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Showing papers on "Blisters published in 2007"


Journal ArticleDOI
TL;DR: In this paper, a step-cascade model was proposed to explain the bursting of deuterium blisters in the near surface region of tungsten exposed to high fluences (up to 1027 D m−2) of high flux (1022D+m−2 s−1).
Abstract: Deuterium retention and blistering in the near-surface region of tungsten exposed to high fluences (up to 1027 D m−2) of high flux (1022D+ m−2 s−1) and low energy (38 eV) deuterium plasma were examined with scanning electron microscopy, focused ion beam and thermal desorption spectroscopy (TDS). Two kinds of blisters appeared at the recrystallized tungsten exposed to the plasma at 520 K. One is the large blisters with sizes of a few tens of micrometres and varying ratios of height against width (up to 0.6), and the other is the small blisters with sizes of less than a few micrometres and a large ratio of height against diameter (about 0.7). A peculiar phenomenon of blister bursting with a tail, or partially opened or fully opened lid was found on some grains after plasma exposure or TDS experiment. In addition, bursting release of deuterium with sudden peaks was observed in the TDS curve below 700 K at a heating rate of 0.5 K s−1. A new model named 'step-cascade model' was proposed to explain the blister bursting. Furthermore, the origin of deuterium retention and blistering as well as future work on high-Z materials were discussed.

181 citations


Journal ArticleDOI
TL;DR: In this paper, the mechanisms of hydrogen retention and blistering in tungsten exposed to high flux deuterium plasmas of tens of eV were studied with a variety of techniques, such as TEM/SEM and TDS.

67 citations


Journal ArticleDOI
TL;DR: The role of pH on the nature and rate of degradation of epoxy coatings on AA2024-T3 panels and subsequent corrosion of the substrate during immersion in NaCl solutions was investigated in this paper.

28 citations


Journal ArticleDOI
TL;DR: This work has shown that computer modeling can be a preferred tool for studying blistering, a common injury in sports and military operations that can adversely effect or even halt performance.
Abstract: Background/purpose: Friction blisters, a common injury in sports and military operations, can adversely effect or even halt performance. Given its frequency and hazardous nature, recent research efforts appear limited. Blistering can be treated as a delamination phenomenon; similar issues in materials science have been extensively investigated in theory and experiment. An obstacle in studying blistering is the difficulty of conducting experiment on humans and animals. Computer modeling thus becomes a preferred tool. Method: This paper used a dynamic non-linear finite-element model with a blister-characterized structure and contact algorithm for outer materials and blister roof to investigate the effects on deformation and stress of an existing blister by changing the friction coefficient and elastic modulus of the material in contact with the blister. Results: Through the dynamics mode and harmonic frequency approach, we demonstrated that the loading frequency leads to dramatic changes of displacement and stress in spite of otherwise similar loading. Our simulations show that an increased friction coefficient does not necessarily result in an increase in either the stress on the hot spot or blister deformation; local maximum friction stress and Von Mises stress exist for some friction coefficients over the wide range examined here. In addition, the stiffness of contact material on blistering is also investigated, and no significant effects on deformation and Von Mises stress are found, again at the range used. The model and method provided here may be useful for evaluating loading environments and contact materials in reducing blistering incidents. Conclusion: The coupling finite-element model can predict the effects of friction coefficient and contacting materials&apos stiffness on blister deformation and hot spot stress.

28 citations


Journal ArticleDOI
TL;DR: In this paper, underfilm corrosion processes were monitored in situ with confocal laser scanning microscopy, showing that pitting at both intermetallic compounds and within the alloy matrix was observed during coating blister formation and growth.
Abstract: Epoxy-coated AA2024-T3 samples were exposed to solutions of specific chloride concentration and pH. Underfilm corrosion processes were monitored in situ with confocal laser scanning microscopy. In near-neutral solutions, pitting at both intermetallic compounds and within the alloy matrix was observed during coating blister formation and growth. Evidence for anodic undermining/corrosion product wedging was obtained. In addition, general corrosion of the matrix led to a strong roughening of the surface. In acidic NaCI solutions, localized corrosion was observed at the original blister site. Thereafter, general attack on the Al-matrix near the original blister was more important than intermetallic particle corrosion. In acidic sulfate solutions, the coating started to fail at many locations on the sample at the same time due to attack of the coating and loss of adhesion at the interface. This more global failure is in agreement with electrochemical impedance measurements and the observation of numerous blisters on large-area panels.

