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Coupling break

SPX EFR generic events" (see tinnex 2) which correspond to non-quality of the equipment or fabrication plug left in an assembly leg, fan blade break, primary pump coupling break. [Pg.71]

For each of the following perturbations (disturbances) of this system at equilibrium, state whether you expect the coupling reaction shown in Model 3A to proceed to the right (forming more dance couples) or to the left (some couples break back into singles). [Pg.409]

While all contributions to the spin Hamiltonian so far involve the electron spin and cause first-order energy shifts or splittings in the FPR spectmm, there are also tenns that involve only nuclear spms. Aside from their importance for the calculation of FNDOR spectra, these tenns may influence the FPR spectnim significantly in situations where the high-field approximation breaks down and second-order effects become important. The first of these interactions is the coupling of the nuclear spin to the external magnetic field, called the... [Pg.1556]

Figure B2.4.5. Simulated lineshapes for an intennolecular exchange reaction in which the bond joining two strongly coupled nuclei breaks and re-fomis at a series of rates, given beside tlie lineshape. In slow exchange, the typical spectrum of an AB spin system is shown. In the limit of fast exchange, the spectrum consists of two lines at tlie two chemical shifts and all the coupling has disappeared. Figure B2.4.5. Simulated lineshapes for an intennolecular exchange reaction in which the bond joining two strongly coupled nuclei breaks and re-fomis at a series of rates, given beside tlie lineshape. In slow exchange, the typical spectrum of an AB spin system is shown. In the limit of fast exchange, the spectrum consists of two lines at tlie two chemical shifts and all the coupling has disappeared.
B2.5.351 after multiphoton excitation via the CF stretching vibration at 1070 cm. More than 17 photons are needed to break the C-I bond, a typical value in IR laser chemistry. Contributions from direct absorption (i) are insignificant, so that the process almost exclusively follows the quasi-resonant mechanism (iii), which can be treated by generalized first-order kinetics. As an example, figure B2.5.15 illustrates the fonnation of I atoms (upper trace) during excitation with the pulse sequence of a mode-coupled CO2 laser (lower trace). In addition to the mtensity, /, the fluence, F, of radiation is a very important parameter in IR laser chemistry (and more generally in nuiltiphoton excitation) ... [Pg.2131]

On short length scales the coarse-grained description breaks down, because the fluctuations which build up the (smooth) intrinsic profile and the fluctuations of the local interface position are strongly coupled and camiot be distinguished. The effective interface Flamiltonian can describe the properties only on length scales large compared with the width w of the intrinsic profile. The absolute value of the cut-off is difficult... [Pg.2373]

Non-adiabatic coupling is also termed vibronic coupling as the resulting breakdown of the adiabatic picture is due to coupling between the nuclear and electi onic motion. A well-known special case of vibronic coupling is the Jahn-Teller effect [14,164-168], in which a symmetrical molecule in a doubly degenerate electronic state will spontaneously distort so as to break the symmetry and remove the degeneracy. [Pg.276]

By following Section II.B, we shall be more specific about what is meant by strong and weak interactions. It turns out that such a criterion can be assumed, based on whether two consecutive states do, or do not, form a conical intersection or a parabolical intersection (it is important to mention that only consecutive states can form these intersections). The two types of intersections are characterized by the fact that the nonadiabatic coupling terms, at the points of the intersection, become infinite (these points can be considered as the black holes in molecular systems and it is mainly through these black holes that electronic states interact with each other.). Based on what was said so far we suggest breaking up complete Hilbert space of size A into L sub-Hilbert spaces of varying sizes Np,P = 1,..., L where... [Pg.663]

Study the making or breaking of bonds, and change of spin couplings (e.g. dissociation of II2)... [Pg.39]

The most noteworthy reaction of azo-compounds is their behaviour on reduction. Prolonged reduction first saturates the azo group, giving the hydrazo derivative (C NH-NH C), and then breaks the NH NH linkage, with the formation of two primary amine molecules. If method (1) has been employed to prepare the azo-compound, these two primary amines will therefore be respectively (a) the original amine from which the diazonium salt was prepared, and (6) the amino derivative of the amine or phenol with which the diazonium salt was coupled. For example, amino-azobenzene on complete reduction gives one equivalent of aniline, and one of p-phenylene diamine, NHaCeH NH benzene-azo-2-naphthoI similarly gives one equivalent of aniline and one of... [Pg.210]

Plasma torches and thermal ionization sources break down the substances into atoms and ionized atoms. Both are used for measurement of accurate isotope ratios. In the breakdown process, all structural information is lost, other than an identification of elements present (e.g., as in inductively coupled mass spectrometry, ICP/MS). [Pg.285]

Ce(IV)/Ce(III) couple may weU provide chemical assistance ia breaking up the silicate lattice. Transient formation of complexed groupiags consisting of. .Ce—O—Si., has been suggested. [Pg.370]

The full extent of the toxicity of pesticides to aquatic life is not known. Although chronic toxicity testing is required for new substances, little is known about the long-term effects of older pesticides. Also, very little is known about the toxicity and occurrence of the products formed when pesticides break down (metabolites) or the many non-pesticidal additives (co-formulants and adjuvants) used in pesticide formulations. However, the future is looking brighter. New modelling techniques, EQS development, and the involvement of the NRA in the pesticide registration process, coupled with the development of newer, less persistent pesticides with lower dose rates, all should help to reduce the risk of pesticide pollution. [Pg.56]


See other pages where Coupling break is mentioned: [Pg.190]    [Pg.193]    [Pg.193]    [Pg.319]    [Pg.420]    [Pg.54]    [Pg.375]    [Pg.478]    [Pg.497]    [Pg.193]    [Pg.383]    [Pg.333]    [Pg.36]    [Pg.112]    [Pg.87]    [Pg.190]    [Pg.193]    [Pg.193]    [Pg.319]    [Pg.420]    [Pg.54]    [Pg.375]    [Pg.478]    [Pg.497]    [Pg.193]    [Pg.383]    [Pg.333]    [Pg.36]    [Pg.112]    [Pg.87]    [Pg.74]    [Pg.74]    [Pg.957]    [Pg.1263]    [Pg.1459]    [Pg.2154]    [Pg.180]    [Pg.245]    [Pg.310]    [Pg.638]    [Pg.663]    [Pg.219]    [Pg.315]    [Pg.357]    [Pg.534]    [Pg.443]    [Pg.139]    [Pg.306]    [Pg.353]    [Pg.122]   
See also in sourсe #XX -- [ Pg.190 , Pg.193 , Pg.319 ]




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