871 resultados para The Pockel’s effect,


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Six-period 4 nm GaN/10 nm AlxGa1-xN superlattices with different Al mole fractions x were prepared on (0001) sapphire substrates by low-temperature metal-organic chemical vapor deposition. The linear electro-optic (Pockels) effect was studied by a polarization-maintaining fiber-optical Mach-Zehnder interferometer system with an incident light wavelength of 1.55 mu m. The measured electro-optic coefficients, gamma(13)=5.60 +/- 0.18 pm/V, gamma(33)=19.24 +/- 1.21 pm/V (for sample 1, x=0.3), and gamma(13)=3.09 +/- 0.48 pm/V, gamma(33)=8.94 +/- 0.36 pm/V (for sample 2, x=0.1), respectively, are about ten times larger than those of GaN bulk material. The enhancement effect in GaN/AlxGa1-xN superlattice can be attributed to the large built-in field at the interfaces, depending on the mole fraction of Al. (C) 2007 American Institute of Physics.

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The linear electro-optic (Pockels) effect of wurtzite gallium nitride (GaN) films and six-period GaN/AlxGa1-xN superlattices with different quantum structures were demonstrated by a polarization-maintaining fiber-optical Mach-Zehnder interferometer system with an incident light wavelength of 1.55 mu m. The samples were prepared on (0001) sapphire substrate by low-temperature metalorganic chemical vapor deposition (MOCVD). The measured coefficients of the GaN/AlxGa1-xN superlattices are much larger than those of bulk material. Taking advantage of the strong field localization due to resonances, GaN/AlxGa1-xN SL can be proposed to engineer the nonlinear responses.

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An extensive literature examines the dynamics of interest rates, with particular attention given to the positive relationship between interest-rate volatility and the level of interest rates—the so-called level effect. This paper examines the interaction between the estimated level effect and competing parameterisations of interest-rate volatility for the Australian yield curve. We adopt a new methodology that estimates elasticity in a multivariate setting that explicitly accommodates the correlations that exist between various yield factors. Results show that significant correlations exist between the residuals of yield factors and that such correlations do indeed impact on model estimates. Within the multivariate setting, the level of the short rate is shown to be a crucial determinant of the conditional volatility of all three yield factors. Measures of model fit suggest that, in addition to the usual level effect, the incorporation of GARCH effects and possible regime shifts is important

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We investigate whether therewas a causal effect of income changes on the health satisfaction of East and West Germans in the years following reunification. Our data source is the German Socio-Economic Panel (GSOEP) between 1984 and 2002, and we fit a recently proposed fixed-effects ordinal estimator to our health measures and use a causal decomposition technique to account for panel attrition.We find evidence of a significant positive effect of income changes on health satisfaction, but the quantitative size of this effect is small. This is the case with respect to current income and a measure of ‘permanent’ income.

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Demography theory suggests that high gender diversity leads to high turnover. As turnover is costly for organizations, we examined whether HR policies and practices influence the expected gender diversity-turnover relationship. Survey data were collected from 198 HR decision makers at publicly listed organizations. We found that HR policies and practices that are supportive of diversity moderate the gender diversity-turnover relationship, such that high gender diversity leads to low turnover in organizations with many diversity supportive policies and practices. Results suggest that organizations can avoid the negative consequences of high gender diversity by implementing diversity supportive HR polices and practices.

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Objective Alcohol-related implicit (preconscious) cognitive processes are established and unique predictors of alcohol use, but most research in this area has focused on alcohol-related implicit cognition and anxiety. This study extends this work into the area of depressed mood by testing a cognitive model that combines traditional explicit (conscious and considered) beliefs, implicit alcohol-related memory associations (AMAs), and self-reported drinking behavior. Method Using a sample of 106 university students, depressed mood was manipulated using a musical mood induction procedure immediately prior to completion of implicit then explicit alcohol-related cognition measures. A bootstrapped two-group (weak/strong expectancies of negative affect and tension reduction) structural equation model was used to examine how mood changes and alcohol-related memory associations varied across groups. Results Expectancies of negative affect moderated the association of depressed mood and AMAs, but there was no such association for tension reduction expectancy. Conclusion Subtle mood changes may unconsciously trigger alcohol-related memories in vulnerable individuals. Results have implications for addressing subtle fluctuations in depressed mood among young adults at risk of alcohol problems.

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Molecular dynamics (MD) simulations have been carried out to investigate the defect’s effect on the mechanical properties of copper nanowire with different crystallographic orientations, under tensile deformation. Three different crystallographic orientations have been considered. The deformation mechanism has been carefully discussed. It is found that the Young’s modulus is insensitive to the defect, even when the nanowire’s crystallographic orientation is different. However, due to the defect’s effect, the yield strength and yield strain appear a large decrease. The defects have played a role of dislocation sources, the slips or stacking faults are first generated around the locations of the defects. The necking locations have also been affected by different defects. Due to the surface defect, the plastic deformation has received a large influence for the <001>/{110} and <110> orientated nanowires, and a relative small influence is seen for the <111> nanowire.

