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This chapter describes the functionalization of the surface of the glass through thin film inorganic coatings. Such filters called dichroic filters, following the physical principle of interference of light using the rules of optical physics. The design of the optical multilayer materials with high and low refractive index and optimizing the predetermined optical responses. The AFM quantify the real thickness and, calibrate the deposition plant, using as an input data for the simulation to evaluate the dispersion index refraction and absorption. The dichroic filters separate the incident radiation into two or more predetermined optical bands. The materials used are deposited using PVD Reactive Magnetron Sputtering, allows to increase the deposition rate, to obtain good homogeneity range of the surface deposited. The set point of deposition which allows to obtain stoichiometric oxides is analyzed with the technique RBS. These optical filters, also called dichroic are applied in the research field of the splitting photovoltaic concentration.

Experiments were performed at the CERN SPS with 120 GeV/c stored proton beams to assess the possibility of beam halo collimation assisted by bent crystals. A bent crystal was used to deflect horizontally by an angle of about 170 mu rad the beam halo protons in channeling states directing them into a 60 cm long tungsten absorber. The halo loss rate due to nuclear inelastic interactions of protons in the aligned crystal was up to five times smaller than for its amorphous orientation. Channeled fractions, (75 +/- 4)% and (85 +/- 5)% for the two tested silicon crystals, were measured by intercepting the deflected beam with another collimator located between the crystals and the absorber. The pixel detector (MEDIPIX) installed in a Roman pot inside the beam pipe was used to obtain visual images of the deflected beam. (C) 2010 Elsevier B.V. All rights reserved.

Channeling in a short bent silicon crystal was investigated at the CERN SPS using 400-GeV/c protons with an angular spread much narrower than the critical channeling angle. Particle dechanneling due to multiple scattering on the atomic nuclei of the crystal was observed and its dechanneling length was measured to be about 1.5 mm. For a crystal with length comparable to such dechanneling length, an efficiency of 83.4% was recorded, which is close to the maximum value expected for a parallel beam and exceeds the previously known limitation of deflection efficiency for long crystals.

The optical sensing properties of nanometric polyimide films towards ethanol and methanol vapours have been investigated by surface plasmon resonance technique. To this purpose polyimide sensing layers have been deposited onto gold/glass substrates by glow-discharge-induced vapour deposition polymerization technique. The sensible layer shows reversible and stable responses to different concentrations of methanol and ethanol vapours. A linear dependence between the change in reflectivity and the vapours concentration is observed being the sensitivity to both vapours similar, however, the response is larger in presence of ethanol vapours. Numerical fitting routines on surface plasmon resonance curves indicate that optical changes are motivated by an absorption process of the analyte. This produces a detectable increase of the real refractive index and a swelling process in the polyimide layer.

Copper phthalocyanine (CuPc) thin films have been deposited by a recently developed plasma-based method named glow-discharge-induced sublimation (GDS). The deposition of CuPc films has also been ob...

Glow-discharge-induced sublimation (GDS) is used to deposit thin films of polyimide precursor monomers, i.e., 2,4,6-trimethyl m-phenylenediamine (TMPD), 4,4‘-hexafluoroisopropylidene dianiline (6FDAm), 3,3‘-diaminodiphenyl sulfone (DDS), 4,4‘-hexafluoroisopropylidene diphthalic anhydride (6FDA), and 3,3‘,4,4‘-biphenyltetracarboxylic acid dianhydride (BPDA). Monomer films are also deposited by vacuum evaporation (VE) for the sake of comparison. In situ mass spectrometry points out both the sublimation of integer monomer molecules and the presence of molecular fragments in the glow discharge. AFM images of the film surfaces indicate that GDS allows obtention of smoother surfaces with respect to VE for most of the monomers. FT-IR analysis and UV−Vis fluorescence spectroscopy show that the deposition of integer monomer molecules onto the substrate and the partial incorporation of molecular fragments take place. In particular, the fluorescence features of GDS samples are different from those of VE samples and ...

