In Repeatability

The criterion retained up to now in the specifications is not the true vapor pressure, but an associated value called the Reid vapor pressure, RVP. The procedure is to measure the relative pressure developed by the vapors from a sample of motor fuel put in a metallic cylinder at a temperature of 37.8°C. The variations characteristic of the standard method are around 15 millibar in repeatability and 25 millibar in reproducibility. 

The final error of the zlRlOO is on the order of one point in repeatability. 

Repeatability. This refers to two aspects of inspection similarity between objects that are inspected and possibility of maintaining constant inspection conditions (settings) for all the inspections performed. Obviously, interpretation of data in repeatable conditions is significantly simplified. Usually, inspection during or after manufacturing process will be repeatable. Another example of repeatable inspection is inspection of heat exchangers in power nuclear plants, inspection of aircrafts as these are well standardised. However, a large part of the NDT inspection done is not repeatable. 

Neural network classifiers. The neural network or other statistical classifiers impose strong requirements on the data and the inspection, however, when these are fulfilled then good fully automatic classification systems can be developed within a short period of time. This is for example the case if the inspection is a part of a manufacturing process, where the inspected pieces and the possible defect mechanisms are well known and the whole NDT inspection is done in repeatable conditions. In such cases it is possible to collect (or manufacture) as set of defect pieces, which can be used to obtain a training set. There are some commercially available tools (like ICEPAK [Chan, et al., 1988]) which can construct classifiers without any a-priori information, based only on the training sets of data. One has, however, always to remember about the limitations of this technique, otherwise serious misclassifications may go unnoticed. 

All the work is mechanised with an assigned scanning density, this allowing comparison of the UT results in repeated diagnostics of the constructions. Mechanical scanning practically eliminates overlooking of metal defects. Interpretation of the... 

Replicate Analyses. Confidence in the test result is improved by reducing the measurement variabihty. This variabihty in repeat analyses is known as precision. One method to improve the precision of the measurement is to perform complete rephcate analyses of the same sample beginning with the sample preparation (26). This is appropriate when the sample is known to be representative of the material sampled. When this is not the case, multiple samples should be taken for analysis. 

When exposed to heat, cotton fabrics, like most substances, increase in temperature to an extent that is proportional to their specific heats. Altering the chemical composition of the fabrics such that large amounts of heat are absorbed and released in repeatable cycles of controllable temperature ranges produces fabrics that are described as temperature adaptable. The process insolubili2es poly(ethylene glycol)s cross-linked with methylolamides in the cotton fabric (78). As with flame-retardant cellulose, attachment is through an ether linkage to the cellulose at a relatively low DS. 

L-asparaginase therapy with an extra-corporeal device in patients with malignant lymphoma has resulted in repeated remissions of metastases (242). This technique utilizes L-asparaginase covalentiy bound to the surface of a battery of plates contained in a portable chamber which has been inserted between an artery and vein. 

Figure 14.10 A muscle viewed under the microscope is seen to contain many myofibrils that show a cross-striated appearance of alternating light and darkbands, arranged in repeating units called sarcomeres. The dark bands comprise myosin filaments and are interupted by M (middle) lines, which link adjacent myosin filaments to each other.

Chordal Action. The chordal rise and fall of each chain pitch as it contacts a sprocket tooth is known as chordal action and results in repeated variations in linear chain speed. As shown in Figure 3-39, the amount of chordal movement and chain-speed variation becomes progressively smaller as the number of teeth in the pinion is increased. Smoother operation and longer chain life may be obtained by selecting pinions with 21 teeth or more because chain-joint articulation is reduced. Chordal action becomes negligible when a sprocket has 25 teeth or more. 

We attempted to prepare Pu(V) stabilized as K2PUF7, Rb2PuF7, and CsPuFg, but were only successful in repeating the preparation of CsPuFt ( 1). Since there is a paucity of information concerning syntheses of this sort, we cite possible grounds for our unsuccessful as well as our successful efforts. 

The mechanisms by which Pu(IV) is oxidized in aquatic environments is not entirely clear. At Oak Ridge, laboratory experiments have shown that oxidation occurs when small volumes of unhydrolyzed Pu(IV) species (i.e., Pu(IV) in strong acid solution as a citric acid complex or in 45 percent Na2Coj) are added to large volumes of neutral-to-alkaline solutions(23). In repeated experiments, the ratios of oxidized to reduced species were not reproducible after dilution/hydrolysis, nor did the ratios of the oxidation states come to any equilibrium concentrations after two months of observation. These results indicate that rapid oxidation probably occurs at some step in the hydrolysis of reduced plutonium, but that this oxidation was not experimentally controllable. The subsequent failure of the various experimental solutions to converge to similar high ratios of Pu(V+VI)/Pu(III+IV) demonstrated that the rate of oxidation is extremely slow after Pu(IV) hydrolysis reactions are complete. 

Increased creatine and PCr concentrations have been achieved by giving creatine orally. The creatine dose used was 20 g daily for 4—5 days, administered in repeated 5 g doses. Muscle creatine increased by 20-40% above the preadministration content and the PCr increased by 8-15% (Harris et al., 1992). Torque generation by the knee extensor muscles was measured during five repeated bouts of 30 isokinetic MVCs, with 2 min rest periods between bouts. The exercise protocol was performed four times, before and after placebo or creatine supplementation. The total peak torque production increased significantly in all five bouts of maximal... 

Water scarcity is a structural, persistent drought affecting resources and aquatic ecosystems, with implications in water quality and societal needs. Scarcity results in repeated drought episodes. While drought is a temporary (and often normally associated to climatic patterns) decrease in water resources, water scarcity occurs when water demand exceeds the water resources exploitable under sustainable conditions. 

Tropoelastin is the soluble precursor of elastin and consists of alternating hydrophobic and hydrophilic peptide domains. The most common amino acids in the hydrophobic domains are Gly, Val, Ala, and Pro, which are often present in repeats of tetra-, penta-, and hexapeptides, such as Gly-Gly-Val-Pro, Gly-Val-Gly-Val-Pro, Gly-Val-Pro-Gly-Val, and Gly-Val-Gly-Val-Ala-Pro, respectively [3, 4]. The hydrophilic domains are mainly composed of lysines interspersed by alanines. 

It is now known that each codon consists of a sequence of three nucleotides ie, it is a triplet code (see Table 38—1). The deciphering of the genetic code depended heavily on the chemical synthesis of nucleotide polymers, particularly triplets in repeated sequence. 

Monster AC, Boersma G, Duba WC. 1979. Kinetics of trichloroethylene in repeated exposure of volunteers. Int Arch Occup Environ Health 42 283-292. 

Unidimensional multiple development consists in repeated developments of the same plate with the solvent for the same distance and in the same direction. After each... 

Chitwood (2) found that copper compounds exhibited only a short period of maximum catalytic activity for the dehydrogenation of ethanolamine to glycine salt. In this study, the catalytic activity of a skeletal copper catalyst was tested in repeated use. The catalyst used was prepared by selectively leaching CuAl2 particles in a 6.1 M NaOH solution at 293 K for 24 hours. Figure 1 shows the profiles of hydrogen evolved versus reaction time. 

Clearly the rate of reaction declines in repeated cycles. However the decrease between cycle 2 and cycle 3 was considerably smaller than that between cycle 1 and cycle 2, indicating that loss of activity occurred primarily in the first cycle. This is due to loss of surface area as discussed later. 

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