Relaxation Filters

Because gravity is too weak to be used for removal of cakes in a gravity side filter (2), continuously operated gravity side filters are not practicable but an intermittent flow system is feasible in this arrangement the cake is first formed in a conventional way and the feed is then stopped to allow gravity removal of the cake. A system of pressure filtration of particles from 2.5 to 5 p.m in size, in neutralized acid mine drainage water, has been described (21). The filtration was in vertical permeable hoses, and a pressure shock associated with relaxing the hose pressure was used to aid the cake removal. 

Reactivity. Hemoglobin can exist ia either of two stmctural coaformatioas, corresponding to the oxy (R, relaxed) or deoxy (T, tense) states. The key differences between these two stmctures are that the constrained T state has a much lower oxygen affinity than the R state and the T state has a lower tendency to dissociate into subunits that can be filtered in the kidneys. Therefore, stabilization of the T conformation would be expected to solve both the oxygen affinity and renal excretion problems. 

This condition cannot be corrected on pumps with an enclosed impeller. You need to relax the restricted discharge flow on the pump. The problem could be a clogged downstream filter, a closed discharge valve, an over-pressurized header (back-pressurizing the pump), or a... 

Bottom filling should be used for nonconductive flammable liquids and filters should be placed at least three relaxation times upstream (5-3.4 and 5-3.5). The container should be grounded prior to opening and sealed prior to removing the grounding system. Filling rates should be similar to those... 

Table (a) shows experimental data [24] for the initial charge density exiting a fuel filter Qq plus the charge density Q remaining 30 s downstream. At low conductivity the charge decays much faster than predicted by an exponential relaxation law [Eq. (2-3.7)] and instead follows a hyperbolic relaxation law [24] given by... 

The basic experimental setup for etNOESY is practically identical to the conventional NOESY experiment shown in Eig. 9.2(B). For suppression of residual receptor signals a relaxation filter can be introduced and the mixing time has to be corrected according to the scaling factor a. 

This assumption can be relaxed when the experimental error in the independent variable is much smaller compared to the error present in the measurements of the dependent variable, In our case the assumption of simple linear least squares implies that Xvdt is known precisely. Although we do know that there are errors in the measurement of Xv, the polynomial fitting and the subsequent integration provides a certain amount of data filtering which could allows us to assume that experimental error in Jxvdt is negligible compared to that present in S(t,) or P(t,). 

The most fundamental aspect of a sensitivity discussion of remote detection is the fact that it is inherently a point-by-point technique. Each spectrum recorded by the detector does not contain any information other than its amplitude. Conceptually, a remote NMR experiment is very similar to a 2D NMR experiment with a z filter between encoding and detection, which causes all transverse magnetization to dephase. For 2D NMR experiments, it has been shown that the signal-to-noise ratio (SNR) per square root time, which will be denominated as sensitivity in the following, is the same as in the ID case when neglecting T2 relaxation [20, 21]. To compare the sensitivity of a remotely detected spectrum [Figure 2.6.4(b)] with an equivalent experiment with direct detection [Figure 2.6.4(a)], we can use an expression similar to the discussion in Ref. [20] ... 

A more complex but faster and more sensitive approach is polarization modulation (PM) IRLD. For such experiments, a photoelastic modulator is used to modulate the polarization state of the incident radiation at about 100 kHz. The detected signal is the sum of the low-frequency intensity modulation with a high-frequency modulation that depends on the orientation of the sample. After appropriate signal filtering, demodulation, and calibration [41], a dichroic difference spectrum can be directly obtained in a single scan. This improves the time resolution to 400 ms, prevents artifacts due to relaxation between measurements, and improves sensitivity for weakly oriented samples. However, structural information can be lost since individual polarized spectra are not recorded. Pezolet and coworkers have used this approach to study the deformation and relaxation in various homopolymers, copolymers, and polymer blends [15,42,43]. For instance, Figure 7 shows the relaxation curves determined in situ for miscible blends of PS and PVME [42]. The (P2) values were determined... 

Unavoidably, the efficiency of the different low-pass J filters in removing direct correlations induces attenuation of the signals associated with long-range couplings. For some molecules, the choice of the most suitable low-pass J filter may be first determined by the attenuation of those signals. Neglecting relaxation, pulse imperfections and offset effects, the... 

The results shown in Figure 8 are in good agreement with the theoretical results shown in Table 2. The value of the 2/c2hi coupling is very large, 49 Hz, and the attenuation during the respective low-pass J filters is subsequent (left). It must be pointed out that relaxation has not been... 

Figure 27 Edited broadband HMBC spectrum of cyclosporine using the pulse sequences shown in Figure 26 in an interleaved manner. The two subspectra, CH + CH3 (left) and C + CH2 (right), exemplify the editing properties. The spectrum in the bottom displays the two subspectra, CH + CH3 (black) and C + CH2 (grey) in the same frame. The number of scans was 32 for each of the 128fi increments, the relaxation delay was 1 s, and the range for the third-order low-pass. /-filter was 115 Hz < Vch < 165 Hz. The spectra were processed to maintain the absorptive profiles in F, while a magnitude mode was done in F2.

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