Dry seals

Gas Holders Gas is sometimes stored in expandable gas holders of either the hquid-seal or dry-seal type. The hquid-seal holder is a familiar sight. It has a cylindrical container, closed at the top, and varies its volume by moving it up and down in an annular water-filled seal tank. The seal tank may be staged in several lifts (as many as five). Seal tanks have been built in sizes up to 280,000 m (10 X lO fE). The dry-seal holder has a rigid top attached to the sidewalls by a flexible fabric diaphragm which permits it to move up and down. It does not involve the weight and foundation costs or the hquid-seal holder. Additional information on gas holders can be found in Gas Engineers Handbook, Industrial Press, New York, 1966. 

In the case of heavier-than-air purge gas, there is no buoyancy mechanism causing air entry into the stack, and there is thus no incentive to include a dry seal. Unlike a water seal, a dry seal cannot prevent a flashback from traveling upstream if a combustible mixture has been formed by the entry of air into the safety valve or flare headers. It only protects against internal burning flashback... 

Lubrication Dead-End Good under vacuum, mild abrasives metal-metal, dry seals 3-25... 

In dry-seal threads, the roots and crests engage first, eliminating spiral clearance. 

A further options is to fill the dry, sealed boiler with nitrogen at 3 to 5 psig or dry steam at 5 to 15 psig. If steam is employed, traps on the mud drum or other lowest point remove the condensate. Steam storage has the benefit of keeping the boiler warm, which limits the risk of fireside dampness. 

Gas Holders Gas is sometimes stored in expandable gas holders of either the liquid-seal or dry-seal type. The liquid-seal holder is a familiar sight. It has a cylindrical container, closed at the top, and... 

Ordinary (i.e. atmospheric pressure) desiccators are available in the Dry-Seal or ground flange range and have limited use for storage of samples in a dry atmosphere. 

Harvested psilocybian mushrooms can be eaten fresh, or they can be dried, sealed and stored. The best procedure is to dry the mushrooms in a freeze-drier without heat. For most users, this is impossible, so a lamp or oven can do, as long as there is ventilation and the temperature does not exceed 90° F. in a dry atmosphere. (If you use an oven, leave the door cracked open.) A space heater can also be used. Whatever the means, the drying takes at least twenty to twenty-four hours and leaves the mushrooms in a brittle state. 

Keep the slide in the fridge overnight to allow the permafluor to solidify. To avoid the slide from drying, seal the slit between the cover glass and the slide by applying a thin layer of nail polish over the slit. Avoid any nail polish on the surface above or below the samples. 

Gases are stored at atmospheric pressure in wet- or dry-seal gas holders. The wet-gas holder maintains a liquid seal of water or oil between the top movable inside tank and the stationary outside tank. In the dry-seal holder the seal between the two tanks is made by means of a flexible rubber or plastic curtain. Recent developments in bulk natural gas or gas-product storage show that pumping the gas into underground strata is the cheapest method available. High-pressure gas is stored in spherical or horizontal cylindrical pressure vessels. 

Variable-vopor-spoee tank-dry-seal type... 

Properties of Potassium Hexafluoroplatinately).—This salt is mustard yellow. A sample containing some iodine, possibly as iodyl fluoride, was paramagnetic. The low value of the magnetic moment, p = 0-87 B.M. (at 23°), may, in part at least, be due to this impurity. An infrared spectrum, of a Nujol mull, recorded with sodium chloride and cmsium bromide optics, showed two broad, overlapping, absorption bands, with peaks at 590 and 640 cm.. X-Ray powder photographs of the salt have been indexed on the basis of a rhombohedral unit-cell, a = 4-96 A, a = 97-4°, U = 119 9 A. The observed and calculated values for 1/df are given in Table 5. The solid can be stored indefinitely in well-dried, sealed tubes but decomposes... 

Vials of virus-spiked FVIII were freeze dried, sealed with stoppers containing different amounts of moisture, and then heated at 80°C for various times. Moisture in the virus-spiked samples was monitored by Near InfraRed (NIR) spectrometry, whose values had been correlated to loss on drying (LOD) moisture values. After converting the NIR values to LOD moisture levels, the freeze dried/dry heated materials were reconstituted and titrated for residual virus. 

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