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Sample records for influencai del ion

  1. Behaviour of the 1-Ascorbic as supporting Electrolyte. Influence of the Magnesium Ion; Comportamiento del acido 1-Ascorbico como electrolito soporte influencai del ion magnesio

    Energy Technology Data Exchange (ETDEWEB)

    Alonso Lopez, J.

    1962-07-01

    The behaviour of 1-ascorbic acid, as supporting electrolyte of the uranyl ion in a 0{sub 1}-0.7 M concentration range, and the influence of pH on the diffusion current and half wave potential of 0,1 M uranyl ion is studied. The cathodic waves from 0 to -2,5 volts, with mercury dropping electrode are studied in fresh 0,1 M aqueous solution in presence of Mg{sup 2}+ and at 2,0-12 pH range. A kinetic current with a half wave potential of 0,85 v. vs. Hg. b.e. is obtained at pH> 9,5 appears a tilth wave a -0,60 v. The pH variation does not influence these potentials. (Author) 18 refs.

  2. TL Dosimetry on the Tandetron Ion Accelerator area of the ININ; Dosimetria TL en el area del Acelerador de iones Tandetron del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Valdovinos A, M.A.; Gonzalez M, P.R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    For the fulfilment of the operation tests of the Positive Ions type Tandetron 4120 MC, 2 MV, it was obtained the permission consented by the National Commission of Nuclear safety and safeguards (CNSNS). During the stage of tests were arranged Tl dosemeters in the Tandetron Accelerator area, as well as toward to the beam exit. In this work, it was presented the results obtained of the measurement of radiation levels, as much in the area as in the beam exit. This Accelerator is useful in different fields of science such as: biology, radiochemistry, materials, solid state physics, archaeology and environmental sciences between others. (Author)

  3. Relationship of the vibrational frequency of the uranyl ion with the uranium electronegativity; Relacion de la frecuencia vibracional del ion uranilo con la electronegatividad del uranio

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez S, A.; Martinez Q, E

    1990-07-15

    It has been demonstrated that the vibrational asymmetric frequency of the uranyl ion, it experiences a consistent spectrochemical displacement with the variations of electronegativity of the uranium in their complexes. The values of the electronegativity of the uranium they were dear by means of calculations that it involves measures of those lengths of the connection uranium-oxygen, obtained by vibrational spectroscopy, effective nuclear charges and the Allred and Rochow equation. The results show the evidence of a natural order that relates to the vibrational frequency with the electronegativity of the uranium atom; settling down that if the electronegativity is graph against it bond length to the oxygen or to it frequency value, a simple relationship is obtained as a form to obtain clear responses in absence of complementary information. (Author)

  4. Cuidados de enfermería a pacientes con trastornos del ion potasio

    OpenAIRE

    Suñé Ysamat, Bertila

    1984-01-01

    La pérdida de potasio de un organismo, y la consiguiente disminución, se llaman hipotasemia. Pero si los niveles de potasio en sangre son muy altos, se habla de hiperpotasemia. En ambos casos se está frente a una alteración del equilibrio del potasio -regulador de la osmolaridad intracelular, influye la conducción del impulso nervioso y la correcta función de los músculos esqueléticos y del cardíaco- que obliga a una determinada analítica. Qué es el potasio? ¿cuál es su importancia para el ho...

  5. MODIFICACION QUIMICA DEL POLIPROPILENO Y SU POTENCIAL USO COMO AGENTE EXTRACTANTE DE IONES METALICOS.

    OpenAIRE

    PEREZ AMARO, LUCIA GABRIELA; PEREZ AMARO, LUCIA GABRIELA

    2008-01-01

    Es de interés en la presente tesis doctoral ampliar el campo de aplicación del polipropileno isotáctico homopolímero (PP) basándose en las propiedades mecánicas, químicas y el bajo costo de producción del polímero. Las excelentes propiedades mecánicas car 176p.

  6. ions

    African Journals Online (AJOL)

    (MP2 B2). In order to draw the final conclusion about the content of the isomers of pentaatomic ions in saturated vapor over cesium chloride, we have taken into account the entropy factor. We considered the isomerization reactions which are given below: Cs3Cl2. + (V-shaped) = Cs3Cl2. + (cyclic or bipyramidal). (1). Cs2Cl3.

  7. Determinación rápida del ion cloruro en yesos, arcillas y cementos

    Directory of Open Access Journals (Sweden)

    Fernández Paris, José M.

    1958-12-01

    Full Text Available Not availableSe describe un método para la determinación del ión cloruro en las arcillas, yesos y cementos, rápido y con un punto de viraje terminante que se corresponde perfectamente con la ecuación estequiométrica que tiene lugar durante la valoración. La individualización del ión mercúrico en exceso mediante la difenilcarbazona ha permitido determinar el ión cloruro mediante una disolución valorada de nitrato mercúrico. El autor ha introducido algunas modificaciones, que cree hacer más fácil la determinación, tales como utilizar los indicadores separadamente, la expresión del cálculo de los resultados, forma de determinar y valorar la disolución de nitrato mercúrico. El tiempo que dura la determinación, incluido el ataque de la muestra, es de cuarenta y cinco minutos para las arcillas y de veinticinco paro los yesos y cementos. Su principal ventaja reside en que la muestra es completamente nítida y transparente durante todo el tiempo que dura la dosificación. Se expone una tabla en la que se pone de manifiesto el paralelismo del método de nitrato mercúrico expuesto con el procedimiento gravimétrico tradicional con nitrato de plata (se ha tomado éste como referencia por su mayor garantía en cuanto a exactitud de los resultados que cualquiera de los procedimientos volumétricos corrientes.

  8. Portable test bench for the studies concerning ion sources and ion beam extraction and focusing systems; Banco de pruebas portatil para el estudio de fuentes de iones y de la extraccion y enfoque del haz de iones

    Energy Technology Data Exchange (ETDEWEB)

    Cordero Lopez, F.

    1961-07-01

    A portable test bench is described, which was designed to check ion sources, ion beam extraction and focusing systems before its use in a 600 KeV Cockcroft-Walton accelerator. The vacuum possibilities of the system are specially analyzed in connection with its particular use. The whole can be considered as a portable accelerator of low energy (50 keV). (Author)

  9. Spectroscopic study; Estudio espectroscopico del PAA con iones de Eu{sup 3+} como material luminescente

    Energy Technology Data Exchange (ETDEWEB)

    Flores, M.; Rodriguez, R. [Departamento de Fisica, Universidad Autonoma Metropolitana Iztapalapa, Mexico D.F. (Mexico); Arroyo, R. [Departamento de Quimica, Universidad Autonoma Metropolitana Iztapalapa, A.P. 55-534, 09340 Mexico D.F. (Mexico)

    1999-07-01

    This work is focused about the spectroscopic properties of a polymer material which consists of Polyacrylic acid (Paa) doped at different concentrations of Europium ions (Eu{sup 3+}). They show that to stay chemically joined with the polymer by a study of Nuclear Magnetic Resonance (NMR) of {sup 1} H, {sup 13} C and Fourier Transform Infrared Spectroscopy (Ft-IR) they present changes in the intensity of signals, just as too when this material is irradiated at {lambda} = 394 nm. In according with the results obtained experimentally in this type of materials it can say that is possible to unify chemically the polymer with this type of cations, as well as, varying the concentration of them, since that these are distributed homogeneously inside the matrix maintaining its optical properties. These materials can be obtained more quickly and easy in solid or liquid phase and they have the best conditions for to make a quantitative analysis. (Author)

  10. Stability constants of the Europium complexes with the chloride ions; Constantes de estabilidad de los complejos del europio con los iones cloruro

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Solache R, M.; Rojas H, A. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

    2000-07-01

    The stability constants of lanthanides complexes with chloride ions which were determined at the same ionic force but in different media, are significantly different. It does not exist a systematic study over these stability constants. The purpose of this work is to determine the stability constants of the europium complexes with chloride ions at 303 K, by the solvents extraction method. (Author)

  11. Design of the magnetic system of an ECR type ion source; Diseno del sistema magnetico de una fuente de iones tipo ECR

    Energy Technology Data Exchange (ETDEWEB)

    Camps C, E.; Munoz C, A

    1990-05-15

    A computer program written with the purpose of studying the magnetic field produced by a linear system of n coils is shown. Based on this a four coils system is designed that was used in an ion source of Resonance Electron-cyclotron type (REC) that is sought to build. In turn, structure characteristics of the magnetic field proper for such purpose are discussed. (Author)

  12. Installation, tests and start up of the Tandetron positive ions accelerator; Instalacion, pruebas y arranque del acelerador de iones positivos Tandetron

    Energy Technology Data Exchange (ETDEWEB)

    Valdovinos A, M.A.; Hernandez M, V. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Mexico D.F. (Mexico)

    2000-07-01

    The National Institute of Nuclear Research acquired a Positive ions accelerator type Tandetron 2MV of the Dutch Company High Voltage Engineering, Europe B.V. (H.V.E.E.) which was installed in the building named Irradiator Nave which is occupied by the Gamma irradiator and the Pelletron accelerator. Starting from the accelerator selection it was defined the conditions required for the operation of this as well as: electric feeding, water quality and quantity, air compressed, temperature, humidity, etc.; as well as the necessary modifications of the installation area. (Author)

  13. TL dosimetry in the new Tandetron ion accelerator site of the National Institute of Nuclear Research (ININ); Dosimetria TL en el area del nuevo acelerador de iones Tandetron del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Valdovinos A, M.; Gonzalez M, P.R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The National Institute of Nuclear Research (ININ) acquired a positive ions accelerator type Tandetron 2 MV of the dutch company High Voltage Engineering, Europe B.V., which was finished its installation this year (2000) in an already existing building in the Dr. Nabor Carrillo Flores Nuclear Centre, where it was prepared for the following purposes: the accelerator will be used to realize research through X-ray emission induced by charged particles, Rutherford backscattering analysis, nuclear reaction analysis, gamma ray emission induced by charged particles, resonant dispersion analysis, elastic backward detection analysis and by particle canalization analysis. The accelerator consists of an injection system with two ion sources, ion accelerator tank with voltage in terminal at 2 MV, recovery and recirculation system of charge interchange gas, iman selector analyzer system and with high energy focussing, control system through computer and management and recovery of isolator gas system. For the realization of operation tests of this accelerator, it was had the license authorizing by the National Commission of Nuclear Safety and Safeguards (CNSNS). During the test stage Tl dosemeters were arranged in the Tandetron accelerator area, and also in direction to the beam outlet. In this work, are presented the obtained results of the measurement of radiation levels, as in the area as in the beam outlet. (Author)

  14. Tipificación molecular del Virus Papiloma Humano en mujeres con lesiones cervicales de alto grado y cáncer de cérvix atentidas en el área de colposcopía en consulta externa del ION Solca Guayaquil, periodo 2013 - 2014.

    OpenAIRE

    Morocho Molina, Nancy Jannet

    2015-01-01

    El Virus del Papiloma Humano (VPH) está asociado directamente con el desarrollo del cáncer de cérvix. Objetivo: tipificación y asociación de VPH de alto riesgo en pacientes con LIEAG y cáncer de cérvix que acudieron a la consulta externa del ION SOLCA-GUAYAQUIL, durante el período 2013- 2014. Metodología: el presente estudio fue de tipo descriptivo, observacional y analítico, los exámenes utilizados fueron el papanicolaou, colposcopia, biopsia de cérvix y tipificación viral del VPH medi...

  15. Complejación de la resina de intercambio de iones: enmascaramiento del sabor amargo de cefuroxime acetil Ion-exchange resin complexation: Masking the bitter taste of cefuroxime axetil

    Directory of Open Access Journals (Sweden)

    Inderbir Singh

    2011-06-01

    Full Text Available OBJECTIVE: the purpose of this research was to formulate taste masked complexes of cefuroxime axetil and to evaluate them for taste, drug loading and characterized by FTIR, XRD. Tablets were formulated of selected batches and evaluated for drug release and physical parameters. METHODS: complexation technique is used to prepare complexes of drug where ion exchange resins such as Indion® 214, Indion® 234 and Indion® 414 were used with a drug-resin ratio of 1:0.5, 1:1, 1:2. The drug resinates were characterized by Infrared Spectroscopy, DSC and X-Ray Diffraction pattern and evaluated for drug loading and taste. Direct compression method was used to formulate tablets. In vitro dissolution was carried out using USP II apparatus. RESULT: potential taste masking increased with increasing concentration of resin. Indion® 214 resin showed better taste masking effect as compared to Indion® 234 and Indion® 414. Percent of drug loading was maximum at drug : resin ratio of 1:1, after that it decreased. Prolonged (upto 5 h and slow drug release was observed with resin 214 at higher concentration. CONCLUSIONS: out of three resins chosen, Indion® 214 at higher concentration exhibit excellent taste masking as well as sustained drug release action.OBJETIVO: el objetivo de esta investigación fue formular los complejos con sabor amargo de cefuroxime acetil y evaluarlos por sabor, carga medicamentosa y caracterización por FTIR, XRD. Las tabletas fueron formuladas a partir de lotes seleccionados y evaluados en busca de la liberación medicamentosa y parámetros físicos. MÉTODOS: la técnica de complejación se utilizó para preparar complejos farmacológicos donde las resinas de intercambio iónico como Indion® 214, Indion® 234 y el Indion® 414 se emplearon a una proporción resina-medicamento de 1:0.5, 1:1, 1:2. Los resinados medicamentosos fueron caracterizados mediante espectroscopia infrarroja, DSC y el patrón de difracción-rayos-X, y evaluados

  16. Microscale adaptation of the potentiometric method with ion-selective electrode for the quantification of fluoride; Adaptacion a microescala del metodo potenciometrico con electrodo ion selectivo para la cuantificacion de fluoruro

    Energy Technology Data Exchange (ETDEWEB)

    Guevara Ruiz, Paulina; Ortiz Perez, Maria Deogracias [Laboratorio de Bioquimica, Facultad de de Medicina, Universidad Autonoma de San Luis Potosi, San Luis Potosi, San Luis Potosi, (Mexico)]. E-mail: mdortiz@uaslp.mx

    2009-05-15

    muestra necesarios, disminuya costo y substancias de desecho. Se valido el metodo potenciometrico establecido en la NMX-AA-077-SCFI-2001, asi como el metodo a microescala propuesto en este trabajo; posteriormente, se compararon ambos metodos mediante graficos y calculos estadisticos. Ademas se analizaron por ambos metodos 125 muestras de agua embotellada de venta en la ciudad de San Luis Potosi. Los datos de la validacion del metodo fueron optimos para su desempeno. Los resultados de la determinacion en las muestras de agua embotellada por ambos metodos, indican que la modificacion a microescala es estadisticamente comparable al metodo potenciometrico con electrodo ion selectivo. El metodo propuesto a microescala es apropiado para su utilizacion, con una reduccion de 95 % en costo y desechos generados.

  17. Fluoride ions sorption of the water using natural and modified hematite with aluminium hydroxide; Sorcion de iones fluoruro del agua utilizando hematita natural y hematita acondicionada con hidroxido de aluminio

    Energy Technology Data Exchange (ETDEWEB)

    Teutli S, E. A.

    2011-07-01

    Fluorine is a mineral known for its dental benefits, but fluoride ions can cause fluoro sis in excessive quantities. There are many epidemiological studies on possible adverse effects resulting from prolonged ingestion of fluoride through drinking water. These studies demonstrate that fluoride mainly affects the bone tissue (bones and teeth), may produce an adverse effect on tooth enamel and can cause mild dental fluoro sis at concentrations from 0.9 to 1.2 mg/L in drinking water. In several states of Mexico, water contaminated with fluoride ions can be found, such as Aguascalientes, Chihuahua, Coahuila, Durango, Guanajuato, Sonora, Zacatecas, San Luis Potosi and Jalisco, where the fluoride ions levels are higher than 1.5 mg/L, established by the Mexican Official Standard (NOM-127-Ssa-2000) which sets the permissible limits of water for human use and consumption. Currently, several technologies have been proposed to remove fluoride ions from water such as precipitation methods which are based on the addition of chemicals to water and sorption methods to removed fluoride ions by sorption or ion exchange reactions by some suitable substrate capable of regenerate and reuse. In this work, the sorption of fluoride ions using unmodified and modified hematite with aluminum hydroxide to remove fluoride ions from water by bath experiments was studied. The hematite was modified by treating it with aluminum hydroxide, NaOH and Al{sub 2}(SO{sub 4}){sub 3} solutions. The characterization of hematite before and after modification with aluminum hydroxide was studied by X-ray diffraction, scanning electron microscopy, EDS and Bet. The effect of ph, contact time, concentration of fluoride ions, and the dose of sorbent on the sorption of fluoride ions by the modified hematite were studied. Equilibrium was reached within 48 hours of contact time and the maximum sorption of fluoride ions were in the range pH{sub eq} between 2.3 and 6.2. Sorption capacities of fluoride ions as a

  18. Comparative study of adsorbents for the removal of fluoride ions from water use and consumption in Mexico; Estudio comparativo de adsorbentes para la remocion de iones fluoruro del agua de uso y consumo en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Teutli S, E. A.

    2014-07-01

    Although fluoride is essential for health many studies have shown it is associated with some health problems, such as fluoro sis, thyroid disorder, neurological disease, Alzheimer, pineal gland and cancer. One of the major routes of exposure is through drinking water. The World Health Organization (Who) allows only 1.5 mg/L as a safe limit for fluoride ions in drinking water and the EPA U. S. Environmental Protection Agency has recently proposed 0.7 mg/L. In some cases, the water extracted from deep wells has concentrations of fluoride ions above 1.5 mg/L (NOM-127-SSA1-2000) which is the permissible limit of water for human use and consumption (whuc). In several countries, there are high concentrations of fluoride ions due to the geological distribution of fluorine-rich rocks. In our country we can find several states that have concentrations higher than 1.5 mg/L of fluoride ions in water, such as Aguascalientes, Zacatecas, Chihuahua, Coahuila, Durango, Guanajuato, Sonora, Jalisco and San Luis Potosi. Various technologies have been proposed to remove fluoride ions from water, such as adsorption, ion exchange, reverse osmosis, nano filtration, electrodialysis, dialysis and electrocoagulation. Sorption is superior to other techniques in terms of initial cost, simplicity of design and ease of operation. In this work systematic studies were done considering the aspects mentioned above, in order to determine the adsorbents properties and most suitable conditions for the removal of fluoride ions from whuc. It is important to note that to date no adsorption treatments for the removal of fluoride ions from water for human use and consumption in our country is done, although there are established methodologies, they have not been implemented because of their high costs. In this work an integral study was done on the removal of fluoride ions from water for human use and consumption. A comparative study of hematite, calcite and zeolite as adsorbents was performed to develop a

  19. Establishment of the conditions for the determination of the concentration of the uranyl ion in perchloric media by Fluorescence; Establecimiento de las condiciones para la determinacion de la concentracion del ion uranilo en medio perclorico por Fluorescencia

    Energy Technology Data Exchange (ETDEWEB)

    Contreras R, A.; Ordonez R, E.; Fernandez V, S.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: contraida@yahoo.com.mx

    2004-07-01

    The influence of the p H is reported in the spectra of luminescence of the ion uranyl in sodium perchlorate 2M. The best spectra were observed to ph <3 that to neutral and basic p Hs this is explained by the present species. They were carried out four calibration curves for the uranyl in perchloric acid media, taking into account the area under the curve, the maximum height of two characteristic peaks of this ion, in those that one observes a better correlation with the maximum height of the peak located to 486.7 nm. (Author)

  20. Conversaçiones de Música a finals del segle XVI: el cas de l’acadèmia de Joan de Borja i Castro

    Directory of Open Access Journals (Sweden)

    Ferran Escrivà-Llorca

    2017-06-01

    Full Text Available Resum: Aquest article s’insereix dins del conjunt d’investigacions sobre la Cort dels Habsburgs. L’estudi de les acadèmies musicals és poc conegut. A partir d’algunes investigacions sobre acadèmies literàries, l’article focalitzarà en l’acadèmia musical que Joan de Borja i Castro tenia a Madrid. En aquest sentit, si el mecenatge literari cortesà ja és un tema amb múltiples variants, l’aproximació al patrocini d’altres activitats artístiques, com el cas de la música, ho és encara més. En les següents pàgines s’aprofundirà en les diverses facetes erudites de Joan de Borja amb el fil conductor de les acadèmies, com a centre d’intel·lectualitat, de creació i promoció cultural i també personal. Per aquesta acadèmia van passar alguns dels personatges del món musical ibèric més important de l’època com Francisco Guerrero o Tomás Luis de Victoria. Aquest article pretén mostrar la importància d’aquesta acadèmia com un punt neuràlgic del mecenatge musical de les darreres dècades del segle XVI.   Paraules clau: Joan de Borja, Borja, acadèmies, Habsburgs, Música, Madrid   Abstract: This work is part of the research on The Court of Habsburg in Modern Era. The study of music academies is not quite known. From few works on literary academies, this article will focus on the music academy that of Juan de Borja i Castro hold in Madrid. In this way, if the courtly literary patronage is already an issue with multiple variants, the approach to other artistic activities, such as the music, it is even more. In the following pages, it will delve into the various aspects of erudition of Juan de Borja with the thread of the academies, as a centre of intellectual, creative and cultural promotion and personal. Some of the most important composers of the Iberian World of that time, such as Francisco Guerrero or Tomás Luis de Victoria, were involved in this academy. The article aims to show the relevance of this

  1. Determination of the stability of the uranyl ion sipped in {tau}-hydrogen phosphate of zirconium in sodic form; Determinacion de la estabilidad del ion uranilo sorbido en {tau}-hidrogenofosfato de zirconio en forma sodica

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez R, E.; Fernandez V, S.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Drot, R.; Simoni, E. [Universite de Paris-Sud-XI, Institut de Physique Nucleaire d' Orsay, Groupe de radiochimie, Bat. 100, 91406 Orsay (France)]. e-mail: edo@nuclear.inin.mx

    2005-07-01

    The stability of the uranyl sipped in the zirconium {tau}-hydrogen phosphate in sodic form ({tau}-NaZrP), was carried out characterizing the complexes formed by Laser spectroscopy in the visible region and by X-ray photoelectron spectroscopy. The material was prepared by a new synthesis technique working in nitrogen atmosphere and to low temperatures. The sorption of the uranyl ion was made in acid media with concentrations of 10{sup -4} and 10{sup -5} of uranyl nitrate and with ion forces of 0.1 and 0.5 M of NaClO{sub 4}. The spectra of induced fluorescence with laser (TRLFS) show that the uranyl is fixed in very acid media in three well differentiated species, to pH less acid, the specie of long half life disappears and are only those of short half life. The results of the binding energy obtained by XPS indicate that the binding energy of the uranyl confer it a stable character to the complex formed in the {tau}-NaZP, that makes to this material appropriate to retain to the uranyl in solution to high ion forces and in acid media. (Author)

  2. Effect of the ion force on the hydrolysis constants and of the solubility product of Europium; Efecto de la fuerza ionica sobre las constantes de hidrolisis y del producto de solubilidad del europio

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Ramirez G, J.J.; Solache R, M.; Rojas H, A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    A study on the behavior of the first hydrolysis constant {beta}{sub Eu,H}{sup l-0} and the constant of the solubility product Kps of the europium in front of the changes of the ion force: 0. 02 M, 0.1 M, 0.7M, 2M, 3M and 4M of sodium perchlorate, at 303 K. Experimentally the potentiometry and also radioactivity measures its were used. The specific interaction of ions theory (SIT) of Bronsted-Guggenheim-Scatchard allows the extrapolation of the values to infinite dilution and the results were: log {beta}{sub Eu,H}{sup l-0} = -7 36 and log K{sub sp}{sup l-0} = -24. 68. A discussion of the group of results with the data of the literature is presented. (Author)

  3. Estudio de la resistencia a la corrosión localizada del acero inoxidable superaustenítico 24,1Cr22Ni7,1Mo en mezclas que contienen iones cloruro y cloruro-fluoruro

    Directory of Open Access Journals (Sweden)

    Pardo Gutiérrez del Cid, Angel

    2001-08-01

    Full Text Available The localised corrosion resistance (pitting and crevice corrosion of the high alloy 24.1Cr22Ni7.1Mo superaustenitic stainless steel has been studied in solutions with chloride concentrations between 200 and 6.000 ppm. A similar study has been carried out using mixtures of equal concentrations of chloride and fluoride ions in the range of 400 to 12.000 ppm. pH values varied from 2 to 6.5. The critical temperatures for pitting and crevice corrosion have been calculated for these test media using electrochemical techniques (direct current. From the results obtained by cyclic polarisation, the critical pitting temperature (CPT and the critical crevice temperature (CCT have been determined for this material in each of tested media. The resistance of this material to localised corrosion is high, mainly due to the high repassivation rate in the tested media. At the highest tested concentration of chloride and fluoride ions and at pH 6.5, the material undergoes a generalised attack.

    Se estudia la resistencia a la corrosión localizada (picadura y resquicio del acero inoxidable superaustenitico 24,1Cr22Ni7,1Mo, cuando opera en soluciones que contienen concentraciones de iones cloruro entre 200 y 6.000 ppm. Así mismo se estudia el comportamiento en mezclas que contienen concentraciones iguales de iones cloruro y fluoruro entre 400 y 12.000 ppm. El intervalo de pH utilizado se situó entre 2 y 6,5. Las temperaturas críticas de picadura y resquicio se calcularon mediante técnicas electroquímicas de corriente continua. A partir de los resultados obtenidos mediante polarización cíclica, se han obtenido tanto las temperaturas críticas de picadura (TCP como las de resquicio (TCR para el material en cada uno de los medios ensayados. La resistencia de este material a la corrosión localizada es alta, debido principalmente a la elevada capacidad de repasivación en los medios de ensayo empleados. Para la mayor concentración de iones cloruro y

  4. International Conference on Surface Modification of Metals by Ion Beams Held in Riva Del Garda, Italy on 12-16 September 1988 (Final Program and Abstracts)

    Science.gov (United States)

    1988-09-16

    supported by the Institute for Scientific and Technological Research (IRST, a branch of ITC -Istituto Trentino di Cultura - Trento, Italy), the Physics...sputtering of Ti in a nitrogen-rich ambient (RF sputtering) and by N-implantation during vapor-deposition of Ti thin films (Ion Beam Enhanced Deposition... ambient . The distribution of implanted oxygen and nitrogen before and after annealing was measured by means of AES combined with argon sputtering. The

  5. Variaciones del ión potasio durante el ayuno del Ramadán: Resultados preliminares en jóvenes musulmanes Changes of the potassium ion during the fast of Ramadan: Preliminary outcomes

    OpenAIRE

    R. Guerrero Morilla; J. Ramírez Rodrigo; A. Sánchez Caravaca; G. Ruiz Villaverde; B. A. Pérez Moreno; C. Villaverde Gutiérrez

    2011-01-01

    Justificación y objetivos: El precepto islámico del Ramadán (R) impone a las personas que lo practican, importantes modificaciones fisiológicas y psicológicas, debido a las restricciones hídricas y dietéticas a las que se ven sometidos durante las horas diurnas a lo largo de un mes, estableciendo un modelo intermitente de ayuno absoluto, de naturaleza singular, particularmente cuando éste se lleva a cabo en sociedades multiculturales de tipo occidental, en las que no se producen ajustes horar...

  6. Uso de las cenizas volantes del carbón en la síntesis de materiales zeolíticos con propiedades intercambiadoras de ion amonio

    Directory of Open Access Journals (Sweden)

    Jaime Olmedo Pérez O.

    2010-10-01

    Full Text Available En esta investigación se sintetizan las zeolitas F y W a partir de reactivos grado analítico y de las cenizas volantes de carbón como fuentes de aluminio y silicio. El propósito de la síntesis de estos materiales es mostrar la posibilidad económica de su obtención y su aplicación potencial en la remoción de ion amonio, en general, de aguas de desecho y específicamente de aguas de cultivos piscícolas.

  7. Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor; Inmovilizacion de resinas de intercambio ionico radiactivas del reactor nuclear Triga Mark III

    Energy Technology Data Exchange (ETDEWEB)

    Garcia M, H.; Emeterio H, M.; Canizal S, C. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

    2000-07-01

    This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

  8. Impacts of lost fast ions on the TJ-II Vacuum Vessel during NBI; Impactos de los iones rapidos en la Camara de Vacio del TJ-II durante NBI

    Energy Technology Data Exchange (ETDEWEB)

    Guasp, J.

    1995-07-01

    The possible deposition patterns, on the Vacuum Vessel, of lost fast ions during the balanced tangential NBI in TJ-II helical axis Stellarator are analysed theoretically, establishing the relation between those impact points, the plasma exit and birth positions and the magnetic configuration characteristics. It is shown that direct losses are the most important, mainly those produced by the beam injected with the same direction that the magnetic field, increasing with beam energy and plasma density but with impacts remaining fixed on well defined zones, a periodically distributed along the Hard Core cover plates, producing high loads at high densities. The remaining losses, except for the shine through ones that predominate at low density, are periodically distributed, with smooth maxima and produce very low loads. No overlapping between the different kind of losses or beams is observed. (Author) 6 refs.

  9. Establishment of a luminescence technique for the quantification of uranyl ion in a KNO{sub 3} media; Establecimiento de una tecnica de luminiscencia para la cuantificacion del ion uranilo en medio de KNO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Contreras R, A. [UAEM, A.P. 2-139, 50000 Toluca, Estado de Mexico (Mexico); Fernandez V, S.M.; Ordonez R, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2005-07-01

    The study of the storage of high level radioactive residuals that contain uranium, it makes necessary that in the sorption studies is counted with a reliable technique and not pollutant for the quantification of this element. Presently work intends a technique for the quantification of the uranyl ion using the luminescence technique, which allows not to generate radioactive or industrial residuals. It was used a solution of uranyl nitrate in KNO{sub 3} 0.5 M media. The solutions were adjusted to a pH of 1.48+0.03. A statistical study for the analysis of the data of fluorescence, about the maximum value of the peak, total area under the curve and area under the it curves is shown, being the best correlation for the concentration curve versus maximum of the peak, adjusted with a polynomial of second grade. The study of stability of the solutions with regard to the time is reported and that the technique proposal works for the interval of concentrations among 1 x 10{sup -2} M and 6 x 10{sup -5} M. (Author)

  10. Ion Colliders

    CERN Document Server

    Fischer, W

    2014-01-01

    High-energy ion colliders are large research tools in nuclear physics to study the Quark-Gluon-Plasma (QGP). The range of collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead and uranium. Asymmetric collision combinations (e.g. protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders, the Relativistic Heavy Ion Collider (RHIC) at BNL, and the Large Hadron Collider (LHC) at CERN.

  11. Ion colliders

    International Nuclear Information System (INIS)

    Fischer, W.

    2010-01-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions (77Asb1, 81Bou1). The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  12. Ion colliders

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W.

    2011-12-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions [77Asb1, 81Bou1]. The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  13. ion irradiation

    Indian Academy of Sciences (India)

    Swift heavy ions interact predominantly through inelastic scattering while traversing any polymer medium and produce excited/ionized atoms. Here samples of the polycarbonate Makrofol of approximate thickness 20 m, spin coated on GaAs substrate were irradiated with 50 MeV Li ion (+3 charge state). Build-in ...

  14. DelPhi: a comprehensive suite for DelPhi software and associated resources

    Directory of Open Access Journals (Sweden)

    Li Lin

    2012-05-01

    Full Text Available Abstract Background Accurate modeling of electrostatic potential and corresponding energies becomes increasingly important for understanding properties of biological macromolecules and their complexes. However, this is not an easy task due to the irregular shape of biological entities and the presence of water and mobile ions. Results Here we report a comprehensive suite for the well-known Poisson-Boltzmann solver, DelPhi, enriched with additional features to facilitate DelPhi usage. The suite allows for easy download of both DelPhi executable files and source code along with a makefile for local installations. The users can obtain the DelPhi manual and parameter files required for the corresponding investigation. Non-experienced researchers can download examples containing all necessary data to carry out DelPhi runs on a set of selected examples illustrating various DelPhi features and demonstrating DelPhi’s accuracy against analytical solutions. Conclusions DelPhi suite offers not only the DelPhi executable and sources files, examples and parameter files, but also provides links to third party developed resources either utilizing DelPhi or providing plugins for DelPhi. In addition, the users and developers are offered a forum to share ideas, resolve issues, report bugs and seek help with respect to the DelPhi package. The resource is available free of charge for academic users from URL: http://compbio.clemson.edu/DelPhi.php.

  15. Ion source

    International Nuclear Information System (INIS)

    1979-01-01

    The ion source comprises a cylindrically shaped chamber with a longitudinal outlet slot formed therein and two uniform anode wires which extend along the length of the chamber in the middle region thereof and which are symmetrically introduced with respect to the length axis of the chamber and the outlet groove, characterised in that at each outer end of the outlet groove at a nearly null potential or direct potential is introduced a mask, whereby the lowest distance between the inner and outer ends of the mask is equivalent to the breadth of the ion beam emitted from the source. (G.C.)

  16. del alcoholismo

    Directory of Open Access Journals (Sweden)

    Rodrigo Arias Duque

    2005-01-01

    Full Text Available Desde el punto de vista farmacológico, es importante comprender qué es el alcohol y cómo actúa en el organismo. No existe una causa simple, sino una interacción complicada de factores neuroquímicos, fisiológicos, psicológicos y sociales que originan y desarrollan esta grave enfermedad fármaco-dependiente. La acción psicofisiológica y farmacodinámica del alcohol es fundamentalmente depresiva, por la reducción de la transmisión sináptica en el sistema nervioso humano. Es un hecho conocido que el consumo excesivo de alcohol causa una disfunción aguda y crónica del cerebro, produciendo trastornos en el sistema nervioso central, presentando alteraciones en la memoria y en las funciones intelectuales como cálculo, comprensión y aprendizaje. A nivel hepático tiene lugar, en su mayoría, el metabolismo del alcohol, produciéndose un hígado graso alcohólico, aumentando el tamaño, terminando en necrosis e inflamación grave del hígado; esto se llama hepatitis alcohólica, y si se sigue consumiendo alcohol se desarrollará la cirrosis. El alcohol también ha estado relacionado con alteraciones del miocardio; se ha constatado en animales de experimentación sanos que tanto la velocidad de contracción del músculo cardiaco y su máxima tensión disminuyen en presencia del alcohol, como consecuencia, la fuerza de cada contracción y el aumento de presión en el ventrículo izquierdo son menores, perdiendo eficacia el corazón como bomba.

  17. Ion channeling

    International Nuclear Information System (INIS)

    Erramli, H.; Blondiaux, G.

    1994-01-01

    Channeling phenomenon was predicted, many years ago, by stark. The first channeling experiments were performed in 1963 by Davies and his coworkers. Parallely Robinson and Oen have investigated this process by simulating trajectories of ions in monocrystals. This technique has been combined with many methods like Rutherford Backscattering Spectrometry (R.B.S.), Particles Induced X-rays Emission (P.I.X.E) and online Nuclear Reaction (N.R.A.) to localize trace elements in the crystal or to determine crystalline quality. To use channeling for material characterization we need data about the stopping power of the incident particle in the channeled direction. The ratios of channeled to random stopping powers of silicon for irradiation in the direction have been investigated and compared to the available theoretical results. We describe few applications of ion channeling in the field of materials characterization. Special attention is given to ion channeling combined with Charged Particle Activation Analysis (C.P.A.A.) for studying the behaviour of oxygen atoms in Czochralski silicon lattices under the influence of internal gettering and in different gaseous atmospheres. Association between ion channeling and C.P.A.A was also utilised for studying the influence of the growing conditions on concentration and position of carbon atoms at trace levels in the MOVPE Ga sub (1-x) Al sub x lattice. 6 figs., 1 tab., 32 refs. (author)

  18. Ammonium ion interaction with conditioned natural zeolite with silver and its effect on the disinfection of polluted water in front of a consortium of gram (+) and gram (-) microorganisms; Interaccion del ion amonio con zeolita natural acondicionada con plata y su efecto sobre la desinfeccion de agua contaminada frente a un consorcio de microorganismos gram (+) y gram (-)

    Energy Technology Data Exchange (ETDEWEB)

    Gonzaga G, V. E.

    2013-07-01

    Clinoptilolite zeolite material is a relative abundance in Mexico, which has ion exchange properties, therefore, has the ability to retain metal ions giving it an application in the process of disinfecting of water contaminated with pathogenic microorganisms. In this research, we conducted a study of disinfection of water contaminated with a microbial consortium, from a zeolite rock clinoptilolite from a deposit located in the State of Guerrero. Initially, the zeolite prepared by the grinding and sieving, for conditioning with NaCl and subsequently with AgNO{sub 3}, finally to be characterized using the techniques of scanning electron microscopy and X-ray diffraction. Tests using columns packed with zeolite material, the effect of zeolite bactericidal conditioned with silver (ZGAg) against a microbial consortium consisting of Escherichia coli and Sthapyloccocus aureus in aqueous solution in the presence of ammonium ions used to increase the ion exchange with zeolite fitted with silver. To describe curves disinfecting a continuous flow system is adapted Gu pta model, which describes the kinetics and equilibrium adsorption process, considering the microorganisms as the adsorbate and the sanitizing agent (conditioned with silver zeolite) as the adsorbent. Characterization results show that in the scanning electron microscopy (Sem), no changes were obtained on the morphology of typical clinoptilolite crystals before and after that was modified with sodium and then with silver, it is worth mentioning however that fitted with silver zeolite (ZGAg), small particles are seen on the zeolite material which when analyzed by energy dispersive spectroscopy (EDS), we found a high concentration of Ag +. The disinfection period is increased as the concentration increased ammonium ions, this behavior is attributed to the ion exchange that occurs between the ammonium ions and silver ions. A lower percentage of inactivation is due, therefore, to a lesser amount of money available to

  19. Culturas del Mundo

    DEFF Research Database (Denmark)

    Benwell, Ann Fenger; Costa, Alberto; Waehle, Espen

    2006-01-01

    ’Culturas del mundo. Colecciones del Museo Nacional de Dinamarca’ with Ann Fenger Benwell in Culturas del Mundo. Colecciones del Museo Nacional de Dinamarca, ed. Silvia Sauquet, Fundación "la Caixa", Barcelona 2006, pp. 31-39......’Culturas del mundo. Colecciones del Museo Nacional de Dinamarca’ with Ann Fenger Benwell in Culturas del Mundo. Colecciones del Museo Nacional de Dinamarca, ed. Silvia Sauquet, Fundación "la Caixa", Barcelona 2006, pp. 31-39...

  20. Determination of the extractive capacity of para-tert butyl calix[8]arene octa-phosphinoylated towards uranyl ions from an aqueous-acidic-salty medium; Determinacion de la capacidad extractiva del p-ter-butilocalix[8]areno octa-fosfinoilado hacia iones uranilo de un medio acuo-acido salino

    Energy Technology Data Exchange (ETDEWEB)

    Serrano V, E. C.

    2011-07-01

    The extraction properties of octa-phosphinoylated para-tert butyl calix[8]arene (prepared in the laboratory) in chloroform towards uranyl ions from an aqueous-acidic-salty medium (HNO{sub 3}-3.5 NaNO{sub 3}) containing uranyl nitrate salt, was investigated. Two spectroscopic techniques UV/Vis and Luminescence were used for this study. The latter permitted analyze the fluorescence from the uranyl ions influenced by the surrounding medium. Both permitted to learn about the power of this calixarene as extractant towards the mentioned ions. Its extraction ability or capability using this calixarene at 5.91 x 10{sup -4} M towards the uranyl ions was 400% as determined by UV/Vis while fluorescence revealed 100% of uranyl ion extraction. A closed analysis of the results obtained by using these techniques revealed that the stoichiometry of the main extracted species was 1calixarene:2 uranyl ions. The loading capacity of the calixarene ligand towards the uranyl ions was also investigated using both techniques. UV/Vis resulted to be inadequate for quantifying exactly the loading capacity of the calixarene whereas luminescence was excellent indeed, using a 5.91 x 10{sup -4} M calixarene concentration, its loading capacity was 0.157 M of free uranyl ions from 0.161 M of uranyl ions present in the aqueous-acidic-salty medium. The extracts from the ability and capacity studies were concentrated to dryness, purified and the dried extracts were analyzed by infrared and neutron activation analysis. By these techniques it was demonstrated that during the extraction of the uranyl ions by the calixarene ligand they form thermodynamically and kinetically stable complexes, since in the solid state, the 1:2, calixarene; uranyl ions stoichiometry was kept with the minimum formula: (UO{sub 2}){sub 2}B{sub 8}bL{sup 8}(NO{sub 3}){sub 4}(H{sub 2}O){sub 4}CHCl{sub 3}(CH{sub 3}OH){sub 3} the methanol molecules come from its purification. It is proposed that B{sub 8}bL{sup 8} calixarene in

  1. ION VATAMANU

    Directory of Open Access Journals (Sweden)

    l. Povar

    2012-12-01

    Full Text Available Ion Vatamanu was a chemist, writer and public figure. He was equally passionate about both his chosen fields of activity: chemistry and poetry. Chemistry, with its perfect equilibrium of logic and precision, provided inspiration for lyrical creativity, whereas poetry writing enlivened his imagination and passion for chemistry. He loved his parents. He adored his wife Elena, whom he often gifted a sea of flowers. He loved his daughters Mihaela, Mariana, and Leontina. He loved life, and he loved people.

  2. Ion source

    International Nuclear Information System (INIS)

    Saito, Fusao; Okuyama, Toshihisa; Suzuki, Yasuo.

    1996-01-01

    In a negative ion source having magnetic filters, bisecting magnetic fields are formed using electromagnets disposed at the outside of a plasma source. The position of the electromagnets is made adjustable and removable to optimize a negative ion generation efficiency. Further, a plurality of electromagnets are disposed in longitudinal direction of the plasma source, and the intensity of the magnetic fields of the filters in the longitudinal direction is made adjustable to control a beam distribution. Since uniform magnetic fields which bisect the plasma source can be formed by the electromagnets, and magnetomotive force of the electromagnets can be increased easily compared with that of permanent magnets, the magnetomotive force is changed to obtain appropriate filter magnetic fields easily. Then, optimum magnetic fields corresponding to the state of source plasmas can be generated by the control of the power source of the electromagnets, which also increases the negative ion drawing current density, thereby enabling to reduce the drawing area and size of the plasma source. (N.H.)

  3. Ion Beam Extraction by Discrete Ion Focusing

    DEFF Research Database (Denmark)

    2010-01-01

    An apparatus (900) and methods are disclosed for ion beam extraction. In an implementation, the apparatus includes a plasma source (or plasma) (802) and an ion extractor (804). The plasma source is adapted to generate ions and the ion extractor is immersed in the plasma source to extract a fraction...... of the generated ions. The ion extractor is surrounded by a space charge (810) formed at least in part by the extracted ions. The ion extractor includes a biased electrode (806) forming an interface with an insulator (808). The interface is customized to form a strongly curved potential distribution (812......) in the space-charge surrounding the ion extractor. The strongly curved potential distribution focuses the extracted ions towards an opening (814) on a surface of the biased electrode thereby resulting in an ion beam....

  4. Influencia del tiempo de hidrólisis en la obtención de película híbrida con adición de iones cerio para la protección de aceros galvanizados

    Directory of Open Access Journals (Sweden)

    Sandra R. Kuns

    2013-01-01

    Full Text Available Las películas hibridas actúan como una barrera entre el substrato y el medio, reduciendo la velocidad de entrada del agua, electrolito, oxígeno y la penetración deiones agresivos hasta el metal, disminuyendo la velocidad de corrosión del substrato. Los principales factores que influyen en la resistencia a la corrosión de las películas híbridas son: el tiempo de curado, la concentración del baño, el pH de la solución de hidrólisis y el tiempo de hidrólisis. En este trabajo, se realizaron las pruebas con cuatro diferentes tiempos de hidrólisis (1, 3, 24 y 48 horas, el acero galvanizado fue revestido con una película híbrida obtenida a partir de un sol constituido por los precursores alcohoxidos 3-(trimetoxisililpropil metacrilato (TMSPMA y Tetraetoxisilano (TEOS con adición de nitrato de cerio [0,01 M]. La caracterización de las películas fue realizada por MEB, perfilometria, ángulo de contacto, polarización y espectroscopia de impedancia electroquímica. Los resultados muestran que el tiempo de hidrólisis interfiere en la obtención de la película híbrida y consecuentemente en las propiedades protectoras de la película.

  5. Heavy ions

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit

    2002-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  6. Heavy ions

    CERN Multimedia

    CERN. Geneva; Antinori, Federico

    2001-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  7. ION GUN

    Science.gov (United States)

    Dandl, R.A.

    1961-10-24

    An ion gun is described for the production of an electrically neutral ionized plasma. The ion gun comprises an anode and a cathode mounted in concentric relationship with a narrow annulus between. The facing surfaces of the rear portions of the anode and cathode are recessed to form an annular manifold. Positioned within this manifold is an annular intermediate electrode aligned with the an nulus between the anode and cathode. Gas is fed to the manifold and an arc discharge is established between the anode and cathode. The gas is then withdrawn from the manifold through the annulus between the anode and cathode by a pressure differential. The gas is then ionized by the arc discharge across the annulus. The ionized gas is withdrawn from the annulus by the combined effects of the pressure differential and a collimating magnetic field. In a 3000 gauss magnetic field, an arc voltage of 1800 volts, and an arc current of 0.2 amp, a plasma of about 3 x 10/sup 11/ particles/cc is obtained. (AEC)

  8. Ion beam monitoring

    International Nuclear Information System (INIS)

    McKinney, C.R.

    1980-01-01

    An ion beam analyzer is specified, having an ion source for generating ions of a sample to be analyzed, means for extracting the sample ions, means for focusing the sample ions into a beam, separation means positioned along the ion beam for selectively deflecting species of ions, and means for detecting the selected species of ions. According to the specification, the analyzer further comprises (a) means for disabling at least a portion of the separation means, such that the ion beam from the source remains undeflected; (b) means located along the path of the undeflected ion beam for sensing the sample ions; and (c) enabling means responsive to the sensing means for automatically re-enabling the separation means when the sample ions reach a predetermined intensity level. (author)

  9. Ion funnel ion trap and process

    Science.gov (United States)

    Belov, Mikhail E [Richland, WA; Ibrahim, Yehia M [Richland, WA; Clowers, Biran H [West Richland, WA; Prior, David C [Hermiston, OR; Smith, Richard D [Richland, WA

    2011-02-15

    An ion funnel trap is described that includes a inlet portion, a trapping portion, and a outlet portion that couples, in normal operation, with an ion funnel. The ion trap operates efficiently at a pressure of .about.1 Torr and provides for: 1) removal of low mass-to-charge (m/z) ion species, 2) ion accumulation efficiency of up to 80%, 3) charge capacity of .about.10,000,000 elementary charges, 4) ion ejection time of 40 to 200 .mu.s, and 5) optimized variable ion accumulation times. Ion accumulation with low concentration peptide mixtures has shown an increase in analyte signal-to-noise ratios (SNR) of a factor of 30, and a greater than 10-fold improvement in SNR for multiply charged analytes.

  10. F center-molecular ion couples in alkali halides: Magneto-optics study (part two). Spin lattice relaxation time and electron spin memory; Studi di magnetoottica sulla coppia centro F-ione molecolare negli alogenuri alcalini: Parte 2. Misura del tempo di rilassamento spin-reticolo e della memoria di spin dell`elettrone nel ciclo ottico

    Energy Technology Data Exchange (ETDEWEB)

    Baldacchini, G.; Botti, S.; Grassano, U.M.; Luty, F.

    1991-10-01

    The spin-lattice relaxation time in the ground state, T/sub 1/, and the spin-mixing parameter during the optical cycle, epsilon, were measured in FH(OH) and FH(CN) centers in various alkali halides (KCl, KBr, KI, CsCl, and CsBr). For a close comparison, all experiments were performed before and after the optical association of the F center and molecular ion. T/sub 1/ becomes shorter before and still more after aggregation with respect to the values measured in the pure crystal, especially at very low magnetic fields. Epsilon decreases a little in crystals doped with OH-, while it increases a lot in crystals doped with CN-. Part of these results can be interpreted within the actual knowledge of the F-center physics. Part have been used to shed some light on the various unknown aspects of the energy transfer between the excited F-center and the molecular ion.

  11. Behaviour of direct and delayed fast ion losses during NBI on TJ-II; Comportamiento de las perdidas instantaneas y retardadas en la inyeccion de neutros del TJ-II

    Energy Technology Data Exchange (ETDEWEB)

    Guasp, J.; Liniers, M.

    1995-07-01

    The dependence with density and beam energy of the different kind of fast ion losses, direct and delayed, during tangential balanced NBI injection in TJ-II helical axis stellarator has been analysed. Direct losses increase with energy and a strong difference between the two injection directions appears, are produced by passing particles that loss confinement in a few {mu}sec and the influence of birth profiles produces an increase with density. Delayed losses are very well separated in time from direct ones, are produced by particles experimenting pitch angle scattering and, most o them, correspond to trapped particles. Are much less important than the direct ones (about 1/3), decrease slowly with energy and, with C X, increase with density (an effect of initial profile). The absorption is rather independent of energy with low values at low density in reason of high shine through and C X losses, but recovers quickly with the density increase. (Author) 4 refs.

  12. del cambio

    Directory of Open Access Journals (Sweden)

    Alejandro Canales

    2006-01-01

    Full Text Available El artículo analiza las propuestas y los compromisos en materia de cobertura y de financiamiento en el periodo 2000-2006. En particular, revisa las modificaciones y los ajustes de los tres principales documentos en los que se expresaron las iniciativas: el de la Asociación Nacional de Universidades e Instituciones de Educación Superior, el del equipo de la transición y el programa sectorial. Los resultados muestran que las cifras de atención a la demanda educativa e inversión quedaron lejos de las metas autoimpuestas por el gobierno federal y que será necesario realizar mayores esfuerzos para atender tales desafíos.

