WorldWideScience

Sample records for swelling materials

  1. Swelling

    Science.gov (United States)

    Except in emergency situations (heart failure or pulmonary edema ), your provider will take your medical history and will perform a physical examination . You may be asked about the symptoms of your swelling. ...

  2. Influence of seawater on swelling characteristics of bentonite buffer material

    International Nuclear Information System (INIS)

    Naoi, Yutaka; Komine, Hideo; Yasuhara, Kazuya; Murakami, Satoshi; Momose, Kazuo; Sakagami, Takeharu

    2005-01-01

    A high level radioactive waste disposal facility may be built on a coastal area. Therefore, it is important to investigate the influence of seawater on bentonite buffer material. The purpose of this study is to investigate the influence of seawater on the swelling pressure and swelling deformation characteristics of five typical kinds of bentonites. This experimental work clarified the relations between the influence grade of seawater and compaction density, type of exchangeable-cation, montmorillonite content of the bentonite, and vertical pressure condition. Based on experimental results, a specification for the buffer material which can overcome the influence of seawater was defined. (author)

  3. Pore-scale Modelling of Capillarity in Swelling Granular Materials

    Science.gov (United States)

    Hassanizadeh, S. M.; Sweijen, T.; Nikooee, E.; Chareyre, B.

    2015-12-01

    Capillarity in granular porous media is a common and important phenomenon in earth materials and industrial products, and therefore has been studied extensively. To model capillarity in granular porous media, one needs to go beyond current models which simulate either two-phase flow in porous media or mechanical behaviour in granular media. Current pore-scale models for two-phase flow such as pore-network models are tailored for rigid pore-skeletons, even though in many applications, namely hydro-mechanical coupling in soils, printing, and hygienic products, the porous structure does change during two-phase flow. On the other hand, models such as Discrete Element Method (DEM), which simulate the deformable porous media, have mostly been employed for dry or saturated granular media. Here, the effects of porosity change and swelling on the retention properties was studied, for swelling granular materials. A pore-unit model that was capable to construct the capillary pressure - saturation curve was coupled to DEM. Such that the capillary pressure - saturation curve could be constructed for varying porosities and amounts of absorbed water. The study material was super absorbent polymer particles, which are capable to absorb water 10's to 200 times their initial weight. We have simulated quasi-static primary imbibition for different porosities and amounts of absorbed water. The results reveal a 3 dimensional surface between capillary pressure, saturation, and porosity, which can be normalized by means of the entry pressure and the effective water saturation to a unique curve.

  4. A grain-scale study of unsaturated flow in highly swelling granular materials

    NARCIS (Netherlands)

    Sweijen, Thomas|info:eu-repo/dai/nl/369415191

    2017-01-01

    Unsaturated flow in swelling porous materials are common and important phenomena in industrial products and earth materials; for example, in paper, hygienic products, swelling clays, and foods. Swelling causes porous media to expand and to deform, which results in a change in pore structure and thus

  5. Simulation of high fluence swelling behavior in technological materials

    International Nuclear Information System (INIS)

    Garner, F.A.; Powell, R.W.; Diamond, S.; Lauritzen, T.; Rowcliffe, A.F.; Sprague, J.A.; Keefer, D.

    1977-06-01

    The U.S. Breeder Reactor Program is employing charged particle irradiation experiments at accelerated displacement rates to simulate neutron-induced microstructural changes in materials of technological interest. Applications of the simulation technique range from the study of fundamental microstructural mechanisms to the development of predictions of the high fluence swelling behavior of candidate alloys for breeder reactor ducts and fuel cladding. An exact equivalence probably cannot be established between all facets of the microstructural evolution which occurs in the disparate charged-particle and neutron environments. To aid in the correlation of data developed in the two environments an assessment has been made of the factors influencing the simulation process. A series of intercorrelation programs and analysis activities have been conducted to identify and explore the relevant phenomena. The factors found to exert substantial influence on the correlation process fall into two categories, one which deals with those variables which are atypical of the neutron environment and one which deals with the additional factors which arise due to the large differences in displacement rate of the two irradiation environments. While the various simulation techniques have been invaluable in determining the basic mechanisms and parametric dependencies of swelling, the potential of these tools in the confident prediction of swelling at high neutron fluence has yet to be realized. The basic problem lies in the inability of the simulation technique to reproduce the early microstructural development in the period that precedes and encompasses the incubation of voids. The concepts of temperature shift and dose equivalency have also been found to be more complicated than previously imagined. Preconditioning of metals in a neutron environment prior to simulation testing is now being employed in order to provide more appropriate starting microstructures

  6. Void migration, coalescence and swelling in fusion materials

    International Nuclear Information System (INIS)

    Cottrell, G.A.

    2003-01-01

    A recent analysis of the migration of voids and bubbles, produced in neutron irradiated fusion materials, is outlined. The migration, brought about by thermal hopping of atoms on the surface of a void, is normally a random Brownian motion but, in a temperature gradient, can be slightly biassed up the gradient. Two effects of such migrations are the transport of voids and trapped transmutation helium atoms to grain boundaries, where embrittlement may result; and the coalescence of migrating voids, which reduces the number of non-dislocation sites available for the capture of knock-on point defects and thereby enables the dislocation bias process to maintain void swelling. A selection of candidate fusion power plant armour and structural metals have been analysed. The metals most resistant to void migration and its effects are tungsten and molybdenum. Steel and beryllium are least so and vanadium is intermediate

  7. Swelling pressures of a potential buffer material for high-level waste repository

    International Nuclear Information System (INIS)

    Lee, Jae Owan; Cho, Won Jin; Chun, Kwan Sik

    1999-01-01

    The swelling pressure of a potential buffer material was measured and the effect of dry density, bentonite content and initial water content on the swelling pressure was investigated to provide the information for the selection of buffer material in a high-level waste repository. Swelling tests were carried out according to Box-Behnken's experimental design. Measured swelling pressures were in the wide range of 0.7 Kg/cm 2 to 190.2 Kg/cm 2 under given experimental conditions. Based upon the experimental data, a 3-factor polynomial swelling model was suggested to analyze the effect of dry density, bentonite content and initial water content on the swelling pressure. The swelling pressure increased with an increase in the dry density and bentonite content, while it decreased with increasing the initial water content and, beyond about 12 wt.% of the initial water content, levelled to nearly constant value. (author). 21 refs., 10 figs., 4 tabs

  8. Comparison of swelling for structural materials on neutron and ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Loomis, B.A.

    1986-03-01

    The swelling of V-base alloys, Type 316 stainless steel, Fe-25Ni-15Cr alloys, ferritic steels, Cu, Ni, Nb-1% Zr, and Mo on neutron irradiation is compared with the swelling for these materials on ion irradiation. The results of this comparison show that utilization of the ion-irradiation technique provides for a discriminative assessment of the potential for swelling of candidate materials for fusion reactors.

  9. Grain-scale modelling of swelling granular materials; application to super absorbent polymers

    NARCIS (Netherlands)

    Sweijen, T.; Chareyre, B.; Hassanizadeh, S.M.; Karadimitriou, N.K.

    Swelling is an important process in many natural materials and industrial products, such as swelling clays, paper, and Super Absorbent Polymer (SAP) particles in hygienic products. SAP particles are capable to absorb large amounts of fluid. Each grain of SAP can absorb water 30 to 1000 times its

  10. Investigation of Pre- and Post-Swelling Behavior of Elastomeric Material

    Directory of Open Access Journals (Sweden)

    M Akhtar

    2013-06-01

    Full Text Available In the last ten years, a new type of modern polymer, known as swelling elastomer, has been used extensively as a sealing element in the oil and gas industry. These elastomers have been instrumental in various new applications such as water shut off, zonal isolation, and sidetracking. Though swell packers can significantly reduce costs and increase productivity, their failure can lead to serious losses. The integrity and reliability of swelling elastomer seals under different field conditions is a major concern. The investigation of changes in material behavior over a specified swelling period is a necessary first step for performance evaluation of elastomer seals. The current study is based on experimental analysis of changes in geometric and mechanical behavior (hardness, tensile, compressive, bulk of an elastomeric material due to swelling. Tests were carried out before and after various stages of swelling. Specimens were placed in saline water (0.6% and 12% concentrations at a temperature of 50°C, with the total swelling period being one month. Swelling, hardness, compression, and bulk tests were conducted using disc samples, while ring samples were used for tensile experiments. A small test rig was designed and constructed for determination of bulk modulus. Stress-strain curves under tension and compression, and pressure volumetric-strain curves were obtained for specimens subjected to different swelling periods. Due to the fast-swell nature of the elastomer, there were sharp changes in mechanical properties within the first few days of swelling for both salinities. Elastic modulus derived from tensile and compressive tests showed a 90% decrease in the first few days. Bulk modulus showed fluctuation in its variation with an increasing swelling period. There was a small effect of salinity only during the first 5 or 6 days.

  11. Swelling, stiffness, and stress in gel material - as related to moisture sorption

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    1996-01-01

    A method is presented by which estimates can be made on swelling, bulk modulus, and internal stresses in gel materials as related to water sorption. Porous gel materials are considered as gel materials made porous by capillary pores large enough not to create capillary condensation and capillary...

  12. Measurement of water transfer and swelling stress in the buffer material due to temperature gradient

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, H. [ITC, Tokai, Ibaraki (Japan); Chijimatsu, M.; Fujita, A.

    1999-03-01

    Coefficients concerning the water transfer in the buffer material was obtained by empirically giving a temperature gradient, and the swelling stress was measured when water was soaked in the sample under the uniform temperature and temperature gradient conditions. The distributions of temperature and water in the buffer material empirically given a temperature gradient were measured to deduce water diffusion constant due to the temperature gradient. The diffusion constant was the order of 10{sup -8} cm{sup 2}/s/degC. As a result of a equitemperature soaking test, it was found that the swelling stress of the part where soaktion was slow was greater than that of the part with fast soaking at a stage of non-uniform water distribution. The water soaking quantity to the sample and swelling stress reached a stationary state after 7000 hours and the water distribution in the whole sample was found saturated. (H. Baba)

  13. Effect of grain size on void swelling in irradiated materials: A phase-field approach

    International Nuclear Information System (INIS)

    Chang, Kunok; Lee, Gyeonggeun; Kwon, Junhyun

    2014-01-01

    The progress of swelling is retarded as the average grain diameter increases in a pure copper case. Within the framework of the production bias model (PBM), their experimental results were quantitatively explained. The phase-field method has already been used to investigate the void/bubble behavior in the irradiated materials. In particular, Millett et al. already incorporated the interaction between the point defect and the grain boundary in their study. Therefore, they described the void denuded zones and void peaked zones adjacent to the grain boundaries, which are already observed in the experimental investigations. We performed the phase-field simulation in order to verify the role of the grain diameter on the void swelling in the cascade damage condition. In addition, our results will be compared with the experimental observations or the theoretical works, such as PBM. Two-dimensional phase-field simulations were performed to investigate the void swelling process in the irradiated materials. We clearly observed the void denuded and void peaked zones, which were already observed in formal experimental and computational approaches. We also found that the progress of swelling was retarded as the average grain diameter increased. The triple junctions, which are believed to be a critical factor t affecting the fracture, are the main cites for the void nucleation and growth in our simulations

  14. Research on swelling clays and bitumen as sealing materials for radioactive waste repositories

    International Nuclear Information System (INIS)

    Allison, J.A.; Wilson, J.; Mawditt, J.M.; Hurt, J.C.

    1991-01-01

    This report describes a programme of research to investigate the performance of composite seals incorporating adjacent blocks of swelling clay and bitumen. It is shown that the interaction of the materials can promote a self-sealing mechanism which prevents water penetration, even when defects are present in the bitumen layer. A review of the swelling properties of highly compacted bentonite and magnesium oxide is presented, and the characteristic sealing properties of bituminous materials are described. On the basis of this review, it is concluded that bentonite is the preferred candidate material for use in composite clay/bitumen seals for intermediate-level radioactive waste repositories. However, it is thought that magnesium oxide may have other sealing applications for high-level waste repositories. A programme of laboratory experiments is described in which relevant swelling and intrusion properties of highly compacted bentonite blocks and the annealing characteristics of oxidised and hard-grade industrial bitumens are examined. The results of composite sealing experiments involving different water penetration routes are reported, and factors governing the mechanism of self-sealing are described. The validation of the sealing concept at a laboratory scale indicates that composite bentonite/bitumen seals could form highly effective barriers for the containment of radioactive wastes. Accordingly, recommendations are made concerning the development of the research, including the implementation of full-scale demonstration experiments to simulate conditions in an underground repository. 13 tabs., 41 figs., 62 refs

  15. Thermal stability, swelling behavior and CO 2 absorption properties of Nanoscale Ionic Materials (NIMs)

    KAUST Repository

    Andrew Lin, Kun-Yi

    2014-11-11

    © The Royal Society of Chemistry 2015. Nanoscale Ionic Materials (NIMs) consist of a nanoscale core, a corona of charged brushes tethered on the surface of the core, and a canopy of the oppositely charged species linked to the corona. Unlike conventional polymeric nanocomposites, NIMs can display liquid-like behavior in the absence of solvents, have a negligible vapor pressure and exhibit unique solvation properties. These features enable NIMs to be a promising CO2 capture material. To optimize NIMs for CO2 capture, their structure-property relationships were examined by investigating the roles of the canopy and the core in their thermal stability, and thermally- and CO2-induced swelling behaviors. NIMs with different canopy sizes and core fractions were synthesized and their thermal stability as well as thermally- and CO2-induced swelling behaviors were determined using thermogravimetry, and ATR FT-IR and Raman spectroscopies. It was found that the ionic bonds between the canopy and the corona, as well as covalent bonds between the corona and the core significantly improved the thermal stability compared to pure polymer and polymer/nanofiller mixtures. A smaller canopy size and a larger core fraction led to a greater enhancement in thermal stability. This thermal stability enhancement was responsible for the long-term thermal stability of NIMs over 100 temperature swing cycles. Owing to their ordered structure, NIMs swelled less when heated or when they adsorbed CO2 compared to their corresponding polymers. This journal is

  16. Gigantic swelling of inorganic layered materials: a bridge to molecularly thin two-dimensional nanosheets.

    Science.gov (United States)

    Geng, Fengxia; Ma, Renzhi; Ebina, Yasuo; Yamauchi, Yusuke; Miyamoto, Nobuyoshi; Sasaki, Takayoshi

    2014-04-09

    Platy microcrystals of a typical layered material, protonated titanate, have been shown to undergo an enormous degree of swelling in aqueous solutions of various amines, including tertiary amines, quaternary ammonium hydroxides, and primary amines. Introducing these solutions expanded the crystal gallery height by up to ~100-fold. Through systematic analysis, we determined that ammonium ion intercalation is predominantly affected by the acid-base equilibrium and that the degree of swelling or inflow of H2O is controlled by the osmotic pressure balance between the gallery and the solution environment, both of which are relatively independent of electrolyte identity but substantially dependent on molarity. In solutions of tertiary amines and quaternary ammonium hydroxides, the uptake of ammonium ions increases nearly linearly with increasing external concentration before reaching a saturation plateau, i.e., ~40% relative to the cation-exchange capacity of the crystals used. The only exception is tetrabutylammonium ions, which yield a lower saturation value, ~30%, owing to steric effects. The swelling behaviors in some primary amine solutions differ as a result of the effect of attractive forces between amine solute molecules on the solution osmotic pressure. Although the swelling is essentially colligative in nature, the stability of the resultant swollen structure is heavily dependent on the chemical nature of the guest ions. Intercalated ions of higher polarity and smaller size help stabilize the swollen structure, whereas ions of lower polarity and larger size lead readily to exfoliation. The insight gained from this study sheds new light on both the incorporation of guest molecules into a gallery of layered structures in general and the exfoliation of materials into elementary single-layer nanosheets.

  17. The phenomena of swelling and growth-expansion during the vitrification of MTR type waste material

    International Nuclear Information System (INIS)

    Facchint, A.; Nannicini, R.; Serrini, G.; Zamorani, E.

    1991-01-01

    A study has been carried out on the foaming effect which occurs during the calcination of MTR type waste materials, in order to improve the in-pot vitrification technology. Foaming is accompanied by swelling and growth-expansion phenomena, and is influenced by the initial composition of the waste and by the operating parameters in the applied vitrification process (in particular the heating conditions). The waste studied is made of a mixture of alkaline sludges and zeolites coming from the treatment of simulated high aluminum content nitric liquid waste (the so-called 'alkaline declassification' process), and the vitrifying additives. During the heat treatment of the samples, attention has been focused on: - softening temperature, - thermal decomposition, examined by differential thermogravimetric analysis, - residual nitrate ion and released gas composition, - iron oxidation state after heat treatment in air and in nitrogen. The foaming effect on the calcined material occurred in the temperature range 923/1023 K and it is due to gas release at temperatures higher than the softening temperature of the calcined material. The most effective remedy in minimizing foaming was found to be the addition of organic substances, such as sugar to the material to be calcined. A weight ratio between sugar and the nitrate content of 1.5 : 1 was found to be sufficient to eliminate the foaming effect. During the waste heating process in presence of sugar, nitrates are totally destroyed at temperatures much lower than the bulk softening point of the material. In addition, within 1273 K in nitrogen, only a partial reduction of iron occurs. (author)

  18. Surface wave propagation in a swelling porous elastic material under a inviscid liquid layer

    Directory of Open Access Journals (Sweden)

    Kuldeep Kumar

    2010-12-01

    Full Text Available The present investigation is to study the surface wave propagationin a swelling porous elastic half space under homogeneous inviscidliquid layer. The frequency equation is derive for both swellingporous (SP and without swelling porous (elastic medium (EL medium. The dispersion curves giving the phase velocity and attenuation coefficient with wave number are plotted graphically to depict the effect of swelling porous half space under a homogeneous inviscid liquid layer. The amplitudes of displacement in both SP and EL medium are obtained and are shown graphically. Some special cases are also deduced from the present investigation.

  19. A formula for determination of swelling characteristics of buffer material containing bentonite and evaluation of self-sealing performance

    International Nuclear Information System (INIS)

    Komine, Hideo; Ogata, Nobuhide

    1998-01-01

    High level radioactive waste disposal facility is planned to construct in a rock board deeper than some hundreds meter at underground, it is necessary to develop a material to refill the gap between waste container and its circumferential rock board. For this material it is required to have high water sealing and swellability, and bentonite is expected to use such application. Production of soil buffer materials containing bentonite is difficult to obtain required dry density by solidifying due to in situ roll-pressing, so it is, at present, thought to be an effective method to carry a block produced in a factory to a pit for disposal to settle. When supposing to produce and settle such buffer material, a gap forming between the buffer material and circumferential rock board or waste container has a large possibility to make a water path when remaining without treating it. Therefore, the buffer material is required to have a function to fill gap portion by swelling deformation and to proof water. In this study, in order to evaluated self-sealing of bentonite, due to a theoretical examination and a laboratory experiment on swelling behavior of soil materials containing bentonite, a swelling evaluation equation of the buffer materials was proposed. And, an application example for outlined design of an actual high level radioactive waste disposal facility was introduced. (G.K.)

  20. Self-sealing cementitious materials by using water-swelling rubber particles

    NARCIS (Netherlands)

    Lv, Leyang; Schlangen, H.E.J.G.; Xing, Feng

    2017-01-01

    Water ingress into cracked concrete structures is a serious problem, as it can cause leakage and reinforcement corrosion and thus reduce functionality and safety of the structures. In this study, the application of water-swelling rubber particles for providing the cracked concrete a self-sealing

  1. Thermal expansion and swelling of cured epoxy resin used in graphite/epoxy composite materials

    Science.gov (United States)

    Adamson, M. J.

    1980-01-01

    The paper presents results of experiments in which the thermal expansion and swelling behavior of an epoxy resin system and two graphite/epoxy composite systems exposed to water were measured. It was found that the cured epoxy resin swells by an amount slightly less than the volume of the absorbed water and that the swelling efficiency of the water varies with the moisture content of the polymer. Additionally, the thermal expansion of cured epoxy resin that is saturated with water is observed to be more than twice that of dry resin. Results also indicate that cured resin that is saturated with 7.1% water at 95 C will rapidly increase in moisture content to 8.5% when placed in 1 C water. The mechanism for this phenomenon, termed reverse thermal effect, is described in terms of a slightly modified free-volume theory in conjunction with the theory of polar molecule interaction. Nearly identical behavior was observed in two graphite/epoxy composite systems, thus establishing that this behavior may be common to all cured epoxy resins.

  2. Micelle swelling agent derived cavities for increasing hydrophobic organic compound removal efficiency by mesoporous micelle@silica hybrid materials

    KAUST Repository

    Shi, Yifeng

    2012-06-01

    Mesoporous micelle@silica hybrid materials with 2D hexagonal mesostructures were synthesized as reusable sorbents for hydrophobic organic compounds (HOCs) removal by a facile one-step aqueous solution synthesis using 3-(trimethoxysily)propyl-octadecyldimethyl-ammonium chloride (TPODAC) as a structure directing agent. The mesopores were generated by adding micelle swelling agent, 1,3,5-trimethyl benzene, during the synthesis and removing it afterward, which was demonstrated to greatly increase the HOC removal efficiency. In this material, TPODAC surfactant is directly anchored on the pore surface of mesoporous silica via SiOSi covalent bond after the synthesis due to its reactive Si(OCH 3) 3 head group, and thus makes the synthesized materials can be easily regenerated for reuse. The obtained materials show great potential in water treatment as pollutants sorbents. © 2011 Elsevier Inc. All rights reserved.

  3. Leg Swelling

    Science.gov (United States)

    ... ed. New York, N.Y.: The McGraw Hill Companies; 2016. http://www.accessmedicine.com. Accessed Dec. 31, ... http://www.mayoclinic.org/symptoms/leg-swelling/basics/definition/SYM-20050910 . Mayo Clinic Footer Legal Conditions and ...

  4. Research on swelling clays and bitumen as sealing materials for radioactive waste repositories

    International Nuclear Information System (INIS)

    Allison, J.A.; Wilson, J.; Mawditt, J.M.; Hurt, J.C.

    1990-10-01

    This report describes a programme of research to investigate the performance of composite seals comprising juxtaposed blocks of highly compacted bentonite clay and bitumen. It is shown that interaction of the materials can promote a self-sealing mechanism which prevents weather penetration, even when defects are present in the bitumen layer. Factors affecting seal performance are examined by means of laboratory experiments, and implications for the design of repository backfilling and sealing systems are discussed. It is concluded that design principles and material specifications should be further developed on the basis of large scale experiments. (author)

  5. Swell Gels to Dumbbell Micelles: Construction of Materials and Nanostructure with Self-assembly

    Science.gov (United States)

    Pochan, Darrin

    2007-03-01

    Bionanotechnology, the emerging field of using biomolecular and biotechnological tools for nanostructure or nanotecnology development, provides exceptional opportunity in the design of new materials. Self-assembly of molecules is an attractive materials construction strategy due to its simplicity in application. By considering peptidic or charged synthetic polymer molecules in the bottom-up materials self-assembly design process, one can take advantage of inherently biomolecular attributes; intramolecular folding events, secondary structure, and electrostatic interactions; in addition to more traditional self-assembling molecular attributes such as amphiphilicty, to define hierarchical material structure and consequent properties. Several molecular systems will be discussed. Synthetic block copolymers with charged corona blocks can be assembled in dilute solution containing multivalent organic counterions to produce micelle structures such as toroids. These ring-like micelles are similar to the toroidal bundling of charged semiflexible biopolymers like DNA in the presence of multivalent counterions. Micelle structure can be tuned between toroids, cylinders, and disks simply by using different concentrations or molecular volumes of organic counterion. In addition, these charged blocks can consist of amino acids as monomers producing block copolypeptides. In addition to the above attributes, block copolypeptides provide the control of block secondary structure to further control self-assembly. Design strategies based on small (less than 24 amino acids) beta-hairpin peptides will be discussed. Self-assembly of the peptides is predicated on an intramolecular folding event caused by desired solution properties. Importantly, the intramolecular folding event impart a molecular-level mechanism for environmental responsiveness at the material level (e.g. infinite change in viscosity of a solution to a gel with changes in pH, ionic strength, temperature).

  6. CO 2 Capture Capacity and Swelling Measurements of Liquid-like Nanoparticle Organic Hybrid Materials via Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy

    KAUST Repository

    Park, Youngjune

    2012-01-12

    Novel nanoparticle organic hybrid materials (NOHMs), which are comprised of organic oligomers or polymers tethered to an inorganic nanosized cores of various sizes, have been synthesized, and their solvating property for CO 2 was investigated using attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy. Simultaneous measurements of CO 2 capture capacity and swelling behaviors of polyetheramine (Jeffamine M-2070) and its corresponding NOHMs (NOHM-I-PE2070) were reported at temperatures of (298, 308, 323 and 353) K and CO 2 pressure conditions ranging from (0 to 5.5) MPa. The polymeric canopy, or polymer bound to the nanoparticle surface, showed significantly less swelling behavior with enhanced or comparable CO 2 capture capacity compared to pure unbound polyetheramine. © 2011 American Chemical Society.

  7. Hotspot swells revisited

    Science.gov (United States)

    King, Scott D.; Adam, Claudia

    2014-10-01

    The first attempts to quantify the width and height of hotspot swells were made more than 30 years ago. Since that time, topography, ocean-floor age, and sediment thickness datasets have improved considerably. Swell heights and widths have been used to estimate the heat flow from the core-mantle boundary, constrain numerical models of plumes, and as an indicator of the origin of hotspots. In this paper, we repeat the analysis of swell geometry and buoyancy flux for 54 hotspots, including the 37 considered by Sleep (1990) and the 49 considered by Courtillot et al. (2003), using the latest and most accurate data. We are able to calculate swell geometry for a number of hotspots that Sleep was only able to estimate by comparison with other swells. We find that in spite of the increased resolution in global bathymetry models there is significant uncertainty in our calculation of buoyancy fluxes due to differences in our measurement of the swells’ width and height, the integration method (volume integration or cross-sectional area), and the variations of the plate velocities between HS2-Nuvel1a (Gripp and Gordon, 1990) and HS3-Nuvel1a (Gripp and Gordon, 2002). We also note that the buoyancy flux for Pacific hotspots is in general larger than for Eurasian, North American, African and Antarctic hotspots. Considering that buoyancy flux is linearly related to plate velocity, we speculate that either the calculation of buoyancy flux using plate velocity over-estimates the actual vertical flow of material from the deep mantle or that convection in the Pacific hemisphere is more vigorous than the Atlantic hemisphere.

  8. Foot, leg, and ankle swelling

    Science.gov (United States)

    Swelling of the ankles - feet - legs; Ankle swelling; Foot swelling; Leg swelling; Edema - peripheral; Peripheral edema ... Foot, leg, and ankle swelling is common when the person also: Is overweight Has a blood clot in the leg Is older Has ...

  9. Side Effects: Edema (Swelling)

    Science.gov (United States)

    Edema is a condition in which fluid builds up in your body’s tissues. The swelling may be caused by chemotherapy, cancer, and conditions not related to cancer. Learn about signs of edema, including swelling in your feet, ankles, and legs.

  10. Neck Swelling (Symptom Checker)

    Science.gov (United States)

    ... Infants and Children Chest Pain, Acute Chest Pain, Chronic Cold and Flu Cough Diarrhea Ear Problems Elimination Problems Elimination Problems in Infants and Children Eye Problems Facial Swelling Feeding Problems in Infants ...

  11. An analysis of the factors affecting the hydraulic conductivity and swelling pressure of Kyungju ca-bentonite for use as a clay-based sealing material for a high level waste repository

    International Nuclear Information System (INIS)

    Cho, Won Jin; Lee, Jae Owen; Kwon, Sang Ki

    2012-01-01

    The buffer and backfill are important components of the engineered barrier system in a high-level waste repository, which should be constructed in a hard rock formation at a depth of several hundred meters below the ground surface. The primary function of the buffer and backfill is to seal the underground excavation as a preferred flow path for radionuclide migration from the deposited high-level waste. This study investigates the hydraulic conductivity and swelling pressure of Kyungju Ca-bentonite, which is the candidate material for the buffer and backfill in the Korean reference high-level waste disposal system. The factors that influence the hydraulic conductivity and swelling pressure of the buffer and backfill are analyzed. The factors considered are the dry density, the temperature, the sand content, the salinity and the organic carbon content. The possibility of deterioration in the sealing performance of the buffer and backfill is also assessed.

  12. Swelling, mechanical and friction properties of PVA/PVP hydrogels after swelling in osmotic pressure solution.

    Science.gov (United States)

    Shi, Yan; Xiong, Dangsheng; Liu, Yuntong; Wang, Nan; Zhao, Xiaoduo

    2016-08-01

    The potential of polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP) hydrogels as articular cartilage replacements was in vitro evaluated by using a macromolecule-based solution to mimic the osmotic environment of cartilage tissue. The effects of osmotic pressure solution on the morphology, crystallinity, swelling, mechanical and friction properties of PVA/PVP hydrogels were investigated by swelling them in non-osmotic and osmotic pressure solutions. The results demonstrated that swelling ratio and equilibrium water content were greatly reduced by swelling in osmotic solution, and the swelling process was found to present pseudo-Fickian diffusion character. The crystallization degree of hydrogels after swelling in osmotic solution increased more significantly when it compared with that in non-osmotic solution. After swelling in osmotic solution for 28days, the compressive tangent modulus and storage modulus of hydrogels were significantly increased, and the low friction coefficient was reduced. However, after swelling in the non-osmotic solution, the compressive tangent modulus and friction coefficient of hydrogels were comparable with those of as-prepared hydrogels. The better material properties of hydrogels in vivo than in vitro evaluation demonstrated their potential application in cartilage replacement. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Spinal cord swelling and candidiasis

    Energy Technology Data Exchange (ETDEWEB)

    Ho, K.; Gronseth, G.; Aldrich, M.; Williams, A.

    1982-11-01

    Fusiform swelling of the spinal cord was noted myelographically in a patient with Hodgkin's disease. Autopsy revealed that the swelling was caused by Candida infection of the spinal cord. It is suggested that fungal infection be included in the differential diagnosis of spinal cord swelling in the immunosuppressed cancer patient.

  14. Spinal cord swelling and candidiasis

    International Nuclear Information System (INIS)

    Ho, K.; Gronseth, G.; Aldrich, M.; Williams, A.

    1982-01-01

    Fusiform swelling of the spinal cord was noted myelographically in a patient with Hodgkin's disease. Autopsy revealed that the swelling was cauused by Candida infection of the spinal cord. It is suggested that fungal infection be included in the differential diagnosis of spinal cord swelling in the immunsupporessed cancer patient. (orig.)

  15. Mitochondrial Swelling Induced by Glutathione

    Science.gov (United States)

    Lehninger, Albert L.; Schneider, Marion

    1959-01-01

    Reduced glutathione, in concentrations approximating those occurring in intact rat liver, causes swelling of rat liver mitochondria in vitro which is different in kinetics and extent from that yielded by L-thyroxine. The effect is also given by cysteine, which is more active, and reduced coenzyme A, but not by L-ascorbate, cystine, or oxidized glutathione. The optimum pH is 6.5, whereas thyroxine-induced swelling is optimal at pH 7.5. The GSH-induced swelling is not inhibited by DNP or dicumarol, nor by high concentrations of sucrose, serum albumin, or polyvinylpyrrolidone, in contrast to thyroxine-induced swelling. ATP inhibits the GSH swelling, but ADP and AMP are ineffective. Mn-+ is a very potent inhibitor, but Mg++ is ineffective. Ethylenediaminetetraacetate is also an effective inhibitor of GSH-induced swelling. The respiratory inhibitors amytal and antimycin A do not inhibit the swelling action of GSH, but cyanide does; these findings are consistent with the view that the oxidation-reduction state of the respiratory chain between cytochrome c and oxygen is a determinant of GSH-induced swelling. Reversal of GSH-induced swelling by osmotic means or by ATP in KCl media could not be observed. Large losses of nucleotides and protein occur during the swelling by GSH, suggesting that the action is irreversible. The characteristically drastic swelling action of GSH could be prevented if L-thyroxine was also present in the medium. PMID:13630941

  16. Local CO2-induced swelling of shales

    Science.gov (United States)

    Pluymakers, Anne; Dysthe, Dag Kristian

    2017-04-01

    In heterogeneous shale rocks, CO2 adsorbs more strongly to organic matter than to the other components. CO2-induced swelling of organic matter has been shown in coal, which is pure carbon. The heterogeneity of the shale matrix makes an interesting case study. Can local swelling through adsorption of CO2 to organic matter induce strain in the surrounding shale matrix? Can fractures close due to CO2-induced swelling of clays and organic matter? We have developed a new generation of microfluidic high pressure cells (up to 100 bar), which can be used to study flow and adsorption phenomena at the microscale in natural geo-materials. The devices contain one transparent side and a shale sample on the other side. The shale used is the Pomeranian shale, extracted from 4 km depth in Poland. This formation is a potential target of a combined CO2-storage and gas extraction project. To answer the first question, we place the pressure cell under a Veeco NT1100 Interferometer, operated in Vertical Scanning Interferometry mode and equipped with a Through Transmissive Media objective. This allows for observation of local swelling or organic matter with nanometer vertical resolution and micrometer lateral resolution. We expose the sample to CO2 atmospheres at different pressures. Comparison of the interferometry data and using SEM-EDS maps plus optical microscopy delivers local swelling maps where we can distinguish swelling of different mineralogies. Preliminary results indicate minor local swelling of organic matter, where the total amount is both time- and pressure-dependent.

  17. Morphing of geometric composites via residual swelling.

    Science.gov (United States)

    Pezzulla, Matteo; Shillig, Steven A; Nardinocchi, Paola; Holmes, Douglas P

    2015-08-07

    Understanding and controlling the shape of thin, soft objects has been the focus of significant research efforts among physicists, biologists, and engineers in the last decade. These studies aim to utilize advanced materials in novel, adaptive ways such as fabricating smart actuators or mimicking living tissues. Here, we present the controlled growth-like morphing of 2D sheets into 3D shapes by preparing geometric composite structures that deform by residual swelling. The morphing of these geometric composites is dictated by both swelling and geometry, with diffusion controlling the swelling-induced actuation, and geometric confinement dictating the structure's deformed shape. Building on a simple mechanical analog, we present an analytical model that quantitatively describes how the Gaussian and mean curvatures of a thin disk are affected by the interplay among geometry, mechanics, and swelling. This model is in excellent agreement with our experiments and numerics. We show that the dynamics of residual swelling is dictated by a competition between two characteristic diffusive length scales governed by geometry. Our results provide the first 2D analog of Timoshenko's classical formula for the thermal bending of bimetallic beams - our generalization explains how the Gaussian curvature of a 2D geometric composite is affected by geometry and elasticity. The understanding conferred by these results suggests that the controlled shaping of geometric composites may provide a simple complement to traditional manufacturing techniques.

  18. Swelling in neutron-irradiated titanium alloys

    International Nuclear Information System (INIS)

    Peterson, D.T.

    1982-04-01

    Immersion density measurements have been performed on a series of titanium alloys irradiated in EBR-II to a fluence of 5 x 10 22 n/cm 2 (E > 0.1 MeV) at 450 and 550 0 C. The materials irradiated were the near-alpha alloys Ti-6242S and Ti-5621S, the alpha-beta alloy Ti-64, and the beta alloy Ti-38644. Swelling was observed in all alloys with the greater swelling being observed at 550 0 C. Microstructural examination revealed the presence of voids in all alloys. Ti-38644 was found to be the most radiation resistant. Ti-6242S and Ti-5621S also displayed good radiation resistance, whereas considerable swelling and precipitation were observed in Ti-64 at 550 0 C

  19. Cell swelling and volume regulation

    DEFF Research Database (Denmark)

    Hoffmann, Else Kay

    1992-01-01

    been reported. The role of the different channels was discussed. A taurine leak pathway is clearly activated after cell swelling both in astrocytes and in neurones. The relations between the effect of glutamate and cell swelling were discussed. Discussion on the clearance of potassium from...

  20. Swelling of the buffer of KBS-3V deposition hole

    International Nuclear Information System (INIS)

    Lempinen, A.

    2006-12-01

    At the time of the installation of spent nuclear fuel canister in the KBS-3V deposition hole, empty space is left around bentonite buffer for technical reasons. The gap between the buffer and the canister is about 10 mm, and the gap between the buffer and the rock is 30 to 35 mm. In this study, the swelling of the buffer to fill the gaps was simulated, when the gaps are initially filled with water and no external water is available. The model used here is a thermodynamical model for swelling clay, with parameters determined for bentonite. The simulations presented here were performed with Freefem++ software, which is a finite element application for partial differential equations. These equations come from the material model. The simulation results show that the swelling fills the outer gaps in few years, but no significant swelling pressure is generated. For swelling pressure, external water supply is required. (orig.)

  1. Osmotic de-swelling and swelling of latex dispersions

    International Nuclear Information System (INIS)

    Bonnet-Gonnet, Cecile

    1993-01-01

    This research thesis reports the comparison of, on the one hand, direct measurements of de-swelling resistance of latex dispersions obtained by osmotic pressure with, on the other hand, predictions made by models of electrostatic interactions. This resistance is explained in the case of sulphate-stabilised polystyrene particles (direct repulsion between charged particles), and in the case of copolymer (ps-pba) particles covered by an amphiphilic polymer (interactions between surface macromolecules and polymers). The study of de-swelling and swelling cycles highlights the existence of thresholds beyond which the concentrated dispersion has some cohesion. This irreversibility can be modelled by a Van der Waals attraction. The role of hydrophobic forces in latex destabilisation is studied [fr

  2. Cystic swellings of scrotum: Management

    Directory of Open Access Journals (Sweden)

    Subith Kumar K, Sasikumar J, Seetharamaiah T, Ajay Kumar B, Venugopalacharyulu N CH

    2014-04-01

    Full Text Available The cystic swellings of scrotum are one among the commonest clinical entities faced by a surgeon in day to day practice and a cause of concern to the patient more with his fertility. Presenting with varied etiology they can represent a wide range of medical issues. Gold standard for the management of such cystic swellings of scrotum continues to be surgical extirpation of the lesion. Objective: To identify the cause, mode of presentation, various modalities of treatment and outcome of these with their complications. Method: A total of 170 cases of cystic swellings of scrotum fulfilling the methodology criteria were subjected to the preformatted study. Diagnosis was mostly by clinical examination and supported by ultrasonography. All cases were treated surgically with the appropriate surgical procedure. Results: Maximum patients were in the age group of 31-50 years and presented with scrotal swelling (59% and more commonly affecting the right side. The commonest cause for cystic swelling of the scrotum was primary vaginal hydrocele (55%. Surgical procedure using Lords Plication was found to be simple, effective and associated with minimum post operative complications; the other conventional techniques like Partial/sub-total excision of sac, everson of sac were associated with more complications like haematoma, scrotal edema and infection. Majority of patients were discharged on 7th Post-operative day. Conclusion: The present study, primary vaginal hydrocele was the commonest cystic swelling of scrotum and treated surgically showed good results. Lord’s procedure was associated with the less post-operative complications, minimal tissue handling and good haemostatic control.

  3. Swelling and microstructure of neutrons irradiated 316 Ti SS

    International Nuclear Information System (INIS)

    Seran, J.L.; Le Naour, L.; Grosjean, P.; Hugon, M.P.; Carteret, Y.; Maillard, A.

    1984-06-01

    The analysis of the behaviour of fuel pins irradiated in the same RAPSODIE subassembly, shows that titanium has a marked beneficial effect on the swelling resistance of CW 316 SS in a large range of temperature. This effect is particularly visible at high temperature since CW 316 Ti SS does not swell above 550 0 C up to a dose of 100 French dpa. The results obtained on samples irradiated in a RAPSODIE experimental rig give us confirmation of the good behaviour of CW 316 Ti SS which swells less and at smaller temperature than the other steels of the 316 series such as SA 316 Ti or aged SA 316 Ti. The swelling differences between some of these materials can be associated to different microstructures which are also very different from the ones obtained on the irradiated steels aged in the same time and temperature conditions

  4. Specimen Machining for the Study of the Effect of Swelling on CGR in PWR Environment.

    Energy Technology Data Exchange (ETDEWEB)

    Teysseyre, Sebastien Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-06-01

    This report describes the preparation of ten specimens to be used for the study of the effect of swelling on the propagation of irradiation assisted stress corrosion cracking cracks. Four compact tension specimens, four microscopy plates and two tensile specimens were machined from a AISI 304 material that was irradiated up to 33 dpa. The specimens had been machined such as to represent the behavior of materials with 3.7%swelling and <2% swelling.

  5. Development of simulation technique and examination of mechanism for swelling of steam generator tube

    International Nuclear Information System (INIS)

    Kim, Seon Jin; Kim, Ki Nam; Park, Myung Chul; Shin, Gyeong Su; Cho, Jae Hwan

    2010-05-01

    This study was aimed at identifying the mechanism of the swelling through the development of simulation techniques for the swelling of steam generator tubes and correct understanding of swelling so as to evaluate the effect of swelling on soundness of steam generator based on results of the study. Test apparatus designed to simulate the tube swelling was fabricated and through a number of preliminary experiments at different conditions, swelling simulation was successfully completed. A tube swelling phenomenon is caused by a sort of ratcheting which is analyzable and is considered as a sort of fatigue phenomenon in which the stress is accumulated by action/reaction moment resulting from repeated impact of low energy, despite of hoop stress by internal pressure is significantly lower than yield strength of the material which has effect on hoop stress, overcoming the yield strength and causing the tubes to suffer plastic deformation

  6. Site-Specific Pre-Swelling-Directed Morphing Structures of Patterned Hydrogels.

    Science.gov (United States)

    Wang, Zhi Jian; Hong, Wei; Wu, Zi Liang; Zheng, Qiang

    2017-12-11

    Morphing materials have promising applications in various fields, yet how to program the self-shaping process for specific configurations remains a challenge. Herein we show a versatile approach to control the buckling of individual domains and thus the outcome configurations of planar-patterned hydrogels. By photolithography, high-swelling disc gels were positioned in a non-swelling gel sheet; the swelling mismatch resulted in out-of-plain buckling of the disc gels. To locally control the buckling direction, masks with holes were used to guide site-specific swelling of the high-swelling gel under the holes, which built a transient through-thickness gradient and thus directed the buckling during the subsequent unmasked swelling process. Therefore, various configurations of an identical patterned hydrogel can be programmed by the pre-swelling step with different masks to encode the buckling directions of separate domains. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Influence of swelling on irradiated cw 316 Ti embrittlement

    International Nuclear Information System (INIS)

    Fissolo, A.; Cauvain, R.; Hugot, J.P.; Levy, V.

    1988-01-01

    For fast breeder reactors core materials, the main limitations are usually swelling and irradiation embrittlement. Tensile tests and Charpy tests performed on CW 316 Ti wrappers irradiated in PHENIX up to 100 dpa NRT have shown strong evidence of correlation between swelling and embrittlement. Tensile tests were performed at room temperature, at 200 0 C and at irradiation temperature on tensile specimens machined from wrappers; the tests were done on different heats leading to different swelling values. Charpy tests were performed also at room temperature, 200 0 C and irradiation temperature, on Charpy specimens machined from different wrappers. As swelling increases, first we observe a large decrease of the total energy absorbed by specimen rupture in Charpy tests and the absence of necking before failure in tensile tests; when swelling reaches about 6 %, the total energy in Charpy tests becomes very low and uniform elongation in tensile tests decreases; at higher swelling values failure in tensile tests may occur without any plastic deformation, the UTS itself decreasing sharply

  8. Cell swelling and volume regulation

    DEFF Research Database (Denmark)

    Hoffmann, Else Kay

    1992-01-01

    The extracellular space in the brain is typically 20% of the tissue volume and is reduced to at least half its size under conditions of neural insult. Whether there is a minimum size to the extracellular space was discussed. A general model for cell volume regulation was presented, followed...... by a discussion on how many of the generally involved mechanisms are identified in neural cells and (or) in astrocytes. There seems to be clear evidence suggesting that parallel K+ and Cl- channels mediate regulatory volume decrease in primary cultures of astrocytes, and a stretch-activated cation channel has...... been reported. The role of the different channels was discussed. A taurine leak pathway is clearly activated after cell swelling both in astrocytes and in neurones. The relations between the effect of glutamate and cell swelling were discussed. Discussion on the clearance of potassium from...

  9. Swelling-resistant nuclear fuel

    Science.gov (United States)

    Arsenlis, Athanasios [Hayward, CA; Satcher, Jr., Joe; Kucheyev, Sergei O [Oakland, CA

    2011-12-27

    A nuclear fuel according to one embodiment includes an assembly of nuclear fuel particles; and continuous open channels defined between at least some of the nuclear fuel particles, wherein the channels are characterized as allowing fission gasses produced in an interior of the assembly to escape from the interior of the assembly to an exterior thereof without causing significant swelling of the assembly. Additional embodiments, including methods, are also presented.

  10. Laboratory study of the Flandres clay swelling

    International Nuclear Information System (INIS)

    Khaddaj, Said

    1992-01-01

    The first chapter contains a survey about the swelling of soils, and about the experimental methods used to characterize this phenomenon. A classification of soils in function of their swelling potential is proposed. The second chapter deals with the properties of Flandres clay. Chemical and mineralogical compositions, mechanical properties and free swell index are given. The third chapter contains a presentation of the study of the swelling potential of Flandres clay using the oedometer. Four methods are described and used (free-swell, different pressures, pre-swell and direct-swell). A numerical simulation of free-swell tests is also given. The fourth chapter includes a presentation of the study of the swelling behaviour of Flandres clay using a triaxial cell. Three methods are used: free-swell, pre-swell and different-pressures. The last chapter contains a parametric study of the swelling behaviour of Flandres clay. The influence of some parameters such as sample thickness, initial water content, vertical load and load history is presented. (author) [fr

  11. Synthesis, rheological behavior and swelling properties of ...

    African Journals Online (AJOL)

    Bulletin of the Chemical Society of Ethiopia ... The swelling response of the copolymers networks as a function of time, temperature and swelling environment has been observed to be dependent on both structural ... The swelling has been observed to be decrease with increase in MBAAm in the copolypolymers networks.

  12. Inferring Properties of the Hawaiian Plume from the Hawaiian Swell

    Science.gov (United States)

    Ribe, N. M.

    2012-04-01

    The most prominent geophysical signature associated with the Hawaiian island chain is a broad topographic anomaly ('swell') some 1000 km wide and 2500 km long. Isostasy requires the swell to be compensated by a layer of low-density material at depth whose shape in mapview is similar to that of the swell itself. That shape can be predicted using a simple 2-D thin-layer flow model in which buoyant fluid with constant viscosity is supplied at a volumetric rate Q by a fixed mantle plume and spreads laterally over the base of a plate moving at speed U. A more realistic 3-D version of the model involves a hot thermal plume in a fluid with temperature- and pressure-dependent viscosity that interacts with the shear flow generated by the plate motion. Comparison of the predictions of these models with observations of the Hawaiian swell yields several important inferences about the Hawaiian plume: (1) Plume buoyancy flux B. The observed height and width of the swell imply B ≈ 3000 kg s-1, much less than earlier estimates B = 6300-8700 kg s-1 based solely on the horizontal flux of (negative) swell buoyancy carried by the moving plate. The reason for the discrepancy is that the horizontal flux calculation neglects (a) the contribution of the buoyant residue of partial melting to the swell topography, and (b) the fact that the mean speed of downstream transport of the buoyant material by the shear flow is less than the plate speed. (2) Depth of compensation. The 3-D model predicts a geoid/topography ratio (GTR) ≈ 7-8 m/km for the Hawaiian swell, in apparent contradiction with earlier estimates ≈ 4-5 m/km based on the observed geoid and bathymetry alone. However, an extended version of the 3-D model including volcanic loading and lithospheric flexure reveals that the low values GTR≈ 4-5 m/km are artifacts of incomplete removal of the shallowly compensated volcanic islands and the surrounding flexural moat. The GTR of the swell itself is therefore ≈ 7-8 m/km, implying a

  13. Critical swelling of fluctuating capsules

    Science.gov (United States)

    Diamant, Haim; Haleva, Emir

    2009-03-01

    In many natural transport processes the solute molecules to be transported are encapsulated in semipermeable, flexible membrane vesicles of micron size. We study the swelling of such fluctuating capsules, as the number of encapsulated particles is increased, or the concentration of the outer solution is decreased. The approach to the maximum volume-to-area ratio and the associated buildup of membrane tension involve a continuous phase transition and follow universal scaling laws. The criticality and its features are model-independent, arising solely from the interplay between volume and surface degrees of freedom.ootnotetextE. Haleva and H. Diamant, Phys. Rev. Lett. 101, 078104 (2008).

  14. Effect of metallurgical variables on void swelling

    International Nuclear Information System (INIS)

    Johnston, W.G.; Lauritzen, T.; Rosolowski, J.H.; Turkalo, A.M.

