En el presente trabajo se ha planteado la posibilidad de obtener hormigones con fines estructurales, para viviendas de baja altura y que sean de fácil obtención, a base de cal y cenizas volantes o cenizas de cascara de arroz, variando sus proporciones, grados de finura y estudiando la influencia de distintos factores en la resistencia inicial y final. Se han obtenido buenos resultados, principalmente con ceniza de cascara de arroz y cal con resistencias a 60 días superiores a los 15 MPa.

  1. Evolución de planetas gigantes y posibilidades de su detección directa

    Science.gov (United States)

    Brunini, A.; Benvenuto, O. G.

    Desde la reciente detección de planetas gigantes orbitando estrellas cercanas de tipo solar por medio de efecto Doppler, uno de los principales problemas, en cuanto al estudio de los sistemas planetarios extrasolares, se refiere a la posibilidad de obtener evidencia directa de su existencia. Esto parece ser factible gracias a que en un futuro cercano entrarán en operación algunos telescopios especialmente adecuados a estos propósitos. Por tal motivo, hemos comenzado desde hace un tiempo un esfuerzo en cuanto al estudio de la evolución planetaria. A tales efectos hemos adaptado el código de evolución estelar de nuestro Observatorio al caso planetario. Las principales diferencias entre el caso estelar y el planetario se encuentran en la ecuación de estado. A tales fines hemos incluído la reciente ecuación de estado de Saumon, Chabrier y Van Horn, las opacidades radiativas de Guillot et al., procesos de quema de Deuterio, etc. También se ha considerado la posible existencia de fases de hielo y roca en el interior planetario. Por el momento hemos despreciado los efectos de la rotación planetaria. Con este código hemos computado la evolución de planetas con masas desde 10 hasta 0.3 masas de Júpiter. Utilizando nuestros resultados numéricos discutimos la detectabilidad de estos objetos en condiciones realistas.

  2. "No debemos renunciar a la posibilidad de ir dejando huellas de nuestro paso"

    Directory of Open Access Journals (Sweden)

    Alicia H. Puleo

    2013-07-01

    Full Text Available Entrevista realizada por Iolanda Martínez Suárez, en la que Alicia H. Puleo habla de que en la sociedad capitalista occidental de hoy en día, en la que los medios no dejan de estimular nuestro deseo d consumir y de disfrutar –tanto de objetos materiales como de nuestros cuerpos– y crean la falsa ilusión de que se ha conseguido la libertad absoluta para todo el mundo, tenemos que intentar conservar el espíritu crítico. En esos tiempos de una supuesta libertad sexual, las mujeres todavía tienen que luchar por ser reconocidas como personas. Alicia H. Puleo, que se autodefine como “ecofeminista e ilustrada”, propone que adoptemos una actitud que combina la mesura y la conciencia de una autonomía feminista. En esta entrevista se habla e mujeres y educación, además de los roles de género y la dominación masculina (desde la ciencia sobre el cuerpo de la mujer. Puleo sugiere que aprovechemos tanto los medios tradicionales como las posibilidades que la nueva tecnología nos ofrece para luchar contra los estereotipos.

  3. Posibilidades de aplicación en la investigación educativa

    Directory of Open Access Journals (Sweden)

    Julia Boronat Mundina

    2005-01-01

    Full Text Available La técnica del análisis de contenido resulta una metodología muy adecuada para iniciar a los alumnos de postgrado en tareas de investigación, trabajo que, en ocasiones, culmina con la elaboración de la tesis doctoral. La temática, objeto de estudio, puede ser muy rica y diversificada: textos escolares de distintos niveles educativos y áreas de conocimiento, recursos y materiales escolares, prensa escrita y lúdica, nuevas tecnologías, publicidad, entrevistas, diarios de campo, canciones, etcétera. La utilización rigurosa de esta técnica permite adentrarse en los entresijos del contenido, delimitar sus dimensiones y variables y crear un sistema categorial que permita ubicar las diversas partes del mensaje en la categoría correspondiente. El trabajo presentado es una muestra fehaciente de las posibilidades y logros obtenidos mediante la aplicación de esta técnica. Recoge una muestra de trabajos de diferente nivel de complejidad: trabajos de iniciación, trabajos de consolidación y tesis doctoral.

  4. El espacio público cotidiano y la posibilidad de la producción colectiva

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    Lígia Milagres

    2011-12-01

    Full Text Available El enfoque del artículo es la producción del espacio público cotidiano, que es el que se encuentra en las inmediaciones de la vivienda, entre el espacio privado y el espacio público destinado a actividades de convivencia y de ocio. Ubicado en un punto ciego de la regulación urbanística y de las actividades de todos los días, este tipo de espacio puede ser el enfoque de intervenciones decididas por las personas que lo viven diariamente. Con el objetivo de discutir la posición de los habitantes urbanos delante la producción de este tipo de espacio, se analizan dos situaciones que involucran espacios posibles de uso localizados en ambientes urbanos residenciales de la ciudad de Belo Horizonte (Brasil. Partiendo de la constatación de posiciones más o menos comprometidas se discute la posibilidad de una producción colectiva del espacio público cotidiano, o sea, una producción que no depende de la estructura burocrática de la administración municipal y que ocurre de acuerdo con las negociaciones y acciones directas de individuos o grupos.

  5. Posibilidades y limitaciones de la educación intercultural en contexto mapuche.

    Directory of Open Access Journals (Sweden)

    Segundo Quintriqueo M

    2009-07-01

    Full Text Available El presente artículo tiene por objeto la educación intercultural en contexto mapuche, donde se exponen antecedentes teóricos y prácticos referidos a su origen en América Latina y Chile, asociado al carácter histórico, monocultural y centralizado de la educación. La educación intercultural es definida en relación a las demandas históricas de las familias y comunidades para mejorar la educación y valorar el patrimonio cultural mapuche en la educación escolar. Como resultado se presenta un análisis sobre las posibilidades y limitaciones de la educación intercultural en relación a la coexistencia de racionalidades: mapuche y no mapuche en contexto intercultural. Estas racionalidades generan una distancia epistemológica en la definición de contenidos y finalidades educativas para la formación de persona en contexto de relaciones interétnicas e interculturales.

  6. Los pequeños y medianos citricultores de Concordia, Argentina. Dificultades y posibilidades de permanencia

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    Paula Palacios

    2010-12-01

    Full Text Available En Argentina la producción frutícola se ha posicionado como uno de los sectores más dinámicos de la agricultura y ha adquirido relevancia regional, con particularidades locales. El trabajo aborda la problemática de la producción de cítricos dulces ubicado en el denominado corredor citrícola del río Uruguay, Argentina. Focaliza el análisis en los pequeños y medianos productores, especialmente del departamento de Concordia y en el posicionamiento diferencial de los mismos según su integración en los eslabones de la cadena agroindustrial. Asimismo indaga acerca de las dificultades que afrontan y las estrategias que implementan y reflexiona sobre las posibilidades de permanencia en el tiempo de este segmento de productores. Se utilizan técnicas de análisis cualitativas, aplicadas a entrevistas en profundidad efectuadas a informantes calificados, y la revisión de bibliografía pertinente.

  7. Posibilidades de Facebook en la docencia universitaria desde un caso de estudio

    Directory of Open Access Journals (Sweden)

    María Cristina López de la Madrid

    2017-09-01

    Full Text Available El presente estudio descriptivo tuvo como objetivo identificar las posibilidades de la red social Facebook en el ámbito de la docencia. Para ello, diseñamos y validamos una encuesta de reactivos cerrados aplicada a una muestra de 142 docentes del nivel superior. Trabajamos, además, una pregunta abierta a partir de la cual se generaron categorías de análisis que complementaron los resultados cuantitativos representados a través de frecuencias en porcentajes. Algunos de los hallazgos más significativos refieren, por un lado, la alta frecuencia de uso de Facebook (diariamente, y el dominio entre medio y alto que tiene la mayoría de los docentes (90.92% en el uso de esta red social; por otro, encontramos una amplia variedad de usos de Facebook, tanto en el proceso de enseñanza como en las demás actividades de los docentes, lo cual puede ser del interés de aquellos que quieran implementar esta red social a su práctica. Identificamos algunos factores negativos en el uso de ella, como la falta de estructuración y el exceso de ruido visual. Concluimos que, con una dirección y un diseño adecuados, Facebook puede propiciar ambientes de aprendizaje dinámicos y atractivos para los estudiantes de educación superior.

  8. LA FORMACIÓN DE LA ESTRATEGIA EN MINTZBERG Y LAS POSIBILIDADES DE SU APORTACIÓN PARA EL FUTURO

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    IVÁN A. MONTOYA RESTREPO

    2009-01-01

    Full Text Available El presente artículo de revisión se orienta a reconocer los principales aportes relacionados con la forma como la estrategia es elaborada y los ciclos que producen su formación, con particular atención al trabajo de Henry Mintzberg. Posteriormente, se presentan los principales puntos de debate del autor con los enfoques habituales y las posibilidades para el campo que su aportación ofrece.

  9. LA FORMACIÓN DE LA ESTRATEGIA EN MINTZBERG Y LAS POSIBILIDADES DE SU APORTACIÓN PARA EL FUTURO

    OpenAIRE

    IVÁN A. MONTOYA RESTREPO

    2009-01-01

    El presente artículo de revisión se orienta a reconocer los principales aportes relacionados con la forma como la estrategia es elaborada y los ciclos que producen su formación, con particular atención al trabajo de Henry Mintzberg. Posteriormente, se presentan los principales puntos de debate del autor con los enfoques habituales y las posibilidades para el campo que su aportación ofrece.

  10. INVESTIGACIÓN NARRATIVA EN LA ENSEÑANZA DE LA BIOLOGÍA: POSIBILIDADES Y ASPECTOS CRUCIALES

    Directory of Open Access Journals (Sweden)

    Rebeca Urazan

    2015-12-01

    Full Text Available La investigación narrativa en educación, ha adquirido gran importancia debido a las posibilidades que presenta para comprender la práctica docente de una manera alternativa, dotándola de valor y dando voz a la experiencia.   Es desde este aspecto, que hemos desarrollado este texto, queriendo dar a conocer las posibilidades, que nosotros mismos hemos hallado en este tipo de investigación, para comprender el quehacer del profesor de ciencias (en especial de biología. Creemos, que al dar valor a la experiencia y relatos de los profesores, estamos reconociendo su papel como productores legítimos de conocimientos. Es rescatando la voz del profesor, como se empiezan a constituir nuevos escenarios para la dignificación de la profesión docente.   En esta ponencia, presentaremos algunas de las investigaciones por nosotros realizadas desde este ámbito. En este artículo de  revisión procuraremos dar algunas pautas para tener en cuenta tanto en el desarrollo de este tipo de investigaciones, así como algunas posibilidades de análisis narrativo. Adicionalmente compartiremos algunas inferencias que hemos logrado en los relatos recolectados, en relación con la práctica docente e identidad versus formación inicial y continua.

  11. INVESTIGACIÓN NARRATIVA EN LA ENSEÑANZA DE LA BIOLOGÍA: POSIBILIDADES Y ASPECTOS CRUCIALES

    Directory of Open Access Journals (Sweden)

    Rebeca Urazán

    2015-12-01

    Full Text Available La investigación narrativa en educación, ha adquirido gran importancia debido a las posibilidades que presenta para comprender la práctica docente de una manera alternativa, dotándola de valor y dando voz a la experiencia.   Es desde este aspecto, que hemos desarrollado este texto, queriendo dar a conocer las posibilidades, que nosotros mismos hemos hallado en este tipo de investigación, para comprender el quehacer del profesor de ciencias (en especial de biología. Creemos, que al dar valor a la experiencia y relatos de los profesores, estamos reconociendo su papel como productores legítimos de conocimientos. Es rescatando la voz del profesor, como se empiezan a constituir nuevos escenarios para la dignificación de la profesión docente.   En esta ponencia, presentaremos algunas de las investigaciones por nosotros realizadas desde este ámbito. En este artículo de  revisión procuraremos dar algunas pautas para tener en cuenta tanto en el desarrollo de este tipo de investigaciones, así como algunas posibilidades de análisis narrativo. Adicionalmente compartiremos algunas inferencias que hemos logrado en los relatos recolectados, en relación con la práctica docente e identidad versus formación inicial y continua.

  12. SITUACIÓN DIDÁCTICA Y POSIBILIDADES DEL CLIMOGRAMA COMO RECURSO DIGITAL

    Directory of Open Access Journals (Sweden)

    Daniel David Martínez Romera

    Full Text Available RESUMEN:En el ámbito de la Didáctica de la Geografía, la adopción de la interactividad propia de la Web, en las aplicaciones disponibles para facilitar su aprendizaje, todavía se encuentran en un estadio inicial; lo que dificulta aprovechar algunas posibilidades inherentes al medio tecnológico, como es la simulación numérica, la manipulación de datos. En este sentido, se presenta una aplicación didáctica que intenta reducir dicha brecha, a partir de una propuesta concreta: el climograma, tema en el que los recursos disponibles, como muestra el análisis de las fuentes más extendidas, son un claro ejemplo de la situación de retraso descrita. PALABRAS CLAVE:Didáctica, Geografía, Climograma, Internet, Simulación. ABSTRACT:In the field of Teaching Geography, the applications available to facilitate its learning are still at an early stage relative to adopting interactivity of the Web itself; this fact hinders take advantage of this resource, such as in the case of the data manipulation for numerical simulation. In this sense, we offer an educational application that attempt to reduce this gap, from a concrete proposal: the climograph, subject in which the available resources, as its analysis shows, are a clear example of the situation delay described. KEY WORDS:Didactics, Geography, Climograph, Internet, Simulation. RÉSUMÉ:Au secteur de la didactique de la géographie, accepter l ́interactivité propre de l ́Internet et de la toile WEB, les applications utilisables pour faciliter l ́apprentissage se trouvent encore à l ́état initial, ce qui empêchent d ́appliquer quelques possibilités propres inhérentes du moyen technologique, comme la simulation numérique ou l ́utilisation des données. En tout cas se présente une application didactique qui essaie de réduire cet espace vide, proposant une idée exacte comme le climograma, sujet dans lequel les ressources utilisables, comme échantillon les analyses des sources

  13. Posibilidades del pretensado de las rocas en excavaciones subterráneas

    Directory of Open Access Journals (Sweden)

    Peironcely Aguilar, José Manuel

    1964-02-01

    Full Text Available In civil engineering the prestressing methodology enables the engineer to induce in the structure states of stress that are equal and opposite to those due to the applied forces. In underground excavations, when this modifies the state of stress of the rock masses, it is also possible to apply compression stresses which, if rightly orientated, improve the stability of the rock. In this paper details are given of the methods of calculation and execution technology of a project which sought to nullify the thrusts of the vault of an underground power station, so that the stability of the side walls should not be impaired. It is reasoned why it was decided to prestress the rock as a method of achieving this object, and the features and factors which were involved are described. Information is also given of how the factors of safety of certain mountain massifs were improved, after the excavation of the above mentioned power station gave reason to believe that parts of the mountain rock might thereby become heavily overloaded.La técnica del pretensado en las obras civiles, ofrece al Ingeniero la posibilidad de crear unos esfuerzos tales que introduzcan en las estructuras estados tensionales iguales y contrarios a los que se prevea han de producir las solicitaciones. En el campo de las excavaciones subterráneas, y cuando la ejecución de las mismas modifica el estado tensional del macizo «in situ», es también posible crear unos esfuerzos de compresión que, dirigidos adecuadamente, mejoren las condiciones de estabilidad de dicho macizo. En el presente artículo se exponen las bases de cálculo y el sistema de ejecución para conseguir que la descarga de los empujes de la bóveda de u na central subterránea no alterasen las condiciones de estabilidad de los hastiales. Se detallan las razones que motivaron la elección del pretensado de la roca como vehículo para conseguir tal fin y los elementos que intervinieron en su ejecución. También se

  14. Determinación de restricciones y posibilidades ambientales para la expansion del transporte de gas natural en Colombia

    Directory of Open Access Journals (Sweden)

    Ángel Sanint Enrique

    2011-11-01

    Full Text Available En la línea de la Evaluación Ambiental Estratégica, EAE, se desarrolló un método para la determinación de restricciones y posibilidades ambientales en proyectos de transporte de gas natural por ductos, basado en el uso de herramientas de análisis territorial aplicadas sobre la plataforma SIG (Sistema de Información Geográfica, incorporando criterios ambientales que a escala 1:500.000 apoyarán la toma de decisiones en el nivel de planeación y propiciarán la elaboración del plan de expansión para el transporte de gas natural en Colombia. Para esto, se definió el concepto de ambiente a partir de un Modelo Analítico preexistente; se delimitó un área con posibilidades para la expansión de la red de transporte de gas natural incorporando nuevos trazados; se seleccionaron las variables y factores que complementaban el Modelo Analítico; se definió la estructura de preferencias a partir de una encuesta a expertos; se determinaron las restricciones nacionales y se construyeron superficies numéricas síntesis de critici dad ambiental para cada dimensión. Como resultado, se obtuvieron 5 superficies síntesis, una por cada dimensión, y una superficie final para Colombia, con restricciones y posibilidades ambientales. Además se propusieron análisis complementarios para establecer prioridades en la gestión ambiental.

  15. Posibilidades y limitaciones de la educación Intercultural Bilingüe en Bolivia y Perú

    OpenAIRE

    Miranda Saucedo, Tomas Francisco

    2012-01-01

    La tesis estudia las posibilidades de la Educación Intercultural Bilingüe – E.I.B. en Bolivia y Perú; considerando la importancia que tiene como propuesta constitutiva de los sistemas educativos, de la legislación educativa y de ser el modelo más innovador que ha tenido la educación indígena en las últimas décadas. La investigación incluye la participación decisiva que han tenido las organizaciones indígenas y sindicales; al asumir entre sus reivindicaciones más importantes el derecho a la ed...

  16. La naturaleza jurídica de la posibilidad de prescripción de los delitos

    OpenAIRE

    Cerrada Moreno, Manuel

    2017-01-01

    Tradicionalmente, la prescripción de los delitos ha sido estudiada como una institución a la que se ha asignado una naturaleza jurídica material o procesal para derivar de ello consecuencias mediante el sistema lógico-deductivo, pero de este modo se llega a resultados que no son válidos, pues contradicen lo dispuesto en normas con rango jerárquico superior en el ordenamiento jurídico. En cambio, la posibilidad de prescripción puede ser vista como una cualidad de los delitos que afecta a su pu...

  17. Internet: entre las posibilidades de lo intangible, la dinámica social y las reconfiguraciones del capital

    Directory of Open Access Journals (Sweden)

    Horacio Edgardo Correa Lucero

    2014-01-01

    Full Text Available En este artículo se esbozan elementos teóricos para el análisis de las nuevas tecnologías y en especial de Internet, dada la interrelación e influencia continua entre sociedad y tecnología. Ello permite abordar Internet como una serie de tecnologías digitales caracterizadas por un conjunto de capas imbricadas de carácter intangible y tangible. La hipótesis de este trabajo es que Internet ha puesto en crisis las formas clásicas de valoración del capital en relación a mercados signados directamente por precios y a la propiedad privada. De ahí que se concluya que los procesos en curso de configuración de la web sean producto de un entrecruzamiento entre las posibilidades que brindan los códigos técnicos en Internet desde sus inicios y la lógica del capital que, en cada caso particular, asume matices de ambas formas. De esto se sigue la importancia de analizar las particularidades del diseño y construcción de tecnologías, para comprender, a raíz de ello, las potencialidades y posibilidades políticas implicadas en los códigos técnicos del conjunto de tecnologías que componen Internet.

  18. Titulación académica y posibilidades de acceso al primer empleo

    Directory of Open Access Journals (Sweden)

    ET. OTROS

    2009-11-01

    Full Text Available RESUMEN: El presente artículo realiza una revisión sobre el estado de la cuestión de la temática focalizada y recoge una investigación de carácter cualitativo. La técnica de recogida de información utilizada ha sido la entrevista. La investigación abordada versa sobre un estudio de caso, acerca de la titulación académica de los empleados de una empresa del sector del comercio en España y sus posibilidades de acceso al primer empleo.De la investigación se desprende que existe una estrecha relación entre la formación y el empleo llegando a convertirse en uno de los mayores condicionantes para la consecución y mantenimiento de éste. Los titulados medios y universitarios no encuentran dificultades para optar al primer empleo en el sector del comercio en España, debido a que todos presentan un nivel de estudios superior al solicitado para el trabajo que realizan en los primeros años de su vida laboral. A pesar de que el nivel de estudios no asegura la obtención del primer empleo coloca a las personas en una situación privilegiada para lograrlo, así la formación ofrece una predisposición para conseguirlo. Con todo, es recomendable desarrollar procedimientos para ofrecer una educación inicial más adaptada al contexto laboral de cada titulación académica que propicien un grado de exigencia coherente con la capacitación profesional.ABSTRACT: The present article is a review on the state of art of the topic starting from a qualitative approach. The technique Lised to collect data was the interview. This is a case study about the academic degrees of the employees of a company in the business sector in Spain and their possibilities of obtaining their first job.One conclusión is the cióse relationship between training and employment and how the former is one of the greatest conditioners in attaining and maintaining the latter. Persons with secondary diplomas and university degrees have no difficulties in gaining their first job

  19. Las pedagogías críticas: un lenguaje de la posibilidad para la universidad y sus maestros

    Directory of Open Access Journals (Sweden)

    Piedad Ramírez-Pardo

    2012-01-01

    Full Text Available El ensayo destaca los aportes de las pedagogías críticas para repensar el papel de la universidad y sus maestros en la sociedad. Reivindica la autonomía, la crítica, la libertad académica y la recuperación del maestro como intelectual transformativo, con capacidad para pensar la sociedad y construir un discurso que conjugue el lenguaje de la crítica con el de la posibilidad; maestros que se perciban a sí mismos con capacidad y opciones para enfrentar constructivamente la complejidad del mundo social y potenciar desde su rol, con sus estudiantes la transformación del orden establecido.

  20. La teoría de los diferenciales de Salomon Maimon, la pregunta quid juris y la posibilidad de la metafísica como ciencia

    Directory of Open Access Journals (Sweden)

    Hernán Pringe

    2016-06-01

    Full Text Available Este trabajo estudia la teoría de los diferenciales de Salomon Maimon como respuesta a la cuestión quid juris y a la vez como clave para la fundamentación de la posibilidad de la metafísica como ciencia. Se reconstruye primero la crítica de Maimon al tratamiento kantiano de la pregunta quid juris. Luego, se analiza la respuesta del propio Maimon a esa pregunta, para establecer finalmente cómo tal respuesta abre el camino para la explicación de la posibilidad de la metafísica como ciencia.

  1. Acceso abierto: posibilidades y retos epistemológicos para las publicaciones científicas en la red

    Directory of Open Access Journals (Sweden)

    Feltrero, Roberto

    2009-06-01

    Full Text Available The different proposals for Open Access to scientific publishing on the Internet offer undeniable advantages for the scientific practices of communication, publishing, dissemination and validation of scientific results. However, neither these practical advantages, nor the economical and moral reasons that are usually alleged to justify the Open Access movement, seem to be enough to strengthen and extend this system to the whole scientific community. Those reasons might be supplemented, from a philosophical perspective, by contemplating the epistemological potential of Open Access and its practical possibilities for an Open Peer-Review system. This study will help us consider which possibilities can be explored and exploited within the Open Access Movement in order to unify proposals and methodologies and, by means of these, provide a valuable epistemological alternative to the current commercial toll-access system.Las propuestas de acceso abierto a las publicaciones científicas en Internet presentan innegables ventajas para las labores de comunicación, publicación, difusión y contrastación de los resultados científicos. Sin embargo, ni estas ventajas prácticas, ni las razones económicas y morales que habitualmente se esgrimen para justificar la propuesta del acceso abierto, parecen ser suficientes para afianzar y extender este sistema a toda la comunidad científica. Dichas razones pueden complementarse, desde la filosofía, con una revisión de las posibilidades epistemológicas del acceso abierto y sus propuestas sobre los sistemas abiertos de revisión de los artículos científicos. Este estudio servirá para comprender las posibilidades que el movimiento del acceso abierto puede explorar y explotar para unificar sus propuestas y sus metodologías de forma que pueda constituirse en una alternativa epistemológicamente más valiosa que el actual sistema de publicación comercial de acceso restringido.

  2. Lasers '89

    International Nuclear Information System (INIS)

    Harris, D.G.; Shay, T.M.

    1990-01-01

    This book covers the following topics: XUV, X-Ray and Gamma-Ray Lasers, excimer lasers, chemical lasers, nuclear pumped lasers, high power gas lasers, solid state lasers, laser spectroscopy. The paper presented include: Development of KrF lasers for fusion and Nuclear driven solid-state lasers

  3. Comportamiento no verbal en personas con enfermedad de Parkinson como posibilidad de mejoramiento de la comunicación

    Directory of Open Access Journals (Sweden)

    María de los Angeles Bacigalupe

    2018-05-01

    Full Text Available Se propone analizar distintas cuestiones comportamentales que afectan la comunicación de las personas con Enfermedad de Parkinson (EP en relación a su entorno, en función del desarrollo de una propuesta de comunicación basada en el marco de una antropología relacional. Se realizó una revisión bibliográfica con una propuesta teórica. El comportamiento es concebido como una relación co-constructiva entre individuo y entorno y la comunicación como condición de esta relación. Son revisados avances y opiniones acerca de la gestualidad y el comportamiento no verbal en personas con EP, tanto desde aquellos que ponen el acento en el déficit como un signo no motor del Parkinson como a partir de los estudios que indagan estas cuestiones con la idea de estrategias compensatorias. Tomando como marco teórico la postura relacional del comportamiento humano, el artículo se propone una mirada co-constructiva del comportamiento no verbal en las personas con EP, propuesta que promueve la idea de salud en el contexto de la enfermedad crónica a través de las mismas posibilidades que las características del comportamiento ofrecen, fundamentalmente del fenómeno de la kinesia paradojal.

  4. La participación ciudadana en la ordenación del territorio: posibilidades y limitaciones

    Directory of Open Access Journals (Sweden)

    Fernando Manero Miguel

    2010-01-01

    Full Text Available El concepto de participación ciudadana ocupa en nuestros días una posición muy destacada en el debate sobre el modo de entender y ejecutar las políticas públicas tanto por el margen de posibilidades que se le reconoce en el sistema regulador como por las incertidumbres, contradicciones y conflictos que genera. Identificado asimismo como uno de los pilares en los que se fundamentan los enfoques aplicados a la gobernanza y a la ordenación integrada y sostenible del territorio, conviene interpretarlo en función de las diferentes modalidades de aplicación de que es susceptible y de los resultados obtenidos en un panorama muy abierto y cambiante de objetivos, experiencias y de estilos de gobierno en las escalas locales de actuación. El conocimiento y valoración de iniciativas específicas de participación en el marco del proyecto de cooperación estratégica de las ciudades de Valladolid y Palencia aporta ideas significativas en torno a un tema tan complejo y controvertido como interesante desde el punto de vista territorial.

  5. Las posibilidades educativas de la curación de contenidos: Una revisión de literatura

    Directory of Open Access Journals (Sweden)

    Diana Juárez Popoca

    2017-09-01

    Full Text Available El objetivo de este trabajo es analizar la implementación de experiencias de curación de contenidos en la práctica educativa, partiendo de la premisa de que esta actividad no se reduce a la gestión de información, sino que incide en el aprendizaje y la capacidad de los individuos para desenvolverse de manera óptima en el ámbito de los medios digitales modernos. La metodología utilizada es la revisión sistemática de literatura. Mediante una búsqueda acotada al período 2011-2016, se localizaron 19 estudios empíricos, en los que se identificaron objetivos, herramientas tecnológicas y principales resultados obtenidos. Se valoró el nivel de análisis de tres aspectos: el aprendizaje colaborativo, la gestión de información y la formación para los medios digitales; este último se indetificó como el menos atendido. La discusión conceptual se integra con las evidencias de las experiencias revisadas a manera de marco referencial de las posibilidades educativas de la curación de contenidos. La revisión pone de manifiesto el gran potencial educativo de la curación de contenidos, lo que alienta a seguir explorándola desde diferentes miradas y contextos

  6. Ludificación y sus posibilidades en el entorno de blended learning: revisión documental

    Directory of Open Access Journals (Sweden)

    Ángel Torres-Toukoumidis

    2018-01-01

    Full Text Available La ludificación en el entorno de aprendizaje semipresencial constituye una innovación de alto impacto en las posibilidades de aprendizaje. Se considera que comparte aspectos con el blended learning, en relación con el aumento de la motivación y la optimización en la obtención de resultados respecto a una actividad para estimular el aprendizaje. En este sentido, este trabajo plantea un análisis de publicaciones en bases de datos internacionales en las que se aborda la cuestión de la ludificación en el entorno de blended learning. Para ello se realiza una revisión de literatura científica, aplicando la documentación como método para la sistematización. El estudio que se presenta analiza 34 aportaciones entre 2012 y 2017* indexadas en las bases de datos WOS y Scopus, utilizando una estrategia de búsqueda basada en cuatro criterios: público (destinatario, tópico, diseño metodológico y conclusiones principales. Los resultados demuestran que las publicaciones reseñadas se centran en estudiantes de educación superior, especialmente del ámbito de la ingeniería, exponen prototipos y modelos, y presentan diseños metodológicos en los que predomina el marco teórico-conceptual, seguido de estudios empírico cuantitativos. Se deduce, en consecuencia, entre otros aspectos, la necesidad de seguir impulsando la convergencia ente ludificación y blended learning, dado el efecto positivo que conlleva en relación con la motivación, retroalimentación y en la adquisición de competencias por parte de los estudiantes.

  7. Las posibilidades y peligros del pensamiento basado en imágenes en la resolución de problemas matemáticos

    OpenAIRE

    Presmeg, Normal

    1999-01-01

    El planteamiento de los problemas permitidos en la reflexión sobre algunas de las posibilidades y peligro del pensamiento vas a ver imágenes de matemáticas. Se introduce las definiciones de imaginería, de pensamiento basadas en imágenes de visualización, y se presentan a través de ejemplos diferentes tipos de imaginería visual.

  8. Posibilidades de Generación de Energía en base al Potencial Geotérmico de la Península de Santa Elena.

    Directory of Open Access Journals (Sweden)

    Hernán E. Poveda Z.

    2015-10-01

    En este estudio, proponemos la posibilidad de utilizar esta energía natural para transformarla en electricidad. Aprovechando las condiciones de algunos de los afloramientos de manantiales de agua caliente y volcanes de lodo que existen en la provincia. Para lo cual hemos propuesto al Instituto Austriaco de tecnología, su asesoría y asistencia para proponer un proyecto al ministerio de electrificación y energías renovables.

  9. POSIBILIDADES DE UTILIZACIÓN DE LA GEOLOCALIZACIÓN Y REALIDAD AUMENTADA EN EL ÁMBITO EDUCATIVO

    Directory of Open Access Journals (Sweden)

    Javier Fombona Cadavieco

    2017-01-01

    Full Text Available La reciente implantación de las tecnologías portátiles digitales en la socie - dad, y especialmente entre los jóvenes, supone un desafío para los docentes, y podría ser una oportunidad para obtener un mayor aprovechamiento acadé - mico. Este artículo presenta una investigación sobre el uso educativo de apli - caciones de Geolocalización y Realidad Aumentada con dispositivos digitales móviles en niveles de Enseñanza Secundaria, Bachillerato y Formación Profe - sional. Se trata de una investigación para averiguar si es posible emplear estos recursos en los dispositivos móviles del alumnado para obtener un beneficio y mejora educativa. El trabajo se inicia con una revisión de estos desarrollos tec - nológicos desde una dimensión formativa. A continuación se realiza un macro estudio descriptivo y cuantitativo entre 1832 alumnos en el que analizamos el tipo de dispositivos que poseen; para posteriormente analizar la opinión del profesorado sobre la funcionalidad y utilidad didáctica de estos desarrollos. Los resultados clarifican la tipología y penetración de los dispositivos entre los tres niveles educativos analizados, y los datos apuntan la posibilidad de imple - mentar estas tecnologías ya que sus equipos disponen de sistemas operativos avanzados y hardware GPS apropiado. Desde la perspectiva docente se pueden superar las reticencias a su uso con la incorporación inicial en tareas fuera del centro y en actividades no presenciales. Junto a las características de desloca - lización espacio/temporal propias del m-learning, surgen rasgos innovadores en la metodología educativa derivados de estrategias que impulsan las rela - ciones colaborativas, no competitivas. La Realidad Aumentada aparece como elemento con alto poder motivador en las tareas, abre puertas a la exploración autónoma, no lineal, de mundos virtuales que incorporan actualmente un ele - vado componente sorpresivo para el usuario. Por otro lado la

  10. Laser Technology.

    Science.gov (United States)

    Gauger, Robert

    1993-01-01

    Describes lasers and indicates that learning about laser technology and creating laser technology activities are among the teacher enhancement processes needed to strengthen technology education. (JOW)

  11. Posibilidades del método de elementos finitos y partículas (PFEM) en problemas de erosión de suelos granulares

    OpenAIRE

    Rodríguez Prat, Francisco

    2013-01-01

    El fenómeno de erosión es un tema de vital importancia en el ámbito de la ingeniería civil, especialmente en ingeniería de ríos. En este trabajo se analizan las posibilidades del método de elementos finitos y partículas (PFEM) para abordar este tipo de problemas. El PFEM es una variante del método de elementos finitos clásico (FEM); se ha empezado a utilizar principalmente para modelizar el movimiento de fluidos. El programa que se ha utilizado es el Pflow, desarrollado en C...

  12. ¿Agroindustria en la Amazonía? Posibilidades para el desarrollo inclusivo y sostenible de la palma aceitera en el Perú

    OpenAIRE

    2016-01-01

    En la discusión sobre las posibilidades de desarrollo del cultivo agroindustrial de la palma aceitera en la Amazonía peruana se plasman varios de los principales debates modernos sobre modelos de desarrollo rural ambientalmente sostenibles y socioeconómicamente inclusivos. La historia de la expansión de este sector y los diversos problemas que hoy enfrenta reflejan, además, muchas de las limitaciones institucionales del actual Estado peruano para definir su rol con claridad y un planeamiento ...

  13. Descripción y referencia: el lenguaje como posibilidad de veracidad. Un asunto de límites de sistemas-mundo y actos de habla

    Directory of Open Access Journals (Sweden)

    FRANCISCO LUIS GIRALDO GUTIÉRREZ

    2017-01-01

    Full Text Available En este artículo desarrollamos el concepto de lenguaje y de cómo él, como acción del hombre en el hombre, al hacerse presente a modo de representación y expresión, tiene la pretensión de validar aquello que conoce –el objeto– y la manera como lo conoce. De esta forma, partimos de concebir el lenguaje como un sistema, una semiótica social y una intención. Mediante el lenguaje y el acto comunicativo de la interlocución, el sujeto determina la veracidad/validez del hecho, la acción: actúa en el sistema y acorde con él, y establece el nivel de correspondencia de la idea –pensada o manifestada– y el objeto, como producto final de su capacidad de hacer y comunicar. Como tesis, planteamos que, independientemente del modo o modos en que se conjuguen los códigos lingüísticos, lo que importa es su posibilidad de veracidad. De igual modo, esos niveles y posibilidades están limitados o ampliados por los sistemas-mundo de los sujetos intervinientes en el acto de habla.

  14. RECIÉN NACIDO PORTADOR DE CARDIOPATÍA CONGÉNITA COMPLEJA. ANÁLISIS DE RIESGO, TOMA DE DECISIONES Y NUEVAS POSIBILIDADES TERAPÉUTICAS

    Directory of Open Access Journals (Sweden)

    Dr. Luis Cárdenas

    2016-07-01

    Full Text Available Se presenta en este artículo de revisión, un análisis de los factores a considerar en la toma de decisiones de manejo respecto a un grupo de pacientes portadores de cardiopatías congénitas complejas de muy alto riesgo, generalmente asociadas a comorbilidades y condiciones agravantes. Basándose en la experiencia de los autores, revisión de la literatura y casos clínicos ilustrativos, se sugieren posibilidades terapéuticas iniciales, poniendo énfasis en el análisis estrictamente caso a caso y las características que posea el centro de salud. Se proponen además nuevas posibilidades de tratamiento para el extremo del espectro en este grupo de recién nacidos, mostrando que una estrategia híbrida, quirúrgica-intervencional, es posible y segura para pacientes con bajo peso de nacimiento, anatomías extremadamente complejas o con comorbilidad asociada de alto riesgo. Para lograr éxito en este abordaje, es necesario que grupos multidisciplinarios se involucren en todo el proceso de diagnóstico y tratamiento.

  15. Género y Sexualidad en los Márgenes: entre la sujeción identitaria y la búsqueda de espacios de posibilidad

    Directory of Open Access Journals (Sweden)

    David Berná (entrevistado

    2013-06-01

    Full Text Available En esta entrevista abordamos, en primer lugar, el cambio de paradigma que supone la emergencia del campo teórico posfeminista y las implicaciones que ello tiene de cara a la emancipación social, preguntándonos por lga posibilidad de luchas no articuladas en base a identidad. Para después, con la intención de confrontar desde un lenguaje de ejemplos la problemática interseccional de la identidad de género, dirigir la mirada desde una perspectiva múltiple hacia realidades y vivencias más cercanas, cuestiones como la discriminación del colectivo transmaricabollo en Centros de Internamiento de Extranjeros (CIEs o la homosexualidad en gitanos y gitanas.

  16. La gallina de los huevos de oro de nuevo está en peligro. Imágenes, posibilidades y viabilidades de la inteligencia colectiva

    Directory of Open Access Journals (Sweden)

    Jaime Alejandro Rodríguez Ruiz

    2007-01-01

    Full Text Available Dos proyectos wiki de ficción colaborativa, uno que fracasa y otro que se desarrolla con éxito, sirven como pretexto en este artículo para desplegar una reflexión sobre los nuevos modos de pensamiento y de vínculo social, favorecidos hoy por las nuevas tecnologías de la información y la comunicación: el proyecto de la inteligencia colectiva. Cuatro autores fundamentan esta reflexión: Pierre Lévy, Derrick de Kerckhove, Howard Rheingold y David Casacuberta. Después de mostrar las posibilidades del ejercicio de la inteligencia colectiva, el artículo concluye al afirmar que el espacio del conocimiento se constituye, irreversiblemente, en un nuevo espacio antropológico: el de la inteligencia colectiva, al que todos estamos llamados a construir.

  17. Posibilidades de promover una enculturación matemática en la infancia a través del arte

    OpenAIRE

    Ceberio, Ibon

    2014-01-01

    Atendiendo a los puentes existentes entre arte y matemáticas, mediante este ensayo se profundiza en la posibilidad de emplear el arte para el aprendizaje matemático. Así, partiendo de los preceptos de la antigua Grecia en cuanto a la educación, se opta por una perspectiva cultural de la educación matemática, analizando cómo se forma esta tecnología simbólica, cuáles son los valores que organizan nuestra cultura matemática concreta, cómo ha de ser la enculturación de los niños, la cabida del a...

  18. Rancière y la posibilidad de un «acontecimiento» político en la educación

    Directory of Open Access Journals (Sweden)

    Gastón Beraldi

    2009-01-01

    Full Text Available En este artículo se intenta, por un lado, pensar la posibilidad de ver a Rancière como un «maestro de la sospecha» en cuanto a la crítica que le realiza a la pedagogía explicacionista, y por otro lado, analizar si la propuesta de Rancière/ Jacotot puede constituirse en un acontecimiento político en la educación. La condición para ello radicará en que la tesis de Rancière pueda transformarse en una irrupción en los términos de Badiou, y que pueda ser caracterizado entonces como un acontecimiento político en la educación al punto de hacerla entrar en crisis.

  19. Mejorar la escuela inclusiva: un análisis en torno a la consciencias explicativas de la diversidad y las posibilidades subjetivas de la cultura escolar

    Directory of Open Access Journals (Sweden)

    Aldo Ariel Ocampo González

    2014-02-01

    Full Text Available Esta comunicación, reflexiona sobre los desafíos y las oportunidades, que enfrenta la escuela de educación regular, ante la legitimación de la diversidad, al interior de sus estructuras y consciencias explicativas. Se propone un marco comprensivo para la mejora de la calidad en la escuela inclusiva, mediante la comprensión de sus procesos institucionales y la construcción de justicia social, en torno a la diversidad, como factor inherente a la experiencia socioeducativa. El autor analiza las posibilidades objetivas y subjetivas, asociadas a la construcción de escuelas inclusivas de calidad, desde sus dimensiones institucionales, organizacionales y ecológico-contextuales. Por lo que, constantemente, se pregunta, acerca ¿de qué manera la escuela puede constituirse como un espacio de real inclusión para todos sus estudiantes?

  20. Diseño de una instalación fotovoltaica para una vivienda aislada con posibilidad de compra-venta a red

    OpenAIRE

    Subiza Betelu, Sara

    2014-01-01

    Este proyecto fin de carrera tiene como objetivo el diseño de una instalación fotovoltaica para una vivienda aislada con conexión a red, y la evaluación de la viabilidad tanto técnica como económica de la instalación. Esta instalación estará situada en el tejado de una vivienda aislada, que se encuentra en el término municipal de Ariz (Navarra). El proyecto tiene como finalidad la autonomía energética de dicha vivienda y la posibilidad de compra-venta a red de la energía eléctrica. Se a...

  1. Diseño de una prótesis liviana de cadera con la posibilidad de incorporar medicación

    OpenAIRE

    Losa Zapico, Paula

    2018-01-01

    En el presente Trabajo de Fin de Grado se va a llevar a cabo el diseño de una prótesis liviana de cadera que pueda sustituir la articulación y aporte la posibilidad de introducir a través de ella medicamentos en el cuerpo. Así será posible administrar los fármacos necesarios en el postoperatorio de forma directa en la articulación, con los beneficios de que se necesitará menor dosis y su acción será más eficaz. Con esto se mejorará la comodidad del paciente y la adaptación del cuerpo al di...

  2. La Posibilidad de Revisión del Mérito del Acto Administrativo Discrecional, en Razón de los Principios Constitucionales

    Directory of Open Access Journals (Sweden)

    Juventino de Castro Aguado

    2015-12-01

    Full Text Available Este artículo tiene como objetivo examinar la posibilidad de revisar los méritos de los actos administrativos discrecionales por el Poder Judicial con los principios constitucionales. Estos actos tienen elementos no regrados en el sistema legal, que dependen de la sentencia de la conveniencia y oportunidad del administrador público. Estos elementos se llaman méritos del acto administrativo. Antes, guardián de la libertad completa, ya que no se rige por la ley, que actualmente sufre más restricciones, la necesidad de respetar los principios del derecho, especialmente los que figuran en la Constitución, en el artículo 37. En consecuencia, aumenta la posibilidad de control judicial. El poder judicial tendrá un Consejo de control de la legalidad en su conjunto, incluyendo el mérito administrativo, si es provocado correctamente por el legítimo y respetando los límites impuestos por la propia Constitución. En un Estado democrático de derecho, donde la revisión judicial del acto administrativo es necesario para que  sea  posible  el  fiel  cumplimiento  de  los  objetivos  constitucionales  prestados  a  la República.  Para  el  desarrollo  de  la  investigación  se  utilizó  la  metodología  analítico- deductiva,  haciendo  uso  de  libros,  revistas,  artículos  publicados  en  los  sitios  web,  la legislación ordinaria, la Constitución y la Jurisprudencia.

  3. Capacidades epistemológicas foucaultianas: la posibilidad de los dispositivos tecnocientíficos Foucaultian epistemological capacities: the posibility of the technoscientific dispositifs

    Directory of Open Access Journals (Sweden)

    Antonio Arellano Hernández

    2007-01-01

    Full Text Available La noción de Red había sido puesta en escena como alternativa conceptual-metodológica para explicar la organización de la investigación; No obstante, a fuerza de acuñaciones nomológicas parecen erosionada sus posibilidades epistemológicas. En este trabajo buscamos fuentes de inspiración en la noción de dispositivo de Michel Foucault, para continuar el estudio de la ciencia y la tecnología de manera que se mantenga una posición metodológica que permita avanzar en el conocimiento de la investigación científico-técnica. Para tal efecto, abordamos el uso descriptivo de la noción de red, el debate por su significación nomológica y metodológica y, finalmente, la discusión sobre las posibilidades epistemológicas de la noción focultiana de dispositivo.Network notion emerged as an alternative methodological concept to explain the research organization. However, after several different nomological uses, its epistemological possibilities seem eroded. In this work we look for inspiration in Michel Foucault's notion of dispositive to continue the study of science and technology within a methodological position allowing to advance the knowledge of scientific and technical research. In that intent, we discuss the descriptive use of the network notion, the debate about its nomological and methodological signification and, al last, the epistemological possibilities of Foucault's notion of dispositive.

  4. The Newest Laser Processing

    International Nuclear Information System (INIS)

    Lee, Baek Yeon

    2007-01-01

    This book mentions laser processing with laser principle, laser history, laser beam property, laser kinds, foundation of laser processing such as laser oscillation, characteristic of laser processing, laser for processing and its characteristic, processing of laser hole including conception of processing of laser hole and each material, and hole processing of metal material, cut of laser, reality of cut, laser welding, laser surface hardening, application case of special processing and safety measurement of laser.

