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In recent years a new kind of threat, known as Hardware Trojan, is affecting the Integrated Circuit industry. Un-trusted parties in the supply chain may take advantage of the segmentation in the production to inject malicious hardware components that became active under specific circumstances. As it is impractical to identify such malicious hardware with in-lab testing, most countermeasures are based on hardware alterations, with the drawback of increasing production costs, area, and energy consumption of the final product. In this paper, on the contrary, we propose a software-based, cost-effective solution that minimizes the chance of activation of a multi-stage trigger Hardware Trojan. The approach relies on a pure-software obfuscation mechanism, which exploits an evolutionary algorithm to modify an executable program without affecting its functionalities. Such obfuscation can be used to protect critical infrastructures and operations with a reduced and predictable loss of performances. The proposed technique has been evaluated against a well-known real-world hardware attack, getting positive and promising results concerning its effectiveness.

The chemical characterization of the bark from eight broad-leaved trees ( Betula pendula, Quercus suber, Quercus ilex, Castanea sativa, Quercus robur, Carpinus betulus, Fagus sylvatica and Populus nigra ) was carried out using evolved gas analysis-mass spectrometry (EGA-MS) and gas chromatography/mass spectrometry (GC/MS) following alkaline hydrolysis, solvent extraction and derivatisation with a sylilating agent. Not only does bark account for a high percentage of residues from forestry and the wood industry, but it is also rich in suberin, a biopolyester, whose sub-monomeric units can be converted into value added chemicals, as well as being used as starting blocks for the production of new materials. EGA-MS along with principal component analysis (PCA) of the mass spectral data were used to obtain information on the thermal complexity of the barks and on the thermal degradation areas of all their main chemical constituents: suberin, polysaccharides, lignin, tannins and extractives. GC/MS analysis was used for the depolymerisation of suberin, and to examine its monomeric composition. This enabled us to determine aliphatic and mid-chain substituted long-chain α,ω-diacids and ω-hydroxyacids (all with mainly 16, 18, and 22 carbon atoms) along with aliphatic long-chain alkanoic acids and alkanols. Our results may be useful for the exploiting the investigated barks – but not just for energy recovery. In fact, as their suberin shows a high abundance of mid-chain substituted monomers, alternative uses are possible such as the synthesis of polymeric materials by condensation and cross-linking reactions.

Within an integrated management plan for contaminated site remediation at a given territorial scale, the performance of treatability tests could be useful and/or expressly requested by the control authority on a site-specific basis to evaluate the overall feasibility of a given remedial option. The thermal desorption process appears to be a favorable treatment technology for organic contaminants. In this context, a particular lab-scale, indirectly heated desorber for treatability tests was originally developed and first applied to natural soils with different textures (silty sand, loam, silt clay, and clayey silt) that were “ad hoc” highly contaminated with diesel oil at various desorption process conditions (heating temperature in the range of 300–390°C, and reactor retention time in the range of 40–120 min). The Italian soil threshold level for heavy hydrocarbons (C > 12) of 50 mg kg−1 (dry matter) was assumed to be the successful goal of the treatability studies. In addition to the individuation of the...

Using the renowned shoe manufacturing sector in Marche Region (Italy) as a case-study, this paper deals with the characterisation of (1) the chemical and physical properties of representative types of shoe manufacturing wastes, (2) the quality profile of a particular material recovery finalised to a soil destination, and (3) the flue gas emissions from burning tests in view of the potential for energy recovery. The property characterisation has primarily revealed the following aspects: a general condition of resulting higher ash contents in shoe waste materials having a mineral or synthetic processing origin; and relatively high energy contents, ranging on the whole expressed as LHV (lower heating value) from 15,710 kJ kg−1 (for vegetable-tanned leather dust) to 42,439 kJ kg−1 (for natural rubber). The characterisation of a fertiliser that can be generated from the particular waste type of vegetable-tanned leather dust has determined an interesting quality profile classifiable as organic-nitrogen fertiliser with acceptable values of the humification parameters and heavy metal contents significantly below the assumed quality limits. Finally, simplified pilot-scale burning tests have provided the following findings: higher NOx emissions produced from leather-based materials as compared with the cellulose-based material, which are likely attributable to the substantial “fuel nitrogen” content of the original animal skins; higher HCl emissions produced from the leather-based materials in comparison with the cellulose-based material; and a more even combustion process occurred for the leather dust than for the other shoe materials.