  13. Resistencia química del hormigón. XI.- Contribución al estudio del sistema: cemento P-450-Y hidratado-agua desionizada

    Directory of Open Access Journals (Sweden)

    Sagrera-Moreno, José Luis

    1981-09-01

    Full Text Available Not available

    En el presente trabajo se estudia el comportamiento de un cemento portland industrial resistente al yeso (P-450-Y con un contenido calculado (Bogue nulo de C3A, del 10,8 % de C4AF y del 81,7 % de C3S + C2S, cuando se somete a la acción del agua desionizada (y de otras disoluciones agresivas; éstas serán objeto de otras publicaciones que atraviesa un lecho granulado fabricado con dicho cemento una vez hidratado y curado a edades distintas, determinando: a La evolución del contenido de los iones Ca (II y SO4 (II de las diversas fracciones recogidas del agua desionizada que ha atravesado el lecho de cemento, así como la del pH y de la conductividad. b La variación del contenido de los iones mencionados, que se encuentran formando compuestos, en el cemento del lecho antes y después de ser sometido a la acción del agua desionizada. c Las modificaciones estructurales experimentadas por los compuestos cristalinos del cemento hidratado del lecho, sometidos a la acción del agua desionizada.

  14. 7 Capillas del Sur

    Directory of Open Access Journals (Sweden)

    Patricio Morgado U.

    1996-05-01

    Full Text Available 7 Capillas del Sur es un extracto de la Tesis de Grado del arquitecto Patricio Morgado Uribe "Reconstrucción de las Iglesias del Sur después del terremoto de 1960 por la Escuela de Arquitectura de la UCV. El caso de Nuestra Señora de La Candelaria".

  15. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 1 covers papers on the advances of gas phase ion chemistry. The book discusses the advances in flow tubes and the measurement of ion-molecule rate coefficients and product distributions; the ion chemistry of the earth's atmosphere; and the classical ion-molecule collision theory. The text also describes statistical methods in reaction dynamics; the state selection by photoion-photoelectron coincidence; and the effects of temperature and pressure in the kinetics of ion-molecule reactions. The energy distribution in the unimolecular decomposition of ions, as well

  16. Microfabricated ion frequency standard

    Science.gov (United States)

    Schwindt, Peter; Biedermann, Grant; Blain, Matthew G.; Stick, Daniel L.; Serkland, Darwin K.; Olsson, III, Roy H.

    2010-12-28

    A microfabricated ion frequency standard (i.e. an ion clock) is disclosed with a permanently-sealed vacuum package containing a source of ytterbium (Yb) ions and an octupole ion trap. The source of Yb ions is a micro-hotplate which generates Yb atoms which are then ionized by a ultraviolet light-emitting diode or a field-emission electron source. The octupole ion trap, which confines the Yb ions, is formed from suspended electrodes on a number of stacked-up substrates. A microwave source excites a ground-state transition frequency of the Yb ions, with a frequency-doubled vertical-external-cavity laser (VECSEL) then exciting the Yb ions up to an excited state to produce fluorescent light which is used to tune the microwave source to the ground-state transition frequency, with the microwave source providing a precise frequency output for the ion clock.

  17. Negative ion sources

    International Nuclear Information System (INIS)

    Ishikawa, Junzo; Takagi, Toshinori

    1983-01-01

    Negative ion sources have been originally developed at the request of tandem electrostatic accelerators, and hundreds of nA to several μA negative ion current has been obtained so far for various elements. Recently, the development of large current hydrogen negative ion sources has been demanded from the standpoint of the heating by neutral particle beam injection in nuclear fusion reactors. On the other hand, the physical properties of negative ions are interesting in the thin film formation using ions. Anyway, it is the present status that the mechanism of negative ion action has not been so fully investigated as positive ions because the history of negative ion sources is short. In this report, the many mechanisms about the generation of negative ions proposed so far are described about negative ion generating mechanism, negative ion source plasma, and negative ion generation on metal surfaces. As a result, negative ion sources are roughly divided into two schemes, plasma extraction and secondary ion extraction, and the former is further classified into the PIG ion source and its variation and Duoplasmatron and its variation; while the latter into reflecting and sputtering types. In the second half of the report, the practical negative ion sources of each scheme are described. If the mechanism of negative ion generation will be investigated more in detail and the development will be continued under the unified know-how as negative ion sources in future, the development of negative ion sources with which large current can be obtained for any element is expected. (Wakatsuki, Y.)

  18. Electron Beam Ion Sources

    CERN Document Server

    Zschornacka, G.; Thorn, A.

    2013-12-16

    Electron beam ion sources (EBISs) are ion sources that work based on the principle of electron impact ionization, allowing the production of very highly charged ions. The ions produced can be extracted as a DC ion beam as well as ion pulses of different time structures. In comparison to most of the other known ion sources, EBISs feature ion beams with very good beam emittances and a low energy spread. Furthermore, EBISs are excellent sources of photons (X-rays, ultraviolet, extreme ultraviolet, visible light) from highly charged ions. This chapter gives an overview of EBIS physics, the principle of operation, and the known technical solutions. Using examples, the performance of EBISs as well as their applications in various fields of basic research, technology and medicine are discussed.

  19. Relación del índice de cristalinidad (IC con la edad y el contenido de iones F y CO3 en muestras de vertebrados fósiles

    Directory of Open Access Journals (Sweden)

    Morales, J.

    2008-06-01

    Full Text Available The crystalline fraction of enamel, dentin and metapodial bone of modern and fossil mammals were studied by X-ray diffraction analysis. The powdered samples were collected from several equids, giraffids, rhinocerotids and proboscideans of Spanish Neogene deposits. Changes in the crystallinity index (CI of apatite are particularly useful to estimate later diagenetic changes in the fossil material. The enamel displays larger CI than dentine and metapodial bone since they have a more dense structure; furthermore there is not a clear relationship between the CI enlargement and the geological age of samples. In addition, the fluorine content increases during the fossilization process and accordingly the parameter CI increases in fossil samples. The carbonate enrichment is not linked to the age of the deposits; however this carbonate increase in enamel, dentine and metapodial bone reduces the CI parameter. The host sediments play an essential role in the crystallinity changes observed in fossil bones; e.g., in the silica sands case, samples display a high CI while in the claystone and chalks case, they display a lower crystallinity index.Se ha determinado el índice de cristalinidad (IC mediante difracción de rayos X de muestras actuales y fósiles pertenecientes a esmalte, dentina y hueso de metápodo de équidos, jiráfidos, rinocerótidos y proboscídeos de diferentes yacimientos neógenos españoles. Con estos valores de la cristalinidad del apatito se estima semicuantitativamente la evolución de los cambios diagenéticos ocurridos en el material óseo fósil. Se ha observado que el esmalte presenta un IC mayor que la dentina y hueso de metápodo, debido a su estructura más compacta. Sin embargo, no hay una correlación clara entre el incremento de la cristalinidad y la edad de las muestras. Además, el contenido de flúor aumenta durante los procesos de fosilización y como consecuencia aumenta el IC en las muestras fósiles. Por otro lado, el

  20. Radioactive Ion Sources

    CERN Document Server

    Stora, T

    2013-01-01

    This chapter provides an overview of the basic requirements for ion sources designed and operated in radioactive ion beam facilities. The facilities where these sources are operated exploit the isotope separation online (ISOL) technique, in which a target is combined with an ion source to maximize the secondary beam intensity and chemical element selectivity. Three main classes of sources are operated, namely surface-type ion sources, arc discharge-type ion sources, and finally radio-frequency-heated plasma-type ion sources.

  1. Ions and light

    CERN Document Server

    Bowers, Michael T

    2013-01-01

    Gas Phase Ion Chemistry, Volume 3: Ions and Light discusses how ions are formed by electron impact, ion-molecule reactions, or electrical discharge. This book discusses the use of light emitted by excited molecules to characterize either the chemistry that formed the excited ion, the structure of the excited ion, or both.Organized into 10 chapters, this volume begins with an overview of the extension of the classical flowing afterglow technique to include infrared and chemiluminescence and laser-induced fluorescence detection. This text then examines the experiments involving molecules that ar

  2. Single Cathode Ion Thruster

    Data.gov (United States)

    National Aeronautics and Space Administration — Objective is to design an electrostatic ion thruster that is more efficient, simpler, and lower cost than the current gridded ion thruster. Initial objective is to...

  3. Applications of decelerated ions

    International Nuclear Information System (INIS)

    Johnson, B.M.

    1985-03-01

    Many facilities whose sole purpose had been to accelerate ion beams are now becoming decelerators as well. The development and current status of accel-decel operations is reviewed here. Applications of decelerated ions in atomic physics experiments are discussed

  4. Characterization of Leucaena (Leucaena leucephala) oil by direct analysis in real time (DART) ion source and gas chromatography; Caracterización del aceite de Leucaena (Leucaena leucocephala) por análisis directo en tiempo real (DART) y cromatografía de gases

    Energy Technology Data Exchange (ETDEWEB)

    Alam, M.; Alandis, N.M.; Sharmin, E.; Ahmad, N.; Alrayes, B.F.; Ali, D.

    2017-07-01

    For the first time, we report the characterization of triacylglycerols and fatty acids in Leucaena (Leucaena leucephala) oil [LUCO], an unexplored nontraditional non-medicinal plant belonging to the family Fabaceae. LUCO was converted to fatty acid methyl esters (FAMEs). We analyzed the triacylglycerols (TAGs) of pure LUCO and their FAMEs by time-of-flight mass spectrometry (TOF-MS) followed by multivariate analysis for discrimination among the FAMEs. Our investigations for the analysis of LUCO samples represent noble features of glycerides. A new type of ion source, coupled with high-resolution TOF-MS was applied for the comprehensive analysis of triacylglycerols. The composition of fatty acid based LUCO oil was studied using Gas Chromatography (GC-FID). The major fatty acid components of LUCO oil are linoleic acid (52.08%) oleic acid (21.26%), palmitic acid (7.91%) and stearic acid (6.01%). A metal analysis in LUCO was done by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The structural elucidation and thermal stability of LUCO were studied by FT-IR, 1H NMR, 13C NMR spectroscopic techniques and TGA-DSC, respectively. We also measured the cytotoxicity of LUCO [Spanish] Se presenta por primera vez la caracterización de triacilgliceroles y ácidos grasos del aceite de Leucaena (Leucaena leucephala) [LUCO], una planta no medicinal, no tradicional y no explorada, perteneciente a la familia Fabaceae. Se analizaron triacilgliceroles (TAGs) de LUCO y sus FAMEs por espectrometría de masas de tiempo de vuelo (TOF-MS) seguido de análisis multivariante para discriminación entre los FAME. Nuestras investigaciones para el análisis de muestras de LUCO presentaron características propias de los glicéridos. Un nuevo tipo de fuente de iones, junto con alta resolución TOF-MS se aplicó para el análisis exhaustivo de triacilgliceroles. La composición de aceite de LUCO basado en ácidos grasos se estudió usando Cromatografía de Gas (GC-FID). Los principales

  5. Kinetic parameters of the phenomenon of light emission thermally stimulated in CaF{sub 2} doped with Tm{sup 3+} ions; Parametros cineticos del fenomeno de emision de luz termicamente estimulada en CaF{sub 2} dopado con iones de Tm{sup 3+}

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, P. R. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Cruz Z, E.; Furetta, C., E-mail: pedro.gonzalez@inin.gob.mx [UNAM, Instituto de Ciencias Nucleares, Apdo. Postal 70-543, 04510 Mexico D. F. (Mexico)

    2015-10-15

    Full text: The characterization of new thermoluminescent materials used in radiation dosimetry, require the determination of kinetic parameters, which are associated with the number and shape of the peaks representing brightness curves. The most important parameters are: energy or depth of the traps (E), the frequency factor (s) and order kinetics (b). These are necessary to predict the stability of the thermoluminescent information saved after the effect of irradiation on the material. In this paper, the results of the determination of kinetic parameters of CaF{sub 2} doped with Tm{sup 3+} ions are presented, after being irradiated with gamma rays of {sup 60}Co. The methods used for the determination of kinetic parameters were: initial growth of thermoluminescent signal, Chen method of type general order and by deconvolution of the brightness curve. The results showed that the brightness curve of CaF{sub 2} has three peaks, the main peak at 491 K and two smaller peaks, one at 431 and another at 573 K. The dosimetric peak (491 K) has general order kinetics. (Author)

  6. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 2 covers the advances in gas phase ion chemistry. The book discusses the stabilities of positive ions from equilibrium gas-phase basicity measurements; the experimental methods used to determine molecular electron affinities, specifically photoelectron spectroscopy, photodetachment spectroscopy, charge transfer, and collisional ionization; and the gas-phase acidity scale. The text also describes the basis of the technique of chemical ionization mass spectrometry; the energetics and mechanisms of unimolecular reactions of positive ions; and the photodissociation

  7. Ion mobility spectrometry

    CERN Document Server

    Eiceman, GA

    2005-01-01

    Key Developments for Faster, More Precise Detection Capabilities Driven by the demand for the rapid and advanced detection of explosives, chemical and biological warfare agents, and narcotics, ion mobility spectrometry (IMS) undergone significant refinements in technology, computational capabilities, and understanding of the principles of gas phase ion chemistry and mobility. Beginning with a thorough discussion of the fundamental theories and physics of ion mobility, Ion Mobility Spectrometry, Second Edition describes the recent advances in instrumentation and newly

  8. Negative Ion Density Fronts

    International Nuclear Information System (INIS)

    Igor Kaganovich

    2000-01-01

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas

  9. Acerca del moho

    Science.gov (United States)

    El moho forma parte del medio ambiente natural. Afuera del hogar, el moho juega un papel en la naturaleza al desintegrar materias organicas tales como las hojas que se han caido o los arboles muertos. El moho puede crecer adentro del hogar cuando las espor

  10. Del bit al qubit

    OpenAIRE

    Torras Font, Josep

    2011-01-01

    Aquest document pretén donar una visió del desenvolupament dels computadors electrònics i dels components que els han fet possibles. Dintre de les opcions de futur en computació, també intenta donar una visió de les bases en que es fonamenta la computació quàntica.

  11. Enhanced ion acoustic fluctuations and ion outflows

    Directory of Open Access Journals (Sweden)

    F. R. E. Forme

    1999-02-01

    Full Text Available A number of observations showing enhanced ion acoustic echoes observed by means of incoherent scatter radars have been reported in the literature. The received power is extremely enhanced by up to 1 or 2 orders of magnitude above usual values, and it is mostly contained in one of the two ion acoustic lines. This spectral asymmetry and the intensity of the received signal cannot be resolved by the standard analysis procedure and often causes its failure. As a result, and in spite of a very clear spectral signature, the analysis is unable to fit the plasma parameters inside the regions of ion acoustic turbulence. We present European Incoherent Scatter radar (EISCAT observations of large ion outflows associated with the simultaneous occurrence of enhanced ion acoustic echoes. The ion fluxes can reach 1014 m-2 s-1 at 800 km altitude. From the very clear spectral signatures of these echoes, a method is presented to extract estimates of the electron temperature and the ion drift within the turbulent regions. It is shown that the electron gas is strongly heated up to 11 000 K. Also electron temperature gradients of about 0.02 K/m exist. Finally, the estimates of the electron temperature and of the ion drift are used to study the possible implications for the plasma transport inside turbulent regions. It is shown that strong electron temperature gradients cause enhancement of the ambipolar electric field and can account for the observed ion outflows.Key words. Ionosphere (auroral ionosphere; ionosphere · magnetosphere interactions; plasma waves and instabilities.

  12. Multicharged ion sources

    International Nuclear Information System (INIS)

    Venikov, N.I.

    1979-01-01

    The main principles of action, beam parameters, basic problems and prospects for development of the available multicharged ion sources for various types of accelerators are considered. Descriptions of three types of Penneng sources (a source with coid cathodes, direct-heated source, and a source with a heated cathode), duoplasmatron, SHP source using electron-cyclotron resonance, electron-ray and laser sources are given. The problems productions for solid substance ions, lithium and beryllium ions in Penning sources, are considered as well as the problem of ion charge growth on passage of accelerated ion/or atom beam through a stripping target [ru

  13. Vacuum Arc Ion Sources

    CERN Document Server

    Brown, I.

    2013-12-16

    The vacuum arc ion source has evolved into a more or less standard laboratory tool for the production of high-current beams of metal ions, and is now used in a number of different embodiments at many laboratories around the world. Applications include primarily ion implantation for material surface modification research, and good performance has been obtained for the injection of high-current beams of heavy-metal ions, in particular uranium, into particle accelerators. As the use of the source has grown, so also have the operational characteristics been improved in a variety of different ways. Here we review the principles, design, and performance of vacuum arc ion sources.

  14. Sindrome del túnel del carpo

    OpenAIRE

    García Parra, Gabriela Cristina; Gómez Eslava, Andrés Fernando; González Artunduaga, Eliana Andrea

    2009-01-01

    El Síndrome del Túnel de Carpo (STC) es un atrapamiento del nervio mediano en el túnel del carpo; es más común entre las mujeres y se considera como una enfermedad ocupacional. Su etiología es diversa, comprendiendo causas locales, regionales y sistémicas. Sin embargo, en la práctica clínica esta se desconoce hasta en el 50% de los casos. Sobre su fisiopatología poco se conoce; se proponen tres teorías para explicarla: la compresión, la insuficiencia microvascular y la teoría vibratoria, las ...

  15. Quantitative ion implantation

    International Nuclear Information System (INIS)

    Gries, W.H.

    1976-06-01

    This is a report of the study of the implantation of heavy ions at medium keV-energies into electrically conducting mono-elemental solids, at ion doses too small to cause significant loss of the implanted ions by resputtering. The study has been undertaken to investigate the possibility of accurate portioning of matter in submicrogram quantities, with some specific applications in mind. The problem is extensively investigated both on a theoretical level and in practice. A mathematical model is developed for calculating the loss of implanted ions by resputtering as a function of the implanted ion dose and the sputtering yield. Numerical data are produced therefrom which permit a good order-of-magnitude estimate of the loss for any ion/solid combination in which the ions are heavier than the solid atoms, and for any ion energy from 10 to 300 keV. The implanted ion dose is measured by integration of the ion beam current, and equipment and techniques are described which make possible the accurate integration of an ion current in an electromagnetic isotope separator. The methods are applied to two sample cases, one being a stable isotope, the other a radioisotope. In both cases independent methods are used to show that the implantation is indeed quantitative, as predicted. At the same time the sample cases are used to demonstrate two possible applications for quantitative ion implantation, viz. firstly for the manufacture of calibration standards for instrumental micromethods of elemental trace analysis in metals, and secondly for the determination of the half-lives of long-lived radioisotopes by a specific activity method. It is concluded that the present study has advanced quantitative ion implantation to the state where it can be successfully applied to the solution of problems in other fields

  16. Algunas aclaraciones acerca del conocimiento del singular.

    Directory of Open Access Journals (Sweden)

    Carlos Llano Cifuentes

    2013-11-01

    Full Text Available Llano tries to explain the main purpose of El Conocimiento del Singular, showing how the individuals about which the book is concerned are basically human individuals: people as decision makers.

  17. Atomic ion clock with two ion traps, and method to transfer ions

    Science.gov (United States)

    Prestage, John D. (Inventor); Chung, Sang K. (Inventor)

    2011-01-01

    An atomic ion clock with a first ion trap and a second ion trap, where the second ion trap is of higher order than the first ion trap. In one embodiment, ions may be shuttled back and forth from one ion trap to the other by application of voltage ramps to the electrodes in the ion traps, where microwave interrogation takes place when the ions are in the second ion trap, and fluorescence is induced and measured when the ions are in the first ion trap. In one embodiment, the RF voltages applied to the second ion trap to contain the ions are at a higher frequency than that applied to the first ion trap. Other embodiments are described and claimed.

  18. SULL'ORIGINE DEL ROMBO DEL TUONO

    Directory of Open Access Journals (Sweden)

    g. zanotelli

    1951-06-01

    Full Text Available Si interpretano le cause fisiche di due fra le più singolari caratteristichedel rombo del tuono, e cioè la sua lunga persistenza ed iltimbro eminentemente ricco di suoni bassi. Per quanto altri autoriavessero in passato localizzato l'origine di questi fatti in svariate edoccasionali circostanze di ambiente, si è potuto dimostrare teoricamentenel presente lavoro come gli ammassi di goccioline di acqua checostituiscono le formazioni nuvolose esercitino una riflessione selettivasulle onde sonore incidenti: precisamente tale riflessione avviene inmisura apprezzabile solo per le componenti della perturbazione sonora,originata dallo scoppio del fulmine, di frequenza inferiore acerte due frequenze di taglio, proprie, l'ima del fenomeno di alternacondensazione ed evaporazione delle goccioline sotto l'azione delle variazionidi pressione sonora, e l'altra del parziale trascinamento dellegoccioline stesse nel moto dell'onda sonora per effetto della viscositàdell'aria. In base a questi risultati e tenuta anche presente la eventualitàdi più riflessioni successive si giustifica come, a causa dellabassa velocità del suono nell'atmosfera e della relativamente grandedistanza delle nubi, il rumore del tuono possa persistere a lungo; sipuò inoltre prevedere che il timbro sonoro debba farsi sempre piùcupo, via via che il rimbombo si prolunga.

  19. Ion photon emission microscope

    Science.gov (United States)

    Doyle, Barney L.

    2003-04-22

    An ion beam analysis system that creates microscopic multidimensional image maps of the effects of high energy ions from an unfocussed source upon a sample by correlating the exact entry point of an ion into a sample by projection imaging of the ion-induced photons emitted at that point with a signal from a detector that measures the interaction of that ion within the sample. The emitted photons are collected in the lens system of a conventional optical microscope, and projected on the image plane of a high resolution single photon position sensitive detector. Position signals from this photon detector are then correlated in time with electrical effects, including the malfunction of digital circuits, detected within the sample that were caused by the individual ion that created these photons initially.

  20. Ion implantation in metals

    International Nuclear Information System (INIS)

    Vook, F.L.

    1977-02-01

    The application of ion beams to metals is rapidly emerging as a promising area of research and technology. This report briefly describes some of the recent advances in the modification and study of the basic properties of metals by ion implantation techniques. Most of the research discussed illustrates some of the new and exciting applications of ion beams to metals which are under active investigation at Sandia Laboratories, Albuquerque

  1. Ion Trap Quantum Computing

    Science.gov (United States)

    2011-12-01

    stored ions,” Adv. Atom Mol. Phys., vol. Volume 3, pp. 53–72 1968. [48] P. H. Dawson, Quadrupole Mass Spectometry and Its Applications, Melville, NY... DATE December 2011 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Ion trap Quantum Computing 5. FUNDING NUMBERS 6...researcher [30] that introduced the concept of ion traps in the 1950s. His experiments focused on separating atoms with different masses in order to

  2. Neutron ion temperature measurement

    International Nuclear Information System (INIS)

    Strachan, J.D.; Hendel, H.W.; Lovberg, J.; Nieschmidt, E.B.

    1986-11-01

    One important use of fusion product diagnostics is in the determination of the deuterium ion temperature from the magnitude of the 2.5 MeV d(d,n) 3 He neutron emission. The detectors, calibration methods, and limitations of this technique are reviewed here with emphasis on procedures used at PPPL. In most tokamaks, the ion temperature deduced from neutrons is in reasonable agreement with the ion temperature deduced by other techniques

  3. Lithium-ion batteries

    CERN Document Server

    Yoshio, Masaki; Kozawa, Akiya

    2010-01-01

    This book is a compilation of up-to-date information relative to Li-Ion technology. It provides the reader with a single source covering all important aspects of Li-Ion battery operations. It fills the gap between the old original Li-Ion technology and present state of the technology that has developed into a high state of practice. The book is designed to provide a single source for an up-to-date description of the technology associated with the Li-Ion battery industry. It will be useful to researchers interested in energy conversion for the direct conversion of chemical energy into electrica

  4. Dynamic ion implantation

    International Nuclear Information System (INIS)

    Oppenheim, I.F.C.

    1988-01-01

    The Dynamic Ion Implantation Technique consists of ion implantation of a film during the film-deposition process. This technique was investigated theoretically and experimentally with ions whose incident energy is of the order of a few times 100 keV. It was found to be a viable alternative low-temperature method for the preparation of thick zirconium nitride films (∼1 μm) with good mechanical properties. Theoretical modeling of the processes involved during dynamic ion implantation lead to analytical expressions for the ions' depth-profile distributions. Numerical evaluations of these equations indicated that the depth distributions of dynamically implanted ions are in general more uniform than those predicted by the model for ions implanted by more conventional techniques. Mechanical properties of stoichiometric RF sputter-deposited zirconium nitride films post implanted with krypton and rubidium ions were investigated. Scratch-adhesion critical load and Vickers microhardness of samples implanted with doses varying from 1 x 10 15 to 5 x 10 16 ions/cm 2 and energies ranging from 300 to 500 keV were studied. In general, best mechanical properties were observed for 300- keV krypton implantations

  5. Correlation ion mobility spectroscopy

    Science.gov (United States)

    Pfeifer, Kent B [Los Lunas, NM; Rohde, Steven B [Corrales, NM

    2008-08-26

    Correlation ion mobility spectrometry (CIMS) uses gating modulation and correlation signal processing to improve IMS instrument performance. Closely spaced ion peaks can be resolved by adding discriminating codes to the gate and matched filtering for the received ion current signal, thereby improving sensitivity and resolution of an ion mobility spectrometer. CIMS can be used to improve the signal-to-noise ratio even for transient chemical samples. CIMS is especially advantageous for small geometry IMS drift tubes that can otherwise have poor resolution due to their small size.

  6. Doppler ion program description

    International Nuclear Information System (INIS)

    Henline, P.

    1980-12-01

    The Doppler spectrometer is a conventional Czerny-Turner grating spectrometer with a 1024 channel multiple detector. Light is dispersed across the detector, and its output yields a spectrum covering approximately 200 A. The width of the spectral peak is directly proportional to the temperature of the emitting ions, and determination of the impurity ion temperature allows one to infer the plasma ion temperature. The Doppler ion software system developed at General Atomic uses a TRACOR Northern 1710-31 and an LSI-11/2. The exact configuration of Doublet III is different from TRACOR Northern systems at other facilities

  7. Teleopio del Pueblo

    Directory of Open Access Journals (Sweden)

    Paul Little

    2015-01-01

    Full Text Available Temas trascendentes de este número son Historia del Nuevo Periodismo, Derecho Social a la información y La televisión: Teleopio del pueblo. Se agregan otros como la investigación en el trabajo popular, LA mujer rural , El audiovisual en el Ecuador y Cambios en la comunicación a raíz del NOMIC.

  8. Historia del Nuevo Periodismo

    Directory of Open Access Journals (Sweden)

    María Luisa Rodríguez

    2015-01-01

    Full Text Available Temas trascendentes de este número son Historia del Nuevo Periodismo, Derecho Social a la información y La televisión: Teleopio del pueblo. Se agregan otros como la investigación en el trabajo popular, LA mujer rural , El audiovisual en el Ecuador y Cambios en la comunicación a raíz del NOMIC.

  9. Carta del editor

    Directory of Open Access Journals (Sweden)

    Juan Braun

    2015-01-01

    Full Text Available Temas trascendentes de este número son Historia del Nuevo Periodismo, Derecho Social a la información y La televisión: Teleopio del pueblo. Se agregan otros como la investigación en el trabajo popular, LA mujer rural , El audiovisual en el Ecuador y Cambios en la comunicación a raíz del NOMIC.

  10. Psicodrama del duelo.

    OpenAIRE

    José Antonio Espina Barrio; Marisol Filgueira Bouza

    1997-01-01

    La pérdida de rituales agrava y alarga la reacción del duelo. Se define el Psicodrama Antropológico y su intervención en el proceso del duelo. El Psicodrama Focal del Duelo es una psicoterapia breve centrada en el proceso de Duelo. Se comentan varios casos y resultados. Se concluye con un programa sencillo para el duelo en Atención Primaria.

  11. Fractura triple del complejo suspensorio del hombro

    Directory of Open Access Journals (Sweden)

    Eraclio Delgado Rifá

    2015-06-01

    Full Text Available El complejo suspensorio del hombro es una estructura sumamente importante, compuesta por un anillo de huesos y tejidos blandos. Las lesiones aisladas de este complejo anatómico son frecuentes y no afectan su estabilidad. La interrupción doble conduce a la inestabilidad de esta estructura y usualmente requiere tratamiento quirúrgico. La triple interrupción, por su parte, es sumamente rara y es encontrada en casos de trauma de alta energía a menudo en asociación con otras lesiones. Se presenta una triple lesión del complejo suspensorio del hombro en un paciente de 46 años de edad, con una fractura de la glenoides, del acromion tipo III de Kuhn y de la coracoides tipo II de Ogawa. En este caso, la fractura del acromion fue tratada con fijación percutánea con alambres de Kirschner, por tener asociado lesiones de partes blandas que contraindicaron la reducción abierta. La fractura de la glenoides y de la apófisis coracoides fueron tratadas conservadoramente. Después de 6 meses de evolución, el paciente tuvo un resultado funcional aceptable, con una abducción de 90 grados, los 30 grados de rotación externa y 70 de rotación interna, además asintomático y consolidación de todas las fracturas. A pesar de ser catalogada de una lesión grave del cinturón escapular y estar asociada a otras lesiones se obtuvo un resultado satisfactorio al final del tratamiento.

  12. del queso edam

    Directory of Open Access Journals (Sweden)

    JUAN FELIPE OSORIO TOBÓN

    2005-01-01

    Full Text Available El comportamiento reológico y textural del queso Edam fue obtenido mediante pruebas de relajación, creep y análisis de perfil de textura (TPA. Los resultados mostraron que el queso es un material de naturaleza viscoelástica, donde los modelos generalizados de Kelvin y Maxwell resultaron ideales para predecir el comportamiento reológico del producto. Los parámetros texturales tales como la dureza, cohesividad, adhesividad y masticabilidad son dependientes del tiempo de maduración pero no la resortabilidad del producto.

  13. High current ion sources

    International Nuclear Information System (INIS)

    Brown, I.G.

    1989-06-01

    The concept of high current ion source is both relative and evolutionary. Within the domain of one particular kind of ion source technology a current of microamperers might be 'high', while in another area a current of 10 Amperes could 'low'. Even within the domain of a single ion source type, what is considered high current performance today is routinely eclipsed by better performance and higher current output within a short period of time. Within their fields of application, there is a large number of kinds of ion sources that can justifiably be called high current. Thus, as a very limited example only, PIGs, Freemen sources, ECR sources, duoplasmatrons, field emission sources, and a great many more all have their high current variants. High current ion beams of gaseous and metallic species can be generated in a number of different ways. Ion sources of the kind developed at various laboratories around the world for the production of intense neutral beams for controlled fusion experiments are used to form large area proton deuteron beams of may tens of Amperes, and this technology can be used for other applications also. There has been significant progress in recent years in the use of microwave ion sources for high current ion beam generation, and this method is likely to find wide application in various different field application. Finally, high current beams of metal ions can be produced using metal vapor vacuum arc ion source technology. After a brief consideration of high current ion source design concepts, these three particular methods are reviewed in this paper

  14. Caracterización del receptor benzodiacepínico periférico en tejidos de rata y humanos

    OpenAIRE

    Camins Espuny, Antoni

    1992-01-01

    1) INTRODUCCIÓNLas benzodiacepinas son unos fármacos ampliamente usados en nuestros días para el tratamiento clínico de síntomas relacionados con la ansiedad, pero estos fármacos producen por otro lados efectos miorrelajantes, anticonvulsivantes e hipnóticos. Las benzodiacepinas median estos efectos a través del receptor benzodiacepínico central el cual está unido a receptor del GABA y del ionóforo del cloro.Aunque estos efectos farmacológicos están mediados a través del receptor benzodiacep...

  15. Riesgos laborales en trabajadores del sector informal del Cauca, Colombia

    OpenAIRE

    Augusto Muñoz-Caicedo; Pilar Mirely Chois-Lenis

    2014-01-01

    Antecedentes. Un estudio a nivel nacional permitió establecer los riesgos a los cuales estaban expuestos los trabajadores del sector informal del comercio. Sin embargo, no fue incluido el Departamento del Cauca. Objetivo. Describirlos riesgos laborales de las personas ocupadas en el sector informal del comercio, en cinco municipios del departamento del Cauca, durante el 2011. Materiales y métodos. Estudio descriptivo, transversal, desarrollado con 223 sujetos a quienes se les aplicó una encue...

  16. Propiedades prooxidantes del camu camu (Myrciaria dubia

    Directory of Open Access Journals (Sweden)

    Henry Guija

    2005-12-01

    Full Text Available Objetivo: Determinar el efecto del ion férrico sobre las propiedades prooxidantes del camu camu (Myrciaria dubia. Diseño: Estudio analítico, experimental, prospectivo y longitudinal. Materiales y Métodos: Se ha evaluado las propiedades prooxidantes del camu camu (Myrciaria dubia, fruto caracterizado por tener un elevado contenido de vitamina C, frente a Fe(III, etilendiamino tetraacético (EDTA, tiourea y manitol. Resultados: El camu camu en presencia de Fe-III en tampón fosfato a pH 7,4 incrementó notablemente la generación de radicales libres a través de una cinética de saturación, efecto que fue dependiente de la concentración del metal. La presencia de tiourea o manitol, compuestos de conocida acción antioxidante, inhibieron la formación de radicales libres, en cambio el EDTA lo incrementó. Conclusión: El camu camu incrementa la generación de radicales libres en presencia de Fe(III y EDTA.

  17. Where do ions solvate?

    Indian Academy of Sciences (India)

    Abstract. We study a simple model of ionic solvation inside a water cluster. The cluster is modeled as a spherical dielectric continuum. It is found that unpolarizable ions always prefer the bulk solvation. On the other hand, for polarizable ions, there exists a critical value of polarization above which surface solvation becomes ...

  18. Ion-beam technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, G.R. [Argonne National Lab., IL (United States)

    1993-01-01

    This compilation of figures and diagrams reviews processes for depositing diamond/diamond-like carbon films. Processes addressed are chemical vapor deposition (HFCVD, PACVD, etc.), plasma vapor deposition (plasma sputtering, ion beam sputtering, evaporation, etc.), low-energy ion implantation, and hybrid processes (biased sputtering, IBAD, biased HFCVD, etc.). The tribological performance of coatings produced by different means is discussed.

  19. Quadrupole Ion Traps

    Indian Academy of Sciences (India)

    elimination of transit-time broadening making it possible to do precision spectroscopic measurements on these ions. Several important experiments with single electron or ion have been undertaken to address problems related to basic physics, such as the measurement of the electron radius, precision measurements of ...

  20. Ion implantation in ices

    International Nuclear Information System (INIS)

    Strazzulla, G.; Baratta, G.A.; Palumbo, M.E.; Satorre, M.A.

    2000-01-01

    We have studied, by in situ infrared spectroscopy, some effects due to ion implantation in frozen ices. In particular mixtures containing C, N and O atoms (e.g., N 2 :H 2 O:CH 4 ) have been irradiated with unreactive (noble gases) ions: the resulting alteration of the frozen sample induces the formation of other molecules (e.g., CO 2 , R- - -OCN, CO and HCN) and of a refractory organic residue. Similar products are formed when mixtures containing only C and O atoms (e.g., H 2 O:CH 4 ) are irradiated with N ions, i.e. molecular species that include the projectile are formed. These results are important, in particular for their applications to planetary physics. In planetary environments ice thickness is usually much larger than the penetration depth of the relevant ion populations (solar wind ions, magnetospheric particles, etc.) and ion implantation phenomena are expected. Our results indicate that some molecular species observed on icy planetary surfaces could not be native of that object but formed by ion irradiation and/or by implantation of reactive ions

  1. Accelerators for heavy ions

    International Nuclear Information System (INIS)

    Martin, J.A.

    1975-01-01

    The use of heavy ion accelerators in nuclear physics, nuclear chemistry, atomic physics, and in material sciences studies is rapidly increasing. A review is given of the present and developing scene in heavy ion accelerator concepts and technology. The area of applicability of various methods, likely avenues of future development, and the trends of future requirements are discussed. (auth)

  2. Ion beam studies

    International Nuclear Information System (INIS)

    Freeman, J.H.; Chivers, D.J.; Gard, G.A.; Temple, W.

    1977-04-01

    A description of techniques for the production of intense beams of heavy ions is given. A table of recommended operational procedures for most elements is included. The ionisation of boron is considered in some detail because of its particular importance as a dopant for ion implantation. (author)

  3. Cooperativity in ion hydration

    NARCIS (Netherlands)

    Tielrooij, K.J.; Garcia-Araez, N.; Bonn, M.; Bakker, H.J.

    2010-01-01

    Despite prolonged scientific efforts to unravel the effects of ions on the structure and dynamics of water, many open questions remain, in particular concerning the spatial extent of this effect (i.e., the number of water molecules affected) and the origin of ion-specific effects. A combined

  4. Future of ion machines

    International Nuclear Information System (INIS)

    Blaha, A.

    1975-01-01

    On the basis of a systematic arrangement of various types of ion machines according to their purpose, the corresponding characteristic functional parameters of the individual machines are derived. Atomic and nuclear ion machines are not dealt with. The common characteristics of this new type of machines are derived, namely the velocity of the beam, its formation capacity and interaction

  5. Quadrupole Ion Traps

    Indian Academy of Sciences (India)

    electron bound to the gravitational field, the 'geonium atom'. The first atomic hyperfine structure experiment on trapped ions was performed by Dehmelt's group using the stored-ion exchange-collision technique in a Paul trap which paved the way for some of the subsequent experiment for atomic frequency. A single atom at.

  6. Where do ions solvate?

    Indian Academy of Sciences (India)

    We study a simple model of ionic solvation inside a water cluster. The cluster is modeled as a spherical dielectric continuum. It is found that unpolarizable ions always prefer the bulk solvation. On the other hand, for polarizable ions, there exists a critical value of polarization above which surface solvation becomes ...

  7. Ion mobilities and ion-atom interaction potentials

    International Nuclear Information System (INIS)

    Gatland, I.R.

    1982-01-01

    The techniques for measuring the mobilities of ions in gases, relating interaction potentials to mobilities, and determining potentials from experimental mobilities are reviewed. Applications are presented for positive alkali ions and negative halogen ions in inert gases. (Auth.)

  8. Cryogenic surface ion traps

    International Nuclear Information System (INIS)

    Niedermayr, M.

    2015-01-01

    Microfabricated surface traps are a promising architecture to realize a scalable quantum computer based on trapped ions. In principle, hundreds or thousands of surface traps can be located on a single substrate in order to provide large arrays of interacting ions. To this end, trap designs and fabrication methods are required that provide scalable, stable and reproducible ion traps. This work presents a novel surface-trap design developed for cryogenic applications. Intrinsic silicon is used as the substrate material of the traps. The well-developed microfabrication and structuring methods of silicon are utilized to create simple and reproducible traps. The traps were tested and characterized in a cryogenic setup. Ions could be trapped and their life time and motional heating were investigated. Long ion lifetimes of several hours were observed and the measured heating rates were reproducibly low at around 1 phonon per second at a trap frequency of 1 MHz. (author) [de

  9. Molecular ion photofragment spectroscopy

    International Nuclear Information System (INIS)

    Bustamente, S.W.

    1983-11-01

    A new molecular ion photofragment spectrometer is described which features a supersonic molecular beam ion source and a radio frequency octapole ion trap interaction region. This unique combination allows several techniques to be applied to the problem of detecting a photon absorption event of a molecular ion. In particular, it may be possible to obtain low resolution survey spectra of exotic molecular ions by using a direct vibrational predissociation process, or by using other more indirect detection methods. The use of the spectrometer is demonstrated by measuring the lifetime of the O 2 + ( 4 π/sub u/) metastable state which is found to consist of two main components: the 4 π/sub 5/2/ and 4 π/sub -1/2/ spin components having a long lifetime (approx. 129 ms) and the 4 π/sub 3/2/ and 4 π/sub 1/2/ spin components having a short lifetime (approx. 6 ms)

  10. Ion mobility sensor system

    Science.gov (United States)

    Xu, Jun; Watson, David B.; Whitten, William B.

    2013-01-22

    An ion mobility sensor system including an ion mobility spectrometer and a differential mobility spectrometer coupled to the ion mobility spectrometer. The ion mobility spectrometer has a first chamber having first end and a second end extending along a first direction, and a first electrode system that generates a constant electric field parallel to the first direction. The differential mobility spectrometer includes a second chamber having a third end and a fourth end configured such that a fluid may flow in a second direction from the third end to the fourth end, and a second electrode system that generates an asymmetric electric field within an interior of the second chamber. Additionally, the ion mobility spectrometer and the differential mobility spectrometer form an interface region. Also, the first end and the third end are positioned facing one another so that the constant electric field enters the third end and overlaps the fluid flowing in the second direction.

  11. El efecto perverso del simulacro del consumo

    Directory of Open Access Journals (Sweden)

    Paulo De Tarso Riccordi

    2015-01-01

    Full Text Available Los domingos las Redes Globo y S.B.T. retienen entre el 60 y 70% de la audiencia nacional de Brasil. El autor resume la distribución de la pauta publicitaria entre los medios. Los marginados de la economía pueden acceder al consumo a través del simulacro televisivo o de la apropiación violenta. La televisión es uno de los componentes del proceso Deseo-Frustración-Revuelta, que forma parte de la historia urbana contemporánea de Brasil. El acceso casi mágico al producto publicitario, el simulacro del consumo que ofrecen los programas tipo "Silvio Santos" los múltiples sorteos y loterías oficiales y clandestinas, simultáneamente apaciguan y exaltan el deseo de consumir lo inaccesible.

  12. La luz del origen del universo

    Directory of Open Access Journals (Sweden)

    Casas, Alberto

    2015-10-01

    Full Text Available Penzias and Wilson discovered the cosmic microwave background, a luminous echo of the Big Bang, in 1965. The amount of information encoded in this relic of the early universe is truly extraordinary. At present, the most precise data about the origin and structure of the universe comes from the study of this primordial light, the full potential of which has yet to be explored.En 1965 se descubrió el fondo de radiación de microondas, un eco luminoso de la Gran Explosión (Big Bang. La cantidad de información contenida en esta reliquia del universo primitivo es verdaderamente extraordinaria. En la actualidad los datos más precisos sobre el origen y estructura del universo provienen del estudio de esta luz primigenia, que aún no ha sido explorada en todo su potencial.

  13. Displasias del seno

    Directory of Open Access Journals (Sweden)

    Ernesto Andrade Valderrama

    1971-04-01

    Full Text Available En general, las Displasias no se presentan antes de la iniciación del estímulo Gonadal y tienden a desaparecer con el climaterio. Se definen entonces como las afecciones benignas del Seno, de origen endocrino.

  14. Archivo del Duelo

    OpenAIRE

    Ferrera, Tamara

    2010-01-01

    Photos taken from the Archive of Mourning following the March 11 terrorist attacks El Archivo del Duelo. Creación de un archivo etnográfico de los Atentados del 11 de marzo en Madrid. Ministerio de Educación y Ciencia HUM2005-03490.

  15. Il dono del racconto

    DEFF Research Database (Denmark)

    Polito, Paola

    1998-01-01

    'importanza assunta nel romanzo dal piano dell'enunciazione come luogo privilegiato di manifestazione del soggetto quale esperiente una vicenda di maturazione. Il protagonista, qui, non solo si rappresenta in ciò che enuncia e riferisce, ma anche e soprattutto si svela nelle modalità specifiche del proprio discorso...

  16. Cartas del Observatorio N° 2

    OpenAIRE

    Castell, Edmon; Torres Carreño, Guillermo Andrés; Diazgranados, Carlos Nicolás; Mora, Yaneth

    2011-01-01

    El boletín del OAN, "Cartas del Observatorio", es una pieza de comunicación desarrollada entre el Observatorio Astronómico Nacional (OAN) y el Área de Comunicación del SPM. El boletín periódico forma parte de los aportes del SPM al Bicentenario de la Independencia (2010) de Colombia. Este segundo número de Cartas del Observatorio, describe la construcción del edificio, el plan museológico por parte del SPM, una de las piezas importante del OAN, la publicación de la infografía y la partici...

  17. Plasma source ion implantation

    International Nuclear Information System (INIS)

    Conrad, J.R.; Forest, C.

    1986-01-01

    The authors' technique allows the ion implantation to be performed directly within the ion source at higher currents without ion beam extraction and transport. The potential benefits include greatly increased production rates (factors of 10-1000) and the ability to implant non-planar targets without rastering or shadowing. The technique eliminates the ion extractor grid set, beam raster equipment, drift space and target manipulator equipment. The target to be implanted is placed directly within the plasma source and is biased to a large negative potential so that plasma ions gain energy as they accelerate through the potential drop across the sheath that forms at the plasma boundary. Because the sheath surrounds the target on all sides, all surfaces of the target are implanted without the necessity to raster the beam or to rotate the target. The authors have succeeded in implanting nitrogen ions in a silicon target to the depths and concentrations required for surface treatment of materials like stainless steel and titanium alloys. They have performed ESCA measurements of the penetration depth profile of a silicon target that was biased to 30 kV in a nitrogen discharge plasma. Nitrogen ions were implanted to a depth of 700A at a peak concentration of 30% atomic. The measured profile is quite similar to a previously obtained profile in titanium targets with conventional techniques

  18. La crisi del diritto del lavoro

    Directory of Open Access Journals (Sweden)

    Alessandro Garilli

    2012-01-01

    Full Text Available Riassunto - L’Autore ripercorre in chiave critica l’evoluzione delle politiche legislative in materia di lavoro, alla luce dell’attuale fase di crisi economico finanziaria. Nell’esaminare i principali interventi normativi attuati da inizio secolo, l’Autore mette in evidenza le scelte di metodo e gli elementi di continuità che accomunano i vari provvedimenti, individuandoli nell’affannosa ricerca del punto di equilibrio tra flessibilità e garantismo. La riflessione si chiude con alcuni interrogativi sulle ultime linee di riforma del mercato del lavoro e con l’auspicio che, anche al cospetto delle imprescindibili ragioni dell’economia, il diritto del lavoro possa continuare a svolgere il proprio tradizionale ruolo di disciplina di tutela della persona.   Abstract - The author analyzes, with a critically oriented approach, the development of the employment law, in the light of the current economic and financial crisis. In examining the main regulatory measures implemented since the beginning of the century, the author highlights the methodological choices and the elements of continuity that unite the various measures, focusing them in a hard research of a point of balance between flexibility and security. The discussion concludes with some questions about the last lines of the reform of the labor market and with the hope that, even in the face of compelling reasons of economy, labor law can continue to play its traditional role of governing the protection of person.

  19. Elementos del sistema electoral del Congreso Mexicano

    Directory of Open Access Journals (Sweden)

    Aldo Medina García

    2013-08-01

    Full Text Available El presente artículo es un estudio de los componentes del sistema electoral, diseñado por el legislador mexicano para integrar al parlamento federal. Estudio desarrollado a sabiendas de la importancia que reviste el sistema electoral como un medio que permite a los ciudadanos convertir su voto expresado en las urnas en escaños a favor de determinado candidato o partido. En dicho análisis tomamos en cuenta la evolución constitucional del sistema electoral mexicano, la participación de las fuerzas minoritarias en la integración del Senado y de la Cámara de Diputados, la división que se hace del territorio en circunscripciones electorales, la barrera electoral que se fija a los partidos políticos para acceder a la representación en el Parlamento, la fórmula de asignación que se aplica a la votación obtenida, para finalmente concluir que el sistema electoral mexicano es esencialmente mayoritario aun cuando se vista de proporcional.

  20. OBJETIVO DEL DESARROLLO DEL MILENIO 7

    Directory of Open Access Journals (Sweden)

    Margarita M. Pérez O.

    2013-10-01

    Full Text Available Los Objetivos de Desarrollo del Milenio, también conocidos como los Objetivos del Milenio, constituyeron las metas finales que aprobaron los dirigentes mundiales, 189 jefes de estado y de gobierno en la Cumbre del Milenio de las Naciones Unidas celebrada en Nueva York en el año 2000, en la cual los Estados miembros de la organización reafirmaron su compromiso de luchar por un mundo en el que el desarrollo sostenible y la eliminación de la pobreza tuvieran máxima prioridad1 . En la cumbre se definió la Declaración del Milenio, la cual detalla los objetivos, principios, valores, metas y acciones para erradicar la pobreza Mundial hacia el año 2015, todos ellos ratificados con alto interés y acción estratégica de carácter global, como marco para la medición de los progresos en materia de desarrollo.

  1. 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

  2. Heavy-ion dosimetry

    International Nuclear Information System (INIS)

    Schimmerling, W.

    1980-03-01

    This lecture deals with some of the more important physical characteristics of relativistic heavy ions and their measurement, with beam delivery and beam monitoring, and with conventional radiation dosimetry as used in the operation of the BEVALAC biomedical facility for high energy heavy ions (Lyman and Howard, 1977; BEVALAC, 1977). Even so, many fundamental aspects of the interaction of relativistic heavy ions with matter, including important atomic physics and radiation chemical considerations, are not discussed beyond the reminder that such additional understanding is required before an adequte perspective of the problem can be attained

  3. IN MEMORIAM ION VATAMANU

    Directory of Open Access Journals (Sweden)

    S.P. Palii

    2012-12-01

    Full Text Available A dreamer in his creative solitude, an objective and lucid analyst of history and contemporaneity, an energetic and decisive leader with an uncanny ability for crisis management – all these describe Ion Vatamanu. His wife Elena and daughters Mihaela, Mariana, Leontina treasure a personal universe in which the magical spark of Ion Vatamanu’s love and joy of life meld the everyday in and out of poetry. Ion Vatamanu’s instantaneous connection to the audiences and deeply felt words still touch the hearts of his many colleagues and friends. Downloads: 2

  4. Multivalent ion conducting solids

    Energy Technology Data Exchange (ETDEWEB)

    Imanaka, N. [Osaka Univ., Suita, Osaka (Japan). Dept. of Applied Chemistry

    2008-07-01

    Solid electrolytes possess important characteristics for industrial applications. Only a single ionic species can macroscopically migrate in these solids. This paper described a the new NASICON (M-Zr-Nb-P-O) type system, exhibiting an exceptionally high level of trivalent M3+ ion conductivity on polycrystalline solids. The partial substitution of the smaller higher valent Nb5+ ion for Zr4+ stabilized the NASICON phase and realized the M3+ ion conduction in the NASICON structure. It was concluded that the conductivities of the series are comparable to those of the practically applied solid electrolytes of oxide anion conductors of YSZ and CSZ. 3 refs., 2 figs.

