375 research outputs found

    A diode laser stabilization scheme for 40Ca+ single ion spectroscopy

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    We present a scheme for stabilizing multiple lasers at wavelengths between 795 and 866 nm to the same atomic reference line. A reference laser at 852 nm is stabilized to the Cs D2 line using a Doppler-free frequency modulation technique. Through transfer cavities, four lasers are stabilized to the relevant atomic transitions in 40Ca+. The rms linewidth of a transfer-locked laser is measured to be 123 kHz with respect to an independent atomic reference, the Rb D1 line. This stability is confirmed by the comparison of an excitation spectrum of a single 40Ca+ ion to an eight-level Bloch equation model. The measured Allan variance of 10^(-22) at 10 s demonstrates a high degree of stability for time scales up to 100 s.Comment: 8 pages, 11 figure

    El complejo karstico-yesifero subterráneo "Pedro Fernández" (Estremera, provincia de Madrid)

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    [Resumen] Se han analizado los factores originales de este morfosistema kárstico subterraneo, detallan do los procesos responsables de su génesis, así como la morfolmgía interior. Diferenciando los tipos de galerias y su evolución. Al mismo tiempo, se aportan determinadas consideraciones acerca de la sedimentación interior de la cavidad, su tipología e interpretación de su significado[Resumé] On a analysé les facteurs qui ont originé ce morphosysthéme karstique souterrain, en detallant le procesus responsable de leur genére, ainsi que leur morphilogie intérieure. En distinguant les types de galeries et leur évolution. Eu méme temps, on apporte certaines considerations données á propos de la sédimentation, sa typologie et interprétation de sa signification

    Claves internas y externas en la habituación a largo plazo

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    Taxonomy and hierarchy of psychological abuse strategies in intimate partner relationships

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    This study focuses on the analysis from of a psychosocial perspective of the components of psychological abuse in intimate partner relationships. Following a review of studies on the subject, the main objective that emerged was the need for a new taxonomy of strategies of psychological abuse accompanied by the corresponding operational definitions. After the proposal of this new classification, a second objective emerged that consisted of submitting it for evaluation by a group of experts through a Delphi study, in which thirty-two experts from the academic and professional worlds participated. These experts were asked to assess the suitability of the system categories, and to grade quantitatively the severity of the impact made by each of the strategies on the global phenomenon of psychological abuse in couples. The results show that the experts ratified the new classification of strategies and their operational definitions, thus endorsing their content and construct validity. In addition, they classified the strategies based on their degree of severity; those of an emotional nature were considered the severest, followed by those related to the immediate context, with those of a cognitive type in third place, and lastly, the behavioural ones. Finally, we discuss the results, and their implications. Este estudio se centra en analizar los componentes del abuso psicológico en la violencia de pareja adulta y contra la mujer desde un enfoque psicosocial. Tras realizar una revisión de los estudios sobre el tema, se plantea como primer objetivo el proponer una nueva taxonomía de estrategias de abuso psicológico, acompañadas de sus respectivas definiciones operativas. A partir de esta nueva clasificación, se traza un segundo objetivo que se centra en someter esta clasificación al juicio de un grupo de expertos a través de un estudio Delphi, en el que han participado 32 expertos de los ámbitos académico - universitario y profesional. Estos expertos debían juzgar la adecuación del sistema de categorías, además de evaluar cuantitativamente la severidad que aporta cada una de las estrategias al fenómeno global del abuso psicológico en la pareja. Los resultados muestran que los expertos ratifican la nueva clasificación de estrategias y sus definiciones operativas, avalando así su validez de contenido y constructo. Además, jerarquizaron las estrategias de abuso, atribuyendo mayor severidad a las de tipo emocional, seguidas de las relacionadas con el contexto cercano, de las de tipo cognitivo y las de carácter conductual. Se discuten los resultados, sus limitaciones y las implicaciones que pueden derivarse de ellos

    Numerical simulation of a 3-D gas-solid fluidized bed: Comparison of TFM and CPFD numerical approaches and experimental validation

