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Glycerine Analysis
Published in Eric Jungermann, Norman O.V. Sonntag, Glycerine, 2018
Gas chromatography [GC] is an increasingly popular method for separating glycerine from complex mixtures. As early as 1962, Ghanayem and Swann [25] reported successful separation of glycerine from other glycols. They used a 4 ft × ¼ in. column packed with polyphenyl ether and carbowax on Fluo-ropak 80. They found the combination of polyphenyl ether and carbowax to be more applicable than others available at that time (Ucon greases, silicone oils, and Igepol) at separating glycerine from triethylene glycol. Methanolic solutions containing about 5% glycerine and ethylene glycol, diethylene glycol, and triethylene glycol were used for GC analysis. Electronic integrators were not common at that time, so concentrations were calculated from peak heights in the chromatograms. Multiple injections of the same sample gave a relative standard deviation of about 2%.
Tribology of Electronic Connectors: Contact Sliding Wear, Fretting, and Lubrication
Published in Paul G. Slade, Electrical Contacts, 2017
A widely used contact system in telecommunications connectors is illustrated in Figure 7.64. The socket contacts are inlaid with 2.5 μm of DG R-156 and the backplane pin contacts were plated with 1.5 μm of cobalt–gold and lubricated with a polyphenyl ether oil. For cost reduction, it was desired to replace the gold plating with palladium. However, this was not satisfactory, because the palladium plate, although harder than gold, is a poor adhesive wearing material. It displays excessive junction growth, described earlier (Figure 7.8). Since thin gold layers on harder palladium plate were already recognized as capable of providing lubrication function in connectors [63] and on steel in aerospace-bearing applications [209], it was clear that they should be explored further in this application. A bench modeling study [210] was conducted with DG R-156 connector contacts as the rider, and palladium-plated flats were obtained with pure (soft) gold and cobalt (hard) gold platings in a range of thicknesses. A parallel study was conducted with cobalt–gold-plated riders (2 μm thick on 1.25-μm nickel underplate). Both unlubricated and lubricated flats were examined. The lubricant was a polyphenyl ether fluid. Runs were conducted at a load of 200 gf for 200 cycles and a track length of 1 cm. These conditions simulate those of the actual connector.
High-temperature condensation particle counter using a systematically selected dedicated working fluid for automotive applications
Published in Aerosol Science and Technology, 2020
Martin Kupper, Martin Kraft, Adam Boies, Alexander Bergmann
Identifying a suitable working fluid is a crucial part of the realization of a HTCPC. Collings et al. selected their working fluid by an empirical approach (Collings Rongchai, and Symonds 2014). They evaluated six substances and tested four in operation with their HTCPC device: a per-fluorinated polyether, a polyphenyl ether, tetramethyl tetraphenyl trisiloxane and pentaphenyl trimethyl trisiloxane. A sufficient counting efficiency was reported with the two siloxanes. Based on the results of Collings et al., we performed for a systematic study on possible working fluids for high temperature application.
Application of phenol-cresol-formaldehyde resin as an adhesion promoter for bitumen and asphalt concrete
Published in Road Materials and Pavement Design, 2021
Volodymyr Gunka, Yuriy Demchuk, Iurii Sidun, Denis Miroshnichenko, Bemgba B. Nyakuma, Serhiy Pyshyev
The investigations were conducted using the Crystal 2000M gas–liquid chromatograph (GLC). The column of length 3 m was filled with Chromatone + 20% polyphenyl ether 5F4E. The GLC is fitted with a flame-ionisation detector (FID) conditioned at 145°C for 27 min and heated at 10°C/min up to 210°C. The temperature in the evaporator and the detector were set at 250°C. The gas flow rate for helium and hydrogen were set at 30 ml/min, whereas airflow was set at 300 ml/min.