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The target sits at the core of each facility for the production of radioactive ion beams for nuclear physics research. The materials which constitutes it must withstand extremes conditions of temperature and pressure, being bombarded by intense beams of light particles for several days. This is particularly important in high-power facilities such as SPES (Selective Production of Exotic Species) in which the targets are subjected to strong thermal gradients. Accurate choice and design of materials are therefore crucial. On recent years, several studies have been carried out in the framework of the SPES target research and development. An overview of recently exploited production techniques and a selection of synthesized materials are presented.

Odorous compounds from a landfill have been characterised by gas-chromatography-mass-spectrometry, identifying about 100 volatile organic compounds. Air samples from different landfill sites and from the environment have been analysed after a solid-phase microextraction on a three-phase fiber, DVB/Carboxen/PDMS, which allowed a preconcentration and the chromatographic data obtained from the most significant emission sources have been submitted to chemometric analysis in order to better establish specific markers of olfactory pollution. For example limonene was a typical tracer of fresh wastes, while p-cymene was characteristic of leachate and biogas. By the developed analytical procedure it has been evaluated the efficiency of a scrubber plant utilised in the landfill in order to remove malodour compounds. The average removal efficiency was not very high (about 23.5%) due to scarce ability in removing low polarity compounds. Furthermore, it has been demonstrated the suitability of a microgas chromatograph for the continuous on-site monitoring of air pollution in order to rapidly individuate emission sources of olfactive nuisances.

Progabide, a new antiepileptic GABA agonist of moderate affinity for GABA receptors, has been studied in a number of psychiatric disorders and the results compared with the action of this drug in animal models. In an animal model for anxiety (the aversive response to periaqueductal grey stimulation in the rat) progabide had a similar action to that of diazepam. However in clinical trials to date the effect of the GABA agonist was inferior to that of benzodiazepines. As progabide diminishes both the nigrostriatal dopamine neuron activity and the effects of striatal dopamine receptor activation, a trial in schizophrenic patients was undertaken. Progabide was devoid of any evident antipsychotic action. However a certain improvement in responsiveness to the environment and in social interactions was noticed in hebephrenic and shizoaffective syndromes. This lack of antipsychotic effect of progabide may be a reflection of the weak activity of GABA agonists on limbic dopamine neurons. In these various clinical trials a definite improvement of affect and mood was noted in those patients receiving progabide. In clinical trials in depressed patients progabide produces a significant reduction in depressive symptoms, an action similar to that of imipramine both for the global clinical rating and the HRSD. This antidepressant activity is reflected by the action of progabide in behavioural models of depression such as olfactory bulbectomy, learned helplessness and the sleep-wake cycle.

The uptake of imipramine- 14 C, desipramine- 14 C, amitriptyline- 14 C and chlorimipramine- 14 C was studied in rat isolated atria incubated in a medium containing concentrations of the drugs ranging from 10 −8 to 10 −5 M: the tissue levels were linearly related to the concentration in the incubation medium, the four lines sharing almost the same equation: accumulation appeared to be a passive unsaturable process for each drug. Desmethyldoxepin, desmethyl-chlorimipramine, nortriptyline were 4–5 times less potent than desipramine in inhibiting l- 3 H-noradrenaline uptake, while the tertiary amines (imipramine, amitriptyline, chlorimipramine and doxepin) were far less potent. Apart from desipramine, which showed some sympathomimetic activity, the main effect of the drugs was a slowing of the spontaneous atrial rate which was more evident for the dimethyl than for the monomethyl compounds. All drugs potentiated l-noradrenaline chronotropic response to varying degrees, but the potentiation of noradrenaline response was not always correlated with the inhibition of its uptake. Thus, inhibition of uptake is not a valid parameter for prediction of noradrenaline potentiation and vice versa. Drug tissue concentrations correlated with l- 3 H-noradrenaline uptake inhibition but not with potentiation of l-noradrenaline chronotropic response.

I.p. administration of d-amphetamine sulphate and fenfluramine · HCl at various doses induced significant modifications of brain noradrenaline (NA) and MOPEG-SO4 (3-methoxy-4-hydrorxyphenylethyleneglycol) in the rat. Both drugs induced a decrease in brain noradrenaline but the two compounds seem to interact with the central noradrenergic system through a different mechanism. The decreased levels of noradrenaline after 1-fenfluramine administration were paralleled by increased MOPEG-SO4 levels. The d-isomer of fenfluramine was less active than the l-isomer. Amphetamine was considerably more effective than 1-fenfluramine in reducing NA concentration. However, in spite of the long lasting effect on noradrenaline levels the i.p. administration of amphetamine did not lead to an increased MOPEG-SO4 concentrations suggesting a more complex interaction with the noradrenergic system.