The glow discharge vapour deposition polymerisation method for the preparation of polyimide coatings is presented. This method involves the deposition of the monomer vapours onto a solid substrate in a vacuum chamber. The evaporation of the monomers is obtained by using standard radio frequency magnetron sputtering equipment: the monomer powders are placed on a sputtering source and bombarded by low energy He ions at pressures in the range of 10–20 Pa. By a momentum-transfer mechanism, the ions dissipate their energy causing target heating and sublimation of the monomer molecules. The emission of volatile species from the monomers target surface and their interactions with the plasma components are studied by mass spectrometry and optical emission spectroscopy. Polyimide coatings with thickness ranging from 200 nm to 3 μm have been deposited onto silicon single crystals, sapphire and polyimide substrates. SEM micrographs of these coatings show a homogeneous and crack-free surface. The as-deposited films are mainly made of a mixture of polyamic acid and non-reacted monomers, as revealed by Fourier transform infrared spectroscopy. The imide peaks clearly appear only after thermal treatment (typically 250°C, 1 h, in air or argon). The electrical properties of the polyimide coatings (i.e. bulk and sheet resistivity and dielectric breakdown voltage) are those typical of an insulating material and comparable with the commercial polyimide. These films are characterised by good adhesion to the silicon, sapphire and other polyimide substrates. Chemical resistance to some reagents (acetone, hydrogen peroxide, nitric and hydrofluoric acid) has also been tested.

Samples of albite feldspar were dissolved at 300C and 170 bars for periods up to 24 h in flow-through reactors at acid, neutral, and basic pH conditions. Three MeV ion beam techniques, Resonant Nuclear Reaction Analysis (RNRA), Rutherford Backscattering Spectrometry (RBS), and Elastic Recoil Detection Analysis (ERDA) were employed to obtain elemental depth profiles and information on the composition of the near-surface region after dissolution. Based on the anti-correlative trends of the H and Na profiles obtained by RNRA, Na loss and H permeation are coupled by an ion exchange process in acidic and neutral pH solutions. At basic pH conditions, the evidence is ambiguous as to whether there is a limited degree of ion exchange between aqueous cations and Na, as based on RBS spectra and Na RNRA profiles. The recorded depths of H permeation and Na leaching range from a maximum at acid pH (H permeation exceeding ∼10,000A, Na leaching ∼20,000A) to a minimum at basic pH (no H enrichment, Na leaching depths of several hundredA). The composition of the leached/H-enriched region is a function of pH. This is postulated to be primarily a function of two factors: the H ion concentration gradient between the solution and the solid, which directly controls the pH-dependence of the ion exchange couple H+ (or H3O+) ← Na+ and secondly, the speciation of Al -OH and t.sbnd; Si -OH groups created by hydrolysis reactions and the subsequent preferential release of Al within the leached/H-enriched zone. Based on the ratios of H uptake to Na loss at acid and neutral pH, which range between 0.7 and 2.5, it is not possible to distinguish between H+, H2O, and H3O+ species permeating into the structure. Free water may be created within the leached/ H-enriched structure via recondensation (repolymerization) reactions of adjacent Si&-OH groups. Excess H concentration profiles potentially provide indirect evidence for recondensation reactions at depths

Probability of inelastic nuclear interactions in a short bent silicon crystal for its orientations optimal for channeling and volume reflection was investigated using 400 GeV/c protons of the CERN SPS. The contribution of nuclear interactions from channeled protons was observed to be about 3–4% of the probability for the amorphous orientation. For the crystal orientation optimal for volume reflection the nuclear interaction probability of protons was a few percents larger than in the amorphous case. It was shown that in the limiting case of a quasi parallel beam realizing for the collider beam halo the inelastic nuclear losses should decrease by more than five times, which is an additional advantage of a crystal as a primary collimator for the LHC collimation system.

