Physical tests density

Testing. Chemical analyses are done on all manufactured abrasives, as well as physical tests such as sieve analyses, specific gravity, impact strength, and loose poured density (a rough measure of particle shape). Special abrasives such as sintered sol—gel aluminas require more sophisticated tests such as electron microscope measurement of a-alumina crystal si2e, and indentation microhardness. 

In the United States, a number of physical tests are performed on siUcon carbide using standard AGA-approved methods, including particle size (sieve) analysis, bulk density, capillarity (wettabiUty), friabiUty, and sedimentation. Specifications for particle size depend on the use for example, coated abrasive requirements (134) are different from the requirements for general industrial abrasives. In Europe and Japan, requirements are again set by ISO and JSA, respectively. Standards for industrial grain are approximately the same as in the United States, but sizing standards are different for both coated abrasives and powders. 

W) C. Belgrano, "Gli Esplosivi , U. Hoepli, Milano (1952), pp 15 to 53 (Physical tests for mining explosives. Included are density, stability, Trauzl test, detonation velocity, Hess test, crusher test, sympathetic detonation test, sensitiveness to initiation, sensitiveness to impact, steel plate test and explosion temperature determination) pp 73 to 75 (Analysis of NG) 76 to 84... 

Current tests are generally destructive (i.e., sample is altered or destroyed) and robust estimates of measurement system variability (all aspects of the procedure including the operators) are difficult to obtain without using methods such as Gauge R R-reproducibility and repeatability (14). Suitability of current methods then is based on calibration using a calibrator system that has its own built-in variability and other assumptions (e.g., in physical testing such characteristics as size, shape, density can alter aerodynamic and/or hydrodynamic behavior of materials in a test system and contribute to systems variability). 

S.P. Howell J.E. Tiffany, "Methods for Routine Work in the Explosives Physical Laboratory of the Bureau of Mines , USBurMines Technical Paper 186, Wash, DC (1918), 14-15 (Detn of apparent specific gravity by sand method) 4) C.E. Munroe J.E. Tiffany, "Physical Testing of Explosives , USBurMines Bull 346, Wash, DC (1931), 22-3 (Detn of apparent sp gr by sand test) 24 (Detn of shaking density) 5) Vennin, Burlot Lecorche" (1932), 154 (Gravimetric apparent density) 6) Pepin Lehalleur (1935), 41, 54 62 (Densite de enlargement) 99-100 (Densimeters of Bianchi and of Bode) 7) Hayes (1938), 50 (Loading density)... 

BS 903 PA1 Physical testing of rubber part A1 Determination of density... 

Physical tests for Identification. Specific density, index of refraction, color, viscosity, and melting point tests are used to identify fats and oils. The onset, flow point, and the temperature range over which melting occurs are indicative of specific numbers in fats. They are determined by standardized procedures. 

These mixtures were mechanically blended for 10 seconds at room temperature and poured rapidly into a wooden mold (14" x 6" x 4") and allowed to expand freely at room temperature. After approximately 10 to 15 minutes, the resultant foam was very rigid, posessing fine cells. The residual solvent was removed from the resultant foam by placing it in a lOO C oven for 4 days. The foam had the following physical properties density, 2.82 pcf compressive strength (parallel to rise), 30.2 psi and flame test (ASTM D 1692), total length burned, 0.1 inch. 

Although modern counterfeiters have mastered the duplication of the outside appearance of precious metals, some simple chemical/physical testing can determine their authenticity. Consult a reference book and determine the densities of gold, silver, copper, lead, iron, nickel, and zinc. 

Physical test data support the IR findings. Tensile strength, elongation and equilibrium moduli are tabulated in Table VI. All of the physical properties examined are indicators of crosslink density and can reflect differences in cure. Table VI shows that these physical properties are essentially equivalent for stabilized and unstabilized films. 

Mass, density, and dimensions have been grouped together largely for convenience, but there is an obvious connection between them in that density can be derived from a knowledge of dimensions and mass. They are also measurements used as essential parts of other physical tests. For example, density is used to calculate volume loss in an abrasion test, mass is an intrinsic factor in water absorption tests, and there are very few tests that do not in some way involve the measurement of dimensions. 

Other geometrical and physical tests on the aggregates of the RA (angularity, resistance to fragmentation, resistance to polishing polished stone value [PSV], resistance to surface abrasion aggregate abrasion value [AAV], particle density, water absorption, etc.) may also be necessary to be determined when comprehensive mix design is followed. 

Physical tests including pH, relative density, optical rotation, refractive index, conductivity, viscosity and osmolality are generally used as in-process controls or as simple laboratory tests for the finished product. 

There are other tests for polymers that are not included in this review including some density, filler analysis techniques and other physical tests. For convenience, a listing of ASTM and ISO standards for the major test in this work is provided in the references. 

Receiving Inspection. Many types of tests have been devised for testing raw materials. Depending upon the severity of the need for inspection, the types of tests selected may vary from being basic and simple to sophisticated and complex. Some of the most common basic tests are the melt index test, specific gravity, bulk density, spiral flow test, and viscosity tests. Gel permeation chromatography, infrared analysis, thermal analysis, and rheometry are some of the more elaborate raw material quality control tests. These tests are discussed in detail in Chapter 7. Some processors also choose to mold test bars from a small sample of raw material and conduct physical tests such as tensile, impact, and flexural tests and then evaluate the results to see if they meet the preestablished specifications. 

Composition is normally expressed by a distillation curve, and can be supplemented by compositional analyses such as those for aromatics content. Some physical properties such as density or vapor pressure are often added. The degree of purity is indicated by color or other appropriate test (copper strip corrosion, for example). 

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