  5. Ion implantation technology

    CERN Document Server

    Downey, DF; Jones, KS; Ryding, G

    1993-01-01

    Ion implantation technology has made a major contribution to the dramatic advances in integrated circuit technology since the early 1970's. The ever-present need for accurate models in ion implanted species will become absolutely vital in the future due to shrinking feature sizes. Successful wide application of ion implantation, as well as exploitation of newly identified opportunities, will require the development of comprehensive implant models. The 141 papers (including 24 invited papers) in this volume address the most recent developments in this field. New structures and possible approach

  6. EPR of uranium ions

    International Nuclear Information System (INIS)

    Ursu, I.; Lupei, V.

    1984-02-01

    A review of the electron paramagnetic resonance data on the uranium ions is given. After a general account of the electronic structure of the uranium free atoms and ions, the influence of the external fields (magnetic field, crystal fields) is discussed. The main information obtained from EPR studies on the uranium ions in crystals are emphasized: identification of the valence and of the ground electronic state, determination of the structure of the centers, crystal field effects, role of the intermediate coupling and of the J-mixing, role of the covalency, determination of the nuclear spin, maqnetic dipole moment and electric quadrupole moment of the odd isotopes of uranium. These data emphasize the fact that the actinide group has its own identity and this is accutely manifested at the beginning of the 5fsup(n) series encompassed by the uranium ions. (authors)

  7. Sensing with Ion Channels

    CERN Document Server

    Martinac, Boris

    2008-01-01

    All living cells are able to detect and translate environmental stimuli into biologically meaningful signals. Sensations of touch, hearing, sight, taste, smell or pain are essential to the survival of all living organisms. The importance of sensory input for the existence of life thus justifies the effort made to understand its molecular origins. Sensing with Ion Channels focuses on ion channels as key molecules enabling biological systems to sense and process the physical and chemical stimuli that act upon cells in their living environment. Its aim is to serve as a reference to ion channel specialists and as a source of new information to non specialists who want to learn about the structural and functional diversity of ion channels and their role in sensory physiology.

  8. Ion exchange phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Bourg, I.C.; Sposito, G.

    2011-05-01

    Ion exchange phenomena involve the population of readily exchangeable ions, the subset of adsorbed solutes that balance the intrinsic surface charge and can be readily replaced by major background electrolyte ions (Sposito, 2008). These phenomena have occupied a central place in soil chemistry research since Way (1850) first showed that potassium uptake by soils resulted in the release of an equal quantity of moles of charge of calcium and magnesium. Ion exchange phenomena are now routinely modeled in studies of soil formation (White et al., 2005), soil reclamation (Kopittke et al., 2006), soil fertilitization (Agbenin and Yakubu, 2006), colloidal dispersion/flocculation (Charlet and Tournassat, 2005), the mechanics of argillaceous media (Gajo and Loret, 2007), aquitard pore water chemistry (Tournassat et al., 2008), and groundwater (Timms and Hendry, 2007; McNab et al., 2009) and contaminant hydrology (Chatterjee et al., 2008; van Oploo et al., 2008; Serrano et al., 2009).

  9. Ion sensing method

    Science.gov (United States)

    Smith, Richard Harding; Martin, Glenn Brian

    2004-05-18

    The present invention allows the determination of trace levels of ionic substances in a sample solution (ions, metal ions, and other electrically charged molecules) by coupling a separation method, such as liquid chromatography, with ion selective electrodes (ISE) prepared so as to allow detection at activities below 10.sup.-6 M. The separation method distributes constituent molecules into fractions due to unique chemical and physical properties, such as charge, hydrophobicity, specific binding interactions, or movement in an electrical field. The separated fractions are detected by means of the ISE(s). These ISEs can be used singly or in an array. Accordingly, modifications in the ISEs are used to permit detection of low activities, specifically, below 10.sup.-6 M, by using low activities of the primary analyte (the molecular species which is specifically detected) in the inner filling solution of the ISE. Arrays constructed in various ways allow flow-through sensing for multiple ions.

  10. Perspectivas del turismo rural

    OpenAIRE

    Szmulewicz Espinosa, Pablo

    1998-01-01

    El documento plantea las tendencias y modalidades actuales del turismo del turismo rural y las condiciones para su desarrollo en Chile. Propone la Acción por un turismo rural integrado y sustentable y analiza la situación de oferta y demanda actual para identificar los desafíos tácticos del turismo rural y las orientaciones estratégicas que conformen una política concreta de fomento para convocatoria y participación de los actores interesados. Fil: Szmulewicz Espinosa, Pablo. Universidad A...

  11. Los muertos del Floreanismo

    OpenAIRE

    Enrique Ayala Mora

    2008-01-01

    El artículo analiza el crimen político durante las primeras décadas de vida de la República del Ecuador. Específicamente centra su estudio en el período dominado por la figura de Juan José Flores, primer presidente del Ecuador. La inestabilidad política, la precariedad de las alianzas entre las élites regionales, la crisis económica generada por las guerras de Independencia, las conspiraciones y la violencia que caracterizaron al período de surgimiento de las repúblicas andinas hicieron del c...

  12. Fractura del ahorcado

    OpenAIRE

    Esteban Roig Fabré; Jorge Lerma; Juan Carlos Correa Barrios; Ivón González Varcárcel

    2003-01-01

    Con el nombre de "fractura del ahorcado" se conocen 2 tipos de lesiones del axis de igual apariencia radiológica, de las cuales la más frecuente es la espondilolistesis traumática del axis. Estas lesiones son afecciones relativamente infrecuentes, que crean problemas de manejo a ortopédicos y neurocirujanos por su comportamiento biomecánico particular. Se hace una revisión de la clasificación y fisiopatología de la lesión, y se describen los métodos actuales de diagnóstico por imagen y de tra...

  13. Tratamiento del pie equino

    OpenAIRE

    Robles, Fernanda

    2012-01-01

    El pie equino varo es una patología frecuente en los pacientes con Encefalopatía crónica no evolutiva (ECNE).Se observó que existe una mayor frecuencia en el sexo masculino. Se realizó un estudio descriptivo, comparativo y secundario, durante el periodo de septiembre del 2006 a septiembre del 2011, con un total de 125 pacientes con Ecne, de los cuales se encontraron 101 con pie equino varo congénito. Objetivo: observar los resultados obtenidos en la rehabilitación del pie equino, en niños de ...

  14. La muerte del mito

    OpenAIRE

    Sánchez-Biosca, Vicente

    1990-01-01

    Habría de ser de nuevo John Ford quien sentenciará la defunción del western en cuanto mito, su imposibilidad de construirse en el vacío de la historia. Y habría de ser en uno de los más lúcidos films de la historia del cine: The Man who shot Liberty Valance (El hombre que mató a Liberty Valance, 1962). Todo en este film posee un reverso: un viaje en ferrocarril abre paso al pueblecito de Shinbone. Pero, en el interior del relato, otro emprendido por el antes pionero y ho...

  15. Del Pasadismo al Futurismo

    OpenAIRE

    Agudo-Martínez, M. J.

    2003-01-01

    Uno de los habituales prejuicios a la hora de abordar el análisis del movimiento futurista, al igual que sucede con el constructivismo, es la consideración del contexto político en el que se desarrollaron ambas vanguardias. Sin embargo, y dejando a un lado un enfoque del arte con finalidad política de signo diverso, habría que insistir en el hecho de que posiblemente sean tanto el futurismo italiano como el constructivismo ruso, los movimientos que con mayor entusiasmo se manifestaron, en un ...

  16. Ion beam diagnosis

    International Nuclear Information System (INIS)

    Strehl, P.

    1994-04-01

    This report is an introduction to ion beam diagnosis. After a short description of the most important ion beam parameters measurements of the beam current by means of Faraday cups, calorimetry, and beam current transformers and measurements of the beam profile by means of viewing screens, profile grids and scanning devices, and residual gas ionization monitors are described. Finally measurements in the transverse and longitudinal phase space are considered. (HSI)

  17. Radio frequency ion source

    CERN Document Server

    Shen Guan Ren; Gao Fu; LiuNaiYi

    2001-01-01

    The study on Radio Frequency Ion Source is mainly introduced, which is used for CIAE 600kV ns Pulse Neutron Generator; and obtained result is also presented. The RF ion source consists of a diameter phi 25 mm, length 200 mm, coefficient of expansion =3.5 mA, beam current on target >=1.5 mA, beam spot =100 h.

  18. Ion exchange equilibrium constants

    CERN Document Server

    Marcus, Y

    2013-01-01

    Ion Exchange Equilibrium Constants focuses on the test-compilation of equilibrium constants for ion exchange reactions. The book first underscores the scope of the compilation, equilibrium constants, symbols used, and arrangement of the table. The manuscript then presents the table of equilibrium constants, including polystyrene sulfonate cation exchanger, polyacrylate cation exchanger, polymethacrylate cation exchanger, polysterene phosphate cation exchanger, and zirconium phosphate cation exchanger. The text highlights zirconium oxide anion exchanger, zeolite type 13Y cation exchanger, and

  19. Miniaturized Ion Mobility Spectrometer

    Science.gov (United States)

    Kaye, William J (Inventor); Stimac, Robert M. (Inventor)

    2017-01-01

    By utilizing the combination of a unique electronic ion injection control circuit in conjunction with a particularly designed drift cell construction, the instantly disclosed ion mobility spectrometer (IMS) achieves increased levels of sensitivity, while achieving significant reductions in size and weight. The instant IMS is of a much simpler and easy to manufacture design, rugged and hermetically sealed, capable of operation at high temperatures to at least 250 degrees Centigrade, and is uniquely sensitive, particularly to explosive chemicals.

  20. Ion implantation - an introduction

    International Nuclear Information System (INIS)

    Townsend, P.D.

    1986-01-01

    Ion implantation is a widely used technique with a literature that covers semiconductor production, surface treatments of steels, corrosion resistance, catalysis and integrated optics. This brief introduction outlines advantages of the technique, some aspects of the underlying physics and examples of current applications. Ion implantation is already an essential part of semiconductor technology while in many other areas it is still in an early stage of development. The future scope of the subject is discussed. (author)

  1. Improving Ion Computed Tomography

    DEFF Research Database (Denmark)

    Hansen, David Christoffer

    2014-01-01

    løsninger i stedet sat bruge ion CT, hvor patienten skannes med de samme partikler, der også bruges til selve strålebehandlingen. Med ion CT kan man beregne partiklernes rækkevidde med en præcision, der erbedre end 1.0%, men ion CT har også visse begrænsninger. Blandt andet gør den begrænsede rækkevidde af...... ionerne, at man ikke kan skanne områder tykkere end 30 − 37cm, alt afhængig af acceleratoren på behandlingsstedet. I denne ph.d afhandling undersøges flere af disse begrænsninger. Her præsenteres en ny algoritme, som kombinere ion CT med de røntgenbilleder, der laves i behandlingsrummet. Dermed kan man...... rekonstruere ion CT billeder, selvom partiklerne kun kan nå igennem patienten i halvdelen af de vinkler, man normalt ville skanne fra. Simulationer af ion CT er i høj grad afhængige af de fysiske modeller, der bruges til kerne-spaltning. Modellerne blev i denne afhandling undersøgt i Monte Carlo koden SHIELD...

  2. Collective focusing ion accelerator

    International Nuclear Information System (INIS)

    Goldin, F.J.

    1986-01-01

    The principal subject of this dissertation is the trapping confinement of pure electron plasmas in bumpy toroidal magnetic fields, with particular attention given to the trapping procedure and the behavior of the plasma during the final equilibrium. The most important aspects of the equilibrium studied were the qualitative nature of the plasma configuration and motion and its density, distribution and stability. The motivation for this study was that an unneutralized cloud of electrons contained in a toroidal system, sufficiently dense and stable, may serve to electrostatically focus ions (against centrifugal and self space charge forces) in a cyclic ion accelerator. Such an accelerator, known as a Collective Focusing Ion Accelerator (CFIA) could be far smaller than conventional designs (which use external magnetic fields directly to focus the ions) due to the smaller gyro-radium of an electron in a magnetic field of given strength. The electron cloud generally drifted poloidally at a finite radius from the toroidal minor axis. As this would preclude focusing ions with such clouds, damping this motion was investigated. Finite resistance in the normally perfectly conductive vessel wall did this. In further preparation for a working CFIA, additional experiments studied the effect of ions on the stability of the electron cloud

  3. 2010 ion run: completed!

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    After a very fast switchover from protons to lead ions, the LHC has achieved performances that allowed the machine to exceed both peak and integrated luminosity by a factor of three. Thanks to this, experiments have been able to produce high-profile results on ion physics almost immediately, confirming that the LHC was able to keep its promises for ions as well as for protons.   First direct observation of jet quenching. A seminar on 2 December was the opportunity for the ALICE, ATLAS and CMS collaborations to present their first results on ion physics in front of a packed auditorium. These results are important and are already having a major impact on the understanding of the physics processes that involve the basic constituents of matter at high energies. In the ion-ion collisions, the temperature is so high that partons (quarks and gluons), which are usually constrained inside the nucleons, are deconfined to form a highly dense and hot soup known as quark-gluon plasma (QGP). The existence of ...

  4. El asunto del Juno Trader

    OpenAIRE

    Bou Franch, Valentín

    2005-01-01

    En este trabajo se analiza la Sentencia del Tribunal Internacional de Derecho del Mar en el asunto del Juno Trader. El trabajo centra sobre todo su atención en el análisis del procedimiento de pronta liberación de buques, así como en lo que hay que entender como 'fianza razonable' en estos casos.

  5. Present status of NIRS ECR ion sources

    NARCIS (Netherlands)

    Muramatsu, M.; Kitagawa, A.; Iwata, Y.; Yamamoto, K.; Ogawa, H.; Hojo, S.; Sakamoto, Y.; Honma, T.; Takasugi, W.; Wakaisami, M.; Yoshida, Y.; Kubo, T.; Kato, Y.; Biri, S.; Drentje, A. G.

    Four ECR ion sources have been operated in National Institute of Radiological Sciences (NIRS). Two ECR ion sources supply various ion species for the Heavy Ion Medical Accelerator in Chiba (HIMAC). The 10GHz NIRS-ECR ion source mainly produces C2+ ions for the heavy-ion therapy. Ions of Si, Ar, Fe,

  6. Ion mixing and numerical simulation of different ions produced in the ECR ion source

    International Nuclear Information System (INIS)

    Shirkov, G.D.

    1996-01-01

    This paper is to continue theoretical investigations and numerical simulations in the physics of ECR ion sources within the CERN program on heavy ion acceleration. The gas (ion) mixing effect in ECR sources is considered here. It is shown that the addition of light ions to the ECR plasma has three different mechanisms to improve highly charged ion production: the increase of confinement time and charge state of highly ions as the result of ion cooling; the concentration of highly charged ions in the central region of the source with high energy and density of electrons; the increase of electron production rate and density of plasma. The numerical simulations of lead ion production in the mixture with different light ions and different heavy and intermediate ions in the mixture with oxygen, are carried out to predict the principal ECR source possibilities for LHC applications. 18 refs., 23 refs

  7. La escritura del Yo

    Directory of Open Access Journals (Sweden)

    Patricio Landaeta Mardones

    2013-11-01

    Full Text Available Si la creación de una imagen fidedigna del mundo fue la condición de la conquista cognitiva y económica de la tierra, las imágenes mediáticas circulan hoy en día a la manera de un montaje que organiza los sujetos como elementos de un territorio. En esta presentación abordaremos el cruce entre estos dos hechos, entre la escritura del mundo y la de los sujetos, a partir de la idea de Fabulación para mostrar otra escritura del mundo y del yo, leyendo textos e imágenes de la Primera buena Corónica y Buen Gobierno de Felipe Guaman Poma de Ayala.

  8. Las identidades del dinero

    Directory of Open Access Journals (Sweden)

    CELSO SÁNCHEZ CAPDEQUÍ

    2005-01-01

    Full Text Available A lo largo del trabajo se ha pretendido desvelar los momentos sociales y simbólicos que constituyen la extensa biografía del dinero. En ausencia de una racionalidad económica diferenciada, el dinero nace, de forma no deliberada, en el templo bajo la atmósfera sacrificial, comparece en la modernidad como medio técnico que representa la esperanza del individuo propietario en la bonhomía del mercado como elemento pacificador de las costumbres sociales, y arriba a nuestra posmodernidad como fin en sí mismo que, convertido en bit desmaterializado, aspira a no dejar de circular por el nuevo espacio virtual.

  9. Carta del Editor

    OpenAIRE

    Luis Eladio Proaño

    2015-01-01

    El artículo de fondo busca esclarecer una posible manipulación de la información por parte del gobierno de Aznar sobre el ataque terrorista del 11 de marzo en Madrid, cuál fue la participación de los partidos políticos y cual la reacción del pueblo español. En otro tema se resalta la actividad cumplida por el CIESPAL en sus 45 años de labor. El tema de la lectura y el libro es abordado ante la aparición del e-book. Se habla sobre el ciberperiodismo, la prensa gratuita, las nuevas modalidades ...

  10. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available La millonaria contratación del futbolista David Beckham, un fenómeno del mercado, ha provocado cuestionamientos a los que se busca respuesta. Es tema de análisis el por qué el betseller "Harry Potter" ha causado tanta conmoción en la opinión pública. Respecto al periodista cibernético, se señalan los contornos del presente y atisban las posibilidades del futuro de esta nueva profesión. El tratamiento de los mitos de la prensa, los temores de la Ley mordaza venezolana y la brutalidad de los video juegos e Internet son temas de enorme interés. Se comenta las pocas veces que la prensa reflexiona sobre la comunicación corporal y la anorexia.

  11. Los muertos del Floreanismo

    Directory of Open Access Journals (Sweden)

    Enrique Ayala Mora

    2008-06-01

    Full Text Available El artículo analiza el crimen político durante las primeras décadas de vida de la República del Ecuador. Específicamente centra su estudio en el período dominado por la figura de Juan José Flores, primer presidente del Ecuador. La inestabilidad política, la precariedad de las alianzas entre las élites regionales, la crisis económica generada por las guerras de Independencia, las conspiraciones y la violencia que caracterizaron al período de surgimiento de las repúblicas andinas hicieron del crimen político un “vicio de nacimiento”. El asesinato del general Antonio José de Sucre, la muerte de los miembros de la sociedad El Quiteño Libre, el homicidio de Juan Otamendi, entre otros, hicieron patente esta característica.

  12. Diario del General Santander

    Directory of Open Access Journals (Sweden)

    Guillermo Hernández De Alba

    1963-06-01

    Full Text Available El doctor Rafael Martínez Briceño, eminente médico legista y abogado con notables títulos en la cultura colombiana como humanista y bibliófilo de rara erudición, posee una de las bibliotecas privadas más ricas del país, donde están representados en ediciones príncipes o rarísimas, los ingenios del Renacimiento y de la cultura universal del Barroco, así como las más raras ediciones impresas en hispanoamérica a partir del siglo XVI, especialmente relacionadas con las letras neogranadinas y colombianas.

  13. Ion implantation for materials processing

    International Nuclear Information System (INIS)

    Smidt, F.A.

    1983-01-01

    This book reviews current research on ion implantation for materials processing as a viable technique for improving surface properties of metals and alloys-wear, fatigue, and corrosion. An introductory section on new potential applications of ion beam technology is provided. Contents: New potential applications of ion beam technology; ion implantation science and technology; wear and fatigue; corrosion; other research areas

  14. El financiamiento del terrorismo

    OpenAIRE

    Díaz Molina, Jenory

    2008-01-01

    El sector financiero aplica actualmente medidas preventivas contra el delito de lavado de dinero. Hoy día es necesario ampliar esos controles para abarcar también el delito de financiamiento del terro - rismo, tomando en consideración las similitudes y diferencias entre ambos. Costa Rica recientemente tipificó el delito de financiamiento del te rrorismo con el fin de cumplir con compromisos internacionales

  15. Responsabilidad profesional del fisioterapeuta

    OpenAIRE

    Fernández Martínez, Silvia

    2011-01-01

    Los objetivos de esta tesis son: Conocer el origen histórico y legislativo de la Fisioterapia. Analizar las definiciones que hoy existen de la Fisioterapia, y aportar una nueva que refleje la profesión actual. Establecer un marco de derechos y obligaciones del Fisioterapeuta, como profesional sanitario. Y por último, determinar la Responsabilidad Profesional del Fisioterapeuta, en el ámbito Civil, Penal y de la Administración Pública.

  16. Desarrollo Integral del Preescolar

    OpenAIRE

    Montes Hasslocher, Patricia Isabel

    2013-01-01

    Los niño cuyas edades oscilan entre los 2 y los 6 años de edad reciben el nombre de preescolares (etapa también conoconida como infancia temprana). Esta etapa es supremamente importante en la vida porque es aquí donde se sientan las bases del desarrollo posterior. Los adultos cuidadores deben acompañarlo afectuosa y permanentemente para logar su desarrollo integral, y estimularla adquisición de las metas del desarrollo

  17. Ion-selective electrode reviews

    CERN Document Server

    Thomas, J D R

    1983-01-01

    Ion-Selective Electrode Reviews, Volume 5 is a collection of articles that covers ion-speciation. The book aims to present the advancements of the range and capabilities of selective ion-sensors. The topics covered in the selection are neutral carrier based ion-selective electrodes; reference electrodes and liquid junction effects in ion-selective electrode potentiometry; ion transfer across water/organic phase boundaries and analytical; and carbon substrate ion-selective electrodes. The text will be of great use to chemists and chemical engineers.

  18. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available El artículo de fondo busca esclarecer una posible manipulación de la información por parte del gobierno de Aznar sobre el ataque terrorista del 11 de marzo en Madrid, cuál fue la participación de los partidos políticos y cual la reacción del pueblo español. En otro tema se resalta la actividad cumplida por el CIESPAL en sus 45 años de labor. El tema de la lectura y el libro es abordado ante la aparición del e-book. Se habla sobre el ciberperiodismo, la prensa gratuita, las nuevas modalidades de programación en la radio dirigida a todos los públicos. En el cine se analiza "La pasión de Cristo" y el lauro que el festival de Cannnes otorgó a Fahrenheit 9/11. Desde la óptica de la informática agrega dos temas de actualidad: Los derechos digitales y el control del ciberespacio, más la penetración del Internet.

  19. el Valle del Cauca

    Directory of Open Access Journals (Sweden)

    Carlos Humberto Ortiz

    2007-01-01

    Full Text Available Este artículo se enfoca en la identi- ficación de aquellos factores estructurales que explican la pérdida de dinamismo económico de largo plazo en Colombia y, en particular, en el Valle del Cauca. Se examina la competitividad del Valle en relación con Colombia y con el resto del mundo. Se cuestiona la insistencia en una estrategia exportadora como dinamizadora del desarrollo económico. Se identifica que una gran parte de la población está excluida de los beneficios del desarrollo económico. Para construir un modelo de desarrollo que incluya a esta población se recomienda recuperar la senda de la industrialización, invertir en el capital humano (educación de alta calidad, salud, salubridad y nutrición, e invertir en infraestructura. La participación del Estado en estas inversiones sociales es necesaria para disminuir la desigualdad y aumentar el crecimiento económico.

  20. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available Explica las causas del fenómeno de los Talk Shows que han despertado sentimientos contradictorios de rechazo y fascinación por su alto grado de agresividad y el poco respeto a la intimidad humana. Otro tema es el relacionado a que ilusoriamente se creyó que tras la caída del Muro de Berlín, había renacido en los países de Europa Oriental, la libertad de prensa, el articulista da su versión. En el séptimo arte Europa Occidental irrumpe con una nueva corriente, provocativa y audaz el artículo se centra en la crítica a la obra de Von Trier: el niño terrible del cine alemán. En un escenario de corrupción, más la venalidad del fujimorismo y la presencia de Vladimiro Montesinos, es elegido Alejandro Toledo, el artículo destaca el papel de los medios que en gran parte fueron los que trazaron la agenda y determinaron el resultado final de las elecciones en el Perú. Se cuenta la historia de la BBC de Londres y se cierra con un artículo que destaca la importancia del Word del Microsoft.

  1. Ion optics of RHIC EBIS

    Energy Technology Data Exchange (ETDEWEB)

    Pikin, A.; Alessi, J.; Beebe, E.; Kponou, A.; Okamura, M.; Raparia, D.; Ritter, J.; Tan, Y.; Kuznetsov, G.

    2011-09-10

    RHIC EBIS has been commissioned to operate as a versatile ion source on RHIC injection facility supplying ion species from He to Au for Booster. Except for light gaseous elements RHIC EBIS employs ion injection from several external primary ion sources. With electrostatic optics fast switching from one ion species to another can be done on a pulse to pulse mode. The design of an ion optical structure and the results of simulations for different ion species are presented. In the choice of optical elements special attention was paid to spherical aberrations for high-current space charge dominated ion beams. The combination of a gridded lens and a magnet lens in LEBT provides flexibility of optical control for a wide range of ion species to satisfy acceptance parameters of RFQ. The results of ion transmission measurements are presented.

  2. Determination of lutetium (III) hydrolysis constants in the middle of ion force 1M sodium chloride at 303 K; Determinacion de las constantes de hidrolisis del lutecio (III), en medio de fuerza ionica 1M de cloruro de sodio, a 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez R, M.; Solache R, M.J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Ramirez G, J.J.; Rojas H, A. [Universidad Autonoma Metropolitana-Iztapalapa, Mexico D.F. (Mexico). Dept. de Quimica

    1997-07-01

    With the purpose to complete information about the lutetium (III) hydrolysis constants here is used the potentiometric method to determine those in the middle of ion force 1M sodium chloride at 303 K. (Author)

  3. Determination of the hydrolysis constants of Europium (III), in ion strength media 4, 5 and 6 M NaClO{sub 4} at 303 K; Determinacion de las constantes de hidrolisis del Europio (III), en medios de fuerza ionica 4, 5 y 6 M de NaClO{sub 4} a 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Alvarado B, A.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    This work was made with the purpose to complete information about the hydrolysis constants of Europium (III) in high ion strength media. So it was determined at a ion forces media 4, 5 and 6 M of sodium perchlorate at 303 K. The method used was the potentiometric with the aid of the Super quad computer program. In high ion strength media, the measurements of p H do not correspond directly to negative logarithm of the concentration of hydrogen ions, by this it is necessary to calibrate the electrode in these conditions. The Europium was hydrolized at pC{sub H} values greater 6 in all cases. The potentiometric method used under the described experimental conditions is adequate to determine the hydrolysis constants of Europium (III). According to the results and diagrams of chemical species of Europium obtained we can conclude that the hydrolysis constants, differ by its distribution but not in its identity. (Author)

  4. Gerencia del cuidado-gerencia del servicio

    Directory of Open Access Journals (Sweden)

    Marta Palmet Jiménez

    2016-01-01

    Full Text Available La gerencia de este siglo debe estar plenamente identificada con la administración para planear, organizar, decidir y obtener resultados definidos, evaluados y alcanzados a través de las personas. Para poder gerenciar el cuidado se debe saber administrar. El objetivo de enfermería es cuidar; el objetivo de la gerencia es la conducción de la producción de bienes o servicios en las organizaciones. La gerencia del cuidado implica: motivación, creatividad, responsabilidad y ética por parte del cuidador y de quien cuida, claridad de actitud frente al ser y al qué hacer por parte del cuidador. Se puede concluir que la gerencia (administración, el cuidado (producto de calidad, el servicio (valor intangible, querer servir son un trinomio que deben ir de la mano de manera integrada para el logro de los objetivos propuestos por la organización de salud y de enfermería.

  5. Ion-selective electrode reviews

    CERN Document Server

    Thomas, J D R

    1985-01-01

    Ion-Selective Electrode Reviews, Volume 7 is a collection of papers that covers the applications of electrochemical sensors, along with the versatility of ion-selective electrodes. The coverage of the text includes solid contact in membrane ion-selective electrodes; immobilized enzyme probes for determining inhibitors; potentiometric titrations based on ion-pair formation; and application of ion-selective electrodes in soil science, kinetics, and kinetic analysis. The text will be of great use to chemists and chemical engineers.

  6. Efecto de los componentes del agua de mar durante el fenómeno de corrosión por picaduras del cobre

    Directory of Open Access Journals (Sweden)

    García, E.

    1995-10-01

    Full Text Available Copper is the main component in Cu-Ni alloys recommended for sea water applications. This work presents the electrochemical behaviour of copper in presence of different sea water components and its influence on the corrosion attack. The combined action of chloride and sulphate ions are the main responsible factor for the localized corrosion attack in the form of pitting. A significant parabolic relation exists between the critical pitting potential (Ep and the weight ratio of chloride to sulphate (Cl-/SO42- ions. Therefore sulphate ions are an important component for pitting corrosion of copper.

    El cobre es el elemento principal de las aleaciones Cu-Ni recomendadas para aplicaciones marinas. En este trabajo se presenta el comportamiento electroquímico del cobre con los diferentes componentes del agua de mar y el efecto de estos sobre la forma de ataque del cobre. Se observó que los iones cloruro, en unión con los iones sulfato, son los principales causantes del fenómeno de corrosión por picaduras, existiendo, además, una relación significativa entre el potencial crítico de picado (Ep y la relación (Cl-/SO42- de tipo parabólico, lo cual pone de manifiesto la importancia del ion sulfato en el fenómeno de corrosión por picaduras como promotor de este tipo de mecanismo.

  7. Ion temperature gradient driven turbulence with strong trapped ion resonance

    Energy Technology Data Exchange (ETDEWEB)

    Kosuga, Y., E-mail: kosuga@riam.kyushu-u.ac.jp [Institute for Advanced Study, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Itoh, S.-I. [Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Diamond, P. H. [CASS and CMTFO, University of California at San Diego, La Jolla, California 92093 (United States); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon (Korea, Republic of); Itoh, K. [National Institute for Fusion Science, Gifu (Japan); Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Lesur, M. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan)

    2014-10-15

    A theory to describe basic characterization of ion temperature gradient driven turbulence with strong trapped ion resonance is presented. The role of trapped ion granulations, clusters of trapped ions correlated by precession resonance, is the focus. Microscopically, the presence of trapped ion granulations leads to a sharp (logarithmic) divergence of two point phase space density correlation at small scales. Macroscopically, trapped ion granulations excite potential fluctuations that do not satisfy dispersion relation and so broaden frequency spectrum. The line width from emission due only to trapped ion granulations is calculated. The result shows that the line width depends on ion free energy and electron dissipation, which implies that non-adiabatic electrons are essential to recover non-trivial dynamics of trapped ion granulations. Relevant testable predictions are summarized.

  8. Inverted magnetron ion source

    International Nuclear Information System (INIS)

    Singh, B.; Boyarsky, D.

    1985-01-01

    The present invention provides, in a preferred embodiment, a cylindrical stainless steel cathode with end pieces thereon to form a cathode chamber within. In addition, in a preferred embodiment, there is a stainless steel rod which passes axially through the cathode chamber and which is electrically insulated therefrom at the end pieces. The stainless steel cathode has first and second apertures formed therein with the first to be connected to a source of ionizable gas and the second to act as the opening through which there passes a stream of ions to an ion beam target. A magnetic flux source is coupled to the cathode chamber to pass magnetic flux therethrough and a voltage source is connected between the anode and the cathode to provide an electrostatic field therebetween whereby when ionizable gas is fed into the cathode chamber, it is ionized and a stream of ions emanates from the second aperture. In a preferred embodiment there is further provided an electrostatic ion focusing means to focus the ion stream emanating from the second aperture

  9. Ion transport in pigmentation.

    Science.gov (United States)

    Bellono, Nicholas W; Oancea, Elena V

    2014-12-01

    Skin melanocytes and ocular pigment cells contain specialized organelles called melanosomes, which are responsible for the synthesis of melanin, the major pigment in mammals. Defects in the complex mechanisms involved in melanin synthesis and regulation result in vision and pigmentation deficits, impaired development of the visual system, and increased susceptibility to skin and eye cancers. Ion transport across cellular membranes is critical for many biological processes, including pigmentation, but the molecular mechanisms by which it regulates melanin synthesis, storage, and transfer are not understood. In this review we first discuss ion channels and transporters that function at the plasma membrane of melanocytes; in the second part we consider ion transport across the membrane of intracellular organelles, with emphasis on melanosomes. We discuss recently characterized lysosomal and endosomal ion channels and transporters associated with pigmentation phenotypes. We then review the evidence for melanosomal channels and transporters critical for pigmentation, discussing potential molecular mechanisms mediating their function. The studies investigating ion transport in pigmentation physiology open new avenues for future research and could reveal novel molecular mechanisms underlying melanogenesis.

  10. Ion nitriding of aluminium

    International Nuclear Information System (INIS)

    Fitz, T.

    2002-09-01

    The present study is devoted to the investigation of the mechanism of aluminium nitriding by a technique that employs implantation of low-energy nitrogen ions and diffusional transport of atoms. The nitriding of aluminium is investigated, because this is a method for surface modification of aluminium and has a potential for application in a broad spectrum of fields such as automobile, marine, aviation, space technologies, etc. However, at present nitriding of aluminium does not find any large scale industrial application, due to problems in the formation of stoichiometric aluminium nitride layers with a sufficient thickness and good quality. For the purposes of this study, ion nitriding is chosen, as an ion beam method with the advantage of good and independent control over the process parameters, which thus can be related uniquely to the physical properties of the resulting layers. Moreover, ion nitriding has a close similarity to plasma nitriding and plasma immersion ion implantation, which are methods with a potential for industrial application. (orig.)

  11. Collisionless ion acoustic shocks in a negative-ion plasma

    International Nuclear Information System (INIS)

    Sheridan, T.E.

    1999-01-01

    Plasmas containing positive ions and electrons together with an additional negative component (e.g. negative ions or particulates) are of interest in subfields of plasma physics ranging from basic plasma physics (solitons and shocks, dusty plasmas) to ionospheric and space plasmas to plasma processing (electronegative discharges and particulate contamination). Such plasmas support two modes of the ion acoustic wave, a 'slow' mode where positive ions, negative ions and electrons oscillate in phase, and a 'fast' mode where negative ions oscillate out of phase with the other two components. When nonlinear steepening is considered, the fast wave may form a negative-potential solitary wave (NPSW), which, with the addition of dissipation (e.g. ion reflection, collisions, turbulence, electron Landau damping), will either disperse, or, more interestingly, form a shock. Recently, two experiments on the formation of shocks in a Q-machine plasma with negative ions have been reported. A low-temperature, negative-ion component was created when electrons attached to added SF 6 molecules. In such a plasma, the electron and positive ion temperatures are comparable (∼ 0.2 eV), so that when the negative ion concentration is small (< 50%), ion waves are strongly Landau damped since their phase velocity is comparable to the positive ion thermal velocity. However, a large negative ion concentration increases the phase velocity to a point where damping is weak. Conditions are then right for the formation of a shock. We have simulated shock formation in such a plasma

  12. Determinantes del ingreso y del gasto corriente de los hogares

    OpenAIRE

    Muñoz C., Manuel

    2004-01-01

    Este ensayo de investigación empírica analiza los determinantes del ingreso y del gasto en los hogares colombianos. Utilizando un modelo del ciclo de vida con datos de la encuesta de hogares de 1994 y 1995, muestra que el comportamiento del ingreso está afectado principalmente por las características demográficas del hogar y los rasgos socio ocupacionales de sus miembros. El comportamiento del gasto está determinado ante todo por el ingreso y, en menor medida, por las características sociales...

  13. Dynamics of the ion-ion acoustic instability in the thermalization of ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Han, J.H.; Horton, W. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies); Leboeuf, J.N. (Oak Ridge National Lab., TN (United States))

    1992-07-01

    Particle simulation using a nonlinear adiabatic electron response with two streaming ion species and nonlinear theory are used to study the collisionless thermalization of ion beams in a hot electron plasma. The slow beam or subsonic regime is investigated and the criterion for the transition from predominantly light ion to predominantly heavy ion heating is developed. Long-lived ion hole structures a-re observed in the final state.

  14. Acceleration of radioactive ions

    International Nuclear Information System (INIS)

    Laxdal, R.E.

    2003-01-01

    There is an intense interest world-wide in the use of radioactive ion beams (RIBs) for experiment. In many existing or proposed facilities ions are produced or collected at source potential, ionized and re-accelerated. Within the past year three new ISOL based facilities have added dedicated post-accelerators to deliver accelerated RIBs to experiment. The paper gives an overview of RIB accelerators present and future, and explores the inherent features in the various acceleration methods with an emphasis on heavy ion linacs. The ISAC-I and ISAC-II post-accelerators are discussed as examples. Commissioning results and initial operating experience with ISAC-I will be presented

  15. Heavy ion inertial fusion

    International Nuclear Information System (INIS)

    Keefe, D.; Sessler, A.M.

    1980-01-01

    Inertial fusion has not yet been as well explored as magnetic fusion but can offer certain advantages as an alternative source of electric energy for the future. Present experiments use high-power beams from lasers and light-ion diodes to compress the deuterium-tritium (D-T) pellets but these will probably be unsuitable for a power plant. A more promising method is to use intense heavy-ion beams from accelerator systems similar to those used for nuclear and high-energy physics; the present paper addresses itself to this alternative. As will be demonstrated the very high beam power needed poses new design questions, from the ion-source through the accelerating system, the beam transport system, to the final focus. These problems will require extensive study, both theoretically and experimentally, over the next several years before an optimum design for an inertial fusion driver can be arrived at. (Auth.)

  16. Multicomponent ion exchange model

    International Nuclear Information System (INIS)

    Robinson, S.M.; Arnold, W.D.; Byers, C.H.

    1990-01-01

    The optimization of ion-exchange column design becomes increasingly important in applications where high efficiency is required to remove trace components in wastewater to very low discharge requirements and for treating hazardous wastewaters where the disposal costs for secondary waste is extremely high. A predictive mathematical model is being developed for improved design of ion-exchange columns for treatment of wastewaters which are contaminated with trace quantities of Sr-90 and Cs-137. Equilibria isotherms and mass transfer mechanisms are being experimentally determined for isothermal multicomponent ion exchange of Ca, Mg, Na, Ca, and Sr with Ionsive IE-95 chabazite zeolite. These equations are being included in a mathematical model to determine the cation breakthrough curves for different column configurations and operating conditions

  17. Heavy-ion radiography

    International Nuclear Information System (INIS)

    Fabrikant, J.I.; Tobias, C.A.; Holley, W.R.; Benton, E.V.

    1981-01-01

    Heavy-particle radiography has clinical potential as a newly developed noninvasive low-dose imaging procedure that provides increased resolution of minute density differences in soft tissues of the body. The method utilizes accelerated high-energy ions, primarily carbon and neon, at the Bevalac accelerator at the Lawrence Berkeley Laboratory. The research program for medicine utilizes heavy-ion radiography for low-dose mammography, for treatment planning for cancer patients, and for imaging and accurate densitometry of skeletal structures, brain and spinal neoplasms, and the heart. The potential of heavy-ion imaging, and particularly reconstruction tomography, is now proving to be an adjunct to existing diagnostic imaging procedures in medicine, both for applications to the diagnosis, management and treatment of clinical cancer in man, and for the early detection of small soft-tissue tumors at low radiation dose

  18. Microwave ion source

    Science.gov (United States)

    Leung, Ka-Ngo; Reijonen, Jani; Thomae, Rainer W.

    2005-07-26

    A compact microwave ion source has a permanent magnet dipole field, a microwave launcher, and an extractor parallel to the source axis. The dipole field is in the form of a ring. The microwaves are launched from the middle of the dipole ring using a coaxial waveguide. Electrons are heated using ECR in the magnetic field. The ions are extracted from the side of the source from the middle of the dipole perpendicular to the source axis. The plasma density can be increased by boosting the microwave ion source by the addition of an RF antenna. Higher charge states can be achieved by increasing the microwave frequency. A xenon source with a magnetic pinch can be used to produce intense EUV radiation.

  19. Magnetic ions in crystals

    CERN Document Server

    Stevens, K W

    2014-01-01

    There have been many demonstrations, particularly for magnetic impurity ions in crystals, that spin-Hamiltonians are able to account for a wide range of experimental results in terms of much smaller numbers of parameters. Yet they were originally derived from crystal field theory, which contains a logical flaw; electrons on the magnetic ions are distinguished from those on the ligands. Thus there is a challenge: to replace crystal field theory with one of equal or greater predictive power that is based on a surer footing. The theory developed in this book begins with a generic Hamiltonian, on

  20. Ion-selective electrodes

    CERN Document Server

    Mikhelson, Konstantin N

    2013-01-01

    Ion-selective electrodes (ISEs) have a wide range of applications in clinical, environmental, food and pharmaceutical analysis as well as further uses in chemistry and life sciences. Based on his profound experience as a researcher in ISEs and a course instructor, the author summarizes current knowledge for advanced teaching and training purposes with a particular focus on ionophore-based ISEs. Coverage includes the basics of measuring with ISEs, essential membrane potential theory and a comprehensive overview of the various classes of ion-selective electrodes. The principles of constructing I

  1. Small Column Ion Exchange

    International Nuclear Information System (INIS)

    Huff, Thomas

    2010-01-01

    Small Column Ion Exchange (SCIX) leverages a suite of technologies developed by DOE across the complex to achieve lifecycle savings. Technologies are applicable to multiple sites. Early testing supported multiple sites. Balance of SRS SCIX testing supports SRS deployment. A forma Systems Engineering Evaluation (SEE) was performed and selected Small Column Ion Exchange columns containing Crystalline Silicotitanate (CST) in a 2-column lead/lag configuration. SEE considered use of Spherical Resorcinol-Formaldehyde (sRF). Advantages of approach at SRS include: (1) no new buildings, (2) low volume of Cs waste in solid form compared to aqueous strip effluent; and availability of downstream processing facilities for immediate processing of spent resin.

  2. Intense negative heavy ion sources

    Science.gov (United States)

    Mori, Yoshiharu; Takagi, Akira; Ikegami, Kiyoshi; Ueno, Akira; Fukumoto, Sadayoshi

    1990-08-01

    Negative ion sources based on plasma-surface interactions (BLAKE ion source) have been developed at KEK for producing negative heavy ions. The first negative heavy ion source (BLAKE-II) was developed by modifying the ordinary negative hydrogen ion source with converter (BLAKE-I) placed into the plasma. It generates various species of negative heavy ions with intense beam currents. For example, a more than 10 mA Au- ion beam was obtained from the ion source. Recently, the large scaled negative heavy ion source (BLAKE-III) has been developed and in the preliminary test experiment, more than 100 mA Cu- ion beam has been stably obtained with a 10% duty factor in pulsed operation. The BLAKE-II ion source was attached to the BNL 15 MV and Tsukuba University TANDEM accelerators and large current negative heavy ion beams were successfully accelerated in pulsed mode operation. Also, it was found that the space charge effect should be carefully considered for such a large current acceleration in a tandem accelerator, especially at the injection beam line and low energy end. In order to examine the negative ion formation process fundamentally, negative ion production probability related on sputtered particle velocity was measured and the results showed exponential dependence of the production probability on particle velocity as Norskov and Lindquist's theory predicted.

  3. Las carreras del futuro

    Directory of Open Access Journals (Sweden)

    Luis Piscoya Hermoza

    2011-07-01

    Full Text Available La primera década del siglo XXI ha estado signada por un énfasis en los estudiosde prospectiva, los mismos que, a partir de procesos de complejizacióny articulación de la sociedad planetaria como son la digitalización, el progresivodeterioro del medio ambiente, la necesidad del cambio de la matriz energéticay la globalización del mercado, han ensayado hipótesis para identificar lastendencias que se fortalecerán y profundizarán durante las próximas décadas.Desde el punto de vista metodológico, existen muchas maneras de clasificarlaspara conceptualizarlas y entenderlas mejor. Sin embargo, considerando lanaturaleza de esta edición nos proponemos enfocar directamente aquellas queestán estrechamente ligadas a la formación universitaria.Naturalmente, no pensamos que estamos ante tendencias inevitables en lamedida que epistemológicamente la creencia en leyes históricas deterministases insostenible y la práctica social nos muestra que la construcción del futuroes nuestra responsabilidad y siempre rebasa las mejores previsiones.

  4. Dalt del tren

    Directory of Open Access Journals (Sweden)

    Jaume Subirana

    2001-11-01

    Full Text Available Ens consta que la saviesa popular hi toca més del que a aquest temps d’enquestes, telèfons mòbils i targetes de crèdit li ve de gust admetre, per això em fa gràcia, en veure la pausada però continuada intrusió de la cultura catalana a Internet, recordar les cançons de quan era petit: “Dalt del tren, tots anem-hi dalt del tren, hi ha lloc per tota la gent”, dèiem, i “El tren pinxo de Banyoles és el més bonic que hi ha, ple de llaunes i cassoles i barrets de capellà”. I resulta que per una vegada a la vida hem pujat, efectivament, dalt del tren que passava per l’estació de Catalunya i en cinc anys hem passat de gairebé res a prou pàgines amb un contingut, a més, apreciable i, sobretot, a un petit teixit de persones i institucions que han entès la importància de la revolució comunicativa que Internet representa i que hi teixeixen i projecten webs amb el convenciment dels conversos.

  5. La espiral del mestizaje

    Directory of Open Access Journals (Sweden)

    Guillermo Cervantes

    2009-01-01

    Full Text Available El presente ensayo explora el papel jugado por el mestizaje como instrumento para forjar una identidad nacional en México; donde lo indígena convive y se fusiona con lo europeo, en la persecución y construcción de algo entendido propiamente como mexicano. Partiendo desde la época colonial en la Nueva España, abordaremos el papel concedido al indígena mexicano y su lenta inclusión en la sociedad mediante la adopción de prácticas consideradas como occidentales y civilizadas en detrimento de sus prácticas indígenas tradicionales, consideradas primitivas y atrasadas, como medio de asimilación. Fenómeno que más tarde habría de proponer al mestizo como estereotipo de la identidad nacional mexicana durante el siglo XIX; y que culminaría en su consolidación a principios del siglo XX. Así mismo se aborda la percepción del mestizaje como medio de civilización en la idiosincrasia del mexicano y del méxico-americano para culminar con una evolución de la constante búsqueda de lo occidental, esta vez mediante la asimilación al modo de vida estadounidense, como continuación del proceso civilizatorio entendido como mestizaje

  6. Apostillas acerca del postrabajo

    Directory of Open Access Journals (Sweden)

    Arturo Torrecilla

    2000-04-01

    Full Text Available El más reciente debate en torno al postrabajo transforma la herencia de los dos ciclos que le precedieron desde los años setenta. El primero se correspondía con la crítica de la división social y técnica de labores informada por una filosofía de la alienación o bien por una rectificación de la arquitectónica marxista pero salvaguardando la promesa laborista del buen trabajo. El segundo ciclo hacía eco del rechazo a las cadenas de montaje fordistas y se abría al horizonte de la abolición del trabajo salarial, manteniendo sin embargo el abolengo del sujeto unitario de la historia. La presente escena asume una densidad mayor, producto del encuentro entre las nuevas tecnologías informacionales, las discusiones en el ámbito de la sociología y la antropología, de la tecnología y la ciencia, junto al dueto que inaugura el posmodernismo.

  7. APOSTILLAS ACERCA DEL POSTRABAJO

    Directory of Open Access Journals (Sweden)

    Arturo Torrecilla

    2000-01-01

    Full Text Available El más reciente debate en torno al postrabajo transforma la herencia de los dos ciclos que le precedieron desde los años setenta. El primero se correspondía con la crítica de la división social y técnica de labores informada por una filosofía de la alienación o bien por una rectificación de la arquitectónica marxista pero salvaguardando la promesa laborista del buen trabajo. El segundo ciclo hacía eco del rechazo a las cadenas de montaje fordistas y se abría al horizonte de la abolición del trabajo salarial, manteniendo sin embargo el abolengo del sujeto unitario de la historia. La presente escena asume una densidad mayor, producto del encuentro entre las nuevas tecnologías informacionales, las discusiones en el ámbito de la sociología y la antropología, de la tecnología y la ciencia, junto al dueto que inaugura el posmodernismo.

  8. Historia del vuelo aviano

    Directory of Open Access Journals (Sweden)

    Sanz, José Luis

    1998-12-01

    Full Text Available Not available.El análisis del registro fósil proporciona información sobre la historia evolutiva del aparato volador aviano y el origen y desarrollo del vuelo moderno. Existen dos hipótesis alternativas para explicar las complejas presiones de selección que configuraron la aparición del vuelo. La propuesta del corredor («desde el suelo hacia arriba» es la que mejor se ajusta a la evidencia disponible. El ave primitiva Archaeopteryx produciría, probablemente, algún tipo de vuelo batido, aunque su capacidad de maniobra, despegue y aterrizaje sería limitada. El vuelo activo moderno comenzó, durante el Cretácico inferior, con las aves ornitotoraces basales, como Iberomesornis. No obstante, esta ave primitiva, cuya capacidad de vuelo estaba claramente incrementada con respecto a la condición ancestral presente en Archaeopteryx, tampoco parece tener las perfectas habilidades voladoras de las aves modernas.

  9. En defensa del arte del performance

    Directory of Open Access Journals (Sweden)

    Guillermo Gómez-Peña

    2005-12-01

    Full Text Available ¿Qué es "exactamente" el arte del performance? Y ¿qué es lo que hace a un artista de performance ser, pensar y actuar como tal? En este texto, intentaré responder estas preguntas de manera elíptica, creando un bosquejo poético de un performero parado sobre el mapa del arte del performance en el nuevo siglo, según como yo lo percibo. Para ser congruente con mi propia práctica estética, al tiempo que intento responder a estas espinosas preguntas, atravesaré constantemente las fronteras entre la teoría y la crónica; entre los escabrosos terrenos de lo personal y lo social (entre el "yo" y el "nosotros", con la esperanza de descubrir algunas encrucijadas y puentes interesantes. Trataré de escribir con toda la pasión, el valor y la claridad que pueda, aún que la naturaleza resbaladiza y en permanente transformación de este 'campo' nos dificulta en extremo trazar definiciones simplistas.What does it mean performance art? What does it make a performance artist to think, be and act as such? In this text, I will try to answer these questions in a somewhat elliptic fashion, as if it were a poetic essay of a performer standing over the map of performance art in the new century, as I perceive it. In order to be consistent with my own aesthetic practice, at the same time that I attempt to answer these thorny questions, I will constantly cross the frontiers between theory and chronicle; between the frightening fields of the personal and the social ( between "I" and "we", hoping to discover some interesting bridges and crossroads. I will write with all possible passion, value and clarity though the sliding nature and constant transformation of this 'field' make it extremely difficult to come with simplistic definitions.

