Tungsten lamps

H2 and D2 lamp tungsten lamp Xe arc lamp Nernst glower globar... 

Tungsten with the addition of as much as 5% thoria is used for thermionic emission cathode wires and as filaments for vibration-resistant incandescent lamps. Tungsten—rhenium alloys are employed as heating elements and thermocouples. Tantalum and niobium form continuous soHd solutions with tungsten. Iron and nickel are used as ahoy agents for specialized appHcations. 

Wolframit, n. (Min.) wolframite. Wolfram-lampe, /. tungsten lamp, metall, n. metallic tungsten, -ocker, m. tungstic ocher, tungstite. -oxyd, n. tungsten oxide, -salz, n. tungsten salt. 

In the continuous wave (CW) experimental setup a sample is constantly illuminated by a probe beam and the steady state change in the transmission is detected (see Fig. 7-1). An argon ion laser has been used to generate the pump beam and the probe beam was from an incandescent lamp (tungsten or others), producing a broad spectrum (0.5 to 5 pm) [6]. Both pump and probe beams are directed onto the sample film and the transmitted probe light is collected, filtered through a monochromator, and detected by a photodetector. Both the pump and the probe... 

Phillips 4025 Deuterium lamp Tungsten lamp (accessory) 190-380 190-600 0.005-1.28 (9 ranges) 10 4 at 230 nm... 

Tungsten lamp Tungsten Near-IR Best for between 33,000 and 400 cm ... 

Light source Tungsten filament lamp LEDs, xenon flashlamp LEDs Tungsten halogen lamp Xenon flash- lamp Mercury vapour lamp Tungsten halogen lamp... 

Many other types of light sources can also be used for photopolymerization reactions, for example, low-pressure mercury arcs, flash lamps, fluorescent lamps, tungsten halide sources, and even lasers. A complete review of light sources used in photopolymerization reactions can be found in Reference 18,... 

Figure 6.25 (Top row) Atomic and background absorption with a bne source (HCL, EDL). (Bottom row) Atomic and background absorption with a continuum source (deuterium lamp, tungsten-filament lamp). The width (x-axis) of each diagram is the spectral slit width. [FiDm Beaty and Kerber, used with permission of PerkinElmer, Inc. (www.perkinelmer.com).]...

Just as the bulb in a table lamp has a finite lifetime, so do the ultraviolet/ visible (UV/Vis) detector lamps (tungsten and deuterium see Chapter 4) in HPLC systems. Light intensity decreases with time due to the evaporation of internal metal components and coatings. Lamps deteriorate with age and use according to most manufacturers, lamps have a lifetime of about 1,000 hours. The lifetime is defined as being the time at which 50% of the light intensity remains. After this time has elapsed, the lamp should be replaced. 

Type of lamp Incandescent lamps Tungsten halogen High pressure mercury High pressure sodium... 

Radiation source Hydrogen or deuterium lamp Tungsten filament lamp, carbon arc (less used)... 

Figure 2 Schema of TLC densitometer CD 60 (DESAGA). 1. Deuterium lamp, tungsten halogen lamp, and mercury vapor lamp. 2. Minor. 3. Entry slit. 4. Mirror. 5. Diffraction grating. 6. Beam slit. 7. Condenser. 8. Photomultiplier. 9. TLC plate. 10. IBM PC compatible.

The light intensity per watt for sodium vapor lamps far exceeds that of fluorescent lamps, high-pressure mercury vapor lamps, tungsten halogen lamps, and incandescent bulbs. 

Other sources are incandescent electric lamps (tungsten), the Welsbach mantle, hot glass, and the quartz-jacketed high-pressure mercury arc. The tungsten ribbon filament lamp makes a good secondary standard (compared to a primary blackbody) in the near... 

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