  5. Del mosaico al googlegrama: posibilidades creativas de la interacción imagen y texto / From mosaic to Googlegram: creative possibilities of the

    Directory of Open Access Journals (Sweden)

    Iria Barcia Sánchez

    2009-06-01

    Full Text Available Resumen: El artículo explora las múltiples interrelaciones que se establecen entre la imagen y el texto, centrándose por una parte en las diversas posibilidades que ofrece la complementariedad de ambos elementos, y por otra parte, en la diferente intencionalidad u objetivos comunicativos a que se presta el empleo de dicha combinación del elemento verbal y el iconográfico. Así, se comentan diferentes ejemplos que ponen de relieve la mayor o menor complejidad de dicha interacción imagen-texto, desde la sencillez del mosaico romano a la osadía creativa de los Googlegramas de Joan Fontcuberta de la era de Internet en que vivimos, destacando el hecho fundamental de que la imagen con frecuencia añade un elemento connotativo del que carece el texto por sí solo. En cuanto a la intencionalidad, el artículo incide en la constante exploración de esta asociación de elementos que hace el mundo de la publicidad, pero también en otras posibilidades persuasivas e incluso críticas, reflejadas especialmente en los medios de comunicación, y sin olvidar tampoco su indudable interés didáctico y las grandes oportunidades que en este sentido ofrecen las herramientas informáticas.Summary: The article examines the wide relations which are set between image and text, focusing, on the one hand, in the several possibilities offered by the combination of both elements, and on the other hand in the different communicative objectives which can be reached throughout the use of this combination. Thus, several examples are mentioned, revealing different degrees of complexity in the image-text interaction, from the simplicity of the Roman mosaic to the audacity of Joan Fontcuberta’s Googlegrams in today’s Internet age, emphasizing the main fact that image often adds a connotative element which the text lacks by itself. Regarding objectives, the article focuses on the number of samples of this combination of elements that the world of advertising shows, but

  6. Laser Therapy

    Science.gov (United States)

    ... for Every Season How to Choose the Best Skin Care Products In This Section Dermatologic Surgery What is dermatologic ... for Every Season How to Choose the Best Skin Care Products Laser Resurfacing Uses for Laser Resurfacing Learn more ...

  7. Agenciación humana en la teoría cognitivo social: Definición y posibilidades de aplicación

    Directory of Open Access Journals (Sweden)

    Alonso Tejada Zabaleta

    2005-01-01

    Full Text Available La agenciación humana es la capacidad de ejercitar el control sobre nuestro propio funcionamiento y sobre los eventos que afectan nuestra vida (Bandura, 2001. El concepto aparece como resultado del desarrollo del Análisis Conductual Cognoscitivo y específicamente de la teoría Cognitivo Social de Bandura y sus colaboradores; y es un desglosamiento de los conceptos iniciales de autocontrol y autodirección y luego del de autoeficacia. La agenciación supone ser una estrategia de cambio para que los individuos puedan generar modificaciones y transformaciones de sí mismos y de su ambiente, por lo tanto, implica un proceso y un procedimiento sistemático para determinarse, desarrollarse, retroalimentarse y modificarse.El presente trabajo presenta la definición y contextualización de la agenciación humana, propone un modelo estratégico de cambio a partir del establecimiento y desarrollo de competencias de agenciación, y analiza y evalúa las posibilidades de aplicación en contextos sociales

  8. Posibilidades de la aplicación de la Arqueología de la Arquitectura en Santa Eulalia de Bóveda (Lugo

    Directory of Open Access Journals (Sweden)

    Vidal Caeiro, Lorena

    2003-12-01

    Full Text Available This study attempts to show the possibilities offered by the application of Archaeology of Architecture in the Lugo building of Santa Eulalia de Bóveda. The present synthesis shows what we have identified as different architectonic stages which the building has seen since its construction. Each element has been isolated, whether decorative or architectonic elements present in the modern day construction. These are organized into five possible construction stages according to what has happened to the building from the Roman era to contemporary alterations.El trabajo que presentamos pretende mostrar las posibilidades que ofrece la aplicación de la Arqueología de la Arquitectura en el edificio lucense de Santa Eulalia de Bóveda. La presente síntesis muestra lo que hemos identificado como las diferentes etapas arquitectónicas por las que ha pasado el edificio desde su construcción. Se ha aislado cada uno de los elementos, tanto decorativos como arquitectónicos presentes en la actual construcción, organizándolos en las cinco posibles etapas constructivas por las que ha pasado el edificio, desde la etapa romana hasta la reforma contemporánea.

  9. El portafolio docente a escrutinio: sus posibilidades y restricciones en la formación y evaluación del profesorado.

    Directory of Open Access Journals (Sweden)

    Frida Díaz Barriga Arceo

    2010-07-01

    Full Text Available A pesar del gran entusiasmo y amplia difusión que han despertado los portafolios como recurso innovador en la evaluación y formación del profesorado, debe realizarse un análisis de su sentido y alcances, para evitar su empleo indiscriminado y poco crítico. En este artículo se revisa el surgimiento y supuestos educativos de los portafolios docentes, así como algunos estudios que dan cuenta de su potencialidad como recurso de evaluación auténtica y reflexión sobre la propia identidad y práctica educativa de los docentes en formación. Asimismo, se revisan una serie de críticas y notas precautorias respecto a su empleo, sobre todo cuando se pretende su aplicación como instrumento estandarizado a gran escala. Se concluye que su mayor potencial reside en promover la autoevaluación reflexiva de los profesores y en la posibilidad de impulsar un cambio en la cultura de la evaluación en las instituciones educativas. Al mismo tiempo, el gran riesgo consiste en la proliferación de una mirada exclusivamente técnica y sesgada, centrada en los instrumentos de calificación, con poco fundamento teórico e investigación empírica.

  10. El diario: la escritura autobiográfica en su dimensión sociocultural y sus posibilidades cognoscitivas y creativas

    Directory of Open Access Journals (Sweden)

    Angélica González Otero

    2017-01-01

    Full Text Available La escritura diarística está inmersa en la vida personal y social de nuestra cultura como una herramienta de análisis social y un ejercicio de escritura personal. Este artículo de reflexión pretende exponer y describir algunos ejemplos de escrituras diaristas en distintos ámbitos y contextos que van desde la creación artística hasta los procesos de formación educativa; y de esta manera, intentar vislumbrar las potencialidades y aciertos que trae la escritura autobiográfica para los espacios subjetivos, cognitivos y creativos de los individuos. Palabras clave: diario, autobiografía, subjetividad, aprendizaje, creación, educación. Citar: González Otero, A. (enero-junio de 2017. El diario: La escritura autobio - gráfica en su dimensión sociocultural y sus posibilidades cognoscitivas y creativas. La Palabra , (30, 151 – 167. doi: https://doi.org/10.19053/01218530.n30.2017.6961 Angélica González Otero Magíster en Literatura de la Universidad Javeriana de Bogotá. Docente investigadora Licenciatura en Lingüística y Literatura de la Universidad La Gran Colombia. a

  11. Estado Y Prospectiva De Las Posibilidades De Adaptación Al Cambio Climático En La Región Atlántica Colombiana

    Directory of Open Access Journals (Sweden)

    Leonardo Fabio P

    2014-01-01

    El artículo plantea el abordaje conceptual sobre la adaptación al cambio climático en los contextos internacional, regional y local; se analizan e interpretan las acciones realizadas en la región Costa Atlántica, para determinar la capacidad de adaptación que permita afrontar las situaciones derivadas de dicho cambio y se indagan las posibilidades en materia de adaptación.   Abstract Climate change is a reality facing humanity, a subject of the present and the future, is not a prediction, it is perhaps the greatest challenge that mankind is facing in its efforts to continue living in this world, without distinction between countries poor nor rich, nor between social classes. Given this reality, the most effective adaptation to counteract the effects of this phenomenon, which requires the development of institutional and social capabilities that enable joint efforts of government, as social and economic actors, arises. The article presents the conceptual approach on adaptation to climate change at the international, regional and local contexts; analyzed and interpreted the actions in the Atlantic Coast region, to determine the adaptability which to cope with situations arising from the change and investigate possibilities for adaptation.

  12. Odontología para bebés: una posibilidad práctica de promoción de salud bucal

    Directory of Open Access Journals (Sweden)

    Marina Moscardini Vilela

    2017-07-01

    Full Text Available Objetivo. Revisar la literatura sobre la filosofía en Odontología para Bebés. Síntesis de datos. A pesar de que la promoción de la salud es muy practicada en todas las áreas de la salud, la odontología se caracteriza por restar importancia a la prevención de enfermedades bucales y a los tratamientos preventivos, cuando estos son realizados, ya los dientes deciduos se encuentran altamente comprometidos por la caries dental. Los resultados alcanzados a través de la enseñanza de tratamiento odontológico a bebés, en diferentes partes del mundo, tienen un futuro promisorio, ya que enfatiza las particularidades de su crecimiento y desarrollo infantil, considera al bebé como un todo, y no solamente desde el punto de vista de salud bucal. Conclusiones. La buena práctica de la odontología para bebés brinda la posibilidad de fomentar la salud y prevenir la enfermedad, de una forma muy simple, eficaz y de bajo costo.

  13. Lasers technology

    International Nuclear Information System (INIS)

    2014-01-01

    The Laser Technology Program of IPEN is developed by the Center for Lasers and Applications (CLA) and is committed to the development of new lasers based on the research of new optical materials and new resonator technologies. Laser applications and research occur within several areas such as Nuclear, Medicine, Dentistry, Industry, Environment and Advanced Research. Additional goals of the Program are human resource development and innovation, in association with Brazilian Universities and commercial partners

  14. YCOB lasers

    International Nuclear Information System (INIS)

    Richardson, Martin; Hammons, Dennis; Eichenholz, Jason; Chai, Bruce; Ye, Qing; Jang, Won; Shah, Lawrence

    1999-01-01

    We review new developments with a new laser host material, YCa 4 O(BO 3 ) 3 or YCOB. Lasers based on this host material will open new opportunities for the development of compact, high-power, frequency-agile visible and near IR laser sources, as well as sources for ultrashort pulses. Efficient diode-pumped laser action with both Nd-doped and Yb-doped YCOB has already been demonstrated. Moreover, since these materials are biaxial, and have high nonlinear optical coefficients, they have become the first laser materials available as efficient self-frequency-doubled lasers, capable of providing tunable laser emission in several regions of the visible spectrum. Self-frequency doubling eliminates the need for inclusion of a nonlinear optical element within or external to the laser resonator. These laser materials possess excellent thermal and optical properties, have high laser-damage thresholds, and can be grown to large sizes. In addition they are non-hygroscopic. They therefore possess all the characteristics necessary for laser materials required in rugged, compact systems. Here we summarize the rapid progress made in the development of this new class of lasers, and review their potential for a number of applications. (author)

  15. Laser sampling

    International Nuclear Information System (INIS)

    Gorbatenko, A A; Revina, E I

    2015-01-01

    The review is devoted to the major advances in laser sampling. The advantages and drawbacks of the technique are considered. Specific features of combinations of laser sampling with various instrumental analytical methods, primarily inductively coupled plasma mass spectrometry, are discussed. Examples of practical implementation of hybrid methods involving laser sampling as well as corresponding analytical characteristics are presented. The bibliography includes 78 references

  16. HF laser

    International Nuclear Information System (INIS)

    Suzuki, Kazuya; Iwasaki, Matae

    1977-01-01

    A review is made of the research and development of HF chemical laser and its related work. Many gaseous compounds are used as laser media successfully; reaction kinetics and technological problems are described. The hybrid chemical laser of HF-CO 2 system and the topics related to the isotope separation are also included. (auth.)

  17. Teacher Teams in Compulsory Secondary Education: Possibilities and Uncertainties Equipos docentes en la Enseñanza Secundaria Obligatoria: posibilidades e incertidumbres.

    Directory of Open Access Journals (Sweden)

    Mª Teresa González González

    2007-10-01

    Full Text Available This paper is about the constitution of teacher teams in the Educación Secundaria, something proposed in the Ley Orgánica de Educación (LOE, 2006. First, a discussion of the disadvantages of organizing high schools by academic departments is presented, namely, the tendency of teachers to communicate mainly with those colleagues working in the same curricular area, the difficulties involved in the development of curricular projects that translate into globally coherent school experiences meaningful and relevant for the students, and the repercussions of such structures on the caring and support for students. Against this background, it is suggested that one of the alternatives to counteract the effects of departmentalization entails the creation of teacher teams. The new possibilities of coordination offered by teams are then commented, as they are seen as appropriate instruments to articulate the work and reflection of their members on cross curricular issues. Finally, some uncertainties and complexities of this new structure are discussed, namely, the possibility of it being applied only at a formal level, the difficulties involved in the coexistence of teams and departments, or the risk of overlooking the ”instituto” as a globally oriented educational institution. Este artículo plantea algunas reflexiones sobre la constitución de equipos, la colaboración y el trabajo conjunto de los profesores que imparten clase en un mismo grupo de alumnos en la Educación Secundaria Obligatoria (ESO'por tanto en los institutos de educación secundaria', una posibilidad contemplada en la recientemente promulgada Ley Orgánica de Educación (LOE, 2006. En primer lugar, se realizan algunas consideraciones acerca de los puntos débiles de la estructura organizativa departamentalizada característica de los institutos. Se menciona, así, la tendencia del profesorado a relacionarse básicamente con colegas que trabajan en una misma

  18. La posibilidad de autor femenino en la violencia doméstica/Possibility of the woman being active subject of the domestic violence

    Directory of Open Access Journals (Sweden)

    Héctor Julián Cristóbal Luengo (España

    2014-08-01

    Full Text Available Las cotas de delincuencia femenina han sido, a lo largo de la historia, mucho menores que las masculinas. Resulta sencillo acceder a estudios sobre la delincuencia masculina, siendo, sin embargo, más complicado encontrar investigaciones sobre mujeres delincuentes, y más, aún, desde la perspectiva de género. Ante ello, surge la dificultad de discernir si los factores de riesgo/protección que influyen en la conducta antijurídica de los hombres van a ser los mismos que inciden en la delincuencia femenina. Es por ello interesante una reflexión sobre la posibilidad de que sea la mujer el sujeto activo de la delincuencia que tiene lugar en el ámbito familiar, hecho, que si bien, ajeno a la intencionalidad de la última reforma del Código Penal en la materia –Ley Orgánica 1/2004, de violencia de género-, se encontraba ya prevista en el articulado del Código, donde el legislador nunca desdeñó la posibilidad de que todas las conductas relativas al maltrato pudieran tener un autor femenino. Seguimos manteniendo una sociedad desigual en la que, si bien en un camino descendente, la mujer sigue sometida al hombre, a lo que colabora un conjunto de estereotipos y de roles que sitúan a la mujer en el epicentro de un mayor control social y de la tradicional dominación masculina. Esta desigualdad de género se traslada incluso al interior de las cárceles, espacios que no dejan de ser un reflejo de la sociedad y en la que estas desigualdades, incluso se acrecientan. The proportions of the female delinquency had always been, throughout history, of a lesser extent than the masculine. It is easy to have access to studies about masculine delinquency; however, it is far more complicated to find investigations about female delinquents, and even more, from the gender perspective. Considering that, appears the difficulty of discerning if the risk/protection factors that have influence in the illegal behavior of the men are the same that influence in the

  19. El movimiento de la existencia: posibilidades y límites de la descripción fenomenológica de la corporeidad

    Directory of Open Access Journals (Sweden)

    César Augusto Delgado Lombana

    2012-03-01

    Full Text Available En el presente texto, se pretende evidenciar los alcances de la propuesta de una fenomenología de la percepción desde Maurice Merleau Ponty. En el artículo se desarrollan dos argumentos: el objetivo de Merleau-Ponty quien se opone a las teorías psicologistas que han reducido la percepción a la sensación pura, es decir, a la aprehensión de datos sensitivos aislados. Por el contrario, deseamos evidenciar que Merleau-Ponty comprende la percepción como la interpretación de un horizonte de significación (perspectiva que permite la correlación entre sujeto y objeto. En sentido estricto, percibir es la posibilidad de comprender que el objeto se da en ámbitos de significación que permiten la constitución entre sujeto y objeto. Esta tesis tendrá por consecuencia más próxima que la escisión sujeto objeto se supere y se vea la doble faz de la percepción: la perspectiva (estructura objeto-horizonte, la cual me permite experienciar objetos no como meros datos aislados, sino como horizonte, es decir, como ámbitos de significación. En segundo lugar, será necesario abordar las críticas de Merleau-Ponty a las teorías sobre el cuerpo que, en su aspecto más radical, han conducido a la cosificación del mismo, es decir, a la reducción de la corporalidad a una cosa más entre las cosas.

  20. Social capital and political culture in Brazil: prospectives and constrains Capital social y cultura política en brasil: posibilidades y límites

    Directory of Open Access Journals (Sweden)

    Cesar Marcelo BAQUERO JACOME

    2010-10-01

    Full Text Available This article examines the relationship between political culture and social capital in Brazil. It emphasizes the importance of constructing a political system founded in the interpersonal or reciprocal trust, as well as the confidence in the political institutions. After examining the main controversies about the definition of social capital, this article defends the idea of reterritorializing this concept, giving a strategic value insofar as the instrumental dimension is concerned, which is, the empowerment of the citizens so as to help to construct and institutionalize a participant political culture. After examining surveys carried out in Porto Alegre, Brazil, the main conclusion is that the levels of social capital in this city, and probably extensive to the country, are very low compromising, in the short run, the possibility of gerating a critical and participative citizenship.El presente artículo examina la relación entre cultura política y capital social en Brasil. Se enfatiza la importancia de construir un sistema político fundamentado en la confianza recíproca o interpersonal así como la confianza con relación a las instituciones políticas. Después de examinar las controversias sobre la conceptualización de capital social, este trabajo defiende la idea de la reterritorialización de ese concepto, valorizando su dimensión instrumental, es decir, el empoderamiento de los ciudadanos objetivando el desarrollo e institucionalización de una cultura política participativa. Tras desarrollar un análisis de encuestas llevadas a cabo en Porto Alegre, Brasil, se llega a la conclusión de que los niveles de capital social en el país son muy bajos comprometiendo, a corto plazo la posibilidad de generar una ciudadanía crítica y participativa.

  1. POSIBILIDADES E IMPOSIBILIDADES DE LA INCORPORACIÓN DE LA EDUCACIÓN AMBIENTAL EN LA ESCUELA: PROPUESTA DE ESTRATEGIA EVALUATIVA

    Directory of Open Access Journals (Sweden)

    CAROLINA VARGAS NIÑO

    2013-06-01

    Full Text Available El propósito de la investigación fue formular una estrategia para evaluar los alcances de la incorporación de la propuesta de transversalidad de la educación ambiental (EA en el currículo de la escuela, a la luz de las posibilidades o la imposibilidades que los maestros rescatan en su quehacer y ser, dentro de sus realidades escolares, con el objetivo de contrastar los hallazgos, a través de categorías conceptuales, metodológicos y operativos desde la Política Nacional de Educación Ambiental (PNEA, como panorama de lectura y comprensión de una realidad educativa queresponde a la normatividad del sistema gubernamental nacional e internacional, al aproximarse a la resolución de las problemáticas ambientales y al alcance del desarrollo sostenible. La indagación se proyecta a la comprensión de las nociones que tienen los maestros en ejercicio de la forma como se está llevando a cabo la incorporación de la EA en sus instituciones, mediante la técnica de recolección de información de grupo focal. Se llegó así a concluir que el saber ambiental dentro de la escuela, se evidencia como aquel que está orientado desde la necesidad por el “hacer” por un “activismo” acelerado, que intenta más allá de la comprensión de las dinámicas ambientales, minimizar el desconocimiento del daño ambiental y propender por un estado de conservación de los recursos, en donde se expone la relación con el concepto de ambiente, como recurso para utilizar y proteger.

  2. Nuevas tintas digitales para la obtención de innovadores efectos cerámicos con los que generar nuevas posibilidades y tendencias de futuro

    Directory of Open Access Journals (Sweden)

    Torrecid, Grupo

    2012-04-01

    Full Text Available This technical note contains the most significant aspects of the work “New digital inks for the production of innovative ceramic effects which generate new possibilities and future trends” in which the Group Torrecid won the “Alfa de Oro 2012” given by the Spanish Society of Ceramics and Glass. To achieve the stated objectives to work in different fields of activity for each specific ink has been necessary, comprising, among other, aspects such as the development of special frits, selecting the most suitable solvents or optimizing the compositions to ensure that the inks have appropriate behaviour in the printing process and met all the requirements of stability and quality that the ceramic industry demand.

    En la presente nota técnica se recoge los aspectos más significativos del trabajo “Nuevas tintas digitales para la obtención de innovadores efectos cerámicos con los que generar nuevas posibilidades y tendencias de futuro” por el que el Grupo Torrecid obtuvo el Premio Alfa de Oro 2012 otorgado por la Sociedad Española de Cerámica y Vidrio. Para conseguir los objetivos planteados ha sido necesario trabajar en diferentes campos de actuación para cada tinta en concreto, abarcando, entre otros, aspectos como el desarrollo de fritas especiales, la selección de los disolventes más adecuados o la optimización de las composiciones para conseguir que las tintas tuvieran un comportamiento adecuado en el proceso de impresión y cumplieran todos los requisitos de estabilidad y calidad que el sector cerámico demanda.

  3. Laser fusion

    International Nuclear Information System (INIS)

    Eliezer, S.

    1982-02-01

    In this paper, the physics of laser fusion is described on an elementary level. The irradiated matter consists of a dense inner core surrounded by a less dense plasma corona. The laser radiation is mainly absorbed in the outer periphery of the plasma. The absorbed energy is transported inward to the ablation surface where plasma flow is created. Due to this plasma flow, a sequence of inward going shock waves and heat waves are created, resulting in the compression and heating of the core to high density and temperature. The interaction physics between laser and matter leading to thermonuclear burn is summarized by the following sequence of events: Laser absorption → Energy transport → Compression → Nuclear Fusion. This scenario is shown in particular for a Nd:laser with a wavelength of 1 μm. The wavelength scaling of the physical processes is also discussed. In addition to the laser-plasma physics, the Nd high power pulsed laser is described. We give a very brief description of the oscillator, the amplifiers, the spatial filters, the isolators and the diagnostics involved. Last, but not least, the concept of reactors for laser fusion and the necessary laser system are discussed. (author)

  4. Biocavity Lasers

    Energy Technology Data Exchange (ETDEWEB)

    Gourley, P.L.; Gourley, M.F.

    2000-10-05

    Laser technology has advanced dramatically and is an integral part of today's healthcare delivery system. Lasers are used in the laboratory analysis of human blood samples and serve as surgical tools that kill, burn or cut tissue. Recent semiconductor microtechnology has reduced the size o f a laser to the size of a biological cell or even a virus particle. By integrating these ultra small lasers with biological systems, it is possible to create micro-electrical mechanical systems that may revolutionize health care delivery.

  5. High power lasers & systems

    OpenAIRE

    Chatwin, Chris; Young, Rupert; Birch, Philip

    2015-01-01

    Some laser history;\\ud Airborne Laser Testbed & Chemical Oxygen Iodine Laser (COIL);\\ud Laser modes and beam propagation;\\ud Fibre lasers and applications;\\ud US Navy Laser system – NRL 33kW fibre laser;\\ud Lockheed Martin 30kW fibre laser;\\ud Conclusions

  6. Posibilidades sobre el uso de residuos de la industria del acero en la eliminación de metales de efluentes líquidos

    Directory of Open Access Journals (Sweden)

    Martín, M. I.

    2004-10-01

    Full Text Available A study is made of the removal of metals present in aqueous effluents using a residue of the steelmaking industry denominated rolling mill scale. Mill scale can be considered a cheap material for the removal of toxic metals due to its high content in iron oxides and metallic iron. A study of the removal of Cd+2, Zn+2, Pb+2 y Cu+2 ions from aqueous solutions was made, studying several variables that affect the process. The removal of cadmium, zinc and lead corresponding to a superficial adsorption process, was evaluated using the theories of Langmuir and Freundlich. The removal of copper occurs through a process of oxidation-reduction or cementation (Cu+2/Fe0. The possibilities of desorption were studied too.

    Se estudia la eliminación de metales presentes en efluentes acuosos empleando un residuo de la industria del acero denominado cascarilla de laminación. La cascarilla se puede considerar como un material barato para la eliminación de metales tóxicos por su alto contenido en óxidos de hierro y hierro metálico. Se ha realizado un estudio de la eliminación de los iones Cd+2, Zn+2, Pb+2 y Cu+2 contenidos en soluciones acuosas, estudiándose diversas variables que afectan al proceso. La eliminación de cadmio, cinc y plomo correspondiente a un proceso de adsorción superficial, se ha evaluado aplicando las teorías de Langmuir y Freundlich. La eliminación de cobre ocurre por un proceso de oxidación-reducción o cementación (Cu+2/Fe0. Se han ensayado, también, las posibilidades de desorción.

  7. Estado actual y posibilidades futuras de la Psicología en cuatro paises del Caribe: Puerto Rico, Cuba, República Dominicana y Haití

    Directory of Open Access Journals (Sweden)

    Blanca Ortiz-Torres

    2013-01-01

    Full Text Available Actualmente la formación de Psicólogos/as enfrenta retos serios en muchos de los países del Caribe y América Latina. Entre estos me interesa destacar: el debate sobre educación pública vs. educación privada, el aparente excedente de profesionales de la Psicología en algunos de nuestros países y la contracción y/o privatización de programas gubernamentales que tiene como consecuencia, el desplazamiento de Psicólogos/as al sector privado o a actividades profesionales desvinculadas de la Psicología. Debo aclarar, estos no son meros “debates”, se trata más bien de la aprobación e implantación de políticas, que ya inciden sobre el acceso de determinados sectores a la educación de post-grado en Psicología y sobre las posibilidades de inserción en el mundo laboral de egresados de programas de post-grado, así como de programas de licenciatura. Veamos brevemente cuál es el estado actual, no sin antes sugerir revisar la edición especial de la Revista Interamericana de Psicología publicada en el año 2000 y editada por la Dra. Ana Isabel Álvarez en la que se discute y analiza la historia de la Psicología en el Caribe. Esa edición representa un trabajo valiosísimo para nuestra disciplina y es fundamental para entender el presente de la misma. Además debo advertir que en este trabajo sólo presentaré la situación en cuatro países: Puerto Rico, Cuba, República Dominicana y Haití, ya que son los países en los que sostengo vínculos profesionales, por lo que conozco por experiencia directa lo que en ellos ocurre en términos de la disciplina.

  8. Laser Dyes

    Indian Academy of Sciences (India)

    amplification or generation of coherent light waves in the UV,. VIS, and near IR region. .... ciency in most flashlamp pumped dye lasers. It is used as reference dye .... have led to superior laser dyes with increased photostabilities. For instance ...

  9. Laser spectroscopy

    CERN Document Server

    Demtröder, Wolfgang

    2008-01-01

    Keeping abreast of the latest techniques and applications, this new edition of the standard reference and graduate text on laser spectroscopy has been completely revised and expanded. While the general concept is unchanged, the new edition features a broad array of new material, e.g., frequency doubling in external cavities, reliable cw-parametric oscillators, tunable narrow-band UV sources, more sensitive detection techniques, tunable femtosecond and sub-femtosecond lasers (X-ray region and the attosecond range), control of atomic and molecular excitations, frequency combs able to synchronize independent femtosecond lasers, coherent matter waves, and still more applications in chemical analysis, medical diagnostics, and engineering.

  10. Laser spectroscopy

    CERN Document Server

    Demtröder, Wolfgang

    Keeping abreast of the latest techniques and applications, this new edition of the standard reference and graduate text on laser spectroscopy has been completely revised and expanded. While the general concept is unchanged, the new edition features a broad array of new material, e.g., ultrafast lasers (atto- and femto-second lasers) and parametric oscillators, coherent matter waves, Doppler-free Fourier spectroscopy with optical frequency combs, interference spectroscopy, quantum optics, the interferometric detection of gravitational waves and still more applications in chemical analysis, medical diagnostics, and engineering.

  11. POSIBILIDADES Y LÍMITES DE LA UNIVERSIDAD LATINOAMERICANA DESDE UNA PERSPECTIVA HISTÓRICA POSSIBILITIES AND LIMITS OF THE LATIN AMERICAN UNIVERSITY FROM A HISTORICAL PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    Claudia Milena Jaramillo

    2011-06-01

    Full Text Available La Universidad Latinoamericana se configuró a través de la historia bajo el influjo de diversas fuerzas que le dieron una forma particular dados los contextos específicos donde surgió, en relación con las potencias coloniales, la iglesia, el Estado y el impacto de los diferentes modelos que se establecieron acerca de los propósitos a los que debía atender, definidos por los ingleses, franceses, alemanes y americanos. Pese a los intereses que se ciernen sobre La Universidad Latinoamericana, surgen desde múltiples miradas (las experiencias de México, Perú, Guatemala, Argentina, Chile y Colombia, posibilidades de considerar la idea de estructurar un pensamiento propio, que diera cuenta de una identidad distinta que la separa del discurso eurocentrista y la ubica en una perspectiva de análisis concerniente a las realidades a las que debe hacer frente. En la conformación de la Universidad Latinoamericana se ubican entonces, el pensamiento de Andrés Bello, las ideas de José Vasconcelos y las implicaciones del movimiento de Córdoba, en relación con otros movimientos sociales y estudiantiles con características similares, que convergen en la reflexión acerca de la necesidad de hacer un giro decolonial, no sólo a modo de resistencia, sino de autoconciencia acerca de quiénes somos y cómo cimentar un futuro común, fundamentalmente en esta época cuando la Universidad Latinoamericana enfrenta los embates de la globalización y la aplicación de políticas macroeconómicas que desdibujan su ser social y académico deslegitimándola.Abstract:The Latin American University, throughout history, was shaped under the influence of diverse forces which outlined it in a particular manner, given the specific contexts where it appeared, in relation with colonial powers, the church, the State, and the impact of the different models which were established based on the purposes it had to fulfill, which were defined by the English, the French, the

  12. Reconciliación metodológica e intercultural: posibilidades de la enseñanza comunicativa de lenguas en China

    Directory of Open Access Journals (Sweden)

    Sánchez Griñán, Alberto

    2009-05-01

    Full Text Available Los intentos de implementación, desde los años 80, de una enseñanza comunicativa de lenguas en China no han sido satisfactorios. Con el fin de explorar sus posibilidades, se parte de una problemática similar en la didáctica de lenguas en Occidente, relativa a las dificultades de implementación metodológica y a la dudosa aceptación de la misma por parte de los alumnos occidentales (Lozano y Ruiz, 1996. Se señala la importancia de considerar las posibles soluciones aportadas, teniendo en cuenta los factores contextuales y culturales de la educación en China que influyen en la enseñanza/aprendizaje de lenguas. Se examinan las posibles causas del fracaso de la enseñanza comunicativa en China desde dos perspectivas: la “cultura china de aprendizaje” (Cortazzi y Jin, 1996; Hu, 2002 y las condiciones específicas determinadas por el sistema de evaluación en los centros públicos de enseñanza (Gieve y Clark, 2005. La distinción será relevante a lo largo del artículo, ya que permitirá dilucidar los factores culturales subyacentes y las limitaciones explicables por las condiciones curriculares, aspectos que se han confundido a menudo en la bibliografía. Asimismo, implicará una distinta interpretación de la descripción del “aprendiente chino”. Se describe la situación de la enseñanza / aprendizaje del español en las universidades chinas desde la perspectiva de la continuidad de la tradición educativa, aspecto de especial importancia en la consideración del eclecticismo como vía de reconciliación metodológica entre el modelo de enseñanza más extendido y los enfoques comunicativos. La explotación didáctica de secuencias léxicas no analizadas, o el desarrollo de la competencia formulaica (Celce-Murcia, 2007, puede ser un “puente” hacia la actitud comunicativa en el aprendizaje, dado el potencial de los alumnos chinos en la práctica de la memorización. Asimismo, la enseñanza por tareas revela ser lo

  13. Il laser

    CERN Document Server

    Smith, William V

    1974-01-01

    Verso il 1960, il laser era ancora "una soluzione alla ricerca di un problema", ma fin dagli anni immediatamente successivi si è rivelato uno strumento insostituibile per le applicazioni più svariate.

  14. Laser Refractography

    CERN Document Server

    Rinkevichyus, B.S; Raskovskaya, I.L

    2010-01-01

    This book describes the basic principles of laser refractography, a flexible new diagnostic tool for measuring optically inhomogeneous media and flows. Laser refractography is based on digital imaging and computer processing of structured laser beam refraction (SLR) in inhomogeneous transparent media. Laser refractograms provide both qualitative and quantitative measurements and can be used for the study of fast and transient processes. In this book, the theoretical basis of refractography is explored in some detail, and experimental setups are described for measurement of transparent media using either 2D (passed radiation) or 3D (scattered radiation) refractograms. Specific examples and applications are discussed, including visualization of the boundary layer near a hot or cold metallic ball in water, and observation of edge effects and microlayers in liquids and gases. As the first book to describe this new and exciting technique, this monograph has broad cross-disciplinary appeal and will be of interest t...

  15. Laser fusion

    International Nuclear Information System (INIS)

    Ashby, D.E.T.F.

    1976-01-01

    A short survey is given on laser fusion its basic concepts and problems and the present theoretical and experimental methods. The future research program of the USA in this field is outlined. (WBU) [de

  16. Laser spectroscopy

    International Nuclear Information System (INIS)

    Letokhov, V.S.

    1981-01-01

    This article describes recent progress in the application of laser atomic spectroscopy to study parameters of nuclei available in very small quantities; radioactive nuclei, rare isotopes, nuclear isomers, etc, for which study by conventional spectroscopic methods is difficult. (author)

  17. Laser fusion

    International Nuclear Information System (INIS)

    Key, M.H.; Oxford Univ.

    1990-04-01

    The use of lasers to drive implosions for the purpose of inertially confined fusion is an area of intense activity where progress compares favourably with that made in magnetic fusion and there are significant prospects for future development. In this brief review the basic concept is summarised and the current status is outlined both in the area of laser technology and in the most recent results from implosion experiments. Prospects for the future are also considered. (author)

  18. Laser Resurfacing

    OpenAIRE

    Janik, Joseph P.; Markus, Jodi L.; Al-Dujaili, Zeena; Markus, Ramsey F.

    2007-01-01

    In a society desiring images of beauty and youthfulness, the world of cutaneous surgery offers the gifts of facial rejuvenation for those determined to combat the signs of aging. With the development of novel laser and plasma technology, pigmentary changes, scarring, and wrinkles can be conquered providing smoother, healthier, younger-looking skin. This review highlights five of the most popular resurfacing technologies in practice today including the carbon dioxide (CO2) laser, the erbium:yt...

  19. Green lasers

    DEFF Research Database (Denmark)

    Jensen, Ole Bjarlin

    2010-01-01

    Well over a dozen papers at this year's Photonics West meeting in San Francisco boasted improvements in harmonic generation to produce visible laser beams, most of them in the green spectral range......Well over a dozen papers at this year's Photonics West meeting in San Francisco boasted improvements in harmonic generation to produce visible laser beams, most of them in the green spectral range...

  20. Integración latinoamericana y Educación superior : Reflexión sobre las posibilidades de integración latinoamericana de la educación superior y universitaria

    OpenAIRE

    Brandi, Juan Pedro

    2012-01-01

    Por medio de presente artículo nos planteamos inquirir las posibilidades de integración en América latina para la Educación Superior y Universitaria (ESU). Repasamos las dimensiones que a nuestro entender “asemejan” a una región caracterizada por la heterogeneidad y la fragmentación. Luego consideramos las variables que actúan como limitantes a la consolidación de un espacio de educación integrado. El “modelo” de los sistemas nacionales de la ESU dista de ser único, predominante u homogéneo. ...

  1. POSIBILIDADES DE RE-PENSAR LA ENSEÑANZA DE LO VIVO Y LA VIDA EN LA ESCUELA: UNA LECTURA EN CLAVE DE LA ESTÉTICA Y LA FORMACIÓN DE MAESTROS DE BIOLOGÍA

    Directory of Open Access Journals (Sweden)

    Claudia Jaramillo Sánchez

    2015-12-01

    [1]Las dos investigaciones se constituyen en trabajos de grado desarrollados en el marco de la Licenciatura en Biología y la Especialización en Pedagogía de la Universidad Pedagógica Nacional. La primera lleva como título “FORMAS Y FUERZAS DE LA EXPERIENCIA ESTÉTICA: PINCELADAS, MATICES Y POSIBILIDADES EN LA FORMACIÓN DE MAESTROS DE BIOLOGÍA DE LA UNIVERSIDAD PEDAGÓGICA NACIONAL.” y la segunda se denomina “PRÁCTICAS DISCURSIVAS A PROPÓSITO DE LA BOTÁNICA COMO SABER ESCOLAR ENTRE 1930 Y 1940”

  2. ¿Es posible el matrimonio de las “siete hermanas” del Sur?. Posibilidades de cooperación en petróleo y gas en América Latina (Tema Central)

    OpenAIRE

    Hira, Anil

    2007-01-01

    Este artículo explora las posibilidades de concretar resultados de una de las principales iniciativas del presidente venezolano Hugo Chávez: aumentar la cooperación entre las mayores compañías petroleras de América Latina. Así, se presenta una mirada global de la industria petrolera, un perfil de cada una de estas industrias de América Latina y luego se examinan los obstáculos y los potenciales que presenta esta iniciativa, así como también los pasos necesarios que deben adelantarse para la c...

  3. Laser material processing

    CERN Document Server

    Steen, William

    2010-01-01

    This text moves from the basics of laser physics to detailed treatments of all major materials processing techniques for which lasers are now essential. New chapters cover laser physics, drilling, micro- and nanomanufacturing and biomedical laser processing.

  4. Laser therapy for cancer

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000905.htm Laser therapy for cancer To use the sharing features ... Lasers are also used on the skin. How Laser Therapy is Used Laser therapy can be used ...

  5. Lasers in Cancer Treatment

    Science.gov (United States)

    ... the advantages of laser therapy? What are the disadvantages of laser therapy? What does the future hold ... therapy is appropriate for them. What are the disadvantages of laser therapy? Laser therapy also has several ...

  6. Practical laser safety

    International Nuclear Information System (INIS)

    Winburn, D.C.

    1985-01-01

    This book includes discussions of the following topics: characteristics of lasers; eye components; skin damage thresholds; classification of lasers by ANSI Z136.1; selecting laser-protective eyewear; hazards associated with lasers; and, an index

  7. Laser acceleration

    Science.gov (United States)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-02-01

    The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

  8. Laser acceleration

    International Nuclear Information System (INIS)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-01-01

    The fundamental idea of LaserWakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wake fields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ∼ c and ultra fastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nano materials is also emerging.

  9. Problemáticas socioambientales en la cuenca del río Tunjuelo: una posibilidad en la enseñanza y el aprendizaje de la geografía

    Directory of Open Access Journals (Sweden)

    María Johanna Castaño Pachón

    2015-07-01

    Full Text Available Al analizar los efectos de la intervención antrópica en el espacio geográfico, se evidencia la importancia de la enseñanza geográfica como posibilidad de construir alternativas a la crisis de valores éticos y ambientales que padece la humanidad. “Problemáticas socioambientales en la cuenca del río Tunjuelo: una posibilidad en la enseñanza y el aprendizaje de la geografía” es una experiencia pedagógica originada a partir de la inquietud por acercarse a las dinámicas de la educación geográfica sobre un escenario de la ciudad de Bogotá que refleja una compleja relación entre sociedad y naturaleza como la cuenca del río Tunjuelo, de esta manera, entran en diálogo los argumentos geográficos y pedagógicos convirtiendo el proyecto en una herramienta didáctica para la enseñanza escolar de la ciencia geográfica.

  10. Identidade e profissionalidade docente: sentidos e (impossibilidades Identidad y profesionalidad docente: sentidos, posibilidades e imposibilidades Teaching identity and professional teaching: concepts and (impossibilities

    Directory of Open Access Journals (Sweden)

    José Carlos Morgado

    2011-12-01

    Full Text Available A complexidade do tempo presente e a diversidade de solicitações que hoje se colocam às escolas têm avivado a importância estratégica que a educação continua a ter em termos sociais. Assim se compreende a atenção que a educação tem merecido por parte do poder político e se justificam as reformas desencadeadas com o intuito de adequar os sistemas educativos aos desafios contemporâneos. Nesse processo, tem sido atribuído um papel especial aos professores, já que deles dependem, em grande parte, as transformações a imprimir no ensino e o sucesso educativo dos estudantes. Porém, a possibilidade de os professores perseguirem em melhores condições as finalidades educativas depende, em nosso entender, de três factores: competência profissional, identidade profissional e profissionalidade docente. Partindo dos elementos referidos, reflectimos sobre alguns dos desafios e problemas com que actualmente se confrontam as escolas e os professores e que têm dificultado a mudança e melhoria das suas práticas. Além disso, elencamos vários aspectos fundamentais para revalorizar a profissão e devolver aos professores o protagonismo e o reconhecimento que merecem por parte da sociedade.La complejidad del tiempo presente y la diversidad de solicitaciones que hoy se le plantean a las escuelas han aumentado la importancia estratégica que la educación ha merecido por parte del poder político y también así se justifican las reformas desencadenadas con el objeto de adecuar los sistemas educativos a los desafíos contemporáneos. En ese proceso, se les ha atribuido un rol especial a los profesores, ya que de ellos dependen, en gran parte, las transformaciones que se realizarán en la enseñanza y el éxito educativo de los estudiantes. Pero, la posibilidad de que los profesores persigan en mejores condiciones las finalidades educativas depende, según nuestra opinión, de tres factores: la competencia profesional, la identidad profesional

  11. The neural subject. Contributions to a pedagogy of possibility El sujeto neuronal: Aportaciones para una pedagogía de la posibilidad

    Directory of Open Access Journals (Sweden)

    Teresa N. R. Gonçalves

    2012-07-01

    su plasticidad, multidimensionalidad y capacidad narrativa, entendida como un concepto fundamental relacionado con la construcción de su identidad, y se reflexiona sobre las implicaciones educativas de esta perspectiva en el ámbito de una pedagogía de la posibilidad encuadrada en el marco de la complejidad. 

  12. Laser Heterodyning

    CERN Document Server

    Protopopov, Vladimir V

    2009-01-01

    Laser heterodyning is now a widespread optical technique, based on interference of two waves with slightly different frequencies within the sensitive area of a photo-detector. Its unique feature – preserving phase information about optical wave in the electrical signal of the photo-detector – finds numerous applications in various domains of applied optics and optoelectronics: in spectroscopy, polarimetry, radiometry, laser radars and Lidars, microscopy and other areas. The reader may be surprised by a variety of disciplines that this book covers and satisfied by detailed explanation of the phenomena. Very well illustrated, this book will be helpful for researches, postgraduates and students, working in applied optics.

  13. Laser polarimetry

    International Nuclear Information System (INIS)

    Goldstein, D.H.

    1989-01-01

    Polarimetry, or transmission ellipsometry, is an important experimental technique for the determination of polarization properties of bulk materials. In this technique, source radiation of known polarization is passed through bulk samples to determine, for example, natural or induced birefringence and dichroism. The laser is a particularly appropriate source for this technique because of its monochromaticity, collimation, and radiant intensity. Lasers of many different wavelengths in different spectral regions are now available. Laser polarimetry can be done in any of these wavelength regions where polarizing elements are available. In this paper, polarimetry is reviewed with respect to applications, sources used, and polarization state generator and analyzer configurations. Scattering ellipsometry is also discussed insofar as the forward scattering measurement is related to polarimetry. The authors then describe an infrared laser polarimeter which we have designed and constructed. This instrument can operate over large wavelength regions with only a change in source. Polarization elements of the polarimeter are in a dual rotating retarder configuration. Computer controlled rotary stages and computer monitored detectors automate the data collection. The Mueller formulation is used to process the polarization information. Issues and recent progress with this instrument are discussed

  14. excimer laser

    Indian Academy of Sciences (India)

    2014-01-07

    Jan 7, 2014 ... is necessary to deposit one order higher input electric power into gas medium than ... cross-sectional view of the laser system is shown in figure 2A. The system mainly consists ... Considering the simplicity and reliability of the.

  15. Laser device

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention provides a light source for light circuits on a silicon platform. A vertical laser cavity is formed by a gain region arranged between a first mirror structure and a second mirror structure, both acting as mirrors, by forming a grating region including an active material...

  16. Nanowire Lasers

    Directory of Open Access Journals (Sweden)

    Couteau C.

    2015-05-01

    Full Text Available We review principles and trends in the use of semiconductor nanowires as gain media for stimulated emission and lasing. Semiconductor nanowires have recently been widely studied for use in integrated optoelectronic devices, such as light-emitting diodes (LEDs, solar cells, and transistors. Intensive research has also been conducted in the use of nanowires for subwavelength laser systems that take advantage of their quasione- dimensional (1D nature, flexibility in material choice and combination, and intrinsic optoelectronic properties. First, we provide an overview on using quasi-1D nanowire systems to realize subwavelength lasers with efficient, directional, and low-threshold emission. We then describe the state of the art for nanowire lasers in terms of materials, geometry, andwavelength tunability.Next,we present the basics of lasing in semiconductor nanowires, define the key parameters for stimulated emission, and introduce the properties of nanowires. We then review advanced nanowire laser designs from the literature. Finally, we present interesting perspectives for low-threshold nanoscale light sources and optical interconnects. We intend to illustrate the potential of nanolasers inmany applications, such as nanophotonic devices that integrate electronics and photonics for next-generation optoelectronic devices. For instance, these building blocks for nanoscale photonics can be used for data storage and biomedical applications when coupled to on-chip characterization tools. These nanoscale monochromatic laser light sources promise breakthroughs in nanophotonics, as they can operate at room temperature, can potentially be electrically driven, and can yield a better understanding of intrinsic nanomaterial properties and surface-state effects in lowdimensional semiconductor systems.

