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Across all branches of science, medicine and engineering, high-resolution microscopy is required to understand functionality. Although optical methods have been developed to `defeat' the diffraction limit and produce 3D images, and electrons have proven ever more useful in creating pictures of small objects or thin sections, so far there is no substitute for X-ray microscopy in providing multiscale 3D images of objects with a single instrument and minimal labeling and preparation. A powerful technique proven to continuously access length scales from 10 nm to 10 µm is ptychographic X-ray computed tomography, which, on account of the orthogonality of the tomographic rotation axis to the illuminating beam, still has the limitation of necessitating pillar-shaped samples of small (ca 10 µm) diameter. Large-area planar samples are common in science and engineering, and it is therefore highly desirable to create an X-ray microscope that can examine such samples without the extraction of pillars. Computed laminography, where the axis of rotation is not perpendicular to the illumination direction, solves this problem. This entailed the development of a new instrument, LamNI, dedicated to high-resolution 3D scanning X-ray microscopy via hard X-ray ptychographic laminography. Scanning precision is achieved by a dedicated interferometry scheme and the instrument covers a scan range of 12 mm × 12 mm with a position stability of 2 nm and positioning errors below 5 nm. A new feature of LamNI is a pair of counter-rotating stages carrying the sample and interferometric mirrors, respectively., Journal of Synchrotron Radiation, 27 (3), ISSN:0909-0495, ISSN:1600-5775

Optical methods of super-resolution microscopy, such as confocal microscopy, structured illumination, nonlinear microscopy, and image scanning microscopy are reviewed. These methods avoid strong invasive interaction with a sample, allowing the observation of delicate biological samples. The meaning of resolution and the basic principles and different approaches to superresolution are discussed.

ERNiCrFe-13 was developed based on ERNiCrFe-7A with Nb and Mo addition with the aim of further improving ductility dip cracking. In addition, solidification cracking susceptibility may increase against a wide solidification temperature range due to Nb and Mo segregation. In this study, the solidification behavior of the deposited metal via gas tungsten arc welding (GTAW) with an experimental ERNiCrFe-13 wire was investigated using JMatPro solidification calculations, differential scanning calorimetry (DSC) analysis, in situ observations by laser confocal scanning microscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Both Nb and Mo exhibited segregation toward the liquid phase during solidification, while Fe showed opposite tendency according to the calculated partition coefficients k at the initial solidification stage. The k based on both the solidification calculation and EDS tests showed that Nb had a stronger segregation tendency than Mo. The solidification temperature range (STR) tested by DSC was significantly narrower than the predicted STR, which can be attributed to the overestimated segregation based on the Scheil model. The in-situ observation results showed that the relationship between the liquid phase area fraction f and temperature T followed the Avrami equation well. The solidification process included three stages: initial nucleation stage, rapid growing-up stage, and final solidification stage with rates of 0.015 s−1, 0.15 s−1, and 0.015 s−1, respectively.

Image Scanning Microscopy (ISM) has emerged as a successful and robust technique which nearly doubles the spatial resolution of a confocal microscope by simple means. Meanwhile, it has found implementation into several highly successful commercial systems, and it has branched into different experimental realizations. The review gives a brief introduction into the basic principles of ISM, and it reports about recent progress and applications of this new microscopy technique.

Structured illumination microscopy and image scanning microscopy are two microscopical tech- niques, rapidly increasing in practical application, that can result in improvement in transverse spatial resolution, and/or improvement in axial imaging performance. The history and principles of these techniques are reviewed, and the imaging properties of the two methods compared. This article is part of the Theo Murphy meeting issue ‘Super-resolution structured illumination microscopy (part 1)’.

