Elimination variation

Milling not only provides intimate mixing, but also eliminates variation in ribbon thickness and cmshes lumpy materials, eg, overdried soap, which might impact finished bar texture. Milling is also used for the formation of the proper bar soap crystalline phase, which plays a critical role in both the performance properties of the soap bar and the handling characteristics of the in-process soap. For example, too hot a milling temperature can create sticky soap that is difficult to process further. 

Fluoride. A fluoride concentration of ca 1 mg/L is helpful in preventing dental caries. Eluoride is deterrnined potentiometrically with an ion-selective electrode. A buffer solution of high total ionic strength is added to the solution to eliminate variations in sample ionic strength and to maintain the sample at pH 5—8, the optimum range for measurement. (Cyclohexylenedinitrilo)tetraacetic acid (CDTA) is usually added to the buffer solution to complex aluminum and thereby prevent its interference. If fluoroborate ion is present, the sample should be distilled from a concentrated sulfuric acid solution to hydrolyze the fluoroborate to free fluoride prior to the electrode measurement (26,27). 

Vehicle tests are considered the ultimate in friction material evaluation, but to be accurate these tests must be carefully designed to eliminate variations caused by changing conditions. ControUed-temperature tests and parallel-test controlled vehicles normally perform the function satisfactorily but at increased cost. 

More uniform results may be expected if a substantial layer of metal is removed from the specimens to eliminate variations in condition of the original metallic surface. This can be done by chemical treatment (pickling), electrolytic removal, or grinding with a coarse abrasive paper or cloth, such as No. 50, using care not to work-harden the surface. At least 2.5 x 10 mm (0.0001 in) or 1.5 to 2.3 mg/cm (10 to... 

Automatic injectors, which eliminate variations due to the analyst, improving reproducibility, and which can be controlled by computer, are of value where large numbers of samples are to be analysed or unattended operation is required. Samples and standards loaded into racks or turntables can be run in a predetermined sequence and under different operating conditions. Such devices can also be used for single samples to improve injection precision. 

The quality of differential staining will determine the ease and accuracy of SCE scoring, and, to eliminate variation, results from different observers should occasionally be compared. Furthermore, to avoid observer bias, scorers should have slides from different treatment groups equally distributed among them, as with all cytogenetic studies. 

In our NMR studies 143,147,148,322-324) of amine and other adducts of Ni[R-dtp]2 complexes neat amines were employed in order to eliminate variations in extent of association (H-bonding) of the amines, to permit observation of NH proton shifts, and to maximize the concentration of the preferred adduct. The use of high concentration of primary amines in solutions with Ni[R-dtp]2 complexes can lead to products other than those expected, e.g., with aliphatic diamines, the R-dtp anion salts of f/zs(diamine)nickel(ll) chelates are obtained ). Furlani and co-workers ) have shown that Ni-(ethyl-dtp)2 reacts with n-butyl amine to yield complexes containing the NiS2N4 chromophore, presumably with monodentate ethyl-dtp. In all work with adducts it is necessary to assure that the complexes, adduct molecules and solvent systems are anhydrous. A number of authors 132,284,295,329) shown that Ni[ R-dtp ]2 complexes decompose when in contact with water. 

To eliminate variations in urinary excretion of GAGs, the results are referred to creatinine content of the sample. As an alternative to measuring the increase of absorption at 520 nm, the assessment of decreased absorption at 596 nm may be advantageous [61]. 

Setting reasonable specifications depends on the development of reliable test procedures and well-characterized reference materials for method development. Statistical control processes can be used to eliminate variations to reduce off-specification catalysts and contractual disputes. 

A 6 month inhalation study was conducted in rats in which the animals were exposed daily to 10 mg m At 3 months, neuromuscular depression, lymphopenia, neutrophilia, and decreased oxygen consumption were observed. In the fifth month, increased organic sulfate elimination, variation in weight, arterial pressure, liver function, and protein metabolism were observed. Liver damage was reported upon histological examination. Studies on the teratogenic, embryotoxic, and cytogenic effects of 2-ME have been inconclusive. 

High-throughput experimentation has been applied for the evaluation of the responses of different-size CdSe nanocrystals incorporated in a variety of rationally selected polymer matrices. Automation of these experiments not only speeds up the screening process of candidate sensing materials, but also importantly reduces or eliminates variation sources that otherwise affect response of the sensing materials if measurements are done manually. 

All the automatic systems of analysis that have so far gained acceptance in clinical laboratories, or have been projected, include a device for the successive, mechanical measurement of samples in a batch, and these systems have substantially eliminated variations in volume of sample taken from different specimens. In other words, the precision of these sampling devices falls, or can be made to fall, within the desired limits for the analysis. However, if the absolute amount of sample taken needs to be known, calibration is required and the possibility of a variation of the volume taken with time must be recognized. Mechanical samplers... 

The European Pharmacopoeia and HP standard viscosimetric method is described in Chapter IS. In the proposed method, both hyaluronidase and hyaluronan are available as well-defined stable standard preparations, eliminating variations in test results due to the absence of a well-defined substrate. With slight modifications the method can be used for the determination of hyaluronidase in serum [137]. 

Additionally, unlike the European specification CEN EN 13108-1 (2008), the compaction of the specimens under the Superpave design methodology is restricted to gyratory compaction only. This is a positive step since it simulates better the compaction carried out on site and eliminates variations on the mechanical properties of asphalt mixtures attributed to type of compaction. 

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