  17. Excimer Laser Technology

    CERN Document Server

    Basting, Dirk

    2005-01-01

    This comprehensive survey on Excimer Lasers investigates the current range of the technology, applications and devices of this commonly used laser source, as well as the future of new technologies, such as F2 laser technology. Additional chapters on optics, devices and laser systems complete this compact handbook. A must read for laser technology students, process application researchers, engineers or anyone interested in excimer laser technology. An effective and understandable introduction to the current and future status of excimer laser technology.

  18. Laser ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Bykovskij, Yu

    1979-02-01

    The characteristics a laser source of multiply-ionized ions are described with regard to the interaction of laser radiation and matter, ion energy spectrum, angular ion distribution. The amount of multiple-ionization ions is evaluated. Out of laser source applications a laser injector of multiple-ionization ions and nuclei, laser mass spectrometry, laser X-ray microradiography, and a laser neutron generators are described.

  19. La investigación y la política: ensayo sobre las posibilidades de construcción y reconstrucción de un objeto de estudio

    Directory of Open Access Journals (Sweden)

    Moreles Vázquez, Jaime

    2007-08-01

    Full Text Available Resumen: Este ensayo analiza las posibilidades de la construcción del objeto en un ejercicio de investigación. Se asume que en un proceso de investigación lo propio del investigador es el manejo de la información obtenida de las fuentes relacionadas con su objeto de estudio, sean éstas teóricas o empíricas; es esta reconstrucción lo que pertenece verdaderamente al investigador. A partir de estos supuestos se argumenta sobre las posibilidades que brinda la teoría social y la epistemología a un objeto de estudio específico.La estructura del documento es la siguiente: primero se realiza una breve reseña de la investigación que el autor está desarrollando como tesis doctoral, con el objeto de contextualizar al lector en la dirección que seguirán los ejemplos derivados de los argumentos por discernir. En segundo término se plantea la sustancia de este ejercicio ensayístico, a partir de la manera en que se encuentra un objeto en un campo de estudio determinado y las posibilidades del investigador para reconstruirlo en un ejercicio con proyección empírica o teórica. Finalmente, se plantea una agenda de discusión.Abstract: In this paper we present an analysis of the construction of the object, within the practice of educational research. It is assumed that the role of the researcher deals with handling the data obtained from sources related to the object of study, whether theoretical or empirical. This reconstruction of the constructed object is what truly belongs to the researcher. From these assumptions, it is discussed about the potential contributions of social theory and epistemology in a particular object of study.The manuscript is structured as follows. First, it presents a brief review of author’s research under development for his doctoral thesis. The purpose is to put in to perspective the examples that come from the arguments to be discerned. Next, it is described the main point of the exposition. Author’s reasoning

  20. Dermatological laser treatment

    International Nuclear Information System (INIS)

    Moerk, N.J.; Austad, J.; Helland, S.; Thune, P.; Volden, G.; Falk, E.

    1991-01-01

    The article reviews the different lasers used in dermatology. Special emphasis is placed on the treatment of naevus flammeus (''portwine stain'') where lasers are the treatment of choice. Argon laser and pulsed dye laser are the main lasers used in vascular skin diseases, and the article focuses on these two types. Copper-vapour laser, neodymium-YAG laser and CO 2 laser are also presented. Information is provided about the availability of laser technology in the different health regions in Norway. 5 refs., 2 figs

  1. La reforma realizada en el año 2002 al artículo 195 de la constitución política: La posibilidad de someter a referéndum una reforma constitucional

    Directory of Open Access Journals (Sweden)

    Esteban Alfaro Calderón

    2008-01-01

    Full Text Available Análisis de la reforma realizada al inciso 8 del artículo 195 de la Constitución Política en el año 2002; sobre la posibilidad de someter a referéndum las reformas constitucionales después de ser aprobadas en una legislatura y antes de la siguiente, esto si dos terceras partes de los miembros de la Asamblea así lo acuerdan. Hace un estudio desde la perspectiva de quienes la apoyan, así como de sus detractores. Adicionalmente realiza una investigación de doctrina y jurisprudencia de la Sala Constitucional y del Tribunal Supremo de Elecciones, en lo que al referéndum y al principio de participación se refiere.

  2. Posibilidades del escalamiento subjetivo como técnica de análisis del pensamiento espontáneo del profesorado de ciencias en formación

    Directory of Open Access Journals (Sweden)

    Pedro Álvarez-Suárez

    2013-01-01

    Full Text Available El método de las comparaciones binarias es una técnica multivariante de Escalamiento Multidimensional basado en la comparación de objetos o estímulos, aunque se encuentra escasamente utilizado. El objetivo de este estudio es mostrar la utilidad de dicho método para analizar la valoración que realiza el profesorado de Ciencias en formación, en el contexto del nuevo Master de Educación Secundaria, sobre algunos de los problemas que presentan la enseñanza y el aprendizaje de las Ciencias Experimentales. Los resultados muestran las posibilidades del método empleado como punto de partida en la planificación de proyectos de formación para este profesorado.

  3. La Recuperación del Patrimonio Histórico-Educativo. Museos de Pedagogía, Enseñanza y Educación y Posibilidades Didácticas

    Directory of Open Access Journals (Sweden)

    Pablo Álvarez Domínguez

    2011-06-01

    Full Text Available (ES Recoge este trabajo el resultado de una experiencia formativa organizada por el Museo Pedagógico Andaluz y desarrollada el pasado mes de Octubre de 2010 en la Facultad de Ciencias de la Educación de la Universidad de Sevilla. Todo ello, con la finalidad de propiciar una reflexión teórico-práctica ligada a poner de manifiesto las nuevas posibilidades didácticas del patrimonio histórico-educativo que se pueden desplegar en el ámbito museístico-pedagógico, con el fin de facilitar su estudio, comprensión y valoración.

  4. CO2-laser fusion

    International Nuclear Information System (INIS)

    Stark, E.E. Jr.

    1978-01-01

    The basic concept of laser fusion is described, with a set of requirements on the laser system. Systems and applications concepts are presented and discussed. The CO 2 laser's characteristics and advantages for laser fusion are described. Finally, technological issues in the development of CO 2 laser systems for fusion applications are discussed

  5. Project LASER

    Science.gov (United States)

    1990-01-01

    NASA formally launched Project LASER (Learning About Science, Engineering and Research) in March 1990, a program designed to help teachers improve science and mathematics education and to provide 'hands on' experiences. It featured the first LASER Mobile Teacher Resource Center (MTRC), is designed to reach educators all over the nation. NASA hopes to operate several MTRCs with funds provided by private industry. The mobile unit is a 22-ton tractor-trailer stocked with NASA educational publications and outfitted with six work stations. Each work station, which can accommodate two teachers at a time, has a computer providing access to NASA Spacelink. Each also has video recorders and photocopy/photographic equipment for the teacher's use. MTRC is only one of the five major elements within LASER. The others are: a Space Technology Course, to promote integration of space science studies with traditional courses; the Volunteer Databank, in which NASA employees are encouraged to volunteer as tutors, instructors, etc; Mobile Discovery Laboratories that will carry simple laboratory equipment and computers to provide hands-on activities for students and demonstrations of classroom activities for teachers; and the Public Library Science Program which will present library based science and math programs.

  6. Laser Research Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The Laser Research lab is thecenter for the development of new laser sources, nonlinear optical materials, frequency conversion processes and laser-based sensors for...

  7. Laser therapy (image)

    Science.gov (United States)

    A laser is used for many medical purposes. Because the laser beam is so small and precise, it enables ... without injuring surrounding tissue. Some uses of the laser are retinal surgery, excision of lesions, and cauterization ...

  8. Laser fusion: an overview

    International Nuclear Information System (INIS)

    Boyer, K.

    1975-01-01

    The laser fusion concept is described along with developments in neodymium and carbon dioxide lasers. Fuel design and fabrication are reviewed. Some spin-offs of the laser fusion program are discussed. (U.S.)

  9. Laser power supply

    International Nuclear Information System (INIS)

    Bernstein, D.

    1975-01-01

    The laser power supply includes a regulator which has a high voltage control loop based on a linear approximation of a laser tube negative resistance characteristic. The regulator has independent control loops for laser current and power supply high voltage

  10. Bleaching Dengan Teknologi Laser

    OpenAIRE

    Eliwaty

    2008-01-01

    Penulisan tentang bleaching dengan laser dimaksudkan untuk menambah wawasan serta pengetahuan dari pembaca di bidang kedokteran gigi. Macam-macam laser yang dipergunakan dalam bleaching yaitu argon, CO2 serta dioda laser. Contoh merek produk laser yaitu Blulaze, Dentcure untuk argonlaser, Novapulse untuk C02 serta Opus 5 untuk dioda laser. Laser bleaching hasilnya dapat dicapai dalam satu kunjungan saja, cepat, efisien namun biayanya relatif mahal, dapat menimbulkan burn, sensitivitas se...

  11. Laser safety at high profile laser facilities

    International Nuclear Information System (INIS)

    Barat, K.

    2010-01-01

    Complete text of publication follows. Laser safety has been an active concern of laser users since the invention of the laser. Formal standards were developed in the early 1970's and still continue to be developed and refined. The goal of these standards is to give users guidance on the use of laser and consistent safety guidance and requirements for laser manufacturers. Laser safety in the typical research setting (government laboratory or university) is the greatest challenge to the laser user and laser safety officer. This is due to two factors. First, the very nature of research can put the user at risk; consider active manipulation of laser optics and beam paths, and user work with energized systems. Second, a laser safety culture that seems to accept laser injuries as part of the graduate student educational process. The fact is, laser safety at research settings, laboratories and universities still has long way to go. Major laser facilities have taken a more rigid and serious view of laser safety, its controls and procedures. Part of the rationale for this is that these facilities draw users from all around the world presenting the facility with a work force of users coming from a wide mix of laser safety cultures. Another factor is funding sources do not like bad publicity which can come from laser accidents and a poor safety record. The fact is that injuries, equipment damage and lost staff time slow down progress. Hence high profile/large laser projects need to adapt a higher safety regimen both from an engineering and administrative point of view. This presentation will discuss all these points and present examples. Acknowledgement. This work has been supported by the University of California, Director, Office of Science.

  12. Semiconductor Laser Measurements Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Semiconductor Laser Measurements Laboratory is equipped to investigate and characterize the lasing properties of semiconductor diode lasers. Lasing features such...

  13. Laser Protection TIL

    Data.gov (United States)

    Federal Laboratory Consortium — The Laser Protection TIL conducts research and analysis of laser protection materials along with integration schemes. The lab's objectives are to limit energy coming...

  14. Laser Photochemistry.

    Science.gov (United States)

    1981-07-01

    inverted by the first, i.e., at the moment of time t = T, such that i = (2n+)lT, where 0 is the Rabi frequency (Oraevski et al., 1976). . classical... anisotropic molecule present. CW HeNe, Ar+ and Kr+ lasers are used, and the filter method is necessary because of time-scales lo8 - 10ll Hz. Some general...e.g., truncated harmonic oscillator, square well, spherically symmetric Morse or Lennard-Jones, anisotropic (angle-dependent) Morse or Lennard-Jones

  15. Posibilidades del mecanizado por ultrasonidos rotatorio para fomentar el uso de las cerámicas técnicas en el mercado Español actual

    Directory of Open Access Journals (Sweden)

    Arriola, I.

    2012-08-01

    Full Text Available The advanced properties of engineering ceramics are suitable to meet the requirements of several engineering applications such as medical (prosthesis…, automotive (bearing..., aerospace (tiles,..., optics (lasers,… and so on, where high hardness, high wear resistance and thermo chemical stability are needed. However, the processing of these materials is difficult and costly, in some cases up to 90% of the price, which leads ceramics to limited applications. Rotary Ultrasonic Machining (RUM is presented as a non conventional environmental-friendly and cost effective process that enables to obtain complex 3D shape ceramic products. A rotating tool with metal-bonded diamond abrasives is ultrasonically vibrated (typically 20KHz and fed toward to the fixed workpiece at a constant pressure or a constant feed rate This process combines conventional grinding and ultrasonic machining, offering the possibility of increased material removal rates while keeping the machining forces low. Thus, the limitations of actually used conventional processes are overcome introducing more accurate, flexible and cost effective process capabilities. On balance, RUM is a promising process for primary machining operations on structural ceramic components. Its features will lead to enhance the use of ceramics in more industrial applications by increasing product development/design capabilities, high added value products and sustainable process.

    Las propiedades mecánicas de las cerámicas técnicas son adecuadas para aplicaciones en diferentes sectores como la medicina (prótesis,..., automóvil (rodamientos,…., aeroespacial (loseta,…, óptica (láser,…, etc. donde se requieren características como la gran resistencia al desgaste, alta dureza y estabilidad termoquímica. Sin embargo, la fabricación de estos materiales es difícil y costosa, en algunos casos alcanzando el 90% del coste final, por lo que su aplicación está limitada. Este trabajo

  16. Laser Propulsion - Quo Vadis

    International Nuclear Information System (INIS)

    Bohn, Willy L.

    2008-01-01

    First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient and specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community

  17. Laser safety and practice

    International Nuclear Information System (INIS)

    Low, K.S.

    1995-01-01

    Lasers are finding increasing routine applications in many areas of science, medicine and industry. Though laser radiation is non-ionizing in nature, the usage of high power lasers requires specific safety procedures. This paper briefly outlines the properties of laser beams and various safety procedures necessary in their handling and usage. (author)

  18. Diode lasers and arrays

    International Nuclear Information System (INIS)

    Streifer, W.

    1988-01-01

    This paper discusses the principles of operation of III-V semiconductor diode lasers, the use of distributed feedback, and high power laser arrays. The semiconductor laser is a robust, miniature, versatile device, which directly converts electricity to light with very high efficiency. Applications to pumping solid-state lasers and to fiber optic and point-to-point communications are reviewed

  19. Laser cladding with powder

    NARCIS (Netherlands)

    Schneider, M.F.; Schneider, Marcel Fredrik

    1998-01-01

    This thesis is directed to laser cladding with powder and a CO2 laser as heat source. The laser beam intensity profile turned out to be an important pa6 Summary rameter in laser cladding. A numerical model was developed that allows the prediction of the surface temperature distribution that is

  20. Semiconductor laser shearing interferometer

    International Nuclear Information System (INIS)

    Ming Hai; Li Ming; Chen Nong; Xie Jiaping

    1988-03-01

    The application of semiconductor laser on grating shearing interferometry is studied experimentally in the present paper. The method measuring the coherence of semiconductor laser beam by ion etching double frequency grating is proposed. The experimental result of lens aberration with semiconductor laser shearing interferometer is given. Talbot shearing interferometry of semiconductor laser is also described. (author). 2 refs, 9 figs

  1. Visible Solid State Lasers

    NARCIS (Netherlands)

    Hikmet, R.A.M.

    2007-01-01

    Diode lasers can be found in various applications most notably in optical communication and optical storage. Visible lasers were until recently were all based on IR diode lasers. Using GaN, directly blue and violet emitting lasers have also been introduced to the market mainly in the area of optical

  2. Laser Microdissection.

    Science.gov (United States)

    Frost, Andra R; Eltoum, Isam-Eldin; Siegal, Gene P; Emmert-Buck, Michael R; Tangrea, Michael A

    2015-10-01

    Laser microdissection (LM) offers a relatively rapid and precise method of isolating and removing specified cells from complex tissues for subsequent analysis of their RNA, DNA, protein or metabolite content, thereby allowing assessment of the role of different cell types in the normal physiological or disease processes being studied. In this unit, protocols for the preparation of mammalian frozen tissues, fixed tissues, and cytologic specimens for LM, including tissue freezing, tissue processing and paraffin embedding, histologic sectioning, cell processing, hematoxylin and eosin staining, immunohistochemistry, and image-guided cell targeting are presented. Also provided are recipes for generating lysis buffers for the recovery of nucleic acids and proteins. The Commentary section addresses the types of specimens that can be utilized for LM and approaches to staining of specimens for cell visualization. Emphasis is placed on the preparation of tissue or cytologic specimens as this is critical to effective LM. Copyright © 2015 John Wiley & Sons, Inc.

  3. Laser EXAFS

    International Nuclear Information System (INIS)

    Mallozzi, P.J.; Epstein, H.M.; Schwenzel, R.E.; Campbell, B.E.

    1983-01-01

    Apparatus for obtaining EXAFS data of a material, comprising means for directing radiant energy from a laser onto a target in such manner as to produce X-rays at the target of a selected spectrum and intensity, suitable for obtaining the EXAFS spectrum of the material, means for directing X-rays from the target onto spectral dispersive means so located as to direct the spectrally resolved X-rays therefrom onto recording means, and means for positioning a sample of material in the optical path of the X-rays, the recording means providing a reference spectrum of X-rays not affected by the sample and absorption spectrum of X-rays modified by transmission through the sample

  4. Multibeam Fibre Laser Cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    The appearance of the high power high brilliance fibre laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating cutting laser, the CO2-laser. However, quality problems in fibre......-laser cutting have until now limited its application in metal cutting. In this paper the first results of proof-of-principle studies applying a new approach (patent pending) for laser cutting with high brightness short wavelength lasers will be presented. In the approach, multi beam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from 2 single mode fibre lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W of single...

  5. Multibeam fiber laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Hansen, Klaus Schütt; Nielsen, Jakob Skov

    2009-01-01

    The appearance of the high power high brilliance fiber laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating Cutting laser, the CO2 laser. However, quality problems in fiber......-laser cutting have until now limited its application to metal cutting. In this paper the first results of proof-of-principle Studies applying a new approach (patent pending) for laser cutting with high brightness and short wavelength lasers will be presented. In the approach, multibeam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from two single mode fiber lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W...

  6. History and principle of lasers

    International Nuclear Information System (INIS)

    Townes, Ch.H.; Schwob, C.; Julien, J.; Forget, S.; Robert-Philip, I.; Balcou, Ph.

    2010-01-01

    In the first article C.H. Townes, the inventor of the maser, describes the work and ideas that led to the invention of the laser. The second article explains how a laser operate and the third article reviews the main different types of laser: solid lasers, gas lasers, diode lasers and dye lasers

  7. Technological laser application

    International Nuclear Information System (INIS)

    Shia, D.O.; Kollen, R.; Rods, U.

    1980-01-01

    Problems of the technological applications of lasers are stated in the popular form. Main requirements to a technological laser as well as problems arising in designing any system using lasers have been considered. Areas of the laser applications are described generally: laser treatment of materials, thermal treatment, welding, broach and drilling of holes, scribing, microtreatment and adjustment of resistors, material cutting, investigations into controlled thermonuclear fussion

  8. Laser ablation principles and applications

    CERN Document Server

    1994-01-01

    Laser Ablation provides a broad picture of the current understanding of laser ablation and its many applications, from the views of key contributors to the field. Discussed are in detail the electronic processes in laser ablation of semiconductors and insulators, the post-ionization of laser-desorbed biomolecules, Fourier-transform mass spectroscopy, the interaction of laser radiation with organic polymers, laser ablation and optical surface damage, laser desorption/ablation with laser detection, and laser ablation of superconducting thin films.

  9. New power lasers

    International Nuclear Information System (INIS)

    Yamanaka, Masanobu; Daido, Hiroyuki; Imasaki, Kazuo.

    1989-01-01

    As the new power lasers which are expected to exert large extending effect to the fields of advanced science and technology including precision engineering as well as laser nuclear fusion, LD-excited solid laser, X-ray laser and free electron laser are taken up and outlined. Recently, the solid laser using high power output, high efficiency semiconductor laser as the exciting beam source has been developed. This is called laser diode (LD)-excited solid laser, and the heightening of power output and efficiency and the extension of life are planned. Its present status and application to medical use, laser machining, laser soldering and so on are described. In 1960, the laser in visible region appeared, however in 1985, the result of observing induced emission beam by electron collision exciting method was reported in USA. In the wavelength range of 200 A, holography and contact X-ray microscope applications were verified. The various types of soft X-ray laser and the perspective hereafter are shown. The principle of free electron laser is explained. In the free electron laser, wavelength can be changed by varying electron beam energy, the period of wiggler magnetic field and the intensity of magnetic field. Further, high efficiency and large power output are possible. Its present status, application and the perspective hereafter are reported. (K.I.)

  10. Laser applications in materials processing

    International Nuclear Information System (INIS)

    Ready, J.F.

    1980-01-01

    The seminar focused on laser annealing of semiconductors, laser processing of semiconductor devices and formation of coatings and powders, surface modification with lasers, and specialized laser processing methods. Papers were presented on the theoretical analysis of thermal and mass transport during laser annealing, applications of scanning continuous-wave and pulsed lasers in silicon technology, laser techniques in photovoltaic applications, and the synthesis of ceramic powders from laser-heated gas-phase reactants. Other papers included: reflectance changes of metals during laser irradiation, surface-alloying using high-power continuous lasers, laser growth of silicon ribbon, and commercial laser-shock processes

  11. La apropiación del dominio público y las posibilidades de acceso a los bienes culturales | The appropriation of the public domain and the possibilities of access to cultural goods

    Directory of Open Access Journals (Sweden)

    Joan Ramos Toledano

    2017-06-01

    Full Text Available Resumen: Las normas de propiedad intelectual y copyright prevén un periodo de protección otorgando unos derechos económicos exclusivos y temporales. Pasado un plazo determinado, las obras protegidas entran en lo que se denomina dominio público. Éste suele ser considerado como el momento en el que los bienes culturales pasan a estar bajo el dominio y control de la sociedad en conjunto. El presente trabajo pretende argumentar que, dado nuestro actual sistema económico, en realidad el dominio público funciona más como una posibilidad de negocio para determinadas empresas que como una verdadera opción para que el público pueda acceder a las obras.   Abstract: The legislation of continental intellectual property and copyright provide for a period of protection granting exclusive and temporary economic rights. After a certain period, protected works enter into what is called the public domain. This is often considered as the moment in which the cultural goods come under the control and domain of society as a whole. The present paper pretends to argue that, given our current economic system, the public domain actually functions more as a business opportunity for certain companies than as a real option for the public to access artistic and intellectual works.

  12. Las relaciones entre teóricos/investigadores y decisores/profesionales: repensando la tesis de las dos culturas y la posibilidad de diálogo en el sector educativo

    Directory of Open Access Journals (Sweden)

    Mark B. Ginsburg

    2005-01-01

    Full Text Available Este artículo examina el tema de las relaciones entre teóricos, investigadores, decisores políticos y profesionales en el campo de la educación internacional. Se muestran las limitaciones de la tesis de "las dos culturas" como explicación de los problemas de comunicación entre los diversos actores, y se señala la necesidad de considerar a otros miembros de las comunidades locales, nacionales e internacionales (alumnos, padres, etc. en las cuales se desarrolla la praxis educativa. A continuación, se discuten seis enfoques para mejorar la comunicación y las posibilidades de establecer un diálogo como reflexión y acción conjunta: (1 traducción/mediación, (2 educación, (3 expansión de roles, (4 investigación orientada a la decisión, (5 investigación-acción colaborativa, e (6 investigación y praxis colectiva. 

  13. Las tecnologías de la información y la comunicación en la Educación Física de Primaria: estudio sobre sus posibilidades educativas

    Directory of Open Access Journals (Sweden)

    Marta Capllonch Bujosa

    2006-06-01

    Full Text Available En un momento de revolución tecnológica, completamente inmersos en la sociedad de la información como herencia del siglo xx, y dado que ya no es posible desatar educación de tecnología, se plantea esta tesis doctoral desde la perspectiva de la Educación Física escolar, con el objeto de orientar unos criterios que tarde o temprano se habían de abordar. Entre los elementos que justifican la necesidad de la búsqueda se podría destacar un nuevo marco legislativo en Educación, que debe procurar la integración de conocimientos más acuerdos con las necesidades del momento; proporcionar el uso de las TIC en el espacio escolar desde diferentes perspectivas, o bien contribuir a garantizar el acceso a las TIC de todas las personas. Desde otra perspectiva, la Educación Física no se puede quedar indiferente con las posibilidades que ofrecen las TIC: “motivación”, “flexibilidad”, “personalización”, “interactividad”, “aprendizaje autónomo y colaborativo”... El objetivo principal de la tesis, centrada en determinar el tratamiento que deben tener las TIC en la Educación Física escolar, tanto desde la perspectiva del profesorado como del alumnado, se aborda desde diferentes perspectivas. Por un lado las circunstancias que rodean el uso de las TIC en la Educación Primaria. Por otro lado, se orienta a conocer el uso real que hace el profesorado de Educación Física de la tecnología, y recoger las experiencias existentes en este ámbito. Finalmente, se busca profundizar en aquellos aspectos de las TIC que pueden aportar mayor beneficios a la Educación Física escolar. Se utiliza un diseño de búsqueda cualitativo que, no obstante, combina o integra el uso de técnicas de recogida de información cuantitativas y cualitativas. En concreto se utilizan como instrumentos un cuestionario autoadministrado con presencia de encuestador, y como estrategias entrevistas exploratorias a personas expertas, grupos de discusión de

  14. Límites y posibilidades de la práctica del cine etnográfico desde la antropología visual (Limits and possibilities of the practice of ethnographic film from Visual Anthropology

    Directory of Open Access Journals (Sweden)

    Sergio Úbeda Álvarez

    2016-05-01

    Full Text Available Resumen: El siguiente artículo repasa la historia de la antropología visual desde la práctica de su herramienta más reclamada: el cine. Cine y antropología son proyectos que se desarrollan durante el siglo XX, del modernismo al postmodernismo, confluyendo en algunas ocasiones y distanciándose en muchas otras. Este artículo revisa las posibilidades epistemológicas que ha permitido el medio visual, en concreto el cine, y el tipo de utilidad que pueden aportar en el futuro las técnicas audiovisuales para la antropología.Abstract: The following article is a review of the history of visual anthropology from the practice of their most demanded tool: the cinema. Cinema and anthropology are projects being developed in the twentieth century, from modernism to postmodernism, some times converging and distancing in many others. The epistemological possibilities that visual media and films has allowed in the past and may have in the future for anthropology are rewiewed in this article.

  15. Raman fiber lasers

    CERN Document Server

    2017-01-01

    This book serves as a comprehensive, up-to-date reference about this cutting-edge laser technology and its many new and interesting developments. Various aspects and trends of Raman fiber lasers are described in detail by experts in their fields. Raman fiber lasers have progressed quickly in the past decade, and have emerged as a versatile laser technology for generating high power light sources covering a spectral range from visible to mid-infrared. The technology is already being applied in the fields of telecommunication, astronomy, cold atom physics, laser spectroscopy, environmental sensing, and laser medicine. This book covers various topics relating to Raman fiber laser research, including power scaling, cladding and diode pumping, cascade Raman shifting, single frequency operation and power amplification, mid-infrared laser generation, specialty optical fibers, and random distributed feedback Raman fiber lasers. The book will appeal to scientists, students, and technicians seeking to understand the re...

  16. Ceramic Laser Materials

    Directory of Open Access Journals (Sweden)

    Guillermo Villalobos

    2012-02-01

    Full Text Available Ceramic laser materials have come a long way since the first demonstration of lasing in 1964. Improvements in powder synthesis and ceramic sintering as well as novel ideas have led to notable achievements. These include the first Nd:yttrium aluminum garnet (YAG ceramic laser in 1995, breaking the 1 KW mark in 2002 and then the remarkable demonstration of more than 100 KW output power from a YAG ceramic laser system in 2009. Additional developments have included highly doped microchip lasers, ultrashort pulse lasers, novel materials such as sesquioxides, fluoride ceramic lasers, selenide ceramic lasers in the 2 to 3 μm region, composite ceramic lasers for better thermal management, and single crystal lasers derived from polycrystalline ceramics. This paper highlights some of these notable achievements.

  17. Infrared laser system

    International Nuclear Information System (INIS)

    Cantrell, C.D.; Carbone, R.J.

    1977-01-01

    An infrared laser system and method for isotope separation may comprise a molecular gas laser oscillator to produce a laser beam at a first wavelength, Raman spin flip means for shifting the laser to a second wavelength, a molecular gas laser amplifier to amplify said second wavelength laser beam to high power, and optical means for directing the second wavelength, high power laser beam against a desired isotope for selective excitation thereof in a mixture with other isotopes. The optical means may include a medium which shifts the second wavelength high power laser beam to a third wavelength, high power laser beam at a wavelength coincidental with a corresponding vibrational state of said isotope and which is different from vibrational states of other isotopes in the gas mixture

  18. Ceramic Laser Materials

    Science.gov (United States)

    Sanghera, Jasbinder; Kim, Woohong; Villalobos, Guillermo; Shaw, Brandon; Baker, Colin; Frantz, Jesse; Sadowski, Bryan; Aggarwal, Ishwar

    2012-01-01

    Ceramic laser materials have come a long way since the first demonstration of lasing in 1964. Improvements in powder synthesis and ceramic sintering as well as novel ideas have led to notable achievements. These include the first Nd:yttrium aluminum garnet (YAG) ceramic laser in 1995, breaking the 1 KW mark in 2002 and then the remarkable demonstration of more than 100 KW output power from a YAG ceramic laser system in 2009. Additional developments have included highly doped microchip lasers, ultrashort pulse lasers, novel materials such as sesquioxides, fluoride ceramic lasers, selenide ceramic lasers in the 2 to 3 μm region, composite ceramic lasers for better thermal management, and single crystal lasers derived from polycrystalline ceramics. This paper highlights some of these notable achievements. PMID:28817044

  19. Spectroscopic and imaging diagnostics of pulsed laser deposition laser plasmas

    International Nuclear Information System (INIS)

    Thareja, Raj K.

    2002-01-01

    An overview of laser spectroscopic techniques used in the diagnostics of laser ablated plumes used for thin film deposition is given. An emerging laser spectroscopic imaging technique for the laser ablation material processing is discussed. (author)

  20. Lasers in periodontics.

    Science.gov (United States)

    Elavarasu, Sugumari; Naveen, Devisree; Thangavelu, Arthiie

    2012-08-01

    Laser is one of the most captivating technologies in dental practice since Theodore Maiman in 1960 invented the ruby laser. Lasers in dentistry have revolutionized several areas of treatment in the last three and a half decades of the 20(th) century. Introduced as an alternative to mechanical cutting device, laser has now become an instrument of choice in many dental applications. Evidence suggests its use in initial periodontal therapy, surgery, and more recently, its utility in salvaging implant opens up a wide range of applications. More research with better designs are a necessity before lasers can become a part of dental armamentarium. This paper gives an insight to laser in periodontics.

  1. Excimer laser applications

    International Nuclear Information System (INIS)

    Fantoni, R.

    1988-01-01

    This lecture deals with laser induced material photoprocessing, especially concerning those processes which are initiated by u.v. lasers (mostly excimer laser). Advantages of using the u.v. radiation emitted by excimer lasers, both in photophysical and photochemical processes of different materials, are discussed in detail. Applications concerning microelectronics are stressed with respect to other applications in different fields (organic chemistry, medicine). As further applications of excimer lasers, main spectroscopic techniques for ''on line'' diagnostics which employ excimer pumped dye lasers, emitting tunable radiation in the visible and near u.v. are reviewed

  2. Lasers in chemical processing

    International Nuclear Information System (INIS)

    Davis, J.I.

    1982-01-01

    The high cost of laser energy is the crucial issue in any potential laser-processing application. It is expensive relative to other forms of energy and to most bulk chemicals. We show those factors that have previously frustrated attempts to find commercially viable laser-induced processes for the production of materials. Having identified the general criteria to be satisfied by an economically successful laser process and shown how these imply the laser-system requirements, we present a status report on the uranium laser isotope separation (LIS) program at the Lawrence Livermore National Laboratory

  3. Laser in urology. Laser i urologien

    Energy Technology Data Exchange (ETDEWEB)

    Breisland, H.O. (Aker Sykehus, Oslo (Norway))

    1991-09-01

    The neodymium YAG laser is particularly suited for endoscopic urologic surgery because the YAG laser light can be conducted in flexible fibers. Superficial bladder tumours can be treated under local anaesthesia in the outpatient department. The frequency of local recurrences is low, significantly lower than after electrosection or electrocoagulation. Selected cases of T2-muscle invasive bladder tumours can be cured with laser coagulation applied subsequently to transurethral resection. Combined treatment with electrosection and laser coagulation of localized prostatic cancer is a promising method which compares favourably with results obtained by other treatment modalities. Tumours in the upper urinary tract can be laser-treated through ureteroscopes or nephroscopes, but the treatment should be limited to low stage, low grade tumours. Laser is the treatment of choice for intraurethral condylomatas. Laser treatment of penil carcinoma gives excellent cosmetic and functional results and few local recurrences. Laser lithotripsy is a new technique for treatment of ureteric stones and photodynamic laser therapy is a promising tecnique for treatment of carcinoma in situ in the bladder empithelium. However, neither of these techniques are available for clinical use in Norway as yet. 17 refs., 3 figs., 1 tabs.

  4. Laser materials processing with diode lasers

    OpenAIRE

    Li, Lin; Lawrence, Jonathan; Spencer, Julian T.

    1996-01-01

    Laser materials processing is currently dominated by CO2, Nd-YAG and Excimer lasers. Continuous advances in semiconductor laser technology over the last decade have increased the average power output of the devices annualy by two fold, resulting in the commercial availability of the diode lasers today with delivery output powers in excess of 60W in CW mode and 5kW in qasi-CW mode. The advantages of compactness, high reliability, high efficiency and potential low cost, due to the mass producti...

  5. 1982 laser program annual report

    International Nuclear Information System (INIS)

    Hendricks, C.D.; Grow, G.R.

    1983-08-01

    This annual report covers the following eight sections: (1) laser program review, (2) laser systems and operation, (3) target design, (4) target fabrication, (5) fusion experiments program, (6) Zeus laser project, (7) laser research and development, and (8) energy applications

  6. Condiciones de posibilidad para una justicia global

    Directory of Open Access Journals (Sweden)

    Pereira, Gustavo

    2004-06-01

    Full Text Available Recognition, as a constitutive part of subjectivity, is a basic need for people as well as for States. The terms of international relationships imposed by a great number of international credit and commerce institutions contradict and undermine such recognition, by means of policies that result in segregation and poverty in the poorest countries. Breaking such logic seems to be the way to enable the existence of conditions of global justice based on terms of reciprocal recognition. A prudential argument is the first step in this process; mid and long-term benefit would be the only rational motivation for international institutions to enable such an openness that would ensure reciprocal recognition. However, this argument is not sufficient, and the objective of a radical inclusion affecting all regions of the planet requires a moral argument based on the idea of equal dignity, inherent to every person. Global justice and its counterpart, local justice, will only be possible through the combination of these two arguments, which would make the existence of a logic of reciprocal recognition possible, thus enabling justice.

    El reconocimiento, en tanto que constitutivo de la subjetividad, es una necesidad básica tanto de las personas como de los Estados. Los términos de relación internacional impuestos por buena parte de los organismos internacionales de crédito y comercio niegan y socavan este reconocimiento a través de políticas que generan exclusión y pobreza en los países más pobres. La ruptura de esta lógica se presenta como un camino que posibilita el surgimiento de condiciones de justicia global basadas en términos de reconocimiento recíproco. Un argumento prudencial oficia como primer paso en este proceso, el beneficio a medio y largo plazo sería la motivación racional para que los organismos internacionales generasen una apertura que permitiese asegurar el reconocimiento recíproco. Sin embargo, este argumento no es suficiente y el objetivo de una inclusión radical que afecte a todas las regiones del planeta requiere un argumento moral basado en la idea de igual dignidad inherente a toda persona. La justicia global y su contraparte de justicia local solamente serán posibles a través de una conjunción de estos dos argumentos que habilitarían la instalación de una lógica de reconocimiento recíproco como posibilitante de la justicia.

  7. Posibilidades educativas de las redes sociales

    OpenAIRE

    Dans Álvarez de Sotomayor, Isabel

    2016-01-01

    [Resumen] El choque entre la realidad personal de la generación que sólo ha conocido un mundo con Internet y las redes sociales al alcance provoca cierta incertidumbre en la educación. Por un lado, se trata de hacerse con las redes sociales sin abandonar los fines educativos y, por otro, de aprovechar los medios para alcanzar metas más altas. En la primera parte se revisa la literatura sobre el tema tratando conceptos como sociedad del conocimiento, tecnología, identidad, web social, redes so...

  8. El higo y sus posibilidades de mercado

    Directory of Open Access Journals (Sweden)

    Sonia Barboza Flores

    2008-04-01

    Full Text Available Este proyecto tuvo como objetivo general “promover la diversificación agrícola del país mediante la generación de tecnologías para la producción e industrialización del cultivo del higo (Ficus carica, así como el establecimiento de nuevas alternativas de mercados y comercialización del producto, con el fin de mejorar las condiciones de vida de los productores”. Como parte de este se procuró el cumplimiento de objetivos específicos como el de “contar con información sobre el estado de la oferta y de la demanda de higo en el país, así como el comportamiento de los precios y de los canales de comercialización existentes” y, también, “ recopilar información sobre la opinión de los consumidores con respecto a las características sensoriales de los productos elaborados a base de higo por el Centro de Investigación en Gestión Agroindustrial, así como medir la eventual intención de compra”.Para estos efectos, se evaluaron distintos factores relacionados con la producción nacional y el uso actual del fruto en su estado fresco y procesado. Además, tomando como base el desarrollo de dos nuevos productos procesados, se hace una evaluación de estos para determinar la aceptación del producto en un mercado regional y para determinar los posibles ajustes que deban hacerse en la formulación del producto.

  9. Criterio y posibilidades del implante celular

    Directory of Open Access Journals (Sweden)

    Beatriz Pelacho

    2008-01-01

    Full Text Available Cada año mueren en Europa y EE.UU. como consecuencia de las enfermedades cardíacas más de medio millón de personas. Este alto índice de mortalidad se debe principalmente a la isquemia, responsable del daño cardíaco y de la consecuente pérdida de cardiomiocitos. Aunque algunos grupos investigadores han indicado la existencia de células progenitoras cardíacas en el corazón, el miocardio adulto no es capaz de regenerarse de modo efectivo, siendo su pérdida prácticamente irreversible. Hasta el momento, la única terapia disponible ha estado basada en el empleo de fármacos, los cuales han tenido un efecto paliativo más que curativo, siendo necesario en los casos más graves el trasplante de corazón. Debido a que las opciones de tratamiento son muy limitadas, la última meta sería prevenir estas complicaciones mediante la regeneración de la zona dañada, cuando el daño se produce. El trasplante de células madre o progenitoras es la aproximación del siglo XXI que ofrece una opción terapéutica para la regeneración y recuperación del corazón.

  10. Las posibilidades de la época

    Directory of Open Access Journals (Sweden)

    Sergio Delgado

    2008-07-01

    Full Text Available Una imagen insiste : un muchacho, un hombre –el hijo del poeta–, de unos treinta años, sube al colectivo que va de Santa Fe a Rincón, con su hijo pequeño –el nieto del poeta–, de unos tres o cuatro años, una noche de invierno. Es una imagen que no vi con mis propios ojos, que me llega de manera indirecta, en el relato de alguien que sí estaba en ese momento en el colectivo, no hace mucho tiempo, cosa de meses, de un año como mucho. Llega hasta mí, entonces, por el relato de este testigo, y me...

  11. Photonic bandgap fiber lasers and multicore fiber lasers for next generation high power lasers

    DEFF Research Database (Denmark)

    Shirakawa, A.; Chen, M.; Suzuki, Y.

    2014-01-01

    Photonic bandgap fiber lasers are realizing new laser spectra and nonlinearity mitigation that a conventional fiber laser cannot. Multicore fiber lasers are a promising tool for power scaling by coherent beam combination. © 2014 OSA....

  12. Laser in operative dentistry

    Directory of Open Access Journals (Sweden)

    E. Yasini

    1994-06-01

    Full Text Available Today laser has a lot of usage in medicine and dentistry. In the field of dentistry, laser is used in soft tissue surgery, sterilization of canals (in root canal therapy and in restorative dentistry laser is used for cavity preparation, caries removal, sealing the grooves (in preventive dentistry, etching enamel and dentin, composite polymerization and removal of tooth sensitivity. The use of Co2 lasers and Nd: YAG for cavity preparation, due to creating high heat causes darkness and cracks around the region of laser radiation. Also due to high temperature of these lasers, pulp damage is inevitable. So today, by using the Excimer laser especially the argon floride type with a wavelength of 193 nm, the problem of heat stress have been solved, but the use of lasers in dentistry, especially for cavity preparation needs more researches and evaluations.

  13. Laser for fusion energy

    International Nuclear Information System (INIS)

    Holzrichter, J.F.

    1995-01-01

    Solid state lasers have proven to be very versatile tools for the study and demonstration of inertial confinement fusion principles. When lasers were first contemplated to be used for the compression of fusion fuel in the late 1950s, the laser output energy levels were nominally one joule and the power levels were 10 3 watts (pulse duration's of 10 -3 sec). During the last 25 years, lasers optimized for fusion research have been increased in power to typically 100,000 joules with power levels approaching 10 14 watts. As a result of experiments with such lasers at many locations, DT target performance has been shown to be consistent with high gain target output. However, the demonstration of ignition and gain requires laser energies of several megajoules. Laser technology improvements demonstrated over the past decade appear to make possible the construction of such multimegajoule lasers at affordable costs. (author)

  14. Radiological protection against lasers

    Energy Technology Data Exchange (ETDEWEB)

    Ballereau, P

    1974-04-01

    A brief description of the biological effects of laser beams is followed by a review of the factors involved in eye and skin damage (factors linked with the nature of lasers and those linked with the organ affected) and a discussion of the problems involved in the determination of threshold exposure levels. Preventive measures are recommended, according to the type of laser (high-energy pulse laser, continuous laser, gas laser). No legislation on the subject exists in France or in Europe. Types of lasers marketed, threshold exposure levels for eye and skin, variations of admissible exposure levels according to wavelength, etc. are presented in tabular form. Nomogram for determination of safe distance for direct vision of a laser is included.

  15. Advances in Fiber Lasers

    National Research Council Canada - National Science Library

    Morse, T

    1999-01-01

    Most of the time of this contract has been devoted toward improvements in optical fiber lasers and toward gathering experience to improve our program in high power, cladding pumped optical fiber lasers...

  16. Laser Processing and Chemistry

    CERN Document Server

    Bäuerle, Dieter

    2011-01-01

    This book gives an overview of the fundamentals and applications of laser-matter interactions, in particular with regard to laser material processing. Special attention is given to laser-induced physical and chemical processes at gas-solid, liquid-solid, and solid-solid interfaces. Starting with the background physics, the book proceeds to examine applications of lasers in “standard” laser machining and laser chemical processing (LCP), including the patterning, coating, and modification of material surfaces. This fourth edition has been enlarged to cover the rapid advances in the understanding of the dynamics of materials under the action of ultrashort laser pulses, and to include a number of new topics, in particular the increasing importance of lasers in various different fields of surface functionalizations and nanotechnology. In two additional chapters, recent developments in biotechnology, medicine, art conservation and restoration are summarized. Graduate students, physicists, chemists, engineers, a...

  17. Fiber Laser Array

    National Research Council Canada - National Science Library

    Simpson, Thomas

    2002-01-01

    ...., field-dependent, loss within the coupled laser array. During this program, Jaycor focused on the construction and use of an experimental apparatus that can be used to investigate the coherent combination of an array of fiber lasers...

  18. ISTEF Laser Radar Program

    National Research Council Canada - National Science Library

    Stryjewski, John

    1998-01-01

    The BMDO Innovative Science and Technology Experimentation Facility (BMDO/ISTEF) laser radar program is engaged in an ongoing program to develop and demonstrate advanced laser radar concepts for Ballistic Missile Defense (BMD...

  19. Wavelength sweepable laser source

    DEFF Research Database (Denmark)

    2014-01-01

    Wavelength sweepable laser source is disclosed, wherein the laser source is a semiconductor laser source adapted for generating laser light at a lasing wavelength. The laser source comprises a substrate, a first reflector, and a second reflector. The first and second reflector together defines...... and having a rest position, the second reflector and suspension together defining a microelectromechanical MEMS oscillator. The MEMS oscillator has a resonance frequency and is adapted for oscillating the second reflector on either side of the rest position.; The laser source further comprises electrical...... connections adapted for applying an electric field to the MEMS oscillator. Furthermore, a laser source system and a method of use of the laser source are disclosed....

  20. Laser surgery - skin

    Science.gov (United States)

    ... Bleeding Problem not going away Infection Pain Scarring Skin color changes Some laser surgery is done when you are asleep and ... TG, Elston DM, eds. Andrews' Diseases of the Skin: Clinical ... lasers, lights, and tissue interactions. In: Hruza GJ, Avram ...

