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Fused quartz windows

The cavity of Prob. 8-73 has a fused-quartz window placed over it, and the cavity is assumed to be perfectly insulated with respect to conduction and convection loss to the surroundings. The cavity is exposed to a solar irradiation flux of 900 W/m2. Assuming that the quartz is nonreflecting and r = 0.9, calculate the equilibrium temperature of the inside surface of the cavity. Recall that the transmission range for quartz is 0.2 to 4 /xm. Neglect convection loss from the window. The surroundings may be assumed to be at 20°C. [Pg.481]

A schematic diagram of the discharge chamber is shown in Figure 199. Its body is essentially a cross made of 6-mm o.d. borosilicate glass tubing its vertical arms are approximately 4.5 cm long. Its front end is a flange (2.5-cm diam.) to which a fused quartz window is cemented with a suitable epoxy adhesive. This window can be replaced by a plano-convex fused quartz lens, if desired. [Pg.477]

Figure 9 Tungsten tube furnace for growing AIN crystals devised by Slack and McNelly. A, alumina C, tungsten crucible F, flat foil tungsten radiation shields H, radio frequency beating coil J, water cooling jacket Q, fused quartz bousing R, rolled foil radiation shields S, tungsten support tube T, tungsten susceptor tube W, clear fused quartz window Z, rubber O-ring seal. Figure 9 Tungsten tube furnace for growing AIN crystals devised by Slack and McNelly. A, alumina C, tungsten crucible F, flat foil tungsten radiation shields H, radio frequency beating coil J, water cooling jacket Q, fused quartz bousing R, rolled foil radiation shields S, tungsten support tube T, tungsten susceptor tube W, clear fused quartz window Z, rubber O-ring seal.
A typical configuration for a RAS spectrometer using a PEM is shown in Figure 3.4.1.17. When working with a sample in a UHV environment, the polarization-sensitive elements (polarizer, PEM, and analyzer) are all outside the experimental UHV chamber and a strain-free fused quartz window is used for... [Pg.350]

Useful fransparenf materials for cell windows, lenses, and so on are Pyrex glass for fhe visible and fused quartz for fhe visible and near-ulfraviolef. [Pg.62]

The electrochemical cell used in our laboratory has been fully described elsewhere (5). The cell body is made of chemically inert Kel-F and the electrode is mounted on a piston so that its surface can be pushed to the optical window, to a spacing of the order of 1-3 microns, in order to minimize the signal from the bulk electrolyte. For Raman scattering spectroscopy the window is of flat fused quartz, and the exciting laser beam is incident at about 60°. The scattered light is collected off-normal, but the geometry is not critical for SERS due to the high sensitivity. Details on the SERS measurements in our laboratory have been reported previously (6,7). [Pg.323]

Optical Applications. Vitreous silica is ideal for many optical applications because of its excellent ultraviolet transmission, resistance to radiation darkening, optical polishing properties, and physical and chemical stability. It is used for prisms, lenses, cells, windows, and other optical components where ultraviolet transmission is critical. Cuvettes used in scatter and spectrophotometer cells are manufactured from fused silica and fused quartz because of the transmissive properties and high purity (222). [Pg.512]

High silica (Vycor 96.5% fused quartz 100%) Outstanding thermal resistance Difficult to make very expensive Spacecraft windows labware fiber optics... [Pg.165]

The filter cell, the reaction cell, and the windows of the bath were all of fused quartz. The lens, bath, and photomultiplier tube housing were rigidly mounted on an optical bench. Temperature control inside the bath was achieved by using either a circulating water pump ( 0.25°C.) or a hot air blower (=fcl°C.). [Pg.291]

Fused quartz transmits 90 percent of the incident thermal radiation between 0.2 and 4 fim. Suppose a certain heat source is viewed through a quartz window. Vhat heat flux in watts will be transmitted through the material from blackbody radiation sources at (a) 800°C, (b) 550°C, (c) 250°C, and (d) 70°C ... [Pg.473]

A dilute mixture of a solute in supercritical fluid is introduced into a high pressure optical cell, equipped for 90 degree detection with a 1.3 cm pathlength. The windows are 6 mm thick fused quartz discs. The pressure in the optical cell is measured with a Texas Instruments model 140 pressure gauge, which has an accuracy of 0.2 bar. The temperature in the optical cell is controlled with a custom built precision temperature controller that is good to 0.02 C. The temperature is measured by recording the resistance of an Omega type 44032 thermistor. The... [Pg.17]

Suprasil down to 185 nm and fused quartz down to 160 nm. Hence fluoiimeters which primarily detect long-wavelength radiation (fluorescent radiation) are often equipped with type S-4 detectors (Tab. 4), whose windows absorb a part of the short-wavelength radiations. [Pg.22]

Our single-molecule detector is based on the sheath-flow technology introduced by Keller s group. A 10 pm inner diameter, 142 pm outer diameter, and 29 cm long fused silica capillary is introduced into the flow chamber of a sheath flow cuvette [40]. The volume contained within this capillary is about 25 nL. The locally constructed sheath flow cuvette has 1-mm thick quartz windows and a 150 pm square flow chamber. The flow chamber is held within a stainless steel holder that is held at ground potential. Buffer is introduced into the cuvette, drawing analyte from the tip of the capillary as a fine stream in the center of the flow chamber. [Pg.234]

Most spectrometers use tungsten-halogen lamps with quartz windows. Cells for absorption measurements are usually quartz or fused silica transparent up to about 3000 nm. Cell lengths vary from 0,1 to 10 cm. Detectors range from PbS and PbSe photoconductors to InSb and InAs photodiodes. Array detectors, such as InGaAs detectors, have also become available for the region. Several commercial UV-visible spectrophotometers are designed to operate from 180 to 2500 nm and can thus be used to obtain NIR spectra. [Pg.245]


See other pages where Fused quartz windows is mentioned: [Pg.176]    [Pg.70]    [Pg.375]    [Pg.16]    [Pg.229]    [Pg.211]    [Pg.128]    [Pg.89]    [Pg.176]    [Pg.70]    [Pg.375]    [Pg.16]    [Pg.229]    [Pg.211]    [Pg.128]    [Pg.89]    [Pg.28]    [Pg.22]    [Pg.82]    [Pg.74]    [Pg.1506]    [Pg.1640]    [Pg.227]    [Pg.128]    [Pg.209]    [Pg.72]    [Pg.170]    [Pg.6528]    [Pg.52]    [Pg.206]    [Pg.71]    [Pg.179]    [Pg.90]    [Pg.6527]    [Pg.474]    [Pg.296]    [Pg.348]    [Pg.299]    [Pg.223]    [Pg.259]   
See also in sourсe #XX -- [ Pg.62 ]

See also in sourсe #XX -- [ Pg.62 ]




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Quartz windows

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