Semiquantitative data

Deviation includes, in fact, the summation of steric and electronic effects, and basicity is somewhat a useful predictor for properties of complex dyes (solvent sensitivity, isomeric forms of trinuclear dyes) and gives also semiquantitative data for color structure relation (atomic)... 

The most widely studied physical property of carbanions is their basicity, which of course is a direct measure of the acidity of the parent carbon acid. Carbon acidity measurements date back to the early part of the twentieth century and a myriad of techniques have been employed for the measurements. Although early measurements were only able to provide semiquantitative data, more recent ones have resulted in accurate acidity measurements across a vast range of effective acid dissociation constants, Ka values. This section will begin with a brief description of definitions and methodologies followed by representative data as well as applications of those data. 

Kinetic analysis of the palladium catalyzed acylation reaction of 1 (R = i-Pr) and 23 indicates that the rate does not depend on the bulk of the trialkylsilyl substituent. Since the rate limiting step of this reaction is the interaction of a coordinatively unsaturated acylpalladium chloride with the cyclopropane (Cf. Eq. 59), the observed independence can reasonably be taken as an evidence that the Si—O bond remains intact in the transition state [56], Semiquantitative data on the cleavage of I (R = i-Pr) and 23 with ZnCl2 in ether, Eq. (13), led to the same conclusion [27]. 

Based on the data in Table 1, on additional semiquantitative data and upon qualitative observations2,9,11 the following order of relative stabilities could be established for borane complexes ... 

Lactic Acid. Qualitative and even semiquantitative data are obtained by paper chromatography. Quantitative procedures where lactic acid is oxidized to acetaldehyde and the acetaldehyde determined colorimetri-cally are available (4,13, 22, 90). 

Consideration of Surface Tool Concerns. Reasonably fast data acquisition, small probing beam size (allowing both faster sputter profiling and spatial resolution) and semiquantitative data analysis, give AES a primary role in each of these two experiments. 

Redistributions occurring at moderate rates may be studied by any of the conventional means. However, NMR has become a very convenient method since the reactions may be performed directly in sealed NMR tubes which are inserted into the thermostated probe of the NMR spectrometer. Although a great number of qualitative statements or semiquantitative data regarding rates of redistribution reactions are found in the literature, only a few systems have been studied quantitatively (298). 

In answering these questions, we must keep in mind that field screening methods produce mostly semiquantitative data that are not acceptable for confirmation sampling or site closure and that the screening method detection limits may not be sufficiently low for comparisons to the action levels. 

All quantitative calculations are carried out by computer programs (2,6,16). Calibration data are at present available for 95 heteroaromatic compound types, including one-to-seven or -eight ring thiophenes, furans, mono- and dihydroxyaromatics, pyrroles, pyridines, and nitrogen/oxygen compounds. Semiquantitative data are available on an essentially unlimited number of additional heteroaromatics. 

Rock properties should be examined at as many outcrops as possible, looking for friability, cementing, degree and nature of fractures and dissolution conduits, and animal burrowing (Figs. 2.3, 2.4, 2.8, and 3.2). However, one should bear in mind that rocks at exposures are altered by weathering and joint formation due to stress release and thus may poorly represent the rocks at depth. Similar observations may be conducted on drill cores, but these are expensive and their record is limited in size. Laboratory tests on cores provide semiquantitative data on the nature of rock pores and fissures and conductivities. 

Quantitative continuous data may be evaluated by standard statistical methods. It is inappropriate to use parametric statistical methods on semiquantitative data (i.e., renal injury light miscroscopic assessment scores), although appropriate non-parametric methods (e.g., Duncan s rank-sum procedure) may be used. 

At least semiquantitative data on the isomer distribution for the halogenation of a given unsaturated heterocycle have been reported, although no quantitative comparisons of the relative reactivities of different heterocycles are available. As a prelude to examining possible theoretical correlations between the observed site of halogenation and a heterocycle s electronic structure, it is useful to discern... 

The differing behavior of lithium halides in PDC and in HMPA is also in agreement with semiquantitative data for the relative EPD strengths of halide ions and EPD solvents (Table VII, Section III). The solvent HMPA is a stronger EPD than both Cl and Br , and hence these ligands are easily replaced by HMPA at the lithium ion on the other hand, PDC is a weaker EPD than Cl and Br , and hence these ligands are only partly replaced despite the large excess of solvent molecules present. 

The inability of the technique to routinely provide anything better than semiquantitative data is more than offset by its wide range of applicability and unusual properties. The combination of high sensitivities - to one part per billion - coupled with the ability to detect any element on the periodic table make SSMS a tool with tremendous usefulness to the microelectronics industry. 

The available data and information to be used in the reconstruction should be ranked from most to least robust. This step is one of the most important in the process, because once a full understanding of the available information is achieved, a strategy can be developed to generate the most appropriate reconstructed values. For a majority of scenarios, quantitative data will be most important and relevant to the assessment, followed by semiquantitative data or estimates, and finally, qualitative data, information, or estimates. 

Direct-injection ESI-MS/MS provides the structural characterization of anthocyanins in the extract and semiquantitative data too... 

Separation of the reaction mixture after oxidation of CLXVIIIa was very difficult Semiquantitative data about the yields of individual transformation products of thiobisphenols CLXVIIIa may give an idea about the ratios of individual reactions which proceed simultaneously in one reaction mixture at ambient tempera-... 

For all equilibrium and rate constants indicated in Scheme 7-4 quantitative experimental results or semiquantitative data from comparisons with related compounds were obtained. The postulated upper limit of the N/O-protonation... 

Qualitative information, such as that shown in Figures I2-16, can be converted to semiquantitative data by careful measurement of peak heights, lb obtain a rough estimate of concentration, the following relationship is used ... 

Discriminant analysis (Figure 31) [41,487, 577 — 581] separates objects with different properties, e.g. active and inactive compounds, by deriving a linear combination of some other features e.g. of different physicochemical properties), which leads to the best separation of the individual classes. Discriminant analysis is also appropriate for semiquantitative data and for data sets, where activities are only characterized in qualitative terms. As in pattern recognition, training sets are used to derive a model and its stability and predictive ability is checked with the help of different test sets. 

Recently, matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) has been exploited to determine the complete profile of peptide messengers contained in a small sample of nervous tissues and even single neurons. This method is fast, sensitive, and provides highly specific and semiquantitative data of the peptides contained in complex mixtures of biological molecules. Other mass spectrometric methods, such as fast atom bombardment and electrospray mass spectrometry, are less sensitive and are also less suitable for the analysis of crude biological samples. 

Azaarenes have been detected in marine and freshwater sediments and street dust. Blumer et al. (8) found an azaarene fraction weighing 0.14 mg/kg of sediment in Buzzards Bay, Massachusetts, and 0.22 mg/kg sediment in a marsh at Wild Harbor River, North Falmouth, Massachusetts. The weight of the azaarene fraction is one to two orders of magnitude less than that of the PAH fraction. The mass spectral method used did not allow identification of individual isomers, but did provide separation of and semiquantitative data regarding homologous series (Table V). 

Spectrochemical methods are useful for what has become known as semiquantitative analysis. Frequently it is not necessary to have high-precision results and often it is only necessary to determine if an element has a concentration above or below some specified concentration. Several different techniques are available to determine the concentration level of an element in a sample and also to obtain semiquantitative data. In spectrochemical analysis semiquantitative results usually imply an accuracy of... 

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