From a discretization of the path integral formulation of quantum mechanics, it is possible to relate equilibrium quantum many body theory to classical statistical mechanics. In this paper, we significantly extend and analyze this well known isomorphism in terms of the equilibrium theory of classical molecular fluids composed of flexible polyatomic species. We show how quantum influence functionals are isomorphic to classical cavity distribution functions. The former describe the influence of surrounding media on the dynamics of quantal degrees of freedom, and the latter describe environmental effects for classical models of flexible molecules and chemical equilibria. The connection allows the use of classical theories to perform nonperturbative calculations of influence functionals which treat the influence functionals and many body correlation functions in a self‐consistent fashion. We illustrate the computational advantages of the method by studying its predictions for a hard sphere model of liquid helium above the l transition. The nature of quantum indistinguishability of identical particles (i.e., quantum exchange) is treated in our theory in terms of an exact isomorphism with chemical equilibria. This connection allows the treatment of exchange in condensed phases in terms of the classical law of mass action, and provides a computational advance over existing methods for interacting systems. By picturing exchange in terms of classical association equilibrium, we arrive at a view (hinted at long ago by Feynman and by Penrose and Onsager) in which the Bose condensation is related to an equilibrium polymeric sol–gel transition. Thus, below the l transition, the correlations in liquid helium are equivalent to those in a classical fluid containing a finite concentration of macroscopic polymers. We stress how the path integral aspect of the isomorphism leads to useful geometrical interpretations of quantum phenomena. For example, tunneling phenomena can be viewed in terms of solitonic (or instantonic) configurations or flexible chain molecules. With this picture, we show how the isomorphism can be employed to understand both adiabatic and nonadiabatic solvent effects on chemical bonding. For concreteness, we provide a detailed analysis of a particular model of the chemical bond for which a partial summation over intermediate quantum paths leads to an Ising model problem in the isomorphism. While applications like this are presented in the form of qualitative illustrations, a variety of methods can be employed to produce quantitative results. We sketch how these calculations can be performed for various problems, making connections with methods like the renormalization group (RG) technique. The classical isomorphism together with the modern theory of classical polyatomic systems provides a powerful framework for quantitative solutions of condensed matter quantum mechanical problems.

Exploiting the isomorphism between quantum theory and classical statistical mechanics of polyatomic fluids

Ordered anion adlayers on metal electrode surfaces.

Application of electrolyzed water in the food industry

A review is presented dealing with the use of carbon paste as an electrode maaterial for electrochemical sensors (311 references). It covers mainly publications which appeared during the period 1990–1993; numerous applications demonstrate the widespread applicability of carbon paste in the field of electrochemical analysis, such as voltammetry, amperometry, and potentiometry, but also as an electrode for electrochemical detectors in flow systems.

Sensors based on carbon paste in electrochemical analysis: A review with particular emphasis on the period 1990–1993

Un pretraitement electrochimique nettoie l'electrode de ses contaminants introduit au cours du polissage et entraine une oxydation superficielle qui influence certaines reactions

Characterization of electrochemically pretreated glassy carbon electrodes

The chlorine loss of electrolyzed oxidizing (EO) water was examined during storage under different light, agitation, and packaging conditions. The chlorine loss of pH-adjusted EO water was also examined. Under open conditions, the chlorine loss through evaporation followed first-order kinetics. The rate of chlorine loss was increased about 5-fold with agitation, but it was not significantly affected by diffused light. Under closed conditions, the chlorine loss did not follow first-order kinetics, because the primary mechanism of chlorine loss may be self-decomposition of chlorine species rather than chlorine evaporation. The effect of diffused light was more significant compared to agitation after two months of storage under closed conditions. The chlorine loss of EO water and commercial chlorinated water decreased dramatically with the increase of pH from the acidic (pH 2.5) to the alkaline (pH 9.0) region.

Effects of storage conditions and pH on chlorine loss in electrolyzed oxidizing (EO) water.

The optimum composition of a compression-molded Kel-F-graphite composite electrode is investigated for the electrochemical (EC) detection of effluents, including phenollic compounds, separated by reversed-phase high-performance liquid chromatography (HPLC). Optimum compositions of 10 to 15% graphite by weight can be rationalized on the basis of the particulate structure of the graphite active sites. The electrode is compatible with a wide range of organic solvents and its linear response to the target compounds extends over 5 orders of magnitude in concentration. The detector has been applied for the determination of a range of phenolic species in natural water and a coal gasifier waste water sample. Detection limits for a variety of phenols range from 3 to 15 pg. Repetitive injections yield peak heights with RSDs typically less than 1%. The long-term stability of the electrode is also demonstrated.

Kel-F-graphite composite electrode as an electrochemical detector for liquid chromatography and application to phenolic compounds

Fabrication and characterization of a Kel-F-graphite composition electrode for general voltammetric applications

Proprietes et avantages des microelectrodes de graphite comme detecteurs par rapport aux electrodes solides

Microarray electrochemical flow detectors at high applied potentials and liquid chromatography with electrochemical detection of carbamate pesticides in river water

Vieillisement rapide en quelques heures, mais ensuite bonne stabilite au moins sur 24 heures

James L. Anderson

Papers

Effects of storage conditions and pH on chlorine loss in electrolyzed oxidizing (EO) water.

Kel-F-graphite composite electrode as an electrochemical detector for liquid chromatography and application to phenolic compounds

Fabrication and characterization of a Kel-F-graphite composition electrode for general voltammetric applications

Microarray electrochemical flow detectors at high applied potentials and liquid chromatography with electrochemical detection of carbamate pesticides in river water

Amperometric response of microlithographically fabricated microelectrode array flow sensors in a thin-layer channel