Argon cylinders

Gases (cylinders). Argon and hydrogen, equipped with two-stage regulating valves. 

For distributing larger quantities of gaseous helium, argon, and occasionally neon, a number of large, horizontal, compressed gas cylinders are manifolded on tmck semitrailers (called tube trailers) or railroad cars. Like individual cylinders, these serve both as transport containers and rental storage containers. Capacities of tube trailers range from about 300 to 5,000 m (10,000—175,000 fT) of gas. 

Fig. 10. Molecular-transmission probability (a) for circular cylinder (b) having two restricted ends where the soHd line represents fraction transmitted without wall encounter and the dashed line, prediction of this fraction by the formula vs L,/R. (R/Rq) 1, oo 2, 3 3, 2 4, 1.5 5, 1.0. (0) Argon,...

As indicated in Fig. 21.3, for both atomic absorption spectroscopy and atomic fluorescence spectroscopy a resonance line source is required, and the most important of these is the hollow cathode lamp which is shown diagrammatically in Fig. 21.8. For any given determination the hollow cathode lamp used has an emitting cathode of the same element as that being studied in the flame. The cathode is in the form of a cylinder, and the electrodes are enclosed in a borosilicate or quartz envelope which contains an inert gas (neon or argon) at a pressure of approximately 5 torr. The application of a high potential across the electrodes causes a discharge which creates ions of the noble gas. These ions are accelerated to the cathode and, on collision, excite the cathode element to emission. Multi-element lamps are available in which the cathodes are made from alloys, but in these lamps the resonance line intensities of individual elements are somewhat reduced. 

Reagent setting Argon cylinder pressure Argon flow rate... 

A 1.5 M solution of butyllithium in hexane was purchased from Aldrich Chemical Company, Inc. Aliquots were transferred to a 100-mL graduated cylinder, stoppered with a rubber septum using a 15-gauge cannula and argon. 

Disodium pentacarbonylchromate is prepared by adding a solution of sodium naphthalenide (88 mmol) in THF (160 mL) to chromium hexacarbonyl (40 mmol) in THF (240 mL). The resulting solution of disodium pentacarbonylchromate is transferred to a 500-mL graduated cylinder (to estimate the concentration). This solution can be stored at -20 °C under argon for at least two months. 

An extreme example of the discrepancy between true pressure pT and indicated pressure pi in pressure measurement is the admission of air to a vacuum system with argon from a pressure cylinder to avoid moisture (pumping time). According to Fig. 3.11, one would obtain a p, reading of... 

Low-pressure mercury lamps consist most frequently of a quartz cylinder with electrodes on both ends, although other shapes are also produced. Inside the lamp is a mixture of mercury and argon at a pressure of 10 to 10 Torn The emission from this lamp is 254 nm, and with high-quality quartz, some light with 189 nm wavelength is produced. Low-pressure lamps are of low power, and therefore are not used for the cure of coatings, but are well suitable for applications where slow cure rate is tolerated, such as liquid crystal displays or in resist technology for the production of microchips. 

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