Spectra widths

Infrared spectra of the unfilled and filled copolymers were measured using a Perkin-Elmer model 1700 FTIR spectrometer. The 13C CP/MAS NMR measurements were conducted on a Bruker 300 instrument operating at 75.51 MHz. The samples were rotated with a spectra width of 40.0 Hz, the CP time was 5 ms. l3C lI distortionless enhancement by polarization transfer (DEPT) technique was applied for analysis of monomers. The process was performed at 75.51 MHz, rotated with a spectral width of 0.75 Hz and a CP time of 15 ms. Atomic force microscopy measurements were carried out using a Nanoscope Ilia controlled Dimension 3000 AFM (Digital Instrument, Santa Barbara, CA). 

Determination of PHA polymer composition by nuclear magnetic resonance (NMR). Twenty mg of each polymer was dissolved in 1 ml of CDCI3 and subjected to both H and C NMR analysis. H NMR spectra were recorded using a JEOL a-400 spectrometer with a 5.0 ps pulse width (45 pulse angle), 3-s pulse repetition, 7500-Hz spectra width, and 16K data points. For C NMR analysis, ta were collected using a JEOL ECP-500 spectrometer with a 7.0-ps pulse width (45° pulse angle), 5-s pulse repetition, 25000-Hz spectra width, and 64K data points. Tetramethylsilane (Me4Si) was used as an internal chemical shift standard. 

Bowker concluded that it is necessary to invoke an activated nitrogen dissociation step in order to reproduce the experimental findings on industrial catalysts as well as the measured desorption spectra widths. It is not clear from the article, whether the surface coverages given in the table are average or typical for the exit of the reactor. Bowker discussed the differences between the different crystal planes of iron, both promoted and nonpromoted, but he still assumed in his model the surface to be homogeneous. 

Fig. 1. P-NMR spectrum of 50 mA/HjP 04 (40 atom % 0,27 atom % K)) in DjO, pD 1.8 at 81.0 MHz. Spectral parameters acquisition time 4.1 s, delay 1.0 s, spectra width 2 kHz, 70° pulse, line broadening 2.0 Hz, 1600 scans. The inset shows the expanded spectrum of the sharp peak, processed with Gaussian multiplication (LB = —2, GB= 0.2). Chemical shift 0.09 ppm downfield from 1 Af H3PO4.

One may hope that the results presented in Eq. (3.23) and Eq. (3.24) remain valid beyond the framework of impact theory. As is seen from Chapter 1, linear in density Eq. (3.21) and Eq. (1.124) become invalid in highly dense media. However, it is unlikely that their relative efficiency will be considerably changed. Thus the direct proportion (3.24) may be retained even in the case where 1/xj increases nonlinearly with increase in density (see Fig. 1.23). Since it is easier to measure xj in the liquid than xe, it is of some importance to express the isotropic spectrum width as a function of xj. 

Fig. 3.19 ESR spectra of the 16-PC probe in total lipid (TL) liposomes. (A) control (B) TL-nifedipine (2 1 molar ratio) (C) TL-verapamil (2 1 molar ratio). Spectrum width 6 mT. Temperature 37°C. Arrows in spectrum (A) indicate 4max determination, arrows in spectrum (C) indicate 4min. (Reprinted from Fig. 2 of ref. 68 with permission from Elsevier Science.)...

Akasaki and Amano [17] reported high-efficiency UV GaN/AlGaN DH LEDs with an external quantum efficiency of 1.5%. The spectrum width of the emission observed by them was as broad as 30 nm at a peak wavelength of 370 nm. 

With respect to an external standard of aqueous LiCIO the larger peak is 11.95 ppm downfield, the smaller 1.6 ppm upfield, with the displayed spectrum width in the figure equal to 4000 Hz. The downfield peak arises from Li-naphthalenide, with the shift arising from the Fermi contact term (at room temperature for lithium, a shift downfield of 10 ppm corresponds to a hyper fine constant of + 0.005 mT = 4- 0.05 G). At short reaction times, the downfield peak is even broader than shown here, possessing a full width at half maximum of 880 Hz. 

Figure 3b. The Li-7 NMR (34.8 MHz) of n-butyllithium in n-hexane. With the spectrum width equal to 4000 Hz, the single sharp peak comes at 1.6 ppm downfield from LiCIOt (aq). In the context of this chapter, a positive value of chemical shift...