Referring to the industrial wood waste category (as dominant in the provincial district of Pesaro-Urbino, Marche Region, Italy), this paper deals with the experimental characterisation and the carrying out of non-controlled burning tests (at lab- and pilot-scale) for selected 'raw' and primarily 'engineered' ('composite') wood wastes. The property characterisation has primarily revealed the following aspects: potential influence on moisture content of local weather conditions at outdoor wood waste storage sites; generally, higher ash contents in 'engineered' wood wastes as compared with 'raw' wood wastes; and relatively high energy content values of 'engineered' wood wastes (ranging on the whole from 3675 to 5105 kcal kg{sup -1} for HHV, and from 3304 to 4634 kcal kg{sup -1} for LHV). The smoke qualitative analysis of non-controlled lab-scale burning tests has primarily revealed: the presence of specific organic compounds indicative of incomplete wood combustion; the presence exclusively in 'engineered' wood burning tests of pyrroles and amines, as well as the additional presence (as compared with 'raw' wood burning) of further phenolic and containing nitrogen compounds; and the potential environmental impact of incomplete industrial wood burning on the photochemical smog phenomenon. Finally, non-controlled pilot-scale burning tests have primarily given the following findings: emission presence ofmore » carbon monoxide indicative of incomplete wood combustion; higher nitrogen oxide emission values detected in 'engineered' wood burning tests as compared with 'raw' wood burning test; and considerable generation of the respirable PM{sub 1} fraction during incomplete industrial wood burning.« less

Because home composting is a prevention option in managing biowaste at local levels, the objective of the present study was to contribute to the knowledge of the process evolution and compost quality that can be expected and obtained, respectively, in this decentralized option. In this study, organized as the research portion of a provincial project on home composting in the territory of Pesaro-Urbino (Central Italy), four experimental composters were first initiated and temporally monitored. Second, two small sub-sets of selected provincial composters (directly operated by households involved in the project) underwent quality control on their compost products at two different temporal steps. The monitored experimental composters showed overall decreasing profiles versus composting time for moisture, organic carbon, and C/N, as well as overall increasing profiles for electrical conductivity and total nitrogen, which represented qualitative indications of progress in the process. Comparative evaluations of the monitored experimental composters also suggested some interactions in home composting, i.e., high C/N ratios limiting organic matter decomposition rates and final humification levels; high moisture contents restricting the internal temperature regime; nearly horizontal phosphorus and potassium evolutions contributing to limit the rates of increase in electrical conductivity; and prolonged biowaste additions contributing to limit the rate of decrease in moisture. The measures of parametric data variability in the two sub-sets of controlled provincial composters showed decreased variability in moisture, organic carbon, and C/N from the seventh to fifteenth month of home composting, as well as increased variability in electrical conductivity, total nitrogen, and humification rate, which could be considered compatible with the respective nature of decreasing and increasing parameters during composting. The modeled parametric kinetics in the monitored experimental composters, along with the evaluation of the parametric central tendencies in the sub-sets of controlled provincial composters, all indicate that 12-15 months is a suitable duration for the appropriate development of home composting in final and simultaneous compliance with typical reference limits.

