Step-up ratio

The literature contains [19] impressive performance data for multilayer transformers, made more impressive by the low sintering temperature (960 °C) of the PZT fluxed with small amounts (3 wt.%) of mixes of B203, Bi203 and CdO. Open circuit voltage step-up ratios as high as 9000 are claimed. 

The high voltage transformer has an effective primary to secondary step-up ratio of 11 to 1. The maximum a.c. current that can be drawn from the secondary winding of the transformer is 60 milliamperes r.m.s. 

The mild cleavage conditions with NEt3 HF, which do not cause epimerization at centers a to the carbonyl group, are essential for an enantioselective synthesis of y-oxoesters using optically active catalysts 641 in the cyclopropanation step. Up to 50 % ee have been obtained so far 65). Improvements should be possible, if the trans/cis-ratio of the siloxycyclopropane can be increased. Formylesters of type 99 are promising building blocks for further transformations (e.g. synthesis of y-butyrolactones). 

One can note that for this step the ratio of reagents 3 2 is 2 1, the excess diamine, 3, playing the role of base which takes up the hydrogen chloride liberated by the coupling reaction. The separation of the monocyclic diamide 4 from the reaction mixture containing amide oligomers is easy as the latter... 

The 800 nm transition from 3H4 to 3H6 has been extensively studied because of its suitability for optical amplification in the first telecommunication window. With a branching ratio of 90%, this transition is not perturbed by amplified spontaneous emission of competing transitions. The 1.47 jum emission from 3H4 to 3F4 is also of special interest for optical amplification between the second and third telecommunication window. Both transitions arise from the 3H4 level, which can be excited directly at 800 nm with a laser diode. This level can also be pumped by 2-step up-conversion, either from a mini-YAG Nd at 1.06 m or from a laser diode at 975 nm, in (Yb, Tm) codoped glasses. Details on these applications are given in Sec. 8.5.2. 

Independently of their nature, attractant and repellent stimuli are integrated by the cell if applied simultaneously [25,40]. For example, a blue step-up (repellent) stimulus can be repressed in its repellent action by a green step-up (attractant) stimulus, provided an appropriate intensity ratio of both light colours is applied. Integration was also demonstrated for a symmetrically inverted stimulus program, i.e. a blue step-down... 

Comment 2 Suppose that our feed composition had been a little higher, say xp. No matter how many steps we took, we could never get a liquid composition higher than that at the intersection of the operating and equilibrium curves. In that case, any solution for the specified L/V ratio is impossible. Instead the L/V ratio would have to be decreased, which will rotate the operating line clockwise about the specified point. This will raise the liquid composition at the intersection point and make the separation possible. It turns out there exists maximum L/V, or a minimum vapor rate V which allows a particular bottoms composition xp to be produced from a given feed composition xp and liquid flowrate L. This minimum V/L is called the minimum boil-up ratio. 

The results reported in Figs. 6.11, 6.12, 6.13, 6.14, 6.15, 6.16, and 6.17 [3] refer to experiments perfonned using a series of power steps up and down, each of them characterized by a rate of about 150 W/s. The Fig. 6.11 shows stack power, stoichiometric ratio, and temperature acquired as a function of time, whereas the coefficient of variation Cy related to individual cells is reported in Fig. 6.12. 

FC data set at 30 Larmor frequencies and two director orientations makes use of more than 50 Ti v pairs at one constant temperature to find, by iterative steps, up to 11-14 unknown quantities. It is evident that not all the model characteristics could be evaluated reliably because of very strong correlations in the fitting process. In particular the fitting of both OF-mode cut-off frequencies of the anisotropy ratios trand e, and of the jump length parameter a, proved rather insensitive near physically plausible constraints. Some results obtained in this way are listed in Table 1 to illustrate differences between 5CB and 8CB. These data have been interpreted with astonishing success by means of the molecular geometry, i.e. by spin-pair orientations and separations, and available visco-elastic material constants, i.e. 

In the next step, the ratio of the two components has to be taken into account. If the disorder does not involve any special positions, the occupancies of both components are allowed to possess any ratio. It is important, however, that the site occupancy factors (sof) sum up to exactly one. 

We will now use dimensional interpolation to proceed from the known results, namely those at low n, at low B, and at high B, to the desired results at higher n and at D = 2 or D = 3. The interpolation will actually be performed on the cluster integral ratios p nk] D), since these quantities had finite but non-zero dimensional limits. Given interpolated ratios, one can simply step up from the known integrals for hard points or rods to those for hard disks or spheres (or even higher-dimensional fluids), since... 

We need to discuss some of the limiting conditions in distillation systems. The minimum number of trays for a specified separation corresponds to total reflux operation. If the column is mn under total reflux conditions, the distillate flow rate is zero. Therefore, the reflux ratio is infinite, and the slope of the operating lines is unity. This is the 45° line. Thus, the minimum number of trays can be determined by simply stepping up between the 45° line and the VLB curve (see Fig. 2.8). 

Step up transformers are used to increase the output voltage. The electricity generated in a power-station is stepped up for distribution on the National Grid network. Figure 2.58 shows a step up transformer where the primary winding has only half the number of turns as the secondary winding. The turns ratio is 1 2 and, therefore, the secondary voltage is doubled. 

F(t) is a probability distribution which can be obtained directly from measurements of the system s response in the outflow to a step-up tracer input in the inflow. Consider that at time t = 0 we start introducing a red dye at the entrance of the vessel into a steady flow rate Q of white carrier fluid. The concentration of the red dye in the inlet flow is C. At the outlet we monitor the concentration of the red dye, C(t . If our system is closed, i.e. if every molecule of dye can have only one entry and exit from the system (which is equivalent to asserting that input and output occur by convection only), then QC(t)/QCQ is the residence time distribution of the dye. This is evident since all molecules of the dye appearing at the exit at time t must have entered into the system between time 0 and time t and hence have residence times less than t. Only if our red dye is a perfect tracer, i.e.. if it behaves identically to the white carrier fluid, then we have also obtained the residence time distribution for the carrier fluid and F(t) = C(t)/C. To prove that the tracer behaves ideally and that the F curve is obtained, the experiment should be repeated at different levels of C. The ratio C(t)/C at a given time should be invariant to C, i.e. the tracer response and tracer input must be linearly related. If this is not the case, then C(t)/CQ is only the step response for the tracer, which includes some nonlinear effects of tracer interactions in the system, and which does not represent the true residence time distribution for the system. 

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