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Qualitative data

H. Maarse and C. A. Visscher, eds. Volatile Compounds in Food, Qualitative Data, 5th ed., Zeist, the Netherlands, 1983. [Pg.7]

A number of attempts have been made to quairtify this model by means of fundamental quantum-mechanical calculations on the free electron transport in metals and alloys, but at dre present time, the qualitative data presented in Table 5.1 will suffice to indicate the U eirds. [Pg.154]

The following techniques can be used to collect data about human performance in CPI tasks and provide input to task analysis methods described in Section 4.3. These data can include process information critical for the task, control strategies used by the workers, diagnostic plans etc. A distinction can be made among data collection methods that provide qualitative data (such as interviews, observations, and sources of documentation) and methods that can be used to measure aspects of performance (such as activity analysis, simulations, and information withholding). The latter methods can provide more precise data which can be quantified. [Pg.154]

Up to now only qualitative data have been available on potential-dependent MC measurements of electrochemical interfaces. When metals or other highly conducting materials are used, or when liquids are in play, special care has to be taken to allow access of microwave power to the active electrode/electrolyte interface. [Pg.457]

The question arises as to how useful atomistic models may be in predicting the phase behaviour of real liquid crystal molecules. There is some evidence that atomistic models may be quite promising in this respect. For instance, in constant pressure simulations of CCH5 [25, 26] stable nematic and isotropic phases are seen at the right temperatures, even though the simulations of up to 700 ps are too short to observe spontaneous formation of the nematic phase from the isotropic liquid. However, at the present time one must conclude that atomistic models can only be expected to provide qualitative data about individual systems rather than quantitative predictions of phase transition temperatures. Such predictions must await simulations on larger systems, where the system size dependency has been eliminated, and where constant... [Pg.57]

No comparative kinetic study has been made on the same alkyl carbonyl system for two members of a given transition metal triad. Qualitative data show that the middle member is more reactive than the heaviest one e.g., CpMo(CO)jR > CpW(CO)jR (Section VI,B), Rh(III) > Ir(III) (Section VI,E), and Pd(II) > Pt(II) (Section VI,F). However, the extreme unreactivity of CpW(CO)jR and a considerable difference in lability between most alkyls of Rh(III) and Ir(III), as well as those of Pd(II) and Pt(II), have prevented detailed investigations. Surprisingly, no kinetic studies have been conducted on insertion reactions of RRe(CO)5, which would seem readily amenable to such investigations. [Pg.103]

This approach allowed us also to determine the difference in the surface potentials between mutually saturated water and an organic solvent namely, nitrobenzene, nitroethane and 1,2-dichloroethane, and isobutyl methyl ketone (IBMK). The qualitative data show a very strong influence of the added organic solvent on the surface potential of water, while the presence of water in the nonaqueous phase has practically no... [Pg.46]

The results found in this work indicate that SEC/LALLS can be used to obtain qualitative data about polymer branching. [Pg.124]

Spectrophotometric and spectrofluorimetric methods provide a wealth of information concerning structural determinations (identification, purity and precise measurement of concentration) and chemical changes in alkaloids. These techniques yield both quantitative and qualitative data on the effect of solvents, pH and other physiological conditions [141-143]. X-ray crystallography, H and NMR spectroscopy, infrared spectroscopy (IR) and circular dichroic spectroscopy were also used to study the physical properties... [Pg.173]

The qualitative data on the absorption, distribution, metabolism, and excretion of hydrogen sulfide in humans and animals are well known. Quantitative data are generally lacking. Additional animal data through collection by quantitative measurements are collected are needed, as well as data on changes in these parameters with exposure. [Pg.129]

Although relaxation measurements have been widely used in nuclear magnetic resonance studies of solid catalysts and adsorbed molecules, they have not found such favor in similar ESR work. Relaxation phenomena, however, do play a very important role in any magnetic resonance experiment, whether or not this aspect of the problem is studied. In fact, the temperature at which most ESR experiments are conducted is dictated by the relaxation process. Furthermore, even qualitative data on relaxation times can be used as supporting evidence in the identification of a paramagnetic species. [Pg.279]

The organic analogues of the reactions to be discussed here are the borane reductions of aldehydes and ketones and the addition of metal alkyls across ketonic carbonyls, equation 15. In contrast to the ease of these organic reactions, qualitative data which has accumulated in our laboratory over the last decade demonstrates that the carbonyl group in organometallies is fairly resistant to addition across CO. For example, many stable adducts of organometallie carbonyls with aluminum alkyls are known, eq. lc, but under similar conditions a ketone will quickly react by addition of the aluminum alkyl across the CO bond. A similar reactivity pattern is seen with boron halides. [Pg.17]

The human experience is defined by only qualitative data. These data, however, affirm the extreme toxicity of arsine and the characteristic latency... [Pg.113]