(1) The concentrations of various anticonvulsants (PB, PHT, CBZ, VPA) were measured in brain specimens from 7 patients who had undergone neurosurgery for a therapy resistant epilepsy of tumoral origin (astrocytoma) in 6 cases, glioblastoma in 1 case). (2) Great interindividual variability of the mean brain/plasma concentration ratios was observed for PB in 5 patients (range: 0.4-1.0). A mean brain/plasma ratio of 1.0 was recorded for PHT and CBZ (one patient each). (3) In the different tissue specimens (7-14) from the same patient AED concentrations varied greatly, even in neighboring areas. (4) Intraindividual variations were more marked in the present group of patients than in previously studied non-tumoral epileptics. (5) No correlation was found between the localization of the lesions and the variations in AED concentrations. (6) Brain AED concentration appeared to be higher in the few samples of non-tumoral tissue and lower in the 'epileptogenic' areas as defined by stereo-EEG seconding. (7) On the basis of these data, the hypothesis can be formulated that the therapy resistance of these patients may be at least partly explained by the presence of low AED concentration (even in presence of 'therapeutic' AED plasma levels) in the epileptogenic areas.

Carbamazepine (CBZ) binding by human plasma proteins was studied by means of three different techniques : ultrafiltration, equilibrium dialysis and MSA (Microspheres of Serum Albumin). The validity of the new MSA procedure for determining binding parameters was confirmed. The effects of plasma dilution and of temperature were also investigated. The association constant for albumin was found to be relatively low : 1.35 × 10 3 l/mole with an n value of 1.06 sites/mole. The data suggest that other proteins may be implicated in CBZ binding by human plasma. For concentrations within the therapeutic range (5–30 μg/ml) the unbound fraction of CBZ was 24%.

1. GABAergic mechanisms have been generally ignored in the study of mood disorders and antidepressant drug (AD) action. Recently data have accumulated indicating that GABAergic mechanisms may be involved in both of these. 2. Mood disorders: GABA levels are reported to be low in the CSF and plasma of depressed patients and are related to mood changes. GABA B receptors are decreased in the frontal cortex in two rodent behavioral models of depression and GABA release is reported diminished in the hippocampus. GABAergic drugs (progabide, fengabine) reverse the behavioral deficits in the rodent models and exert clear therapeutic effects in depressed patients. 3. AD action: In behavioral models imipramine upregulates GABA B receptors only in those animals which respond behaviorally to the AD. In naive rats repeated administration of varied ADs upregulates GABA B receptors in the frontal cortex whereas non-ADs (including amphetamine) do not. Bicuculline inhibits the action of imipramine in the learned helplessness model. GABA A receptor stimulation enhances noradrenaline release in the ventral NA pathway. 4. Conclusions: GABAergic mechanisms likely play a role in the modulation of mood and increasing GABAergic tone exerts an antidepressant effect. Actions at GABA synapses appear to be a fundamental facet of ADs, perhaps together with s-adrenoceptor mediated events.

The interaction of 1-butene with V 2 O 5 and VP mixed oxides has been investigated by the temperature-programmed desorption (TPD) technique. In V 2 O 5 and β-VOPO 4 four different types of center have been identified which desorb 1-butene as 2-butenes, furan, acetic acid, and maleic anhydride, respectively. In the case of (VO) 2 P 2 O 7 , four types of center have been identified which desorb 1-butene as 2-butenes, furan, acetic acid, and crotonaldehyde. With a mixture of (VO) 2 P 2 O 7 and amorphous V(V) phosphate, these types of center were absent. On the basis of a comparison between the TPD data and those obtained from 1-butene oxidation both in the presence and in the absence of oxygen, it is proposed that (VO) 2 P 2 O 7 and β-VOPO 4 are responsible for allylic oxidation and maleic anhydride formation, respectively.

A procedure for determining carbamazepine in biological specimens both from animals and humans is described. Carbamazepine was found to enter the brain relatively rapidly and its distribution is uniform through the body. In animals absorption and tissue distribution was found to be influenced to a certain extent by the vehicle employed. A clear correlation between the brain levels and the protection towards maximal electroshock was observed. Preliminary data on humans suggest a relatively slow absorption. An oral dose of 6 mg/kg gives plasma levels comparable to the ones obtained after an administration of 400 mg/kg in rats.

