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An inter-laboratory comparison involving three participants (PTB, CAE, TU Graz) was conducted on spectral emissivity measurements using experimental setups covering a temperature range from 1250 K to 4000 K and a spectral range between 0.6 µm and 20 µm. The main objective here was to carry out a European-level assessment of the coherency of spectral emissivity measurements at high temperatures. Three refractory materials (molybdenum, tungsten and isotropic graphite) were selected for this comparison. Samples were machined from the same batch of materials and then sandblasted and thermally annealed (PTB, CAE) to achieve uniform and stable surface properties and reduce potential scattering of results between participants. The spectral emissivity of the three materials was then measured by each of the three participants up to the maximum temperature attainable by the devices used. In the overlapping wavelength range from 600 nm to 1100 nm, all measurement methods were in good agreement with regards to their respective uncertainties. [ABSTRACT FROM AUTHOR]

We report new developments in instrumentation and techniques for both acoustic (speed of sound) and radiometric primary thermometry methods. These include both new cylindrical resonators for extending acoustic gas thermometry to higher temperatures and absolute radiation thermometers incorporating InGaAs detectors to extend primary radiometry to lower temperatures than can be achieved using Si-detector based instruments. These new approaches have been established in order to determine the difference between thermodynamic temperature, T, and the International Temperature Scale of 1990 (the ITS-90), T90, over the temperature range from 430 K to 1358 K as part of the three-year EMPIR project 'Implementing the new kelvin 2' (InK2). This paper describes the facilities and measurement methodologies for measuring T—T90 at each of the different institutes, along with an assessment of the target uncertainties. The work is ongoing, but we anticipate that the results of these measurements will ultimately be pooled to provide consensus values of T—T90 with associated estimated uncertainties. These consensus values will initially feed into the technical annex of the mise en pratique for the definition of the kelvin (MeP-K-19) and, if required, will be used to help to provide a foundation for any future temperature scale. [ABSTRACT FROM AUTHOR]

To improve the dynamic emissivity measurement, which is based on the laser-flash method, an array spectrometer is characterized regarding its spectral radiance responsivity for a spectrally resolved emissivity measurement above $$1000\,$$ K in the wavelength range between $$550\,$$ nm and $$1100\,$$ nm. Influences like dark signals, the nonlinearity of the detector, the size-of-source effect, wavelength calibration and the spectral radiance responsivity of the system are investigated to obtain an uncertainty budget for the spectral radiance and emissivity measurements. Uncertainties for the spectral radiance of lower than a relative $$2\,\%$$ are achieved for wavelengths longer than $$550\,$$ nm. Finally, the spectral emissivity of a graphite sample was determined in the temperature range between $$1000\,$$ K and $$1700\,$$ K, and the experimental data show a good repeatability and agreement with literature data. [ABSTRACT FROM AUTHOR]

Various studies have reported adjustment problems experienced by gay, lesbian, and bisexual (GLB) adolescents. A primary purpose of this paper is to critically review this literature. Difficulties that have been studied include past suicide attempts, substance use and abuse, conduct problems, and academic concerns. For example, a considerable number of GLB youth report a history of suicide attempts, with prevalence rates ranging from 11 to 42%. However, among other methodological concerns, studies in this area have not used a comparison sample of heterosexual youths. Characteristics of development particular to GLB adolescents are described, the empirical research on adjustment issues is reviewed, and potential risk and protective factors for GLB youths are discussed. [ABSTRACT FROM AUTHOR]

Latinx sexual minority adolescents and young adults experience sexual orientation-based victimization at school and may internalize these heterosexist experiences. However, social support may buffer the deleterious contributions of sexual orientation-based victimization. The current study explored associations between sexual orientation-based victimization and internalized homonegativity in different social contexts (family, peer, school adult) and across development (high school versus college) among 238 Latinx sexual minority adolescents and young adults ( M = 19.03, SD  = 2.28). Results indicated that sexual orientation-based victimization was positively associated with internalized homonegativity among Latinx sexual minority adolescents and young adults. Such associations were moderated by family support and the school level in the family context, such that in high school, family support exacerbated the association between sexual orientation-based victimization and internalized homonegativity. Yet, in college, family support mitigated that association. Findings also indicated that peer support exacerbated the association between sexual orientation-based victimization and internalized homonegativity in high school and college. No moderation of school adult support emerged in the context of school adults. Findings support the application of the minority stress model in Latinx sexual minority adolescents and young adults and highlight the complex moderating effect of social support across social contexts and development.