Many of the most important resolution improvements in optical microscopy techniques are based on the reduction of scattering effects. The main benefit of polarimetry-based imaging to this end is the discrimination between scattering phenomena originating from complex systems and the experimental noise. The determination of the coherency matrix elements from the experimental Mueller matrix can take advantage of scattering measurements to obtain additional information on the structural organization of a sample. We analyze the contrast mechanisms extracted from (a) the coherency matrix elements, (b) its eigenvalues and (c) the indices of polarimetric purity at different stages of zebrafish embryos, based on previous work using Mueller matrix optical scanning microscopy. We show that the use of the coherency matrix and related decompositions leads to an improvement in the imaging contrast, without requiring any complicated algebraic operations or any a priori knowledge of the sample, in contrast to standard polarimetric methods.

Lenses are dominantly popular in various imaging systems, either as objective optics to form images directly or as focusing optics for scanning microscopy. While a lens-based imaging system is elegant and intuitive, the lens also limits achievable image quality. Alternative approaches seek complementary imaging methods without physical image-forming lenses, thus eliminating the associated limitations. Coherent diffractive imaging (CDI) emerged as one of the lensless imaging techniques, which can provide a diffraction-limited resolution with multiple contrasts.

Snowpack exhibits properties that make it a unique natural archive of airborne pollution. The data on insoluble particles in the Ob River catchment (Western Siberia) snowpack are limited. Insoluble particles in the snowpack of Western Siberia were studied at 36 sites on a 2800 km submeridional profile from the city of Barnaul to Salekhard in February 2020. Snow samples were collected over the full depth of the snow core, from the surface of the snow cover to the boundary with soil, except for the lower 1&ndash, 2 cm. After the filtration of melted snow through a 0.45-&micro, m membrane, the particle composition was studied using a scanning electron microscope with an energy microprobe. In the background areas, the concentration of insoluble particles in the snow was below 2 mg/L. Significantly higher particle concentrations were encountered near cities and hydrocarbon production areas. Particulate matter in snow mainly consists of biogenic and lithogenic particles mixed with anthropogenic particles (ash and black carbon aggregates). The proportion of anthropogenic particles increases near cities and areas of active hydrocarbon production.

Fourier transform infrared (FT-IR) spectroscopic imaging and microscopy of single living cells are established label-free technique for the study of cell biology. The constant driver to improve the spatial resolution of the technique is due to the diffraction limit given by infrared (IR) wavelength making subcellular study challenging. Recently, we have reported, with the use of a prototype zinc sulfide (ZnS) transmission cell made of two hemispheres, that the spatial resolution is improved by the factor of the refractive index of ZnS, achieving a λ/2.7 spatial resolution using the synchrotron–IR microscopy with a 36× objective with numerical aperture of 0.5. To refine and to demonstrate that the ZnS hemisphere transmission device can be translated to standard bench-top FT-IR imaging systems, we have, in this work, modified the device to achieve a more precise path length, which has improved the spectral quality of the living cells, and showed for the first time that the device can be applied to study live cells with three different bench-top FT-IR imaging systems. We applied focal plane array (FPA) imaging, linear array, and a synchrotron radiation single-point scanning method and demonstrated that in all cases, subcellular details of individual living cells can be obtained. Results have shown that imaging with the FPA detector can measure the largest area in a given time, while measurements from the scanning methods produced a smoother image. Synchrotron radiation single-point mapping produced the best quality image and has the flexibility to introduce over sampling to produce images of cells with great details, but it is time consuming in scanning mode. In summary, this work has demonstrated that the ZnS hemispheres can be applied in all three spectroscopic approaches to improve the spatial resolution without any modification to the existing microscopes.

Handheld and endoscopic optical-sectioning microscopes are being developed for noninvasive screening and intraoperative consultation. Imaging a large extent of tissue is often desired, but miniature in vivo microscopes tend to suffer from limited fields of view. To extend the imaging field during clinical use, we have developed a real-time video mosaicking method, which allows users to efficiently survey larger areas of tissue. Here, we modified a previous post-processing mosaicking method so that real-time mosaicking is possible at >30 frames/second when using a device that outputs images that are 400 × 400 pixels in size. Unlike other real-time mosaicking methods, our strategy can accommodate image rotations and deformations that often occur during clinical use of a handheld microscope. We perform a feasibility study to demonstrate that the use of real-time mosaicking is necessary to enable efficient sampling of a desired imaging field when using a handheld dual-axis confocal microscope.