Landfill gas is a product of the natural biological decomposition of organic material contained in wastes deposited in landfills. This denomination generically indicates a gas mixture made of methane and carbon dioxide. These gases are produced until most of the organic material in the waste has been degraded. Emissions from municipal landfill sites are therefore potentially harmful to both local and global air quality; the global emissions of an important greenhouse gas such as methane are estimated to be between 20 and 70 Tg year−1. Moreover, landfills have been shown to be a major source of anthropogenic halogenated greenhouse gases such as chlorofluorocarbons (CFCs) and their hydrogenated substitutes (HCFCs, HFCs). These long-living gases are emitted into the atmosphere as a consequence of leakage occurring in landfills where chlorine containing equipment and materials have been dumped. In this study, municipal landfills of different ages located in Tuscany (central Italy) have been investiga...

We describe a method, based on a new nano-HPLC gradient generator coupled to a modified direct electron ionization (EI) LC–MS interface, for the analysis of several compounds of environmental interest. The gradient generator was installed on a conventional HPLC system and the nano-flow rate was achieved using a double splitter. Reproducible gradients of different shapes (i.e. linear, convex, concave) can be generated at micro- and nano-flow rates. This attribute makes this device particularly appropriate for coupling with direct-EI LC–MS interface. The combination of the gradient generator with the direct-EI interface optimizes the analytical conditions for the generation of good quality EI spectra for trace level analytes. The performance of this new system was tested at a flow rate of 250 nl min−1, evaluating linearity, intra-day reproducibility and limits of detection of several compounds of environmental interest belonging to three different classes: nitro-polycyclic aromatic hydrocarbons, pesticides and human hormones. Excellent signal stability and low detection limits were obtained in most cases. Enhanced performance was observed for critical separations due to the possibility to run gradients of different shapes.

Carbograph 6, a new graphitized carbon black with a specific surface area of 203 m2 g−1, as measured by BET, both uncoated and coated with up to 12% (w/w) of squalane, a non-polar stationary phase, has been studied by gas chromatographic determination of the enthalpy, entropy, and free energy of adsorption of a series of alkanes (C2−C6) and benzene. The data obtained are discussed and compared with those available in the literature for other graphitized carbon blacks. An example of a separation obtaned with Carbograph 6 is reported.

Water-soluble organic compounds (WSOC) often represent a large fraction of the total organic mass found in the atmospheric aerosol. They play a very important role in determining the ability of aerosol particles to act as cloud condensation nuclei (CCN), influencing cloud and fog formation and cloud albedo. Molecular characterization of WSOC in fogwater samples was achieved using a two-stage ion-trap mass spectrometer equipped with electrospray ionization (ESIMS/MS). Negative ionization conditions in the electrospray interface finalized our characterization of the acidic fraction of WSOC that comprises both mono- and di-carboxylic acids and polycarboxylic acids for which a similarity was suggested with naturally occurring humic (or fulvic) acids, and which are sometimes referred to in the literature as humic-like substances (HULIS). Molecular structure elucidation was accomplished using several model compounds and exploiting mass spectral resolution for compound separation. Single compound identification ...

The volatile fraction of heavy fuel oils used in thermal power plants is characterized by the presence of trace amounts of potentially carcinogenic compounds, i.e. benzene and toluene, ethylbenzene and the xylenes (BTEX). In this paper, an original methodology for the determination of these compounds in such a complex matrix is presented. It consists of a capillary gas chromatographic-quadrupole mass spectrometric method preceded by the extraction and enrichment of the substituted benzenes by using a “purge and trap” technique. Results obtained analyzing heavy fuel oil actual samples are reported as well.

Chlorofluorocarbons are man-made long lasting atmospheric pollutants of great environmental concern, responsible for important global change phenomena. Recently, they were replaced by hydrogenated halocarbons that, even if less persistent, do not lack in environmental impact. Atmospheric concentrations of these compounds were measured in Antarctica by gas chromatography. The extremely low atmospheric mixing ratios of these compounds require a pre-concentration step of the air sample on suitable adsorbent in order to meet the sensitivity of the analytical method Results obtained analyzing air samples collected in Antarctica since 1988 for the determination of CFC-12 and CFC-11 are reported, together with data concerning the less abundant species.