  1. Laser in operative dentistry

    OpenAIRE

    E. Yasini; Gh. Rahbari; A. Matorian

    1994-01-01

    Today laser has a lot of usage in medicine and dentistry. In the field of dentistry, laser is used in soft tissue surgery, sterilization of canals (in root canal therapy) and in restorative dentistry laser is used for cavity preparation, caries removal, sealing the grooves (in preventive dentistry), etching enamel and dentin, composite polymerization and removal of tooth sensitivity. The use of Co2 lasers and Nd: YAG for cavity preparation, due to creating high heat causes darkness and cracks...

  2. Tunable laser optics

    CERN Document Server

    Duarte, FJ

    2015-01-01

    This Second Edition of a bestselling book describes the optics and optical principles needed to build lasers. It also highlights the optics instrumentation necessary to characterize laser emissions and focuses on laser-based optical instrumentation. The book emphasizes practical and utilitarian aspects of relevant optics including the essential theory. This revised, expanded, and improved edition contains new material on tunable lasers and discusses relevant topics in quantum optics.

  3. Laser cutting system

    Science.gov (United States)

    Dougherty, Thomas J

    2015-03-03

    A workpiece cutting apparatus includes a laser source, a first suction system, and a first finger configured to guide a workpiece as it moves past the laser source. The first finger includes a first end provided adjacent a point where a laser from the laser source cuts the workpiece, and the first end of the first finger includes an aperture in fluid communication with the first suction system.

  4. Application of Various Lasers to Laser Trimming Resistance System

    Institute of Scientific and Technical Information of China (English)

    SUN Ji-feng

    2007-01-01

    Though the laser trimming resistance has been an old laser machining industry for over 30 years, the development of technology brings new alternative lasers which can be used for the traditional machining. The paper describes application of various lasers to laser trimming resistance system including early traditional krypton arc lamp pumped Nd:YAG to laser, modern popular diode pumped solid state laser and the present advanced harmonic diode pumped solid state laser. Using the new alternative lasers in the laser trimming resistance system can dramatically improve the yields and equipment performance.

  5. Laser technologies for laser accelerators. Annual report

    International Nuclear Information System (INIS)

    1985-01-01

    The primary result of the work reported is the determination of laser system architectures that satsify the requirements of high luminosity, high energy (about 1 TeV), electron accelerators. It has been found that high laser efficiency is a very hard driver for these accelerators as the total average laser output optical power is likely to fall above 10 MW. The luminosity requires rep rates in the kHz range, and individual pulse lengths in the 1-10 psec range are required to satisfy acceleration gradient goals. CO 2 and KrF lasers were chosen for study because of their potential to simultaneously satisfy the given requirements. Accelerator luminosity is reviewed, and requirements on laser system average power and rep rate are determined as a function of electron beam bunch parameters. Laser technologies are reviewed, including CO 2 , excimers, solid state, and free electron lasers. The proposed accelerator mechanisms are summarized briefly. Work on optical transport geometries for near and far field accelerators are presented. Possible exploitation of the CO 2 and DrF laser technology to generate the required pulse lengths, rep rates, and projected efficiencies is illustrated and needed development work is suggested. Initial efforts at developing a 50 GeV benchmark conceptual design and a 100 MeV demonstration experiment conceptual design are presented

  6. Laser induced pyrolysis techniques

    International Nuclear Information System (INIS)

    Vanderborgh, N.E.

    1976-01-01

    The application of laser pyrolysis techniques to the problems of chemical analysis is discussed. The processes occurring during laser pyrolysis are first briefly reviewed. The problems encountered in laser pyrolysis gas chromatography are discussed using the analysis of phenanthrene and binary hydrocarbons. The application of this technique to the characterization of naturally occurring carbonaceous material such as oil shales and coal is illustrated

  7. Solar pumped laser

    Science.gov (United States)

    Lee, J. H.; Hohl, F.; Weaver, W. R. (Inventor)

    1984-01-01

    A solar pumped laser is described in which the lasant is a gas that will photodissociate and lase when subjected to sunrays. Sunrays are collected and directed onto the gas lasant to cause it to lase. Applications to laser propulsion and laser power transmission are discussed.

  8. Introducing the Yellow Laser

    Science.gov (United States)

    Lincoln, James

    2018-01-01

    The author has acquired a yellow laser with the specific wavelength of 589 nm. Because this is the first time such a laser has been discussed in this journal, I feel it is appropriate to provide a discussion of its function and capabilities. Normal laser safety should be employed, such as not pointing it into eyes or at people, and using eye…

  9. Coatings for laser fusion

    International Nuclear Information System (INIS)

    Lowdermilk, W.H.

    1981-01-01

    Optical coatings are used in lasers systems for fusion research to control beam propagation and reduce surface reflection losses. The performance of coatings is important in the design, reliability, energy output, and cost of the laser systems. Significant developments in coating technology are required for future lasers for fusion research and eventual power reactors

  10. uv dye lasers

    International Nuclear Information System (INIS)

    Abakumov, G.A.; Fadeev, V.V.; Khokhlov, R.V.; Simonov, A.P.

    1975-01-01

    The most important property of visible dye lasers, that is, continuous wavelength tuning, stimulated the search for dyes capable to lase in uv. They were found in 1968. Now the need for tunable uv lasers for applications in spectroscopy, photochemistry, isotope separation, remote air and sea probing, etc. is clearly seen. A review of some recent advances in uv dye lasers is reviewed

  11. LaserFest Celebration

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Alan Chodos; Elizabeth A. Rogan

    2011-08-25

    LaserFest was the yearlong celebration, during 2010, of the 50th anniversary of the demonstration of the first working laser. The goals of LaserFest were: to highlight the impact of the laser in its manifold commercial, industrial and medical applications, and as a tool for ongoing scientific research; to use the laser as one example that illustrates, more generally, the route from scientific innovation to technological application; to use the laser as a vehicle for outreach, to stimulate interest among students and the public in aspects of physical science; to recognize and honor the pioneers who developed the laser and its many applications; to increase awareness among policymakers of the importance of R&D funding as evidenced by such technology as lasers. One way in which LaserFest sought to meet its goals was to encourage relevant activities at a local level all across the country -- and also abroad -- that would be identified with the larger purposes of the celebration and would carry the LaserFest name. Organizers were encouraged to record and advertise these events through a continually updated web-based calendar. Four projects were explicitly detailed in the proposals: 1) LaserFest on the Road; 2) Videos; 3) Educational material; and 4) Laser Days.

  12. Laser beam cutting method. Laser ko ni yoru kaitai koho

    Energy Technology Data Exchange (ETDEWEB)

    Kutsumizu, A. (Obayashi Corp., Osaka (Japan))

    1991-07-01

    In this special issue paper concerning the demolition of concrete structures, was introduced a demolition of concrete structures using laser, of which practical application is expected due to the remarkable progress of generating power and efficiency of laser radiator. The characteristics of laser beam which can give a temperature of one million centigrade at the irradiated spot, the laser radiator consisting of laser medium, laser resonator and pumping apparatus, and the laser kinds for working, such as CO{sub 2} laser, YAG laser and CO laser, were described. The basic constitution of laser cutting equipment consisting of large generating power radiator, beam transmitter, beam condenser, and nozzle for working was also illustrated. Furthermore, strong and weak points in the laser cutting for concrete and reinforcement were enumerated. Applications of laser to cutting of reinforced and unreinforced concrete constructions were shown, and the concept and safety measure for application of laser to practical demolition was discussed. 5 refs., 8 figs.

  13. Introduction to laser technology

    CERN Document Server

    Hitz, C Breck; Hecht, Jeff; Hitz, C Breck; John Wiley & Sons

    2001-01-01

    Electrical Engineering Introduction to Laser Technology , Third Edition. Would you like to know how a laser works, and how it can be modified for your own specific tasks? This intuitive third edition-previously published as Understanding Laser Technology , First and Second Editions-introduces engineers, scientists, technicians, and novices alike to the world of modern lasers, without delving into the mathematical details of quantum electronics. It is the only introductory text on the market today that explains the underlying physics and engineering applicable to all lasers. A unique combinatio.

  14. Quantum well lasers

    CERN Document Server

    Zory, Jr, Peter S; Kelley, Paul

    1993-01-01

    This book provides the information necessary for the reader to achieve a thorough understanding of all aspects of QW lasers - from the basic mechanism of optical gain, through the current technolgoical state of the art, to the future technologies of quantum wires and quantum dots. In view of the growing importance of QW lasers, this book should be read by all those with an active interest in laser science and technology, from the advanced student to the experienced laser scientist.* The first comprehensive book-length treatment of quantum well lasers* Provides a detailed treatment

  15. Coherent laser beam combining

    CERN Document Server

    Brignon, Arnaud

    2013-01-01

    Recently, the improvement of diode pumping in solid state lasers and the development of double clad fiber lasers have allowed to maintain excellent laser beam quality with single mode fibers. However, the fiber output power if often limited below a power damage threshold. Coherent laser beam combining (CLBC) brings a solution to these limitations by identifying the most efficient architectures and allowing for excellent spectral and spatial quality. This knowledge will become critical for the design of the next generation high-power lasers and is of major interest to many industrial, environme

  16. The laser thermonuclear fusion

    International Nuclear Information System (INIS)

    Coutant, J.; Dautray, R.; Decroisette, M.; Watteau, J.P.

    1987-01-01

    Principle of the thermonuclear fusion by inertial confinement: required characteristics of the deuterium-tritium plasma and of the high power lasers to be used Development of high power lasers: active media used; amplifiers; frequency conversion; beam quality; pulse conditioning; existing large systems. The laser-matter interaction: collision and collective interaction of the laser radiation with matter; transport of the absorbed energy; heating and compression of deuterium-tritium; diagnoses and their comparison with the numerical simulation of the experiment; performances. Conclusions: difficulties to overcome; megajoule lasers; other energy source: particles beams [fr

  17. Laser Cutting, Development Trends

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    1999-01-01

    In this paper a short review of the development trends in laser cutting will be given.The technology, which is the fastest expanding industrial production technology will develop in both its core market segment: Flat bed cutting of sheet metal, as it will expand in heavy industry and in cutting...... of 3-dimensional shapes.The CO2-laser will also in the near future be the dominating laser source in the market, although the new developments in ND-YAG-lasers opens for new possibilities for this laser type....

  18. Lasers in space.

    CSIR Research Space (South Africa)

    Michaelis, MM

    2008-04-01

    Full Text Available cube, laser beam reflectors, placed on the Moon half a century ago. These early achievements will soon be followed by a plethora of experiments involving lasers in low earth orbit (LEO) or at Lagrange points. And not much later, laser communications... will stretch out as far as Mars and beyond. One important low Earth orbit (LEO) application is the removal of space debris by Earth based or LEO relayed lasers as promoted by Phipps et al.3. Another is military communication. The prominent L1 laser space...

  19. Tunable laser applications

    CERN Document Server

    Duarte, FJ

    2008-01-01

    Introduction F. J. Duarte Spectroscopic Applications of Tunable Optical Parametric Oscillators B. J. Orr, R. T. White, and Y. He Solid-State Dye Lasers Costela, I. García-Moreno, and R. Sastre Tunable Lasers Based on Dye-Doped Polymer Gain Media Incorporating Homogeneous Distributions of Functional Nanoparticles F. J. Duarte and R. O. James Broadly Tunable External-Cavity Semiconductor Lasers F. J. Duarte Tunable Fiber Lasers T. M. Shay and F. J. Duarte Fiber Laser Overview and Medical Applications

  20. New solid laser: Ceramic laser. From ultra stable laser to ultra high output laser

    International Nuclear Information System (INIS)

    Ueda, Kenichi

    2006-01-01

    An epoch-making solid laser is developed. It is ceramic laser, polycrystal, which is produced as same as glass and shows ultra high output. Ti 3+ :Al 2 O 3 laser crystal and the CPA (chirped pulse amplification) technique realized new ultra high output lasers. Japan has developed various kinds of ceramic lasers, from 10 -2 to 67 x 10 3 w average output, since 1995. These ceramic lasers were studied by gravitational radiation astronomy. The scattering coefficient of ceramic laser is smaller than single crystals. The new fast ignition method is proposed by Institute of Laser Engineering of Osaka University, Japan. Ultra-intense short pulse laser can inject the required energy to the high-density imploded core plasma within the core disassembling time. Ti 3+ :Al 2 O 3 crystal for laser, ceramic YAG of large caliber for 100 kW, transparent laser ceramic from nano-crystals, crystal grain and boundary layer between grains, the scattering coefficient of single crystal and ceramic, and the derived release cross section of Yb:YAG ceramic are described. (S.Y.)

  1. Advanced lasers for fusion

    International Nuclear Information System (INIS)

    Krupke, W.F.; George, E.V.; Haas, R.A.

    1979-01-01

    Laser drive systems' performance requirements for fusion reactors are developed following a review of the principles of inertial confinement fusion and of the technical status of fusion research lasers (Nd:glass; CO 2 , iodine). These requirements are analyzed in the context of energy-storing laser media with respect to laser systems design issues: optical damage and breakdown, medium excitation, parasitics and superfluorescence depumping, energy extraction physics, medium optical quality, and gas flow. Three types of energy-storing laser media of potential utility are identified and singled out for detailed review: (1) Group VI atomic lasers, (2) rare earth solid state hybrid lasers, and (3) rare earth molecular vapor lasers. The use of highly-radiative laser media, particularly the rare-gas monohalide excimers, are discussed in the context of short pulse fusion applications. The concept of backward wave Raman pulse compression is considered as an attractive technique for this purpose. The basic physics and device parameters of these four laser systems are reviewed and conceptual designs for high energy laser systems are presented. Preliminary estimates for systems efficiencies are given. (Auth.)

  2. Micromachining with copper lasers

    Science.gov (United States)

    Knowles, Martyn R. H.; Bell, Andy; Foster-Turner, Gideon; Rutterford, Graham; Chudzicki, J.; Kearsley, Andrew J.

    1997-04-01

    In recent years the copper laser has undergone extensive development and has emerged as a leading and unique laser for micromachining. The copper laser is a high average power (10 - 250 W), high pulse repetition rate (2 - 32 kHz), visible laser (511 nm and 578 nm) that produces high peak power (typically 200 kW), short pulses (30 ns) and very good beam quality (diffraction limited). This unique set of laser parameters results in exceptional micro-machining in a wide variety of materials. Typical examples of the capabilities of the copper laser include the drilling of small holes (10 - 200 micrometer diameter) in materials as diverse as steel, ceramic, diamond and polyimide with micron precision and low taper (less than 1 degree) cutting and profiling of diamond. Application of the copper laser covers the electronic, aerospace, automotive, nuclear, medical and precision engineering industries.

  3. Laser Applications in Orthodontics

    Science.gov (United States)

    Heidari, Somayeh; Torkan, Sepideh

    2013-01-01

    A laser is a collimated single wavelength of light which delivers a concentrated source of energy. Soon after different types of lasers were invented, investigators began to examine the effects of different wavelengths of laser energy on oral tissues, routine dental procedures and experimental applications. Orthodontists, along with other specialist in different fields of dentistry, can now benefit from several different advantages that lasers provide during the treatment process, from the beginning of the treatment, when separators are placed, to the time of resin residues removal from the tooth surface at the end of orthodontic treatment. This article outlines some of the most common usages of laser beam in orthodontics and also provides a comparison between laser and other conventional method that were the standard of care prior to the advent of laser in this field. PMID:25606324

  4. ORION laser target diagnostics

    International Nuclear Information System (INIS)

    Bentley, C. D.; Edwards, R. D.; Andrew, J. E.; James, S. F.; Gardner, M. D.; Comley, A. J.; Vaughan, K.; Horsfield, C. J.; Rubery, M. S.; Rothman, S. D.; Daykin, S.; Masoero, S. J.; Palmer, J. B.; Meadowcroft, A. L.; Williams, B. M.; Gumbrell, E. T.; Fyrth, J. D.; Brown, C. R. D.; Hill, M. P.; Oades, K.

    2012-01-01

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics.

  5. ORION laser target diagnostics.

    Science.gov (United States)

    Bentley, C D; Edwards, R D; Andrew, J E; James, S F; Gardner, M D; Comley, A J; Vaughan, K; Horsfield, C J; Rubery, M S; Rothman, S D; Daykin, S; Masoero, S J; Palmer, J B; Meadowcroft, A L; Williams, B M; Gumbrell, E T; Fyrth, J D; Brown, C R D; Hill, M P; Oades, K; Wright, M J; Hood, B A; Kemshall, P

    2012-10-01

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics.

  6. Robot-laser system

    International Nuclear Information System (INIS)

    Akeel, H.A.

    1987-01-01

    A robot-laser system is described for providing a laser beam at a desired location, the system comprising: a laser beam source; a robot including a plurality of movable parts including a hollow robot arm having a central axis along which the laser source directs the laser beam; at least one mirror for reflecting the laser beam from the source to the desired location, the mirror being mounted within the robot arm to move therewith and relative thereto to about a transverse axis that extends angularly to the central axis of the robot arm; and an automatic programmable control system for automatically moving the mirror about the transverse axis relative to and in synchronization with movement of the robot arm to thereby direct the laser beam to the desired location as the arm is moved

  7. Laser safety in dentistry

    Science.gov (United States)

    Wigdor, Harvey A.

    1997-05-01

    One of the major causes of anxiety in the dental clinic is the dental handpiece. Because dentists wish to provide a method which can replace the drill there has often been a premature use of the laser in dentistry. Various lasers have been introduced into the clinic before research has shown the laser used is of clinical benefit. Any new treatment method must not compromise the health of the patient being treated. Thus a method of evaluating the clinical abilities of dentists and their understanding the limitations of the laser used must be developed. Dentist must be trained in the basic interaction of the laser on oral tissues. The training has to concentrate on the variation of the laser wavelength absorption in the different tissues of the oral cavity. Because of the differences in the optical properties of these tissues great care must be exercised by practitioners using lasers on patients.

  8. Lasers in materials science

    CERN Document Server

    Ossi, Paolo; Zhigilei, Leonid

    2014-01-01

    This book covers various aspects of lasers in materials science, including a comprehensive overview on basic principles of laser-materials interactions and applications enabled by pulsed laser systems.  The material is organized in a coherent way, providing the reader with a harmonic architecture. While systematically covering the major current and emerging areas of lasers processing applications, the Volume provides examples of targeted modification of material properties achieved through careful control of the processing conditions and laser irradiation parameters. Special emphasis is placed on specific strategies aimed at nanoscale control of material structure and properties to match the stringent requirements of modern applications.  Laser fabrication of novel nanomaterials, which expands to the domains of photonics, photovoltaics, sensing, and biomedical applications, is also discussed in the Volume. This book assembles chapters based on lectures delivered at the Venice International School on Lasers...

  9. Alternate laser fusion drivers

    International Nuclear Information System (INIS)

    Pleasance, L.D.

    1979-11-01

    One objective of research on inertial confinement fusion is the development of a power generating system based on this concept. Realization of this goal will depend on the availability of a suitable laser or other system to drive the power plant. The primary laser systems used for laser fusion research, Nd 3+ : Glass and CO 2 , have characteristics which may preclude their use for this application. Glass lasers are presently perceived to be incapable of sufficiently high average power operation and the CO 2 laser may be limited by and issues associated with target coupling. These general perceptions have encouraged a search for alternatives to the present systems. The search for new lasers has been directed generally towards shorter wavelengths; most of the new lasers discovered in the past few years have been in the visible and ultraviolet region of the spectrum. Virtually all of them have been advocated as the most promising candidate for a fusion driver at one time or another

  10. Flexible Laser Metal Cutting

    DEFF Research Database (Denmark)

    Villumsen, Sigurd; Jørgensen, Steffen Nordahl; Kristiansen, Morten

    2014-01-01

    This paper describes a new flexible and fast approach to laser cutting called ROBOCUT. Combined with CAD/CAM technology, laser cutting of metal provides the flexibility to perform one-of-a-kind cutting and hereby realises mass production of customised products. Today’s laser cutting techniques...... possess, despite their wide use in industry, limitations regarding speed and geometry. Research trends point towards remote laser cutting techniques which can improve speed and geometrical freedom and hereby the competitiveness of laser cutting compared to fixed-tool-based cutting technology...... such as punching. This paper presents the concepts and preliminary test results of the ROBOCUT laser cutting technology, a technology which potentially can revolutionise laser cutting....

  11. Lasers: principles, applications and energetic measures

    International Nuclear Information System (INIS)

    Subran, C.; Sagaut, J.; Lapointe, S.

    2009-01-01

    After having recalled the principles of a laser and the properties of the laser beam, the authors describe the following different types of lasers: solid state lasers, fiber lasers, semiconductor lasers, dye lasers and gas lasers. Then, their applications are given. Very high energy lasers can reproduce the phenomenon of nuclear fusion of hydrogen atoms. (O.M.)

  12. Lasers in space

    Science.gov (United States)

    Michaelis, M. M.; Forbes, A.; Bingham, R.; Kellett, B. J.; Mathye, A.

    2008-05-01

    A variety of laser applications in space, past, present, future and far future are reviewed together with the contributions of some of the scientists and engineers involved, especially those that happen to have South African connections. Historically, two of the earliest laser applications in space, were atmospheric LIDAR and lunar ranging. These applications involved atmospheric physicists, several astronauts and many of the staff recruited into the Soviet and North American lunar exploration programmes. There is a strong interest in South Africa in both LIDAR and lunar ranging. Shortly after the birth of the laser (and even just prior) theoretical work on photonic propulsion and space propulsion by laser ablation was initiated by Georgii Marx, Arthur Kantrowitz and Eugen Saenger. Present or near future experimental programs are developing in the following fields: laser ablation propulsion, possibly coupled with rail gun or gas gun propulsion; interplanetary laser transmission; laser altimetry; gravity wave detection by space based Michelson interferometry; the de-orbiting of space debris by high power lasers; atom laser interferometry in space. Far future applications of laser-photonic space-propulsion were also pioneered by Carl Sagan and Robert Forward. They envisaged means of putting Saenger's ideas into practice. Forward also invented a laser based method for manufacturing solid antimatter or SANTIM, well before the ongoing experiments at CERN with anti-hydrogen production and laser-trapping. SANTIM would be an ideal propellant for interstellar missions if it could be manufactured in sufficient quantities. It would be equally useful as a power source for the transmission of information over light year distances. We briefly mention military lasers. Last but not least, we address naturally occurring lasers in space and pose the question: "did the Big Bang lase?"

  13. Laser system using ultra-short laser pulses

    Science.gov (United States)

    Dantus, Marcos [Okemos, MI; Lozovoy, Vadim V [Okemos, MI; Comstock, Matthew [Milford, MI

    2009-10-27

    A laser system using ultrashort laser pulses is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal.

  14. Corrida em piscina funda: limites e possibilidades para o alto desempenho Velocidad en piscina de profundidad: límites y posibilidades para un alto desempeño Deep water running: limits and possibilities for high performance

    Directory of Open Access Journals (Sweden)

    Leonardo Alexandre Peyré-Tartaruga

    2006-10-01

    Full Text Available O objetivo deste estudo foi analisar os limites e possibilidades da utilização da corrida em piscina funda no treinamento de corredores de rendimento. Além disso, são discutidas as respostas agudas submáximas, máximas e crônicas, do ponto de vista fisiológico e biomecânico entre a corrida em terra e em piscina funda. As respostas máximas de freqüência cardíaca e consumo de oxigênio são menores no exercício aquático do que na corrida terrestre. Dados experimentais sugerem o uso do treinamento de corrida em piscina funda para corredores de rendimento; contudo, essas evidências são limitadas para treinamentos de até 10 semanas.El objetivo de este estudio ha sido el de analizar los límites y posibilidades de la utilización de carreras de velocidad en piscina de profundidad durante el entrenamiento de velocista de rendimiento. Además de esto, son discutidas las respuestas agudas submáximas, máximas y crónicas, bajo el punto de vista fisiológico y biomecánico entre la carrera en tierra y en piscina profunda. Las respuestas máximas de frecuencia cardíaca y consumo de oxígeno son menores en el ejercicio acuático que en la de tierra. Datos experimentales sugieren el uso de entrenamiento de carrera en piscina profunda para velocistas de rendimiento, sin embargo estas evidencias son limitadas a entrenamientos de hasta 10 semanas.The purpose of this study was to analyze the limits and possibilities of deep water running on training of performance runners. Besides, it has been discussed the submaximal acute, maximal acute and chronical responses, following physiological and biomechanical aspects between running on land and deep water running. Heart rate and oxygen uptake's maximal responses are lower in aquatic exercise than in running on land. Experimental evidences suggest the deep water running training for performance athletes, but these studies are limited in training program until ten weeks.

  15. The possibilities for reuse of steel scrap in order to obtain blades for knives; Posibilidades de reutilización de la chatarra de acero para la obtención de cuchillas para cortar

    Energy Technology Data Exchange (ETDEWEB)

    Štrbaca, N.; Markovića, I.; Mitovskia, A.; Balanovića, L.; Živkovića, D.; Grekulović, V.

    2017-09-01

    The purpose of this study is to determine fracture toughness of Resistance Spot Welded (RSW) Dual Phase (DP) steels. RSW of galvanized and ungalvanized DP 450 steel sheets was carried out on spot welding machine. Fracture toughness of RSW joints of galvanized and ungalvanized DP 450 steel sheets was calculated from tensile-shear tests. New empirical equations were developed using Least Squares Method (LSM) between energy release rate, fracture toughness and critical crack size depending on the relationship between hardness and fracture toughness values. Results indicated that fracture toughness of joints welded by using RSW increased exponentially while the hardness decreased. In addition, fracture toughness and energy release rate of RSW galvanized DP 450 steel sheets were lower compared to RSW ungalvanized DP 450 steel sheets which had approximately the same hardness. [Spanish] El trabajo presenta los resultados de la caracterización de diversos tipos de aceros que han llegado al final de su ciclo de vida útil, y de los que se desconocía su composición química, propiedades mecánicas y tratamiento termomecánico aplicado previamente. El estudio se realizó con el objetivo de analizar las posibilidades de reutilización de algunos de estos materiales en aplicaciones agrícolas e industriales, obteniendo hojas de corte. Las formas exigidas a las hojas de corte se consiguieron aplicando diversos tipos de tratamientos termomecánicos. El análisis químico de la chatarra de acero de acero se realizó utilizando Energías Dispersivas de Rayos X. La microestructura se estudió utilizando Microscopía Óptica y Microscopía Electrónica de Barrido. La dureza de la chatarra de acero y de las cuchillas obtenidas se midió utilizando la escala Rockwell C. Los valores de dureza de las cuchillas obtenidas indican una buena selección de los productos finales de acero.

  16. Designing of Raman laser

    International Nuclear Information System (INIS)

    Zidan, M. D.; Al-Awad, F.; Alsous, M. B.

    2005-01-01

    In this work, we describe the design of the Raman laser pumped by Frequency doubled Nd-YAG laser (λ=532 nm) to generate new laser wavelengths by shifting the frequency of the Nd-YAG laser to Stokes region (λ 1 =683 nm, λ 2 =953.6 nm, λ 3 =1579.5 nm) and Antistokes region (λ ' 1 =435 nm, λ ' 2 =369.9 nm, λ ' 3=319.8 nm). Laser resonator has been designed to increase the laser gain. It consists of two mirrors, the back mirror transmits the pump laser beam (λ=532 nm) through the Raman tube and reflects all other generated Raman laser lines. Four special front mirrors were made to be used for the four laser lines λ 1 =683 nm, λ 2 =953.6 nm and λ ' 1 = 435 nm, λ ' 2 =369.9 nm. The output energy for the lines υ 1 s, υ 2 s, υ 1 as,υ 2 as was measured. The output energy of the Raman laser was characterized for different H 2 pressure inside the tube. (Author)

  17. Laser program overview

    International Nuclear Information System (INIS)

    Storm, E.; Coleman, L.W.

    1985-01-01

    The objectives of the Lawrence Livermore National Laboratory Laser Fusion program are to understand and develop the science and technology of inertial confinement fusion (ICF), and to utilize ICF in short- and long-term military applications, and, in the long-term, as a candidate for central-station civilian power generation. In 1984, using the Novette laser system, the authors completed experiments showing the very favorable scaling of laser-plama interactions with short-wavelength laser light. Their Novette experiments have unequivocally shown that short laser wavelength, i.e., less than 1 μm, is required to provide the drive necessary for efficient compression, ignition, and burn of DT fusion fuel. In other experiments with Novette, the authors made the first unambiguous observation of amplified spontaneous emission in the soft x-ray regime. The authors also conducted military applications and weapons physics experiments, which they discuss in detail in the classified volume of our Laser Program Annual Report. In the second thrust, advanced laser studies, they develop and test the concepts, components, and materials for present and future laser systems. Over the years, this has meant providing the technology base and scientific advances necessary to construct and operate a succession of six evermore-powerful laser systems. The latest of these, Nova, a 100-TW/100-kJ-class laser system, was completed in 1984. The Nd:glass laser continues to be the most effective and versatile tool for ICF and weapons physics because of its scalability in energy, the ability to efficiently convert its 1=μm output to shorter wavelengths, its ability to provide flexible, controlled pulse shaping, and its capability to adapt to a variety of irradiation and focusing geometries. For these reasons, many of our advanced laser studies are in areas appropriate to solid state laser technologies

  18. Laser pumped lasers for isotope separation

    International Nuclear Information System (INIS)

    Fry, S.M.

    1976-01-01

    A study of the isotope separation laser requirements reveals that high pressure polyatomic molecular gas laser pumped lasers can attain the necessary characteristics including tunability, energy output, pulse width, and repetition rate. The results of a search, made for molecules meeting the appropriate requirements for one of several pump schemes utilizing a CO 2 laser and with output in the 12 μm or 16μm wavelength range, are presented. Several methods of pumping are reviewed and two novel pump schemes are presented. A laser pumped laser device design is given, and operation of this device and associated diagnostic equipment is confirmed by repeating experiments in OCS and NH 3 . The results of OCS laser experiments show that an improvement in pump rate and output per unit length is obtained with the device, using a wedged transverse pumping scheme. A new multi-line laser system in NH 3 pumped by a TEA CO 2 laser is reported. More than forty transitions spanning the wavelength range of 9.2 to 13.8 μm are observed and identified. A strong output at 12.08 μm is one of the closest lines yet found to the required laser isotope separation wavelength. Far infrared emission near 65 μm is observed and is responsible for populating levels which lase in pure ammonia near 12.3 μm. Buffer gas (e.g., N 2 or He) pressures of approximately 40--800 torr cause energy transfer by collision-induced rotationaltransitions from the pumped antisymmetric to the lasing symmetric levels in the nu 2 = 1 band of ammonia. Most of the observed lines are aP(J,K) transitions which originate from the nu 2 /sup s/ band. Measurements of the pressure dependence of the laser output shows that some lines lase at pressures greater than one atmosphere. Transient behavior of the 12.08 μm line is calculated from a simplified analytic model and these calculations are compared to the experimental results

  19. Pattern Laser Annealing by a Pulsed Laser

    Science.gov (United States)

    Komiya, Yoshio; Hoh, Koichiro; Murakami, Koichi; Takahashi, Tetsuo; Tarui, Yasuo

    1981-10-01

    Preliminary experiments with contact-type pattern laser annealing were made for local polycrystallization of a-Si, local evaporation of a-Si and local formation of Ni-Si alloy. These experiments showed that the mask patterns can be replicated as annealed regions with a resolution of a few microns on substrates. To overcome shortcomings due to the contact type pattern annealing, a projection type reduction pattern laser annealing system is proposed for resistless low temperature pattern forming processes.

  20. High energy HF pulsed lasers

    International Nuclear Information System (INIS)

    Patterson, E.L.; Gerber, R.A.

    1976-01-01

    Recent experiments show that pulsed HF lasers are capable of producing high energy with good efficiency. Preliminary experiments show that the laser radiation from the high-gain medium can be controlled with a low-power probe laser beam or with low-level feedback. These results indicate that the HF laser may have potential for second-generation laser fusion experiments

  1. Laser Safety Inspection Criteria

    International Nuclear Information System (INIS)

    Barat, K

    2005-01-01

    A responsibility of the Laser Safety Officer (LSO) is to perform laser safety audits. The American National Standard Z136.1 Safe use of Lasers references this requirement in several sections: (1) Section 1.3.2 LSO Specific Responsibilities states under Hazard Evaluation, ''The LSO shall be responsible for hazards evaluation of laser work areas''; (2) Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''; and (3) Appendix D, under Survey and Inspections, it states, ''the LSO will survey by inspection, as considered necessary, all areas where laser equipment is used''. Therefore, for facilities using Class 3B and or Class 4 lasers, audits for laser safety compliance are expected to be conducted. The composition, frequency and rigueur of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms. In many institutions, a sole Laser Safety Officer (LSO) or a number of Deputy LSO's perform these audits. For that matter, there are institutions that request users to perform a self-assessment audit. Many items on the common audit list and the associated findings are subjective because they are based on the experience and interest of the LSO or auditor in particular items on the checklist. Beam block usage is an example; to one set of eyes a particular arrangement might be completely adequate, while to another the installation may be inadequate. In order to provide more consistency, the National Ignition Facility Directorate at Lawrence Livermore National Laboratory (NIF-LLNL) has established criteria for a number of items found on the typical laser safety audit form. These criteria are distributed to laser users, and they serve two broad purposes: first, it gives the user an expectation of what will be reviewed by an auditor, and second, it is an

  2. Single frequency semiconductor lasers

    CERN Document Server

    Fang, Zujie; Chen, Gaoting; Qu, Ronghui

    2017-01-01

    This book systematically introduces the single frequency semiconductor laser, which is widely used in many vital advanced technologies, such as the laser cooling of atoms and atomic clock, high-precision measurements and spectroscopy, coherent optical communications, and advanced optical sensors. It presents both the fundamentals and characteristics of semiconductor lasers, including basic F-P structure and monolithic integrated structures; interprets laser noises and their measurements; and explains mechanisms and technologies relating to the main aspects of single frequency lasers, including external cavity lasers, frequency stabilization technologies, frequency sweeping, optical phase locked loops, and so on. It paints a clear, physical picture of related technologies and reviews new developments in the field as well. It will be a useful reference to graduate students, researchers, and engineers in the field.

  3. Nuclear-pumped lasers

    CERN Document Server

    Prelas, Mark

    2016-01-01

    This book focuses on Nuclear-Pumped Laser (NPL) technology and provides the reader with a fundamental understanding of NPLs, a review of research in the field, and exploration of large scale NPL system design and applications. Early chapters look at the fundamental properties of lasers, nuclear-pumping and nuclear reactions that may be used as drivers for nuclear-pumped lasers. The book goes on to explore the efficient transport of energy from the ionizing radiation to the laser medium and then the operational characteristics of existing nuclear-pumped lasers. Models based on Mathematica, explanations and a tutorial all assist the reader’s understanding of this technology. Later chapters consider the integration of the various systems involved in NPLs and the ways in which they can be used, including beyond the military agenda. As readers will discover, there are significant humanitarian applications for high energy/power lasers, such as deflecting asteroids, space propulsion, power transmission and mining....

  4. Power Laser Ablation Symposia

    CERN Document Server

    Phipps, Claude

    2007-01-01

    Laser ablation describes the interaction of intense optical fields with matter, in which atoms are selectively driven off by thermal or nonthermal mechanisms. The field of laser ablation physics is advancing so rapidly that its principal results are seen only in specialized journals and conferences. This is the first book that combines the most recent results in this rapidly advancing field with authoritative treatment of laser ablation and its applications, including the physics of high-power laser-matter interaction. Many practical applications exist, ranging from inertial confinement fusion to propulsion of aerostats for pollution monitoring to laser ignition of hypersonic engines to laser cleaning nanoscale contaminants in high-volume computer hard drive manufacture to direct observation of the electronic or dissociative states in atoms and molecules, to studying the properties of materials during 200kbar shocks developed in 200fs. Selecting topics which are representative of such a broad field is difficu...

  5. Laser induced nuclear reactions

    International Nuclear Information System (INIS)

    Ledingham, Ken; McCanny, Tom; Graham, Paul; Fang Xiao; Singhal, Ravi; Magill, Joe; Creswell, Alan; Sanderson, David; Allott, Ric; Neely, David; Norreys, Peter; Santala, Marko; Zepf, Matthew; Watts, Ian; Clark, Eugene; Krushelnick, Karl; Tatarakis, Michael; Dangor, Bucker; Machecek, Antonin; Wark, Justin

    1998-01-01

    Dramatic improvements in laser technology since 1984 have revolutionised high power laser technology. Application of chirped-pulse amplification techniques has resulted in laser intensities in excess of 10 19 W/cm 2 . In the mid to late eighties, C. K. Rhodes and K. Boyer discussed the possibility of shining laser light of this intensity onto solid surfaces and to cause nuclear transitions. In particular, irradiation of a uranium target could induce electro- and photofission in the focal region of the laser. In this paper it is shown that μCi of 62 Cu can be generated via the (γ,n) reaction by a laser with an intensity of about 10 19 Wcm -2

  6. Lasers for isotope separation

    International Nuclear Information System (INIS)

    O'Hair, E.A.; Piltch, M.S.

    1976-01-01

    The Los Alamos Scientific Laboratory is conducting research on uranium enrichment. All processes being studied employ uranium molecules and use lasers to provide isotopic selectivity and enrichment. There are four well-defined infrared frequencies and two ultraviolet frequency bands of interest. The infrared frequencies are outside the range of the available lasers and an extensive research and development activity is currently underway. Lasers are available in the uv bands, however, much development work remains. The specification for the commercial uranium enrichment plant lasers will depend upon the results of the current enrichment experiments, the laser capital cost, reliability, and maintenance cost. For the processes under investigation there are specific photon requirements but latitude in how these requirements can be met. The final laser selections for the pilot plant need not be made until the mid-1980's. Between now and that time as extensive as possible a research and development effort will be maintained

  7. Inertial fusion by laser

    International Nuclear Information System (INIS)

    Dautray, R.; Watteau, J.-P.

    1980-01-01

    Following a brief historical survey of research into the effects of interaction of laser with matter, the principles of fusion by inertial confinement are described and the main parameters and possible levels given. The development of power lasers is then discussed with details of performances of the main lasers used in various laboratories, and with an assessment of the respective merits of neodymium glass, carbon dioxide or iodine lasers. The phenomena of laser radiation and its interaction with matter is then described, with emphasis on the results of experiments concerned with target implosion with the object of compressing and heating the mixture of heavy hydrogen and tritium to be ignited. Finally, a review is made of future possibilities opened up by the use of large power lasers which have recently become operational or are being constructed, and the ground still to be covered before a reactor can be produced [fr

  8. Principles of Lasers

    CERN Document Server

    Svelto, Orazio

    2010-01-01

    This new Fifth Edition of Principles of Lasers incorporates corrections to the previous edition. The text’s essential mission remains the same: to provide a wide-ranging yet unified description of laser behavior, physics, technology, and current applications. Dr. Svelto emphasizes the physical rather than the mathematical aspects of lasers, and presents the subject in the simplest terms compatible with a correct physical understanding. Praise for earlier editions: "Professor Svelto is himself a longtime laser pioneer and his text shows the breadth of his broad acquaintance with all aspects of the field … Anyone mastering the contents of this book will be well prepared to understand advanced treatises and research papers in laser science and technology." (Arthur L. Schawlow, 1981 Nobel Laureate in Physics) "Already well established as a self-contained introduction to the physics and technology of lasers … Professor Svelto’s book, in this lucid translation by David Hanna, can be strongly recommended for...

  9. Atomic iodine laser

    International Nuclear Information System (INIS)

    Fisk, G.A.; Gusinow, M.A.; Hays, A.K.; Padrick, T.D.; Palmer, R.E.; Rice, J.K.; Truby, F.K.; Riley, M.E.

    1978-05-01

    The atomic iodine photodissociation laser has been under intensive study for a number of years. The physics associated with this system is now well understood and it is possible to produce a 0.1 nsec (or longer) near-diffraction-limited laser pulse which can be amplified with negligible temporal distortion and little spatial deformation. The output of either a saturated or unsaturated amplifier consists of a high-fidelity near-diffraction-limited, energetic laser pulse. The report is divided into three chapters. Chapter 1 is a survey of the important areas affecting efficient laser operation and summarizes the findings of Chap. 2. Chapter 2 presents detailed discussions and evaluations pertinent to pumps, chemical regeneration, and other elements in the overall laser system. Chapter 3 briefly discusses those areas that require further work and the nature of the work required to complete the full-scale evaluation of the applicability of the iodine photodissociation laser to the inertial confinement program

  10. Strong field laser physics

    CERN Document Server

    2008-01-01

    Since the invention of the laser in the 1960s, people have strived to reach higher intensities and shorter pulse durations. High intensities and ultrashort pulse durations are intimately related. Recent developments have shown that high intensity lasers also open the way to realize pulses with the shortest durations to date, giving birth to the field of attosecond science (1 asec = 10-18s). This book is about high-intensity lasers and their applications. The goal is to give an up to date introduction to the technology behind these laser systems and to the broad range of intense laser applications. These applications include AMO (atomic molecular and optical) physics, x-ray science, attosecond science, plasma physics and particle acceleration, condensed matter science and laser micromachining, and finally even high-energy physics.

  11. Arduino based laser control

    OpenAIRE

    Bernal Muñoz, Ferran

    2015-01-01

    ARDUINO is a vey usefull platform for prototypes. In this project ARDUINO will be used for controling a Semiconductor Tuneable Laser. [ANGLÈS] Diode laser for communications control based on an Arduino board. Temperature control implementation. Software and hardware protection for the laser implementation. [CASTELLÀ] Control de un láser de comunicaciones ópticas desde el ordenador utilizando una placa Arduino. Implementación de un control de temperatura y protección software y hardware ...

  12. Shiva laser system performance

    International Nuclear Information System (INIS)

    Glaze, J.; Godwin, R.O.; Holzrichter, J.F.

    1978-01-01

    On November 18, 1977, after four years of experimentation, innovation, and construction, the Shiva High Energy Laser facility produced 10.2 kJ of focusable laser energy delivered in a 0.95 ns pulse. The Shiva laser, with its computer control system and delta amplifiers, demonstrated its versatility on May 18, 1978, when the first 20-beam target shot with delta amplifiers focused 26 TW on a target and produced a yield of 7.5 x 10 9 neutrons

  13. Lasers in Ophthalmology

    Institute of Scientific and Technical Information of China (English)

    1992-01-01

    In recent years,lasers have entered every fieldof medicine and especially so in ophthalmol-ogy.The scientific basis of lasers in ophthal-mology is based on three mechanisms:1.Photothermal effectLasers:argon,krypton,dye and diodeA thermal effect is generated when laserenergy is absorbed by pigment leading to in-creased vibration and therefore heat content.A

  14. Laser Journal (Selected Articles),

    Science.gov (United States)

    1982-09-10

    laser is described. The apparatus structure and some experimental results are reported. MATERIAL AND ELEMENT MAGNETO -OPTIC PROPERTIES OF Pr dYb),(1oAI...with a magneto -optical modulator. The measuring system is simple and sensitive, with reading accuracy of ±0.0050 and error 45%. STUDY ON EXPERIMENTAL...laser radiation therapy . He Fang de East Chiia Hospital APPLICATION OF N4d,:Y q LASER TO TREAT INTERNAL HEMERRHOID Zhuo Ruilin Zu Songlin (Shanghai

  15. Laser precision microfabrication

    CERN Document Server

    Sugioka, Koji; Pique, Alberto

    2010-01-01

    Miniaturization and high precision are rapidly becoming a requirement for many industrial processes and products. As a result, there is greater interest in the use of laser microfabrication technology to achieve these goals. This book composed of 16 chapters covers all the topics of laser precision processing from fundamental aspects to industrial applications to both inorganic and biological materials. It reviews the sate of the art of research and technological development in the area of laser processing.

  16. Lasers for the SILVA laser isotope separation process

    International Nuclear Information System (INIS)

    Lapierre, Y.

    1997-01-01

    The main principles of the laser isotope separation process for the production of enriched uranium at lower cost, are reviewed and the corresponding optimal laser characteristics are described. The development of the SILVA laser isotope separation process involved researches in the various domains of pump lasers, dye lasers, laser and optics systems and two test facilities for the feasibility studies which are expected for 1997

  17. High power lasers

    CERN Document Server

    Niku-Lari, A

    1989-01-01

    The use of lasers for the working and treatment of materials is becoming increasingly common in industry. However, certain laser applications, for example, in welding, cutting and drilling, are more widely exploited than others. Whilst the potential of lasers for the surface treatment of metals is well recognised, in practice, this particular application is a relative newcomer. The 24 papers in this volume present the latest research and engineering developments in the use of lasers for processes such as surface melting, surface alloying and cladding, and machining, as well as discussing th

  18. Degenerate band edge laser

    Science.gov (United States)

    Veysi, Mehdi; Othman, Mohamed A. K.; Figotin, Alexander; Capolino, Filippo

    2018-05-01

    We propose a class of lasers based on a fourth-order exceptional point of degeneracy (EPD) referred to as the degenerate band edge (DBE). EPDs have been found in parity-time-symmetric photonic structures that require loss and/or gain; here we show that the DBE is a different kind of EPD since it occurs in periodic structures that are lossless and gainless. Because of this property, a small level of gain is sufficient to induce single-frequency lasing based on a synchronous operation of four degenerate Floquet-Bloch eigenwaves. This lasing scheme constitutes a light-matter interaction mechanism that leads also to a unique scaling law of the laser threshold with the inverse of the fifth power of the laser-cavity length. The DBE laser has the lowest lasing threshold in comparison to a regular band edge laser and to a conventional laser in cavities with the same loaded quality (Q ) factor and length. In particular, even without mirror reflectors the DBE laser exhibits a lasing threshold which is an order of magnitude lower than that of a uniform cavity laser of the same length and with very high mirror reflectivity. Importantly, this novel DBE lasing regime enforces mode selectivity and coherent single-frequency operation even for pumping rates well beyond the lasing threshold, in contrast to the multifrequency nature of conventional uniform cavity lasers.

