Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Divider step response

Figure 23 Calculation of the shape of the actively compensated pulse can be carried out on the software. (A) shows the real (red line) and the imaginary (green line) component of an example of the target pulse shape t>,(f). Its leading and the trailing edges have a cosine shape with a transition time of 1.25 xs in 50 steps, and the width of the plateau is 5 ps. (B) Laplace transformation B(s) multiplied by the Laplace transformed step function U(s). (C) It was then divided by the Laplace transformation Y(s) of the measured step response y(t) of the proton channel of a 3.2-mm Varian T3 probe tuned at 400.244 MHz to obtain V(s). (D) Finally, inverse Laplace transformation was performed on V(s) to obtain the compensated pulse that results in the RF pulse with the target shape. Time resolution was 25 ns, and o = 20 was used for the Laplace and inverse Laplace transformations. Figure 23 Calculation of the shape of the actively compensated pulse can be carried out on the software. (A) shows the real (red line) and the imaginary (green line) component of an example of the target pulse shape t>,(f). Its leading and the trailing edges have a cosine shape with a transition time of 1.25 xs in 50 steps, and the width of the plateau is 5 ps. (B) Laplace transformation B(s) multiplied by the Laplace transformed step function U(s). (C) It was then divided by the Laplace transformation Y(s) of the measured step response y(t) of the proton channel of a 3.2-mm Varian T3 probe tuned at 400.244 MHz to obtain V(s). (D) Finally, inverse Laplace transformation was performed on V(s) to obtain the compensated pulse that results in the RF pulse with the target shape. Time resolution was 25 ns, and o = 20 was used for the Laplace and inverse Laplace transformations.
Next, bi(t) was Laplace transformed into B(s), and then multiplied by the Laplace transformation U(s) of the step function u(t). The result B(s)U(s) is displayed in Figure 23B. In this example, the step response y(t) was measured for the 1H channel of a Varian 3.2 mm T3 probe tuned at 400.244 MHz with a time resolution of 25 ns, and Laplace transformed into Y(s). By dividing B(s)U(s) by Y(s), the function plotted in Figure 23C was obtained, from which, by performing inverse Laplace transformation, the programming pulse shape v(t) was finally obtained, as shown in Figure 23D. The amplitude and the phase of the complex function v(t) give the intensity and the phase of the transient-compensated shaped pulse. [Pg.390]

Since the step response (F curve) is the time integral of the pulse response (C curve), the Laplace transform of the step response for the general boundary conditions as used by van der Laan will be given by dividing equation (27) by the transform variable, p,... [Pg.118]

Pulse or time domain ESR can be divided into two categories the transient response of spin systems to abrupt or step changes in resonant condition and the transient response to sequence of pulses [20]. The step response, as in saturation recovery, is used commonly to measure T, and the pulse response, as in 90-180° spin echo, to measure Tj. [Pg.139]

The dielectric relaxation techniques can be sub-divided into two groups step response or continuous wave methods,... [Pg.108]

The settling time of the first step response is estimated to be approximately 200 sec and therefore the search interval for the optimal time scaling factor p is chosen to be (2U0 interval is divided into 17 discrete values... [Pg.51]

Dynamically, the response of hquid temperature to a step in steam flow is that of a distributed lag, shown in Fig. 8-48. The time required to reach 63 percent complete response, X "t, is essentially the residence time of the fluid in the exchanger, which is its volume divided... [Pg.746]

The behavior predicted by this equation is illustrated in Fig. 16-33 with N = 80. Xp = (Evtp/L)/[il — )(p K -i- )] is the dimensionless duration of the feed step and is equal to the amount of solute fed to the column divided by tne sorption capacity. Thus, at Xp = 1, the column has been supplied with an amount of solute equal to the station-aiy phase capacity. The graph shows the transition from a case where complete saturation of the bed occurs before elution Xp= 1) to incomplete saturation as Xp is progressively reduced. The lower cui ves with Xp < 0.4 are seen to be neany Gaussian and centered at a dimensionless time - (1 — Xp/2). Thus, as Xp 0, the response cui ve approaches a Gaussian centered at Ti = 1. [Pg.1534]

Cellular defense mechanisms against toxins (A multistep mechanism for elimination of toxic metabolites and xenobiotics. It involves various transport, oxidation, and conjugation steps.) are usually divided into several steps as it is visualized on Fig. 3. Organic anion transporting proteins (OATPs) are responsible for the cellular uptake of endogenous compounds and... [Pg.750]