  10. Ion-selective electrode reviews

    CERN Document Server

    Thomas, J D R

    1982-01-01

    Ion-Selective Electrode Reviews, Volume 3, provides a review of articles on ion-selective electrodes (ISEs). The volume begins with an article on methods based on titration procedures for surfactant analysis, which have been developed for discrete batch operation and for continuous AutoAnalyser use. Separate chapters deal with detection limits of ion-selective electrodes; the possibility of using inorganic ion-exchange materials as ion-sensors; and the effect of solvent on potentials of cells with ion-selective electrodes. Also included is a chapter on advances in calibration procedures, the d

  11. Analytical applications of ion exchangers

    CERN Document Server

    Inczédy, J

    1966-01-01

    Analytical Applications of Ion Exchangers presents the laboratory use of ion-exchange resins. This book discusses the development in the analytical application of ion exchangers. Organized into 10 chapters, this book begins with an overview of the history and significance of ion exchangers for technical purposes. This text then describes the properties of ion exchangers, which are large molecular water-insoluble polyelectrolytes having a cross-linked structure that contains ionic groups. Other chapters consider the theories concerning the operation of ion-exchange resins and investigate th

  12. Molecular ion sources for low energy semiconductor ion implantation (invited).

    Science.gov (United States)

    Hershcovitch, A; Gushenets, V I; Seleznev, D N; Bugaev, A S; Dugin, S; Oks, E M; Kulevoy, T V; Alexeyenko, O; Kozlov, A; Kropachev, G N; Kuibeda, R P; Minaev, S; Vizir, A; Yushkov, G Yu

    2016-02-01

    Smaller semiconductors require shallow, low energy ion implantation, resulting space charge effects, which reduced beam currents and production rates. To increase production rates, molecular ions are used. Boron and phosphorous (or arsenic) implantation is needed for P-type and N-type semiconductors, respectively. Carborane, which is the most stable molecular boron ion leaves unacceptable carbon residue on extraction grids. A self-cleaning carborane acid compound (C4H12B10O4) was synthesized and utilized in the ITEP Bernas ion source resulting in large carborane ion output, without carbon residue. Pure gaseous processes are desired to enable rapid switch among ion species. Molecular phosphorous was generated by introducing phosphine in dissociators via 4PH3 = P4 + 6H2; generated molecular phosphorous in a pure gaseous process was then injected into the HCEI Calutron-Bernas ion source, from which P4(+) ion beams were extracted. Results from devices and some additional concepts are described.

  13. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Blasco Fernando Checa Montúfar

    2015-01-01

    Full Text Available La sección "Ética, Medios y Periodismo", se centra en la responsabilidad ética del periodista y del medio. En la sección "Los medios en el medio", se destaca el rol nodal y las tres funciones fundamentales que los medios tienen en la sociedad contemporánea: legitimar lo que transmiten, establecer la realidad (Agenda Setting y mediar, para bien o mal, entre el poder y la ciudadanía. "Nuevas Tecnologías" se recrea en recordar la gestión de la Agencia Informativa Púlsar más el artículo sobre el cibermundo. Con la sección "Apuntes" se completa esta entrega con tres artículos: Los periodistas en la mira, Los desafíos comunicacionales del Mercosur y la Lectura como viaje.

  14. Estenosis malignas del estomago

    Directory of Open Access Journals (Sweden)

    José A. Jácome Valderrama

    1953-09-01

    Full Text Available Al hablar de estenosis malignas del estomago, no vamos a referirnos a las obstrucciones producidas por lesiones extrínsecas, en las cuales influye como causa determinante el fenómeno mecánico de compresión exterior, sino a aquellas lesiones que primitivamente se originan en los tejidos del estomago, vale decir en sus paredes u orificios. Las estenosis intrínsecas malignas del estomago son producidas generalmente por tumores derivados de sus diferentes tejidos y por consiguiente se agrupan en dos grandes tipos, a saber: los sarcomas, los carcinomas y los adenocarcinomas, según se deriven de los tejidos de sostén o conjuntivos y de los tejidos glandulares o epiteliales. Es importante tener en cuenta esto, pues la sintomatología de unos y otros varia considerablemente, ya que afectan funciones diferentes.

  15. LA PERSISTENCIA DEL SUBALTERNO

    Directory of Open Access Journals (Sweden)

    John Beverley

    2002-01-01

    Full Text Available Este trabajo es el texto literal de una ponencia presentada en un panel sobre los estudios culturales latinoamericanos en el congreso de LASA en 2001 en Washington DC. Representa la posición desarrollada en el trabajo colectivo del llamado Grupo de Estudios Subalternos Latinoamericano, desde nuestra fundación en 1992 hasta la disolución del grupo en 2001, que sirve como pretexto introductorio para la ponencia. Los otros participantes en el panel eran Walter Mignolo, representando los estudios poscoloniales, Néstor García Canclini y John Kraniauskas, representando los estudios culturales, y Nelly Richard representando la llamada crítica cultural. El trabajo dialoga y debate con cada una de estas posiciones respectivamente desde el punto de vista específico de los estudios subalternos. Concluye con un llamado a una crítica del saber académico en sí.

  16. "La responsabilidad del sujeto"

    Directory of Open Access Journals (Sweden)

    FRANCISCO J. RENGIFO

    2005-01-01

    Full Text Available Interrogar el concepto de responsabilidad en psicoanálisis requiere de un acto de indulgencia con respecto al debate ético que supone. La posición ética del psicoanálisis dista del paradigma filosófico debido a la revolución ética inspirada por Freud y desarrollada por Lacan. El psicoanálisis anuncia un modelo de responsabilidad esencial e inédito que revoluciona todo paradigma ético. La responsabilidad para el psicoanálisis se inscribe en el registro de un "bien decir", que supone el respeto a la singularidad del sujeto y al deseo que lo habita, así como el derecho al enigma que introduce el inconsciente en la cultura.

  17. Estudio del sector Naval de Mar del Plata

    OpenAIRE

    Garrido, Florencia; Alvarez, José Francisco; Belmonte, Juan Carlos; Graña, Fernando Manuel

    2007-01-01

    Fil: Garrido, Florencia. Cámara de la Industria Naval de Mar del Plata; Argentina. Fil: Alvarez, José Francisco. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentina. Fil: Belmonte, Juan Carlos. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentina. Fil: Graña, Fernando Manuel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina.

  18. Optimización de espinelas LiCoyMn2-yO4 para electrodos positivos de baterías recargables de ion-litio mediante ajuste del dopado y de la temperatura de síntesis

    Directory of Open Access Journals (Sweden)

    Mandal, S.

    2004-04-01

    Full Text Available The synthesis of LiCoyMn2‑yO4 (0 Se han sintetizado espinelas LiCoyMn2‑yO4 (0 < y ≤ 0.33 con óptimas propiedades electroquímicas en la región de 4V mediante un procedimiento original basado en la reacción a 750º C entre las espinelas Co3y/2Mn3-3y/2O4 obtenidas a temperatura ambiente y LiOH.H2O. Los materiales obtenidos se han caracterizado por difracción de rayos-X, y la disminución del parámetro de red observada ha sido asociada con el aumento del porcentaje de dopante. Se han estudiado las propiedades electroquímicas mediante ciclaje galvanostático en una celda de litio. Se ha analizado la influencia del dopado en la capacidad, el potencial redox y la ciclabilidad de las espinelas sintetizadas. El compuesto LiCo0.11Mn1.89O4 es el material que presenta las mejores propiedades electroquímicas, con una capacidad inicial de Q = 121.7 mA h g-1 y una reversibilidad por ciclo del 99.86%.

  19. Polyatomic ions from a high current ion implanter driven by a liquid metal ion source

    Science.gov (United States)

    Pilz, W.; Laufer, P.; Tajmar, M.; Böttger, R.; Bischoff, L.

    2017-12-01

    High current liquid metal ion sources are well known and found their first application as field emission electric propulsion thrusters in space technology. The aim of this work is the adaption of such kind of sources in broad ion beam technology. Surface patterning based on self-organized nano-structures on, e.g., semiconductor materials formed by heavy mono- or polyatomic ion irradiation from liquid metal (alloy) ion sources (LMAISs) is a very promising technique. LMAISs are nearly the only type of sources delivering polyatomic ions from about half of the periodic table elements. To overcome the lack of only very small treated areas by applying a focused ion beam equipped with such sources, the technology taken from space propulsion systems was transferred into a large single-end ion implanter. The main component is an ion beam injector based on high current LMAISs combined with suited ion optics allocating ion currents in the μA range in a nearly parallel beam of a few mm in diameter. Different types of LMAIS (needle, porous emitter, and capillary) are presented and characterized. The ion beam injector design is specified as well as the implementation of this module into a 200 kV high current ion implanter operating at the HZDR Ion Beam Center. Finally, the obtained results of large area surface modification of Ge using polyatomic Bi2+ ions at room temperature from a GaBi capillary LMAIS will be presented and discussed.

  20. Ion implantation into diamond

    International Nuclear Information System (INIS)

    Sato, Susumu

    1994-01-01

    The graphitization and the change to amorphous state of diamond surface layer by ion implantation and its characteristics are reported. In the diamond surface, into which more than 10 16 ions/cm 2 was implanted, the diamond crystals are broken, and the structure changes to other carbon structure such as amorphous state or graphite. Accompanying this change of structure, the electric conductivity of the implanted layer shows two discontinuous values due to high resistance and low resistance. This control of structure can be done by the temperature of the base during the ion implantation into diamond. Also it is referred to that by the base temperature during implantation, the mutual change of the structure between amorphous state and graphite can be controlled. The change of the electric resistance and the optical characteristics by the ion implantation into diamond surface, the structural analysis by Raman spectroscopy, and the control of the structure of the implanted layer by the base temperature during implantation are reported. (K.I.)

  1. Ion Mass Determination

    DEFF Research Database (Denmark)

    2010-01-01

    An apparatus (100) is described for determining the mass of ions, the apparatus configured to hold a plasma (101 ) having a plasma potential. The apparatus (100) comprises an electrode (102) having a surface extending in a surface plane and an insulator (104) interfacing with the electrode (102...

  2. Ion Implantation of Polymers

    DEFF Research Database (Denmark)

    Popok, Vladimir

    2012-01-01

    is put on the low-energy implantation of metal ions causing the nucleation and growth of nanoparticles in the shallow polymer layers. Electrical, optical and magnetic properties of metal/polymer composites are under the discussion and the approaches towards practical applications are overviewed....

  3. CLASSICS The Ions

    Indian Academy of Sciences (India)

    solution is called electrolytic dissociation, and this process is a chemical reaction coming under the general laws already discussed. A salt solution gives back the original salt unchanged when it is evaporated, and this proves clearly that the dissociation into ions is reversed when the salt separates. The question arises ...

  4. Heavy ion fusion

    International Nuclear Information System (INIS)

    Hofmann, Ingo

    1993-01-01

    With controlled thermonuclear fusion holding out the possibility of a prolific and clean new source of energy, the goal remains elusive after many years of continual effort. While the conventional Tokamak route with magnetic confinement continues to hit the headlines, other alternatives are now becoming competitive. One possible solution is to confine the thermonuclear fuel pellet by high power beams. Current research and perspectives for future work in such inertial confinement was the subject of the 'Prospects for Heavy Ion Fusion' European Research Conference held in Aghia Pelaghia, Crete, last year. Its main focus was on the potential of heavy ion accelerators as well as recent advances in target physics with high power lasers and light ion beams. Carlo Rubbia declared that high energy accelerators, with their high efficiency, are the most promising approach to economical fusion energy production. However the need for cost saving in the driver accelerator requires new ideas in target design tailored to the particularities of heavy ion beams, which need to be pushed to the limits of high current and phase space density at the same time

  5. Field ion microscopy

    International Nuclear Information System (INIS)

    Ramanathan, D.

    1975-01-01

    The basic features of the Field-Ion Microscope (FIM) and the theory of image formation are explained. Design parameters of the FIM, factors limiting its resolution, interpretation of the image, etc are briefly outlined. Relative merits of the various imaging gases and the applications of the FIM are also covered. (K.B.)

  6. Ion-Beam-Excited Electrostatic Ion Cyclotron Waves

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1976-01-01

    Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field.......Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field....

  7. Compact RF ion source for industrial electrostatic ion accelerator

    Science.gov (United States)

    Kwon, Hyeok-Jung; Park, Sae-Hoon; Kim, Dae-Il; Cho, Yong-Sub

    2016-02-01

    Korea Multi-purpose Accelerator Complex is developing a single-ended electrostatic ion accelerator to irradiate gaseous ions, such as hydrogen and nitrogen, on materials for industrial applications. ELV type high voltage power supply has been selected. Because of the limited space, electrical power, and robust operation, a 200 MHz RF ion source has been developed. In this paper, the accelerator system, test stand of the ion source, and its test results are described.

  8. Ion transport from plasma ion source at ISOLTRAP

    CERN Document Server

    Steinsberger, Timo Pascal

    2017-01-01

    In this report, my work as CERN Summer Student at the ISOLTRAP experiment at ISOLDE is described. A new plasma ion source used as oine source for calibration and implemented before my arrival was commissioned and transportation settings for the produced ions to the ion traps were found. The cyclotron frequencies of 40Ar and the xenon isotopes 129-132Xe were measured using time-of-flight and phase-imaging ion-cyclotron-resonance mass spectroscopy.

  9. La Esencia del marketing

    OpenAIRE

    López-Pinto Ruíz, Bernardo

    2001-01-01

    Una de las finalidades más importantes de toda empresa es el beneficio. En la actualidad, el modo de conseguir más beneficio ya no es únicamente "incrementar el volumen de ventas", sino que la finalidad del beneficio se persigue a través de la satisfacción del cliente, mediante las herramientas de que dispone la dirección comercial, planificando un marketing adecuado al mercado en el que se desea incidir. Este trabajo pretende dar a conocer de forma generalizada y sintética los principales as...

  10. El lenguaje del cerebro

    Directory of Open Access Journals (Sweden)

    Antonio Ibáñez Molina

    2011-04-01

    Full Text Available La introducción de nuevas técnicas de análisis de ritmos EEG en estudio de la comprensión del lenguaje permite explorar esta habilidad humana desde una perspectiva de integración de grupos de redes neuronales. Los ritmos de disparo neuronal que generan estos grupos pueden conectarse por sincronía formando unidades funcionales transitorias distribuidas en diversas áreas del cerebro. En esta revisión comentamos algunos de estos ritmos y su relación con el lenguaje.

  11. Plasticidad del sistema nervioso

    Directory of Open Access Journals (Sweden)

    L. M. Garcia-Segura

    1976-06-01

    Full Text Available En este trabajo se revisan los conocimientos más recientes sobre el fenómeno de la plasticidad del sistéma nervioso, tanto a nivel morfológico como a nivel fisiológico y molecular. Se estudian los cambios morfólogicos y fisiológicos de las neuronas frente a la experiencia. Tambien se considera la adaptación molecular del sistéma nervioso a la información que recibe como la base de todo tipo de plasticidad.

  12. Voz del anciano

    OpenAIRE

    Sarrasqueta-Sáenz, L. (Laura); Marques-Girbau, M. (Margarita); Ruba, D. (David); Fernandez-Gonzalez, S. (Secundino)

    2006-01-01

    La vejez es en sí un fenómeno biológico que no implica necesariamente una enfermedad. Los fenómenos biológicos del envejecimiento se inician en edades muy tempranas y tiene la capacidad de modificarse, preveerse y compensarse. La educación y la preparación para posibles deterioros debe de ser contemplada desde un plano preventivo. En el ser humano la aparición del lenguaje y su vehículo habitual, la voz; representó la posibilidad de aumentar su longevidad. El deterioro...

  13. Storia del pensiero matematico

    CERN Document Server

    Kline, Morris

    1999-01-01

    Costruita con l'intento di presentare le idee oltre ai protagonisti della matematica, questa storia ha il duplice pregio dell'esaustività e della chiarezza. Essa prevede infatti vari livelli di lettura: lo specialista vi trova una messe di dati, fonti e spunti di ricerca, mentre lo studente ha a disposizione un formidabile strumento di consultazione e sintesi. L'arco temporale coperto è vasto: dalla Mesopotamia a Euclide, da Fibonacci all'invenzione del calcolo infinitesimale, da Gauss a Poincare, con un'appendice dedicata agli sviluppi piu recenti scritta appositamente per la prima edizione italiana del 1991, nei «Manuali» Einaudi.

  14. Historia del Lupus

    OpenAIRE

    Alvaro Rodríguez Gama

    2004-01-01

    Libro del Académico Antonio Iglesias (que ganó el Premio Sanofi-Aventis/ Academia Nacional de Medicina). Comentario del Académico Alvaro Rodríguez Gama Egon Lichtenberg, Manuel Elkin Patarroyo, Fernando Chalem, Javier Molina, Rafael Valle, José Fernando Molina y Ricardo Zúñiga entre tantos otros estudiosos y divulgadores de estos temas. El maestro Iglesias Gamarra relaciona además los esfuerzos realizados por otros científicos en Argentina, Chile, México, Perú, Brasil y Vene...

  15. Unstable Electrostatic Ion Cyclotron Waves Exited by an Ion Beam

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1976-01-01

    Electrostatic ion cyclotron waves were observed in a quiescent cesium plasma into which a low‐energy beam of sodium ions was injected. The instability appeared when the beam velocity was above 12 times the ion thermal velocity. The waves propagated along the magnetic field with a velocity somewhat...

  16. Cs+ ion source for secondary ion mass spectrometry

    International Nuclear Information System (INIS)

    Bentz, B.L.; Weiss, H.; Liebl, H.

    1981-12-01

    Various types of cesium ionization sources currently used in secondary ion mass spectrometry are briefly reviewed, followed by a description of the design and performance of a novel, thermal surface ionization Cs + source developed in this laboratory. The source was evaluated for secondary ion mass spectrometry applications using the COALA ion microprobe mass analyzer. (orig.)

  17. ECR ion source based low energy ion beam facility

    Indian Academy of Sciences (India)

    Mass analyzed highly charged ion beams of energy ranging from a few keV to a few MeV plays an important role in various aspects of research in modern physics. In this paper a unique low energy ion beam facility (LEIBF) set up at Nuclear Science Centre (NSC) for providing low and medium energy multiply charged ion ...

  18. Using Ion Exchange Chromatography to Separate and Quantify Complex Ions

    Science.gov (United States)

    Johnson, Brian J.

    2014-01-01

    Ion exchange chromatography is an important technique in the separation of charged species, particularly in biological, inorganic, and environmental samples. In this experiment, students are supplied with a mixture of two substitution-inert complex ions. They separate the complexes by ion exchange chromatography using a "flash"…

  19. Heavy-ion radiography and heavy-ion computed tomography

    International Nuclear Information System (INIS)

    Fabrikant, J.I.; Holley, W.R.; McFarland, E.W.; Tobias, C.a.

    1982-02-01

    Heavy-ion projection and CT radiography is being developed into a safe, low-dose, noninvasive radiological procedure that can quantitate and image small density differences in human tissues. The applications to heavy-ion mammography and heavy-ion CT imaging of the brain in clinical patients suggest their potential value in cancer diagnosis

  20. Heavy-ion radiography and heavy-ion computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.; Holley, W.R.; McFarland, E.W.; Tobias, C.a.

    1982-02-01

    Heavy-ion projection and CT radiography is being developed into a safe, low-dose, noninvasive radiological procedure that can quantitate and image small density differences in human tissues. The applications to heavy-ion mammography and heavy-ion CT imaging of the brain in clinical patients suggest their potential value in cancer diagnosis.

  1. Radioactive ion microscopy

    International Nuclear Information System (INIS)

    Johnson, S.A.

    1980-01-01

    A novel approach has been studied for the characterization of specimens with a spatial resolution at the micron level. The technique dubbed Radioactive Ion Microscopy, (RIM) uses a beam of radioactive ions, specifically tritium ions, of sufficient energy to pass through a thick specimen (e.g. greater than or equal to 10 μm). After passage through the object, the ions are implanted in a stack of thin mylar sheets (1.5 microns thick). Their rest position is proportional to the thickness and the density of the sample transversed. The location of the radioactive species can be pinpointed by autoradiographing the successive mylar foils. The radiographs are photographed and converted into digital data which is used to generate a density map of the object. From these plots, physical and chemical features may be deduced. The feasibility of RIM has been demonstrated with specimen images obtained from different objects exposed to a 3 MeV 3 H + beam. The specimens used included metal grids to examine spatial resolution and a series of biological samples (cork, wood, mosquito wing) to explore the performance and applicability of RIM. On these samples, which were 10 to 30 microns thick with surface areas of up to 1 cm 2 , a lateral resolution of approx. 1.5 microns was achieved. A depth resolution or sensitivity to density gradients of 0.2 mg/cm 2 was obtained. These detailed specimen images can be obtained with low beam exposures, e.g., in the case of tritium approx. 6 x 10 10 ions/cm 2 must be implanted, which corresponds to an irradiation of approx. 10 pA/cm 2 for 1000 s. The corresponding low radiation doses and minimal heat dissipation render RIM well suited for biological specimens. In comparison to light microscopy, RIM features enhanced microscopic capabilities as it can handle objects that are at the same time opaque to light, thick (up to tens of microns), and fragile

  2. Hidden ion population: Revisited

    International Nuclear Information System (INIS)

    Olsen, R.C.; Chappell, C.R.; Gallagher, D.L.; Green, J.L.; Gurnett, D.A.

    1985-01-01

    Satellite potentials in the outer plasmasphere range from near zero to +5 to +10 V. Under such conditions ion measurements may not include the low energy core of the plasma population. In eclipse, the photoelectron current drops to zero, and the spacecraft potential can drop to near zero volts. In regions where the ambient plasma density is below 100 cm -3 , previously unobserved portions of the ambient plasma distribution function can become visible in eclipse. A survey of the data obtained from the retarding ion mass spectrometer (RIMS) on Dynamics Explorer 1 shows that the RIMS detector generally measured the isotropic background in both sunlight and eclipse in the plasma-sphere. Absolute density measurements for the ''hidden'' ion population are obtained for the first time using the plasma wave instrument observations of the upper hybrid resonance. Agreement in total density is found in sunlight and eclipse measurements at densities above 80 cm -3 . In eclipse, agreement is found at densities as low as 20 cm -3 . The isotropic plasma composition is primarily H + , with approx.10% He + , and 0.1 to 1.0% O + . A low energy field-aligned ion population appears in eclipse measurements outside the plasmasphere, which is obscured in sunlight. These field-aligned ions can be interpreted as field-aligned flows with densities of a few particles per cubic centimeter, flowing at 5-20 km/s. The problem in measuring these field-aligned flows in sunlight is the masking of the high energy tail of the field-aligned distribution by the isotropic background. Effective measurement of the core of the magnetospheric plasma distribution awaits satellites with active means of controlling the satellite potential

  3. Negative ion sources for tandem accelerator

    International Nuclear Information System (INIS)

    Minehara, Eisuke

    1980-08-01

    Four kinds of negative ion sources (direct extraction Duoplasmatron ion source, radial extraction Penniing ion source, lithium charge exchange ion source and Middleton-type sputter ion source) have been installed in the JAERI tandem accelerator. The ion sources can generate many negative ions ranging from Hydrogen to Uranium with the exception of Ne, Ar, Kr, Xe and Rn. Discussions presented in this report include mechanisms of negative ion formation, electron affinity and stability of negative ions, performance of the ion sources and materials used for negative ion production. Finally, the author will discuss difficult problems to be overcome in order to get any negative ion sufficiently. (author)

  4. Liberación de iones flúor en materiales dentales

    OpenAIRE

    Salmeron-Váldes, Elías Nahum

    2016-01-01

    Tesis de Doctorado que contiene el análisis y la cuantificación del flúor liberado en algunos materiales dentales como lo son Cementos de Ionómero de vidrio, Selladores de fosas y fisuras, pastas dentales y barnices.

  5. Low-altitude ion heating with downflowing and upflowing ions

    Science.gov (United States)

    Shen, Y.; Knudsen, D. J.; Burchill, J. K.; Howarth, A. D.; Yau, A. W.; James, G.; Miles, D.; Cogger, L. L.; Perry, G. W.

    2017-12-01

    Mechanisms that energize ions at the initial stage of ion upflow are still not well understood. We statistically investigate ionospheric ion energization and field-aligned motion at very low altitudes (330-730 km) using simultaneous plasma, magnetic field, wave electric field and optical data from the e-POP satellite. The high-time-resolution (10 ms) dataset enables us to study the micro-structures of ion heating and field-aligned ion motion. The ion temperature and field-aligned bulk flow velocity are derived from 2-D ion distribution functions measured by the SEI instrument. From March 2015 to March 2016, we've found 17 orbits (in total 24 ion heating periods) with clear ion heating signatures passing across the dayside cleft or the nightside auroral regions. Most of these events have consistent ion heating and flow velocity characteristics observed from both the SEI and IRM instruments. The perpendicular ion temperature goes up to 4.5 eV within a 2 km-wide region in some cases, in which the Radio Receiver Instrument (RRI) sees broadband extremely low frequency (BBELF) waves, demonstrating significant wave-ion heating down to as low as 350 km. The e-POP Fast Auroral Imager (FAI) and Magnetic Field (MGF) instruments show that many events are associated with active aurora and are within downward current regions. Contrary to what would be expected from mirror-force acceleration of heated ions, the majority of these heating events (17 out of 24) are associated with the core ion downflow rather than upflow. These statistical results provide us with new sights into ion heating and field-aligned flow processes at very low altitudes.

  6. Swift Heavy Ions in Matter

    International Nuclear Information System (INIS)

    1989-01-01

    The 1989 Symposium on Swift Heavy Ions in Matter is reported. The aim of the symposium is to evidence another aspect of heavy ions research at the interplay between atomic and solid state physics. The scope of the Symposium includes the fundamental aspects of heavy ion excitation, ionization, charge exchange, energy loss, energy dissipation and relaxation in solids, channeling and coherent effects in crystals and ion induced modifications of materials

  7. Membranes in Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Junbo Hou

    2012-07-01

    Full Text Available Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed.

  8. Nanopatterning by Swift Heavy Ions

    OpenAIRE

    Skupinski, Marek

    2006-01-01

    Today, the dominating way of patterning nanosystems is by irradiation-based lithography (e-beam, DUV, EUV, and ions). Compared to the other irradiations, ion tracks created by swift heavy ions in matter give the highest contrast, and its inelastic scattering facilitate minute widening and high aspect ratios (up to several thousands). Combining this with high resolution masks it may have potential as lithography technology for nanotechnology. Even if this ‘ion track lithography’ would not give...

  9. OPTIMIZACION DE LAS PROPIEDADES DE TRANSPORTE IONICO DEL CONCRETO Y SIMULACION DEL ENSAYO ASTM C1202

    Directory of Open Access Journals (Sweden)

    JUAN LIZARAZO MARRIAGA

    2009-01-01

    Full Text Available En este artículo se presentan los resultados de la simulación computacional del flujo de los principales iones presentes (Cl-, OH-, Na+, y K+ en un ensayo ASTM C1202: "Indicación eléctrica de la resistencia del concreto a la penetración de Iones cloruro". Para la modelación se utilizó un esquema de diferencias finitas definido mediante la ecuación de Nernst - Plank con un campo eléctrico variable, la cual describe los movimientos iónicos en un material poroso saturado. Para lograr esto, los resultados de un nuevo ensayo electroquímico diseñado para medir el potencial de membrana, en compañía de la corriente eléctrica, fueron optimizados para obtener los coeficientes intrínsicos de difusión, la composición inicial de la solución de poros, la capacidad de fijación de cloruros y la porosidad de la mezcla de concreto.

  10. Numerical simulation of ion temperature gradient driven modes in the presence of ion-ion collisions

    International Nuclear Information System (INIS)

    Xu, X.Q.

    1990-08-01

    Ion temperature gradient driven modes in the presence of ion-ion collisions in a toroidal geometry with trapped ions have been studied by using a 1 2/2 d linearized gyro-kinetic particle simulation code in the electrostatic limit. The purpose of the investigation is to try to understand the physics of flat density discharges, in order to test the marginal stability hypothesis. Results giving threshold conditions of L Ti /R 0 , an upper bound on k χ , and linear growth rates and mode frequencies over all wavelengths for the collisionless ion temperature gradient driven modes are obtained. The behavior of ion temperature gradient driven instabilities in the transition from slab to toroidal geometry, with trapped ions, is shown. A Monte Carlo scheme for the inclusion of ion-ion collisions, in which ions can undergo Coulomb collisional dynamical friction, velocity space diffusion and random walk of guiding centers, has been constructed. The effects of ion-ion collisions on the long wave length limit of the ion modes is discussed. 44 refs., 12 figs

  11. La equinoterapia en las distintas alteraciones del desarrollo del menor.

    OpenAIRE

    Chamorro González, Mireya

    2015-01-01

    La equinoterapia consiste en la utilización del caballo como un método terapéutico para rehabilitar a personas con discapacidad. Esta terapia es considerada una gran alternativa para aumentar el autoestima de los que sufren algún tipo de discapacidad, también a través de esta terapia se mejora y fortalece el estado emocional, así del mismo modo ayuda a mejorar la manera de desenvolverse en su entorno social. Esta terapia se realiza a través de la trasmisión del calor corporal del caballo, del...

  12. Gestión del riesgo del cambio (segunda parte)

    OpenAIRE

    Zorrilla Salgador, Juan Pablo

    2004-01-01

    Segunda parte del artículo acerca del uso de futuros sobre el tipo de cambio. Esta continuación abarca estrategias, definiciones, metodología y explicaciones sobre todo lo relacionado con el Ratio de cobertura de los futuros y la aparición del riesgo base.Segunda parte del artículo acerca del uso de futuros sobre el tipo de cambio. Esta continuación abarca estrategias, definiciones, metodología y explicaciones sobre todo lo relacionado con el Ratio de cobertura de los futuros y la aparición d...

  13. Ion temperature via laser scattering on ion Bernstein waves

    International Nuclear Information System (INIS)

    Wurden, G.A.; Ono, M.; Wong, K.L.

    1981-10-01

    Hydrogen ion temperature has been measured in a warm toroidal plasma with externally launched ion Bernstein waves detected by heterodyne CO 2 laser scattering. Radial scanning of the laser beam allows precise determination of k/sub perpendicular to/ for the finite ion Larmor radius wave (ω approx. less than or equal to 2Ω/sub i/). Knowledge of the magnetic field strength and ion concentration then give a radially resolved ion temperature from the dispersion relation. Probe measurements and Doppler broadening of ArII 4806A give excellent agreement

  14. Ion Accelerator Merges Several Beams

    Science.gov (United States)

    Aston, G.

    1984-01-01

    Intense ion beam formed by merging multiple ion beamlets into one concentrated beam. Beamlet holes in graphite screen and focusing grids arranged in hexagonal pattern. Merged beam passes through single hole in each of aluminum accelerator and decelerator grids. Ion extraction efficiency, beam intensity, and focusing improved.

  15. Gerencia del servicio

    Directory of Open Access Journals (Sweden)

    Nancy Peña Acosta

    1992-02-01

    Full Text Available Estamos en la era de la pirámide invertida donde el cliente es primero por lo que es fundamental incentivar la calidad desde abajo; hacer que el trabajador defina su misión, sienta que es parte de la compañía para que la satisfacción del negocio realizado sea de todos.

  16. Punctualizaciones del CERN

    CERN Document Server

    2002-01-01

    "Viene de la pagina anterior. Puntualizaciones del CERN. La valoracion que me merece la aprobacion en el Consejo de Ministros el 24 de mayo de un acuerdo de colaboracion entre el MCYT y el CERN para el proyecto de neutrinos al Gran Sasso es positiva" (1 page).

  17. Puerta del Sol, Madrid

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2012-01-01

    Professor Eric Corijn (Vrije Universiteit Brussel) og hans virke som dynamisk urbanist blev sat i scene, da 4Cities-masterprogrammet (4Cities.eu) underviste i Madrid midt under bosættelsen på pladsen Puerta del Sol i maj 2011. Artiklen tematiserer forbindelsen mellem det sociale og rumlige liv på...

  18. Nota del Editor

    OpenAIRE

    De Giusti, Armando Eduardo

    2013-01-01

    Descripción del número 11 de la Revista Iberoamericana de Tecnología en Educación y Educación en Tecnología. Compuesta por once trabajos que han sido seleccionados luego de una cuidadosa evaluación por pares, entre 32 trabajos presentados a la revista.

  19. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2014-12-01

    Full Text Available La publicación se centra en temas como: Procesos electorales en México e Italia, se analizan los procesos comunicacionales y sus efectos; las infiltraciones de las agencias de seguridad en la actividad periodística en Europa; la radio y la televisión pública en los EE.UU. Para conocer cómo la prensa enfrenta los problemas críticos entre países, esta el caso de Uruguay y Argentina (discrepancia por la planta de procesamiento de papel y la contaminación del Río de La Plata. Otro artículo refiere la difícil relación entre los medios de comunicación y el gobierno de Chávez en Venezuela. Se aborda el caso brasileño para entender el crecimiento de los Observatorios de Medios; otro sobre el crecimiento del "periodismo confidencial" en la web y la prensa gratuita. Se estudia el impacto de la telenovela "pasión de gavilanes". Para quienes interese la penetración del Internet está: "Usos y competencias del weblog en las corporaciones" más otro sobre la lucha sorda que mantienen los gigantes de la autopista de la información Google y Yahoo.

  20. del's Proof

    Indian Academy of Sciences (India)

    /fulltext/reso/012/02/0059-0070. Keywords. Gödel; mathematical logic; group theory; set of axioms; set theory; number theory. Author Affiliations. S M Srivastava1. Stat-Math Unit Indian Statistical Institute 203, BT Road Kolkata 700 108, India.

  1. Marketing Mix del Software.

    Directory of Open Access Journals (Sweden)

    Yudith del Carmen Rodríguez Pérez

    2006-03-01

    Por ello, en este trabajo se define el concepto de producto software, se caracteriza al mismo y se exponen sus atributos de calidad. Además, se aborda la mezcla de marketing del software necesaria y diferente a la de otros productos para que este triunfe en el mercado.

  2. El Juego del Juego

    OpenAIRE

    Carvalho, Nazaré Cristina

    2012-01-01

    DUVIGNAUD, Jean. El Juego del Juego. Santafé de Bogotá, Colômbia: Fondo de Cultura Econômica, 1997.The game gameDUVIGNAUD, Jean. The Game Game. Santafé de Bogotá, Colombia: Fondo de Cultura Econômica, 1997

  3. Balanite Egyptiaca Del.

    African Journals Online (AJOL)

    ADOWIE PERE

    2018-03-23

    Mar 23, 2018 ... Molluscicidal Activity of Aqueous Extract of Leaves, Stem Back and Roots of Desert date (Balanite Egyptiaca Del.) against common Liver Fluke (Fasciola Hepatica) found in the Snail (Lymnea natalensis). 1*. ABDULLAHI, Y;. 2. MUHAMMAD, I;. 3. YERIMA, MI. 1Department of Biological Sciences, Federal ...

  4. Gerencia del servicio

    OpenAIRE

    Nancy Peña Acosta

    1992-01-01

    Estamos en la era de la pirámide invertida donde el cliente es primero por lo que es fundamental incentivar la calidad desde abajo; hacer que el trabajador defina su misión, sienta que es parte de la compañía para que la satisfacción del negocio realizado sea de todos.

  5. Rumbos actuales del arte

    Directory of Open Access Journals (Sweden)

    Luis Vidales

    1964-01-01

    Full Text Available Si se nos preguntase cual podría ser la síntesis de los problemas actuales del arte, acaso deberíamos decir que no hay nada que la exprese tan cabalmente como la lucha por los espacios plásticos. Y agregar que este fenómeno no es privativo de nuestro tiempo.

  6. del's Proof

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 5. Gödel's Proof - Incompleteness Theorems. S M Srivastava. General Article Volume 12 Issue 5 May 2007 pp 71-84. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/012/05/0071-0084. Keywords.

  7. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Gino Lofredo

    2015-01-01

    Full Text Available Presenta el análisis de 16 colaboradores que constituye un diagnóstico regional de los medios y las comunicaciones. Se ve evidente la crisis de los medios. Otro artículo trata del cine la política y la integración cultural.

  8. Evaluation of the susceptibility to pitting corrosion of steel api 5L x42 exposed to solutions containing chloride ions and CO{sub 2} by electrochemical noise measurements; Evaluacion de la susceptibilidad a la corrosion por picado del acero api 5l x42 expuesto a un ambiente con cloruros y CO{sub 2} mediante la tecnica de ruido electroquimico

    Energy Technology Data Exchange (ETDEWEB)

    Pena-Ballesteros, D.; Rodriguez-Vanegas, N.; Anteliz, C.; Sarmiento Klapper, H.

    2011-07-01

    The concentration of chloride ions and the partial pressure of CO{sub 2} play an important role in the degradation of low-carbon steels used for the construction of pipelines in oil and gas industry. In order to evaluate the susceptibility of carbon steel API 5L X42 to pitting corrosion electrochemical noise and linear polarization resistance measurements were carried out in aqueous solutions containing chloride ions and CO{sub 2}. The concentration of chloride ions was varied between, 10000 and 18000 ppm, and the CO{sub 2} partial pressure between 10 psi and 18 psi. Experimental results pointed out that the formation of protective layer, consisting mainly of FeCO{sub 3}, depends on the partial pressure of CO{sub 2} in the system. Nevertheless, the stability of this layer was considerably affected by increasing the concentration of chloride ions causing that localized corrosion has taken place in some areas of the surface of API 5L X42, which were detected by electrochemical noise technique. (Author) 10 refs.

  9. Production of highly charged ion beams from ECR ion sources

    International Nuclear Information System (INIS)

    Xie, Z.Q.

    1997-09-01

    Electron Cyclotron Resonance (ECR) ion source development has progressed with multiple-frequency plasma heating, higher mirror magnetic fields and better technique to provide extra cold electrons. Such techniques greatly enhance the production of highly charged ions from ECR ion sources. So far at cw mode operation, up to 300 eμA of O 7+ and 1.15 emA of O 6+ , more than 100 eμA of intermediate heavy ions for charge states up to Ar 13+ , Ca 13+ , Fe 13+ , Co 14+ and Kr 18+ , and tens of eμA of heavy ions with charge states to Kr 26+ , Xe 28+ , Au 35+ , Bi 34+ and U 34+ have been produced from ECR ion sources. At an intensity of at least 1 eμA, the maximum charge state available for the heavy ions are Xe 36+ , Au 46+ , Bi 47+ and U 48+ . An order of magnitude enhancement for fully stripped argon ions (I ≥ 60 enA) also has been achieved. This article will review the ECR ion source progress and discuss key requirement for ECR ion sources to produce the highly charged ion beams

  10. Determinantes del ingreso y del gasto corriente de los hogares

    Directory of Open Access Journals (Sweden)

    Muñoz C., Manuel

    2004-06-01

    Full Text Available Este ensayo de investigación empírica analiza los determinantes del ingreso y del gasto en los hogares colombianos. Utilizando un modelo del ciclo de vida con datos de la encuesta de hogares de 1994 y 1995, muestra que el comportamiento del ingreso está afectado principalmente por las características demográficas del hogar y los rasgos socio ocupacionales de sus miembros. El comportamiento del gasto está determinado ante todo por el ingreso y, en menor medida, por las características sociales del hogar y el gasto de otros hogares con características similares. También examina la influencia de la incertidumbre acerca de los ingresos en el gasto de los hogares para comprobar si estos actúan con motivos de precaución.

  11. Production of highly ionized recoil ions in heavy ion impact

    International Nuclear Information System (INIS)

    Tawara, H.; Tonuma, T.; Be, S.H.; Shibata, H.; Kase, M.; Kambara, T.; Kumagai, H.; Kohno, I.

    1985-01-01

    The production mechanisms of highly ionized recoil ions in energetic, highly charged heavy ion impact are compared with those in photon and electron impact. In addition to the innershell ionization processes which are important in photon and electron impact, the electron transfer processes are found to play a key role in heavy ion impact. In molecular targets are also observed highly ionized monoatomic ions which are believed to be produced through production of highly ionized molecular ions followed by prompt dissociation. The observed N 6+ ions produced in 1.05MeV/amu Ar 12+ ions on N 2 molecules are produced through, for example, N 2 12+ *→N 6+ +N 6+ process. (author)

  12. Tissue molecular ion imaging by gold cluster ion bombardment.

    Science.gov (United States)

    Touboul, David; Halgand, Fréderic; Brunelle, Alain; Kersting, Reinhard; Tallarek, Elke; Hagenhoff, Birgit; Laprévote, Olivier

    2004-03-15

    The use of gold cluster focused ion beams produced by a liquid metal ion gun in a TOF-SIMS mass spectrometer is shown to dramatically enhance secondary ion emission of phospholipids and peptides. The method has been successfully tested with cells grown onto plastic slips and with mouse brain slices, without any treatment of the samples. Very reliable time-of-flight mass spectra are acquired with a low primary ion dose of a few 10(7) ions, and high lateral resolution molecular ion images are obtained for heavy ions of great biological interest. This approach offers new opportunities in pharmacological and biological research fields by localizing compounds of interest such as drugs or metabolites in tissues.

  13. A laser ablation ion source for the FRS ion catcher

    Energy Technology Data Exchange (ETDEWEB)

    Rink, Ann-Kathrin; Ebert, Jens; Petrick, Martin; Reiter, Pascal [Justus Liebig Universitaet Giessen (Germany); Dickel, Timo; Geissel, Hans; Plass, Wolfgang; Scheidenberger, Christoph [Justus Liebig Universitaet Giessen (Germany); GSI, Darmstadt (Germany); Purushothamen, Sivaji [GSI, Darmstadt (Germany)

    2013-07-01

    The FRS Ion Catcher was developed to serve as test bench for the low energy branch of the Super FRS to slow down exotic nuclei and prepare them for further measurements/ experiments. It consists of a cryogenic stopping cell to thermalise the ions, a diagnostic unit for stopping cell characterisation and various radiofrequency quadrupole structures to guide the ions to the Multiple-Reflection Time-of-Flight Mass Spectrometer for mass measurements, α spectroscopy and isobar separation. To characterise the extraction times of the stopping cell, which is one of the main performance parameters of such a cell, a laser ablation ion source has been develped and tested. This ion source provides a sharply defined starting point of the ions for the extraction time measurement. In the future this source will provide reference ions to calibrate the mass spectrometer for accurate mass measurements.

  14. Ion microtomography using ion time-of-flight

    International Nuclear Information System (INIS)

    Roberts, M.L.; Heikkinen, D.W.; Proctor, I.D.; Pontau, A.E.; Olona, G.T.; Felter, T.E.; Morse, D.H.; Hess, B.V.

    1992-01-01

    We have developed and are in the process of testing an ion time-of-flight (TOF) detector system for use in our ion microtomography measurements. Using TOF, ion energy is determined by measurement of the ion's flight time over a certain path length. For ion microtomography, the principle advantage of TOF analysis is that ion count rates of several hundred thousand counts per second can be achieved as compared to a limit of about ten thousand ions per second when using a solid-state silicon surface barrier detector and associated electronics. This greater than 10 fold increase in count rate correspondingly shortens sample analysis time or increases the amount of data that can be collected on a given sample. Details of the system and progress to date are described

  15. Design study of primary ion provider for relativistic heavy ion collider electron beam ion source.

    Science.gov (United States)

    Kondo, K; Kanesue, T; Tamura, J; Okamura, M

    2010-02-01

    Brookhaven National Laboratory has developed the new preinjector system, electron beam ion source (EBIS) for relativistic heavy ion collider (RHIC) and National Aeronautics and Space Administration Space Radiation Laboratory. Design of primary ion provider is an essential problem since it is required to supply beams with different ion species to multiple users simultaneously. The laser ion source with a defocused laser can provide a low charge state and low emittance ion beam, and is a candidate for the primary ion source for RHIC-EBIS. We show a suitable design with appropriate drift length and solenoid, which helps to keep sufficient total charge number with longer pulse length. The whole design of primary ion source, as well as optics arrangement, solid targets configuration and heating about target, is presented.

  16. Ion bipolar junction transistors.

    Science.gov (United States)

    Tybrandt, Klas; Larsson, Karin C; Richter-Dahlfors, Agneta; Berggren, Magnus

    2010-06-01

    Dynamic control of chemical microenvironments is essential for continued development in numerous fields of life sciences. Such control could be achieved with active chemical circuits for delivery of ions and biomolecules. As the basis for such circuitry, we report a solid-state ion bipolar junction transistor (IBJT) based on conducting polymers and thin films of anion- and cation-selective membranes. The IBJT is the ionic analogue to the conventional semiconductor BJT and is manufactured using standard microfabrication techniques. Transistor characteristics along with a model describing the principle of operation, in which an anionic base current amplifies a cationic collector current, are presented. By employing the IBJT as a bioelectronic circuit element for delivery of the neurotransmitter acetylcholine, its efficacy in modulating neuronal cell signaling is demonstrated.

  17. Trapped Ion Qubits

    Energy Technology Data Exchange (ETDEWEB)

    Maunz, Peter Lukas Wilhelm

    2017-04-01

    Qubits can be encoded in clock states of trapped ions. These states are well isolated from the environment resulting in long coherence times [1] while enabling efficient high-fidelity qubit interactions mediated by the Coulomb coupled motion of the ions in the trap. Quantum states can be prepared with high fidelity and measured efficiently using fluorescence detection. State preparation and detection with 99.93% fidelity have been realized in multiple systems [1,2]. Single qubit gates have been demonstrated below rigorous fault-tolerance thresholds [1,3]. Two qubit gates have been realized with more than 99.9% fidelity [4,5]. Quantum algorithms have been demonstrated on systems of 5 to 15 qubits [6–8].

  18. Negative ion sourcery

    International Nuclear Information System (INIS)

    Os, C.F.A. van.

    1989-01-01

    The work described in this thesis is involved by current research programs in the field of nuclear-fusion. A brief introduction to fusion is given, anticipated problems related to current drive of the fusion plasma are pinpointed and probable suggestions to overcome these problems are described. One probable means for current drive is highlighted; Neutral Beam Injection (NBI). This is based on injecting a 1 MeV neutral hydrogen or deuterium beam into a fusion plasma. Negative ions are needed as primary particles because they can easily be neutralized at 1 MeV. The two current schemes for production of negative ions are described, volume production and negative surface ionization. The latter method is extensively studied in this thesis. (author). 171 refs.; 55 figs.; 7 tabs

  19. Experimental Evaluation of a Negative Ion Source for a Heavy Ion Fusion Negative Ion Driver

    Energy Technology Data Exchange (ETDEWEB)

    Grisham, L. R.; Hahto, S. K.; Hahto, S. T.; Kwan, J. W.; Leung, K. N.

    2004-06-16

    Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photo-detached to neutrals. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 45 mA/cm{sup 2} of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that i s used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl{sup -} was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 45 mA/cm{sup 2}, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

  20. Ion funnel device

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Yehia M.; Chen, Tsung-Chi; Harrer, Marques B.; Tang, Keqi; Smith, Richard D.

    2017-11-21

    An ion funnel device is disclosed. A first pair of electrodes is positioned in a first direction. A second pair of electrodes is positioned in a second direction. The device includes an RF voltage source and a DC voltage source. A RF voltage with a superimposed DC voltage gradient is applied to the first pair of electrodes, and a DC voltage gradient is applied to the second pair of electrodes.

  1. Ion optics for accelerators

    International Nuclear Information System (INIS)

    Enge, H.A.

    1974-01-01

    A review is given of ion-optic devices used in particle accelerators, including electrostatic lenses, magnetic quadrupoles, and deflecting magnets. Tube focusing in dc accelerators is also treated, and a novel scheme for shaping the electrodes to produce strong focusing is described. The concepts of emittance (phase space) and emittance conservation are briefly discussed. Chromatic and spatial aberrations are introduced, and it is shown how they can be calculated and sometimes substantially reduced. Some examples are given

  2. Heavy ion fusion III

    International Nuclear Information System (INIS)

    Hammer, D.; Max, C.; Perkins, F.; Rosenbluth, M.

    1987-03-01

    This report updates Heavy Ion Fusion, JSR-82-302, dated January, 1983. During the last four years, program management and direction has been changed and the overall Inertial Confinement Program has been reviewed. This report therefore concentrates on accelerator physics issues, how the program has addressed those issues during the last four years, and how it will be addressing them in the future. 8 refs., 3 figs

  3. Collective Ion Acceleration.

    Science.gov (United States)

    1980-01-01

    flash x- _ ray sources may require, for maximum x-ray yield. t Pulsed-power systems using Van de Graaff generators are also in use. They are less common... generation and collective ion acceleration. A more recent effort has been initi- II ated to investigate proton acceleration in Induction Linacs. The...original contract supported the study of microwave generation using slow wave structures and study of a free electron laser configuration. About 1 alfway

  4. Relativistic heavy ion reactions

    International Nuclear Information System (INIS)

    Brink, D.M.

    1989-08-01

    The theory of quantum chromodynamics predicts that if nuclear matter is heated to a sufficiently high temperature then quarks might become deconfined and a quark-gluon plasma could be produced. One of the aims of relativistic heavy ion experiments is to search for this new state of matter. These lectures survey some of the new experimental results and give an introduction to the theories used to interpret them. 48 refs., 4 tabs., 11 figs

  5. Cancer therapy with ions

    International Nuclear Information System (INIS)

    Mandrillon, P.

    1993-01-01

    The treatment of tumours with charged particles, ranging from protons to 'light ions' (Carbon, Oxygen, Neon) has many advantages, but up to now has been little used because of the absence of facilities. After the successful pioneering work carried out with accelerators built for physics research, machines dedicated to this new radiotherapy are planned or already in construction. The rationale for this new radiotherapy, the accelerators and the beam delivery systems needed are presented in this paper. (orig.)

  6. Secondary ion mass spectroscopy

    International Nuclear Information System (INIS)

    Sroubek, Z.; Zavadil, J.; Kubec, F.

    1977-01-01

    Secondary ion mass spectroscopy is one of the modern methods suitable for the analysis of thin films and solid state surfaces. The method is capable of providing the compositional information with a depth resolution below 0.1 μm and a sensitivity of the order of 10 -3 ppm for some impurities. The review article contains a description of the method, a list of typical applications and a short account of relevant theories. (author)

  7. Small size ion pumps

    International Nuclear Information System (INIS)

    Cyranski, R.; Kiliszek, Cz.R.; Marks, J.; Sobolewski, A.; Magielko, H.

