Dominance signals

For the characterisation of the biodegradation intermediates of C12-LAS, metabolised in pure culture by an a-proteobacterium, Cook and co-workers [23] used matrix-assisted laser desorption/ionisation (MALDI)-time of flight (TOF)-MS as a complementary tool to HPLC with diode array detection and 1H-nuclear magnetic resonance. The dominating signal in the spectrum at m/z 271 and 293 were assigned to the ions [M - H] and [M - 2H + Na]- of C6-SPC. Of minor intensity were the ions with m/z 285 and 299, interpreted to be the deprotonated molecular ions of C7- and C8-SPC, respectively. 

The use of ammonia for the protonation of nitroarenes leads frequently to formation of aduct ions, e.g. [M + NH4]+, but not to the protonated species (MH+)112,113. The ammonia chemical ionization spectrum of nitrobenzene shows, in addition to a series of adduct ions, a dominant signal corresponding to the anilinium ion (m/z 94)112114115. Evidence for the isomerization of the [M + NR ]"1" adduct followed by successive loss of NO and OH or NH3 to give ions corresponding to the substitution products, e.g. the anilinium ion, has been given115 see Scheme 41. 

X 11 X 20) mm. (a) Cross-section of the human lower leg of a volunteer. Two volume elements in musculature and one voxel inside the tibial bone marrow are indicated, (b) Spectrum recorded from the tibialis anterior (TA) muscle shows low lipid content of approximately 1% volume fraction, (c) Spectrum from the soleus (SOL) muscle indicates higher lipid content than in TA. (d) Spectrum from yellow bone marrow with dominating signal from fatty acids in triglycerides. 

Fig. 6. Expansion of the inverse detected 13C/103Rh HMQC NMR spectra of [Rh6(CO)15(P 4 p cgjj4j3)] one-dimensional projections showing the region of the bridging carbonyls. The spectra were obtained with defocusing delays of 17.9 ms 1/(2 JRh.c) a) and 7.14 ms (r 1/(5 /Rh,c), b), respectively. The expected correlations at the true 103Rh chemical shifts are clearly visible in the bottom spectrum, but are very weak or entirely absent in the top spectrum which displays correlations due to three-rhodium spin coherences as the dominant signals. Reproduced from Ref. 33 by permission of The Royal Chemical Society.

The solid-state hexamers (2)—(4) at first appeared to dissolve intact in benzene (94). Cryoscopic rmm measurements over a range of concentrations (0.03-0.09 M, molarity expressed relative to the empirical formula mass) implied n values of 5.9-6.1. Furthermore, their room-temperature 7Li NMR spectra in c/8-toluene each consisted of broad singlets within the narrow chemical shift (6) range of + 0.6 to -0.2 ppm (relative to external phenyllithium in the same solvent). However, variations in temperature and concentration affected the 7Li NMR spectra of (2) and, in particular, of (4) (95). Figure 18a shows these spectra for three d8-toluene solutions of (4) at -100°C. The most concentrated solution has a dominant signal at 8 -+0.7, though five or six other signals (indicated by asterisks) are apparent. On dilution,... 

Fig. 1. MALDI-TOF mass spectrum of an antibacterial peptide isolated from dog Canis familiaris using the CHCA matrix. The dominant signals at m/z 4190.38 and 2095.68 correspond to the [M+H]+ and [M+2H]2+ ions of the same peptide. The doubly charged ion, which is usually not obtained for peptides in MALDI-MS, is probably detected due to the high content of basic lysine and arginine residues.

Ayasse M., Maelovits T., Tengo J., Taghizadeh T. and Francke W. (1995). Are there pheromonal dominance signals in the bumblebee Bombus hypnorum L. (Hymenoptera, Apidae) Apidologie, 26,163-180. 

ESI mass spectra after the addition of 49 (or 50) to 51(PF6)2 show the hexameric clusters 51 (49)6 and 51 (50)6 as the dominating signals (Figure 3.24). These ions were irradiated in an infrared multiphoton dissociation experiment (I RMPD) with IR radiation from a C02 laser at different time intervals. The observed fragmentation behavior was exactly that expected for the hexameric capsule. 

It is believed that nonlinear optical photonic crystals, which can bend and amplify elected photons (wavelengths) of light, will dominant signal-processing technology after the electronics era. This, combined with the intriguing properties of matter at the nanoscale, has made nano-optics an active research held. 

Fig. 10. One-dimensional phasing depth images for southern Africa, organized by geological province. The munber of events included in the stack and the station name are shown to the right of each trace. The dominant signal on most of the depth images shown is the Ps conversions from the Moho. Relatively thin (35-40 km) crust and sharp, well-defined Ps Moho conversions are associated with undisturbed craton. Ps arrivals associated with modified regions of the craton and post-Archaean terranes tend to be more diffuse and of smaller amplitude (from Nguuri et al. 2001, published in GRL28, 2001, fig,. 2).

The basic imaging methods of NMR are applicable primarily to imaging of liquids and soft matter, where lines are narrow and spectral dispersion is small compared to the frequency dispersion introduced by application of magnetic-field gradients. The primary incentive for development of these methods comes from applications in medicine and biology, where the dominant signal is most often from water [Andl, Call, Cerl, Kiml, Mori, Vial, Wehl,Weh2]. 

Fig. 1 Theoretical proposed representation of the signal to noise in the cortical networks as affected by propranolol, based upon the findings of Hasselmo et al (1997) on the effects of norepinephrine in the cortex. Black arrows indicate a greater response to the most dominant signal input, such as representation of an attended stimulus, which may be suppressed by noradrenergic blockade. White arrows indicate the response to nondominant signal input, such as intrinsic or associative fiber inputs, the noise in the model, which may increase with noradrenergic blockade, proposed to be how problems without an immediately accessible answer may be solved more readily in this condition or how patients with impaired flexibility of network access may benefit in a more general manner in this condition.

In comparison to SWNTs, MWNTs give rise to a much more graphite-like Raman spectrum with a dominant signal at ca. 1575 cm" and a weaker one at about 868cm" . The determination of stmctural properties from the Raman spectra of MWNTs is anything from complicated to impossible due to the variety of constituent tubes and their respective interactions. 

The powder X-ray diffractograms of the AlTUD-1 and [WLJ-TUD reveal that the modified sample has structural characteristics identical to the matrix, showing that the the immobilization process did not cause any change in the structure of the support. Both XRD patterns shows one dominant signal, an intense peak around 0.70° 0, indicating the AlTUD-1 is a mesostructured material [17]. 

The observed mass spectrum reported by Basner et al. (1998, 1999) agrees in its general features with the published data in the standard mass spectrometric data bases. However, the Eight Peak Index (1974) contains 10 different mass spectra with distinct differences. Table V lists the various ions, their relative intensities at 70 eV impact energy, their appearance energies, and the total and partial cross sections at 70 eV (Basner et al., 1998 Basner et al., 1999 Foest, 1998). The ionization energy of the HMDSO molecule is 8.8 1.3 eV The ion spectrum produced by 70-eV electron impact on HMDSO is characterized by a dominant signal at w/z = 147, which results from the dissociative ionization of... 

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