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We propose the use of Focused Ion Beam/Scanning Electron Microscope (FIB/SEM) devices for the analysis of ablation results. Ablated samples have been obtained by irradiating an Al planar target with an optically smoothed iodine laser working at 0.44 mu m. The interpretation of FIB images shows the high potentiality of the technique.

Carbon fiber composite (CFC) targets are investigated by a focused ion beam/scanning electron microscope (FIB/SEM) in a joint project aiming at the development of robust divertors in the International Thermonuclear Experimental Reactor (ITER). These mockups are exposed to a plasma that simulates the off-normal thermal loads foreseen for ITER and display a rich, puzzling impact scenario. Morphological elements are identified at the exposed surface and beneath it, and are examined in order to point out the relevant processes involved. Each technique adopted is discussed and evaluated

We propose the use of Focused Ion Beam/Scanning Electron Microscope (FIB/SEM) devices for the analysis of ablation results. Ablated samples have been obtained by irradiating an Al planar target with an optically smoothed iodine laser working at 0.44 mu m. The interpretation of FIB images shows the high potentiality of the technique.

Focused ion beam (FIB) techniques are among the most important tools for the nanostructuring of surfaces. We used the FIB/SEM (scanning electron microscope) for milling and imaging of digestive gland cells. The aim of our study was to document the interactions of FIB with the surface of the biological sample during FIB investigation, to identify the classes of artifacts, and to test procedures that could induce the quality of FIB milled sections by reducing the artifacts. The digestive gland cells were prepared for conventional SEM. During FIB/SEM operation we induced and enhanced artifacts. The results show that FIB operation on biological tissue affected the area of the sample where ion beam was rastering. We describe the FIB-induced surface major artifacts as a melting-like effect, sweating-like effect, morphological deformations, and gallium (Ga+) implantation. The FIB induced surface artifacts caused by incident Ga+ ions were reduced by the application of a protective platinum strip on the surface exposed to the beam and by a suitable selection of operation protocol. We recommend the same sample preparation methods, FIB protocol for milling and imaging to be used also for other biological samples. © 2007 Wiley-Liss, Inc.

The aim of this paper is to show how a focused ion beam combined with a scanning electron microscope (FIB/SEM machine) can be adopted to characterize composite fibers with different electrical behavior and to gain information about their production and modification. This comparative morphology investigation is carried out on polyacrylonitrile (PAN) carbon fibers and their chemical precursor (the oxidized PAN or oxypan) which has different electrical properties. Fibers are imaged by electron and ion beams and sectioned by the focused ion beam (FIB). A sample of oxypan fibers processed by a radio frequency (RF) plasma is also investigated and the role of the conductive carbon layer around their unmodified, insulating bulk is discussed. A suitable developed edge detection technique (EDT) on electron, ion images, and after the FIB sectioning, provides quantitative information about the thickness of the created layer. © 2007 Wiley Periodicals, Inc.

Nitrogen lasers have been used for many years to make dye solutions lase. A nitrogen laser, which transverse electrical discharge in gas at atmospheric pressure has been built in our laboratory. It has been characterized and applied to pump different dyes: Rhodamine 6G, Coumarin 440, DOTCI, and pyranine in simple "on axis" geometric configuration. It has been shown that pyranine can lase in the absence of any optical external mirror cavity, this happens at very low threshold, and in different solvents. Dyes under consideration can be grouped into two major classes according to their lasing behavior independently on their concentration in the solvent: Rhodamine 6G and DOTCI can lase both axially or transversally and Coumarin 440 and pyranine can lase only axially. Other intriguing features have been observed that span from simultaneous multiple beam generation, to super fluorescence and to distribute axial pumping of dye solutions. A preliminary basis for understanding and controlling such processes is the spatial energy distribution and the energy density of the beam.