    1976-01-01

    The mechanism of void swelling is reviewed briefly and the anticipated effects of metallurgical variables are described. Experimental results showing the effects of metallurgical variables are reviewed, most of the work being done by simulation methods employing charged particle bombardments to simulate reactor damage. Although the early emphasis was on structural variables such as grain size, cold work and precipitates to control swelling, it now seems that the practical reduction of swelling will be achieved by modifying alloy composition. Void swelling is strongly influenced by the relative amounts of Fe, Cr, and Ni in an alloy; the amount of swelling can be varied by three orders of magnitude by changing the relative amounts of the three elements in an austenitic ternary alloy. The effect of composition on swelling of a simple ferritic alloy will also be described. The swelling of a simple austenitic alloy of Fe, Cr, and Ni can be reduced by certain minor element additions. The most effective swelling inhibitors are Si, Ti, Zr, and Nb, and combinations of Si and Ti are synergetic. Swelling reductions of two orders of magnitude have been achieved with combined additions. Predictions of swelling in commercial solid solution alloys are made on the basis of the present knowledge of the effects of major composition and minor element additions. The predictions agree with experimental results. For more complex commercial alloys, predictions are made for the effects on swelling of heat treatments that cause changes in matrix composition. In some cases, heat treatment is expected to change the peak swelling by more than a factor of ten, and to shift the peak swelling temperature by almost 100 0 C. Sensitivity of swelling to detailed matrix composition places emphasis on the need for developing understanding of the stability of structure and local composition in an irradiation environment

  15. investigating water absorption and thickness swelling tendencies of ...

    African Journals Online (AJOL)

    HOD

    INVESTIGATING WATER ABSORPTION AND THICKNESS SWELLING TENDENCIES OF POLYMERIC COMPOSITE … O. Adekomaya & K. Adama. Nigerian Journal of Technology,. Vol. 37, No. 1, January 2018. 169. Table 2: Physical and thermal properties of epoxy resin materials (Adapted from manufacturer data sheet).

  16. Laboratory tests of hydraulic fracturing and swell healing

    DEFF Research Database (Denmark)

    Thunbo, Christensen Claes; Foged, Christensen Helle; Foged, Niels

    1998-01-01

    New laboratory test set-ups and test procedures are described - for testing the formation of hydraulically induced fractures as well as the potential for subsequent fracture closurefrom the relase of a swelling potential. The main purpose with the tests is to provide information on fracturing...... stresses and whether or not the material in question possesses the potential for fracture closure....

  17. Swelling Characteristics and Tensile Properties of Natural Fiber ...

    African Journals Online (AJOL)

    Swelling characteristics of samples of this composite material were determined by monitoring- forth nightly, changes in weight of the samples within the test period and tensile test was conducted on the samples after 16 weeks using Hounsfeild (Monsanto) tensometer. The results show that the solvents reduced the strengths ...

  18. STUDY OF A SOIL WITH SWELLING AND SHRINKING PHENOMENA

    Directory of Open Access Journals (Sweden)

    G. Rogobete

    2012-12-01

    Full Text Available Vertisols are deep clayey soils, with more than 45 % clay, dominated by clay minerals, such as smectites, that expand upon wetting and shrink upon drying. The most important physical characteristics of Vertisols are a low hydraulic conductivity and stickiness when wet and high flow of water through the cracks when dry. They become very hard when dry and in all the time are difficult to work. During the rainy season, the cracks disappear and the soil becomes sticky and plastic with a very slippery surface which makes Vertisols in – trafficable when wet. Water movement in soil that change volume with water content is not well understood and management of swelling soil remains problematic. Swelling or shrinking result in vertical displacement of the wet soil, which involves gravitational work and contributes to an overburden component to the total potential of the soil water. Many swelling soil crack and the network of cracks provides pathways for rapid flow of water which prejudice application of theory based on Darcian flow. One – dimensional flow of water in a swelling system requires material balance equation for both the aqueous and solid phases. The analytical data offers some values particle – size distribution, compression, swelling degree and pressure, plasticity index, elastic modulus, triaxial shear, angle of shear and load carrying capacity in order to realize a foundation study for some constructions.

  19. Overview of the swelling behavior of 316 stainless steel

    International Nuclear Information System (INIS)

    Garner, F.A.

    1984-01-01

    The austenitic stainless steel designated as AISI 316 is currently being used as the major structural material for fast breeder reactors in the United States, Britain and France. Efforts are now underway in each country to optimize the swelling resistance of this alloy for further application to both fission and fusion power generating devices. The optimization effort requires knowledge of the factors which control swelling in order that appropriate compositional and fabricational modifications can be made to the alloy specification. The swelling data for this alloy are reviewed and the conclusion is reached that optimization efforts must focus on the incubation or transient regime of swelling rather than the post-transient or ''steady-state'' regime. Attempts to reduce the swelling of this steel by solute modification have focused on elements such as phosphorus and titanium. It is shown that the action of these solutes is manifested only in their ability to extend the transient regime. It is also shown that irradiation at high helium/dpa ratios does not appear to change the conclusions of this study. Another important conclusion is that small differences in reactor environmental history can have a larger influence than either helium or solutes. 31 refs., 27 figs., 1 tab

  20. A volatile tracer-assisted headspace analytical technique for determining the swelling capacity of superabsorbent polymers.

    Science.gov (United States)

    Zhang, Shu-Xin; Jiang, Ran; Chai, Xin-Sheng

    2017-09-01

    This paper reports on a new method for the determination of swelling capacity of superabsorbent polymers by a volatile tracer-assisted headspace gas chromatography (HS-GC). Toluene was used as a tracer and added to the solution for polymers swelling test. Based on the differences of the tracer partitioned between the vapor and hydrogel phase before and after the polymer's swelling capacity, a transition point (corresponding to the material swelling capacity) can be observed when plotting the GC signal of toluene vs. the ratio of solution added to polymers. The present method has good precision (RSDpolymers at the elevated temperatures. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Effect of geometric scale on the extrudate swell of plastic micro-tubes

    Science.gov (United States)

    Ren, Zhong; Huang, Xingyuan

    2018-01-01

    In this study, the effect of geometric scale on the extrudate swell of plastic micro-tubes was numerically studied by using the finite element method. The four geometric models with same inner diameter but different wall thicknesses were used. Under the same boundary conditions, material parameters, and numerical algorithms, the extrudate swells and flow field distributions of two plastic micro-tubes were obtained. Study results show that the extrudate swell effect of plastic micro-tubes increase with the decreasing of geometric scale. Finally, the mechanisms of the geometric scale on the extrudate swell for the plastic micro-tubes were analyzed.

  2. High dose stainless steel swelling data on interior and peripheral oxide fuel pins

    International Nuclear Information System (INIS)

    Boltax, A.; Foster, J.P.; Nayak, U.P.

    1983-01-01

    High dose (2 x 10 23 n/cm 2 , E > 0.1 Mev) swelling data obtained on 20% cold-worked AISI 316 stainless steel (N-lot) cladding from mixed-oxide fuel pins show large differences in swelling incubation dose due to pre-incubation dose temperature changes. Circumferential swelling variations of 1.5 to 4 times were found in peripheral fuel pin cladding which experienced 30 to 60 deg C temperature changes due to movement in a temperature gradient. Consideration is given to the implications of these results to low swelling materials development and core design. (author)

  3. Mechanical properties, anisotropic swelling behaviours and structures of jellyfish mesogloea.

    Science.gov (United States)

    Zhu, Jintang; Wang, Xuezhen; He, Changcheng; Wang, Huiliang

    2012-02-01

    Learning from nature is a promising way for designing and fabricating new materials with special properties. As the first step, we need to understand the structures and properties of the natural materials. In this work, we paid attention to the mesogloea of an edible jellyfish (Rhopilema esculenta Kishinouye) and mainly focused on its structure, mechanical and swelling properties. Scanning electron microscope (SEM) investigations show that jellyfish mesogloea has a well-developed anisotropic microstructure, which consists of nano-sized membranes connected with many fibres. The tensile and compressive properties of swollen and dried jellyfish mesogloea samples are measured. The jellyfish mesogloea displays very high tensile strength (0.17 MPa) and compressive strength (1.43 MPa) even with 99 wt % water. The mechanical properties of jellyfish mesogloea exceed most synthetic hydrogels with similar or even lower water contents. Swelling in acidic and basic buffer solutions weakens the mechanical properties of jellyfish mesogloea. The dried jellyfish mesogloea has very high tensile strength and modulus, which are very similar to those of synthetic plastics. The swelling properties of jellyfish mesogloea in solutions with different pH values were studied. The jellyfish mesogloea exhibits pH-sensitive and anisotropic swelling properties. The jellyfish mesogloea swells (expands) in height but deswells (shrinks) in length and width, without significant change in the volume. This phenomenon has never been reported for synthetic hydrogels. This study may provide gel scientists new ideas in designing and fabricating hydrogels with well-defined microstructures and unique mechanical and swelling properties. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Swelling soils in the road structures

    Science.gov (United States)

    Pruška, Jan; Šedivý, Miroslav

    2017-09-01

    There are frequent problems with the soil swelling in the road construction in the past time. This phenomenon is known for decades. This situation is notably given by insufficient knowledge of this problem and difficulties with input parameters describing the swelling process. The paper in the first part proposed regression relations to predict swelling pressure, time of swelling and swelling strain for different initial water contents for soils and improvement soils. The relations were developed by using artificial neural network and QCExpert Professional software (on the data from site investigations by GeoTec-GS, a.s. and experimental data from CTU in Prague). The advantage of the relations is based on using the results of the basic soil tests (plasticity index, consistency index and colloidal activity) as input parameters. The authors inform the technical public with their current knowledge of the problems with the soil swelling on the motorway in the second part of the paper.

  5. Soil shrinkage characteristics in swelling soils

    International Nuclear Information System (INIS)

    Taboada, M.A.

    2004-01-01

    The objectives of this presentation are to understand soil swelling and shrinkage mechanisms, and the development of desiccation cracks, to distinguish between soils having different magnitude of swelling, as well as the consequences on soil structural behaviour, to know methods to characterize soil swell/shrink potential and to construct soil shrinkage curves, and derive shrinkage indices, as well to apply them to assess soil management effects

  6. Large swelling and percolation in irradiated zircon

    CERN Document Server

    Trachenko, K; Salje, E K H

    2003-01-01

    We study the effect of large swelling in irradiated zircon. We perform molecular dynamics simulation of the overlap of two radiation events and find that the damage produced in the second event scatters away from the densified boundary of the damaged region implanted previously. This serves as the microscopic mechanism of the increase of volume occupied by the damage. The additive nature of this effect results in large swelling observed experimentally. We translate the damage accumulation into the percolation problem, and show that volume swelling is a percolation phenomenon, with the swelling curve increasing rapidly at the percolation threshold. (letter to the editor)

  7. Swelling pressure and water absorption property of compacted granular bentonite during water absorption

    International Nuclear Information System (INIS)

    Oyamada, T.; Komine, H.; Murakami, S.; Sekiguchi, T.; Sekine, I.

    2012-01-01

    Document available in extended abstract form only. Bentonite is currently planned to be used as buffer materials in engineered barrier of radioactive waste disposal. Granular bentonites are expected as the materials used in constructions as buffer materials by in-situ compaction methods. After applying these buffer materials, it is expected that the condition of the buffer area changes in long-term by the seepage of groundwater into buffer area. Therefore, it is important to understand water movement and swelling behavior of the buffer materials for evaluating the performance of engineered barrier. In this study, we investigated water absorption property and swelling pressure of compacted granular bentonite. Specifically, the process of swelling pressure and amount of water absorption of granular bentonite-GX (Kunigel-GX, produced at the Tsukinuno mine in Japan) were observed by laboratory tests. To discuss the influence of maximum grain size of bentonite particle on swelling pressure and water absorption property, two types of samples were used. One is granular sample which is Bentonite-GX controlled under 2 mm the maximum grain size, the other is milled sample which is Bentonite-GX with the maximum grain size under 0.18 mm by milling with the agate mortar. In addition, the mechanism on the swelling pressure of compacted granular bentonite was considered and discussed. In the cases of granular sample, swelling pressure increases rapidly, then gradually continues to increase up to maximum value. In the cases of milled sample, swelling pressure also increases rapidly at first. However, then its value decreases before progressing of gradual increase continues. Especially, this trend was clearly observed at a relatively low dry density. At the peaks of these curves, the swelling pressure of granular samples is lower than that of milled samples. In addition, the increasing of swelling pressure by the time the peak observed during the process of swelling pressure from

  8. Coal swelling and thermoplasticity under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Ndaji, F.E.; Butterfield, I.M.; Thomas, K.M. (Newcastle upon Tyne University, Newcastle upon Tyne (United Kingdom). Northern Carbon Research Labs., Dept. of Chemistry)

    1992-01-01

    The literature on the following topics is reviewed: swelling and agglomeration of coal; measurements of swelling index and dilatometric and plastometric properties at high pressures; and the effects of oxidation, tar addition and minerals on high-pressure thermoplastic properties. 34 refs., 6 figs.

  9. Fuel swelling importance in PCI mechanistic modelling

    International Nuclear Information System (INIS)

    Arimescu, V.I.

    2005-01-01

    Under certain conditions, fuel pellet swelling is the most important factor in determining the intensity of the pellet-to-cladding mechanical interaction (PCMI). This is especially true during power ramps, which lead to a temperature increase to a higher terminal plateau that is maintained for hours. The time-dependent gaseous swelling is proportional to temperature and is also enhanced by the increased gas atom migration to the grain boundary during the power ramp. On the other hand, gaseous swelling is inhibited by a compressive hydrostatic stress in the pellet. Therefore, PCMI is the net result of combining gaseous swelling and pellet thermal expansion with the opposing feedback from the cladding mechanical reaction. The coupling of the thermal and mechanical processes, mentioned above, with various feedback loops is best simulated by a mechanistic fuel code. This paper discusses a mechanistic swelling model that is coupled with a fission gas release model as well as a mechanical model of the fuel pellet. The role of fuel swelling is demonstrated for typical power ramps at different burn-ups. Also, fuel swelling plays a significant role in avoiding the thermal instability for larger gap fuel rods, by limiting the potentially exponentially increasing gap due to the positive feedback loop effect of increasing fission gas release and the associated over-pressure inside the cladding. (author)

  10. A FACSIMILE code for calculating void swelling, version VS1

    International Nuclear Information System (INIS)

    Windsor, M.; Bullough, R.; Wood, M.H.

    1979-11-01

    VS1 is the first of a series of FACSIMILE codes that are being made available to predict the swelling of materials under irradiation at different temperatures, using chemical rate equations for the point defect losses to voids, interstitial loops, dislocation network, grain boundaries and foil surfaces. In this report the rate equations used in the program are given together with a detailed description of the code and directions for its use. (author)

  11. The Measurement of Polymer Swelling Processes by an Interferometric Method and Evaluation of Diffusion Coefficients

    Directory of Open Access Journals (Sweden)

    Aleš Mráček

    2010-02-01

    Full Text Available The amorphous polymer film swelling in a liquid solvent below the glass transition temperature was characterized by a few kinetic parameters (especially the mutual diffusion coefficient of swelling and its mean value obtained by interference of monochromatic light in the wedge arrangement. This interferometric method allows one to determine the concentration field in the swollen surface layer and consequently to compute the concentration-dependent diffusion coefficient. A software system developed at the Department of Physics and Material Engineering at TBU in Zlin has been used for the evaluation of the main kinetic parameters of the swelling process. The software can be used for the on-line analyses of interferograms during the swelling process. The main application outputs are the computation of the concentration profile, the concentration gradient, the mutual diffusion coefficient of the swelling by the solvent and its mean value.

  12. Theoretical basis for unified analysis of experimental data and design of swelling-resistant alloys

    International Nuclear Information System (INIS)

    Mansur, L.K.; Lee, E.H.

    1991-01-01

    Essential aspects of the theory of radiation-induced swelling are reviewed. In particular, concepts central to the understanding of experimental data and the control of swelling by alloy design are discussed. The knowledge that a critical number of gas atoms is required in a cavity before point defect-driven swelling can begin is a most important contribution of theory. The mathematical expression that have been derived for calculating this critical quantity are given in terms of materials parameters and irradiation conditions. After swelling begins, its magnitude as a function of dose is governed strongly by the relative sink strengths for point defects of dislocations and cavities, expressed in terms of an index of the microstructure, Q. Hich swelling and low swelling microstructures can be categorized into four types based on this index. Wide ranges of experimental swelling results covering ferritic/martensite and austenitic alloys, neutron and ion irradiations and a variety of compositions and irradiation conditions are analyzed and found to be explained consistently within this framework. Based on the understanding gained, approaches to alloy design for swelling resistance are recommended. (orig.)

  13. Foot Swelling during Air Travel: A Concern?

    Science.gov (United States)

    ... concern? What causes leg and foot swelling during air travel? Answers from Sheldon G. Sheps, M.D. ... had major surgery or you take birth control pills, for example — consult your doctor before flying. He ...

  14. An elastoplastic model of bentonite free swelling

    OpenAIRE

    Pintado, Xavier; Alonso Aperte, Juan; Navarro Gamir, Vicente; Asensio, Laura; Yustres Real, Ángel

    2014-01-01

    This article proposes a new plastification mechanism to model bentonite free swelling processes by using an elastoplastic approach. The formulation is based on an interaction function that defines the plastic macrostructural strains induced by microstructural effects. This term is defined as a function of the microstructural void ratio, and it establishes a direct connection between the destructuration of the micro- and macrostructures of the bentonite during the free swelling processes. The ...

  15. Modelling the hydro-mechanical behaviour of swelling unsaturated soils

    International Nuclear Information System (INIS)

    Mrad, M.

    2005-10-01

    The use of compacted swelling soils in engineering practice is very widely spread, especially in geotechnical and environmental engineering. After their setup, these materials are likely to be subject to complex suction/stress paths involving significant variations of their hydro-mechanical properties which can affect their initial behaviour. It is important to be able to predict the hydro-mechanical behaviour of these materials taking into account the significant applications for which they are intended. Barcelona team developed a finite-element code (Code-Bright) for the thermo-hydro-mechanical coupling (THM) integrating the BBM elastoplastic model for unsaturated soils based on the independent variables approach. This model is recognized to correctly describe the hydro-mechanical behaviour of unsaturated soils but fails to take into account some particular observed aspects on swelling soils. A second model BExM was then proposed to address these aspects. The objective of this study is: (i) to implement the elastoplastic model BExM for the unsaturated swelling soils in the finite-element code (Code-Bright); (ii) to check the numerical model validity through the numerical simulation of laboratory tests made on swelling soils; and (iii) to apply this model to some practical problems. For this purpose, a new family of numerical procedures adapted to the BExM model was introduced into the code. The equation of the yield surface of this model for a given deviatoric stress states was given in a manner to facilitate calculations of its derivatives. The model was checked by the numerical simulation of suction-controlled odometric tests made on three different swelling soils. The simulation results showed that the numerical model is able to correctly reproduce the experimental data. Lastly, the model was applied to two practical problems: radioactive waste repository in deep geological layers and a shallow footing under the action of a swelling soil. The results obtained

  16. Estimates of the eigenvalues of operator arising in swelling pressure model

    Energy Technology Data Exchange (ETDEWEB)

    Kanguzhin, Baltabek [Institute of Mathematics and Mathematical Modeling, 050010, Almaty (Kazakhstan); Zhapsarbayeva, Lyailya [Al-Farabi Kazakh National University, Almaty (Kazakhstan)

    2016-08-10

    Swelling pressures from materials confined by structures can cause structural deformations and instability. Due to the complexity of interactions between expansive solid and solid-liquid equilibrium, the forces exerting on retaining structures from swelling are highly nonlinear. This work is our initial attempt to study a simplistic spectral problem based on the Euler-elastic beam theory and some simplistic swelling pressure model. In this work estimates of the eigenvalues of some initial/boundary value problem for nonlinear Euler-elastic beam equation are obtained.

  17. Swelling compositions based polycarboxylic acids and bentonite clays in solutions of salts of metals

    Directory of Open Access Journals (Sweden)

    A. Sarshesheva

    2012-12-01

    Full Text Available This work is devoted to the synthesis of chemical cross-linked composite materials made of natural inorganic polymer bentonite clay of Manrak deposit, and polyacrylic and polymethacrylic acids. The swelling ability of the composition in solutions of salts of heavy metals (Ni2+ and Pb2+, influence of solution of concentration, pH and temperature on the swelling ability is investigated.

  18. Impact of swelling characteristics on the permselective ...

    Science.gov (United States)

    The removal of water from organic solvents and biofuels, including lower alcohols (i.e., methanol, ethanol, propanol, and butanol), is necessary for the production, blending, and reuse of those organic compounds. Water forms an azeotrope with many hydrophilic solvents, complicating the separation of water/solvent mixtures. The use of water-selective membranes in a pervaporation or vapor permeation process enables the removal of water from the solvents, even when an azeotrope is present. Common hydrophilic polymer membranes often swell in water, resulting in permeabilities and selectivities that are dependent on the water content of the feed mixture. Recent work has shown the benefit of overcoating a hydrophilic water-permselective membrane with a non-swelling perfluoropolymer film [1,2]. The perfluoropolymer layer reduces the activity of water the hydrophilic polymer layer experiences, thereby reducing swelling in that layer and increasing the water selectivity of the multi-layer membrane relative to the selectivity of the base hydrophilic polymer, usually at the expense of permeability. In this work, the effect of overcoating the hydrophilic layer with polymer films of various swelling characteristics was modelled. Top layers that swell in the solvent offer some advantages, particularly with regard to the water permeance of the multi-layer composite. 1. Huang, Y.; Baker, R. W.; Wijmans, J. G. Perfluoro-coated hydrophilic membranes with improved selectivity. In

  19. The Effects of Swelling and Porosity Change on Capillarity: DEM Coupled with a Pore-Unit Assembly Method

    NARCIS (Netherlands)

    Sweijen, T.; Nikooee, E.; Hassanizadeh, S.M.; Chareyre, B.

    In this study, a grain-scale modelling technique has been developed to generate the capillary pressure–saturation curves for swelling granular materials. This model employs only basic granular properties such as particles size distribution, porosity, and the amount of absorbed water for swelling

  20. Swelling pressure of highly compacted bentonite

    International Nuclear Information System (INIS)

    Pusch, R.

    1980-08-01

    Highly compacted, dense Na bentonite is used to isolate metal canisters with highly radioactivity waste products from the surrounding rock. The main object was to investigate the relationship between the swelling pressure and bulk density of bentonite with special reference to the influence of ion exchange and temperature. A new type of oedometer for swelling pressure tests was developed. It was found that there seemed to be unique relationship between the bulk density and the sweeling pressure, and that a temperature increase to 70deg C reduced the pressure to approximately 50% of the value at 20degC. It was observed that the pore water chemistry was hardle a determinant of the swelling pressure in the bulk density above 2 ton per m 3 . (G.B.)

  1. A Hamiltonian Formulation On Tsunami Over Swell

    Science.gov (United States)

    TIAN, M.; Sheremet, A.; Kaihatu, J. M.

    2012-12-01

    Tsunami induced by earthquakes typically evolves shore-ward with a significant amplification of amplitude during the last stages of shoaling. This study focuses on tsunami evolution in shallow water under the effects of the oceanographic environment such as breaking and tsunami- swell interaction. One generally describes wave breaking directly with a discontinuity in the solution to the classical nonlinear shallow water equations (NLSW) (e.g., Stoker 1985). This wave-front steepness calculation, however, has the potential problem that for the case of the single wave defined by solitary wave, breaking occurs much closer to the wave crest so that the method is formally invalid (Madsen et. al. 2008). Li and Raichlen (2002) applied a weighted essentially non-oscillatory (WENO) shock-capturing scheme in the numerical NSWE model to capture the wave breaking process. The problem arises that a convenient hamiltonian formalism is lacking to describe wave breaking. One wants to evaluate breaking by deducing the decay of the tsunami energy in a straightforward manner. The linear effect of the tsunami background circulation on swell is well known (e.g., Madsen et. al. 2008). However, Kaihatu and El Safty(2011) hypothesized that this is only one "half" of the mutual interaction between the tsunami and the overlying swell field, which might have subtle effects on the tsunami front-face steepness and breaking process. These effects were observed in a laboratory experiments (Kaihatu and El Safty 2011). It was observed that the presence of swell affects the maximum surface amplitude of overall wave field and produces significant energy shifts to high frequencies, thus promoting tsunami breaking. The theoretical study for tsunami-swell interaction requires a phase-resolving wave-wave interaction model. In this study, we derive a Hamiltonian formulation for the tsunami-swell interaction using the quasi stream-function formulation. This formalism is better able to handle uneven

  2. Swelling and irradiation creep of neutron irradiated 316Ti and 15-15Ti steels

    International Nuclear Information System (INIS)

    Maillard, A.; Touron, H.; Seran, J.L.; Chalony, A.

    1992-01-01

    The global behavior, the swelling and irradiation creep resistances of cold worked 316Ti and 15-15Ti, two variants of austenitic steels in use as core component materials of the French fast reactors, are compared. The 15-15Ti leads to a significant improvement due to an increase in the incubation dose swelling. The same phenomena observed on 316Ti are found on 15-15Ti. All species without fuel like samples, wrappers or empty clad swell and creep less than fuel pin cladding irradiated in the same conditions. To explain the swelling difference, as for 316Ti, thermal gradient is also invoked but the irradiation creep difference is not yet clearly understood. To predict the behavior of clads it is indispensable to study the species themselves and to use specific rules. All results confirm the good behavior of 15-15Ti, the best behavior being obtained with the 1% Si doped version irradiated up to 115 dpa

  3. Neurofibromas as bilateral cystic chest wall swellings.

    African Journals Online (AJOL)

    clinical entity in our centre. This rare entity should be borne in mind when considering the differential diagnosis of benign cystic chest wall tumours. Key words: neurofibromatosis, cystic swelling, posterior ... We are reporting a single case of bilat- eral cystic degenerative changes in neurofibromas that presented clinically like ...

  4. Investigation of magnetically enhanced swelling behaviour of ...

    Indian Academy of Sciences (India)

    perties of nanoparticles affect their usability as a biomaterial in medicine pharmacy and veterinary practices. Swelling of native starch and iron oxide containing .... charge. This may lead to precipitation which could be dangerous if these particles are injected intravenously. Therefore, it is important to know the size of the ...

  5. synthesis, rheological behavior and swelling properties of ...

    African Journals Online (AJOL)

    Preferred Customer

    temperature and swelling environment has been observed to be dependent on both structural aspects of the polymers and ... CONH–) of PNIPAAm hydrate to form an expanded structure when the temperature is below. LCST. ... was carried in glass tubes of 10 mm inner diameter at room temperature for 2 h, using APS and.

  6. Unusual presentation of ulcerative postauricular swelling as ...

    African Journals Online (AJOL)

    The swelling became ulcerative and associated with progressive tinnitus and hoarseness of voice. The patient was investigated. Fine‑needle aspiration cytology suggested sebaceous cell carcinoma. Then excision biopsy was done, and histopathological examination of excised tissue confirmed the diagnosis. Extraorbital ...

  7. PREVENTION OF PHOSPHATE - INDUCED MITOCHONDRIAL SWELLING

    Science.gov (United States)

    Kroll, Arnold J.; Kuwabara, Toichiro

    1962-01-01

    The prevention of phosphate-induced mitochondrial swelling in the whole retina of the rabbit was studied with the electron microscope. It was found that a mixture of ATP, Mg++, and bovine serum albumin protected the mitochondria in vitro. This finding confirmed the results obtained spectrophotometrically with isolated rat liver mitochondria by Lehninger. PMID:13927020

  8. The extrudate swell of HDPE: Rheological effects

    Science.gov (United States)

    Konaganti, Vinod Kumar; Ansari, Mahmoud; Mitsoulis, Evan; Hatzikiriakos, Savvas G.

    2017-05-01

    The extrudate swell of an industrial grade high molecular weight high-density polyethylene (HDPE) in capillary dies is studied experimentally and numerically using the integral K-BKZ constitutive model. The non-linear viscoelastic flow properties of the polymer resin are studied for a broad range of large step shear strains and high shear rates using the cone partitioned plate (CPP) geometry of the stress/strain controlled rotational rheometer. This allowed the determination of the rheological parameters accurately, in particular the damping function, which is proven to be the most important in simulating transient flows such as extrudate swell. A series of simulations performed using the integral K-BKZ Wagner model with different values of the Wagner exponent n, ranging from n=0.15 to 0.5, demonstrates that the extrudate swell predictions are extremely sensitive to the Wagner damping function exponent. Using the correct n-value resulted in extrudate swell predictions that are in excellent agreement with experimental measurements.

  9. Magnetic relaxation--coal swelling, extraction, pore size

    Energy Technology Data Exchange (ETDEWEB)

    Doetschman, D.C.

    1991-01-01

    The grant activities during this period fall into four categories: (1) Completion of preparatory work, (2) Procedure refinement and actual preparation of whole coal, coal residue, coal extract and swelled coal samples for NMR studies, (3) Related studies of coal photolysis that employ materials from preliminary extractions and that examine the u.v.-visible and mass spectra of the extracts and (4) Continued investigations of the pulsed EPR characteristics of the whole coal samples that were prepared in the first quarter of the grant.

  10. Swell Propagation over Indian Ocean Region

    Directory of Open Access Journals (Sweden)

    Suchandra A. Bhowmick

    2011-06-01

    Full Text Available Swells are the ocean surface gravity waves that have propagated out of their generating fetch to the distant coasts without significant attenuation. Therefore they contain a clear signature of the nature and intensity of wind at the generation location. This makes them a precursor to various atmospheric phenomena like distant storms, tropical cyclones, or even large scale sea breeze like monsoon. Since they are not affected by wind once they propagate out of their generating region, they cannot be described by regional wave models forced by local winds. However, their prediction is important, in particular, for ship routing and off shore structure designing. In the present work, the propagation of swell waves from the Southern Ocean and southern Indian Ocean to the central and northern Indian Ocean has been studied. For this purpose a spectral ocean Wave Model (WAM has been used to simulate significant wave height for 13 years from 1993–2005 using NCEP blended winds at a horizontal spatial resolution of 1° × 1°. It has been observed that Indian Ocean, with average wave height of approximately 2–3 m during July, is mostly dominated by swell waves generated predominantly under the extreme windy conditions prevailing over the Southern Ocean and southern Indian Ocean. In fact the swell waves reaching the Indian Ocean in early or mid May carry unique signatures of monsoon arriving over the Indian Subcontinent. Pre-monsoon month of April contains low swell waves ranging from 0.5–1 m. The amplitudes subsequently increase to approximately 1.5–2 meters around 7–15 days prior to the arrival of monsoon over the Indian Subcontinent. This embedded signature may be utilized as one of the important oceanographic precursor to the monsoon onset over the Indian Ocean.

  11. Swelling and tensile properties of neutron-irradiated vanadium alloys

    International Nuclear Information System (INIS)

    Loomis, B.A.; Smith, D.L.

    1990-07-01

    Vanadium-base alloys are candidates for use as structural material in magnetic fusion reactors. In comparison to other candidate structural materials (e.g., Type 316 stainless and HT-9 ferritic steels), vanadium-base alloys such as V-15Cr-5Ti and V-20Ti have intrinsically lower long-term neutron activation, neutron irradiation after-heat, biological hazard potential, and neutron-induced helium and hydrogen transmutation rates. Moreover, vanadium-base alloys can withstand a higher surface-heat, flux than steels because of their lower thermal stress factor. In addition to having these favorable neutronic and physical properties, a candidate alloy for use as structural material in a fusion reactor must have dimensional stability, i.e., swelling resistance, and resistance to embrittlement during the reactor lifetime at a level of structural strength commensurate with the reactor operating temperature and structural loads. In this paper, we present experimental results on the swelling and tensile properties of several vanadium-base alloys after irradiation at 420, 520, and 600 degree C to neutron fluences ranging from 0.3 to 1.9 x 10 27 neutrons/m 2 (17 to 114 atom displacements per atom [dpa])

  12. Development of advanced austenitic stainless steels resistant to void swelling under irradiation

    International Nuclear Information System (INIS)

    Rouxel, Baptiste

    2016-01-01

    In the framework of studies about Sodium Fast Reactors (SFR) of generation IV, the CEA is developing new austenitic steel grades for the fuel cladding. These steels demonstrate very good mechanical properties but their use is limited because of the void swelling under irradiation. Beyond a high irradiation dose, cavities appear in the alloys and weaken the material. The reference material in France is a 15Cr/15Ni steel, named AIM1, stabilized with titanium. This study try to understand the role played by various chemical elements and microstructural parameters on the formation of the cavities under irradiation, and contribute to the development of a new grade AIM2 more resistant to swelling. In an analytical approach, model materials were elaborated with various chemical compositions and microstructures. Ten grades were cast with chemical variations in Ti, Nb, Ni and P. Four specific microstructures for each alloy highlighted the effect of dislocations, solutes or nano-precipitates on the void swelling. These materials were characterized using TEM and SANS, before irradiation with Fe 2+ (2 MeV) ions in the order to simulate the damages caused by neutrons. Comparing the irradiated microstructures, it is demonstrated that the solutes have a dominating effect on the formation of cavities. Specifically titanium in solid solution reduces the swelling whereas niobium does not show this effect. Finally, a matrix enriched by 15% to 25% of nickel is still favorable to limit swelling in these advanced austenitic stainless steels. (author) [fr

  13. Irradiation-induced swelling in solution annealed AISI 316

    International Nuclear Information System (INIS)

    Bates, J.F.; Weiner, R.A.; Korenko, M.K.

    1978-11-01

    Swelling in solution annealed AISI 316 has been empirically described as a function of temperature and fluence. An equation, suitable for design purposes, has been developed from an analysis of all of the available swelling data and complementary investigations. The equation is bi-linear in nature and incorporates different temperature dependent functions for both the maximum linear swelling rate parameter and the incubation parameter. The equation describing the swelling rate parameter differs from previous functions in that a constant swelling rate occurs from around 450 to 500 0 C followed by a peak swelling rate at around 570 0 C

  14. Controlling morphology in swelling-induced wrinkled surfaces

    Science.gov (United States)

    Breid, Derek Ronald

    Wrinkles represent a pathway towards the spontaneous generation of ordered surface microstructure for applications in numerous fields. Examples of highly complex ordered wrinkle structures abound in Nature, but the ability to harness this potential for advanced material applications remains limited. This work focuses on understanding the relationship between the patterns on a wrinkled surface and the experimental conditions under which they form. Because wrinkles form in response to applied stresses, particular attention is given to the nature of the stresses in a wrinkling surface. The fundamental insight gained was then utilized to account for observed wrinkle formation phenomena within more complex geometric and kinetic settings. In order to carefully control and measure the applied stresses on a wrinkling film, a swelling-based system was developed using poly(dimethylsiloxane) (PDMS), surface-oxidized with a UV-ozone treatment. The swelling of the oxidized surface upon exposure to an ethanol vapor atmosphere was characterized using beam-bending experiments, allowing quantitative measurements of the applied stress. The wrinkle morphologies were characterized as a function of the overstress, defined as the ratio of the applied swelling stress to the critical buckling stress of the material. A transition in the dominant morphology of the wrinkled surfaces from dimple patterns to ridge patterns was observed at an overstress value of ˜2. The pattern dependence of wrinkles on the ratio of the principal stresses was examined by fabricating samples with a gradient prestress. When swollen, these samples exhibited a smooth morphological transition from non-equibiaxial to equibiaxial patterns, with prestrains as low as 2.5% exhibiting non-equibiaxial characteristics. This transition was seen both in samples with low and high overstresses. To explore the impact of these stress states in more complex geometries, wrinkling hemispherical surfaces with radii of curvature

  15. Swelling of EPDM Rubbers for Oil-Well Applications as Influenced by Medium Composition and Temperature II: experimental part

    NARCIS (Netherlands)

    Zielińska, M.; Seyger, R.; Dierkes, Wilma K.; Bielinski, D.; Noordermeer, Jacobus W.M.

    2016-01-01

    The first part of the paper describes the mechanism of interactions between hydrocarbon solvents and vulcanized rubber (representing crosslinked network structure). The problem has been discussed from the point of view of thermodynamic principles of swelling, temperature and material factors

  16. Synthesis, Characterization and Swelling Characteristics of Graft Copolymerized Isotactic Polypropylene Film

    Directory of Open Access Journals (Sweden)

    Teena Sehgal

    2010-01-01

    Full Text Available Grafted membranes were prepared through chemical graft copolymerization of methyl methacrylate (MMA onto isotactic polypropylene film (IPP. The IPP films were grafted with MMA molecules resulting in IPP-g-MMA grafts using benzoyl peroxide as an initiator in an inert nitrogen atmosphere. Using this method, the degree of grafting and morphology could be controlled through the variation of reaction parameters such as initiator concentration, monomer concentration, reaction time, and the reaction temperature. Optimum conditions pertaining to maximum percentage of grafting (%G were evaluated as a function of these parameters. Maximum percentage of grafting (50% was obtained at [BPO]=0.03 M, [MMA]=10% V/V, and [Reaction Temperature] = 70∘C in a [Reaction time] of 120 minutes. IPP-g-MMA films were investigated for their swelling behavior. Water-swelling analysis of IPP-g-MMA was carried out as a function of different percentage of grafting, temperatures, and time. Maximum swelling percentage of IPP-g-MMA (92% was observed in 8 hours at 60∘C. The evidence of grafting was carried out by Fourier transform spectroscopy (FTIR, atomic force microscopy (AFM, and scanning electron microscopy (SEM before and after grafting, respectively. The swelling pattern was characterized by two distinct stages, an initial diffusion-controlled fast swelling, followed by a subsequent slower process controlled by the relaxation of polymer fragments. Swelling chrematistics of IPP-g-MMA make it a potentially useful material.

  17. How Much Do Ultrathin Polymers with Intrinsic Microporosity Swell in Liquids?

    KAUST Repository

    Ogieglo, Wojciech

    2016-09-13

    As synthetic membrane materials, polymers with intrinsic microporosity (PIMs) have demonstrated unprecedented permeation and molecular-separation properties. Here, we report the swelling characteristics of submicron-thick supported films of spirobisindane-based PIMs, PIM-1 and PIM-6FDA-OH, for six organic solvents and water using in situ spectroscopic ellipsometry. Surprisingly, PIMs swell significantly in most organic solvents, with swelling factors (SF = h/h) as high as 2.5. This leads to the loss of the ultrarigid character of the polymer and produces equilibrated liquid-like swollen films. Filling of the excess frozen-in fractional free volume with liquid was discovered next to swelling-induced polymer matrix dilation. Water hardly swells the polymer matrix, but it penetrates into the intrinsic microporous structure. This study is the first to provide fundamental swelling data for PIMs, leading to better comprehension of their permeation properties. Such an understanding is indispensable for applications such as solvent filtration, natural-gas separation, and ion retention in flow batteries.

  18. Mechanisms of amorphization-induced swelling in silicon carbide: the molecular dynamics answer

    International Nuclear Information System (INIS)

    Bertolus, M.; Ribeiro, F.; Defranceschi, M.

    2007-01-01

    We present here the continuation of an investigation of the irradiation-induced swelling of SiC using classical molecular dynamics (CMD) simulations. Heavy ion irradiation has been assumed to affect the material in two successive steps (a) creation of local atomic disorder, modeled by the introduction of extended amorphous areas with various sizes and shapes in a crystalline SiC sample at constant volume (b) induced swelling, determined through relaxation using Molecular Dynamics at constant pressure. This swelling has been computed as a function of the amorphous fraction introduced. Two different definitions of the amorphous fraction were introduced to enable meaningful comparisons of our calculations with experiments and elastic modeling. One definition based on the displacements relative to the ideal lattice positions was used to compare the CMD results with data from experiments combining ion implantations and channeled Rutherford Backscattering analyses. A second definition based on atomic coordination was used to compare the CMD results to those yielded by a simplified elastic model. The results obtained are as follows. On the one hand, comparison of the swelling obtained as a function of the lattice amorphous fraction with the experimental results shows that the melting-quench amorphization simulates the best the irradiation-induced amorphization observed experimentally. This is consistent with the thermal spike phenomenon taking place during ion implantation. On the other hand, disorder analysis at the atomic scale confirms the elastic behavior of the amorphization-induced swelling, in agreement with the comparison with the results of an elastic model. First, no major structural reconstruction occurs during relaxation or annealing. Second, the systems with the most disordered and constrained amorphous area undergo the largest swelling. This means that the disorder and the constraints of the bulk amorphous area are the driving forces for the swelling

  19. Capillary rise and swelling in cellulose sponges

    Science.gov (United States)

    Ha, Jonghyun; Kim, Jungchul; Kim, Ho-Young

    2015-11-01

    A cellulose sponge, which is a mundane example of a porous hydrophilic structure, can absorb and hold a significant amount of liquid. We present the results of experimental and theoretical investigation of the dynamics of the capillary imbibition of various aqueous solutions in the sponge that swells at the same time. We find that the rate of water rise against the resistance caused by gravitational and viscous effects deviates from Washburn's rule beyond a certain threshold height. We rationalize the novel power law of the rise height versus time by combining Darcy's law with hygroscopic swelling equation and also predict the threshold height. The scaling law constructed through this work agrees well with the experimental results, shedding light on the physics of capillary flow in deforming porous media.

  20. [Extensive swelling reaction after a pentavalent vaccination].

    Science.gov (United States)

    Gébus, M; Barbier, C; Bost-Bru, C; Michard-Lenoir, A P; Plantaz, D

    2015-09-01

    Injection site reactions (ISRs) are quite common side effects defined by a local adverse drug reaction directly caused by a vaccine. Twenty-four hours after an intramuscular injection (in the deltoid muscle) of the diphtheria, tetanus, acellular pertussis, inactivated poliomyelitis, Haemophilus influenza type b (DTPCa-Hib) combined vaccine, a 3-year-old boy developed fever. A few hours later, local redness and swelling appeared at the injection site, with rapid extension to the entire limb, it was pain-free, and no other clinical anomalies were present. The patient received intravenous antibiotics for suspected cellulitis. The progression was favorable in 12h (apyrexia and decreased limb swelling), allowing the intravenous antibiotic treatment to be discontinued. Since the child was in excellent general health and recovery was fast, an ISR was diagnosed. Extensive limb swelling is frequent, mostly after the fourth dose of DTPCa-Hib. Deltoid muscle injection of DTP vaccine increases the risk of ISR compared to injection in the thigh, before the age of 3 years. The introduction of acellular pertussis vaccine decreased the risk of general side effects but may increase the risk of ISR. These reactions disappear with symptomatic treatment and do not contraindicate the product. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  1. Mechanisms affecting swelling in alloys with precipitates

    International Nuclear Information System (INIS)

    Mansur, L.K.; Haynes, M.R.; Lee, E.H.

    1980-01-01

    In alloys under irradiation many mechanisms exist that couple phase instability to cavity swelling. These are compounded with the more familiar mechanisms associated with point defect behavior and the evolution of microstructure. The mechanisms may be classified according to three modes of operation. Some affect cavity swelling directly by cavity-precipitate particle association, others operate indirectly by precipitate-induced changes in sinks other than cavities and finally there are mechanisms that are mediated by precipitate-induced changes in the host matrix. The physics of one mechanism of each type is developed in detail and the results compared where possible to experimental measurements. In particular, we develop the theory necessary to treat the effects on swelling of precipitation-induced changes in overall sink density; precipitation-induced changes in point defect trapping by solute depletion and creation of precipitate particle-matrix interfacial trap sites; and preciwill come from waste wood available locally requiring minimal energy for recovery and transportation to the site. The applicant is strongly considering the use of a solar preheating unit anium southward as well as to deeper dened al half-lives with experimental ones, over a range of 24 orders of magnitude was obtained. This is a strong argument that the alpha decay could be considered a fission process with very high mass asymmetry and charge density asymmetry

  2. Effect of crosslinker on the swelling and adsorption properties of ...

    Indian Academy of Sciences (India)

    methacryloyloxy) ethyl] trimethylammonium chloride have been prepared by free radical solution polymerization with different crosslinkers. They were subjected to repeated cycles of swelling and de-swelling in deionized water and NaCl solution.

  3. Role of Defects in Swelling and Creep of Irradiated SiC

    Energy Technology Data Exchange (ETDEWEB)

    Szlufarska, Izabela [Univ. of Wisconsin, Madison, WI (United States); Voyles, Paul [Univ. of Wisconsin, Madison, WI (United States); Sridharan, Kumar [Univ. of Wisconsin, Madison, WI (United States); Katoh, Yutai [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-01-16

    Silicon carbide is a promising cladding material because of its high strength and relatively good corrosion resistance. However, SiC is brittle and therefore SiC-based components need to be carefully designed to avoid cracking and failure by fracture. In design of SiC-based composites for nuclear reactor applications it is essential to take into account how mechanical properties are affected by radiation and temperature, or in other words, what strains and stresses develop in this material due to environmental conditions. While thermal strains in SiC can be predicted using classical theories, radiation-induced strains are much less understood. In particular, it is critical to correctly account for radiation swelling and radiation creep, which contribute significantly to dimensional instability of SiC under radiation. Swelling typically increases logarithmically with radiation dose and saturates at relatively low doses (damage levels of a few dpa). Consequently, swelling-induced stresses are likely to develop within a few months of operation of a reactor. Radiation-induced volume swelling in SiC can be as high as 2%, which is significantly higher than the cracking strain of 0.1% in SiC. Swelling-induced strains will lead to enormous stresses and fracture, unless these stresses can be relaxed via some other mechanism. An effective way to achieve stress relaxation is via radiation creep. Although it has been hypothesized that both radiation swelling and radiation creep are driven by formation of defect clusters, existing models for swelling and creep in SiC are limited by the lack of understanding of specific defects that form due to radiation in the range of temperatures relevant to fuel cladding in light water reactors (LWRs) (<1000°C). For example, defects that can be detected with traditional transmission electron microscopy (TEM) techniques account only for 10-45% of the swelling measured in irradiated SiC. Here, we have undertaken an integrated experimental and

  4. [A boy with a swelling under his right jaw].

    Science.gov (United States)

    Gremmer, Jessica E; Moes, A R Roelof

    2015-01-01

    A 12-year-old boy presented with a painful swelling under his right jaw. Cat scratch disease was confirmed serologically. Two months later the swelling had increased in size and had become red. There was obvious fluctuation, which indicated abscess formation. After incision and drainage of the abscess, the swelling resolved within two weeks.

  5. Factors which determine the swelling rate of austenitic stainless steels

    International Nuclear Information System (INIS)

    Garner, F.A.; Wolfer, W.G.

    1983-01-01

    Once void nucleation subsides, the swelling rate of many austenitic alloys becomes rather insensitive to variables that control the transient regime of swelling. Models are presented which describe the roles of nickel, chromium and silicon in void nucleation. The relative insensitivity of steady-state swelling to temperature, displacement rate and composition is also discussed

  6. He+ and H+ microbeam damage, swelling and annealing in diamonds

    International Nuclear Information System (INIS)

    Dooley, S.P.; Jamieson, D.N.; Prawer, S.

    1992-01-01

    The effects of scanned 2 MeV He + and 1.4 MeV H + microbeam irradiation on unimplanted and P implanted diamond are discussed. Although diamond was found to be resistant to lattice defect production, it was found to swell very rapidly in comparison with other materials, giving rise to serious swelling induced dechanneling at scan edges at relatively low doses (10 17 /cm 2 for 2 MeV He + ). Microbeams annealed the damage due to a 1.5 μm deep Phosphorus implantation at a dose of 10 15 P + /cm 2 . The implantation damage was reduced at a dose of (1.6 x 10 17 /cm 2 ) by up to 21 % for 2 MeV He + irradiation, up to 16% for high flux 1.4 MeV H + irradiation and 12% for low flux H + irradiation. For the choice of analysis beam, all these beam effects were found to be most significant for He + microbeams, so H + microbeams should be used for analysis of diamond unless high depth resolution is required. 13 refs., 10 figs

  7. Rock swelling during shaft construction caused by low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Demich, L.M.; Kozel, A.M.; Kostyrkin, A.A.; Koldobskii, Yu.A.

