INDEX errors

In an effort to avoid reproducing indexing errors from other systems, hard copy of all articles selected for inclusion into the data base is always obtained before information is entered into the ETIC file. When a complete copy of an article is in hand, the bibliographic data are entered into the computer. The fields that are entered include the author, title, citation, literature type, language or translation notes, secondary source, and selected abstracts. The technical staff then indexes the data using experimental parameters that allow searching in a variety of ways specific to the interests of the users. Only that portion of the paper concerned with teratology or... 

In the case of Langmuir monolayers, film thickness and index of refraction have not been given much attention. While several groups have measured A versus a, [143-145], calculations by Knoll and co-workers [146] call into question the ability of ellipsometry to unambiguously determine thickness and refractive index of a Langmuir monolayer. A small error in the chosen index of refraction produces a large error in thickness. A new microscopic imaging technique described in section IV-3E uses ellipsometric contrast but does not require absolute determination of thickness and refractive index. Ellipsometry is routinely used to successfully characterize thin films on solid supports as described in Sections X-7, XI-2, and XV-7. 

Pure, low temperature organic Hquid viscosities can be estimated by a group contribution method (7) and a method combining aspects of group contribution and coimectivity indexes theories (222). Caution is recommended in the use of these methods because the calculated absolute errors are as high as 100% for individual species in a 150-compound, 10-family test set (223). A new method based on a second-order fit of Benson-type groups with numerous steric correctors is suggested as an alternative. Lower errors are claimed for the same test set. 

The performance index for MPC applications is usually a linear or quadratic function of the predic ted errors and calculated future control moves. For example, the following quadratic performance index has been widely used ... 

Equation (9-54) may be solved for i either graphically or by an iterative trial-and-error procedure. The value of i given by Eq. (9-54) is known as the discounted-cash-flow rate of return (DCFRR). It is also known as the profitability index, true rate of return, investor s rate of return, and interest rate of return. 

For single rings (i.e. mononuclear systems) up to ten atoms in size, there is no question but that Hantzsch-Widman names are overwhelmingly the most widely used, and specialists can be presumed to recognize them readily. However, when one of the trivial names of Table 1 can be used, it prevails almost exclusively. Thiophene will be immediately understood by specialists and most nonspecialists, whereas thiole will distract the reader s attention from the chemistry while he considers the writer s intention is the Hantzsch-Widman system indeed being used, or is it a typographical error Chemical Abstracts also uses these trivial names in its indexes. 

Transient torques Gears with indexing or positioning errors. 

If the performance index or cost function J takes the form of a summed squared error function, then... 

The program identifies those values of (k) and (ni) that provide the minimum error between the calculated values and the experiential values for the refractive index of the mixtures. The results obtained are shown in Figure (27). Excellent agreement... 

A slit die is designed on the assumption that the material is Newtonian, using apparent viscous properties derived from capillary rheometer measurements, at a particular wall shear stress, to calculate the volumetric flow rate through the slit for the same wall shear stress. Using the correction factors already derived, obtain an expression for the error involved in this procedure due to the melt being non-Newtonian. Also obtain an expression for the error in pressure drop calculated on the same basis. What is the magnitude of the error in each case for a typical power law index n = 0.377... 

List of the factors considered for each error and the relative weight of each factor assigned, and Final index values and the calculated HEP for each error considered. 

In the SLIM procedure, tasks are numerically rated on the PIFs which influence the probability of error, and these ratings are combined for each task to give an index called the success likelihood index (SLI). This index is then converted to a probability by means of a general relationship between the SLI... 

A more difficult criterion to meet with flow markers is that the polymer samples not contain interferents that coelute with or very near the flow marker and either affect its retention time or the ability of the analyst to reproducibly identify the retention time of the peak. Water is a ubiquitous problem in nonaqueous GPC and, when using a refractive index detector, it can cause a variable magnitude, negative area peak that may coelute with certain choices of totally permeated flow markers. This variable area negative peak may alter the apparent position of the flow marker when the flow rate has actually been invariant, thereby causing the user to falsely adjust data to compensate for the flow error. Similar problems can occur with the elution of positive peaks that are not exactly identical in elution to the totally permeated flow marker. Species that often contribute to these problems are residual monomer, reactants, surfactants, by-products, or buffers from the synthesis of the polymer. 

A common error is to confuse the GPC distribution with the weight distribution. The response of a refractive index detector is proportional to the mass of polymer. The GPC elution volume (V) typically scales according to the logarithm of the degree of polymerization (or the logarithm of the molecular... 

Samples of the 1,4-dihydrobenzoic acid, after both the first and the second distillations, are transparent in the ultraviolet region between 220 mu and 300 m/i, indicating the absence of benzoic acid or conjugated dihydrobenzoic acids. The refractive index cited in Reference 3 is in error. 

All of the observed reflections could be indexed on the basis of a cubic unit cell with Oo = 11.82 A the estimated probable error is 0.01 A. The only systematic absences were hhl with l odd this is characteristic of the space group 0 -PmP>n, which also was reported by von Stackelberg from his single-crystal work on sulfur dioxide hydrate. For 46 H20 and 6 Cl2 in the unit cell the calculated density is 1.26 densities reported by various observers range from 1.23 to 1.29. 

It is seen that errors in the smaller component can be as great as 12.5% (1.25% absolute) when the response index is 0.94. Yet on examining the curve for a response index of 0.94 in figure 2 the non-linearity is scarcely apparent. When the response index is 1.05 the error is 9.5% (0.95% absolute) and again the poor linearity is not obvious in figure 2. As already stated, to obtain accurate results without employing a correction factor, the response index should lie between 0.98 and 1.02. Most LC detectors can be designed to meet this linearity criteria. 

The general equation for the gel effect index, equation (la) which incorporates chain transfer, was used in those cases where there was not a good agreement between model predictions and experimental data. The same values of and (derived from the values of and C2 found at high rates) were used in the integration of equation (1) and the value of the constant of chain transfer to monomer, C, was taken as an adjustable parameter and used to minimize tfie error of fitting the time-conversion data by the model. 

The entries of this index were derived directly by computer program from the lists of references. The accuracy of the references was the sole responsibility of the authors. No editorial check, except for format and journal-title abbreviation, was applied. Consequently, errors occurring in authors names in the references will recur in this index. 

Particular attention has been devoted to the compilation of the cumulative index. Every reference work is only as good as its indexing system. For this reason a presentation has been chosen which allows one to recognize immediately in which volume the key word appears. The same also applies to named reagents which can be traced back to the original publication in almost all cases in order to be able to correct any errors that have crept in. This type of presentation will be continued in future volumes. 

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