Different kinds of deflection in a silicon crystal bent along the 〈111〉 axis was observed for 150 GeV/ c negative particles, mainly π − mesons, at one of the secondary beams of the CERN SPS. The whole beam was deflected to one side in quasi-bound states of doughnut scattering (DSB) by atomic strings with the efficiency (95.4 ± 0.2)% and with the peak position close to the bend crystal angle, α = 185 μrad . It was observed volume capture of π − mesons into the DSB states with a probability higher than 7%. A beam deflection opposite to the crystal bend was observed for some orientations of the crystal axis due to doughnut scattering and subsequent multiple volume reflections of π − mesons by different bent planes crossing the axis.

Multiple volume reflections of the 400 GeV / c proton beam by the sequence of fourteen bent silicon strips has been studied at the CERN SPS. The sequence is close to be parallel that is the spread of the strip orientation angles is much smaller than their bend angle and eleven strips working coherently in the regime of volume reflections deflected the beam by 110 μrad with the efficiency 88%, which is significantly larger than the estimation based on independent reflections. The mechanism giving the efficiency increase has been studied by simulation. It appears that many particles volume captured in one of the strips take part in volume reflections in the subsequent ones. Such a crystal multi reflector can be successfully used as a primary collimator for the beam halo collimation of high-energy accelerators.

Multiple volume reflection by different planes in a bent silicon crystal with its 〈111〉 axis orientation close to the beam direction was observed for the first time for 400 GeV/c protons at the CERN SPS. The proton beam was deflected to the side opposite to the crystal bend by an angle of about 67 μrad, which is five times larger than in a single volume reflection by the (110) bent planes. The registered efficiency of one side deflection was about 84%. It was shown that multiple volume reflection transforms to a single volume reflection when the orientation angle of the 〈111〉 axis relative to the beam direction is increased.

Deflection due to planar channeling and volume reflection in short bent silicon crystals was observed for the first time for 150 GeV / c negative particles, π − mesons, at one of the secondary beams of the CERN SPS. The deflection efficiency was about 30% for channeling and higher than 80% for volume reflection. Volume reflection occurs, in spite of the attractive character of the forces acting between the particles and the crystal planes, in a wide angular range of the crystal orientations determined by the crystal bend angle.

Deflection due to axial channeling in a silicon crystal bent along the 〈111〉 axis was observed for 150 GeV/c negative particles, mainly π − mesons, at one of the secondary beams of the CERN SPS. The whole beam was deflected to one side with the efficiency of about 90% and with the peak position at the bend crystal angle α = 43 μrad . The deflection occurs mainly due to doughnut scattering of above-barrier particles by the atomic strings of the crystal. However, due to a high probability of particle recapture into bound states with the atomic strings their contribution to the deflection should be about 15% for our case according to simulation results.

The trend of volume reflection parameters (deflection angle and efficiency) in a bent (110) silicon crystal has been investigated as a function of the crystal curvature with 400 GeV/c protons on the H8 beam line at the CERN Super Proton Synchrotron. This Letter describes the analysis performed at six different curvatures showing that the optimal radius for volume reflection is approximately 10 times greater than the critical radius for channeling. A strong scattering of the beam by the planar potential is also observed for a bend radius close to the critical one.

This paper presents a detailed study of the deflection phenomena of a $400\text{ }\text{ }\mathrm{GeV}/c$ proton beam impinging on a new generation of bent silicon crystals; the tests have been performed at the CERN Super Proton Synchrotron H8 beam line. Channeling and volume reflection angles are measured with an extremely precise goniometer and with high resolution silicon microstrip detectors. Volume reflection has been observed and measured for the first time at this energy, with a single-pass efficiency as large as 98%, in good agreement with the simulation results. This efficiency makes volume reflection a possible candidate for collimation with bent crystals at the CERN Large Hadron Collider.