Permission to reproduce this table online was not granted by the copyright holder. Readers are kindly asked to refer to the printed version. 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 μL/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.© 2001 John Wiley & Sons, Inc., Mass Spec Rev 20: 88–104, 2001

Human erythrocytes were loaded with myo-( 3 H)-inositol in the presence or absence of cytidine trisphosphate to investigate the synthesis of membrane phosphoinositides in the intact red cell. The addition of cytidylic nucleotides to the loading mixture yielded a four-fold increase in the ( 3 H)-labeling of the membranes. The ( 3 H)-labeling of phosphatidylinositol, phosphati- dylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate was distinguished by two chromatographic techniques. Experi- ments performed on white ghosts demonstrated the presence of CDP-diacylglycerol synthase and phosphatidylinositol synthase. These results and those already reported allow to discuss a possible turnover of the inositol polar head. © Societe francaise de biochimie et biologie moleculaire/Editions scientifiques et medicales Elsevier SAS phosphoinositides / erythrocyte / myo-inositol / loading / membrane

CCl3F (or CFC-11) and CCl2F2 (or CFC-12) were determined in air samples collected, during subsequent summer Antarctic campaigns, in different sampling sites in the Ross Sea Region. The samples were analysed by GC-ECD after enrichment. Data obtained since 1988–89 were plotted to observe the trend of CFCs atmospheric concentration levels. A decrease in the rate of increase of CFC-12 concentration was observed, whilst the concentration of CFC-11 was actually seen to be decreasing.

A method for the characterization of coal thermal behaviour, based on gas chromatographic-mass spectrometric analysis of the pyrolysate, is presented. Twelve different coal samples, representative of the entire coal rank, were selected for this study. The pyrolysis products, obtained at 800°C, were first collected and then analysed in two GC-MS systems. The sampling apparatus consisted of three different traps in order to separate the products into three fractions on the basis of their volatility. The GC-MS analysis was also arranged according to this criterion. A packed column, coupled to a double-focusing magnetic mass spectrometer, was used for the volatile fractions of the pyrolysate and a capillary column, coupled to a quadrupole analyser, was employed for the analysis of the condensed fraction. Sampling and analysis procedures were carried out separately, thus allowing careful optimization of the strategy for the characterization of the pyrolysate. The condensate was analysed in the selected-ion monitoring mode for the determination of different classes of compounds. Some evaluations and comparisons, extrapolated from the results obtained, are presented.

Geochemical investigation of gas emissions at low temperatures in areas of Quaternary volcanism shows a systematic enrichment of aromatic hydrocarbons and alkenes in fumaroles from active volcanic areas (Vulcano and Phlegrean Fields, Italy; S. Miguel, Terceira and Graciosa, Azores; Chichon, Mexico; Uzon and Geyser Valley, Kamchatka) and geothermal systems (Larderello area, Italy) with respect to those pertaining to areas of recent but exhausted volcanism (Vulsini and Sabatini volcanic districts, Torre Alfina volcano, Italy). The general behaviour of hydrocarbons in the investigated gas-emissions, together with thermodynamic and experimental data (taken from the industrial treatment of petroleum) suggest possible abiogenic processes acting on degradation of alkane hydrocarbons when source temperatures exceed 150° and acid species together with high active-surface area clay minerals are available. Benzene shows very similar enrichments in emissions from Vulcano beach and Phlegrean Fields, Kamchatka and Azores, pointing out the possible occurrence of catalytic reactions at the source. Alkenes display significant relative increases in crater fumaroles from Chichon volcano. Moreover, lower carbon-number alkenes (propene and ethene) progressively appear with increasing alkenes/alkanes ratio, suggesting an increasing importance of thermal-cracking reactions. The general similarities in distribution patterns from different active volcanic environments allow us to reappraise the influence of the nature of sources and to emphasize the effects of abiogenic reactions. With reference to areas of active volcanism, the distribution of hydrocarbons can represent a useful parameter to evaluate the prevailing physico-chemical conditions and their time-space variabilities. Accordingly they can give a significant contribution to the geochemical monitoring of active volcanic areas.

