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SERS technique wae used to study the chemiesorption kinetics of Methylene Blue (MB) on the HNO3-etched silver surface. The adsorption kinetic parameters were deduced from different vibrational modes at a low concentration of 3.5 × 10−6 mol/L, and it showed that MB adsorbed uniformly (monolayerly) on silver surface. However, the adsorptive behavior turned anomalous at relatively higher concentrations and a possible explanation was suggested. In addition, the influence of Cl− ions on the adsorption states of MB was investigated, and it was shown that MB molecules, adsorbed on the silver surface, tended to transform the “lying-down” state to the “end - on” 4 state after CI− ions were added.

SERS has been used as a state-resolving probe to study the adsorption states. in the case of pyridine (Py) adsorbed on the Ag electrode surface, the equilibrium and transition between two adsorbed states, i.e., the perpendicular mode adsorbed through the nitrogen lone-pair electrons and the flat mode through the π electrons of the aromatic ring, were studied. It was found that in the low pyridine concentration or the initial stage of adsorption, the flat mode was favored. While the concentration became higher and the adsorption tended to equilibrium, the adsorbed molecules would transit to the perpendicular mode. The similar phenomenon was also observed when changing the applied electric potential and the pH value of the solution. In the case of the adsorption of Methylene Blue (MB) on the HNO3-etched silver surface, the influence of Cl− ions on the adsorption states of MB was investigated. It showed that MB molecules adsorbed on the silver surface tended to transform from the “lying-down” state ...

The fullerenated PEPC (Poly(epoxy propyl carbazole)) was synthesized in Friedel-Crafts type reactions. Molecular weights of the polymers were determined by gel permeation chromatography. Structures of the polymers were analyzed and characterized by use of 'H and 13 C NMR, FT-IR, thermal analysis and spectroscopic methods. The 13 C NMR spectrum of fullerenated PEPC exhibits structured peaks in the fullerene region. Compared with pure PEPC, fullerenated PEPC has the same structure in UV region of the absorption spectrum and extends the active range to longer wavelength. The apparent quenching of PEPC fluorescence was observed in the fullerenated polymer and it can be attributed to intramolecular excited state energy transfer. The fullerenated PEPC is soluble in common organic solvents such as THF and chloroform. The process can be generalized to other polymers having phenyl groups to produce a series of fullerenated polymers.

Using a concept called subgeneral position and adapting a weight function created by E. I. Nochka, this work proves the Cartan's conjecture on defect relations for a degenerate meromorphic map from a parabolic manifold into a projective space. In value distribution theory, defect relations for a nondegenerate meromorphic map are well known. When the map is degenerate, the situation is not so good. A defect relation was conjectured by H. Cartan [1] in 1933. It remained unproved until 1982 when Nochka [4] was published. Nochka [4] deals with only a degenerate meromorphic curve; i.e., the domain of the map has dimension one. When the domain has dimension greater than one, no defect relations for degenerate meromorphic maps have been known. After a discussion of the Second Main Theorem, this work has succeeded in establishing a Nevanlinna defect relation for a meromorphic map (degenerate or nondegenerate) from a parabolicmanifold into a projective space. The defect relation is rather general. It contains as special cases all the known Nevanlinna defect relations for such kind of meromorphic maps. The basic idea of this work is very simple: transform the problem with a degenerate meromorphic map into the one with a nondegenerate meromorphic map. The difficulty is, after such a transformation, the originally given hyperplanes in general position become hyperplanes not in general position. We overcome this obstacle by introducing a concept called subgeneral position (see Chen [2, 3]). The defect relation comes from the Second Main Theorem, while the latter depends on two inequalities: the Product to Sum Estimate and the Ahlfors Estimate. Degeneracy of a map does not affect the Ahlfors Estimate, but it does affect the Product to Sum Estimate. To build a desired Product to Sum Estimate, we adapt a weight function created by Nochka [4] and proved in Nochka [5]. To save pages and to make basic ideas clearer, we take two steps: first, we prove only a result for hyperplane targets, the defect relations for associated Received by the editors September 21, 1987. 1980 Mathematics Subject Classification (1985 Revision). Primary 32A22, 32H30.