This paper presents a detailed study of the deflection phenomena of a 400 GeV/c proton beam impinging on a new generation of bent silicon crystals; the tests have been performed at the CERN Super Proton Synchrotron H8 beam line. Channeling and volume reflection angles are measured with an extremely precise goniometer and with high resolution silicon microstrip detectors. Volume reflection has been observed and measured for the first time at this energy, with a single-pass efficiency as large as 98%, in good agreement with the simulation results. This efficiency makes volume reflection a possible candidate for collimation with bent crystals at the CERN Large Hadron Collider.

The doubling of the angle of beam deflection due to volume reflection of protons by a sequence of two bent silicon crystals was experimentally observed at the 400 GeV proton beam of the CERN SPS. A similar sequence of short bent crystals can be used as an efficient primary collimator for the Large Hadron Collider.

A high performance apparatus has been designed and built by the H8-RD22 collaboration for the study of channeling and volume reflection phenomena in the interaction of 400 GeV/c protons with bent silicon crystals, during the 2006 data taking in the external beamline H8 of the CERN SPS. High-quality silicon short crystals were bent by either anticlastic or quasimosaic effects. Alignment with the highly parallel (8 murad divergence) proton beam was guaranteed through a submicroradian goniometric system equipped with both rotational and translational stages. Particle tracking was possible by a series of silicon microstrip detectors with high-resolution and a parallel plate gas chamber, triggered by various scintillating detectors located along the beamline. Experimental observation of volume reflection with 400 GeV/c protons proved true with a deflection angle of (10.4+/-0.5) murad with respect to the unperturbed beam, with a silicon crystal whose (111) planes were parallel to the beam.

Beam deflection due to axial channeling in a silicon crystal bent along the < 111 > axis was observed with 400 GeV/c protons at the CERN Super Proton Synchrotron. The condition for doughnut scattering of protons by the atomic strings of the crystal was attained. Such a condition allowed one to observe a beam deflection of 50 mu rad with about 30% efficiency. The contribution of hyperchanneled states of protons to the observed beam deflection was less than 2% according to simulation results.

High vacuum evaporation (VE) is used for the first time to grow thin films of novel tetraphosphonate, Tiiii[H, CH3, Ph], and tetrathiophosphonate, TSiiii[H, CH3, Ph], cavitands for gas sensing applications. The sublimation rate of the compounds was monitored during the depositions and related to the final physical properties of the samples. The properties of deposited films were investigated by various techniques. FT-IR and ESI-MS indicate that the samples consist of pristine cavitand molecules and demonstrate the high purity of the VE films. AFM images show the Tiiii and TSiiii films to possess similar thickness and globular morphology. These physical analyses indicate the uniformity and homogeneity of the final samples as well as the high reproducibility of the VE technique. The sensing capabilities of the samples were investigated by exposing Tiiii- and TSiiii-coated QCMs to ethyl alcohol in very low concentrations. The sensitivity, the speed, and the detection limit of the samples were determined, ind...

For the new generation of high intensity hadronic machines as, for instance, LHC, halo collimation is a necessary issue for the accelerator to operate at the highest possible luminosity and to prevent the damage of superconductor magnets. We propose an experiment aimed to systematic study of the channeling phenomenology and of the newly observed "volume reflection" effect. This experiment will be performed for an external SPS beamline and will make use of a primary proton beam with 400 GeV/c momentum and very small (∼ 3 μ rad) divergence. The advantage of a proposed experiment is precise tracking of particles that interacted with a crystal, so that to determine the single-pass effciency for all the processes involved. For this purpose, a telescope equipped with high-resolution silicon microstrip detectors will be used. New generation silicon crystals and an extra-precise goniometer are mandatory issues. Main goal of the experiment is to get the precise information on channeling of relativistic particles and, ultimately, on the feasibility of such technique for halo collimation at LHC. In this contribution we review the status of the setting-up of experimental apparatus and its future development in sight of the planned run in September 2006.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A novel soluble phthalocyanine compound, i.e zinc phthalocyanine (sulfonamide) has been synthesized by chemical substitution of zinc phthalocyanine and used to produce thin solid films by means of the spin coating technique. The chemical structure of the spin coated films has been investigated by FT-IR analysis. Atomic Force Microscopy (AFM) has been used to characterize the film morphology and to measure the film thickness. The spin coated films have been tested as optical sensing materials of volatile organic compounds such as methanol, ethanol and 2-propanol. The change of optical reflectance of the films upon exposure to alcohol-vapour-containing atmospheres has been measured versus alcohol concentration and exposure time. The films exhibit a fast and reproducible response, with a complete and fast recovery in methanol and ethanol-containing atmospheres, while diffusion-driven effects appear during exposure to 2-propanol. The response and sensitivity of the films to ethanol vapour is higher than to methanol and 2-propanol.