Volcanic gas emissions are strictly related to a specific stage of volcanic activity. Complete knowledge of their chemical composition can be extremely useful for efficient geochemical surveillance of active volcanism sites. A new, effective and simple method for the evaluation of light hydrocarbons in volcanic gases is described. A rapid sampling procedure and GC-FID analysis are employed. Data from different volcanic areas are shown and a their possible correlation is also discussed.

Referring to the industrial wood waste category (as relevant in the provincial furniture district of Pesaro-Urbino, Italy), this paper deals with the experimental characterization and the carrying out of lab-scale non-controlled burning tests for selected “raw” and primarily “engineered” wood residuals. The property characterization has primarily revealed the following aspects: potential influence on moisture content of local weather conditions at outdoor wood residual storage sites; generally, higher ash contents in “engineered” wood residuals as compared with “raw” wood residuals; higher energy content values in fiber-wood as compared with particle-wood typologies. The smoke qualitative analysis for noncontrolled lab-scale burning tests has primarily revealed: the presence of specific organic compounds indicative of incomplete wood combustion; the presence exclusively in “engineered” wood burning tests of pyrroles and amines, as well as the additional presence (as compared with “raw” wood burning) of further phenolic and containing nitrogen compounds; the potential impact of incomplete industrial wood burning on the photochemical smog phenomenon.

Phenyl acetic acid, a metabolite of 2-phenyl ethylamine, acts as a neuromodulator in the nigrostriatal dopaminergic pathway stimulating the release of dopamine. The evaluation of phenyl acetic acid concentration in the biological fluid reflects phenyl ethylamine levels thus allowing the assessment of the modulatory role of this endogenous substance. Changes in biological fluids levels of 2-phenylethylamine and/or in its metabolite have been reported in affective disorders, such as depression and schizophrenia. Recently, the occurrence of the "attention deficit hyperactivity syndrome" has been frequently reported in childhood population and involvement of dopaminergic dysfunction in this disease has been suspected. A fast, reliable and reproducible method for the determination of phenyl acetic acid in human blood, is therefore needed in order to have a screening tool for monitoring both healthy childhood population and suspected "attention deficit hyperactivity syndrome" patients. The gas chromatographic-mass spectrometric method here described makes use of a deuterated internal standard in order to overcome problems related to the lack of reproducibility often encountered when a derivatization step is performed.

The fate of enrofloxacin present in raw sewage at a swine-breeding facility was investigated by liquid-liquid extraction and reversed-phase liquid chromatography with photodiode array detection. Samples were collected in the storage pits of each pigsty and in a nonaerated lagoon used to stock the sewage. In the pigsties, the sewage was mixed with 10% olive oil groundwater, following a certified procedure (cod. Cer 020301) which reduces the bad odors and produces a better manure. This sewage treatment for 8 months in the lagoon dramatically reduced the amount of enrofloxacin to levels under the detection limit of 0.6 microg.L(-)(1). The results stress the importance of correct sludge management in limiting the impact of enrofloxacin in the environment.

A new, simple device generates accurate nano- and microflow rate gradients from any conventional HPLC system. The core of the new device is represented by an electric-actuated, computer-controlled, multiposition HPLC valve. The valve hosts six reservoirs for as many different mobile-phase compositions of increasing strength. A low flow rate stream pushes the weakest solvent through the column as long as required and at the desired flow rate, until the chromatographic run is started. From this time on, the electric actuation allows one to select which reservoir will be on-line with the column and for how long, thus generating a specific solvent gradient, through a sequence of controlled segments of precise mobile-phase composition. This permits one not only to exactly reproduce the programmed slope but also to achieve different gradient shapes (i.e., linear, convex, concave) for different separation needs. The new device has proven to be reliable and reproducible even at the lowest flow rate tested (250 nL x min(-1)) and in different chromatographic conditions.

