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As manned spaceflights beyond low Earth orbit are in the agenda of Space Agencies, the concerns related to space radiation exposure of the crew are still without conclusive solutions. The risk of long-term detrimental health effects needs to be kept below acceptable limits, and emergency countermeasures must be planned to avoid the short-term consequences of exposure to high particle fluxes during hardly predictable solar events. Space habitat shielding cannot be the ultimate solution: the increasing complexity of future missions will require astronauts to protect themselves in low-shielded areas, e.g.during emergency operations. Personal radiation shielding is promising, particularly if using available resources for multi-functional shielding devices. In this work we report on all steps from the conception, design, manufacturing, to the final test on board the International Space Station (ISS) of the first prototype of a water-filled garment for emergency radiation shielding against solar particle events. The garment has a good shielding potential and comfort level. On-board water is used for filling and then recycled without waste. The successful outcome of this experiment represents an important breakthrough in space radiation shielding, opening to the development of similarly conceived devices and their use in interplanetary missions as the one to Mars.

An ion-interaction HPLC method is developed for the determination of mescaline in some Cactaceae species, namely Gymnocactus beguinii, Echinocactus polycephalus, Coriphanta radians, Coriphanta scolymoides, Coriphanta palmeri, Lophophora williamsii and Trichocereus pachanoi.Mescaline is characterized by hallucinogenic properties and can be prescribed as a psychodrug.The method makes use of a C18-reversed-phase as the stationary phase and of a 5.0 mM aqueous solution of octylamine o-phosphate as the mobile phase, with spectrophotometric detection at 230 nm.The method is sensitive (detection limit of 35 g/L) and matrix interference-free.The pretreatment of the sample is performed by grinding the fresh cactus and extracting the jelly pulp obtained either with a methanolic-ammonial solution or an aqueous solution buffered at pH 4.0 (phosphate buffer).The average amounts of mescaline found in Lophophora williamsii and in Trichocereus pachanoi were respectively 2.55 mg and 3.10 mg/g of fresh cactus.

The paper reports analytical data concerning water samples in Venice lagoon collected in different geographical sites, characterized by different salinity and kind of pollution. Chloride, iodide, bromide, sulfate, nitrite, nitrate were determined by means of ion-interaction chromatography, while phosphate determination was performed spectrophotometrically.The results are discussed with reference to literature data.

The RP-HPLC technique has been applied to the analysis of the flavonoid content of leaf extracts from various genotypes ofPopulus nigra andPopulus deltoides and from several of their hybrids. Two elution procedures different either as regards gradient program or the type of organic modifier used were checked to optimize the reliability of the results obtained. Before making any identification, the chromatographic profiles proved so typical of each species as to allow of their use as fingerprints in this type of taxonomic problem. Individual identifications were carried out by spiking real samples with known amounts of standard substances. The presence of flavonoid compounds previously identified was confirmed and a few new identifications were proposed.

Capillary SFC with supercritical CO2 as mobile phase and flame ionization detection was adopted to separate and determine triacylglycerols in vegetable and fish oils. The effect on separation of many experimental variables has been checked along with the selectivity of several stationary phases of different polarity. A standard mixture of 13 triacylglycerols was used to optimize the procedure and their retention times were used as reference to identify peaks in real samples. In spite of the fact that many peaks remained unidentified, the chromatograms obtained were useful as fingerprint analyses of the real samples examined.

An ion interaction method is presented for the simultaneous separation of herbicides belonging to different structural classes. Phenylurea-, triazine- and phenoxyacid derivatives are considered and the method is applied in the analysis of typical Italian soils characterized by different composition.

An ion-interaction reverse phase chromatographic method is presented for the separation and determination of atrazine, hexazinone, prometryn, propazine, simazine, terbuthylazine. The separation is carried out in isocratic conditions on a octadecyl silica stationary phase, using an hydroorganic solution (acetonitrile/water 45/55) of 5.0 mmol/L octylamine o-phosphate at pH 6.4 as mobile phase, with spectrophotometric detection at 230 nm. The detection limit (around 1.0 μg/L) reached without derivatization makes the method suitable for the analysis of surface waters without preconcentration. Application to river and lagoon water samples are reported.

The dependence of retention on pH of the mobile phase is investigated in reversed-phase ion interaction chromatography, being the mobile phase an aqueous solution of 5.0 mM octylammonium and ortho-phosphoric acid at different pH values.The analytes considered were amines, diamines, amides, and species characterized by different functionalities. The behaviour of retention as a function of pH is discussed with comparison with literature data and correlation with pka values is shown.The optimization of separation and resolution in a mixture of acids and amines through pH variations is also presented.