In this work novel 5,10,15,20 meso-tetraphenyl porphyrin (H 2 TPP) films have been deposited by means of a new physical technique named glow discharge induced sublimation (GDS). A preliminary characterization has been performed by means of scanning electron microscopy (SEM) and Fourier transform infra-red (FT-IR) analyses. SEM images and infra-red analyses highlight the great surface roughness and the high purity of GDS films, respectively. For comparison, H 2 TPP films have been also deposited by means of spin coating (SPIN) technique. Optical sensing measurements, performed in differently concentrated ethyl alcohol (EtOH) atmospheres, highlight that GDS samples yield higher response intensities than SPIN films, very short response times and complete recovery.

The volume reflection phenomenon was detected while investigating 400 GeV proton interactions with bent silicon crystals in the external beam H8 of the CERN Super Proton Synchrotron. Such a process was observed for a wide interval of crystal orientations relative to the beam axis, and its efficiency exceeds 95%, thereby surpassing any previously observed value. These observations suggest new perspectives for the manipulation of high-energy beams, e.g., for collimation and extraction in new-generation hadron colliders, such as the CERN Large Hadron Collider.

Pure and Nile-Red-doped polyimide and porphyrin films have been deposited and their optical response to different organic vapours has been tested. Polyimide films were obtained by spin coating a solution containing 4, 4'-4, 4'-(hexafluoroisopropylidene) diphthalic anhydride and 2, 3, 5, 6-tetramethyl-1, 4-phenylenediamine. Free, cobalt and iron chloride 5, 10, 15, 20 meso-tetraphenyl porphyrin films were deposited by spin coating and by high vacuum evaporation. Exposure to water, ethanol and isopropanol vapours produce reversible changes of the fluorescence features of both pure and doped polyimide films. Exposure to methanol, ethanol and isopropanol vapours gives rise to changes of the optical absorption of porphyrin films. The results of the optical measurements point out that the synthesized films can be used for the detection of volatile organic compounds.

Copper phthalocyanine films have been deposited by glow-discharge-induced sublimation. The films have undergone postdeposition heat treatments in air at 250 and 290 °C for different times, ranging from 30 min to 14 h. The properties of as-deposited and heated films have been investigated by different techniques in order to determine the effects of heat treatments on the film properties. Fourier transform infrared analysis and UV−visible optical absorption analysis point out a gradual evolution of the film structure from a mixture of α and β polymorphs to the only β polymorph in the sample heated at 290 °C for 14 h. A pronounced decrease of carbon and nitrogen atomic percentages against an oxygen increase in the heated films are shown by ion beam analyses (Rutherford backscattering spectrometry and nuclear reaction analysis) and X-ray photoelectron spectroscopy (XPS). X-ray absorption spectroscopy and XPS indicate that part of the copper phthalocyanine molecules decompose during heat treatments and the formation of copper oxide takes place. The replacement of copper phthalocyanine by copper oxide in the heated films accounts for the change of their surface electrical conductance and of their electrical response to NO2.