  19. Gigashot Optical Laser Demonstrator

    Energy Technology Data Exchange (ETDEWEB)

    Deri, R. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-10-13

    The Gigashot Optical Laser Demonstrator (GOLD) project has demonstrated a novel optical amplifier for high energy pulsed lasers operating at high repetition rates. The amplifier stores enough pump energy to support >10 J of laser output, and employs conduction cooling for thermal management to avoid the need for expensive and bulky high-pressure helium subsystems. A prototype amplifier was fabricated, pumped with diode light at 885 nm, and characterized. Experimental results show that the amplifier provides sufficient small-signal gain and sufficiently low wavefront and birefringence impairments to prove useful in laser systems, at repetition rates up to 60 Hz.

  20. Notes on Laser Acceleration

    International Nuclear Information System (INIS)

    Tajima, T.

    2008-01-01

    This note intends to motivate our effort toward the advent of new methods of particle acceleration, utilizing the fast rising laser technology. By illustrating the underlying principles in an intuitive manner and thus less jargon-clad fashion, we seek a direction in which we shall be able to properly control and harness the promise of laser acceleration. First we review the idea behind the laser wakefield. We then go on to examine ion acceleration by laser. We examine the sheath acceleration in particular and look for the future direction that allows orderly acceleration of ions in high energies

  1. X-ray lasers

    CERN Document Server

    Elton, Raymond C

    2012-01-01

    The first in its field, this book is both an introduction to x-ray lasers and a how-to guide for specialists. It provides new entrants and others interested in the field with a comprehensive overview and describes useful examples of analysis and experiments as background and guidance for researchers undertaking new laser designs. In one succinct volume, X-Ray Lasers collects the knowledge and experience gained in two decades of x-ray laser development and conveys the exciting challenges and possibilities still to come._Add on for longer version of blurb_M>The reader is first introduced

  2. Lasers in materials processing

    International Nuclear Information System (INIS)

    Davis, J.I.; Rockower, E.B.

    1981-01-01

    A status report on the uranium Laser Isotope Separation (LIS) Program at the Lawrence Livermore National Laboratory is presented. Prior to this status report, process economic analysis is presented so as to understand how the unique properties of laser photons can be best utilized in the production of materials and components despite the high cost of laser energy. The characteristics of potential applications that are necessary for success are identified, and those factors that have up to now frustrated attempts to find commercially viable laser induced chemical and physical process for the production of new or existing materials are pointed out

  3. Mid-Infrared Lasers

    Data.gov (United States)

    National Aeronautics and Space Administration — Mid infrared solid state lasers for Differential Absorption Lidar (DIAL) systems required for understanding atmospheric chemistry are not available. This program...

  4. Laser fusion program overview

    International Nuclear Information System (INIS)

    Emmett, J.L.

    1977-01-01

    This program is structured to proceed through a series of well defined fusion milestones to proof of the scientific feasibility, of laser fusion with the Shiva Nova system. Concurrently, those key technical areas, such as advanced lasers, which are required to progress beyond proof of feasibility, are being studied. We have identified and quantified the opportunities and key technical issues in military applications, such as weapons effects simulations, and in civilian applications, such as central-station electric power production. We summarize the current status and future plans for the laser fusion program at LLL, emphasizing the civilian applications of laser fusion

  5. Physics of semiconductor lasers

    CERN Document Server

    Mroziewicz, B; Nakwaski, W

    2013-01-01

    Written for readers who have some background in solid state physics but do not necessarily possess any knowledge of semiconductor lasers, this book provides a comprehensive and concise account of fundamental semiconductor laser physics, technology and properties. The principles of operation of these lasers are therefore discussed in detail with the interrelations between their design and optical, electrical and thermal properties. The relative merits of a large number of laser structures and their parameters are described to acquaint the reader with the various aspects of the semiconductor l

  6. Principles of laser dynamics

    CERN Document Server

    Khanin, YI

    1995-01-01

    This monograph summarizes major achievements in laser dynamics over the past three decades. The book begins with two introductory Chapters. Chapter 1 offers general considerations on quantum oscillators, formulates the requirements for the laser key elements and shows how these requirements are met in different laser systems. The second Chapter proposes the mathematical models used in semiclassical laser theory, discusses the approximations and simplifications in particular cases, and specifies the range of applicability of these models. In Chapters 3-5 attention is given primarily to the stea

  7. Laser transmitter system

    International Nuclear Information System (INIS)

    Dye, R.A.

    1975-01-01

    A laser transmitter system is disclosed which utilizes mechanical energy for generating an output pulse. The laser system includes a current developing device such as a piezoelectric crystal which charges a storage device such as a capacitor in response to a mechanical input signal. The capacitor is coupled to a switching device, such as a silicon controlled rectifier (SCR). The switching device is coupled to a laser transmitter such as a GaAs laser diode, which provides an output signal in response to the capacitor being discharged

  8. Laser in urology

    International Nuclear Information System (INIS)

    Breisland, H.O.

    1991-01-01

    The neodymium YAG laser is particularly suited for endoscopic urologic surgery because the YAG laser light can be conducted in flexible fibers. Superficial bladder tumours can be treated under local anaesthesia in the outpatient department. The frequency of local recurrences is low, significantly lower than after electrosection or electrocoagulation. Selected cases of T2-muscle invasive bladder tumours can be cured with laser coagulation applied subsequently to transurethral resection. Combined treatment with electrosection and laser coagulation of localized prostatic cancer is a promising method which compares favourably with results obtained by other treatment modalities. Tumours in the upper urinary tract can be laser-treated through ureteroscopes or nephroscopes, but the treatment should be limited to low stage, low grade tumours. Laser is the treatment of choice for intraurethral condylomatas. Laser treatment of penil carcinoma gives excellent cosmetic and functional results and few local recurrences. Laser lithotripsy is a new technique for treatment of ureteric stones and photodynamic laser therapy is a promising tecnique for treatment of carcinoma in situ in the bladder empithelium. However, neither of these techniques are available for clinical use in Norway as yet. 17 refs., 3 figs., 1 tabs

  9. Tunable Microfluidic Dye Laser

    DEFF Research Database (Denmark)

    Olsen, Brian Bilenberg; Helbo, Bjarne; Kutter, Jörg Peter

    2003-01-01

    We present a tunable microfluidic dye laser fabricated in SU-8. The tunability is enabled by integrating a microfluidic diffusion mixer with an existing microfluidic dye laser design by Helbo et al. By controlling the relative flows in the mixer between a dye solution and a solvent......, the concentration of dye in the laser cavity can be adjusted, allowing the wavelength to be tuned. Wavelength tuning controlled by the dye concentration was demonstrated with macroscopic dye lasers already in 1971, but this principle only becomes practically applicable by the use of microfluidic mixing...

  10. Trends in laser micromachining

    Science.gov (United States)

    Gaebler, Frank; van Nunen, Joris; Held, Andrew

    2016-03-01

    Laser Micromachining is well established in industry. Depending on the application lasers with pulse length from μseconds to femtoseconds and wavelengths from 1064nm and its harmonics up to 5μm or 10.6μm are used. Ultrafast laser machining using pulses with pico or femtosecond duration pulses is gaining traction, as it offers very precise processing of materials with low thermal impact. Large-scale industrial ultrafast laser applications show that the market can be divided into various sub segments. One set of applications demand low power around 10W, compact footprint and are extremely sensitive to the laser price whilst still demanding 10ps or shorter laser pulses. A second set of applications are very power hungry and only become economically feasible for large scale deployments at power levels in the 100+W class. There is also a growing demand for applications requiring fs-laser pulses. In our presentation we would like to describe these sub segments by using selected applications from the automotive and electronics industry e.g. drilling of gas/diesel injection nozzles, dicing of LED substrates. We close the presentation with an outlook to micromachining applications e.g. glass cutting and foil processing with unique new CO lasers emitting 5μm laser wavelength.

  11. Scanning Color Laser Microscope

    Science.gov (United States)

    Awamura, D.; Ode, T.; Yonezawa, M.

    1988-01-01

    A confocal color laser microscope which utilizes a three color laser light source (Red: He-Ne, Green: Ar, Blue: Ar) has been developed and is finding useful applications in the semiconductor field. The color laser microscope, when compared to a conventional microscope, offers superior color separation, higher resolution, and sharper contrast. Recently some new functions including a Focus Scan Memory, a Surface Profile Measurement System, a Critical Dimension Measurement system (CD) and an Optical Beam Induced Current Function (OBIC) have been developed for the color laser microscope. This paper will discuss these new features.

  12. High Power Vanadate lasers

    CSIR Research Space (South Africa)

    Strauss

    2006-07-01

    Full Text Available stream_source_info Strauss1_2006.pdf.txt stream_content_type text/plain stream_size 3151 Content-Encoding UTF-8 stream_name Strauss1_2006.pdf.txt Content-Type text/plain; charset=UTF-8 Laser Research Institute... University of Stellenbosch www.laser-research.co.za High Power Vanadate lasers H.J.Strauss, Dr. C. Bollig, R.C. Botha, Prof. H.M. von Bergmann, Dr. J.P. Burger Aims 1) To develop new techniques to mount laser crystals, 2) compare the lasing properties...

  13. Laser adaptive holographic hydrophone

    Energy Technology Data Exchange (ETDEWEB)

    Romashko, R V; Kulchin, Yu N; Bezruk, M N; Ermolaev, S A [Institute of Automation and Control Processes, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok (Russian Federation)

    2016-03-31

    A new type of a laser hydrophone based on dynamic holograms, formed in a photorefractive crystal, is proposed and studied. It is shown that the use of dynamic holograms makes it unnecessary to use complex optical schemes and systems for electronic stabilisation of the interferometer operating point. This essentially simplifies the scheme of the laser hydrophone preserving its high sensitivity, which offers the possibility to use it under a strong variation of the environment parameters. The laser adaptive holographic hydrophone implemented at present possesses the sensitivity at a level of 3.3 mV Pa{sup -1} in the frequency range from 1 to 30 kHz. (laser hydrophones)

  14. Introduction to laser technology

    CERN Document Server

    Hitz, C Breck; Hecht, Jeff

    2012-01-01

    The only introductory text on the market today that explains the underlying physics and engineering applicable to all lasersAlthough lasers are becoming increasingly important in our high-tech environment, many of the technicians and engineers who install, operate, and maintain them have had little, if any, formal training in the field of electro-optics. This can result in less efficient usage of these important tools. Introduction to Laser Technology, Fourth Edition provides readers with a good understanding of what a laser is and what it can and cannot do. The book explains what types of las.

  15. Laser-induced interactions

    International Nuclear Information System (INIS)

    Green, W.R.

    1979-01-01

    This dissertation discusses some of the new ways that lasers can be used to control the energy flow in a medium. Experimental and theoretical considerations of the laser-induced collision are discussed. The laser-induced collision is a process in which a laser is used to selectively transfer energy from a state in one atomic or molecular species to another state in a different species. The first experimental demonstration of this process is described, along with later experiments in which lasers were used to create collisional cross sections as large as 10 - 13 cm 2 . Laser-induced collisions utilizing both a dipole-dipole interaction and dipole-quadrupole interaction have been experimentally demonstrated. The theoretical aspects of other related processes such as laser-induced spin-exchange, collision induced Raman emission, and laser-induced charge transfer are discussed. Experimental systems that could be used to demonstrate these various processes are presented. An experiment which produced an inversion of the resonance line of an ion by optical pumping of the neutral atom is described. This type of scheme has been proposed as a possible method for constructing VUV and x-ray lasers

  16. Jet laser ion source

    International Nuclear Information System (INIS)

    Dem'yanov, A.V.; Sidorov, S.V.

    1994-01-01

    External laser injector of multicharged ions (MCI) is developed in which wide-aperture aberration-free wire gauze spherical shape electrodes are applied for effective MCI extraction from laser plasma and beam focusing. Axial plasma compression by solenoid magnetic field is used to reduce ion losses due to transverse movement of the scattering laser plasma. Transverse magnetic field created by another solenoid facilitates the effective laser plasma braking and consequently, leads to the narrowing of energy spectrum of plasma ions and its shift towards lower energies. 2 refs.; 3 figs

  17. Free electron laser

    International Nuclear Information System (INIS)

    Ortega, J.M.; Billardon, M.

    1986-01-01

    Operation principle of a laser and an oscillator are recalled together with the klystron one. In the free electron laser, electrons go through an undulator or an optical klystron. Principles of the last one are given. The two distinct ways of producing coherent radiation with an undulator and an optical klystron are presented. The first one is the use of the free electron laser, the second is to make use of the spontaneous emission generation (harmonics generation). The different current types of free electron lasers are presented (Stanford, Los Alamos, Aco at Orsay). Prospects and applications are given in conclusion [fr

  18. Laser cooling of solids

    CERN Document Server

    Petrushkin, S V

    2009-01-01

    Laser cooling is an important emerging technology in such areas as the cooling of semiconductors. The book examines and suggests solutions for a range of problems in the development of miniature solid-state laser refrigerators, self-cooling solid-state lasers and optical echo-processors. It begins by looking at the basic theory of laser cooling before considering such topics as self-cooling of active elements of solid-state lasers, laser cooling of solid-state information media of optical echo-processors, and problems of cooling solid-state quantum processors. Laser Cooling of Solids is an important contribution to the development of compact laser-powered cryogenic refrigerators, both for the academic community and those in the microelectronics and other industries. Provides a timely review of this promising field of research and discusses the fundamentals and theory of laser cooling Particular attention is given to the physics of cooling processes and the mathematical description of these processes Reviews p...

  19. Laser beam diagnostics for kilowatt power pulsed YAG laser

    International Nuclear Information System (INIS)

    Liu, Yi; Leong, Keng H.

    1992-01-01

    There is a growing need for high power YAG laser beam diagnostics with the recent introduction of such lasers in laser material processing. In this paper, we will describe the use of a commercially available laser beam analyzer (Prometec) to profile the laser beam from a 1600 W pulsed Nd:YAG laser that has a 1 mm fiber optic beam delivery system. The selection of laser pulse frequency and pulse width for the measurement is discussed. Laser beam propagation parameters by various optical components such as fibers and lenses can be determined from measurements using this device. The importance of such measurements will be discussed

  20. Laser Program annual report 1987

    Energy Technology Data Exchange (ETDEWEB)

    O' Neal, E.M.; Murphy, P.W.; Canada, J.A.; Kirvel, R.D.; Peck, T.; Price, M.E.; Prono, J.K.; Reid, S.G.; Wallerstein, L.; Wright, T.W. (eds.)

    1989-07-01

    This report discusses the following topics: target design and experiments; target materials development; laboratory x-ray lasers; laser science and technology; high-average-power solid state lasers; and ICF applications studies.

  1. Laser Program annual report 1987

    International Nuclear Information System (INIS)

    O'Neal, E.M.; Murphy, P.W.; Canada, J.A.; Kirvel, R.D.; Peck, T.; Price, M.E.; Prono, J.K.; Reid, S.G.; Wallerstein, L.; Wright, T.W.

    1989-07-01

    This report discusses the following topics: target design and experiments; target materials development; laboratory x-ray lasers; laser science and technology; high-average-power solid state lasers; and ICF applications studies

  2. Temperature controller of semiconductor laser

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Vít; Číp, Ondřej

    2003-01-01

    Roč. 73, č. 3 (2003), s. 10 - 12 ISSN 0928-5008 Institutional research plan: CEZ:AV0Z2065902 Keywords : temperature controller * semiconductor laser * laser diode Subject RIV: BH - Optics, Masers, Lasers

  3. LASERS: A cryogenic slab CO laser

    Science.gov (United States)

    Ionin, Andrei A.; Kozlov, A. Yu; Seleznev, L. V.; Sinitsyn, D. V.

    2009-03-01

    A compact capacitive transverse RF-discharge-pumped slab CO laser with cryogenically cooled electrodes, which operates both in the cw and repetitively pulsed regimes, is fabricated. The laser operation is studied in the free running multifrequency regime at the vibrational - rotational transitions of the fundamental (V + 1 → V) vibrational bands of the CO molecule in the spectral region from 5.1 to 5.4 μm. Optimal operation conditions (gas mixture composition and pressure, RF pump parameters) are determined. It is shown that only gas mixtures with a high content of oxygen (up to 20% with respect to the concentration of CO molecules) can be used as an active medium of this laser. It is demonstrated that repetitively pulsed pumping is more efficient compared to cw pumping. In this case, quasi-cw lasing regime can be obtained. The maximum average output power of ~12 W was obtained for this laser operating on fundamental bands and its efficiency achieved ~14 %. The frequency-selective operation regime of the slab RF-discharge-pumped CO laser was realised at ~ 100 laser lines in the spectral region from 5.0 to 6.5 μm with the average output power of up to several tens of milliwatts in each line. Lasing at the transitions of the first vibrational overtone (V + 2 → V) of the CO molecule is obtained in the spectral region from 2.5 to 3.9 μm. The average output power of the overtone laser achieved 0.3 W. All the results were obtained without the forced gas mixture exchange in the discharge chamber. Under fixed experimental conditions, repetitively pulsed lasing (with fluctuations of the output characteristics no more than ±10 %) was stable for more than an hour.

  4. Power balancing of multibeam laser fusion lasers

    International Nuclear Information System (INIS)

    Seka, W.; Morse, S.; Letzring, S.; Kremens, R.; Kessler, T.J.; Jaanimagi, P.; Keck, R.; Verdon, C.; Brown, D.

    1989-01-01

    The success of laser fusion depends to a good degree on the ability to compress the target to very high densities of ≥1000 times liquid DT. To achieve such compressions require that the irradiation nonuniformity must not exceed ∼1% rms over the whole time of the compression, particularly during the early phases of irradiation. The stringent requirements for the irradiation uniformity for laser fusion have been known for quite some time but until recently the energy balance was mistakenly equated to power balance. The authors describe their effort on energy balance and irradiation patterns on the target. They significantly improved the laser performance with respect to overall intensity distributions on target including the implementation of distributed (random) phase plates in each high power beam. However, the slightly varying performance of the third harmonic conversion crystals in the twenty-four beams of their laser system was generally compensated for by appropriately adjusted 1.054μm input laser energy. Computational analysis of the results of the recent high density campaign are shown

  5. Laser Stabilization with Laser Cooled Strontium

    DEFF Research Database (Denmark)

    Christensen, Bjarke Takashi Røjle

    The frequency stability of current state-of-the-art stabilized clock lasers are limited by thermal fluctuations of the ultra-stable optical reference cavities used for their frequency stabilization. In this work, we study the possibilities for surpassing this thermal limit by exploiting the nonli......The frequency stability of current state-of-the-art stabilized clock lasers are limited by thermal fluctuations of the ultra-stable optical reference cavities used for their frequency stabilization. In this work, we study the possibilities for surpassing this thermal limit by exploiting...... the nonlinear effects from coupling of an optical cavity to laser cooled atoms having a narrow transition linewidth. Here, we have realized such a system where a thermal sample of laser cooled strontium-88 atoms are coupled to an optical cavity. The strontium-88 atoms were probed on the narrow 1S0-3P1 inter......-combination line at 689 nm in a strongly saturated regime. The dynamics of the atomic induced phase shift and absorption of the probe light were experimentally studied in details with the purpose of applications to laser stabilization. The atomic sample temperature was in the mK range which brought this system out...

  6. High-power pulsed lasers

    International Nuclear Information System (INIS)

    Holzrichter, J.F.

    1980-01-01

    The ideas that led to the successful construction and operation of large multibeam fusion lasers at the Lawrence Livermore Laboratory are reviewed. These lasers are based on the use of Nd:glass laser materials. However, most of the concepts are applicable to any laser being designed for fusion experimentation. This report is a summary of lectures given by the author at the 20th Scottish University Summer School in Physics, on Laser Plasma Interaction. This report includes basic concepts of the laser plasma system, a discussion of lasers that are useful for short-pulse, high-power operation, laser design constraints, optical diagnostics, and system organization

  7. Laser safety tools and training

    CERN Document Server

    Barat, Ken

    2008-01-01

    Lasers perform many unique functions in a plethora of applications, but there are many inherent risks with this continually burgeoning technology. Laser Safety: Tools and Training presents simple, effective ways for users in a variety of facilities to evaluate the hazards of any laser procedure and ensure they are following documented laser safety standards.Designed for use as either a stand-alone volume or a supplement to Laser Safety Management, this text includes fundamental laser and laser safety information and critical laser use information rarely found in a single source. The first lase

  8. As possibilidades de enfrentamento da violência infantil na consulta de enfermagem sistematizada Posibilidades de enfrentamiento de la violencia infantil en la consulta de enfermería sistematizada Possibilities for addressing child abuse in systematized nursing consultations

    Directory of Open Access Journals (Sweden)

    Maíra Rosa Apostólico

    2013-04-01

    Full Text Available A violência infantil vem crescendo e aos serviços de saúde compete lidar com este fenômeno. A CIPESC® é uma ferramenta sistematizadora do cuidado e pode visibilizar a violência infantil nas consultas de enfermagem. Este estudo buscou identificar os limites e potencialidades da CIPESC® na consulta de enfermagem com crianças vítimas de violência doméstica. Estudo descritivo, qualitativo, tipo estudo de caso, analisou 15 relatos por web-questionário de enfermeiros da atenção básica, da Secretaria Municipal de Curitiba, Paraná, sobre a ocorrência de violência. Embora a CIPESC® tenha mostrado potencialidades, os diagnósticos e intervenções existentes da nomenclatura não foram plenamente acionados pelos pesquisados. Apresentou limites preocupantes no que tange ao reconhecimento das necessidades e vulnerabilidades que envolvem o fenômeno da violência. Conclui-se que é preciso agregar à nomenclatura os atributos referentes à liberdade e autonomia, essenciais para o enfrentamento da violência, além de maneiras de intervir baseadas em evidências.La violencia infantil está en crecimiento, compete a los servicios de salud enfrentar el fenómeno. La CIPESC®, herramienta de sistematización del cuidado, puede visibilizar la violencia infantil en las consultas de enfermería. Se buscó identificar límites y posibilidades de la CIPESC® en consulta de enfermería con niños víctimas de violencia doméstica. Estudio descriptivo, cualitativo, tipo estudio de caso; analizando 15 testimonios por cuestionario-web de enfermeros de atención primaria de la Secretaría Municipal de Curitiba-PA, sobre ocurrencia de violencia. Aunque la CIPESC® haya expresado potencialidades, los diagnósticos e intervenciones existentes en la nomenclatura no fueron plenamente accionados por los entrevistados. Presentó límites preocupantes en lo atinente al reconocimiento de necesidades y vulnerabilidades que envuelven al fenómeno de la violencia

  9. DANÇA ALÉM DA VISÃO: POSSIBILIDADES DO CORPO CEGO DANCE BEYOND THE VISION: POSSIBILITIES OF THE BLIND BODY DANZA MÁS ALLÁ DE LA VISIÓN: POSIBILIDADES DEL CUERPO CIEGO

    Directory of Open Access Journals (Sweden)

    2008-12-01

    Full Text Available

    O artigo suscita reflexões sobre as possibilidades do corpo cego e a interação com a dança na construção da autonomia. Autores como Fleming, Frazão e Lusseyran apontam questões sobre a rede tecida pelos sentidos na formação de imagens sensório-motoras pelo deficiente visual. Damásio contribui para o entendimento de emoção e razão; Llinás explica a construção do movimento baseado na Neurociência; Katz traz a Teoria do Corpomídia para pensar a dança como cognição. As considerações finais observam a dança como parte do conhecimento humano sendo um espaço que possibilita o entrelaçamento de saberes, visto que o ser humano se constrói em rede pelo imbricamento entre corpo, ambiente e cultura.

    The article raises thoughts on the possibilities of the blind body and the interaction with the dance in the construction of autonomy. Authors such as Fleming, Frazão and Lusseyran point to questions about the network woven by the senses in the formation of sensory-motor images by the visual disabled. Damásio contributes to the understanding of emotion and reason; Llinás explains the construction of the movement based in Neurosciences; Katz brings the Corpomídia theory to think dance as cognition. The final considerations observe dance as part of the human knowledge being an space that allows the connection of knowledge, because the human being is built into the network between body, environment and culture.

    El artículo suscita reflexiones sobre las posibilidades del cuerpo ciego y la interacción con la danza en la construcción de la autonomía. Autores como Fleming, Frazao y Lusseyran apuntan cuestiones sobre la red tejida por los sentidos en la formación de imágenes sensorial-motrices por el discapacitado visual. Damásio contribuyó para el entendimiento de emoción y

  10. Meta-avaliação: das abordagens às possibilidades de aplicação Metaevaluación: de los abordajes a las posibilidades de aplicación Metaevaluation: from approaches to possibilities of application

    Directory of Open Access Journals (Sweden)

    Ligia Gomes Elliot

    2011-12-01

    Full Text Available Dada a importância de seus resultados, projetos, programas e serviços dirigidos a diferentes segmentos da sociedade têm sido acompanhados por avaliações que buscam revelar se houve o alcance da desejada qualidade. No entanto, a condução adequada dessas avaliações pode ser posta em cheque, isto é, verificada por meio de meta-avaliações. Meta-avaliação foi definida como a avaliação de uma avaliação. Assim, o presente artigo apresenta algumas abordagens que representam a contribuição de diversos autores para a realização de meta-avaliações. São abordagens aplicáveis a meta-avaliações somativas e formativas. Algumas indicações de meta-avaliações já desenvolvidas fazem parte do artigo, que destaca as possibilidades de utilização da última versão publicada dos padrões internacionais de avaliação, do Joint Committee on Standards for Educational Evaluation.Dada la importancia de sus resultados, proyectos, programas y servicios dirigidos a diferentes segmentos de la sociedad han debido estar acompañados por evaluaciones que tratan de revelar si se alcanzó la calidad deseada. Aunque las metaevaluaciones han tenido una correcta conducción, ésta puede ser puesta en jaque, es decir, se puede verificar por medio de metaevaluaciones. Es bueno recordar que se definió la metaevaluación como la evaluación de una evaluación. Este artículo presenta algunos abordajes que representan la contribución de diversos autores para la realización de metaevaluaciones. Dichos abordajes se aplican a metaevaluaciones sumativas y formativas. Algunas indicaciones de las metaevaluaciones ya desarrolladas integran este artículo, que pone de relieve las posibilidades de utilización de la última versión publicada de los modelos internacionales de evaluación, del Joint Committee on Standards for Educational Evaluations.Given the importance of their results, projects, programs and services aimed at different segments of society

  11. El movimiento de la existencia: posibilidades y límites de la descripción fenomenológica de la corporeidad The movement of existence: possibilities and limits of the phenomenological description of embodiment

    Directory of Open Access Journals (Sweden)

    César Augusto Delgado Lombana

    2010-06-01

    Full Text Available En el presente texto, se pretende evidenciar los alcances de la propuesta de una fenomenología de la percepción desde Maurice Merleau Ponty. En el artículo se desarrollan dos argumentos: el objetivo de Merleau-Ponty quien se opone a las teorías psicologistas que han reducido la percepción a la sensación pura, es decir, a la aprehensión de datos sensitivos aislados. Por el contrario, deseamos evidenciar que Merleau-Ponty comprende la percepción como la interpretación de un horizonte de significación (perspectiva que permite la correlación entre sujeto y objeto. En sentido estricto, percibir es la posibilidad de comprender que el objeto se da en ámbitos de significación que permiten la constitución entre sujeto y objeto. Esta tesis tendrá por consecuencia más próxima que la escisión sujeto objeto se supere y se vea la doble faz de la percepción: la perspectiva (estructura objeto-horizonte, la cual me permite experienciar objetos no como meros datos aislados, sino como horizonte, es decir, como ámbitos de significación. En segundo lugar, será necesario abordar las críticas de Merleau-Ponty a las teorías sobre el cuerpo que, en su aspecto más radical, han conducido a la cosificación del mismo, es decir, a la reducción de la corporalidad a una cosa más entre las cosasThis paper presents phenomenology from the point of view of Maurice Merleau Ponty. Two arguments are developed: Merleau-Ponty's aim is opposed to the psychologist theories that reduce perception to pure sensation, that is to say, to the apprehension of isolated sensual information. In contrast, we want to demonstrate that Merleau-Ponty understands perception as the interpretation of an horizon of meanings and perspectives that leads to correlations between subject and object. In strict sense, to perceive is to understand that the object shows itself in areas of meaning that leads to its constitution between subject and object. This thesis will have as

  12. Laser biostimulation in pediatrics

    Science.gov (United States)

    Utz, Irina A.; Lagutina, L. E.; Tuchin, Valery V.

    1995-01-01

    In the present paper the method and apparatus for percutaneous laser irradiation of blood (PLIB) in vessels (veins) are described. Results of clinical investigations of biostimulating effects under PLIB by red laser light (633 nm) in Cubiti and Saphena Magna veins are presented.

  13. Metallic DFB lasers

    NARCIS (Netherlands)

    Marell, M.J.H.; Nötzel, R.; Smit, M.K.; Hill, M.T.; Pozo, J.; Mortensen, M.; Urbach, P.; Leijtens, X.; Yousefi, M.

    2010-01-01

    In this paper we present our latest results on the design, fabrication and characterization of metal coated DFB lasers. These devices are based on a specialform of the metal-insulator-metal waveguides, which support plasmon gap modes. The distributed feedback provides control over the laser ~

  14. Laser processing of materials

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    The initial foundation of laser theory was laid by Einstein [11]. ..... general definition and scope of the processes as understood in conventional practice, but is ..... [54]. Laser welding of Ti-alloys. Welding. 2001 TiNi shape memory alloys. CW–CO2. Study corrosion, mechanical and shape memory properties of weldments.

  15. Microfluidic Dye Lasers

    DEFF Research Database (Denmark)

    Kristensen, Anders; Balslev, Søren; Gersborg-Hansen, Morten

    2006-01-01

    A technology for miniaturized, polymer based lasers, suitable for integration with planar waveguides and microfluidic networks is presented. The microfluidic dye laser device consists of a microfluidic channel with an embedded optical resonator. The devices are fabricated in a thin polymer film...

  16. Laser trabeculotomy versus trabeculoplasty

    International Nuclear Information System (INIS)

    Ticho, U.; Frucht, J.

    1984-01-01

    Although laser trabeculotomy has failed in glaucoma management, the laser trabeculoplasty (LTP) procedure has proved to be helpful. LTP was found to improve glaucoma control in 80-90% of open angle glaucoma patients, and less in secondary glaucoma and low tension glaucoma (50%). The procedure is more successful in dark iris eyes and complications are transient. (Auth.)

  17. 5. Laser plasma interaction

    International Nuclear Information System (INIS)

    Labaune, C.; Fuchs, J.; Bandulet, H.

    2002-01-01

    Imprint elimination, smoothing and preheat control are considerable problems in inertial fusion and their possible solution can be achieved by using low-density porous materials as a buffer in target design. The articles gathered in this document present various aspects of the laser-plasma interaction, among which we have noticed: -) numerical algorithmic improvements of the Vlasov solver toward the simulation of the laser-plasma interaction are proposed, -) the dependence of radiation temperatures and X-ray conversion efficiencies of hohlraum on the target structures and laser irradiation conditions are investigated, -) a study of laser interaction with ultra low-density (0,5 - 20 mg/cm 3 ) porous media analyzing backscattered light at incident laser frequency ω 0 and its harmonics 3*ω 0 /2 and 2*ω 0 is presented, -) investigations of laser interaction with solid targets and crater formation are carried out with the objective to determine the ablation loading efficiency, -) a self organization in an intense laser-driven plasma and the measure of the relative degree of order of the states in an open system based on the S-theorem are investigated, and -) the existence and stability of electromagnetic solitons generated in a relativistic interaction of an intense laser light with uniform under-dense cold plasma are studied

  18. Laser Interference Lithography

    NARCIS (Netherlands)

    van Wolferen, Hendricus A.G.M.; Abelmann, Leon; Hennessy, Theodore C.

    In this chapter we explain how submicron gratings can be prepared by Laser Interference Lithography (LIL). In this maskless lithography technique, the standing wave pattern that exists at the intersection of two coherent laser beams is used to expose a photosensitive layer. We show how to build the

  19. Levitated droplet dye laser

    DEFF Research Database (Denmark)

    Azzouz, H.; Alkafadiji, L.; Balslev, Søren

    2006-01-01

    a high quality optical resonator. Our 750 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. The droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating...

  20. Laser induced energy transfer

    International Nuclear Information System (INIS)

    Falcone, R.W.

    1979-01-01

    Two related methods of rapidly transferring stored energy from one excited chemical species to another are described. The first of these, called a laser induced collision, involves a reaction in which the energy balance is met by photons from an intense laser beam. A collision cross section of ca 10 - 17 cm 2 was induced in an experiment which demonstrated the predicted dependence of the cross section on wavelength and power density of the applied laser. A second type of laser induced energy transfer involves the inelastic scattering of laser radiation from energetically excited atoms, and subsequent absorption of the scattered light by a second species. The technique of producing the light, ''anti-Stokes Raman'' scattering of visible and infrared wavelength laser photons, is shown to be an efficient source of narrow bandwidth, high brightness, tunable radiation at vacuum ultraviolet wavelengths by using it to excite a rare gas transition at 583.7 A. In addition, this light source was used to make the first measurement of the isotopic shift of the helium metastable level at 601 A. Applications in laser controlled chemistry and spectroscopy, and proposals for new types of lasers using these two energy transfer methods are discussed

  1. Coaxial short pulsed laser

    Science.gov (United States)

    Nelson, M.A.; Davies, T.J.

    1975-08-01

    This invention relates to a laser system of rugged design suitable for use in a field environment. The laser itself is of coaxial design with a solid potting material filling the space between components. A reservoir is employed to provide a gas lasing medium between an electrode pair, each of which is connected to one of the coaxial conductors. (auth)

  2. LASER EN LARYNGOLOGIE

    African Journals Online (AJOL)

    9 mai 2013 ... permettant selon les besoins, coagulation, section ou vaporisation. ... tés par laser au service d'ORL et de chirurgie cervico-. LASER EN .... nose était de siège glottique pur à type de palmure dans. 3 cas et supra glottique ...

  3. Lasers in nuclear physics

    International Nuclear Information System (INIS)

    Inamura, T.T.

    1988-01-01

    The hyperfine interaction has been reviewed from a point of view of nuclear physics. Recent progress of nuclear spectroscopy with lasers is presented as one of laser studies of fundamental physics currently pursued in Japan. Especially, the hyperfine anomaly is discussed in connection with the origin of nuclear magnetism. (author)

  4. for aqueous dye lasers

    Indian Academy of Sciences (India)

    2014-02-12

    Feb 12, 2014 ... inclusion complex of RhB with the container molecule cucurbit[7]uril (CB[7]). Keywords. Temperature-dependent fluorescence; Rhodamine B; cucurbit[7]uril; host–guest complex; dye laser. PACS Nos 36.20.kd; 83.60.pq; 87.64.kv. 1. Introduction. Rhodamine B (RhB) is an efficient and photostable laser dye ...

  5. Electrodeless excimer laser

    International Nuclear Information System (INIS)

    Lisi, N.

    2001-01-01

    In this paper it is proposed how to build an excimer laser based on an electrodeless discharge (or Dielectric Barrier Discharge). Such laser could operate with a low energy per pulse ( 2 excimer molecule, whose emission wavelength in the VUV range (157 nm) at high reprate is particularly interesting in the micro-lithography field [it

  6. Auricular Acupuncture with Laser

    Science.gov (United States)

    Bahr, Frank

    2013-01-01

    Auricular acupuncture is a method which has been successfully used in various fields of medicine especially in the treatment of pain relief. The introduction of lasers especially low-level lasers into medicine brought besides the already existing stimulation with needles and electricity an additional technique to auricular acupuncture. This literature research looks at the historical background, the development and the anatomical and neurological aspects of auricular acupuncture in general and auricular laser acupuncture in detail. Preliminary scientific findings on auricular acupuncture with laser have been described in detail and discussed critically in this review article. The results of the studies have shown evidence of the effect of auricular laser acupuncture. However, a comparison of these studies was impossible due to their different study designs. The most important technical as well as study parameters were described in detail in order to give more sufficient evidence and to improve the quality of future studies. PMID:23935695

  7. Powering laser diode systems

    CERN Document Server

    Trestman, Grigoriy A

    2017-01-01

    This Tutorial Text discusses the competent design and skilled use of laser diode drivers (LDDs) and power supplies (PSs) for the electrical components of laser diode systems. It is intended to help power-electronic design engineers during the initial design stages: the choice of the best PS topology, the calculation of parameters and components of the PS circuit, and the computer simulation of the circuit. Readers who use laser diode systems for research, production, and other purposes will also benefit. The book will help readers avoid errors when creating laser systems from ready-made blocks, as well as understand the nature of the "mystical failures" of laser diodes (and possibly prevent them).

  8. Laser Beam Focus Analyser

    DEFF Research Database (Denmark)

    Nielsen, Peter Carøe; Hansen, Hans Nørgaard; Olsen, Flemming Ove

    2007-01-01

    the obtainable features in direct laser machining as well as heat affected zones in welding processes. This paper describes the development of a measuring unit capable of analysing beam shape and diameter of lasers to be used in manufacturing processes. The analyser is based on the principle of a rotating......The quantitative and qualitative description of laser beam characteristics is important for process implementation and optimisation. In particular, a need for quantitative characterisation of beam diameter was identified when using fibre lasers for micro manufacturing. Here the beam diameter limits...... mechanical wire being swept through the laser beam at varying Z-heights. The reflected signal is analysed and the resulting beam profile determined. The development comprised the design of a flexible fixture capable of providing both rotation and Z-axis movement, control software including data capture...

  9. Introducing the yellow laser

    Science.gov (United States)

    Lincoln, James

    2018-02-01

    The author has acquired a yellow laser with the specific wavelength of 589 nm. Because this is the first time such a laser has been discussed in this journal, I feel it is appropriate to provide a discussion of its function and capabilities. Normal laser safety should be employed, such as not pointing it into eyes or at people, and using eye protection for the young and inexperienced. It is important to note that 589 nm is the same wavelength as the Sodium-D line (doublet). This allows for the laser to serve as a replacement for sodium lamps, and, considering its rather high price, this added value should be balanced against its cost. What follows is a list of activities that showcase the yellow laser's unique promise as an engaging piece of technology that can be used in the teaching of physics.

  10. Regenerative similariton laser

    Directory of Open Access Journals (Sweden)

    Thibault North

    2016-05-01

    Full Text Available Self-pulsating lasers based on cascaded reshaping and reamplification (2R are capable of initiating ultrashort pulses despite the accumulation of large amounts of nonlinearities in all-fiber resonators. The spectral properties of pulses in self-similar propagation are compatible with cascaded 2R regeneration by offset filtering, making parabolic pulses suitable for the design of a laser of this recently introduced class. A new type of regenerative laser giving birth to similaritons is numerically investigated and shows that this laser is the analog of regenerative sources based solely on self-phase modulation and offset filtering. The regenerative similariton laser does not suffer from instabilities due to excessive nonlinearities and enables ultrashort pulse generation in a simple cavity configuration.

  11. Femtosecond Laser Filamentation

    CERN Document Server

    Chin, See Leang

    2010-01-01

    Femtosecond Laser Filamentation gives a comprehensive review of the physics of propagation of intense femtosecond laser pulses in optical media (principally air) and the applications and challenges of this new technique. This book presents the modern understanding of the physics of femtosecond laser pulse propagation, including unusual new effects such as the self-transformation of the pulse into a white light laser pulse, intensity clamping, the physics of multiple filamentation and competition, and how filaments’ ability to melt glass leads to wave guide writing. The potential applications of laser filamentation in atmospheric sensing and the generation of other electromagnetic pulses from the UV to the radio frequency are treated, together with possible future challenges in the excitation of super-excited states of molecules. Exciting new phenomena such as filament induced ultrafast birefringence and the excitation of molecular rotational wave packets and their multiple revivals in air (gases) will also ...

  12. NASA Space Laser Technology

    Science.gov (United States)

    Krainak, Michael A.

    2015-01-01

    Over the next two decades, the number of space based laser missions for mapping, spectroscopy, remote sensing and other scientific investigations will increase several fold. The demand for high wall-plug efficiency, low noise, narrow linewidth laser systems to meet different systems requirements that can reliably operate over the life of a mission will be high. The general trends will be for spatial quality very close to the diffraction limit, improved spectral performance, increased wall-plug efficiency and multi-beam processing. Improved spectral performance will include narrower spectral width (very near the transform limit), increased wavelength stability and or tuning (depending on application) and lasers reaching a wider range of wavelengths stretching into the mid-infrared and the near ultraviolet. We are actively developing high efficiency laser transmitter and high-sensitivity laser receiver systems that are suitable for spaceborne applications.

  13. Laser-diode pumped Nd:YAG lasers; Laser diode reiki Nd:YAG lasear

    Energy Technology Data Exchange (ETDEWEB)

    Yuasa, H.; Akiyama, Y.; Nakayama, M. [Toshiba Corp., Tokyo (Japan)

    2000-04-01

    Laser-diode pumped Nd:YAG lasers are expected to be applied to laser processing fields such as welding, cutting, drilling, and marking due to their potential for high efficiency and compactness. We are designing and developing laser-diode pumped Nd:YAG lasers using numerical analysis simulation techniques such as ray tracing and thermal analysis. We have succeeded in achieving a laser power of more than 3 kW with 20% efficiency, which is the best ever obtained. In addition, we have developed a laser-diode pumped green laser by second harmonic generation, for precision machining on silicon wafers. (author)

  14. Laser Safety Inspection Criteria

    International Nuclear Information System (INIS)

    Barat, K.

    2005-01-01

    A responsibility of the Laser Safety Officer (LSO) is to perform laser audits. The American National Standard Z136.1 Safe Use of Lasers references this requirement through several sections. One such reference is Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''. The composition, frequency and rigor of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms It is common for audit findings from one inspector or inspection to the next to vary even when reviewing the same material. How often has one heard a comment, ''well this area has been inspected several times over the years and no one ever said this or that was a problem before''. A great number of audit items, and therefore findings, are subjective because they are based on the experience and interest of the auditor to particular items on the checklist. Beam block usage, to one set of eyes might be completely adequate, while to another, inadequate. In order to provide consistency, the Laser Safety Office of the National Ignition Facility Directorate has established criteria for a number of items found on the typical laser safety audit form. The criteria are distributed to laser users. It serves two broad purposes; first, it gives the user an expectation of what will be reviewed by an auditor. Second, it is an opportunity to explain audit items to the laser user and thus the reasons for some of these items, such as labelling of beam blocks

  15. Laser requirements for a laser fusion energy power plant

    Institute of Scientific and Technical Information of China (English)

    Stephen; E.Bodner; Andrew; J.Schmitt; John; D.Sethian

    2013-01-01

    We will review some of the requirements for a laser that would be used with a laser fusion energy power plant, including frequency, spatial beam smoothing, bandwidth, temporal pulse shaping, efficiency, repetition rate, and reliability. The lowest risk and optimum approach uses a krypton fluoride gas laser. A diode-pumped solid-state laser is a possible contender.

  16. El láser y la fotónica en la Cirugía Plástica española e iberoamericana: Antecedentes históricos, aplicaciones actuales y proyectos de desarrollo inmediato Laser and photonics in Plastic Surgery in Spain and Latinamerica: Historical background, current applications and proyects of inmediate development

    Directory of Open Access Journals (Sweden)

    P.A. Martínez-Carpio

    2010-03-01

    Full Text Available La sociedad moderna valora y demanda los tratamientos láser por encima de otras posibilidades. En Cirugía Plástica los tratamientos fototerápicos y el láser se utilizan rutinariamente para combatir la diversa amalgama de signos senescentes de la piel. También, como herramienta ocasionalmente ventajosa en cirugía incisional, estética, óculo-plástica y reconstructiva. En esta revisión se plantea un panorama ecléctico sobre las posibilidades actuales del láser en el dominio del cirujano plástico, diferenciando un modelo reduccionista y un modelo integrador en el abordaje especializado de la Fotónica Médica y la Cirugía Láser. Se destaca la labor de la Sociedad Española de Láser Médico-Quirúrgico como nexo de unión entre Europa e Iberoamérica en la investigación, docencia y asistencia en esta materia.Modern society values and demands laser treatment above other therapeutical options. In Plastic Surgery, phototherapy treatments and lasers are used on a day to day basis against the broad amalgam of signs of aging skin. Sometimes they are also used as an advantageous instrument in incisional, aesthetic, oculoplastic and reconstructive surgery. In this review, we offer an eclectic overview of the current possibilities for laser applications in Plastic Surgery, defining a model in which the surgeon can integrate all of the available offer in Medical Photonics and Laser Surgery not merely based on the use of laser. We highlight the role of the Spanish Society of Medical Surgical Laser as a link between Europe and Latinamerica in research, teaching and assistance in this field.