Ibotenic acid and muscimol are considered the principal components responsible of the hallucinogenic properties of Amanita muscaria. In this paper a sensitive ion-interaction HPLC method is presented which permits the simultaneous determination of ibotenic acid and muscimol. A C18 reverse phase is the stationary phase and the mobile phase is an aqueous solution of 5.0 mM octylammonium o-phosphate. A spectrophotometric comparative detection performed at 230 and 254 nm is employed. Detection limits are of 18 μg/L for ibotenic acid and of 30 μg/L for muscimol.

Measurements of thallium levels in Antarctic snow samples collected in an area surrounding the Italian Station at Terra Nova Bay in different campaigns have been performed without preconcentration by means of Laser Induced Atomic Fluorescence Spectroscopy (LIAF) as well as by High Resolution Inductively Coupled Plasma Mass Spectrometry (HR ICP-MS).The data obtained by both methods compare favourably and are of the order of tenths of pg/g. The data is discussed taking into account the effect of the marine aerosol and the crustal contribution to the thallium content in samples.

An ion-interaction HPLC method is developed for the separation of the phenylurea herbicides asulam, diuron, isoproturon, linuron and monuron. C 18 was used as stationary phase and octylammonium phosphate as ion-interaction reagent, in the presence of methanol or acetonitrile as organic modifier. Detection limits lower than 9 μg/l can be obtained without preconcentration steps. The method was applied to the analysis of diuron in a sample of lagoon water. Using liquid-liquid extraction, a diuron concentration of 42 μg/l was found.

The effect of tide on composition of Venice lagoon water is studied. At this purpose the concentration of phosphate, silicate, nitrite, nitrate, iodide, bromide and sulfate has been determined for a series of samples of lagoon water, collected in the same station every two hours during a sampling time of twenty two hours. Correlations between concentration and tide behaviour are drawn out.

Reversed-phase high performance liquid chromatography with diode array detection was used to analyze phenolic compounds contained in bark extracts of two different poplar clones known to have different resistance toDiscosporium populeum infection. Statistical treatments both monovariate and multivariate were applied to the results in order to identify regularities useful to discriminate the polar resistance and to check the importance of seasonal and cultivation site related factors. For the two clones examined phenolic compounds showed great discrimination ability not influenced by either sample collection period or cultivation site.

Chromatographic separations of complex phenol mixtures are accomplished using different elution conditions on three diverse stationary phases. The best resolution is obtained on a C18 stationary phase; 28 phenolic compounds are separated in a single run. An optimized cleanup and preconcentration procedure based on liquid-liquid extraction with methylene chloride is set up. Identification of the individual substances is made highly reliable by using multidimensional chromatography.

The dependence of retention on temperature in reversed-phase ion-interaction chromatography is investigated. 5mM octylammonium o-phosphate in aqueous solution is used as the interaction reagent, and retention of analytes characterized by different chemical properties is considered in the temperature range of 25–55°C. Variation of the thermodynamic parameters of enthalpy and entropy for the transfer process of the solute from the mobile to the stationary phase are evaluated. The results indicate that the retention process proceeds in the temperature range investigated through only a single mechanism and that similar retention mechanisms characterize all the analytes studied, independent of their chemical structure.

The separation and determination of several steroidal substances are achieved with capillary supercritical fluid chromatography by using supercritical CO2 as mobile phase. Different stationary phases are used to compare chromatographic results, optimize the separation, and obtain information about the chromatographic behavior of the substances examined. Unexpected elution orders and problems of poor sensitivity of the flame-ionization detector towards some compounds are discussed. Alternative chromatographic conditions are explored: an electron-capture detector is used with suitably optimized pressure gradients in an attempt to overcome these limitations.

An ion-interaction reversed-phase chromatographic method is presented for the separation of 2,4-dichlorophenoxyacetic acid, 2-(2,4-dichlorophenoxy)propionic acid, 2,4,5-trichlorophenoxyacetic acid, 4-(2,4-dichlorophenoxy)butyric acid, 4-chloro-o-tolyloxyacetic acid, 4,6-dinitro-o-cresol, and 5-bromo-3-sec-butyl-6-methyluracil. These herbicides, which do not belong to the same functional classes, are characterized by different chemical properties, particularly in terms of hydrophilicity. The effect of mobile phase pH, organic modifier, ion-interaction reagent, and stationary phase packing material on analyte retention is investigated and discussed. The method permits detection at concentration levels less than 12 μg/L without preconcentration or pretreatment steps and is applied to the analysis of river water samples.