Bent crystals can be successfully applied for extraction/collimation of relativistic particles. A crucial feature to obtain high extraction efficiencies is the treatment of the surfaces being encountered by the beam, since mechanical operations induce considerable lattice imperfections. In order to remove the superficial damaged layer a planar etching can be applied on the surface exposed to the beam. This work presents a systematic study of the morphology and the crystalline perfection of the surface of the samples that have been used in accelerators with high efficiency. Crystals with different surface treatments have been investigated. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were applied on the characterisation of surface morphology. Low energy backscattering channeling of 2-MeV a particles or protons was used as a probe for the crystalline structure. The presence of a superficial damaged layer in the samples just after mechanical treatment was unveiled, while, in contrast, chemical etching leaves a surface with high crystalline perfection that can be related to the record efficiency. (c) 2006 Elsevier B.V. All rights reserved.

Thin films have been grown on silicon and silica substrates by cosputtering of silica and silver in Ar, Ar+2.5%O2, and Ar+5%O2 gas mixtures. Rutherford backscattering spectrometry showed that the films have Ag atomic fractions xAg in the range of ∼1to∼10at.%, and, by valence considerations, that the fraction of oxidized Ag in the films deposited in presence of oxygen is limited. Transmission electron microscopy images revealed the presence of Ag nanoclusters, with a mean size diameter not larger than 5nm. The clusters are preferentially arranged along columns. It is suggested that the columns are regions with diameter in the nanometer range in which the density of the dielectric matrix is lower, thus favoring the formation of metal clusters. In presence of O2, the clusters were observed to have a more regular spherical shape. The optical absorption spectra of films grown in presence of O2 are distinguished from those grown in Ar by specific features, which are attributed to oxidation at the cluster surface.

Ternary W-Si-N thin films have been reactively sputter-deposited from a W5Si3 target at different nitrogen partial pressures. The composition has been determined by 2.2 MeV 4He+beam, the structure by x-ray diffraction and transmission electron microscope, the chemical bonds by Fourier transform - infrared spectroscopy and the surface morphology by scanning electron microscopy. Electrical resistivity was measured by four point probe technique on the as grown films. The film as-deposited is amorphous with the Si/W ratio increasing from about 0.1 up to 0.55 with the nitrogen content going from 0 to 60 at%. The heat treatments up to 980 oC induce a loss of nitrogen in the nitrogen rich samples. Segregation of metallic tungsten occurs in the sample with low nitrogen content (W58Si21N21). Samples with high nitrogen content preserve the amorphous structure, despite of the precipitation of a more ordered phase inferred by FT-IR absorbance spectrum of the layer treated at highest temperature. The surface morphology depends upon the nitrogen content; the loss of nitrogen induces the formation of blistering and in the most nitrogen rich sample the formation of holes. Electrical resistivity preliminary results on the as grown layers range between 500 and 4750 μΩcm passing from the lowest to the highest N concentration.ACKNOLEDGMENTS The authors would like to thank Prof. G. Ottaviani for discussions and critical review of the manuscript, Dr. R. Tonini, M. Butturi and G. Das for the acquisition of several experimental results. Research supported by the MIUR project.

W–Si–N thin films were deposited via rf-magnetron sputtering from a W5Si3 target in Ar/N2 reactive gas mixtures over a large range of compositions, obtained by varying the partial flow of nitrogen within the reaction chamber. The samples of each set were then thermally annealed in vacuum at different temperatures up to 980 °C. Film composition was determined by Rutherford backscattering spectrometry (RBS), surface film morphology by scanning electron microscopy (SEM), micro-structure by transmission electron microscopy (TEM), vibrational properties by FT-IR absorption and Raman scattering spectroscopy, and electrical resistivity by four-point probe measurements. Independently of the deposition conditions, all the as-deposited films have an amorphous structure, while their composition varies, showing an increase of Si/W ratio from 0.1 up to 0.55 when the nitrogen concentration in the films increases from 0 to 60 at%. Thermal treatments in vacuum induce an important loss of nitrogen in the nitrogen-rich samples, especially at temperatures higher than 600 °C. Samples with high nitrogen content preserve their amorphous structure even at the highest annealing temperature, despite the chemical bonding ordering observed by means of FT-IR measurements. Raman spectroscopy of as-deposited films rich in nitrogen suggests the presence of an important amorphous silicon nitride component, but fails to detect any structural rearrangement either within the composite matrix of film or within silicon nitride component. Segregation of metallic tungsten was detected by TEM in the annealed sample with lowest nitrogen content (W58Si21N21). Finally, the resistivity of the films increases with the N content, while the loss of nitrogen accompanies the decrease of resistivity especially of samples with high nitrogen content.