    1981-03-01

    This paper Discusses effects of rock swelling during shaft sinking using rock freezing. A coal mine shaft is sunk up to a depth of 314.8m. The average temperature of sedimentary rocks amounts to 30.5 C. A zone 17.5m in diameter is frozen by 63 freezing pipes. Temperature of freezing mixture amounts to minus 30 C. Location of boreholes and control boreholes as well as fluctuating dimensions of frozen zone are shown in 2 schemes. Rock swelling caused by expansion of water in pores and fissures up to a depth of 135 m is analyzed. Liner deformations reach 30 mm. The most intensive deformations occur in aleurolite zone, with moisture content up to 22.4%. The maximum load which acts on liners amounts to 2,773 kPa. Deformed liners are reinforced by roof bolting and wire net. Negative effects of deformation of monolithic concrete are stressed. It is suggested that when using rock freezing in shaft sinking in porous rock bearing strata rock expansion caused by low temperature should be considered in calculations. Using yielding materials in zones exposed to the highest deformations is recommended. (3 refs.) (In Russian)

  8. Void swelling behaviour of austenitic stainless steel during electron irradiation

    International Nuclear Information System (INIS)

    Sheng Zhongqi; Xiao Hong; Peng Feng; Ti Zhongxin

    1994-04-01

    The irradiation swelling behaviour of 00Cr17Ni14Mo2 austenitic stainless steel (AISI 316L) was investigated by means of high voltage electron microscope. Results showed that in solution annealed condition almost no swelling incubation period existed, and the swelling shifted from the transition period to the steady-state one when the displacement damage was around 40 dpa. In cold rolled condition there was evidently incubation period, and when the displacement damage was up to 84 dpa the swelling still remained in the transition period. The average size and density of voids in both conditions were measured, and the factors, which influenced the void swelling, were discussed. (3 figs.)

  9. Overnight corneal swelling with high and low powered silicone hydrogel lenses.

    Science.gov (United States)

    Moezzi, Amir M; Fonn, Desmond; Varikooty, Jalaiah; Simpson, Trefford L

    2015-01-01

    To compare central corneal swelling after eight hours of sleep in eyes wearing four different silicone hydrogel lenses with three different powers. Twenty-nine neophyte subjects wore lotrafilcon A (Dk, 140), balafilcon A (Dk, 91), galyfilcon A (Dk, 60) and senofilcon A (Dk, 103) lenses in powers -3.00, -10.00 and +6.00 D on separate nights, in random order, and on one eye only. The contra-lateral eye (no lens) served as the control. Central corneal thickness was measured using a digital optical pachometer before lens insertion and immediately after lens removal on waking. For the +6.00 D and -10.00 D, lotrafilcon A induced the least swelling and galyfilcon A the most. The +6.00 D power, averaged across lens materials, induced significantly greater central swelling than the -10.00 and -3.00 D (Re-ANOVA, p<0.001), (7.7±2.9% vs. 6.8±2.8% and 6.5±2.5% respectively) but there was no difference between -10.00 and -3.00 D. Averaged for power, lotrafilcon A induced the least (6.2±2.8%) and galyfilcon A the most (7.6±3.0%) swelling at the center (Re-ANOVA, p<0.001). Central corneal swelling with +6.00 D was significantly greater than -10.00 D lens power despite similar levels of average lens transmissibility of these two lens powers. The differences in corneal swelling of the lens wearing eyes are consistent with the differences in oxygen transmission of the silicone hydrogel lenses. In silicone hydrogel lenses central corneal swelling is mainly driven by central lens oxygen transmissibility. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  10. Swelling induced by alpha decay in monazite and zirconolite ceramics: A XRD and TEM comparative study

    Science.gov (United States)

    Deschanels, X.; Seydoux-Guillaume, A. M.; Magnin, V.; Mesbah, A.; Tribet, M.; Moloney, M. P.; Serruys, Y.; Peuget, S.

    2014-05-01

    Zirconolite and monazite matrices are potential ceramics for the containment of actinides (Np, Cm, Am, Pu) which are produced over the reprocessing of spent nuclear fuel. Actinides decay mainly through the emission of alpha particles, which in turn causes most ceramics to undergo structural and textural changes (amorphization and/or swelling). In order to study the effects of alpha decays on the above mentioned ceramics two parallel approaches were set up. The first involved the use of an external irradiation source, Au, which allowed the deposited recoil energy to be simulated. The second was based on short-lived actinide doping with 238Pu, (i.e. an internal source), via the incorporation of plutonium oxide into both the monazite and zirconolite structures during synthesis. In both types of irradiation experiments, the zirconolite samples became amorphous at room temperature with damage close to 0.3 dpa; corresponding to a critical dose of 4 × 1018 α g-1 (i.e. ∼1.3 × 1021 keV cm-3). Both zirconolite samples also showed the same degree of macroscopic swelling at saturation (∼6%), with ballistic processes being the predominant damaging effect. In the case of the monazite however, the macroscopic swelling and amorphization were dependent on the nature of the irradiation. Externally, (Au), irradiated samples became amorphous while also demonstrating a saturation swelling of up to 8%. In contrast to this, the swelling of the 238Pu doped samples was much smaller at ∼1%. Also, unlike the externally (Au) irradiated monazite these 238Pu doped samples remained crystalline up to 7.5 × 1018 α g-1 (0.8 dpa). XRD, TEM and swelling measurements were used to fully characterize and interpret this behavior. The low swelling and the conservation of the crystalline state of 238Pu doped monazite samples indicates that alpha annealing took place within this material.

  11. Thermal Expansion and Swelling of Cured Epoxy Resin Used in Graphite/Epoxy Composite

    Science.gov (United States)

    Adamson, M. J.

    1979-01-01

    The thermal expansion and swelling of resin material as influenced by variations in temperature during moisture absorption is discussed. Comparison measurements using composites constructed of graphite fibers and each of two epoxy resin matrices are included. Polymer theory relative to these findings is discussed and modifications are proposed.

  12. Influence of swelling on tensile properties of 316 Ti cold-hammered hexagonal tubes

    International Nuclear Information System (INIS)

    Fissolo, A.; Levy, V.; Cauvin, R.; Hugot, J.P.

    1988-01-01

    The main limitations of fast neutron reactor hexagonal tubes are generally deformation and irradiation embrittlement. If many data were published on deformations generated by swelling or irradiation creep, there are only few data on the mechanical behavior of the irradiated material. In this paper we give results of tensile testing on 316 Ti samples irradiated at high dose in Phenix reactor [fr

  13. Alteration of non-swelling clay minerals and magadiite by acid activation

    NARCIS (Netherlands)

    Steudel, A.; Batenburg, L.F.; Fischer, H.R.; Weidler, P.G.; Emmerich, K.

    2009-01-01

    The bulk material of three kaolins, a sepiolite, an illite and one magadiite were treated with 1, 5 and 10 M H2SO4 at 80 °C for several hours. The alteration of the non-swelling clay mineral structures was controlled by the individual character of each mineral (chemical composition and initial

  14. Critical parameters controlling irradiation swelling in beryllium

    International Nuclear Information System (INIS)

    Dubinko, V.I.

    1995-01-01

    Radiation effects in beryllium can hardly be explained within a framework of the conventional theory based on the bias concept due to elastic interaction difference (EID) between vacancies and self-interstitial atoms (SIAs) since beryllium belongs to hexagonal close-packed metals where diffusion has been shown to be anisotropic. Diffusional anisotropy difference (DAD) between point defects changes the cavity bias for their absorption and leads to dependence of the dislocation bias on the distribution of dislocations over crystallographic directions. On the other hand, the elastic interaction between point defects and cavities gives rise to the size and gas pressure dependencies of the cavity bias, resulting in new critical quantities for bubble-void transition effects at low temperature irradiation. In the present paper, we develop the concept of the critical parameters controlling irradiation swelling with account of both DAD and EID, and take care of thermal effects as well since they are of major importance for beryllium which has an anomalously low self-diffusion activation energy. Experimental data on beryllium swelling are analyzed on the basis of the present theory. (orig.)

  15. Swelling of Brazilian organoclays in some solvents with application in the petroleum industry

    International Nuclear Information System (INIS)

    Queiroz, M.B.; Rodrigues, S.C.G.; Laborde, H.M.; Rodrigues, M.G.F.

    2009-01-01

    The organophilic clays can be synthesized by the addition of quaternary ammonium salts in aqueous dispersions of sodium smectite clays, which are highly hydrophobic. The objective was to prepare and characterize an organophilic clay used in the adsorption of organic solvents. Preparation of organophilic clay was made up from the Brasgel PA clay in nature and the quaternary ammonium salt. The materials were characterized by X-ray diffraction and Foster's swelling. The results obtained by the Xray diffraction technique of confirmed the acquisition of organophilic clay Brasgel and the Foster's swelling showed the hydrophobic characteristic. (author)

  16. Water Vapor Sensors Based on the Swelling of Relief Gelatin Gratings

    Directory of Open Access Journals (Sweden)

    Sergio Calixto

    2015-01-01

    Full Text Available We report on a novel device to measure relative humidity. The sensor is based on surface diffraction gratings made of gelatin. This material swells and shrinks according to the content of water vapor in air. By sending a light beam to the grating, diffracted orders appear. Due to the gelatin swelling or shrinking, first order intensity changes according to the relative humidity. Calibration curves relating intensity versus relative humidity have been found. The fabrication process of diffraction gratings and the testing of the prototype sensing devices are described.

  17. A contribution to the better understanding of swelling in soils and soft rocks

    Directory of Open Access Journals (Sweden)

    Ana Petkovšek

    2010-12-01

    Full Text Available Swelling and shrinkage of sediments rich with clay belong to geologically conditioned risk factors. Economicloss as the consequence of volume changes in the geological catchment area of buildings and infrastructuralobjects is immense. Untimely detected swelling causes higher prices and unnecessary delays during the construction.In those cases when deep cuts and underground spaces are used as intervention into highly preconsolidatedsoils and soft rock with clay contents, failures of embankments and improperly designed supporting measures dueto swelling are not infrequent. Also periodic appearance of landslides at certain areas can be the consequence ofswelling. Some countries, such as the USA, introduced the guidelines and standards for the detection, assessmentand handling with swellable geological materials decades ago. Due to some other more urgent geologically conditionedrisks, such as landslides, earthquakes and constructions on soft ground, in Slovenia the development ofknowledge in the area of swelling soils was several years behind the knowledge in the rest of the world. With theconstruction of the Slovenian-Hungarian railway connection after 1998, motorways and the introduction of newknowledge about soil suction, also Slovenian experts were introduced to a different dimension of the problem ofswelling soils, as well as some important experiences were learned and new possibilities for the investigation andunderstanding of volume behaviour of swelling soils were opened. This is especially important for the predictedweather extremes, as only adequate knowledge will allow us to adequately explain any new phenomena in theground and prepare appropriate protection.

  18. Molecular accessibility in solvent swelled coals. Quarterly report, [April--June 1993

    Energy Technology Data Exchange (ETDEWEB)

    Kispert, L.D.

    1993-08-01

    The effect of weathering (oxidation and dehydration upon exposure to air) on the molecular accessibility of potential catalysts was studied by the EPR spin probe technique. Fresh samples of all 8 APCS coals were exposed to air for periods up to 36 days. Weathering produced significant effects on the retention of spin probes in most of the APCS coals under 91 % carbon (dmmf). It was determined that the lower ranked coal (Beulah Zap and Wyodak) under went a structural collapse which precluded retention of even spin probe VIII. However, medium ranked coals exhibited improved retention upon weathering when swelled in toluene. Swelling with pyridine opened up small pores for 81--86% carbon which is not observed for swelling with toluene. Changes in coal structure were successfully followed by the EPR spin probe method. A detailed analysis of the data collected from the swelling of coals oxidized in a moisture free environment was completed to differentiate between weathering and oxidation. Eight vacuum dried APCS coals were oxidized in an enclosed, pure oxygen, moisture free environment, and the effects of oxidation alone on coal structure were studied by the intercalation of EPR spin probes. The data shows a factor of 5 increase in spin probe retention for some coals oxidized in O{sub 2} versus air., suggesting a large increase in oxidized material. Particular care was taken during the swelling procedures to avoid exposure of the coal samples to air or moisture. EPR spectra were then obtained for these 300 samples.

  19. Extracranial soft-tissue swelling: a normal postmortem radiographic finding or a sign of trauma?

    Energy Technology Data Exchange (ETDEWEB)

    Strouse, P.J. [Section of Pediatric Radiology, University of Michigan Medical Center, Ann Arbor (United States); Caplan, M. [Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan (United States); Owings, C.L. [Department of Pediatrics and Communicable Diseases, C. S. Mott Children`s Hospital, Ann Arbor, Michigan (United States)

    1998-08-01

    Objective. To determine if extracranial soft-tissue swelling is an expected postmortem finding or a sign of trauma. Materials and methods. Extracranial soft-tissue thickness was measured at 5 standardized locations on postmortem skull films obtained of 18 infants with no evidence of trauma on autopsy. The same measurements were performed on the skull films of 100 living children, all less than 3 years old and without clinical history of trauma. Results. Extracranial soft tissues measured only slightly greater in the postmortem group than on films of living children; however, the difference did achieve statistical significance. Conclusion. Minimal extracranial soft-tissue swelling is a normal finding on a postmortem skeletal survey. The presence of substantial or asymmetric extracranial soft-tissue swelling should be viewed with suspicion for trauma. (orig.) With 2 tabs., 5 refs.

  20. Microscale patterning of thermoplastic polymer surfaces by selective solvent swelling.

    Science.gov (United States)

    Rahmanian, Omid; Chen, Chien-Fu; DeVoe, Don L

    2012-09-04

    A new method for the fabrication of microscale features in thermoplastic substrates is presented. Unlike traditional thermoplastic microfabrication techniques, in which bulk polymer is displaced from the substrate by machining or embossing, a unique process termed orogenic microfabrication has been developed in which selected regions of a thermoplastic surface are raised from the substrate by an irreversible solvent swelling mechanism. The orogenic technique allows thermoplastic surfaces to be patterned using a variety of masking methods, resulting in three-dimensional features that would be difficult to achieve through traditional microfabrication methods. Using cyclic olefin copolymer as a model thermoplastic material, several variations of this process are described to realize growth heights ranging from several nanometers to tens of micrometers, with patterning techniques include direct photoresist masking, patterned UV/ozone surface passivation, elastomeric stamping, and noncontact spotting. Orogenic microfabrication is also demonstrated by direct inkjet printing as a facile photolithography-free masking method for rapid desktop thermoplastic microfabrication.

  1. Magnetic resonance imaging of clays: swelling, sedimentation, dissolution

    Science.gov (United States)

    Dvinskikh, Sergey; Furo, Istvan

    2010-05-01

    measure of clay distribution in extended samples during different physical processes such as swelling, dissolution, and sedimentation on the time scale from minutes to years [1-3]. To characterize the state of colloids that form after/during clay swelling the water self-diffusion coefficient was measured on a spatially resolved manner. Both natural clays and purified and ion-exchanged montmorillonite clays were investigated. The primary variables were clay composition and water ionic strength. These results have a significant impact for engineering barriers for storage of spent nuclear fuel where clay erosion by low salinity water must be addressed. Presented methods were developed under the motivation of using bentonite clays as a buffer medium to build in-ground barriers for the encapsulation of radioactive waste. Nevertheless, the same approaches can be found suitable in other applications in soil and environmental science to study other types of materials as they swell, dissolve, erode, or sediment. Acknowledgements: This work has been supported by the Swedish Nuclear Fuel and Waste Management Co (SKB) and the Swedish Research Council VR. [1] N. Nestle, T. Baumann, R. Niessner, Magnetic resonance imaging in environmental science. Environ. Sci. Techn. 36 154A (2002). [2] S. V. Dvinskikh, K. Szutkowski, I. Furó. MRI profiles over a very wide concentration ranges: application to swelling of a bentonite clay. J. Magn. Reson. 198 146 (2009). [3] S. V. Dvinskikh, I. Furó. Magnetic resonance imaging and nuclear magnetic resonance investigations of bentonite systems. Technical Report, TR-09-27, SKB (2009), www.skb.se.

  2. Numerical Simulation Of The Treatment Of Soil Swelling Using Grid Geocell Columns

    Science.gov (United States)

    Fattah, Mohammed Y.; Al-Omari, Raid R.; Ali, Haifaa A.

    2015-06-01

    In this paper, a method for the treatment of the swelling of expansive soil is numerically simulated. The method is simply based on the embedment of a geogrid (or a geomesh) in the soil. The geogrid is extended continuously inside the volume of the soil where the swell is needed to be controlled and orientated towards the direction of the swell. Soils with different swelling potentials are employed: bentonite base-Na and bentonite base-Ca samples in addition to kaolinite mixed with bentonite. A numerical analysis was carried out by the finite element method to study the swelling soil's behavior and investigate the distribution of the stresses and pore water pressures around the geocells beneath the shallow footings. The ABAQUS computer program was used as a finite element tool, and the soil is represented by the modified Drucker-Prager/cap model. The geogrid surrounding the geocell is assumed to be a linear elastic material throughout the analysis. The soil properties used in the modeling were experimentally obtained. It is concluded that the degree of saturation and the matric suction (the negative pore water pressure) decrease as the angle of friction of the geocell column material increases due to the activity of the sand fill in the dissipation of the pore water pressure and the acceleration of the drainage through its function as a drain. When the plasticity index and the active depth (the active zone is considered to be equal to the overall depth of the clay model) increase, the axial movement (swelling movement) and matric suction, as a result of the increase in the axial forces, vary between this maximum value at the top of the layer and the minimum value in the last third of the active depth and then return to a consolidation at the end of the depth layer.

  3. Angiosarcoma Presenting with Minor Erythema and Swelling

    Directory of Open Access Journals (Sweden)

    Catherine A. Cox

    2013-04-01

    Full Text Available A 76-year-old man presented with slowly progressive swelling in his forehead and left upper eyelid over the course of three months. CT scanning showed non-specific enhancement of subcutaneous tissues, suggesting a low-grade cellulitis. Poor response to treatment prompted an MRI, which revealed the presence of a soft tissue lesion. Biopsy of this lesion was positive for angiosarcoma. The patient underwent chemotherapy and radiation, but unfortunately succumbed to his malignancy eight months later. This case illustrates a rare example of facial/periorbital angiosarcoma, a benign-appearing but aggressive tumor associated with a high incidence of mortality. A review of the literature and current treatment options are discussed.

  4. Midface swelling reveals nasofrontal dermal sinus

    International Nuclear Information System (INIS)

    Houneida, Zaghouani Ben Alaya; Manel, Limeme; Latifa, Harzallah; Habib, Amara; Dejla, Bakir; Chekib, Kraiem

    2012-01-01

    Nasofrontal dermal sinuses are very rare and generally occur in children. This congenital malformation can be revealed by midface swelling, which can be complicated by local infection or neuromeningitis. Such complications make the dermal sinus a life-threatening disease. Two cases of nasofrontal dermal sinuses are reported in this work. The first case is an 11-month-old girl who presented with left orbitonasal soft tissue swelling accompanied by inflammation. Physical examination found fever, left orbitonasal thickening, and a puncture hole letting out pus. Computed tomography revealed microabscesses located at the left orbitonasal soft tissues, a frontal bone defect, and an intracranial cyst. Magnetic resonance imaging showed the transosseous tract between the glabella and the brain and affirmed the epidermoid nature of the intracranial cyst. The second case is a 7-year-old girl who presented with a nasofrontal non-progressive mass that intermittently secreted a yellow liquid through an external orifice located at the glabella. MRI revealed a cystic mass located in the deep layer of the glabellar skin related to an epidermoid cyst with a nasofrontal dermal sinus tract. In both cases, surgical excision was performed, and pathological confirmation was made for the diagnoses of dermal sinuses. The postoperative course was favorable. Through these cases, the authors stress the role of imaging methods in confirming the diagnosis and looking for associated cysts (dermoid and epidermoid) to improve recognition of this rare disease. Knowledge of the typical clinical presentations, imaging manifestations, and most common sites of occurrence of this malformation are needed to formulate a differential diagnosis.

  5. Swelling behavior of titanium-modified AISI 316 alloys

    International Nuclear Information System (INIS)

    Garner, F.A.; Brager, H.R.; Puigh, R.J.

    1984-01-01

    It appears that titanium additions to stainless steels covering a wide compositional range around the specifications of AISI 316 result only in an increased delay period before neutron-induced void swelling proceeds. Once swelling is initiated the post transient behavior of both annealed and cold-worked titanium-modified steels is quite consistent with that of AISI 316, approaching a relatively temperature-independent swelling rate of approx. 1% per dpa

  6. Study of the Effect of Swelling on Irradiation Assisted Stress Corrosion Cracking

    Energy Technology Data Exchange (ETDEWEB)

    Teysseyre, Sebastien Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    This report describes the methodology used to study the effect of swelling on the crack growth rate of an irradiation-assisted stress corrosion crack that is propagating in highly irradiated stainless steel 304 material irradiated to 33 dpa in the Experimental Breeder Reactor-II. The material selection, specimens design, experimental apparatus and processes are described. The results of the current test are presented.

  7. Microstructure and anisotropic swelling behaviour of compacted bentonite/sand mixture

    Directory of Open Access Journals (Sweden)

    Simona Saba

    2014-04-01

    Full Text Available Pre-compacted elements (disks, torus of bentonite/sand mixture are candidate materials for sealing plugs of radioactive waste disposal. Choice of this material is mainly based on its swelling capacity allowing all gaps in the system to be sealed, and on its low permeability. When emplaced in the gallery, these elements will start to absorb water from the host rock and swell. Thereby, a swelling pressure will develop in the radial direction against the host rock and in the axial direction against the support structure. In this work, the swelling pressure of a small scale compacted disk of bentonite and sand was experimentally studied in both radial and axial directions. Different swelling kinetics were identified for different dry densities and along different directions. As a rule, the swelling pressure starts increasing quickly, reaches a peak value, decreases a little and finally stabilises. For some dry densities, higher peaks were observed in the radial direction than in the axial direction. The presence of peaks is related to the microstructure change and to the collapse of macro-pores. In parallel to the mechanical tests, microstructure investigation at the sample scale was conducted using microfocus X-ray computed tomography (μCT. Image observation showed a denser structure in the centre and a looser one in the border, which was also confirmed by image analysis. This structure heterogeneity in the radial direction and the occurrence of macro-pores close to the radial boundary of the sample can explain the large peaks observed in the radial swelling pressure evolution. Another interesting result is the higher anisotropy found at lower bentonite dry densities, which was also analysed by means of μCT observation of a sample at low bentonite dry density after the end of test. It was found that the macro-pores, especially those between sand grains, were not filled by swelled bentonite, which preserved the anisotropic microstructure caused by

  8. Swelling, Functionalization, and Structural Changes of the Nanoporous Layered Silicates AMH-3 and MCM-22

    KAUST Repository

    Kim, Wun-gwi

    2011-06-21

    Nanoporous layered silicate materials contain 2D-planar sheets of nanoscopic thickness and ordered porous structure. In comparison to porous 3D-framework materials such as zeolites, they have advantages such as significantly increased surface area and decreased diffusion limitations because the layers can potentially be exfoliated or intercalated into polymers to form nanocomposite materials. These properties are particularly interesting for applications as materials for enhancing molecular selectivity and throughput in composite membranes. In this report, the swelling and surface modification chemistry of two attractive nanoporous layered silicate materials, AMH-3 and MCM-22, were studied. We first describe a method, using long-chain diamines instead of monoamines, for swelling of AMH-3 while preserving its pore structure to a greater extent during the swelling process. Then, we describe a stepwise functionalization method for functionalizing the layer surfaces of AMH-3 and MCM-22 via silane condensation reactions. The covalently attached hydrocarbon chain molecules increased the hydrophobicity of AMH-3 and MCM-22 layer surfaces and therefore allow the possibility of effectively dispersing these materials in polymer matrices for thin film/membrane applications. © 2011 American Chemical Society.

  9. Study on the saturating and swelling behavior of an engineering bentonite barrier using a test model

    International Nuclear Information System (INIS)

    Nakajima, Makoto; Kobayashi, Ichizo; Toida, Masaru; Fujisaki, Katsutoshi

    2007-01-01

    The conceptual design of a disposal facility with additional buffer depth for radioactive waste is mainly constituted from the multi-barrier system that is constructed around the waste form so that it prevents radionuclide transfer to the biosphere. The engineered bentonite barrier is one of the elements of the multi-barrier system and is constructed with homogeneous bentonite-containing material compacted to a high density so that there are no voids. Due to the swelling characteristics of the bentonite material, the self-sealing function which is an important function of the bentonite barrier can work, but at the same time it mechanically affects the neighboring structures. Therefore, an experimental study was implemented in order to evaluate the mechanical effect of the bentonite swelling behavior throughout the construction, emplacement operations and closure re-saturation phase. In this article, the results of swelling tests to obtain the mechanical properties of the bentonite and three types of test model experiments performed for the event observations in the different saturation processes are described. As a result, the effects of a seepage pattern of ground water and a variation in the density produced by construction on the swelling pressure distribution of the bentonite barrier could be reproduced and validated. It is thought that they will be important events when ground water permeates the bentonite layer of a multiple barrier system. (author)

  10. Swelling behaviour of stones and its interest in conservation. An appraisal

    Directory of Open Access Journals (Sweden)

    Delgado Rodrigues, J.

    2001-12-01

    Full Text Available Swelling can be defined as the volume increase experienced by any solid body when wetted. Many lithotypes (carbonate rocks, sandstones, igneous rocks have expansive components in their composition; anhydrite and clay minerals are the two best-known expansive components in stone materials. Swelling strain can be easily quantified and swelling pressure determination is accessible in many geotechnical laboratories. This paper deals with the decay of stone due to swelling of clays and discusses the ways to take the swelling behaviour into account when the assessment of stone durability is concerned. It analyses the role of swelling in stone conservation and reviews some cases where this decay mechanism has a relevant role, explicit or implicitly.

    La expansibilidad puede ser definida como el incremento de volumen que un cuerpo sólido experimenta cuando es humedecido. Muchos tipos litológicos (rocas carbonatadas, areniscas, rocas ígneas tienen componentes expansivos en su composición; la anhidrita y los minerales arcillosos son los dos componentes expansivos más conocidos. La expansibilidad puede ser medida con facilidad y la determinación de la presión de hinchamiento se puede efectuar en muchos laboratorios de geotecnia. Este trabajo trata del problema de la degradación de los materiales rocosos debida a la expansión de las arcillas y discute las formas de tenerla en cuenta cuando interesa evaluar la durabilidad de esos materiales. Se analiza el papel de la expansibilidad en la conservación de la piedra y se hace una revisión de algunos casos en los que la degradación por expansión tiene un papel relevante, explícito o implícito.

  11. Prediction of Swelling Behavior of Addis Ababa Expansive Soil ...

    African Journals Online (AJOL)

    In this study a simple hyperbolic mathematical model is used to predict the swelling behavior of an expansive soil from Addis Ababa. The main parameters that are needed to run the model are the applied pressure and initial dry density. The other parameters of the model including the initial slope of the swell-time curve, the ...

  12. Neurofibromas as bilateral cystic chest wall swellings. | Ugare ...

    African Journals Online (AJOL)

    A 35 year old male farmer presented with soft bilateral posterior chest wall swellings. He had no similar swellings elsewhere. There were no associated symptoms, except cosmetic deformity and discomfort when he lies on his back. A clinical diagnosis of posterior chest wall lipomata was made. However at surgery, the two ...

  13. Ocean swell within the kinetic equation for water waves

    Directory of Open Access Journals (Sweden)

    S. I. Badulin

    2017-06-01

    Full Text Available Results of extensive simulations of swell evolution within the duration-limited setup for the kinetic Hasselmann equation for long durations of up to 2  ×  106 s are presented. Basic solutions of the theory of weak turbulence, the so-called Kolmogorov–Zakharov solutions, are shown to be relevant to the results of the simulations. Features of self-similarity of wave spectra are detailed and their impact on methods of ocean swell monitoring is discussed. Essential drop in wave energy (wave height due to wave–wave interactions is found at the initial stages of swell evolution (on the order of 1000 km for typical parameters of the ocean swell. At longer times, wave–wave interactions are responsible for a universal angular distribution of wave spectra in a wide range of initial conditions. Weak power-law attenuation of swell within the Hasselmann equation is not consistent with results of ocean swell tracking from satellite altimetry and SAR (synthetic aperture radar data. At the same time, the relatively fast weakening of wave–wave interactions makes the swell evolution sensitive to other effects. In particular, as shown, coupling with locally generated wind waves can force the swell to grow in relatively light winds.

  14. Thermal effects on granules and direct determination of swelling ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... DEA. UAA. Abidjan. Côte d'Ivoire, pp. 25-28. Larrigue S, Alvarez G, Cuvelier G, Flick D (2008). Swelling kinetics of waxy maize and starches at high temperatures and heating rates. Carbohydr. Polym. 73: 148-155. Leach HW, MC Cowen LD, Schoch JJ (1959). Structure of the starch granule swelling and ...

  15. Periorbital swelling in emergency room: Get your eyes in

    Directory of Open Access Journals (Sweden)

    SenthilKumaran S

    2009-01-01

    Full Text Available Facial swelling and eye pain are very common patient complaints in Emergency Departments. Clinical evidence and investigations play a crucial role in making the correct diagnosis which impacts the final disposition and management of the patient. We present a case of a patient who presented with facial swelling and headache.

  16. Isolated Actinomycotic Swelling in Right Upper Cervical Region.

    Science.gov (United States)

    Agrawal, Pankaj S; Bhargavan, P V; Mampilly, Neena

    2015-12-01

    Cervicofacial actinomycosis is today a rare disease in our country. Isolated neck swelling due to actinomycosis is extremely rare. A case of 52 year old man with an isolated neck swelling due to actinomycosis without any discharging sinus is reported here. © Journal of the Association of Physicians of India 2011.

  17. Effect of Recrystallization on Gas Bubble Swelling in UMo Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Shenyang; Lavender, Curt A.; Joshi, Vineet V.

    2017-07-31

    Recrystallization plays an important role in swelling kinetics of irradiated metallic nuclear fuels. This talk will present a three-dimensional microstructure-dependent swelling model by integrating the evolution of intra-and inter- granular gas bubbles, dislocation loop density, and recrystallization.

  18. Inguinoscrotal and inguinolabial swelling in infancy: Role of ...

    African Journals Online (AJOL)

    ... have chronic and 3 acute inguinolabial swelling. Conclusion: Color Doppler ultrasonography is an accurate, safe and readily available imaging modality which can be used to identify different etiologies of inguinoscrotal and inguinolabial swelling in infants. KEYWORDS: Pediatric; Scrotum; Hydrocele; Hernia; Ultrasound ...

  19. Geomechanical characterisation of unsaturated Kunigel V1 bentonite: swelling and shear strength

    International Nuclear Information System (INIS)

    Yamamoto, S.; Shimura, T.; Asano, H.; Namiki, K.; Romero, E.; Kato, S.

    2012-01-01

    Document available in extended abstract form only. The development and validation of hydro-geomechanical models for bentonite buffer are one of the important subjects to appropriately evaluate long term behaviour of EBS in radioactive waste disposal. The Barcelona Basic Model (BBM), which is one extension of the modified Cam- Clay model for unsaturated and expansive soil, has been developed and widely applied to several hydro-geomechanical problems by using the coupled THM code, Code-Bright. Some advantages of the model are that hydro-geomechanical characteristics of buffer materials under saturated and partially saturated conditions are taken into account as well as the swelling characteristics due to wetting. Applicability of the BBM to consolidation and swelling behaviour of unsaturated bentonite has already been confirmed. In this study swelling characteristics of unsaturated bentonite are further discussed based on results from controlled-suction odometer tests, and in addition shear strength depending on matric suction is discussed based on controlled-suction triaxial compression tests. Swelling tests of compacted bentonite (Kunigel V1, initial dry density: 1.0 Mg/m 3 ) under constant confined vertical net stresses (20 and 100 kPa) were performed by using controlled-suction odometer cells. Matrice suction was stepwise reduced from 500 kPa to 0 kPa by 100 kPa. It is found that swelling is more dominant in latter step of the suction change (i.e., closer steps to saturation), especially the step from 100 kPa to 0 kPa. Swelling due to wetting, i.e. decrease in matric suction is defined in the BBM. Controlled-suction triaxial compression tests of compacted bentonite (Kunigel V1, initial dry density: 1.36 Mg/m 3 ) under both constant matric suctions (0, 300, and 500 kPa) and constant confined lateral net stresses were performed to study dependency of shear strength on matric suction. It is found that the apparent cohesion linearly increases with increase in matric

  20. Swelling behavior of PEMFC during conditioning

    Directory of Open Access Journals (Sweden)

    J. Parrondo

    2007-09-01

    Full Text Available Polymeric cation exchange membranes (PEMFC are used in fuel cell technology. These membranes act as a physical barrier between anode and cathode, but diffusion through the membrane should allow protons to be carried from anode to cathode at a rate sufficient to supply energy requirements. They avoid any direct reaction of oxygen and hydrogen that would diminish fuel cell efficiency. Membranes have to be conditioned before use. This conditioning step changes membrane counterions and modifies their water content, which has an effect on their diffusion coefficients. In order to analyse and quantify the effect of conditioning techniques on membrane performance various experiments with Nafion 117 cation exchange membranes were carried out. Membranes were conditioned using various methods to change the charged cation in the membrane. The reactives used were ultrapure water, nitric acid, hydrochloric acid, hydrogen peroxide, sodium chloride, potassium chloride and ethylene glycol, all at room temperature. Some conditioning methods were carried out using solvents heated to 100 ºC. Water content was indirectly monitored by measuring membrane swelling. Results show that membrane conditioning with strong acids followed by treatment with water increases membrane water content by about 5%. Using high-temperature treatment the water content also increases. Water uptake or release from membranes is analysed in terms of water activity.

  1. Odontogenic facial swelling of unknown origin.

    Science.gov (United States)

    Ranjitkar, S; Cheung, W; Yong, R; Deverell, J; Packianathan, M; Hall, C

    2015-12-01

    Current radiography techniques have limitations in detecting subtle odontogenic anomalies or defects that can lead to dentoalveolar and facial infections. This report examines the application of micro-CT imaging on two extracted teeth to enable detailed visualization of subtle odontogenic defects that had given rise to facial swelling. Two extracted non-carious mandibular left primary canine teeth (73) associated with odontogenic infections were selected from two patients, and an intact contralateral tooth (83) from one of the patients was used as a control. All three teeth were subjected to three-dimensional micro-CT imaging at a resolution of 20 μm. Tooth 73 from the first case displayed dentine pores (channels) that established communication between the pulp chamber and the exposed dentine surface. In comparison, tooth 73 from the second case had a major vertical crack extending from the external enamel surface into the pulp chamber. The control tooth did not display any anomalies or major cracks. The scope of micro-CT imaging can be extended from current in vitro applications to establish post-extraction diagnosis of subtle odontogenic defects, in a manner similar to deriving histopathological diagnoses in extracted teeth. Ongoing technological advancements hold the promise for more widespread translatory applications. © 2015 Australian Dental Association.

  2. Thyroid swellings in the art of the Italian Renaissance.

    Science.gov (United States)

    Sterpetti, Antonio V; De Toma, Giorgio; De Cesare, Alessandro

    2015-09-01

    Thyroid swellings in the art of the Italian Renaissance are sporadically reported in the medical literature. Six hundred paintings and sculptures from the Italian Renaissance, randomly selected, were analyzed to determine the prevalence of personages with thyroid swellings and its meaning. The prevalence of personages with thyroid swellings in the art of Italian Renaissance is much higher than previously thought. This phenomenon was probably secondary to iodine deficiency. The presence of personages with thyroid swelling was related to specific meanings the artists wanted to show in their works. Even if the function and the role of the thyroid were discovered only after thyroidectomy was started to be performed, at the beginning of the 19th century, artists of the Italian Renaissance had the intuition that thyroid swellings were related to specific psychological conditions. Artistic intuition and sensibility often comes before scientific demonstration, and it should be a guide for science development. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Swelling and outgassing of heavily-irradiated lithium hydride

    International Nuclear Information System (INIS)

    Souers, P.C.; Ackerman, F.J.; Biel, T.J.; Bigwood, J.; Brite, V.; Christensen, L.D.; Folkers, C.L.; Gede, V.; Griffith, C.M.; Huss, E.B.; Lindahl, R.; McCreary, T.; Otsuki, H.H.; Pond, R.L.; Snider, G.D.; Stanhope, C.; Stump, R.K.; Vanderhoofven, F.; Tsugawa, R.T.; Anderson, J.L.; Carstens, D.W.H.; Drumhiller, W.L.; Lewis, W.B.; Nasise, J.E.; Pretzel, F.E.; Szklarz, E.G.; Vier, D.T.; Bowman, R.C. Jr.; Attalla, A.

    1988-01-01

    Twenty-two years worth of data on lithium deuteride-tritide (Li(D, T)) from three national laboratories is presented. The percent linear swelling and the outgassing of hydrogen isotopes and 3 He for samples stored at 243 to 438 K are presented in summary tables. In some cases, up to a full half-life of tritium (12 years) has been spent in the study. Initial tritium concentrations range from 2 to 98 at%. The precision of the swelling is considered, and the evidence is ambiguous as to whether temperature cycling and handling affects swelling. The early outgassing is all hydrogen, but it turns to helium at long lines. The outgassing levels out for each sample but the amount outgassed varies wildly from sample to sample. At linear swellings beyond 11%, behavior becomes erratic. A maximum linear swelling of 23% is seen for one sample at 5000 days. (orig.)

  4. Swelling in light water reactor internal components: Insights from computational modeling

    Energy Technology Data Exchange (ETDEWEB)

    Stoller, Roger E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Barashev, Alexander V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Golubov, Stanislav I. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-08-01

    A modern cluster dynamics model has been used to investigate the materials and irradiation parameters that control microstructural evolution under the relatively low-temperature exposure conditions that are representative of the operating environment for in-core light water reactor components. The focus is on components fabricated from austenitic stainless steel. The model accounts for the synergistic interaction between radiation-produced vacancies and the helium that is produced by nuclear transmutation reactions. Cavity nucleation rates are shown to be relatively high in this temperature regime (275 to 325°C), but are sensitive to assumptions about the fine scale microstructure produced under low-temperature irradiation. The cavity nucleation rates observed run counter to the expectation that void swelling would not occur under these conditions. This expectation was based on previous research on void swelling in austenitic steels in fast reactors. This misleading impression arose primarily from an absence of relevant data. The results of the computational modeling are generally consistent with recent data obtained by examining ex-service components. However, it has been shown that the sensitivity of the model s predictions of low-temperature swelling behavior to assumptions about the primary damage source term and specification of the mean-field sink strengths is somewhat greater that that observed at higher temperatures. Further assessment of the mathematical model is underway to meet the long-term objective of this research, which is to provide a predictive model of void swelling at relevant lifetime exposures to support extended reactor operations.

  5. Water Absorption and Thickness Swelling Behavior of Polypropylene Reinforced with Hybrid Recycled Newspaper and Glass Fiber

    Science.gov (United States)

    Shakeri, Alireza; Ghasemian, Ali

    2010-04-01

    This study aims to investigate the moisture absorption of recycled newspaper fiber and recycled newspaper-glass fiber hybrid reinforced polypropylene composites to study their suitability in outdoor applications. In this work composite materials were made from E-glass fiber (G), recycled newspaper (NP) and polypropylene (PP), by using internal mixing and hot-pressing molding. Long-term water absorption (WA) and thickness swelling (TS) kinetics of the composites was investigated with water immersion. It was found that the WA and TS increase with NP content in composite and water immersion time before an equilibrium condition was reached. Composites made from the NP show comparable results as those made of the hybrid fiber. The results suggest that the water absorption and thickness swelling composite decrease with increasing glass fiber contents in hybrid fiber composite. It is interesting to find that the WA and TS can be reduced significantly with incorporation of a coupling agent (maleated polypropylene) in the composite formulation. Further studies were conducted to model the water diffusion and thickness swelling of the composites. Diffusion coefficients and swelling rate parameters in the models were obtained by fitting the model predictions with the experimental data.

  6. Effects of metallurgical variables on swelling of modified 316 and higher Ni austenitic stainless steels

    International Nuclear Information System (INIS)

    Shibahara, Itaru; Akasaka, Naoaki; Onose, Shoji

    1996-01-01

    The effects of solute elements and cold-work on swelling in modified 316 and higher Ni advanced austenitic stainless steels developed for FBR core material were investigated together with the posted model alloys. The Si, P, B, Ti, Nb modified and cold-worked steels exhibited an improved swelling resistance. In the temperature range between 400 and 500 C, the swelling was suppressed significantly by an addition of 0.8 wt% Si. The beneficial effect of Si appears to be reduced in the steels without Ti and Nb tending to form γ' precipitates. In the temperature range between 500 and 600 C, a needle-like phosphide precipitates played an important role in suppressing void growth. Additions of Ti and/or Nb were found to stabilize the phosphide phase and extended the swelling incubation period. In the improved austenitic steels, the synergistic effect of cold-working and P, B, Ti, Nb additions act beneficially to stabilize the dislocation structure and to form finely dispersed precipitates during irradiation

  7. Swelling pressure and hydration behavior of porcine corneal stroma.

    Science.gov (United States)

    Hatami-Marbini, Hamed; Etebu, Ebitimi; Rahimi, Abdolrasol

    2013-11-01

    The aim of this study was to characterize swelling pressure-thickness, swelling pressure-hydration and hydration-thickness relations of porcine cornea. Mechanical compression tests and free swelling experiments were performed on porcine cornea. A rheometer (DHR-2, TA Instruments) with a thermally controlled fluid chamber filled with 0.9% NaCl solution was used to measure the equilibrium swelling pressure of (n = 17) corneal stromal specimens. The samples were compressed incrementally and their swelling pressure-thickness relations were obtained. In parallel to this investigation, a transient digital imaging microscope (H800-CL, American Scope Inc.), a USB autofocus camera (UM05, ViTiny), and a precision weighing scale (AGZN100, Torbal) were simultaneously used to measure the weight-thickness relation of (n = 8) corneal specimens. This experimental study gave the thickness-hydration relationship required for expressing swelling pressure measurements as a function of hydration. At the in vivo 666 ± 68 µm central corneal thickness, an average swelling pressure of 52 ± 13 mmHg and hydration of 3.36 ± 0.25 mg H2O/mg dry tissue were found. The swelling pressure was reported as functions of both tissue thickness and hydration. The average fixed charge density of ρF/F ~ 42.8 mM and dry density of 1.47±0.15 g/cm3 were found. The thickness-hydration relationship was only linear when the tissue thickness was within the range of physiological thickness. Overall, the physiological hydration and swelling pressure of the porcine cornea were within the same range of those reported previously for other mammalian corneas such as steers, rabbits and humans. Nevertheless, the thickness-hydration behavior of the porcine cornea was only similar to that of the human cornea.

  8. Swelling of Polymeric Membranes in Room Temperature Ionic Liquids

    Czech Academy of Sciences Publication Activity Database

    Izák, Pavel; Hovorka, Š.; Bartovský, T.; Bartovská, L.; Crespo, J.G.

    2007-01-01

    Roč. 296, 1-2 (2007), s. 131-138 ISSN 0376-7388 Grant - others:FCT(PT) SFRH/BPD/9470/2002; FCT(PT) POCTI/EQU/35437/2000 Institutional research plan: CEZ:AV0Z40720504 Source of funding: R - rámcový projekt EK ; R - rámcový projekt EK Keywords : membrane swelling * swelling measurement * anisotropic swelling Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.432, year: 2007

  9. Seasonality of Ankle Swelling: Population Symptom Reporting Using Google Trends.

    Science.gov (United States)

    Liu, Fangwei; Allan, G Michael; Korownyk, Christina; Kolber, Michael; Flook, Nigel; Sternberg, Harvey; Garrison, Scott

    2016-07-01

    In our experience, complaints of ankle swelling are more common in summer, typically from patients with no obvious cardiovascular disease. Surprisingly, this observation has never been reported. To objectively establish this phenomenon, we sought evidence of seasonality in the public's Internet searches for ankle swelling. Our data, obtained from Google Trends, consisted of all related Google searches in the United States from January 4, 2004, to January 26, 2016. Consistent with our expectations and confirmed by similar data for Australia, Internet searches for information on ankle swelling are highly seasonal (highest in midsummer), with seasonality explaining 86% of search volume variability. © 2016 Annals of Family Medicine, Inc.

  10. Controlling the swelling and wettability of weak polyelectrolyte brushes

    Science.gov (United States)

    Gurtowski, Richard; Jing, Benxin; Zhu, Elaine

    2011-03-01

    Weak polyelectrolytes (PE) of tunable ionization shows great potential as ``smart'' polymer materials for diverse applications from drug delivery to energy storage. However, the conformational dynamics of surfaced-tethered weak PE chains remain inadequately understood due to the complexity of their dynamic charge states in response to solvation and surface immobilization conditions. In this work, we investigate the wetting and swelling characteristics of poly(2-vinyl pyridine) (P2VP) brushes grafted to a gold substrate by AFM and water contact angle measurements. We observe the collapse of P2VP brushes, accompanied with increased surface hydrophobicity, as increasing solution pH across a critical transition pH, which is considerably lower than the pKa of free P2VP chains in bulk solution. Surprisingly, the broadness of the transition pH range shows a strong dependence with brush thickness, but not grafting density, suggesting a distribution of chain ionization along grafted P2VP brushes. We further manipulate P2VP brush structures by applying ac-electric fields across the brushes to make tunable and switchable polymer surfaces.

  11. Coupled thermo-hydro-chemical models of swelling bentonites

    Science.gov (United States)

    Samper, Javier; Mon, Alba; Zheng, Liange; Montenegro, Luis; Naves, Acacia; Pisani, Bruno

    2014-05-01

    The disposal of radioactive waste in deep geological repositories is based on the multibarrier concept of retention of the waste by a combination of engineered and geological barriers. The engineered barrier system (EBS) includes the solid conditioned waste-form, the waste container, the buffer made of materials such as clay, grout or crushed rock that separate the waste package from the host rock and the tunnel linings and supports. The geological barrier supports the engineered system and provides stability over the long term during which time radioactive decay reduces the levels of radioactivity. The strong interplays among thermal (T), hydrodynamic (H), mechanical (M) and chemical (C) processes during the hydration, thermal and solute transport stages of the engineered barrier system (EBS) of a radioactive waste repository call for coupled THMC models for the metallic overpack, the unsaturated compacted bentonite and the concrete liner. Conceptual and numerical coupled THMC models of the EBS have been developed, which have been implemented in INVERSE-FADES-CORE. Chemical reactions are coupled to the hydrodynamic processes through chemical osmosis (C-H coupling) while bentonite swelling affects solute transport via changes in bentonite porosity changes (M-H coupling). Here we present THMC models of heating and hydration laboratory experiments performed by CIEMAT (Madrid, Spain) on compacted FEBEX bentonite and numerical models for the long-term evolution of the EBS for 1 Ma. The changes in porosity caused by swelling are more important than those produced by the chemical reactions during the early evolution of the EBS (t iron mineral phases (corrosion products) released by the corrosion of the carbon steel canister; and 2) The hyper alkaline plume produced by the concrete liner. Numerical results show that the pH in the bentonite pore water in the presence of a concrete liner can vary from neutral to up to 13 over a time scale of 1 Ma although dissolution of

  12. Cinnamon polyphenols attenuate cell swelling and mitochondrial dysfunction following oxygen-glucose deprivation in glial cells

    Science.gov (United States)

    Astrocyte swelling is an integral component of cytotoxic brain edema in ischemic injury. While mechanisms underlying astrocyte swelling are likely multifactorial, oxidative stress and mitochondrial dysfunction are hypothesized to contribute to such swelling. We investigated the protective effects of...

  13. The Effect of Elasticityon the Extrudate Swell of Molten Polymers

    Science.gov (United States)

    Hatzikiriakos, Savvas; Konaganti, Vinod Kumar; UBC Team

    2016-11-01

    The extrudate swell of an industrial grade high molecular weight high-density polyethylene (HDPE) in capillary dies is studied using the integral K-BKZ constitutive model. The non-linear viscoelastic flow properties of the polymer resin are studied for a broad range of large step shear strains and high shear rates using the cone partitioned plate (CPP) geometry of the stress/strain controlled rotational rheometer. This allowed the determination of the rheological parameters accurately, in particular the damping function, which is proven to be the most important in simulating transient flows such as extrudate swell. A series of simulations performed using the integral K-BKZ Wagner model with different values of the Wagner exponent n, ranging from n = 0.15 to 0.5, demonstrates that the extrudate swell predictions are extremely sensitive to the Wagner damping function exponent. Using the correct n - value resulted in extrudate swell predictions that are in excellent agreement with experimental measurements. .

  14. Effect of crosslinker on the swelling and adsorption properties of ...

    Indian Academy of Sciences (India)

    016-1220-0. Effect of crosslinker on the swelling and adsorption properties of cationic superabsorbent. TARUN SHARMA and GIRIDHAR MADRAS. ∗. Department of Chemical Engineering, Indian Institute of Science, Bangalore 560 012, India.

  15. Swelling in simple ferritic alloys irradiated to high fluence

    International Nuclear Information System (INIS)

    Gelles, D.S.; Meinecke, R.L.