  17. Measurements of laser parameters for the Shiva laser fusion facility

    International Nuclear Information System (INIS)

    Ozarski, R.G.

    1979-01-01

    Large laser systems require numerous laser diagnostics to provide configuration, performance and maintenance data to permit efficient operation. The following diagnostics for a large laser system named Shiva are discussed: (1) description of Shiva laser system, (2) what measurements are desired and or required and why, (3) what measurement techniques and packages are employed and a brief description of the operating principles of the sensors employed, and (4) the laser diagnostic data acquisition and display system

  18. LASER PROCESSING ON SINGLE CRYSTALS BY UV PULSE LASER

    OpenAIRE

    龍見, 雅美; 佐々木, 徹; 高山, 恭宜

    2009-01-01

    Laser processing by using UV pulsed laser was carried out on single crystal such as sapphire and diamond in order to understand the fundamental laser processing on single crystal. The absorption edges of diamond and sapphire are longer and shorter than the wave length of UV laser, respectively. The processed regions by laser with near threshold power of processing show quite different state in each crystal.

  19. Laser diode technology and applications

    International Nuclear Information System (INIS)

    Figueroa, L.

    1989-01-01

    This book covers a wide range of semiconductor laser technology, from new laser structures and laser design to applications in communications, remote sensing, and optoelectronics. The authors report on new laser diode physics and applications and present a survey of the state of the art as well as progress in new developments

  20. 1982 laser program annual report

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, C.D.; Grow, G.R. (eds.)

    1983-08-01

    This annual report covers the following eight sections: (1) laser program review, (2) laser systems and operation, (3) target design, (4) target fabrication, (5) fusion experiments program, (6) Zeus laser project, (7) laser research and development, and (8) energy applications. (MOW)

  1. Fractional laser skin resurfacing.

    Science.gov (United States)

    Alexiades-Armenakas, Macrene R; Dover, Jeffrey S; Arndt, Kenneth A

    2012-11-01

    Laser skin resurfacing (LSR) has evolved over the past 2 decades from traditional ablative to fractional nonablative and fractional ablative resurfacing. Traditional ablative LSR was highly effective in reducing rhytides, photoaging, and acne scarring but was associated with significant side effects and complications. In contrast, nonablative LSR was very safe but failed to deliver consistent clinical improvement. Fractional LSR has achieved the middle ground; it combined the efficacy of traditional LSR with the safety of nonablative modalities. The first fractional laser was a nonablative erbium-doped yttrium aluminum garnet (Er:YAG) laser that produced microscopic columns of thermal injury in the epidermis and upper dermis. Heralding an entirely new concept of laser energy delivery, it delivered the laser beam in microarrays. It resulted in microscopic columns of treated tissue and intervening areas of untreated skin, which yielded rapid reepithelialization. Fractional delivery was quickly applied to ablative wavelengths such as carbon dioxide, Er:YAG, and yttrium scandium gallium garnet (2,790 nm), providing more significant clinical outcomes. Adjustable laser parameters, including power, pitch, dwell time, and spot density, allowed for precise determination of percent surface area, affected penetration depth, and clinical recovery time and efficacy. Fractional LSR has been a significant advance to the laser field, striking the balance between safety and efficacy.

  2. The argon excimer laser

    International Nuclear Information System (INIS)

    Wrobel, W.G.

    1981-02-01

    The electron-beam-pumped argon eximer laser is investigated and tuned for the first time. The electron beam is generated by means of an improved coaxial field emmision diode in which argon gas is excited with power densities of 0.3 GW/cm 3 for 18 ns. The processes in the excited gas of 20 to 65 bar are described in the context of a kinetic model as a sequence of stationary states. Investigations of the amplified spontaneous emission (superfluorescence) confirm the predictions of this model. Only the absorption due to the excited Ar atoms is anomalously high. Reproducible operation of the argon eximer laser was achieved in a wide pressure range with various resonator arrangements. The wavelength of this shortest wavelength of this shortest wavelength excimer laser is 126 nm, the laser line width approx. 1.7 nm, the pulse length 7 to 13 ns, and the laser power 250 kW. The laser emission is tuned from 123.2 nm to 128.4 nm by two different methods (diffraction grating and prism). This tunable laser is thus the one with the shortest wavelength at present. Its line width is 0.25 to 0.4 nm, and the power ue 1.7 kW. (orig.)

  3. Laser wakefield acceleration

    International Nuclear Information System (INIS)

    Esarey, E.; Ting, A.; Sprangle, P.

    1989-01-01

    The laser wakefield accelerator (LWFA) is a novel plasma based electron acceleration scheme which utilizes a relativistic optical guiding mechanism for laser pulse propagation. In the LWFA, a short, high power, single frequency laser pulse is propagated through a plasma. As the laser pulse propagates, its radial and axial ponderomotive forces nonresonantly generate large amplitude plasma waves (wakefields) with a phase velocity equal to the group velocity of the pulse. A properly phased electron bunch may then be accelerated by the axial wakefield and focused by the transverse wakefield. Optical guiding of the laser pulse in the plasma is necessary in order to achieve high energies in a single stage of acceleration. At sufficiently high laser powers, optical guiding may be achieved through relativistic effects associated with the plasma electrons. Preliminary analysis indicates that this scheme may overcome some of the difficulties present in the plasma beat wave accelerator and in the plasma wakefield accelerator. Analytical and numerical calculations are presented which study both laser pulse propagation within a plasma as well as the subsequent generation of large amplitude plasma waves. In addition, the generation of large amplitude plasma waves in regimes where the plasma waves become highly nonlinear is examined

  4. Excimer laser decontamination

    Science.gov (United States)

    Sentis, Marc L.; Delaporte, Philippe C.; Marine, Wladimir; Uteza, Olivier P.

    2000-04-01

    The application of excimer laser ablation process to the decontamination of radioactive surfaces is discussed. This technology is very attractive because it allows to efficiently remove the contaminated particles without secondary waste production. To demonstrate the capability of such technology to efficiently decontaminate large area, we studied and developed a prototype which include a XeCl laser, an optical fiber delivery system and an ablated particles collection cell. The main physical processes taking place during UV laser ablation will be explained. The influence of laser wavelength, pulse duration and absorption coefficient of material will be discussed. Special studies have been performed to understand the processes which limit the transmission of high average power excimer laser through optical fiber, and to determine the laser conditions to optimize the value of this transmission. An in-situ spectroscopic analysis of laser ablation plasma allows the real time control of the decontamination. The results obtained for painting or metallic oxides removal from stainless steel surfaces will be presented.

  5. Color Laser Microscope

    Science.gov (United States)

    Awamura, D.; Ode, T.; Yonezawa, M.

    1987-04-01

    A color laser microscope utilizing a new color laser imaging system has been developed for the visual inspection of semiconductors. The light source, produced by three lasers (Red; He-Ne, Green; Ar, Blue; He-Cd), is deflected horizontally by an AOD (Acoustic Optical Deflector) and vertically by a vibration mirror. The laser beam is focused in a small spot which is scanned over the sample at high speed. The light reflected back from the sample is reformed to contain linear information by returning to the original vibration mirror. The linear light is guided to the CCD image sensor where it is converted into a video signal. Individual CCD image sensors are used for each of the three R, G, or B color image signals. The confocal optical system with its laser light source yields a color TV monitor image with no flaring and a much sharper resolution than that of the conventional optical microscope. The AOD makes possible a high speed laser scan and a NTSC or PAL TV video signal is produced in real time without any video memory. Since the light source is composed of R, G, and B laser beams, color separation superior to that of white light illumination is achieved. Because of the photometric linearity of the image detector, the R, G, and B outputs of the system are most suitably used for hue analysis. The CCD linear image sensors in the optical system produce no geometrical distortion, and good color registration is available principally. The output signal can be used for high accuracy line width measuring. The many features of the color laser microscope make it ideally suited for the visual inspection of semiconductor processing. A number of these systems have already been installed in such a capacity. The Color Laser Microscope can also be a very useful tool for the fields of material engineering and biotechnology.

  6. Dye laser principles with applications

    CERN Document Server

    Duarte, Frank J; Liao, Peter F; Kelley, Paul

    1990-01-01

    A tutorial introduction to the field of dye lasers, Dye Laser Principles also serves as an up-to-date overview for those using dye lasers as research and industrial tools. A number of the issues discussed in this book are pertinent not only to dye lasers but also to lasers in general. Most of the chapters in the book contain problem sets that expand on the material covered in the chapter.Key Features* Dye lasers are among the most versatile and successful laser sources currently available in use Offering both pulsed and continuous-wave operation and tunable from the near ultraviole

  7. Temperature stabilization of injection lasers

    International Nuclear Information System (INIS)

    Albanese, A.

    1987-01-01

    Apparatus which stabilizes the temperature, and thereby the output wavelength, of an injection laser. Means monitor the laser terminal voltage across a laser and derive a voltage therefrom which is proportional to the junction voltage of the laser. Means compares the voltage to a reference value from source and a temperature controller adjusts the laser temperature in response to the results of the comparison. Further embodiments of the present invention vary the output wavelength of the laser by varying the reference value from source against which the laser junction voltage is compared. (author)

  8. Latest development of laser cutting

    OpenAIRE

    Wetzig, Andreas; Herwig, Patrick; Hauptmann, Jan; Goppold, Cindy; Baumann, Robert; Fürst, Andreas; Rose, Michael; Pinder, Thomas; Mahrle, Achim; Beyer, Eckhard

    2016-01-01

    Laser cutting was one of the first applications of laser material processing. Today, laser cutting is the most widespread application among laser material processing besides laser marking. Meanwhile, nearly each material can be cut by means of a laser, in particular since ultra short pulse lasers are available in the power range of up to 100 W. The to be cut material can come with thicknesses from a few microns till tens of millimeters as flat stock or as free form shapes. The paper will conc...

  9. Color speckle in laser displays

    Science.gov (United States)

    Kuroda, Kazuo

    2015-07-01

    At the beginning of this century, lighting technology has been shifted from discharge lamps, fluorescent lamps and electric bulbs to solid-state lighting. Current solid-state lighting is based on the light emitting diodes (LED) technology, but the laser lighting technology is developing rapidly, such as, laser cinema projectors, laser TVs, laser head-up displays, laser head mounted displays, and laser headlamps for motor vehicles. One of the main issues of laser displays is the reduction of speckle noise1). For the monochromatic laser light, speckle is random interference pattern on the image plane (retina for human observer). For laser displays, RGB (red-green-blue) lasers form speckle patterns independently, which results in random distribution of chromaticity, called color speckle2).

  10. Teradiode's high brightness semiconductor lasers

    Science.gov (United States)

    Huang, Robin K.; Chann, Bien; Burgess, James; Lochman, Bryan; Zhou, Wang; Cruz, Mike; Cook, Rob; Dugmore, Dan; Shattuck, Jeff; Tayebati, Parviz

    2016-03-01

    TeraDiode is manufacturing multi-kW-class ultra-high brightness fiber-coupled direct diode lasers for industrial applications. A fiber-coupled direct diode laser with a power level of 4,680 W from a 100 μm core diameter, BPP) of 3.5 mm-mrad and is the lowest BPP multi-kW-class direct diode laser yet reported. This laser is suitable for industrial materials processing applications, including sheet metal cutting and welding. This 4-kW fiber-coupled direct diode laser has comparable brightness to that of industrial fiber lasers and CO2 lasers, and is over 10x brighter than state-of-the-art direct diode lasers. We have also demonstrated novel high peak power lasers and high brightness Mid-Infrared Lasers.

  11. Organic solid-state lasers

    CERN Document Server

    Forget, Sébastien

    2013-01-01

    Organic lasers are broadly tunable coherent sources, potentially compact, convenient and manufactured at low-costs. Appeared in the mid 60’s as solid-state alternatives for liquid dye lasers, they recently gained a new dimension after the demonstration of organic semiconductor lasers in the 90's. More recently, new perspectives appeared at the nanoscale, with organic polariton and surface plasmon lasers. After a brief reminder to laser physics, a first chapter exposes what makes organic solid-state organic lasers specific. The laser architectures used in organic lasers are then reviewed, with a state-of-the-art review of the performances of devices with regard to output power, threshold, lifetime, beam quality etc. A survey of the recent trends in the field is given, highlighting the latest developments with a special focus on the challenges remaining for achieving direct electrical pumping of organic semiconductor lasers. A last chapter covers the applications of organic solid-state lasers.

  12. Laser Hazards Bibliography

    Science.gov (United States)

    1989-10-31

    light on mandibular fracture healing, Stomatologiia, 57(5): 5-9 (1978). 42 Laser Hazards Bibliography 177. Van Gemert, M.J.C., Schets, G.A.C.M., Bishop...U., Laser-coagulation of ruptured fixation suture after lens implantation, J Am Intraocul Implant Soc, 4(2): 54 (1978). 49. Federman, J. L., Ando, F...laser in pediatric surgery, J Ped Surg, 3: 263-270 (April 1968). 82. Hennessy, R. T., and Leibowitz, H., Subjective measurement of accommodation with

  13. Optimising laser tattoo removal

    Directory of Open Access Journals (Sweden)

    Kabir Sardana

    2015-01-01

    Full Text Available Lasers are the standard modality for tattoo removal. Though there are various factors that determine the results, we have divided them into three logical headings, laser dependant factors such as type of laser and beam modifications, tattoo dependent factors like size and depth, colour of pigment and lastly host dependent factors, which includes primarily the presence of a robust immune response. Modifications in the existing techniques may help in better clinical outcome with minimal risk of complications. This article provides an insight into some of these techniques along with a detailed account of the factors involved in tattoo removal.

  14. Ultrashort Laser Pulse Phenomena

    CERN Document Server

    Diels, Jean-Claude

    2006-01-01

    Ultrashort Laser Pulse Phenomena, 2e serves as an introduction to the phenomena of ultra short laser pulses and describes how this technology can be used to examine problems in areas such as electromagnetism, optics, and quantum mechanics. Ultrashort Laser Pulse Phenomena combines theoretical backgrounds and experimental techniques and will serve as a manual on designing and constructing femtosecond (""faster than electronics"") systems or experiments from scratch. Beyond the simple optical system, the various sources of ultrashort pulses are presented, again with emphasis on the basic

  15. Laser-driven accelerators

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    Several devices for using laser fields have been proposed and they can be classified in three broad categories - 'far-field' accelerators (such as the principle of inverse free electron lasers), 'media' accelerators (which, for example, use the inverse Cherenkov effect or laser-controlled plasma waves), and 'near-field' accelerators (using a loaded guiding structure such as cavities or gratings). These different approaches come from the fact that a particle cannot be accelerated by the absorption of single photons (because of momentum conservation) and thus some other element has to intervene. (orig./HSI).

  16. Regenerative laser system

    International Nuclear Information System (INIS)

    Biancardi, F.R.; Landerman, A.; Melikian, G.

    1975-01-01

    Regenerative apparatus for exhausting the working medium from the optical cavity of a laser and for supplying preheated diluent to the reaction chamber of a laser is disclosed. In an aftercooler thermal energy is exchanged between the working medium exhausted from the optical cavity and a cryogenic coolant which is subsequently utilized as the motive fluid for an ejector and as a diluent in the production of laser gas. Highly toxic and corrosive gases are condensed out of the working medium as the cryogenic coolant is evaporated and superheated. A preheater transfers additional heat to the diluent before the diluent enters the reaction chamber. (U.S.)

  17. Tunable excimer lasers

    International Nuclear Information System (INIS)

    Sze, R.C.

    1990-01-01

    The wide bandwidth nature of the rare-gas halide excimer transitions allow reasonable tuning of the laser oscillation wavelength that makes it useful for a number of applications. At the same time this wide bandwidth makes narrow band operation difficult and special techniques are needed to insure narrow frequency lasing as well as absolute frequency resettability. The author discusses briefly some of the classical frequency narrowing techniques and then goes on to some recent work that require lasers of special frequency characteristics for special applications including KrF laser fusion

  18. Diatomic gasdynamic lasers.

    Science.gov (United States)

    Mckenzie, R. L.

    1972-01-01

    Predictions from a numerical model of the vibrational relaxation of anharmonic diatomic oscillators in supersonic expansions are used to show the extent to which the small anharmonicity of gases like CO can cause significant overpopulations of upper vibrational states. When mixtures of CO and N2 are considered, radiative gain on many of the vibration-rotation transitions of CO is predicted. Experiments are described that qualitatively verify the predictions by demonstrating laser oscillation in CO-N2 expansions. The resulting CO-N2 gasdynamic laser displays performance characteristics that equal or exceed those of similar CO2 lasers.

  19. Gas dynamic lasers

    International Nuclear Information System (INIS)

    Hill, R.J.; Jewell, N.T.

    1975-01-01

    In a high powered laser system it is proposed that combustion gases be bled off from a gas turbine engine and their composition adjusted by burning extra fuel in the bleed gases or adding extra substances. Suitable aerodynamic expansion produces a population inversion resulting in laser action in the CO 2 species. Alternatively, bleed gases may be taken from the high pressure compressor of the gas turbine engine and an appropriate fuel burned therein. If required, other adjustments may also be made to the composition and the resulting gaseous mixture subjected to aerodynamic expansion to induce laser action as before. (auth)

  20. Monoenergetic laser wakefield acceleration

    Directory of Open Access Journals (Sweden)

    N. E. Andreev

    2000-02-01

    Full Text Available Three dimensional test particle simulations are applied to optimization of the plasma-channeled laser wakefield accelerator (LWFA operating in a weakly nonlinear regime. Electron beam energy spread, emittance, and luminosity depend upon the proportion of the electron bunch size to the plasma wavelength. This proportion tends to improve with the laser wavelength increase. We simulate a prospective two-stage ∼1GeV LWFA with controlled energy spread and emittance. The input parameters correspond to realistic capabilities of the BNL Accelerator Test Facility that features a picosecond-terawatt CO_{2} laser and a high-brightness electron gun.

  1. Simulations of laser undulators

    Science.gov (United States)

    Milton, S. V.; Biedron, S. B.; Einstein, J. E.

    2016-09-01

    We perform a series of single-pass, one-D free-electron laser simulations based on an electron beam from a standard linear accelerator coupled with a so-called laser undulator, a specialized device that is more compact than a standard undulator based on magnetic materials. The longitudinal field profiles of such lasers undulators are intriguing as one must and can tailor the profile for the needs of creating the virtual undulator. We present and discuss several results of recent simulations and our future steps.

  2. Diatomic gasdynamic lasers

    International Nuclear Information System (INIS)

    McKenzie, R.L.

    1971-12-01

    Predictions from a numerical model of the vibrational relaxation of anharmonic diatomic oscillators in supersonic expansions are used to show the extent to which the small anharmonicity of gases like CO can cause significant over-populations of upper vibrational states. When mixtures of CO and N 2 are considered, radiative gain on many of the vibration-rotation transitions of CO is predicted. Experiments are described that qualitatively verify the predictions by demonstrating laser oscillation in CO-N 2 expansions. The resulting CO-N 2 gasdynamic laser displays performance characteristics that equal or exceed those of similar CO 2 lasers

  3. High power excimer laser

    International Nuclear Information System (INIS)

    Oesterlin, P.; Muckenheim, W.; Basting, D.

    1988-01-01

    Excimer lasers emitting more than 200 W output power are not commercially available. A significant increase requires new technological efforts with respect to both the gas circulation and the discharge system. The authors report how a research project has yielded a laser which emits 0.5 kW at 308 nm when being UV preionized and operated at a repetition rate of 300 Hz. The laser, which is capable of operating at 500 Hz, can be equipped with an x-ray preionization module. After completing this project 1 kW output power will be available

  4. Plasmonic colour laser printing

    DEFF Research Database (Denmark)

    Zhu, Xiaolong; Vannahme, Christoph; Højlund-Nielsen, Emil

    2016-01-01

    -beam lithography (EBL) or focused ion beam (FIB), both expensive and not scalable processes that are not suitable for post-processing customization. Here we show a method of colour printing on nanoimprinted plasmonic metasurfaces using laser post-writing. Laser pulses induce transient local heat generation...... that leads to melting and reshaping of the imprinted nanostructures. Depending on the laser pulse energy density, different surface morphologies that support different plasmonic resonances leading to different colour appearances can be created. Using this technique we can print all primary colours...

  5. Optimising Laser Tattoo Removal

    Science.gov (United States)

    Sardana, Kabir; Ranjan, Rashmi; Ghunawat, Sneha

    2015-01-01

    Lasers are the standard modality for tattoo removal. Though there are various factors that determine the results, we have divided them into three logical headings, laser dependant factors such as type of laser and beam modifications, tattoo dependent factors like size and depth, colour of pigment and lastly host dependent factors, which includes primarily the presence of a robust immune response. Modifications in the existing techniques may help in better clinical outcome with minimal risk of complications. This article provides an insight into some of these techniques along with a detailed account of the factors involved in tattoo removal. PMID:25949018

  6. Laser welding engineering

    International Nuclear Information System (INIS)

    Bhieh, N. M.; El Eesawi, M. E.; Hashkel, A. E.

    2007-01-01

    Laser welding was in its early life used mainly for unusual applications where no other welding process would be suitable that was twenty five years ago. Today, laser welding is a fully developed part of the metal working industry, routinely producing welds for common items such as cigarette lighters, which springs, motor/transformer lamination, hermetic seals, battery and pacemaker cans and hybrid circuit packages. Yet very few manufacturing engineering have seriously considers employing lasers in their own operations. Why? There are many reasons, but a main one must be not acquainted with the operation and capabilities of a laser system. Other reasons, such as a relatively high initial cost and a concern about using lasers in the manufacturing environment, also are frequently cited, and the complexity of the component and flexibility of the light delivery system. Laser welding could be used in place of many different standard processes, such as resistance (spot or seam), submerged arc, RF induction, high-frequency resistance, ultrasonic and electronic and electron-beam. while each of these techniques has established an independent function in the manufacturing world, the flexible laser welding approach will operate efficiently and economically in many different applications. Its flexibility will even permit the welding system to be used for other machining function, such as drilling, scribing, sealing and serializing. In this article, we will look at how laser welding works and what benefits it can offer to manufacturing engineers. Some industry observers state that there are already 2,000 laser machine tools being used for cutting, welding and drilling and that the number could reach 30,000 over the next 15 years as manufacturing engineers become more aware of the capabilities of lasers [1). While most laser applications are dedicated to one product or process that involves high-volume, long-run manufacturing, the flexibility of a laser to supply energy to hard

  7. Laser Megajoule synchronization system

    International Nuclear Information System (INIS)

    Luttmann, M.; Pastor, J.F; Drouet, V.; Prat, M.; Raimbourg, J.; Adolf, A.

    2011-01-01

    This paper describes the synchronisation system under development on the Laser Megajoule (LMJ) in order to synchronize the laser quads on the target to better than 40 ps rms. Our architecture is based on a Timing System (TS) which delivers trigger signals with jitter down to 15 ps rms coupled with an ultra precision timing system with 5 ps rms jitter. In addition to TS, a sensor placed at the target chamber center measures the arrival times of the 3 omega nano joule laser pulses generated by front end shots. (authors)

  8. New Frontiers for Non-Destructive Testing in the Nuclear Age; Perspectives des Essais Non Destructifs a l'Ere Nucleaire; ''Novye rubezhi'' nedestruktivnykh ispytanij v yadernyj vek; Nuevas Posibilidades de los Ensayos No Destructivos en la Era Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Ballard, D. W. [Sandia Laboratory Albuquerque, NM (United States)

    1965-10-15

    electromagneticos, se establecen otros nuevos para comprobar si el equipo retine los requisitos necesarios tanto en e l aspecto estatico como en el dinamico. Esos metodos ultrarrapidos y de elevado poder de resolucion constituyen en realidad las nuevas fronteras del ensayo no destructivo, y a ellos se refiere fundamentalmente la presente memoria. Entre los modernos metodos de ensayo que se estudian se cuenta el uso de rayos infrarrojos para verificar el estado de las soldaduras y la inspeccion cinematorradiografica de las estructuras durante los ensayos de vibracion para verificar su comportamiento dinamico. Hay que tener tambien muy en cuenta la importancia de una localizacion eficaz de los escapes para que el combustible de los reactores pueda utilizarse en condiciones de seguridad. Se examina un metodo de inspeccion de piezas revestidas, basado en el empleo de gas radiactivo, con el que se pueden medir fugas de incluso 10{sup -12} cm{sup 3}/s, esto es, de 1 cm{sup 3} cada 500 anos. Otro medio eficaz que puede utilizarse actualmente es la radiografia dinamica con gran ampliacion, basada en el uso de tubos vidicon sensibles a los rayos X. Se estudia asimismo un nuevo metodo analogo al indicado, (cinesonograffa); con este metodo, la obtencion de imagenes se realiza por medios ultrasonicos y no radiograficos. Para terminar, se procura estudiar el equipo totalmente automatico y ultrarrapido que habra de prepararse para exploracion a gran velocidad. Ese equipo supone la aplicacion simultanea de varios metodos de ensayo no destructivo. Los metodos basados en el empleo de rayos infrarrojos, los electromagneticos y los de microondas combinados con la exploracion gobernada por cinta magnetica se utilizan para obtener imagenes de la produccion; esas imagenes pueden ser televisadas o registradas a distancia. Se examinan los parametros de ensayo, las posibilidades de indicacion y los sistemas de comprobacion continua. Esas posibilidades se han estudiado ya en laboratorio y ahora hay que

  9. Laser applications in neurosurgery

    Science.gov (United States)

    Cerullo, Leonard J.

    1985-09-01

    The "false start" of the laser in neurosurgery should not be misconstrued as a denial of the inherent advantages of precision and gentleness in dealing with neural tissue. Rather, early investigators were frustrated by unrealistic expectations, cumbersome equipment, and a general ignorance of microtechnique. By the early 70s, microneurosurgery was well established, surgical laser equipment for free hand and microlinked application had been developed, and a more realistic view of the limitations of the laser had been established. Consequently, the late 70s really heralded the renaissance of the laser in neurosurgery. Since then, there has been an overwhelming acceptance of the tool in a variety of clinical situations, broadly categorized in five groups. 1)|Perhaps the most generally accepted area is in the removal of extra-axial tumors of the brain and spinal cord. These tumors, benign by histology but treacherous by location, do not present until a significant amount of neurological compensation has already occurred. The application of additional trauma to the neural tissue, whether by further tumor growth or surgical manipulation, frequently results in irreversible damage. Here, the ability of the laser to vaporize tissue, in a fairly hemostatic fashion, without mechanical or thermal damage to sensitive surrounding tissues, is essential. 2)|The ability to incise delicate neural tissue with minimal spread of thermal destruction to adjacent functioning tissue makes the laser the ideal instrument when tumors deep under the surface are encountered in the brain or spinal cord. Thus, the second group of applications is in the transgression of normal neural structures to arrive at deeper pathological tissue. 3)|The third area of benefit for the laser in neurosurgery has been in the performance of neuroablative procedures, calling for deliberate destruction of functioning neural tissue in a controlled fashion. Again, the precision and shape confinement of the destructive

  10. Laser tests of silicon detectors

    International Nuclear Information System (INIS)

    Dolezal, Zdenek; Escobar, Carlos; Gadomski, Szymon; Garcia, Carmen; Gonzalez, Sergio; Kodys, Peter; Kubik, Petr; Lacasta, Carlos; Marti, Salvador; Mitsou, Vasiliki A.; Moorhead, Gareth F.; Phillips, Peter W.; Reznicek, Pavel; Slavik, Radan

    2007-01-01

    This paper collects experiences from the development of a silicon sensor laser testing setup and from tests of silicon strip modules (ATLAS End-cap SCT), pixel modules (DEPFET) and large-area diodes using semiconductor lasers. Lasers of 1060 and 680 nm wavelengths were used. A sophisticated method of focusing the laser was developed. Timing and interstrip properties of modules were measured. Analysis of optical effects involved and detailed discussion about the usability of laser testing for particle detectors are presented

  11. Desarrollo de la Hematología en Cuba. Perspectivas y posibilidades de colaboración regional e internacional: Perspectives and possibilities of regional and international cooperation Development of the Hematology in Cuba

    Directory of Open Access Journals (Sweden)

    José M. Ballester-Santovenia

    2011-03-01

    Full Text Available Desde la fundación en 1966, del Instituto de Hematología e Inmunología (IHI, centro rector de la especialidad en Cuba, se ha trabajado intensamente en la búsqueda y aplicación de los protocolos de tratamiento más actuales y la introducción de innovaciones tecnológicas para el diagnóstico y tratamiento de pacientes con hemopatías, lo que ha permitido alcanzar niveles de curación similares a los de países desarrollados, en enfermedades como la leucemia linfoide aguda en niños, y se ha logrado la aplicación de estos protocolos en todos los servicios de hematología del país. Con la atención integral a los pacientes hemofílicos y con anemia drepanocítica, se ha elevado su expectativa de vida con una calidad de vida superior. Se han formado especialistas para todo el Sistema Nacional de Salud (SNS, así como enfermeras, técnicos y otros profesionales vinculados con la especialidad, que también realizan colaboración en diversos países. El nivel alcanzado ha permitido la contribución, de manera relevante, en el desarrollo del trasplante de médula ósea, y en el campo de la Medicina Regenerativa se ha logrado introducir el autotrasplante con células madre en varias enfermedades, en lo que ya participan diferentes centros del país. La seguridad de la sangre y la garantía de su calidad ha sido objetivo determinante en la Medicina Transfusional, que es vital para todas las ramas de las ciencias médicas. Esta labor y los resultados exitosos obtenidos, han posibilitado la integración de una red nacional de servicios de hematología que contribuye decisivamente al fortalecimiento del SNS y es ejemplo destacado de los logros de la medicina revolucionaria. Esta experiencia abre posibilidades para incrementar la colaboración internacional y fundamentalmente, para la integración con otros países, principalmente de nuestra región, que contribuya a optimizar los niveles de salud y mejorar la calidad de vida de nuestros pueblos

  12. A Hermenêutica no Campo Organizacional: duas possibilidades interpretativistas de pesquisaHermeneutic Questions in Organizational Studies: two interpretative possibilities for researchHermenéutica en el Campo Organizacional: dos posibilidades interpretativas en la investigación

    Directory of Open Access Journals (Sweden)

    VIEIRA, Almir Martins

    2012-09-01

    , by the presentations of reported theoretical assumptions, the relevance of the interpretative perspective for the conduction of research that has the organization as object of study, in the pursuit of the identification of ways of constructing the social reality that is the result of the analysis of meanings and experiences lived by the participants, highlighting the importance of the bond between researcher and the research object The theoretical discussion regarding the two perspectives allows to observe the competence of the phenomenological and ethnographic research practice within the field of organizational studies, showing their methodological possibilities to identify dynamics that relate to the experience of life, favoring the analysis of the human being as a phenomenon of interpretation.RESUMENEste ensayo presenta consideraciones teóricas sobre dos tipos de estrategias de investigación: fenomenología y etnografía. Apoyados en la perspectiva hermenéutica, se presentan proposiciones conceptuales de las dos vertientes. La primera se estudia dentro del contexto sociológico y la segunda se presenta con bases antropológicas. Sus usos similares en el contexto organizacional – como también sus diferencias – se cuestionan según la contribución, la presentación de los presupuestos teóricos relatados, la adecuación de la propuesta interpretativa para conseguir investigaciones centradas en la organización como objeto de estudio, identificando formas de construcción de la realidad social resultante del análisis de significados y experiencias vividas por sus participantes, destacando la importancia de que investigador e investigado se involucren. El debate teórico respecto a las dos vertientes permitió reflejar la adecuación de la práctica de investigaciones fenomenológicas y etnográficas en el campo de los estudios organizacionales, manifestándose como posibilidades metodológicas para identificar dinámicas vinculadas a la experiencia de vida

  13. Multispot fiber laser welding

    DEFF Research Database (Denmark)

    Schutt Hansen, Klaus

    This dissertation presents work and results achieved in the field of multi beam fiber laser welding. The project has had a practical approach, in which simulations and modelling have been kept at a minimum. Different methods to produce spot patterns with high power single mode fiber lasers have...... been examined and evaluated. It is found that both diamond turned DOE’s in zinc sulphide and multilevel etched DOE’s (Diffractive Optical Elements) in fused silica have a good performance. Welding with multiple beams in a butt joint configuration has been tested. Results are presented, showing it has...... been possible to control the welding width in incremental steps by adding more beams in a row. The laser power was used to independently control the keyhole and consequently the depth of fusion. An example of inline repair of a laser weld in butt joint configuration was examined. Zinc powder was placed...

  14. Lasers and holography

    CERN Document Server

    Kock, Winston E

    1981-01-01

    Accessible, illustrated introduction covers wave patterns and coherence, summarizes the development of lasers and the phenomenon of wave diffraction, and describes zone plates and properties of holograms. 1981 edition.

  15. Jupiter Laser Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Jupiter Laser Facility is an institutional user facility in the Physical and Life Sciences Directorate at LLNL. The facility is designed to provide a high degree...

  16. Blackbody metamaterial lasers

    KAUST Repository

    Liu, Changxu

    2015-01-01

    We investigate both theoretically and experimentally a new type of laser, which exploits a broadband light "condensation" process sustained by the stimulated amplification of an optical blackbody metamaterial. © 2014 Optical Society of America.

  17. Electra Laser Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: The Electra Laser Facility is used to develop the science and technology needed to develop a reliable, efficient, high-energy, repetitively pulsed krypton...

  18. Airclad fiber laser technology

    DEFF Research Database (Denmark)

    Hansen, Kim P.; Olausson, Christina Bjarnal Thulin; Broeng, Jes

    2011-01-01

    High-power fiber lasers and amplifiers have gained tremendous momentum in the last 5 years. Many of the traditional manufacturers of gas and solid-state lasers are now pursuing the fiber-based systems, which are displacing the conventional technology in many areas. High-power fiber laser systems...... require reliable fibers with large cores, stable mode quality, and good power handling capabilities-requirements that are all met by the airclad fiber technology. In the present paper we go through many of the building blocks needed to build high-power systems and we show an example of a complete airclad...... laser system. We present the latest advancements within airclad fiber technology including a new 100 m single-mode polarization-maintaining rod-type fiber capable of amplifying to megawatt power levels. Furthermore, we describe the novel airclad-based pump combiners and their use in a completely...

  19. Laser fusion overview

    International Nuclear Information System (INIS)

    Nuckolls, J.

    1976-01-01

    Because of recent breakthroughs in the target area, and in the glass laser area, the scientific feasibility of laser fusion--and of inertial fusion--may be demonstrated in the early 1980's. Then the development in that time period of a suitable laser (or storage ring or other driving source) would make possible an operational inertial fusion reactor in this century. These are roughly the same time scales as projected by the Tokamak magnetic confinement approach. It thus appears that the 15-20 year earlier start by magnetic confinement fusion may be overcome. Because inertial confinement has been demonstrated, and inertial fusion reactors may operate on smaller scales than Tokamaks, laser fusion may have important technical and economic advantages

  20. Laser therapy for periodontitis

    Science.gov (United States)

    Efanov, O. I.

    2001-04-01

    An investigation was made of applying pulsed (lambda) equals 0.89 micrometers laser radiation in the treatment for early diagnosed periodontitis. The investigation was made on 65 patients (47 patients constituted the experimental group and 18 patients constituted a control group) affected by periodontitis. Clinical and functional tests revealed that laser therapy produced a string effect on the course of the illness. It reduced bleeding, inflammation, and pruritus. However, it did not produce an affect on electroexcitation. Biomicroscopic examinations and periodontium rheography revealed that the gingival blood flow became normal after the course of laser therapy. The capillary permeability and venous congestion decreased, which was confirmed by the increased time of vacuum tests, raised gingival temperature, reduced tissue clearance, and increased oxygen tension. Apart from that, laser therapy subsided fibrinolysis, proteolytic tissue activity, and decreased the exudative inflammation of periodontium.

  1. Laser Guidance Analysis Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility, which provides for real time, closed loop evaluation of semi-active laser guidance hardware, has and continues to be instrumental in the development...

  2. Airclad fiber laser technology

    DEFF Research Database (Denmark)

    Hansen, Kim P.; Olausson, Christina Bjarnal Thulin; Broeng, Jes

    2008-01-01

    High-power fiber lasers and amplifiers have gained tremendous momentum in the last five years, and many of the traditional manufactures of gas and solid-state lasers are pursuing the attractive fiber-based systems, which are now displacing the old technology in many areas. High-power fiber laser...... systems require specially designed fibers with large cores and good power handling capabilities - requirements that are all met by the airclad fiber technology. In the present paper we go through many of the building blocks needed to build high-power systems and we show an example of a complete airclad...... laser system. We present the latest advancements within airclad fiber technology including a new 70 μm single-mode polarization-maintaining rod-type fiber capable of amplifying to MW power levels. Furthermore we describe the novel airclad based pump combiners and their use in a completely monolithic 350...

  3. Improved Laser Vibration Radar

    National Research Council Canada - National Science Library

    Hilaire, Pierre

    1998-01-01

    .... This thesis reconfigured an existing CO2 laboratory laser radar system that is capable of measuring the frequencies of vibration of a simulated target into a more compact and rugged form for field testing...

  4. Physics of laser plasma

    International Nuclear Information System (INIS)

    Rubenchik, A.; Witkowski, S.

    1991-01-01

    This book provides a comprehensive review of laser fusion plasma physics and contains the most up-to-date information on high density plasma physics and radiation transport, useful for astrophysicists and high density physicists

  5. Fusion reactor pumped laser

    International Nuclear Information System (INIS)

    Jassby, D.L.

    1988-01-01

    A nuclear pumped laser is described comprising: a toroidal fusion reactor, the reactor generating energetic neutrons; an annular gas cell disposed around the outer periphery of the reactor, the cell including an annular reflecting mirror disposed at the bottom of the cell and an annular output window disposed at the top of the cell; a gas lasing medium disposed within the annular cell for generating output laser radiation; neutron reflector material means disposed around the annular cell for reflecting neutrons incident thereon back into the gas cell; neutron moderator material means disposed between the reactor and the gas cell and between the gas cell and the neutron reflector material for moderating the energy of energetic neutrons from the reactor; converting means for converting energy from the moderated neutrons to energy pumping means for pumping the gas lasing medium; and beam compactor means for receiving output laser radiation from the annular output window and generating a single output laser beam therefrom

  6. Compact semiconductor lasers

    CERN Document Server

    Yu, Siyuan; Lourtioz, Jean-Michel

    2014-01-01

    This book brings together in a single volume a unique contribution by the top experts around the world in the field of compact semiconductor lasers to provide a comprehensive description and analysis of the current status as well as future directions in the field of micro- and nano-scale semiconductor lasers. It is organized according to the various forms of micro- or nano-laser cavity configurations with each chapter discussing key technical issues, including semiconductor carrier recombination processes and optical gain dynamics, photonic confinement behavior and output coupling mechanisms, carrier transport considerations relevant to the injection process, and emission mode control. Required reading for those working in and researching the area of semiconductors lasers and micro-electronics.

  7. YAG Laser or bur

    African Journals Online (AJOL)

    2018-02-23

    Feb 23, 2018 ... for the clinical durability of resin-based dental restorations.[1]. Microleakage ... studies evaluating the use of laser systems in primary teeth for cavity ... sealed with glass ionomer restorative material (Fuji. II LC, GC Corporation ...

  8. Foundations of laser spectroscopy

    CERN Document Server

    Stenholm, Stig

    2005-01-01

    A simple presentation of the theoretical foundations of steady-state laser spectroscopy, this text helps students to apply theory to calculations with a systematic series of examples and exercises. 1984 edition.

  9. Thermonuclear fusion by laser

    International Nuclear Information System (INIS)

    Delpech, J.-F.; Fabre, Edouard.

    1978-01-01

    This paper is intended to describe the principle of inetia containment by laser and the research effort undertaken for this purpose. After having enumerated the principal thermonuclear reactions useful for fusion, the authors derive the rhoR criterion that characterizes inertia containment, as well as the Lawson criterion in the case of magnetic containment. The main physics problems involved in inertia containment by laser are enunciated and the article ends with a review of means resorted to in France and abroad for studying this problem. This review also reports C.N.R.S. bustling in this field, within the scope of competence of G.I.L.M. (Groupement de Recherches Coordonnees sur l'Interaction Laser-Matiere = Group for coordinated investigation of matter-laser interaction) established in Paris at the Ecole Polytechnique [fr

  10. DIFFRACTION SYNCHRONIZATION OF LASERS,

    Science.gov (United States)

    semiconductor lasers while suppressing parasitic generation in the plane of the mirror. The diffraction coupling coefficient of open resonators is calculated, and the stability conditions of the synchronized system is determined.

  11. Efficiencies of laser dyes for atomic vapor laser isotope separation

    International Nuclear Information System (INIS)

    Maeda, Mitsuo; Oki, Yuji; Uchiumi, Michihiro; Takao, Takayuki; Igarashi, Kaoru; Shimamoto, Kojiro.

    1995-01-01

    Efficiencies of 30 laser dyes for the atomic vapor laser isotope separation (AVLIS) are experimentally evaluated with a dye laser pumped by a frequency-doubled Nd:YAG laser. On the other hand, a simulation code is developed to describe the laser action of Rhodamine 6G, and the dependence of the laser efficiency on the pump wavelength is calculated. Following conclusions are obtained by these considerations:space: 1) Pyrromethene 567 showed 16% higher laser efficiency than Rhodamine 6G by 532 nm pumping, and Pyrromethene 556 has an ability to provide better efficiency by green light pumping with a Cu vapor laser; 2) Kiton red 620 and Rhodamine 640, whose efficiencies were almost the same as Rhodamine 6G by 532 nm pumping, will show better efficiencies by two-wavelength pumping with a Cu vapor laser. (author)

  12. Future prospects of laser diodes and fiber lasers

    International Nuclear Information System (INIS)

    Ueda, Ken-ichi

    2000-01-01

    For the next century we should develop new concepts for coherent control of light generation and propagation. Owing to the recent development of ultra fine structures in semiconductor lasers, fiber lasers, and various kinds of waveguide structure, we can make optical devices which control the light propagation artificially. But, the phase locking and phase control of multiple laser oscillators are one of the most important directions of laser science and technology. The coherent summation has been a dream of laser since 1960. Is it possible to solve this old and quite challenging problem for laser science? This is also a very basic concept because the laser action based on the stimulated emission is the process of coherent summation of huge number of photons emitted from individual atoms. In this paper, I discuss the fundamental direction of laser research in the next ten or twenty years. The active optics and laser technology should be combined intrinsically in near future. (author)

  13. High-energy molecular lasers self-controlled volume-discharge lasers and applications

    CERN Document Server

    Apollonov, V V

    2016-01-01

    This book displays the physics and design of high-power molecular lasers. The lasers described are self-controlled volume-discharge lasers. The book explains self-sustained discharge lasers, self-initiated discharge lasers and technical approaches to laser design. Important topics discussed are laser efficiency, laser beam quality and electric field homogeneity. The book contains many new innovative applications.

  14. Transurethral vaporesection of prostate: diode laser or thulium laser?

    Science.gov (United States)

    Tan, Xinji; Zhang, Xiaobo; Li, Dongjie; Chen, Xiong; Dai, Yuanqing; Gu, Jie; Chen, Mingquan; Hu, Sheng; Bai, Yao; Ning, Yu

    2018-05-01

    This study compared the safety and effectiveness of the diode laser and thulium laser during prostate transurethral vaporesection for treating benign prostate hyperplasia (BPH). We retrospectively analyzed 205 patients with BPH who underwent a diode laser or thulium laser technique for prostate transurethral vaporesection from June 2016 to June 2017 and who were followed up for 3 months. Baseline characteristics of the patients, perioperative data, postoperative outcomes, and complications were compared. We also assessed the International Prostate Symptom Score (IPSS), quality of life (QoL), maximum flow rate (Q max ), average flow rate (AFR), and postvoid residual volume (PVR) at 1 and 3 months postoperatively to evaluate the functional improvement of each group. There were no significant differences between the diode laser and thulium laser groups related to age, prostate volume, operative time, postoperative hospital stays, hospitalization costs, or perioperative data. The catheterization time was 3.5 ± 0.8 days for the diode laser group and 4.7 ± 1.8 days for the thulium laser group (p diode laser and thulium laser contributes to safe, effective transurethral vaporesection in patients with symptomatic BPH. Diode laser, however, is better than thulium laser for prostate transurethral vaporesection because of its shorter catheterization time. The choice of surgical approach is more important than the choice of laser types during clinical decision making for transurethral laser prostatectomy.

  15. Pulsed chemical laser

    International Nuclear Information System (INIS)

    Jacobson, T.V.; Kimbell, G.H.

    1975-01-01

    A hydrogen fluoride laser capable of operating super radiantly and at atmospheric pressure is described. A transverse electrical discharge is utilized to energize the reaction of a hydrogen donor to provide hydrogen fluoride in a metastable energy state which reverts to a stable state by laser action. A large range of hydrogen and fluorine donors is disclosed. A preferred pair of donors is sulphur hexafluoride and propane. Helium is frequently added to the gas mix to act as a buffer. (U.S.)

  16. Hybrid vertical cavity laser

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper

    2010-01-01

    A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide.......A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide....

  17. Laser Resurfacing Pearls

    OpenAIRE

    Shah, Sonia; Alam, Murad

    2012-01-01

    Ablative skin resurfacing using the carbon dioxide laser was long considered the gold standard for treatment of photoaging, acne scars, and rhytids. However, conventional full-face carbon dioxide resurfacing is associated with significant risk of side effects and a prolonged postoperative recovery period. Fractional resurfacing has recently revolutionized laser surgery by offering close to comparable results with minimal side effects and a more rapid recovery. Although fractional devices have...