Erratum to : "Double volume reflection of a proton beam by a sequence of two bent crystals" [Phys. Lett. B 658 (2008) 109] (DOI:10.1016/j.physletb.2007.10.070)

Lead silicate glass films were deposited on sapphire substrates in different plasmas (100% Ar; 20% H2+ 80% Ar; 5% O2+ 95% Ar) by reactive radio-frequency magnetron sputtering. The stoichiometry of the films, determined by Rutherford backscattering spectroscopy, changed with the deposition conditions. X-ray diffractometry analysis showed the presence of metallic Pb in the samples sputtered in H2-containing plasma. The room-temperature sheet resistance of the films ranged from >1016Ω/□ (O2-containing atmosphere) to about 103Ω/□ (H2-containing atmosphere).

Effects of lead ion implantation on the dissolution behavior of amorphous silicates and various minerals in the selective dissolution regime have been investigated by means of ion beam analytical techniques. We show that an enhanced hydration and a marked elemental redistribution occur for a critical dose ~ 5 x 1013 ions cm-2. We pinpoint the usefulness of these techniques in mineral dissolution and weathering studies., Nous avons étudié les effets d'une implantation d'ions de plomb sur les caractéristiques de dissolution de silicates amorphes et de divers minéraux en régime de dissolution sélective, au moyen de techniques d'analyse par faisceaux d'ions. Nous montrons l'existence d'une hydratation accrue et d'une remobilisation élémentaire notable au delà d'une dose critique ~ 5 x 1013 ions cm-2. Nous soulignons l'intérêt de ces techniques pour les études de dissolution et d'altération des minéraux., Petit Jean-Claude, Dran Jean-Claude, Della Mea Gianantonio. Effects of ion implantation on the dissolution of minerals. Part II : selective dissolution. In: Bulletin de Minéralogie, volume 110, 1, 1987. pp. 25-42.

In this paper new data on the dissolution of various silicate minerals (quartz, albite, olivine) are presented, obtained by means of MeV ion beam techniques (resonant nuclear reactions and Rutherford backscattering spectrometry), which allow surface chemical analysis of solids. The main result of this study is the evidence that dissolution of silicate minerals can proceed via a marked surface hydration. It is shown that ion beam techniques are very effective to study the mechanisms of mineral dissolution.

5,10,15,20 meso-tetraphenyl porphyrin (H2TPP) and copper phthalocyanine (CuPc) films have been deposited by means of a recently developed plasma based technique named glow discharge induced sublimation (GDS). The two macrocycles have been deposited by vacuum evaporation (VE) and H2TPP by spin coating (SPIN) as well for comparison. The physical properties of the films have been characterized by means of scanning electron microscopy (SEM) and nitrogen physisorption measurements. SEM images and physisorption isotherms highlight both the much higher surface roughness and specific surface area of GDS samples with respect to the VE and SPIN ones. Optical sensing measurements, performed in differently concentrated ethyl alcohol atmospheres, highlight that GDS samples yield much higher response intensities than SPIN and VE films, short response times and complete recovery.

Hydrogen in RuOx layers on quartz prepared by the thermal decomposition of RuCl3 has been detected by means of a nuclear technique. RuOx absorbs water rapidly from the liquid and a constant H/Ru ratio is found throughout the thickness of the layer. RuOx also absorbs water from the ambient moisture, but no saturation is observed even after several months. The permeability of RuOx to water is explained in terms of grain boundary diffusion.