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Another test is the total oxygen demand (TOD) test, which oxidizes the waste in the presence of a catalyst at 900°C in a stream of air. Under these harsh conditions, all the carbon is oxidized to CO2. The oxygen demand is calculated from the difference in oxygen content of the air before and after oxidation. The resulting value of TOD... [Pg.308]

Ship-shaped FPSOs must be designed to weather vane i.e. must have the ability to rotate in the direction of wind or current. This requires complex mooring systems and the connections with the well heads must be able to accommodate the movement. The mooring systems can be via a single buoy or, in newer vessels designed for the harsh environments of the North Sea, via an internal or external turret. Figure 10.33 shows a schematic of the Shell-BP Foinaven FPSO. [Pg.266]

In principle any PC can be used, provided it has the necessary computing power and memory installed and can be equipped with the processor board, which requires an empty PCI slot in the PC. For using the system in the field, it is recommended to use an industrial PC, designed to be used in a harsh environment. [Pg.785]

We discuss classical non-ideal liquids before treating solids. The strongly interacting fluid systems of interest are hard spheres characterized by their harsh repulsions, atoms and molecules with dispersion interactions responsible for the liquid-vapour transitions of the rare gases, ionic systems including strong and weak electrolytes, simple and not quite so simple polar fluids like water. The solid phase systems discussed are ferroniagnets and alloys. [Pg.437]

The cleaning or depassivation eflect is of great importance in sonoelectrochemistry, as it can be employed to wash off surface-adsorbed species and reduce blocking of the electrode by adsorption of reaction products. This eflect has been reported, for example, for the depassivation of iron electrodes and for the removal of deposits and in the presence of polymer films on the electrode surface. However, damage of the electrode surface, especially for materials of low hardness such as lead or copper, can also occur under harsh experimental conditions and applied intensities [70, Tf, 80]. [Pg.1943]

There is also the promise of finding large amounts of deep methane formed not from biomass but by some abiological processes from carbonates or even carbides formed from carbon-containing asteroids that hit the earth over the ages under the harsh prebiological conditions of our planet. [Pg.210]

Any commercially available vacuum pump is perfectly fine for the underground chemist s needs but the best kind to buy is a diaphragm pump, which is more resistant to the often-harsh chemical vapors that are sucked through it. Most vacuum pumps cost about 100- 200. However, the stronger the vacuum the better. If a chemist is looking to pull 1mm of Hg (don t ask) like the girls in the chemistry papers do then she can be looking at a turbovac that can run well over 5000. [Pg.16]

This is similar to the Friedel-Crafts method but is less harsh and has been proven successful at producing safrole. In a very small flask is added 7.2g of allyl chloride, 34.3g 1,3-benzodioxole and 0.15g powdered Cu (which can be made by... [Pg.244]

These conditions are so harsh that they are applicable only to indoles with the most inert substituents. Cyclization can be achieved at much lower temperatures by using alkyllithium reagents as the base. For example, treatment of o-methylpivalanilide with 3 eq. of n-butyllithium at 25 C gives 2-terr-butylindole in 87% yield[2]. These conditions can be used to make... [Pg.27]

The original yams were marketed as silk substitutes for use in apparel, hosiery, lace, home furnishings, ribbons, braids, and in a whole range of fabrics using blends with cotton or wool yams. As the end uses expanded beyond silk replacement, the harsh metallic luster of the yam proved disadvantageous and dull "matt" fibers had to be developed. Oil dulling was invented (11) in 1926, and an improved method using titanium dioxide was developed (12) in 1929. [Pg.345]

Jets for continuous filament textile yam are typically 1 cm diameter gold—platinum ahoy stmctures with 20—500 holes of 50—200 p.m diameter. Tire yam jets are also 1 cm in diameter but typicahy use 1000—2000 holes to give the required balance of filament and yam denier. Staple fiber jets can have as many as 70,000 holes and can be made from a single dome of ahoy or from clusters of the smaller textile or tire yam jets. The precious metal ahoy is one of the few materials that can resist the harsh chemical environment of a rayon machine and yet be ductile enough to be perforated with precision. Glass jets have been used for filament production, and tantalum metal is a low cost but less durable alternative to gold—platinum. [Pg.348]

Pentamethylphosphorotriamide. Of the phosphoramide derivatives, pentamethylphosphorotriamide [10159-46-3] is the most effective finish when appHed to fabric in conjunction with dimethylolmelamine and an amine hydrochloride catalyst. The finished fabric passes the FF3-71 flammabihty test. Its main appHcation is for use on heavyweight clothes since the finish imparts a harsh hand to lightweight fabrics (99). [Pg.490]

Gels. Fluorosihcone fluids with vinyl functionahty can be cured using the platinum catalyst addition reactions. The cure can be controlled such that a gel or a soft, clear, jelly-like form is achieved. Gels with low (12% after 7 d) swell in gasoline fuel are useflil (9) to protect electronics or circuitry from dust, dirt, fuels, and solvents in both hot (up to 150°C) and cold (down to —65° C) environments. Apphcations include automotive, aerospace, and electronic industries, where harsh fuel—solvent conditions exist while performance requirements remain high. [Pg.401]

