Larger scale testing

Flame Resistance. Traditionally, small-scale laboratory flammabiUty tests have been used to initially characterize foams (38). However, these do not reflect the performance of such materials in bulk form. Fire characteristics of thermal insulations for building appHcations are generally reported in the form of quaHtative or semiquantitative results from ASTM E84 or similar tunnel tests (39). Similar larger scale tests are used for aircraft and marine appHcations. 

A thermal scan showed that the exotherm of the principal reaction can be significant if the system is neither controlled nor vented. From isothermal studies (i.e., experiments at constant temperature), time-to-maximum rate was determined which was comparable to that obtained from the DCS data. The larger scale data showed, not surprisingly, more rapid reactions at elevated temperatures. Thus, it was decided to use the DSC data at lower temperatures, and the larger scale test data at higher temperatures for hazard evaluation. 

A few larger-scale tests were planned wherein a larger mass of water would be driven into a mass of molten NaCl. All tests were negative and photography showed that a few leading drops of water would always contact the salt, explosively boil, and drive the descending water column back so as to prevent it from contacting the salt ... 

Larger Scale Testing. The standard card gap test (2) is test No. 1 of a series of larger scale tests designed to determine the sensitivity of liquid propellants to hydrodynamic shock. In this test, relative sensitivities of various propellants are determined in terms of the number of 0.01-inch thick cellulose acetate cards required to attenuate a standard shock sufficiently just to prevent initiation in the test sample. When performed according to the exacting conditions of apparatus and procedure, the results are very reproducible from one laboratory to another. However, small variations in the apparatus or procedure can cause major variations in the resulting data, and therefore the test can be considered only relative. A major drawback of the standard test is that it cannot accommodate materials that are volatile under the test condition. At TCC-RMD some special equipment has been developed that allows tests to be made on confined samples at elevated temperature and pressure. 

Chloro-2-thenyl-tri- -butylphosphonium Chloride. Quite active in screening tests and in small-sized plot tests, this plant growth regulant (13) did not show suflBcient activity in larger-scale tests to remain an active product candidate. 

The second, more empirical path, is marked by the development of larger scale test methods that are meant to simulate potential "real world" or actual exposure conditions. Examples of such test methods are room fire tests in which actual pieces of furniture are placed in 8 x8 xl2 room-size enclosures and exposed to fire sources ranging from multiple sheets of newspaper or waste baskets in full conflagration to even larger sources such as 20 lb. and 25 lb. wood cribs. 

Larger Scale Testing of Inhibitors in Transfer Moulding Resins. 

Further experiments are, therefore, required before it can be stated definitely that the methyl group of the methyl bromide is present in the final alkylate. The desired information might be obtained by carrying out larger scale tests with more accurate analysis of all of the products. It would almost certainly be obtained from experiments employing methyl bromide containing radioactive carbon. If mcthylation of the butane predominates, the isopentane will be radioactive if reduction of the type shown above occurs, the radioactive carbon will be found in the methane. 

Current work on BMTl was reported. From the results, one can see that the dual relative permeability - saturation model used in the desaturation example might be useful for larger scale tests, such as the BMTl application, so that desaturation near the heater can be reproduced correctly by the TH model. 

Larger scale tests, to determine the effect of sample size on decay at high relative humidity, were made in small completely jacketed rooms, used without internal forced air circulation. During tests, the relative humidity in the open space was 97-99%... 

Preliminary small scale combustion tests carried out with the pyrolysis oil as produced (20% water content) showed that it burns readily in a furnace with a conventional pressure atomizing burner, providing the combustion box is preheated. If an air atomizing nozzle is used with a pilot flame, no pre-heating of the combustion chamber is necessary. Larger scale tests for extended periods have not yet been done, but preliminary work shows that the pyrolysis oil has potential as a substitute fuel oil. 

The micro-reactor studies progressed in tandem with testing in a small pilot plant that was constructed to allow evaluation of formed catalysts that could be used in a commercial reactor, instead of the pressed powders tested in the micro-reactors. This larger scale testing was carried out in a 1" internal diameter reactor (120 ml cat.) fitted with a 5 zone heating system to ensure more isothermal operation and typically allowed 1-3 mm particles to be evaluated. The reactor tube internals were configured in such a way as to minimise the radial temperature profile and ensme that the reactor operated in a thermally stable regime. 

Bulk samples are collected mainly for larger-scale tests, to check swelling the properties of various coal seams, to rank coal as high pressure coal and low pressure coal. 

Two basic methods of approach can be undertaken to determine the suitability of a coal or coking blend (1) indirect coking pressure measurements at laboratory scale and (2) direct coking pressure measurements by larger-scale tests, using a few hundreds of kilograms of coal while trying to reproduce industrial conditions. 

The availabihty of a pool of qualified consumers also allows for testing in a typical use situation such as a home-use test This capability enhances the value of a sensory capability. Here too its goal is to provide support for a product before larger scale testing. 

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