The study of isotopes makes it necessary to introduce a further refinement in the general method of solution. I have been using a test of the relative increment to adjust the time step. The relative increment is the change in a dependent variable divided by the value of that variable. This is not a useful test, however, when the value of the variable approaches zero, because the test requires progressively smaller time steps. None of the variables I considered in previous chapters has approached zero, and so there has been no problem with this test. But carbon isotope ratios of seawater have delta values near zero, and a problem may occur when calculating these values. I have modified subroutine CHECKSTEP to permit a flexible response to this situation. [Pg.81]

Because estrogenic mycotoxins usually occur at microgram per kilogram (pg/kg) levels there is special interest in analytical procedures for reliable detection of zearalenone and its metabolites between 10 and 100 pg/kg. In response to the risk of a great economic loss to the industry and the threat to human health as a result of exposure to zearalenone, several methods have been developed for the quantification of zearalenone and its metabolites in different foods, feeds, animal tissues, blood and urine. Detailed reviews have been given by Steyn et al. 1991 Betina 1993 Frisvad and Thrane 1993 Scott 1993 Steyn 1995 and Lawrence and Scott 2000. The determination of zearalenone in cereals can be divided into five steps grinding of the sample, extraction of the sample, clean-up, separation and detection. [Pg.423]

Ary given catalytic material can be abstracted based on the same underlying similar architecture — for ease of comparison, we describe the catalytic material as a porous network with the active centers responsible for the conversion of educts to products distributed on the internal surface of the pores and the external surface area. Generally, the conversion of any given educt by the aid of the catalytic material is divided into a number of consecutive steps. Figure 11.13 illustrates these different steps. The governing transport phenomenon outside the catalyst responsible for mass transport is the convective fluid flow. This changes dramatically close to the catalyst surface from a certain boundary onwards, named the hydrodynamic boundary layer, mass transport toward and from the catalyst surface only takes place... [Pg.391]

As in other areas of natural products chemistry, studies on insect chemical defenses comprise several different aspects first come the isolation and structure determination of the compound(s) responsible for the defensive activity. The next step is the total synthesis of the identified compounds, in order to confirm the proposed structure, usually deduced from spectroscopic data only, and to get enough material for biological testing. Biosynthetic studies to determine the origin of the active compound(s) (biosynthesis by the insect itself or sequestration from the diet with or without metabolization) are sometimes performed. In some cases, the biological activities of the isolated compounds (repellency, toxicity...) and their possible pharmacological activities are also evaluated. This chapter is divided into four sections treating those different topics. [Pg.181]

Adjust dosage in 2.5 to 5 mg increments, as determined by blood glucose response. Several days should elapse between titration steps. If response to a single dose is not satisfactory, dividing that dose may prove effective. The maximum recommended once daily dose is 15 mg. The maximum recommended total daily dose is 40 mg. [Pg.308]

Because so many factors determine the response obtained for a chemical substance in a sample, it is usually not possible to derive directly the concentration from the measured response. The relationship between signal, or response and concentration has to be determined experimentally, a step which is called calibration. The complexity of the calibration depends upon the type of expected problems. These are roughly divided into three categories interferences, matrix effects or interactions and a combination of both, a so-called interacting interference. [Pg.33]

Subject to silylation (steps 15 to 17) and analyze (steps 18 to 20). Analyze data 23. Divide the area ratio of cholesterol in the samples by that of the internal standard to obtain a standard response ratio. 24. Plot the average response ratio against the ratio of cholesterol to internal standard in the standards. [Pg.456]

Caspase activation occurs as a late and common step in all cells undergoing apoptosis. Nevertheless, there are many initial pathways that can result in caspase activation. Probably, each distinct pathway is triggered by different apoptotic stimuli. In mammalian cells, the apoptotic response is usually mediated by the intrinsic and extrinsic pathways, depending on the origin of the death signal. The intrinsic pathway can further be divided into mitochondrial and ER stress pathways. [Pg.162]


See other pages where Divider step response is mentioned: [Pg.228]    [Pg.255]    [Pg.242]    [Pg.451]    [Pg.729]    [Pg.201]    [Pg.136]    [Pg.102]    [Pg.254]    [Pg.264]    [Pg.50]    [Pg.107]    [Pg.100]    [Pg.514]    [Pg.36]    [Pg.142]    [Pg.319]    [Pg.1215]    [Pg.1215]    [Pg.1890]    [Pg.21]    [Pg.314]    [Pg.154]    [Pg.322]    [Pg.1219]    [Pg.353]    [Pg.245]    [Pg.40]    [Pg.88]    [Pg.263]    [Pg.487]    [Pg.150]    [Pg.169]   
See also in sourсe #XX -- [ Pg.65 ]




SEARCH



Divide

Divider

Step response

© 2024 chempedia.info