    2001-01-01

    This paper describes some designs of the two versions ion pumps and their range operation for various magnetic fields. The first version is made with different cell size in the anode element and titanium cathode operating in magnetic field from 600 to 650 Gs and the second version with the same anode element but differential Ti/Ta cathode working in magnetic field above 1200 Gs

  8. Intercambio cationico calcio-magnesio-sodio en algunos suelos del Valle del Cauca

    Directory of Open Access Journals (Sweden)

    Torres M. Jorge Ilian

    1989-12-01

    Full Text Available Para estudiar la influencia de diferentes cantidades de Ca, Mg y Na en las aguas de riego sobre las propiedades químicas y físicas de los suelos, se caracterizó el intercambio Ca-Mg en presencia de diferentes saturaciones de Na en la solución de equilibrio en términos de las isotemas de intercambio de 4 suelos pertenecientes a los tres principales ordenes predominantes en el Valle del Cauca. En general hubo ligera preferencia por Ca sobre Mg en los suelos; pero a bajas concentraciones de Mg en la solución el suelo Doronzoro mostró preferencia por Mg y el suelo Crucero una tendencia hacia mayor afinidad por el Mg+2a altos valores de Mg y de la RAS en la solución. Las preferencias de los suelos por Mg parecen estar asociadas en parte con la presencia de carbonatos y materia orgánica. Con excepción del suelo Crucero, las isotermas no mostraron influencia de la RAS o del PSI resultante sobre la selectividad por Ca+2 o Mg+2. Las altas saturaciones de Mg+2 encontradas en muchos suelos del Valle del Cauca se deben a la presencia de altas cantidades de este ión en las aguas de riego en las aguas freáticas y no a preferencia de los suelos por el mismo.To study the influence of different amounts of Ca, Mg and Na in the irrigation water on chemical and physical properties of soils, four soils from the Cauca Valle y were used to characterize their cation distribution and the Ca-Mg exchange in presence of different concentrations of Na in the equilibrium solution. A general preference for Ca over Mg was found; however, the Doronzoro soil isotherms showed that at low ion concentrations of Mg in the solutions there is a preference for Mg2+relative to Ca2+ and Crucero soil showed an increasing affinity to Mg2+as its concentration and SAR increase in the solution. Soil preferences for magnesium seem to be related to the presence of organic matter or to the presence of carbonates. Excluding the Crucero soil the isotherms did not show influence of SAR

  9. Diagrama de estabilidad termodinámico del sistema de flotación cobre/agua/amilxantato

    Directory of Open Access Journals (Sweden)

    Beatriz Ramírez-Serrano

    2015-05-01

    Full Text Available El propósito del trabajo fue obtener el diagrama de estabilidad termodinámico que caracteriza al sistema de flotación cobre/agua/amilxantato, como parte del fundamento teórico necesario para el análisis del proceso de flotación de iones cobre con el reactivo colector de flotación amilxantato de potasio. A partir del sistema de reacciones químicas fundamentales y con ayuda del sofware Medusa se obtuvo el diagrama Eh-pH en el cual se definen las zonas de estabilidad de las diferentes especies químicas y se establece que en el rango de pH de 4 a 13 coexisten las especies xantogenadas de cobre(I y (II cuya relación disminuye con el incremento del pH.

  10. Fluorine negative ion detachment kinetics

    Science.gov (United States)

    Burke, R. R.; Miller, W. J.; Gould, R. K.

    1971-01-01

    A study of the rate of F(-) detachment by O and H atoms via the reactions F(-) + O yields FO + e and F(-) + H yields FH+ e was undertaken using a drift tube to produce F(-) ions at various drift velocities and therefore different ion temperatures. Preliminary mobility measurements of F(-) ions in Ar were made, indicating that ion temperatures in the 300 K to 5000 K range could be achieved; however due to numerous difficulties experienced in obtaining a reliable F(-) ion source, the study could not be completed.

  11. Ion sources for medical accelerators

    Science.gov (United States)

    Barletta, W. A.; Chu, W. T.; Leung, K. N.

    1998-02-01

    Advanced injector systems for proton synchrotrons and accelerator-based boron neutron capture therapy systems are being developed at the Lawrence Berkeley National Laboratory. Multicusp ion sources, particularly those driven by radio frequency, have been tested for these applications. The use of a radio frequency induction discharge provides clean, reliable, and long-life source operation. It has been demonstrated that the multicusp ion source can provide good-quality positive hydrogen ion beams with a monatomic ion fraction higher than 90%. The extractable ion current densities from this type of source can meet the injector requirements for both proton synchrotron and accelerator-based boron neutron capture therapy projects.

  12. Recent progress in ion sources

    International Nuclear Information System (INIS)

    Osher, J.E.

    1975-01-01

    This paper is intended to survey recent developments in ion sources, particularly work reported at the ''Symposium on Ion Sources and the Formation of Ion Beams'' held in Berkeley in October 1974. The approach here will be to subdivide this topic into three main areas; briefly list and discuss notable progress in each; and finally add some additional detail through a few specific, selected examples. The major items of progress discussed include development of large-area plasma surfaces for multiple- aperture ion sources, a significant increase in available negative-ion current densities, and improved general agreement between extraction electrode design and performance. (U.S.)

  13. High energy ion microprobes

    International Nuclear Information System (INIS)

    Nobiling, R.

    1983-01-01

    Analysis with high energy ion beams can be applied to microscopic samples or substructures of complex specimens by using nuclear or proton microprobes. Focusing of high energy ion beams requires specially designed collimators and lens systems. At present, beam diameters of 1 μm are obtained. The lateral resolution of the instruments, however, is not limited to this 1 μm. Consequently microprobe analysis with ion beams in favourable cases can provide better analytical possibilities and lateral resolution as compared with electron microprobes. Due to aberrations an improvement of beam diameters to less than 0.5-1 μm requires compensation of at least the chromatic aberration. The most important fields of application are mineralogy, materials science and biology. With nuclear reactions and PIXE (particle induced X-ray emission) the whole periodic table can be measured with detection limits down to the ppm level (weight fraction). The virtual lack of beam broadening by scattering in samples of a few μm thickness makes a kind of microscopic chemical tomography possible. (orig.)

  14. Novel laser ion sources

    CERN Document Server

    Fournier, P; Kugler, H; Lisi, N; Scrivens, R; Rodríguez, F V; Düsterer, S; Sauerbrey, R; Schillinger, H; Theobald, W; Veisz, L; Tisch, J W G; Smith, R A

    2000-01-01

    Development in the field of high-power laser systems with repetition rates of several Hz and energies of few joules is highly active and opening, giving new possibilities for the design of laser ions sources. Preliminary investigations on the use of four different laser and target configurations are presented: (1) A small CO/sub 2/ laser (100 mJ, 10.6 mu m) focused onto a polyethylene target to produce C ions at 1 Hz repetition rate (CERN). (2) An excimer XeCl laser (6 J, 308 nm) focused onto solid targets (Frascati). (3) A femtosecond Ti: sapphire laser (250 mJ, 800 nm) directed onto a solid targets (Jena). (4) A picosecond Nd: yttrium-aluminum-garnet (0.3 J, 532 nm) focused into a dense medium of atomic clusters and onto solid targets (London). The preliminary experimental results and the most promising schemes will be discussed with respect to the scaling of the production of high numbers of highly charged ions. Different lasers are compared in terms of current density at 1 m distance for each charge state...

  15. Ion channeling revisited

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, Barney Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Corona, Aldo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nguyen, Anh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    A MS Excel program has been written that calculates accidental, or unintentional, ion channeling in cubic bcc, fcc and diamond lattice crystals or polycrystalline materials. This becomes an important issue when simulating the creation by energetic neutrons of point displacement damage and extended defects using beams of ions. All of the tables and graphs in the three Ion Beam Analysis Handbooks that previously had to be manually looked up and read from were programed into Excel in handy lookup tables, or parameterized, for the case of the graphs, using rather simple exponential functions with different powers of the argument. The program then offers an extremely convenient way to calculate axial and planar half-angles and minimum yield or dechanneling probabilities, effects on half-angles of amorphous overlayers, accidental channeling probabilities for randomly oriented crystals or crystallites, and finally a way to automatically generate stereographic projections of axial and planar channeling half-angles. The program can generate these projections and calculate these probabilities for axes and [hkl] planes up to (555).

  16. Ion Acceleration Inside Foreshock Transients

    Science.gov (United States)

    Liu, Terry Z.; Lu, San; Angelopoulos, Vassilis; Lin, Yu; Wang, X. Y.

    2018-01-01

    Recent observations upstream of Earth's bow shock have revealed that foreshock transients can not only accelerate solar wind ions by reflection at their upstream boundaries but may also accelerate ions inside them. Evidence for the latter comes from comparisons of ion spectra inside and outside the cores, and from evidence of leakage of suprathermal ions from the cores. However, definite evidence for, and the physics of, ion acceleration in the foreshock transients are still open questions. Using case studies of foreshock transients from Time History of Events and Macroscale Interactions during Substorms observations, we reveal an ion acceleration mechanism in foreshock transients that is applicable to 25% of the transients. The ion energy flux is enhanced between several keV to tens of keV in the cores. We show that these energetic ions are reflected at the earthward moving boundary of foreshock transients, are accelerated through partial gyration along the convection electric field, and can leak out both upstream and downstream of the foreshock transients. Using ions moving self-consistently with a generic 3-D global hybrid simulation of a foreshock transient, we confirm this physical picture of ion acceleration and leakage. These accelerated ions could be further accelerated at the local bow shock and repopulate the foreshock, increasing the efficacy of solar wind-magnetosphere interactions.

  17. Resonance Ionization Laser Ion Sources

    CERN Document Server

    Marsh, B

    2013-01-01

    The application of the technique of laser resonance ionization to the production of singly charged ions at radioactive ion beam facilities is discussed. The ability to combine high efficiency and element selectivity makes a resonance ionization laser ion source (RILIS) an important component of many radioactive ion beam facilities. At CERN, for example, the RILIS is the most commonly used ion source of the ISOLDE facility, with a yearly operating time of up to 3000 hours. For some isotopes the RILIS can also be used as a fast and sensitive laser spectroscopy tool, provided that the spectral resolution is sufficiently high to reveal the influence of nuclear structure on the atomic spectra. This enables the study of nuclear properties of isotopes with production rates even lower than one ion per second and, in some cases, enables isomer selective ionization. The solutions available for the implementation of resonance laser ionization at radioactive ion beam facilities are summarized. Aspects such as the laser r...

  18. ABC del Ajedrez. I

    Directory of Open Access Journals (Sweden)

    Marisel Piñeiro Gomez

    2009-03-01

    Full Text Available La promoción del Ajedrez, su conocimiento y práctica por la población constituye uno de los programas de la Revolución, por tal motivo el presente trabajo está encaminado a proponer un material bibliográfico con variadas posiciones sobre el movimiento-captura de las piezas y los sistemas de notación para los masificadores de Ajedrez del municipio Pinar del Río. En esta investigación se utilizaron variados métodos: teóricos, empíricos y estadísticos, además, como método rector el dialéctico materialista. Constituye una novedad científica porque aporta un material bibliográfico que contiene: la composición,  disposición  e  identificación  del  tablero de  ajedrez;  identificación, colocación, movimiento y captura de las piezas de ajedrez; la promoción del Peón; el valor absoluto de las piezas; los sistemas de notación: descriptivo y algebraico. Se le incluyen más de trescientos gráficos, conceptos que son trabajados de lo simple a lo complejo de manera tal que el masificador de Ajedrez lo utilice en sus clases donde se viabilice el conocimiento gracias a las facilidades que le aporta el material; ofrece algoritmos que le guiarán a elaborar nuevas posiciones, los cuales son inexistentes para este propósito en otras bibliografías; su significación práctica radica en que proporciona, tanto al estudiantado como profesorado, ejercicios de ajedrez sencillos que les permitirá a los primeros para que les sirva en su comportamiento, y a los segundos utilizarlos en su auto preparación; el interés social se halla en que pueden ser utilizados por profesores, personal de apoyo a la docencia,  técnicos  del  INDER,  familiares  de  los  estudiantes  para  ayudarlos;  el interés educativo reside en que a través de esos ejercicios contribuimos al fortalecimiento de valores.

  19. A review of polarized ion sources

    International Nuclear Information System (INIS)

    Schmor, P.W.

    1995-06-01

    The two main types of polarized ion sources in use on accelerators today are the Atomic Beam Polarized Ion Source (ABIS) source and the Optically Pumped Polarized Ion Source (OPPIS). Both types can provide beams of nuclearly polarized light ions which are either positively or negatively charged. Heavy ion polarized ion sources for accelerators are being developed. (author). 35 refs., 1 tab

  20. ION SOURCES FOR ENERGY EXTREMES OF ION IMPLANTATION.

    Energy Technology Data Exchange (ETDEWEB)

    HERSCHCOVITCH,A.; JOHNSON, B.M.; BATALIN, V.A.; KROPACHEV, G.N.; KUIBEDA, R.P.; KULEVOY, T.V.; KOLOMIETS, A.A.; PERSHIN, V.I.; PETRENKO, S.V.; RUDSKOY, I.; SELEZNEV, D.N.; BUGAEV, A.S.; GUSHENETS, V.I.; LITOVKO, I.V.; OKS, E.M.; YUSHKOV, G. YU.; MASEUNOV, E.S.; POLOZOV, S.M.; POOLE, H.J.; STOROZHENKO, P.A.; SVAROVSKI, YA.

    2007-08-26

    For the past four years a joint research and development effort designed to develop steady state, intense ion sources has been in progress with the ultimate goal to develop ion sources and techniques, which meet the two energy extreme range needs of mega-electron-volt and 100's of electron-volt ion implanters. This endeavor has already resulted in record steady state output currents of high charge state of Antimony and Phosphorous ions: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb{sup 4+}, Sb{sup 5+}, and Sb{sup 6+} respectively. For low energy ion implantation our efforts involve molecular ions and a novel plasmaless/gasless deceleration method. To date, 1 emA of positive Decaborane ions were extracted at 10 keV and smaller currents of negative Decaborane ions were also extracted. Additionally, Boron current fraction of over 70% was extracted from a Bemas-Calutron ion source, which represents a factor of 3.5 improvement over currently employed ion sources.

  1. Estimacion del modulo de elasticidad del concreto y del mortero mediante TCTM

    OpenAIRE

    Quimbay Herrera, Rodrigo

    2012-01-01

    El Modulo de Elasticidad del concreto o Modulo de Young es considerado uno de los mas importantes parámetros en el diseño y construcción de estructuras de concreto reforzado. El Modulo de Elasticidad se calcula a 0.45 de la f’c como la pendiente secante del diagrama esfuerzo y deformación unitaria, y en el caso del concreto el valor aumenta con el tiempo dependiendo de la resistencia, por lo que es dependiente del concreto en particular. En general a mayor resistencia del concreto y mayor den...

  2. Arco del milenio

    Directory of Open Access Journals (Sweden)

    Adell, Josep Mª

    2005-02-01

    the most significant stages in the erection of the Millennium Arch outside the Palacio de Congresos, venue for the 12th IBMAC.
    These pictures are divided into six chapters: Background, Components, Springline, Piers, Arch, Centring Erection and Removal, and Trimming.

    A lo largo de la historia, el Arco de fábrica ha sido el componente constructivo más característico de la Arquitectura y la Ingeniería desde que después de sus inicios etruscos en la época romana fuera desarrollado adelantándose con ello a la cultura helénica.
    El Arco, desde entonces, viene empleándose como una solución constructiva eficiente para cubrir espacios con materiales que no soportan tracciones. La originalidad técnica del Arco lo ha llevado a imponerse como símbolo de las hazañas bélicas como era el Arco de Triunfo.
    En el cambio de siglo y milenio en el que nos encontramos, un salto técnico fundamental se desvela en este Congreso, el Sistema de Albañilería Integral, que abre la posibilidad de ampliar el campo de aplicación de la albañilería con la incorporación del acero, a través de las perforaciones de las piezas, lográndose por fin armar en las tres direcciones del espacio cualquier muro de fábrica que se desee.
    El Arco del Milenio conmemoró el 12th IBMAC de Madrid, mostrando en él los avances técnicos que el Sistema de Albañilería Integral permite, al tratarse de un arco inclinado en el espacio y, por tanto, el primer arco de fábrica construido fuera de la vertical, mediante fábrica de Ladriflor aparejada a tizón, reforzada con barras y cercos.
    El Arco del Milenio, diseñado por J.M. Adell (Presidente del 12th IBMAC, parte de un cilindro de 14 m de diámetro, inclinado 30º sobre el terreno, y construido con fábrica de ladrillo de un pie de grueso, alternando una hilada de color amarillo de cada seis en rojo. El hueco deja un paso libre de 10 m de lado y 5,5 m de altura. La fábrica está armada regularmente por tendeles con cerchas cada

  3. del consumidor mexicano

    Directory of Open Access Journals (Sweden)

    Nadia Huitzilin Jiménez Torres

    2013-01-01

    Full Text Available Pese a que el 80% de la población del mundo vive en mercados emergentes y países en desarrollo, como México, la investigación sobre el consumidor de estos países ha sido insuficiente. El objetivo de este estudio es determinar el perfil del consumidor mexicano en función de variables psicosociológicas como el etnocentrismo, la apertura cultural, el patriotismo, el colectivismo y las características demográficas. Con este propósito se recogió la información de una muestra de 274 consumidores, se realizaron un análisis factorial de sus principales componentes y un análisis cluster con el cual se aglomeró a los individuos en tres grupos con diferentes perfiles psicosociológicos y demográficos.

  4. Las cruces del olvido

    Directory of Open Access Journals (Sweden)

    Carla Fernandes

    2012-08-01

    Full Text Available Les tragiques événements du « mars paraguayen » ont signifié la disparition de l’espoir en la transition démocratique dans laquelle le pays s’était engagé depuis presque une dizaine d’années. Renée Ferrer, poète, dramaturge, auteur de plusieurs recueils de contes et de deux romans, consigne alors le témoignage poétique de ce drame national dans le recueil Las cruces del olvido (2001. Elle a auparavant publié d’autres textes qui peuvent rentrer dans la catégorie de la poésie sociale : c’est le cas en particulier de Viaje a destiempo (1989 dédié aux victimes de la dictature. Las cruces del olvido, dès son paratexte, insiste sur la fonction de témoignage que l’auteur souhaite assigner à ses vers et sur le rôle que ceux-ci peuvent jouer dans la transmission d’une mémoire collective. La voix d’un jeune disparu de ce « mars paraguayen », le dédoublement qu’il subit et travers lequel il évoque son entrée dans la mort et son absence du monde des vivants, rendent possible l’écriture de cette expérience de l’indicible qu’est la disparition.Los trágicos acontecimientos del «marzo paraguayo» significaron la desaparición de la esperanza en la transición democrática que el país está viviendo desde unos diez años. Renée Ferrer, poeta, dramaturga, autora de varios libros de cuentos y de dos novelas, escribe entonces el testimonio poético de ese drama nacional en su poemario Las cruces del olvido (2001. Ya había publicado antes textos que se pueden considerar como poesía social: es el caso de Viaje a destiempo (1989 dedicado a las víctimas de la dictadura. Desde el texto apertural, Las cruces del olvido potencia la función de testimonio que la autora desea conceder a sus versos y el papel que éstos pueden desempeñar en la transmisión de una memoria colectiva. La voz de un joven desaparecido del «marzo paraguayo», el desdoblamiento que sufre y a través del cual evoca su entrada en la

  5. Infecciones del tracto urinario

    Directory of Open Access Journals (Sweden)

    K. Andrés Wurgaft, Dr.

    2010-07-01

    Full Text Available La infección del tracto urinario (ITU, con sus múltiples presentaciones clínicas, está entre las enfermedades infecciosas más frecuentes, tanto en pacientes ambulatorios como hospitalizados. El uso del examen de orina completa y de urocultivo debe ser racional. La bacteriuria asintomática no debe ser buscada ni tratada, en parte porque esto favorece el desarrollo de bacterias resistentes a antibióticos. Distintos cuadros clínicos requieren de distintas duraciones de terapia antibiótica, y tanto el exceso de días de tratamiento como su falta deben evitarse. Se requiere investigación en la búsqueda de estrategias más efectivas para prevenir las ITU recurrentes y en el desarrollo de nuevos antibióticos orales para las ITU resistentes.

  6. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available Desde la perspectiva del proceso de la comunicación, en el que el mensaje juega un papel determinante para la victoria electoral, trata la campaña presidencial de Fox en México. Se aborda el tema de ética y comunicación. Sobre la base de la experiencia española, se responde a si los sondeos electorales son un instrumento confiable para aquilatar las diferentes corrientes de opinión pública. Buscando explicaciones para el impacto que tuvo la telenovela Betty la fea se analiza este fenómeno. Otros temas relevantes son: Cómo escribir en Internet, Mecanismos que despliega la radiodifusión para renovar su programación y lograr captar y mantener una mayor audiencia y, en el lenguaje periodístico el buen uso del gerundio.

  7. Los misterios del dinero

    Directory of Open Access Journals (Sweden)

    Elena Esposito

    2013-01-01

    Full Text Available El presente artículo aborda los problemas relativos a la comprensión del dinero en la sociedad moderna. En la actualidad no existe una teoría sociológica adecuada para comprender las funciones y especificidades del dinero. Frente a esto el presente artículo se propone comprender al dinero en el contexto de una dimensión temporal, específicamente como un "medio de aplazamiento". Se abordan a continuación algunas consecuencias de la monetarización de la economía de la sociedad y se analizan algunas características de la economía de los "derivados". El artículo concluye con consideraciones relativas al nuevo carácter de la economía monetaria.

  8. Responsabilidad Constitucional del Gobierno

    Directory of Open Access Journals (Sweden)

    Francisco Zúñiga Urbina

    2006-01-01

    Full Text Available El artículo analiza la responsabilidad constitucional del Gobierno y sostiene que es jurídico-política, de lejano cuño penal y administrativo, y el procedimiento empleado para hacerla efectiva es la acusación en juicio político, que es un típico caso de "justicia política". A la responsabilidad constitucional se suman las responsabilidades civil y penal de Derecho Público del Presidente de la República y sus ministrosThis paper analyses constitutional responsibility of the government and sustains that it is political and juridical, of distant penal and administrative inspiration, and that the procedure used for persecution is impeachment in political trials, demonstrating a typical case of "political justice." Added to the constitutional responsibility of the government are the civil and penal responsibilities of the President and minister's public law

  9. Le forme del fondo

    Directory of Open Access Journals (Sweden)

    Michel Maffesoli

    2004-12-01

    Full Text Available Non è vero che la natura ha paura del vuoto. Forse addirittura si completa. Il vuoto è anche una modalità dell'essere. È possibile nidificarvisi, avvolgersi pigramente e, così, proteggersi dall'angoscia del tempo che passa. Il vuoto delle apparenze è, in alcuni momenti, una delle forme d'espressione della vita sociale. Oltretutto occorre saperle riconoscere. Certamente, abbiamo tutti un'esistenza personale, ma siamo, ugualmente, i rappresentanti, a volte anche le vittime, di uno "spirito comune", forse anche di un "inconscio collettivo" che si è costituito di secolo in secolo. E, molto spesso, quando crediamo di esprimere le nostre idee, siamo soltanto dei portavoce, comparse di un vasto "theatrum mundi" dalle dimensioni infinite.

  10. Sonidos del Silencio

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    Luz Rodríguez Carranza

    2009-12-01

    Full Text Available La novela ha muerto, afirmaba Alberto Moravia, popularizada, anexada y banalizada por el cine, la televisión, la prensa, la sicología y la sociología. Para Carlos Fuentes en cambio - quien cita a Moravia en 1969 – « lo que ha muerto es sólo la forma burguesa de la novela, el realismo » (17. Basta un viaje rápido por la red para verificar, sin embargo, que la víctima goza de buena salud y que no está confinada en la cultura de masas o en las ciencias sociales : el modelo realista del siglo XIX – y particularmente la creación de tipos representativos de una época, sean éstos promediales o excepcionales - constituye aún la principal preocupación de los escritores y críticos literarios del siglo XXI.

  11. Carta del editor

    Directory of Open Access Journals (Sweden)

    José Sánchez Gutiérrez

    2018-01-01

    Full Text Available La comunicación científica en México vive enormes retos ante la carrera de adaptar sus formas de comunicación a las nuevas tecnologías. No es tarea fácil convencerse de abandonar el papel y la imprenta para apostar por el código abierto. Sin embargo, esto es apremiante debido al retraso que se lleva en comparación con otras regiones.  Un reto muy evidente ha sido comprender el acceso abierto, reconociendo que este permite mayor visibilidad a la ciencia y que ayuda a evitar el plagio.  Razón por la que nos alegra que a partir del número 37, Mercados y Negocios cuenta con el ISSN electrónico, además del impreso

  12. RESPONSABILIDAD DEL ODONTOPEDIATRA

    OpenAIRE

    Guillen B., Celso

    2014-01-01

    La Responsabilidad de la atención del niño, requiere de una formación y preparación universitaria de la Segunda Especialidad en Odontopediatría para manejar organismos en proceso de crecimiento somático y psicológico. Es por eso que con el proceso de la ciencia se ha comprendido la importancia de la atención del niño desde que nace. Es así que se ha creado sistemas integrales de atención odontopediátrica durante los primeros años de vida, debido a la alta vulnerabilidad de contraer las enferm...

  13. Los oficios del comunicador

    Directory of Open Access Journals (Sweden)

    Jesús Martín-Barbero

    2011-01-01

    Full Text Available En el presente ensayo se evalúan los oficios del comunicador a la luz de tres ámbitos problemáticos: las competencias y los oficios, las agencias de legitimación y las dinámicas de transformación. Se defiende la tesis de un cambio cualitativo, desde un comunicador-intermediario hacia un comunicador-mediador, que asume como base de su acción las asimetrías y las desigualdades sociales y culturales, al participar como actor en la construcción de una sociedad democrática. Se subraya en este contexto que, frente a las tecnologías incorporadas a los medios de comunicación, el ejercicio del comunicador debe comportar más inquietudes e interrogantes que respuestas.

  14. La cultura del dato

    Directory of Open Access Journals (Sweden)

    José Alberto Rodríguez

    2012-11-01

    Full Text Available Este artículo trata de la importancia que tiene la información estadística para el óptimo desempeño organizacional. Se parte del concepto de “marca” para la investigación estadística, y se da a conocer un estudio realizado en la Universidad de Costa Rica en torno a la percepción social de esta institución, a partir de su consideración como marca. Finalmente se enfatiza en la necesidad de generar una cultura del dato para obtener información y conocimiento que permitan procesos de autoevaluación e innovación, que sirvan de insumo en la consecución de los fines inherentes de la organización

  15. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available El aparecimiento del periodista digital y la educación superior en su formación, el cine indígena y la resistencia cultural, más los Grammy latinos, son temas protagónicos de este número. Se suman la prensa en el combate de piráticas corruptas, los errores de la comunicación del presidente URIBE en el referendo, el fútbol y las Relaciones Públicas en España, la libertad de prensa encarcelada, el Internet y la sociedad de la Información y México: profesiones emergentes para los comunicadores, completan la edición.

  16. Determinantes del trabajo infantil y la escolaridad: el caso del Valle del Cauca en Colombia

    Directory of Open Access Journals (Sweden)

    Sebastián Urueña Abadía

    2009-10-01

    Full Text Available Colombia, al igual que la mayoría de países latinoamericanos, consciente de las repercusiones sociales y económicas negativas del trabajo infantil, se ha comprometido en la lucha por la erradicación de este fenómeno. Prueba de ello es la ratificación por parte del gobierno colombiano en el año 2007, del Convenio 182 de la OIT sobre la Prohibición de las Peores Formas de Trabajo Infantil y la Acción Inmediata para su Eliminación. En el plano regional, como parte del Plan de Desarrollo del Departamento del Valle del Cauca 2008-2011, se está implementando actualmente una estrategia territorial de erradicación del trabajo infantil en sus 42 municipios. Considerando este panorama, este trabajo indaga cuáles son los determinantes del trabajo infantil y la escolaridad en el departamento del Valle a partir de los datos de la Encuesta Nacional de Calidad de Vida del año 2003. Para el análisis se emplea un modelo econométrico Probit Bivariado, que permite el estudio conjunto e interrelacionado de decisiones diferentes, en este caso la asistencia escolar y el trabajo.

  17. Determinantes del trabajo infantil y la escolaridad: el caso del Valle del Cauca en Colombia

    Directory of Open Access Journals (Sweden)

    Sebastián Urueña Abadía

    2009-01-01

    Full Text Available Colombia, al igual que la mayoría de países latinoamericanos, consciente de las repercusiones sociales y económicas negativas del trabajo infantil, se ha comprometido en la lucha por la erradicación de este fenómeno. Prueba de ello es la ratificación por parte del gobierno colombiano en el año 2007, del Convenio 182 de la OIT sobre la Prohibición de las Peores Formas de Trabajo Infantil y la Acción Inmediata para su Eliminación. En el plano regional, como parte del Plan de Desarrollo del Departamento del Valle del Cauca 2008-2011, se está implementando actualmente una estrategia territorial de erradicación del trabajo infantil en sus 42 municipios. Considerando este panorama, este trabajo indaga cuáles son los determinantes del trabajo infantil y la escolaridad en el departamento del Valle a partir de los datos de la Encuesta Nacional de Calidad de Vida del año 2003. Para el análisis se emplea un modelo econométrico Probit Bivariado, que permite el estudio conjunto e interrelacionado de decisiones diferentes, en este caso la asistencia escolar y el trabajo.

  18. Fundamentos del saber administrativo

    OpenAIRE

    Paola Podestá Correa; Juan Carlos Jurado Jurado

    2005-01-01

    El presente texto tiene por objetivo delimitar, de manera general, algunos de los conceptos más importantes del saber administrativo; en primera instancia, práctica administrativa y saber administrativo. Estos conceptos están ligados con los que en el texto se denominan fundamentos de la administración, estableciendo consensos sobre algunas expresiones comunes en el lenguaje administrativo, y contribuyendo a la comprensión de estos temas para los estudiantes de los primeros niv...

  19. El lenguaje del pensamiento

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    Alberto Andreu Marín

    2017-09-01

    Full Text Available ¿Somos capaces de interpretar las señales eléctricas que genera nuestro cerebro cuando estamos pensando? Lo que a priori parece ciencia ficción comienza a ser factible gracias a los avances recientes en técnicas de registro cerebral y en aprendizaje automático. Nos encontramos en el inicio de una nueva era en lo que al conocimiento del cerebro se refiere.

  20. Percepcion multisensorial del sabor

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    Charles Spence

    2010-12-01

    Full Text Available La investigación sobre la integración multisensorial de los estímulos auditivos, visuales y táctiles nos está ayudando a entender el funcionamiento de la percepción del sabor. Este conocimiento está teniendo ya un impacto sobre el diseño de alimentos y bebidas, desde los productos que compramos en un supermercado hasta aquellos que encontramos en los restaurantes con estrellas Michelin.

  1. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available Temas de fondo son: Europa entre el terror y el referéndum, ¿Libertad de prensa en los Estados Unidos? a los que suman Voceros Judiciales, el Periodismo del futuro, Crisis y Autocensura, Televisión interactiva, Violencia de género, DIRCOM, satélites de comunicación, Interacción persona-computador

  2. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Jorge Mantilla Jarrín

    2015-01-01

    Full Text Available En este número, el módulo Dibujos Animados, recoge las experiencias del primer curso realizado por el CIESPAL con apoyo de la UNICEF sobre la producción de programas educativos y culturales que utilizan este recurso como una opción comunicacional. Se trata de nuevas tecnologías aprovechadas en Cuba y que pueden ser aplicadas en nuestros países. El módulo relativo al medio ambiente habla del periodismo ecológico con importante desarrollo en América Latina, tema de actualidad que requiere preocupación por parte de los medios de comunicación. Incluye entrevistas a Gunter Grass y Jesús Polanco. Gabriel Alba adentra a los lectores en una novedosa forma de usar las computadoras. En el módulo Debate se trata la Economía, cultura y comunicación; La publicidad vía televisión, La evolución del merchandising en las novelas brasileñas ¿Exigir Ética solo al periodista?

  3. El Museo del Oro

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    Efraín Sánchez Cabra

    2003-09-01

    Full Text Available El 22 de diciembre de 1939 el Banco de la República compró un objeto de oro de 777,7 gramos de peso y 23,5 centímetros de altura que dio origen al Museo del Oro. Era un poporo quimbaya, pieza maestra de la orfebrería prehispánica. Un objeto bello bello que levanta su bruñido vientre globular y su cuello coronado por cuatro cuerpos esféricos sobre una exquisita base de filigrana fundida, y parece flotar en un espacio propio. Quien lo contempla no puede menos que asombrarse, deleitarse y sentir admiración por sus artífices. Detrás de la compra del poporo había una clara preocupación oficial por proteger una riqueza que comenzaba a entenderse como parte del patrimonio nacional. Esta motivación se pone de manifiesto en una serie de documentos relativos a su adquisición.

  4. comportamiento del consumidor

    Directory of Open Access Journals (Sweden)

    Erico Rentería Pérez

    2006-01-01

    Full Text Available En este artículo se analiza el posicionamiento exitoso de los profesionales, particularmente los jóvenes, a partir de las nuevas realidades del mundo y del mercado laboral, así como la empleabilidad como constructo, estrategias posibles y, finalmente, una discusión sobre falacias y realidades de discursos sobre mercado de trabajo profesional. La reflexión se liga a dos investigaciones, y a redes de discusión en Brasil y Colombia, que reflexionan sobre las implicaciones y requerimientos estratégicos que marcan el ingreso o permanencia en el mercado de trabajo de profesionales jóvenes, y se reconoce que esto afecta a otros tipos de profesionales. La investigación de Rentería (2006ª sobre Empleabilidad arroja información sobre las dos primeras partes. La de Enríquez y Rentería (2006 sobre Estrategias de aprendizaje y empleabilidad informa sobre la tercera. Apoyan la discusión elementos de psicología y comportamiento del consumidor. Se discute la inclusión social y calidad de vida por el trabajo.

  5. Llanto del adulto

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    Alegría Majluf

    2013-09-01

    Full Text Available Se presentan los resultados de un primer estudio transcultural del llanto del adulto que comprende 30 países, entre los que se encuentra el Perú. Vingerhoets et al. (1997 de la Universidad de Tilburg, Holanda, analizan las causas, tendencia y frecuencia del llanto, emociones y sentimientos que inducen al llanto, diferencias y similitudes entre los países y los sexos. Los autores encuentran que las mujeres tienden a llorar con más frecuencia e intensidad que los varones, advirtiendo que en algunos países las mujeres establecen mayor relación entre la tendencia al llanto y el ciclo menstrual que en otros. The results of a first cross-cultural study on adult crying in 30 countries including Peru are presented. Vingerhoets et al. (1997 from the University of Tilburg have analyzed motives, tendencies and frequency of crying, emotions and feelings that provoke crying, as well as differences and similarities among countries and sexes. Results show that women have a tendency to cry more frequently and intensively than men. It has also been noted that, in certain countries, there is a link between crying in women and their monthly period.

  6. Carta del Editor

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    Jorge Aguirre

    2015-01-01

    Full Text Available La crisis de la prensa Argentina a efecto del mal manejo de la economía y las finanzas, ocupa el tema central. Pasa revista a tres temas de actualidad: El aumento de cobertura y difusión de la prensa gratuita; los esfuerzos de los "viejos" diarios por cambiar de apariencia y el caso del diario estadounidense TODAY que hace veinte años dio un cambio revolucionario en la forma de hacer periodismo diario. Se analizan también temas como: el "carisma" de los líderes actuales, los acuerdos entre los medios de comunicación y el gobierno de México para la difusión de planes y programas oficiales y el rol de los medios en el proceso de establecimiento del ALCA. Agrega el tema controversial sobre la Ley de radiodifusión privada, vigente desde la época de la dictadura pinochetista. En este mismo campo de la Radio otro artículo señala las normas para "contar las noticias" con impacto e interés.

  7. Carta del Editor

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    Luis Eladio Proaño

    2015-01-01

    Full Text Available Artículo de fondo es un ejemplo de una campaña exitosa de Relaciones Públicas realizada para rescatar a Medellín para el turismo, ahora herida de muerte por el narcotráfico. Reinicia el tema sobre el cine, recordando el aniversario del nacimiento de Luis Buñuel. Y sobre el Nuevo Orden Internacional de la Información, Luis Ramiro Beltrán da respuesta a las múltiples interrogantes planteadas en la controversia surgida alrededor del tema. Se da a conocer cómo era el periódico de ayer, de hoy y del futuro frente al desafío de las nuevas tecnologías. Se señala el camino para hacer publicidad en Internet. El Internet y la radio nuevos actores para un mismo mercado. Y para los interesados en la investigación se trata cómo y cuándo hacer sondeos flash y se cierra con el lenguaje periodístico cuándo el dequeísmo es lícito.

  8. [Feminismos del siglo XXI

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    Yaratullah Monturiol

    2013-07-01

    Full Text Available Yaratullah Monturiol propone un diálogo basado en la acción, en la lucha de las mujeres musulmana que paso a paso llegará a transformar la realidad. Define el feminismo musulmán como plural y expone la necesidad del conocimiento de las fuentes textuales para su desarrollo y construcción identitaria. También expone los obstáculos que se han encontrado para avanzar, como la instrumentalización de la causa femenina por parte de los hombres, convirtiéndola en una plataforma personal y desvalorizándola como si fuera objeto de propaganda. Además, el posible temor de la disolución dl patriarcado ha provocado el rechazo el feminismo, y la división del mismo. Así, Monturiol presenta un feminismo islámico que lucha para cambiar, desde dentro, la forma de ver y de percibir de los musulmanes y del islam.

  9. Fractura del ahorcado

    Directory of Open Access Journals (Sweden)

    Esteban Roig Fabré

    2003-03-01

    Full Text Available Con el nombre de "fractura del ahorcado" se conocen 2 tipos de lesiones del axis de igual apariencia radiológica, de las cuales la más frecuente es la espondilolistesis traumática del axis. Estas lesiones son afecciones relativamente infrecuentes, que crean problemas de manejo a ortopédicos y neurocirujanos por su comportamiento biomecánico particular. Se hace una revisión de la clasificación y fisiopatología de la lesión, y se describen los métodos actuales de diagnóstico por imagen y de tratamiento de ésta, donde se hace énfasis en las técnicas de atornillado transpedicularThere are 2 types of axis injuries with the same radiological appearance that are known as Hangman´s fracture. The most frequent is the traumatic spondylolisthesis. These injuries are relatively uncommon and create management problems for orthopedists and neurosurgeons due to their particular biomechanical behavior. A review of the classification and physiopathology of the injury is made and the current diagnostic imaging methods and treatment are described. Emphasis is made on the transpedicular clamping

  10. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available Abre la revista una retrospectiva de la crisis económica, política y social en la que se precipitó Argentina (2001-2002 y el tratamiento que dieron los medios a esta situación. En opinión se describe el significado de los nuevos paradigmas de Internet como: interactividad, personalidad, multimedialidad, hipertextualidad, actualización, abundancia y mediación. Responde a la cuestión de ¿cómo y cuándo en la prensa latinoamericana sigue imperando la prensa amarilla? Recoge en un artículo los factores que más inciden en el éxito o fracaso de una campaña política. Aborda la implantación de una nueva moneda única en la Unión Europea y sus incidencias. Destaca las consecuencias vividas por México tras el ataque terrorista del 11 de septiembre 2001 y analiza el tratamiento que los medios dan a las informaciones procedentes del Tercer Mundo en Europa. Contesta a la pregunta inquietante sobre las posibilidades del liberalismo económico para garantizar o contrarrestar la libertad de prensa y por último se aclara los mitos y realidades que se han tejido alrededor de Windows XP de Microsoft.

  11. Los gestos del hechizo

    Directory of Open Access Journals (Sweden)

    Aluizio Trinta

    2015-01-01

    Full Text Available Inicia el texto con una explicación amplia de lo que se entiende por la telenovela. El interés de la semiótica por la telenovela es reciente. La telenovela es un mecanismo significante, siempre capaz de generar múltiples significados. ¿Es posible aplicar el análisis semiótico a la comunicación no verbal, es decir, la gestualidad, la postura y la disposición espacial que asumen los cuerpos de los inter-agentes, para ampliar la comprensión del género? Señala que los músculos de la cara son muy versátiles. Las expresiones faciales son un indicio fidedigno de la ira, el temor, la vergüenza, el asombro, el disgusto, la tristeza, la alegría, el placer, el dolor. El aspecto del rostro irradia siempre un mensaje que el maquillaje intenta ocultar o resaltar. Refiere los signos del silencio y de la apariencia, el cuerpo y la personalidad, el repertorio gestual de los personajes.

  12. Charge Breeding of Radioactive Ions

    CERN Document Server

    Wenander, F J C

    2013-01-01

    Charge breeding is a technique to increase the charge state of ions, in many cases radioactive ions. The singly charged radioactive ions, produced in an isotope separator on-line facility, and extracted with a low kinetic energy of some tens of keV, are injected into a charge breeder, where the charge state is increased to Q. The transformed ions are either directed towards a dedicated experiment requiring highly charged ions, or post-accelerated to higher beam energies. In this paper the physics processes involved in the production of highly charged ions will be introduced, and the injection and extraction beam parameters of the charge breeder defined. A description of the three main charge-breeding methods is given, namely: electron stripping in gas jet or foil; external ion injection into an electron-beam ion source/trap (EBIS/T); and external ion injection into an electron cyclotron resonance ion source (ECRIS). In addition, some preparatory devices for charge breeding and practical beam delivery aspects ...

  13. Cobalt alloy ion sources for focused ion beam implantation

    Energy Technology Data Exchange (ETDEWEB)

    Muehle, R.; Doebeli, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Zimmermann, P. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Cobalt alloy ion sources have been developed for silicide formation by focused ion beam implantation. Four eutectic alloys AuCo, CoGe, CoY and AuCoGe were produced by electron beam welding. The AuCo liquid alloy ion source was investigated in detail. We have measured the emission current stability, the current-voltage characteristics, and the mass spectrum as a function of the mission current. (author) 1 fig., 2 refs.

  14. Positive ion irradiation facility

    International Nuclear Information System (INIS)

    Braby, L.A.

    1985-01-01

    Many questions about the mechanisms of the response of cells to ionizing radiation can best be investigated using monoenergetic heavy charged particle beams. Questions of the role of different types of damage in the LET effect, for example, are being answered by comparing repair kinetics for damage induced by electrons with that produced by helium ions. However, as the models become more sophicated, the differences between models can be detected only with more precise measurements, or by combining high- and low-LET irradiations in split-dose experiments. The design of the authors present cell irradiation beam line has limited the authors to irradiating cells in a partial vacuum. A new way to mount the dishes and bring the beam to the cells was required. Several means of irradiating cells in mylar-bottom dishes have been used at other laboratories. For example at the RARAF Facility, the dual ion experiments are done with the dish bottom serving as the beam exit window but the cells are in a partial vacuum to prevent breaking the window. These researchers have chosen instead to use the dish bottom as the beam window and to irradiate the entire dish in a single exposure. A special, very fast pumping system will be installed at the end of the beam line. This system will make it possible to irradiate cells within two minutes of installing them in the irradiation chamber. In this way, the interaction of electron and ion-induced damage in Chlamydomonas can be studied with time between doses as short as 5 minutes

  15. Contact ionization ion source

    International Nuclear Information System (INIS)

    Hashmi, N.; Van Der Houven Van Oordt, A.J.

    1975-01-01

    An ion source in which an apertured or foraminous electrode having a multiplicity of openings is spaced from one or more active surfaces of an ionisation electrode, the active surfaces comprising a material capable of ionising by contact ionization a substance to be ionized supplied during operation to the active surface or surfaces comprises means for producing during operation a magnetic field which enables a stable plasma to be formed in the space between the active surface or surfaces and the apertured electrode, the field strength of the magnetic field being preferably in the range between 2 and 8 kilogauss. (U.S.)

  16. Nanostructuring by ion beam

    International Nuclear Information System (INIS)

    Valbusa, U.; Boragno, C.; Buatier de Mongeot, F.

    2003-01-01

    In metals, the surface curvature dependence of the sputtering yield and the presence of an extra energy barrier whenever diffusing adatoms try to descend step edges, produce a similar surface instability, which builds up regular patterns. By tuning the competition between these two mechanisms, it is possible to create self-organized structures of the size of few nanometers. Height, lateral distance and order of the structures change with the deposition parameters like ion energy, dose, incident angle and substrate temperature. The paper offers an overview of the experiments carried out and foresees possible applications of these results in the area of material science

  17. Ion implantation for semiconductors

    International Nuclear Information System (INIS)

    Grey-Morgan, T.

    1995-01-01

    Full text: Over the past two decades, thousands of particle accelerators have been used to implant foreign atoms like boron, phosphorus and arsenic into silicon crystal wafers to produce special embedded layers for manufacturing semiconductor devices. Depending on the device required, the atomic species, the depth of implant and doping levels are the main parameters for the implantation process; the selection and parameter control is totally automated. The depth of the implant, usually less than 1 micron, is determined by the ion energy, which can be varied between 2 and 600 keV. The ion beam is extracted from a Freeman or Bernas type ion source and accelerated to 60 keV before mass analysis. For higher beam energies postacceleration is applied up to 200 keV and even higher energies can be achieved by mass selecting multiplycharged ions, but with a corresponding reduction in beam output. Depending on the device to be manufactured, doping levels can range from 10 10 to 10 15 atoms/cm 2 and are controlled by implanter beam currents in the range up to 30mA; continuous process monitoring ensures uniformity across the wafer of better than 1 % . As semiconductor devices get smaller, additional sophistication is required in the design of the implanter. The silicon wafers charge electrically during implantation and this charge must be dissipated continuously to reduce the electrical stress in the device and avoid destructive electrical breakdown. Electron flood guns produce low energy electrons (below 10 electronvolts) to neutralize positive charge buildup and implanter design must ensure minimum contamination by other isotopic species and ensure low internal sputter rates. The pace of technology in the semiconductor industry is such that implanters are being built now for 256 Megabit circuits but which are only likely to be widely available five years from now. Several specialist companies manufacture implanter systems, each costing around US$5 million, depending on the

  18. Heavy ion beams from the new Hungarian ECR ion source

    International Nuclear Information System (INIS)

    Biri, S.; Valek, A.; Ditroi, F.; Koivisto, H.; Arje, J.; Stiebing, K.; Schmidt, L.

    1998-01-01

    The first beams of highly charged ions in Hungary were obtained in fall of 1996. The new 14.5 GHz ECR ion source of ATOMKI produced beams of multiply charged ions with remarkable intensities at first experiments. Since then, numerous further developments were carried out. An external electrondonor electrode drastically increased the plasma density and, consequently, the intensity of highly charged ions. These upgrades concentrated mainly on beams from gaseous elements and were carried out by the ECRIS team of ATOMKI. Another series of experiments - ionising from solids - however, was done in the framework of an international collaboration. The first metal ion beam has been extracted from the ECRIS in November 1997 using the known method of Metal Ions from Volatile Compounds (MIVOC). The possibility to put the MIVOC chamber inside the ion source was also tested and the dosing regulation problem of metal vapours inside the ion source was solved. As a result, beams of more than 10 μA of highly charged Fe and Ni ions were produced. (author)

  19. Sympathetic cooling of ions in a hybrid atom ion trap

    Energy Technology Data Exchange (ETDEWEB)

    Hoeltkemeier, Bastian

    2016-10-27

    In this thesis the dynamics of a trapped ion immersed in a spatially localized buffer gas is investigated. For a homogeneous buffer gas, the ion's energy distribution reaches a stable equilibrium only if the mass of the buffer gas atoms is below a critical value. This limitation can be overcome by using multipole traps in combination and/or a spatially confined buffer gas. Using a generalized model for elastic collisions of the ion with the buffer gas atoms, the ion's energy distribution is numerically determined for arbitrary buffer gas distributions and trap parameters. Three regimes characterized by the respective analytic form of the ion's equilibrium energy distribution are found. One of these is a novel regime at large atom-to-ion mass ratios where the final ion temperature can tuned by adiabatically decreasing the spatial extension of the buffer gas and the effective ion trap depth (forced sympathetic cooling). The second part of the thesis presents a hybrid atom ion trap designed for sympathetic cooling of hydroxide anions. In this hybrid trap the anions are immersed in a cloud of laser cooled rubidium atoms. The translational and rovibrational temperatures of the anions is probed by photodetachment tomography and spectroscopy which shows the first ever indication of sympathetic cooling of anions by laser cooled atoms.

  20. Production of negative hydrogen ions from accelerated cluster ions

    International Nuclear Information System (INIS)

    Becker, E.W.; Falter, H.D.; Hagena, O.F.; Henkes, W.; Klingelhoefer, R.; Moser, H.O.; Obert, W.; Poth, I.

    1976-11-01

    Cluster ion acceleration is a method particularly well suited to produce neutral beams of high particle current density at energies of the order of 1 keV/atom. Since this is the energy required for converting hydrogen atoms or molecules into negative ions in a cesium vapour cell, it is proposed to use cluster ions for the production of negative ion beams of high current density. The system is envisaged as a tandem accelerator with a terminal voltage of 1 MV. (orig.) [de

  1. A novel planar ion funnel design for miniature ion optics

    International Nuclear Information System (INIS)

    Chaudhary, A.; Amerom, Friso H. W. van; Short, R. T.

    2014-01-01

    The novel planar ion funnel (PIF) design presented in this article emphasizes simple fabrication, assembly, and operation, making it amenable to extreme miniaturization. Simulations performed in SIMION 8.0 indicate that ion focusing can be achieved by using a gradient of electrostatic potentials on concentric metal rings in a plane. A prototype was fabricated on a 35 × 35 mm custom-designed printed circuit board (PCB) with a center hole for ions to pass through and a series of concentric circular metal rings of increasing diameter on the front side of the PCB. Metal vias on the PCB electrically connected each metal ring to a resistive potential divider that was soldered on the back of the PCB. The PIF was tested at 5.5 × 10 −6 Torr in a vacuum test setup that was equipped with a broad-beam ion source on the front and a micro channel plate (MCP) ion detector on the back of the PIF. The ion current recorded on the MCP anode during testing indicated a 23× increase in the ion transmission through the PIF when electric potentials were applied to the rings. These preliminary results demonstrate the functionality of a 2D ion funnel design with a much smaller footprint and simpler driving electronics than conventional 3D ion funnels. Future directions to improve the design and a possible micromachining approach to fabrication are discussed in the conclusions

  2. Note: Ion source design for ion trap systems

    Science.gov (United States)

    Noriega, J. R.; Quevedo, M.; Gnade, B.; Vasselli, J.