20 citations


Book ChapterDOI
TL;DR: Using a combination of induced skin blistering and collection chambers permits dynamic studies of the aseptic inflammatory reaction in humans to study both cellular functions and pro-/anti-inflammatory mediators that are generated or released.
Abstract: Using a combination of induced skin blistering and collection chambers permits dynamic studies of the aseptic inflammatory reaction in humans. Blisters filled with interstitial fluid can be generated by applying negative pressure to normal skin for up to 2 h. The blisters are subsequently denuded to form superficial "skin windows" that are well defined with regard to area and depth. The denuded areas are covered with a separate collection chamber filled with a suitable medium and left for 18-24 h. During this period, neutrophils and inflammatory agents accumulate in the chamber medium, and sequential events in the inflammatory process can be studied by repeated sampling. Inactive medium or isolated peripheral blood cells from the same individual can be used as controls for both cellular functions and the pro-/anti-inflammatory mediators that are generated or released.

15 citations


Journal ArticleDOI
TL;DR: In this article, the authors performed high-temperature low-strain rate burst tests on irradiated cladding samples with and without hydride lenses or blisters to seek answers to the following questions: Does the presence of a hydrides lens inevitably lead to rupture at a lower pressure? How does it mechanistically affect the crack initiation and propagation?
Abstract: Mechanical response of fuel cladding with local hydride accumulations is crucial in the assessment of cladding integrity at high burn-ups. We have performed high-temperature low-strain rate burst tests on irradiated cladding samples with and without hydride lenses or blisters to seek answers to the following questions: Does the presence of a hydride lens inevitably lead to rupture at a lower pressure? How does it mechanistically affect the crack initiation and propagation? The irradiated samples in our investigation were taken from the regions of the fuel cladding with oxide spallation. Subsequently, we used neutron radiography to further select samples covering a range of hydride blister sizes on which the burst testing was performed. Rupture pressure, hoop strength, and circumferential strain data will be reported. For each sample tested, detailed metallography and fractography were performed on 2-mm size sections containing the burst opening to provide insights into the mechanism of crack initiation and propagation. Local and mean hydrogen concentrations were measured. The paper will include and elucidate new details often not fully investigated by other burst test investigations reported in the open literature. In samples with multiple blisters, the crack initiates at the largest one, which also governs the fracture mode. Reduction in the rupture pressure can be simply correlated to the reduction in sample wall thickness excluding the blister (i.e., its remaining ligament). There is a lower bound on the blister size to have any influence on the rupture pressure. Further, local plastic circumferential strain at each blister can be correlated to relative hydride lens area, as projected onto the cladding surface.

14 citations


Patent
22 Jan 2007
TL;DR: In this article, a child resistant blister pack for packing pharmaceutical solid dosage form comprising a blister sheet having a pattern of cavities/blisters, a rupturable cover foil laminated to the blister sheet covering and sealing the blisters and blister sheet containing the unit dosage forms is enfolded into a non-tearable paper/laminate card with an intrinsic pressure sensitive permanent acrylic/rubber based adhesive.
Abstract: The present invention provides a child resistant blister pack for packing pharmaceutical solid dosage form comprising a blister sheet having a pattern of cavities/blisters, a rupturable cover foil laminated to the blister sheet covering and sealing the blisters and blister sheet containing the unit dosage forms is enfolded into a non-tearable paper/laminate card with an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive, a polymeric film/laminate containing an intrinsic pressure-sensitive permanent acrylic/rubber based adhesive is placed on a non-tearable paper/laminate card in a precise manner, such that it corresponds with the individual cavities of the blister.

