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Couplings spacing

Greater detail in the treatment of neutron interaction with matter is required in modem reactor design. The neutron energy distribution is divided into groups governed by coupled space-dependent differential equations. [Pg.211]

The ROESY spectrum of podophyllotoxin exhibits a number of crosspeaks (A-D) representing interactions between dipolarly coupled (space coupling) hydrogens, which can be helpful to determine the stereochemistry at different asymmetric centers. For example, based on the assumption that the C-1 proton (8 4.53) is /3-oriented, we can trace out the stereochemistry of other asymmetric centers. Cross-peak B represents dipolar coupling between the C-1 proton (8 4.53) and the C-2 proton (8 2.8), thereby confirming that the C-2 proton is also... [Pg.337]

Somljo It is within the measurement errors. There is a fenestration of the SR sheet, and sticking out come the caveolae. No one has really measured accurately this distance, or the distance between the caveolae and SR on top. The surface coupling space is pretty consistent. With regard to what is different in smooth muscle, if you are talking about the SR at the junction having Ca-ATPase or not, we don t know. What we do know from freeze-fracture studies of striated muscle is that the Ca-ATPase does not seem to be at the SR terminal cisternae. We don t know the answer in smooth muscle, but if there is Ca-ATPase at the junctional surface itself, this is different from what one sees in striated muscle. [Pg.45]

Future aspects of the study of electron kinetics based upon the electron Boltzmann equation certainly involve its extension to spatially two- and even three-dimensional kinetic problems, to coupled space- and time-dependent problems, to more complex field structures, and to more sophisticated boundary conditions. First attempts in these directions have already been undertaken in the literature (Meijer, 1991 Yand and Wu, 1996) or are on the way. [Pg.75]

FlG.l 1-17. Data of Fig, 11-16 reduced for the effect of temperature on entanglement coupling spacing, as measured by f, in addition to its effect on the local friction coefficient, as measured by... [Pg.309]

While with-in the mobile x-ray system, the waste in the sampler, is contained within a replaceable (and disposable) polyvinyl chloride (PVC) sleeve with a wall thickness of approximately 0.2-inches and a sealed bottom. It was anticipated that the PVC tube or sleeve would, with use, become highly contaminated with waste residues which drip of fall-off the sampler. The sleeve is coated with a conductive coating to prevent static electricity buildup . There are no sources of ignition in this sealed spare. The sampler (and waste) is coupling which includes a positive pressure gasket. This barrier is further isolated by a second barrier consisting of an epoxy coated aluminum sleeve also sealed-off from the main x-ray cabinet and PVC sleeve. There are also no potential sources of ignition in this isolated secondary space as well. [Pg.611]

Figure Al.2.7. Trajectory of two coupled stretches, obtained by integrating Hamilton s equations for motion on a PES for the two modes. The system has stable anhamionic synmretric and antisyimnetric stretch modes, like those illustrated in figrne Al.2.6. In this trajectory, semiclassically there is one quantum of energy in each mode, so the trajectory corresponds to a combination state with quantum numbers nj = [1, 1]. The woven pattern shows that the trajectory is regular rather than chaotic, corresponding to motion in phase space on an invariant torus. Figure Al.2.7. Trajectory of two coupled stretches, obtained by integrating Hamilton s equations for motion on a PES for the two modes. The system has stable anhamionic synmretric and antisyimnetric stretch modes, like those illustrated in figrne Al.2.6. In this trajectory, semiclassically there is one quantum of energy in each mode, so the trajectory corresponds to a combination state with quantum numbers nj = [1, 1]. The woven pattern shows that the trajectory is regular rather than chaotic, corresponding to motion in phase space on an invariant torus.
The question of non-classical manifestations is particularly important in view of the chaos that we have seen is present in the classical dynamics of a multimode system, such as a polyatomic molecule, with more than one resonance coupling. Chaotic classical dynamics is expected to introduce its own peculiarities into quantum spectra [29, 77]. In Fl20, we noted that chaotic regions of phase space are readily seen in the classical dynamics corresponding to the spectroscopic Flamiltonian. Flow important are the effects of chaos in the observed spectrum, and in the wavefiinctions of tire molecule In FI2O, there were some states whose wavefiinctions appeared very disordered, in the region of the... [Pg.76]

The central equations of electromagnetic theory are elegantly written in the fonn of four coupled equations for the electric and magnetic fields. These are known as Maxwell s equations. In free space, these equations take the fonn ... [Pg.219]

Other methods of sample introduction that are commonly coupled to TOP mass spectrometers are MALDI, SIMS/PAB and molecular beams (see section (Bl.7.2)). In many ways, the ablation of sample from a surface simplifies the TOP mass spectrometer since all ions originate in a narrow space above the sample surface. [Pg.1354]

On investigating a new system, cyclic voltannnetty is often the teclmique of choice, since a number of qualitative experiments can be carried out in a short space of time to gain a feelmg for the processes involved. It essentially pennits an electrochemical spectrum, indicating potentials at which processes occur. In particular, it is a powerfid method for the investigation of coupled chemical reactions in the initial identification of mechanisms and of intemiediates fomied. Theoretical treatment for the application of this teclmique extends to many types of coupled mechanisms. [Pg.1929]

For a coupled spin system, the matrix of the Liouvillian must be calculated in the basis set for the spin system. Usually this is a simple product basis, often called product operators, since the vectors in Liouville space are spm operators. The matrix elements can be calculated in various ways. The Liouvillian is the conmuitator with the Hamiltonian, so matrix elements can be calculated from the commutation rules of spin operators. Alternatively, the angular momentum properties of Liouville space can be used. In either case, the chemical shift temis are easily calculated, but the coupling temis (since they are products of operators) are more complex. In section B2.4.2.7. the Liouville matrix for the single-quantum transitions for an AB spin system is presented. [Pg.2099]

The Bloch equation approach (equation (B2.4.6)) calculates the spectrum directly, as the portion of the spectrum that is linear in a observing field. Binsch generalized this for a frilly coupled system, using an exact density-matrix approach in Liouville space. His expression for the spectrum is given by equation (B2.4.42). Note that this is fomially the Fourier transfomi of equation (B2.4.32). so the time domain and frequency domain are coimected as usual. [Pg.2104]


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Brillouin-Wigner coupled-cluster theory Hilbert space approach

Complete active space self-consistent fields coupled-cluster theory

Coupled Fock space

Coupled Isomerization Dynamics in Phase Space

Coupled cluster method active space

Coupled-cluster method Hilbert space approach

Coupled-cluster theory Fock-space

Couplings over More than Three Bonds and Through Space

Electronic coupling through-space interactions

Fock space multireference coupled-cluster

Fock space multireference coupled-cluster method

Fock-Space Coupled Cluster

Fock-Space Coupled Cluster Approach

Fock-space coupled cluster method

Fock-space coupled cluster method equations

Fock-space coupled cluster method ionization potentials

Fock-space multireference coupled cluster theory

Hilbert space approach, multi-root coupled cluster

Hilbert space approach, single-root coupled cluster

Long-range and through space coupling

Particle spaces strong coupling

Phase-space theory strong coupling

Single-root multi-reference Brillouin-Wigner coupled cluster theory Hilbert space approach

Spin-orbit coupling through-space

Through-space Scalar Coupling

Through-space coupling

Through-space spin coupling

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