    2013-06-01

    A small plasma (glow discharge) based ion source and circuit are described in this work. The ion source works by producing a high voltage pulsed discharge between two electrodes in a pressure range of 50-100 mTorr. A third mesh electrode is used for ion extraction. The electrodes are small stainless steel screws mounted in a MACOR ionization chamber in a linear arrangement. The electrode arrangement is driven by a circuit, design for low power operation. This design is a proof of concept intended for applications on small cylindrical ion traps.

  3. Practical aspects of trapped ion mass spectrometry, 5 applications of ion trapping devices

    CERN Document Server

    March, Raymond E

    2009-01-01

    Examines ion/neutral and ion/ion reactions, ion spectroscopy, and the structural characterization of proteins and peptides using quadropole ion trap mass spectrometry, Fourier transform - ion cyclotron resonance (FT-ICR) mass spectrometry, and traveling wave ion mobility mass spectrometry.

  4. Nuevos usos del cemento

    Directory of Open Access Journals (Sweden)

    Páez Balaca, A.

    1977-04-01

    Full Text Available In this article, the evolution of the different systems of transporting and storing submarine oil and its by-products (petroleum gas and natural gas, is dealt with stressing the importance of the use of concrete boats. Due to the high cost of oil pipelines, we have passed from tanks built on land to prestressed concrete tanks which can be berthed at great depths or anchored to the bottom to keep them afloat, it being possible to unmoor them for transferring them. Transporting and storing liquated gas leads US to see the advantages of prestressed concrete over steel, as the latter becomes brittle at low temperatures, whereas the former's strength increases. The different forms and possible sections are analyzed, stressing the great importance of the solution of the double concrete hull with pearlite insulation. Finally, a study is made of «light concretes », not the classical types used as thermal and acoustic insulation, but the semi-heavy ones made with expanded clay, high quality sand and P-450 cement, which technique is not yet as developed in Spain at might be wished.En este artículo se trata la evolución de los distintos sistemas de transporte y almacenamiento del petróleo submarino y sus derivados (gas de petróleo y gas natural, resaltando la importancia del uso de barcos de hormigón. Debido al gran coste de los oleoductos, se ha pasado de los tanques construidos en tierra firme a los depósitos de hormigón pretensado que pueden estar fondeados a gran profundidad o anclados al fondo para mantenerlos flotantes, existiendo la posibilidad de poder desamarrarlos para su traslado. El transporte y almacenamiento del gas licuado nos hace ver las ventajas del hormigón pretensado sobre el acero, pues éste se vuelve quebradizo a bajas temperaturas, mientras aquél aumenta su resistencia. Se analizan las diferentes formas y secciones posibles, destacando la gran importancia de la solución del doble casco de hormigón con

  5. Competitividad sectorial internacional. Caso: sector del cuero y del calzado

    Directory of Open Access Journals (Sweden)

    Diana Carolina Villegas Álvarez

    2007-01-01

    Full Text Available El presente escrito se origina en un trabajo de investigación cuya pretensión fue indagar sobre el nivel de competitividad internacional (C.I, del sector del cuero y del calzado colombiano, mediante la aplicación de indicadores que, a partir de la información estadística de las variables de comercio exterior permiten establecer ciertas relaciones que dan cuenta de la importancia del producto en los mercados de los países de la Comunidad Andina de Naciones (CAN, seleccionados para la comparación.

  6. Riesgos laborales en trabajadores del sector informal del Cauca, Colombia

    OpenAIRE

    Augusto Muñoz Caicedo; Pilar Mirely Chois Lenis

    2014-01-01

    Objetivo: describir los riesgos laborales de las personas ocupadas en el sector informal del comercio, en cinco municipios del departamento del Cauca, durante el año 2011. Métodos: estudio descriptivo, transversal, desarrollado con 223 sujetos a quienes se les aplicó una encuesta estandarizada a nivel nacional. Resultados: más del 20% de los taxistas y lecheros están expuestos a riesgos de seguridad, mientras que aproximadamente 1 de cada 4 de los vendedores ambulantes, carretilleros y vended...

  7. Max Weber o el enigma emocional del origen del capitalismo

    OpenAIRE

    EDUARDO BERICAT ALASTUEY

    2001-01-01

    Se analiza el trabajo clave de Max Weber, La ética protestante y el espíritu del capitalismo, desde la perspectiva de la Sociología de las Emociones. Aunque la inclusión de las emociones de los fenómenos sociales es clave para entender la idea de Weber sobre el dogma de la predestinación, los sociólogos han trivializado el papel de la emoción. Tras detallar la creencia de Weber en que el espíritu del capitalismo parte del conocimiento de que el destino del hombre está predeterminado (la ética...

  8. Proton and carbon ion therapy

    CERN Document Server

    Lomax, Tony

    2013-01-01

    Proton and Carbon Ion Therapy is an up-to-date guide to using proton and carbon ion therapy in modern cancer treatment. The book covers the physics and radiobiology basics of proton and ion beams, dosimetry methods and radiation measurements, and treatment delivery systems. It gives practical guidance on patient setup, target localization, and treatment planning for clinical proton and carbon ion therapy. The text also offers detailed reports on the treatment of pediatric cancers, lymphomas, and various other cancers. After an overview, the book focuses on the fundamental aspects of proton and carbon ion therapy equipment, including accelerators, gantries, and delivery systems. It then discusses dosimetry, biology, imaging, and treatment planning basics and provides clinical guidelines on the use of proton and carbon ion therapy for the treatment of specific cancers. Suitable for anyone involved with medical physics and radiation therapy, this book offers a balanced and critical assessment of state-of-the-art...

  9. Air ions and aerosol science

    International Nuclear Information System (INIS)

    Tammet, H.

    1996-01-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4 endash 1.8 nm. copyright 1996 American Institute of Physics

  10. Ion climate and radon concentration

    International Nuclear Information System (INIS)

    Busbarna, L.

    1981-01-01

    Characteristic values of radon concentration in natural ion climate and in open air were compared and the effect of artificially produced negative ion excess on the radon concentration of air was studied. The results show that the radon concentration measurable at the rise of negative ion excess is smaller than that in the case of natural equilibrium. This effect can be utilized lowering the background of the scintillation chambers, thus increasing their sensitivity. The negative ions of the artificial ion climate lower radon concentration in closed space. The question arises whether only the ion climate is responsible for the effects on the organism and on the nervous system or the radon concentration of the air also contributes to them. (author)

  11. Ion implantation: an annotated bibliography

    International Nuclear Information System (INIS)

    Ting, R.N.; Subramanyam, K.

    1975-10-01

    Ion implantation is a technique for introducing controlled amounts of dopants into target substrates, and has been successfully used for the manufacture of silicon semiconductor devices. Ion implantation is superior to other methods of doping such as thermal diffusion and epitaxy, in view of its advantages such as high degree of control, flexibility, and amenability to automation. This annotated bibliography of 416 references consists of journal articles, books, and conference papers in English and foreign languages published during 1973-74, on all aspects of ion implantation including range distribution and concentration profile, channeling, radiation damage and annealing, compound semiconductors, structural and electrical characterization, applications, equipment and ion sources. Earlier bibliographies on ion implantation, and national and international conferences in which papers on ion implantation were presented have also been listed separately

  12. Fundamental processes in ion plating

    International Nuclear Information System (INIS)

    Mattox, D.M.

    1980-01-01

    Ion plating is a generic term applied to film deposition processes in which the substrate surface and/or the depositing film is subjected to a flux of high energy particles sufficient to cause changes in the interfacial region of film properties compared to a nonbombarded deposition. Ion plating is being accepted as an alternative coating technique to sputter deposition, vacuum evaporation and electroplating. In order to intelligently choose between the various deposition techniques, the fundamental mechanisms, relating to ion plating, must be understood. This paper reviews the effects of low energy ion bombardment on surfaces, interface formation and film development as they apply to ion plating and the implementation and applications of the ion plating process

  13. Rectangular ion funnel: a new ion funnel interface for structures for lossless ion manipulations.

    Science.gov (United States)

    Chen, Tsung-Chi; Webb, Ian K; Prost, Spencer A; Harrer, Marques B; Norheim, Randolph V; Tang, Keqi; Ibrahim, Yehia M; Smith, Richard D

    2015-01-06

    Structures for lossless ion manipulations (SLIM) have recently demonstrated the ability for near lossless ion focusing, transfer, and trapping in subatmospheric pressure regions. While lossless ion manipulations are advantageously applied to the applications of ion mobility separations and gas phase reactions, ion introduction through ring electrode ion funnels or more conventional ion optics to SLIM can involve discontinuities in electric fields or other perturbations that result in ion losses. In this work, we developed and investigated a new funnel design that aims to seamlessly couple to SLIM at the funnel exit. This rectangular ion funnel (RIF) was initially evaluated by ion simulations, fabricated utilizing printed circuit board technology, and tested experimentally. The RIF was integrated to a SLIM-time of flight (TOF) MS system, and the operating parameters, including RF, DC bias of the RIF electrodes, and electric fields for effectively interfacing with a SLIM, were characterized. The RIF provided a 2-fold sensitivity increase without significant discrimination over a wide m/z range and well matched to that of SLIM, along with greatly improved SLIM operational stability.

  14. Tandem Terminal Ion Source

    International Nuclear Information System (INIS)

    None

    2000-01-01

    OAK-B135 Tandem Terminal Ion Source. The terminal ion source (TIS) was used in several experiments during this reporting period, all for the(sup 7)Be((gamma))(sup 8)B experiment. Most of the runs used(sup 1)H(sup+) at terminal voltages from 0.3 MV to 1.5 MV. One of the runs used(sup 2)H(sup+) at terminal voltage of 1.4 MV. The other run used(sup 4)He(sup+) at a terminal voltage of 1.37 MV. The list of experiments run with the TIS to date is given in table 1 below. The tank was opened four times for unscheduled source repairs. On one occasion the tank was opened to replace the einzel lens power supply which had failed. The 10 kV unit was replaced with a 15 kV unit. The second time the tank was opened to repair the extractor supply which was damaged by a tank spark. On the next occasion the tank was opened to replace a source canal which had sputtered away. Finally, the tank was opened to replace the discharge bottle which had been coated with aluminum sputtered from the exit canal

  15. SUERC AMS ion detection

    Science.gov (United States)

    Maden, C.; Anastasi, P. A. F.; Dougans, A.; Freeman, S. P. H. T.; Kitchen, R.; Klody, G.; Schnabel, C.; Sundquist, M.; Vanner, K.; Xu, S.

    2007-06-01

    In a short time Be, C, Al, Cl, Ca and I accelerator mass spectrometry (AMS) have been established on the National Electrostatics Corporation (NEC) 5 MV pelletron system at the Scottish Universities Environmental Research Centre (SUERC). While summarising the present performance of the system, this report will focus on the details of ion detection, which sample materials are used and the analytical procedures employed for each individual species during routine analysis. All rare isotope detection is with a single flexible detector and ion event analysis system, but switching of analysed species typically requires a detector reconfiguration. Configurations for routine 10Be, 14C, 26Al, 36Cl, 41Ca and 129I detection have been established and will be presented here. Notably, there has proven to be sufficient suppression of the isobaric interferences of 36Cl and 41Ca in the 5+ charge state using an argon gas stripper at a terminal voltage of 5.0 MV to allow for routine analysis of these isotopes.

  16. First operations of the LNS heavy ions facility

    International Nuclear Information System (INIS)

    Calabretta, L.; Ciavola, G.; Cuttone, G.; Gammino, S.; Gmaj, P.; Migneco, E.; Raia, G.; Rifuggiato, D.; Rovelli, A.; Sura, J.; Scuderi, V.; Acerbi, E.; Alessandria, F.; Bellomo, G.; Bosotti, A.; Martinis, C. de; Giove, D.; Michelato, P.; Pagani, C.; Rossi, L.

    1996-01-01

    A heavy ion facility is now available at laboratorio nazionale del Sud (LNS) of Catania. It can deliver beams with an energy up to 100 MeV/amu. The facility is based on a 15 MV HVEC tandem and a K=800 superconducting cyclotron as booster. During the last year, the facility came into operation. A 58 Ni beam delivered by the tandem has been radially injected in the SC and then has been accelerated and extracted at 30 MeV/amu. In this paper the status of the facility together with the experience gained during the commissioning will be extensively reported. (orig.)

  17. Binding energy of protonium ions

    Science.gov (United States)

    Assad Abdel-Raouf, Mohamed

    2009-11-01

    The goal of the present work is to calculate the binding energy of the protonium ions bar PPe+ and bar PPe- using Rayleigh- Ritz variational method. It is indicated that an employment of 21 components of the trial wavefunction yields -0.08793 eV as the ground state energy of these ions. Our result agrees quite well with recently obtained results based on elaborate Monte Carlo approximations. It confirms the possible formation of these ions in laboratory.

  18. Highly Stripped Ion Sources for MeV Ion Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, Ady

    2009-06-30

    Original technical objectives of CRADA number PVI C-03-09 between BNL and Poole Ventura, Inc. (PVI) were to develop an intense, high charge state, ion source for MeV ion implanters. Present day high-energy ion implanters utilize low charge state (usually single charge) ion sources in combination with rf accelerators. Usually, a MV LINAC is used for acceleration of a few rnA. It is desirable to have instead an intense, high charge state ion source on a relatively low energy platform (de acceleration) to generate high-energy ion beams for implantation. This de acceleration of ions will be far more efficient (in energy utilization). The resultant implanter will be smaller in size. It will generate higher quality ion beams (with lower emittance) for fabrication of superior semiconductor products. In addition to energy and cost savings, the implanter will operate at a lower level of health risks associated with ion implantation. An additional aim of the project was to producing a product that can lead to long­ term job creation in Russia and/or in the US. R&D was conducted in two Russian Centers (one in Tomsk and Seversk, the other in Moscow) under the guidance ofPVI personnel and the BNL PI. Multiple approaches were pursued, developed, and tested at various locations with the best candidate for commercialization delivered and tested at on an implanter at the PVI client Axcelis. Technical developments were exciting: record output currents of high charge state phosphorus and antimony were achieved; a Calutron-Bemas ion source with a 70% output of boron ion current (compared to 25% in present state-of-the-art). Record steady state output currents of higher charge state phosphorous and antimony and P ions: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb {sup 4 +}, Sb{sup 5+}, and Sb{sup 6+} respectively. Ultimate commercialization goals did not succeed (even though a number of the products like high

  19. Efectos colaterales del voto preferente

    Directory of Open Access Journals (Sweden)

    Luis Diego Brenes Villalobos

    2012-07-01

    Full Text Available El artículo describe la multiplicidad de potenciales efectos que la implementación del voto preferente podría acarrear en el ordenamiento jurídico y el sistema de partidos. La primera parte del análisis se dirige a caracterizar y definir el voto preferencial. En segunda instancia, el estudio comprenderá la revista de los efectos colaterales del voto preferente como modalidad de votación.

  20. Negative ions of polyatomic molecules

    International Nuclear Information System (INIS)

    Christophorou, LG.

    1980-01-01

    In this paper general concepts relating to, and recent advances in, the study of negative ions of polyatomic molecules are discussed with emphasis on halocarbons. The topics dealt with in the paper are as follows: basic electron attachment processes, modes of electron capture by molecules, short-lived transient negative ions, dissociative electron attachment to ground-state molecules and to hot molecules (effects of temperature on electron attachment), parent negative ions, effect of density, nature, and state of the medium on electron attachment, electron attachment to electronically excited molecules, the binding of attached electrons to molecules (electron affinity), and the basic and the applied significance of negative-ion studies

  1. Ion injector for electrostatic accelerator

    International Nuclear Information System (INIS)

    Novikov, M.T.; Tsygikalo, A.A.

    1980-01-01

    Basing on the analysis of formulae connecting beam parameters at the input and output of an electrostatic accelerator, a design of an ion injector for a charge-exchange accelerator is suggested. The distinguishing injector feature is that it contains a preaccelerator with autofocusing of the beam at its output, which provides better matching of ion source and accelerator operating conditions when preserving the conditions of beam autofocusing in the accelerator. Such an injector is a self-contained instrument. It allows control, within certain limits, of ion optics of inlet lenses of the accelerator and preaccelerator during operation when preserving better matching of ion source operation with the accelerator [ru

  2. Ion beam assisted film growth

    CERN Document Server

    Itoh, T

    2012-01-01

    This volume provides up to date information on the experimental, theoretical and technological aspects of film growth assisted by ion beams.Ion beam assisted film growth is one of the most effective techniques in aiding the growth of high-quality thin solid films in a controlled way. Moreover, ion beams play a dominant role in the reduction of the growth temperature of thin films of high melting point materials. In this way, ion beams make a considerable and complex contribution to film growth. The volume will be essential reading for scientists, engineers and students working in thi

  3. El retraso del lenguaje primario :

    OpenAIRE

    Sampol Perelló, Catalina

    2014-01-01

    Se realizara un estudio sobre el concepto de retraso del lenguaje. Se ve la aplicación del modelo de evaluación a un alumno concreto, analizando todas las sesiones. La evaluación es el punto de partida para establecer el diagnóstico del trastorno del lenguaje e iniciar el proceso de tratamiento y la rehabilitación. Se finaliza con el informe logopédico, tipificando el problema y estableciendo las recomendaciones generales o específicas necesarias

  4. Los aspectos procesales del concurso

    OpenAIRE

    Vegas Torres, Jaime

    2004-01-01

    Tribunal competente. A) Los Juzgados de lo Mercantil y la especialización. B) Extensión de la jurisdicción del juez del concurso. C) Competencia territorial. La declaración del concurso. Los efectos procesales de la declaración de concurso. Actuaciones judiciales relacionadas con la determinación de las masas activa y pasiva del concurso. A) Actuaciones judiciales relacionadas con la formación de la masa activa. B) Actuaciones judiciales relacionadas con la formación de la masa pasiva. Resolu...

  5. Vida y muerte del ozono.

    OpenAIRE

    Duque Parra, Jorge Eduardo

    2018-01-01

    Nuestro planeta tierra, el tercer planeta del sistema solar, debería llamarse el planeta gas, pues presenta una  capa gaseosa variada que le hace particular y de mayor volumen que el del débil cascarón lítico de 50 km que nos separa del manto y del núcleo terrestre, haciendo de la tierra un horno interior con temperaturas calculadas de hasta 4000 grados centígrados. La radiación solar llega como onda electromagnética, pero gran parte es reflejada y hace que nuestro planeta brille con un albed...

  6. El pie del adulto mayor

    OpenAIRE

    Parodi García, José Francisco

    2005-01-01

    Acta Médica Peruana es una publicación del Colegio Médico del Perú El estudio del pie y sus patologías es un capítulo muy importante de la Geriatría. Las patologías del pie no escapan las características comunes de muchos síndromes geriátricos como son el ser asumidos como "normales para la edad", ser poco valorados, menospreciados, no tratados, con gran impacto sobre la salud en general y la calidad de vida.

  7. El Gobierno del mal menor

    DEFF Research Database (Denmark)

    Agustin, Oscar Garcia

    2012-01-01

    El Gobierno no aspira a ser bueno ni malo. Se conforma con ser el Gobierno del mal menor, cuyas medidas drásticas y poco populares están destinadas a salvar a los ciudadanos del desastre que no ha llegado todavía pero podría llegar.......El Gobierno no aspira a ser bueno ni malo. Se conforma con ser el Gobierno del mal menor, cuyas medidas drásticas y poco populares están destinadas a salvar a los ciudadanos del desastre que no ha llegado todavía pero podría llegar....

  8. LIDERAZGO VISIONARIO: CENTRO DEL CONOCIMIENTO

    Directory of Open Access Journals (Sweden)

    Rafael Pérez Uribe

    2013-07-01

    Full Text Available El gestor del conocimiento es el ser humano. En el mundo como en las empresas es el centro de la destrucción y la creación del conocimiento. Por esta razón en las empresas se deben generar los escenarios adecuados para revertir el conocimiento de las personas y convertirlo en patrimonio de las organizaciones. El papel del líder es vital para la construcción de escenarios adecuados para que los trabajadores se conviertan en auténticos gestores del «knowledge» y esto permita que las organizaciones sean entes permanentes de aprendizaje continuo.

  9. Analisi del decadimento $W -> \\tau \

    CERN Document Server

    Coscetti, Simone

    Questo lavoro di tesi si e' svolto nell'ambito dell'esperimento CMS a LHC, ed in particolare verte sullo studio delle strategie di identificazione off-line del leptone tau, atteso tra i prodotti di decadimento del bosone di Higgs, cosi' come di altre particelle previste in altri modelli teorici. Il canale utilizzato per testare la procedura di identificazione del tau e' il decadimento semileptonico del bosone vettore W. Infine, sulla base dei risultati ottenuti viene presentata una stima quantitativa della sezione d'urto di produzione pp-> W + X

  10. Ion-Bombardment of X-Ray Multilayer Coatings - Comparison of Ion Etching and Ion Assisted Deposition

    NARCIS (Netherlands)

    Puik, E. J.; van der Wiel, M. J.; Zeijlemaker, H.; Verhoeven, J.

    1991-01-01

    The effects of two forms of ion bombardment treatment on the reflectivity of multilayer X-ray coatings were compared: ion etching of the metal layers, taking place after deposition, and ion bombardment during deposition, the so-called ion assisted deposition. The ion beam was an Ar+ beam of 200 eV,

  11. Determination of hydrolysis constants for gadolinium in ion strength media 2M of NaCl, NaClO{sub 4} and KCl at 303 K; Determinacion de las constanted de hidrolisis del gadolinio en los medios de fuerza ionica 2M de NaCl, NaClO{sub 4} y KCl, a 303 K

    Energy Technology Data Exchange (ETDEWEB)

    Serna M, S.; Jimenez R, M.; Solache R, M. [Instituto Nacional de Investigaciones Nucleares, Departamento de Quimica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    This work was made with the purpose to extend information about the hydrolysis constants of gadolinium (III) in ion strength media 2M of NaCl, NaClO{sub 4}, KCl at 303 K using the potentiometric method for this determination, and analysing starting from those data, the influence of anions and cations. It is concluded that the media which were determined the hydrolysis constants are very important and it is recommended the sodium perchlorate as the more adequate salt for those determinations. Also it was obtained the distribution diagrams of chemical species in each one of the media studied. (Author)

  12. Salt stress induced ion accumulation, ion homeostasis, membrane ...

    African Journals Online (AJOL)

    Salt stress induced ion accumulation, ion homeostasis, membrane injury and sugar contents in salt-sensitive rice ( Oryza sativa L. spp. indica ) roots under isoosmotic conditions. ... The accumulation of sugars in PT1 roots may be a primary salt-defense mechanism and may function as an osmotic control. Key words: ...

  13. Adsorption of Acetic Acid, Cadmium ions, Lead ions and Iodine ...

    African Journals Online (AJOL)

    Michael Horsfall

    Adsorption of Acetic Acid, Cadmium ions, Lead ions and Iodine Using Activated. Carbon from Waste Wood and Rice Husks. GOODHEAD, T O; DAGDE, K K. Department of Chemical/Petrochemical Engineering, Rivers State university of Science and Technology. Port Harcourt, Nigeria. ABSTRACT: This paper presents the ...

  14. Ion implantation in Thailand (I) - development of ion implantation facilities

    International Nuclear Information System (INIS)

    Vilaithong, T.; Suwannakachorn, D.; Yotsombat, B.; Boonyawan, D.; Charoennugul, R.; Vichaisirimongkol, P.; Aumkaew, S.; A-No, V.

    1997-01-01

    Ion implantation with its many advantages has been widely and rapidly developed in the world to be a novel material treatment technique, which holds significance in both academic research and technical application. In order to develop and apply the ion implantation technique in the country, Thailand has launched a program to establish an ion beam center at Chiang Mai University. By efforts made during the past six years, the University has completed construction and installation of a 150-kV, research-purpose ion implantation facility, which consists of two beam lines - a 00 non-analyzed line and a 450 analyzed line, and which is being put into regular operation, and a 20-kV, high-current ion implanter based on a duoplasmatron ion source for non-analyzed N-ion beam implantation, and a high-intensity, multi cusp ion source for special implantation purposes. The facilities have formed powerful tools for research, teaching and engineering application, and have played an indispensable role in promoting development of novel techniques in the country

  15. Energy landscapes for mobile ions in ion conducting solids

    Indian Academy of Sciences (India)

    demonstrated here for a range of metaphosphate and diborate glasses, the complete description of the energy landscape for mobile ions also provides an effective tool for achieving a more detailed understanding of ion transport in glasses. The investigation of time evolutions can be included, if the bond valence analysis is ...

  16. ECR ion source based low energy ion beam facility

    Indian Academy of Sciences (India)

    Abstract. Mass analyzed highly charged ion beams of energy ranging from a few keV to a few. MeV plays an important role in various aspects of research in modern physics. In this paper a unique low energy ion beam facility (LEIBF) set up at Nuclear Science Centre (NSC) for providing low and medium energy multiply ...

  17. Las aristas del racismo

    Directory of Open Access Journals (Sweden)

    Fredy Rivera Vélez

    2000-01-01

    Full Text Available En el presente trabajo se estudia un ámbito que normalmente se esquiva y se enmascara: Las prácticas racistas. Esta evasión del tema se da en diferentes planos discursivos, y es una práctica, cada vez más frecuente en América Latina, pues aquí se hace de la integración étnica uno de los ejes centrales de la construcción de sus relaciones identitarias y políticas. Se propone, entonces, este trabajo develar la naturaleza y el movimiento de prácticas racistas presentes no sólo discursivamente, en la práctica política, en la práctica laboral, sino que también están presente en nuestra vida cotidiana, bajo nuevas formas y contenidos que se distancian del racismo tradicional e incorpora una nueva gramática racista, una suerte de racismo moderno, no basado en el fenotipo o características físicas como elemento central, sino en un racismo basado en la diferencia cultural, lo cual plantea un plano más excluyente, pues en este planteamiento el “objeto de racismo” no es un objeto de racismo limitado, como en el racismo tradicional, en el cual siempre es utilizado por quien practica el racismo; en el racismo contemporáneo se pretende una ruptura completa y una exclusión total del otro.

  18. Etiche del paesaggio

    Directory of Open Access Journals (Sweden)

    Massimo Venturi Ferriolo

    2015-11-01

    Full Text Available L’etica riflette sui rapporti fra uomo e ambiente. Indaga l’azione dell’uomo. Svela la sua visione della vita e il mondo possibile e accoglie in sé un complesso di norme morali e di costume che identificano un preciso comportamento nella vita di relazione. Si riferisce all’agire dell’individuo in una struttura sociale che lo comprende. Siamo alla ricerca di un’essenza del paesaggio indipendente dalla mera pittura, dalla rappresentazione, dall’immagine sentimentale: dalla natura sia ideale che reale. Prendere coscienza della cosa in sé, anche nei suoi aspetti ideali, significa comprenderne la complessità. Possiamo leggere quindi ogni paesaggio come realtà etica, risultato dell'operosità dell'uomo nella natura, ambito complessivo della vita: nel significato peculiare di progetto del mondo umano, che parte da lontano, da quando l'uomo ha incominciato a trasformare il proprio ambiente naturale per creare i luoghi dell'abitare, modellati con la mano e con lo spirito. La conoscenza dei paesaggi in tutta la loro complessità, a partire dal mondo antico, diventa quindi un nostro obiettivo. Questo significa superare, se non addirittura rovesciare, alcuni luoghi comuni consolidati e storicizzati: la teoria secondo la quale il paesaggio, nella sua dimensione estetica, sarebbe un'invenzione della modernità; il collegamento tra la moderna pittura di paesaggio e la nascita dei concetti estetici; la confusione tra natura e paesaggio, frequente nelle concezioni ecologico- ambientaliste; la tesi lessicale della nascita della coscienza del paesaggio, legata all'esistenza di una parola specifica che lo indichi. 

  19. El desarrollo del emprendedor

    OpenAIRE

    Arco Juan, Francisco Javier del

    2010-01-01

    En este trabajo pretendemos abordar el desarrollo de las competencias y de las cualidades del emprendedor. Para ello analizaremos como mediante el trabajo en equipo, el liderazgo y la toma de decisiones a la hora de elaborar un Plan de Negocio, el alumno desarrollo todas estas competencias básicas. Además, por supuesto, de la capacidad de emprender un negocio a través de las herramientas básicas para la puesta en marcha de un negocio. No data (2010) UEM

  20. El futuro del periodismo

    OpenAIRE

    Perona Páez, Juan José

    2013-01-01

    El devenir del periodismo y de la profesión periodística es una cuestión que, en plena efervescencia digital, genera recurrentes debates en torno a la influencia que ejerce la convergencia tecnológica como principal motor de cambio y transformación en el terreno de las rutinas productivas. En este sentido, una amplia mayoría de los profesionales de la noticia considera que sus efectos son muy negativos porque, además de las reconversiones y los ajustes de plantilla en buena parte de las empre...

  1. El retraso del lenguaje :

    OpenAIRE

    Rodríguez Martín, María Natividad

    2012-01-01

    La práctica educativa tiene que dar respuesta y tratamiento a casos con retraso de lenguaje, haciéndose necesaria una correcta detección, diagnóstico e intervención. Es preciso disponer de un buen marco teórico para conocer las características, clasificación y tipología, además de un modelo de evaluación y la redacción final del informe logopédico

  2. La inutilidad del etnocentrismo

    OpenAIRE

    Vanegas Betancourth, Paula C.

    2017-01-01

    El etnocentrismo como filosofía de poder en el mundo occidental. Ha evitado el exaltamiento de las mezclas culturales como opción de vida. Dándole a las minorías un lugar en los suburbios del conocimiento y de la ciencia. La exclusión de las fuentes de conocimiento primitivo por el hombre contemporáneo. Le permite la sensación de dominio sobre el mismo hombre y sobre la naturaleza. La industrialización le permitió al hombre. Como lo menciona David Dickson: « El supuesto dominio sobre la natur...

  3. El sombrero del ahogado.

    OpenAIRE

    Murillo, Javier

    2014-01-01

    Exilio y literatura parecen ir de la mano. Tal caso es el del escritor antioqueño Fernando Vallejo, quien después de dejar la casa paterna para estudiar cine en Italia, se da cuenta no sólo de que el cine es una patraña, sino que volver a su casa, a la de Medellín de su niñez, es imposible y es a través de la literatura que se deshace de todos esos recuerdos que siente que lo llevan a la tumba.

  4. La paradoja del goce

    OpenAIRE

    Sosa, María Claudia

    2015-01-01

    El éxtasis innominable, excedente e infinito se manifiesta en el cuerpo perecedero y material. Esta obra pretende ser un objeto de exploración que profundiza los límites del lenguaje; sabiendo que cualquier representación sería necia e incluso precaria. Intimando a la pregunta ¿Es el goce la herida por donde la cultura sangra su animalidad inexistente en el nombre de la pasión? Cuando estaba cursando segundo año de la Licenciatura en Artes Plásticos, hicimos una visita a la Catedral con la...

  5. Il dono del racconto

    DEFF Research Database (Denmark)

    Polito, Paola

    1998-01-01

    /racconto in prima persona d'una storia di formazione/. Dopo aver individuato, sulla base di considerazioni d'ordine tematico e quantitativo, la prevalenza di tale genere romanzesco (se pure intrecciato ad altri), se ne ricostruiscono le tracce in vari ambiti d'analisi, rilevando in particolare l......: la sua parola segue il percorso esistenziale di cui ci dà testimonianza, l'ostinata ma anche fatale formazione di sé come portavoce epico di un popolo muto e diseredato. La progressiva costituzione del senso della propria vicenda, attraverso una quête che spazia in diversi ambiti, oltre ad essere...

  6. El logotipo del Museo

    OpenAIRE

    Fundación Museo La Plata

    1993-01-01

    El actual logotipo del Museo -el anterior era un tigre de dientes de sables o Smilo- don, basado en los que yacen a ambos lados de la escalinata de acceso- nació como colaboración entre el Museo y la Facultad de Bellas Artes, que encaró varias tesis de Licenciatura en Comunicación Visual por intermedio de estudiantes que concluían la carrera. Concretado en 1988, el diseño básico aceptado abandona la representación figurativa y propone una imagen geométrica que simboliza visualmente al Museo. ...

  7. Funciones sociales del folclore

    Directory of Open Access Journals (Sweden)

    Alberto Londoño Álvarez

    1969-07-01

    Full Text Available Con el objeto de estudiar los principales aspectos sociológicos del folclore, empecemos con uno de los problemas más significativos, cual es el análisis de sus funciones que cumple en una sociedad. se trata de un asunto perteneciente al sociólogo, quien, con el propósito de mostrar al folclórogo, que su investigación no es única, porque se refiere a un hecho que pertenece al grupo de los fenómenos sociales.

  8. Trastorno del espectro autista

    OpenAIRE

    Mendoza Mendoza, María Yésica

    2012-01-01

    Se explica qué es el autismo, sus causas, tipos, síntomas, tratamiento, detección temprana, técnicas y programas específicos de intervención. A continuación, se analiza el resultado de unos cuestionarios pasados a los padres que tienen hijos con autismo para identificar y conocer el impacto de dicho trastorno en los miembros que conviven con el paciente diagnosticado de autismo y otras comorbilidades asociadas: ansiedad, presión psicológica y trastornos del estado de ánimo

  9. Al servicio del horror

    OpenAIRE

    Nebbia, José Alberto

    2016-01-01

    La acción criminal de La Nueva Provincia quedó demostrada a partir de la imputación que realizó la Unidad Fiscal de Asistencia para causas por Violaciones a los Derechos Humanos durante el Terrorismo de Estado en Bahía Blanca. Sin embargo, mientras quienes intervinieron en ese proceso son echados y denunciados penalmente, los que buscan truncar el avance sobre los responsables civiles del exterminio nos someten a una campaña que indica que, cuarenta años después, el pacto mediático-judicial p...

  10. Hospital Universidad del Norte

    Directory of Open Access Journals (Sweden)

    Luis Carlos Alvarez Barranco

    2007-01-01

    Full Text Available Objetivo: Determinar el comportamiento epidemiológico de las Infecciones de Vías Urinarias y cambios en sensibilidad y resistencia antibiótica de la Escherichia coli en el Hospital Universidad del Norte, Soledad (Atlántico, Colombia, desde enero de 2005 a diciembre de 2006. Materiales y métodos: Estudio descriptivo de tipo retrospectivo, con muestra de 537 urocultivos de pacientes que consultan al Hospital Universidad del Norte. Se evaluaron a través del recuento de unidades formadores de colonias (UFC y se analizaron los reportes de antibiogramas anotando la resistencia, sensibilidad antibiótica y evaluando el comportamiento epidemiológico de los principales antibióticos utilizados en la práctica clínica en la institución. Resultados: Distribución porcentual de infección del tracto urinario (ITU para el 2005 en mujeres: 72.9%, en hombres: 27.1%; para 2006, en mujeres 73.8% y en hombres 26.2%. Los microorganismos más frecuentemente aislados en el 2005 fueron: Escherichia coli (66.24% y Klebsiella (10.63%, y para el 2006: Escherichia coli (85 % y Proteus (5.29%. Las mayores tasas de resistencia antibiótica de Escherichia coli en el 2005 fue: ampicilina, trimetoprim sulfa y ciprofloxacina. En el 2006, el comportamiento fue similar, y hubo además disminución en la resistencia a fluoroquinolonas. Las mayores tasas de sensibilidad en el 2005 incluyen nitrofurantoína, ampicilina/sulbactam y aminoglucósidos en relación con el 2006, en el cual hubo disminución en la sensibilidad a los dos primeros. Conclusión: La ITU se presenta con más frecuencia en mujeres. La mayoría de las ITU son causada por Escherichia coli. En el 2006 disminuyó la resistencia a la ampicilina, trimetoprim sulfametaxol, cefalosporinas de primera generación y ciprofloxacina con relación al 2005. También redujeron las tasas de sensibilidad a nitrofurantoína, ampicilina/sulbactam y gentamicina.

  11. A favor del Plagio

    OpenAIRE

    Manuel Arranz

    2007-01-01

    Yo no tengo nada contra el plagio. Ustedes, como lectores, seguramente tampoco. Bueno, tal vez prejuicios. Es lógico que los tengan con tanto artículo condenándolo. Hasta ahora, que yo sepa, nadie ha escrito para defenderlo. Los que sí tienen algo, parece ser, son los autores. Una minoría al fin y al cabo. Ya sé que hay que respetar el derecho de las minorías, pero el asunto del plagio, como tantos otros, deberíamos examinarlo con más detalle, y preguntarnos, por ejemplo, ¿por qué se molestan...

  12. Debajo del hiyab

    OpenAIRE

    Villacé Martín, Sheila

    2015-01-01

    Investigación que recoge y analiza a través de una metodología cuantitativa y la técnica de encuestas, se consigue reflejar la puesta en práctica del Islam que tienen las mujeres magrebíes en Valladolid, en su inserción laboral, la legislación que existe en esta competencia y las diferentes perspectivas que existe sobre el uso de los símbolos religiosos y el choque cultural que existe. Grado en Trabajo Social

  13. Los oficios del comunicador

    OpenAIRE

    Martín-Barbero, Jesús

    2001-01-01

    En el presente ensayo se evalúan los oficios del comunicador a la luz de tres ámbitos problemáticos: las competencias y los oficios, las agencias de legitimación y las dinámicas de transformación. Se defiende la tesis de un cambio cualitativo, desde un comunicador-intermediario hacia un comunicador-mediador, que asume como base de su acción las asimetrías y las desigualdades sociales y culturales, al participar como actor en la construcción de una sociedad democrática. Se subraya en este cont...

  14. La era del youtuber

    OpenAIRE

    Sánchez Arufe, Irene

    2017-01-01

    En el trabajo se analizan los cambios que ha provocado y la recuperación que ha tenido la red social YouTube en la sociedad actual, poniendo como antecedentes la aparición de Internet y el auge de las nuevas redes sociales. También se examinan la figura del youtuber como la creación de una nueva profesión y los aspectos económicos y sociales de este nuevo trabajo. Grado en Publicidad y Relaciones Públicas

  15. emergencia del trabajo liberado

    Directory of Open Access Journals (Sweden)

    Rocío Gómez Z.

    2008-01-01

    Full Text Available Este ensayo sugiere que habría una inestimable conexión entre el compromiso subjetivo y emocional de los jóvenes usuarios de Internet, que invierten tiempo y deseo en realizar un conjunto variado de obras menores (correos electrónicos, imágenes de sí mismos en Facebook, trozos de música, mantenimiento de la bitácora en la Red, y los malestares del bienestar urbano. Estas obras menores encarnan y objetivan las demandas de trabajo liberado -frecuentemente reprimidas, pospuestas, administradas o reguladas-, que algunos de los nuevos repertorios tecnológicos canalizan y movilizan vigorosamente.

  16. Ciudades nacidas del fango

    OpenAIRE

    Blanco, Beatriz

    2017-01-01

    Este artículo es ante todo una reivindicación del urbanismo como materia compleja que se alimenta de la historia colectiva, de sus mitos y de sus aspiraciones. El urbanismo actual ha devenido en una técnica aséptica que se ocupa preferentemente de los derechos de propiedad y de la inserción de infraestructuras, pero la ciudad es un artificio sofisticado. Su entendimiento no puede conformarse con cifras, estándares e indicadores. La ciudad, como el remero en la regata, avanza mirando hacia atr...

  17. Productos derivados del chachafruto

    OpenAIRE

    Delgado González, Sebastián; González O., Edna Carolina

    2012-01-01

    Tesis (Especialista en Gerencia de Negocios Internacionales). Universidad Católica de Manizales, Universidad Jorge Tadeo Lozano, 2011. El chachafruto, también conocido en otras regiones como balú, y por su nombre genérico erythrinaedulis, integrante de la familia fabácea o leguminosas, tiene diversos usos, los cuales se resumen básicamente a la alimentación humana, mediante el procesamiento de su semilla y al consumo animal por medio del forraje o vaina. Su siembra también tiene el benefi...

  18. Fiscalidad del deporte

    OpenAIRE

    Gamazo Rubio, Isabel

    2015-01-01

    En el presente trabajo se aborda la fiscalidad deportiva analizándola sobre todo en el mundo del fútbol debido a que constituye un auténtico fenómeno de masas en España y prácticamente en todo el mundo. Ello no quiere decir que no se pueda extrapolar al resto de modalidades deportivas. Normalmente conocemos, unos más y otros menos, cómo funciona el ámbito fiscal entorno a nuestra vida, a los ingresos que percibimos por nuestro trabajo, por nuestro pequeño negocio. Pero con el deporte no oc...

  19. Ion trajectories in atom probe field ion microscopy and gas field ion sources

    CERN Document Server

    Castilho, C M C

    1999-01-01

    Trajectories of positive ions produced in a region close to a structured surface, modelled by spherical or spheroidal protrusions and kept at a positive electric potential with respect to a distant screen or detector are calculated. The results are discussed in comparison with similar practical situations produced by field ionization and field evaporation or desorption, such as those occurring in gas field ion sources, field ion microscopy and field desorption spectroscopy. (author)

  20. Upgraded vacuum arc ion source for metal ion implantation

    International Nuclear Information System (INIS)

    Nikolaev, A. G.; Oks, E. M.; Savkin, K. P.; Yushkov, G. Yu.; Brown, I. G.

    2012-01-01

    Vacuum arc ion sources have been made and used by a large number of research groups around the world over the past twenty years. The first generation of vacuum arc ion sources (dubbed ''Mevva,'' for metal vapor vacuum arc) was developed at Lawrence Berkeley National Laboratory in the 1980s. This paper considers the design, performance parameters, and some applications of a new modified version of this kind of source which we have called Mevva-V.Ru. The source produces broad beams of metal ions at an extraction voltage of up to 60 kV and a time-averaged ion beam current in the milliampere range. Here, we describe the Mevva-V.Ru vacuum arc ion source that we have developed at Tomsk and summarize its beam characteristics along with some of the applications to which we have put it. We also describe the source performance using compound cathodes.

  1. Ion energy distributions and sidewall profiles in reactive ion etching

    International Nuclear Information System (INIS)

    May, P.W.; Field, D.; Klemperer, D.F.; Song, Y.P.

    1993-01-01

    We present a brief resume of modelling of ion trajectories in radio frequency discharges of interest in reactive ion etching of semiconductors. The procedures for calculating the energies and angles at which ions strike the substrate surface are described. Examples of ion energy distributions (IEDs) and angular distributions (IADs) are given both for low pressure, collisionless-sheath plasmas, and for higher pressure conditions, where collisions significantly modify ion trajectories. Fast neutral particles formed in the sheath by collision processes are also considered. Computer modelling of the evolution of sidewall profiles during etch processes is discussed, and examples are given of profiles calculated using IED and IAD data both at low and high pressures. (orig.)

  2. Trastornos del Desarrollo y Dificultades del Aprendizaje. Primaria. Apuntes (2017)

    OpenAIRE

    Pérez Sánchez, Antonio Miguel

    2017-01-01

    El propósito de este trabajo es ofrecer al futuro Maestro en Educación Primaria, GENERALISTA, los conocimientos necesarios para afrontar los problemas relacionados con los trastornos del desarrollo y las dificultades del aprendizaje que pudieran presentar sus futuros alumnos.

  3. Negative ion adsorption by the ion source surface as a factor influencing ion lifetime measurements

    Science.gov (United States)

    Lukin, V. G.; Khvostenko, O. G.

    2017-12-01

    It is well known that negative ions formed in the gas phase through low-energy electron capture by molecules show a scatter in the measured lifetimes of their autodetachment states. In considering this question, it was found that, when using a static sector magnetic mass spectrometer, some of the ions formed on the ionization chamber walls are adsorbed and stabilized there, then joining the registered ion flux and thereby distorting their measured lifetime. Because the number of the adsorbed ions depends on the experimental conditions, their contribution to the total flux is to some extent uncontrollable—hence, the scatter.

  4. Heavy ion beam probing

    Energy Technology Data Exchange (ETDEWEB)

    Hickok, R L

    1980-07-01

    This report consists of the notes distributed to the participants at the IEEE Mini-Course on Modern Plasma Diagnostics that was held in Madison, Wisconsin in May 1980. It presents an overview of Heavy Ion Beam Probing that briefly describes the principles and discuss the types of measurements that can be made. The problems associated with implementing beam probes are noted, possible variations are described, estimated costs of present day systems, and the scaling requirements for large plasma devices are presented. The final chapter illustrates typical results that have been obtained on a variety of plasma devices. No detailed calculations are included in the report, but a list of references that will provide more detailed information is included.

  5. Fast ion atomic spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Berry, H.G.; Young, L.; Goodman, L.S.; Somerville, L.P.; Hardis, J.; Neek, D.

    1984-01-01

    We have set up two collinear fast beam/laser excitation systems, one at the Argonne Dynamitron Accelerator (0.5 to 5.0 MeV beam energy) and another at a small electrostatic accelerator (20 to 130 keV). Our objective is to study fine structure, hyperfine structure and QED effects in ions of a few electrons. Initial projects underway include studies of multi-excited transitions in Li/sup -/ and Li/sup 0/, and transitions to high Rydberg states in H/sup 0/ and He/sup 0/. We have simultaneously excited a sodium jet with a laser at the resonance wavelength (D/sub 1/ or D/sub 2/ lines) and a 1-MeV He/sup +/ beam to produce excitation to autoionizing Na and Na/sup +/ states. The Auger electron spectra are compared to spectra obtained without laser excitation, and indicate strong variations in final state populations. 17 references.

  6. Miniature Lightweight Ion Pump

    Science.gov (United States)

    Sinha, Mahadeva P.

    2010-01-01

    This design offers a larger surface area for pumping of active gases and reduces the mass of the pump by eliminating the additional vacuum enclosure. There are three main components to this ion pump: the cathode and anode pumping elements assembly, the vacuum enclosure (made completely of titanium and used as the cathode and maintained at ground potential) containing the assembly, and the external magnet. These components are generally put in a noble diode (or differential) configuration of the ion pump technology. In the present state of the art, there are two cathodes, one made of titanium and the other of tantalum. The anodes are made up of an array of stainless steel cylinders positioned between the two cathodes. All the elements of the pump are in a vacuum enclosure. After the reduction of pressure in this enclosure to a few microns, a voltage is applied between the cathode and the anode elements. Electrons generated by the ionization are accelerated toward the anodes that are confined in the anode space by the axial magnetic field. For the generation of the axial field along the anode elements, the magnet is designed in a C-configuration and is fabricated from rare earth magnetic materials (Nd-B-Fe or Sm-Co) possessing high energy product values, and the yoke is fabricated from the high permeability material (Hiperco-50A composed of Fe-Co-V). The electrons in this region collide with the gas molecules and generate their positive ions. These ions are accelerated into the cathode and eject cathode material (Ti). The neutral atoms deposit on the anode surfaces. Because of the chemical activity of Ti, the atoms combine with chemically active gas molecules (e.g. N2, O2, etc.) and remove them. New layers of Ti are continually deposited, and the pumping of active gases is thus accomplished. Pumping of the inert gases is accomplished by their burial several atomic layers deep into the cathode. However, they tend to re-emit if the entrapping lattice atoms are

  7. Heavy ion beam probing

    International Nuclear Information System (INIS)

    Hickok, R.L.

    1980-07-01

    This report consists of the notes distributed to the participants at the IEEE Mini-Course on Modern Plasma Diagnostics that was held in Madison, Wisconsin in May 1980. It presents an overview of Heavy Ion Beam Probing that briefly describes the principles and discuss the types of measurements that can be made. The problems associated with implementing beam probes are noted, possible variations are described, estimated costs of present day systems, and the scaling requirements for large plasma devices are presented. The final chapter illustrates typical results that have been obtained on a variety of plasma devices. No detailed calculations are included in the report, but a list of references that will provide more detailed information is included

  8. Review of ion accelerators

    International Nuclear Information System (INIS)

    Alonso, J.

    1990-06-01

    The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here

  9. Focused ion beam technology

    International Nuclear Information System (INIS)

    Gamo, K.

    1993-01-01

    Focussed ion beam (FIB) technology has the advantage of being a maskless process compatible with UHV processing. This makes it attractive for use in in situ processing and has been applied to the fabrication of various mesoscopic structures. The present paper reviews these results whilst putting emphasis on in situ processing by a combined FIB and molecular beam epitaxy system. The typical performance of present FIB systems is also presented. In order to utilize the potential advantages of FIB processing, reduction of damage and improvement of throughput are important, and much effort has been devoted to developing processing techniques which require a reduced dose. The importance of low-energy FIB is discussed. (author)

  10. LEXUS heavy ion collisions

    CERN Document Server

    Sang Yong Jeon

    1997-01-01

    We use a Glauber-like approach to describe very energetic nucleus- nucleus collisions as a sequence of binary nucleon-nucleon collisions. No free parameters are needed: all the information comes from simple parametrizations of nucleon-nucleon collision data. Produced mesons are assumed not to interact with each other or with the original baryons. Comparisons are made to published experimental measurements of baryon rapidity and transverse momentum distributions, negative hadron rapidity and transverse momentum distributions, average multiplicities of pions, kaons, hyperons, and antihyperons, and zero degree energy distributions for sulfur-sulfur collisions at 200 GeV/c per nucleon and for lead-lead collisions at 158 GeV/c per nucleon. Good agreement is found except that the number of strange particles produced, especially antihyperons, is too small compared with experiment. We call this model LEXUS: Linear EXtrapolation of Ultrarelativistic nucleon-nucleon Scattering to heavy ion collisions. (11 refs).

  11. Relativistic heavy ion physics

    International Nuclear Information System (INIS)

    Hill, J.C.; Wohn, F.K.