Our recent on-line solid-phase extraction (SPE) device for micro-liquid chromatography, known as micro-solid-phase extraction (μSPE), was compared with traditional SPE for the analysis, from aqueous samples, of 4 pesticides belonging to different classes. Two different kinds of adsorbents, C18 and graphitized carbon black, were tested. A 2-stage ion trap mass spectrometer, equipped with homemade microflow electrospray ion (ESI) source, was used. Detection limits with a signal-to-noise ratio of 3:1 for both extraction methods were in the range of 0.1 μg/L for all compounds. However, better recoveries were obtained when μSPE traps were used.

Electron paramagnetic resonance (EPR) has been used to investigate the adsorption capability and the surface interacting ability towards Cu(II) solutions (CuCl2, Cu(NO3)2, CuSO4 in water or ethanol) of various carbon blacks, both graphitized and ungraphitized, selected on the basis of the surface area, namely, Carbograph1 (area=100 m2/g), Carbograph4 (area=210 m2/g), and Carbograph5 (area=560 m2/g), which were indicated as C1g, C4g, C5g (g=graphitized), and C1ng, C4ng, C5ng (ng=ungraphitized). The EPR analysis was supported by surface analysis, for evaluating the surface area, the pore volume and the porosity, and by atomic absorption to obtain the adsorbed Cu(II) amounts. Graphitization provokes a decrease in surface area, but C1g, at low surface area, showed a unexpected increase of the adsorption ability ascribed to the formation of new surface porosity closed by graphite layers. The carbon samples showed a broad unresolved EPR signal due to mobile unpaired electrons in the carbon matrix. Graphitized samples presented a narrower signal than ungraphitized samples, which increases in width with the increase in surface area (with the exception of C5ng due to the high exposition of the wide surface to oxydizing external agents) and upon prolonged thermal treatment. The signal intensity of the carbon paramagnetic centers decreases upon Cu(II) adsorption. Computer aided analysis of the EPR spectra of the solids after Cu(II) adsorption allowed to extract structural information on the Cu-surface site complexes. The Cu2+ ions coordinated with surface polar sites, mainly oxygenated. Adsorption depends on the different Cu(II) salts, caused by the salt solubility and the interacting ability of the counter-ion. In several cases the solutions concentrated in the carbon porosity leading to precipitation of the salt. Ethanol solutions are more adsorbed at the carbon surface than water solutions; Cu(II) partially retains its solvation shell and partially presents electron transfer to the carbon surface. Adsorption is favored to ungraphitized carbons with respect to the graphitized ones due to both the higher surface area, and the higher hydrophilicity of the surface. In summary, these carbon powders, widely used for chromatographic applications, show an adsorption capability towards Cu(II) solutions higher than expected due to both a definite porosity, and the presence of polar groups which are not eliminated with chemical surface treatments.

Mastic resin used as a covering film for painting protection was analyzed by electron paramagnetic resonance (EPR) spectroscopy, both as received and upon aging in sun-light. The effect of prolonged exposure to sun-light was mimicked by UV and, more so, by xenon lamp irradiation. Solid mastic presented EPR signals due to radicals trapped by PBN in solution. Data in the literature indicated the formation of acyl radicals (RCO·). These radicals preferentially dissolved in medium polarity solvents. The radical concentration in the solid mastic increased over time more than 50 times upon UV irradiation for 96 h and, even more, by xenon irradiation for 800 h. Also the PBN-trapped radicals in solution increased in concentration by irradiation. Small nitroxide radicals (TEMPO) interacted with a polar fraction of mastic dissolved in methanol, but mainly interacted with low polar mastic molecules in hydrophobic solvents. It was suggested, on the basis of both the PBN-spin trapping data and the TEMPO mobility variation in the solvents at different polarities, that terpenoid molecules partially polymerize by a radical mechanism to form low molecular weight products. A polyaromatic-radical (pyrene-TEMPO) and a biomolecule-radical (doxylcholestane) both interact weakly with mastic molecules in cyclohexane solutions. A positively charged surfactant radical (dimethylammonium-TEMPO bromide) was easily adsorbed onto the solid mastic surface suggesting that detergents are responsible for mastic degradation. In conclusion, this study provided information on the degradation mechanism of mastic resin and on its interacting ability towards external molecules and pollutants.

