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F Mangani

Publications and source records attributed to F Mangani.

51 records · Page 3Linked to original sources
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New trends in the application of electron ionization to liquid chromatography-mass spectrometry interfacing.

I. Introduction 88 II. Cap-EI Interface 90 A. Interface Performance 92 III. Direct-EI Interface 93 A. Interface Performance 97 IV. Conclusions 103 Acknowledgments 103 References 103 --Two recent approaches for coupling capillary scale liquid chromatography and electron ionization mass spectrometry are reviewed and discussed. The first one, Cap-EI, is the latest evolution of the micro-scale particle beam interface, in which the nebulizer has been optimized to overcome the limitations of the former approach, in terms of sensitivity and linearity. It can be easily hosted in pre-existing instruments without major modifications and can use helium and the less-expensive nitrogen to generate library-matchable electron ionization spectra. The second one is a miniaturized interface for nano- and micro-HPLC, in which the interfacing process takes place into a suitably modified ion source. Because the eluate from the column is completely transferred into the ion source for ionization, superior sensitivity, linearity, and reproducibility are obtained. No signs of chemical ionization are observed at flow rates up to 1.5 microL/min. These two interfaces demonstrate that electron ionization can be successfully used for the analysis of small-medium molecules of various polarities, and also at the trace level. The possibility to record library-matchable electron ionization spectra offers the analyst a powerful tool that can be particularly useful in real-world applications.

Caffeine↗
PubMedDate not supplied

[Evaluation to the exposure to polycyclic aromatic hydrocarbons, benzene, toluene and xylenes in workers in a power plant fueled with heavy oil].

Occupational exposure to polycyclic aromatic hydrocarbons (PAHs) has been demonstrated in many industrial sectors. However, up to date there are few studies in the literature on PAH exposure in thermoelectric power plants. The study was aimed at the evaluation of personal exposure to PAHs in workers of a power plant fueled with heavy oil. Exposure to polycyclic aromatic hydrocarbons (PAHs) and to benzene, toluene and xylenes (BTX) was evaluated on power plant workers exposed to heavy fuel oil; the control group consisted of office workers of the same power plant. Altogether 39 subjects were studied, for a total of 84 days of monitoring. Personal environmental exposure, cutaneous exposure and urinary concentrations of 1-hydroxypyrene (1-OHP), trans,trans-muconic acid (TTMA) and nicotine were measured. Personal environmental exposure to PAHs was very low; only maintenance workers showed exposure to total carcinogenic PAHs significantly higher than controls (median levels 3.05 and 0.88 ng/m3 respectively). All workers showed very low levels of dermal exposure to PAHs (less than 1 ng). The median 1-OHP urinary concentrations were 0.16, 0.11 and 0.08 mumol/mol creatinine in the groups of exposed workers and 0.08 mumol/mol creatinine in the control group. Neither the exposed workers nor the controls showed a significant increase in 1-OHP urinary concentrations across the shift. The regression analysis showed a significant effect of cigarette smoking on urinary 1-OHP, while no association was observed between occupational exposure and diet. Personal environmental exposure levels to BTX were very low. TTMA urinary concentrations of the exposed subjects were similar to those of the controls. No significant increase in the TTMA urinary concentrations was observed across the shift and, as expected, smokers showed higher values than non-smokers. The study did not show a measurable intake of PAHs and BTX in power plant workers that could be ascribed to occupational exposure, thus confirming the efficacy of the protective measures in force.

Benzene↗
PubMedDate not supplied

The wall paintings in the Oratorio of San Giovanni Battista in Urbino: a study finalized to a correct conservation project.

The walls of the Oratorio of San Giovanni Battista in Urbino are decorated with outstanding mural paintings dating back to the 15th century. Due to degradation processes that have occurred in the past years, such paintings require a conservative restoration project. In order to evaluate reasons of the decay, some scientific studies have been performed. They consist of macroscopic observations and chemical (EDS), morphological (SEM) and mineralogical (XRD) analyses of samples both from the original preparatory layers under the painted layers and from the restored plasters at the surbase of the wall. In addition, environmental studies have been performed to verify microclimatic conditions of the church in which the mural paintings are located. Finally, a conservative restoration project was proposed.

Architecture↗
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[Non-bioavailability of carcinogenic polycyclic aromatic hydrocarbons contained in coal dust].

The aim of the study was to ascertain whether polycyclic aromatic hydrocarbons (PAHs) especially 3,4-benzo(a)pyrene, could be eluted from coal dust that comes into contact with biological fluids or crosses the skin barrier. A fine-grained coal dust with known PAH content was placed into contact with homogenized pig lung or human gastric juices, and also applied to monkey skin, using the cutaneous window method. The results demonstrate that, in the in vitro systems used, PAHs contained in coal dust are not eluted by lung homogenate or gastric juices, nor are they capable of crossing the skin barrier. These results justify and support the interpretation given to the results of experimental carcinogenicity studies on coal dust which never succeeded in demonstrating a higher incidence of cancer, particularly lung cancer, in treated animals.

Animals↗