    1984-01-01

    A series of Fe-Cr-C-Mo simple alloys has been measured for density change as a function of irradiation in EBR-II over the temperature range 400 to 650 0 C to fluences as high as 2.13 x 10 23 n/cm 2 (E > 0.1 MeV) or 105 dpa. The highest swelling was found in a Fe-12Cr binary alloy, 4.72 percent, after 1.87 x 10 23 n/cm 2 or 95 dpa at 425 0 C, which corresponds to a swelling rate of 0.06%/dpa. This peak swelling rate value can be used to define swelling predictions for commercial ferritic alloys to 40 MWy/m 2

  16. Postoperative Submandibular Gland Swelling following Craniotomy under General Anesthesia

    Directory of Open Access Journals (Sweden)

    Haruka Nakanishi

    2015-01-01

    Full Text Available Objective. Reporting of a rare case of postoperative submandibular gland swelling following craniotomy. Case Report. A 33-year-old male underwent resection for a brain tumor under general anesthesia. The tumor was resected via a retrosigmoid suboccipital approach and the patient was placed in a lateral position with his face down and turned to the right. Slight swelling of the right submandibular gland was observed just after the surgery. Seven hours after surgery, edematous change around the submandibular gland worsened and he required emergent reintubation due to airway compromise. The cause of submandibular gland swelling seemed to be an obstruction of the salivary duct due to surgical positioning. Conclusion. Once submandibular swelling and edematous change around the submandibular gland occur, they can worsen and compromise the air way within several hours after operation. Adequate precaution must be taken for any predisposing skull-base surgery that requires strong cervical rotation and flexion.

  17. Journal of EEA, Vol. 30, 2013 PREDICTION OF SWELLING ...

    African Journals Online (AJOL)

    dell

    modeling, swelling potential, swelling pressure. INTRODUCTION. In the capital ... clay system is a function of the permeability of soil, hydraulic gradient ... 1.9. Sand content (grain size. 2mm to 5 m), %. 6.10. 3.8. 2.8. Silt content (grain size. 75 m to 2 m), %. 17.41. 17.56. 15.4. Clay content. (grain size <2 m). 76.49. 78.64. 81.8.

  18. Swelling behavior of manganese-bearing AISI 216 steel

    International Nuclear Information System (INIS)

    Gelles, D.S.; Garner, F.A.

    1984-01-01

    The inclusion of 8.5 wt % manganese in AISI 216 does not appear to alter the swelling behavior from that found to be typical of austenitic alloys with comparable levels of other austentite-stabilizing elements. The swelling in AISI 216 in EBR-II is quite insensitive to irradiation temperature in the range 400-650 0 C. Microscopy reveals that this may arise from the low level of precipitation that occurs in the alloy

  19. Lepromatous leprosy presenting as a swelling in the neck

    Directory of Open Access Journals (Sweden)

    Dogra Devraj

    1999-01-01

    Full Text Available A 25-year-old electrician presented with gradually, asymptomatic swelling on left of the neck since 2 years. The swelling which was initially diagnosed as cervical lymphadenitis by the internist represented the enlarged left great auricular nerve. Cutaneous examination revealed an ill-defined, hypoaesthetic macule with minimal atrophy on the pinna of the left ear. The histopathology of the nerve showed a lepromatous neuritis with bacteriological index (BI of 5+.

  20. Detailed analysis of uranium silicide dispersion fuel swelling

    International Nuclear Information System (INIS)

    Hofman, G.L.; Ryu, Woo-Seog.

    1989-01-01

    Swelling of U 3 Si and U 3 Si 2 is analyzed. The growth of fission gas bubbles appears to be affected by fission rate, fuel loading, and microstructural change taking place in the fuel compounds during irradiation. Several mechanisms are explored to explain the observations. The present work is aimed at a better understanding of the basic swelling phenomenon in order to accurately model irradiation behavior of uranium silicide disperson fuel. 5 refs., 10 figs

  1. Detailed analysis of uranium silicide dispersion fuel swelling

    International Nuclear Information System (INIS)

    Hofmann, G.L.; Ryu, Woo-Seog

    1991-01-01

    Swelling of U 3 Si and U 3 Si 2 is analyzed. The growth of fission gas bubbles appears to be affected by fission rate, fuel loading, and micro structural change taking place in the fuel compounds during irradiation. Several mechanisms are explored to explain the observations. The present work is aimed at a better understanding of the basic swelling phenomenon in order to accurately model irradiation behavior of uranium silicide dispersion fuel. (orig.)

  2. Swelling and infusion of tea in tea bags.

    Science.gov (United States)

    Yadav, Geeta U; Joshi, Bhushan S; Patwardhan, Ashwin W; Singh, Gurmeet

    2017-07-01

    The present study deals with swelling and infusion kinetics of tea granules in tea bags. The swelling and infusion kinetics of tea bags differing in tea loading and tea bag shapes were compared with loose tea. Increment in temperature and dipping frequency of tea bag in hot water increased the infusion kinetics of tea bags. Reduction in particle size enhanced the swelling and infusion kinetics of tea in a tea bag. The effects of tea particle size, tea bag dipping rate, loading of tea granules in tea bag and tea bag shapes on infusion kinetics were investigated. Increase in tea loading in tea bags resulted in reduced infusion kinetics. Double chambered tea bag showed the highest swelling (30%) and infusion kinetics (8.30% Gallic acid equivalence) while single chambered tea bags showed the lowest kinetics, amongst the various bags studied. The swelling and infusion kinetics of loose tea was always faster and higher than that of tea bags. It was found that overall effect of percentage filling of tea granules and height of tea bed in a tea bag affects tea infusion kinetics the most. Weibull model was found to be in good agreement with the swelling data.

  3. Electron microscopic observation of montmorillonite swelled by water with the aid of hydrophilic ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Chisato [Advanced Ceramics Research Center, Nagoya Institute of Technology, Honmachi 3-101-1, Tajimi, Gifu 507-0033 (Japan); Department of Pharmaceutical Engineering, School of Pharmacy, Aichi Gakuin University, Kusumoto 1-100, Chikusa, Nagoya, Aichi 464-8650 (Japan); Shirai, Takashi [Advanced Ceramics Research Center, Nagoya Institute of Technology, Honmachi 3-101-1, Tajimi, Gifu 507-0033 (Japan); Fuji, Masayoshi, E-mail: fuji@nitech.ac.jp [Advanced Ceramics Research Center, Nagoya Institute of Technology, Honmachi 3-101-1, Tajimi, Gifu 507-0033 (Japan)

    2013-09-16

    The morphology and structure of hydrous montmorillonite in different swelling condition have been observed with the aid of hydrophilic ionic liquid (IL; 1-Butyl-3-methylimidazolium Tetrafluoroborate) using electron microscope. The observation mechanism of hydrous montmorillonite with layer structure using IL was revealed by swelling behavior as measured by X-ray diffraction (XRD) and transmission electron microscopy (TEM) with selected area electron diffraction pattern (SAED). The morphology of hydrous montmorillonite containing a large amount of water was also successfully observed by field emission electron microscope (FE-SEM). In addition, the inductively coupled plasma (ICP) and thermogravimetric – differential thermal analysis (TG-DTA) results showed the ion-exchange behavior of hydrous montmorillonite during the IL treatment. The technique allowed the exact morphology to be observed of hydrated materials with layer structure in civil engineering, cosmetics, medical and agricultural fields. - Highlights: • Observation of two different conditions of hydrated montmorillonite was investigated. • The swelling structure by water molecules was characterized by TEM. • The observation mechanism of hydrous montmorillonite was revealed. • Ionic liquid is useful for characterization of hydrated materials with layer structure.

  4. Surface depression of glass and surface swelling of ceramics induced by ion implantation

    International Nuclear Information System (INIS)

    Ikeyama, Masami; Saitoh, Kazuo; Nakao, Setsuo; Niwa, Hiroaki; Tanemura, Seita; Miyagawa, Yoshiko; Miyagawa, Souji

    1994-01-01

    By the measurement of the change of the surface shapes of the glass and ceramics in which ion implantation was performed, it was clarified that glass surface was depressed, and ceramic surface swelled. These depression and swelling changed according to the kinds of ions, energy and the amount to be implanted and the temperature of samples. It became clear that the depression of glass surface was nearly proportional to the range of flight of the implanted ions, and the swelling of ceramic surface showed different state in the silicon nitride with strong covalent bond and the alumina and sapphire with strong ionic bond. For the improvement of the mechanical characteristics of solid materials such as hardness, strength, toughness, wear resistance, oxidation resistance and so on, attention has been paid to the surface reforming by high energy ion implantation at MeV level. The change of shapes of base materials due to ion implantation is not always negligible. The experiment was carried out on sintered silicon nitride and alumina, polished sapphire single crystals and quartz glass. The experimental method and the results are reported. (K.I.)

  5. Synovial hemangiohamartoma presenting as knee pain, swelling and a soft tissue mass: a case report

    Directory of Open Access Journals (Sweden)

    Senol Serkan

    2012-07-01

    Full Text Available Abstract Introduction We present a case of a patient with juxtaarticular hemangiohamartoma with a synovial extension associated with hemorrhagic synovitis and recurrent spontaneous hemarthrosis. Case presentation A 21-year-old Caucasian woman was admitted to our hospital complaining of pain and swelling at her knee for 6 months. In the magnetic resonance imaging, T2-weighted and fat-suppressed scans revealed a mass with high signal intensity just posterior to the patellar tendon. We performed an excisional biopsy of the mass through an anterior longitudinal incision. Excised material included arterial and venous vascular structures, which were found to be spread among the fat, connective and peripheral nerve tissues microscopically. Conclusion Although hemangiohamartomas are not true neoplasms, they may cause knee pain, swelling and hemarthrosis that warrant surgical resection. This lesion, although rare, should be considered in the differential diagnosis, especially in teenagers and young adults.

  6. Circumferential nonuniformity of cladding radiation swelling of fast reactor peripheral fuel elements

    International Nuclear Information System (INIS)

    Reutov, V.F.; Farkhutdinov, K.G.

    1977-01-01

    The results are presented of the investigation into the perimeter radiation swelling of Kh18N10T stainless steel cladding in different cross sections of a peripheral fuel element of the BR-5 reactor. The fluence on the cladding is 1.8-2.9 x 10 22 fast neutr/cm 2 , the operating temperatures in different parts of the fuel element being 430 deg to 585 deg C. There has been observed circumferential non-uniformity of the distribution, concentration, and of the total volume of radiation cavities, which is due to temperature non-uniformity along the cladding perimeter. It is shown that such non-uniformity of radiation swelling of the cladding material may result in bending of the peripheral fuel element with regard to the fuel assembly sheath walls

  7. Evaluation of stress-controlled coal swelling processes

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jishan; Chen, Zhongwei [Shool of Mechanical Engineering, The University of Western Australia, WA, 6009 (Australia); Elsworth, Derek [Department of Energy and Mineral Engineering, Penn State University, PA 16802-5000 (United States); Miao, Xiexing; Mao, Xianbiao [State Key Laboratory for Geomechanics and Underground Engineering, China University of Mining and Technology (China)

    2010-09-01

    Stress-controlled swelling tests are normally conducted in the laboratory to characterize the evolution of coal permeability under the influence of gas sorption. Typically reductions in permeability are observed from gas-sorption-induced swelling even where effective stresses remain constant. This behavior remains enigmatic as the permeability of the porous coal is determined by the effective stress only. When these observations were interpreted, a matchstick or cubic coal model was assumed. Under this assumption, matrix swelling would not affect coal permeability because of the complete separation between matrix blocks caused by through-going fractures. This is why current coal permeability models have little success in explaining this inconsistency. It is generally believed that the reason for the failure is the inconsistency between the experimental conditions and the model assumptions. However, in this paper, it is considered that the reason may be the internal actions between coal fractures and matrixes have not been taken into consideration. In this study, a model capable of replicating this apparently anomalous behavior is developed. We consider the interactions of the fractured coal mass where cleats do not create a full separation between adjacent matrix blocks but where solid rock bridges are present. We accommodate the role of swelling strains both over contact bridges that hold cleat faces apart but also over the non-contacting span between these bridges. The effects of swelling act competitively over these two components: increasing porosity and permeability due to swelling of the bridging contacts but reducing porosity and permeability due to the swelling of the intervening free-faces. Under these conditions, a new permeability model is formulated. The new model is the key cross link that couples the multiphysics of coal-gas interactions. The formulation and incorporation of this permeability model into the multiphysics simulation of coal

  8. Peritonsillar swelling is not always quinsy

    Directory of Open Access Journals (Sweden)

    Mohamad I

    2013-10-01

    Full Text Available Quinsy is a common encounter in family physician practice. It is defined as a collection of purulent material in the peritonsillar space, giving appearance of unilateral palatal bulge. Presenting symptoms include trismus, muffled voice, odynophagia, and ipsilateral otalgia. When the diagnostic needle aspiration reveals no pus, the diagnosis is changed into peritonsillar cellulitis or also known as perintonsillitis. Peritonsillitis is sufficiently treated with antibiotics unlike a quinsy which warrants surgical incision and drainage.

  9. Materials

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2009-02-01

    Full Text Available community. The construction industry is a significantly consumer of materials, using 50 per cent of all products produced globally. Building materials is any material which is used for a construction purpose. Many of these materials are sources from natural...

  10. Controlling the extrudate swell in melt extrusion additive manufacturing of 3D scaffolds: a designed experiment.

    Science.gov (United States)

    Yousefi, Azizeh-Mitra; Smucker, Byran; Naber, Alex; Wyrick, Cara; Shaw, Charles; Bennett, Katelyn; Szekely, Sarah; Focke, Carlie; Wood, Katherine A

    2018-02-01

    Tissue engineering using three-dimensional porous scaffolds has shown promise for the restoration of normal function in injured and diseased tissues and organs. Rigorous control over scaffold architecture in melt extrusion additive manufacturing is highly restricted mainly due to pronounced variations in the deposited strand diameter upon any variations in process conditions and polymer viscoelasticity. We have designed an I-optimal, split-plot experiment to study the extrudate swell in melt extrusion additive manufacturing and to control the scaffold architecture. The designed experiment was used to generate data to relate three responses (swell, density, and modulus) to a set of controllable factors (plotting needle diameter, temperature, pressure, and the dispensing speed). The fitted regression relationships were used to optimize the three responses simultaneously. The swell response was constrained to be close to 1 while maximizing the modulus and minimizing the density. Constraining the extrudate swell to 1 generates design-driven scaffolds, with strand diameters equal to the plotting needle diameter, and allows a greater control over scaffold pore size. Hence, the modulus of the scaffolds can be fully controlled by adjusting the in-plane distance between the deposited strands. To the extent of the model's validity, we can eliminate the effect of extrudate swell in designing these scaffolds, while targeting a range of porosity and modulus appropriate for bone tissue engineering. The result of this optimization was a predicted modulus of 14 MPa and a predicted density of 0.29 g/cm 3 (porosity ≈ 75%) using polycaprolactone as scaffold material. These predicted responses corresponded to factor levels of 0.6 μm for the plotting needle diameter, plotting pressure of 2.5 bar, melt temperature of 113.5 °C, and dispensing speed of 2 mm/s. The validation scaffold enabled us to quantify the percentage difference for the predictions, which was 9.5% for the

  11. Study of sorption and swelling on block coals

    Science.gov (United States)

    Qu, Shijie; Chen, Guoqing; Yang, Jianli; Shen, Wenzhong; Li, Yunmei; Niu, Hongxian; Busch, Andreas

    2013-04-01

    Reducing CO2 emission into atmosphere is very important for the mitigation of global climate change. Many processes have been proposed for this purpose, including CO2 sequestration in un-minable coalbeds and enhance coalbed methane production (CO2-ECBM). Several theoretical studies and worldwide demonstration sites have illustrated the potential of the process.Most of these projects experienced permeability reduction of the coalbed with time, leading to operational difficulties because of the loss of injectability. The permeability reduction is generally considered to be caused by the coal swelling that is induced by gas sorption, because it can narrow or close the cleat of the coalbed. As a result, the migration of injected CO2 in coal pore or cleat becomes more difficult. Therefore, sorption and swelling characterizations are important issues for forecasting the performance of aimed coalbed. In this work, CO2/CH4sorption and swelling isotherms of two Chinese block coals (QS and YQ) were measured simultaneously under different temperature and pressure conditions. It was found that the swelling ratio of coal block by CO2 sorption increased with the increase of the gas sorption amount until it approached to a value of ~3 mmol-gas/g-coal and decreased slightly afterwards for both coals; while the swelling ratio of coal block by CH4 sorption increased with the increase of the gas sorption amount in the entire test region for both coals. By correlating the gas sorption amount and the corresponding swelling ratio, it was found that the swelling ratio of coal block is independent of temperature and coal type when the gas sorption amount is less than ~2mmol/g-coal. The differential profile of the swelling ratio with respect to sorption amount is appeared with a maximum value at ~1 mmol/g-coal for CH4 and at ~1.8 mmol/g-coal for CO2. Based on the theories related to gas sorption and solid surface energy, a mathematical model which correlates sorption and swelling behavior

  12. Scrotal Swelling as a Complication of Hydrochlorothiazide Induced Acute Pancreatitis

    Directory of Open Access Journals (Sweden)

    Ivan Nikiforov

    2015-01-01

    Full Text Available Background. Scrotal swelling is a rare complication of acute pancreatitis with few reported cases in the literature. In this case report, we present a 59-year-old male with hydrochlorothiazide induced pancreatitis who developed scrotal swelling. Case Presentation. A 59-year-old male presented to the emergency department with sharp epigastric abdominal pain that radiated to the back and chest. On physical examination, he had abdominal tenderness and distention with hypoactive bowel sounds. Computed tomography (CT scan of the abdomen showed acute pancreatitis. The patient’s condition deteriorated and he was admitted to the intensive care unit (ICU. After he improved and was transferred out of the ICU, the patient developed swelling of the scrotum and penis. Ultrasound (US of the scrotum showed large hydrocele bilaterally with no varicoceles or testicular masses. Good blood flow was observed for both testicles. The swelling diminished over the next eight days with the addition of Lasix and the patient was discharged home in stable condition. Conclusion. Scrotal swelling is a rare complication of acute pancreatitis. It usually resolves spontaneously with conservative medical management such as diuretics and elevation of the legs.

  13. Modeling of cavity swelling-induced embrittlement in irradiated austenitic stainless steels

    International Nuclear Information System (INIS)

    Han, X.

    2012-01-01

    During long-time neutron irradiation occurred in Pressurized Water Reactors (PWRs), significant changes of the mechanical behavior of materials used in reactor core internals (made of 300 series austenitic stainless steels) are observed, including irradiation induced hardening and softening, loss of ductility and toughness. So far, much effect has been made to identify radiation effects on material microstructure evolution (dislocations, Frank loops, cavities, segregation, etc.). The irradiation-induced cavity swelling, considered as a potential factor limiting the reactor lifetime, could change the mechanical properties of materials (plasticity, toughness, etc.), even lead to a structure distortion because of the dimensional modifications between different components. The principal aim of the present PhD work is to study qualitatively the influence of cavity swelling on the mechanical behaviors of irradiated materials. A micromechanical constitutive model based on dislocation and irradiation defect (Frank loops) density evolution has been developed and implemented into ZeBuLoN and Cast3M finite element codes to adapt the large deformation framework. 3D FE analysis is performed to compute the mechanical properties of a polycrystalline aggregate. Furthermore, homogenization technique is applied to develop a Gurson-type model. Unit cell simulations are used to study the mechanical behavior of porous single crystals, by accounting for various effects of stress triaxiality, of void volume fraction and of crystallographic orientation, in order to study void effect on the irradiated material plasticity and roughness at polycrystalline scale. (author) [fr

  14. Swell-based in situ oxide removal methods for PDMS-copper particle composite corrosion sensing elements

    Science.gov (United States)

    Yang, Teng; Pan, Feng; Hutson, Jeremy; Srinivas, Keerthi; King, Jerry; Spearot, Douglas; Huang, Adam

    2012-04-01

    A micro-corrosion sensor technology utilizing PDMS (polydimethylsiloxane) and micro/nano -metal particles, as the sensing element, was proposed and currently under-development. One of the key challenges encountered is the removal of the native oxides inherently existing on the metal particles. Numerous techniques were experimented to counter this problem, with swell-based protocols being identified as the most promising solution. Swelling of the composite enhances the diffusion of oxide etchants into and etched oxides out of the material matrix. Two different swelling characterizations, utilizing liquid-based solvents and supercritical CO2 emersions, will be presented here. In terms of compatibility, common microfabrication solvents were used to evaluate the former, while supercritical CO2 is often used in the release of stiction sensitive microstructures. Both methods are classified as low temperature techniques (less than 100 degrees Celcius). Commonly, the composite exhibits a swelling ratio of 10-20%, exhibiting more sensitive to the percentage content of the metal particles albeit well below those reported in literature for pure cross -linked PDMS. The swelling time-constant is found to be on the order of minutes (CO2) to tens of minutes (liquid solvent) while oxide removal for cubed coupons with 6.35mm on each side is on the order of hours. Also in both cases, the oxide etching performance is dependent on the amount of dilation of the material and the mixing compatibility between the swelling agent and the etchant (such as acetic acid and hexafluoroacetylacetone, respectively for copper oxides). The etch

  15. Comparative analyses of water soaking and thickness swelling of particleboard versus different test methods

    Directory of Open Access Journals (Sweden)

    Điporović-Momčilović Milanka

    2008-01-01

    Full Text Available In regard to its hygroscopic properties, particleboard is dimensionally unstable material when exposed to water or in the atmosphere of high level of humidity. Since today several different standardized methods for determination of thickness swelling exist, the aim of this study was focused on comparison of different testing methods. In this aim, three different methods for determination of water soaking and thickness swelling were compared, two of which were defined by national standard SRPS D.C8.104 and one was defined by European standard EN 317. The results of testing of both properties have shown no significant difference between the EN method based on 50×50 mm test pieces and the SRPS method based on test pieces of 100×100 mm format, suggesting that these two methods can be used alternatively. On the other hand, the results obtained by the SRPS method utilizing the 25×25 mm test pieces, differed significantly from both previous methods. The results were lower for both water soaking and thickness swelling regardless of panel thickness.

  16. Computational modeling of tracheal angioedema due to swelling of the submucous tissue layer.

    Science.gov (United States)

    Gou, Kun; Pence, Thomas J

    2017-10-01

    Angioedema is a tissue-swelling pathology due to rapid change in soft tissue fluid content. Its occurrence in the trachea is predominantly localized to the soft mucous tissue that forms the innermost tracheal layer. The biomechanical consequences, such as airway constriction, are dependent upon the ensuing mechanical interactions between all of the various tissues that comprise the tracheal tube. We model the stress interactions by treating the trachea organ as a three-tissue system consisting of swellable mucous in conjunction with nonswelling cartilage and nonswelling trachealis musculature. Hyperelastic constitutive modeling is used by generalizing the standard anisotropic, incompressible soft tissue framework to incorporate the swelling effect. Finite element stress analysis then proceeds with swelling of the mucous layer providing the driving factor for the mechanical analysis. The amount of airway constriction is governed by the mechanical interaction between the three predominant tissue types. The detailed stress analysis indicates the presence of stress concentrations near the various tissue junctions. Because of the tissue's nonlinear mechanical behavior, this can lead to material stiffness fluctuations as a function of location on the trachea. Patient specific modeling is presented. The role of the modeling in the interpretation of diagnostic procedures and the assessment of therapies is discussed. Copyright © 2017 John Wiley & Sons, Ltd.

  17. Modeling of saturation and swelling effects in clays under different saline conditions

    International Nuclear Information System (INIS)

    Herbert, H.J.; Moog, H.C.

    2001-01-01

    For the safety assessment of underground repositories predictive models are needed which can describe the process of infiltration and swelling pressure in compacted bentonites used as buffer and sealing materials. The infiltration can be well described for laboratory scale experiments by the Second Fickian Law. However, there is no proof yet, that application of this law is permissable when its useage is extended to the large scale of a repository with much more complex boundary conditions. Different models exist for the prediction of the swelling pressure of bentonites in contact with water and saline solutions. All of them are applicable only to systems with homoionic bentonite in contact with pure water or NaCl solution. None of these models is applicable to mixed salt solutions at ionic strengths as they are encountered naturaly in repositories in salt formations. A pragmatic GRS approach for the solving of this problem is described in this paper. A three years GRS research programme on this subject has revealed that the main factors influencing the swelling pressure of the bentonite-brine system are the brine composition, the density of the compacted bentonite and the hydrostatic pressure. The boundary conditions which have to be observed are discussed and the principle of the new approach is described. (orig.)

  18. Low-temperature swelling in LWR internal components: a computational assessment

    Energy Technology Data Exchange (ETDEWEB)

    Stoller, Roger E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Golubov, Stanislav I. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Barashev, Alexander V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)

    2015-01-01

    A modern cluster dynamics model has been used to investigate the materials and irradiation parameters that control microstructural evolution under the relatively low-temperature exposure conditions that are representative of the operating environment for in-core light water reactor components. The focus is on components fabricated from austenitic stainless steel. The model accounts for the synergistic interaction between radiation-produced vacancies and the helium that is produced by nuclear transmutation reactions. Cavity nucleation rates are shown to be relatively high in this temperature regime (275 to 325 °C), but are sensitive to assumptions about the fine-scale microstructure produced under low-temperature irradiation. The cavity nucleation rates observed run counter to the expectation that void swelling would not occur under these conditions. This expectation was based on previous research on void swelling in austenitic steels in fast reactors. This misleading impression arose primarily from an absence of relevant data. The results of the computational modeling are generally consistent with recent data obtained by examining ex-service components. The long-term objective of this research is to provide a predictive model of void swelling at relevant lifetime exposures to support extended reactor operations.

  19. Microfabrication of Super Absorbent Polymer Structure Using Nanoimprinting and Swelling Process

    Science.gov (United States)

    Inaba, Tomomi; Kano, Tomonori; Miki, Norihisa

    2013-06-01

    Micro-fabrication technologies have been extensively studied to achieve smaller sizes and higher aspect ratios. When the features have sizes of a couple of micrometers or below, nano-imprinting can be an effective method for micro-fabrication at low cost. However, it is difficult to achieve aspect ratio greater than 1. In this research, we propose micro fabrication of super absorbent polymer (SAP) as a new material for micro devices. SAP swells by adding deionized water, which can be used as a post patterning process to enhance the aspect ratio of micro structures. Micropatterning of SAP must be conducted under thoroughly dry conditions and we used nano-imprinting processes. We successfully augmented an aspect ratio of the nano-imprinted micro holes of SAP from 0.65 to 1.2 by the swelling process. The proposed patterning and swelling process of SAP can be applicable to micro-fabricate high-aspect-ratio structures at low cost for high performance lab-on-a-chip.

  20. A constitutive equation of irradiation creep and swelling under neutron irradiation

    International Nuclear Information System (INIS)

    Murakami, Sumio; Mizuno, Mamoru; Okamoto, Toshiaki.

    1990-01-01

    A constitutive equation of irradiation creep for irradiated materials applicable to structural analyses in a multiaxial state of stress was developed. After reviewing microscopic mechanisms of irradiation creep and swelling, the relevant theories proposed from the view point of metallurgical physics and their applicability were discussed first. Then a constitutive model was developed by assuming that irradiation creep can be decomposed into irradiation-enhanced creep and irradiation-induced creep. By taking account of the SIPA (Stress Induced Preferential Absorption) mechanism, the irradiation-induced creep was represented by an isotropic tensor function of order one and zero with respect to stress, which is, at the same time, the function of neutron flux and neutron fluence. The volumetric part of the irradiation-induced creep was identified with swelling. The irradiation-enhanced creep was described by modifying Kachanov-Rabotnov creep damage theory by incorporating the effect of irradiation. Finally the irradiation creep and swelling of type 316 stainless steel at elevated temperatures were predicted by the proposed constitutive equation, and the numerical results were compared with the corresponding experimental results. (author)

  1. Spinal-cord swelling in acute multiple sclerosis

    International Nuclear Information System (INIS)

    Kikuchi, Seiji; Tashiro, Kunio; Naganuma, Mutsuo; Hida, Kazutoshi; Iwasaki, Yoshinobu; Abe, Hiroshi; Miyasaka, Kazuo

    1986-01-01

    Despite the frequent involvement of the spinal cord by multiple sclerosis, reports concerning neuroradiological findings regarding these lesions have been limited; most of them have demonstrated a normal or small spinal cord. Two cases of acute paraparesis showed evidence of spinal-cord swelling on myelography and CT myelography, initially suggesting the diagnosis of an intramedullary tumor. Spinal-cord swelling was demonstrated more clearly on CT myelography than on conventional myelography. The diagnosis of multiple sclerosis was made with the aid of the CSF findings, the clinical course, and the contracting-cord sign. The ''contracting-cord sign'' means the diminution of the spinal-cord diameter in the chronic stage. Since acute multiple sclerosis may produce spinal-cord swelling simulating a tumor, careful investigations are necessary to avoid unwarranted surgical interventions. (author)

  2. Adsorption and strain: The CO 2-induced swelling of coal

    Science.gov (United States)

    Vandamme, M.; Brochard, L.; Lecampion, B.; Coussy, O.

    2010-10-01

    Enhanced coal bed methane recovery (ECBM) consists in injecting carbon dioxide in coal bed methane reservoirs in order to facilitate the recovery of the methane. The injected carbon dioxide gets adsorbed at the surface of the coal pores, which causes the coal to swell. This swelling in confined conditions leads to a closure of the coal reservoir cleat system, which hinders further injection. In this work we provide a comprehensive framework to calculate the macroscopic strains induced by adsorption in a porous medium from the molecular level. Using a thermodynamic approach we extend the realm of poromechanics to surface energy and surface stress. We then focus on how the surface stress is modified by adsorption and on how to estimate adsorption behavior with molecular simulations. The developed framework is here applied to the specific case of the swelling of CO 2-injected coal, although it is relevant to any problem in which adsorption in a porous medium causes strains.

  3. Effect of temperature on swelling and bubble growth in metals

    International Nuclear Information System (INIS)

    Tiwari, G.P.

    1982-01-01

    The effect of temperature on the swelling of copper-boron alloys has been studied in the temperature range of 900-1040deg C. It is observed that beyond 1030deg C, swelling as well as the rate of bubble growth decrease. Similar characteristics of the bubble growth have been observed in aluminium-boron alloys also. At 590deg C, the bubble growth in aluminium-boron alloys is faster as compared to that at 640deg C. It thus appears that the swelling as well as the growth of the gas bubble are retarded at temperatures near the melting point in metals. Possible reasons for this kind of behaviour are discussed. (author)

  4. Equilibrium swelling of poly(methacrylic acid-g-ethylene glycol) hydrogels. Effect of swelling medium and synthesis conditions.

    Science.gov (United States)

    Mathur, A M; Hammonds, K F; Klier, J; Scranton, A B

    1998-07-31

    Responsive hydrogel networks comprising of poly(methacrylic acid) (PMAA) backbone and oligomeric ethylene glycol (PEG) grafts were synthesized by free-radical solution polymerization and their equilibrium swelling properties were characterized in aqueous solutions of a homologous series of alcohols. These hydrogels are known to exhibit swelling transitions in response to external stimuli which lead to formation or disruption of hydrogen-bonded complexes between the backbone and the grafts. Swelling studies performed in aqueous mixtures of methanol, ethanol and propanol revealed that the effectiveness of an alcohol in breaking the PMAA/PEG complexes increased as the aliphatic segment length of the alcohol was increased. These results confirm the importance of hydrophobic interactions for stabilizing the complexes. Studies performed to determine the effect of the synthesis conditions on the equilibrium swelling properties revealed that the equilibrium degree of swelling increased as the solvent fraction during synthesis was increased. Finally, molecular stimulations revealed that it is sterically possible to form complexes with a 1:1 stoichiometry between chains of poly(methacrylic acid) and poly(ethylene glycol) with essentially no additional bond strain.

  5. Calcium in the mechanism of ammonia-induced astrocyte swelling.

    Science.gov (United States)

    Jayakumar, Arumugam R; Rama Rao, Kakulavarapu V; Tong, Xiaoying Y; Norenberg, Michael D

    2009-05-01

    Brain edema, due largely to astrocyte swelling, is an important clinical problem in patients with acute liver failure. While mechanisms underlying astrocyte swelling in this condition are not fully understood, ammonia and associated oxidative/nitrosative stress appear to be involved. Mechanisms responsible for the increase in reactive oxygen/nitrogen species (RONS) and their role in ammonia-induced astrocyte swelling, however, are poorly understood. Recent studies have demonstrated a transient increase in intracellular Ca2+ in cultured astrocytes exposed to ammonia. As Ca2+ is a known inducer of RONS, we investigated potential mechanisms by which Ca2+ may be responsible for the production of RONS and cell swelling in cultured astrocytes after treatment with ammonia. Exposure of cultured astrocytes to ammonia (5 mM) increased the formation of free radicals, including nitric oxide, and such increase was significantly diminished by treatment with the Ca2+ chelator 1,2-bis-(o-aminophenoxy)-ethane-N,N,-N',N'-tetraacetic acid tetraacetoxy-methyl ester (BAPTA). We then examined the activity of Ca2+-dependent enzymes that are known to generate RONS and found that ammonia significantly increased the activities of NADPH oxidase (NOX), constitutive nitric oxide synthase (cNOS), and phospholipase A2 (PLA2) and such increases in activity were significantly diminished by BAPTA. Pre-treatment of cultures with 7-nitroindazole, apocyanin, and quinacrine, respective inhibitors of cNOS, NOX, and PLA2, all significantly diminished RONS production. Additionally, treatment of cultures with BAPTA or with inhibitors of cNOS, NOX, and PLA2 reduced ammonia-induced astrocyte swelling. These studies suggest that the ammonia-induced rise in intracellular Ca2+ activates free radical producing enzymes that ultimately contribute to the mechanism of astrocyte swelling.

  6. Reliability of Arch dams subject to concrete swelling

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, J.M.; Silva, H.S.; Pinho, S. de [Laboratorio Nacional de Engenharia Civil (LNEC), Lisboa (Portugal)] [and others

    1995-12-31

    In this report, results of several studies are presented. The main aim of those studies was to assess the reliability of the three arch dams, in which swelling occurred due to alkali- aggregate reactions in various stages of development and having different effects on their reliability: the Cahora-Bassa dam, in Mozambique, where swelling accumulated up to the moment are very moderate and their development is apparently homogeneous; Santa-Luzia dam, in Portugal, where accumulated swelling have already considerable magnitude, nevertheless, important fissuration has not been observed up to the moment due to the homogeneous development of the swelling process; Alto-Ceira dam, also in Portugal, where accumulated swelling have also considerable magnitude but with a heterogeneous development, causing in conjunction with thermal variations important fissuration. Mention is made of mineralogical, chemical and petrographic analyses carried out for identification of the nature of reactions developed in each case and the back-analysis and other technics used in the assessment of the magnitude and distribution of swelling. Results are presented of measurement tests of the ultrasonic pulse velocity, used both in the assessment of alterations in the physical properties of concretes and in the determination of the depth of fissuration. Results are also presented of tests for characterisation of the rheology of integral concrete. Lastly, considerations are made about the reliability of the works on the basis of studies and the results of analyses of the state of stress, performed by means of the finite element method, by assuming for either visco-elastic or visco-elastic-plastic behaviour.

  7. Temporomandibular joint osteochondromatosis: an unusual cause of preauricular swelling.

    LENUS (Irish Health Repository)

    Phelan, Eimear

    2012-02-01

    We report an unusual and rare cause of preauricular swelling and review the most recent literature concerning synovial osteochondromatosis of the temporomandibular joint. We report the clinical and radiologic findings of a case of synovial osteochondromatosis of the temporomandibular joint that presented as preauricular swelling in a female patient. This disease typically affects large joints; fewer than 100 cases reported in the literature affect the temporomandibular joint. This case illustrates that disorders of the temporomandibular joint should also be included in the differential diagnosis of patients who present with a preauricular mass.

  8. Encephalocele presenting as lower lid swelling: A rare case report

    Directory of Open Access Journals (Sweden)

    Vaibhav Kumar Jain

    2018-01-01

    Full Text Available Encephalocele is a rare congenital abnormality characterized by abnormal protrusion of brain and meninges through an opening in the skull. We report an 8-year-old girl who presented with a swelling in the right lower lid for the last 6 years. In her infancy, she had undergone surgery for a very small swelling located in the right nasolacrimal area. On further clinicoradiological evaluation, anterior encephalocele was diagnosed. This case highlights the uncommon site of anterior encephalocele; misdiagnosis and mismanagement of which could result in dreaded complications such as meningitis and cerebrospinal fluid leaking fistula formation.

  9. Influence of effective stress on swelling pressure of expansive soils

    Directory of Open Access Journals (Sweden)

    Baille Wiebke

    2016-01-01

    Full Text Available The volume change and shear strength behaviour of soils are controlled by the effective stress. Recent advances in unsaturated soil mechanics have shown that the effective stress as applicable to unsaturated soils is equal to the difference between the externally applied stress and the suction stress. The latter can be established based on the soil-water characteristic curve (SWCC of the soil. In the present study, the evolution of swelling pressure in compacted bentonite-sand mixtures was investigated. Comparisons were made between magnitudes of applied suction, suction stress, and swelling pressure.

  10. [Edematous swelling of the eyelids caused by contact allergy].

    Science.gov (United States)

    Blum, A; Brummer, C; Lischka, G

    1998-08-01

    Cosmetics and ophthalmological topical preparations are the main causes of allergic contact eczema about the eye. In most cases, clinical signs are conjunctival injection, blepharitis, periorbital dermatitis and edema of lids, often combined with itching. Pure edematous swelling of the eyelids should not immediately be blamed on a contact allergy, but sufficiently evaluated to exclude a benign or malignant process of the eyelids, orbita, lacrimal duct and paranasal sinus. We present a patient with pure edematous swelling of the eyelids due to a contact allergy by the sympathicomimetic phenylephrine hydrochloride, an uncommon allergen.

  11. QCM-D Investigation of Swelling Behavior of Layer-by-Layer Thin Films upon Exposure to Monovalent Ions.

    Science.gov (United States)

    O'Neal, Joshua T; Dai, Ethan Y; Zhang, Yanpu; Clark, Kyle B; Wilcox, Kathryn G; George, Ian M; Ramasamy, Nandha E; Enriquez, Daisy; Batys, Piotr; Sammalkorpi, Maria; Lutkenhaus, Jodie L

    2018-01-23

    Polyelectrolyte multilayers and layer-by-layer assemblies are susceptible to structural changes in response to ionic environment. By altering the salt type and ionic strength, structural changes can be induced by disruption of intrinsically bound ion pairs within the multilayer network via electrostatic screening. Notably, high salt concentrations have been used for the purposes of salt-annealing and self-healing of LbL assemblies with KBr, in particular, yielding a remarkably rapid response. However, to date, the structural and swelling effects of various monovalent ion species on the behavior of LbL assemblies remain unclear, including a quantitative view of ion content in the LbL assembly and thickness changes over a wide concentration window. Here, we investigate the effects of various concentrations of KBr (0 to 1.6 M) on the swelling and de-swelling of LbL assemblies formed from poly(diallyldimethylammonium) polycation (PDADMA) and poly(styrene sulfonate) polyanion (PSS) in 0.5 M NaCl using quartz-crystal microbalance with dissipation (QCM-D) monitoring as compared to KCl, NaBr, and NaCl. The ion content after salt exchange is quantified using neutron activation analysis (NAA). Our results demonstrate that Br - ions have a much greater effect on the structure of as-prepared thin films than Cl - at ionic strengths above assembly conditions, which is possibly caused by the more chaotropic nature of Br - . It is also found that the anion in general dominates the swelling response as compared to the cation because of the excess PDADMA in the multilayer. Four response regimes are identified that delineate swelling due to electrostatic repulsion, slight contraction, swelling due to doping, and film destruction as ionic strength increases. This understanding is critical if such materials are to be used in applications requiring submersion in chemically dynamic environments such as sensors, coatings on biomedical implants, and filtration membranes.

  12. The Swelling Behaviour of Polystyrene (PS)/ Polyvinylacetate (Pvac ...

    African Journals Online (AJOL)

    The Swelling Behaviour of Polystyrene (PS)/ Polyvinylacetate (Pvac) Blends in Different Solvents and the Effects of Ą-Cellulose used as Filler on the Electrical Conductivity. ... temperature range of 323-363K shows promising semi conducting ability which appreciated with amount of filler in the polymer-polymer matrix.

  13. Cell swelling and glycogen metabolism in hepatocytes from fasted rats

    NARCIS (Netherlands)

    Gustafson, L. A.; Jumelle-Laclau, M. N.; van Woerkom, G. M.; van Kuilenburg, A. B.; Meijer, A. J.

    1997-01-01

    Cell swelling is known to increase net glycogen production from glucose in hepatocytes from fasted rats by activating glycogen synthase. Since both active glycogen synthase and phosphorylase are present in hepatocytes, suppression of flux through phosphorylase may also contribute to the net increase

  14. Mechanism of activation of liver glycogen synthase by swelling

    NARCIS (Netherlands)

    Meijer, A. J.; Baquet, A.; Gustafson, L.; van Woerkom, G. M.; Hue, L.

    1992-01-01

    The mechanism linking the stimulation of liver glycogen synthesis to swelling induced either by amino acids or hypotonicity was studied in hepatocytes, in gel-filtered liver extracts, and in purified preparations of particulate glycogen to which glycogen-metabolizing enzymes are bound. High

  15. Evaluation Of Postoperative Facial Swelling Following The Surgical ...

    African Journals Online (AJOL)

    Context: The complications associated with the removal of impacted third molars should not be underestimated. The surgery entails incision, stripping of periosteum, bone and tooth removal, and suturing. Swelling is almost universal after this procedure which, affect patients daily life activities. Objectives: To assess the use ...

  16. Advanced liquefaction using coal swelling and catalyst dispersion techniques

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C.W. (Auburn Univ., AL (United States)); Gutterman, C. (Foster Wheeler Development Corp., Livingston, NJ (United States)); Chander, S. (Pennsylvania State Univ., University Park, PA (United States))

    1992-08-26

    Research in this project centers upon developing a new approach to the direct liquefaction of coal to produce an all-distillate product slate at a sizable cost reduction over current technology. The approach integrates all aspects of the coal liquefaction process including coal selection, pretreatment, coal swelling with catalyst impregnation, coal liquefaction experimentation, product recovery with characterization, alternate bottoms processing, and a technical assessment including an economic evaluation. The project is being carried out under contract to the United States Department of Energy. On May 28, 1992, the Department of Energy authorized starting the experimental aspects of this projects; therefore, experimentation at Amoco started late in this quarterly report period. Research contracts with Auburn University, Pennsylvania State University, and Foster Wheeler Development Corporation were signed during June, 1992, so their work was just getting underway. Their work will be summarized in future quarterly reports. A set of coal samples were sent to Hazen Research for beneficiation. The samples were received and have been analyzed. The literature search covering coal swelling has been up-dated, and preliminary coal swelling experiments were carried out. Further swelling experimentation is underway. An up-date of the literature on the liquefaction of coal using dispersed catalysts is nearing completion; it will be included in the next quarterly report.

  17. Splenogonadal fusion: a forgotten cause of testicular swelling in ...

    African Journals Online (AJOL)

    of suspicion of a testicular tumor [4]. This is of great importance and to obviate this, physicians caring for these patients should be aware of this differential diagnosis and if there is doubt intraoperatively regarding the nature of the swelling, frozen section biopsy should be performed to avoid unnecessary orchiectomy.

  18. Grewia Gum 1: Some Mechanical and Swelling Properties of ...

    African Journals Online (AJOL)

    Purpose: To study the mechanical and dynamic swelling properties of grewia gum, evaluate its compression behaviour and determine the effect of drying methods on its properties. Methods: Compacts (500 mg) of both freeze-dried and air-dried grewia gum were separately prepared by compression on a potassium bromide ...

  19. Kimura's disease: A case presentation of postauricular swelling ...

    African Journals Online (AJOL)

    Kimura's disease: A case presentation of postauricular swelling. A Rajesh, T Prasanth, V.C. Naga Sirisha, M.D.S. Azmi. Abstract. Kimura's disease (KD) is a rare chronic inflammatory disease of subcutaneous tissues and occurs predominantly in head and neck region. It is seen primarily in young Asian males. Typical clinical ...

  20. Clozapine- induced recurrent and transient parotid gland swelling

    African Journals Online (AJOL)

    mainly due to its side effect of agranulocytosis. Hypersalivation is another distressing and common side effect of clozapine which occurs in about 23 % of patients.3. Hypersalivation , a poorly understood paradoxical side effect of clozapine, may sometimes cause salivary gland swelling. Rarely, the anticholinergic effect of ...

  1. Laboratory tests of hydraulic fracturing and swell healing

    DEFF Research Database (Denmark)

    Thunbo, Christensen Claes; Foged, Christensen Helle; Foged, Niels

    1998-01-01

    New laboratory test set-ups and test procedures are described - for testing the formation of hydraulically induced fractures as well as the potential for subsequent fracture closurefrom the relase of a swelling potential. The main purpose with the tests is to provide information on fracturing...

  2. Multiple renal anomalies associated with encapsulated swellings of ...

    African Journals Online (AJOL)

    The current observation reports the occurrence of the left renal anomalies and encapsulated swellings involving the left sciatic nerve in a 47 years old male cadaver. Renal anomalies consisted of left double kidney, left bifid ureter and double arterial supply to the left kidney. The double kidney consisted of the two upper and ...

  3. Modeling SiC swelling under irradiation: Influence of amorphization

    CERN Document Server

    Romano, A; Defranceschi, M; Yip, S

    2003-01-01

    Irradiation-induced swelling of SiC is investigated using a molecular dynamics simulation-based methodology. To mimic the effect of heavy ion irradiation extended amorphous areas of various sizes are introduced in a crystalline SiC sample, and the resulting configurations are relaxed using molecular dynamics at constant pressure. Simulation results compare very well with data from existing ion implantation experiments. Analysis of the relaxed configurations shows very clearly that SiC swelling does not scale linearly with the amorphous fraction introduced. Two swelling regimes are observed depending on the size of the initial amorphous area: for small amorphous zones swelling scales like the amorphous fraction to the power 2/3, while for larger areas it scales like the amorphous fraction to the powers 2/3 and 4/3. Similar dependences on the amorphous fraction are obtained for the number of homonuclear bonds present in the initial amorphous volume and for the number of short bonds created at the interface betw...

  4. Splenogonadal fusion: A forgotten cause of testicular swelling in ...

    African Journals Online (AJOL)

    Splenogonadal fusion is a rare congenital anomaly in which there is fusion of the spleen and the gonad. This report describes a 25-month-old male child who presented with left scrotal swelling. On exploration, a discontinuous type of splenogonadal fusion was found. It was successfully and completely separated from the ...

  5. Swelling behavior of 20% CW 316 Stainless Steel cladding irradiated with and without adjacent fuel

    International Nuclear Information System (INIS)

    Makenas, B.J.; Bates, J.F.; Jost, J.W.

    1982-06-01

    Swelling behavior has been evaluated for irradiated 20% CW 316 Stainless Steel used as cladding material for mixed-oxide fuel pins in EBR-II. This behavior has been compared statistically with the behavior of a large number of specimens which were irradiated without adjacent fuel in the same reactor. In spite of the chemical environment and stresses experienced by fueled cladding, the fueled and nonfueled cladding appear to behave in a similar manner although some divergence was noted for one of the cases studied

  6. Irradiated PVAl membrane swelled with chitosan solution as dermal equivalent

    International Nuclear Information System (INIS)

    Rodas, A.C.D.; Ohnuki, T.; Mathor, M.B.; Lugao, A.B.

    2005-01-01

    Synthetic membranes as dermal equivalent can be applied at in vitro studies for developing new transdermal drugs or cosmetics. These membranes could be composed to mimic the dermis and seed cultivated keratinocytes as epidermal layer on it. The endothelial cells ingrowth to promote neovascularization and fibroblasts ingrowth to promote the substitution of this scaffold by natural components of the dermis. As, they can mimic the scaffold function of dermis; the membranes with biological interaction could be used for in vivo studies as dermal equivalent. For this application, poly(vinyl alcohol) (PVAl) membranes crosslinked by gamma radiation were swelled with chitosan solution. PVAl do not interact with the organism when implanted and is intended to mimic the mechanical characteristics of the dermal scaffold. The chitosan as a biocompatible biosynthetic polysaccharide were incorporated into PVAl membranes to improve the organism response. Degradation of chitosan by the organism occurs preferably by hydrolysis or enzymatic action, for example, by lysozyme. For this purpose the swelling kinetic of PVAl membranes with chitosan solution were performed and it was verified their degradation in vitro. The results showed that the swelling equilibrium of the PVAl membranes with chitosan membranes was reached in 120 h with average swelling of 1730%. After swelling, PVAl and chitosan/PVAl membranes were dried and immersed in phosphate buffer solution pH 5.7 and pH 7.4, with and without lysozyme, as those pH values are the specific physiologic pH for external skin and the general physiological pH for the organism, respectively. It was verified that the pure PVAl membrane did not showed change in their mass during 14 days. PVAl membranes swelled with chitosan solution showed mass decrease from 1 to 14 days inside these solutions. The highest mass decrease was verified at pH 5.7 in phosphate buffer solution without lysozyme. The smallest mass decrease was verified at pH 7.4 in

  7. Materialism.

    Science.gov (United States)

    Melnyk, Andrew

    2012-05-01

    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website. Copyright © 2012 John Wiley & Sons, Ltd.

