Spreading shift factor

Dynamic Wettability In electrophotography, the toner spreading process has been characterized by the following shift factor (3) ... 

Open-ended, Computer) Using the WLF constants of Table 4-1, generate log shift factors at 5 temperatures above Tg, e.g., Tg + 2, 7, 12, 17, and 22 °C. To these add a small amount of error, using random deviates with 0.03-decade standard deviation (many spread sheets will generate these for you). Using the two linearized forms of the WLF equation ... 

Each corporate bond will only be exposed to one of these factors, with an exposure that will typically increase with the bond s maturity. A rule of thumb is that it will be comparable to the bond s exposure to the shift factor. The spread risk of almost all AAA, AA, and A rated bonds will be less than their interest rate risk, and it is only for BBB rated bonds and in some very specific market sectors such as Energy and Telecoms that spread risk starts exceeding benchmark risk. Spread risk is by far the dominant source of systematic risk for high-yield instruments. 

It is evident from the above table that a considerable spread of chemical shift values is observed in tellurium-transition metal complexes, but the factors that determine the chemical shift are still poorly understood and data are not available for all known structural types. The most extensive compilations of data have been provided by Rauchfuss (187) and Herrmann (191), with the point being made in the former reference that chemical shifts are extremely sensitive to changes in cluster geometry. In principle, 12sTe NMR spectroscopy is a valuable method for studying tellurium-transition metal clusters in solution, but it is clear that more data are required before unambiguous structural assignments can be inferred. 

Note that in Figure 12, both T and S are functions of frequency. The overlap in data for different frequencies indicates the shift in the peak and spread of damping factor as a function of frequency. Thus data for tan (6) correlates well with the model for G. ... 

A major consequence of the introduction of pulse (FT) NMR spectroscopy has been ready access to C data - limited prior to 1970 by factors which render this magnetic nucleus relatively insensitive to continuous wave methods of recording NMR spectra (1 % natural abundance, and low value of the nuclear magnetic moment compared with that of a proton). C-NMR spectra are generally much simpler than corresponding H spectra. When run under conditions where all couplings to protons are removed (by simultaneous wide-band irradiation of proton resonances), a C-NMR spectrum consists of a series of sharp lines, each of which corresponds to the resonance of a nucleus (or nuclei) of specific magnetic environment. Further, since the chemical shift spread of C nuclei (0-200 ppm) is about 20-times that of protons. 

The attainable resolution is limited by spectroscopic and hardware factors. Spectroscopic factors are the linewidth and the spread of the chemical shift of an NMR signal, diffusion processes and susceptibility gradients, both within the object and at its boundaries. Hardware factors may be the magnetic field inhomogeneity or instability, nonlinearity of the magnetic gradient field and the achievable signal-to-noise ratio. 

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