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Phase of signal

Plenary 10. Hiro-o Hamaguchi, e-mail address lilrama ,chem.s.u-tokvo.ac.ip (time and polarization resolved multiplex 2D-CARS). Two-dimensional (tune and frequency) CARS using broadband dye source and streak camera timing. Studies dynamic behaviour of excited (pumped) electronic states. Follows energy flow within excited molecules. Polarization control of phase of signal (NR background suppression). [Pg.1218]

Baseline and phase correction are also important factors in determining the accuracy of the NMR result - it is usually the case that these have to be done manually to obtain best results. It is also quite likely that different operators will perform these functions differently and this may be a cause of reproducibility problems (see Section 4.4.5 below). A recent paper [199], though not aimed at quantitation directly, has a useful discussion of the difficulties of obtaining precise integrals, particularly with respect to the phasing of signals. [Pg.142]

The exact form of binding curves for multi-phase reactions such as this will be complex. Amongst other considerations, the relative amplitudes of the two phases of signal change will depend upon the position of the equilibrium between SpL and SpL. If SpL predominates then the amplitude of the slow change in fluorescence will be larger than if SpL predominates. Furthermore, the... [Pg.254]

Advanced signal processing techniques provides more elaborated approaches to the analysis and interpretation. In our study, we continue to promote the use of a continuous wavelet transform. We believe that its higher computational complexity are comparable to the Fourier transformation but the continuous wavelet transform makes the convenient assessment of amplitude, scale and phase of signal oscillations. Wavelet transform allows us to isolate a given structure in time and frequency space. Let us define the wavelet trans-... [Pg.46]

The phenomenon of chemically induced dynamic nuclear polarization (CIDNP) consists of the manifestation of unusual line intensities and/or phases of signals of radical reaction products in the NMR spectrum when reaction takes place directly in the probe of the spectrometer. These anomalous lines (enhanced absorption or emission of NMR signals), which reflect the populations of nuclear spin states deviating from the Boltzmann condition, are observed within the time range of nuclear relaxation times of the diamagnetic molecules (T, ), which are as a rule, several seconds to tens of seconds. Subsequently, the NMR spectrum re-acquires its usual form. In 1967, two research groups in Europe (J. Bargon, H. Fischer, and U. Johnson) and the USA (H. Ward and R. Lawler) discovered independently that this phenomenon is directly associated with the free radicals involved in the process. Later on, it was shown that this also pertains to radical ions and triplet excited states of molecules. [Pg.312]

At contact fatigue tests of different steel and cast iron types was used the acoustic emission technique. Processed records from the AE analyser show importance of acoustic response of tested surface continuous sensing. In graphs are obvious characteristic types of summation curves, or may be from significant changes of AE signal course identified even phases of the wear process. [Pg.66]

The computed CWT leads to complex coefficients. Therefore total information provided by the transform needs a double representation (modulus and phase). However, as the representation in the time-frequency plane of the phase of the CWT is generally quite difficult to interpret, we shall focus on the modulus of the CWT. Furthermore, it is known that the square modulus of the transform, CWT(s(t)) I corresponds to a distribution of the energy of s(t) in the time frequency plane [4], This property enhances the interpretability of the analysis. Indeed, each pattern formed in the representation can be understood as a part of the signal s total energy. This representation is called "scalogram". [Pg.362]

Moving the transducer along the concrete surface one is able to directly compare the data from different positions simultaneously reeieving information on intensity and phases of the signal and their relative changes. A Pentium-PC, included in tlie testing-system,... [Pg.752]

The calculations show that for both considered types of signals the CCF are very sensitive to initial phases of current and reference pulses and difference in their carrier frequencies. The CCF is also sensitive to the g-factor of loaded vibrators of probes and number of periods in the signal. [Pg.830]

Fig.3. CCF dependence on difference A(p = 0,25rc between initial phases of current and reference signals for s(t) type (left) and q(t) type of pulses. Fig.3. CCF dependence on difference A(p = 0,25rc between initial phases of current and reference signals for s(t) type (left) and q(t) type of pulses.
Correlative signal processing in MIA pulse flaw detectors is an effective way to increase the sensitivity and signal to noise ratio. Instruments with such processing system should be provided with a device for adjusting and sustaining initial phases of both current and reference pulses. [Pg.832]

A connnon teclmique used to enliance the signal-to-noise ratio for weak modes is to inject a local oscillator field polarized parallel to the RIKE field at the detector. This local oscillator field is derived from the probe laser and will add coherently to the RIKE field [96]. The relative phase of the local oscillator and the RIKE field is an important parameter in describing the optical heterodyne detected (OHD)-RIKES spectrum. If the local oscillator at the detector is in phase with the probe wave, the heterodyne mtensity is proportional to... [Pg.1208]

SFIG or SFG from a medium that has a strong response in a separate detection anu. By this means, one may fiilly compensate for variations not only in pulse energy, but also in the temporal and spatial substructure of the laser pulses. Some experiments may require measurement of the phase of the nonlinear signal [57]. [Pg.1281]

For higher accuracy, a method involving ampHtude modulation of a continuous laser beam is used. Again, a detector receives light reflected from the object where the distance is to be measured. The phases of the modulation in the outgoing beam and in the reflected return are compared. For a total phase shift A( ) between the two signals, the range R is... [Pg.14]

Figure 2 Micrographs of the same region of a specimen in various imaging modes on a high-resolution SEM (a) and (b) SE micrographs taken at 25 and 5 keV, respectively (c) backscattered image taken at 25 keV (d) EDS spectrum taken from the Pb-rich phase of the Pb-Sn solder (e) and (f) elemental maps of the two elements taken by accepting only signals from the appropriate spectral energy regions. Figure 2 Micrographs of the same region of a specimen in various imaging modes on a high-resolution SEM (a) and (b) SE micrographs taken at 25 and 5 keV, respectively (c) backscattered image taken at 25 keV (d) EDS spectrum taken from the Pb-rich phase of the Pb-Sn solder (e) and (f) elemental maps of the two elements taken by accepting only signals from the appropriate spectral energy regions.
Perhaps the most common use for REELS is to monitor gas—solid reactions that produce surface films at a total coverage of less than a few monolayers. When Eq is a few hundred eV, the surface sensitivity of REELS is such that over 90% of the signal originates in the topmost monolayer of the sample. A particularly powerfiil application in this case involves the determination of whether a single phase of variable composition occurs on the top layer or whether islands occur that is, whether... [Pg.327]


See other pages where Phase of signal is mentioned: [Pg.228]    [Pg.228]    [Pg.1218]    [Pg.228]    [Pg.357]    [Pg.112]    [Pg.113]    [Pg.356]    [Pg.382]    [Pg.634]    [Pg.228]    [Pg.228]    [Pg.1218]    [Pg.228]    [Pg.357]    [Pg.112]    [Pg.113]    [Pg.356]    [Pg.382]    [Pg.634]    [Pg.293]    [Pg.176]    [Pg.225]    [Pg.722]    [Pg.730]    [Pg.830]    [Pg.260]    [Pg.1281]    [Pg.1283]    [Pg.1561]    [Pg.1574]    [Pg.1598]    [Pg.1972]    [Pg.1990]    [Pg.611]    [Pg.326]    [Pg.129]    [Pg.376]    [Pg.231]    [Pg.417]    [Pg.613]    [Pg.567]    [Pg.227]    [Pg.227]    [Pg.367]   
See also in sourсe #XX -- [ Pg.43 ]

See also in sourсe #XX -- [ Pg.43 ]

See also in sourсe #XX -- [ Pg.43 ]




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