  18. Laser cooling of solids

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, Richard I [Los Alamos National Laboratory; Sheik-bahae, Mansoor [UNM

    2008-01-01

    We present an overview of solid-state optical refrigeration also known as laser cooling in solids by fluorescence upconversion. The idea of cooling a solid-state optical material by simply shining a laser beam onto it may sound counter intuitive but is rapidly becoming a promising technology for future cryocooler. We chart the evolution of this science in rare-earth doped solids and semiconductors.

  19. Laser radiation protection

    International Nuclear Information System (INIS)

    Pantelic, D.; Muric, B.; Vasiljevic, D.

    2011-01-01

    We have presented the effects of laser radiation on human organism, with special emphasize on eye as the most sensitive organ. It was pointed-out that there are many parameters that should be taken into account when determining the level of protection from laser light. In that respect it is important to be aware of international standards that regulate this area. In addition, we have described a new material which efficiently protects human eye, by formation of microlens and carbonization. [sr

  20. SHIVA laser: nearing completion

    International Nuclear Information System (INIS)

    Glaze, J.A.; Godwin, R.O.

    1977-01-01

    Construction of the Shiva laser system is nearing completion. This laser will be operating in fall 1977 and will produce over 20 terawatts of focusable power in a subnanosecond pulse. Fusion experiments will begin early in 1978. It is anticipated that thermonuclear energy release equal to one percent that of the incident light energy will be achieved with sub-millimeter deuterium-tritium targets. From other experiments densities in excess of a thousand times that of liquid are also expected

  1. Laser Scanning in Forests

    Directory of Open Access Journals (Sweden)

    Håkan Olsson

    2012-09-01

    Full Text Available The introduction of Airborne Laser Scanning (ALS to forests has been revolutionary during the last decade. This development was facilitated by combining earlier ranging lidar discoveries [1–5], with experience obtained from full-waveform ranging radar [6,7] to new airborne laser scanning systems which had components such as a GNSS receiver (Global Navigation Satellite System, IMU (Inertial Measurement Unit and a scanning mechanism. Since the first commercial ALS in 1994, new ALS-based forest inventory approaches have been reported feasible for operational activities [8–12]. ALS is currently operationally applied for stand level forest inventories, for example, in Nordic countries. In Finland alone, the adoption of ALS for forest data collection has led to an annual savings of around 20 M€/year, and the work is mainly done by companies instead of governmental organizations. In spite of the long implementation times and there being a limited tradition of making changes in the forest sector, laser scanning was commercially and operationally applied after about only one decade of research. When analyzing high-ranked journal papers from ISI Web of Science, the topic of laser scanning of forests has been the driving force for the whole laser scanning research society over the last decade. Thus, the topic “laser scanning in forests” has provided a significant industrial, societal and scientific impact. [...

  2. CO2 laser cutting

    CERN Document Server

    Powell, John

    1998-01-01

    The laser has given manufacturing industry a new tool. When the laser beam is focused it can generate one of the world's most intense energy sources, more intense than flames and arcs, though similar to an electron beam. In fact the intensity is such that it can vaporise most known materials. The laser material processing industry has been growing swiftly as the quality, speed and new manufacturing possibilities become better understood. In the fore of these new technologies is the process of laser cutting. Laser cutting leads because it is a direct process substitu­ tion and the laser can usually do the job with greater flexibility, speed and quality than its competitors. However, to achieve these high speeds with high quality con­ siderable know how and experience is required. This information is usually carefully guarded by the businesses concerned and has to be gained by hard experience and technical understanding. Yet in this book John Powell explains in lucid and almost non­ technical language many o...

  3. Reverse spontaneous laser line sweeping in ytterbium fiber laser

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Petr; Peterka, Pavel; Honzátko, Pavel; Kubeček, V.

    2017-01-01

    Roč. 14, č. 3 (2017), č. článku 035102. ISSN 1612-2011 R&D Projects: GA ČR(CZ) GA16-13306S Institutional support: RVO:67985882 ; RVO:68378271 Keywords : laser line sweeping * ytterbium * fiber lasers Subject RIV: BH - Optics, Masers, Lasers; BH - Optics, Masers, Lasers (FZU-D) OBOR OECD: Optics (including laser optics and quantum optics); Optics (including laser optics and quantum optics) (FZU-D) Impact factor: 2.537, year: 2016

  4. Laser Diode Pumped Solid State Lasers

    Science.gov (United States)

    1987-01-01

    Report N66001-83-C-0071, 17 April 1986, prepared for NOSC. 4.6 W.T. Welford, R. Winston , "The Option of Nonimaging Concentrators ," Academic Press, 1978...by non-imac optics such as reflective or refractive flux concentrators . Simple considerations regarding the optimum pumping configuration, high marks...reduced if the arrays can stand-off from the Nd:YAG laser. As mentioned before, compound parabolic concentrators or refractive optics cat employed to

  5. Greco Laser-matter interaction

    International Nuclear Information System (INIS)

    1986-01-01

    Research program in 1985 at GRECO ILM (Group of Coordinated Research: Interaction Laser Matter) continued with its principal direction in fundamental physics of laser inertial confinement; also researches on X-ray lasers hare been undergone and new high power laser application fields with particle acceleration, material processing and X-ray sources. A six beam laser was operated. Wavelength effects were studied. Atomic physics was deeply stressed as dense medium diagnostics from multicharged ions. Research development in ultra-dense medium was also important X-ray laser research gave outstanding results. New research fields were developed this year: laser acceleration of particles by wave beating or Raman instability; dense laser produced plasma use as X-ray source; material processing by laser shocks [fr

  6. Ultracompact Pseudowedge Plasmonic Lasers and Laser Arrays.

    Science.gov (United States)

    Chou, Yu-Hsun; Hong, Kuo-Bin; Chang, Chun-Tse; Chang, Tsu-Chi; Huang, Zhen-Ting; Cheng, Pi-Ju; Yang, Jhen-Hong; Lin, Meng-Hsien; Lin, Tzy-Rong; Chen, Kuo-Ping; Gwo, Shangjr; Lu, Tien-Chang

    2018-02-14

    Concentrating light at the deep subwavelength scale by utilizing plasmonic effects has been reported in various optoelectronic devices with intriguing phenomena and functionality. Plasmonic waveguides with a planar structure exhibit a two-dimensional degree of freedom for the surface plasmon; the degree of freedom can be further reduced by utilizing metallic nanostructures or nanoparticles for surface plasmon resonance. Reduction leads to different lightwave confinement capabilities, which can be utilized to construct plasmonic nanolaser cavities. However, most theoretical and experimental research efforts have focused on planar surface plasmon polariton (SPP) nanolasers. In this study, we combined nanometallic structures intersecting with ZnO nanowires and realized the first laser emission based on pseudowedge SPP waveguides. Relative to current plasmonic nanolasers, the pseudowedge plasmonic lasers reported in our study exhibit extremely small mode volumes, high group indices, high spontaneous emission factors, and high Purell factors beneficial for the strong interaction between light and matter. Furthermore, we demonstrated that compact plasmonic laser arrays can be constructed, which could benefit integrated plasmonic circuits.

  7. Lasers in endodontics: an overview

    Science.gov (United States)

    Frentzen, Matthias; Braun, Andreas; Koort, Hans J.

    2002-06-01

    The interest in endodontic use of dental laser systems is increasing. Developing laser technology and a better understanding of laser effects widened the spectrum of possible endodontic indications. Various laser systems including excimer-, argon+-, diode-, Nd:YAG-, Er:YAG- and CO2-lasers are used in pulp diagnosis, treatment of hypersensitivity, pulp capping, sterilization of root canals, root canal shaping and obturation or apicoectomy. With the development of new delivery systems - thin and flexible fibers - for many different wavelengths laser applications in endodontics may increase. Since laser devices are still relatively costly, access to them is limited. Most of the clinical applications are laser assisted procedures such as the removing of pulp remnants and debris or disinfection of infected root canals. The essential question is whether a laser can provide improved treatment over conventional care. To perform laser therapy in endodontics today different laser types with adopted wavelengths and pulse widths are needed, each specific to a particular application. Looking into the future we will need endodontic laser equipment providing optimal laser parameters for different treatment modalities. Nevertheless, the quantity of research reports from the last decade promises a genuine future for lasers in endodontics.

  8. Development of frequency tunable Ti:sapphire laser and dye laser pumped by a pulsed Nd:YAG laser

    International Nuclear Information System (INIS)

    Yi, Jong Hoon; Horn, Roland; Wendt, K.

    2001-01-01

    We investigated lasing characteristics of two kinds of tunable laser, liquid dye laser and solid Ti:sapphire crystal laser, pumped by high pulse repetition rate Nd:YAG laser. Dye laser showed drastically reduced pulsewidth compared with that of pump laser and it also contained large amount of amplified spontaneous emission. Ti:sapphire laser showed also reduced pulsewidth. But, the laser conversion pump laser and Ti:sapphire laser pulse, we used a Brewster-cut Pockel's cell for Q-switching. The laser was frequency doubled by a type I BBO crystal outside of the cavity.

  9. Femtosecond Fiber Lasers

    Science.gov (United States)

    Bock, Katherine J.

    This thesis focuses on research I have done on ytterbium-doped femtosecond fiber lasers. These lasers operate in the near infrared region, lasing at 1030 nm. This wavelength is particularly important in biomedical applications, which includes but is not limited to confocal microscopy and ablation for surgical incisions. Furthermore, fiber lasers are advantageous compared to solid state lasers in terms of their cost, form factor, and ease of use. Solid state lasers still dominate the market due to their comparatively high energy pulses. High energy pulse generation in fiber lasers is hindered by either optical wave breaking or by multipulsing. One of the main challenges for fiber lasers is to overcome these limitations to achieve high energy pulses. The motivation for the work done in this thesis is increasing the output pulse peak power and energy. The main idea of the work is that decreasing the nonlinearity that acts on the pulse inside the cavity will prevent optical wave breaking, and thus will generate higher energy pulses. By increasing the output energy, ytterbium-doped femtosecond fiber lasers can be competitive with solid state lasers which are used commonly in research. Although fiber lasers tend to lack the wavelength tuning ability of solid state lasers, many biomedical applications take advantage of the 1030 microm central wavelength of ytterbium-doped fiber lasers, so the major limiting factor of fiber lasers in this field is simply the output power. By increasing the output energy without resorting to external amplification, the cavity is optimized and cost can remain low and economical. During verification of the main idea, the cavity was examined for possible back-reflections and for components with narrow spectral bandwidths which may have contributed to the presence of multipulsing. Distinct cases of multipulsing, bound pulse and harmonic mode-locking, were observed and recorded as they may be of more interest in the future. The third

  10. Lasers '90: Proceedings of the 13th International Conference on Lasers and Applications, San Diego, CA, Dec. 10-14, 1990

    International Nuclear Information System (INIS)

    Harris, D.G.; Herbelin, J.

    1991-01-01

    The general topics considered are: x-ray lasers; FELs; solid state lasers; techniques and phenomena of ultrafast lasers; optical filters and free space laser communications; discharge lasers; tunable lasers; applications of lasers in medicine and surgery; lasers in materials processing; high power lasers; dynamics gratings, wave mixing, and holography; up-conversion lasers; lidar and laser radar; laser resonators; excimer lasers; laser propagation; nonlinear and quantum optics; blue-green technology; imaging; laser spectroscopy; chemical lasers; dye lasers; and lasers in chemistry

  11. High power ultrashort pulse lasers

    International Nuclear Information System (INIS)

    Perry, M.D.

    1994-01-01

    Small scale terawatt and soon even petawatt (1000 terawatt) class laser systems are made possible by application of the chirped-pulse amplification technique to solid-state lasers combined with the availability of broad bandwidth materials. These lasers make possible a new class of high gradient accelerators based on the large electric fields associated with intense laser-plasma interactions or from the intense laser field directly. Here, we concentrate on the laser technology to produce these intense pulses. Application of the smallest of these systems to the production of high brightness electron sources is also introduced

  12. Injection-controlled laser resonator

    Science.gov (United States)

    Chang, J.J.

    1995-07-18

    A new injection-controlled laser resonator incorporates self-filtering and self-imaging characteristics with an efficient injection scheme. A low-divergence laser signal is injected into the resonator, which enables the injection signal to be converted to the desired resonator modes before the main laser pulse starts. This injection technique and resonator design enable the laser cavity to improve the quality of the injection signal through self-filtering before the main laser pulse starts. The self-imaging property of the present resonator reduces the cavity induced diffraction effects and, in turn, improves the laser beam quality. 5 figs.

  13. Laser safety in the lab

    CERN Document Server

    Barat, Ken L

    2012-01-01

    There is no more challenging setting for laser use than a research environment. In almost every other setting the laser controls count on engineering controls, and human exposure is kept to a minimum. In research, however, the user often manipulates the optical layout and thereby places him or herself in peril, but this does not mean that accidents and injury are unavoidable. On the contrary, laser accidents can be avoided by following a number of simple approaches. [i]Laser Safety in the Lab[/i] provides the laser user and laser safety officer with practical guidelines from housekeeping to ey

  14. NTES laser facility for physics experiments

    International Nuclear Information System (INIS)

    Christie, D.J.; Foley, R.J.; Frank, D.N.

    1989-01-01

    This paper discusses the following topics on the NTES laser facility: Mission Statement and Project Description; Experiment Area; High-Energy, Double-Pass Laser; Facilities; Laser Control and Data Acquisition; and Auxiliary Lasers

  15. Theoretical studies of solar-pumped lasers

    Science.gov (United States)

    Harries, W. L.

    1983-01-01

    Possible types of lasers were surveyed for solar power conversion. The types considered were (1) liquid dye lasers, (2) vapor dye lasers, and (3) nondissociative molecular lasers. These are discussed.

  16. Laser-based additive manufacturing of metals

    CSIR Research Space (South Africa)

    Kumar, S

    2010-11-01

    Full Text Available For making metallic products through Additive Manufacturing (AM) processes, laser-based systems play very significant roles. Laser-based processes such as Selective Laser Melting (SLM) and Laser Engineered Net Shaping (LENS) are dominating processes...

  17. Ultrashort pulse laser technology laser sources and applications

    CERN Document Server

    Schrempel, Frank; Dausinger, Friedrich

    2016-01-01

    Ultrashort laser pulses with durations in the femtosecond range up to a few picoseconds provide a unique method for precise materials processing or medical applications. Paired with the recent developments in ultrashort pulse lasers, this technology is finding its way into various application fields. The book gives a comprehensive overview of the principles and applications of ultrashort pulse lasers, especially applied to medicine and production technology. Recent advances in laser technology are discussed in detail. This covers the development of reliable and cheap low power laser sources as well as high average power ultrashort pulse lasers for large scale manufacturing. The fundamentals of laser-matter-interaction as well as processing strategies and the required system technology are discussed for these laser sources with respect to precise materials processing. Finally, different applications within medicine, measurement technology or materials processing are highlighted.

  18. Transcanalicular laser dacryocystorhinostomy using low energy 810 nm diode laser

    Directory of Open Access Journals (Sweden)

    Sanjiv K Gupta

    2012-01-01

    Conclusions: Transcanalicular Laser DCR can be safely performed using a low power 810 nm diode laser. The surgery is elegant, minimally invasive, allows fast rehabilitation, and has an excellent success rate.

  19. Laser spectroscopy and laser isotope separation of atomic gadolinium

    International Nuclear Information System (INIS)

    Chen, Y. W.; Yamanaka, C.; Nomaru, K.; Kou, K.; Niki, H.; Izawa, Y.; Nakai, S.

    1994-01-01

    Atomic vapor laser isotope separation (AVLIS) is a process which uses intense pulsed lasers to selectively photoionize one isotopic species of a chemical element, after which these ions are extracted electromagnetically. The AVLIS has several advantages over the traditional methods based on the mass difference, such as high selectivity, low energy consumption, short starting time and versatility to any atoms. The efforts for atomic vapor laser isotope separation at ILT and ILE, Osaka University have been concentrated into the following items: 1) studies on laser spectroscopy and laser isotope separation of atomic gadolinium, 2) studies on interaction processes including coherent dynamics, propagation effects and atom-ion collision in AVLIS system, 3) development of laser systems for AVLIS. In this paper, we present experimental results on the laser spectroscopy and laser isotope separation of atomic gadolinium.

  20. Laser marking method and device

    International Nuclear Information System (INIS)

    Okazaki, Yuki; Aoki, Nobutada; Mukai, Narihiko; Sano, Yuji; Yamamoto, Seiji.

    1997-01-01

    An object is disposed in laser beam permeating liquid or gaseous medium. Laser beams such as CW laser or pulse laser oscillated from a laser device are emitted to the object to apply laser markings with less degradation of identification and excellent corrosion resistance on the surface of the object simply and easily. Upon applying the laser markings, a liquid or gas as a laser beam permeating medium is blown onto the surface of the object, or the liquid or gas in the vicinity of the object is sucked, the laser beam-irradiated portion on the surface can be cooled positively. Accordingly, the laser marking can be formed on the surface of the object with less heat affection to the object. In addition, if the content of a nitrogen gas in the laser beam permeating liquid medium is reduced by degassing to lower than a predetermined value, or the laser beam permeating gaseous medium is formed by an inert gas, a laser marking having high corrosion resistance and reliability can be formed on the surface of the objective member. (N.H.)

  1. Proceedings of national laser symposium (NLS-2000)

    International Nuclear Information System (INIS)

    Mallik, Amitav; Srivastava, K.N.; Pal, Suranjan

    2000-01-01

    This proceedings comprise of a series of invited talks on selected topics in lasers and wide range of contributed papers. The main topics are laser physics and research, laser devices and technology, laser materials and spectroscopy, quantum optics, non-linear optics ultra-fast phenomenon, laser produced plasma, high power lasers, laser instrumentation, medical applications and industrial applications of lasers and fiber optics. The papers relevant to INIS Database are indexed separately

  2. Laser tissue interactions: an update for otolaryngology

    Science.gov (United States)

    Reinisch, Lou

    2000-05-01

    We review the laser, characteristics of laser light, the delivery of laser light, pulse lengths and laser tissue interactions. We review these parameters and how they have changed over the history of the laser and how we expect them to change in the future. This survey of laser use is targeted to the otolaryngologist. Very little background in lasers is necessary to follow the discussion. This is intended to introduce and reintroduce laser technology.

  3. Photonic Molecule Lasers Revisited

    Science.gov (United States)

    Gagnon, Denis; Dumont, Joey; Déziel, Jean-Luc; Dubé, Louis J.

    2014-05-01

    Photonic molecules (PMs) formed by coupling two or more optical resonators are ideal candidates for the fabrication of integrated microlasers, photonic molecule lasers. Whereas most calculations on PM lasers have been based on cold-cavity (passive) modes, i.e. quasi-bound states, a recently formulated steady-state ab initio laser theory (SALT) offers the possibility to take into account the spectral properties of the underlying gain transition, its position and linewidth, as well as incorporating an arbitrary pump profile. We will combine two theoretical approaches to characterize the lasing properties of PM lasers: for two-dimensional systems, the generalized Lorenz-Mie theory will obtain the resonant modes of the coupled molecules in an active medium described by SALT. Not only is then the theoretical description more complete, the use of an active medium provides additional parameters to control, engineer and harness the lasing properties of PM lasers for ultra-low threshold and directional single-mode emission. We will extend our recent study and present new results for a number of promising geometries. The authors acknowledge financial support from NSERC (Canada) and the CERC in Photonic Innovations of Y. Messaddeq.

  4. HF-laser program

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Sandia's HF-laser program for FY 77 and FY 78 was revised in June 1977 in order to meet several new program milestones. Research progress is reported on: objective of HF oscillator-amplifier studies using H 2 -F 2 gas mixtures; characteristics of large-volume oscillator using H 2 -F 2 mixtures; characteristics of large-volume amplifier using H 2 -F 2 mixtures; experimental results of the oscillator-amplifier study; objective of high-quality discharge-initiated SF 6 -HI oscillator-preamplifier system; pin-discharge-initiated oscillator and first beam expander; fast-discharge-initiated preamplifiers; reflecting beam expanders for oscillator-preamplifier system; beam quality of discharge-initiated oscillator-preamplifier system; short pulse option for discharge initiated SF 6 -HI system; H 2 -F 2 electron-beam-initiated oscillator-preamplifier system; chamber for HF-laser focusing experiments; computer study of parasitic oscillations in HF amplifiers and oscillators; kinetics upgrade of HF-laser code; repetitivey ignited flowing H 2 -F 2 -O 2 mixtures; spontaneous detonations in multiatmosphere H 2 -F 2 -O 2 mixtures; high-pressure H 2 -F 2 laser studies; and time sequenced energy extraction on the high xenon laser

  5. Pulsed inductive HF laser

    Energy Technology Data Exchange (ETDEWEB)

    Razhev, A M; Kargapol' tsev, E S [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Churkin, D S; Demchuk, S V [Novosibirsk State University, Novosibirsk (Russian Federation)

    2016-03-31

    We report the results of experimentally investigated dependences of temporal, spectral and spatial characteristics of an inductive HF-laser generation on the pump conditions. Gas mixtures H{sub 2} – F{sub 2}(NF{sub 3} or SF6{sub 6}) and He(Ne) – H{sub 2} – F{sub 2}(NF{sub 3} or SF{sub 6}) were used as active media. The FWHM pulse duration reached 0.42 μs. This value corresponded to a pulsed power of 45 kW. For the first time, the emission spectrum of an inductive HF laser was investigated, which consisted of seven groups of bands with centres around the wavelengths of 2732, 2736, 2739, 2835, 2837, 2893 and 2913 nm. The cross section profile of the laser beam was a ring with a diameter of about 20 mm and width of about 5 mm. Parameters of laser operation in the repetitively pulsed regime were sufficiently stable. The amplitude instability of light pulses was no greater than 5% – 6%. (lasers)

  6. Industrial lasers in Japan

    Science.gov (United States)

    Karube, Norio

    1991-03-01

    I am to report on some aspects of industrial lasers in Japan. Mostly centering on the market. In Japan, the history of laser developnent is rather profound. And long. Ever since the first invention of the laser in this country in 1960. This is partly because of the fact that in Japan the spectroscopic studies of the ruby was very popular in the late 1950's. Ever since niost of the work has been done in the research laboratories of the industry, not in the universities or not in the governmental laboratories. And since that time our first activity was mainly centering on the basic research, but after that time we have the evolution of the technology. One of the features in Japan is that the activity of developement and research of laser technology from the very basic phase up to the present commercialization has been done by the same group of people, including ine. We had a national project which ended about six years ago which was sponsored by MITI. MITI is Ministry of International Trade and Industry in Japan. And because of this national project, the effect of this project had a very enlightening effect in Japan. And after that our Japanese laser market became very flourishing.

  7. Laser power sources and laser technology for accelerators

    International Nuclear Information System (INIS)

    Lowenthal, D.

    1986-01-01

    The requirements on laser power sources for advanced accelerator concepts are formidable. These requirements are driven by the need to deliver 5 TeV particles at luminosities of 10/sup 33/ - 10/sup 34/ cm/sup -2/ sec/sup -1/. Given that optical power can be transferred efficiently to the particles these accelerator parameters translate into single pulse laser output energies of several kilojoules and rep rates of 1-10 kHz. The average laser output power is then 10-20 MW. Larger average powers will be needed if efficient transfer proves not to be possible. A laser plant of this magnitude underscores the importance of high wall plug efficiency and reasonable cost in $/Watt. The interface between the laser output pulse format and the accelerator structure is another area that drives the laser requirements. Laser accelerators break up into two general architectures depending on the strength of the laser coupling. For strong coupling mechanisms, the architecture requires many ''small'' lasers powering the accelerator in a staged arrangement. For the weak coupling mechanisms, the architecture must feature a single large laser system whose power must be transported along the entire accelerator length. Both of these arrangements have demanding optical constraints in terms of phase matching sequential stages, beam combining arrays of laser outputs and optimizing coupling of laser power in a single accelerating stage

  8. Laser Ablation of Biological Tissue Using Pulsed CO2 Laser

    International Nuclear Information System (INIS)

    Hashishin, Yuichi; Sano, Shu; Nakayama, Takeyoshi

    2010-01-01

    Laser scalpels are currently used as a form of laser treatment. However, their ablation mechanism has not been clarified because laser excision of biological tissue occurs over a short time scale. Biological tissue ablation generates sound (laser-induced sound). This study seeks to clarify the ablation mechanism. The state of the gelatin ablation was determined using a high-speed video camera and the power reduction of a He-Ne laser beam. The aim of this study was to clarify the laser ablation mechanism by observing laser excision using the high-speed video camera and monitoring the power reduction of the He-Ne laser beam. We simulated laser excision of a biological tissue by irradiating gelatin (10 wt%) with radiation from a pulsed CO 2 laser (wavelength: 10.6 μm; pulse width: 80 ns). In addition, a microphone was used to measure the laser-induced sound. The first pulse caused ablation particles to be emitted in all directions; these particles were subsequently damped so that they formed a mushroom cloud. Furthermore, water was initially evaporated by laser irradiation and then tissue was ejected.

  9. Lasers in atomic, molecular and nuclear physics

    International Nuclear Information System (INIS)

    Letokhov, V.S.

    1986-01-01

    This book presents papers on laser applications in atomic, molecular and nuclear physics. Specifically discussed are: laser isotope separation; laser spectroscopy of chlorophyll; laser spectroscopy of molecules and cell membranes; laser detection of atom-molecule collisions and lasers in astrophysics

  10. The application of laser plasma in ophthalmology

    International Nuclear Information System (INIS)

    He Yujiang; Luo Le; Sun Yabing

    2000-01-01

    The production and development of laser plasma are introduced, and the contribution of laser biomedicine and laser plasma technology to ophthalmology is analyzed. The latest three progresses (laser photocoagulation, photo-refractive keratotomy and laser iridectomy) of laser plasma applications in ophthalmology are presented

  11. Novel plasmon nano-lasers

    NARCIS (Netherlands)

    Hill, M.T.; Marell, M.J.H.

    2010-01-01

    We will discuss some of the latest developments in metallic and plasmonic nano-lasers. Furthermore we will present our latest results on further miniaturization of electrically pumped plasmonic nano-lasers and also DFB Plasmon mode devices.

  12. Coupled optical resonance laser locking.

    Science.gov (United States)

    Burd, S C; du Toit, P J W; Uys, H

    2014-10-20

    We have demonstrated simultaneous laser frequency stabilization of a UV and IR laser, to coupled transitions of ions in the same spectroscopic sample, by detecting only the absorption of the UV laser. Separate signals for locking the different lasers are obtained by modulating each laser at a different frequency and using lock-in detection of a single photodiode signal. Experimentally, we simultaneously lock a 369 nm and a 935 nm laser to the (2)S(1/2) → (2)(P(1/2) and (2)D(3/2) → (3)D([3/2]1/2) transitions, respectively, of Yb(+) ions generated in a hollow cathode discharge lamp. Stabilized lasers at these frequencies are required for cooling and trapping Yb(+) ions, used in quantum information and in high precision metrology experiments. This technique should be readily applicable to other ion and neutral atom systems requiring multiple stabilized lasers.

  13. Laser cladding of turbine blades

    International Nuclear Information System (INIS)

    Shepeleva, L.; Medres, B.; Kaplan, W.D.; Bamberger, M.

    2000-01-01

    A comparative study of two different techniques for the application of wear-resistant coatings for contact surfaces of shroud shelves of gas turbine engine blades (GTE) has been conducted. Wear-resistant coatings were applied on In713 by laser cladding with direct injection of the cladding powder into the melt pool. Laser cladding was conducted with a TRUMPF-2500, CW-CO 2 laser. The laser cladding was compared with commercially available plasma cladding with wire. Both plasma and laser cladded zones were characterized by optical and scanning electron microscopy. It was found that the laser cladded zone has a higher microhardness value (650-820 HV) compared with that of the plasma treated material (420-440 HV). This is a result of the significant reduction in grain size in the case of laser cladding. Unlike the plasma cladded zones, the laser treated material is free of micropores and microcracks. (orig.)

  14. Nano lasers in photonic VLSI

    NARCIS (Netherlands)

    Hill, M.T.; Oei, Y.S.; Smit, M.K.

    2007-01-01

    We examine the use of micro and nano lasers to form digital photonic VLSI building blocks. Problems such as isolation and cascading of building blocks are addressed, and the potential of future nano lasers explored.

  15. Laser sources for object illumination

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, G.F. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The considerations which formulate the specifications for a laser illuminator are explained, using the example of an underwater object. Depending on the parameters which define the scenario, widely varying laser requirements result.

  16. Polarisation effects in fibre lasers

    OpenAIRE

    Lin, J.T.; Morkel, P.R.; Reekie, L.; Payne, D.N.

    1987-01-01

    Two orthogonal polarisation eigenmodes have been observed in a single-mode fibre laser. Experimental investigation shows good agreement with theoretical analysis. Both Nd3+ and Er3+-doped single-polarisation single-mode fibre lasers have been demonstrated

  17. Flashlamp excited fluid laser amplified

    International Nuclear Information System (INIS)

    1976-01-01

    The patent describes a laser amplifier with chambers for containing and amplifying an intensifier medium. It serves the need for a large impulse repetition rate and high intensities as required e.g. for laser isotope separation

  18. XeBr exciplex laser

    International Nuclear Information System (INIS)

    Searles, S.K.

    1976-01-01

    Laser emission from the recently discovered XeBr exciplex laser was investigated as a function of the partial pressures of Xe and Br 2 . An optical loss process appears to limit high-pressure operation

  19. Polymer laser bio-sensors

    DEFF Research Database (Denmark)

    Kristensen, Anders; Vannahme, Christoph; Hermannsson, Pétur Gordon

    2014-01-01

    Organic dye based distributed feed-back lasers, featuring narrow linewidth and thus high quality spectral resolution, are used as highly sensitive refractive index sensors. The design, fabrication and application of the laser intra-cavity sensors are discussed....

  20. Laser Diagnostics for Reacting Flows

    National Research Council Canada - National Science Library

    Hanson, Ronald K

    2007-01-01

    ... (UV) or infrared (IR) wavelengths. The cw lasers were spectrally narrow, allowing study of innovative diagnostics based on spectral lineshapes, while the pulsed lasers provided intense bursts of photons needed for techniques based on LIF...

  1. Primer on laser scattering diagnostics

    International Nuclear Information System (INIS)

    Jahoda, F.C.

    1978-07-01

    The theory of laser scattering is presented in abbreviated format, with emphasis on physical interpretation, followed by sections on laser sources, practical considerations in designing experiments, and current developments in extending the techniques to multispace and multitime point measurements

  2. Possibilities of rotary ultrasonic machining in order to give a boost to technical ceramics in the actual Spanish market; Posibilidades del mecanizado por ultrasonidos rotatorio para fomentar el uso de las ceramicas tecnicas en el mercado Espanol actual

    Energy Technology Data Exchange (ETDEWEB)

    Arriola, I.; Gonzalo, O.; Bengoetxea, I.

    2012-11-01

    The advanced properties of engineering ceramics are suitable to meet the requirements of several engineering applications such as medical (prosthesis), automotive (bearing...), aerospace (tiles,...), optics (lasers,) and so on, where high hardness, high wear resistance and thermo chemical stability are needed. However, the processing of these materials is difficult and costly, in some cases up to 90% of the price, which leads ceramics to limited applications. Rotary Ultrasonic Machining (RUM) is presented as a non conventional environmental-friendly and cost effective process that enables to obtain complex 3D shape ceramic products. A rotating tool with metal-bonded diamond abrasives is ultrasonically vibrated (typically 20KHz) and fed toward to the fixed work piece at a constant pressure or a constant feed rate This process combines conventional grinding and ultrasonic machining, offering the possibility of increased material removal rates while keeping the machining forces low. Thus, the limitations of actually used conventional processes are overcome introducing more accurate, flexible and cost effective process capabilities. On balance, RUM is a promising process for primary machining operations on structural ceramic components. Its features will lead to enhance the use of ceramics in more industrial applications by increasing product development/design capabilities, high added value products and sustainable process. (Author) 43 refs.

  3. Femtosecond laser spectroscopy

    CERN Document Server

    Hannaford, Peter

    2005-01-01

    As concepts and methodologies have evolved over the past two decades, the realm of ultrafast science has become vast and exciting and has impacted many areas of chemistry, biology and physics, and other fields such as materials science, electrical engineering, and optical communication. The field has recently exploded with the announcement of a series of remarkable new developments and advances. This volume surveys this recent growth in eleven chapters written by leading international researchers in the field. It includes sections on femtosecond optical frequency combs, soft x-ray femtosecond laser sources, and attosecond laser sources. In addition, the contributors address real-time spectroscopy of molecular vibrations with sub-5-fs pulses and multidimensional femtosecond coherent spectroscopies for studying molecular and electron dynamics. Novel methods for measuring and characterizing ultrashort laser pulses and ultrashort pulses of light are also described. The topics covered are revolutionizing the field...

  4. Laser facilitates vaccination

    Directory of Open Access Journals (Sweden)

    Ji Wang

    2016-01-01

    Full Text Available Development of novel vaccine deliveries and vaccine adjuvants is of great importance to address the dilemma that the vaccine field faces: to improve vaccine efficacy without compromising safety. Harnessing the specific effects of laser on biological systems, a number of novel concepts have been proposed and proved in recent years to facilitate vaccination in a safer and more efficient way. The key advantage of using laser technology in vaccine delivery and adjuvantation is that all processes are initiated by physical effects with no foreign chemicals administered into the body. Here, we review the recent advances in using laser technology to facilitate vaccine delivery and augment vaccine efficacy as well as the underlying mechanisms.

  5. Fundamentals of semiconductor lasers

    CERN Document Server

    Numai, Takahiro

    2015-01-01

    This book explains physics under the operating principles of semiconductor lasers in detail based on the experience of the author, dealing with the first manufacturing of phase-shifted DFB-LDs and recent research on transverse modes.   The book also bridges a wide gap between journal papers and textbooks, requiring only an undergraduate-level knowledge of electromagnetism and quantum mechanics, and helps readers to understand journal papers where definitions of some technical terms vary, depending on the paper. Two definitions of the photon density in the rate equations and two definitions of the phase-shift in the phase-shifted DFB-LD are explained, and differences in the calculated results are indicated, depending on the definitions.    Readers can understand the physics of semiconductor lasers and analytical tools for Fabry-Perot LDs, DFB-LDs, and VCSELs and will be stimulated to develop semiconductor lasers themselves.

  6. Excimer laser technology

    International Nuclear Information System (INIS)

    Mace, P.N.

    1980-01-01

    Scaling presently available excimer laser systems to lasers designed to operate at high average power and high pulse repetition rates for long periods of time requires advances in many areas of engineering technology. For economical application to industrial processes, the efficiency must be increased. This leads to more stringent requirements on preionization techniques, energy delivery systems, and system chemistry. Long life operation (> 10 9 to 10 10 pulses) requires development of new pulse power components, optical elements and flow system components. A broad-based program underway at the Los Alamos Scientific Laboratory is addressing these key technology issues, with the help of advanced component and systems development programs in industry. A prototype XeCl laser meeting all requirements for efficiency, system performance and life is scheduled for completion in 1984

  7. Laser cooling at resonance

    Science.gov (United States)

    Yudkin, Yaakov; Khaykovich, Lev

    2018-05-01

    We show experimentally that three-dimensional laser cooling of lithium atoms on the D2 line is possible when the laser light is tuned exactly to resonance with the dominant atomic transition. Qualitatively, it can be understood by applying simple Doppler cooling arguments to the specific hyperfine structure of the excited state of lithium atoms, which is both dense and inverted. However, to build a quantitative theory, we must resolve to a full model which takes into account both the entire atomic structure of all 24 Zeeman sublevels and the laser light polarization. Moreover, by means of Monte Carlo simulations, we show that coherent processes play an important role in showing consistency between the theory and the experimental results.

  8. Antares laser power amplifier

    International Nuclear Information System (INIS)

    Stine, R.D.; Ross, G.F.; Silvernail, C.

    1979-01-01

    The overall design of the Antares laser power amplifier is discussed. The power amplifier is the last stage of amplification in the 100-kJ Antares laser. In the power amplifier a single, cylindrical, grid-controlle, cold-cathode electron gun is surrounded by 12 large-aperture CO 2 electron-beam sustained laser discharge sectors. Each power amplifier will deliver 18 kJ and the six modules used in Antares will produce the required 100 kJ for delivery to the target. A large-scale interaction between optical, mechanical, and electrical disciplines is required to meet the design objectives. Significant component advances required by the power amplifier design are discussed

  9. Integrated Broadband Quantum Cascade Laser

    Science.gov (United States)

    Mansour, Kamjou (Inventor); Soibel, Alexander (Inventor)

    2016-01-01

    A broadband, integrated quantum cascade laser is disclosed, comprising ridge waveguide quantum cascade lasers formed by applying standard semiconductor process techniques to a monolithic structure of alternating layers of claddings and active region layers. The resulting ridge waveguide quantum cascade lasers may be individually controlled by independent voltage potentials, resulting in control of the overall spectrum of the integrated quantum cascade laser source. Other embodiments are described and claimed.

  10. Broad band exciplex dye lasers

    International Nuclear Information System (INIS)

    Dienes, A.; Shank, C.V.; Trozzolo, A.M.

    1975-01-01

    The disclosure is concerned with exciplex dye lasers, i.e., lasers in which the emitting species is a complex formed only from a constituent in an electronically excited state. Noting that an exciplex laser, favorable from the standpoint of broad tunability, results from a broad shift in the peak emission wavelength for the exciplex relative to the unreacted species, a desirable class resulting in such broad shift is described. Preferred classes of laser media utilizing specified resonant molecules are set forth. (auth)

  11. Study on laser atomic spectroscopy

    International Nuclear Information System (INIS)

    Lee, Jong Min; Song, Kyu Seok; Jeong, Do Young; Kim, Chul Joong; Han, Phil Soon

    1992-01-01

    Electric discharge type atomic vaporizer is developed for the spectroscopic study on actinide elements. Laser induced fluorescence study on actinide elements is performed by using this high temperature type atomizer. For the effective photoionization of elements, copper vapor laser pumped dye laser and electron beam heating type atomic vaporizer are built and their characteristics are measured. In addition, resonance ionization mass spectroscopic analysis for lead sample as well as laser induced fluorescence study on uranium sample in solution phase is made. (Author)

  12. Lasers probe the atomic nucleus

    International Nuclear Information System (INIS)

    Eastham, D.

    1986-01-01

    The article is contained in a booklet on the Revised Nuffield Advanced Physics Course, and concentrates on two techniques to illustrate how lasers probe the atomic nucleus. Both techniques employ resonance fluorescence spectroscopy for obtaining atomic transition energies. The first uses lasers to determine the change in the nuclear charge radius with isotope, the second concerns the use of lasers for ultrasensitive detection of isotopes and elements. The application of lasers in resonance ionization spectroscopy and proton decay is also described. (UK)

  13. Parameters in fractional laser assisted delivery of topical anesthetics: Role of laser type and laser settings.

    Science.gov (United States)

    Meesters, Arne A; Nieboer, Marilin J; Kezic, Sanja; de Rie, Menno A; Wolkerstorfer, Albert

    2018-05-07

    Efficacy of topical anesthetics can be enhanced by pretreatment of the skin with ablative fractional lasers. However, little is known about the role of parameters such as laser modality and laser density settings in this technique. Aims of this study were to compare the efficacy of pretreatment with two different ablative fractional laser modalities, a CO 2 laser and an Er:YAG laser, and to assess the role of laser density in ablative fractional laser assisted topical anesthesia. In each of 15 healthy subjects, four 10 × 10 mm test regions on the back were randomized to pretreatment (70-75 μm ablation depth) with CO 2 laser at 5% density, CO 2 laser at 15% density, Er:YAG laser at 5% density or Er:YAG laser at 15% density. Articaine hydrochloride 40 mg/ml + epinephrine 10 μg/ml solution was applied under occlusion to all four test regions. After 15 minutes, a pass with the CO 2 laser (1,500 μm ablation depth) was administered as pain stimulus to each test region. A reference pain stimulus was given on unanesthetized skin. The main outcome parameter, pain, was scored on a 0-10 visual analogue scale (VAS) after each pain stimulus. Median VAS scores were 1.50 [CO 2 5%], 0.50 [CO 2 15%], 1.50 [Er:YAG 5%], 0.43 [Er:YAG 15%], and 4.50 [unanesthetized reference]. VAS scores for all pretreated test regions were significantly lower compared to the untreated reference region (P laser pretreated regions. However, VAS scores were significantly lower at 15% density compared to 5% density for both for the CO 2 laser (P laser (P laser was considered slightly more painful than pretreatment with Er:YAG laser by the subjects. Fractional laser assisted topical anesthesia is effective even with very low energy settings and an occlusion time of only 15 minutes. Both the CO 2 laser and the Er:YAG laser can be used to assist topical anesthesia although the CO 2 laser pretreatment is experienced as more painful. In our study settings, using articaine

  14. Laser vaccine adjuvants

    Science.gov (United States)

    Kashiwagi, Satoshi; Brauns, Timothy; Gelfand, Jeffrey; Poznansky, Mark C

    2014-01-01

    Immunologic adjuvants are essential for current vaccines to maximize their efficacy. Unfortunately, few have been found to be sufficiently effective and safe for regulatory authorities to permit their use in vaccines for humans and none have been approved for use with intradermal vaccines. The development of new adjuvants with the potential to be both efficacious and safe constitutes a significant need in modern vaccine practice. The use of non-damaging laser light represents a markedly different approach to enhancing immune responses to a vaccine antigen, particularly with intradermal vaccination. This approach, which was initially explored in Russia and further developed in the US, appears to significantly improve responses to both prophylactic and therapeutic vaccines administered to the laser-exposed tissue, particularly the skin. Although different types of lasers have been used for this purpose and the precise molecular mechanism(s) of action remain unknown, several approaches appear to modulate dendritic cell trafficking and/or activation at the irradiation site via the release of specific signaling molecules from epithelial cells. The most recent study, performed by the authors of this review, utilized a continuous wave near-infrared laser that may open the path for the development of a safe, effective, low-cost, simple-to-use laser vaccine adjuvant that could be used in lieu of conventional adjuvants, particularly with intradermal vaccines. In this review, we summarize the initial Russian studies that have given rise to this approach and comment upon recent advances in the use of non-tissue damaging lasers as novel physical adjuvants for vaccines. PMID:25424797

  15. Diode laser pumping

    International Nuclear Information System (INIS)

    Skagerlund, L.E.

    1975-01-01

    A diode laser is pumped or pulsed by a repeated capacitive discharge. A capacitor is periodically charged from a dc voltage source via a transformer, the capacitor being discharged through the diode laser via a controlled switching means after one or more charging periods. During a first interval of each charging period the transformer, while unloaded, stores a specific amount of energy supplied from the dc voltage source. During a subsequent interval of the charging period said specific amount of energy is transmitted from the transformer to the capacitor. The discharging of the capacitor takes place during a first interval of a charging period. (auth)

  16. Power Play, Laser Style

    Science.gov (United States)

    1998-01-01

    Under a NASA SBIR (Small Business Innovation Research) SDL, Inc., has developed the TC40 Single-Frequency Continuously Tunable 500 mw Laser Diode System. This is the first commercially available single frequency diode laser system that offers the broad tunability and the high powers needed for atomic cooling and trapping as well as a variety of atomic spectroscopy techniques. By greatly decreasing both the equipment and the costs of entry, the TC40 enables researchers to pursue some of the most interesting areas of physical chemistry, biochemistry, and atomic physics.

  17. Optics, light and lasers

    CERN Document Server

    Meschede, Dieter

    2008-01-01

    Starting from the concepts of classical optics, Optics, Light and Lasers introduces in detail the phenomena of linear and nonlinear light matter interaction, the properties of modern laser sources, and the concepts of quantum optics. Several examples taken from the scope of modern research are provided to emphasize the relevance of optics in current developments within science and technology. The text has been written for newcomers to the topic and benefits from the author's ability to explain difficult sequences and effects in a straightforward and easily comprehensible way. To this second, c

  18. Mode selection laser

    DEFF Research Database (Denmark)

    2014-01-01

    spatial reflector variations, may be combined to generate a laser beam containing a plurality of orthogonal modes. The laser beam may be injected into a few- mode optical fiber, e.g. for the purpose of optical communication. The VCSEL may have intra-cavity contacts (31,37) and a Tunnel junction (33......) for current confinement into the active layer (34). An air-gap layer (102) may be provided between the upper reflector (15) and the SOI wafer (50) acting as a substrate. The lower reflector may be designed as a high-contrast grating (51) by etching....

  19. Traveling wave laser system

    International Nuclear Information System (INIS)

    Gregg, D.W.; Kidder, R.E.; Biehl, A.T.

    1975-01-01

    The invention broadly involves a method and means for generating a traveling wave laser pulse and is basically analogous to a single pass light amplifier system. However, the invention provides a traveling wave laser pulse of almost unlimited energy content, wherein a gain medium is pumped in a traveling wave mode, the traveling wave moving at essentially the velocity of light to generate an amplifying region or zone which moves through the medium at the velocity of light in the presence of directed stimulating radiation, thereby generating a traveling coherent, directed radiation pulse moving with the amplification zone through the gain medium. (U.S.)

