Representative Spectra

Conclusive proof as to the survival of Si-H groups in HSi-PIB after cationic polymerization was obtained by H1 NMR analysis. To this end sufficiently low molecular weight samples were prepared (Mn = 600) and examined by H1 NMR spectroscopy. A representative spectrum is shown in Fig. 32. 

Figure 2 shows a representative XANES spectrum from a bulk gold sample (a 1 pm gold film) and a representative spectrum of gold reacted with oat biomass. 

The H Sn- C coupling constants observed in spectra in various solvents are given in Table I. A representative spectrum... 

Following this, attempts were made to remove a particle from the extruded plastic sheeting. When a particle was finally isolated, applying pressure with the ATR crystal resulted in cracking of the particle, so a representative spectrum could not be obtained. This brittle behavior usually indicates that the sample is inorganic in nature. 

Cathode surface-average Raman spectra were produced with the Raman microscope. Raman spectra were collected from multiple 52x75pm sections of the cathode surfaces at 0.7pm resolution and averaged into one representative spectrum for each cathode. MicroRaman surface-average spectra of the cathode from the virgin cell, and cathodes removed from cells,... 

Solid-state C variable-amplitude cross polarization magic-angle spinning (VACP/MAS) nuclear magnetic resonance (NMR) spectra were acquired for the sorbitol samples. Proton decoupling was achieved by a two-pulse phase modulation (TPPM) sequence. Identical C spectra were measured for the y-form sorbitol samples, and a representative spectrum is shown in Figure 9. 

IR SPECTRA. The IR spectra of all 10 samples derived from drinking water are almost identical. Figure 1 shows a representative spectrum. For comparison, the IR spectra of Satilla River aquatic humus and CFH are added. All samples exhibited broad bands in the 3400-cm 1 (—OH), 1720-cm"1 (C=0), and 1640-cm 1 (C=C) regions. However, the spectra from the 10 drinking water samples and CFH samples showed distinct differences from that of the Satilla River aquatic humus, which absorbs sharply near 1600 cm-1. This result suggests that the samples derived from drinking water are strongly altered by chlorination and/or oxidation. Further confirmation of the spectral dissimilarities should be pursued by analysis of chlorinated alteration products of humus. 

The intensities and wavelengths of spectral lines are characteristic of the emitting atoms or molecules. A representative spectrum is shown in Figure 2-1 this is the emission spectrum of atomic hydrogen,... 

A different, but no less severe problem, is encountered with the analysis of unknown biological substances by field desorption, laser desorption, and/or laser assisted field desorption mass spectrometry. A priori, it is not known at what point in time a component of interest is desorbed. This makes it difficult, if not impossible to time a scan or several scans in such a way that a representative spectrum is obtained. Again the answer to the problem is found by integrating the ion output over the entire sample or repeatedly over portions of the sample profile as it emerges from the ion source. 

Fig. 7. A representative spectrum of the unseparated product mixture from 101 MeV lsO+ 249Bk bombardments taken on a rotating wheel system. These data were recorded over a 20-s time interval starting 60 s after the end of collection. One should note the change of vertical scale at the center of the spectrum. Reprinted from [37] with the permission of Oldenbourg Verlag.

The contributions of this volume were presented at the meeting and selected for publication in Progress in Colloid and Polymer Science covering a representative spectrum of surface sensitive techniques and their application to polymer surface and thin film characterization as well as recent examples of technologically relevant materials and process development. 

Figure 16 Absorption spectrum of the cycfo-Mamb-Abu-Arg-Gly-Asp in D2O. The dashed line shows a representative spectrum of the pump pulses (width 12 cm-1) utilized to generate the 2D-IR spectra. (b,c) 2D pump-probe spectra of the same sample measured with the polarization of the probe pulse perpendicular and parallel to the polarization of the pump pulse, respectively. The dashed contour lines mark regions where the difference signal is negative (bleach and stimulated emission), while the solid contours lines mark regions where the response is positive (excited state absorption). The most prominent off-diagonal bands are marked by arrows. (d,e,f) A global least-squares fit of the experimental data, used to refine the coupling Hamiltonian in Equation (29c). (From Ref. 42.)...

