Showing papers on "Blisters published in 2009"

Surface morphology and deuterium retention in tungsten exposed to low-energy, high flux pure and helium-seeded deuterium plasmas

Abstract: Blistering and deuterium retention in re-crystallized tungsten exposed to low-energy, high flux pure and helium-seeded D plasmas to a fluence of 1027?D?m?2 have been examined with scanning electron microscopy, thermal desorption spectroscopy, and the D(3He,p)4He nuclear reaction at 3He energies varied from 0.69 to 4.0?MeV. In the case of exposure to pure D plasma (38?eV?D?1), blisters with various shapes and sizes depending on the exposure temperature are found on the W surface. No blisters appear at temperatures above 700?K. The deuterium retention increases with the exposure temperature, reaching a maximum value of about 1022?D?m?2 at 480?K, and then decreases as the temperature rises further. Seeding of 76?eV He ions into the D plasma significantly reduces the D retention at elevated temperatures and prevents formation of the blisters.

Skin blister and skin biopsy to quantify epidermal nerves: A comparative study

Abstract: Background: Skin biopsy is an important procedure for the diagnosis of peripheral neuropathy. The main indicators of unmyelinated nerve involvement are decreased density and abnormal morphology of epidermal nerve fibers (ENFs). The suction skin blister is an alternative, less invasive method to visualize and quantify ENFs. The blister roof provides an integrated bird’s eye view of all ENFs within one tissue specimen. Objective: We compared the suction skin blister method to the punch skin biopsy for evaluation of ENFs. Methods: Twenty-five volunteers, 35 to 62 years old, without symptoms or history of peripheral neuropathy, and normal by neurologic examination and nerve conduction tests, were studied. One 3 mm punch biopsy and two 3 mm suction blister specimens were collected from the right foot and calf. Comparison between blister and biopsy ENF density was assessed by repeated measures analysis of covariance, accounting for age, gender, and specimen’s location. Results: The epidermal roof of the suction skin blister permitted detailed analyses of ENF density, morphology, and distribution across the epidermis and observation of ENF branching pattern. No systematic differences of ENF density were found between skin blisters and biopsies ( p = 0.29) or between pairs of blisters from the same location ( p = 0.15). ENF density was lower for older subjects ( p Conclusions: The suction skin blister method has potential as a diagnostic tool to investigate small fiber neuropathies. It is a minimally invasive and reliable technique, comparable to skin biopsy for determining epidermal nerve fiber density. BMI = body mass index; ENF = epidermal nerve fiber; PBS = phosphate buffered saline.

Helium Retention and Desorption Behaviour of Reduced Activation Ferritic/Martenstic Steel

Abstract: The reduced activation ferritic/martenstic steel CLF-1 prepared by the Southwestern Institute of Physics in China was irradiated by helium ions with an energy of 5 keV at room temperature using an electron cyclotron resonance (ECR) ion irradiation apparatus. After the irradiation, the helium retention and desorption were investigated using a technique of thermal desorption spectroscopy (TDS). The experiment was conducted with both the normal and welded samples. Blisters were observed after the helium ion irradiation, and the surface density of blisters in the welded samples was lower than that in the non-welded samples. Three desorption peaks were observed in both the non-welded and welded samples. These desorption peaks corresponded to those of blister ruptures and the helium release from the inner bubbles and the defects. The amount of helium retained in the welded samples was approximately the same as that in the non-welded samples, which was much less than other reduced activation materials, such as vanadium alloy and SiC/SiC composites.

Characterization of surface morphology and retention in tungsten materials exposed to high fluxes of deuterium ions in the tritium plasma experiment

Abstract: Under appropriate conditions, exposing tungsten to a high flux D plasma creates near-surface blisters and other changes in surface morphology. We have characterized the sizes of blisters formed at different temperatures (147 °C≤Tsurface≤704 °C) and performed a surface analysis to elucidate factors that influence blister formation. Tungsten targets that were exposed to low energy (70 eV) D ions at a flux of 1.1×1022 m−2 s−1 in the tritium plasma experiment (TPE) were considered. We used AES to analyze the surface for evidence of implanted impurities. Blister diameters and heights were quantified using SEM imagery and vertical scanning interferometry. Given the likelihood of D precipitation in blisters, we expect that the data obtained here could be incorporated into a computational model to better simulate the diffusion and desorption of D in W. With this in mind, we present an analysis of thermal desorption profiles showing the release of D from the surface.

Sealing apparatus with sealing load control

Abstract: An apparatus for sealing a cover film to a blister film having blisters holding respective small objects has a feed roll rotatable about an axis and formed with an array of radially outwardly open recesses arrayed like the blisters of the blister film. The blister film passes over the feed roll with the blisters in the recesses. A sealing roll is rotatable about an axis generally parallel to the feed-roll axis and presses the cover foil down against the blister foil on the feed roll. The feed roll is rotated to pull the films in a travel direction between the rolls so that the cover film is sealed to the blister film between the blisters thereof. A sensor detects movement of the sealing roll transversely of the feed-roll axis. A controller generates an output when the detected movement exceeds a threshold.