  8. Evaluating the swelling, erosion, and compaction properties of cellulose ethers.

    Science.gov (United States)

    Ghori, Muhammad U; Grover, Liam M; Asare-Addo, Kofi; Smith, Alan M; Conway, Barbara R

    2018-02-01

    Swelling, erosion, deformation, and consolidation properties can affect the performance of cellulose ethers, the most commonly used matrix former in hydrophilic sustained tablet formulations. The present study was designed to comparatively evaluate the swelling, erosion, compression, compaction, and relaxation properties of the cellulose ethers in a comprehensive study using standardised conditions. The interrelationship between various compressional models and the inherent deformation and consolidation properties of the polymers on the derived swelling and erosion parameters are consolidated. The impact of swelling (K w ) on erosion rates (K E ) and the inter-relationship between Heckel and Kawakita plasticity constants was also investigated. It is evident from the findings that the increases in both substitution and polymer chain length led to higher K w , but a lower K E ; this was also true for all particle size fractions regardless of polymer grade. Smaller particle size and high substitution levels tend to increase the relative density of the matrix but reduce porosity, yield pressure (P y ), Kawakita plasticity parameter (b -1 ) and elastic relaxation. Both K W versus K E (R 2  = 0.949-0.980) and P y versus. b -1 correlations (R 2  = 0.820-0.934) were reasonably linear with regards to increasing hydroxypropyl substitution and molecular size. Hence, it can be concluded that the combined knowledge of swelling and erosion kinetics in tandem with the in- and out-of-die compression findings can be used to select a specific polymer grade and further to develop and optimize formulations for oral controlled drug delivery applications.

  9. Swelling, ion uptake and biodegradation studies of PE film modified through radiation induced graft copolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Inderjeet, E-mail: ij_kaur@hotmail.com [Department Chemistry, HPU Shimla 171005 (India); Gupta, Nitika; Kumari, Vandna [Department Chemistry, HPU Shimla 171005 (India)

    2011-09-15

    An attempt to develop biodegradable polyethylene film grafting of mixture of hydrophilic monomers methacrylic acid (MAAc) and acrylamide (AAm) onto PE film has been carried out by preirradiation method using benzoyl peroxide as the radical initiator. Since ether linkages are susceptible to easy cleavage during degradation process, PE film was irradiated before the grafting reactions by {gamma}-rays to introduce peroxidic linkages (PE-OO-PE) that offer sites for grafting. The effect of irradiation dose, monomer concentration, initiator concentration, temperature, time and amount of water on the grafting percent was determined. Maximum percentage of grafting of binary mixture (MAAc+AAm), (1792%) was obtained at a total concentration of binary monomer mixture=204.6x10{sup -2} mol/L ([MAAc]=176.5x10{sup -2} mol/L, [AAm]=28.1x10{sup -2} mol/L), [BPO]=8.3x10{sup -2} mol/L at 100 deg. C in 70 min. The grafted PE film was characterized by the Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopic (SEM) methods. Some selective properties of grafted films such as swelling studies, ion uptake and biodegradation studies have been investigated. The grafted films show good swelling in water, ion uptake studies shows promising results for desalination of brackish water and the soil burial test shows that PE film grafted with binary monomer mixture degrades up to 47% within 50 days. - Highlights: > Binary mixture of methacrylic acid (MAAc) and acrylamide (AAm) onto PE film by preirradiation method was carried out. > Graft copolymers of MAAc+AAm and PE film were characterized by FTIR, TGA and SEM studies and was found to be thermally stable. > Grafting of MAAc+AAm improved swelling behavior giving maximum swelling (485.71%) in water as against PE with 0% swelling. > The grafted PE-g-poly (MAAc-co-AAm) behaves as an excellent material for ion separation. > Biodegradation studies by soil burial test showed 47.19% of

  10. Exposure of natural rubber to personal lubricants--swelling and stress relaxation as potential indicators of reduced seal integrity of non-lubricated male condoms.

    Science.gov (United States)

    Sarkar Das, Srilekha; Coburn, James C; Tack, Charles; Schwerin, Matthew R; Richardson, D Coleman

    2014-07-01

    Male condoms act as mechanical barriers to prevent passage of body fluids. For effective use of condoms the mechanical seal is also expected to remain intact under reasonable use conditions, including with personal lubricants. Absorption of low molecular weight lubricant components into the material of male condoms may initiate material changes leading to swelling and stress relaxation of the polymer network chains that could affect performance of the sealing function of the device. Swelling indicates both a rubber-solvent interaction and stress relaxation, the latter of which may indicate and/or result in a reduced seal pressure in the current context. Swelling and stress relaxation of natural rubber latex condoms were assessed in a laboratory model in the presence of silicone-, glycol-, and water-based lubricants. Within 15 minutes, significant swelling (≥6 %) and stress reduction (≥12 %) of condoms were observed with 2 out of 4 silicone-based lubricants tested, but neither was observed with glycol- or water-based lubricants tested. Under a given strain, reduction in stress was prominent during the swelling processes, but not after the process was complete. Lubricant induced swelling and stress relaxation may loosen the circumferential stress responsible for the mechanical seal. Swelling and stress relaxation behavior of latex condoms in the presence of personal lubricants may be useful tests to identify lubricant-rooted changes in condom-materials. For non-lubricated latex condoms, material characteristics--which are relevant to failure--may change in the presence of a few silicone-based personal lubricants. These changes may in turn induce a loss of condom seal during use, specifically at low strain conditions. Published by Elsevier Inc.

  11. Bentonite swelling pressure in strong NaCl solutions. Correlation of model calculations to experimentally determined data

    Energy Technology Data Exchange (ETDEWEB)

    Karnland, O. [Clay Technology, Lund (Sweden)

    1998-01-01

    A number of quite different quantitative models concerning swelling pressure in bentonite clay have been proposed. This report discusses a number of models which possibly can be used also for saline conditions. A discrepancy between calculated and measured values was noticed for all models at brine conditions. In general the models predicted a too low swelling pressure compared to what was experimentally found. An osmotic component in the clay/water system is proposed in order to improve the previous conservative use of the thermodynamic model. Calculations of this osmotic component is proposed to be made by use of the clay cation exchange capacity and Donnan equilibrium. Calculations made by this approach showed considerably better correlation to literature laboratory data, compared to calculations made by the previous conservative use of the thermodynamic model. A few verifying laboratory tests were made and are briefly described in the report. The improved model predicts a substantial bentonite swelling pressure also in a saturated sodium chloride solution if the density of the system is sufficiently high. This means in practice that the buffer in a KBS-3 repository will give rise to an acceptable swelling pressure, but that the positive effects of mixing bentonite into a backfill material will be lost if the system is exposed to brines. (orig.). 14 refs.

  12. Bentonite swelling pressure in strong NaCl solutions. Correlation between model calculations and experimentally determined data

    Energy Technology Data Exchange (ETDEWEB)

    Karnland, O. [Clay Technology, Lund (Sweden)

    1997-12-01

    A number of quite different quantitative models concerning swelling pressure in bentonite clay have been proposed by different researchers over the years. The present report examines some of the models which possibly may be used also for saline conditions. A discrepancy between calculated and measured values was noticed for all models at brine conditions. In general the models predicted a too low swelling pressure compared to what was experimentally found. An osmotic component in the clay/water system is proposed in order to improve the previous conservative use of the thermodynamic model. Calculations of this osmotic component is proposed to be made by use of the clay cation exchange capacity and Donnan equilibrium. Calculations made by this approach showed considerably better correlation to literature laboratory data, compared to calculations made by the previous conservative use of the thermodynamic model. A few verifying laboratory tests were made and are briefly described in the report. The improved thermodynamic model predicts substantial bentonite swelling pressures also in saturated sodium chloride solution if the density of the system is high enough. In practice, the model predicts a substantial swelling pressure for the buffer in a KBS-3 repository if the system is exposed to brines, but the positive effects of mixing bentonite into a backfill material will be lost, since the available compaction technique does not give a sufficiently high bentonite density 37 refs, 15 figs

  13. Nucleation and swelling in electron irradiated austenitic stainless steels in temperature range 400∼720 degree C

    International Nuclear Information System (INIS)

    Qian Jiapu; Lu Liping; Chen Jiming; Sun Jiguang; Zhao Zhuoyong

    1994-10-01

    A study of the influence of temperature on swelling behavior in electron irradiated austenitic stainless steels has been performed with a high voltage electron microscope (HVEM) in the temperature range 400 to 720 degree C. The specimen materials were solution annealed (SA) 316 stainless steel (SS), cold worked (CW) 316 SS and Ti-modified austenitic stainless steel (Ti-mod. SS). The electron energy in HVEM was 1 MeV. The results of mean void density, mean void diameter, void swelling, swelling rate and incubation dose vs. dose and temperature are presented. It is suggested that the irradiation temperature influenced the microstructure, overall sink strength and relative strength of neutral sinks to that of biased sinks in the specimens and so made the void nucleation, void growth and swelling behavior differently in 316 SA, 316 CW and Ti-mod. SS. The influence of He pre-implantation on void nucleation in electron irradiated austenitic stainless steels has also been studied. The experiments indicated that the helium was active void nucleus but had no direct impact on void growth

  14. Bentonite swelling pressure in strong NaCl solutions. Correlation between model calculations and experimentally determined data

    International Nuclear Information System (INIS)

    Karnland, O.

    1997-12-01

    A number of quite different quantitative models concerning swelling pressure in bentonite clay have been proposed by different researchers over the years. The present report examines some of the models which possibly may be used also for saline conditions. A discrepancy between calculated and measured values was noticed for all models at brine conditions. In general the models predicted a too low swelling pressure compared to what was experimentally found. An osmotic component in the clay/water system is proposed in order to improve the previous conservative use of the thermodynamic model. Calculations of this osmotic component is proposed to be made by use of the clay cation exchange capacity and Donnan equilibrium. Calculations made by this approach showed considerably better correlation to literature laboratory data, compared to calculations made by the previous conservative use of the thermodynamic model. A few verifying laboratory tests were made and are briefly described in the report. The improved thermodynamic model predicts substantial bentonite swelling pressures also in saturated sodium chloride solution if the density of the system is high enough. In practice, the model predicts a substantial swelling pressure for the buffer in a KBS-3 repository if the system is exposed to brines, but the positive effects of mixing bentonite into a backfill material will be lost, since the available compaction technique does not give a sufficiently high bentonite density

  15. Bentonite swelling pressure in strong NaCl solutions. Correlation of model calculations to experimentally determined data

    International Nuclear Information System (INIS)

    Karnland, O.

    1998-01-01

    A number of quite different quantitative models concerning swelling pressure in bentonite clay have been proposed. This report discusses a number of models which possibly can be used also for saline conditions. A discrepancy between calculated and measured values was noticed for all models at brine conditions. In general the models predicted a too low swelling pressure compared to what was experimentally found. An osmotic component in the clay/water system is proposed in order to improve the previous conservative use of the thermodynamic model. Calculations of this osmotic component is proposed to be made by use of the clay cation exchange capacity and Donnan equilibrium. Calculations made by this approach showed considerably better correlation to literature laboratory data, compared to calculations made by the previous conservative use of the thermodynamic model. A few verifying laboratory tests were made and are briefly described in the report. The improved model predicts a substantial bentonite swelling pressure also in a saturated sodium chloride solution if the density of the system is sufficiently high. This means in practice that the buffer in a KBS-3 repository will give rise to an acceptable swelling pressure, but that the positive effects of mixing bentonite into a backfill material will be lost if the system is exposed to brines. (orig.)

  16. The effect of cigarette smoking on the severity of pain, swelling and trismus after the surgical extraction of impacted mandibular third molar

    Science.gov (United States)

    2013-01-01

    Objective: The study objective was to investigate the effect of cigarette smoking on the severity of pain, swelling and trismus on male after the surgical removal of impacted lower third molar. Material and Methods: This prospective comparative study was conducted for 150 male in two groups of patients, smokers and non-smokers. Each group consisted of 75 patients; smoking patient were the ones who smoke more than twenty cigarettes per day for more than one year of continuous smoking. Postoperative pain was evaluated using a visual analog scale (VAS) and the degree of swelling was evaluated through facial reference points’ variation. The presence of trismus was analyzed through measurement of the interincisal distance (IID). Result: Clinical and radiographic examinations were carried out. Data regarding the age, gender, angulations type, depth and width of impactions were evaluated and analyzed The severity of pain, swelling and trismus on the 1st, 2nd , 5th and 7thday postoperatively was estimated. In both groups the pain and trismus were reported to be in peak level during the first post-operative day while post-operative swelling reaches its peak level in the second postoperative day. Conclusion: Cigarettes smoking do not have any significant relationship with the severity of pain, swelling and trismus after surgical removal of lower third molar on male gender. Key words:Cigarettes smoking, pain, swelling, trismus, impacted lower third molars. PMID:24455065

  17. Mechanical interaction buffer/backfill. Finite element calculations of the upward swelling of the buffer against both dry and saturated backfill

    International Nuclear Information System (INIS)

    Boergesson, Lennart; Hernelind, Jan

    2009-10-01

    The mechanical interaction between the buffer material in the deposition hole and the backfill material in the deposition tunnel is an important process in the safety assessment since the primary function of the backfill is to keep the buffer in place and not allow it to expand too much and thereby loose too much of its density and barrier properties. In order to study the upwards swelling of the buffer and the subsequent density reduction a number of finite element calculations have been performed. The calculations have been done with the FE-program Abaqus with 3D-models of a deposition hole and the deposition tunnel. In order to refine the modelling only the two extreme cases of completely un-wetted (dry) and completely water saturated (wet) backfill have been modelled. For the wet case the influence of different factors has been studied while only one calculation of the dry case has been done. The calculated upwards swelling of the buffer varied between 2 and 15 cm for the different wet cases while it was about 10 cm for the dry case. In the wet reference case the E-modulus of the block and pellets fillings was 50 MPa and 3.24 MPa respectively, the friction angle between the buffer and the rock and canister was 8.7 deg and there were no swelling pressure from the backfill. There is a strong influence of the friction angle on both the upwards swelling and the canister heave. The friction is important for preventing especially canister displacements. The unrealistic case of no friction yielded strong unacceptable influence on the buffer with an upwards swelling of 15 cm and a strong heave of 5 cm of the canister. The influence of the backfill stiffness is as expected strong. Both buffer swelling and canister heave are twice as large at the E-modulus E = 25 MPa than at the E-modulus E = 100 MPa. The influence of the stiffness of the pellets filling is not strong since there are no pellets on the floor in the model used. The influence of the swelling pressure of the

  18. Mechanical interaction buffer/backfill. Finite element calculations of the upward swelling of the buffer against both dry and saturated backfill

    Energy Technology Data Exchange (ETDEWEB)

    Boergesson, Lennart (Clay Technology AB, Lund (Sweden)); Hernelind, Jan (5T-Engineering AB, Vaesteraas (Sweden))

    2009-10-15

    The mechanical interaction between the buffer material in the deposition hole and the backfill material in the deposition tunnel is an important process in the safety assessment since the primary function of the backfill is to keep the buffer in place and not allow it to expand too much and thereby loose too much of its density and barrier properties. In order to study the upwards swelling of the buffer and the subsequent density reduction a number of finite element calculations have been performed. The calculations have been done with the FE-program Abaqus with 3D-models of a deposition hole and the deposition tunnel. In order to refine the modelling only the two extreme cases of completely un-wetted (dry) and completely water saturated (wet) backfill have been modelled. For the wet case the influence of different factors has been studied while only one calculation of the dry case has been done. The calculated upwards swelling of the buffer varied between 2 and 15 cm for the different wet cases while it was about 10 cm for the dry case. In the wet reference case the E-modulus of the block and pellets fillings was 50 MPa and 3.24 MPa respectively, the friction angle between the buffer and the rock and canister was 8.7 deg and there were no swelling pressure from the backfill. There is a strong influence of the friction angle on both the upwards swelling and the canister heave. The friction is important for preventing especially canister displacements. The unrealistic case of no friction yielded strong unacceptable influence on the buffer with an upwards swelling of 15 cm and a strong heave of 5 cm of the canister. The influence of the backfill stiffness is as expected strong. Both buffer swelling and canister heave are twice as large at the E-modulus E = 25 MPa than at the E-modulus E = 100 MPa. The influence of the stiffness of the pellets filling is not strong since there are no pellets on the floor in the model used. The influence of the swelling pressure of the

  19. Reirradiation in FFTF of swelling-resistant Path A alloys previously irradiated in HFIR

    International Nuclear Information System (INIS)

    Maziasz, P.J.

    1985-01-01

    Disks of Path A Prime Candidate Alloys (in several pretreatment conditions) and several heats of cold-worked (CW) type 316 and D9 type austenitic stainless steels have been irradiated in HFIR at 300, 500, and 600 0 C to fluences producing about 10 to 44 dpa and 450 to 3600 at. ppm He. These samples are being reirradiated in the Materials Open Test Assembly (MOTA) in FFTF at 500 and 600 0 C, together (side by side) with previously unirradiated disks of exactly the same materials, to greater than 100 dpa. These samples many of which have either very fine helium cluster or helium bubble distributions after HFIR irradiation, are intended to test the possibility and magnitude of a helium-induced extension of the initial low-swelling transient regime relative to the void swelling behavior normally found during FFTF irradiation. Further, these samples will reveal the microstructural stability or evolution differences that correlate with such helium effects. 17 references, 4 tables

  20. Swelling and mechanical properties of physically crosslinked poly(vinyl alcohol) hydrogels.

    Science.gov (United States)

    Suzuki, Atsushi; Sasaki, Saori

    2015-12-01

    Physically crosslinked poly(vinyl alcohol) gels are versatile biomaterials due to their excellent biocompatibility. In the past decades, physically crosslinked poly(vinyl alcohol) and poly(vinyl alcohol)-based hydrogels have been extensively studied for biomedical applications. However, these materials have not yet been implemented due to their mechanical strength. Physically crosslinked poly(vinyl alcohol) gels consist of a swollen amorphous network of poly(vinyl alcohol) physically crosslinked by microcrystallites. Although the mechanical properties can be improved to some extent by controlling the distribution of microcrystallites on the nano- and micro-scales, enhancing the mechanical properties while maintaining high water content remains very difficult. It may be technologically impossible to significantly improve the mechanical properties while keeping the gel's high water absorbance ability using conventional fabrication methods. Physical and chemical understandings of the swelling and mechanical properties of physically crosslinked poly(vinyl alcohol) gels are considered here; some promising strategies for their practical applications are presented. This review focuses more on the recent studies on swelling and mechanical properties of poly(vinyl alcohol) hydrogels, prepared using only poly(vinyl alcohol) and pure water with no other chemicals, as potential biomedical materials. © IMechE 2015.

  1. A FACSIMILE code for calculating void swelling and creep, with vacancy loops present: version VS4

    International Nuclear Information System (INIS)

    Windsor, M.E.; Bullough, R.; Wood, M.H.

    1981-10-01

    This FACSIMILE code calculates void swelling and creep of irradiated materials, taking into account the effects of cavities, interstitial loops, vacancy loops, dislocation network and either grain boundaries or foil surfaces. The creep calculations are based on SIPA theory (stress induced preferred absorption), with no preferred nucleation. Either interactive or non-interactive options are available for the sink strength equations, but rate limitation is not incorporated. FACSIMILE is a computer program for solving simultaneous differential equations, and this VS4 code is one of a series of codes for calculating void swelling using increasingly complex theories. Other reports describing the VS1 and VS2 codes explain their use under control of the TSO system of the Harwell IBM 3033 computer, and explain the basic organization of the codes as required for use by FACSIMILE. The creep theory assumes that the material is under a constant uniaxial tensile stress during the irradiation. Three directions are considered for network parameters relative to the direction of the stress, and two directions for interstitial and vacancy loops. To give a full picture of these various contributions to the total creep, a large set of output parameter values are printed for each demanded dose value via a FORTRAN subroutine. (author)

  2. Structure and radiation induced swelling of steels and alloys

    International Nuclear Information System (INIS)

    Parshin, A.M.

    1983-01-01

    Regularities of vacancy void formation and radiation induced swelling of austenitic chromium-nickel steels and alloyse ferritic steels as well as titanium α-alloys under radiation by light and heavy ions and neutrons are considered. Possible methods for preparation of alloys with increased resistance to radiation swelling are described. Accounting for investigations into ferritic steels and α-alloys of titanium the basic way of weakening vacancy smelling is development of continuous homogeneous decomposition of solid solution using alloying with vividly expressed incubation period at a certain volumetric dilatation as well as decompositions of the type of ordering, K-state, lamination of solid solutions, etc. Additional alloying of solid solutions is also shown to be necessary for increasing recrystallization temperature of cold-deformed steel

  3. Swell activated chloride channel function in human neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, Michael D. [Leukocyte and Ion Channel Research Laboratory, School of Health and Biosciences, University of East London, Stratford Campus, London E15 4LZ (United Kingdom); Ahluwalia, Jatinder, E-mail: j.ahluwalia@uel.ac.uk [Leukocyte and Ion Channel Research Laboratory, School of Health and Biosciences, University of East London, Stratford Campus, London E15 4LZ (United Kingdom)

    2009-04-17

    Non-excitable cells such as neutrophil granulocytes are the archetypal inflammatory immune cell involved in critical functions of the innate immune system. The electron current generated (I{sub e}) by the neutrophil NADPH oxidase is electrogenic and rapidly depolarises the membrane potential. For continuous function of the NADPH oxidase, I{sub e} has to be balanced to preserve electroneutrality, if not; sufficient depolarisation would prevent electrons from leaving the cell and neutrophil function would be abrogated. Subsequently, the depolarisation generated by the neutrophil NADPH oxidase I{sub e} must be counteracted by ion transport. The finding that depolarisation required counter-ions to compensate electron transport was followed by the observation that chloride channels activated by swell can counteract the NADPH oxidase membrane depolarisation. In this mini review, we discuss the research findings that revealed the essential role of swell activated chloride channels in human neutrophil function.

  4. SuperLig Ion Exchange Resin Swelling and Buoyancy Study

    International Nuclear Information System (INIS)

    Hassan, N.M.

    2000-01-01

    The objective of this study was to achieve a fundamental understanding of SuperLig resin swelling and shrinking characteristics, which lead to channeling and early breakthrough during loading cycles. The density of salt solution that causes resin floating was also determined to establish a limit for operation. Specific tests performed include (a) pH dependence, (b) ionic strength dependence and (c) buoyancy effect vs. simulant composition

  5. Clayey landslide initiation and acceleration strongly modulated by soil swelling

    Science.gov (United States)

    Schulz, William; Smith, Joel B.; Wang, Gonghui; Jiang, Yao; Roering, Joshua J.

    2018-01-01

    Largely unknown mechanisms restrain motion of clay-rich, slow-moving landslides that are widespread worldwide and rarely accelerate catastrophically. We studied a clayey, slow-moving landslide typical of thousands in northern California, USA, to decipher hydrologic-mechanical interactions that modulate landslide dynamics. Similar to some other studies, observed pore-water pressures correlated poorly with landslide reactivation and speed. In situ and laboratory measurements strongly suggested that variable pressure along the landslide's lateral shear boundaries resulting from seasonal soil expansion and contraction modulated its reactivation and speed. Slope-stability modeling suggested that the landslide's observed behavior could be predicted by including transient swell pressure as a resistance term, whereas modeling considering only transient hydrologic conditions predicted movement 5–6 months prior to when it was observed. All clayey soils swell to some degree; hence, our findings suggest that swell pressure likely modulates motion of many landslides and should be considered to improve forecasts of clayey landslide initiation and mobility.

  6. Bias factors for radiation creep, growth and swelling

    International Nuclear Information System (INIS)

    Nichols, F.A.

    1980-01-01

    Central to the present concepts of the origin of the radiation-induced creep, growth and swelling phenomena is the relative interaction of interstitials and vacancies with various sinks. Radiation-induced climb of dislocations, which figures in many theories of radiation creep and growth, requires the absorption of an excess of either vacancies or interstitials. On the other hand, radiation swelling requires the absorption of an excess of vacancies to effect void growth. These relative preferences are normally expressed in theoretical models by certain bias factors, or capture efficiencies, usually assumed to be constant. Several attempts have been made to estimate their magnitude theoretically but all are seen to involve errors or physically unrealistic assumptions. We present here a unified treatment in which these various bias factors are estimated in a self-consistent model which incorporates, for the first time, all the essential physics, i.e., defect production, interactions of both vacancies and interstitials with sinks and the presence of two types of sinks. We present quantitative evaluations for the SIPA creep model and for radiation swelling, and compare with previous estimates of these phenomena. (orig.)

  7. Bias factors for radiation creep, growth and swelling

    International Nuclear Information System (INIS)

    Nichols, F.A.

    1979-01-01

    Central to the present concepts of the origin of the radiation-induced creep, growth and swelling phenomena is the relative interaction of interstitials and vacancies with various sinks. Radiation-induced climb of dislocations, which figures in many theories of radiation creep and growth, requires the absorption of an excess of either vacancies or interstitials. On the other hand, radiation swelling requires the absorption of an excess of vacancies to affect void growth. These relative preferences are normally expressed in theoretical models by certain bias factors, or capture efficiencies, usually assumed to be constant. Several attempts have been made to estimate their magnitude theoretically but all are seen to involve errors or physically unrealistic assumptions. We present here a unified treatment in which these various bias factors are estimated in a self-consistent model which incorporates, for the first time, all the essential physics, i.e., defect production, interactions of both vacancies and interstitials with sinks and the presence of two types of sinks. We present quantitative evaluations for the SIPA creep model and for radiation swelling, and compare with previous estimates of these phenomena

  8. Linking natural microstructures with numerical modeling of pinch-and-swell structures

    Science.gov (United States)

    Peters, Max; Berger, Alfons; Herwegh, Marco; Regenauer-Lieb, Klaus

    2016-04-01

    dominated deformation at relatively high extensional strains in the pinches. The numerical simulations indicate that viscosity weakening due to dissipated heat from grain size reduction marks the onset of localization, resulting in continuous necking of the layer. Interestingly, there exist multiple steady states, i.e. a first homogeneous state out of which localization arises, steady states of the stable end-member structure, expressed by homogeneous conditions in both pinches and swells, and in the surrounding matrix, the latter obeying a linear rheology. Based on our microstructural and numerical results, we suggest that the onset of localization represents a fundamental material bifurcation. This implies that the studied structures can be described as ductile instabilities. Finally, we discuss the profound role of the energy theory of localization described here, which allows deriving the paleo-deformation conditions, as well as fundamental material properties in a self-consistent manner. REFERENCES Herwegh, M., Poulet, T., Karrech, A. and Regenauer-Lieb, K. (2014): Journal of Geophysical Research 119, doi:10.1002/2013JB010701 Peters, M., Veveakis, M., Poulet, T., Karrech, A., Herwegh, M. and Regenauer-Lieb, K. (2015): Journal of Structural Geology 78, doi:10.1016/j.jsg.2015.06.005

  9. Swell impact on wind stress and atmospheric mixing in a regional coupled atmosphere-wave model

    DEFF Research Database (Denmark)

    Wu, Lichuan; Rutgersson, Anna; Sahlée, Erik

    2016-01-01

    Over the ocean, the atmospheric turbulence can be significantly affected by swell waves. Change in the atmospheric turbulence affects the wind stress and atmospheric mixing over swell waves. In this study, the influence of swell on atmospheric mixing and wind stress is introduced into an atmosphere......-neutral and unstable stratification conditions is introduced by changing the roughness length. Five year simulation results indicate that adding the swell influence on atmospheric mixing has limited influence, only slightly increasing the near-surface wind speed; in contrast, adding the swell influence on wind stress....... The influence varies with wave characteristics for different sea basins. Swell occurs infrequently in the studied area, and one could expect more influence in high-swell-frequency areas (i.e., low-latitude ocean). We conclude that the influence of swell on atmospheric mixing and wind stress should be considered...

  10. What Causes Ankle Swelling During Pregnancy - And What Can I do About it?

    Science.gov (United States)

    Healthy Lifestyle Pregnancy week by week What causes ankle swelling during pregnancy — and what can I do ... M.D. Various factors contribute to foot and ankle swelling during pregnancy. For starters, your body retains ...

  11. Tunable ion-swelling for nanopatterning of macroscopic surfaces: The role of proximity effects

    International Nuclear Information System (INIS)

    Highlights: ► Utilizing ion irradiation and nanosphere lithography to induce local swelling on Si. ► Pattern height and curvature were tailored by the mask and irradiation parameters. ► Proximity exposure effect calculations to predict the radial ion fluence distribution. ► Good agreement between AFM profiles and ion fluence distributions. ► Surface profiles were predicted for several particle shapes, sizes, and ion energies. - Abstract: Ordered surface nanopatterns with different spatial periods and various characters were prepared on silicon surfaces by masked ion irradiation utilizing the local ion-swelling effect. Langmuir–Blodgett (LB) monolayers of hexagonally arranged Stöber silica particles as nanomasks were applied on large area Si substrates during Ar + or Xe 2+ exposure with different fluences. We show that the height and curvature of surface swelling patterns can be tuned by appropriate selection of the particle diameter, ion energy, and ion fluence. It is also revealed that the ion beam-induced anisotropic deformation of the silica mask can be exploited to tailor the surface geometry. We point that, having knowledge on the diameters and average spacing between the silica particles as extrinsic beam spreading factors, and considering the lateral straggling of the bombarding ions in the mask and in the substrate material as intrinsic beam spreading factors, a simple model of the radial fluence distribution can be applied to predict the main features of irradiation-induced surface patterns. The role of proximity effects in the potential use of this easy, fast, wafer-scale nanofabrication method is discussed.

  12. Characterization of calcium, phosphate and peroxide interactions in activation of mitochondrial swelling using derivative of the swelling curves

    Czech Academy of Sciences Publication Activity Database

    Drahota, Zdeněk; Endlicher, R.; Staňková, P.; Rychtrmoc, D.; Milerová, Marie; Červinková, Z.

    2012-01-01

    Roč. 44, č. 3 (2012), s. 309-315 ISSN 0145-479X R&D Projects: GA MZd(CZ) NT12370 Grant - others:GA ČR(CZ) GP305/09/P145 Institutional support: RVO:67985823 Keywords : mitochondrial swelling * mitochondrial permeability transition pore * Calcium, phosphate and peroxide interactions Subject RIV: FG - Pediatrics Impact factor: 1.604, year: 2012

  13. Effect of titanium or/and aluminium on 1 MeV electron swelling of low chromium Fe-Cr10-Ni20-25 type alloys

    International Nuclear Information System (INIS)

    Seran, J.L.

    1985-10-01

    Simulation swelling results with 1 MeV electrons at 500 0 C and 600 0 C on many low chromium steels hardened in solid solution or by γ' phase precipitation by titanium or/and aluminium additions. These new steels, for some chemical compositions, may have a resistance to swelling upper than the classical reference materials such as 316 Ti type materials. The alloys hardened by precipitation and then highly doped in titanium and/or aluminium do not seem very propositions because cavity germination is important at medium temperatures. In the contrary, the under-stabilized steels are also to rule-out because their swelling speed is prohibitive. Between these two extremes, 10-25 alloys hardened in solid solution by some tenth per cent of titanium could be the most interesting one, at least at temperatures higher than 500 0 C [fr

  14. Hypoosmotic cell swelling as a novel mechanism for modulation of cloned HCN2 channels

    DEFF Research Database (Denmark)

    Calloe, Kirstine; Elmedyb, Pernille; Olesen, Søren-Peter

    2005-01-01

    with hypoosmotic media. This indicates that cell swelling and not a change in ionic strength of the media, caused the observed swelling-induced increase in current. The increase in HCN2 current induced by cell swelling could be abolished by cytochalasin D treatment, indicating that an intact F-actin cytoskeleton...

  15. Recent experimental and theoretical insights on the swelling of austenitic alloys

    International Nuclear Information System (INIS)

    Garner, F.A.; Wolfer, W.G.

    1983-01-01

    Once void nucleation subsides, the swelling rate of many austenitic alloys becomes rather insensitive to the variables that determine the duration of the transient regime of swelling. Models are presented which describe the roles of nickel, chromium and silicon in void nucleation. The relative insensitivity of steady-state swelling to temperature and composition is also discussed

  16. Recent studies on wind seas and swells in the Indian Ocean: A review

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; Rashmi, R.; Samiksha, S.V.; Aboobacker, V.M.

    , decrease in swell period and a common propagation direction (northwest) for wind seas and swells Also the swells generated at 40 degrees S, propagate in the north Indian Ocean, and enter in the Bay of Bengal than the Arabian Sea During fair weather season...

  17. The wettability and swelling of selected mucoadhesive polymers in simulated saliva and vaginal fluids.

    Science.gov (United States)

    Rojewska, M; Olejniczak-Rabinek, M; Bartkowiak, A; Snela, A; Prochaska, K; Lulek, J

    2017-08-01

    The surface properties play a particularly important role in the mucoadhesive drug delivery systems. In these formulations, the adsorption of polymer matrix to mucous membrane is limited by the wetting and swelling process of the polymer structure. Hence, the performance of mucoadhesive drug delivery systems made of polymeric materials depends on multiple factors, such as contact angle, surface free energy and water absorption rate. The aim of our study was to analyze the effect of model saliva and vaginal fluids on the wetting properties of selected mucoadhesive (Carbopol 974P NF, Noveon AA-1, HEC) and film-forming (Kollidon VA 64) polymers as well as their blends at the weight ratio 1:1 and 1:1:1, prepared in the form of discs. Surface properties of the discs were determined by measurements of advancing contact angle on the surface of polymers and their blends using the sessile drop method. The surface energy was determined by the OWRK method. Additionally, the mass swelling factor and hydration percentage of examined polymers and their blends in simulated biological fluids were evaluated. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Generalized Rate Theory for Void and Bubble Swelling and its Application to Delta-Plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Allen, P. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wall, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wolfer, W. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-04

    A rate theory for void and bubble swelling is derived that allows both vacancies and self-interstitial atoms to be generated by thermal activation at all sinks. In addition, they can also be produced by displacement damage from external and internal radiation. This generalized rate theory (GRT) is applied to swelling of gallium-stabilized δ-plutonium in which α-decay causes the displacement damage. Since the helium atoms produced also become trapped in vacancies, a distinction is made between empty and occupied vacancies. The growth of helium bubbles observed by transmission electron microscopy (TEM) in weapons-grade and in material enriched with Pu238 is analyzed, using different values for the formation energy of self-interstitial atoms (SIA) and two different sets of relaxation volumes for the vacancy and for the SIA. One set allows preferential capture of SIA at dislocations, while the other set gives equal preference to both vacancy and SIA. It is found that the helium bubble diameters observed are in better agreement with GRT predictions if no preferential capture occurs at dislocations. Therefore, helium bubbles in δ-plutonium will not evolve into voids. The helium density within the bubbles remains sufficiently high to cause thermal emission of SIA. Based on a helium density between two to three helium atoms per vacant site, the sum of formation and migration energies must be around 2.0 eV for SIA in δ-plutonium.

  19. SCROTAL SWELLING- EVALUATION BY HIGH FREQUENCY USG AND COLOUR DOPPLER STUDIES

    Directory of Open Access Journals (Sweden)

    Krishna Kumar Borah

    2017-01-01

    Full Text Available BACKGROUND The aim of the study is to- 1. Study ultrasonographic and colour Doppler patterns of different causes of scrotal swelling (masses. 2. Asses the role of high frequency real time USG in differentiating testicular and extra testicular masses. MATERIALS AND METHODS A hospital-based cross-sectional study of 100 cases of scrotal pathology were studied over a period of 1 year from 1 st August, 2008, to 31 st July, 2009, in the Department of Radiodiagnosis, Assam Medical College Hospital at Dibrugarh. All the patients were subjected to grey scale high resolutions USG of scrotum and then scrotal colour Doppler study. Sonographic imaging was performed with Phillips HD-11 real time scanner by using 2.5-5 MHz curvilinear probe and 10 MHz linear transducer. RESULTS Out of 100 cases of scrotal swelling- 97% were benign, 3% were malignant. Among the benign lesions, 82% cases were extra testicular, 7% intratesticular, 8% are both intra and extra testicular in origin. 100% of all malignant lesions were intratesticular. Of the benign lesion- 40% hydrocele, 26% inflammatory lesions, 5% hernia, 6% varicocele, 4% traumatic, 5% cases epididymal cyst, 2% cases torsion. CONCLUSION High resolution, high frequency US and colour Doppler study of scrotum had the advantages of being noninvasiveness, lack of ionising radiation, wide availability, cost effectiveness and repeatability. It is accurate in differentiating testicular ischaemia and torsion, solid and cystic, benign and malignant mass. It is highly sensitive in demonstrating varicocele.

  20. Mitigation of Voltage Swells by Static Series Compensator

    DEFF Research Database (Denmark)

    Awad, Hilmy; Blaabjerg, Frede

    2004-01-01

    is lower than a predetermined voltage level, the active power is employed to charge the ESC to this voltage level; 2) otherwise, the overvoltage protection of the SSC must operate. This paper also applies an overvoltage protection scheme based on a combination of a dc resistor with a chopper and the valves...... of the SSC. The design of the dc resistor is discussed. A 10 kV SSC experimental setup is exploited to carry out experiments in the case of balanced and unbalanced voltage swells at the grid side....

  1. DIAGNOSIS AND TREATMENT OF SCROTAL SWELLING IN ADULTS: OUR EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Rajkumar

    2016-01-01

    Full Text Available INTRODUCTION Scrotal swelling can present from early childhood to old age with the varying causes presenting widely across the age spectrum. The presentation can range from incidental finding to severe illness. A careful history and physical exam can distinguish from benign pathology like hydrocele to potentially morbid conditions like Fournier’s gangrene to life-threatening conditions like testicular cancer. In certain emergency conditions like torsion of testis, timely identification and early intervention can save testis. We present our experience in managing a wide range of scrotal pathologies at our institute.

  2. Effect of fusion burn cycle on first wall swelling

    International Nuclear Information System (INIS)

    Choi, Y.H.; Bement, A.L.; Russell, K.C.

    1976-01-01

    A mathematical simulation of first wall swelling has been performed for stainless steel under a hypothetical duty cycle of 50 sec burn, 50 sec cool. In most instances steady state nucleation conditions were not established during the burn cycle, thereby necessitating the use of transient nucleation theory. The effects of transmutation helium and of surface active impurities were modelled in an approximate way. Both kinds of impurity were found to give large increases in the void nucleation rate. Suggestions for refining and extending the calculations are also given

  3. Phenomenological theory of sintering and its application to swelling

    Directory of Open Access Journals (Sweden)

    Kornyushin Y.

    2004-01-01

    Full Text Available The general phenomenological theory of sintering, formulated by the author in 1998 is applied to the problem of swelling. Driving forces, caused by the presence of the evolution of heat in the volume of a sample (electric contact, hf, inductive heating or penetrating radiation, e.g., neutrons could be the sources of the heat in the bulk of a sample are considered. The influence of these driving forces on sintering, structure and properties is discussed. The role of mobile and immobile dislocations, grain boundaries, and pores is considered. Cycling and pulsing regimes of sintering are investigated.

  4. Kimura's Disease: A Rare Cause of Postauricular Swelling

    Directory of Open Access Journals (Sweden)

    Suman Kumar Das

    2017-04-01

    Full Text Available Introduction Kimura’s Disease is a chronic inflammatory disorder of lymph node which is very rare in Indian population. Case Report A 15 year old boy with multiple postauricular swelling for 18 months presenting in OPD and diagnosed having eosinophilia. Then excision biopsy was taken, which indicates Kimura’s Disease. Patient was treated with high dose of corticosteroid. Conclusion Kimura’s disease, though rare should be kept in mind for treating a patient with lymphadenopathy with eosinophilia or high IgE level, because it can spare the patient unnecessary invasive procedure.

  5. Effect of vacancy loops on swelling of metals under irradiation

    International Nuclear Information System (INIS)

    Golubov, S.I.

    1981-01-01

    Subsequent analysis of vacancy loops formation in metals under irradiation is carried out and effect of vacancy loops on vacancy porosity is studied. Expression for quasistationary function of vacancy loops distribution according to sizes taking into consideration two mechanisms of their initiation-cascade and fluctuational ones - is obtained. It is shown that rate of vacancy absorption and interstitials by vacancy loops in quasiequilibrium state is similar and depends only on summary length of loops, for its calculations the self-coordinated procedure is formulated. For the rate of metal swelling under irradiation obtained is the expression taking into consideration the presence of vacancy loops [ru

  6. Genital tuberculosis: A rare cause of vulvovaginal discharge and swelling

    Directory of Open Access Journals (Sweden)

    Malak Alhakeem

    2013-09-01

    Full Text Available Herein, we report a patient with vulvovaginal tuberculosis (TB presented with a vulvovaginal mass and vaginal discharge.The diagnosis was made by both histopathological examination of the excised specimen which was clinicallysuspected to be a malignant lesion and cervical smear culture positivity for Mycobacterium tuberculosis. The patientwas prescribed a full course of anti-tuberculous drugs. In this report, we discuss the genital TB and its gynecologicaleffects in the light of medical literature. J Microbiol Infect Dis 2013; 3(3: 140-142Key words: Genital tuberculosis, vulvovaginal swelling

  7. Swelling and sedimentation of bentonite clays in bulk and in slits: nuclear magnetic resonance spectroscopy and imaging studies

    International Nuclear Information System (INIS)

    Dvinskikh, S.V.; Furo, I.; Neretnieks, I.

    2010-01-01

    Document available in extended abstract form only. Compacted bentonite clay is currently attracting attention as a promising 'self-sealing' buffer material to build in-ground barriers for the encapsulation of radioactive waste. It is expected to fill up the space between waste canister and surrounding ground by swelling and thus delay flow and migration from the host rock to the canister. Evaluation and understanding of the swelling properties of pre-compacted bentonite are of uttermost importance for designing such buffers. The major goal of our studies was to provide, in a non-invasive manner, a quantitative measure of bentonite distribution in extended samples during different physical processes in an aqueous environment such as swelling, dissolution, and sedimentation on the time scale from minutes to years. The propagation of the swelling front during clay expansion depending on the geometry of the confining space was also studied. To characterize the state of colloids that form after/during clay swelling the water self-diffusion coefficient was measured on a spatially resolved manner. The distribution and displacement within the bentonite systems of foreign particles, either natural ones (sand or quartz) or artificially admixed model particles of controlled size were also monitored. Both natural montmorillonites and purified and ion-exchanged montmorillonite clays were investigated. The primary variables were clay composition and water ionic strength. Magnetic resonance imaging and nuclear magnetic resonance spectroscopy were adapted and used as main experimental techniques. With this approach, spatially resolved movement of the clay/water interface as well as clay particle distributions in gel phase can be monitored. Bulk samples with swelling in a vertical tube and in a horizontal channel were investigated and clay content distribution profiles in the concentration range over five orders of magnitude and with sub-millimetre spatial resolution were

  8. Influence of applied stress on swelling behavior in Type 304 stainless steel

    International Nuclear Information System (INIS)

    Igata, N.; Fujihira, T.; Kohno, Y.; Tsunakawa, M.

    1984-01-01

    The swelling behavior of Type 304 stainless steel during stress application was investigated by means of electron irradiation using a high-voltage electron microscope (HVEM). The dose dependence of swelling under stress is similar to the linearafter-incubation swelling scheme of other electron irradiation studies. The effect of applied stress on the swelling characteristics appeared through the control of incubation regime of swelling rather than of the swelling rate. The incubation dose first increases, then decreases, and increases again with increasing applied stress. The prominent finding in this study, based on the advantage of HVEM in situ observation, is that the saturated void density is equal to the number density of interstitial dislocation loops observed in the early stage of irradiation. Essentially, applied stress affects the loop nucleation process. The dislocation loop density then affects the incubation dose of swelling through its control of dislocation behavior and the saturation dose of dislocation density

  9. Development and validation of constitutive equation of HBS irradiation swelling considering hydrostatic pressure

    International Nuclear Information System (INIS)

    Gao Lijun; Jiang Shengyao; Yu Jiyang; Chen Bingde; Xiao Zhong

    2014-01-01

    The mechanism of hydrostatic pressure affecting the irradiation swelling of UO 2 high burnup structure was analyzed. Three basic assumptions used to develop the constitutive equation of irradiation swelling were made accordingly. It is concluded that hydrostatic pressure imposes an important impact on irradiation swelling mainly through compressing the UO 2 high burnup structure pores. Based on the already developed correlation of the irradiation swelling of UO 2 high burnup structure, pore shrinkage due to the application of hydrostatic pressure and thus the reduction of irradiation swelling of UO 2 high burnup structure were determined quantitatively, and the constitutive equation of irradiation swelling of UO 2 high burnup structure considering the hydrostatic pressure was constructed successfully. The constitutive equation is validated using available irradiation swelling data of UO 2 high burnup structure, which demonstrates its reasonability. (authors)

  10. Evaluation of the swelling behaviour of iota-carrageenan in monolithic matrix tablets.

    Science.gov (United States)

    Kelemen, András; Buchholcz, Gyula; Sovány, Tamás; Pintye-Hódi, Klára

    2015-08-10

    The swelling properties of monolithic matrix tablets containing iota-carrageenan were studied at different pH values, with measurements of the swelling force and characterization of the profile of the swelling curve. The swelling force meter was linked to a PC by an RS232 cable and the measured data were evaluated with self-developed software. The monitor displayed the swelling force vs. time curve with the important parameters, which could be fitted with an Analysis menu. In the case of iota-carrageenan matrix tablets, it was concluded that the pH and the pressure did not influence the swelling process, and the first section of the swelling curve could be fitted by the Korsmeyer-Peppas equation. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Effect of pressure on the transient swelling rate of oxide fuel

    International Nuclear Information System (INIS)

    Gruber, E.E.

    1982-04-01

    An analysis of the transient swelling rate of oxide fuel, based on fission-gas bubble conditions calculated with the FRAS3 code, has been developed and implemented in the code. The need for this capability arises in the coupling of the FRAS3 fission-gas analysis code to the FPIN fuel-pin mechanics code. An efficient means of closely coupling the calculations of swelling strains and stresses between the modules is required. The present analysis provides parameters that allow the FPIN calculation to proceed through a fairly large time step, using estimated swelling rates, to calculate the stresses. These stress values can then be applied in the FRAS3 detailed calculation to refine the swelling calculation, and to provide new values for the parameters to estimate the swelling in the next time step. The swelling rates were calculated for two representative transients and used to estimate swelling over a short time period for various stress levels

  12. Shrinkage/swelling of compacted clayey loose and dense soils

    Science.gov (United States)

    Nowamooz, Hossein; Masrouri, Farimah

    2009-11-01

    This Note presents an experimental study performed on expansive compacted loose and dense samples using osmotic oedometers. Several successive wetting and drying cycles were applied in a suction range between 0 and 8 MPa under different values of constant net vertical stress (15, 30, and 60 kPa). During the suction cycles, the dense samples showed cumulative swelling strains, while the loose samples showed volumetric shrinkage accumulation. At the end of the suction cycles, the volumetric strains converged to an equilibrium stage that indicated elastic behavior of the swelling soil for any further hydraulic variations. At this stage, the compression curves for the studied soil at the different imposed suctions (0, 2, and 8 MPa) converged towards the saturated state curve for the high applied vertical stresses. We defined this pressure as the saturation stress(P). The compression curves provided sufficient data to examine the soil mechanical behavior at the equilibrium stage. To cite this article: H. Nowamooz, F. Masrouri, C. R. Mecanique 337 (2009).

  13. Hereditary Angioedema Attacks: Local Swelling at Multiple Sites.

    Science.gov (United States)

    Hofman, Zonne L M; Relan, Anurag; Hack, C Erik

    2016-02-01

    Hereditary angioedema (HAE) patients experience recurrent local swelling in various parts of the body including painful swelling of the intestine and life-threatening laryngeal oedema. Most HAE literature is about attacks located in one anatomical site, though it is mentioned that HAE attacks may also involve multiple anatomical sites simultaneously. A detailed description of such multi-location attacks is currently lacking. This study investigated the occurrence, severity and clinical course of HAE attacks with multiple anatomical locations. HAE patients included in a clinical database of recombinant human C1-inhibitor (rhC1INH) studies were evaluated. Visual analog scale scores filled out by the patients for various symptoms at various locations and investigator symptoms scores during the attack were analysed. Data of 219 eligible attacks in 119 patients was analysed. Thirty-three patients (28%) had symptoms at multiple locations in anatomically unrelated regions at the same time during their first attack. Up to five simultaneously affected locations were reported. The observation that severe HAE attacks often affect multiple sites in the body suggests that HAE symptoms result from a systemic rather than from a local process as is currently believed.

