Orientational alignment

As stated earlier, when placed in a magnetic field, the hydrogen nuclei adopt one of two different orientations, aligned either with or against the... 

We have shown that redox chromophores organized in LB films with resped to their orientation, alignment, or electronic interactions make very useful and specific photoresponses such as amplified fluorescence quenching, photocurrents controlled at the molecular level, photoinduced anisotropic eledrochromism, and photochemically modulated second harmonic generation. These results may contribute to facilitate the design and construction of novel photonic devices in the near future. 

Sholklapper et al. [204] studied the structure and performance stability of a nanoparticle-infiltrated LSM in porous scandia-stabilized zirconia (SSZ) electrode at 650°C. The infiltrated LSM particles were 100 nm in diameter and some orientation alignment of the LSM nanoparticles within SSZ was observed after the cathodic polarization at 150 mAcnr2 for 500 h. However, there is no voltage degradation under the conditions studied. 

For molecular desorption, laser spectroscopic studies of the desorbing molecule can give full internal state distributions, Df Ef, 6f, v, J, f M ), Ts), where f M ) is some distribution function describing the rotational orientation/alignment relative to the surface normal. For thermal desorption in non-activated systems, most atoms/molecules have only modest (but important) deviations from a thermal distribution at Ts. However, in associative desorption of systems with a barrier, the internal state distributions reveal intimate details of the dynamics. Associative desorption results from the slow thermal creation of a transition state, with a final thermal fluctuation causing desorption. Partitioning of the energy stored in V into... 

NMR depends on magnetic properties of atoms and their nuclei, where magnetic nuclei orient/align parallel to (with) or anti-parallel to (against) the external magnetic field. 

Cholesteric liquid crystals are optically active nematic phases as a result of their gradual twist in orientational alignment. Therefore, cholesteric liquid-crystalline solvents are expected to induce enantioselectivity in chemical reactions see reference [713] for a review on photoasymmetric induction by chiral mesophases. The existing results are not very promising. So far, the maximum photoasymmetric induction reported has... 

The orientation of anisotropic particles during dip coating can be analyzed by considering the rotational diffusion of these particles in shear. Rotational diffusion in shear flow has been reviewed by Van de Ven [58]. The ratio of the shear rate, y, to the rotational diffusion coefficient, , defines the rotational Peclet number (Pe = y/ ). When the rotational Peclet number is small (i.e., near zero), the anisotropic particles are randomly oriented by diffusion. When the rotational Peclet number is large, the particles rotate but have a preferential orientation aligned with the shear. The period of rotation is given by... 

In Ref. [257], Sii- Cx alloy films with x< 0.1 were deposited on Si by molecular beam epitaxy (MBE) to use them for the substrates of heteroepitaxial diamond films. It was expected that when x = 4.33%, a perfect lattice match of Sii C c D = 2 3 occurs and the degree of orientational alignment could be improved. An EIOD film, grown to a thickness of 20 pm using the BEN process, successfully resulted in a (100)-oriented film with (100) faces at the film surface, but the FWHM of the (111) XPF was 6°, the same value as when the direct nucleation of diamond was done on Si using BEN. The results of Raman spectroscopy and XRD of the diamond films were not dependent on the x value. It was thus confirmed that the orientational characteristics of the HOD films had no significant dependence on the C content of the Sii C,v layers. This work can be compared with that of Ref. [258], where layers with x= 1.4 and 3.5% were deposited on Si(lOO) by... 

Fig. 5 (a) Electrospinning setup using an auxiliary counter electrode to direction the path of an electrospinning jet. (b, c) A tubular structure with diagonally oriented aligned nanofibers was fabricated when a mandrel was placed in the path of the jet at an angle [87]... 

In order to understand the overall orientation of the chromophores within guest-host systems under differing external electric fields, we examine the orientational alignment of the dipole moment of the chromophores with respect to the direction of the external electric field. In the non-interacting rigid gas model, the intermolecular electrostatic interactions are ignored and one can describe a general order parameter of... 

First, all molecules or particles rotate in a shear flow, but if they are not precisely spherical, the flow causes an orientation aligned in the direction of the flow to last for a longer time than orientation perpendicular to the flow (Section 5.1.1). This implies that average flow disturbance, and thereby viscosity, is smaller. The alignment depends on the rate of rotary diffusion of the particles in relation to the magnitude of the shear rate. The rotary... 

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