14 citations


Journal ArticleDOI
TL;DR: In this article, the behavior of a preheated tungsten target under repetitive pulsed plasma impacts of the energy density 0.75 MJ m−2 with the pulse duration of 0.25 ms was studied with the quasi-stationary plasma accelerator (QSPA) Kh-50.
Abstract: The behaviour of a preheated tungsten target under repetitive pulsed plasma impacts of the energy density 0.75 MJ m−2 with the pulse duration of 0.25 ms was studied with the quasi-stationary plasma accelerator (QSPA) Kh-50. Two identical samples of pure sintered tungsten have been exposed to numbers of pulses exceeding 100. One sample was maintained at room temperature and the other sample preheated at 650 °C. The experiments demonstrated that on the cold surface some macro-cracks dominate, but on the hot surface they do not develop. However, in both cases some fine meshes of micro-cracks are observed. With increasing the number of exposures, the width of the micro-cracks gradually increases, achieving 0.8–1.5 μm after 100 pulses. In addition, the SEM shows some cellular structure with the cell sizes about 0.3 μm, and after large numbers of exposures some blisters of sizes up to 100–150 μm appear.

12 citations


Journal ArticleDOI
TL;DR: In this article, the effects of solute atoms on microstructural evolution and blister formation have been investigated using Ni alloys under 25kV He + and 20kV D + irradiation.

7 citations



Journal ArticleDOI
TL;DR: A 24-year-old man with a 3-year history of severe pruritus affecting the pretibial areas presented with erythematous/violaceous keratotic and crusting lesions with paucity of blisters on the lower limbs and his father and brother presented with extremely disfiguring and strikingly linear raised lesions that had occurred during the past 40 years.
Abstract: A 24-year-old man (patient 1) with a 3-year history of severe pruritus affecting the pretibial areas presented with erythematous/violaceous keratotic and crusting lesions with paucity of blisters on the lower limbs. The blisters appeared after mild trauma and healed as severely pruritic papules. The frequency of new lesions had increased in recent years. The patient’s 50-year-old father and his 45-year-old brother (patients 2 and 3) presented with extremely disfiguring and strikingly linear raised lesions that had occurred during the past 40 years. Severe pruritus and occasional blisters were associated. With age, the occurrence of new blisters reduced, but the pruritic lesions persisted and increased. Lesions initially developed on the extensor aspects of the lower limbs, extending to involve the complete surface of both arms and legs (Fig. 1). All three patients presented rudimentary and dystrophic finger nails and there were no mucosal or milialike lesions. Systemic examination was unremarkable. No other family members were affected and there was no consanguinity. Serum levels of IgE, thyroid hormones and ferritin, and routine blood and urine examinations were normal.

Journal ArticleDOI
TL;DR: Local exfoliation of the oxidized blistered surface allowed surface patterned of both the bare and oxidized surfaces; that is, the patterning of both Si and Si oxide.
Abstract: The exfoliation of surface blisters was investigated as a candidate for a novel surface patterning method. Surface blisters were prepared by H ion implantation into a Si(100) surface. After blister formation, the surface was oxidized. The oxidized blistered surface was irradiated using a focused electron beam. Electron irradiation for 10 min. at an insident energy of 5 keV caused the exfoliation of the blisters. Local exfoliation of the oxidized blistered surface allowed surface patterning of both the bare and oxidized surfaces; that is, the patterning of both Si and Si oxide. This technique thus makes it possible to fabricate surface patterns.

Journal Article
TL;DR: There are high concent of DC in the blister, which is differential and induce the secretion of Th1, the activation of T cell, which modulate the biological response of patients and is helpful for treatment with infective disease.
Abstract: OBJECTIVE Cantharidimide cause blister. The effect of blister on immunoregulation was investigated. METHODS Cantharidimide was placed on the skin, 48h later, the blister was analyzed by flow cytometry. RESULTS The blister contained 1 x 10(6) - 1 x 10(7) cells per ml, most of which were neutrophils, macrophages, dendritic cells (DC), and IL-12 secreted by Thl cells. CONCLUSION There are high concent of DC in the blister, which is differential and induce the secretion of Th1, the activation of T cell. The blister modulate the biological response of patients and is helpful for treatment with infective disease.

