Field Evaluation of N-Methyl-4-hydrazino-7-nitrobenzofurazan (MNBDH) Coated Silica Gel Cartridges for the Measurement of Lower Carbonyls in Air

A rapid analytical method based on Soxhlet extraction has been developed for determination of polycyclic aromatic hydrocarbons (PAH) in palm dates and tuna fish. The method is based on selected ion-storage gas chromatography–mass spectrometry. In the work discussed we were interested in the analysis of 16 polycyclic aromatic hydrocarbons (PAH) regarded by the EPA as priority pollutants. Soxhlet extraction of real, fortified, and blank samples, with hexane as solvent, was used to extract the analytes of interest. An excellent detection limit and good relative standard deviations (RSD) were obtained and analysis time was short. The linearity and sensitivity of the method for measurement of these analytes at trace levels are discussed.     

Probing 1D super-strongly correlated dipolar quantum gases

One-dimensional (1D) dipolar quantum gases are characterized by a very special condition where super-strong correlations occur to significantly affect the static and dynamical low-energy behavior. This behavior is accurately described by the Luttinger Liquid theory with parameter K < 1. Dipolar Bose gases are routinely studied in laboratory with Chromium atoms. On the other hand, 1D realizations with molecular quantum gases can be at reach of current experimental expertises, allowing to explore such extreme quantum degenerate conditions which are the bottom line for designing technological devices. Aim of the present contribution is to focus on the possible probes expected to signal the reach of Luttinger-Liquid behavior in 1D dipolar gases.     

Determination of low boiling aldehydes in air and exhaust gases by using annular denuders combined with HPLC techniques

Summary An improved procedure for the HPLC determination of C₁–C₃ aldehydes in environmental samples is described. These air pollutants are quantitatively collected on annular denuders coated with 2,4-Dinitrophenylhydrazine and analyzed as hydrazone derivatives by HPLC with UV absorbance and voltammetric detection. Collection efficiencies of aldehydes are reported and compared with other available methods. Practical examples of the application of the method are given.This work has been part of the Dottorato di Ricerca program carried out at the University of Rome.Dedicated to Prof. Dr. A. Liberti on the occasion of his 70th birthday.     

HARVESTING ECONOMIC MODELS AND CATCH‐TO‐BIOMASS DEPENDENCE: THE CASE OF SMALL PELAGIC FISH

Abstract In the case of small pelagic fish, it seems reasonable to consider harvest functions depending nonlinearly on fishing effort and fish stock. Indeed, empirical evidence about these fish species suggests that marginal catch does not necessarily react in a linear way neither to changes in fishing effort nor in fish stock levels. This is in contradiction with traditional fishery economic models where catch‐to‐input marginal productivities are normally assumed to be constant. While allowing for nonlinearities in both catch‐to‐effort and catch‐to‐stock parameters, this paper extends the traditional single‐stock harvesting economic model by focusing on the dependence of the stationary solutions upon the nonlinear catch‐to‐stock parameter. Thus, we analyze equilibrium responses to changes in this parameter, which in turn may be triggered either by climatic or technological change. Given the focus in this study on the case of small pelagic fish, the analysis considers positive but small values for the catch‐to‐stock parameter.