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Diagnostic characters

Diagnostic characters of new species of phanerogamous plants collected in Japan... [Pg.313]

Anderson, N.L., Anderson, N.G. (2002). The human plasma proteome history, character, and diagnostic prospects. Mol. Cell. Proteomics 1, 845-867. [Pg.285]

As a result of the small, but apparent single bond character of the triafulvene C3/C4 bond and the good stabilization of the transition state of the rotation established earlier, rotation around this bond should be lower in energy in comparison to simple ethylene derivatives183. In fact, 1H-NMR spectra of several types of asymmetrically substituted triafulvenes 219-224 proved to be temperature-dependent and showed reversible coalescence phenomena at definite temperatures diagnostic for internal rotation processes. These were characterized by the free enthalpy of activation AG at the coalescence point of appropriate substituent signals61. ... [Pg.57]

EPR-IR. The neutral sandwich complexes of Lu and the one-electron oxidized sandwich complexes of Zr have a jr-radical anion that can be observed by EPR spectroscopy. The EPR spectra for compounds 21, 23, 25, 27 and Collman s mixed porphyrin-pz system (30) give a signal for an S = j system with a g value of 2.0037, which is typical for an organic n radical (35). Further evidence for the Jt-radical character in sandwich compounds of phthalocyanines, porphyrins, and porphyrazines may be obtained from infrared (IR) spectroscopy by the presence of diagnostic marker bands (81). These intense bands are found in the IR spectra of Lu(III) compounds (21) (1150 cm-1) (35), 23 (1140 cm-1) (78), and 25 (1261 cm4) (34) and are absent in the Zr(IV) and Ce(IV) compounds 27,29, and 31. [Pg.493]

While CCSD and especially CCSD(T) are known [36] to be less sensitive to nondynamical correlation effects than low-order perturbation theoretical methods, some sensitivity remains, and deterioration of W1 and W2 results is to be expected for systems that exhibit severe nondynamical correlation character. A number of indicators exist for this, such as the T diagnostic of Lee and Taylor [64], the size of the largest amplitudes in the converged CCSD wavefunction, and natural orbital occupations of the frontier orbitals. [Pg.56]

On the other hand, the PAs at the para and ortho positions are manifestly more sensitive to the electron correlation treatment than the PA at the nitrogen. From the point of view of the % diagnostic (a measure for the importance of nondynamical correlation), aniline (7 =0.0113) and N-anilinium (7 =0.0096) are very similar (and basically purely single-reference), while the p- and o-protonated species exhibit very mild multireference character (0.0149 and 0.0157, respectively). Since protonation at these sites thus involves a noticeable change in 7i, the PA is expected to be more sensitive to the correlation method. [Pg.189]

Infrared spectroscopy is the only method that gives direct, diagnostic information about the presence of a diazo group in diazoazoles. The aromatic character common to the diazoazoles and diazocyclopentadiene and the importance of the contributions of the different mesomeric forms to the resonance hybrids in the ground state are reflected in the position of the bands associated with the diazo group in the infrared spectra (Table IV). [Pg.73]

The adsorption microcalorimetry has been also used to measure the heats of adsorption of ammonia and pyridine at 150°C on zeolites with variable offretite-erionite character [241]. The offretite sample (Si/Al = 3.9) exhibited only one population of sites with adsorption heats of NH3 near 155 kJ/mol. The presence of erionite domains in the crystals provoked the appearance of different acid site strengths and densities, as well as the presence of very strong acid sites attributed to the presence of extra-framework Al. In contrast, when the same adsorption experiments were repeated using pyridine, only crystals free from stacking faults, such as H-offretite, adsorbed this probe molecule. The presence of erionite domains in offretite drastically reduced pyridine adsorption. In crystals with erionite character, pyridine uptake could not be measured. Thus, it appears that chemisorption experiments with pyridine could serve as a diagnostic tool to quickly prove the existence of stacking faults in offretite-type crystals [241]. [Pg.245]

This study demonstrates high efficacy and expediency of the TCNQ derivative-based point-contact multistracture as a prospective asset for development of new sensors. The complex character of the sensors response curve and correlation of some response characteristics with different pathological manifestations in human breath, may be further used as a noninvasive diagnostic method alternative to some invasive approaches currently routinely used in clinic. The need for reliable and feasible gas analysis methods functional in presence of atmospheric air, opens opportunities for application of the proposed sensor technique in other spheres of human activity. High sensitivity of the point-contact multistructure enabling analysis of composite gas mixtures, opens up wide possibilities to apply the demonstrated approach for environment and health protection, such as detection of trace amounts... [Pg.73]

The CCSD(T) level is reasonably forgiving even in instances where the single-determinant assumption is questionable. Some discussion of tliis point with examples is provided in the next section. Here, however, we note that one measure of the multireference character that is often reported is die so-called Ti diagnostic of Lee and Taylor (1989), defined as... [Pg.226]

CTTS transitions in coordination compounds result in a radial movement of electron density from the metal to the surrounding solution medium. The energies of these transitions generally are very sensitive to environmental parameters such as solvent polarity, temperature and the presence of salts.104 This sensitivity has been used in a diagnostic sense to identify CTTS bands in the spectra of anionic cyanide complexes105 and 1,2-dithiolene complexes of Ni, Pd and Pt.106 Hydrated cations such as Cr2+(aq) and Fe2+ (aqj exhibit absorption bands that are sometimes referred to as CTTS in character. Since the solvent occupies the first coordination sphere of the metal, however, the distinction between CTTS and CTTL transitions in these systems becomes obscured. [Pg.405]


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See also in sourсe #XX -- [ Pg.146 ]




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