A new LC/MS method for the determination of organophosphorus pesticides in water, based on the use of direct-electron ionization (EI) interface, is presented. Direct-EI is a new device that, in a very simple fashion, couples a nano-HPLC system with a mass spectrometer equipped with electron ionization capability. The nanoscale liquid flow allows for a direct introduction of eluate into the ion source and, after nebulization, for its ionization under typical EI conditions. Library-matchable EI spectra are generated for a choice of full scan or SIM detection of the analytes. In our case, a selection of organophosphorus pesticides, commonly distributed in local sugar beet cultivation, were considered. The new interface permits a very sensitive detection of the analytes in a wide range of linear response (0.09-9 ng). When applied to a real sample, the method allowed detecting four different pesticides at a concentration level of approximately 3 ng x L(-1).

Chlorofluorocarbons and their replacement compounds are anthropogenic compounds of great environmental concern. For this reason monitoring their atmospheric mixing ratios on a worldwide scale is recommended. An analytical methodology for the simultaneous determination of selected chlorofluorocarbons and their replacement compounds has recently been developed. This methodology was applied in the analysis of actual air samples collected in remote and semi-remote areas located in the Northern and Southern Hemispheres. The concentration levels measured in the air samples collected in the two hemispheres are reported.

The use of a new LC-MS interface (cap-EI), part of a Waters Integrity system, capable of generating EI spectra at micro flow rates is presented. The cap-EI interface relies on the production of a fine aerosol by means of a nebulizer and supported by a nitrogen jet. Sensitivity, response linearity, reproducibility, and LC compatibility of the interface were thoroughly examined using testosterone, caffeine, a mixture of antiinflammatory drugs, and 3,4-dihydroxybenzoic acid as test compounds. The interface is fully compatible with LC requirements such as high-water- and/or -buffer-content mobile phases. Reproducibility, high sensitivity in scan mode, as well, to produce library-searchable EI spectra, 2 orders of magnitude linearity, together with an intrinsic simplicity of the entire system are the key features of cap-EI interface.

The simultaneous determination of chlorofluorocarbons and their replacement compounds in ambient air samples requires the preconcentration of appropriate air volumes on suitable adsorbents. The performance of a dual-layer adsorption tube to be used in this type of analysis was evaluated in terms of breakthrough volumes (BTV) for the compounds of interest at ambient temperature. To verify the effectiveness of such adsorption tubes, real air samples were enriched at ambient temperature and were subsequently analyzed by capillary gas chromatography coupled with quadrupole mass spectrometry, operating in SIM mode. The results obtained confirmed the efficacy of the proposed method, in terms both of sensitivity and chromatographic separation efficiency.

A capillary-scale particle beam interface was used to detect 18 phenolic compounds in red wine samples. This technique allows reproducible, library searchable electron ionization spectra at only 1 microliter/min mobile phase flow-rate for a sensitive detection of the analytes in complex matrices. The method makes use of a narrow bore, reversed-phase packed capillary column for sample separation. Detection limits were in the low picogram range for most compounds. Sensitivity and response linearity were evaluated for eight phenolic acids, which are often encountered in red wines. The phenolic compound composition was outlined in two red wines obtained using different aging processes.

