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Decoupling definition

There has been considerable discussion about the extent of hydration of the proton and the hydroxide ion in aqueous solution. There is little doubt that this is variable (as for many other ions) and the hydration number derived depends both on the precise definition adopted for this quantity and on the experimental method used to determine it. H30" has definitely been detected by vibration spectroscopy, and by O nmr spectroscopy on a solution of HF/SbFs/Ha O in SO2 a quartet was observed at —15° which collapsed to a singlet on proton decoupling, 7( 0- H) 106 Hz. In crystalline hydrates there are a growing number of well-characterized hydrates of the series H3O+, H5O2+, H7O3+, H9O4+ and H13O6+, i.e. [H(0H2) ]+ n = 1-4, Thus... [Pg.630]

From the evidence discussed above, the framework of methylkasugaminide is determined to be methyl 2,4-diamino-2,3,4,6-tetradeoxyhexo-pyranoside in which hydrogens at C-4 and C-5 are axial-axial and hydrogens at C-l and C-2 are not in axial-axial relation. The structure was definitely proved by the application of the spin decoupling technique and, moreover, the relative relations of all hydrogens were confirmed. [Pg.28]

Retracing the argument used to justify point (2), it is clear that, in a multiply connected space, a given path is only coupled to those paths into which it can be continuously deformed. By definition, these are all the paths that belong to the same homotopy class. Paths belonging to different homotopy classes are thus decoupled from one another [41 5]. For a reactive system with a Cl that has the space of Fig. 1, this means that a path with a given winding number n is coupled to all paths with the same n, but is decoupled from paths with different n. As a result, the Kernel separates into [41-45]... [Pg.11]

Figure 10.13. A decoupled control scheme. The controller outputs are the manipulated variables in Eqs. (10-38) and (10-39) and they are rewritten based on their definitions in (10-25) and (10-28). [Pg.208]

The above definition of the enthalpic effects of conjugation is not unique. A second definition decouples the two double bonds by an alternative hydrogenation process (equation 19). [Pg.76]

Packages are built by importing other packages and by extending the imported definitions (Section 7.2). This import facility can be used to effectively partition development work in several useful ways (Section 7.3) as well as to decouple units of work from changes in others (Section 7.4). [Pg.310]

Let s look at two issues that arise with the use of encapsulation in packages model decoupling with auxiliary definitions and the use of encapsulation in specifications. [Pg.335]

Model Decoupling with Encapsulated Auxiliary Definitions... [Pg.335]

To define the two-stage algorithm we will follow the work of Valko and Vadja (1987), which basically decouples the two problems. Starting from the definition of the general EVM problem in Eq. (9.22), the vectors zi,..., %u minimize the constrained problem at fixed 0, if and only if each Zj, j = 1,2,..., M, is the solution to... [Pg.187]

The radial momentum equation is decoupled from the rest of the system, but can be used to determine the radial pressure gradient if needed. Again, substituting the scaled axial velocity and other definitions yields... [Pg.300]

The complete structure of schelhammerine (except for stereochemistry at C-2 and C-5) was deduced as 80a from a careful analysis of its 100-MHz NMR spectrum, with the aid of decoupling experiments. Values of 5.0 Hz for J3,4eq and 3.2 Hz for /3>4ax suggested that the proton at C-3 was equatorial but a value of 3.0 Hz for J2A did not allow definitive assignment of the stereochemistry at C-2, although it suggested that the proton at C-2, was also equatorial. The absolute stereochemistry (as shown in 80a) was established by X-ray analysis of schelhammerine hydrobromide (92). [Pg.33]

Varian uses the decoupler mode (dm) parameter to determine when the decoupler should be turned on and off during the pulse sequence. Time periods A, B, C,. .. are defined during any pulse sequence, and the definition of these time periods can be observed by entering dps (display pulse sequence). For the general ID sequence called s2pul (simple 2-pulse), the periods A, B, and C are defined as follows ... [Pg.154]

If delayed extraction increases the mass resolution without degradation of sensitivity compared with continuous extraction, it also has limitations. Indeed, delayed extraction complicates the mass calibration procedure. It can only be optimized for part of the mass range at a time and is less effective at high mass. Delayed extraction partially decouples ion production from the flight time analysis, thus improving the pulsed beam definition. However, calibration, resolution and mass accuracy are still affected by conditions in the source. For instance, in the usual axial MALDI-TOF experiments, optimum focusing conditions depend on laser pulse width and fluence, the type of sample matrix, the sample preparation method, and even the location of the laser spot on the sample. [Pg.131]

The problem is conventionally sidestepped by assuming that nuclear and electronic motions are decoupled, but despite many efforts this condition has never been shown to yield a rigid molecular shape either. The insurmountable problem is permutational invariance. In molecular-orbital calculations that decouple electronic from nuclear motion the nuclei are identified in order to support the definition of molecular structure, but then permutation of identical nuclei implies rearrangement of bonds and a new set of calculated electronic energies. There is little hope of ever overcoming these problems ... [Pg.200]

The dipolar interaction and CSA contribute to i7 22K,iT-iK,iTiK,iT2-2K> but not to Hoo. On the contrary, the isotropic chemical shift contributes only to iToo-Hence, in order to achieve zero-order decoupling, all the terms in Eq. 73 must vanish, except iToo- This can be accomplished when, according to the definition of... [Pg.64]

In the EH-CSD approach it is not convenient to decouple electrostatic terms into rigid Coulombic and polarization contributions the effective Hamiltonian leads to compute these two terms together. Exchange repulsive terms are hardly computed when the second partner of the interaction is a liquid they may be obtained with delicate simulation procedures, and it is convenient to decouple them into two contributions, namely the work spent to form a cavity of a suitable shape and an additional repulsion contribution. Dispersion contributions may be kept we shall examine this term in more detail later. Charge-transfer contributions are damped in liquids their inclusion could introduce additional problems in the definition of Vjnt via continuous solvent distributions. It is advisable to neglect them, as it is done in the interaction potentials used in simulations with the present approach it is possible to describe the charge transfer effect by enlarging the solute M —> M-Sn. [Pg.6]

TITLE Kinetic decomposition of sodium acetate definition of Methane decouples C02 and CH4... [Pg.245]


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See also in sourсe #XX -- [ Pg.34 ]




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