For almost a century, the resolution of optical microscopy was thought to be limited by Abbe's law describing the diffraction limit of light. At the turn of the millennium, aided by new technologies and fluorophores, the field of optical microscopy finally surpassed the diffraction barrier: a milestone achievement that has been recognized by the 2014 Nobel Prize in Chemistry. Many super-resolution methods rely on the unique photophysical properties of the fluorophores to improve resolution, posing significant limitations on biological imaging, such as multicoloured staining, live-cell imaging and imaging thick specimens. Structured Illumination Microscopy (SIM) is one branch of super-resolution microscopy that requires no such special properties of the applied fluorophores, making it more versatile than other techniques. Since its introduction in biological imaging, SIM has proven to be a popular tool in the biologist's arsenal for following biological interaction and probing structures of nanometre scale. SIM continues to see much advancement in design and implementation, including the development of Image Scanning Microscopy (ISM), which uses patterned excitation via either predefined arrays or raster-scanned single point-spread functions (PSF). This review aims to give a brief overview of the SIM and ISM processes and subsequent developments in the image reconstruction process. Drawing from this, and incorporating more recent achievements in light shaping (i.e. pattern scanning and super-resolution beam shaping), this study also intends to suggest potential future directions for this ever-expanding field.

The ZEISS LSM-510 laser scanning microscope was modified; as a result, a system for recording digital holograms in the scanning mode of the microscope was obtained. The features of the reconstruction of recorded holograms are considered both theoretically and by simulation. Phase distortion impact is investigated. Algorithm and MatLab code for reconstruction of holograms was created allowing correct restoration both intensity and phase of the object wave. Comments and questions should be directed to the OSA Conference Papers staff (tel: +1 202.416.6191, e-mail: cstech@osa.org).

We reintroduce the concept of SOFISM and discuss its practical aspects. We demonstrate that supplying a confocal microscope with a SPAD array detector enables super-resolution imaging relying on fluorophore blinking within reasonable dwell times.

Synchrotron X-ray Scanning Tunneling Microscopy (SX-STM) is a novel imaging technique capable of providing real space chemically specific mapping with a potential of reaching atomic resolution. Determination of chemical composition along with ultra-high resolution imaging by SX-STM can be realized through excitation of core electrons by incident X-rays when their energy is tuned to an absorption edge of a particular atom during raster scanning, as is done in the conventional STM experiments. In this work, we provide a brief summary and the current status of SX-STM and discuss its applications for material science. In particular, we discuss instrumentation challenges associated with the SX-STM technique and present early experiments on Cu doped ZrTe3 single crystals.

Sprayed fiber-reinforced concrete is used in construction for the execution and repair of reinforced concrete elements. It is believed that the addition of steel fibers is most effective, due to their parameters and low costs. Some researchers, however, suggest that the addition of steel fibers can contribute to the initiation of corrosion of the main reinforcement. In consideration of the differences of opinion on the corrosion resistance of sprayed fiber-reinforced concrete, it has become necessary to analyze this issue. The article presents comparative studies of corrosion assessments of the main reinforcement in specimens made of ordinary concrete and concrete with steel fibers. The tests were performed using a semi non-destructive galvanostatic pulse method, which allows location of the areas of corrosion and estimation of the reinforcement corrosion activity. In order to initiate the corrosion processes the specimens were subjected to freezing cycles in NaCl solution. In addition, the shrinkage and compressive strength of specimens were measured, and the observation of specimen structure under a scanning microscope was performed. It was found that galvanostatic pulse method allowed estimation of the reinforcement corrosion progress. The corrosion of the main reinforcement in steel fiber reinforced concrete specimens was less advanced than in the specimens without fibers.

This paper reports the development of optical fibre scanner using dual-core multi-mode fibre for imaging biological sample. The fibre is driven with non-repeating Lissajous scan pattern. The reconstructed image from a barcode and granule Saccharomyces Cerevisiae is demonstrated.