The NIR spectrometer used for method development and sample analysis was a Foss NIR Systems Model 6500 Forage Analyzer with a sample transport module and a standard reflectance detector array. The transport module moves the sample compartment up and down during data collection, thereby allowing a more representative spectrum to be obtained from bulky heterogeneous samples. The reflectance array uses two silicon detectors to monitor visible light from 400-850 nm and four lead-sulfide detectors to monitor NIR light from 850-2500 nm. Natural product sample compartment cells in 1/4-cup and 1-cup sizes were used as sample holders in the transport module. This instrument has a maximum resolution of 2 nm. 

Figure 7 Ar matrix of Cr(CO)g doped with H2. Solid lines represent spectrum after broad band irradiation followed by irradiation through cobalt glass. Dashed bnes represent the spectrum of the same matrix after 90 min irradiation with the visible light from a Nemst glower. Band assignments 1, Cr(CO)5(H2) 11, Cr(CO)4(H2)2 III, Cr(CO)4(H2) 6, Cr(CO)6 5, CrjCOjs. (Reprinted with permission from Ref. 99. 1985 American Chemical Society)...

Fig. 3.4 (a) Representative spectrum from Anti-stokes/Stokes scattering experiment for the investigation of particle heating, (b) Comparison of the calculated AS/S ratio for the integrals of the peaks at —568 and 570 cm respectively. Error bars show one single standard deviation of the integrals of 10 spectra... 

A representative spectrum and assign- ments of chemical shifts are presented in Figure 3 and Table I23. 

FIGURE 4.5 Representative spectrum examples of SELDI analysis of pancreatic juice samples bound to IMAC-3 cupper ProteinChip array. A peak of 16,570 Da (arrow) was present in the four pancreatic juice samples from patients with pancreatic adenocarcinoma (PC4, PCS, PC 18, PC24) but absent in the four patients with other pancreatic diseases (IPMN islet cell tumor (ICT) serous cystadenoma (SC)). (Reprinted from Rosty et al. [26], used with permission from the American Association of Cancer Research.)... 

The other excitations are more classical and they correspond, for the first ones, to DisD2Po or DisD2P i pair states, where the electron of one of the neutral atoms of the pair makes a transition to a 2po or 2p state, with an energy distribution corresponding to the pair separation. A representative spectrum, where the contribution of donor pairs to the electronic absorption can be appreciated, is shown in Fig. 6.8. 

A representative spectrum of each peak in turn is examined, after background subtraction if necessary, and submitted to a library search. An experienced GC-MS analyst must interpret the validity of the library matches. If the library match is considered to be unequivocal, the identification is reported. If isomer specificity is not certain, but elemental composition is considered unequivocal the fit is reported without specific isomer identifiers. If the compound type is unequivocal, but specific compound identification is not possible, then the compound class is reported. If no library matches are considered to be reasonable, then the component is designated as unknown. Individual laboratories should always establish their own criteria for reporting compounds as positively identified. 

The investigations presented focus on interpretation of polarization of fluorescence measurements and use of these measurements to study the structure of a representative spectrum of linear synthetic polypeptides, a vinyl polymer, and an intramolecularly cross-linked synthetic polypeptide. The methodological studies investigate the validity of the transition temperature as a structural parameter, the interaction of the fluorescent dye and the polymer to which it is conjugated, and the influence of the dye-polymer interaction on the measurements of various molecular parameters. The structural studies focus on the structure of the random coil, the helix-coil transition, the a-helix to conformation transition in polylysine, and the stability of the spatial structure in intramolecularly cross-linked synthetic polypeptides. 

The investigations presented in this study focus on the interpretation of polarization of fluorescence measurements and the use of these measurements to study the structure of a representative spectrum of linear synthetic polypeptides, of polyvinylamine, and of a cross-linked synthetic polypeptide. 

The analysis of the metallic composition of the alloyed Au-Pd individual particles was carried out by acquiring EDX spectra from over 50 single particles and compared with the spectra from a large area of the catalyst. The overall spectrum and the representative spectrum from a single particle are shown in... 

Fig. 11.9 Mossbauer spectra for iron-carbon martensite. A is the field from iron atoms distant from carbon. The spectrum (ii) represents spectrum (i) with the A components subtracted. Fields B and C are from second- and first-nearest Fe neighbours respectively to the carbon atoms. D is paramagnetic austenite. [Ref. 89, Fig. 1]...

A representative spectrum of the data set is chosen. One typical representative is the mean vector x which has a corresponding wavelet coefficient vector W. However, other representative data vectors could have been used, e.g. the standard deviation or the first principal component. The choice will be dependent on the data set at hand. 

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