Innovative techniques for the acquisition and analysis of delayed luminescence (DL) signals are proposed and discussed. At a preliminary level, the signals prove to be a useful tool, not only for quantitative analysis, but also for discrimination - on theoretical grounds - among different, possibly competing, mechanisms responsible for DL in photosynthetic organisms. Moreover, DL recordings from non-photosynthetic organisms ( S. cerevisiae yeast) with avalanche photodiode (APD) detection will be discussed.

The focused ion beam (FIB) technique of nanomachining combined with simultaneous scanning electron microscopy (SEM) was used for submicron manipulation and imaging of unprepared (fresh) cells to demonstrate the potentiality of the FIB/SEM technique for ultramicroscopic studies. Sectioning at the nanoscale level was successfully performed by means of ion beam-driven milling operations that reveal the ultrastructure of fresh yeast cells. The FIB/SEM has many advantages over other ultramicroscopy techniques already applied for unprepared/fresh biological samples

HMDSO plasma polymer films are known to reduce the resulting surface free energy and the permeation rate of water vapour and oxygen through the treated polymer substrates. In this work, plasma polymer films were deposited from hexamethyldisiloxane (HMDSO) on polyethylene terephthalate surfaces under different operating conditions and the resulting surface properties were investigated. The structure and bondings in the deposited films were studied by means of IR spectroscopy. The thickness of the deposited films was deduced observing images acquired with a focused ion beam (FIB). Hydrophobic performances were investigated by means of water droplet contact angle measurements. Correlation between operating deposition conditions and resulting structure and surface properties of the films were also discussed.

In this paper, a novel technique is presented for the characterization at the nanoscale of plasma-assisted deposit on polyethylene-terephthalate (PET) polymer films. In previous studies, some microcharacterization and morphology analyses of plasma-assisted deposition were performed by atomic force microscopy (AFM). In the work presented here, we analysed the thickness and homogeneity of plasma-assisted deposits by focused ion beam (FIB). This technique with 5-7 nm resolution requires no sample preparation and relies on a sequence of operations on a relatively fast time scale, so that it is easy to make thorough investigations of the sample. We performed electron and ion imaging of the surface of the material, and a subsequent ionic cutting allowed the study of the morphology of the same sample. We developed a novel approach to the edge detection techniques (EDT) in images for a fast evaluation and monitoring of the deposited layer. © FAMS, Inc.

The FIB/SEM system was satisfactorily used for scanning ion (SIM) and scanning electron microscopy (SEM) of gland epithelial cells of a terrestrial isopod Porcellio scaber (Isopoda, Crustacea). The interior of cells was exposed by site-specific in situ focused ion beam (FIB) milling. Scanning ion (SI) imaging was an adequate substitution for scanning electron (SE) imaging when charging rendered SE imaging impossible. No significant differences in resolution between the SI and SE images were observed. The contrast on both the SI and SE images is a topographic. The consequences of SI imaging are, among others, introduction of Ga+ ions on/into the samples and destruction of the imaged surface. These two characteristics of SI imaging can be used advantageously. Introduction of Ga+ ions onto the specimen neutralizes the charge effect in the subsequent SE imaging. In addition, the destructive nature of SI imaging can be used as a tool for the gradual removal of the exposed layer of the imaged surface, uncovering the structures lying beneath. Alternative SEM and SIM in combination with site-specific in situ FIB sample sectioning made it possible to image the submicrometre structures of gland epithelium cells with reproducibility, repeatability and in the same range of magnifications as in transmission electron microscopy (TEM). At the present state of technology, ultrastructural elements imaged by the FIB/SEM system cannot be directly identified by comparison with TEM images.

Living systems cannot be thermal systems, but instead are coherent systems. The dynamic origin of coherence is discussed in the case of electromagnetically coupled particles. Permanent nonvanishing electromagnetic fields are shown to be present but trapped in the coherent systems. The dynamics of enzymes is sketched as an outcome of the coherent electromagnetic structure of living matter. The emergence of bound water is analyzed. Circulation of ions is shown to be driven by the Josephson effect. Ion cyclotron resonance briefly is discussed.

