Vacuum test

Sample Handling System. Venous or capillary blood, urine, and cerebrospinal fluid are specimens routinely used in medical diagnostic testing. Of these biological fluids, the use of venous blood is by far the most prevalent. Collection devices such as syringes and partial vacuum test tubes, eg, Vacutainer, are used to draw ten milliliters or less of venous blood. At collection time, the test tubes are carefully labeled for later identification. 

Manometric Stability Tests. Based on press measurements developed by gases formed on decompn of ex pis. Am on this group of tests are (1) Brame s Method, (2) Chiaraviglio and Corbino Method, (3) Desmaroux Method, (4) Dupre s-Vacuum Test, (5) Farmer s Vacuum Stability Test, (6) Haid, Becker Dittmar Test, (7) Meerscheidt-Hullassem s Test, (8) Mittasch s Method, (9) Obermuller s Method, and (10) Talliani Test... 

Bottles and vials are not subjected to such a vacuum test because of the flexibility of the rubber closure. However, bottles that are sealed under vacuum may be tested for vacuum by striking the base of the bottle sharply with the heel of the hand to produce a water hammer sound. Another test is the spark test, in which a probe is applied outside the bottle. When it reaches the air space of the bottle, a spark discharge occurs if the headspace is evacuated. 

Davis, Vol 2 (1943) Sensitivity of NG (p 209) Stability Tests for NC, which include Kl-Starch Test at 65.5°, Methyl Violet Test at 134.5°C, Bergmann-Junk and Vacuum Tests (267-69) Testing of Detonators by Nail Test and by US Bureau of Mines Sand Test (421-24)... 

Heat Tests. Under this term may be placed all the stability tests which involve heating an explosive, eg Abel Heat Test, Acidity Measurements (pH measurements), American Test at 65.5° or 80°, Bergmann-Junk Test, Brame s Test, Brunswig s Test, Chiaraviglio Corbino Test, Conductivity Method (De Bruin de Pauw) Continuous Test, Deflagration Test, Desmaroux Test, Dupre s Vacuum Test, Dutch Test,... 

It explodes after 30 hrs in the 100° vacuum test. Deton vel is comparable with RDX. It does not react with dry aluminum at 90°... 

Bottle closure properly closed (torque force, vacuum test)... 

Sauer (Ref 9) stabilized Dinitrodiaminomethane at a temp below its mp by coating with 0.1 to 2.0% polynitrophenol or polynitro aromatic carboxylic acid by means of absorption, recrystn or evapn from a non solvent. Thus, 98% of the pure compd 8C 2% Picric Acid were mixed 8t benz added to form a slurry. After the mixt was dried under vacuum, tests at 75° showed improved stabi-... 

O2NO).CH.CHj.N(N02) mw 251.12, N 27.89% OB to C02 minus 15-9% solid mp 112—113° was prepd by nitrating with fuming nitric acid in the presence of acetic anhydride at below 15°, the product obtd by condensing (on heating) urea, C0(NH2)2. with 1,3-di amino-2-propanol, H2N.CH2.CH(OH).CH2.NH2. It is a very powerful expl (Trauzl Test Value = 135% PA), comparable in Impact Sensitivity to Tetryl (FI Value = 60% PA), but of unsatisfactory Thermal Stability (99° Heat Test 3 minutes 100° Vacuum Test — more than 15cc in less than 16 hrs). It is hydrolyzed by water. See Refs 2 3 Refs 1) A.H. Blatt, OSRD Rept 2014(1944) 2) A.F. McKay D.F. Manchester, JACS 71, 1972(1949) CA 43, 9065(1949) 3) A.F. 

Figure 11.7. Two types of laboratory filter arrangements, (a) Vacuum test filter arrangement standard sizes are 0.1, 0.05, or 0.025 sqft (Dahlstrom and Silverblatt, 1977). (b) Laboratory pressure filter with a vertical filtering surface and a mechanical agitator mild air agitation may be preferred (Bosley, 1977).

Incompatibility may result in a loss of effectiveness or may be very hazardous. For example, -> Chlorate Explosives and -> Ammonium Nitrate Explosives are not compatible (formation of self-decomposing ammonium chlorate). For compatibility testing - Vacuum Test. 

The vacuum test is used for compatibility testing and applied as a so-called reactivity test. The compatibility between the explosive and the contact material (adhesive, varnish, etc.) is tested by determining the gases liberated by the explosive alone, by the contact material alone, and by the two together. The measure of compatibility (reactivity) is the difference between the sum of the gas volume liberated by each component separately and the gas volume obtained after storing the explosive and the contact material together. If this difference is between 3 and 5 ml, the compatibility is considered un-certain" above 5 ml, the two materials are incompatible. 

A survey of European Space Tribology Laboratory vacuum testing on satellite slip-rings reported that slip-rings designed for satellite solar-array mechanisms had operated satisfactorily over long periods with a variety of Ag/Cu/MoSj compacts . The relationship between brush wear rate and molybdenum disulphide content is shown in Figure 12.5 for some hot-pressed composites in silver with 1% of copper. 

The vacuum test ensures that the sterilization operation does not adversely affect the waterproof status of the freeze dryer. 

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