Understanding how neural circuits process information requires rapid measurements of activity from identified neurons distributed in 3D space. Here we describe an acousto-optic lens two-photon microscope that performs high-speed focusing and line scanning within a volume spanning hundreds of micrometers. We demonstrate its random-access functionality by selectively imaging cerebellar interneurons sparsely distributed in 3D space and by simultaneously recording from the soma, proximal and distal dendrites of neocortical pyramidal cells in awake behaving mice.

The dust size, the interparticle distance and the time scales associated with the particle motion are ideally suited to study the dusty plasmas by optical techniques. Here, we like to review different diagnostic methods (video microscopy, scanning microscopy, holography, stereoscopy) to measure the structure and dynamics of two-dimensional and three-dimensional micro-dust systems. Also, approaches to determine the dust size (distribution) and dust density (distribution) in a nano-dust cloud are presented.

Image scanning microscopy (ISM) can improve the effective spatial resolution of confocal microscopy to its theoretical limit. However, current implementations are not robust or versatile, and are incompatible with fluorescence lifetime imaging (FLIM). We describe an implementation of ISM based on a single-photon detector array that enables super-resolution FLIM and improves multicolor, live-cell and in-depth imaging, thereby paving the way for a massive transition from confocal microscopy to ISM. A single-photon detector array enables robust and versatile image scanning microscopy (ISM) on any confocal microscope. This implementation makes super-resolution FLIM possible and eases a transition from confocal microscopy to ISM.

Image scanning microscopy (ISM) improves the spatial resolution of conventional confocal laser-scanning microscopy (CLSM), but current implementations reduce versatility and restrict its combination with fluorescence spectroscopy techniques, such as fluorescence lifetime. Here, we describe a natural design of ISM based on a fast single-photon detector array, which allows straightforward upgrade of an existing confocal microscope, without compromising any of its functionalities. In contrast to all-optical ISM implementations, our approach provides access to the raw scanned images, opening the way to adaptive reconstruction methods, capable of considering different imaging conditions and distortions. We demonstrate its utility in the context of fluorescence lifetime, deep, multicolor and live-cell imaging. This implementation will pave the way for a transparent and massive transition from conventional CLSM to ISM.confocal microscopy | time-resolved spectroscopy | image scanning microscopy | single-photon detector array

We describe the design and implementation of two-photon lasers scanning stereomicroscopy, which allows viewing dynamic processes in three-dimensional (3D) space stereoscopically in real-time at the speed of 1.4 volumes per second.

A reconstruction algorithm for holographic scanning microscopy should take into account scanning-associated phase shifts. Here we present the stable, not prone to noise, algorithm which does not require additional recording of the object wave intensity.

We explore a new arena of ultrafast microscopy capturing the femtosecond motion of an individual molecule. Entering a novel, single-electron tunneling regime with lightwave-driven scanning tunneling microscopy, we resolve femtosecond vibrations of a single molecule with sub-angstrom precision.

We present a new generation of a scanning MicroSQUID microscope operating in an inverted dilution refrigerator. The MicroSQUIDs have a size of 1.21$ \ \mu$m\textsuperscript{2} and a magnetic flux sensitivity of 120 $\mu\Phi_{0} / \sqrt{\textrm{Hz}}$ and thus a field sensitivity of %$550^{-6} \ \Phi_{0} / \sqrt{\textrm{Hz}}$ 550$ \ \mu \textrm{G}/ \sqrt{\textrm{Hz}}$. The scan range at low temperatures is about 80 $\mu$m and a coarse displacement of 5 mm in x and y direction has been implemented. The MicroSQUID-to-sample distance is regulated using a tuning fork based force detection. A MicroSQUID-to-sample distance of 420 nm has been obtained. The reliable knowledge of this distance is necessary to obtain a trustworthy estimate of the absolute value of the superconducting penetration depth. An outlook will be given on the ongoing direction of development.

