Variety of Tests

The sensitivity of azides to the impact of the falling hammer or weight, or to collisions with other massive objects, is among the properties commonly determined when a compound or artifact is fust prepared [5,8]. A crude impact test is easy to devise, but it is only one of several tests that assess the effect of comparatively weak mechanical action on explosives (the effect of strong shocks 

A brief description of representative apparatus follows. Test results on lead azide are available for all these machines for analysis later in this chapter. 

The weight is raised to a given height and allowed to drop on the plunger. If 

Two laboratories that use this apparatus are the U.S. Bureau of Mines at Bruceton, Pennsylvania, and Picatinny Arsenal, Dover. New Jersey. The apparatus at the Bureau of Mines has been instrumented [13] with the addition of a foree gauge and a reaction detector, which make it possible to examine the force exerted on the sample and to make estimates of the reaction times. 

The weight is dropped from heights up to 320 cm and is usually 2.5 kg although 2- and 5-kg weights are alternatives. The 35-mg sample rests as a loose pile in the center of a 1-in.-square piece of sandpaper, placed on a hardened steel anvil, 1.250 in. diam. The 1.25-in.-diam striker rests on the explosive and slides freely within a guide. A noisemeter, an audiovisual instrument, is used to assist the operator in his judgment [4]. 

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Milk and its products can be subjected to a variety of tests to determine composition, microbial quaUty, adequacy of pasteurization, contamination with antibiotics and pesticides (qv), and radioactivity (18). 

Plastics testing encompasses the entire range of polymeric material characterizations, from chemical stmcture to material response to environmental effects. Whether the analysis or property testing is for quaUty control of a specific lot of plastic or for the determination of the material s response to long-term stress, a variety of test techniques is available for the researcher. 

Golorfastness. A variety of test methods exist for determining the fastness, or color retention, properties of dyed fabric exposed to various conditions of weathering, laundering, or general exposure associated with the end use of the product. The AATCC Technical Manual should be consulted... 

EmulsffiedAsphalts (ASTMD244). This standard covers a variety of tests for the composition, handling, nature and classification, storage, use, and specifying of asphalt emulsions used primarily for paving purposes. 

Dynamometer and Vehicle Testing. Friction materials are evaluated in the laboratory by a great variety of tests and equipment. 

Although a variety of test methods, eg, Dk, modulus, and tear strength, exist to determine key properties of potential contact lens materials, a number of properties, eg, wettabihty and deposition, have no predictive methodology short of actual clinical experience. 

Ethylene oxide has been shown to produce mutagenic and cytogenic effects in a variety of test systems (226). An increased frequency of chromosomal aberrations in peripheral lymphocytes of monkey exposed to ethylene oxide for 104 weeks has been reported (240). In mice, it is an effective inducer of chromosome breaks leading to dominant-lethal mutations. In addition, ethylene oxide has been shown to induce heritable effects in the heritable translocation test conducted in mice exposed to ethylene oxide by inhalation (241,242). In this study, male mice were exposed to ethylene oxide ranging from 165 to 300 ppm for 6 h per day 5 or 7 days/week for 8.5 weeks. Ethylene oxide has also been shown to bind to proteins (243) as well as to DNA (244). Several studies on ethylene oxide-exposed workers have demonstrated an increased incidence of chromosomal aberrations and sister chromatid exchanges the relevance of such effects to human health evaluation is currendy uncertain. 

A variety of test procedures and use guidehnes have been developed. In addition, companies or associations may develop internal standards. The Federal Register, 33 CFR, Part 154, contains the USCG requirements for detonation arresters in marine vapor control... 

A wide variety of tests may be useful in assessing the long term fate of a solidified product. An appropriate... 

In the majority of cases, the tests are conducted using a dead-weight lever-arm stress-rupture rig with an electric timer to determine the moment of fracture, but a variety of test rigs similar to those shown in Fig. 8.89g are also used. The evaluation of embrittlement may be based on a delayed-failure diagram in which the applied nominal stress versus time to failure is plotted (Fig. 8.103) or the specimen may be stressed to a predetermined value (say 75% of the ultimate notched tensile strength) and is considered not to be embrittled if it shows no evidence of cracking within a predetermined time (say 500 h). Troiano considers that the nature of delayed fracture failure can be described by four parameters (see Fig. 8.103) ... 

There is a seemingly infinite variety of tests for specific applications, and some even have alternate adaptations for particular industries or customers. This section contains a few examples of common application tests for urethane foams, coatings, adhesives, and elastomers that may be conducted in addition to those described above. Some of these are just specialized versions of tests discussed in die previous section but are presented here because they have been developed for specific applications. Others are more broadly useful and very common. 

However, use of the loss tangent in Eq. (13) is an oversimplification. Instead, we shall make use of an empirical dissipation law obtained in the study of rate-dependent adhesion of elastomers (19). Maugis and Barquins [19], in order to explain the dynamic adhesion of elastomers in a variety of test configurations (peel, flat punch, etc), proposed the following relation ... 

The variety of test data sets has helped to broaden our understanding of how different methods perform under a variety of circumstances. Notably, the enrichment... 

It may be fairly simple in principle to build an ES in areas such as analytical chemistry, in which most conditions and actions are clear-cut, but matters are not always so straightforward. A doctor uses a variety of tests and questions to determine what illness might be responsible for a patient s symptoms. While some of the data on which a doctor relies will... 

Kidney function is determined through a variety of tests that measure the chemical content and quantity of urine. For early kidney damage proteins or sugars are found in the urine. Liver function is determined through a variety of chemical tests on the blood and urine. 

The group of Byron and co-workers established an IPL model specifically to study drug deposition and absorption [14], and reported a novel technique for drug administration [15] and described the absorption of a variety of test compounds. The studies conducted in this model have been reviewed recently, along with a pharmacokinetic model developed to describe the disposition of the drugs administered via this route [119],... 

For the measuremeut of other petroleum products, a wide variety of tests are available, lu fact, approximately 350 tests (ASTM, 2000) are used to determiue the differeut properties of petroleum products. Fach test has its owu limits of accuracy aud precisiou that must be adhered to if the data are to be accepted. 

Oxygen is one of the five (C, H, N, O, and S) major elements in resids and asphalt, although the level rarely exceeds 1.5% by weight. Many petroleum products do not specify a particular oxygen content, but if the oxygen compounds are present as acidic compounds such a phenols (Ar-OH) and naphthenic acids (cycloalkyl-COOH), they are controlled in different specifications by a variety of tests. 

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