  14. Textureless Macula Swelling Detection with Multiple Retinal Fundus Images

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Tobin Jr, Kenneth William [ORNL; Grisan, Enrico [University of Padua, Padua, Italy; Favaro, Paolo [Heriot-Watt University, Edinburgh; Ruggeri, Alfredo [University of Padua, Padua, Italy; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Retinal fundus images acquired with non-mydriatic digital fundus cameras are a versatile tool for the diagnosis of various retinal diseases. Because of the ease of use of newer camera models and their relatively low cost, these cameras can be employed by operators with limited training for telemedicine or Point-of-Care applications. We propose a novel technique that uses uncalibrated multiple-view fundus images to analyse the swelling of the macula. This innovation enables the detection and quantitative measurement of swollen areas by remote ophthalmologists. This capability is not available with a single image and prone to error with stereo fundus cameras. We also present automatic algorithms to measure features from the reconstructed image which are useful in Point-of-Care automated diagnosis of early macular edema, e.g., before the appearance of exudation. The technique presented is divided into three parts: first, a preprocessing technique simultaneously enhances the dark microstructures of the macula and equalises the image; second, all available views are registered using non-morphological sparse features; finally, a dense pyramidal optical flow is calculated for all the images and statistically combined to build a naiveheight- map of the macula. Results are presented on three sets of synthetic images and two sets of real world images. These preliminary tests show the ability to infer a minimum swelling of 300 microns and to correlate the reconstruction with the swollen location.

  15. Unusual presentation of ulcerative postauricular swelling as sebaceous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Prem Chand

    2016-01-01

    Full Text Available Sebaceous glands have high concentration over head and neck region. Despite high concentration, sebaceous cell adenoma and carcinomas are infrequent. Sebaceous cell carcinoma is an uncommon, cutaneous aggressive tumor arising from the sebaceous glands and seen almost exclusively on the eyelids (75%. It accounts for just 0.2-0.7% of all eyelid tumors in the USA and very few cases that have originated in areas other than the eyelids have been reported. A 67-year-old male presented with swelling (3 cm Χ 4 cm, on the right postauricular region, since about 1-month. The swelling became ulcerative and associated with progressive tinnitus and hoarseness of voice. The patient was investigated. Fine-needle aspiration cytology suggested sebaceous cell carcinoma. Then excision biopsy was done, and histopathological examination of excised tissue confirmed the diagnosis. Extraorbital sebaceous cell carcinoma is an aggressive and invasive malignancy. It clinically mimics other diseases and is difficult to diagnose. Hence, an accurate and prompt diagnosis is crucial because of its fulminant course, serious associations with Muir-Torre syndrome and high potential for regional and distant metastasis.

  16. Mechanical Blepharoptosis and Eyelid Swelling Caused by Silicone Oil

    Directory of Open Access Journals (Sweden)

    Thabit A. Mustafa

    2009-01-01

    Full Text Available The purpose of this article is to report a case of upper eyelid mechanical ptosis caused by silicone oil migration in a Jordanian patient after pars plana vitrectomy and intraocular silicone oil injection. A 20-year-old male patient was referred to the oculoplastic clinic for the management of a left upper eyelid swelling and complete ptosis that developed 12 years after pars plana vitrectomy and silicone oil placement for retinal detachment secondary to perforating eye injury. Eye examination showed upper eyelid swelling and a complete ptosis induced by the weight of inflammatory tissue and silicone oil, as proved by histopathologic examination. We presumed that silicone oil had leaked through the pars plana vitrectomy ports or through a subtle traumatic perforation of the posterior segment, which might have been aggravated by increased intra-ocular pressure postoperatively. In conclusion, mechanical ptosis caused by silicone oil migration after retinal detachment surgery is rare and this is one of the few reports in the literature.

  17. Segmentation of knee injury swelling on infrared images

    Science.gov (United States)

    Puentes, John; Langet, Hélène; Herry, Christophe; Frize, Monique

    2011-03-01

    Interpretation of medical infrared images is complex due to thermal noise, absence of texture, and small temperature differences in pathological zones. Acute inflammatory response is a characteristic symptom of some knee injuries like anterior cruciate ligament sprains, muscle or tendons strains, and meniscus tear. Whereas artificial coloring of the original grey level images may allow to visually assess the extent inflammation in the area, their automated segmentation remains a challenging problem. This paper presents a hybrid segmentation algorithm to evaluate the extent of inflammation after knee injury, in terms of temperature variations and surface shape. It is based on the intersection of rapid color segmentation and homogeneous region segmentation, to which a Laplacian of a Gaussian filter is applied. While rapid color segmentation enables to properly detect the observed core of swollen area, homogeneous region segmentation identifies possible inflammation zones, combining homogeneous grey level and hue area segmentation. The hybrid segmentation algorithm compares the potential inflammation regions partially detected by each method to identify overlapping areas. Noise filtering and edge segmentation are then applied to common zones in order to segment the swelling surfaces of the injury. Experimental results on images of a patient with anterior cruciate ligament sprain show the improved performance of the hybrid algorithm with respect to its separated components. The main contribution of this work is a meaningful automatic segmentation of abnormal skin temperature variations on infrared thermography images of knee injury swelling.

  18. Simultaneous measurement of CO2 sorption and swelling of phosphate-based ionic liquid

    Directory of Open Access Journals (Sweden)

    Junfeng Wang

    2016-10-01

    Full Text Available The development of alternative CO2 capture solvents such as ionic liquids (ILs and nanoparticle organic hybrid materials (NOHMs have provided interesting options for CO2 capture. In this study, CO2 interactions with 1,3-dimethylimidazolium dimethylphosphate ([MMIM]DMP, 1-ethyl-3-methylimidazolium dimethylphosphate ([EMIM]DMP and 1-ethyl-3-methylimidazolium diethylphosphate ([EMIM]DEP that contain inorganic ester groups based on phosphate, were investigated using ATR FT-IR spectroscopy. CO2-induced swelling, CO2 diffusivity and CO2 capture capacity were simultaneously measured to identify CO2 capture mechanisms, kinetics and diffusion behaviors as a function of the alkyl chain length of the cation. Henry's law constants of CO2 were found to be in the range of 4–11 MPa, which is in agreement with those reported in other studies. Keywords: CO2 capture, ATR FT-IR spectroscopy, Ionic liquids, Mechanism, Diffusivity

  19. Chronic swelling from entrapment of acrylic resin in a surgical extraction site

    Directory of Open Access Journals (Sweden)

    Weiting Ho

    2010-01-01

    Full Text Available When acrylic resin is inadvertently embedded in oral tissue, it can result in a pronounced chronic inflammatory response. This report describes a case in which temporary crown and bridge resin was forced into a surgical extraction site after the two adjacent teeth were prepared for a bridge immediately following extraction of a maxillary premolar. The patient experienced swelling at the extraction site over a ten month period despite treatment with antibiotics and anti-inflammatory drugs. After detection and removal of the foreign body, the symptoms resolved. The episode contributed to periodontal bone loss around an adjacent tooth. While morbidity of this nature is rare, this case reinforces the need to investigate persistent signs of inflammation and account for dental materials that are lost during the course of treatment.

  20. Variations in swells along Eastern Arabian Sea during the summer monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Johnson, G.; SanilKumar, V.; Sanjiv, P.C.; Singh, J.; Pednekar, P.S.; AshokKumar, K.; Dora, G.U.; Gowthaman, R.

    the average spring tidal range is about 1.8 m and the neap tidal range is 0.9 m. 3. Materials and Methods The waves at 3 locations (Table 1) along the west coast of India in the eastern Arabian Sea were measured using the Datawell directional waverider... and that due to wind sea was 0.9 to 1.1 m. Hm0 up to 4.7 m and Hmax up to 7.4 m was recorded during the meas- urement period. Hm0 was more than 2 m during 40, 50 and 66% of time at Honnavar, Ratnagiri and Muldwarka. Percentage of swell energy in the total...

  1. The role of grain size in He bubble formation: Implications for swelling resistance

    Science.gov (United States)

    El-Atwani, O.; Nathaniel, J. E.; Leff, A. C.; Muntifering, B. R.; Baldwin, J. K.; Hattar, K.; Taheri, M. L.

    2017-02-01

    Nanocrystalline metals are postulated as radiation resistant materials due to their high defect and particle (e.g. Helium) sink density. Here, the performance of nanocrystalline iron films is investigated in-situ in a transmission electron microscope (TEM) using He irradiation at 700 K. Automated crystal orientation mapping is used in concert with in-situ TEM to explore the role of grain orientation and grain boundary character on bubble density trends. Bubble density as a function of three key grain size regimes is demonstrated. While the overall trend revealed an increase in bubble density up to a saturation value, grains with areas ranging from 3000 to 7500 nm2 show a scattered distribution. An extrapolated swelling resistance based on bubble size and areal density indicated that grains with sizes less than 2000 nm2 possess the greatest apparent resistance. Moreover, denuded zones are found to be independent of grain size, grain orientation, and grain boundary misorientation angle.

  2. Non-monotonic swelling of surface grafted hydrogels induced by pH and/or salt concentration

    Science.gov (United States)

    Longo, Gabriel S.; Olvera de la Cruz, Monica; Szleifer, I.

    2014-09-01

    We use a molecular theory to study the thermodynamics of a weak-polyacid hydrogel film that is chemically grafted to a solid surface. We investigate the response of the material to changes in the pH and salt concentration of the buffer solution. Our results show that the pH-triggered swelling of the hydrogel film has a non-monotonic dependence on the acidity of the bath solution. At most salt concentrations, the thickness of the hydrogel film presents a maximum when the pH of the solution is increased from acidic values. The quantitative details of such swelling behavior, which is not observed when the film is physically deposited on the surface, depend on the molecular architecture of the polymer network. This swelling-deswelling transition is the consequence of the complex interplay between the chemical free energy (acid-base equilibrium), the electrostatic repulsions between charged monomers, which are both modulated by the absorption of ions, and the ability of the polymer network to regulate charge and control its volume (molecular organization). In the absence of such competition, for example, for high salt concentrations, the film swells monotonically with increasing pH. A deswelling-swelling transition is similarly predicted as a function of the salt concentration at intermediate pH values. This reentrant behavior, which is due to the coupling between charge regulation and the two opposing effects triggered by salt concentration (screening electrostatic interactions and charging/discharging the acid groups), is similar to that found in end-grafted weak polyelectrolyte layers. Understanding how to control the response of the material to different stimuli, in terms of its molecular structure and local chemical composition, can help the targeted design of applications with extended functionality. We describe the response of the material to an applied pressure and an electric potential. We present profiles that outline the local chemical composition of the

  3. Swelling analysis of austenitic stainless steels by means of ion irradiation and kinetic modeling

    International Nuclear Information System (INIS)

    Kohyama, Akira; Donomae, Takako

    1999-03-01

    The influences of irradiation environment on the swelling behavior of austenitic stainless steel has been studied, to aid understanding the origin of the difference in swelling response of PNC316 stainless steel in fuel-pin environment and in materials irradiation capsules, in terms of irradiation conditions, damage mechanism and material conditions. This work focused on the theoretical investigation of the influence of temperature variation on microstructural development of austenitic stainless steels during irradiation, using a kinetic rate theory model. A modeling and calculation on non-steady irradiation effects were first carried out. A fully dynamic model of point defect evolution and extended defect development, which accounts for cascade damage, was developed and successfully applied to simulate the interstitial loop evolution in low temperature regimes. The influence of cascade interstitial clustering on dislocation loop formation has also been assessed. The establishment of a basis for general assessment of non-steady irradiation effects in austenitic stainless steels was advanced. The developed model was applied to evaluate the influences of temperature variation in formerly carried out CMIR and FFTF/MFA-1 FBR irradiation experiments. The results suggested the gradual approach of microstructural features to equilibrium states in all the temperature variation conditions and no sign of anomalous behavior was noted. On the other hand, there is the influence of temperature variation on microstructural development under the neutron irradiation, like CMIR. So there are some possibilities of the work of mechanism which is not taken care on this model, for example the effect of the precipitate behavior which is sensitive to irradiation temperature. (author)

  4. Eddy current sensor for in-situ monitoring of swelling of Li-ion prismatic cells

    Science.gov (United States)

    Plotnikov, Yuri; Karp, Jason; Knobloch, Aaron; Kapusta, Chris; Lin, David

    2015-03-01

    In-situ monitoring an on-board rechargeable battery in hybrid cars can be used to ensure a long operating life of the battery and safe operation of the vehicle. Intercalations of ions in the electrode material during charge and discharge of a Lithium Ion battery cause periodic stress and strain of the electrode materials that can ultimately lead to fatigue resulting in capacity loss and potential battery failure. Currently this process is not monitored directly on the cells. This work is focused on development technologies that would quantify battery swelling and provide in-situ monitoring for onboard vehicle applications. Several rounds of tests have been performed to spatially characterize cell expansion of a 5 Ah cell with a nickel/manganese/cobalt-oxide cathode (Sanyo, Japan) used by Ford in their Fusion HEV battery pack. A collaborative team of researchers from GE and the University of Michigan has characterized the free expansion of these cells to be in the range of 100×125 microns (1% of total cell thickness) at the center point of the cell. GE proposed to use a thin eddy current (EC) coil to monitor these expansions on the cells while inside the package. The photolithography manufacturing process previously developed for EC arrays for detecting cracks in aircraft engine components was used to build test coils for gap monitoring. These sensors are thin enough to be placed safely between neighboring cells and capable of monitoring small variations in the gap between the cells. Preliminary investigations showed that these coils can be less than 100 micron thick and have sufficient sensitivity in a range from 0 to 2 mm. Laboratory tests revealed good correlation between EC and optical gap measurements in the desired range. Further technology development could lead to establishing a sensor network for a low cost solution for the in-situ monitoring of cell swelling during battery operation.

  5. Experimental study of swelling of irradiated solid methane during annealing

    International Nuclear Information System (INIS)

    Shabalin, E.; Fedorov, A.; Kulagin, E.; Kulikov, S.; Melikhov, V.; Shabalin, D.

    2008-01-01

    Solid methane is still widely in use at pulsed neutron sources due to its excellent neutronic performance (IPNS, KENS, Second Target Station at ISIS), notwithstanding poor radiation properties. One of the specific problems is radiolytic hydrogen gas pressure on the walls of a methane chamber during annealing of methane. In this paper results of an experimental study of this phenomenon under fast neutron irradiation with the help of a specially made low temperature irradiation rig at the IBR-2 pulsed reactor are presented. The peak pressure on the wall of the experimental capsule during heating of a sample irradiated at 23-35 K appears to have a maximum of 2.7 MPa at an absorbed dose 20 MGy and then falls down with higher doses. The pressure always reached its peak value at the temperature range 72-79 K. Generally, three phases of methane swelling during heating can be distinguished, each characterized by a proper rate and intensity.

  6.  Soft Tissue Swelling at the Subscapular Region

    Directory of Open Access Journals (Sweden)

    Masoud Al Kindi

    2012-03-01

    Full Text Available A 38-year-old female presented with a longstanding painless swelling overlying the scapula on the right side and has been gradually increasing in size with occasional episodes of pain radiating to the right arm. The clinical diagnosis was a soft tissue tumor. MRI was reported as suggestive of irregular fibro-fatty tissue with muscular infiltration and inflammation. Fine needle aspiration (FNA retrieved a paucicellular aspirate with a few clusters of adipocytes. The diagnosis was a lipomatous lesion and excision was advised for histopathological examination. The intraoperative findings showed the tumor located deep into the rhomboids and latissimus dorsi and extending deep into the right scapula. The excised specimen was sent for histopathological examination. 

  7. MRI estimation of extraocular muscle swelling in dysthyroid ophthalmopathy

    International Nuclear Information System (INIS)

    Watanabe, Yoshihiro; Kakisu, Yonetsugu; Hatakeyama, Masayuki; Asanagi, Kaoru

    1988-01-01

    The thickness and width of superior, inferior and medial rectus muscles were measured via T1-weighted coronal images using a 0.5 T superconducting MRI (magnetic resonance imaging) system in 10 patients with dysthyroid ophthalmopathy and 27 normal orbits. Lateral rectus muscles were not measured because the partial volume effect obscured their contours. Patients were divided into 3 groups according to the severity of ophthalmopathy. Group A had no ophthalmopathy, group B had corneal involvement or restricted eye movement, group C had optic nerve involvement. Mean muscle thickness increased in the order A, B and C. Mean rectus muscle width was normal in group A, but dramatically increased in group C, results suggesting that swelling of the extraocular muscles is a characteristic pathologic change in dysthyroid ophthalmopathy. It is concluded that MRI is a safe and useful method of evaluating the severity of and prognosing dysthyroid ophthalmopathy. (author)

  8. Ethanol-induced swelling in neonatal rat primary astrocyte cultures.

    Science.gov (United States)

    Aschner, M; Allen, J W; Mutkus, L A; Cao, C

    2001-05-11

    We tested the hypothesis that astrocytes swell in response to ethanol (EtOH) exposure. The experimental approach consisted of an electrical impedance method designed to measure cell volume. In chronic experiments, EtOH (100 mM) was added to the culture media for 1, 3, or 7 days. The cells were subsequently exposed for 15 min to isotonic buffer (122 mM NaCl) also containing 100 mM EtOH. Subsequently, the cells were washed and exposed to hypotonic buffer (112 mM NaCl) containing 100 mM mannitol. Chronic exposure to EtOH led to a marked increase in cell volume compared with control cells. Specific anion cotransport blockers, such as SITS, DIDS, furosemide, or bumetanide, when simultaneously added with EtOH to hyponatremic buffer, failed to reverse the EtOH-induced effect on swelling. In acute experiments, confluent neonatal rat primary astrocyte cultures were exposed to isotonic media (122 mM NaCl) for 15 min, followed by 45-min exposure to hypotonic media (112 mM NaCl, mimicking in vivo hyponatremic conditions associated with EtOH withdrawal) in the presence of 0-100 mM EtOH. This exposure led to a concentration-dependent increase in cell volume. Combined, these studies suggest that astrocytes exposed to EtOH accumulate compensatory organic solutes to maintain cell volume, and that in response to hyponatremia and EtOH withdrawal their volume increases to a greater extent than in cells exposed to hyponatremia alone. Furthermore, the changes associated with EtOH are osmotic in nature, and they are not reversed by anion cotransport blockers.

  9. Tamoxifen does not inhibit the swell activated chloride channel in human neutrophils during the respiratory burst.

    Science.gov (United States)

    Ahluwalia, Jatinder

    2008-10-31

    Effective functioning of neutrophils relies upon electron translocation through the NADPH oxidase (NOX). The electron current generated (I(e)) by the neutrophil NADPH oxidase is electrogenic and rapidly depolarises the membrane potential in activated human neutrophils. Swelling activated chloride channels have been demonstrated in part to counteract the depolarisation generated by the NADPH oxidase I(e). In the present study, the effects of inhibitors of swell activated chloride channels on ROS production and on the swelling activated chloride conductance was investigated in activated human neutrophils. Tamoxifen (10 microM), a specific inhibitor for swell activated chloride channels in neutrophils, completely inhibited both the PMA and FMLP stimulated respiratory burst. This inhibition of the neutrophil respiratory burst was not due to the blocking effect of tamoxifen on the swelling activated chloride conductance in these cells. These results demonstrate that a tamoxifen insensitive swell activated chloride channel has important significance during the neutrophil respiratory burst.

  10. Can radial gradients of swelling and of mechanical properties create extra deformation of fast fuel elements

    International Nuclear Information System (INIS)

    Lemoine, Patrick; Boutard, Jean-Louis

    1981-08-01

    The temperature gradient inside the cladding causes swelling gradients and irradiation creep modulus gradient at a temperature higher than 500 0 C (at least for steel 316). Swelling contribution to an increase in cladding length and diameter are equal to the mean swelling, if variations of mechanical properties with temperature are neglected. If mechanical property gradient are taken into account the solution of the problem is obtained by a classical analytic calculation with hypothesis on one dimension deformations and constant stress. In this case swelling contribution is different to the mean swelling. An additional term can be evaluated with the following assumptions: the tube is thin and swelling gradient and irradiation creep are constant, as but extra deformations are low [fr

  11. Improved swelling resistance for PCA austenitic stainless steel under HFIR irradiation through microstructural control

    International Nuclear Information System (INIS)

    Maziasz, P.J.; Braski, D.N.

    1983-01-01

    Six microstructural variants of Prime Candidate Alloy (PCA) were evaluated for swelling resistance during HFIR irradiation, together with several heats of type 316 stainless steel (316). Swelling was negligible in all the steels at 300 0 C after approx. 44 dpa. At 500 to 600 0 C 25%-cold-worked PCA showed better void swelling resistance than type 316 at approx. 44 dpa. There was less swelling variability among alloys at 400 0 C, but again 25%-cold-worked PCA was the best. Microstructurally, swelling resistance correlated with development of fine, stable bubbles whereas high swelling was due to coarser distributions of bubbles becoming unstable and converting to voids (bias-driven cavities)

  12. Swelling of Fe-Mn and Fe-Cr-Mn alloys at high neutron fluence

    International Nuclear Information System (INIS)

    Garner, F.A.; Brager, H.R.

    1986-06-01

    Swelling data on neutron-irradiated simple Fe-Cr-Mn and Fe-Mn alloys, as well as commercial Fe-Cr-Mn base alloys are now becoming available at exposure levels approaching 50 dpa. The swelling rate decreases from the ∼1%/dpa found at lower exposures, probably due to the extensive formation of ferritic phases. As expected, commercial alloys swell less than the simple alloys

  13. A SIPA-based theory of irradiation creep in the low swelling rate regime

    International Nuclear Information System (INIS)

    Garner, F.A.; Woo, C.H.

    1991-11-01

    A model is presented which describes the major facets of the relationships between irradiation creep, void swelling and applied stress. The increasing degree of anisotropy in distribution of dislocation Burger's vectors with stress level plays a major role in this model. Although bcc metals are known to creep and swell at lower rates than fcc metals, it is predicted that the creep-swelling coupling coefficient is actually larger

  14. Guest-responsive reversible swelling and enhanced fluorescence in a super-absorbent, dynamic microporous polymer.

    Science.gov (United States)

    Rao, K Venkata; Mohapatra, Sudip; Maji, Tapas Kumar; George, Subi J

    2012-04-10

    A swell idea! The guest-responsive reversible swelling and fluorescence enhancement of a dynamic, microporous polymer network is presented. Guest-induced breathing of hydrophobic pores imparts multi-functional properties, such as super-absorbency, phase-selective swelling of oil from water and encapsulation of C(60) (see figure), to this soft micro-porous organic polymer. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Corticosteroid transdermal delivery to target swelling, edema and inflammation following facial rejuvenation procedures

    Directory of Open Access Journals (Sweden)

    Iannitti T

    2013-09-01

    Full Text Available T Iannitti,1,2 V Rottigni,2,3 B Palmieri2,31School of Biomedical Sciences, University of Leeds, Leeds, UK; 2Poliambulatorio del Secondo Parere, Modena, Italy; 3Department of General Surgery and Surgical Specialties, University of Modena and Reggio Emilia Medical School, Surgical Clinic, Modena, ItalyBackground and aim: The use of transdermal therapeutic systems has spread worldwide since they allow effective local drug delivery. In the present study, we investigated the efficacy and safety of a new betamethasone valerate medicated plaster (Betesil® to manage facial swelling, edema, inflammation, ecchymosis, and hematoma, when applied immediately after a facial rejuvenation procedure.Materials and methods: We applied the plaster to the skin of 20 healthy patients for 12 hours immediately after hyaluronic acid-based procedure performed with the aim of erasing facial wrinkles of perioral and nasolabial folds and improving chin and eye contour. A further 20 patients underwent the same cosmetic procedure, but they were treated with an aescin 10% cream (applied immediately after the procedure, in the evening, and the morning after and served as control group.Results: Betesil® application resulted in a significant improvement in swelling/edema/inflammation score, if compared with aescin 10% cream (P < 0.01. As for facial ecchymosis and hematoma around the needle injection track, only two patients in the active treatment group displayed minimal ecchymosis and hematoma. In the control group, two patients presented minimal ecchymosis and three slight hematoma. However, using the ecchymosis/hematoma score, no significant difference between Betesil® and aescin 10% cream groups was observed. Patients’ satisfaction was significantly higher among subjects receiving Betesil®, if compared to patients receiving aescin 10% cream (P < 0.01.Conclusion: The present study supports the use of Betesil® plaster immediately after facial cosmetic procedures in order

  16. Improved swelling resistance for PCA austenitic stainless steel under HFIR irradiation through microstructural control

    International Nuclear Information System (INIS)

    Maziasz, P.J.; Braski, D.N.

    1984-01-01

    Swelling evaluation of PCA variants and 20%-cold-worked (N-Lot) type 316 stainless steel (CW 316) at 300 to 600 0 C was extended to 44 dpa. Swelling was negligible in all the steels at 300 0 C after approx. 44 dpa. At 500 to 600 0 C 25%-cold-worked PCA showed better void swelling resistance than type 316 at approx. 44 dpa. There was less swelling variation among alloys at 400 0 C, but again 25%-cold-worked PCA was the best

  17. Generation of Continental Rifts, Basins and Swells by Lithosphere Instabilities

    Science.gov (United States)

    Milelli, L.; Fourel, L.; Jaupart, C. P.

    2012-12-01

    Domal uplifts, volcanism, basin formation and rifting have often struck the same continent in different areas at the same time. Their characteristics and orientations are difficult to reconcile with mantle convection or tectonic forces and suggest a driving mechanism that is intrinsic to the continent. The rifts seem to develop preferentially at high angles to the edge of the continent whereas swells and basins seem confined to the interior. Another intriguing geometrical feature is that the rifts often branch out in complicated patterns at their landward end. In Western Africa, for example, magmatic activity currently occurs in a number of uplifted areas including the peculiar Cameroon Volcanic Line that stretches away from the continental margin over about 1000 km. Magmatic and volcanic activity has been sustained along this line for 70 My with no age progression. The mantle upwelling that feeds the volcanoes is not affected by absolute plate motions and hence is attached to the continent. The Cameroon Volcanic Line extends to the Biu swell to the North and the Jos plateau to the West defining a striking Y-shaped pattern. This structure segues into several volcanic domes including the Air, the Hoggar, the Darfur, the Tibesti and the Haruj domes towards the Mediterranean coast. Another example is provided by North America, where the late Proterozoic-early Ordovician saw the formation of four major basins, the Michigan, Illinois, Williston and Hudson Bay, as well as of major rifts in southern Oklahoma and the Mississipi Valley within a short time interval. At the same time, a series of uplifts developed, such as the Ozark and Nashville domes. Motivated by these observations, we have sought an explanation in the continental lithosphere itself. We describe a new type of convective instability at the base of the lithosphere that leads to a remarkable spatial pattern at the scale of an entire continent. We carried out fluid mechanics laboratory experiments on buoyant

  18. Magnetic relaxation--coal swelling, extraction, pore size. Technical progress report, October 1, 1991--December 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Doetschman, D.C.

    1991-12-31

    The grant activities during this period fall into four categories: (1) Completion of preparatory work, (2) Procedure refinement and actual preparation of whole coal, coal residue, coal extract and swelled coal samples for NMR studies, (3) Related studies of coal photolysis that employ materials from preliminary extractions and that examine the u.v.-visible and mass spectra of the extracts and (4) Continued investigations of the pulsed EPR characteristics of the whole coal samples that were prepared in the first quarter of the grant.

  19. Modification of SRIM-calculated dose and injected ion profiles due to sputtering, injected ion buildup and void swelling

    International Nuclear Information System (INIS)

    Wang, Jing; Toloczko, Mychailo B.; Bailey, Nathan; Garner, Frank A.; Gigax, Jonathan; Shao, Lin

    2016-01-01

    In radiation effects on materials utilizing self-ion irradiations, it is necessary to calculate the local displacement damage level and ion injection profile because of the short distance that self-ions travel in a material and because of the strong variation of displacement rate with depth in a specimen. The most frequently used tool for this is the software package called Stopping and Range of Ions in Matter (SRIM). A SRIM-calculated depth-dependent dose level is usually determined under the implicit assumption that the target does not undergo any significant changes in volume during the process, in particular SRIM ignores the effect of sputtering, injected ions, and void swelling on the redistribution of the dose and injected ion profiles. This approach become increasingly invalid as the ion fluence reaches ever higher levels, especially for low energy ion irradiations. The original surface is not maintained due to sputter-induced erosion, while within the irradiated region of the specimen, injected ions are adding material, and if void swelling is occurring, it is creating empty space. An iterative mathematical treatment of SRIM outputs to produce corrected dose and injected ion profiles based on these phenomenon and without regard to diffusion is presented along with examples of differences between SRIM-calculated values and corrected values over a range of typical ion energies. The intent is to provide the reader with a convenient tool for more accurately calculating dose and injected ion profiles for heavy-ion irradiations.

  20. Modification of SRIM-calculated dose and injected ion profiles due to sputtering, injected ion buildup and void swelling

    Science.gov (United States)

    Wang, Jing; Toloczko, Mychailo B.; Bailey, Nathan; Garner, Frank A.; Gigax, Jonathan; Shao, Lin

    2016-11-01

    In radiation effects on materials utilizing self-ion irradiations, it is necessary to calculate the local displacement damage level and ion injection profile because of the short distance that self-ions travel in a material and because of the strong variation of displacement rate with depth in a specimen. The most frequently used tool for this is the software package called Stopping and Range of Ions in Matter (SRIM). A SRIM-calculated depth-dependent dose level is usually determined under the implicit assumption that the target does not undergo any significant changes in volume during the process, in particular SRIM ignores the effect of sputtering, injected ions, and void swelling on the redistribution of the dose and injected ion profiles. This approach become increasingly invalid as the ion fluence reaches ever higher levels, especially for low energy ion irradiations. The original surface is not maintained due to sputter-induced erosion, while within the irradiated region of the specimen, injected ions are adding material, and if void swelling is occurring, it is creating empty space. An iterative mathematical treatment of SRIM outputs to produce corrected dose and injected ion profiles based on these phenomenon and without regard to diffusion is presented along with examples of differences between SRIM-calculated values and corrected values over a range of typical ion energies. The intent is to provide the reader with a convenient tool for more accurately calculating dose and injected ion profiles for heavy-ion irradiations.

  1. Report on fundamental modeling of irradiation-induced swelling and creep in FeCrAl alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kohnert, Aaron A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dasgupta, Dwaipayan [Univ. of Tennessee, Knoxville, TN (United States); Wirth, Brian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Linton, Kory D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-23

    In order to improve the accident tolerance of light water reactor (LWR) fuel, alternative cladding materials have been proposed to replace zirconium (Zr)-based alloys. Of these materials, there is a particular focus on iron-chromium-aluminum (FeCrAl) alloys due to much slower oxidation kinetics in high-temperature steam than Zr-alloys. This should decrease the energy release due to oxidation and allow the cladding to remain integral longer in the presence of high temperature steam, making accident mitigation more likely. As a continuation of the development for these alloys, the material response must be demonstrated to provide suitable radiation stability, in order to ensure that there will not be significant dimensional changes (e.g., swelling), as well as quantifying the radiation hardening and radiation creep behavior. In this report, we describe the use of cluster dynamics modeling to evaluate the defect physics and damage accumulation behavior of FeCrAl alloys subjected to neutron irradiation, with a particular focus on irradiation-induced swelling and defect fluxes to dislocations that are required to model irradiation creep behavior.

  2. Clinical cytology of companion animals: Part II . Cytology of subcutaneous swellings, skin tumours and skin lesions

    NARCIS (Netherlands)

    Teske, E.

    2009-01-01

    Clinical Cytology of Companion Animals: Part 2. Clinical Cytology of Companion Animals: Part 2. Cytology of subcutaneous swellings, skin tumours and skin lesions Subcutaneous swellings, skin tumours, and skin lesions are extremely well suited for cytological examination via FNAB (Fine needle

  3. Evolution of swelling pressure of cohesive-frictional, rough and elasto-plastic granulates

    NARCIS (Netherlands)

    Luding, Stefan; Bauer, Erich; Jiang, Mingjing; Liu, Fang; Bolton, Malcolm

    2010-01-01

    The subject of this study is the modeling of the evolution of the swell-ing pressure of granulates with cohesive-frictional, rough and elasto-plastic “mi-croscopic” contact properties. The spherical particles are randomly arranged in a periodic cubic space with a fixed volume so that an increase of

  4. Swelling behaviour of isora/natural rubber composites in oils used in ...

    Indian Academy of Sciences (India)

    The solvent swelling characteristics of natural rubber composites containing both untreated and alkali treated fibres were investigated in aromatic and aliphatic solvents like toluene, and -hexane. The diffusion experiments were conducted by the sorption gravimetric method. The restrictions on elastomer swelling exerted ...

  5. Loss of knee-extension strength is related to knee swelling after total knee arthroplasty

    DEFF Research Database (Denmark)

    Holm, Bente; Kristensen, Morten T; Bencke, Jesper

    2010-01-01

    To examine whether changes in knee-extension strength and functional performance are related to knee swelling after total knee arthroplasty (TKA).......To examine whether changes in knee-extension strength and functional performance are related to knee swelling after total knee arthroplasty (TKA)....

  6. Polymerization of alanine in the presence of a non-swelling montmorillonite

    Science.gov (United States)

    Paecht-Horowitz, M.; Lahav, N.

    1977-01-01

    Alanine, starting from alanine-adenylate, has been polymerized in the presence of non-swelling Al-montmorillonite. The yield of polymerization is much lower than that obtained in the presence of swelling Na-montmorillonite. The possibility that the changing interlayer spacing in Na-montmorillonite might be responsible for its catalytic properties, is discussed.

  7. Cystic fibrosis transmembrane conductance regulator is involved in polyphenol-induced swelling of the endothelial glycocalyx.

    Science.gov (United States)

    Peters, Wladimir; Kusche-Vihrog, Kristina; Oberleithner, Hans; Schillers, Hermann

    2015-08-01

    Previous studies show that polyphenol-rich compounds can induce a swelling of the endothelial glycocalyx (eGC). Our goal was to reveal the mechanism behind the eGC-swelling. As polyphenols are potent modulators of fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel, the hypothesis was tested whether polyphenol-induced increase in CFTR activity is responsible for the eGC-swelling. The impact of the polyphenols resveratrol, (-)-epicatechin, and quercetin on nanomechanics of living endothelial GM7373 cells was monitored by AFM-nanoindentation. The tested polyphenols lead to eGC-swelling with a simultaneous decrease in cortical stiffness. EGC-swelling, but not the change in cortical stiffness, was prevented by the inhibition of CFTR. Polyphenol-induced eGC-swelling could be mimicked by cytochalasin D, an actin-depolymerizing agent. Thus, in the vascular endothelium, polyphenols induce eGC-swelling by softening cortical actin and activating CFTR. Our findings imply that CFTR plays an important role in the maintenance of vascular homeostasis and may explain the vasoprotective properties of polyphenols. Many vascular problems clinically can be attributed to a dysregulation of endothelial glycocalyx (eGC). The underlying mechanism however remains unclear. In this article, the authors used nanoindentation and showed that polyphenols could swell the endothelial glycocalyx and alter its function. This investigative method can lead to further mechanistic studies of other molecular pathways. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  8. A purple swelling on the tongue | Panta | Pan African Medical Journal

    African Journals Online (AJOL)

    A painless, purple, dome shaped swelling was discovered on routine oral examination in a 20 year old male, near the right lateral border of the tongue. He revealed that the swelling had been growing in a subtle manner since 2 months, and he reported no history of trauma. It measured about 1.5x1.5 cm, surface appeared ...

  9. Swelling of whey and egg white protein hydrogels with stranded and particulate microstructures.

    Science.gov (United States)

    Li, Hui; Zhao, Lei; Chen, Xiao Dong; Mercadé-Prieto, Ruben

    2016-02-01

    Swelling of protein hydrogels in alkaline conditions strongly depends on the gel microstructure. Stranded transparent gels swell as predicted using a modified Flory-Rehner model with the net protein charge. Particulate opaque gels swell very differently, with a sudden increase at a narrow pH range. Its swelling is not controlled by the protein charge, but by the destruction of the non-covalent interactions. Comparable dissolution thresholds, one with pH and another with the degree of swelling, are observed in both types of microstructures. These conclusions are valid for both whey protein isolate (WPI) gels and egg white gels, suggesting that they are universal for all globular proteins that can form such microscructures. Differences are observed, however, from the prevalent chemical crosslinks in each protein system. Non-covalent interactions dominate WPI gels; when such interactions are destroyed at pH≥11.5 the gels swell extensively and eventually dissolve. In egg white gels, the higher degree of disulphide crosslinking allows extensive swelling when non-covalent interactions are destroyed, but dissolution only occurs at pH≥13 when covalent crosslinks are cleaved. The current study highlights that the microstructure of protein hydrogels, a unique particularity of protein systems compared to other synthetic hydrogels, defines swelling. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Swelling/deswelling of polyacrylamide gels in aqueous NaCl solution

    Indian Academy of Sciences (India)

    the osmosis effect ceases and mixing dominates resulting in the exponential swelling of the gel. Further, it can also be seen that DoS depends strongly on the concentration of NaCl. Present observations are consistent with those reported earlier [6,14,15]. To understand the PAAm gels swelling at higher concentrations of ...

  11. Modelling of fission gas swelling in the high burnup UO2 fuel

    International Nuclear Information System (INIS)

    Kim, Dae Ho; Lee, Chan Bock; Bang, Je Gun; Jung, Yeon Ho

    1999-06-01

    Discharge burnup of the fuel in LWR has been increased to improve the fuel economy, and currently the high burnup fuel of over 70 MWd/kg U-rod avg. is being developed by the fuel vendors worldwide. At high burnup, thermal / mechanical properties of the fuel is known to change and new phenomenon could arise. This report describes the model development on fission gas swelling in high burnup UO 2 fuel. For the low burnup fuel, swelling only by the solid fission products has been considered in the fuel performance analysis. However, at high burnup fuel, swelling by fission gas bubbles can not be neglected anymore. Therefore, fission gas swelling model which can predict bubble swelling of the high burnup UO 2 fuel during the steady-state and the transient conditions in LWR was developed. Based on the bubble growth model, the empirical fission gas swelling model was developed as function of burnup, time and temperature. The model showed that fuel bubble swelling would be proportional to the burnup by the power of 1.157 and to the time by the power of 0.157. Comparison of the model prediction with the measured fission gas swelling data under the various burnup and temperature conditions showed that the model would predict the measured data reasonably well. (author). 20 refs., 8 tabs., 17 figs

  12. A rare cause of calf swelling: the Morel-Lavallee lesion.

    LENUS (Irish Health Repository)

    Moriarty, J M

    2011-03-01

    Calf swelling is a common clinical presentation with a wide and varied differential diagnosis. The Morel-Lavallee is a rare cause of subcutaneous swelling, caused by post-traumatic shearing of the hypodermis from the underlying fascia. The potential space so created fills with blood, lymph and necrotic fat giving specific findings on MR evaluation.

  13. Swelling characterization and drug delivery kinetics of polyacrylamide-co-itaconic acid/chitosan hydrogels

    Directory of Open Access Journals (Sweden)

    2009-01-01

    Full Text Available Hybrid polymeric networks composed of polyacrylamide and chitosan were developed to determine their swelling and ascorbic acid delivery kinetics at various chitosan concentrations. The hybrid acrylamide/chitosan hydrogels were synthesized in aqueous itaconic acid solution (1% w/w. Young’s modulus was also evaluated for the hydrogels, and the results were correlated with the swelling properties. Swelling experiments were carried out using three different pH solutions: acidic (pH 4 buffer solution, neutral (distilled water and basic (pH 10 buffer solution. The results of the swelling study showed that the swelling properties of the network varied with the changes of the pH in the swelling solution, as well as concentration of chitosan. When chitosan concentration increased, the swelling capacity diminished, and therefore Young’s modulus increased. The results indicated that the swelling process followed a second order kinetics. The ascorbic acid diffusion inside the hydrogel follows a Fickian mechanism. The ascorbic acid diffusion coefficients are reported as a function of chitosan concentration.

  14. Relationship between phase development and swelling of AISI 316 during temperature changes

    International Nuclear Information System (INIS)

    Yang, W.J.S.; Garner, F.A.

    1982-04-01

    The effect of temperature changes on radiation-induced swelling and phase development of AISI 316 has been examined for specimens irradiated in two different experiments. The formation of radiation-stable phases at low temperature appears to precede swelling but these phases tend to dissolve when subsequently subjected to higher temperature. Phases which develop at high temperature persist when the temperature is subsequently lowered. Once nucleated at low temperatures, voids tend to persist without reduction in density at higher temperatures. However, a new round of void nucleation occurs when the temperature is decreased during irradiation. If the swelling has entered the steady-state swelling regime prior to the temperature change, there is no effect on the subsequent swelling rate. For temperature changes that occur before the end of the transient swelling regime, substantial changes can occur in the swelling behavior, particularly if the changes occur in the range around 500 0 . The isothermal swelling behavior of AISI 316 is much less sensitive to irradiation temperature than previously envisioned

  15. Experimental Analysis on Shrinkage and Swelling in Ordinary Concrete

    Directory of Open Access Journals (Sweden)

    Barbara Kucharczyková

    2017-01-01

    Full Text Available The paper deals with the experimental determination of shrinkage development during concrete ageing. Three concrete mixtures were made. They differed in the amount of cement in the fresh mixture, 300, 350, and 400 kg/m3. In order to determine the influence of plasticiser on the progress of volume changes, another three concrete mixtures were prepared with plasticiser in the amount of 0.25% by cement mass. Measurements were performed with the goal of observing the influence of cement and plasticiser content on the overall development of volume changes in the concrete. Changes in length and mass losses of the concrete during ageing were measured simultaneously. The continuous measurement of concrete mass losses caused by drying of the specimen’s surface proved useful during the interpretation of results obtained from the concrete shrinkage measurement. During the first 24 hours of ageing, all the concrete mixtures exhibited swelling. Its magnitude and progress were influenced by cement, water, and plasticiser content. However, a loss of mass caused by water evaporation from the surface of the specimens was also recorded in this stage. The measured progress of shrinkage corresponded well to the progress of mass loss.

  16. Simulation of PVT and swelling experimental data: a systematic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Paulo S.M.V. [PETROBRAS S.A., Salvador, BA (Brazil). Unidade de Negocios da Bahia]. E-mail: psrocha@petrobras.com.br; Alves, Danilo C.R.; Sacramento, Vinicio S.; Costa, Gloria M.N. [Universidade Salvador (UNIFACS), Salvador, BA (Brazil). Centro de Estudos em Petroleo e Gas Natural (CEPGN)]. E-mail: gloria.costa@unifacs.br

    2004-07-01

    Accurate data of the phase behavior of oil and gas mixtures are needed, for example, for the design of process plants and reservoir simulation studies. Often, experimental PVT data are available, but in practice a few PVT measurements are carried out for a given mixture. Therefore, it is necessary to use a thermodynamic model when planning production strategies for a given petroleum reservoir. This raises the question of what accuracy can be obtained using a cubic equation of state for phase equilibrium calculations, for example at conditions in which oil and gas are being produced. The only way to improve the agreement between measured and calculated results is to adjust the equation of state parameters. Currently, there is not a clear methodology to make these modifications. The objective of this study is to investigate the best tuning to describe the PVT experimental data: differential liberation, constant composition expansion and swelling test. The following programs were used: SPECS and MI-PVT (Technical University of Denmark) and WinProp (windows version of CMGPROP). The Soave-Redlich-Kwong equation of sate was also used. Experimental data for 06 oil samples from Reconcavo Basin (Bahia- Brazil) were obtained in the CEPGN (Study Center on Oil and Natural Gas at UNIFACS) and used in the tuning (author)

  17. Internal structure and swelling behaviour of in silico microgel particles

    Science.gov (United States)

    Rovigatti, Lorenzo; Gnan, Nicoletta; Zaccarelli, Emanuela

    2018-01-01

    Microgels are soft colloids that, by virtue of their polymeric nature, can react to external stimuli such as temperature or pH by changing their size. The resulting swelling/deswelling transition can be exploited in fundamental research as well as for many diverse practical applications, ranging from art restoration to medicine. Such an extraordinary versatility stems from the complex internal structure of the individual microgels, each of which is a crosslinked polymer network. Here we employ a recently-introduced computational method to generate realistic microgel configurations and look at their structural properties, both in real and Fourier space, for several temperatures across the volume phase transition as a function of the crosslinker concentration and of the confining radius employed during the ‘in-silico’ synthesis. We find that the chain-length distribution of the resulting networks can be analytically predicted by a simple theoretical argument. In addition, we find that our results are well-fitted to the fuzzy-sphere model, which correctly reproduces the density profile of the microgels under study.

  18. Mechanical and swelling behaviour of well characterized polybutadiene networks

    Science.gov (United States)

    Mckenna, Gregory B.; Hinkley, Jeffrey A.

    1986-01-01

    Endlinking of hydroxyl-terminated polybutadiene with the appropriate isocyanate has been used to prepare well characterized networks. Two networks have been studied with molecular weights of the prepolymers being 6100 and 2400 g/mole by g.p.c. Cylindrical specimens were prepared and the derivatives of the stored energy function with respect to the stretch invariants were determined by torque and normal force measurements in torsion. From these data the Valanis-Landel (1967) stored energy function derivatives w-prime(lambda) were determined for both networks. The stored energy function for the junction constraint model of Flory (1953, 1977, 1979, 1985) which is a special form of the Valanis-Landel function, has been fitted to that determined from the experiments. The contributions to the stored energy function from the phantom network and from the junction constraints respectively do not agree with predictions from the topologies of the networks. In spite of this, the form of w-prime(lambda) for the junction constraint model gives an excellent 'curve fit' to the data. Comparison is also made with equilibrium swelling.

  19. Nanoscale Swelling Heterogeneities in Type I Collagen Fibrils.

    Science.gov (United States)

    Spitzner, Eike-Christian; Röper, Stephanie; Zerson, Mario; Bernstein, Anke; Magerle, Robert

    2015-06-23

    The distribution of water within the supramolecular structure of collagen fibrils is important for understanding their mechanical properties as well as the biomineralization processes in collagen-based tissues. We study the influence of water on the shape and the mechanical properties of reconstituted fibrils of type I collagen on the nanometer scale. Fibrils adsorbed on a silicon substrate were imaged with multiset point intermittent contact (MUSIC)-mode atomic force microscopy (AFM) in air at 28% relative humidity (RH) and in a hydrated state at 78% RH. Our data reveal the differences in the water uptake between the gap and overlap regions during swelling. This provides direct evidence for different amounts of bound and free water within the gap and overlap regions. In the dry state, the characteristic D-band pattern visible in AFM images is due to height corrugations along a fibril's axis. In the hydrated state, the fibril's surface is smooth and the D-band pattern reflects the different mechanical properties of the gap and overlap regions.

  20. Brain Cell Swelling During Hypocapnia Increases with Hyperglycemia or Ketosis

    Science.gov (United States)

    Glaser, Nicole; Bundros, Angeliki; Anderson, Steve; Tancredi, Daniel; Lo, Weei; Orgain, Myra; O'Donnell, Martha

    2014-01-01

    Severe hypocapnia increases the risk of DKA-related cerebral injury in children, but the reason for this association is unclear. To determine whether the effects of hypocapnia on the brain are altered during hyperglycemia or ketosis, we induced hypocapnia (pCO2 20 ± 3 mmHg) via mechanical ventilation in three groups of juvenile rats: 25 controls, 22 hyperglycemic rats (serum glucose 451± 78 mg/dL) and 15 ketotic rats (beta-hydroxy butyrate 3.0 ± 1.0 mmol/L). We used magnetic resonance imaging to measure cerebral blood flow (CBF) and apparent diffusion coefficient (ADC) values in these groups and in 17 ventilated rats with normal pCO2 (40±3 mmHg). In a subset (n=35), after 2 hrs of hypocapnia, pCO2 levels were normalized (40±3 mmHg) and ADC and CBF measurements repeated. Declines in CBF with hypocapnia occurred in all groups. Normalization of pCO2 after hypocapnia resulted in striatal hyperemia. These effects were not substantially altered by hyperglycemia or ketosis, however, declines in ADC during hypocapnia were greater during both hyperglycemia and ketosis. We conclude that brain cell swelling associated with hypocapnia is increased by both hyperglycemia and ketosis, suggesting that these metabolic conditions may make the brain more vulnerable to injury during hypocapnia. PMID:24443981

  1. A rare presentation of lower back swelling as tailgut cyst

    Directory of Open Access Journals (Sweden)

    Prem Chand

    2016-01-01

    Full Text Available Retrorectal cystic hamartoma, also known as tailgut cyst, is a rare congenital developmental lesion arising from postnatal primitive gut remnants in the retrorectal space. The rarity of the lesion and its anatomical position usually leads to difficulty in diagnosis and surgical management. This cyst predominantly occurs in women (female to male ratio, 3:1. Tailgut cysts can present as incidental findings during the routine examination but over half of the patients are thought to present with symptoms. Computed tomography or magnetic resonance imaging has a crucial role in diagnosing these misdiagnosed cysts. Complete surgical excision is the treatment of choice for tailgut cysts as this provides a definitive diagnosis, relieves symptoms, and prevents possible complications such as infection, fistula formation, and malignant degeneration. We present a case of a 40-year-old female, who presented to us with lower back swelling (7 cm × 5 cm for last 2 years, which had become more prominent to her while sitting. The patient was investigated. Ultrasonography demonstrated ill-defined large cystic lesion (8 cm × 7 cm, posterior to the uterus. Fine needle aspiration cytology suggested sebaceous cyst. A lumbosacral contrast-enhanced computed tomography demonstrated well-defined fluid density mass/collection with enhancing walls in the retrorectal, presacral, precoccygeal area, and suggested tailgut duplication cyst/retrorectal cystic hamartoma. Surgical complete excision of the cystic mass was done with both anterior (transabdominal and posterior approach. Histopathology confirmed a tailgut cyst.

