Synchronized fashion

The hydride transfer and the ring-opening of hexamethylenetetramine may occur in a synchronized fashion ... 

The gas-phase Diels-Alder reaction between butadiene and ethene follows a synchronous pathway, while the 1,3-dipolar cycloaddition of fulminic acid to ethyne proceeds in a concerted, almost synchronous fashion, in spite of the different nature of the two bonds closing the isoxazole cycle. 

The barrier to reactions in which two processes occur in a concerted (synchronous) fashion has been proposed to be approximately equal to the sum of the barriers to these individual steps in a fuUy stepwise reaction [(A -f B), Fig. 2.4(1)]... 

The orientation of the sample usually establishes the orientation of the goniometer axis, i.e. the axis around which both the detector and sample (or both the detector and x-ray source) rotate in a synchronized fashion during 0-20 or 0-0 data collection. A horizontal sample orientation implies that the goniometer axis is located in the horizontal plane, and a vertical sample orientation makes the goniometer axis vertical, as depicted in Figure 3.7. 

Powder diffractometer goniostats can be constructed in a way that both the detector and the sample revolve around a common goniometer axis in a synchronized fashion, or the sample is stationary, but both the detector and the x-ray source arms rotations are synchronized, as shown in Figure 3.10. When cylindrical samples are employed, generally there is no need in the synchronization of the goniometer arms, and only the detector arm (if any, e.g. see Figure 3.14, below) should be rotated. 

A different goniostat with the horizontal orientation of the specimen and Bragg-Brentano geometry is shown in Figure 3.13. The x-ray tube housing is mounted on the movable arm, and both the x-ray source and the detector can be rotated in a synchronized fashion about the common horizontal goniometer axis (also see the schematic in Figure 3.10, middle). 

The two-dimensional DQ MAS experiment can be performed in two distinct ways. We consider first spectra recorded in a rotor-synchronized fashion in t, i.e., the t increment is set equal to one rotor period, tr. In this way, all spinning sidebands in F can be considered to fold back onto the centerband position. The appearance of a rotor-synchronized 2D H DQ MAS spectrum is illustrated in Figure 8. Since the DQ frequency corresponding to a given DQC is simply the sum of the two SQ frequencies, DQCs between like (AA) and unlike (AB) spins can, in general, be distinguished in that, in the former case, a single peak at (2v, rA) is observed, while, in the latter case, two peaks at (rA + vb, v ) and (rA + vb, vb) are observed. [The notation (v, v2) refers to a DQ peak centered at rq and v2 in the / ) and F2 dimensions, respectively.]... 

Previous simulation results have enlightened two major observations first, the PNs and LNs which do not receive the stimulus remain silent while the others fire in a globally quasi-synchronized fashion, leading to LFP... 

There is some evidence that in the hydrolysis of compound LXV the two carboxylate groups act in a synchronous fashion. A bell-shaped pH-rate profile is observed, and even though at the maximum the rate is only 4X10 times faster than the diethyl ester, the compound with only one carboxyl group (LXVI) shows no evidence of intramolecular carboxyl participation intramolecular general acid catalysis only appears when the cationic centre has extra stabilisation [148]. 

In order for the cells to reach the chemotaxis-competent stage in a synchronized fashion, transfer them to an Erlen-meyer flask and shake them at 100 rpm for 1 h. Then pulse the cell suspension with 75 nM cAMP every 6 min for 4-6 h see Notes 6 and 7). 

Dewar [147,183,184] include zwitterionic forms together with the diradicals (model of the diradicaloids (Fig. 2), which considers the fact that most Diels-Alder additions, although being concerted, form the two new a bonds in a non-synchronous fashion in their transition states). Applied to 51 (and 43), this model predicts a para regioselectivity (52) for the Diels-Alder addition of methyl vinyl ketone due to favorable homoconjugative participation of the non-conjugated alkene moiety [185-189], as shown with the zwitterionic form 52. ... 

Sequential controls Sequential control functions perform real-time control of equipment to carry on a batch process to move a process through a succession of distinct states. An example of sequential control is opening a valve and running a pump for material transfer, material at any step, then after completing the step (may time controlled or quantity controlled) moves on to other step. Sequential controls in a batch process could he for major processes such as mixing, heating, and reaction. A phase may consist of a number of sequential control steps to manipulate equipment within a unit boundary. At time, it may be necessary that multiple units work in a synchronized fashion, for example, the transfer of material from one unit to another, with each unit having its own phase. Here, suitable communication between units is essential for synchronized operation. 

One could attempt to overcome this difficulty by using a three-electrode cell having one hydrogen electrode but two oxygen electrodes, one for oxygen evolution and the other for oxygen reduction, but in a multiceU battery, it would be difficult to switch over between the two sets of electrodes in aU the individual cells in a synchronized fashion. 

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