Ladder characterization

The so-called ladder equivalent circuit shown in Figure 27.13 is characteristic of many ACs. It represents a set of several R-C parallel circuits and also Warburg diffusion impedance. Herewith, apart from the proper distributed line related to a porous structure of the studied object, one or several circuits in the ladder characterize parallel faradaic redox reactions of surface groups on the electrode. It was shown theoretically that phase angle (p = 45° independent of frequency co is observed... 

This compound has been investigated by several groups,379- 384 but due to its practical insolubility it has not been fully characterized. Another approach to obtain phthalocyanine network polymers is with the use of crown ethers385 or other groups like di oxy -para-p h enyle n e3 8 6 as bridging units between the macrocycles. Some attempts to obtain metal phthalocyanine substructures arranged as ladder polymers have also been proposed (see below).344... 

This SRM contains human cells from two cell culture lines from which DNA can be extracted, genomic DNA from those two cell lines plus eight individuals, PCR-amplified DNA from the two cell lines plus four of the eight individuals, a D1S80 allelic ladder for characterization of amplified DNA, and a DNA size marker to assure proper electrophoretic separations. 

The structure of coordination polymers formed with 3,6-bis(pyridin-3-yl)-l,2,4,5-tetrazine and zinc salts can be controlled by the choice of alcoholic solvents. Infinite lattice compounds of the form [Zn2L2(N03)4(Me0H)2(//-L)] and [Zn2(/U-L)3(N03)4](CH2C12)2) have been structurally characterized. The former structure shows an alternating single- and double-bridged species whereas the latter exists as a non-interpenetrated ladder complex.273... 

Very often, however, these dyads are not isolated in the solid state and interact with neighboring ones at least along one preferential direction. In this case, we can distinguish two important situations the alternated spin chain and the spin ladder. As shown in Scheme 5, the alternated spin chain is characterized with two different magnetic interactions, noted / and aJ with 0 < a < 1. Note that if a = 0, one recovers the singlet-triplet behavior while if a = 1, we are in the presence of a uniform spin chain. The spin ladder is also characterized by two J values, noted J// and J in the following. 

More recently this same phosphide has been structurally characterized as the LiCl adduct, [(THF)LiCl (THF)2Li(PBu2)]2 (34). Again the structure takes the form of a four-rung ladder however, the central two rungs are now part of a Li2Cl2 cycle and the two terminal Li atoms are each coordinated by two molecules of THF. The ladder motif is broken down by the addition of the bidentate ligand DME The recently reported complex [Li(PBu2)(DME)]2 (DME = 1,2-dimethoxy-... 

Schrodinger s equation has solutions characterized by three quantum numbers only, whereas electron spin appears naturally as a solution of Dirac s relativistic equation. As a consequence it is often stated that spin is a relativistic effect. However, the fact that half-integral angular momentum states, predicted by the ladder-operator method, are compatible with non-relativistic systems, refutes this conclusion. The non-appearance of electron... 

S. Setayesh, D. Marsitzky, and K. Mullen, Bridging the gap between polyfluorene and ladder-poly-p-phenylene synthesis and characterization of poly-2,8-indenofluorene, Macromolecules, 33 2016-2020, 2000. 

Infrared spectroscopy is of limited value in the characterization of thi-anthrenes (71MI1), though a comparison of intensities for peaks at 875 and 805 cm , for the out-of-plane bendings corresponding to isolated and adjacent hydrogens, respectively, was used to estimate the ratio of ladder-polymer 12 and polymer 13 in a mixture (85MI2 88MI3). 

For many polymers, the structural identity of all the constitutional repeating units and of their sequential arrangement is not known, yet some indication is available as to their general characterization such as ladder or spiro polymers. 

The complex forms purple air-stable crystals and has good solubility in both polar and nonpolar solvents (e.g., acetone, dichloromethane, tetrahydro-furan, benzene, and hexane). It has been characterized crystallographically.7 The structure is an open, but folded, ladder-like array of six metal atoms with the two platinum atoms in the center. The IR spectrum (hexane) exhibits V(co> bands at 2085 (m), 2062 (vs), 2035 (vs), 2016 (w). Pt2Ru4(CO)18 has been found to be very useful for the synthesis of new platinum-ruthenium cluster complexes.10,12,13... 

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