The use of the Soft X-ray Contact Microscopy technique is discussed as a possible new tool to get information on dopant distribution in the core of single-mode optical fibers with 50 nm spatial resolution.

In this paper, we present a novel technique for the nanoscale characterization of the outer and inner structure of tyre debris. Tyre debris is produced by the normal wear of tyres. In previous studies, the microcharacterization and identification were performed by analytical electron microscopy. This study is a development of the characterization of surface and microstructure of tyre debris. For the first time, tyre debris was analysed by focused ion beam (FIB), a technique with 2- to 5-nm resolution that does not require any sample preparation. We studied tyre debris produced in the laboratory. We made electron and ionic imaging of the surface of the material, and after a ionic cut, we studied the internal microstructure of the same sample. The tyre debris was analysed by FIB without any sample preparations unlike the case of scanning and transmission electron microscopy (SEM and TEM). Useful information was derived to improve detection and monitoring techniques of pollution by tyre degradation processes

The possibility of a pressure monitoring system by differential pressure sensors to detect contaminant effects on cellular cultures metabolic activity is discussed using Saccharomyces cerevisiae, lymphocyte, and AHH1 cell cultures. Metabolic (aerobic and anaerobic) processes in cells are accompanied by CO2 production that induces changes in pressure values when cells are cultured in sealed vessels. These values are subsequently converted in voltage units and plotted pressure dynamics versus time. This procedure leads to a standard curve, typical of the cellular line, which characterizes cellular metabolism when all parameters are controlled, such as temperature and nutrients. Different phases appear in the S. cerevisiae differential pressure curve: an initial growth up to a maximum, followed by a decrement that leads to a typical "depression" (pressure values inside the test-tubes are lower than the initial one) after about 35 h from the beginning. The S. cerevisiae differential pressure curve is successfully used to test the effects of chemical (Amuchina(R), trieline) and physical (UV radiation, blue light, magnetic fields) contaminants. The same technique is applied to lymphocytes and AHH1 cultures to investigate the effects generated by a 72-h exposure to a 50-Hz, 60-muT electromagnetic field. Lymphocyte samples, cultured in a PHA medium, grow less than control ones, but exhibit a greater metabolic activity: changes in the exposure system configuration influence neither sample growth differences nor metabolic response variations between control and irradiated samples, while all the other irradiation parameters remain constant. Control and irradiated lymphocyte samples, without PHA in culture medium, show the same behavior both during irradiation and metabolic test. AHH1 control and irradiated samples show no difference both in growth percentage during irradiation and in metabolic activity. Different cell cultures respond to the same stimulus in different manners.

The use of spectrophotometers for the measurement of cell concentration in yeast suspension is critically discussed. Corrections are derived which take into account cell size, shape, cell aggregation (flocculation) and non linear effects related to sample thickness.

The results are discussed of a systematic investigation into the electromagnetic held (EMP) exposure consequences on human lymphocytes. These artificial fields have intensities comparable to the Earth's magnetic field, and are used for exposures up to 4 days. Different and complementary techniques are used to safely assess the consequences of EMFs on the cells; in particular, morphology, metabolism, and population dynamics are investigated. The recourse to ultramicroscopy, pressure monitoring in sealed bottles, atomic mass spectroscopy, and cytofluorimetry techniques give good insight into the EMF-induced changes. A statistically significant deviation of irradiated samples with respect to control samples is reported. A critical analysis and a survey of similar experiments reported in the literature led us to examine the experimental setup with attention to the geometry of the irradiation system. Yeast cells were used as a model system to statistically test the different steps in the overall procedure, thanks to information gathered during a radiobiology experiment performed at the Rutherford Appleton Laboratory. Finally, the role of different magnetic field detectors in the reproducibility of the experiments is carefully discussed.