Electrically conductive mbber (13) can be achieved by incorporation of conductive fillers, eg, use of carbon or metal powders. These mbbers exhibit volume resistivities as low as lO " H-cm. Apphcations include use in dissipation of static charge and in conductive bridging between dissimilar electronic materials under harsh operating conditions. [Pg.401]

Pineapple juice has been available commercially since 1932, but the production and sale of other tropical fmit juices has more recently received significant attention in Europe and, especially, in North America (24). Many tropical fmit juices are too pulpy or have harsh or exotic flavors which make 100% juice products unacceptable to most U.S. consumers. They are more acceptable as nectars containing 25—50% juice or as blended fmit drinks where their strong flavors are diluted or modified. [Pg.574]

The presence of ammonia and hydrogen peroxide in permanent hair color products is a disadvantage. Both are considered by consumers to be harsh chemicals. The odor of ammonia is unpleasant for a personal care product. Monoethanol amine has been used as a substitute for ammonia in some commercial permanent hair color products. It is not as effective as ammonia in allowing the hair to be lightened but it does not have as strong an odor. [Pg.457]

Electric Submersible Oil Well Pump Cable. These cables are rated up to 5 kV and are designed for highly corrosive oil wells that besides oil also contain brine and other harsh chemicals as well as gases under high pressure and high temperatures (6). Insulations can be based on polypropylene for low temperature wells or on ethylene—propylene mbber which is compounded with special ingredients in order to resist the environments of high temperature wells (Fig. 4). [Pg.324]

Goats, the animal of choice in areas of harsh climates and limited food supply, are particularly suited to warm and sometimes arid climates. [Pg.81]

Insulator Walls. Because of the unavailabiUty of electrically insulating materials which can withstand the harsh environment inside coal-fired channels, the insulator walls of the channel are typically made of metal elements which are insulated from each other to prevent any net flow of current. Like electrode walls, insulator walls are designed to operate with a slag coating. [Pg.430]

Fluidized-bed reactor systems put other unique stresses on the VPO catalyst system. The mixing action inside the reactor creates an environment that is too harsh for the mechanical strength of a vanadium phosphoms oxide catalyst, and thus requires that the catalyst be attrition resistant (121,140,141). To achieve this goal, vanadium phosphoms oxide is usually spray dried with coUoidal siUca [7631-86-9] or polysiUcic acid [1343-98-2]. Vanadium phosphoms oxide catalysts made with coUoidal sUica are reported to have a loss of selectivity, while no loss in selectivity is reported for catalysts spray dried with polysUicic acid (140). [Pg.455]

Other biomedical and biological appHcations of mictocapsules continue to be developed. For example, the encapsulation of enzymes continues to attract interest even though loss of enzyme activity due to harshness of the encapsulation protocols used has been a persistent problem (59). The use of mictocapsules in antibody hormone immunoassays has been reviewed (60). The encapsulation of hemoglobin as a ted blood substitute has received much attention because of AIDS and blood transfusions (61). [Pg.324]

Hydrolysis of primary amides cataly2ed by acids or bases is very slow. Even more difficult is the hydrolysis of substituted amides. The dehydration of amides which produces nitriles is of great commercial value (8). Amides can also be reduced to primary and secondary amines using copper chromite catalyst (9) or metallic hydrides (10). The generally unreactive nature of amides makes them attractive for many appHcations where harsh conditions exist, such as high temperature, pressure, and physical shear. [Pg.183]

Good yields of 2,4-diaminoquinolines are obtained through either Lewis acid- or base-induced cyclization of 2-amidinobenzonitriles (20) (58). The method avoids both the harsh conditions and lack of regiospecificity characteristic of earlier preparations. [Pg.392]

Parts made from fluoroelastomers ate used ia appHcations that justify their high cost, usually where the maintenance and replacement costs are high enough to offset the initial cost of the part. These include automotive appHcations such as valve stem seals, fuel injector components, radiator, crankcase and transmission seals, and carburetor needle tips. Numerous seals and gaskets in the marine, oilfield, and chemical processing industries employ fluoroelastomers. In addition, many hoses in the automotive and chemical industry are made entirely of fluoroelastomer compounds or have a veneer of the fluoroelastomer as a barrier exposed to the harsh environment. Seals and gaskets in military appHcations and the binder for flares and missile appHcations ate made with fluoroelastomers. [Pg.234]


See other pages where Harsh is mentioned: [Pg.437]    [Pg.483]    [Pg.503]    [Pg.47]    [Pg.66]    [Pg.230]    [Pg.15]    [Pg.211]    [Pg.114]    [Pg.354]    [Pg.274]    [Pg.371]    [Pg.385]    [Pg.401]    [Pg.562]    [Pg.448]    [Pg.537]    [Pg.532]    [Pg.547]    [Pg.87]    [Pg.316]    [Pg.323]    [Pg.336]    [Pg.242]    [Pg.26]    [Pg.257]    [Pg.144]   
See also in sourсe #XX -- [ Pg.114 ]




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Biological Units Alter Themselves to Protect against Harsh Environments

Environmental change, harsh

Harsh conditions

Harsh environment

Harsh environment electronics

Harsh handle

Harsh reaction conditions

Noise, vibration, and harshness

Noise-vibration-harshness

Stability under Harsh Conditions

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