A very extensive compilation of Stark widths and shifts for more than 125 Ar II visible spectral lines is presented in this work. These atomic parameters have been measured in a pulsed discharge lamp by using different mixtures of pure argon or argon and helium. The electron density, which typically ranges from 0.2 to 2.0 × 10 23 m −3 has been determined interferometrically and, in the case of pure argon plasmas, also spectroscopically from H α -Stark broadening. The Ar II excitation temperature (15 000-31 000 K) has been determined by Boltzmann-plot techniques from the intensity of Ar II lines. A detailed description of all the relevant points in this kind of measurement is given. Comparisons with most of the data published about this topic for Ar II are also included.
The Sport Motivation Scale was developed in French and later translated into English and validated by Pelletier, et al. in 1995. It is based on the principles of self-determination theory. In this study the scale was translated into Spanish to assess and validate it for a sample of 275 athletes (78 women and 197 men) whose mean age was 21.3 yr. (SD=3.8) and who represented eight sports (track and field, tennis, swimming, waterpolo, soccer, basketball, handball, and volleyball). The Spanish version showed satisfactory internal consistency (Cronbach alpha of .70 to .80) and temporal stability (test-retest r = .69 to .74) over a 4-wk. period. A confirmatory factor analysis partially supported the seven-factor structure. Correlations among the subscales indicated a simplex pattern supporting the construct validity of the scale. Sex differences were found. Taken together, these findings support use of the Spanish version for assessment of motivation in sport.
Microsamples collected on 27 major paintings by Old European Masters dating from the 14th to the late 19th centuries were analyzed using synchrotron-based X-ray diffraction. Two complementary analytical configurations were used at beamlines ID22 (high angle resolution) and ID21 (high lateral resolution), in order to highlight markers of the different grades of the lead white pigments (mixture of cerussite PbCO and hydrocerussite Pb(CO)(OH)). Rietveld analysis and crystalline phases mapping at the microscale revealed the composition and microstructure of the pigments, shedding light on the preparation recipes and pigment choices of the artists through History.
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