A method to measure butyrophenones as such in GLC was developed and applied for the determination of these drugs in biological materials. Haloperidol and trifluperidol show many properties in common when they are injected. They penetrate very rapidly into brain where they reach levels several times higher than in plasma. The brain concentration able to inhibit completely the effects of amphetamine is for both drugs between 30 and 40 ng/g. Haloperidol and trifluperidol are different in their capacity to accumulate in the adipose tissue in vivo and in vitro. The GLC method to measure butyrophenones has been employed for determining haloperidol in the plasma of psychiatric patients treated with this drug for therapeutical reasons.

Levels of diphenylhydantoin (DPH) and phenobarbital (PB) in plasma and brain of rats after single or combined, acute or chronic treatment have been determined. The results obtained indicate (a) drug plasma levels are not always a reliable index of brain levels because DPH disappearance from plasma is frequently more rapid than from brain; (b) DPH administration enhances the plasma and brain levels of PB; (c) levels of DPH or PB in brain correlate with the protection against a maximal electroshock.

Tryptophan injected intracerebrally in rats increases the level of brain serotonin. This increase occurs also in animals pretreated with reserpine or with a monoamineoxidase inhibitor. Other studies show that tryptophan, tryptamine or 6-hydroxytryptamine are not interfering in the determination of brain serotonin.

A variation in the rate of disappearance from plasma, at different times of the day, has been observed for exogenous Cortisol in humans after i.v. administration. This appears to correlate with the endogenous cortisol plasma levels. The possibility of a circadian fluctuation of drug metabolizing enzyme activities in man is discussed.

A sensitive and specific method for the quantitative determination of imipramine in human biological fluids is described. After extraction with n -hexane, imipramine is detected by gas-liquid chromatography-mass fragmentography. The procedure permits routine analysis on relatively small amounts of plasma (1–2 ml) containing as little as 10 ng/ml of imipramine without any interference from endogenous substrates.

A gas chromatographic method for the determination of propranolol in plasma has been developed. After solvent extraction, a difluorobutyrate derivative is formed, which is measured by an electron capture detector. The quantification is controlled by using an internal standard, pronethalol, which is added to all samples. The electron capture detector response was linear between 5 and 80 ng/ml. No interference from common cardiovascular drugs was found. Concentrations of propranolol in the plasma determined by this method were directly related to the administered dose of the drug.

The effect of DMI on the absorption of orally administered phenylutazone was studied in human subjects. A single pretreatment with 50 mg of DMI delayed the time to peak absorption of phenylbutazone in 4 volunteer subjects. Peak phenylbutazone plasma levels in untreated subjects were reached 2–6 hr after oral phenylbutazone administration while peaks were not attained even 10 hr after DMI treatment. A seven-day chronic pretreatment with DMI (25 mg, 3 X day) delayed time to peak absorption of phenylbutazone in 4 chronically depressed females from 2 hr (before DMI) to 4–10 hr when phenylbutazone was administered 30 min after the last dose of DMI. When phenylbutazone was given 14 hr after the last dose of a ten-day chronic treatment with DMI (25 mg, 3 X day) to another group of 4 females, no clear effect on the time to peak absorption was observed although plasma levels of phenylbutazone were lower in all 4 patients. The individual differences in phenylbutazone plasma levels may be due to individual variations in the metabolism of DMI.

I.p. administration of piribedil methansulphonate to male Sprague-Dawley rats resulted in a remarkable increase of brain MOPEG-SO4 which was consistent over time. In parallel experiments brain content of NA was found significantly reduced 30 and 60 min after drug administration. The effect seems to be dose dependent. These data cast some doubts on the relative specificity of action of piribedil as a dopaminergic activator.

Directive 2000/53/EC sets a goal of 85% material recycling from end-of-life vehicles (ELVs) by the end of 2015. The current ELV recycling rate is around 80%, while the remaining waste is called automotive shredder residue (ASR), or car fluff. In Europe, this is mainly landfilled because it is extremely heterogeneous and often polluted with car fluids. Despite technical difficulties, in the coming years it will be necessary to recover materials from car fluff in order to meet the ELV Directive requirement. This study deals with ASR pretreatment and pyrolysis, and aims to determine whether the ELV material recycling target may be achieved by car fluff mechanical separation followed by pyrolysis with a bench scale reactor. Results show that flotation followed by pyrolysis of the light, organic fraction may be a suitable ASR recycling technique if the oil can be further refined and used as a chemical. Moreover, metals are liberated during thermal cracking and can be easily separated from the pyrolysis char, amounting to roughly 5% in mass. Lastly, pyrolysis can be a good starting point from a “waste-to-chemicals” perspective, but further research should be done with a focus on oil and gas refining, in order both to make products suitable for the chemical industry and to render the whole recycling process economically feasible.

