Buehler Instruments

The KHT was devised in 1939 by F. Knoop. A Knoop diamond indenter may be used in a Tukon Hardness Tester (or in a Buehler Instrument Model 1600-6400). The indentation produced by the KHT resembles that made by a pyramid-shaped diamond indenter (developed by the U.S. National Bureau of Standards). The apical angles are 130° and 172°. Thus, a narrow, rhombus-shaped indenter is used to produce a rhomboid-shaped impression, as seen in Fig. 1.61. 

Electrochemical Instrumentation. For the Ru complexes, a 1 cm diameter platinum disk brazed onto a brass holder was used as a working electrode. It was masked with ChemGrip (a teflon based epoxy) except for the upper face. Prior to use, it was polished with 1 micron diamond paste (Buehler) and rinsed with water, acetone and methanol. The working electrode for each Os complex was the uppermost platinum layer of a platinum/carbon layered synthetic microstructure (LSM) (Energy Conversion Devices). The LSM consisted of 200 layer pairs of carbon and platinum whose thicknesses were 24.4 and 17.0 A, respectively and where platinum was the outermost layer. The LSM was placed in 1.0 M H2SO4 and cleaned... 

Buckbee Mears Co., 245 East 6th Street, St Paul, MN 55101, USA, (612) 228 6400 Buehler, Optical Instruments Division, 41 Waukegan Road, Lake Bluff, IL, USA, 60044 (312)295 6500... 

Electrodes and Instrumentation. Electrodes were mechanically polished with one micron diamond paste (Buehler) until satisfactory background voltammograms were obtained. A disposable, 20 ml scintillation vial served as a convenient, one-compartment electrochemical cell. 

Ver Verdes, C.L., Buehler, S.A., Perrin, A., Flaud, J.-M., Demaison, J., Wlodarczak, G., Colmont, J.-M., Cazzoli, G., Puzzarini, C. A sensitivity study on spectroscopic parameter accuracies for a mm/submm limb sounder instrument, J. Mol. Spectrosc. 229 (2005) 266-275. 

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