  2. Optical scatter imaging of cellular and mitochondrial swelling in brain tissue models of stroke

    Science.gov (United States)

    Johnson, Lee James

    2001-08-01

    The severity of brain edema resulting from a stroke can determine a patient's survival and the extent of their recovery. Cellular swelling is the microscopic source of a significant part of brain edema. Mitochondrial swelling also appears to be a determining event in the death or survival of the cells that are injured during a stroke. Therapies for reducing brain edema are not effective in many cases and current treatments of stroke do not address mitochondrial swelling at all. This dissertation is motivated by the lack of a complete understanding of cellular swelling resulting from stroke and the lack of a good method to begin to study mitochondrial swelling resulting from stroke in living brain tissue. In this dissertation, a novel method of detecting mitochondrial and cellular swelling in living hippocampal slices is developed and validated. The system is used to obtain spatial and temporal information about cellular and mitochondrial swelling resulting from various models of stroke. The effect of changes in water content on light scatter and absorption are examined in two models of brain edema. The results of this study demonstrate that optical techniques can be used to detect changes in water content. Mie scatter theory, the theoretical basis of the dual- angle scatter ratio imaging system, is presented. Computer simulations based on Mie scatter theory are used to determine the optimal angles for imaging. A detailed account of the early systems is presented to explain the motivations for the system design, especially polarization, wavelength and light path. Mitochondrial sized latex particles are used to determine the system response to changes in scattering particle size and concentration. The dual-angle scatter ratio imaging system is used to distinguish between osmotic and excitotoxic models of stroke injury. Such distinction cannot be achieved using the current techniques to study cellular swelling in hippocampal slices. The change in the scatter ratio is

  3. The Influence of Temperature on Swelling Characteristics of Compacted Bentonite for Waste Disposal

    Directory of Open Access Journals (Sweden)

    Sharif Moniruzzaman Shirazi

    2010-01-01

    Full Text Available A series of experiment was conducted to find out the temperature effect on swelling characteristics of compacted bentonite. The expansion of partly saturated bentonite affects the volume change of air in the specimen respect to initial dry density. Swelling pressure reaches nearly maximum when degree of saturation of specimen is about 95% for all initial dry densities (1.29 ~ 1.95 g/cm3 in swelling pressure test using temperature 20 ~80°C. Initial dry density and temperature are the governing parameter to control the swelling pressure and deformation of compacted bentonite. To predict the swelling pressure an equation has been proposed in relation to content of montmorillonite, temperature and initial dry density of bentonite. The maximum difference between the experimental values and the fitting of this equation is 15% on an average.

  4. Cell swelling activates separate taurine and chloride channels in Ehrlich mouse ascites tumor cells

    DEFF Research Database (Denmark)

    Lambert, Ian Henry; Hoffmann, Else Kay

    1994-01-01

    The taurine efflux from Ehrlich ascites tumor cells is stimulated by hypotonic cell swelling. The swelling-activated taurine efflux is unaffected by substitution of gluconate for extracellular Cl– but inhibited by addition of MK196 (anion channel blocker) and 4,4 -diisothiocyanostilbene-2......,2 -disulfonic acid (DIDS; anion channel and anion exchange blocker) and by depolarization of the cell membrane. This is taken to indicate that taurine does not leave the osmotically swollen Ehrlich cells in exchange for extracellular Cl–, i.e., via the anion exchanger but via a MK196- and DIDS-sensitive channel...... that is potential dependent. An additional stimulation of the swelling-activated taurine efflux is seen after addition of arachidonic acid and oleic acid. Cell swelling also activates a Mini Cl– channel. The Cl– efflux via this Cl– channel, in contrast to the swelling-activated taurine efflux, is unaffected by DIDS...

  5. Relation between the swelling and the disordering in ionic crystals irradiated by fast heavy ions

    International Nuclear Information System (INIS)

    Boccanfuso, M.

    2001-12-01

    When fast heavy ions penetrate in matter, they slow down essentially by depositing their energy on the electrons. This can lead to strong electronic excitation densities in the solid and then to structural modifications. In this work, calcium fluoride (CaF 2 ) was used to look further into the damage induced by irradiation with fast heavy ions in ionic crystals. Four techniques were mainly employed to characterise this damage. These techniques of analysis are wide angle X-ray diffraction, surface profilometry, Rutherford backscattering spectrometry and UV-visible optical absorption spectroscopy. The results of this work show that CaF 2 answers in a multiple way to the electronic excitations. For stopping powers higher than approximately 5 keV/nm, a polygonization seems to occur. This causes a structural disorder, a swelling of 0.27 % and the formation of fractures in the material. A second damage mechanism is caused above approximately 13 keV/nm and results in a loss of the initial crystalline structure. However, optical centres appear whatever the ion stopping power, which indicates that these defects cannot be the cause of the two above mentioned damage mechanisms. According to a thermal spike model, the two thresholds can be linked to melting and sublimation energy of the material, respectively. (author)

  6. Assessment of void swelling in austenitic stainless steel PWR core internals.

    Energy Technology Data Exchange (ETDEWEB)

    Chung, H. M.; Energy Technology

    2006-01-31

    As many pressurized water reactors (PWRs) age and life extension of the aged plants is considered, void swelling behavior of austenitic stainless steel (SS) core internals has become the subject of increasing attention. In this report, the available database on void swelling and density change of austenitic SSs was critically reviewed. Irradiation conditions, test procedures, and microstructural characteristics were carefully examined, and key factors that are important to determine the relevance of the database to PWR conditions were evaluated. Most swelling data were obtained from steels irradiated in fast breeder reactors at temperatures >385 C and at dose rates that are orders of magnitude higher than PWR dose rates. Even for a given irradiation temperature and given steel, the integral effects of dose and dose rate on void swelling should not be separated. It is incorrect to extrapolate swelling data on the basis of 'progressive compounded multiplication' of separate effects of factors such as dose, dose rate, temperature, steel composition, and fabrication procedure. Therefore, the fast reactor data should not be extrapolated to determine credible void swelling behavior for PWR end-of-life (EOL) or life-extension conditions. Although the void swelling data extracted from fast reactor studies is extensive and conclusive, only limited amounts of swelling data and information have been obtained on microstructural characteristics from discharged PWR internals or steels irradiated at temperatures and at dose rates comparable to those of a PWR. Based on this relatively small amount of information, swelling in thin-walled tubes and baffle bolts in a PWR is not considered a concern. As additional data and relevant research becomes available, the newer results should be integrated with existing data, and the worthiness of this conclusion should continue to be scrutinized. PWR baffle reentrant corners are the most likely location to experience high swelling

  7. Assessment of void swelling in austenitic stainless steel PWR core internals

    International Nuclear Information System (INIS)

    Chung, H.M.

    2006-01-01

    As many pressurized water reactors (PWRs) age and life extension of the aged plants is considered, void swelling behavior of austenitic stainless steel (SS) core internals has become the subject of increasing attention. In this report, the available database on void swelling and density change of austenitic SSs was critically reviewed. Irradiation conditions, test procedures, and microstructural characteristics were carefully examined, and key factors that are important to determine the relevance of the database to PWR conditions were evaluated. Most swelling data were obtained from steels irradiated in fast breeder reactors at temperatures >385 C and at dose rates that are orders of magnitude higher than PWR dose rates. Even for a given irradiation temperature and given steel, the integral effects of dose and dose rate on void swelling should not be separated. It is incorrect to extrapolate swelling data on the basis of 'progressive compounded multiplication' of separate effects of factors such as dose, dose rate, temperature, steel composition, and fabrication procedure. Therefore, the fast reactor data should not be extrapolated to determine credible void swelling behavior for PWR end-of-life (EOL) or life-extension conditions. Although the void swelling data extracted from fast reactor studies is extensive and conclusive, only limited amounts of swelling data and information have been obtained on microstructural characteristics from discharged PWR internals or steels irradiated at temperatures and at dose rates comparable to those of a PWR. Based on this relatively small amount of information, swelling in thin-walled tubes and baffle bolts in a PWR is not considered a concern. As additional data and relevant research becomes available, the newer results should be integrated with existing data, and the worthiness of this conclusion should continue to be scrutinized. PWR baffle reentrant corners are the most likely location to experience high swelling rates, and

  8. Generation of continental rifts, basins, and swells by lithosphere instabilities

    Science.gov (United States)

    Fourel, Loïc.; Milelli, Laura; Jaupart, Claude; Limare, Angela

    2013-06-01

    Continents may be affected simultaneously by rifting, uplift, volcanic activity, and basin formation in several different locations, suggesting a common driving mechanism that is intrinsic to continents. We describe a new type of convective instability at the base of the lithosphere that leads to a remarkable spatial pattern at the scale of an entire continent. We carried out fluid mechanics laboratory experiments on buoyant blocks of finite size that became unstable due to cooling from above. Dynamical behavior depends on three dimensionless numbers, a Rayleigh number for the unstable block, a buoyancy number that scales the intrinsic density contrast to the thermal one, and the aspect ratio of the block. Within the block, instability develops in two different ways in an outer annulus and in an interior region. In the outer annulus, upwellings and downwellings take the form of periodically spaced radial spokes. The interior region hosts the more familiar convective pattern of polygonal cells. In geological conditions, such instabilities should manifest themselves as linear rifts striking at a right angle to the continent-ocean boundary and an array of domal uplifts, volcanic swells, and basins in the continental interior. Simple scaling laws for the dimensions and spacings of the convective structures are derived. For the subcontinental lithospheric mantle, these dimensions take values in the 500-1000 km range, close to geological examples. The large intrinsic buoyancy of Archean lithospheric roots prevents this type of instability, which explains why the widespread volcanic activity that currently affects Western Africa is confined to post-Archean domains.

  9. Cell swelling and ion redistribution assessed with intrinsic optical signals

    Directory of Open Access Journals (Sweden)

    WITTE OTTO W.

    2001-01-01

    Full Text Available Cell volume changes are associated with alterations of intrinsic optical signals (IOS. In submerged brain slices in vitro, afferent stimulation induces an increase in light transmission. As assessed by measurement of the largely membrane impermeant ion tetramethylammonium (TMA in the extracellular space, these IOS correlate with the extent and time course of the change of the extracellular space size. They have a high signal to noise ratio and allow measurements of IOS changes in the order of a few percent. Under conditions of reduced net KCl uptake (low Cl solution a directed spatial buffer mechanism (K syphoning can be demonstrated in the neocortex with widening of the extracellular space in superficial layers associated with a reduced light transmission and an increase of extracellular K concentration. The nature of the IOS under pathophysiological conditions is less clear. Spreading depressions first cause an increase of light transmission, then a decrease. Such a decrease has also been observed following application of NMDA where it was associated with structural damage. Pharmacological analyses suggest that under physiological conditions changes of extracellular space size are mainly caused by astrocytic volume changes while with strong stimuli and under pathophysiological conditions also neuronal swelling occurs. With reflected light usually signals opposite to those observed with transmitted light are seen. Recording of IOS from interface slices gives very complex signals since under these conditions an increase of light transmission has been reported to be superimposed by a decrease of the signal due to mechanical lensing effects of the slice surface. Depending on the method of measurement and the exact conditions, several mechanisms may contribute to IOS. Under well defined conditions IOS are a useful supplementary tool to monitor changes of extracellular volume both in space and time.

  10. Deformation mechanisms in a coal mine roadway in extremely swelling soft rock.

    Science.gov (United States)

    Li, Qinghai; Shi, Weiping; Yang, Renshu

    2016-01-01

    The problem of roadway support in swelling soft rock was one of the challenging problems during mining. For most geological conditions, combinations of two or more supporting approaches could meet the requirements of most roadways; however, in extremely swelling soft rock, combined approaches even could not control large deformations. The purpose of this work was to probe the roadway deformation mechanisms in extremely swelling soft rock. Based on the main return air-way in a coal mine, deformation monitoring and geomechanical analysis were conducted, as well as plastic zone mechanical model was analysed. Results indicated that this soft rock was potentially very swelling. When the ground stress acted alone, the support strength needed in situ was not too large and combined supporting approaches could meet this requirement; however, when this potential released, the roadway would undergo permanent deformation. When the loose zone reached 3 m within surrounding rock, remote stress p ∞ and supporting stress P presented a linear relationship. Namely, the greater the swelling stress, the more difficult it would be in roadway supporting. So in this extremely swelling soft rock, a better way to control roadway deformation was to control the releasing of surrounding rock's swelling potential.

  11. Swelling kinetics and electrical charge transport in PEDOT:PSS thin films exposed to water vapor.

    Science.gov (United States)

    Sarkar, Biporjoy; Jaiswal, Manu; Satapathy, Dillip K Kumar

    2018-04-16

    We report the swelling kinetics and evolution of the electrical charge transport in poly(3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT:PSS) thin films subjected to water vapor. Polymer films swell by the diffusion of water vapor and are found to undergo structural relaxations. Upon exposure to water vapor, primarily the hygroscopic PSS shell, which surrounds the conducting PEDOT-rich cores, takes up water vapor and subsequently swells. We found that the degree of swelling largely depends on the PEDOT to PSS ratio. Swelling driven microscopic rearrangement of the conducting PEDOT-rich cores in the PSS matrix strongly influences the electrical charge transport of the polymer film. Swelling induced increase as well as decrease of electrical resistance are observed in polymer films having different PEDOT to PSS ratio. This anomalous charge transport behavior in PEDOT:PSS films is reconciled by taking into account the contrasting swelling behavior of the PSS and the conducting PEDOT-rich cores leading to spatial segregation of PSS in films with PSS as a minority phase and by a net increase in mean separation between conducting PEDOT-rich cores for films having abundance of PSS. © 2018 IOP Publishing Ltd.

  12. Fractional cable equation for general geometry: A model of axons with swellings and anomalous diffusion

    Science.gov (United States)

    López-Sánchez, Erick J.; Romero, Juan M.; Yépez-Martínez, Huitzilin

    2017-09-01

    Different experimental studies have reported anomalous diffusion in brain tissues and notably this anomalous diffusion is expressed through fractional derivatives. Axons are important to understand neurodegenerative diseases such as multiple sclerosis, Alzheimer's disease, and Parkinson's disease. Indeed, abnormal accumulation of proteins and organelles in axons is a hallmark of these diseases. The diffusion in the axons can become anomalous as a result of this abnormality. In this case the voltage propagation in axons is affected. Another hallmark of different neurodegenerative diseases is given by discrete swellings along the axon. In order to model the voltage propagation in axons with anomalous diffusion and swellings, in this paper we propose a fractional cable equation for a general geometry. This generalized equation depends on fractional parameters and geometric quantities such as the curvature and torsion of the cable. For a cable with a constant radius we show that the voltage decreases when the fractional effect increases. In cables with swellings we find that when the fractional effect or the swelling radius increases, the voltage decreases. Similar behavior is obtained when the number of swellings and the fractional effect increase. Moreover, we find that when the radius swelling (or the number of swellings) and the fractional effect increase at the same time, the voltage dramatically decreases.

  13. Episodic swell growth inferred from variable uplift of the Cape Verde hotspot islands

    Science.gov (United States)

    Ramalho, R.; Helffrich, G.; Cosca, M.; Vance, D.; Hoffmann, D.; Schmidt, D.N.

    2010-01-01

    On the Beagle voyage, Charles Darwin first noted the creation and subsidence of ocean islands, establishing in geology's infancy that island freeboard changes with time. Hotspot ocean islands have an obvious mechanism for freeboard change through the growth of the bathymetric anomaly, or swell, on which the islands rest. Models for swell development indicate that flexural, thermal or dynamic pressure contributions, as well as spreading of melt residue from the hotspot, can all contribute to island uplift. Here we test various models for swell development using the uplift histories for the islands of the Cape Verde hotspot, derived from isotopic dating of marine terraces and subaerial to submarine lava-flow morphologies. The island uplift histories, in conjunction with inter-island spacing, uplift rate and timing differences, rule out flexural, thermal or dynamic pressure contributions. We also find that uplift cannot be reconciled with models that advocate the spreading of melt residue in swell development unless swell growth is episodic. Instead, we infer from the uplift histories that two processes have acted to raise the islands during the past 6 Myr. During an initial phase, mantle processes acted to build the swell. Subsequently, magmatic intrusions at the island edifice caused 350 m of local uplift at the scale of individual islands. Finally, swell-wide uplift contributed a further 100 m of surface rise.

  14. Simulated swelling during low-temperature N2 adsorption in polymers of intrinsic microporosity.

    Science.gov (United States)

    Hart, Kyle E; Springmeier, Jeffrey M; McKeown, Neil B; Colina, Coray M

    2013-12-14

    Polymers of intrinsic microporosity (PIMs) are a promising alternative in gas separation applications; however, their industrial applicability is greatly reduced by their susceptibility toward sorption-induced plasticization. In this study, the effects of swelling during nitrogen adsorption isotherms at 77 K for five PIMs (PIM-1, PIM-1c, PIM-SBF, PIM-SBF-Me, and sPIM-1) were examined through predictive molecular simulations. The structural changes and adsorptive implications of swelling each PIM from 0 to 15% were analyzed by generating swollen "snapshots" of the PIM during the swelling process by means of an effective swelling procedure. The size of the free volume elements increased with the simulated swelling percentage, while the closely packed polymer chains remained associated. By comparing the simulated swollen and available experimental isotherms, this investigation shows that the amount of swelling observed during low-temperature nitrogen adsorption is strongly correlated with the interaction strength of the polymer matrix. Therefore, this study provides further support that PIMs should be designed with functionalities to increase the associative interactions of adjacent polymer chains while simultaneously prohibiting efficient packing to construct a gas separation membrane with limited low-temperature N2 swelling and high free volumes.

  15. On the Possible Impact of a Following-Swell on the Atmospheric Boundary Layer

    Science.gov (United States)

    Makin, V. K.

    2008-12-01

    A simple model of the atmospheric boundary layer over the ocean where the swell impact on the atmosphere is explicitly accounted for is suggested. The model is based on Ekman’s equations, where the stress in the wave boundary layer is split into two parts: the turbulent and wave-induced stress. The turbulent stress is parameterized traditionally via the eddy viscosity proportional to the generalized mixing length. The wave-induced stress directed upward (from swell to the atmosphere) is parameterized using the formalism of the wind-over-waves coupling theory. The model can be seen as an extension of the model by Kudryavtsev and Makin (J Phys Oceanogr 34:934 949, 2004) to the scale of the entire atmospheric boundary layer by including the Coriolis force into the momentum conservation equation and generalizing the definition of the mixing length. The regime of low winds for swell propagating along the wind direction is studied. It is shown that the impact of swell on the atmosphere is governed mainly by the swell parameter—the coupling parameter that is the product of the swell steepness and the growth rate coefficient. When the coupling parameter drops below - 1 the impact of swell becomes significant and affects the entire atmospheric boundary layer. The turbulent stress is enhanced near the surface as compared to the no-swell case, and becomes negative above the height of the inner region. The wind profile is characterized by a positive gradient near the surface and a negative gradient above the height of the inner region forming a characteristic bump at the height of the inner region. Results of the model agree at least qualitatively with observations performed in the atmosphere in presence of swell.

  16. Characterization of Swelling Clays as Components of the Engineered Barrier System for Geological Repositories. Results of an IAEA Coordinated Research Project 2002-2007

    International Nuclear Information System (INIS)

    2013-11-01

    At the request of the Member States, the IAEA coordinates research into subjects of common interest in the context of the peaceful application of nuclear technology. The coordinated research projects (CRPs) are intended to promote knowledge and technology transfer between Member States and are largely focused on subjects of prime interest to the international nuclear community. This report presents the results of a CRP carried out between 2002 and 2007 on the subject of swelling clays proposed for use as a component in the engineered barrier system (EBS) of the multibarrier concept for disposal of radioactive waste. In 2002, under the auspices of the IAEA, a number of Member States came together to form a Network of Centres of Excellence on Training in and Demonstration of Waste Disposal Technologies in Underground Research Facilities (URF Network). This network identified the general subject of the application of high swelling clays to seal repositories for radioactive waste, with specific emphasis on the isolation of high level radioactive waste from the biosphere, as being suitable for a CRP. Existing concepts for geological repositories for high level radioactive waste and spent nuclear fuel require the use of EBSs to ensure effective isolation of the radioactive waste. There are two major materials proposed for use in the EBS, swelling clay based materials and cementitious/concrete materials. These materials will be placed between the perimeter of the excavation and the waste container to fill the existing gap and ensure isolation of the waste within the canister (also referred to as a container in some EBS concepts) by supporting safety through retardation and confinement. Cementitious materials are industrially manufactured to consistent standards and are readily available in most locations and therefore their evaluation is of less value to Member States than that of swelling clays. There exists a considerable range of programme development regarding

  17. Kimura Disease Manifesting as Synchronous Bilateral Parotid Swelling in a Young Middle-Eastern Patient

    Directory of Open Access Journals (Sweden)

    Fatemah Faras

    2014-01-01

    Full Text Available Kimura disease is a rare, benign, chronic inflammatory swelling of the subcutaneous tissue, lymph nodes, and glandular tissue. Characteristic features of the disease include, but not limited to, painless subcutaneous head and neck swelling, blood and tissue eosinophilia, and markedly elevated immunoglobulin E (IgE levels. Herein, we report a rare case of Kimura disease manifesting as synchronous bilateral parotid swelling of 12 years duration in a 33-year-old Middle-Eastern man. To our knowledge only few cases have been reported in the literature involving bilateral parotid glands, and this is the first case to be reported in the Middle East.

  18. Anesthetic concerns in a huge congenital sublingual swelling obscuring airway access

    Directory of Open Access Journals (Sweden)

    Nilesh Kumar

    2015-01-01

    Full Text Available Presence of intraoral pathology poses a great challenge during management of pediatric airway. We report management of big intraoral cystic swelling physically occupying the entire oral cavity restricting access to airway. Preintubation aspiration of swelling was done to decrease its size and make room for airway manipulation, followed by laryngoscopy and intubation in lateral position. Airway patency is at risk in postoperative period also, in this case, though the swelling decreased in size postoperatively but presence of significant edema required placement of tongue stitch and modified nasopharyngeal airway. Case report highlights simple maneuvers to manage a difficult case.

  19. On grain size dependent void swelling in pure copper irradiated with fission neutrons

    DEFF Research Database (Denmark)

    Singh, B.N.; Eldrup, Morten Mostgaard; Zinkle, S.J.

    2001-01-01

    void swelling measured under irradiation producing only Frenkel pairs could be satisfactorily explained in terms of the standard rate theory (SRT) and dislocation bias. Experimental results reported in the 1980sdemonstrated, on the other hand, that the effect of grain boundaries on void swelling under...... in pure copper irradiated with fission neutrons at 623K to a dose level of approx0.3 dpa (displacement peratom). The post-irradiation defect microstructure including voids was investigated using transmission electron microscopy and positron annihilation spectroscopy. The evolution of void swelling...

  20. Development of a coal shrinkage-swelling model accounting for water content in the micropores

    Energy Technology Data Exchange (ETDEWEB)

    Prob Thararoop; Zuleima T. Karpyn; Turgay Ertekin [Pennsylvania State University, University Park, PA (United States). Petroleum and Natural Gas Engineering

    2009-07-01

    Changes in cleat permeability of coal seams are influenced by internal stress, and release or adsorption of gas in the coal matrix during production/injection processes. Coal shrinkage-swelling models have been proposed to quantify such changes; however none of the existing models incorporates the effect of the presence of water in the micropores on the gas sorption of coalbeds. This paper proposes a model of coal shrinkage and swelling, incorporating the effect of water in the micropores. The proposed model was validated using field permeability data from San Juan basin coalbeds and compared with coal shrinkage and swelling models existing in the literature.

  1. Precipitants of hepatic encephalopathy induce rapid astrocyte swelling in an oxidative stress dependent manner.

    Science.gov (United States)

    Lachmann, Vera; Görg, Boris; Bidmon, Hans Jürgen; Keitel, Verena; Häussinger, Dieter

    2013-08-15

    Hepatic encephalopathy (HE) is seen as the clinical manifestation of a low grade cerebral edema with formation of reactive oxygen and nitrogen species (RNOS). Astrocyte swelling is a crucial event and in cultured astrocytes HE-relevant factors almost instantaneously induce the formation of RNOS. However, short term effects of ammonia, inflammatory cytokines and RNOS on the volume of astrocytes and other brain cells as well as the underlying mechanisms are largely unknown, although a pathogenic link between RNOS formation and swelling in HE has been proposed. This issue was addressed in the present study by means of live-cell volume microscopy of brain cells in vitro. Ammonia, diazepam and pro-inflammatory cytokines such as tumor-necrosis factor-α (TNF-α), interferon-γ, interleukin-1β induced within 20min astrocyte swelling by about 25% accompanied by nuclear swelling of similar magnitude. Astrocyte swelling in response to NH4Cl, TNF-α or diazepam was abolished by the antioxidant epigallocatechin-gallate pointing to an involvement of RNOS. NH4Cl-induced astrocyte swelling was sensitive to inhibition of glutamine synthetase, NADPH oxidase or nitric oxide synthases. In line with a NMDA receptor-, prostanoid- and Ca(2+)-dependence of NH4Cl-induced RNOS formation, Ca(2+) chelation and inhibition of NMDA receptors or cyclooxygenase suppressed NH4Cl-induced astrocyte swelling, whereas the Ca(2+)-ionophore ionomycin, NMDA, glutamate and prostanoids induced rapid astrocyte swelling. NH4Cl also induced swelling of cultured microglia in a glutamine-synthesis dependent way, but had no effect on cell volume of cultured neurons. It is concluded that the pathways which trigger RNOS formation in astrocytes also trigger astrocyte swelling, whereas conversely and as shown previously hypoosmotic astrocyte swelling can induce RNOS formation. This establishes a complex interplay with an auto-amplificatory loop between RNOS formation and astrocyte swelling as an important event in

  2. The Bending Strength, Internal Bonding and Thickness Swelling of a Five Layer Sandwiched Bamboo Particleboard

    Science.gov (United States)

    Jamaludin, M. A.; Bahari, S. A.; Nordin, K.; Soh, T. F. T.

    2010-03-01

    The demand for wood based material is increasing but the supply is decreasing. Therefore the price of these raw materials has increased. Bamboo provides an economically feasible alternative raw material for the wood based industry. Its properties are comparable to wood. It is also compatible with the existing processing technology. Bamboo is in abundance, easy to propagate and of short maturation period. Bamboo provides a cheaper alternative resource for the wood based industry. The development of new structural components from bamboo will widen its area of application from handicrafts to furniture and building components. In this study, five layer sandwiched bamboo particleboard were manufactured. The sandwiched Bamboo PB consists of a bamboo PB core, oil palm middle veneers and thin meranti surface veneers. The physical and mechanical properties of the bamboo sandwiched particleboards were tested in accordance to the BS-EN 317:1993 [1] and BS-EN 310:1993 [2], respectively. All the samples passed the standards. The modulus of elasticity was about 352% higher than the value specified in the BS standard, BS-EN 312-4:1996 [3]. The Internal bonding was about 23% higher than the general requirements specified in the standard. On the other hand, the thickness swelling was about 6% lower than the standard. No glue line failure was observed in the strength tests. Critical failures in the IB tests were observed in the particleboards. Tension failures were observed in the surface veneers in the bending tests. The five layer sandwiched bamboo particleboard can be used for light weight construction such as furniture, and wall and door panels in buildings.

  3. Synergistic effect of helium and hydrogen for bubble swelling in reduced-activation ferritic/martensitic steel under sequential helium and hydrogen irradiation at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Wenhui [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Hubei Nuclear Solid Physics Key Laboratory and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Guo, Liping, E-mail: guolp@whu.edu.cn [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Hubei Nuclear Solid Physics Key Laboratory and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Chen, Jihong; Luo, Fengfeng; Li, Tiecheng [Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Hubei Nuclear Solid Physics Key Laboratory and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Ren, Yaoyao [Center for Electron Microscopy, Wuhan University, Wuhan 430072 (China); Suo, Jinping; Yang, Feng [State Key Laboratory of Mould Technology, Institute of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-04-15

    Highlights: • Helium/hydrogen synergistic effect can increase irradiation swelling of RAFM steel. • Hydrogen can be trapped to the outer surface of helium bubbles. • Too large a helium bubble can become movable. • Point defects would become mobile and annihilate at dislocations at high temperature. • The peak swelling temperature for RAFM steel is 450 °C. - Abstract: In order to investigate the synergistic effect of helium and hydrogen on swelling in reduced-activation ferritic/martensitic (RAFM) steel, specimens were separately irradiated by single He{sup +} beam and sequential He{sup +} and H{sup +} beams at different temperatures from 250 to 650 °C. Transmission electron microscope observation showed that implantation of hydrogen into the specimens pre-irradiated by helium can result in obvious enhancement of bubble size and swelling rate which can be regarded as a consequence of hydrogen being trapped by helium bubbles. But when temperature increased, Ostwald ripening mechanism would become dominant, besides, too large a bubble could become mobile and swallow many tiny bubbles on their way moving, reducing bubble number density. And these effects were most remarkable at 450 °C which was the peak bubble swelling temperature for RAMF steel. When temperature was high enough, say above 450, point defects would become mobile and annihilate at dislocations or surface. As a consequence, helium could no longer effectively diffuse and clustering in materials and bubble formation was suppressed. When temperature was above 500, helium bubbles would become unstable and decompose or migrate out of surface. Finally no bubble was observed at 650 °C.

  4. On the swelling behavior of cationic exchange resins saturated with Na+ ions in a C3S paste

    International Nuclear Information System (INIS)

    Lafond, E.; Cau Dit Coumes, C.; Chartier, D.; Gauffinet, S.; Le Bescop, P.; Stefan, L.

    2015-01-01

    Ion exchange resins (IERs) are widely used in the nuclear industry to decontaminate radioactive effluents. Spent resins are usually encapsulated in cementitious materials. However, the solidified waste form can exhibit strong expansion, possibly leading to cracking, if the appropriate binder is not used. In this work, the interactions between cationic resins in the Na + form and tricalcium silicate are investigated during the early stages of hydration in order to gain a better understanding of the expansion process. It is shown that the IERs exhibit a transient swelling of small magnitude due to the decrease in the osmotic pressure of the external solution. This expansion, which occurs just after setting, is sufficient to damage the material which is poorly consolidated for several reasons: low degree of hydration, precipitation of poorly cohesive sodium-bearing C-S-H, and very heterogeneous microstructure with zones of high porosity. (authors)

  5. Investigation of He-induced swelling behaviour of inert matrices by 10B: the Bodex irradiation experiment

    International Nuclear Information System (INIS)

    Den Exter, M.; Klaassen, F.; Haas, G.J. de

    2007-01-01

    The BODEX experiment, part of the FP6 integrated project EUROTRANS, assesses the behaviour of inert matrices, envisaged for americium transmutation; magnesium oxide, yttrium-stabilised zirconium dioxide and 95 Mo-depleted molybdenum. More specific: the swelling behaviour due to He formation will be studied and compared for each matrix material. The work comprises the fabrication of the targets, doped with 10 B for fast He production and doped with 11 B as reference material, and subsequent irradiation and post-irradiation Examination (PIE) in the High Flux Reactor in Petten, The Netherlands. Though the work is still in progress, some preliminary results of the target production are presented together with the irradiation proposal. (authors)

  6. Void Swelling and Microstructure of Austenitic Stainless Steels Irradiated in the BOR - 60 Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y. [Argonne National Lab. (ANL), Argonne, IL (United States); Yang, Yong [Argonne National Lab. (ANL), Argonne, IL (United States); Huang, Yina [Argonne National Lab. (ANL), Argonne, IL (United States); Allen, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Alexandreanu, B. [Argonne National Lab. (ANL), Argonne, IL (United States); Natesan, K. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2012-11-01

    As nuclear power plants age and neutron fluence increases, detrimental effects resulting from radiation damage have become an increasingly important issue for the operational safety and structural integrity of core internal components. In this study, irradiated specimens of reactor core internal components were characterized by transmission electron microscopy. The specimens had been irradiated to 5.5-45 dpa in the BOR-60 reactor at a dose rate close to 10-6 dpa/s and temperature of about 320°C. No voids were observed in the austenitic stainless steels and nickel alloys at all doses. Despite the possibility that fine voids below the TEM resolution limit may be present, it was clear that void swelling was insignificant in all examined alloys up to 45 dpa. Irradiated microstructures of the studied alloys were dominated by a high density of Frank loops. The mean size and density of the Frank loops varied from one material to another, but saturated with increasing dose above ~10 dpa. While no irradiation-induced precipitations were present below 24.5 dpa, fine precipitates were evident in several alloys at 45 dpa.

  7. Effects of impurity trapping on irradiation-induced swelling and creep

    Energy Technology Data Exchange (ETDEWEB)

    Mansur, L. K.; Yoo, M. H.

    1977-12-01

    A general theory of the effects of point defect trapping on radiation-induced swelling and creep deformation rates is developed. The effects on the fraction of defects recombining, and on void nucleation, void growth and creep due to the separate processes of dislocation climb-glide and dislocation climb (the so-called SIPA mechanism) are studied. Trapping of vacancies or interstitials increases total recombination and decreases the rates of deformation processes. For fixed trapping parameters, the reduction is largest for void nucleation, less for void growth and creep due to dislocation climb-glide, and least for creep due to dislocation climb. With this formation, the effects of trapping at multiple vacancy and interstitial traps and of spatial and temporal variation in trap concentrations may be determined. Alternative pictures for viewing point defect trapping in terms of effective recombination and diffusion coefficients are derived. It is shown that previous derivations of these coefficients are incorrect. A rigorous explanation is given of the well-known numerical result that interstitial trapping is significant only if the binding energy exceeds the difference between the vacancy and interstitial migration energies, while vacancy trapping is significant even at small binding energies. Corrections which become necessary at solute concentrations above about 0.1% are described. Numerical results for a wide range of material and irradiation parameters are presented.

  8. FINE NEEDLE ASPIRATION CYTOLOGY OF EPIDIDYMAL SWELLINGS IN RIMS HOSPITAL, IMPHAL: A FIVE-YEAR STUDY

    Directory of Open Access Journals (Sweden)

    Rajesh Singh Laishram

    2016-06-01

    Full Text Available BACKGROUND Epididymal nodules are frequently encountered in surgical practice. They are easily accessible to fine needle aspiration cytology (FNAC. Clinically, these nodules present as worrisome nodules to the patients as well to the patients. This study was conducted to study the clinico-pathological profile of patients presenting with epididymal nodule using fine needle aspiration cytology (FNAC. METHODS A retrospective study was done by critically analysing the FNAC reports of palpable epididymal swellings in last five years (January 2010 to December 2015 at the Department of Pathology, Regional Institute of Medical Sciences (RIMS Hospital, Imphal, Manipur. Review of all the reports were done and diagnosis was made according to standard guidelines and correlated with patient’s age, sex, and side of involvement to explore the disease pattern. RESULTS A total of 71 cases were retrieved and divided as follows: Tuberculous epididymitis 20(28.17%, spermatocoele 11(15.49%, non-specific chronic epididymitis 10(14.08%, spermatic granulomas 6(8.45%, acute epididymitis 6(8.45%, hydrocoele 5 (7.04%, adenomatoid tumour 4(6.63% and microfilaria 1(1.41%. FNAC material was inadequate for opinion in 8 cases (11.28% cases. CONCLUSION FNAC has a definite important role in the differential diagnosis of epididymal nodules as it can identify neoplastic and nonneoplastic conditions. FNAC can thus be used to segregate the group of patients requiring a surgical intervention and a biopsy

  9. A one-dimensional mixed porohyperelastic transport swelling finite element model with growth

    Science.gov (United States)

    Harper, J.L.; Simon, B.R.; Vande Geest, J.P.

    2013-01-01

    A one-dimensional, large-strain, mixed porohyperelastic transport and swelling (MPHETS) finite element model was developed in MATLAB and incorporated with a well-known growth model for soft tissues to allow the model to grow (increase in length) or shrink (decrease in length) at constant material density. By using the finite element model to determine the deformation and stress state, it is possible to implement different growth laws in the program in the future to simulate how soft tissues grow and behave when exposed to various stimuli (e.g. mechanical, chemical, or electrical). The essential assumptions needed to use the MPHETS model with growth are clearly identified and explained in this paper. The primary assumption in this work, however, is that the stress upon which growth acts is the stress in the solid skeleton, i.e. the effective stress, Seff. It is shown that significantly different amounts of growth are experienced for the same loading conditions when using a porohyperelastic model as compared to a purely solid model. In one particular example, approximately 51% less total growth occurred in the MPHETS model than in the solid model even though both problems were subjected to the same external loading. This work represents a first step in developing more sophisticated models capable of capturing the complex mechanical and biochemical environment in growing and remodeling tissues. PMID:23778062

  10. Tumescent anesthesia for reducing pain, swelling, and ecchymosis during polycaprolactone filler injections in the face.

    Science.gov (United States)

    Kim, JongSeo

    2017-11-01

    PCL filler can be injected in two major ways to control pain. One such method involves mixing 0.3cc of PCL filler with lidocaine, and the other is the method introduced in this report, which involves pre-injection with a tumescent solution. It is hard to reduce pain effectively with pre-mixing PCL filler with lidocaine because there may be not enough time to act lidocaine solution effect immediately for pain control. The pre-mixing method changes the properties of the original filler, especially the property of the CMC portion. Therefore, in my simple and novel technique, tumescent solution is injected, followed by PCL filler which preserves the original CMC property. This is done after sedation of the tissue by the tumescent solution and dissection of soft tissue to create a space for the ensuing PCL injection. After pre-injection with tumescent solution, histological analysis indicated that the tissue did not become irritated in response to the foreign body material (PCL filler) or the mechanical trauma caused by the needle. That is the key mechanism of the tumescent injection method for reducing tissue reaction and that may reduce pain and swelling during and after PCL filler injections.

  11. Energy Recovery from Solutions with Different Salinities Based on Swelling and Shrinking of Hydrogels

    KAUST Repository

    Zhu, Xiuping

    2014-06-17

    Several technologies, including pressure-retarded osmosis (PRO), reverse electrodialysis (RED), and capacitive mixing (CapMix), are being developed to recover energy from salinity gradients. Here, we present a new approach to capture salinity gradient energy based on the expansion and contraction properties of poly(acrylic acid) hydrogels. These materials swell in fresh water and shrink in salt water, and thus the expansion can be used to capture energy through mechanical processes. In tests with 0.36 g of hydrogel particles 300 to 600 μm in diameter, 124 mJ of energy was recovered in 1 h (salinity ratio of 100, external load of 210 g, water flow rate of 1 mL/min). Although these energy recovery rates were relatively lower than those typically obtained using PRO, RED, or CapMix, the costs of hydrogels are much lower than those of membranes used in PRO and RED. In addition, fouling might be more easily controlled as the particles can be easily removed from the reactor for cleaning. Further development of the technology and testing of a wider range of conditions should lead to improved energy recoveries and performance. © 2014 American Chemical Society.

  12. The Effects of Swelling and Porosity Change on Capillarity: DEM Coupled with a Pore-Unit Assembly Method.

    Science.gov (United States)

    Sweijen, Thomas; Nikooee, Ehsan; Hassanizadeh, S Majid; Chareyre, Bruno

    In this study, a grain-scale modelling technique has been developed to generate the capillary pressure-saturation curves for swelling granular materials. This model employs only basic granular properties such as particles size distribution, porosity, and the amount of absorbed water for swelling materials. Using this model, both drainage and imbibition curves are directly obtained by pore-scale simulations of fluid invasion. This allows us to produce capillary pressure-saturation curves for a large number of different packings of granular materials with varying porosity and/or amount of absorbed water. The algorithm is based on combining the Discrete Element Method for generating different particle packings with a pore-unit assembly approach. The pore space is extracted using a regular triangulation, with the centres of four neighbouring particles forming a tetrahedron. The pore space within each tetrahedron is referred to as a pore unit. Thus, the pore space of a particle packing is represented by an assembly of pore units for which we construct drainage and imbibition capillary pressure-saturation curves. A case study on Hostun sand is conducted to test the model against experimental data from literature and to investigate the required minimum number of particles to have a Representative Elementary Volume. Then, the capillary pressure-saturation curves are constructed for Absorbent Gelling Material particles, for different combinations of porosity values and amounts of absorbed water. Each combination yields a different configuration of pore units, and thus distinctly different capillary pressure-saturation curves. All these curves are shown to collapse into one curve for drainage and one curve for imbibition when we normalize capillary pressure and saturation values. We have developed a formula for the Van Genuchten parameter [Formula: see text] (which is related to the inverse of the entry pressure) as a function of porosity and the amount of absorbed water.

  13. Swelling/deswelling of polyacrylamide gels in aqueous NaCl ...

    Indian Academy of Sciences (India)

    deswelling of polyacrylamide gels in aqueous NaCl solution: Light scattering and macroscopic swelling study. M Sivanantham B V R Tata ... Keywords. Polyacrylamide hydrogel; salt solution; diffusion coefficient; light scattered; inhomogeneities.

  14. Effect of compression therapy on knee swelling and pain after total knee arthroplasty

    DEFF Research Database (Denmark)

    Munk, Stig; Jensen, Niels J F; Andersen, Ida

    2013-01-01

    PURPOSE: Knee swelling after total knee arthroplasty may impair postoperative mobilisation and training, and as medical elastic compression stockings are well tolerated and effective to prevent oedema, haematoma and postoperative pain after venous surgery, we wanted to study whether this effect...... could be transferred to total knee arthroplasty surgery reducing postoperative swelling and pain and thereby facilitating mobilisation and improving patient-reported knee function. METHODS: In a randomised controlled study, 88 patients were randomised to use either a medical elastic compression stocking...... or no stocking from the first postoperative day and the following 4 weeks after total knee arthroplasty. Outcome measures were knee, calf and ankle swelling, knee flexion, pain and patient-reported knee function. RESULTS: Seventy per cent of the swelling had occurred before application of the stocking the day...

  15. Production bias: A proposed modification of the driving force for void swelling under cascade damage conditions

    International Nuclear Information System (INIS)

    Woo, C.H.; Garner, F.A.

    1991-11-01

    A new concept of point-defect production as the main driving force for void swelling under cascade damage conditions is proposed. This concept takes into account the recombination and formation of immobile clusters and loops of vacancies and interstitials in the cascade region. The life times of the clusters and loops due to desolution are strong functions of the temperature, as well as their vacancy and interstitial nature. The resulting biased production of free point defects from the internal sources is shown to be a strong driving force for void swelling. The characteristics of void swelling due to production bias are described and compared with experimental results. We conclude that the production bias concept provides a good description of void swelling under cascade damage conditions

  16. Influence of nickel and beryllium content on swelling behavior of copper irradiated with fast neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N.; Garner, F.A.; Edwards, D.J. [Pacific Northwest National Lab., Richland, WA (United States); Evans, J.H.

    1996-10-01

    In the 1970`s, the effects of nickel content on the evolution of dislocation microstructures and the formation and growth of voids in Cu-Ni alloys were studied using 1 MeV electrons in a high voltage electron microscope. The swelling rate was found to decrease rapidly with increasing nickel content. The decrease in the swelling rate was associated with a decreasing void growth rate with increasing nickel content at irradiation temperatures up to 450{degrees}C. At 500{degrees}C, both void size and swelling rate were found to peak at 1 and 2% Ni, respectively, and then to decrease rapidly with increasing nickel content. However, recent work has demonstrated that the swelling behavior of Cu-5%Ni irradiated with fission neutrons is very similar for that of pure copper. The present experiments were designed to investigate this apparent discrepancy.

  17. Observational Evidence of Summer Shamal Swells along the West Coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Glejin, J.; SanilKumar, V.; Nair, T.M.B.; Singh, J.; Mehra, P.

    Wave data collected off Ratnagiri, West coast of India, in 2010 and 2011 are used to examine the presence of the summer shamal swells. This study also aims to understand variations in wave characteristics and associated modifications in wind sea...

  18. Lipophilic Super-Absorbent Swelling Gels as Cleaners for Use on Weapons Systems and Platforms

    Science.gov (United States)

    2011-08-18

    aimed to utilize intricate designing of lipophilic super- absorbent swelling gels through careful selection of polymer backbone and ionic components, and...have found a wide range of applications in diapers , inks and display devices, separation media, and clean up of aqueous spills. Polyelectrolyte...aims to utilize intricate designing of lipophilic super-absorbent swelling gels through careful selection of polymer backbone and ionic components, and

  19. Transitory spinal cord swelling in a 6-year-old boy with Guillain-Barre syndrome

    International Nuclear Information System (INIS)

    Delhaas, T.; Kamphuis, D.J.; Witkamp, T.D.

    1998-01-01

    A 6-year-old boy developed progressive motor weakness and areflexia. The clinical picture, combined with electrophysiological findings, indicated a diagnosis of Guillain-Barre syndrome (GBS). MRI on admission revealed spinal cord swelling and increased signal intensity within the cord. It is concluded that, since a degree of central nervous system involvement can occasionally be part of the spectrum of GBS, swelling of the spinal cord without contrast enhancement does not exclude a diagnosis of GBS. (orig.)

  20. Calculation of radiation induced swelling of uranium mononitride using the digital computer program CYGRO 2

    Science.gov (United States)

    Davison, H. W.; Fiero, I. B.

    1971-01-01

    Fuel volume swelling and clad diametral creep strains were calculated for five fuel pins, clad with either T-111 (Ta-8W-2.4Hf) or PWC-11 (Nb-1Zr-0.1C). The fuel pins were irradiated to burnups between 2.7 and 4.6%. Clad temperatures were between 1750 and 2400 F (1228 and 1589 K). The maximum percentage difference between calculated and experimentally measured values of volumetric fuel swelling is 60%.

  1. Bearing and Swelling Properties of Randomly Distributed Waste Jute Reinforced Soil

    OpenAIRE

    Ozturk, Murat; Cabalar, Ali Fırat

    2017-01-01

    In this study, waste jute, which was provided from textile companies, was investigated to define effect of waste jute on swelling and bearing behavior of the sand used. Three different water content (17, 19 and 21%) and four different waste jute addition amount at different percentages (0, 1, 2, and 3) by mass of dry soil were selected as design variables. With defined variables Swelling Ratio and California Bearing Ratio (CBR) tests were conducted. According to test results it is concluded t...

  2. Structural evaluation of fast reactor core restraint with irradiation creep-swelling opposition effects

    International Nuclear Information System (INIS)

    Kalinowski, J.E.

    1979-01-01

    Irradiation creep and swelling correlations are derived from primary loading in-reactor experiments in which irradiation creep and swelling act in the same direction. When correlation uncertainty bands are applied in core restraint evaluations, significant variability in sub-assembly behavior is predicted. For example, sub-assemblies in the outer core region where neutron flux and duct temperature gradients are significant exhibit bowing responses ranging from a creep dominated outward bow to a swelling dominated inward bow. Furthermore, solutions based on upper bound and lower bound correlation uncertainty combinations are observed to cross-over indicating that such combinations are physically unrealistic in the assessment of creep-swelling opposition effects. In order to obtain realistic upper and lower bound sub-assembly responses, judgement must be applied in the selection of creep-swelling equation uncertainty combinations. Experimental programs have been defined which will provide the needed basic as well as prototypic creep-swelling opposition data for reference and advanced sub-assembly duct alloys. The first of these is an irradiation of cylindrical capsules subjected to a through-wall temperature gradient. This test which is presently underway in the EBR-II reactor will provide the data needed to refine irradiation creep and swelling correlations and their associated uncertainties when applied to core restraint evaluations. Restrained pin and duct bowing experiments in FFTF have also been defined. These will provide the prototypic data necessary to verify irradiated duct bowing methodology. The results of this experimental program are expected to reduce creep and swelling uncertainties and permit better definition of the design window for load plane gaps. (orig.)

