This paper introduces a new set of certified reference materials designed to aid scientists and conservators working in cultural heritage fields with quantitative X-ray fluorescence analysis of historical and prehistoric copper alloys. This set has been designated as the Copper CHARM Set (Cultural Heritage Alloy Reference Material Set). The Copper CHARM Set is designed to be used by a wide range of museum-, art-and archaeology-oriented scientists and conservators to help improve the accuracy and range of their calibrations for quantitativeED-XRF spectrometry of copper alloys, and also increase the number of elements that can routinely be quantified. In addition, the common use of a single core set of the reference materials is designed to significantly improve inter-laboratory reproducibility, allowing greater data sharing between researchers and thus furthering possibilities for collaborative study.

Opera performance conveys both visual and auditory information to an audience, and so opera theaters should be evaluated in both domains. This study investigates the effect of static visual and auditory cues on seat preference in an opera theater. Acoustical parameters were measured and visibility was analyzed for nine seats. Subjective assessments for visual-only, auditory-only, and auditory-visual preferences for these seat positions were made through paired-comparison tests. In the cases of visual-only and auditory-only subjective evaluations, preference judgment tests on a rating scale were also employed. Visual stimuli were based on still photographs, and auditory stimuli were based on binaural impulse responses convolved with a solo tenor recording. For the visual-only experiment, preference is predicted well by measurements taken related to the angle of seats from the theater midline at the center of the stage, the size of the photographed stage view, the visual obstruction, and the distance from the stage. Sound pressure level was the dominant predictor of auditory preference in the auditory-only experiment. In the cross-modal experiments, both auditory and visual preferences were shown to contribute to overall impression, but auditory cues were more influential than the static visual cues. The results show that both a positive visual-only or a positive auditory-only evaluations positively contribute to the assessments of seat quality.

Photolysis of the vapour of hexafluoroacetylacetone HFAA in its enolic form involves decomposition by two independent primary processes, one of which is a novel elimination of H F giving 2,2-difluoro-2,3-dihydro-5trifluoromethylfuran-3-one:The HF is not vibrationally excited. CF2 radicals which, if HFAA is present, undergo an insertion into the enolic OH bond, Photolysis of the cyclic product of reaction ( 5 ) yieldsCF, + CF,C=CHCOCF, -+ CF,C=CHCOCFx I OCF,H I OH The infrared, ultraviolet, nuclear magnetic resonance, and mass spectra of HFAA and of the products of reactions (5) and (6) have been measured. Approximate quantum yields for reactions (1) and ( 5 ) have been obtained. Both + I and +5 depend on pressure and the ratio increases with temperature and decreased wavelength of photolysing light. It is proposed that the ratio 43/45 increases as the vibrational energy of electronically excited HFAA increases.

The acoustic environment of an auditorium stage can enhance the ability of musicians or actors to hear each other clearly. This is assessed through a set of parameters called 'stage support'. Stage support parameters are conventionally measured using an omnidirectional source and microphone separated by 1 m on the stage. Various stage support parameters are derived from energy ratios of the direct and reflected (or reverberant) sound in the impulse response from source to microphone. The present paper examines the possibility of assessing the directional characteristics of the reflected soundfield by using a multidirectional microphone. Measurements were made in the Sydney Theatre Company's 'Sydney Theatre' with and without a stage set. The microphone used allows first order spherical harmonic decomposition of the soundfield, which was transformed to cardioid components for orthogonal directions (upstage, downstage, left, right, up and down), as well as for horizontal rotations of the cardioid microphone. These were used to calculate directional stage support values. Results demonstrate the potential of this simple extension of standard stage support measurement by showing the acoustical effect of the set.

The reaction CzF5 +HCl+C2F5H+Cl k 2 was investigated over the range 23-152°C using perfluoropropionic anhydride as a photolytic source of CzF5 radicals. Arrhenius parameters are given by log {k2/cma mol-l s-l) = (10.80~0.14)-(4240~230)/0 where 0 = 2.303 RT/cal mol-l. The reactivity of C2F5 radicals with polar and non-polar substrates is discussed. The above value of Et leads to a value of the bond dissociation energy D(C2F5-H) = 103.1 &1.5 kcal mol-' in good agreement with previous work.