The CTOD test was performed on Instron8801 servo hydraulic testing machine according to the GB/T 2358-94 standard at room temperature. Scanning microscopy was used for observation of the fracture surface of the test specimens and compared with general TIG welded joint. The results show that the average CTOD for high frequency TIG welded joints is lower than the average CTOD for TIG welded joints because of the decrease of the plastic portion of CTOD. The fracture characteristic of high frequency TIG welded joints is dendritic crystal fracture.

We have developed an epi-detected multimodal nonlinear optical microscopy platform based on a compact and cost-effective laser source featuring simultaneous acquisition of signals arising from hyperspectral coherent anti-Stokes Raman scattering (CARS), two-photon fluorescence, and second harmonic generation. The laser source is based on an approach using a frequency-doubled distributed Bragg reflector-tapered diode laser to pump a femtosecond Ti:sapphire laser. The operational parameters of the laser source are set to the optimum trade-off between the spectral and temporal requirements for these three modalities, achieving sufficient spectral resolution for CARS in the lipid region. The experimental results on a biological tissue reveal that the combination of the epi-detection scheme and the use of a compact diode-pumped femtosecond solid-state laser in the nonlinear optical microscope is promising for biomedical applications in a clinical environment.

International audience; We report on a fibered high-resolution scanning surface plasmon microscope for long term imaging of living adherent cells. The coupling of a high numerical aperture objective lens and a fibered heterodyne interferometer enhances both the sensitivity and the long term stability of this microscope, allowing for time-lapse recording over several days. The diffraction limit is reached with a radially polarized illumination beam. Adherence and motility of living C2C12 myoblast cells are followed for 50 h, revealing that the dynamics of these cells change after 10 h. This plasmon enhanced evanescent wave microscopy is particularly suited for investigating cell adhesion, since it can not only be performed without staining of the sample but it can also capture in real time the exchange of extracellular matrix elements between the substrate and the cells.

Using the methods of transmission and scanning microscopy, the features of modification of the grain- and heterophase structure of an V–Zr–C alloy are investigated as a function of its thermomechanical processing. It is shown that the use of the proposed process regimes provides the formation of highly refined (to about 5 nm) secondary-phase precipitates uniformly distributed in the bulk of the material, which significantly improves the strength characteristics at room and elevated (800°C) temperatures, while maintaining acceptable process plasticity. The influence of a variety of hardening factors on parameters of mechanical properties of the V–Zr–C alloy is discussed.

An advanced microcolumn is proposed which adopts a modified einzel lens structure. The newly designed einzel lens is composed of four electrodes. The two center electrodes are specially designed electrostatic quadrupole (EQ) einzel lenses having keyhole instead of circular apertures. We constructed the advanced microcolumn with the EQ-einzel lenses, and operated the newly designed microcolumn in single lens mode and double-lens mode. The preliminary results show that the EQ-einzel lens can improve the performance of the micro-column for large sample applications.

In this paper, varying weight percentages of Ni-coated carbon nanotubes (Ni-CNTs) was incorporated into Sn-Ag-Cu (SAC) solder matrix, to form composite solder. Up to 0.05% of Ni-CNTs were successfully incorporated. After that, the electrochemical behavior of Sn-Ag-Cu with varying weight percentages of Ni-coated carbon nanotubes (Ni-CNTs) composite solder were investigated in 0.3% Na2SO4 solution by using potentiodynamic polarization method. Scanning microscopy was used to characterize the samples after the electrochemical tests. It was observed that the corrosion resistance decreased when the content of Ni-CNTs reached a certain level.

[Tb40Fe60(x nm)/Fe49Co49V2(y nm)](subscript N) multilayers were prepared by multitarget magnetron sputtering using a rotary turn-table technique in a stop-and-go mode. The multilayers were investigated using X-ray diffraction, field emission scan electron microscopy and vibrating sample magnetometry. The result shows that the coercive field drops abruptly with increasing number of bilayers, and it remains generally stable when the number of bilayers is 10 or higher. An excellent magnetic softness with a coercivity of 1.0 mT is obtained for x=5 and y=5 after annealing at 250℃. A crystalline state is observed in FeCoV layers before and after annealing by X-ray diffraction.

