Numbering of specimens

Number of specimens of each material tested and whether specimens were tested separately or which specimens were tested in the same container... 

In such cases, it is usually preferable to carry out the corrosiontesting program by exposing specimens in operating equipment under actual conditions of service. This procedure has the additional advantages that it is possible to test a large number of specimens at the same time and that little technical supervision is required. 

A sufficient number of specimens should be exposed initially to permit their withdrawal from test in appropriate groups, for example 3 to 5 duplicates after at least three time intervals. For long-time tests, a suitable schedule would call for removals after 1, 2, 5, 10 and 20 years. 

Soil burial tests are popular despite the precautions that are needed. It is also important that a sufficient number of specimens are exposed so that statistical treatment of the results may be applied to compensate for some of the inevitable variations in the exposure conditions. Certain precautions originally set out in 1937 are still valid, and are as follows ... 

A sufficient number of specimens to yield a reliable coverage should be included. 

Outdoor testing is the most accurate method of obtaining a true picture of other resistance. The only drawback of this test is the time required for several years exposure that are usually located in different climatic zones around the world. A large number of specimens are usually required to allow periodic removal and to run representative laboratory tests after exposure. 

The 8 C values of the Preclassic humans at Cuello (Table 2.1) average -12.9 0.9%o (n = 28) in collagen, -9.8 1.0 in bone apatite (n = 16), and -8.7 2.3%o in tooth enamel apatite (n = 33) the S N values in collagen average 8.9 1.0%o (n = 23). The discrepancy in the number of specimens is due to the fact that more teeth were available than post-cranial material, while some of the specimens contained insufficient collagen to measure the nitrogen isotope ratios. Additional bone apatite analyses are in progress. 

Chemical composition or trade name of metals tested Form and metallurgical conditions of specimens Exact size, shape, and area of specimens Treatment used to prepare specimens for test Number of specimens of each material tested and whether specimens were tested separately or which specimens were tested in the same container... 

Information regarding specimens and tasks is stored in two databases. The specimen database contains descriptive information and operating parameters for a number of specimens. The run database contains information regarding the data collection activities that have been performed or that are pending. 

Specified Minimum Tensile Strength Number of Specimens [Note (1)] Energy [Note (2)] Fully Deoxidized Other Than Fully Steels Deoxidized Steels ... 

Population Residue Levels to be Detected. The number of individual specimens required per composite was determined by the MDL values for the different compounds addressed by the broad scan analyses. As indicated previously, a universal MDL of 10 ng was considered to be appropriate for the compounds of interest. The number of individual specimens per composite was chosen so that there was a high probability that an injection drawn from the extract of the composited sample contained an analyte level exceeding 10 ng for each compound in which the population residue levels exceed the stated levels that were of Interest to be detected. The population residue levels of Interest correspond to concentrations expected to be toxic to humans yet are not chosen to be too small to require a very large number of specimens per composite. 

Let X denote the amount of analyte in a tissue sample of mass w grams taken from a randomly selected specimen in the population. The required number of specimens per composite for a particular compound is the minimum value of N satisfying... 

The number of specimens required per composite was the minimum value of N satisfying Equation 1 for all compounds addressed by the broad scan analyses. One constraint on the value of N was that the total mass of the composited sample could not exceed sample preparation and extraction constraints (approximately 30 gram). To actually determine the value of N it was noted that the value of N satisfying Equation 1 depends on the assumed distribution of population residue levels. Various lognormal distributions (i.e. values of the mean and standard deviation) were therefore investigated to determine how N varies with these parameters. 

In addition when it is necessary to process a large number of specimens per day, taking hours over a single specimen is clearly not a practical approach. The use of MRI to examine fresh, unfixed fetal rat and rabbit heads from embryo-fetal development (EFD) studies has already been proposed (6) (see Note 1) and the compromise between image quality and speed of acquisition that is necessary under these circumstances examined. MRI is now considered to have the potential to be an acceptable alternative to current methods after throughput was increased by scanning multiple specimens in parallel with careful optimization of scan parameters. 

Short beam tests provided information on the apparent interlaminar shear strength (ILSS) of laminates made with bare and sized E-glass fibers. In all cases, the specimens failed in shear at or near the midplane, allowing comparisons between fiber types. The ILSS, SD, and number of specimens tested are given in Table 5. 

Group or origin Type (name or number of specimen(s)) Arsenic concentration (mg kg )a Reference(s)... 

Polytype Number of specimens A verage tetrahedral Al A verage Fe/Fe+Mg... 

Syntypes any number of specimens that are collectively the standard. 

Voucher specimens must be prepared, so save enough of the specimens, being certain they contain diagnostic features for positive identification. Vouchers should be deposited in established herbaria if they warrant it. Most herbaria probably would not have space for or desire large numbers of specimens of a single species from one locality or specimens lacking diagnostic characters. We feel it is desirable to keep vouchers for a number of years in case questions should arise about published work. Voucher specimens should be kept dry and insect-free in a special herbarium cabinet, preferably in a herbarium and perhaps at the home institution or in the care of the researcher if they are not appropriate for the herbarium. 

The data of Table 5.6 were by design collected to have a tree type or so-called hierarchical/nested structure. Figure 5.15 shows a diagram of a generic hierarchical structure for balanced cases like the present one, where there are equal numbers of branches leaving all nodes at a given level (there are equal numbers of determinations for each specimen and equal numbers of specimens for each casting). 

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