Journal Article
TL;DR: In this article, the behavior of epoxy aluminum coating immersed in 3.5 % NaCl solution was investigated using electrochemical impedance spectroscopy (EIS) using SEM and EDX, and the failure mechanism of coating was discussed as well.
Abstract: Electrochemical corrosion behavior of epoxy aluminum coating immersed in 3.5 %NaCl solution was investigated using electrochemical impedance spectroscopy(EIS). SEM and EDX were also used to analyze the surface and cross section images of coating, and the failure mechanism of coating was discussed as well. The experimental results showed that corrosive species can penetrate into coatings and reach the coating/substrate interface promptly, causing the decrease of electro-resistance and the beginning of electrochemical corrosion at the coatings/metal interface. The coating was compact and continuous, while the blisters and cavities occured after corrosion. Blisters were formed by volume expansion of corrosion products, which are mainly oxides and chlorides of Fe and Al, and osmotic pressure created by corrosion species penetration.

Patent
26 Apr 2007
TL;DR: In this paper, a feeder for transferring tablets or capsules supplied in bulk into blisters in a moving strip of plastic sheet comprises a vertical feed unit and a horizontal base plate with recesses in the same pattern as the blisters.
Abstract: The feeder for transferring tablets or capsules supplied in bulk into blisters (5) in a moving strip of plastic sheet (6) comprises a vertical feed unit and a horizontal base plate (3) with recesses (2) in the same pattern as the blisters. The base plate can be moved from a position below the feed unit to a transfer position where a swiveling transfer plate (1, 8) feeds the tablets into the blisters.

Patent
12 Sep 2007
TL;DR: In this paper, the authors disclosed a blister pack comprising a blister assembly (10) including two blister parts (11, 12) which are interconnected and foldable towards each other, each blister part having a set of blisters (16).
Abstract: In the present invention, there is disclosed a blister pack comprising a blister assembly (10) including two blister parts (11, 12) which are interconnected and foldable towards each other, each blister part (11, 12) having a set of blisters (16). The blisters (16) of one blister part (11) are so offset relative to the blisters (16) of the other blister part (12) that, after folding, the blisters (16) of the two blister parts (11, 12) engage between each other. The blister pack further comprises a protective unit (20) including two closure panels (21, 22) and preferably one intermediate panel (23), which is defined by two folding lines (24, 25). The blister pack also comprises a supporting unit (30) including at least one base panel (31), which has at least one hole (33). The supporting unit (30) is connected to said blister assembly (10) such that the blisters (16) of at least one blister part (11) are aligned with said at least one hole (33). The protective unit (20) includes a tab (26; 26'), which is connected to one closure panel (21) via at least one folding line (27; 27'). The supporting unit (30) is fixedly joined to said tab (26; 26') such that the closure panels (21, 22) cover said lid foils after folding of the blister assembly (10) and the protective unit (20). The invention also relates to a process for producing the above-described blister pack.

Journal ArticleDOI
TL;DR: In this paper, Czochralski germanium (Cz Ge) wafers were implanted with hydrogen at energies up to 100 keV (related to H ) at a doses of D = 4•1016 H+/cm2.
Abstract: (100)-oriented Czochralski germanium (Cz Ge) wafers were implanted with hydrogen at energies up to 100 keV (related to H ) at a doses of D = 4•1016 H+/cm2. Post-hydrogen annealing in normal air atmosphere on a hotplate was employed for 10 min at various temperatures between 350 °C and 600 °C to investigate the samples with regard to blistering and layer exfoliation having in mind the Smart-CutTM technology for GOI structure formation. The generation and evolution of blisters and craters (“exploded” blisters demonstrating layer exfoliation) were investigated in dependence on the annealing temperature by atomic force microscopy and µ-Raman spectros-copy. The latter method points out the appearance of strong tensile stress upon H+ implantation and subsequent annealing. If the tensile stress exceeds about 1.2 GPa layer exfoliation occurs.