The Pt NMR parameters of the two published Pts clusters are reported in Table 9 [21] and an example of the complex spectra obtained for such species is presented in Figure 5. In the cluster containing iron, one of the platinum resonances has not been observed because the spectrum width was not large enough to observe the whole spectrum. The relative sign of /( PtA, Pto) can be obtained since the platinum spectrum is of second order. 

There are two important time scales. The one we shall call the NMR time scale it has a characteristic time that is the reciprocal of the spectrum width in hertz, typically about 10"3 s. The other is the time scale of molecular tumbling, with a characteristic time of the order of 10"11 s. The rate of molecular motions relative to these time scales determines major features of the symmetry and structure of the observed spectra. 

Oil industry has a long history of application of NMR spectroscopy for characterization of crude oils, products and oil fractions. The methodology has been mainly ID proton- or carbon-detected experiments. Quantitative NMR and NMR experiments have been used in estimation of aromatic, olefin, naphtene and paraffin proportions in the samples. ° A more detailed characterization has been obtained using various ID carbon-detected experiments, like GASPE, CSE, QUAT and DEPT to obtain quantitative CH sub-spectra. " The goal of characterization of the oil fractions and quantification of certain structural features has been to find correlation between these features and the product properties (e.g. viscosity index, pour point). Due to environmental concerns oil companies are nowadays more interested in development of lubricant base oils that have low aromatic and olefin contents. Hydrogenation of unsaturated components also improves the stability of the base oils, which is an important property for the end-product. Quantitative analysis of a saturated oil fraction with NMR is a major challenge. When the oil fraction contains only aliphatic compounds, the spectrum width that contains the resonances narrows to ca. 1 ppm in the NMR spectrum and ca. 50 ppm in NMR spectrum. This causes excessive... 

Equation 36 indicates that the sensor output noise is linearly dependent on the noise of measured signal and inverse linearly dependent on the depth of the SPR dip. If the number of measured intensities M is proportional to the investigated spectrum width, the sensor output noise depends on the square root of the width. 

Absorption spectrum generally has a wide spectrum width. By the irradiation of narrow-width laser light, molecules with absorption frequency resonant to the laser light are selectively excited, and a hole is formed in the absorption spectrum. This is called hole burning. 

The spectrum width at the half-maximum was proposed as a quantitative indicator of transverse crack density. However, it was noticed in practice that the residual thermal stresses resulting from the initial CFRP processing may pose a problem because the spectrum had already split into two peaks and became much broader before the tensile load was even apphed. Hence, this proposed baseline-free method could be used only if the FBG sensor could be embedded without the non-axisymmetric residual thermal stresses being present. Nonetheless, the direct measurement of actual strain with the FBG sensor can be used as abasehne-based method of inferring the crack density from the strain values, although this would have to rely on an initial baseline... 

For theoretical estimation of average a-relaxation times at different temperatures will employ derivative in research [1] and temperature dependence of o-relaxation times. Given the fact that cross-site chains of experimental objects have narrow molecular mass distribution, take average value = 0.5 as a spectrum width. 

Nearly isotropic. ) Nearly isotropic. ) hfs for two orthogonal crystal orientations with maximum and minimum total ) hfs for two crystal orientations with maximum total spectrum width and minimum spectrum width. value of H(a), respectively. ) hfs for crystal orientation with maximum total spectrum width. ") hfs for two orthogonal crystal orientations. ... 

F(l, CF2, CF3) coupling is a mean value obtained from the total spectrum width, assuming a small splitting for F(4). 

Liquids have their energy levels broadened due to the interaction of the closely packed atoms of the liquid. Such dense packing leads to an overlap of the electronic emission from various closely spaced rotational and vibrational levels, thereby producing emission spectrum widths of the order of to Hz. 

Abragam and Bleaney 1970). The calculated value of the spectrum width (solid curve in fig. 14b) is in a good agreement with the measured one. For comparison the results of a similar calculation with YES lattice parameters exceeding those mentioned above by only 2% are shown in the figure (dashed curve). 

The control measurement of gamma spectrum width in the system of "source Ca" " Sn03-resonant detector Ca" Sn03 without resonant screen." The rightmost point represents the average value. 

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