    1993-01-01

    This is a progress report for the period May 1992 through April 1993. The first section, entitled ''Purpose and Trends, gives background on the recent trends in the research program and its evolution from an emphasis on nuclear structure physics to its present emphasis on relativistic heavy ion and RHIC physics. The next section, entitled ''Physics Research Progress'', is divided into four parts: participation in the program to develop a large detector named PHENIX for the RHIC accelerator; joining E864 at the AGS accelerator and the role in that experiment; progress made in the study of electromagnetic dissociation highlight of this endeavor is an experiment carried out with the 197 Au beam from the AGS accelerator in April 1992; progress in completion of the nuclear structure studies. In the final section a list of publications, invited talks, and contributed talks is given

  12. Photo ion spectrometer

    Science.gov (United States)

    Gruen, Dieter M.; Young, Charles E.; Pellin, Michael J.

    1989-01-01

    A charged particle spectrometer for performing ultrasensitive quantitative analysis of selected atomic components removed from a sample. Significant improvements in performing energy and angular refocusing spectroscopy are accomplished by means of a two dimensional structure for generating predetermined electromagnetic field boundary conditions. Both resonance and non-resonance ionization of selected neutral atomic components allow accumulation of increased chemical information. A multiplexed operation between a SIMS mode and a neutral atomic component ionization mode with EARTOF analysis enables comparison of chemical information from secondary ions and neutral atomic components removed from the sample. An electronic system is described for switching high level signals, such as SIMS signals, directly to a transient recorder and through a charge amplifier to the transient recorder for a low level signal pulse counting mode, such as for a neutral atomic component ionization mode.

  13. Review of ion accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, J.

    1990-06-01

    The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here.

  14. Mejora del cumplimiento con hipolipemiantes

    Directory of Open Access Journals (Sweden)

    Andrés Iglesias JC

    2009-12-01

    Full Text Available INTRODUCCIÓN La baja adherencia en el cumplimiento farmacoterapéutico de los pacientes en tratamiento con estatinas compromete la efectividad de la terapia hipolipemiante. El objetivo del estudio fue evaluar la intervención del farmacéutico, mediante acciones de educación para la salud (EpS en la dispensación, en el cumplimiento del tratamiento con estatinas y en el conocimiento de la enfermedad y del tratamiento por parte de los pacientes. MÉTODOS Estudio experimental controlado y aleatorizado realizado en 10 farmacias comunitarias de la provincia de Pontevedra a 124 pacientes en tratamiento con estatinas. En el grupo intervención (GI se realizó una dispensación protocolizada y EpS y en el grupo control (GC una entrega “habitual” de medicamentos. Se midió el cumplimiento farmacoterapéutico con estatinas a los 2 meses y al final del estudio, el conocimiento de la enfermedad y del tratamiento al inicio y al final, y las modificaciones en el estilo de vida después de la intervención. RESULTADOS 102 pacientes terminaron el estudio. En el global del estudio, en el GC fue cumplidor el 68,0% y en el GI el 90,4% (p = 0,005. El conocimiento de los pacientes del GC al final del estudio fue de 12,7 ± 1,9 puntos y de 14,2 ± 1,9 puntos en el GI (p<0,001. No hubo modificaciones en el estilo de vida de los pacientes. CONCLUSIONES La intervención educativa del farmacéutico durante la dispensación logra un mejor cumplimiento en el tratamiento con estatinas y mejora el conocimiento de la hipercolesterolemia y de su tratamiento por parte del paciente.

  15. Heavy ion driver technology

    International Nuclear Information System (INIS)

    Keefe, D.

    1988-09-01

    Major differences between fusion drivers and traditional accelerators include the following. The final beam current needed (/approximately/20 kA in a short pulse) is very much larger for a driver; such beams are dominated by repulsive space-charge effects since, even at 10 GeV, the ions are non-relativistic (v/c = 0.3). Also, the optical quality of the beams (called emittance by accelerator people) must be extremely good to ensure a suitably small focal spot at the pellet. Two schemes, one with a rf linac and storage rings, the other with a single-pass current-amplifying induction linac, are under study, the latter exclusively in the US. The induction linac approach lends itself to an examination in a sequence of scaled-down laboratory experiments since the most difficulties are expected to occur at the low energy end. Experiments and simulation have centered on a study of the transverse and longitudinal control of space-charge-dominated beams which are best described in terms of a non-neutral plasma rather than the traditional single-particle dynamics picture. An understanding of the high-current instability limits is required for arriving at a safe driver design. The final on-target beam current is so high that it must be carried in 16 separate focusing channels leading into the combustion chamber. While the energy deposition of the ions is expected to be entirely classical, there is a wealth of plasma physics phenomena to be explored (by theory and simulation) in the final propagation of these beams through the low-density gas in the chamber and in the environment of the hot target; it is important that none of these could result in a significant portion of the beam missing the focal spot. 13 refs., 9 figs., 1 tab

  16. Formation of Ion Phase-Space Vortexes

    DEFF Research Database (Denmark)

    Pécseli, Hans; Trulsen, J.; Armstrong, R. J.

    1984-01-01

    The formation of ion phase space vortexes in the ion two stream region behind electrostatic ion acoustic shocks are observed in a laboratory experiment. A detailed analysis demonstrates that the evolution of such vortexes is associated with ion-ion beam instabilities and a nonlinear equation for ...

  17. Ion beams in materials processing and analysis

    CERN Document Server

    Schmidt, Bernd

    2012-01-01

    This book covers ion beam application in modern materials research, offering the basics of ion beam physics and technology and a detailed account of the physics of ion-solid interactions for ion implantation, ion beam synthesis, sputtering and nano-patterning.

  18. RASGOS GEOGRÁFICOS DEL VALLE DEL RIO AGRIO INFERIOR.

    Directory of Open Access Journals (Sweden)

    Celia Torren

    1993-12-01

    Full Text Available El presente artículo es una síntesis del trabajo "Rasgos Geográficos del Valle del Río Agrio Inferior, el cual es un estudio de base para el conocimiento de la geografía de la región: - apoyando el esfuerzo que está realizando la población del área para lograr una identidad propia y una definitiva integración al contexto provincial; - aportando al proyecto "Rescate Arqueológico en Quili Malal, Neuquén" (subsidiado por CONICET y UNESCO, cuya dirección está a cargo de la profesora Susana Rodríguez de la U.N.C., a través de la confección del mapa geomorfológico del área; y - contribuyendo a los estudios que resultan necesarios ante la construcción de una obra hidroeléctrica de la magnitud de "El Chihuido I", emprendimiento que será llevado a cabo por Agua y Energía eléctrica de la Nación. Los límites del área estudiada fueron establecidos teniendo en cuenta el área del valle inferior del Río Agrio que será completamente inundada por el futuro embalse de la represa "El Chihuido I", a emplazarse 5,5 Km aguas abajo de la confluencia de los ríos Agrio y Neuquén. Además de esta área de afectación directa se tomó también una zona de perilago estrechamente vinculada a la anterior. De esta manera los límites este y oeste quedaron establecidos por la confluencia de los ríos antes mencionados y la localidad de Bajada del Agrio, respectivamente.

  19. Lithium ion storage between graphenes

    Directory of Open Access Journals (Sweden)

    Chan Yue

    2011-01-01

    Full Text Available Abstract In this article, we investigate the storage of lithium ions between two parallel graphene sheets using the continuous approximation and the 6-12 Lennard-Jones potential. The continuous approximation assumes that the carbon atoms can be replaced by a uniform distribution across the surface of the graphene sheets so that the total interaction potential can be approximated by performing surface integrations. The number of ion layers determines the major storage characteristics of the battery, and our results show three distinct ionic configurations, namely single, double, and triple ion forming layers between graphenes. The number densities of lithium ions between the two graphenes are estimated from existing semi-empirical molecular orbital calculations, and the graphene sheets giving rise to the triple ion layers admit the largest storage capacity at all temperatures, followed by a marginal decrease of storage capacity for the case of double ion layers. These two configurations exceed the maximum theoretical storage capacity of graphite. Further, on taking into account the charge-discharge property, the double ion layers are the most preferable choice for enhanced lithium storage. Although the single ion layer provides the least charge storage, it turns out to be the most stable configuration at all temperatures. One application of the present study is for the design of future high energy density alkali batteries using graphene sheets as anodes for which an analytical formulation might greatly facilitate rapid computational results.

  20. Propagation of Ion Acoustic Perturbations

    DEFF Research Database (Denmark)

    Pécseli, Hans

    1975-01-01

    Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered.......Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered....

  1. Spacecraft ion beam noise effects

    Science.gov (United States)

    Anenberg, G. L.

    1972-01-01

    An estimate of the antenna noise temperature and the uplink signal-to-noise ratio has been made for Bremsstrahlung radiation emitted by a spacecraft ion beam; a worst-case situation in which the spacecraft antenna is located in the exit plane of the ion beam and directed at varying angles into the ion beam is assumed. Numerical results of the antenna noise temperature versus antenna pointing angle are given for a typical set of ion beam and antenna pattern parameters. The uplink signal-to-noise ratio due to the ion beam noise alone is given in terms of a critical range in AU at which a typical ranging transmission is received with S/N = 0 db. The effects of the ion beam divergence angle and antenna distance on the ion beam are also presented. Results of the study show typical increases in the antenna noise temperature of about 0.2 K and critical ranges of the order of 3-5 AU. An ion engine thus generally introduces an undetectable level of noise into a spacecraft receiver.

  2. SPS Ion Induced Desorption Experiment

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    This experiment will give a study about the induced desorption from heavy ion (Indium ion run from week 45 in SPS T4-H8 area) impacting LHC type graphite collimator. 4 different samples are located in the 4 chambers 90° one to each other: pure graphite, graphite with copper coating, graphite with NEG coating, 316LN stainless steal (reference).

  3. Bundle Security Protocol for ION

    Science.gov (United States)

    Burleigh, Scott C.; Birrane, Edward J.; Krupiarz, Christopher

    2011-01-01

    This software implements bundle authentication, conforming to the Delay-Tolerant Networking (DTN) Internet Draft on Bundle Security Protocol (BSP), for the Interplanetary Overlay Network (ION) implementation of DTN. This is the only implementation of BSP that is integrated with ION.

  4. High Resolution Scanning Ion Microscopy

    NARCIS (Netherlands)

    Castaldo, V.

    2011-01-01

    The structure of the thesis is the following. The first chapter is an introduction to scanning microscopy, where the path that led to the Focused Ion Beam (FIB) is described and the main differences between electrons and ion beams are highlighted. Chapter 2 is what is normally referred to (which I

  5. Hooded arc ion-source

    CERN Multimedia

    CERN PhotoLab

    1972-01-01

    The positioning system for the hooded arc ion-source, shown prior to mounting, consists of four excentric shafts to locate the ion-source and central electrodes. It will be placed on the axis of the SC and introduced into the vacuum tank via the air locks visible in the foreground.

  6. Heavy-ion superconducting linacs

    International Nuclear Information System (INIS)

    Delayen, J.R.

    1989-01-01

    This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs

  7. Targets for heavy ion fusion

    International Nuclear Information System (INIS)

    Clauser, M.J.

    1978-01-01

    This paper describes some of the basic principles of fusion target implosions, using some simple targets designed for irradiation by ion beams. Present estimates are that ion beams with 1-5 MJ, and 100-500 TW will be required to ignite high gain targets. (orig.) [de

  8. in heavy-ion collisions

    Indian Academy of Sciences (India)

    2015-05-06

    May 6, 2015 ... the 'Big Bang', and has now been (re-)created as the hottest matter ever in laboratory by heavy-ion collisions ('Little Bang') at the Relativistic Heavy Ion Collider (RHIC) as well as at the Large Hadron Collider (LHC). To experimentally measure and theoretically understand the various properties of the QGP ...

  9. Project of an ion thruster

    International Nuclear Information System (INIS)

    Perche, G.E.

    1983-07-01

    The mercury bombardment electrostatic ion thruster is the most successful electric thruster available today. This work describes a 5 cm diameter ion thruster with 3.000 s specific impulse and 5 mN thrust. The advantages of electric propulsion and the tests that will be performed are also presented. (Author) [pt

  10. Quantum computing with trapped ions

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, R.J.

    1998-01-01

    The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

  11. Variables moderadoras del estres

    Directory of Open Access Journals (Sweden)

    María Cristina Richaud de Minzi

    1999-01-01

    Full Text Available El objetivo del presente trabajo es analizar la influenciadel estilo atribucional, la confianza interpersonal y el soporte social sobre la percepción de la amenaza. Se administraron la Escala de Estilo Atribucional; la Manheim Interview 01 Social Support, la Escala de Confianza Interpersonal; y el Inventario de Situaciones y Respuestas de Ansiedad, a 260 sujetos de ambos sexos, de 30 años de edad promedio, de nivel socioeconómico medio, residentes en la ciudad de Buenos Aires. El soporte social no demostró influencia significativa sobre la percepción de la amenaza. Con respecto a la influencia del estilo atribucional se puede decir que las personas indefensas perciben más amenaza, especialmente expresada como ansiedad cognitiva y, en menor grado, como ansiedad motora o conductual. La confianza interpersonal demostró ser una variable importante en la percepción de la amenaza. Los sujetos que presentaron alta desconfianza hacia las personas de su entorno perciben un mundo amenazante, que se manifiesta como ansiedad cognitiva, fisiológica y motora o conductual.

  12. RECUERDOS DEL SIGLO XX

    Directory of Open Access Journals (Sweden)

    ASUNCIÓN LAVRIN

    2011-10-01

    Full Text Available Este ensayo hace una revisión de conceptos clave en la educación de la mujer en Hispanoamérica, en la primera mitad del siglo XX, y el debate sobre la educación superior de la mujer. También analiza las ideas de Gabriela Mistral para la educación femenina en su Lectura para mujeres, y las compara con las de la escritora mexicana Rosario Castellanos. Finalmente, hace un llamado por nuevos modelos educativos para la mujer de siglo XXI.Este ensayo hace una revisión de conceptos clave en la educación de la mujeren Hispanoamérica, en la primera mitad del siglo XX, y el debate sobre laeducación superior de la mujer. También analiza las ideas de Gabriela Mistralpara la educación femenina en su Lectura para mujeres, y las comparacon las de la escritora mexicana Rosario Castellanos. Finalmente, hace unllamado por nuevos modelos educativos para la mujer de siglo XXI.

  13. Gerencia del Siglo XXI

    Directory of Open Access Journals (Sweden)

    John Orlando Crissien Castillo

    2013-07-01

    Full Text Available El cambio es más rápido que nunca, la tecnología genera nuevos modelos gerenciales, los mercados se abren, el paradigma de la competitividad y la productividad. Los gerentes modernos estamos expuestos a muchas presiones generadoras de estrés; hecho que, según la OMS (Organización Mundial de la  alud, está entre las tres enfermedades que cobran más muertes en el mundo. EL campo de juego gerencial ha cambiado: por ende la gerencia del siglo XXI requiere un perfil de administrador-gerente diferente. Este nuevo gerente se debe tornar líder y administrador. Las cosas se administran, la gente se lidera, se gerencia. Por esto el gerente líder del siglo XXI se debe formar, capacitar, entrenar en aquellas habilidades-competencias requeridas por este nuevo entorno. Por tal razón debe generar dos sets de competencias: las de gerente integral y el desarrollo de la capacidad directiva.

  14. [Feminismes del segle XXI

    Directory of Open Access Journals (Sweden)

    Pilar Rahola

    2013-07-01

    Full Text Available Las dos mujeres invitadas a la presentación de Lectora 11 arrojan luz sobre la continua invisibilidad de las mujeres y sus sufrimientos. Mientras que Pilar Rahola subraya las consecuencias del racismo sexual (una segregación absoluta, dependencia femenina e incluso esclavitud, situaciones en las que se encuentran unas 700 millones de mujeres en el mundo entero, Carme Valls explica que en el mundo de la medicina, aún dominado por los hombres, las mujeres y sus enfermedades siguen siendo ignoradas. Las mujeres son víctimas de su cuerpo, lo cual ha consittido una excelente excusa para los hombres para convertir a las mujeres en seres inferiores que necesitan ser controladas. Sin embargo, la salud mental de las mujeres se ve incluso más afectada, a causa de la incompatibilidad entre las mujeres reales y los roles femeninos que la imaginación masculina les ha creado. A pesar de que la tecnología moderna ofrece la posibilidad de obtener información en cada momento y en cada rincón del mundo, las mujeres siguen sin ser escuchadas.

  15. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available Refiere el Informe Nacional de Brasil sobre el Diagnóstico de la Comunicación en América Latina en el que se analizan los más importantes medios de comunicación de ese país. En el artículo de opinión se reflexiona sobre los cambios que sufre la comunicación política en la región como resultado de nuevos protagonistas con nuevos mensajes como: Hugo Chávez, Venezuela, Bucarám, Ecuador y Fujimori, Perú. Describe dos noticias que han llamado la atención: la desinformación en la campaña electoral de los Estados Unidos y el peculiar sistema de comunicación del Presidente Chávez para mantener la popularidad. En cultura para la imagen periodística impresa o Infografía muestra los esfuerzos que la prensa diría del mundo entero hace para competir en cuanto a imagen con la televisión. Se trata la elaboración de los guiones cinematográficos y en Comunicación Institucional se responde a cómo a solucionar los problemas de un banco desde Argentina.

  16. Fundamentos del metodo cientifico

    Directory of Open Access Journals (Sweden)

    Badii, M. H.

    2004-01-01

    Full Text Available El objetivo de esta obra no radica en realizar una búsqueda exhaustiva de la literatura en el tema, sino, sentar las bases del método científico, notando los aspectos filosóficos e éticos de la ciencia. Se presentan los conceptos y definiciones fundamentales relacionados con la metodología de la investigación científica. Se maneja el concepto de la toma de los datos válidos como un requisito básico en cualquier trabajo científico. Se pone a disposición del lector un modelo denominado el ECOEE que es una herramienta poderosa para establecer puntos de comparación e discusión entre los resultados de diferentes trabajos científicos. Finalmente, ofrece unas sugerencias de que hacer o no hacer en cuanto a realizar un trabajo de investigación.

  17. El mundo del arte

    Directory of Open Access Journals (Sweden)

    Arthur Danto

    2013-12-01

    Full Text Available [ES] Este famoso ensayo de Arthur Danto, que se presenta aquí traducido al español, fue el primer desarrollo de su concepto de «mundo del arte» como un marco contextual que da sentido, por medio de sus usos teóricos-lingüísticos, a toda forma de arte reconocible en el mundo. Este concepto tendría una influencia enorme en todo el mundo, y fue la base de todo el pensamiento posterior de Danto acerca del arte, y su principal herramienta filosófica para vender en todas partes la idea de que las obras de Andy Warhol no sólo eran legítimas obras de arte, sino incluso, obras importantes de arte. ; [EN] This famous essay by Arthur Danto, presented here entirely translated into Spanish, was the first development of his concept of “art world” as a contextual framework that gives meaning, through its theoretical-linguistic uses, to all forms of recognizable art in the world. This concept would have a huge influence around the world, and was the basis of all subsequent Danto’s thought about art, and his main philosophical tool to sell everywhere the idea that the works of Andy Warhol were not only legitimate works of art, but even important works of art.

  18. Incorrecciones del habla infantil

    Directory of Open Access Journals (Sweden)

    María del Pino LECUONA NARANJO

    2009-11-01

    Full Text Available En el presente trabajo se pretende dar una visión de algunos rasgos característicos del lenguaje infantil, centrándonos especialmente en el estudio de los niños de 4 a 6 años de edad. Es pues, su finalidad fundamental la descripción y análisis de los rasgos que se pueden observar en la expresión verbal de los preescolares. Las diversas peculiaridades que van a ser objeto de examen se refieren a la emisión de incorrecciones de carácter fonético, morfológico y semántico. El análisis unificado de estos tres factores responde a la consideración de que todos surgen como consecuencia de un proceso de simplificación lingüística originado por un estado inconcluso de desarrollo del lenguaje.

  19. Carta del editor

    Directory of Open Access Journals (Sweden)

    Juan Braun

    2015-01-01

    Full Text Available Muchos millones de latinoamericanos son pobres y necesitan educación. Los medios de comunicación públicos y privados deben responsabilizarse y ayudar a la erradicación del analfabetismo. El desarrollo del potencial humano debe ser una prioridad de toda la sociedad, pues es el único camino hacia la evolución de la esperanza. Aprendizaje, Educación no formal. Veinte años de lenguaje total, Educación indígena, Alfabetización,son artículos contenidos en el módulo Educación para todos. Se añaden dos entrevistas al jesuita Attilio Hartamnn y Monseñor José Joaquín Salcedo, colombiano de Radio Sutatenza, dos vidas dedicadas a la educación de los más pobres. En el módulo de Comunicación e Integración escriben varios comunicólogos sobre la necesidad de integración de los pueblos de América Latina. Otro artículo trata el Periodismo Cultural

  20. El lactato como posible factor del mecanismo de fatiga muscular.

    OpenAIRE

    José Carlos Giraldo T.; María Elena Sánchez

    2009-01-01

    Se revisa el papel del lactato en la función muscular. Se destacan los siguientes conceptos: el lactato es un intermediario metabólico que aumenta durante el ejercicio de alta intensidad, como consecuencia de la elevada actividad glicolítica. En esas condiciones la formación de ATP se asocia con generación de iones lactato e H+ y se reduce el pH de la célula activa. Si hay fatiga, el aumento en los niveles de lactato se correlaciona con la magnitud en la caída de la fuerza y los niveles de la...

  1. LA ESCRITURA DEL MUNDO

    Directory of Open Access Journals (Sweden)

    Ángel Martínez García-Posada

    2010-05-01

    Full Text Available RESUMEN El mapa de un arquitecto es un paisaje alternativo, una representación intencionada del medio que se aleja del documento impuesto y apunta la posibilidad de transformarlo, así comienza el proyecto; el sentido inverso, llevar al territorio los signos del plano, remite a la esencia de la arquitectura y su capacidad de alterar el mundo. Nuestras representaciones describen una realidad y a su vez son otra distinta, entre ambos campos se produce un flujo que los liga y los condiciona. La cartografía está relacionada con la idea de microcosmos, la arquitectura tiene algo de descripción del universo a través de fragmentos concretos. A veces es necesario distanciarse para comprenderlo; otras, la extrapolación a partir de una pequeña conquista permite modificarlo desde límites que apenas se alejan de nuestro cuerpo. Acaso proyectar consista en encontrar la distancia adecuada. La mirada sensible del arquitecto traza asociaciones y planifica encuentros, en el plano de su mesa conviven trabajos en desarrollo de escalas diversas con proyectos ajenos e ideas propias, en esta contigüidad comienzan a surgir relaciones. Para un arquitecto, que al proyectar describe realidades todavía inexistentes, los proyectos y las investigaciones son un lugar para la especulación y la mirada personal. Lectura y escritura constituyen un proceso continuo y creador.SUMMARY The map of an architect is an alternative landscape, a deliberate representation of the environment which moves away from the imposed document and points out the possibility to transform it, thus begins the project. The inverse sense, to take the contents of the plan to the land, transmits the essence of architecture and its capacity to alter the world. Our representations describe one reality, whilst being of another, a flow takes place between both fields that ties and determines them. Cartography is related to the microcosm idea, architecture has something of the description of the

  2. Ion-Molecule Reaction Dynamics.

    Science.gov (United States)

    Meyer, Jennifer; Wester, Roland

    2017-05-05

    We review the recent advances in the investigation of the dynamics of ion-molecule reactions. During the past decade, the combination of single-collision experiments in crossed ion and neutral beams with the velocity map ion imaging detection technique has enabled a wealth of studies on ion-molecule reactions. These methods, in combination with chemical dynamics simulations, have uncovered new and unexpected reaction mechanisms, such as the roundabout mechanism and the subtle influence of the leaving group in anion-molecule nucleophilic substitution reactions. For this important class of reactions, as well as for many fundamental cation-molecule reactions, the information obtained with crossed-beam imaging is discussed. The first steps toward understanding micro-solvation of ion-molecule reaction dynamics are presented. We conclude with the presentation of several interesting directions for future research.

  3. RHIC heavy ion operations performance

    CERN Document Server

    Satogata, T; Ferrone, R; Pilat, F

    2006-01-01

    The Relativistic Heavy Ion Collider (RHIC) completed its fifth year of operation in 2005, colliding copper ion beams with ps=200 GeV/u and 62.4 GeV/u[1]. Previous heavy ion runs have collided gold ions at ps=130 GeV/u, 200 GeV/u, and 62.4 GeV/u[2], and deuterons and gold ions at ps=200 GeV/u[3]. This paper discusses operational performance statistics of this facility, including Cu- Cu delivered luminosity, availability, calendar time spent in physics stores, and time between physics stores. We summarize the major factors affecting operations efficiency, and characterize machine activities between physics stores.

  4. Ion bombardment modification of surfaces

    International Nuclear Information System (INIS)

    Auciello, O.

    1984-01-01

    An historical overview of the main advances in the understanding of bombardment-induced surface topography is presented. The implantation and sputtering mechanisms which are relevant to ion bombardment modification of surfaces and consequent structural, electronic and compositional changes are described. Descriptions of plasma and ion-beam sputtering-induced film formation, primary ion-beam deposition, dual beam techniques, cluster of molecule ion-beam deposition, and modification of thin film properties by ion bombardment during deposition are presented. A detailed account is given of the analytical and computational modelling of topography from the viewpoint of first erosion theory. Finally, an account of the possible application and/or importance of textured surfaces in technologies and/or experimental techniques not considered in previous chapters is presented. refs.; figs.; tabs

  5. Ion sources for electrostatic accelerators

    International Nuclear Information System (INIS)

    Hellborg, R.

    1998-01-01

    Maybe the most important part of an electrostatic accelerator system, and also often the most tricky part is the ion source. There has been a rapid growth in activity in ion-source research and development during the last two to three decades. Some of these developments have also been of benefit to electrostatic accelerator users. In this report some of the different types of ion sources used in electrostatic accelerators are described. The list is not complete but more an overview of some of the more commonly used sources. The description is divided into two groups; positive ion sources for single stage electrostatic accelerators and negative ion sources for two stages (i.e. tandem) accelerators

  6. Isochronous cyclotrons. Multicharged ion accelerators

    International Nuclear Information System (INIS)

    Shelaev, I.A.

    1976-01-01

    Isochronous cyclotrons for heavy ions are considered. A development of the heavy ion acceleration technique is discussed. The advantages of heavy ion acceleration by means of the isochronous cyclotron in the energy range up to 10 MeV/nucleon are shown. The requirements to an increase of the beam intensity and decrease of the accelerator dimensions are determined. A considerable increase in the beam intensity is achieved in cascade accelerators of heavy ions. Various schemes of such accelerators are considered, and their parameters are given. To obtain the nuclei with energy of 10 GeV/nucleon and higher, some accelerating complexes are projected, e.g. nuclotrons, where the superconducting magnets are supposed to be used. New methods for heavy ion acceleration are worked out, especially, the collective methods of acceleration

  7. The ATLAS positive ion injector

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Bollinger, L.M.; Pardo, R.C.

    1990-01-01

    This paper reviews the design, construction status, and beam tests to date of the positive ion injector (PII) which is replacing the tandem injector for the ATLAS heavy-ion facility. PII consists of an ECR ion source on a 350 KV platform injecting a very low velocity superconducting linac. The linac is composed of an independently-phased array of superconducting four-gap interdigital resonators which accelerate over a velocity range of .006 to .05c. In finished form, PII will be able to inject ions as heavy as uranium into the existing ATLAS linac. Although at the present time little more than 50% of the linac is operational, the indenpently-phased array is sufficiently flexible that ions in the lower half of the periodic table can be accelerated and injected into ATLAS. Results of recent operational experience will be discussed. 5 refs.

  8. The ATLAS positive ion injector

    International Nuclear Information System (INIS)

    Shepard, K.W.; Bollinger, L.M.; Pardo, R.C.

    1990-01-01

    This paper reviews the design, construction status, and beam tests to date of the positive ion injector (PII) which is replacing the tandem injector for the ATLAS heavy-ion facility. PII consists of an ECR ion source on a 350 KV platform injecting a very low velocity superconducting linac. The linac is composed of an independently-phased array of superconducting four-gap interdigital resonators which accelerate over a velocity range of .006 to .05c. In finished form, PII will be able to inject ions as heavy as uranium into the existing ATLAS linac. Although at the present time little more than 50% of the linac is operational, the indenpently-phased array is sufficiently flexible that ions in the lower half of the periodic table can be accelerated and injected into ATLAS. Results of recent operational experience will be discussed. 5 refs

  9. Los signos del alfabeto griego

    OpenAIRE

    Calero-Secall, Ines Maria

    1994-01-01

    A través de este trabajo estudiamos cada una de las letras del alfabeto griego en lo que se refiere a su origen, nombres, valores, grafías y en cuanto a las confusiones fonéticas en las que incurrieron los griegos cuando la adopción del alfabeto semítico tuvo lugar.

  10. La presidencia del Consejo Europeo

    OpenAIRE

    Mangas, Araceli

    2016-01-01

    Este trabajo analiza las funciones de la presidencia estable del Consejo europeo tras la reforma del Tratado de Lisboa, los caracteres, la legitimidad, la representación exterior y las relaciones inter-institucionales, su infraestructura administrativa y su responsabilidad.

  11. Una perspectiva del Banco Mundial

    OpenAIRE

    Berry, Joanna de

    2016-01-01

    El Banco Mundial aporta cualidades características al papel que puede desempeñar en promover la transición del ámbito humanitario al del desarrollo y está aumentando de manera significativa su compromiso con el desplazamiento forzado.

  12. Tratamiento del paciente con artrosis

    Directory of Open Access Journals (Sweden)

    Francisco Vargas Negrín

    2014-01-01

    Full Text Available El manejo terapéutico del paciente con artrosis tiene como objetivo disminuir la sintomatología dolorosa e inflamatoria, mejorar la capacidad funcional del paciente y la aplicación de intervenciones terapéuticas eficaces y lo más seguras posibles. Un enfoque centrado en el paciente implica su participación activa en el diseño del plan terapéutico y en la toma de decisiones informadas oportunas en todas las etapas de la enfermedad. La educación terapéutica, la actividad física y el ejercicio terapéutico junto con el control de peso, en caso de sobrepeso u obesidad, constituyen el núcleo central del tratamiento. Los autocuidados individuales y por los familiares son fundamentales en el control del día a día del paciente. El uso de terapias físicas, ayudas técnicas (bastón, etc. y de fármacos tipo analgésicos simples, opioides y antiinflamatorios tiene evidencias demostradas en el control del dolor, mejora la funcionalidad y la calidad de vida del paciente y una clara recomendación de uso en el tratamiento de la artrosis. La cirugía conservadora y la de reemplazo articular se indican en los casos en los que no se logran los objetivos terapéuticos en casos concretos.

  13. El Derecho universal del Trabajo

    Directory of Open Access Journals (Sweden)

    Héctor-Hugo Barbagelata

    2014-01-01

    Full Text Available La idea de un derecho universal del trabajo no es nueva, en realidad es más antigua quela legislación del trabajo y por lo tanto, más antigua que la propia rama del derecho que estudia estas cuestiones.Sí, son nuevos los avances que con ese objetivo se han ido registrando desde fines del siglo pasado.I- Introducción.- II Antecedentes.- II Constitucionalización e internacionalización.- IV Principios y criterios de interpretación del bloque de constitucionalidad.- A Criterio fundado en las condiciones del Estado Social de Derecho; B Principio de complementariedad e interdependencia de todas las normas sobre derechos humanos; C Primacía de la disposición más favorable a la persona humana; D Criterio resultante del principio de progresividad.; E Principio de irreversibilidad o de no regresión. F Principio de autoejecución y autoaplicación..- V Conflictos entre los derechos fundamentales .- VI.- Los principios filosóficos: a La Justicia social ; b La especificidad del trabajo humano; c Reafirmación de la dignidad de la persona humana; VII Conclusiones. 

  14. ECONOMIA POLITICA DEL PLAN COLOMBIA

    Directory of Open Access Journals (Sweden)

    Jesús Martínez Betancourt

    2000-05-01

    Full Text Available 1. El Plan Colombia, una política imperialista. El verdadero plan de desarrollo de Colombia no es el que aprobó el Congreso de la República en octubre del año pasado, sino el que se deriva de los acuerdos sobre créditos y “ayudas” del Gobierno del Dr. Pastrana con el Fondo Monetario Internacional, con el Banco Interamericano de Desarrollo y especialmente con el Gobierno de los Estados Unidos, ya conocido como Plan Colombia. Una de las características del imperialismo, formuladas por V. I. Lenin en su libro “El imperialismo fase superior del capitalismo”, de vigencia en este mundo globalizado por la hegemonía ultraimperialista, es que simultáneamente con el reparto económico del mundo se hace el reparto territorial, para afianzar el dominio económico, cultural y político. El reparto territorial fundamentado en las pretensiones económicas, por las fuentes de materias primas y alimentos y/o por mercados para vender los productos de las metrópolis, generalmente se ha hecho por la vía bélica, como las dos guerras mundiales del siglo XX, o las regionales, como la del Golfo Pérsico, entre otras.

  15. Taquicardias supraventriculares. Estado del arte

    Directory of Open Access Journals (Sweden)

    Jairo Alfonso Gándara Ricardo

    2016-01-01

    El tratamiento de las taquicardias supraventriculares dependerá del estado hemodinámico del paciente, el cual definirá el requerimiento de terapia eléctrica o tratamiento médico. Se debe hacer una selección adecuada de los pacientes que requieren estudio electrofisiológico y ablación.

  16. Response of thermal ions to electromagnetic ion cyclotron waves

    Science.gov (United States)

    Anderson, B. J.; Fuselier, S. A.

    1994-01-01

    Electromagnetic ion cyclotron waves generated by 10 - 50 keV protons in the Earth's equatorial magnetosphere will interact with the ambient low-energy ions also found in this region. We examine H(+) and He(+) distribution functions from approx. equals 1 to 160 eV using the Hot Plasma Composition Experiment instrument on AMPTE/CCE to investigate the thermal ion response to the waves. A total of 48 intervals were chosen on the basis of electromagnetic ion cyclotron (EMIC) wave activity: 24 with prevalent EMIC waves and 24 with no EMIC waves observed on the orbit. There is a close correlation between EMIC waves and perpendicular heated ion distributions. For protons the perpendicular temperature increase is modest, about 5 eV, and is always observed at 90 deg pitch angles. This is consistent with a nonresonant interaction near the equator. By contrast, He(+) temperatures during EMIC wave events averaged 35 eV and sometimes exceeded 100 eV, indicating stronger interaction with the waves. Furthermore, heated He(+) ions have X-type distributions with maximum fluxes occurring at pitch angles intermediate between field-aligned and perpendicular directions. The X-type He(+) distributions are consistent with a gyroresonant interaction off the equator. The concentration of He(+) relative to H(+) is found to correlate with EMIC wave activity, but it is suggested that the preferential heating of He(+) accounts for the apparent increase in relative He(+) concentration by increasing the proportion of He(+) detected by the ion instrument.

  17. Ions kinematics in an electrostatic ion beam trap

    Energy Technology Data Exchange (ETDEWEB)

    Attia, D

    2004-06-01

    In this study, I have tried to provide a better understanding of the dynamics of ions inside an electrostatic ion beam trap. The electrostatic ion trap allows to store ions moving between two electrostatic mirrors. Although the trap has been developed already seven years ago, no direct measurement of the transversal velocity distribution of the ions has been performed. Such quantity is central for understanding the conditions under which a beam should be produced (mainly emittance) in order to be trapped by such a device. The data I have obtained during the course of this work are based on an experimental technique which relies on the direct imaging of the particles exiting the trap, as well as on numerical simulations of the ion trajectories inside the trap. I have personally been involved in the hardware development of the imaging system, the data acquisition and analysis of the data as well as il all numerical calculations presented here. These results allow us to obtain, for the first time, experimental information on the transverse phase space of the trap, and contribute to the overall understanding of the ion motion in this system. (author)

  18. Ion Rings for Magnetic Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Greenly, John, B.

    2005-07-31

    This Final Technical Report presents the results of the program, Ion Rings for Magnetic Fusion, which was carried out under Department of Energy funding during the period August, 1993 to January, 2005. The central objective of the program was to study the properties of field-reversed configurations formed by ion rings. In order to reach this objective, our experimental program, called the Field-reversed Ion Ring Experiment, FIREX, undertook to develop an efficient, economical technology for the production of field-reversed ion rings. A field-reversed configuration (FRC) in which the azimuthal (field-reversing) current is carried by ions with gyro-radius comparable to the magnetic separatrix radius is called a field-reversed ion ring. A background plasma is required for charge neutralization of the ring, and this plasma will be confined within the ring's closed magnetic flux. Ion rings have long been of interest as the basis of compact magnetic fusion reactors, as the basis for a high-power accelerator for an inertial fusion driver, and for other applications of high power ion beams or plasmas of high energy density. Specifically, the FIREX program was intended to address the longstanding question of the contribution of large-orbit ions to the observed stability of experimental FRCs to the MHD tilt mode. Typical experimental FRCs with s {approx} 2-4, where s is the ratio of separatrix radius to ion gyro-radius, have been stable to tilting, but desired values for a fusion reactor, s > 20, should be unstable. The FIREX ring would consist of a plasma with large s for the background ions, but with s {approx} 1 for the ring ions. By varying the proportions of these two populations, the minimum proportion of large-orbit ions necessary for stability could be determined. The incorporation of large-orbit ions, perhaps by neutral-beam injection, into an FRC has been advanced for the purpose of stabilizing, heating, controlling angular momentum, and aiding the formation

  19. Three-dimensional simulations of ion dynamics in an Electron Cyclotron Resonance Ion Source

    NARCIS (Netherlands)

    Beijers, J. P. M.; Mironov, V.

    We present a three-dimensional simulation of the ion dynamics in an electron cyclotron resonance ion source. Ion trajectories in the min-B field of the source are calculated taking ion-ion and electron-ion collisions into account. The electrons are not tracked but considered as a neutralizing

  20. High Current Ion Sources and Injectors for Heavy Ion Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Kwan, Joe W.

    2005-02-15

    Heavy ion beam driven inertial fusion requires short ion beam pulses with high current and high brightness. Depending on the beam current and the number of beams in the driver system, the injector can use a large diameter surface ionization source or merge an array of small beamlets from a plasma source. In this paper, we review the scaling laws that govern the injector design and the various ion source options including the contact ionizer, the aluminosilicate source, the multicusp plasma source, and the MEVVA source.

  1. Data acquisition for the HILI [Heavy Ion Light Ion] detector

    International Nuclear Information System (INIS)

    Teh, K.M.; Shapira, D.; McConnell, J.W.; Kim, H.; Novotny, R.

    1987-01-01

    A large acceptance, multi-segmented detector system capable of the simultaneous detection of heavy and light ions has been constructed. The heavy ions are detected with a segmented gas ionization chamber and a multiwire proportional counter while the light ions are detected with a 192 element plastic phoswich hodoscope. Processing the large number of signals is accomplished through a combination of CAMAC and FASTBUS modules and preprocessors, and a Host minicomputer. Details of the data acquisition system and the reasons for adopting a dual standards system are discussed. In addition, a technique for processing signals from an individual hodoscope detector is presented. 4 refs., 3 figs

  2. Ion ring compressor as a high-current ion accelerator

    International Nuclear Information System (INIS)

    Fleischmann, H.H.

    1977-01-01

    The acceleration of large amounts of protons to several hundred MeV by adiabatic magnetic compression of low-energy ion rings are discussed. This method is to be used in the Ion Ring Compressor approach to thermonuclear fusion. Results from present experimental and theoretical investigations and estimates indicate good overall chances for a technical and economic feasibility of such a system. The method of acceleration might be used to generate efficiently the rather large amounts of several hundred MeV hydrogen ions that will be needed in any economically significant electronuclear breeding scheme

  3. Ion beam analysis of metal ion implanted surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Evans, P.J.; Chu, J.W.; Johnson, E.P.; Noorman, J.T. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Sood, D.K. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    Ion implantation is an established method for altering the surface properties of many materials. While a variety of analytical techniques are available for the characterisation of implanted surfaces, those based on particle accelerators such as Rutherford backscattering (RBS) and nuclear reaction analysis (NRA) provide some of the most useful and powerful for this purpose. Application of the latter techniques to metal ion implantation research at ANSTO will be described with particular reference to specific examples from recent studies. Where possible, the information obtained from ion beam analysis will be compared with that derived from other techniques such as Energy Dispersive X-ray (EDX) and Auger spectroscopies. 4 refs., 5 figs.

  4. Development of a microwave ion source for ion implantations

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, N., E-mail: Nbk-Takahashi@shi.co.jp; Murata, H.; Kitami, H.; Mitsubori, H.; Sakuraba, J.; Soga, T.; Aoki, Y.; Katoh, T. [Technology Research Center, Sumitomo Heavy Industries Ltd., Yokosuka, Kanagawa 237-8555 (Japan)

    2016-02-15

    A microwave ion source is expected to have a long lifetime, as it has fewer consumables. Thus, we are in the process of developing a microwave ion source for ion implantation applications. In this paper, we report on a newly developed plasma chamber and the extracted P{sup +} beam currents. The volume of the plasma chamber is optimized by varying the length of a boron nitride block installed within the chamber. The extracted P{sup +} beam current is more than 30 mA, at a 25 kV acceleration voltage, using PH{sub 3} gas.

  5. The Ion Funnel: Theory, Implementations, and Applications

    Science.gov (United States)

    Kelly, Ryan T.; Tolmachev, Aleksey V.; Page, Jason S.; Tang, Keqi; Smith, Richard D.

    2009-01-01

    The electrodynamic ion funnel has enabled the manipulation and focusing of ions in a pressure regime (0.1 to 30 Torr) that has challenged traditional approaches, providing the basis for much greater mass spectrometer ion transmission efficiencies. The initial ion funnel implementations aimed to efficiently capture ions in the expanding gas jet of an electrospray ionization source and radially focus them for efficient transfer through a conductance limiting orifice. We review the improvements in fundamental understanding of ion motion in ion funnels, the evolution in its implementations that have brought the ion funnel to its current state of refinement, as well as applications of the ion funnel for purposes such as ion trapping, ion cooling, low pressure electrospray, and ion mobility spectrometry. PMID:19391099

  6. Triplemafios: a multicharged heavy ion source

    International Nuclear Information System (INIS)

    Briand, P.; Geller, R.; Jacquot, B.

    1976-01-01

    The principle and the characteristics of the ion source 'Triplemafios' are described. We also furnish the upto date performances concerning the ion charge states, ion currents and globale emittances of the beam [fr

  7. Riesgos laborales en trabajadores del sector informal del Cauca, Colombia

    Directory of Open Access Journals (Sweden)

    Augusto Muñoz Caicedo

    2014-07-01

    Full Text Available Objetivo: describir los riesgos laborales de las personas ocupadas en el sector informal del comercio, en cinco municipios del departamento del Cauca, durante el año 2011. Métodos: estudio descriptivo, transversal, desarrollado con 223 sujetos a quienes se les aplicó una encuesta estandarizada a nivel nacional. Resultados: más del 20% de los taxistas y lecheros están expuestos a riesgos de seguridad, mientras que aproximadamente 1 de cada 4 de los vendedores ambulantes, carretilleros y vendedores de alimentos, están expuestos a riesgos ambientales. El grupo de mayor exposición a los riesgos sanitarios y a carga física son los carretilleros; más del 50% de estos, de vendedores de minutos y de vendedores ambulantes están expuestos a riesgos locativos. Además, aproximadamente 1 de cada 4 de los vendedores ambulantes y vendedores de alimentos están expuestos a riesgos de orden público. Discusión: Los riesgos laborales a los cuales están expuestos los trabajadores del sector informal del comercio, no coinciden con los encontrados por un estudio desarrollado a nivel nacional. Por otro lado, la poca organización dentro de los grupos de trabajadores y la falta de políticas públicas, pueden desencadenar aumento en la morbimortalidad de esta población.

  8. Análisis intraoperatorio del flujo del injerto coronario

    Directory of Open Access Journals (Sweden)

    Luis F. López Almodóvar

    2006-10-01

    Full Text Available El objetivo de la cirugía coronaria es volver a proporcionar riego sanguíneo al miocardio isquémico a fin de que el corazón pueda satisfacer las necesidades metabólicas del organismo. La oclusión intraoperatoria de injertos es una causa importante de morbimortalidad operatoria. Por este motivo, es de gran trascendencia confirmar la permeabilidad del injerto coronario durante la cirugía. El análisis del flujo del injerto coronario mediante la tecnología del tiempo de tránsito es un sistema que nos proporciona información, de forma rápida y sencilla, sobre si el injerto está permeable o no. El análisis de la onda, el flujo medio y los valores que derivan del mismo ayudan al cirujano a conocer si el injerto realizado está permeable o por el contrario existe algún error técnico que pudiera conducir a una oclusión precoz del mismo.

  9. Notas del Consejo Editorial

    Directory of Open Access Journals (Sweden)

    Fernando Serpa Florez

    1990-08-01

    Full Text Available

    Merecida Distinción
    Complacidos registrados la señalada distinción de que fue objeto en Hiroshima, Japón, durante la celebración del IX Congreso Mundial de la Organización Internacional a Médicos para la Prevención de la Guerra Nuclear (lPPNW el Académico Honorario Alberto Cárdenas Escovar quien recibió el Premio Albert Schweitzer, en reconocimiento a la meritoria labor que ha cumplido en el campo internacional de la medicina.

    Fernando Serpa Flórez

    Breves de la Academia
    En el número anterior de nuestra revista, por involuntaria omisión no se incluyeron dos señalados acontecimientos, que nos apresuramos a subsanar en la presente edición. Se trata del ingreso a la Corporación de dos distinguidos y muy apreciados Miembros de nuestro Instituto, el Académico correspondiente Joaquín Silva, Profesor de Cirugía y eminente maestro de numerosas generaciones médicas, quien disertó en forma erudita y ponderada sobre el tema “Los albores de la Medicina y Cirugía”. Así mismo tomó posesión como Miembro de Número el actual Presidente del Capítulo de los Santanderes de la Academia Nacional de Medicina, ex-decano de la Escuela de Medicina de la Universidad Industrial de Santander y notable escritor y psiquiátra doctor Roberto Serpa Flórez, quien presentó su libro sobre medicina y enfermedades tropicales en Colombia en la primera mitad de este siglo que, en forma interesante y amena, desarrolló alrededor de la biografía de su padre, el también Académico de Número profesor Roberto Serpa Novoa.

  10. Ion-ion interaction and energy transfer of 4+ transuranium ions in cerium tetrafluoride

    Energy Technology Data Exchange (ETDEWEB)

    Liu, G.K.; Beitz, J.V.

    1990-01-01

    Dynamics of excited 5f electron states of the transuranium ions Cm{sup 4+} and Bk{sup 4+} in CeF{sub 4} are compared. Based on time- and wavelength-resolved laser-induced fluorescence, excitation energy transfer processes have been probed. Depending on concentration and electronic energy level structure of the studied 4+ transuranium ion, the dominant energy transfer mechanisms were identified as cross relaxation, exciton-exciton annihilation, and trapping. Energy transfer rates derived from the fitting of the observed fluorescence decays to theoretical models, based on electric multipolar ion-ion interactions, are contrasted with prior studies of 4f states of 3+ lanthanide and 3d states of transition metal ions. 16 refs., 1 tab.

  11. Unlimited ion acceleration by radiation pressure.

    Science.gov (United States)

    Bulanov, S V; Echkina, E Yu; Esirkepov, T Zh; Inovenkov, I N; Kando, M; Pegoraro, F; Korn, G

    2010-04-02

    The energy of ions accelerated by an intense electromagnetic wave in the radiation pressure dominated regime can be greatly enhanced due to a transverse expansion of a thin target. The expansion decreases the number of accelerated ions in the irradiated region resulting in an increase in the ion energy and in the ion longitudinal velocity. In the relativistic limit, the ions become phase locked with respect to the electromagnetic wave resulting in unlimited ion energy gain.

  12. Del Charco del Agua Amarga (Alcañiz

    Directory of Open Access Journals (Sweden)

    Tomás MAIGI

    2009-10-01

    Full Text Available En agosto de 1947, habiendo llegado a la excelentísima Diputación Provincial de Teruel rumores de recientes deterioros en el friso pintado del abrigo rupestre del "Charco del Agua Amarga", nos fué requerida oficialmente, por dicha Corporación, la presentación de un informe sobre la realidad de los hechos expuestos, así como el planeamiento de las medidas adecuadas para salvaguardar en forma eficaz, en el futuro, las referidas pinturas.

  13. Calidad del servicio de taxis del municipio Maracaibo

    Directory of Open Access Journals (Sweden)

    Joheni A. Urdaneta G.

    2011-05-01

    Full Text Available El presente trabajo tiene como objetivo describir la calidad del servicio de los taxis en el municipio Maracaibo, ya que los mismos forman parte del sistema de transporte urbano de la ciudad, y es un servicio público fundamental para la convivencia de la sociedad; para lograr este objetivo se realizó una adaptación del modelo SERVPERF, diseñando un instrumento tipo cuestionario, con 32 ítems en 6 dimensiones, adecuado a las características propias del servicio de taxi, con la finalidad de confirmar que los ítems de los instrumentos se correspondían con las dimensiones adaptadas se aplicó la técnica de análisis factorial resultando un nuevo instrumento con 24 ítems en 3 dimensiones. Se utilizó la escala de Likert con tres (3 alternativas de respuesta. La investigación es de tipo descriptiva y aplicada, bajo diseño no experimental de tipo transeccional descriptiva y de campo. La población quedó conformada por los usuarios de las líneas de taxis del municipio Maracaibo. Se aplicó muestreo aleatorio por conglomerado. La confiabilidad del instrumento se midió a través del coeficiente alfa de Cronbach resultando de 0,82 lo cual se considera aceptable. Los resultados revelan que la calidad del servicio de taxis del municipio Maracaibo es mediana por lo tanto este servicio es susceptible a mejoras, las cuales son necesarias para elevar la calidad de vida de los marabinos. Este resultado se obtuvo con el instrumento originalmente adaptado de 32 ítems y con el cuestionario resultante del análisis factorial, de 24 ítems; esto confirma lo apropiado de esta técnica, ya que se redujo el número de ítems y de las dimensiones originalmente adaptadas y no se encontraron diferencias significativas en los resultados con ambos instrumentos; de esta manera se puede medir la calidad del servicio de taxis en el municipio Maracaibo a través de las dimensiones: confiabilidad del servicio, socialización y responsabilidad.

