Agitated tests

The device consists of a low thermal mass test cell of 110 ml volume. This is made of stainless steel with a 0.015-mm wall thickness, but test cells made from other materials can be used. The contents of the cell are mixed using either a magnetically driven stirring bar or a direct drive agitation test cell. The test cell is... 

Foam Properties. A previous paper(1) reported that SAE show better foam breakability than PAE or NPE. This tendency becomes clearer when SAE and PAE having lower carbon number ranges are compared. Figure 9 and Figure 10 show foam volume vs. concentration in an agitation test for C2.2-14 EAE E0 C10-12 AE(9E0) anc PAE(8E0) in the initial stage and after five minutes,... 

Agitation Tests. The observed reaction rate should represent the catalytic kinetics unclouded by phenomena such as the transfer of hydrogen at the gas-liquid interface or reaction species through the stagnant film surrounding the catalyst. 

The minimum stirring rate is usually established from a slnple diagnostic test in which conversion is measured for various levels of agitation. Agitation rate was varied between 500 to 1000 rpm and desulfurization level measured. Results of the agitation tests are listed in Table I. Raising agitation... 

Antirust properties (inhibited mineral oils) NFT 60-151 ISO 7120 ASTM D 665 Spots on a test tube after agitation with oil water... 

If oil and water are mixed as an emulsion, dehydration becomes much more difficult. Emulsions can form as oil-in-water or water-in-oil if mixed production streams are subjected to severe turbulence, as might occur in front of perforations in the borehole. Emulsions can be encouraged to break (or destabilise) using chemicals, heat or just gentle agitation. Chemical destabilisation is the most common method and laboratory tests would normally be conducted to determine the most suitable combination of chemicals. 

Solubility in concentrated sulphuric acid. Place 3 0 ml. of pure concentrated sulphuric acid in a dry test-tube and add 0 -10 g. of a solid or 0 -20 ml. of a liquid. If the compound does not dissolve immediately, agitate for some time but do not heat. Observe any change in colour, charring, evolution of gaseous products, polymerisation accompanied by precipitation etc. 

Quahty control testing of siUcones utilizes a combination of physical and chemical measurements to ensure satisfactory product performance and processibihty. Eor example, in addition to the usual physical properties of cured elastomers, the plasticity of heat-cured mbber and the extmsion rate of TVR elastomers under standard conditions are important to the customer. Where the siUcone appHcation involves surface activity, a use test is frequently the only rehable indicator of performance. Eor example, the performance of an antifoaming agent can be tested by measuring the foam reduction when the sihcone emulsion is added to an agitated standard detergent solution. The product data sheets and technical bulletins from commercial siUcone producers can be consulted for more information. 

Doppler broadening arises from the random thermal agitation of the active systems, each of which, in its own test frame, sees the appHed light field at a different frequency. When averaged over a Maxwellian velocity distribution, ie, assuming noninteracting species in thermal equilibrium, this yields a line width (fwhm) in cm C... 

Precipitation and Purification. During the hydrolysis, control tests are made by turbidimetric titration of samples taken intermittently. When the desired degree of hydrolysis is reached, the ester is precipitated from the reaction solution into water. It is important for the precipitate to have the proper texture for subsequent washing to remove acid and salts for thermal stabilization. Before precipitation, the reaction solution is usually diluted with additional aqueous acetic acid to reduce the viscosity. If a flake texture is desired, the solution is poured into a vigorously stirred, 10—15% aqueous acetic acid. To precipitate the acetate in powder form, dilute acetic acid is added to the stirred reaction solution. In both cases, the precipitated ester is suspended in 25—30% aqueous acid solutions and finally washed with deionized water. The dilution, precipitation temperature, agitation, and strength of the acid media must be controlled to ensure uniform texture. 

Phosphoric acid (wet-process) 28% (20% P20 ), sulfuric acid 20—22%, duoride approx 1—1.5%, probably as hydroduosHicic acid temperature 82—110°C, average 93°C and duration of test 42 days, moderate aeration, agitation by convection only. 

For estimating purposes without tests, a reasonable coefficient for ordinary drying, and without taking the product to absolute diyness, may be assumed at 17 = 50 J/(m s K) for rotaiy agitator diyers and 35 J/(m s K) for rotating units. 

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