Information regarding human exposures to dimethylhydrazine are limited to a few case reports. Although case reports provide qualitative data regarding signs and symptoms of exposure, no exposure concentration data or precise exposure duration data were reported. Signs and symptoms of exposure included respiratory effects, nausea, vomiting, neurologic effects, pulmonary edema, and increased serum enzyme levels (reviewed in Trochimowicz et al. 1994). [Pg.179]

Antibody-based detection methods include immuno-cytochemistry, which gives qualitative data but has very good spatial resolution. Radioimmunoassays provide a quantitative measure of release or content. One of the major limitations of all antibody-based methods is the potential for cross-reactivity among the many peptides. For example, some of the most sensitive gastrin antisera also detect CCK, since the peptides share a common COOH-terminal tetrapeptide sequence. Methods for detection of the mRNAs encoding neuropeptides include Northern blots, which provide quantitative data and information on splice variants, but lack fine anatomical resolution. The more commonly used polymerase chain reaction, which can be quantitative but often is used in a more qualitative manner, provides great sensitivity. Alternatively, in situ hybridization preserves anatomical relationships and can be used to obtain both qualitative and quantitative data. [Pg.328]

When the qualitative data of the various authors are compared, it seems that the cyclization of A-(3-alkoxyphenyl)aminomethylenemalonates is not too sensitive to the cyclization conditions, and mainly 7-alkoxyquino-line-3-carboxylates are obtained. [Pg.176]

Feher [15] Crivori et al. [12] Keseru and Molnar [26] Data set assembled by Luco New qualitative data set Young s data set + Abraham s data set + new compounds... [Pg.546]

The simplest form of qualitative data is binary data in which there are only two possible values, for example, death/survival or success/failure each of which needs to be defined within a specified time interval has pain relief been achieved within two hours of treatment, success - or not, failure. This form of data is extremely common in medical research and yet it ignores the possibility of gradation, success may not be total but only partial and yet not be total failure. These considerations lead naturally to the concept of ordered categorical or ordinal data. [Pg.277]

The Introduction section of a journal article Identlhes the research area, explains the Importance of the research, provides background Information, cites and summarizes key literature in the held, points out what still needs to be studied, and Introduces the reader to the work presented In the article. The Methods section—formally known as Materials and Methods or Experimental (Section)— describes how the study was conducted. The Results section summarizes quantitative (and possibly qualitative) data collected during the study. In the Discussion section, authors interpret their data and suggest the larger implications and/or applications of their results. Each of these major sections can be further divided into moves, as we will see in subsequent chapters. [Pg.45]

This literature does not paint an optimistic picture. Whilst it is true that there are caveats, that there will be exceptions, the broad canvas clearly indicates a strong likelihood of problems and poor outcomes. The research that I will describe in the rest of the book does not offer much of a detour. As it is based upon qualitative data, however, it provides an opportunity to flesh out something of the texture of the family experience. Before doing this it is necessary to describe the research projects that informed this book. [Pg.20]

Thiolysis also proved useful for the analysis of derived tannins. Methylmethine-linked tannin-like compounds resulting from acetaldehyde-mediated condensation of flavanols (see Section 5.5.S.2) yielded several adducts when submitted to acid-catalyzed cleavage in the presence of ethanethiol, providing information on the position of linkages in the original ethyl-linked compounds. " Thiolysis of red wine extracts released benzylthioether derivatives of several anthocyanin-flavanol adducts, indicating that such structures were initially linked to proanthocyanidins. However, some of the flavonoid derivatives present in wine (e.g., flavanol-anthocyanins ) are resistant to thiolysis, while others (e.g., flavanol-ethyl anthocyanins) were only partly cleaved. Thiolysis, thus, appears as a rather simple, sensitive, and powerful tool for quantification and characterization of proanthocyanidins, but provides mostly qualitative data for their reaction products. [Pg.271]

Maarse, H. Visscher, C.A. Volatile Compounds in Food. Qualitative Data TNO-CIVO Food Analysis Institute Zeist, The Netherlands, 1987. [Pg.199]

Over the last 10 years, all these severe limitations of the traditional molecular mechanics approach have been tackled. The appropriate use of molecular mechanics, molecular dynamics, quantum mechanics and computer graphics has given in a number of cases useful qualitative data on solvation and binding, with good agreement between theory and experiment (Kollman and Merz, 1990). [Pg.58]

In vitro systems containing human xenobiotic-metabolizing enzymes can provide qualitative data, such as the human metabolites which may be produced in vivo and which enzymes are capable of producing these metabolites. When comparing quantitative aspects of metabolism among different cytochrome P450 forms in a cDNA expression system, the data can be interpreted in two contexts ... [Pg.195]


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