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Molecular dynamics (MD) simulations have been carried out to investigate the defect’s effect on the mechanical properties of single-crystal copper nanowire with different surface defects, under torsion deformation. The torsional rigidity is found insensitive to the surface defects and the critical angle appears an obvious decrease due to the surface defects, the largest decrease is found for the nanowire with surface horizon defect. The deformation mechanism appears different degrees of influence due to surface defects. The surface defects play a role of dislocation sources. Comparing with single intrinsic stacking faults formation for the perfect nanowire, much affluent deformation processes have been activated because of surface defects, for instance, we find the twins formation for the nanowire with a surface 45o defect.

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In this paper I examine the recent arguments by Charles Foster, Jonathan Herring, Karen Melham and Tony Hope against the utility of the doctrine of double effect. One basis on which they reject the utility of the doctrine is their claim that it is notoriously difficult to apply what they identify as its 'core' component, namely, the distinction between intention and foresight. It is this contention that is the primarily focus of my article. I argue against this claim that the intention/foresight distinction remains a fundamental part of the law in those jurisdictions where intention remains an element of the offence of murder and that, accordingly, it is essential ro resolve the putative difficulties of applying the intention/foresight distinction so as to ensure the integrity of the law of murder. I argue that the main reasons advanced for the claim that the intention/foresight distinction is difficult to apply are ultimately unsustainable, and that the distinction is not as difficult to apply as the authors suggest.

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The removal of the sulfate anion from water using synthetic hydrotalcite (Mg/Al LDH) was investigated using powder x-ray diffraction (XRD) and thermogravimetric analysis (TG). Synthetic hydrotalcite Mg6Al2(OH)16(CO3)∙4H2O was prepared by the co-precipitation method from aluminum and magnesium chloride salts. The synthetic hydrotalcite was thermally activated to a maximum temperature of 380°C. Samples of thermally activated hydrotalcite where then treated with aliquots of 1000ppm sulfate solution. The resulting products where dried and characterized by XRD and TG. Powder XRD revealed that hydrotalcite had been successfully prepared and that the product obtained after treatment with sulfate solution also conformed well to the reference pattern of hydrotalcite. The d(003) spacing of all samples was found to be within the acceptable region for a LDH structure. TG revealed all products underwent a similar decomposition to that of hydrotalcite. It was possible to propose a reasonable mechanism for the thermal decomposition of a sulfate containing Mg/Al LDH. The similarities in the results may indicate that the reformed hydrotalcite may contain carbonate anion as well as sulfate. Further investigation is required to confirm this.

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This presentation explores molarization and overcoding of social machines and relationality within an assemblage consisting of empirical data of immigrant families in Australia. Immigration is key to sustainable development of Western societies like Australia and Canada. Newly arrived immigrants enter a country and are literally taken over by the Ministry of Immigration regarding housing, health, education and accessing job possibilities. If the immigrants do not know the official language(s) of the country, they enroll in language classes for new immigrants. Language classes do more than simply teach language. Language is presented in local contexts (celebrating the national day, what to do to get a job) and in control societies, language classes foreground values of a nation state in order for immigrants to integrate. In the current project, policy documents from Australia reveal that while immigration is the domain of government, the subject/immigrant is nevertheless at the core of policy. While support is provided, it is the subject/immigrant transcendent view that prevails. The onus remains on the immigrant to “succeed”. My perspective lies within transcendental empiricism and deploys Deleuzian ontology, how one might live in order to examine how segmetary lines of power (pouvoir) reflected in policy documents and operationalized in language classes rupture into lines of flight of nomad immigrants. The theoretical framework is Multiple Literacies Theory (MLT); reading is intensive and immanent. The participants are one Korean and one Sudanese family and their children who have recently immigrated to Australia. Observations in classrooms were obtained and followed by interviews based on the observations. Families also borrowed small video cameras and they filmed places, people and things relevant to them in terms of becoming citizen and immigrating to and living in a different country. Interviews followed. Rhizoanalysis informs the process of reading data. Rhizoanalysis is a research event and performed with an assemblage (MLT, data/vignettes, researcher, etc.). It is a way to work with transgressive data. Based on the concept of the rhizome, a bloc of data has no beginning, no ending. A researcher enters in the middle and exists somewhere in the middle, an intermezzo suggesting that the challenges to molar immigration lie in experimenting and creating molecular processes of becoming citizen.