  20. Laser pulse stacking method

    Science.gov (United States)

    Moses, E.I.

    1992-12-01

    A laser pulse stacking method is disclosed. A problem with the prior art has been the generation of a series of laser beam pulses where the outer and inner regions of the beams are generated so as to form radially non-synchronous pulses. Such pulses thus have a non-uniform cross-sectional area with respect to the outer and inner edges of the pulses. The present invention provides a solution by combining the temporally non-uniform pulses in a stacking effect to thus provide a more uniform temporal synchronism over the beam diameter. 2 figs.

  1. Direct solar-pumped lasers

    Science.gov (United States)

    Lee, J. H.; Shiu, Y. J.; Weaver, W. R.

    1980-01-01

    The feasibility of direct solar pumping of an iodine photodissociation laser at lambda = 1.315 microns was investigated. Threshold inversion density and effect of elevated temperature (up to 670 K) on the laser output were measured. These results and the concentration of solar radiation required for the solar pumped iodine laser are discussed.

  2. Laser-induced nuclear fusion

    International Nuclear Information System (INIS)

    Jablon, Claude

    1977-01-01

    Research programs on laser-induced thermonuclear fusion in the United States, in Europe and in USSR are reviewed. The principle of the fusion reactions induced is explained, together with the theoretical effects of the following phenomena: power and type of laser beams, shape and size of the solid target, shock waves, and laser-hydrodynamics coupling problems [fr

  3. New laser research and development

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    New types of lasers must be developed to provide the desired energy per pulse, pulse length, pulse shape, wavelength, and efficiency for laser-fusion applications. This advanced laser research has focused on rare-gas oxides and on Hg 2 excimers

  4. Coupled optical resonance laser locking

    CSIR Research Space (South Africa)

    Burd, CC

    2014-10-01

    Full Text Available We have demonstrated simultaneous laser frequency stabilization of a UV and IR laser, to coupled transitions of ions in the same spectroscopic sample, by detecting only the absorption of the UV laser. Separate signals for locking the different...

  5. Soft x-ray lasers

    International Nuclear Information System (INIS)

    Matthews, D.L.; Rosen, M.D.

    1988-01-01

    One of the elusive dreams of laser physicists has been the development of an x-ray laser. After 25 years of waiting, the x-ray laser has at last entered the scientific scene, although those now in operation are still laboratory prototypes. They produce soft x rays down to about five nanometers. X-ray lasers retain the usual characteristics of their optical counterparts: a very tight beam, spatial and temporal coherence, and extreme brightness. Present x-ray lasers are nearly 100 times brighter that the next most powerful x-ray source in the world: the electron synchrotron. Although Lawrence Livermore National Laboratory (LLNL) is widely known for its hard-x-ray laser program which has potential applications in the Strategic Defense Initiative, the soft x-ray lasers have no direct military applications. These lasers, and the scientific tools that result from their development, may one day have a place in the design and diagnosis of both laser fusion and hard x-ray lasers. The soft x-ray lasers now in operation at the LLNL have shown great promise but are still in the primitive state. Once x-ray lasers become reliable, efficient, and economical, they will have several important applications. Chief among them might be the creation of holograms of microscopic biological structures too small to be investigated with visible light. 5 figs

  6. Laser Physics and Physics with Lasers - Recent Advances

    International Nuclear Information System (INIS)

    Marowsky, G.

    2008-01-01

    This contribution reviews the development as well as recent technological advances in the field of optics with lasers and laser-related applications. Topics ranging from 'attoscience' to 'zero-modes' shall be dealt with in this presentation. Further reading in the following references is suggested: Springer Handbook of Lasers and Optics (F. Trager, ed.), 2007, ISBN-13: 978-0-387-95579-7; Chapter 11.7, Part C: Ultraviolet Lasers: Excimers, Fluorine (F2), Nitrogen (N2), pp. 764-776; Excimer Laser Technology (D. Basting, G. Marowsky, eds.) 2005, Springer, ISBN-13 978-3-540-20056-7

  7. Tapered diode laser pumped 946 nm Nd:YAG laser

    DEFF Research Database (Denmark)

    Cheng, Haynes Pak Hay; Jensen, Ole Bjarlin; Petersen, Paul Michael

    2009-01-01

    We successfully implemented a 946 nm Nd:YAG laser based on a 808 nm tapered diode pump laser. The tapered diode is developed at the Ferdinand-Braun-Institute fur Hochstfrequenztechnik in Germany. Figure 2 shows the experimental setup and results of each pump source coupled into a 1.5 mm crystal...... laser, we show that tapered diode laser pumping potentially increase the power of 946 nm lasers by a factor of two and reduce the threshold by a factor of three....

  8. Laser solenoid: an alternate use of lasers in fusion power

    International Nuclear Information System (INIS)

    Rose, P.H.

    1977-01-01

    A unique laser assisted fusion approach is under development at Mathematical Sciences Northwest, Inc. (MSNW). This approach captures one of the most developed aspects of high energy laser technology, the efficient, large, scalable, pulsed electron beam initiated, electric discharge, CO 2 infrared laser. This advanced technology is then combined with the simple geometry of a linear magnetic confinement system. The laser solenoid concept will be described, current work and experimental progress will be discussed, and the technological problems of building such a system will be assessed. Finally a comparison will be made of the technology and economics for the laser solenoid and alternative fusion approaches

  9. Laser propulsion for orbit transfer - Laser technology issues

    Science.gov (United States)

    Horvath, J. C.; Frisbee, R. H.

    1985-01-01

    Using reasonable near-term mission traffic models (1991-2000 being the assumed operational time of the system) and the most current unclassified laser and laser thruster information available, it was found that space-based laser propulsion orbit transfer vehicles (OTVs) can outperform the aerobraked chemical OTV over a 10-year life-cycle. The conservative traffic models used resulted in an optimum laser power of about 1 MW per laser. This is significantly lower than the power levels considered in other studies. Trip time was taken into account only to the extent that the system was sized to accomplish the mission schedule.

  10. Laser technologies. KrF laser

    International Nuclear Information System (INIS)

    Owadano, Yoshiro; Okuda, Isao; Matsushima, Isao; Yashiro, Hidehiko; Matsumoto, Yuji

    1994-01-01

    Krypton-fluoride (KrF) laser is one of the promising driver for inertial confinement fusion because of its short wavelength, broad band width, high efficiency and capability of high repetition-rate operation. A high gain double-pass amplifier can yield a high, heavily saturated output intensity (5 to 6 times saturation intensity, > 10MW/cm 2 ) with nearly maximum efficiency (> 10%) and high stage gain (> 50) at the same time. The high gain can be achieved by cylindrical electron-beam pumping configuration without external magnetic field. Angular pulse multiplexing enables efficient pulse compression and amplification of beams with broad spectral width. The broad band width is required for irradiation smoothing methods, BRP (broad-band Random Phase Irradiation) or ISI (Induced Spatial Incoherence). Multi-kJ KrF laser, Super-ASHURA (Electrotechnical Laboratory, 8kJ), NIKE (at Naval Research Laboratory, 3kJ) and TITANIA (Rutherford Appleton Laboratory, 2kJ) are being developed and close to completion. (author)

  11. Joint Laser Interoperability, Tomorrow's Answer to Precision Engagement

    National Research Council Canada - National Science Library

    Neuenswander, David

    2001-01-01

    .... This includes a brief discussion of how a laser works and what constitutes the basic parts of a laser system, laser range finders, laser designators, laser spot trackers, and laser guided weapons...

  12. Proceedings of the conference on lasers and electro-optics

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    This book presents the papers discussed at a conference on the subject of electro-optics and lasers. Some of the topics discussed were: laser fusion and interactions; implosion experiments; tunable integrated Bragg lasers, CO 2 lasers; present status of integrated lasers; DFB lasers; transition metal lasers-solid state lasers, mirror laser resonators, multiquantumwell lasers; fusion laser technology; and dynamics and characteristics of diode lasers

  13. Laser etching as an alternative

    International Nuclear Information System (INIS)

    Dreyfus, R.W.; Kelly, R.

    1989-01-01

    Atoms and molecules are removed from surfaces by intense laser beams. This fact has been known almost since the discovery of the laser. Within the present overall area of interest, namely understanding ion-beam-induced sputtering, it is equally important both to contrast laser etching to ion sputtering and to understand the underlying physics taking place during laser etching. Beyond some initial broad observations, the specific discussion is limited to, and aimed at, two areas: (i) short wavelength, UV, laser-pulse effects and (ii) energy fluences sufficiently small that only monolayers (and not microns) of material are removed per pulse. 38 refs.; 13 figs.; 5 tabs

  14. Laser Program annual report 1984

    International Nuclear Information System (INIS)

    Rufer, M.L.; Murphy, P.W.

    1985-06-01

    The Laser Program Annual Report is part of the continuing series of reports documenting the progress of the unclassified Laser Fusion Program at the Lawrence Livermore National Laboratory (LLNL). As in previous years, the report is organized programmatically. The first section is an overview of the basic goals and directions of the LLNL Inertial Confinement Fusion (ICF) Program, and highlights the year's important accomplishments. Sections 2 through 7 provide the detailed information on the various program elements: Laser Systems and Operations, Target Design, Target Fabrication, Laser Experiments and Advanced Diagnostics, Advanced Laser Development, and Applications of Inertial Confinement Fusion. Individual sections will be indexed separately. 589 refs., 333 figs., 25 tabs

  15. Lasers and uranium isotope separation

    Energy Technology Data Exchange (ETDEWEB)

    Gilles, L

    1987-12-01

    The use of lasers by the electronuclear industry to enrich uranium is discussed, particularly economic aspects. The SILMO and SILVA processes (chosen by France for industrial development) are presented. Criteria which lead to the choice of lasers and to their set-up (architecture of the chain) are described. For electricity - consumption linked to the use of lasers of 40 kWh/STU, a laser uranium enrichment plant with 10 STU/yr capacity requires 50kW of light from copper vapor lasers, i.e., 500 units each having 100W capacity, compared with the 40W units currently marketed.

  16. Aurora laser optical system

    International Nuclear Information System (INIS)

    Hanlon, J.A.; McLeod, J.

    1987-01-01

    Aurora is the Los Alamos short-pulse high-power krypton fluoride laser system. It is primarily an end-to-end technology demonstration prototype for large-scale UV laser systems of interest for short-wavelength inertial confinement fusion (ICF) investigations. The system is designed to employ optical angular multiplexing and aerial amplification by electron-beam-driven KrF laser amplifiers to deliver to ICF targets a stack of pulses with a duration of 5 ns containing several kilojoules at a wavelength of 248 nm. A program of high-energy density plasma physics investigations is now planned, and a sophisticated target chamber was constructed. The authors describe the design of the optical system for Aurora and report its status. This optical system was designed and is being constructed in two phases. The first phase carries only through the amplifier train and does not include a target chamber or any demultiplexing. Installation should be complete, and some performance results should be available. The second phase provides demultiplexing and carries the laser light to target. The complete design is reported

  17. Coherent laser vision system

    International Nuclear Information System (INIS)

    Sebastion, R.L.

    1995-01-01

    The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system

  18. Laser driven particle acceleration

    International Nuclear Information System (INIS)

    Faure, J.

    2009-06-01

    This dissertation summarizes the last ten years of research at the Laboratory of Applied Optics on laser-plasma based electron acceleration. The main result consists of the development and study of a relativistic electron source with unique properties: high energy (100-300 MeV) in short distances (few millimeters), mono-energetic, ultra-short (few fs), stable and tunable. The manuscript describes the steps that led to understanding the physics, and then mastering it in order to produce this new electron source. Non linear propagation of the laser pulse in the plasma is first presented, with phenomena such as non linear wakefield excitation, relativistic and ponderomotive self-focusing in the short pulse regime, self-compression. Acceleration and injection of electrons are then reviewed from a theoretical perspective. Experimental demonstrations of self-injection in the bubble regime and then colliding pulse injection are then presented. These experiments were among the first to produce monoenergetic, high quality, stable and tunable electron beams from a laser-plasma accelerator. The last two chapters are dedicated to the characterization of the electron beam using transition radiation and to its applications to gamma radiography and radiotherapy. Finally, the perspectives of this research are presented in the conclusion. Scaling laws are used to determine the parameters that the electron beams will reach using peta-watt laser systems currently under construction. (author)

  19. Fiber Lasers V

    DEFF Research Database (Denmark)

    Hansen, Kim P.; Olausson, Christina Bjarnal Thulin; Broeng, Jes

    2008-01-01

    laser system. We present the latest advancements within airclad fiber technology including a new 70 μm single-mode polarization-maintaining rod-type fiber capable of amplifying to MW power levels. Furthermore we describe the novel airclad based pump combiners and their use in a completely monolithic 350...

  20. Vertical cavity laser

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention provides a vertical cavity laser comprising a grating layer comprising an in-plane grating, the grating layer having a first side and having a second side opposite the first side and comprising a contiguous core grating region having a grating structure, wherein an index...

  1. Infrared diode laser spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Civiš, Svatopluk; Cihelka, Jaroslav; Matulková, Irena

    2010-01-01

    Roč. 18, č. 4 (2010), s. 408-420 ISSN 1230-3402 R&D Projects: GA AV ČR IAA400400705 Institutional research plan: CEZ:AV0Z40400503 Keywords : FTIR spectroscopy * absorption spectroscopy * laser diodes Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.027, year: 2010

  2. Laser Soap Fountain

    Science.gov (United States)

    Foley, Tyler; Pegram, Matthew; Jenkins, Zachary; Hester, Brooke C.; Burris, Jennifer L.

    2015-01-01

    We have developed an eye-catching demonstration that showcases a variety of physics topics from total internal reflection to electrostatics to non-Newtonian fluid dynamics, including the Kaye effect. The essential components of the demonstration include a vertical stream of liquid soap in which a laser pointer is internally reflected, and which…

  3. Laser microirradiation of cells

    International Nuclear Information System (INIS)

    Berns, M.W.; Kitzes, M.; Rattner, J.B.; Burt, J.; Meredith, S.

    1979-01-01

    The brief review outlines the technique of laser microbeam irradiation (260 - 700 nm) of cells to study ultrastructural changes. In combination with other techniques such as optical microscopy, electron microscopy and autoradiography structure and organization of chromosomes and nucleoli, chromosome stability, mechanisms of mitosis, gene mapping, cytoplasmic functions, and structure of nucleic acids are investigated

  4. Laser surveillance system (LASSY)

    International Nuclear Information System (INIS)

    Boeck, H.; Hammer, J.

    1988-01-01

    The development progress during the reporting period 1988 of the laser surveillance system of spent fuel pools is summarized. The present engineered system comes close to a final version for field application as all technical questions have been solved in 1988. 14 figs., 1 tab. (Author)

  5. LASIK - Laser Eye Surgery

    Science.gov (United States)

    ... Refractive Surgery Procedures What Is Photorefractive Keratectomy (PRK)? LASIK — Laser Eye Surgery Leer en Español: LASIK—Cirugía ocular con láser ... loss of close-up focusing power. How the LASIK procedure works LASIK is performed while the patient ...

  6. Laser particulate spectrometer

    Science.gov (United States)

    Boyd, B. A.; Linford, R. M. F.; Schmitt, R. J.

    1977-01-01

    Hybrid laser scattering and extinction technique measures particle diameters from 0.8 to 2.75 micrometers and speeds from 0.2 to 20 m/s. Operating pressures range from ambient to ultra-high vacuum, and temperatures range from 77 to 300 K. Potential applications include air pollution, clean room, and particle size monitoring.

  7. Laser therapy in sinusitis

    International Nuclear Information System (INIS)

    Hernandez Diaz, Adel; Orellana Molina, Alina; Larrea Cox, Pedro; Combarro Romero, Andres; Corcho Corcho, Carlos; Morales Valdes, Omar; Gonzalez Mendez, Bianka M.

    2009-01-01

    The sinusitis is an inflammation of one or more breasts peri-nasals. It is common in the months of winter and it can last months or years if it is not treat. At the moment we have several means that try to offer our patients a better treatment. One of these instruments is the low power laser that for their properties to the interaction with the biological tissues offers therapeutic effects on the alive tissues, achieving at the level cellular important changes for a quick answer of the damaged tissue. We intended to demonstrate the effectiveness of the treatment with low power laser in patient with sinusitis. It was carried out an explanatory and retrospective study, where it was applied as treatment the low power laser, for that which a team of model Cuban production Fisser 21. The feminine sex, the affected age group prevailed it was among 36 to 50 years for both groups, the maxillary sinusitis prevailed regarding the frontal. The migraine, the nasal obstruction and the sensation of congestion of the head were present in most of the cases. 75% of the patients' treaties noticed improvement of the symptoms between the 1st and 3rd sessions. At the end 80% cured without necessity of a second treatment cycle. The accompanying symptoms almost disappeared in their entirety. We recommend using the treatment of low power laser, as therapy of first line for the treatment of sinusitis of infectious cause. (Author)

  8. Laser surveillance system (LASSY)

    International Nuclear Information System (INIS)

    Boeck, H.

    1991-09-01

    Laser Surveillance System (LASSY) is a beam of laser light which scans a plane above the water or under-water in a spent-fuel pond. The system can detect different objects and estimates its coordinates and distance as well. LASSY can operate in stand-alone configuration or in combination with a video surveillance to trigger signal to a videorecorder. The recorded information on LASSY computer's disk comprises date, time, start and stop angle of detected alarm, the size of the disturbance indicated in number of deviated points and some other information. The information given by the laser system cannot be fully substituted by TV camera pictures since the scanning beam creates a horizontal surveillance plan. The engineered prototype laser system long-term field test has been carried out in Soluggia (Italy) and has shown its feasibility and reliability under the conditions of real spent fuel storage pond. The verification of the alarm table on the LASSY computer with the recorded video pictures of TV surveillance system confirmed that all alarm situations have been detected. 5 refs

  9. CO2 laser development

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    The research and development programs on high-energy, short-pulse CO 2 lasers were begun at LASL in 1969. Three large systems are now either operating or are being installed. The Single-Beam System (SBS), a four-stage prototype, was designed in 1971 and has been in operation since 1973 with an output energy of 250 J in a 1-ns pulse with an on-target intensity of 3.5 x 10 14 W/cm 2 . The Dual-Beam System (DBS), now in the final stages of electrical and optical checkout, will provide about ten times more power for two-beam target irradiation experiments. Four such dual-beam modules are being installed in the Laser-Fusion Laboratory to provide an Eight-Beam System (EBS) scheduled for operation at the 5- to 10-TW level in 1977. A fourth system, a 100- to 200-TW CO 2 laser, is being designed for the High-Energy Gas Laser Facility (HEGLF) program

  10. Coherent laser vision system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastion, R.L. [Coleman Research Corp., Springfield, VA (United States)

    1995-10-01

    The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system.

  11. Scanning laser Doppler vibrometry

    DEFF Research Database (Denmark)

    Brøns, Marie; Thomsen, Jon Juel

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from...

  12. Confocal laser endomicroscopy

    DEFF Research Database (Denmark)

    Karstensen, John Gásdal; Săftoiu, Adrian; Brynskov, Jørn

    2016-01-01

    BACKGROUND AND STUDY AIMS: Confocal laser endomicroscopy (CLE) has been shown to predict relapse in ulcerative colitis in remission, but little is currently known about its role in Crohn's disease. The aim of this study was to identify reproducible CLE features in patients with Crohn's disease...

  13. Laser magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Ferrari, C.A.

    1985-01-01

    The technique of laser resonance magnetic resonance allows one to study the high-resolution spectroscopy of transient paramagnetic species, viz, atoms, radicals, and molecular ions. This article is a brief exposition of the method, describing the principles, instrumentation and applicability of the IR and FIR-LMR and shows results of HF + . (Author) [pt

  14. Laser therapy of muscle injuries.

    Science.gov (United States)

    Dawood, Munqith S; Al-Salihi, Anam Rasheed; Qasim, Amenah Wala'a

    2013-05-01

    Low-level lasers are used in general therapy and healing process due to their good photo-bio-stimulation effects. In this paper, the effects of diode laser and Nd:YAG laser on the healing process of practically managed skeletal muscle trauma has been successfully studied. Standard impact trauma was induced by using a specially designed mechanical device. The impacted muscle was left for 3 days for complete development of blunt trauma. After that it was irradiated by five laser sessions for 5 days. Two types of lasers were used; 785-nm diode laser and 1.064-nm Nd:YAG laser, both in continuous and pulsed modes. A special electronic circuit was designed and implemented to modulate the diode laser for this purpose. Tissue samples of crushed skeletal muscle have been dissected from the injured irradiated muscle then bio-chemically analyzed for the regeneration of contractile and collagenous proteins using Lowry assay for protein determination and Reddy and Enwemeka assay for hydroxyproline determination. The results showed that both lasers stimulate the regeneration capability of traumatized skeletal muscle. The diode laser in CW and pulsed modes showed better results than the Nd:YAG in accelerating the preservation of the normal tissue content of collagenous and contractile proteins beside controlling the regeneration of non-functional fibrous tissue. This study proved that the healing achieved by the laser treatment was faster than the control group by 15-20 days.

  15. Endoscopic laser-urethroplasty

    Science.gov (United States)

    Gilbert, Peter

    2006-02-01

    The objective was to prove the advantage of endoscopic laser-urethroplasty over internal urethrotomy in acquired urethral strictures. Patients and Method: From January, 1996 to June, 2005, 35 patients with a mean age of 66 years were submitted to endoscopic laser-urethroplasty for strictures of either the bulbar (30) or membranous (5) urethra. The operations were carried out under general anesthesia. First of all, the strictures were incised at the 4, 8 and 12 o'clock position by means of a Sachse-urethrotom. Then the scar flap between the 4 and 8 o'clock position was vaporized using a Nd:YAG laser, wavelength 1060 nm and a 600 pm bare fiber, the latter always being in contact with the tissue. The laser worked at 40W power in continuous mode. The total energy averaged 2574 J. An indwelling catheter was kept in place overnight and the patients were discharged the following day. Urinalysis, uroflowmetry and clinical examination were performed at two months after surgery and from then on every six months. Results: No serious complications were encountered. Considering a mean follow-up of 18 months, the average peak flow improved from 7.3 ml/s preoperatively to 18.7 mVs postoperatively. The treatment faded in 5 patients ( 14.3% ) who finally underwent open urethroplasty. Conclusions: Endoscopic laser-urethroplasty yields better short-term results than internal visual urethrotomy. Long-term follow-up has yet to confirm its superiority in the treatment of acquired urethral strictures.

  16. Interband cascade lasers

    International Nuclear Information System (INIS)

    Vurgaftman, I; Meyer, J R; Canedy, C L; Kim, C S; Bewley, W W; Merritt, C D; Abell, J; Weih, R; Kamp, M; Kim, M; Höfling, S

    2015-01-01

    We review the current status of interband cascade lasers (ICLs) emitting in the midwave infrared (IR). The ICL may be considered the hybrid of a conventional diode laser that generates photons via electron–hole recombination, and an intersubband-based quantum cascade laser (QCL) that stacks multiple stages for enhanced current efficiency. Following a brief historical overview, we discuss theoretical aspects of the active region and core designs, growth by molecular beam epitaxy, and the processing of broad-area, narrow-ridge, and distributed feedback (DFB) devices. We then review the experimental performance of pulsed broad area ICLs, as well as the continuous-wave (cw) characteristics of narrow ridges having good beam quality and DFBs producing output in a single spectral mode. Because the threshold drive powers are far lower than those of QCLs throughout the λ = 3–6 µm spectral band, ICLs are increasingly viewed as the laser of choice for mid-IR laser spectroscopy applications that do not require high output power but need to be hand-portable and/or battery operated. Demonstrated ICL performance characteristics to date include threshold current densities as low as 106 A cm −2 at room temperature (RT), cw threshold drive powers as low as 29 mW at RT, maximum cw operating temperatures as high as 118 °C, maximum cw output powers exceeding 400 mW at RT, maximum cw wallplug efficiencies as high as 18% at RT, maximum cw single-mode output powers as high as 55 mW at RT, and single-mode output at λ = 5.2 µm with a cw drive power of only 138 mW at RT. (topical review)

  17. Laser doppler perfusion imaging

    International Nuclear Information System (INIS)

    Waardell, K.

    1992-01-01

    Recording of tissue perfusion is important in assessing the influence of peripheral vascular diseases on the microcirculation. This thesis reports on a laser doppler perfusion imager based on dynamic light scattering in tissue. When a low power He-Ne laser beam sequentally scans the tissue, moving blood cells generate doppler components in the back-scattered light. A fraction of this light is detected by a photodetector and converted into an electrical signal. In the processor, a signal proportional to the tissue perfusion at each measurement site is calculated and stored. When the scanning procedure is completed, a color-coded perfusion image is presented on a monitor. To convert important aspects of the perfusion image into more quantitative parameters, data analysis functions are implemented in the software. A theory describing the dependence of the distance between individual measurement points and detector on the system amplification factor is proposed and correction algorithms are presented. The performance of the laser doppler perfusion imager was evaluated using a flow simulator. A linear relationship between processor output signal and flow through the simulator was demonstrated for blood cell concentrations below 0.2%. The median sampling depth of the laser beam was simulated by a Monte Carlo technique and estimated to 235 μm. The perfusion imager has been used in the clinic to study perfusion changes in port wine stains treated with argon laser and to investigate the intensity and extension of the cutaneous axon reflex response after electrical nerve stimulation. The fact that perfusion can be visualized without touching the tissue implies elimination of sterilization problems, thus simplifying clinical investigations of perfusion in association with diagnosis and treatment of peripheral vascular diseases. 22 refs

  18. Laser-powered lunar base

    International Nuclear Information System (INIS)

    Costen, R.; Humes, D.H.; Walker, G.H.; Williams, M.D.; Deyoung, R.J.

    1989-01-01

    The objective was to compare a nuclear reactor-driven Sterling engine lunar base power source to a laser-to-electric converter with orbiting laser power station, each providing 1 MW of electricity to the lunar base. The comparison was made on the basis of total mass required in low-Earth-orbit for each system. This total mass includes transportation mass required to place systems in low-lunar orbit or on the lunar surface. The nuclear reactor with Sterling engines is considered the reference mission for lunar base power and is described first. The details of the laser-to-electric converter and mass are discussed. The next two solar-driven high-power laser concepts, the diode array laser or the iodine laser system, are discussed with associated masses in low-lunar-orbit. Finally, the payoff for laser-power beaming is summarized

  19. Histologic effects of resurfacing lasers.

    Science.gov (United States)

    Freedman, Joshua R; Greene, Ryan M; Green, Jeremy B

    2014-02-01

    By utilizing resurfacing lasers, physicians can significantly improve the appearance of sun-damaged skin, scars, and more. The carbon dioxide and erbium:yttrium-aluminum-garnet lasers were the first ablative resurfacing lasers to offer impressive results although these earlier treatments were associated with significant downtime. Later, nonablative resurfacing lasers such as the neodymium:yttrium-aluminum-garnet laser proved effective, after a series of treatments with less downtime, but with more modest results. The theory of fractional photothermolysis has revolutionized resurfacing laser technology by increasing the safety profile of the devices while delivering clinical efficacy. A review of the histologic and molecular consequences of the resurfacing laser-tissue interaction allows for a better understanding of the devices and their clinical effects. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  20. 2 micron femtosecond fiber laser

    Science.gov (United States)

    Liu, Jian; Wan, Peng; Yang, Lihmei

    2014-07-29

    Methods and systems for generating femtosecond fiber laser pulses are disclose, including generating a signal laser pulse from a seed laser oscillator; using a first amplifier stage comprising an input and an output, wherein the signal laser pulse is coupled into the input of the first stage amplifier and the output of the first amplifier stage emits an amplified and stretched signal laser pulse; using an amplifier chain comprising an input and an output, wherein the amplified and stretched signal laser pulse from the output of the first amplifier stage is coupled into the input of the amplifier chain and the output of the amplifier chain emits a further amplified, stretched signal laser pulse. Other embodiments are described and claimed.

  1. Semiconductor processing with excimer lasers

    International Nuclear Information System (INIS)

    Young, R.T.; Narayan, J.; Christie, W.H.; van der Leeden, G.A.; Rothe, D.E.; Cheng, L.J.

    1983-01-01

    The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Extensive comparisons of the quality of annealing of ion-implanted Si obtained with XeCl and ruby lasers have been made. The results indicate that irrespective of the large differences in the optical properties of Si at uv and visible wavelengths, the efficiency of usage of the incident energy for annealing is comparable for the two lasers. However, because of the excellent optical beam quality, the XeCl laser can provide superior control of the surface melting and the resulting junction depth. Furthermore, the concentrations of electrically active point defects in the XeCl laser annealed region are 2 to 3 orders of magnitude lower than that obtained from ruby or Nd:YAG lasers. All these results seem to suggest that XeCl lasers should be suitable for fabricating not only solar cells but also the more advanced device structures required for VLSI or VHSIC applications

  2. Laser engineering of microbial systems

    Science.gov (United States)

    Yusupov, V. I.; Gorlenko, M. V.; Cheptsov, V. S.; Minaev, N. V.; Churbanova, E. S.; Zhigarkov, V. S.; Chutko, E. A.; Evlashin, S. A.; Chichkov, B. N.; Bagratashvili, V. N.

    2018-06-01

    A technology of laser engineering of microbial systems (LEMS) based on the method of laser-induced transfer of heterogeneous mixtures containing microorganisms (laser bioprinting) is described. This technology involves laser printing of soil microparticles by focusing near-infrared laser pulses on a specially prepared gel/soil mixture spread onto a gold-coated glass plate. The optimal range of laser energies from the point of view of the formation of stable jets and droplets with minimal negative impact on living systems of giant accelerations, laser pulse irradiation, and Au nanoparticles was found. Microsamples of soil were printed on glucose-peptone-yeast agar plates to estimate the LEMS process influence on structural and morphological microbial diversity. The obtained results were compared with traditionally treated soil samples. It was shown that LEMS technology allows significantly increasing the biodiversity of printed organisms and is effective for isolating rare or unculturable microorganisms.

  3. Solid-State Random Lasers

    CERN Document Server

    Noginov, Mikhail A

    2005-01-01

    Random lasers are the simplest sources of stimulated emission without cavity, with the feedback provided by scattering in a gain medium. First proposed in the late 60’s, random lasers have grown to a large research field. This book reviews the history and the state of the art of random lasers, provides an outline of the basic models describing their behavior, and describes the recent advances in the field. The major focus of the book is on solid-state random lasers. However, it also briefly describes random lasers based on liquid dyes with scatterers. The chapters of the book are almost independent of each other. So, the scientists or engineers interested in any particular aspect of random lasers can read directly the relevant section. Researchers entering the field of random lasers will find in the book an overview of the field of study. Scientists working in the field can use the book as a reference source.

  4. Selective weed control using laser techniques

    OpenAIRE

    Marx, Christian; Pastrana-Perez, Julio; Hustedt, Michael; Barcikowski, Stephan; Haferkamp, Heinz; Rath, Thomas

    2012-01-01

    This contribution discusses technical and growth relevant aspects of using laser techniques for weed control. The research on thermal weed control via laser first focused on the interaction of laser beams and weed plants. Due to preliminary studies, a CO2-laser was selected for further studies with regard to the process factors laser energy, laser spot area, coverage of the weeds meristem, weed species (Amaranthus retroflexus), and weed growth stage. Thereby, the laser damage was modeled in o...

  5. Laser modulator for LISA pathfinder

    Science.gov (United States)

    Voland, C.; Lund, G.; Coppoolse, W.; Crosby, P.; Stadler, M.; Kudielka, K.; Özkan, C.

    2017-11-01

    LISA Pathfinder is an ESA experiment to demonstrate the key technologies needed for the LISA mission to detect gravitational waves in space. The LISA Pathfinder spacecraft represents one arm of the LISA interferometer, containing an optical metrology system and two proof masses as inertial references for the drag-free control system. The LISA Pathfinder payload consists of two drag-free floating test masses located in the inertial sensors with their control electronics and an optical metrology subsystem. The optical metrology subsystem monitors the movement of both test masses relative to each other and to the spacecraft with very high sensitivity and resolution. This is achieved with a heterodyne Mach- Zehnder interferometer. This interferometer requires as input two coherent laser beams with a heterodyne frequency difference of a few kHz. To generate the two laser beams with a heterodyne frequency difference a Nd:YAG laser is used together with the Laser Modulator. The Nd:YAG laser generates a single coherent laser signal at a wavelength of 1064nm which is fibre coupled to the Laser Modulator. The Laser Modulator then generates the two optical beams with the required heterodyne frequency offset. In addition, the Laser Modulator is required to perform laser amplitude stabilization and optical path difference control for the two optical signals. The Laser Modulator consists of an optical unit - the LMU - and RF synthesiser, power amplification and control electronics. These electronics are all housed in the Laser Modulator Electronics (LME). The LMU has four primary functions: • Splitting of the input laser beam into two paths for later superposition in the interferometer. • Applying different frequency shifts to each of the beams. • Providing amplitude modulation control to each of the beams. • Providing active control of the optical path length difference between the two optical paths. The present paper describes the design and performance of the LMU

  6. Electrodeless excimer laser; Laser a eccimeri senza elettrodi

    Energy Technology Data Exchange (ETDEWEB)

    Lisi, N. [ENEA, Divisione Nuovi Materiali, Centro Ricerche Casaccia, Rome (Italy)

    2001-07-01

    In this paper it is proposed how to build an excimer laser based on an electrodeless discharge (or Dielectric Barrier Discharge). Such laser could operate with a low energy per pulse (<100 mJ) and a high repetition rate (<100 kHz). The most relevant advantage an electrodeless DBD laser is the much longer gas mixture lifetime. This feature could allow the operation of a sealed laser emitting higher average power with respect to commercially available excimer lasers. Such discharge scheme could be advantageous in order to excite the F{sub 2} excimer molecule, whose emission wavelength in the VUV range (157 nm) at high reprate is particularly interesting in the micro-lithography field. [Italian] In questo documento viene proposto come costruire un laser a eccimeri basato su una scarica priva di elettrodi, o Dielectric Barrier Discharge. Tale laser puo' funzionare con una bassa energia per impulso (<100 mJ) ad alta frequenza di ripetizione (<100 kHz). Il vantaggio fondamentale di un laser a DBD e quindi privo di elettrodi e' la vita media della miscela gassosa molto piu' alta che potrebbe permettere alla camera laser di operare sigillata ad una potenza media superiore a quella dei laser a eccimeri attuali. Tale schema di pompaggio potrebbe essere particolarmente vantaggioso per eccitare la molecola eccimero F{sub 2} la cui lunghezza di emissione nel VUV (157 nm) ad elevata frequenza di ripetizione presenta un notevole interesse nel campo della produzione di microcircuiti.

  7. Random distributed feedback fibre lasers

    Energy Technology Data Exchange (ETDEWEB)

    Turitsyn, Sergei K., E-mail: s.k.turitsyn@aston.ac.uk [Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET (United Kingdom); Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Babin, Sergey A. [Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Churkin, Dmitry V. [Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET (United Kingdom); Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Vatnik, Ilya D.; Nikulin, Maxim [Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Podivilov, Evgenii V. [Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation)

    2014-09-10

    The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with “negative absorption” of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors–random distributed feedback fibre laser–was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100 km. Although an effective reflection due to the Rayleigh scattering is extremely small (∼0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the

  8. Random distributed feedback fibre lasers

    International Nuclear Information System (INIS)

    Turitsyn, Sergei K.; Babin, Sergey A.; Churkin, Dmitry V.; Vatnik, Ilya D.; Nikulin, Maxim; Podivilov, Evgenii V.

    2014-01-01

    The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with “negative absorption” of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors–random distributed feedback fibre laser–was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100 km. Although an effective reflection due to the Rayleigh scattering is extremely small (∼0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the

  9. Laser spectroscopy on organic molecules.

    Science.gov (United States)

    Imasaka, T

    1996-06-01

    Various laser spectrometric methods have been developed until now. Especially, laser fluorometry is most sensitive and is frequently combined with a separation technique such as capillary electrophoresis. For non-fluorescent compounds, photothermal spectrometry may be used instead. A diode laser is potentially useful for practical trace analysis, because of its low cost and long-term trouble-free operation. On the other hand, monochromaticity of the laser is essential in high-resolution spectrometry, e.g. in low temperature spectrometry providing a very sharp spectral feature. Closely-related compounds such as isomers can easily be differentiated, and information for assignment is obtained from the spectrum. Multiphoton ionization mass spectrometry is useful for soft ionization, providing additional information concerned with molecular weight and chemical structure. A short laser pulse with a sufficient energy is suitable for rapid heating of the solid surface. A matrix-assisted laser desorption/ion-ization technique is recently employed for introduction of a large biological molecule into a vacuum for mass analysis. In the future, laser spectrometry will be developed by a combination with state-of-the-art laser technology. In the 21st century, new laser spectrometry will be developed, which may be based on revolutionary ideas or unexpected discoveries. Such studies will open new frontiers in analytical laser spectroscopy.

  10. Improving the laser brightness of a commercial laser system

    Science.gov (United States)

    Naidoo, Darryl; Litvin, Igor; Forbes, Andrew

    2016-02-01

    We investigate the selection of a flat-top beam and a Gaussian beam inside a laser cavity on opposing mirrors. The concept is tested external to the laser cavity in a single pass and double pass regime where the latter mimics a single round trip in the laser. We implement this intra-cavity selection through the use of two 16 level diffractive optical elements. We consider a solid-state diode side-pumped laser resonator in a typical commercial laser configuration that consists of two planar mirrors where the DOEs are positioned at the mirrors. We out couple the Gaussian and flat-top distributions and we show that we improve the brightness of the laser with active mode control. We also demonstrate that the quality of the beam transformations determine the brightness improvement.

  11. Laser frequency modulator for modulating a laser cavity

    Science.gov (United States)

    Erbert, Gaylen V.

    1992-01-01

    The present invention relates to a laser frequency modulator for modulating a laser cavity. It is known in the prior art to utilize a PZT (piezoelectric transducer) element in combination with a mirror to change the cavity length of a laser cavity (which changes the laser frequency). Using a PZT element to drive the mirror directly is adequate at frequencies below 10 kHz. However, in high frequency applications (100 kHz and higher) PZT elements alone do not provide a sufficient change in the cavity length. The present invention utilizes an ultrasonic concentrator with a PZT element and mirror to provide modulation of the laser cavity. With an ultrasonic concentrator, the mirror element at the end of a laser cavity can move at larger amplitudes and higher frequencies.

  12. Laser systems for on-line laser ion sources

    International Nuclear Information System (INIS)

    Geppert, Christopher

    2008-01-01

    Since its initiation in the middle of the 1980s, the resonant ionization laser ion source has been established as a reliable and efficient on-line ion source for radioactive ion beams. In comparison to other on-line ion sources it comprises the advantages of high versatility for the elements to be ionized and of high selectivity and purity for the ion beam generated by resonant laser radiation. Dye laser systems have been the predominant and pioneering working horses for laser ion source applications up to recently, but the development of all-solid-state titanium:sapphire laser systems has nowadays initiated a significant evolution within this field. In this paper an overview of the ongoing developments will be given, which have contributed to the establishment of a number of new laser ion source facilities worldwide during the last five years.

  13. Development of laser technology in Research Center of Laser Fusion

    International Nuclear Information System (INIS)

    Zheng Wanguo; Deng Ying; Zhou Wei

    2013-01-01

    This paper reviews the progress in the construction of SG-Ⅲ laser facility, integrated Testbed and XG-Ⅲ laser facility and that in the upgrade of the prototype of SG-Ⅲ, and the development in assembling and installing technology, and the achievements in maintaining cleanliness project and metrology in Laser Fusion Research Center, China Academy of Engineering Physics in China in 2012. (authors)

  14. Laser activated superconducting switch

    International Nuclear Information System (INIS)

    Wolf, A.A.

    1976-01-01

    A superconducting switch or bistable device is described consisting of a superconductor in a cryogen maintaining a temperature just below the transition temperature, having a window of the proper optical frequency band for passing a laser beam which may impinge on the superconductor when desired. The frequency of the laser is equal to or greater than the optical absorption frequency of the superconducting material and is consistent with the ratio of the gap energy of the switch material to Planck's constant, to cause depairing of electrons, and thereby normalize the superconductor. Some embodiments comprise first and second superconducting metals. Other embodiments feature the two superconducting metals separated by a thin film insulator through which the superconducting electrons tunnel during superconductivity

  15. An Organic Vortex Laser.

    Science.gov (United States)

    Stellinga, Daan; Pietrzyk, Monika E; Glackin, James M E; Wang, Yue; Bansal, Ashu K; Turnbull, Graham A; Dholakia, Kishan; Samuel, Ifor D W; Krauss, Thomas F

    2018-03-27

    Optical vortex beams are at the heart of a number of novel research directions, both as carriers of information and for the investigation of optical activity and chiral molecules. Optical vortex beams are beams of light with a helical wavefront and associated orbital angular momentum. They are typically generated using bulk optics methods or by a passive element such as a forked grating or a metasurface to imprint the required phase distribution onto an incident beam. Since many applications benefit from further miniaturization, a more integrated yet scalable method is highly desirable. Here, we demonstrate the generation of an azimuthally polarized vortex beam directly by an organic semiconductor laser that meets these requirements. The organic vortex laser uses a spiral grating as a feedback element that gives control over phase, handedness, and degree of helicity of the emitted beam. We demonstrate vortex beams up to an azimuthal index l = 3 that can be readily multiplexed into an array configuration.

  16. CO2 Laser Market

    Science.gov (United States)

    Simonsson, Samuel

    1989-03-01

    It gives me a great deal of pleasure to introduce our final speaker of this morning's session for two reasons: First of all, his company has been very much in the news not only in our own community but in the pages of Wall Street Journal and in the world economic press. And, secondly, we would like to welcome him to our shores. He is a temporary resident of the United States, for a few months, forsaking his home in Germany to come here and help with the start up of a new company which we believe, probably, ranks #1 as the world supplier of CO2 lasers now, through the combination of former Spectra Physics Industrial Laser Division and Rofin-Sinar GMBH. Samuel Simonsson is the Chairman of the Board of Rofin-Sinar, Inc., here in the U.S. and managing director of Rofin-Sinar GMBH. It is a pleasure to welcome him.

  17. Transluminal laser angioplasty

    Science.gov (United States)

    Otto, Wlodzimierz

    1996-03-01

    Twenty seven patients with femoral artery occlusion were treated by transluminal Nd:YAG laser angioplasty, in 16 patients the procedure was combined with intraarterial infusion of rTPA (actilyse-Boehringer Ing). In 5 out of 11 patients from the initial group recanalization was not successful. In 16 patients from the rTPA group satisfactory immediate results were achieved in all cases. In long time observations ranging from 9 to 24 months all patients remained free from symptoms, although in 4 of them angiography and Doppler ultrasound examination reveal no flow in the femoral artery. In the remaining 12 patients (75%), the previously occluded artery is patent. No complications of laser angioplasty nor intraarterial infusion of rTPA were noted in this series.

  18. PEP Laser Surveying System

    International Nuclear Information System (INIS)

    Lauritzen, T.; Sah, R.C.

    1979-03-01

    A Laser Surveying System has been developed to survey the beam elements of the PEP storage ring. This system provides automatic data acquisition and analysis in order to increase survey speed and to minimize operator error. Two special instruments, the Automatic Readout Micrometer and the Small Automatic Micrometer, have been built for measuring the locations of fiducial points on beam elements with respect to the light beam from a laser. These instruments automatically encode offset distances and read them into the memory of an on-line computer. Distances along the beam line are automatically encoded with a third instrument, the Automatic Readout Tape Unit. When measurements of several beam elements have been taken, the on-line computer analyzes the measured data, compared them with desired parameters, and calculates the required adjustments to beam element support stands

  19. Laser resurfacing pearls.

    Science.gov (United States)

    Shah, Sonia; Alam, Murad

    2012-08-01

    Ablative skin resurfacing using the carbon dioxide laser was long considered the gold standard for treatment of photoaging, acne scars, and rhytids. However, conventional full-face carbon dioxide resurfacing is associated with significant risk of side effects and a prolonged postoperative recovery period. Fractional resurfacing has recently revolutionized laser surgery by offering close to comparable results with minimal side effects and a more rapid recovery. Although fractional devices have grown in popularity, and have essentially replaced traditional resurfacing, fractional resurfacing can still be a challenging modality to control precisely due to hardware variations across comparable devices, the range of settings that can be used, and patient-specific considerations. Certain precautions and rules of thumb can reduce the risk associated with fractional resurfacing, and increase the likelihood of a good outcome.

  20. Fusion pumped laser

    Science.gov (United States)

    Pappas, D.S.

    1987-07-31

    The apparatus of this invention may comprise a system for generating laser radiation from a high-energy neutron source. The neutron source is a tokamak fusion reactor generating a long pulse of high-energy neutrons and having a temperature and magnetic field effective to generate a neutron flux of at least 10/sup 15/ neutrons/cm/sup 2//center dot/s. Conversion means are provided adjacent the fusion reactor at a location operable for converting the high-energy neutrons to an energy source with an intensity and energy effective to excite a preselected lasing medium. A lasing medium is spaced about and responsive to the energy source to generate a population inversion effective to support laser oscillations for generating output radiation. 2 figs., 2 tabs.