Soft-X-ray angle-resolved photoelectron spectroscopy (ARPES) with photon energies around 1 keV combines the momentum space resolution with increasing probing depth. The concepts and technical realisation of the new soft-X-ray ARPES endstation at the ADRESS beamline of SLS are described. The experimental geometry of the endstation is characterized by grazing X-ray incidence on the sample to increase the photoyield and vertical orientation of the measurement plane. The vacuum chambers adopt a radial layout allowing most efficient sample transfer. High accuracy of the angular resolution is ensured by alignment strategies focused on precise matching of the X-ray beam and optical axis of the analyzer. The high photon flux of up to 10(13) photons s(-1) (0.01% bandwidth)(-1) delivered by the beamline combined with the optimized experimental geometry break through the dramatic loss of the valence band photoexcitation cross section at soft-X-ray energies. ARPES images with energy resolution up to a few tens of meV are typically acquired on the time scale of minutes. A few application examples illustrate the power of our advanced soft-X-ray ARPES instrumentation to explore the electronic structure of bulk crystals with resolution in three-dimensional momentum, access buried heterostructures and study elemental composition of the valence states using resonant excitation.

We report on the development of a versatile and portable optical profilometer and show its applicability for quick and accurate digitization of 3-D objects. The profilometer is an advanced fringe-projection system that uses a calibrated LCD matrix for fringe-pattern generation, a "hierarchical" sequence of fringe patterns to demodulate the measured phase, and a photogrammetric calibration technique to obtain accurate 3-D data in the measurement volume. The setup in itself is mechanically stable and allows for a measurement volume of about 110.5 m 3 . We discuss the calibration of the sensor and demonstrate the process of recording phase data for several sub-views, generating 3-D "point clouds" from them, and synthesizing the CAD representation of an entire 3-D object by merging the data sets.

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Experimental results for natural convection in a cavity are reported. Both constrained and unconstrained cavity geometries were studied. Detailed velocity profiles were obtained using Laser doppler velocimetry for Rayleigh numbers between 3 × 1010 and 2 × 1011, corresponding to a constant elevated wall temperature boundary condition. Characteristics of two-dimensional and three-dimensional flows obtained with dye flow visualization are discussed, including boundary layer transition to turbulence, flow patterns in the cavity, and flow outside of the cavity. Local Nusselt number is correlated with local Rayleigh number for constrained and unconstrained cavities.

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