Bulk depositions and surface soil were collected in a suburban area, near the Adriatic Sea, in order to assess the contribution of a municipal solid waste incinerator to the area's total contamination with polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs and PCDFs). Samples were collected at two sites, situated in the area most affected by plant emissions (according to the results of the Calpuff air dispersion model), and at an external site, considered as a reference. Results show that the studied area is subject to low contamination, as far as these compounds are concerned. Deposition fluxes range from 14.3 pg m(-2)d(-1) to 89.9 pg m(-2)d(-1) (0.75 pg-TEQ m(-2)d(-1) to 3.73 pg-TEQ m(-2)d(-1)) and no significant flow differences are observed among the three monitored sites. Total soil concentration amounts to 93.8 ng kg(-1) d.w. and 1.35 ng-TEQ kg(-1)d.w, on average, and confirms a strong homogeneity in the studied area. Furthermore, from 2006 to 2009, no PCDD/Fs enrichment in the soil was noticed. Comparing the relative congener distributions in environmental samples with those found in stack emissions from the incineration plant, significant differences are observed in the PCDD:PCDF ratio and in the contribution of the most chlorinated congeners. From this study we can conclude that the incineration plant is not the main source of PCDD/Fs in the studied area, which is apparently characterized by a homogeneous and widespread contamination situation, typical of an urban area.

Car fluff is the waste produced after end-of-life-vehicles (ELVs) shredding and metal recovery. It is made of plastics, rubber, glass, textiles and residual metals and it accounts for almost one-third of a vehicle mass. Due to the approaching of Directive 2000/53/EC recycling targets, 85% recycling rate and 95% recovery rate in 2015, the implementation of automotive shredder residue (ASR) sorting and recycling technologies appears strategic. The present work deals with the characterization of the shredder residue coming from an industrial plant, representative of the Italian situation, as for annual fluxes and technologies involved. The aim of this study is to characterize ASR in order to study and develop a cost effective and environmentally sustainable recycling system. Results show that almost half of the residue is made of fines and the remaining part is mainly composed of polymers. Fine fraction is the most contaminated by mineral oils and heavy metals. This fraction produces also up to 40% ashes and its LHV is lower than the plastic-rich one. Foam rubber represents around half of the polymers share in car fluff. Moreover, some chemical-physical parameters exceed the limits of some parameters fixed by law to be considered refuse derived fuel (RDF). As a consequence, ASR needs to be pre-treated in order to follow the energy recovery route.

The effect of leaching rain on the corrosion behaviour of bronze UNSC83600 was investigated as to the influence of alloying elements (Cu, Sn, Zn, Pb) through dropping tests simulating a severe runoff condition with a solution reproducing natural acid rain. Corrosion was followed with time monitoring both samples and leaching solutions (up to 30 days) by SEM, EDS, Raman spectroscopy, XRD, AAS. The bronze patina behaves as a porous layer enriched in stable tin compounds allowing uniform dissolution of Cu, Zn and partly of Pb. Laboratory results are in good agreement with field studies of outdoor bronzes in unsheltered condition.

Bottom and fly ashes coming from the urban wastes incineration represent a by-product nowadays landfilled. By mixing different amount of these residues with others inert materials, such as glass cullet and feldspar waste, two vitrifiable mixtures are tailored. Glasses, obtained by means of vitrification process, are chemically stable with low leachability of contaminants and show comparable properties to those of commercial soda-lime glasses. Moreover, from the thermal and mechanical characterisation the tendency of these glasses to crystallise, for their transformation into glass-ceramic materials, has been evidenced.

The electrokinetic remediation was studied to verify the possibility to reclaim the bottom ash from municipal solid waste incineration (MSWI). In Italy, a production of 1 million tons per year of this kind of residue has been estimated, 90% of which is still landfilled. This work shows the results of four electrokinetic remediation tests for the removal of Pb, Cu, Zn, Cd and chlorides, using an open cell with graphite electrodes and without enhancing agents. The four tests have, respectively, been performed at a constant current density of 0.89, 1.67, 2.04 and 2.48 mA cm−2, with duration of 42, 68, 47 and 40 h. Heavy metals occur in ashes in various forms, such as exchangeable, adsorbed, precipitated, organically complexed and residual phases. In order to determine the nature of any given system, in terms of specific chemical species and pertaining mobilities, sequential extraction analyses have been performed. The release of pollutants was investigated for treated and untreated ash. After treatment, the concentration of pollutants in the leachate was reduced by 31–83%, better results being obtained for chlorides. Both the low amount of heavy metal extracted and the increase of ash pH during the electrokinetic tests, suggest to use enhancing agents or a cation exchange membrane at the cathode, to prevent the precipitation of metals as hydroxides.