Non-synchronous rotation

The non-synchronous rotation of the two methylene groups implies a common transition state for both disrotatory and conrotatory ring opening, which may split into different transition states under the impact of a substituent. CASSCF/3-21G and CASSCF/6-31G(d) calculations lead to reaction energies which are far too negative (< -30 kcalmoT ) while UMP2/6-31G(d) predicts for this process a reaction energy of-20.2 kcalmoT in... 

The lag in the tidal response to Non-synchronous rotation causes a torque that tends to make the rotation synchronous, but that effect is counteracted in the case of an eccentric orbit. In the latter case, the lag in the diurnal tide yields a torque that varies over each orbit. The torque, averaged over each orbit, tends to drive the rotation to a rate slightly different from synchronous. That rate depends on details of the tidal response, but according to theory is expected to be only slightly faster than synchronous (Greenberg and Weidenschilling 1984). 

However, even a completely solid Europa would rotate non-synchronously as long as mass asymmetries are small enough. Non-synchronous rotation does not in itself imply the existence of an ocean. However, both the existence of an ocean and Non-synchronous rotation are made possible by the substantial tidal heating. 

More recently however, we have reviewed the evidence from azimuthal orientations, and have found that it may not be significant. Sarid et al. (2004) surveyed the rich record of cross-cutting features in the southern leading hemisphere and found no clear indication of Non-synchronous rotation. This issue is important, but at the current time is unresolved. 

The laminography method was developed initially for medical applications as a non-computer layer-by-layer visualization of the human body [1,2]. In this case an inclined initial X-ray beam projects an image of a specific layer of the object to the detector surface with defocusing of the other layers during a synchronous rotation of the object and the detector (Fig. 1). 

Another potential problem is due to rotor instability caused by gas dynamic forces. The frequency of this occurrence is non-synchronous. This has been described as aerodynamic forces set up within an impeller when the rotational axis is not coincident with the geometric axis. The verification of a compressor train requires a test at full pressure and speed. Aerodynamic cross-coupling, the interaction of the rotor mechanically with the gas flow in the compressor, can be predicted. A caution flag should be raised at this point because the full-pressure full-speed tests as normally conducted are not Class IASME performance tests. This means the staging probably is mismatched and can lead to other problems [22], It might also be appropriate to caution the reader this test is expensive. 

Sequential analysers. These instruments are reserved for non-routine elemental measurements. The detector and the crystal undergo simultaneous and synchronized rotations to ensure the detection of 6 and 26, to a precision of 1/1000 degree of an angle (Figure 12.13). 

Even given Europa s orbital eccentricity e, the rotation might be synchronous if a non-spherically symmetric, frozen-in density distribution (like that of the Earth s Moon) were locked to the direction of Jupiter. Given that Europa is substantially heated by tidal friction, it may not be able to support such a frozen-in asymmetry. It is also conceivable that the silicate interior is locked to the direction of Jupiter by a mass asymmetry, while the ice crust, uncoupled from the silicate by an intervening liquid water layer, rotates non-synchronously due to the tidal torque. 

The non-synchronous flow-through CPC is a particular type of planetary centrifuge which allows adjustment of the rotational rate of the coiled separation column at a given revolution speed. The first prototype was equipped with a dual rotary seal for continuous elution.Later, an improved modeP " was designed to eliminate the rotary seal which had become a source of complications such as leakage, contamination, and clogging. 

A non-synchronous centrifugal planetary coil system has also been reported (182, 376). This countercurrent apparatus is similar to that used for the synchronous mode of coil-CCC, but has the added sophistication of an adjustable revolution rate of the coil hence, the rate of revolution of the coil need not be synchronous to the rate of planetary rotation of the apparatus. (This method is occasionally referred to as planetary coil-CCC (PCCC).) Such flexibility is advantageous when the rate of coil revolution must be reduced to prevent emulsification of the two phases, which would result in transport of the stationary phase from the coil. This situation arises when there is low interfacial tension, as frequently occurs when separating macromolecules or partitioning intact cells with aqueous polymer phase systems. For instance, the nonsynchronous mode of centrifugal PCCC was successfully applied to the resolution of mammalian erythrocytes (183). This ability of aqueous solutions of two different polymers to form a two-phase liquid system allows for liquid-liquid partitioning between two aqueous phases (391). 

Phenol radical cations exist only in strong acidic solutions (pKa -1) [1, 2]. However, in non-polar media phenol radical cations with lifetimes up to some hundred nanoseconds were obtained by pulse radiolysis [3], The free electron transfer from phenols (ArOH) to primary parent solvent radical cations (RX +) (1) resulted in the parallel and synchroneous generation of phenol radical cations as well as phenoxyl radicals in equal amounts, caused by an extremely rapid electron jump in the time scale of molecule oscillations since the rotation of the hydroxyl groups around the C - OH is strongly connected with pulsations in the electron distribution of the highest molecular orbitals [4-6]. 

Leive, L. Cullinane, L.M. Groves, W. Improved non- 17. synchronous flow-through coil planet centrifuge without rotating seals. Principle and application. Sep. Sci. Technol. 

Figure 7.19 shows numerically calculated values of as a function of r for some values of C2, for each of which steadily rotating solutions are still stable. Note that the curves R versus r are rather insensitive to Ci. Combining this fact with (7.2.22) which expresses the amplitude dependence of the effective local frequency to, we see qualitatively how ib depends on r. We now realize that the system may be viewed as an array of radially coupled oscillators with a non-uniform distribution of the local frequencies d>(r). It is clear that increasing c2 makes the spatial gradient of o)(r) steeper especially in some regions near the core. The local oscillators will then find it more difficult to maintain mutual synchronization over the entire system. The resulting breakdown of the synchronization seems to be the cause of turbulence. 

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