Radiation shielding window

The radiation shielding windows are made from high density lead glasses. They are used as viewing windows placed in thick lead and concrete walls for nuclear and radiochemical laboratories. In addition, cerium stabilized borosilicate cover plates are used on the hot side. 

Figure 7. Radiation shielding window showing Ce-stabilized borosilicate glass cover plates (RS 253 G 18) on the hot side, stabilized lead glass (RS 323 G 15), nonstabilized high density lead glass (RS 520) and borosilicate glass cover plate...

ZnBr2 is used as a rayon-finishing agent, as a catalyst, as a gamma-radiation shield in nuclear reactor viewing windows, and as an absorbent in humidity... 

The containment cells are shielded on the front, back, ends, and top by concrete blocks. There is no shielding between containment enclosures. Wall thickness of the blocks is approximately 0.99 m. Shield windows are installed in the front face of the containment enclosures. The inner plate is 2.54 cm radiation-stabilized glass the outer plate is 2.29 cm Pyrex borosilicate glass. Space between these plates is filled with 0.91 m water, which circulates continuously through a filtration-clarification system. Manipulators are mounted in concrete filled lintels. Concrete blocks, totaling 0.77 m thickness, shield the top of the facility. 

Figure 4.4-1 Basic composition of an apparatus for matrix-isolation experiments a) Rotatable cryostat with gas-handling system, b) Sectional view in the level of the matrix support, (1) matrix support, (2) refrigerator, 4-40 K, (3) radiation shield, 77 K, (4) vacuum shroud, (5) infrared window, X KBr, y PE, z quartz glass, (6) spray-on nozzle, (7) synthetic device, e.g., Knudsen cell, (8) turbomolecular pump, p < 10 mbar, (9) to backing pump, (10) transfer line, quartz or stainless steel capillary, (11) needle valve, (12) inert gas inlet, Ne, Ar, N2,..., (13) bulb for gas mixtures, (14) capacity manometer, (15) sample, (16) to high-vacuum system.

Fig. 7-3 Philips diffractometer. The window of a vertical x-ray tube, not shown, would be immediately behind the primary-beam slits. Radiation shield not shown. See also Fig. 15-10. (Courtesy of Philips Electronic Instruments, Inc.)...

Fig. 4.6. Cross-section of an optical continuous-flow cryostat (CF 204 of Oxford Instruments), with the extremity of the removable transfer tube inserted, but without sample holder. The evacuation valve at the top is masked by the sample port. The optional windows on the radiation shield can be replaced by metallic irises to reduce the field of view. This cryostat can be fitted with one or two more optical windows at 90° from the main optical axis for additional excitation, and also with a down-looking window. The arrows indicate the direction of the flow of liquid or gaseous helium. Reproduced with permission from Oxford Instruments...

Such transparent heat mirrors have important application, for example, in combination with cold light mirrors as thermal radiation shields in projection and illumination techniques and potential applications also in solar energy collection, window insulation, etc. 

When assembling insulation layers on top of each other, the edges of aluminum foil layers were lined up in order to have a straight-edged blanket for ease of installation and to avoid radiation windows. Spacer materials were also aligned and extended beyond the edges of the aluminum foil layers in order to avoid thermal short-circuiting of radiation shields. 

Protection of HCF personnel from potentially lethal radiation exposures Zone 2A canyon physical structures (concrete walls, shield steel, shielding windows) Worker safety Provide radiation protection such that worker exposures in continuously occupied areas under normal and abnormal conditions are in accordance with 10 CFR 835 Shield design (Design Feature) Radioactive material control (Administrative Control)... 

These building structures are passive safety features and therefore perform passive safety functions. The only SSC whose mis-operation can directly affect the safety function of these structures is the shield door hydraulic system [a non-safety-reiated (NSR) system], which is used to lower and raise the massive shield doors connecting Rooms 108 and 109, and Room 109 and the Zone 2A canyon. Mis-opeiation of this system with the Room 109/Zone 2A shield door down and radioactive waste in Room 109, can present a radiation hazard to workers at the north end of Room 112. The Zone 2A canyon structures, including the associated shielding windows, and the Room 109 structures are the only HCF SSCs that are required to maintain their safety functions following an earthquake. 

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 14.2 Top view of a cold cell for matrix isolation. The cold window in a metal holder is located inside a vacuum chamber fitted with an inlet port for the matrix gas, external windows, and a port for connection of the vacuum pump. The cold window can be rotated to face the inlet port or the external windows, and it is usual to incorporate a metal radiation shield around it (cooled to ca. 80K) to minimize warming. Matrices are formed by allowing a gas mixture to enter the vacuum chamber through the inlet port, whereupon it will condense on the cold window. 

Initially, DADC polymers were used in military aircraft for windows of fuel and deicer-fluid gauges and in glass-fiber laminates for wing reinforcements of B-17 bombers. Usage in impact-resistant, lightweight eyewear lenses has grown rapidly and is now the principal appHcation. Other uses include safety shields, filters for photographic and electronic equipment, transparent enclosures, equipment for office, laboratory, and hospital use, and for detection of nuclear radiation. 

Deviating from the setup discussed earlier, the y-ray beam can also be consistently collimated by structures other than the absorber holder. If this is the entrance window of the detector, the counter should have a lead shield, and the absorber must be sufficiently large to prevent radiation from passing by. For Mossbauer scattering experiments, the same arguments have to be considered. 

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