Platinum-coated mirrors

A double crystal monochromator providing a 6kH of 10-4 is followed by a flat platinum coated mirror for harmonic rejection. A Huber five-circle diffractometer is mounted to allow the 30x30 cm2 two-dimen-... 

Participating research teams Naval Research Laboratory At the NSLS a large number of participating research teams (PRTs) have established beam lines on the NSLS and a number of instruments use diffractometers as well as oscillation cameras. One of these, for instance, is the Naval Research Laboratory (NRL) and National Bureau of Standards PRT as part of this effort, NRL is constructing a materials analysis X-ray beam line. The beam optics design consists of a platinum coated copper pre-mirror dynamically bent to approximate a parabolic cylinder, followed by a fixed-exit double crystal monochromator and a platinum coated fused silica cylinder bent to approximate an ellipsoid. The hutch contains a six-circle diffractometer (Kirkland, Nagel and Cowan 1983). 

The bluish white, hard, yet ductile, metal is inert to all acids and highly non-abrasive. Used for heavy-duty parts in electrical contacts and spinning jets. Reflectors are prepared from the mirror-smooth surfaces (e.g. head mirrors in medicine). Thin coatings provide a corrosion-resistant protective layer, for example, for jewelry, watches, and spectacle frames. The metal is a constituent of three-way catalysts. Rhodium complexes are used with great success in carbonylations (reactions with CO) and oxidations (nitric acid) in industry. Platinum-rhodium alloys are suitable thermocouples. 

Use Alloy with platinum for high temperature thermocouples, furnace windings, laboratory crucibles, spinnerettes in rayon industry electrical contacts, jewelry, catalyst, optical instrument mirrors, elec-trodeposited coatings for metals, vacuum-deposited glass coatings, headlight reflectors. 

The use of hemispherical mirrors for measuring directional/hemispherical reflectance predates the use of integrating spheres for the same purpose by a few years. Paschen (11) placed lamp and platinum black-coated detectors at the center of a hemispherical mirror in order to enhance the detector s absorptance and used this arrangement to determine the constants in Wien s radiation law. Royds (12) positioned a sample and detector at the conjugate foci of a hemispherical mirror in order to measure the reflectance of blackened thermal detectors. In the acknowledgments of a 1911 paper... 

Rhodium is the whitest metal in the platinum group metals and it does not lose its luster under any atmospheres at ordinary temperatures. When rhodium is heated, the protective coating of rhodium oxide forms at 700°C. Further, at llOO C the oxide is dissociated to rhodium and oxygen. Rhodium dissolves in hot sulfuric acid or in aqua regia. Rhodium reacts with a halogen at high temperatures to afford a trihalide [1-6]. Rhodium has a high reflexibility and is used as a reflex mirror. The alloy with rhodium is used in thermocouples, crucibles, catalysts, electrical contact points, heat-resistant materials, corrosion resistant materials, etc. 

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