The microstructure of Cu-37%Zn-2%Mn-1.6%Al-0.7%Fe-0.7%Si (mass fraction)alloy was studied by scan electron microscopy, X-ray and optical microscopy. The α phase ratio and micro-hardness of this alloy after aging treatment were investigated. The results show that three kinds of phases, such as α phase, β phase and hexagonal club-shape Mn5Si3 phase were observed. The needle α phase ratio increases with aging temperature under 420°C and reach peak value 25 percent after aging at 420°C×1h. The α phase ratio begin decreases when the aging temperature over 420°C. The micro-hardness varying with aging temperature is the opposite.

We develop and test a new method for automatic determi- nation of vessel wall diameters from image stacks obtained using two- photon laser scanning microscopy TPLSM on viable arteries in per- fusion flow chambers. To this extent, a new method is proposed for estimating the parameters of a circle describing the inner diameter of the blood vessels. The new method is based on the Hough transform and the observation that three points that are not colinear uniquely define a circle. By only storing the estimated center location, the com- putational and memory costs of the Hough transform can be greatly reduced. We test the algorithm on 20 images and compare the result with a ground-truth established by human volunteers and a standard least-squares technique. With errors of 3 to 5%, the algorithm enables accurate estimation of the vessel diameters from image stacks contain- ing only small parts of the vessel cross section. Combined with TPLSM imaging of anatomical vessel wall properties, potentially, the algo- rithm enables the correlation of structural and functional properties of large intact arteries simultaneously, without requirements for addi- tional experiments. © 2010 Society of Photo-Optical Instrumentation Engineers. DOI: 10.1117/1.3368679

The histological findings in four globes obtained at autopsy from clinically uncomplicated cases with intraocular lens implants, one glass posterior chamber and three anterior chamber lenses consisting of two pupillary fixated and one »in-the-bag» fixated Binkhorst lens, are reported. Minimal changes could be detected in the tissues with which the implants were in contact. Scanning electron microscopy of the cornea in the three anterior chamber implants showed a loss of endothelial cells in the axial region of roughly 30–50%. There was marked vertical disparity in the loss. Scanning microscopy of the implants showed evidence of surface degradation of the nylon loops of all the anterior chamber implants.

Diffractive lenses with overlapping apertures eliminate the strict relations between focal length, lens diameter and pitch of refractive micro-lens arrays.Scanning microscopy is presented as example application benefiting from these new types of lenses.

We describe a fiber-coupled miniature microscope with tunable focus using no mechanical parts for two-photon scanning microscopy in thick mouse brain tissue. A frequency-resolved optical grating (FROG) is used to measure the dispersive effects in the fiber-bundle.

We present a novel recording and reconstruction strategy that allows to obtain label free coherent microscopy of samples flowing in microfluidic channels. Flexible refocusing, custom Field-of-View and magnification are demonstrated.

A new form of tomographic coaxial scanning microscopy is proposed by replacing the standard lens in confocal microscopy with a conical lens (axicon) that generates pencil-like illumination and detection along lines through the object.

A handheld MEMS-scanned line-scanned DAC microscope has recently been developed for oral cancer detection and for guiding brain tumor resections. Additional microscopes are being developed for rapid imaging of freshly excised tissue specimens.

We demonstrate a prototype of a Focused Ion Beam machine based on the ionization of a laser-cooled cesium beam adapted for imaging and modifying different surfaces in the few-tens nanometer range. Efficient atomic ionization is obtained by laser promoting ground-state atoms into a target excited Rydberg state, then field-ionizing them in an electric field gradient. The method allows obtaining ion currents up to 130 pA. Comparison with the standard direct photo-ionization of the atomic beam shows, in our conditions, a 40-times larger ion yield. Preliminary imaging results at ion energies in the 1-5 keV range are obtained with a resolution around 40 nm, in the present version of the prototype. Our ion beam is expected to be extremely monochromatic, with an energy spread of the order of 1 eV, offering great prospects for lithography, imaging and surface analysis., 8 pages, 6 figures