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    This paper presents the results of a 3-D numerical simulation of a freely bubbling fluidized bed, based on the Eulerian¿Lagrangian approach, using the software Barracuda (CPFD-Barracuda). The main results obtained were assessed in terms of frequency analysis, bubble pierced length, bubble size, bubble passage frequency and bubble velocity. The results obtained were also compared with experimental data obtained in a 3-D fluidized bed using pressure and optical probes, and with the numerical results using the more common Eulerian-Eulerian approach, implemented in the commercial software Fluent (TFM-Fluent). The results show that CPFD-Barracuda satisfactorily predicts the global behaviour of bubbling beds with a low computational cost, although it computes smaller bubble sizes and lower bubble velocities than TFM-Fluent and experiments. Additionally, the spectra of pressure and particle volume fraction obtained with CPFD-Barracuda resemble those from the experiments and the TFM-Fluent simulations, but with a larger contribution of lower frequencies. The peaks of the pressure spectra from CPFD-Barracuda are close to those from the experiments and the TFM-Fluent simulations, whereas those in the solid volume spectra seem to be underestimated by CPFD-Barracuda. The results also indicate that the particle fraction threshold value chosen to distinguish bubbles contours notably influences the results of the bubble characteristics, especially for TFM-Fluent, whereas CPFD-Barracuda is less sensitive to this threshold value.This work was partially funded by the Ministerio de Economía y Competitividad (Projects ENE2016-78908-R and RTI2018-096664- B-C21 (MICINN, FEDER/UE)) of the Spanish Government, the Regional Government of Castilla-La Mancha (project SBPLY/17/180501/000412) and the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) (RED2018-102431-T)

    Development and validation of the scale of psychological abuse in intimate partner violence (EAPA-P)

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    Background: In the context of intimate partner violence, psychological abuse (PA) has progressively gained scientific relevance. Even so, a greater effort is needed to define and evaluate psychological intimate partner abuse. A new exhaustive and operative taxonomy of PA strategies leads to the contribution of a new evaluation instrument. Method: Participants were 101 women between 24 and 82 years old, who were abused by their partners and attended to in different municipal Catalan services, specialized in the topic. Results: The analyses have shown the suitability of a 19-item instrument divided into two factors: (1) direct PA strategies and (2) indirect PA strategies. The former includes strategies that affect the emotional, cognitive and behavioral dimension of the victim. The latter includes items that measure the amount of control and domination over the victim’s context. This scale has adequate psychometric properties in terms of score reliability and the validity of the relationship with other women’s health variables. Conclusions: The EAPA-P, created based on a new definition and taxonomy of the forms of PA, is presented as a valid instrument to detect and measure intimate partner PA

    Flow and heat transfer analysis of a gas-particle fluidized dense suspension in a tube for CSP applications

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    This work presents a numerical study of the flow of particles in a gas–particle fluidized dense suspension for CSP applications using the Multi-Phase Particle in Cell (MP-PIC) method, implemented in CPFD-Barracuda software. The study covers two different numerical simulations. The first is a cold and isothermal model in which the fluctuations and control of the mass flow of particles ascending along the vertical tube was studied. In the second, a high-temperature boundary condition was imposed on the external surface of the tube and the energy equation was solved. In this second case, the heat transfer coefficient between the inner surface of the tube and the particles was numerically computed. The numerical results in the cold model are highly consistent with experimental data available in the literature (with values up to 150 kg/h and differences of approximately ±10 kg/h) and underline the significant impact of the pressure at the bottom of the bed and of the aeration flow rate on the mass flow of particles. The results of the non-isothermal case present heat transfer coefficients in the range of 300–400 W∕(m2 K) with transient fluctuations during the fluidization process. These fluctuations may be an influence on the mechanical damage of the tube, which is exposed to high levels of concentrated irradiation.This work was partially funded by the project PID2021-127322OB-I00, funded by the Ministerio de Ciencia e Innovación MICIN/AEI/10.13039/501100011033/ and by FEDER Una manera de hacer Europa; Project SBPLY/21/180501/000017, funded by the Regional Government of Castilla-La Mancha and by FEDER Una manera de hacer Europa; Project RED2018-102431-T, funded by the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) and Project 2020-GRIN-28725, funded by Universidad de Castilla-La Mancha
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