Material standards

The reactor effluent, containing 1—2% hydrazine, ammonia, sodium chloride, and water, is preheated and sent to the ammonia recovery system, which consists of two columns. In the first column, ammonia goes overhead under pressure and recycles to the anhydrous ammonia storage tank. In the second column, some water and final traces of ammonia are removed overhead. The bottoms from this column, consisting of water, sodium chloride, and hydrazine, are sent to an evaporating crystallizer where sodium chloride (and the slight excess of sodium hydroxide) is removed from the system as a soHd. Vapors from the crystallizer flow to the hydrate column where water is removed overhead. The bottom stream from this column is close to the hydrazine—water azeotrope composition. Standard materials of constmction may be used for handling chlorine, caustic, and sodium hypochlorite. For all surfaces in contact with hydrazine, however, the preferred material of constmction is 304 L stainless steel. 

Standards Engineering Standards Engineering Society 6700 Penn Avenue South Minneapolis, Minn. 55423 A bimonthly in which general news and technical articles dealing with all aspects of standards and U.S. and foreign articles on standard materials and caUbration and measurement standards are presented. 

Material ASTM standard Material ASTM standard... 

During 1974—1985, about 200 sulfur—asphalt roads were constmcted worldwide, half of which were ia the United States. AH U.S. SEA experimental sections designed and constmcted according to standard practices usiag standard materials are performing as well as the control sections of conventional asphalt ia these experimental projects (49). 

Shipment and Storage. Much of the trichloromethanesulfenyl chloride produced is used captively. However, it can be shipped in dmms. Standard materials for storage and handling are nickel. Monel, and glass. Trichloromethanesulfenyl chloride is not corrosive to nickel and Monel when dry, but cate must be taken to prevent its contact with moisture. 

Because carbon is difficult to machine, very tittle impervious carbon equipment is made. However, impervious graphite has been accepted as a standard material of constmction by the chemical process industry for the fabrication of process equipment, such as heat exchangers, pumps, valves, towers, pipe, and fittings (9,10). 

V. L. Anderson and R. A. McLean, Design of Experiments—A Eea/istic Approach, Marcel Dekker, New York, 1974. This book provides an extensive exposition of experimental design at a relatively elementary level. It includes most of the standard material, as well as detailed discussions of such subjects as nested and spHt-plot experiments. Restrictions on randomization receive special emphasis. 

In this chapter we define what is meant by a shock-wave equation of state, and how it is related to other types of equations of state. We also discuss the properties of shock-compressed matter on a microscopic scale, as well as discuss how shock-wave properties are measured. Shock data for standard materials are presented. The effects of phase changes are discussed, the measurements of shock temperatures, and sound velocities of shock materials are also described. We also describe the application of shock-compression data for porous media. 

Figure 4.3. Shock velocity versus particle velocity for several standard materials.

Figure 4.4, Shock pressure versus specific volume for several standard materials.

Figure 4.5. Shock pressure versus particle velocity for various standard materials.

Standard materials are chosen to resist ordinary corrosion of steam and water. If corrosive vapors or liquids are involved, state under special material customer has found best for his operation. Is export packing required ... 

Standard materials for the compressor are cast iron for the cylinder and carbon steel for the shaft. The rotor parts are steel. The liquid pistf f compressor has another feature that compensates for low efficiency, using special materials of construction and compatible liquid compr sant, unusual or difficult gases may be compressed. By using titanium internal materials and water as a compressant, gases containing wet chlorine can be compressed. This is a very difficult application for most o( the other compressor types. 

A commonly used form of internal modulation is differential reflectometry, in which the reflectance of the sample under investigation (or a portion of it) is compared to a standard material. This can be accomplished either by holding the sample stationary and scanning the probe beam between two regions or by holding the l t spot fixed and moving the sample. ... 

The precise impact experiment offers both versatility and the highest of precision. In typical experiments, the projectile is faced with an impactor that is either the same material as the sample to be impacted or a standard material whose properties are known and reproducible. In a symmetric impact configuration the impactor and sample are the same upon impact, precisely one-half of the impact velocity is imparted to the sample. As the impact velocity can be readily measured to an accuracy of 0.1%, this condition provides the most accurately known and best characterized condition achieved in shock-compression science. 

The ramp of pressure to about 3 GPa observed in shock-loaded fused quartz has been used very effectively in acceleration-pulse loading studies of viscoelastic responses of polymers by Schuler and co-workers. The loading rates obtained at various thicknesses of fused quartz have been accurately characterized and data are summarized in Fig. 3.6. At higher peak pressures there are no precise standard materials to produce ramp loadings, but materials such as the ceramic pyroceram have been effectively employed. (See the description of the piezoelectric polymer in Chap. 5.)... 

The piezoelectric behavior of both quartz and lithium niobate has been studied in a series of careful, systematic investigations. (See Graham and coworkers [65G01, 70101, 75G04].) The experimental arrangement is shown Fig. 4.2. The impactor, preferably the same material as the piezoelectric sample (but perhaps another standard material), is accelerated to a preselected... 

Fig. 5.6. Typical current-time responses from impact-loaded PVDF are shown for samples on the standard materials indicated. In each record the upper traces are the full record showing short duration negative and positive current pulses due to loading and release in the standard. Time increases from left to right. The detail of each pulse depends upon the shock impedance of the materials. In each record, enlarged views of loading and release pulses are shown.

When the materials handled are noncorrosive, the flame arrester vendor s standard materials of constrnction for the honsing and arrester element are commonly nsed. For noncorrosive service honsings are normally available in alnminnm, carbon steel, dnctile iron, and 316 stainless steel the elements are commonly available in alnminnm or 316 stainless steel. 

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