Histochemistry and Cell Biology, 128 (6), ISSN:0948-6143, ISSN:1432-119X

Two-photon excitation laser scanning microscopy has enabled the visualization of deep regions in a biospecimen. However, refractive-index mismatches in the optical path cause spherical aberrations that degrade spatial resolution and the fluorescence signal, especially during observation at deeper regions. Recently, we developed transmissive liquid-crystal devices for correcting spherical aberration without changing the basic design of the optical path in a conventional laser scanning microscope. In this study, the device was inserted in front of the objective lens and supplied with the appropriate voltage according to the observation depth. First, we evaluated the device by observing fluorescent beads in single-and two-photon excitation laser scanning microscopes. Using a 25x water-immersion objective lens with a numerical aperture of 1.1 and a sample with a refractive index of 1.38, the device recovered the spatial resolution and the fluorescence signal degraded within a depth of +/- 0.6 mm. Finally, we implemented the device for observation of a mouse brain slice in a two-photon excitation laser scanning microscope. An optical clearing reagent with a refractive index of 1.42 rendered the fixed mouse brain transparent. The device improved the spatial resolution and the yellow fluorescent protein signal within a depth of 0-0.54 mm.

The phase transformation and sintering behaviors of Ca2P2O7 with different phase composition were investigated by using X-ray powder diffraction (XRD), dilatometery and scan electron microscopy techniques in this paper. It is found that although α-Ca2P2O7 (high-temperature form) could be kept during its cooling process, it is metastable and retransformed into β-Ca2P2O7 (low-temperature form) at about 950 °C during its reheating process. This reversible phase transformation was discussed from the point view of polyhedral distortion. The sample from β-Ca2P2O7 calcined at 1000 °C/2 h densifies much faster than that from α-Ca2P2O7 and α+β mixture, and bulk density as high as 98% TD can be obtained as it is sintered at 1150 °C. A dense α-Ca2P2O7 free of micro-crack could not be obtained whatever from the powder of β-Ca2P2O7 or α-Ca2P2O7 or α+β mixture. Such different sintering behavior was explained in related to the reversible phase transformation between α- and β-Ca2P2O7.

Polyethyleneimine (PEI)-coated slides were used for attachment of unknown extremophiles and their cultures grown at high temperature and low pH. Selective adhesion of cells in natural samples and cultural isolates was compared to polylysine (PL) and several other coatings. PEI is superior to PL for adhesion of extremophiles.

The present paper is concerned with the fatigue behaviour ofcarbon-epoxy laminates with embedded optical fibres subjected to bending loads. The main goal of this investigation was to evaluate quantitatively the effect of the presence of optical fibres within the host structure on its whole fatigue behaviour. Two optical fibre positions were investigated: in the mid-plane of the laminate and near the surface subjected to loading. Two distinct geometries of the ply stacking sequence were also considered, namely unidirectional and crossply. In order to evaluate the fatigue life and the fatigue damage, two different loading levels were used, both at 6 Hz frequency, room temperature and R = 0.1. Fatigue damage was monitored using dynamic stiffness decay and acoustic emission techniques. Failure mechanisms were analysed by means of optical and scanning microscopy. The results obtained lead to the conclusion that the embedding of optical fibres markedly prejudices the fatigue performance of the material ...

The two types of X-ray microscopes, scanning and full-field imaging, have different but complementary capabilities in term of image acquisition and spectroscopies. The novel approach used for the first time in the EU RT&D project Twinmic (HPRI-CT-2001-50024) aims at building of a multipurpose end-station combining scanning and full-field imaging microscopes with easy switch between the two modes. The twin microscope is expected to achieve the state-of-art performance of both microscopy modes in fast imaging, tomography and spectroscopy (μ-XANES/XRF), allowing new class of experiments in exploration of heterogeneous phenomena of the matter at mesoscopic length scales.