This paper presents the results obtained using fused-silica fibers coated with graphitized carbon black (Carbograph-Alltech) for solid-phase microextraction (SPME). The extraction and calibration curves relative to organic micro-pollutants present in gaseous and aqueous samples are reported. Examples of applications of this extraction procedure to GC and GC-MS analysis of organic micro-pollutants in actual samples are also reported.

Coumarins are a large group of compounds that are naturally present in plant tissues and that exhibit a wide range of pharmacological properties. Analytical methods based on chromatographic techniques and conventional detectors are inadequate to accurately analyze coumarins in complex matrices such as plant extracts. In this article a new method based on a modified particle beam liquid chromatography-mass spectrometry interface is described. The method allows specific and accurate determination of several coumarins in biological matrices. An application regarding the analysis of 18 coumarins in the extract of Smyrnium perfoliatum L. is also reported.

Plastic tubing of polyetheretherketone (PEEK) is used for the preparation of HPLC packed capillary columns. The polymer is rigid but not fragile, has great resistance to chemical and physical agents and comes in standard 1/16″ O.D. These features can extend the column lifetime and facilitate the overall employment of HPLC capillary columns. Serial connection of short columns is also possible with no increase in dead volume. A new, rapid and effective packing method has been developed to be compatible with the characteristics of the material. Several C8 and C18 columns have been prepared and tested and some applications are shown.

The exceptional properties of graphitized carbon blacks in gas chromatography are described and the explanation of their behaviour is explained in terms of the thermodynamic functions related to the chromatographic process and of the k inetics of adsorption. Analytical applications u sing both packed and capillary columns using the working mechani sm of gas 1 i qui d solid chromatography are r eported.

A miniaturized, aerosol based interface for directly coupling a liquid chromatograph with a mass spectrometer is presented. The interface is entirely within the electron ionization (EI) source of the mass spectrometer and no additional, external devices are needed. This simple and effective approach exploits micro-flow nebulization technology providing a new interface suitable for a variety of applications of environmental and biological interest. The new interface provides necessary linearity, ruggedness, sensitivity, and reproducibility of response for trace level analysis, and readily interpretable mass spectra for unambiguous identification of unknown compounds of small to medium molecular weight.

The use of graphitized carbon black (GCB) cartridges for the extraction of organic pollutants (pesticides, phthalates, herbicides and polynuclear aromatic hydrocarbons) from water is discussed. Recovery tests carried out by spiking either the adsorbent or the water showed that nearly 100% recoveries can be obtained in most instances with 1 ml of a suitable eluent using 50 mg of GCB (Carbopack B). Examples of analyses of actual samples by gas chromatography—mass spectrometry are also shown. Levesl as low as 10 ppt can be determined.

A new procedure based on liquid-solid chromatography for the extraction of polynuclear aromatic hydrocarbons has been implemented. This yields results analogous to those of Soxhlet extraction for low molecular weight compounds. A very important reduction in the time required for sample preparation prior to gas chromatography/mass spectrometry analysis is obtained.

Thermodynamic data, such as the enthapy, entropy and free energy of sorption, were determined by adsorption gas chromatography on graphitized carbon blacks for C 3 C 6 n -alkanes and benzene. The data are compared with those available in the literature obtained by either gas chromatography or static methods. The adsorptive properties of graphitized carbon blacks were also evaluted by considering the changes in the isosteric heat of adsorption when a non-polar stationary phase (squalene) was added to the adsorbent.

The kinetic and thermodynamic changes induced in capillary columns with the internal area modified by a thin layer of graphitized carbon blacks are discussed and were tested experimentally. The selectivity due to the mechanism of gas—liquid—solid chromatography is greatly increased and the efficiency in terms of HETP is much improved at high linear gas velocities. This results in the possibility of obtaining faster analyses without the usual increase in operating temperature with respect to the gas—liquid technique. Examples of applications in practical analysis are given.