  14. Historia del desarrollo institucional turístico del Meta

    Directory of Open Access Journals (Sweden)

    Ramón Vergel

    2002-11-01

    el primer plan de desarrollo turístico departamental, se comienza a visualizar diferentes tipologías de turismo que se podían desarrollar como el Ecoturismo y a trabajar en pro de ello. Surge luego el segundo Plan Sectorial del Meta visualizando al turismo como producto. Posteriormente se realiza un Estudio Exploratorio sobre el Potencial Turístico del Meta y la promoción turística del departamento comienza a surgir con la participación en ferias y vitrinas turísticas importantes logrando así fijar un mercado turístico: Bogotá.

  15. Efectos del vendaje neuromuscular sobre la flexibilidad del raquis lumbar

    OpenAIRE

    A.M. Labrador-Cerrato; P. Ortega Sánchez-Diezma; G. Lanzas Melendo; C. Gutiérrez-Ortega

    2015-01-01

    Introducción: El vendaje neuromuscular es una técnica que produce una estimulación muy selectiva sobre la piel a través de la aplicación de unas vendas elásticas especiales con el fin de lograr cambios propioceptivos, aumento o inhibición del tono muscular y mitigación de algias, entre otros. Objetivos: Comprobar si la aplicación del vendaje neuromuscular permite aumentar la flexión del raquis lumbar comparándola con otras técnicas de vendaje placebo (esparadrapo rígido convencional; Omniplas...

  16. Materials research with ion beams

    International Nuclear Information System (INIS)

    Meyer, J.D.

    1988-01-01

    This report gives a series of helpful programs which are used in materials research with ion beams. In this context algorithms which can substitute table books are dealt with. This is true for the programs DEDX and PRAL; they are used in order to determine the energy loss of ions in solid bodies, their working range and straggling. Furthermore, simulator routines and analyzers are described. The program TRIM simulates the physical phenomena which occur with the penetration of high-energy ions into solid bodies. In this context electronic excitations, phonons and lattice distortions which are caused by the ions are dealt with. For the experimental ion implantation it is interesting to know the final distribution of the simulated ions in the solid body. The program RBS simulates the Rutherford spectrum of ions which are scattered from a solid body which may consist of up to nine elements and up to one hundred layers. The unknown composition of a solid body can be determined in direct comparison with the experimental spectrum. The program NRA determines concentration and penetrative distribution of an impurity by means of the experimental nuclear reaction spectrum of this impurity. All programs are written in FORTRAN 77. (orig./MM) [de

  17. Multi-source ion funnel

    Science.gov (United States)

    Tang, Keqi; Belov, Mikhail B.; Tolmachev, Aleksey V.; Udseth, Harold R.; Smith, Richard D.

    2005-12-27

    A method for introducing ions generated in a region of relatively high pressure into a region of relatively low pressure by providing at least two electrospray ion sources, providing at least two capillary inlets configured to direct ions generated by the electrospray sources into and through each of the capillary inlets, providing at least two sets of primary elements having apertures, each set of elements having a receiving end and an emitting end, the primary sets of elements configured to receive a ions from the capillary inlets at the receiving ends, and providing a secondary set of elements having apertures having a receiving end and an emitting end, the secondary set of elements configured to receive said ions from the emitting end of the primary sets of elements and emit said ions from said emitting end of the secondary set of elements. The method may further include the step of providing at least one jet disturber positioned within at least one of the sets of primary elements, providing a voltage, such as a dc voltage, in the jet disturber, thereby adjusting the transmission of ions through at least one of the sets of primary elements.

  18. Electrically switched cesium ion exchange

    International Nuclear Information System (INIS)

    Lilga, M.A.; Orth, R.J.; Sukamto, J.P.H.; Schwartz, D.T.; Haight, S.M.; Genders, J.D.

    1997-04-01

    Electrically Switched Ion Exchange (ESIX) is a separation technology being developed as an alternative to conventional ion exchange for removing radionuclides from high-level waste. The ESIX technology, which combines ion exchange and electrochemistry, is geared toward producing electroactive films that are highly selective, regenerable, and long lasting. During the process, ion uptake and elution are controlled directly by modulating the potential of an ion exchange film that has been electrochemically deposited onto a high surface area electrode. This method adds little sodium to the waste stream and minimizes the secondary wastes associated with traditional ion exchange techniques. Development of the ESIX process is well underway for cesium removal using ferrocyanides as the electroactive films. Films having selectivity for perrhenate (a pertechnetate surrogate) over nitrate also have been deposited and tested. A case study for the KE Basin on the Hanford Site was conducted based on the results of the development testing. Engineering design baseline parameters for film deposition, film regeneration, cesium loading, and cesium elution were used for developing a conceptual system. Order of magnitude cost estimates were developed to compare with conventional ion exchange. This case study demonstrated that KE Basin wastewater could be processed continuously with minimal secondary waste and reduced associated disposal costs, as well as lower capital and labor expenditures

  19. Propagation of light ion beam

    International Nuclear Information System (INIS)

    Okada, Toshio; Murakami, Hiroyuki; Niu, Keishiro.

    1983-01-01

    A method of rotating ion layer is proposed as a possible driver for inertial confinement fusion for the purpose of obtaining more stable ion beam against various micro- and macroinstabilities. The analysis was carried out within the frameworks of Vlasov and fluid models. A rotating ion layer propagating in the Z-direction is considered. The beam is described by a distribution function which satisfies the Vlasov equation. The equilibrium and microstability were studied. The filamentation instability is suppressed by a magnetic field due to the rotation of ion beam. To study the properties of the equilibrium state from the macroscopic standpoint, the equation of continuity of ion beam, the equation of motion and the Maxwell equations are considered. It is shown that the macroinstability is stabilized by the magnetic field in the Z-direction. It was found that the most dangerous instability for the problem of the propagation of ion beam was able to be atabilized by using a rotating ion layer. (Kato, T.)

  20. DIVALENT ION EXCHANGE WITH ALKALI

    Energy Technology Data Exchange (ETDEWEB)

    Bunge, A.L.; Klein, G.; Radke, C.J.

    1980-05-01

    Exchange of hardness ions is important in enhanced oil recovery with chemical additives. In both micellar-polymer and caustic flooding processes, multivalent ions released from rock surfaces can interact with anionic surfactants, rendering them preferentially oil soluble and/or insoluble in water. Because hardness cations are sparingly soluble and precipitate in alkaline solutions, such solutions may be more efficient as surfactant flood preflushes than are softened brines. Multivalent ion precipitation may also occur in alkaline waterflooding. To permit design of such processes, this paper presents a chromatographic theory for simultaneous ion exchange with precipitation of divalent ions. Theoretical effluent histories and concentration profiles are presented for the cases of finite pulses and continuous injection of hydroxide ions into linear cores. Complete capture of the insoluble salt particles is assumed. Results are given for the case of instantaneous equilibration of the solution with the precipitate, as well for the case of complete nonequilibrium, in which the solid precipitate does not redissolve. The efficiency of alklaine preflushing is shown to depend on the exchange isotherm, initial divalent loading of the rock, injected pH and salinity, the solubility product of the precipitated salt, and pulse size. The effect of slug size on complete equilibrium removal of hardness ions is reduced efficiency with increasing size until a critical volume approximating continuous injection is reached. Increasing injected pH and salinity provides a more favorable response. Experimental data for Berea sandstone and an argillaceous sand compare favorably with the proposed theory.

  1. Beneficios del descanso peritoneal

    Directory of Open Access Journals (Sweden)

    Jesús Lucas Martín Espejo

    Full Text Available Introducción: Valorar si el descanso peritoneal, de al menos un día semanal, ha supuesto mejoras en la rehabilitación de los pacientes y el impacto clínico que puede suponer. Nos planteamos además cuantificar el beneficio económico. Material y Método: Se realizó un estudio longitudinal, retrospectivo, descriptivo. De los pacientes atendidos en nuestra unidad desde el 1 de enero de 2014 al 31 de diciembre de 2014, se estudiaron los pacientes que cumplieran todo el año de seguimiento y que no procedieran de otras técnicas de depuración como la hemodiálisis o trasplante renal. La muestra de estudio estuvo compuesta por 40 pacientes, de los que 21 tuvieron prescrito al menos 1 día semanal de descanso peritoneal y 19 pacientes sin descanso. Se recogieron las siguientes variables al inicio del periodo de estudio y a los 12 meses: Variables demográficas, variables relacionadas con el estado de volumen, datos clínicos relacionados con la técnica, se pasó una encuesta de satisfacción a todos los pacientes estudiados, y se recogieron los importes del coste mensual de cada tipo de tratamiento. Resultados: Las diferencias iniciales entre los grupos, eran esperables ya que son los valores en los cuales se ha basado la prescripción del día de descanso. La exposición a la glucosa, al comienzo y al final fue menor en el grupo con descanso. Al año, no se encontró diferencias en los parámetros estudiados. Una encuesta de satisfacción nos reveló a que dedican los pacientes el día de descanso y los que no lo tienen a que lo dedicarían. Conclusiones: El descanso peritoneal no ha supuesto una peor evolución de los parámetros clínicos estudiados al año de seguimiento, cumpliendo las recomendaciones de adecuación de diálisis de las guías clínicas. La exposición a la glucosa, aun sin llegar a ser significativa por la duración del estudio, ha sido menor en el grupo con descanso. El día de descanso ha facilitado a los pacientes

  2. La materialidad del sonido

    Directory of Open Access Journals (Sweden)

    Esteban Manuel Stepanian Taracido

    2012-04-01

    Full Text Available La investigación sobre los procesos de producción sonora en la crea-ción de obras audiovisuales afectan, en términos generales, a cuestio-nes exclusivamente tecnológicas. Para valorar su rendimiento expresi-vo en la construcción del discurso es imprescindible que, de forma paralela, esta investigación se aborde también desde la perspectiva de la realización audiovisual.Para ello es necesario asumir que los conceptos básicos en los que se fundamenta el desarrollo tecnológico no han de ser necesariamente esenciales en los estudios que se plantean desde puntos de vista creati-vos.En particular es oportuno someter a examen el concepto de fidelidad y reivindicar las posibilidades emotivas, e incluso significantes, de formatos de producción sonora hoy en desuso.

  3. Repaso del Sabio Caldas

    Directory of Open Access Journals (Sweden)

    Jaime Paredes Pardo

    1983-01-01

    Full Text Available En Popayán aún se conserva la casa donde nació el sabio Francisco José de Caldas. Está situada en la esquina de la carrera 5a. con la calle 3a., en pleno barrio de la Pamba. Es una construcción robusta de líneas austeras y como especialidad única cuenta con un patio en cuyo centro se levanta un observatorio astronómico, obra del propio Caldas cuando estaba joven. Varios instrumentos que le fueron útiles fabricó para el observatorio, desde donde podía seguir el giro de los astros. Antes cuando era apenas un niño, su madre tenía que reprenderlo con alguna frecuencia porque tardaba demasiado en el estudio de los libros.

  4. cuarto del siglo XX

    Directory of Open Access Journals (Sweden)

    José Antonio Nieto Calmaestra

    2005-01-01

    Full Text Available Los últimos 25 años del siglo XX han supuesto un sustancial cambio en el modelo de crecimiento de la población andaluza. Así, mientras la caída de la fecundidad y la estabilización de las tasas de mortalidad han contribuido a un progresivo retroceso de la vitalidad natural, la masiva emigración de antaño ha dado paso al papel de Andalucía como incipiente foco de inmigración y al creciente protagonismo de movimientos internos de relocalización de la población. Desde el punto de vista territorial estas afirmaciones quedan matizadas por los notables contrastes que se producen entre los distintos ámbitos que conforman la región y que contraponen al medio rural con el urbano, al litoral con el interior o a las grandes ciudades con sus periferias.

  5. Memoria del mal

    Directory of Open Access Journals (Sweden)

    Semprún, Jorge

    2011-06-01

    Full Text Available In May 2003 the twelfth edition of the «Aranguren Conferences» was held. Jorge Semprún gave three keynote speeches titled «Kant and the Maquis’ rucksack», «The radical evil and the Buchenwald latrines» and «Literature and memory of the evil: from Sartre to Paul Ricoeur», all of them grouped under the generic denomination Memory of Evil. The thread running through the three speeches was Semprún’s experience as a political deportee at Buchenwald concentration camp, so close to the Weimar camp of Schiller and Goethe. There, he could experience the radical evil, but also the brotherhood through the antifascist resistance groups who coordinated the various clandestine political groups at the camp. This experience helped him review some of the philosophical readings he had done as a philosphy student at the Sorbonne, as well as those readings he took an interest in following the end of the war. In this way, Semprún went over various authors (Immanuel Kant, André Malraux, Edmund Husserl, Jacques Maritain, Martin Heidegger, Karl Marx, Hannah Arendt, Jean Paul Sartre, Paul Ricoeur or Primo Levi arguing their relationship with the issue of Evil.

    En mayo de 2003 se celebró la duodécima edición de las «Conferencias Aranguren». Jorge Semprún dictó tres conferencias magistrales tituladas «Kant y la mochila del maquis», «El mal radical y las letrinas de Buchenwald» y «Literatura y memoria del mal: de Sartre a Paul Ricoeur», agrupadas todas ellas bajo el título genérico de Memoria del mal. El hilo conductor de las tres intervenciones fue la experiencia de Semprún como deportado político en el campo de concentración de Buchenwald, tan cercano al Weimar de Schiller y Goethe. Allí pudo experimentar el mal radical, pero también la fraternidad, a través de los grupos de resistencia antifascista que coordinaban en el campo los distintos grupos políticos clandestinos. Esta experiencia le sirvió para repasar las lecturas

  6. Los presupuestos del Concurso

    Directory of Open Access Journals (Sweden)

    Línea de Investigación “De la Crisis Empresarial

    2006-01-01

    Full Text Available Este escrito es el resultado de uno de los proyectos de investigación adelantados por el Departamento de Derecho Comercial de la Universidad Externado de Colombia. En el se hace una aproximación histórica a los presupuestos para acceder a los trámites concursales en Perú, Argentina y España, analizándolos desde los puntos doctrinal, académico y legal.Así mismo, es parte integrante de un trabajo más amplio que pretende elaborar un documento contentivo del tratamiento que se da a los presupuestos concursales a nivel mundial.En este orden de ideas, nos permitimos presentar un análisis minucioso de la legislación de los citados países iberoamericanos.

  7. Carta del editor

    Directory of Open Access Journals (Sweden)

    Oscar Mauricio Covarrubias-Moreno

    2014-05-01

    Full Text Available Henos aquí con un nuevo número de RIESED. Después de casi un año de ver la luz, y como lo anticipábamos en la carta del editor que acompañaba al número fundacional, hacer una revista electrónica no ha sido una tarea sencilla. Un año más tarde no podemos sino confirmar esa opinión.Gracias al decidido trabajo de los autores, revisores y miembros del equipo editorial hemos podido hacerlo. El proceso de revisión de los artículos ha merecido un cuidado, dedicación y tiempo especiales, que hicieron necesario demorar unos días la fecha de publicación de este tercer número. Asumimos un compromiso con la calidad y estamos convencidos que esa es la única posibilidad de éxito para una revista científica. El contenido y nivel de los artículos disponibles servirá sin duda como incentivo para que los investigadores deseen publicar sus aportes en RIESED.Agradezco especialmente a la Dra. Gloria Rosique Cedillo, Editora Invitada y Coordinadora de este tercer número, así como al investigador César Nicandro Cruz-Rubio, Editor Asociado, apreciados colegas con quienes he tenido el privilegio de trabajar a lo largo de estos meses, y cuya dedicación y esmero han hecho posible RIESED 3.Por otra parte, derivado de nuestro proyecto editorial informo a ustedes de la creación de la Cátedra RIESED. Educación y Sociedad. Esta Cátedra es una iniciativa que la Universidad del Desarrollo Empresarial y Pedagógico ha impulsado en estrecha colaboración con el Grupo de Investigación en Gobierno Administración y Políticas Públicas (GIGAPP del Instituto Universitario de Investigación Ortega y Gasset (IUIOG, Fundación Ortega – Marañón; así como, con la Academia Internacional de Ciencias Político Administrativas y Estudios de Futuro A.C.La Cátedra está concebida como un espacio de diálogo y reflexión interdisciplinario sobre las diferentes temáticas abordadas en RIESED. En el marco de esta iniciativa académica, se invita a los miembros

  8. Avatares del paradigma conexionista

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    Asier Arias

    2012-02-01

    Full Text Available Hace ahora un año que falleciera David Everett Rumelhart, conexionista pionero y editor junto con James Lloyd McClelland de la llamada “biblia del Procesamiento Distribuido en Paralelo” (PDP. Al mismo tiempo, los dos volúmenes de la referida biblia celebraban su vigésimo quinto cumpleaños. También uno de los padres de la inteligencia artificial, John McCarthy, que bautizara de hecho la disciplina, nos abandonó el pasado mes de octubre a los 84 años. Estas tres efemérides nos sirven de pretexto para un breve recorrido por las derivas y obstáculos a los que se ha enfrentado el llamado paradigma conexionista desde su puesta en escena como alternativa al cognitivismo clásico.

  9. El reordenamiento del mundo

    Directory of Open Access Journals (Sweden)

    Antonio Pasquali

    2015-01-01

    Full Text Available Se publica la propuesta de marco histórico y proyección de futuro de Antonio Pasquiali, en nuestra opinión, es útil referente contextualizado para los ensayos y estudios de caso sobre la formación del comunicador profesional. La evolución reciente de la filosofía, la ciencia y la tecnología llevan a Pasquali a afirmar que la humanidad se encamina lentamente hacia la reformulación global de la moral de la intersubjetividad, y a replantear desde sus cimientos el contrato social que concierne a la comunicación social mediática.

  10. La democracia del futuro

    Directory of Open Access Journals (Sweden)

    Rodrigo Borja

    2015-01-01

    Full Text Available El desarrollo logrado por la informática, la microelectrónica y en general las nuevas tecnologías de la información, hace que del zoon politikon aristotélico se pase al homo digitalis posmoderno, de una "democracia restringida" a una telecracia: en el siglo XXI. El autor vaticina que el voto se hará vía computadores desde casa a través de éstos, los gobernantes podrán tener una relación directa con los gobernados, las consultas populares serán más frecuentes, las implicaciones para los regímenes democráticos serán enormes y es en torno a ellas que reflexiona el autor

  11. APOLOGIA DEL REPUBLICANISMO DEMOCRATICO

    OpenAIRE

    Rivera García, Antonio

    2015-01-01

    Este libro nos presenta al republicanismo democrático como la mejor concepción política de nuestros días. El autor asume la tarea de conciliar la filosofía política republicana, la centrada en la libertad, con la teoría política de la democracia basada en el gobierno de los muchos pobres libres. Nos parece que este republicanismo está unido a una nueva definición del Estado de bienestar, empresa que pasa por evitar sus defectos mediante dos fórmulas: la extensión de la virtud republicana y el...

  12. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available La publicación aborda los siguientes temas: La ley de comunicación en Venezuela y México, La libertad de prensa, el fenómeno Berlusconi en Italia, la cooperación internacional respecto a la utilización de los medios de comunicación en los países en desarrollo, los procesos educativos en favor de los indios Mapuches en Chile, la exaltación de la violencia en la televisión, el papel del ombudsman, la transformación de las relaciones públicas en la llamada Comunicación estratégica y finalmente la Radio digital.

  13. Condromatosis sinovial del hombro

    Directory of Open Access Journals (Sweden)

    Luis Mancilla Mancilla

    2007-07-01

    Full Text Available La osteocondromatosis sinovial es una metaplasia idiopática benigna de la membrana sinovial. Las manifestaciones están en relación con los cuerpos libres intra-articulares y la excesiva actividad física, las que pueden hacer que esta condición sea sintomática y potencialmente ser causa de artropatía degenerativa. Un varón de 32 años refirió dolor periódico del hombro izquierdo, en la radiografía se encontró el signo de "la tormenta de nieve", fue tratado con cirugía y la anatomía patológica mostró osteocondromatosis sinovial. (Rev Med Hered 2007;18:161-164.

  14. Medida del gasto cardiaco

    OpenAIRE

    Cortes A., Carlos Albertos; Florez H., Ruben Dario

    2018-01-01

    Uno de los campos más amplios y poco explotados en nuestro medio para realizar investigación aplicada, es el de la Ingeniería Biomédica. En él se pueden enfocar los esfuerzos en la adquisición, tratamiento y análisis de biopotenciales (señales biológicas), al igual que en el diseño, construcción y puesta a punto de equipos y sistemas Software/Hardware de uso específico en Medicina.El presente trabajo MEDIDA DEL GASTO CARDIACO es buen ejemplo de ello. Con pocos recursos, y gran dedtcactón , lo...

  15. Especiación de tierras raras en las soluciones ácidas y neutras del sistema de drenaje del Arroyo del Val (Zaragoza

    Directory of Open Access Journals (Sweden)

    Zamora, A.

    1994-08-01

    Full Text Available Special geochemical characters of the Arroyo del Val drainage basin allow to study different aspects related to REE behaviour. The hydrologic system contains a main stream (Arroyo del Val of acidic waters naturally generated (sulfate rich solutions, with high levels of Al, Fe and heavy metals, and with pH values between 3 and 4.5 and several calcium bicarbonate (sulfate tributaries (with pH values as high as 7.5, measurable alkalinity and striking phosphate concentrations. Mixing of the acidic stream with neutral tributaries yields spectacular sulfate-iron-aluminum rich flocculants that precipitate at the confluences, along the principal stream. The concentration of REEs was measured for acidic water samples col1ected along the headwaters zone of the Arroyo del Val stream and for neutral water samples fram two tributaries. The REE content of acidic waters are enriched by 102 relative to neutral ones and the shale-normalized REE patterns for these acidic freshwaters are enriched in the inter• mediate REEs (IREE, Eu-Tb. Speciation calculations were performed on both water groups. Dominant forms of REEs in the acidic waters include free metal species (Ln3+ ≈ 35% and mainly sulfate complexes ((LnSO+4 ≈ 60% and minor Ln(SO4-2 ≈ 5%. REE sulfate complexation don't fractionate the REEs in solution because there is not an appreciable variation in REE sulfate complexation constants across the lanthanide serie. So, REE convex patterns in these acidic waters must be related to interaction of the acid waters with clay minerals and oxyhydroxide coatings in the paleozoic materials of drainage basin and/or with the col1oid pool of those waters. In the neutral freshwaters of tributaries dissolved REEs are complexed with carbonate and phosphate ions. REE carbonate and phosphate complexation constants across the lanthanide serie increase by several orders of magnitude from La to Lu. And so, phosphate and carbonate complexes account for 80

  16. Para aprender del pasado

    Directory of Open Access Journals (Sweden)

    Esquivel Valverde, Lidier

    2004-05-01

    Full Text Available Este texto reflexiona sobre la importancia de reconocer el valor que tiene el conocimiento de los eventos del pasado, como fuentes importantes de lecciones aprendidas. Inicia presentando ejemplos de sucesos históricos en Japón y cómo estos han sido utilizados de forma positiva en los procesos de educación en niños y adultos. Posteriormente presenta la realidad de Costa Rica, donde a nivel de la población existe un desconocimiento de hechos históricos sobre el tema, al propiciarse su olvido u ocultamiento. Finalmente, los autores exponen sobre un programa del Área de Prevención de la Comisión Nacional de Prevención de Riesgos y Atención de Emergencias, quienes se han dedicado de distribuir reseñas históricas breves de los principales eventos en el país This text reflects about the importance of recognizing the value of knowing past events as important sources for lessons learned. It starts including examples of historical events in Japan and how they have been used positively in the educational processes for children and adults. Lately, it includes the reality in Costa Rica. The population does not know about historical events on the topic because they have been forgotten or not shared. Finally, the authors refer to a program of the Prevention Area of the National Commission of Risk Prevention and Emergency Response that has dedicated to distribute brief historical reviews about the main events in the country

  17. Carta del editor

    Directory of Open Access Journals (Sweden)

    Simón Espinosa

    2015-01-01

    Full Text Available La autora relata la historia de las Relaciones Públicas y dice que surgieron y se desarrollaron para legitimar ante el público los intereses económicos y políticos de quienes detentan el poder. Se cuestiona sobre el por qué no aplicar las relaciones públicas, en organizaciones populares, para que mejoren su publicación y orienten sus propósitos de desarrollo. El tema que aborda las Políticas culturales en América Latina acopia un extracto de lo más trascendente de los ensayos del libro editado por Néstor García Canclini. Sobre la telenovela se afirma que esta ha llegado a ser uno de los instrumentos más importantes de la comunicación popular: por ella desfilan las identidades de las más variadas culturas brasileñas. Y en cuanto a la caricatura se relata lo que ocurrió en el Seminario taller " Caricatura y Periodismo", realizado el(9-11 de Nov.- 1987 en el CIESPAL. El estudio sobre el mercado del vídeo se ve dificultado por la imprecisión de los datos obtenidos. Los datos oficiales no siempre se aproximan a la realidad, pues el mercado de vídeo se instauró en América Latina partiendo de una lógica totalmente diversa de los equipos de sonido e imagen.

  18. Discurso del Presidente Entrante

    Directory of Open Access Journals (Sweden)

    Gilberto Rueda Pérez

    1994-09-01

    Full Text Available

    Santafé de Bogotá, D.C., 17 de mayo de 1994

    Señoras y señores:

    Estoy profundamente conmovido y emocionado, al escuchar los elogiosos comentarios de quienes me precedieron en el uso de la palabra, pues, aunque inmerecidos, naturalmente me enorgullecen sobremanera.

    Quiero, antes de iniciar mi discurso, agradecer a la noble Academia de la Lengua, a su presidente doctor Jaime Posada y a los miembros de su Junta Directiva, la generosa hospitalidad en este precioso auditorio que contribuye a dar realce a esta sesión solemne.

    Muchas Gracias.

    Deseo manifestar, que los conceptos que vaya emitir, reflejan mi pensamiento y por tanto, de ellos soy responsable. No pretendo con ellos criticar, ni mucho menos ofender, a personas o instituciones, son más que todo reflexiones, que me llevan a propuestas de trabajo para el futuro y espero que así sean percibidas y analizadas por esta distinguida audiencia.

    El día 3 de enero de 1873, el joven médico Abraham Aparicio, reunió en su residencia, en las primeras horas de la fría noche santafereña, a sus colegas Manuel Plata Azuero, Nicolás Osario, Liborio Zerda, Leoncio Barreta y Evaristo García, con el propósito de crear una sociedad científica, para el estudio y adelanto de las ciencias médicas y naturales, así como para solidarizar al cuerpo médico y darle unidad al ejercicio profesional en el país. Así nació la Sociedad de Medicina y Ciencias Naturales que posteriormente sería elevada a la categoría de Academia Nacional de Medicina, por la Ley 71 de 22 de noviembre de 1890.

    Sin embargo, bien vale la pena rememorar los orígenes aún más remotos, de esta insigne institución.

    El 29 de diciembre de 1816, el Dr. Pablo Fernández de la Reguera, médico cirujano, químico y boticario mayor del ejército expedicionario, inspector de los hospitales, en comunicación dirigida al Sr. Brigadier Don Juan Sámano, Gobernador militar y político de la

  19. Valor social del anciano

    Directory of Open Access Journals (Sweden)

    Luna Torres Bertha

    1997-11-01

    Full Text Available

    The old age is been surrounded bymisteries, myths and prejuidices. The concepts and the valoration of the ancient man, have been contradictory. In different places and in many cultural moments, the old man has been taken from the glory to the scorn. The actual world scrolls the ancient in a very fast rhythm; the social changes have generayed conditions of disadvantajes for that group of the population, difficulting even more the process of growing old, that in fact has a lot of limitations. Its important that a lot of professionals from many institutions involved with this important cause, join the work developed by geriatrics and gerontologics;  soin this way we can restore the social values of the ancient, who deserves a peacefull old age in compensation with his participation in the job of building a better society. Only in this way, the fear to grow old will be lost.

    La vejez se ha visto rodeada de tabúes, mitos y prejuicios. Han sido contradictorios los conceptos y la valoración del anciano, quien en lugares y momentos culturales ha estado desde ensalzado hasta despreciado. El mundo actual, desplaza al geronte a ritmo acelerado; los cambios sociales han generado condiciones de marginalidad para ese sector de población, dificultando aun más el proceso de envejecer, que de hecho tiene limitaciones. Es por eso importante que al trabajo que desarrollan geriatras y gerontólogos se sumen otros profesionales y un sinnúmero de entidades; en aras de eliminar prejuicios y rescatar el valor social del anciano, quien por su legado merece un ocaso, que compense su aporte y participación en la construcción de la sociedad, solo así se perderá el miedo a envejecer.

     

  20. Sentido del flexnerismo

    Directory of Open Access Journals (Sweden)

    José Félix Patiño Restrepo

    1995-04-01

    Full Text Available Según Flexner, la medicina es básicamente un sistema educativo; y esta es la esencia de su mensaje. Planteó que el médico ideal, ante todo, debe ser una persona educada, alguien en quien se unan en forma indisoluble la ciencia, el humanismo y la responsabilidad social. Las premisas flexnerianas, que expresan su amplia concepción científica y social de la medicina, son de especial pertinencia en el análisis contemporáneo de la educación médica. Las ciencias fundamentales (química, biología, física proveen la instrumentación básica de la educación médica. Pero una instrumentación mínima no puede servir como el mínimo del profesionalismo. El progreso científico ha modificado grandemente la responsabilidad ética de la medicina. La relación de la medicina fue con el paciente, y hasta con la familia, y casi exclusivamente de carácter remedial. Pero la función del médico rápidamente se ha convertido en una de carácter social y preventivo. La sociedad confía en el médico para determinar las condiciones que le permitan prevenir la enfermedad y promover el bienestar físico y moral.

  1. Carta del Editor

    Directory of Open Access Journals (Sweden)

    Blasco Fernando Checa Montúfar

    2015-01-01

    Full Text Available En "El laberinto de la ciberred" se habla de los beneficios y problemas que caracteriza el caos existente en la telaraña cibernética. Ahora el cibernauta puede acceder a una inimaginable oferta de información multimedia. Este caos garantiza libertades, pero presenta enormes limitaciones para quienes no tienen acceso a la tecnología, particularmente en países de América Latina, carentes de Políticas de Comunicación que generen condiciones para un uso intensivo, extensivo y democrático de la ciberred. En el tema “La televisión por cable" relacionado con la cultura visual, multimediática, satelital, informática, televisionada, se señala que tiene como soporte a la más antigua nueva tecnología, la televisión por cable. Se trata de uno de los más grandes negocios disputados por los magnates nacionales y transnacionales de la comunicación que atraparon para el año 2000 a más de 20 millones de suscriptores de la televisión pagada. En esta entrega se presentan distintos acercamientos del perfil del ombudsman de prensa, las ventajas y límites de esta institución, su necesaria independencia, trasfondo ético, autonomía y otros aspectos que contribuirán a fortalecer mecanismos adecuados para controlar este "peligroso poder”

  2. Anafilaxis, estado del arte

    Directory of Open Access Journals (Sweden)

    Eduardo E. Egea

    2004-01-01

    Full Text Available La anafilaxis se puede definir como un síndrome constituido por una variedad de síntomas, que usualmente atentan contra la vida y que puede ser causado por varios mecanismos, los cuales son generalmente de índole inmunológico. Las reacciones causadas por mecanismos no inmunológicos que desencadenan los mismos fenómenos fisiopatológicos se denominan reacciones anafilactoideas. Las manifestaciones clínicas pueden aparecer entre 5 y 30 minutos después de la exposición al agente causal, sin embargo, existen pacientes en los que los signos y síntomas se manifiestan hasta horas después. Todos los eventos moleculares que ocurran se traducen en daño a órganos blancos. Los órganos más afectados durante una reacción anafiláctica varían entre especies. En el ser humano, el corazón y el pulmón son los más afectados. Cualquier agente es capaz de activar y producir degranulación de mastocitos y basófilos para culminar en una crisis anafiláctica o anafilactoidea, almenos potencialmente. Para lograr un adecuado tratamiento de una crisis anafiláctica, debemos comprender que no todos los casos se presentan de una misma manera. El progreso puede ser muy veloz y severo en un paciente. Adrenalina es el medicamento de elección. Mantener las vías aéreas expeditas y garantizar una homeostasis del sistema cardiovascular son los objetivos del tratamiento farmacológico.

  3. Laser induced fluorescence of trapped molecular ions

    Energy Technology Data Exchange (ETDEWEB)

    Grieman, F.J.

    1979-10-01

    An experimental apparatus for obtaining the optical spectra of molecular ions is described. The experimental technique includes the use of three dimensional ion trapping, laser induced fluorescence, and gated photon counting methods. The ions, which are produced by electron impact, are confined in a radio-frequency quadrupole ion trap of cylindrical design. Because the quadrupole ion trap allows mass selection of the molecular ion desired for study, the analysis of the spectra obtained is greatly simplified. The ion trap also confines the ions to a region easily probed by a laser beam. 18 references.

  4. Laser induced fluorescence of trapped molecular ions

    International Nuclear Information System (INIS)

    Grieman, F.J.

    1979-10-01

    An experimental apparatus for obtaining the optical spectra of molecular ions is described. The experimental technique includes the use of three dimensional ion trapping, laser induced fluorescence, and gated photon counting methods. The ions, which are produced by electron impact, are confined in a radio-frequency quadrupole ion trap of cylindrical design. Because the quadrupole ion trap allows mass selection of the molecular ion desired for study, the analysis of the spectra obtained is greatly simplified. The ion trap also confines the ions to a region easily probed by a laser beam. 18 references

  5. Heavy ion elastic scatterings

    International Nuclear Information System (INIS)

    Mermaz, M.C.

    1984-01-01

    Diffraction and refraction play an important role in particle elastic scattering. The optical model treats correctly and simultaneously both phenomena but without disentangling them. Semi-classical discussions in terms of trajectories emphasize the refractive aspect due to the real part of the optical potential. The separation due to to R.C. Fuller of the quantal cross section into two components coming from opposite side of the target nucleus allows to understand better the refractive phenomenon and the origin of the observed oscillations in the elastic scattering angular distributions. We shall see that the real part of the potential is responsible of a Coulomb and a nuclear rainbow which allows to determine better the nuclear potential in the interior region near the nuclear surface since the volume absorption eliminates any effect of the real part of the potential for the internal partial scattering waves. Resonance phenomena seen in heavy ion scattering will be discussed in terms of optical model potential and Regge pole analysis. Compound nucleus resonances or quasi-molecular states can be indeed the more correct and fundamental alternative

  6. Ultrarelativistic heavy ions

    International Nuclear Information System (INIS)

    Pugh, H.G.

    1980-12-01

    Studies with ultrarelativistic heavy ions combine aspects of cosmic ray physics, particle physics, nuclear physics, astrophysics and cosmogenesis. The leading theoretical concerns are the behavior of matter at very high-energy density and flux, the general behavior of space time in collisions, relativistic nuclear theory, and quantum chromodynamics. The field has developed over a period of more than thirty years, since the first observation of heavy nuclei in cosmic rays and the major developments of understanding of high-energy collisions made by Fermi and Landau in the early fifties. In the late sixties the discovery of the parton content of nucleons was rapidly followed by a great extension of high-energy collision phenomenology at the CERN ISR and subsequent confirmation of the QCD theory. In parallel the study of p-nucleus and nucleus-nucleus collisions at very high energies, especially at the CERN PS, Fermilab and the Bevalac, and in cosmic rays demonstrated that studies involving the nucleus opened up a new dimension in studies of the hadronic interaction. It is now at a high level of interest on an international scale, with major new accelerators being proposed to dedicate to this kind of study

  7. Heavy ion activation analysis

    International Nuclear Information System (INIS)

    Lass, B.D.; Roche, N.G.; Sanni, A.O.; Schweikert, E.A.; Ojo, J.F.

    1982-01-01

    A report on radioactivation with ion beams of 3 6 Li and 14 N is presented with some analytical applications: the determination of C via 12 C( 6 Li,αn) 13 N; the determination of Li and Be, using 14 N activation. Next, examples, with limitations in selectivity. The detection limits using a 1 μA h of activation irradiation are 5 ppm for C and 1 ppm for Li or Be. With 9 Be suitable for analytical applications are: sup(10,11)B( 9 Be,xn) 18 F and 14 N( 9 Be,αn) 18 F. Assuming a 1 μA h irradiation the detection limits for N and B are 1.5 ng and 0.5 ng, respectively, using a 7.8 MeV 9 Be beam. For activation with 12 C, experimental results with 12 MeV 12 C beam demonstrate that the beam is best suited for 7 Li analysis by the reaction 7 Li( 12 C,n) 18 F. The detection limit for a 1 μA h irradiation is 1 ng and the only other low Z elements activated are B and C. Finally, 12 C radioactivation was further combined with autoradiography for positional analysis. The spatial resolution of the technique was estimated to be 40 μm for an exposure corresponding to 6x10 5 disintegrations. As low as 10 -12 g of Li was readily detected by autoradiography. (author)

  8. Relativistic heavy ion research

    International Nuclear Information System (INIS)

    1992-01-01

    Experimental work is reported on the following topics: transverse energy production in 10.7-GeV/c/u Au on Au collisions; first results on delta ray production and charged particle multiplicities with the Au beam at 10.7 GeV/c/A; preliminary studies on the feasibility of flow measurement with the E814 participant calorimeter; preliminary results from the E877 telescope; and low-p t baryon distribution in Si+Al, Pb collisions at the AGS. Then the status of the Hadronic Calorimeter project of AGS Experiment E864 (ECOS--Exotic Composite Object Spectrometer) is reviewed. Next, the same is done for work of the STAR RHIC collaboration (Silicon Vertex Tracker (SVT) project evolution and development in FY92, SVT software results from 1992, SVT instrumentation, FY93 SVT pion test beam). The instrumentation section deals with the design and installation of a target rapidity telescope for BNL experiment 814/877 and a repair scheme for the E814/E877 participant calorimeter. Finally, the theory part addresses bosonic kinetics: thermalization of mesons and the pion p perpendicular spectrum in ultrarelativistic heavy-ion collisions and non-equilibrium properties of hadronic mixtures

  9. LHC Report: Ion Age

    CERN Multimedia

    John Jowett for the LHC team

    2013-01-01

    The LHC starts the New Year facing a new challenge: proton-lead collisions in the last month before the shutdown in mid-February.    Commissioning this new and almost unprecedented mode of collider operation is a major challenge both for the LHC and its injector chain. Moreover, it has to be done very quickly to achieve a whole series of physics goals, requiring modifications of the LHC configuration, in a very short time. These include a switch of the beam directions halfway through the run, polarity reversals of the ALICE spectrometer magnet and Van der Meer scans.    The Linac3 team kept the lead source running throughout the end-of-year technical stop, and recovery of the accelerator complex was very quick. New proton and lead beams were soon ready, with a bunch filling pattern that ensures they will eventually match up in the LHC. The LEIR machine has even attained a new ion beam intensity record.  On Friday 11 January the first single bunches o...

  10. Los objetivos del desarrollo

    Directory of Open Access Journals (Sweden)

    Currie Lauchlin

    1993-12-01

    Full Text Available To broach the goals of development implies broaching the problem of economic growth in a critical manner. Not only the concept of growth but also the means of achieving it in practice should be questioned. Growth is not an end, it is a means of gaining access to development And development should not be understood as a goal, but as a permanent process of learning tending towards more control over the environment and greater levels of well-being. It is not a matter of increasing GNP linearly; development must occur, sustained growth that, without being a threat to mm or to our natural resources, can lead to the eradication of absolute and relati.ve poverty. The low rates of growth of the developing countries constitute structural problem that can /lot be reso1.ved by resorting to the neo-classical mechanisms of mobility, nor to the Keynesian formulas. These have served as a source of inspiration to the Harrod-lX:m3r·type models of growth which limit themselves to stimulating savings and ending unemployment by concentrating exclusively on the monetary demand. Getting OUt of the vicious circle of low growth implies eradicating poverty with respect into the immediateness of a direct attack on the problem. with respect to the developed counties, growth is starting to became harmful, and, given the prevalence of ostensible consumption and of pecuniary emulation, it is imperative to foment non-economic motivation that will permit the eradication of relative poverty.

    Abordar los objetivos del desarrollo implica abordar de manera crítica el problema del crecimiento econ

  11. Deslumbramientos del mercado

    Directory of Open Access Journals (Sweden)

    Monique Selim

    2006-07-01

    Full Text Available Con eje en los diferentes aspectos que adopta el actual proceso de mundialización de la lógica del mercado y expansión capitalista, aún en países socialistas, el presente artículo plantea la necesidad de una reflexión antropológica susceptible de articular el surgimiento de nuevas formas de dominación y representación simbólicas. Se discute el aparente efecto de unificación intelectual producido por la hegemonía del mercado respecto de hechos sociales heterogéneos dados en la historia reciente de las sociedades contemporáneas. Así, la renovada atracción que ejercen los nuevos escenarios sociales reconfigurados en virtud de las modalidades específicas de encarnación y operación de los procesos globalizantes, llama al estudio antropológico de las coyunturas. La autora despliega una interpretación del socialismo de mercado, conjunción -siempre en tensión- de un monopolio político estatal y una liberalización del mercado económico. En esta perspectiva se reubica el interés de una antropología del presente en relevar localmente, en este caso en Vietnam del Norte, la conformación de un nuevo mercado de demandas simbólicas, donde la reaparición de las prácticas culturales de comunicación con los antepasados expresa la necesidad de reunificación familiar y reconciliación con los muertos en la "larga guerra".Tendo como eixo os aspectos diferentes que adota o processo atual de mundialização da lógica do mercado e de expansão capitalista, até mesmo nos países socialistas, este artigo propoe a necessidade de uma reflexão antropológica capaz de articular o aparecimento de novas formas de dominação e de representação simbólica. Discute-se o efeito de superfície de unificação intelectual causado pela hegemonia do mercado em fatos sociais diversos em sociedades contemporâneas. Assim, a atração renovada de novos fatos sociais pelos modos específicos de incorporação e operação de processos de globaliza

  12. Plasma ion sources and ion beam technology inmicrofabrications

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Lili [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    For over decades, focused ion beam (FIB) has been playing a very important role in microscale technology and research, among which, semiconductor microfabrication is one of its biggest application area. As the dimensions of IC devices are scaled down, it has shown the need for new ion beam tools and new approaches to the fabrication of small-scale devices. In the meanwhile, nanotechnology has also deeply involved in material science research and bioresearch in recent years. The conventional FIB systems which utilize liquid gallium ion sources to achieve nanometer scale resolution can no longer meet the various requirements raised from such a wide application area such as low contamination, high throughput and so on. The drive towards controlling materials properties at nanometer length scales relies on the availability of efficient tools. In this thesis, three novel ion beam tools have been developed and investigated as the alternatives for the conventional FIB systems in some particular applications. An integrated focused ion beam (FIB) and scanning electron microscope (SEM) system has been developed for direct doping or surface modification. This new instrument employs a mini-RF driven plasma source to generate focused ion beam with various ion species, a FEI two-lens electron (2LE) column for SEM imaging, and a five-axis manipulator system for sample positioning. An all-electrostatic two-lens column has been designed to focus the ion beam extracted from the source. Based on the Munro ion optics simulation, beam spot sizes as small as 100 nm can be achieved at beam energies between 5 to 35 keV if a 5 μm-diameter extraction aperture is used. Smaller beam spot sizes can be obtained with smaller apertures at sacrifice of some beam current. The FEI 2LE column, which utilizes Schottky emission, electrostatic focusing optics, and stacked-disk column construction, can provide high-resolution (as small as 20 nm) imaging capability, with fairly long working distance (25

  13. Plasma ion sources and ion beam technology in microfabrications

    International Nuclear Information System (INIS)

    Ji, Lili

    2007-01-01

    For over decades, focused ion beam (FIB) has been playing a very important role in microscale technology and research, among which, semiconductor microfabrication is one of its biggest application area. As the dimensions of IC devices are scaled down, it has shown the need for new ion beam tools and new approaches to the fabrication of small-scale devices. In the meanwhile, nanotechnology has also deeply involved in material science research and bioresearch in recent years. The conventional FIB systems which utilize liquid gallium ion sources to achieve nanometer scale resolution can no longer meet the various requirements raised from such a wide application area such as low contamination, high throughput and so on. The drive towards controlling materials properties at nanometer length scales relies on the availability of efficient tools. In this thesis, three novel ion beam tools have been developed and investigated as the alternatives for the conventional FIB systems in some particular applications. An integrated focused ion beam (FIB) and scanning electron microscope (SEM) system has been developed for direct doping or surface modification. This new instrument employs a mini-RF driven plasma source to generate focused ion beam with various ion species, a FEI two-lens electron (2LE) column for SEM imaging, and a five-axis manipulator system for sample positioning. An all-electrostatic two-lens column has been designed to focus the ion beam extracted from the source. Based on the Munro ion optics simulation, beam spot sizes as small as 100 nm can be achieved at beam energies between 5 to 35 keV if a 5 (micro)m-diameter extraction aperture is used. Smaller beam spot sizes can be obtained with smaller apertures at sacrifice of some beam current. The FEI 2LE column, which utilizes Schottky emission, electrostatic focusing optics, and stacked-disk column construction, can provide high-resolution (as small as 20 nm) imaging capability, with fairly long working distance

  14. The ions displacement through glasses

    International Nuclear Information System (INIS)

    Sevegnani, F.X.

    1980-01-01

    A method to introduce sodium, potassium, lithium, calcium, iron and other ions in vacuum or gas light bulb by mean of a strong stationay electric field. The experiments showed that the mass deposited inside the bulbs obey Faraday's law of electrolysis, although the process of mass transfer is not that of a conventional electrolysis. A method which allows to show that hydrogen ions do not penetrate the glass structure is also described. Using radioactive tracers, it is shown that heavy ions, such PO 4 --- do not penetrate the glass structure. The vitreous state and the glass properties were studied for interpreting experimental results. (Author) [pt

  15. Intense beams of light ions

    International Nuclear Information System (INIS)

    Camarcat, Noel

    1985-01-01

    Results of experiments performed in order to accelerate intense beams of light and heavier ions are presented. The accelerating diodes are driven by existing pulsed power generators. Optimization of the generator structure is described in chapter I. Nuclear diagnostics of the accelerated light ion beams are presented in chapter II. Chapter III deals with the physics of intense charged particle beams. The models developed are applied to the calculation of the performances of the ion diodes described in the previous chapters. Chapter IV reports preliminary results on a multiply ionized carbon source driven by a 0.1 TW pulsed power generator. (author) [fr

  16. Prospects for ion beam fusion

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R.L.

    1977-01-01

    The promise of pellet fusion by high energy heavy ions has evolved very rapidly, partly because of prior pellet work in the laser and e beam programs and partly because of an inherently good match to the application. ERDA sponsored a summer study in 1976 which has had a significant impact on the direction the ion beam fusion program has evolved. Experimental R and D work has been initiated in three of the U.S. accelerator laboratories. Argonne's development program is described. This development work, if successful, should lead to a great deal of confidence that the concept of pellet fusion by high energy heavy ions is indeed practical.

  17. Review of superconducting ion linacs

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1992-01-01

    This paper summarizes the status of the technology of superconducting (SC) linacs designed for the acceleration of ions. The emphasis is on the technical issues involved, with only brief descriptions of the numerous linacs now in operation or under construction. Recent developments of special interest are treated in more detail, and remaining technical challenges are outlined. The technology required for the acceleration of ions with velocity β=1 is not discussed because it is almost the same as for relativistic electrons. That is, this paper is mainly about SC linacs for low-velocity heavy ions

  18. Ion content of synaptic vesicles

    International Nuclear Information System (INIS)

    Demeter, I.; Keszthelyi, L.; Szokefalvi-Nagy, Z.; Varga, L.; Hollos-Nagy, K.; Nagy, A.

    1977-09-01

    Proton induced X-ray emission analysis measurements were performed to determine the P, S, K, Ca, Fe, Ni, Cu, and Zn ion content of presynaptic vesicles prepared from guinea-pig cortex brain. The number of different ions per single vesicle is calculated using results of the additional protein content determinations. The ion content of cholinergic and adrenergic vesicles are compared. Some rough conclusions can be made regarding the biochemistry of vesicles on the basis of this measurements, but the elucidation of the meaning of the data needs further work which will demonstrate the value of PIXE-type investigations in similar studies. (D.P.)

  19. Amorphization of metals by ion implantation and ion beam mixing

    International Nuclear Information System (INIS)

    Rauschenbach, B.; Heera, V.

    1988-01-01

    Amorphous metallic systems can be formed either by high-fluence ion implantation of glassforming species or by irradiation of layered metal systems with inert gas ions. Both techniques and experimental examples are presented. Empirical rules are discussed which predict whether a given system can be transformed into an amorphous phase. Influence of temperature, implantation dose and pre-existing crystalline metal composition on amorphization is considered. Examples are given of the implantation induced amorphous structure, recrystallization and formation of quasicrystalline structures. (author)

  20. Ion endash ion correlations in quenched disordered media

    International Nuclear Information System (INIS)

    Bratko, D.; Chakraborty, A.K.

    1996-01-01

    Monte Carlo simulation based on Widom close-quote s test particle method is used to study the behavior of dilute ionic solutes in a quenched disordered medium with ionized obstacles. The structure of the medium is assumed to correspond to that of an ionic fluid equilibrated at certain prequenching temperature T q and permittivity ε q different from the corresponding values at the conditions of observation. The correlations among solute ions display qualitative differences from those observed in annealed systems. The ions of equal sign are attracted to domains of the disordered material characterized by charge opposite to that of the ions. The attraction of ions of the same sign to the same domains results in an apparent attractive contribution to the disorder-averaged interionic potential. At distances sufficiently exceeding the screening length pertaining to the ionized obstacles at the prequenching conditions, the disorder-induced term prevails over the direct Coulombic repulsion and a net attraction is observed. A similar mechanism leads to a long-ranged repulsion between oppositely charged ions. These findings are in agreement with earlier calculations of the disorder-averaged ion endash ion potentials based on the asymptotic Debye endash Hueckel description of the disordered medium. The simulations are also used to estimate the effects of the medium on thermodynamic properties of the embedded ionic solute. The energies and activity coefficients are found to decrease with the product of the prequenching temperature and permittivity, a phenomenon explained in terms of the increase of the potential fluctuations in the disordered medium with growing ε qTq . In spite of its global electroneutrality, the quenched medium displays a strong selectivity with respect to the valency of the solute, the tendency towards absorption increasing with the charge of the ions. (Abstract Truncated)