Position of signals

In analytical practice, Q-z-evaluation refers to the position of signals on energy scales or scales that are related to energy, such as frequency-,... 

Figure 4. Hydroxyl PMR signals (solvent, methyl sulfoxide-d6) for A) D-fructose after prior equilibration in water B) D-fructose at equilibrium in methyl sulfoxide-d6 C) leucrose, freshly dissolved crystals D) furanose, freslily dissolved crystals (arrows show the positions of signals that increase in intensity with time) G2-hydroxyl proton-2, F4-hydroxul proton-4 E) lactulose, freshly dissolved crystals. At the upper right are 13C-2 signals at 25.15 MHz for D-fructose in water (see Reference...

The relative position of signals is determined by shielding and deshielding effects. 

The nature of the solvent exerts only a moderate influence on the position of signals in this series. For example, 4-amino-5-hydroxymethyl-2-methyl-l,2,3-triazole gave a 2-Me signal at d 3.91 in perdeuterated dimethyl sulfoxide, at... 

Zero filling beyond a factor of two also can be done, but does not produce further improvement in line width. It is useful, however, in quantitative work (Section 2-6c), because it provides more data points to define line shapes and the positions of signals. 

RBS spectra of the initial rubber (1) and a sample upon which the Mo coating was deposited and also irradiated with 3 keV Mo+ ions (2) are shown in Fig. 1. Vertical marks indicate the position of signals from identified elements entering into rubber composition and into the surface of the coating/rubber construction. 

Nor did the analysis of the values of Ji3c 1h the position of signals in the NMR- C spectra allow one to draw unequivocal conclusions on the character of the complexes resulting from the reaction of benzene derivatives with Hg(OCOCF3)2 The authors consider the data obtained to conform with the formation of a-and jc-complexes undergoing quick interconversions. 

Listed below are the abbreviated notations of the main standards and the values of their chemical shifts (ppm) which were accepted by most workers in determining the position of signals in the PMR spectra of arenium ion salts ... 

Fig. 1. X-band ESR spectra of VO + (—) (a) at 253 K, in chemically cross-linked polyacrylamide gels swollen by water (b) at 278 K, in chemically cross-linked polyacrylamide gels swollen by water/acetone mixture (80 20 v/v). Simulated spectra (—-) based on the rigid limit model in (a) and motionally narrowed model in (b). Stick diagrams show the positions of signals for the parallel and perpendicular components (a) and isotropic component (b). DPPH is used as ag-marker, g = 2.0036.

All FMR spectra of our samples show signals which are typical (75) for B-Co, which has a face-centered-cubic structure (the position of signal does not depend on the examination temperature). For sample 0.90T, the width, shape, and position of the resonance line are very similar to those reported by Bean (75) for spherical Co particles with D = 5 nm we thus infer a similar size for the Co particles in sample 0.90T (Table I). Unfortunately, the limited amount of data available for small spherical Co particles (14,17) limits the quantitative use of the AH values. 

What information is provided by the positions of signals in an nmr spectrum How many signals are expected in each of the following ... 

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