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Fine structure without

The isotropic form has little graphitic characteristic and essentially no optical activity. It is composed of very fine grains without observable orientation and for this reason, it is known as isotropic carbon rather than isotropic graphite. It is often obtained in fluidized-bed deposition, possibly due to continuous surface regeneration by the mechanical rubbing action of the bed. An isotropic structure, observed by transmission electron microscopy, is shown in Fig. 7.4.111]... [Pg.191]

The second and third energy terms in equation (1) could be interchanged without any effect (i.e. it is impossible to say which electron fills the initial core hole and which is ejected as an Auger electron they are indistinguishable. The existence of different electronic states within the final doubly ionized atom may furthermore lead to fine structure in high-resolution spectra. [Pg.172]

Fourier transformation without data manipulation leads to the multiplet at the bottom (a), which shows more fine structure when a negative LB value is used (b). The spectrum in the middle (c) results from use of the SSB function, and now all eight lines are clearly visible as the linewidth is much smaller. The price we pay is that the lineshape is completely changed, the positive central... [Pg.8]

The fine structure of the membrane also allows surface filtration to occur. Suspended solid particles are retained on the surface of the membrane and are not allowed to penetrate into or through the supporting felt cloth. In contrast, conventional media depend upon depth filtration in which particles are retained within the medium itself. The results are immediate filtrate clarity without the need to build-up a filter cake, and reduced accumulation of solids within the medium that leads to increasing pressure drop. [Pg.295]

C-NMR refers to recording another NMR-spectrum but of the C-13 atoms rather than the hydrogen atoms. In actual practice, however, - these spectra are recorded in such a manner that each chemically distinct carbon gives rise to single peak, without any coupling or fine structure . [Pg.348]

They prove that the platinum oxidation state can be finely varied without causing important structural changes, but for a progressive elongation of the Pt-Pt distance with the decrease of the overall charge. [Pg.521]

Note that the number of diffraction peaks decreases with time as the droplet diameter decreases, and the number density of peaks is very nearly proportional to the droplet size. The intensity of the scattered light also decreases with size. The resolution of the photodiode array is not adequate to resolve the fine structure that is seen in Fig. 21, but comparison of the phase functions shown in Fig. 22 with Mie theory indicates that the size can be determined to within 1% without taking into account the fine structure. In this case, however, the results are not very sensitive to refractive index. Some information is lost as the price of rapid data acquisition. [Pg.45]

A comparison of the absorption edge of catalyst A with and without MgO shows considerable differences (Figure 12). Though the oxidation state of V is essentially the same, the edge fine structure induced by MgO indicates that the local environment about V had been altered significantly. As with the cyclic microunit studies, the... [Pg.224]

The toxic effects of ozone in plant systems have been studied for some time, yet the actual mechanisms of injury are not fully understood. In addition to visible necrosis which appears largely on upper leaf surfaces, many other physiological and biochemical effects have been recorded ( ). One of the first easily measurable effects is a stimulation of respiration. Frequently, however, respiration may not increase without concomitant visible injury. Furthermore, photosynthesis in green leaves as measured by CO2 assimilation, may decrease. It is well known that ozone exposure is accompanied by a dramatic increase in free pool amino acids ( ). Ordin and his co-workers ( ) have clearly shown the effect of ozone on cell wall biosynthesis. In addition, ozone is known to oxidize certain lipid components of the cell ( ), to affect ribosomal RNA (16) and to alter the fine structure of chloroplasts (7 ). [Pg.8]

Because of the favorable cross-peak multiplet fine-structure, the HSQC experiment offers superior spectral resolution over the HMQC (heteronuclear multiple quantum coherence) experiment [13, 14], On the other hand, the HMQC experiment works with fewer pulses and is thus less prone to pulse imperfections. The real advantage of the HSQC experiment is for measurements of samples at natural isotopic abundance and without the use of pulsed field gradients, since the HSQC experiment lends itself to purging with a spin-lock pulse. Spin-lock purging in the HMQC experiment... [Pg.154]

As was noted in [28] this contribution may be obtained without any calculations at all. It is sufficient to realize that with logarithmic accuracy the characteristic momenta in the leading recoil correction in (10.3) are of order M and, in order to account for the leading logarithmic contribution generated by the polarization insertions, it is sufficient to substitute in (10.5) the running value of a at the muon mass instead of the fine structure a. This algebraic operation immediately reproduces the result above. [Pg.203]

The key quantities in the traditional Bom-Oppenheimer theory of molecules are the coordinate-dependent electronic energies. They supply the potentials for nuclear motion from which the level fine structure can be predicted. These curves or surfaces need not necessarily be obtained from ab initio theory. The inverse approach is followed in most spectroscopic work in that the potential-energy surfaces or sections thereof are extracted from experiment. Indeed, the structural information contained in the electronic energies provides the most commonly used interface for the comparison between ab initio theory and experiment. Without this key feature of the theory, molecular physics could never have progressed as it has in the past decades. [Pg.706]

Scattering has been measured for Ne + Ne, Ar + Ar, and Dr + Kr by different groups at thermal energies, but no data and potentials have been published so far, as the analysis is quite involved. First, it is impossible to quench one of the two metastable states without an expensive laser, so that an investigator is generally forced to work with mixtures and second, six potentials contribute coherently for the dominant 3P2 species. The cross sections for fine-structure changing collisions are small78 80 and hence can... [Pg.536]

Disulfide bonds may exhibit a broad band of ellipticity in the range of 240 to 350 nm. This can be confused with the band associated with the La transition of tryptophan but, in cases where a disulfide makes a significant contribution to the CD, it can be recognized by its ellipticity above 320 nm. It can augment or diminish the apparent intensity of tryptophan and tyrosine contributions without being recognized as such and without fine structure necessarily being lost. [Pg.236]


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See also in sourсe #XX -- [ Pg.46 ]




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Fine structure

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