Determination of residual stresses around blisters in Zr-2.5%Nb pressure tubes

Abstract: We have used synchrotron X-ray diffraction experiments to measure the strain field introduced by a hydride blister grown on a section of a pressure tube from a CANDU nuclear reactor. After charging the tube section with a homogeneous hydrogen concentration of 300 wt ppm, the blister was produced by creating a small cold spot on its surface (similar to 200 degrees C), while the bulk was kept at a temperature of 338 degrees C over a period of 1008 h. The blister studied here is ellipsoidal in shape, with its long axis along the tube axial direction. The experiments were performed on the wiggler beam line ID15 at the European Synchrotron Radiation Facility (ESRF) using a polychromatic beam of high-energy X-rays (60 to 300 keV). Unlike conventional X-ray diffraction, in this mode the scattering angle is fixed and the diffracted beam is discriminated on the basis of the photon energy. The results show that the blister is composed by two crystallographic phases (delta-ZrH and alpha-Zr), with volume fractions varying with position. The maximum stresses appear at the blister-matrix interfaces. Near the tube outer surface, we found large compressive stresses of (-450 +/- 90) MPa along the blister long axis, and tensile stresses (+320 +/- 90) MPa along the tube hoop direction. The main uncertainty in these stresses results from the uncertainty in the elastic constants of the hydride phase. Large strains and broad peaks were observed for this phase, which were explained by a rather low Young's modulus (35 GPa) for the hydride. The results are compared with finite element simulations found in the literature. (C) 2009 International Centre for Diffraction Data. [DOI: 10.1154/1.3139056] (Less)

Blister formation in ion-implanted GaAs: Role of diffusivity

Abstract: We have investigated the influence of substrate temperature during implantation, Timplant, on blister formation in GaAs:N layers produced by N ion implantation followed by rapid thermal annealing. Similar depths of popped blisters (craters) and damage profiles were observed for both low and high Timplant. This is in contrast to reports of Timplant-dependent blister formation in higher-diffusivity systems such as GaAs:H and Si:H. The apparent Timplant-insensitivity of blister formation in GaAs:N is likely due to the lower diffusivity of N in GaAs in comparison to that of H in GaAs and Si.

Numerical analysis of the kinetics of propagation of hydrogen blisters in the oil-and-gas equipment

Abstract: We consider a problem of cracking of metals (formation of blisters) in the oil-and-gas equipment. The causes of initiation of the nuclei of hydrogen blisters are investigated and, on this basis, a mathematical model of their growth is developed with regard for the electrolytic hydrogenation of the metal surface, hydrogen diffusion into the metal, and its accumulation in the internal microdefects. We also present an example of analysis of the kinetics of growth of circular blisters in low-carbon and low-alloy steels under the action of hydrogen penetrating into the metal in the process of corrosion in wet hydrogen-sulfide media.

Inhaler and method of coiling blister strips

Abstract: An inhaler includes a housing to receive a strip of blisters each containing a dose of medicament and being sequentially movable into alignment with means for breaching a blister to enable a user to inhale said dose contained therein. The device comprises a segmented spiral element within the housing that receives and coils a strip of blisters, such as the used portion of the blister strip. A method of controlling a strip of blisters within an inhalation device is also disclosed, as well as a method of forming a strip of blisters for insertion into an inhalation device.

Packaging for two different blisters

Abstract: The invention relates to a packaging, comprising a hollow body ( 5 ) extending along a longitudinal axis (A) and a blister carrier ( 6 ) slidably arranged therein for accommodating a blister ( 20 ). The blister carrier ( 6 ) is designed in such a way and blisters are or can be fastened to the blister carrier ( 6 ) in such a way that the blister carrier ( 6 ) can accommodate at least two different blisters ( 20 ), which differ in regard to the quantity and/or arrangement of the pockets. The blister carrier ( 6 ) has a carrier section ( 14 ) that is frame-shaped.

Formation of blisters in thin metal films on lithium niobate implanted by keV Ar+ ions

Abstract: Bubble-like and crater-like blisters were observed at the boundaries of the structures “thin Ni film–lithium niobate” and “thin Pd film–lithium tantalate” implanted by Ar ions. Analyses of these systems by AFM and SEM have shown that ion implantation essentially modifies near-surface structures with changing their optical, electrical and mechanical properties. Differences in the optical properties and surface structure between implanted and non-implanted systems are observed and explained by different properties of materials, widening interface “film–substrate” as well as by other known effects and phenomena. Enhanced adhesion of these films to substrate, nonselective spectral response is a base for effective and perspective application of the systems in development of high-sensitive pyroelectric detectors with a wide spectral range and high optical damage threshold.

Blisters in Diabetes

Abstract: Blisters initially form because the outer layer of the skin has become damaged. Fluid collects under the damaged layer of skin, initially cushioning the tissue underneath, protecting it from further damage and allowing it to heal. When the pressure of the fluid is too great it can create further damage to the underlying tissues. A blood blister usually forms when a small blood vessel close to the surface of the skin ruptures and blood leaks into a tear between the layers of skin. This can happen if the skin is crushed, pinched or squeezed very tightly.1 In the diabetic patient these are often seen in pressure areas.

Blister package producing method for packing pharmaceutical product, involves pressing out product pieces present in false blister, and separately collecting product pieces and pressed out false blister

Abstract: The method involves deep-drawing areas (6) formed for blister packages (2) in a plastic film web (3). The areas are filled with product pieces (34) and closed with a heat sealing film (8), and the blister packages are stamped out from the plastic film web. A false blister (27) formed immediately after a production and separation of good blisters (24), is deblistered at production speed. The product pieces present in the false blister are pressed out, and the product pieces and the pressed out false blister are separately collected. An independent claim is also included for a machine for producing a blister package, comprising a deep-drawing station.