  3. A Simple Optical Model for the Swelling Evaluation in Polymer Nanocomposites

    Directory of Open Access Journals (Sweden)

    Anna De Girolamo Del Mauro

    2009-01-01

    In particular, the behavior of poly(2-hydroxyethyl methacrylate (PHEMA and of carbon black/PHEMA nanocomposite layers, used for volatile organic compounds (VOCs detection, was investigated and measured under ethanol vapors exposure (max 1%. The method is very sensitive and the swelling in the range of only few nanometers can be measured. Interestingly, we have found that the nanocomposite undergoes a more pronounced swelling process with respect to pristine polymer. Ethanol diffusion coefficients in the nanocomposite were evaluated.

  4. Decreased STAT3 Phosphorylation Mediates Cell Swelling in Ammonia-Treated Astrocyte Cultures

    Directory of Open Access Journals (Sweden)

    Arumugam R. Jayakumar

    2016-12-01

    Full Text Available Brain edema, due largely to astrocyte swelling, and the subsequent increase in intracranial pressure and brain herniation, are major complications of acute liver failure (ALF. Elevated level of brain ammonia has been strongly implicated in the development of astrocyte swelling associated with ALF. The means by which ammonia brings about astrocyte swelling, however, is incompletely understood. Recently, oxidative/nitrosative stress and associated signaling events, including activation of mitogen-activated protein kinases (MAPKs, as well as activation of the transcription factor, nuclear factor-kappaB (NF-κB, have been implicated in the mechanism of ammonia-induced astrocyte swelling. Since these signaling events are known to be regulated by the transcription factor, signal transducer and activator of transcription 3 (STAT3, we examined the state of STAT3 activation in ammonia-treated cultured astrocytes, and determined whether altered STAT3 activation and/or protein expression contribute to the ammonia-induced astrocyte swelling. STAT3 was found to be dephosphorylated (inactivated at Tyrosine705 in ammonia-treated cultured astrocytes. Total STAT3 protein level was also reduced in ammonia-treated astrocytes. We also found a significant increase in protein tyrosine phosphatase receptor type-1 (PTPRT-1 protein expression in ammonia-treated cultured astrocytes, and that inhibition of PTPRT-1 enhanced the phosphorylation of STAT3 after ammonia treatment. Additionally, exposure of cultured astrocytes to inhibitors of protein tyrosine phosphatases diminished the ammonia-induced cell swelling, while cultured astrocytes over-expressing STAT3 showed a reduction in the astrocyte swelling induced by ammonia. Collectively, these studies strongly suggest that inactivation of STAT3 represents a critical event in the mechanism of the astrocyte swelling associated with acute liver failure.

  5. Enhanced transduction of photonic crystal dye lasers for gas sensing via swelling polymer film

    DEFF Research Database (Denmark)

    Smith, Cameron; Lind, Johan Ulrik; Christiansen, Mads Brøkner

    2011-01-01

    We present the enhanced transduction of a photonic crystal dye laser for gas sensing via deposition of an additional swelling polymer film. Device operation involves swelling of the polymer film during exposure to specific gases, leading to a change in total effective refractive index. Experimental...... in its application to other intracavity-based detection schemes to enable gas sensing. © 2011 Optical Society of America....

  6. The Quality of Rambak Cracker from Rabbit Skin (Water Content and Swelling Power using The Different Technique of Fur Picking

    Directory of Open Access Journals (Sweden)

    Dedes Amertaningtyas

    2014-11-01

    Full Text Available This objective of this researchwas to compare the different technique of fur picking (liming and boiling inthe quality rambak cracker from rabbit skin on water content and swelling power.Materials of this research were 20 drying rabbit skin 5 – 6 months old. The tTest was using to compare the different technique of fur picking. Theindependent variables of this research were water content and swelling power onrambak cracker from rabbit skin. The result showed that the different techniqueof fur picking had highly significant effect (P<0.01 on water content and  expanding rate. The best result was limingtechnique of fur picking. It had the following properties: Water content of 1.5922% and expending rate of 855.3798 %. The conclusion showed that the use limingof 4% produced high quality of rambak cracker from rabbit skin or anotheranimal skin (cow, buffalo, chicken or fish. Keywords: rambak cracker, rabbit skin, water content,expanding rate

  7. Hygroscopic Swelling Determination of Cellulose Nanocrystal (CNC) Films by Polarized Light Microscopy Digital Image Correlation.

    Science.gov (United States)

    Shrestha, Shikha; Diaz, Jairo A; Ghanbari, Siavash; Youngblood, Jeffrey P

    2017-05-08

    The coefficient of hygroscopic swelling (CHS) of self-organized and shear-oriented cellulose nanocrystal (CNC) films was determined by capturing hygroscopic strains produced as result of isothermal water vapor intake in equilibrium. Contrast enhanced microscopy digital image correlation enabled the characterization of dimensional changes induced by the hygroscopic swelling of the films. The distinct microstructure and birefringence of CNC films served in exploring the in-plane hygroscopic swelling at relative humidity values ranging from 0% to 97%. Water vapor intake in CNC films was measured using dynamic vapor sorption (DVS) at constant temperature. The obtained experimental moisture sorption and kinetic profiles were analyzed by fitting with Guggenheim, Anderson, and deBoer (GAB) and Parallel Exponential Kinetics (PEK) models, respectively. Self-organized CNC films showed isotropic swelling, CHS ∼0.040 %strain/%C. By contrast, shear-oriented CNC films exhibited an anisotropic swelling, resulting in CHS ∼0.02 and ∼0.30 %strain/%C, parallel and perpendicular to CNC alignment, respectively. Finite element analysis (FEA) further predicted moisture diffusion as the predominant mechanism for swelling of CNC films.

  8. Fission-induced recrystallization effect on intergranular bubble-driven swelling in U-Mo fuel

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Linyun; Mei, Zhi-Gang; Yacout, Abdellatif M.

    2017-10-01

    We have developed a mesoscale phase-field model for studying the effect of recrystallization on the gas-bubble-driven swelling in irradiated U-Mo alloy fuel. The model can simulate the microstructural evolution of the intergranular gas bubbles on the grain boundaries as well as the recrystallization process. Our simulation results show that the intergranular gas-bubble-induced fuel swelling exhibits two stages: slow swelling kinetics before recrystallization and rapid swelling kinetics with recrystallization. We observe that the recrystallization can significantly expedite the formation and growth of gas bubbles at high fission densities. The reason is that the recrystallization process increases the nucleation probability of gas bubbles and reduces the diffusion time of fission gases from grain interior to grain boundaries by increasing the grain boundary area and decreasing the diffusion distance. The simulated gas bubble shape, size distribution, and density on the grain boundaries are consistent with experimental measurements. We investigate the effect of the recrystallization on the gas-bubble-driven fuel swelling in UMo through varying the initial grain size and grain aspect ratio. We conclude that the initial microstructure of fuel, such as grain size and grain aspect ratio, can be used to effectively control the recrystallization and therefore reduce the swelling in U-Mo fuel.

  9. Void swelling and defect processes in ti-modified steels using accelerator irradiation

    International Nuclear Information System (INIS)

    Nair, K.G.M.; Panigrahi, B.K.; Arunkumar, J.; David, C.; Balaji, S.; Rajaraman, R.; Ararebdram, G.; Abhaya, S.; Valsakumar, M.C.; Sunar, C.S.; Raj, B.

    2008-01-01

    The void swelling behaviour of (15Ni-14Cr)-O.25Ti and (15Ni-14Cr)-O.15Ti steels are studied using heavy ion irradiation for understanding the influence of titanium in the void swelling resistance of these D9 alloys. The cold worked samples have been pre-implanted with a uniform helium concentration of 30 appm spanning a width of about 640 nm. This was followed by a 5-MeV nickel ion irradiation to create a peak damage of ∼ 100 dpa at a damage rate of 7 x 10 -3 dpa/s at various irradiation temperatures between 700 and 970 K. The gross swelling in the implanted range is measured by step height measurements. It is found that the peak swelling temperatures and the magnitude of swelling for the alloys are different. The difference in void swelling behaviour with variation in titanium concentration in these two alloys is discussed on the basis of the role of titanium on the vacancy migration and TiC precipitate formation. Isochronal annealing study of the positron lifetime in the un-irradiated alloys reveals different TiC precipitates formation behaviour in the two alloys. Ab initio calculations of positron lifetime, using large super-cells, show that C vacancies at the TiC/austenite interface are the predominant positron trapping centres in these alloys. (authors)

  10. Modeling and Investigation of the Swelling Kinetics of Acrylamide-Sodium Acrylate Hydrogel

    Directory of Open Access Journals (Sweden)

    Azmi Seyhun Kipcak

    2014-01-01

    Full Text Available The acrylamide-sodium acrylate hydrogel was synthesized by free radical polymerization of the method of solution polymerization. Dynamic swelling tests were conducted at 25, 40, and 60°C temperatures, in order to investigate the swelling properties of the synthesized hydrogel. The results have shown that swelling content and swelling rate of the hydrogel increase with increasing the swelling water temperature. The diffusivity values changed from 1.81×10-7 to 2.97×10-7 m2 s−1 over the temperature range. The activation energies were found as 3.56, 3.71, and 3.86 kJ mol−1 at 25, 40, and 60°C, respectively. The experimental drying curves obtained were fitted to a three different models, namely, Peleg’s, first-order absorption kinetic, and exponential association equation models. All the models applied provided a good agreement with the experimental data with high values of the coefficient of determination (R2, the least values of the reduced chi-square (χ2, and root mean square error (RMSE. Comparing the determination of coefficient, reduced chi-square, and root mean square error values of three models, it was concluded that the exponential association equation model represents swelling characteristics better than the others.

  11. Ice compresses aid the reduction of swelling and pain after scleral buckling surgery.

    Science.gov (United States)

    Li, Zhuo; Wang, Qin

    2016-11-01

    To investigate the therapeutic effects of a local ice compress in alleviating eyelid swelling and errhysis and providing relief from pain after surgery. Eyelid swelling and pain are the most common postoperative symptoms after scleral buckling surgery. A local ice compress can reduce the severity of swelling, errhysis and pain after acute injury as well as after surgery. A retrospective study. A total of 100 patients who had undergone scleral buckling surgery for retinal detachment were classified into an ice compress group or a control group. All patients received standard postoperative medical care: a 1% Tropicamide ophthalmic solution (Minims ® Tropicamide; Bausch & Lomb, Surrey, UK), a 1% prednisolone acetate (Pred-Forte; Allergan, Irvine, CA, USA), an ophthalmic tobramycin 0·3%/dexamethasone 0·1% combination ointment (Tobradex ® ; Alcon, Fort Worth, Texas, USA) and 0·5% Levofloxacin eye drops (Santen Pharmaceutical, Osaka, Japan), plus a homemade ice pack was placed over the operated eye of patients in the ice compress group for 30 minutes, three times a day for two consecutive postoperative days. The severity of swelling, pain and errhysis in the operated eyes was significantly lower in the ice compress group. The local ice compress therapy helped reduce swelling, errhysis and pain in the operated eye after scleral buckling surgery. Use of a local ice compress after scleral buckling surgery can reduce swelling and pain on operated eyes, providing greater comfort for patients. © 2016 John Wiley & Sons Ltd.

  12. Mathematical modelling of liquid transport in swelling pharmaceutical immediate release tablets.

    Science.gov (United States)

    Markl, Daniel; Yassin, Samy; Wilson, D Ian; Goodwin, Daniel J; Anderson, Andrew; Zeitler, J Axel

    2017-06-30

    Oral dosage forms are an integral part of modern health care and account for the majority of drug delivery systems. Traditionally the analysis of the dissolution behaviour of a dosage form is used as the key parameter to assess the performance of a drug product. However, understanding the mechanisms of disintegration is of critical importance to improve the quality of drug delivery systems. The disintegration performance is primarily impacted by the hydration and subsequent swelling of the powder compact. Here we compare liquid ingress and swelling data obtained using terahertz pulsed imaging (TPI) to a set of mathematical models. The interlink between hydration kinetics and swelling is described by a model based on Darcy's law and a modified swelling model based on that of Schott. Our new model includes the evolution of porosity, pore size and permeability as a function of hydration time. Results obtained from two sets of samples prepared from pure micro-crystalline cellulose (MCC) indicate a clear difference in hydration and swelling for samples of different porosities and particle sizes, which are captured by the model. Coupling a novel imaging technique, such as TPI, and mathematical models allows better understanding of hydration and swelling and eventually tablet disintegration. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  13. Swelling of plutonium alloys. Measurements by optical fiber dilatometry; Gonflement des alliages de plutonium. Mesures par dilatometrie a fibre optique

    Energy Technology Data Exchange (ETDEWEB)

    Julia, P.; Gras-Naulin, N. [CEA - Centre de Valduc - 21120 Is-sur-Tille (France)

    2006-07-01

    Swelling is certainly the most remarkable effect of the plutonium alloys aging. This phenomenon has been experimentally observed as well at the macroscopic scale than at the microscopic scale on delta phase stabilized alloys. The continuous measurement of the macroscopic swelling is carried out by an original technique of Bragg lattice optical fibers dilatometry (transformation of a dimensional variation to a spectral shift). The obtained results show that the swelling begins without observing a latency period. The swelling kinetics presents two distinct phases: a transient phase followed by a linear phase. The evolution of the swelling seems to be sensitive to temperature. (O.M.)

  14. Improved Stabilities of Immobilized Glucoamylase on Functionalized Mesoporous Silica Synthesised using Decane as Swelling Agent

    Directory of Open Access Journals (Sweden)

    Reni George

    2013-06-01

    Full Text Available Ordered mesoporous silica, with high porosity was used to immobilize glucoamylase via adsorption and covalent binding. Immobilization of glucoamylase within mesoporous silica was successfully achieved, resulting in catalytically high efficiency during starch hydrolysis. In this study, mesoporous silica was functionalized by co-condensation of tetraethoxysilane (TEOS with organosilane (3-aminopropyl triethoxysilane (APTES in a wide range of molar ratios of APTES: TEOS in the presence of triblock copolymer P123 under acidic hydrothermal conditions. The prepared materials were characterized by Small angle XRD, Nitrogen adsorption – desorption and 29Si MAS solid state NMR. N2 desorption studies showed that pore size distribution decreases due to pore blockage after functionalization and enzyme immobilization. Small angle XRD and 29Si MAS NMR study reveals mesophase formation and Si environment of the materials. The main aim of our work was to study the catalytical activity, effect of pH, temperature storage stability and reusability of covalently bound glucoamylase on mesoporous silica support. The result shows that the stability of enzyme can be enhanced by immobilization.  © 2013 BCREC UNDIP. All rights reservedReceived: 3rd December 2012; Revised: 4th April 2013; Accepted: 20th April 2013[How to Cite: George, R., Gopinath, S., Sugunan, S. (2013. Improved Stabilities of Immobilized Glucoamyl-ase on Functionalized Mesoporous Silica Synthesized using Decane as Swelling Agent. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 70-76. (doi:10.9767/bcrec.8.1.4208.70-76][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4208.70-76] | View in  |

  15. The effect of low dose rate irradiation on the swelling of 12% cold-worked 316 stainless steel

    International Nuclear Information System (INIS)

    Allen, T. R.

    1999-01-01

    In pressurized water reactors (PWRs), stainless steel components are irradiated at temperatures that may reach 400 C due to gamma heating. If large amounts of swelling (>10%) occur in these reactor internals, significant swelling related embrittlement may occur. Although fast reactor studies indicate that swelling should be insignificant at PWR temperatures, the low dose rate conditions experienced by PWR components may possibly lead to significant swelling. To address these issues, JNC and ANL have collaborated to analyze swelling in 316 stainless steel, irradiated in the EBR-II reactor at temperatures from 376-444 C, at dose rates between 4.9 x 10 -8 and 5.8 x 10 -7 dpa/s, and to doses of 56 dpa. For these irradiation conditions, the swelling decreases markedly at temperatures less than approximately 386 C, with the extrapolated swelling at 100 dpa being around 3%. For temperatures greater than 386 C, the swelling extrapolated to 100 dpa is around 9%. For a factor of two difference in dose rate, no statistically significant effect of dose rate on swelling was seen. For the range of dose rates analyzed, the swelling measurements do not support significant (>10%) swelling of 316 stainless steel in PWRs

  16. Preparation of poly (2-hydroxyethyl methacrylate -co-acrylamide) hydrogels by gamma radiation: sol-gel analysis, swelling kinetic and mechanical behaviour

    International Nuclear Information System (INIS)

    Rapado Paneque, Manuel; Concepcion Villanueva, Daniel; Peniche, Carlos; Rosiak, Janusz M.

    2006-01-01

    2 hydroxyethyl methacrylate (HEMA) / acrylamide (Am) hydrogels were prepared by simultaneous radiation induced cross linking copolymerization. The G values of cross linking and degradation, gelation dose and further radiation parameters were estimated by sol/gel analysis. The dynamic swelling behaviour at 37 grade centigrade of these kind of materials was studied. The influence of the absorbed dose on the swelling degree at different pH was studied. It was observed that the kinetics is in good agreement with the second order diffusion kinetics proposed by Schott. The degree of cross linking was found to increase with the adsorbed dose and influence the mechanical properties to some extend. The molar mass of chain between the network cross links was estimated

  17. swelling characteristics and tensile properties of natural fiber rei

    African Journals Online (AJOL)

    USER

    1.0 INTRODUCTION. Composite materials comprising polymer matrices reinforced with fibers usually of glass fiber, Kevlar and carbon have gained considerable applications in automotive, aerospace, marine and construction industries (1). Glass reinforced plastic was originally developed in the United. Kingdom during the ...

  18. Investigating water absorption and thickness swelling tendencies of ...

    African Journals Online (AJOL)

    Replacing external metallic wall of refrigerated vehicles has been on the front burner in many published works as weight of the metallic insulated panel continues to pose a challenge on refrigeration unit and environment. As a follow - up to this problem statement, five (5) composite materials were fabricated as replacement ...

  19. Grewia Gum 1: Some Mechanical and Swelling Properties of ...

    African Journals Online (AJOL)

    Erah

    biodegradable films from natural polysaccharides have the potential to replace their synthetic counterparts as packaging materials and also as coatings for solid dosage forms [2]. Like proteins, natural polysaccharides are .... mL) were cast on plastic Petri dishes (150 mm in diameter) and allowed to dry in an oven at 37 oC.

  20. The Swelling of Rat Liver Mitochondria by Thyroxine and its Reversal

    Science.gov (United States)

    Lehninger, Albert L.; Ray, Betty Lou; Schneider, Marion

    1959-01-01

    The in vitro swelling action of L-thyroxine on rat liver mitochondria as examined photometrically represents an acceleration of a process which the mitochondria are already inherently capable of undergoing spontaneously, as indicated by the identical kinetic characteristics and the extent of thyroxine-induced and spontaneous swelling, the nearly identical pH dependence, and the fact that sucrose has a specific inhibitory action on both types of swelling. However, thyroxine does not appear to be a "catalyst" or coenzyme since it does not decrease the temperature coefficient of spontaneous swelling. The temperature coefficient is very high, approximately 6.0 near 20°. Aging of mitochondria at 0° causes loss of thyroxine sensitivity which correlates closely with the loss of bound DPN from the mitochondria, but not with loss of activity of the respiratory chain or with the efficiency of oxidative phosphorylation. Tests with various respiratory chain inhibitors showed that the oxidation state of bound DPN may be a major determinant of thyroxine sensitivity; the oxidation state of the other respiratory carriers does not appear to influence sensitivity to thyroxine. These facts and other considerations suggest that a bound form of mitochondrial DPN is the "target" of the action of thyroxine. The thyroxine-induced swelling is not reversed by increasing the osmolar concentration of external sucrose, but can be "passively" or osmotically reversed by adding the high-particle weight solute polyvinylpyrrolidone. The mitochondrial membrane becomes more permeable to sucrose during the swelling reaction. On the other hand, thyroxine-induced swelling can be "actively" reversed by ATP in a medium of 0.15 M KCl or NaCl but not in a 0.30 M sucrose medium. The action of ATP is specific; ADP, Mn++, and ethylenediaminetetraacetate are not active. It is concluded that sucrose is an inhibitor of the enzymatic relationship between oxidative phosphorylation and the contractility and

  1. Hydration of swelling clays: multi-scale sequence of hydration and determination of macroscopic energies from microscopic properties

    International Nuclear Information System (INIS)

    Salles, F.

    2006-10-01

    Smectites have interesting properties which make them potential candidates for engineered barriers in deep geological nuclear waste repository: low permeability, swelling and cations retention. The subject of this thesis consists in the determination of the relationship between hydration properties, swelling properties and cations mobility in relation with confinement properties of clayey materials. The aim is to understand and to predict the behaviour of water in smectites, following two research orientations: the mechanistic aspects and the energetic aspects of the hydration of smectites. We worked on the Na-Ca montmorillonite contained in the MX80 bentonite, with the exchanged homo ionic structure (saturated with alkaline cations and calcium cations). The approach crosses the various scales (microscopic, mesoscopic and macroscopic) and implied the study of the various components of the system (layer-cation-water), by using original experimental methods (thermo-poro-metry and electric conductivity for various relative humidities (RH) and electrostatic calculations. Initially, the dry state is defined by SCTA (scanning calorimetry thermal analysis). Then a classical characterization of the smectite porosity for the dry state is carried out using mercury intrusion and nitrogen adsorption. We evidenced the existence of a meso-porosity which radius varies from 2 to 10 nm depending on the compensating cation. The thermo-poro-metry and conductivity experiments performed at various hydration states made it possible to follow the increase in the pore sizes and the cations mobility as a function of the hydration state. We highlight in particular the existence of an osmotic mesoscopic swelling for low RH (approximately 50-60%RH for Li and Na). By combining the results of thermo-poro-metry, X-ray diffraction and electric conductivity, we are able to propose a complete hydration sequence for each cation, showing the crucial role of the compensating cation in the hydration of

  2. [Species Determination and Spectral Characteristics of Swelling Clay Minerals in the Pliocene Sandstones in Xinghai, Qinghai].

    Science.gov (United States)

    Wang, Chao-wen; Chen, Jiang-jun; Fang, Qian; Yin, Ke; Hong, Han-lie

    2015-10-01

    X-ray diffraction (XRD) and Fourier infrared absorption spectroscopy (FTIR) were conducted to deepen our research on specific species and spectral characteristics of swelling clay minerals in the Pliocene sandstones in Xinghai, Qinghai province. XRD results show that swelling clay minerals are dominant clay minerals in the sandstones, which can be up to 97% in percentage. XRD patterns show 060 reflections of the samples occur both remarkably at 1.534 Å and 1.498 Å, indicating the samples contain physical mixtures of trioctahedral and dioctahedral swelling clay minerals, respectively. Further treatment of Li-300 degrees C heat and glycerol saturation shows the swelling clay minerals collapse to 9.3-9.9 Å with a partial expansion to -18 Å. This indicates the swelling clay minerals dominate montmorillonite and contain minor saponite. The montmorillonite shows no swelling after Li-300 degrees C heat and glycerol saturation because of Li+ inserting into the octahedral layers, which balances the layer charge caused by the substitution of Mg to Al. FTIR results show the samples are composed of a kind of phyllosilicate with absorbed and structural water, which is in agreement with the results of XRD. Absorbed peaks at 913, 842, 880 cm(-1), corresponding to OH associated with Al-Al, Al-Mg, and Al-Fe pairs, further indicates the minerals are dominant dioctahedron in structure. Meanwhile, absorbed peaks at 625 and 519 cm(-1), corresponding to coupled Si-O and Al-O-Si deformation, indicates parts of Si is replaced by Al in tetrahedron. The spectral characteristics of the samples are against the presence of beidellite and nontronite based on the results of XRD and FTIR, while demonstrating an,existence of montmorillonite. This study, to distinguish the specific species of swelling clay species in clay minerals, would be of great importance when using clay mineralogy to interpret provenance and climatic information.

  3. Applications of simulation experiments in LMFBR core materials technology

    International Nuclear Information System (INIS)

    Appleby, W.K.

    1976-01-01

    The development of charged particle bombardment experiments to simulate neutron irradiation induced swelling in austenitic alloys is briefly described. The applications of these techniques in LMFBR core materials technology are discussed. It is shown that use of the techniques to study the behavior of cold-worked Type-316 was instrumental in demonstrating at an early date the need for advanced materials. The simulation techniques then were used to identify alloying elements which can markedly decrease swelling and thus a focused reactor irradiation program is now in place to allow the future use of a lower swelling alloy for LMFBR core components

  4. Effects of irradiation on four solid breeder materials

    International Nuclear Information System (INIS)

    Hollenberg, G.W.

    1984-01-01

    The tritium breeding material with the highest lithium atom density, Li 2 O has been observed to incur significant swelling (>4%) under fast reactor irradiation. Such swelling, if unrestrained leads to either unacceptable, induced-strains in adjacent structural material or undesirable design compromises. Fortunately, however, Li 2 O deforms at low temperatures so that swelling strains may be internally accommodated. Laboratory dilational creep experiments were conducted on unirraciated Li 2 O between 500 and 700 0 C in order to provide data for structural analysis of in-reactor experiments and blanket design studies. A densification model agreed with most of the available data. 15 refs

  5. Gas swelling behaviour at different stages in Li4Ti5O12/LiNi1/3Co1/3Mn1/3O2 pouch cells

    Science.gov (United States)

    Liu, Wei; Liu, Haohan; Wang, Qian; Zhang, Jian; Xia, Baojia; Min, Guoquan

    2017-11-01

    Gas swelling behaviour is a major drawback of batteries that are based on Li4Ti5O12 anode materials and hinders their application. In this article, the morphology and electronic structure changes of Li4Ti5O12 electrodes at ageing and cycling stages are investigated using scanning electron microscopy, X-ray absorption near-edge structure and X-ray photoelectron spectroscopy. A simple method that uses an air bag to collect the generated gases was conducted and the gases were then characterised by gas chromatography/mass spectrometry. The results indicate that the charge transformation of Ti ions would aggravate the gas swelling behaviour. The solid electrolyte interphase (SEI) films form on the surface of the Li4Ti5O12 particles and become thicker with increasing charge state. The gas components change significantly during the ageing and cycling, indicating the complexity of the gas swelling mechanism.

  6. Results of the freeze resistance test, swelling index and coefficient of permeability of finegrained mining waste reinforced with cements

    Science.gov (United States)

    Morman, Justyna

    2018-04-01

    The article presents the result of laboratory tests for mining waste with grain size of 0 to 2 mm stabilized with cement. Used for stabilization of cement CEM I 42.5 R and blast furnace cement CEM III / A 42.5N - LH / HSR / NA and a plasticizer sealant. Cement was added to the mining waste test in the proportions of 5 - 8% in relation to the skeleton's weight. For the cemented samples, the freeze resistance test, swelling index, coefficient of permeability and pH of water leachate were tested. The addition of a cement binder resulted in diminishing the water permeability of mining waste and limiting the leaching of fine particles from the material.

  7. Prediction of void swelling in the baffle ring of WWER-1000 reactors for service life of 30-60 years

    Science.gov (United States)

    Kalchenko, A. S.; Bryk, V. V.; Lazarev, N. P.; Voyevodin, V. N.; Garner, F. A.

    2013-06-01

    Major internal components of WWER-type nuclear reactors are made from annealed 18Cr10NiTi steel, a close analog to AISI 321. Void swelling of the baffle ring in particular could be a major factor limiting operation of the reactor beyond the current 30 years license. A predictive swelling equation is needed to forecast the spatial variation of swelling so as to identify those areas requiring additional attention. Available data on the swelling of this steel arising from irradiation in the BOR-60 fast reactor was combined with data from a heavy ion accelerator at higher displacement rates to formulate a predictive equation of swelling for the WWER-relevant range of temperature, irradiation dose and dose rates. This equation was used to estimate the swelling distribution over a cross-section of the baffle ring of a WWER reactor during a service life up to 60 years, reaching a local maximum of ˜30% swelling. It was shown that void swelling extends over a larger portion of the baffle ring than previously expected and exhibits a very complex and irregular distribution in response to complex distributions of temperature and dpa rate. Most importantly, as operation is extended beyond 30 years several areas of the ring may experience swelling in excess of 10% where void-induced embrittlement begins and one area may exceed 20% after 45 years, a swelling level where a complete loss of ductility is known to occur.

  8. A novel multiphysic model for simulation of swelling equilibrium of ionized thermal-stimulus responsive hydrogels

    International Nuclear Information System (INIS)

    Li Hua; Wang Xiaogui; Yan Guoping; Lam, K.Y.; Cheng Sixue; Zou Tao; Zhuo Renxi

    2005-01-01

    In this paper, a novel multiphysic mathematical model is developed for simulation of swelling equilibrium of ionized temperature sensitive hydrogels with the volume phase transition, and it is termed the multi-effect-coupling thermal-stimulus (MECtherm) model. This model consists of the steady-state Nernst-Planck equation, Poisson equation and swelling equilibrium governing equation based on the Flory's mean field theory, in which two types of polymer-solvent interaction parameters, as the functions of temperature and polymer-network volume fraction, are specified with or without consideration of the hydrogen bond interaction. In order to examine the MECtherm model consisting of nonlinear partial differential equations, a meshless Hermite-Cloud method is used for numerical solution of one-dimensional swelling equilibrium of thermal-stimulus responsive hydrogels immersed in a bathing solution. The computed results are in very good agreements with experimental data for the variation of volume swelling ratio with temperature. The influences of the salt concentration and initial fixed-charge density are discussed in detail on the variations of volume swelling ratio of hydrogels, mobile ion concentrations and electric potential of both interior hydrogels and exterior bathing solution

  9. Swelling kinetics and impregnation of PLA with thymol under supercritical CO2 conditions

    Directory of Open Access Journals (Sweden)

    Milovanović Stoja L.

    2016-01-01

    Full Text Available The present work was aimed to study swelling kinetics of polylactic acid (PLA and its impregnation with thymol in supercritical carbon dioxide (scCO2 medium. The influences of temperature and soaking time on the swelling kinetics and impregnation yield of PLA cylindrical disc and film were investigated. Swelling experiments were performed in a high pressure view cell at 10 MPa and temperatures of 40°C, 60°C and 75°C for 2 to 24 h. On the basis of swelling kinetics, pressure of 10 MPa and temperature of 40°C were chosen for supercritical solvent impregnation (SSI of the PLA samples during 2 to24 h. The highest swelling extent was observed for the PLA monolith after 24 h treatment with pure scCO2 (7.5% and scCO2 with thymol (118.3%. It was shown that sufficiently high amount of thymol can be loaded into both PLA monolith and film using SSI after only 2 h (10.0% and 6.6%, respectively. Monolith and film of PLA impregnated with thymol could be suitable for active food packaging and sterile medical disposables.

  10. Applications of the theory of cavity growth to dual-ion swelling experiments

    International Nuclear Information System (INIS)

    Hayns, M.R.; Mansur, L.K.

    1980-01-01

    The rate theory of cavity growth is applied to study the effects of helium gas on cavity swelling. The variation of swelling with temperature is emphasized: (1) expressions are derived showing that the primary effect of the helium is in pressurizing cavities and that a secondary effect is in altering the microstructural sink strengths. The expressions simplify in the parameter range of engineering interest such that the temperature regime of swelling is predicted to shift upward in approximately direct proportion to the cavity gas pressure; (2) recent experimental data on swelling of a pure stainless steel type alloy under dual-nickel and helium-ion bombardment is interpreted. Helium-free, helium-coimplanted, and helium-preimplanted swelling results can be explained by the theory. It is necessary to account for the partitioning of the helium to dislocations as well as to cavities in order to explain the experimental results for helium coimplantation; (3) model studies for physically reasonable parameters reveal the importance of the He/dpa ratio

  11. Poststroke hand swelling and oedema: prevalence and relationship with impairment and disability.

    Science.gov (United States)

    Boomkamp-Koppen, H G M; Visser-Meily, J M A; Post, M W M; Prevo, A J H

    2005-08-01

    To examine the prevalence of swelling and oedema of the hand in stroke patients and relationships with impairments and disability. Cross-sectional. Stroke unit at Rehabilitation Centre De Hoogstraat, The Netherlands. Eighty-eight adult stroke patients who were admitted for clinical rehabilitation during one year (2000). Assessment took place two weeks after admission to the rehabilitation centre. Degree of swelling was measured with a hand volumeter and oedema was defined as a volumeter score deviating more than two standard deviations from the expected score derived from population data. Further assessment included tonus (Modified Ashworth Score), sensibility, tactile inattention, carefulness, and motor function (Utrecht Arm/Hand Test). Arm disability was measured with Frenchay Arm Test and Nine-hole Peg Test. Some degree of hand swelling was present in 72.7% and oedema in 33.0% of our patients. Swelling and oedema were significantly more often seen in patients with hypertonic fingers and impaired sensibility. Patients with hand oedema had significantly worse Frenchay Arm Test and Nine-hole Peg Test scores. Swelling and oedema of the hand are common among stroke patients in clinical rehabilitation.

  12. Effect of light impurities on the early stage of swelling in austenitic stainless steel

    International Nuclear Information System (INIS)

    Igata, N.

    1998-01-01

    The objective of this study is to analyse the early stage of swelling and clarify the role of light impurities (nitrogen) in swelling of austenitic stainless steel. Recent results show that light impurities affect the swelling of 316 stainless steel under HVEM irradiation up to 10 dpa. At low concentration of light impurities the radiation swelling increases then decreases through the maximum as the concentration of light impurities increases. In the present paper the theoretical model is presented for the explanation of this effect. The model is based on the two factors: the influence of absorbed impurities on the voids caused by the production of an additional gas pressure in voids for their stabilization and the effect of impurities segregated around the surface of voids by the lowering of surface tension. These two affects are taken into account in the calculations of the critical size and the growth rate of cavities. The theoretical predictions on the radiation swelling rate dependent on the impurity concentration and temperature coincided with the experimental results on 316 stainless steel irradiated by HVEM. (orig.)

  13. Swelling, Mechanics, and Thermal/Chemical Stability of Hydrogels Containing Phenylboronic Acid Side Chains

    Directory of Open Access Journals (Sweden)

    Arum Kim

    2017-12-01

    Full Text Available We report here studies of swelling, mechanics, and thermal stability of hydrogels consisting of 20 mol % methacrylamidophenylboronic acid (MPBA and 80 mol % acrylamide (AAm, lightly crosslinked with methylenebisacrylamide (Bis. Swelling was measured in solutions of fixed ionic strength, but with varying pH values and fructose concentrations. Mechanics was studied by compression and hold. In the absence of sugar or in the presence of fructose, the modulus was mostly maintained during the hold period, while a significant stress relaxation was seen in the presence of glucose, consistent with reversible, dynamic crosslinks provided by glucose, but not fructose. Thermal stability was determined by incubating hydrogels at pH 7.4 at room temperature, and 37, 50, and 65 °C, and monitoring swelling. In PBS (phosphate buffered saline solutions containing 9 mM fructose, swelling remained essentially complete for 50 days at room temperature, but decreased substantially with time at the higher temperatures, with accelerated reduction of swelling with increasing temperature. Controls indicated that over long time periods, both the MPBA and AAm units were experiencing conversion to different species.

  14. Multipurpose Compensation Scheme for Voltage Sag/Swell and Selective Harmonics Elimination in Distribution Systems

    Directory of Open Access Journals (Sweden)

    Mustafa Inci

    2018-01-01

    Full Text Available Voltage harmonics, sag, and swell are the most harmful disturbances in distribution systems. This paper introduces a novel effective controller method for simultaneous compensation of both voltage sag/swell and voltage harmonics by using multifunctional dynamic voltage restorer. In proposed controller method called FFT with integrated ISRF, ISRF detects the magnitudes of voltage sag/swell quickly and precisely, and FFT extracts the selective components of voltage harmonics very effectively. The proposed method integrates the superior properties of ISRF and FFT methods. FFT integrated ISRF is applied for the first time to provide the compensation of both sag/swell and selective harmonics together. The proposed system has ability to compensate symmetrical/asymmetrical sag/swell and symmetrical/asymmetrical selective harmonics which are 5th, 7th, 11th and 13th. The controlled system is modelled in PSCAD/EMDTC and compared with conventional methods. The performance results verify that the proposed method compensates voltage disturbances effectively in the system.

  15. Stress state dependence of in-reactor creep and swelling. Part 2: Experimental results

    Science.gov (United States)

    Hall, M. M., Jr.; Flinn, J. E.

    2010-01-01

    Irradiation creep constitutive equations, which were developed in Part I, are used here to analyze in-reactor creep and swelling data obtained ca. 1977-1979 as part of the US breeder reactor program. The equations were developed according to the principles of incremental continuum plasticity for the purpose of analyzing data obtained from a novel irradiation experiment that was conducted, in part, using Type 304 stainless steel that had been previously irradiated to significant levels of void swelling. Analyses of these data support an earlier observation that all stress states, whether tensile, compressive, shear or mixed, can affect both void swelling and interactions between irradiation creep and swelling. The data were obtained using a set of five unique multiaxial creep-test specimens that were designed and used for the first time in this study. The data analyses demonstrate that the constitutive equations derived in Part I provide an excellent phenomenological representation of the interactive creep and swelling phenomena. These equations provide nuclear power reactor designers and analysts with a first-of-its-kind structural analysis tool for evaluating irradiation damage-dependent distortion of complex structural components having gradients in neutron damage rate, temperature and stress state.

  16. Water swelling properties of the electron beam irradiated PVA-g-AAc hydrogels

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qingguo, E-mail: qwang@qust.edu.cn [Key Laboratory of Rubber-Plastics of Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042 (China); Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao 266042 (China); Zhou, Xue; Zeng, Jinxia; Wang, Jizeng [Key Laboratory of Rubber-Plastics of Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042 (China)

    2016-02-01

    In this paper, the electron beam irradiation technology being more suitable for the industry application is explored to fabricate the acrylic acid (AAc) monomer-grafted polyvinyl alcohol (PVA-g-AAc) hydrogels. ATR-IR spectra of the PVA-g-AAc hydrogels shows an obvious absorption peak of the −C=O group at 1701 cm{sup −1}, indicating that the AAc monomers were grafted onto the PVA macromolecules. This paper also studied some effects of the mass ratio of PVA/AAc, pH of buffer solution and irradiation dosage on the water swelling properties of the electron beam irradiated PVA-g-AAc hydrogels. The water swelling ratio of PVA-g-AAc hydrogels decreases with increased irradiation dosage and mass ratio of PVA/AAc, whereas swelling ratio increases with increased pH of buffer solution and soaking time. The water-swelling behavior of PVA-g-AAc hydrogels occurred easily in an alkaline environment, particularly in a buffer solution with pH 9.2. Both PVA-g-AAc hydrogels (PVA/AAc = 1/5, w/w) irradiated with 5 kilogray (kGy) and PVA-g-AAc hydrogels (PVA/AAc = 1/1, w/w) irradiated with 15 kGy could easily absorb water and lead to high water swelling ratios (up to about 600%), which are potential candidates to meet the requirements for some biomedical applications.

  17. Acute swelling of the limbs: magnetic resonance pictorial review of fascial and muscle signal changes

    Energy Technology Data Exchange (ETDEWEB)

    Revelon, Geraldine [Department of Radiology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Rahmouni, Alain [Department of Radiology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Jazaerli, Nedal [Department of Radiology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Godeau, Bertrand [Department of Internal Medicine, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Chosidow, Olivier [Department of Dermatology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Authier, Jerome [Department of Pathology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Mathieu, Didier [Department of Radiology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Roujeau, Jean-Claude [Department of Dermatology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France); Vasile, Norbert [Department of Radiology, Centre Hospitalo-Universitaire Henri Mondor, 51 Avenue du Marechal De Lattre De Tassigny, 94000 Creteil (France)

    1999-04-01

    Objective: This pictorial review analyzes the magnetic resonance (MR) fascial/muscular changes in 69 patients referred as emergencies with acute swelling of the limbs (ASL) from various causes. Methods and material: A prospective MR imaging (MRI) study of 69 patients referred as emergencies for ASL was performed. Our population consisted of 45 patients with skin and soft-tissue infections (cellulitis and necrotizing fasciitis, and pyomyositis), six patients with soft-tissue inflammatory diseases (dermatomyositis, graft-versus-host disease), 11 patients with acute deep venous thrombosis, three patients with rhabdomyolysis, one patient with acute denervation and three other patients with rare diseases. Hematomas, tumorous or infectious bone involvement and soft-tissue tumors were excluded. All studies included spin echo T1-weighted images and spin echo T2-weighted images. Gadolinium-enhanced spin echo T1-weighted images were obtained when an abscess was suspected on T2-weighted images. Selective fat-saturated T1- and T2-weighted sequences were also used. MRI analysis was performed to obtain a compartmentalized anatomical approach according to the location of signal abnormalities in subcutaneous fat, superficial and deep fascia and muscle. Results: In all patients with ASL, MRI demonstrated soft-tissue abnormalities involving subcutaneous fat, superficial fascia, deep fascia, or muscle. Although MR findings were non-specific, MRI appears sensitive for detecting subtle fascial and muscle signal changes. Conclusions: In skin and soft-tissue infections, MRI can be helpful for therapeutic management by determining the depth of soft-tissue involvement, particularly within fasciae and muscles, which is partly related to the severity of cellulitis with severe systemic manifestations. MRI can also aid the surgeon in diagnosing abscesses. In inflammatory diseases, MRI can determine the best site for biopsy and also monitor therapeutic response.

  18. Acute swelling of the limbs: magnetic resonance pictorial review of fascial and muscle signal changes

    International Nuclear Information System (INIS)

    Revelon, Geraldine; Rahmouni, Alain; Jazaerli, Nedal; Godeau, Bertrand; Chosidow, Olivier; Authier, Jerome; Mathieu, Didier; Roujeau, Jean-Claude; Vasile, Norbert

    1999-01-01

    Objective: This pictorial review analyzes the magnetic resonance (MR) fascial/muscular changes in 69 patients referred as emergencies with acute swelling of the limbs (ASL) from various causes. Methods and material: A prospective MR imaging (MRI) study of 69 patients referred as emergencies for ASL was performed. Our population consisted of 45 patients with skin and soft-tissue infections (cellulitis and necrotizing fasciitis, and pyomyositis), six patients with soft-tissue inflammatory diseases (dermatomyositis, graft-versus-host disease), 11 patients with acute deep venous thrombosis, three patients with rhabdomyolysis, one patient with acute denervation and three other patients with rare diseases. Hematomas, tumorous or infectious bone involvement and soft-tissue tumors were excluded. All studies included spin echo T1-weighted images and spin echo T2-weighted images. Gadolinium-enhanced spin echo T1-weighted images were obtained when an abscess was suspected on T2-weighted images. Selective fat-saturated T1- and T2-weighted sequences were also used. MRI analysis was performed to obtain a compartmentalized anatomical approach according to the location of signal abnormalities in subcutaneous fat, superficial and deep fascia and muscle. Results: In all patients with ASL, MRI demonstrated soft-tissue abnormalities involving subcutaneous fat, superficial fascia, deep fascia, or muscle. Although MR findings were non-specific, MRI appears sensitive for detecting subtle fascial and muscle signal changes. Conclusions: In skin and soft-tissue infections, MRI can be helpful for therapeutic management by determining the depth of soft-tissue involvement, particularly within fasciae and muscles, which is partly related to the severity of cellulitis with severe systemic manifestations. MRI can also aid the surgeon in diagnosing abscesses. In inflammatory diseases, MRI can determine the best site for biopsy and also monitor therapeutic response

  19. Superabsorbent hydrogel made of NaAlg-g-poly(AA-co-AAm) and rice husk ash: Synthesis, characterization, and swelling kinetic studies.

    Science.gov (United States)

    Gharekhani, Hamed; Olad, Ali; Mirmohseni, Abdolreza; Bybordi, Ahmad

    2017-07-15

    The sodium alginate-g-poly(acrylic acid-co-acrylamide)/rice husk ash (NaAlg-g-P(AA-co-AAm)/RHA) superabsorbent nanocomposite was synthesized by the free-radical graft copolymerization of alginate (NaAlg), acrylic acid (AA), acrylamide (AAm), and RHA in aqueous solution. FTIR spectra revealed that the monomers were grafted onto NaAlg chains, and the nanocomposite was formed successfully. Incorporation of RHA into hydrogel matrix formed porous interlinked channels within hydrogel network. Superabsorbent nanocomposite showed greater equilibrium swelling capacity (1070g/g) compared with neat hydrogel (830g/g). Moreover, water transport mechanism of all hydrogels was non-Fickian diffusion type. Rheological measurements confirmed effective role of RHA in improving gel strength of superabsorbent nanocomposite. The influence of various factors, such as different loads (0.3, 0.6, 0.9 psi), solution pH, saline solution, and temperature on the swelling behavior of hydrogels was also assessed. Superabsorbent nanocomposite exhibited good pH-dependent swelling reversibility and high water retention capability, making it more efficient water-saving material for agricultural and horticultural applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. An X-ray tomography study of the influence of hydration on multiscale organization of swelling clay

    International Nuclear Information System (INIS)

    Pret, D.; Faurel, M.; Ferrage, E.; Tertre, E.; Pelletier, M.; Bihannic, I.; Villieras, F.; Robinet, J.C.

    2010-01-01

    Document available in extended abstract form only. For clay based materials, studying the organization of mineral skeleton and pore space as well as water distribution remains a key and challenging task. This is needed to fully understand and model their macroscopic hydro-mechanical or transport properties. Especially when swelling clay minerals are involved, such materials are well known to represent spatially heterogeneous and anisotropic media from the nanometre (i.e., the crystal/interlayer scale) to the centimetre scale (i.e., the sample size involved in macroscopic experiments). Probing their organization over this extremely large scale range requires the combination of different techniques providing quantitative results feeding global balances. As clay organization depends on the resin used during embedding process or on content/composition of pore water, the coupling of different techniques is possible only when similar environmental conditions are used. Moreover, constraints on data acquisition or treatment actually does not allow the quantitative study of water saturated and compacted clay samples by electron microscopy or X-ray diffraction, i.e., in the main organization state involved in nuclear waste repositories. A preliminary, technically possible but still challenging task is to couple different methods quantitatively for studying the impact of hydration on organization at different scales of unsaturated samples. In addition of the cross-validation of the methods used, constraints on organization and processes involved just below water-saturation conditions could be provided. An alternative way for the study of the impact of hydration at different organization scales is to use the same technique, here the laboratory or synchrotron-based X-ray tomography, on different controlled macroscopic samples which mimic either only one swelling crystal (here a mono-crystal of vermiculite) or one oriented clay powder grain (here a mono-aggregate of purified MX

  1. Swelling of radiation crosslinked acrylamide-based microgels and their potential applications

    Energy Technology Data Exchange (ETDEWEB)

    Abd El-Rehim, H.A. [National Center for Radiation Research and Technology, Atomic Energy Authority, P.O. Box 29 Nasr City, Cairo (Egypt)]. E-mail: ha_rehim@hotmail.com

    2005-10-01

    Crosslinked polyacrylamide PAAm and acrylamide-Na-acrylate P(AAm-Na-AAc) microgels were prepared by electron beam irradiation. It was found that the dose required for crosslinking depends on the polymer moisture content, so that the dose to obtain PAAm of maximum gel fraction was over 40 and 20 kGy for dry and moist PAAm, respectively. The structural changes in irradiated PAAm were investigated using FTIR and SEM. The swelling property of such microgels in distilled water and real urine solution was determined and crosslinked polymers reached their equilibrium swelling state in a few minutes. As the gel content and crosslinking density decrease, the swelling of the microgels increases. The ability of the microgels to absorb and retain large amount of solutions suggested their possible uses in horticulture and in hygienic products such as disposable diapers.

  2. Effect of a shallow low-viscosity zone on the formation of midplate swells

    Science.gov (United States)

    Robinson, E. M.; Parsons, B.

    1988-01-01

    A finite-element numerical method is used here to analyze the effect of a low-viscosity zone on convection driven by heating from below in the upper mantle, in particular on the formation of midplate swells. The convective temperature and velocity solutions are calculated for different combinations of the viscosity in the top layer, the fluid layer thicknesses, and the Rayleigh number based on the viscosity in the bottom layer. The temperature solutions are used to calculate the geoid, topography, and heat flow anomalies, the elastic plate thickness, the depth of compensation, and an upper bound on the uplift time that result from the flow. The results are compared to data at the Hawaii, Bermuda, Cape Verde, and Marquesas swells. The magnitudes and the trend with age are consistent with theoretical and other estimates of the viscosity variation in the shallow upper mantle. Convective models can therefore explain the uplift and observed anomalies at midplate swells.

  3. Bearing and Swelling Properties of Randomly Distributed Waste Jute Reinforced Soil

    Directory of Open Access Journals (Sweden)

    Murat Ozturk

    2017-10-01

    Full Text Available In this study, waste jute, which was provided from textile companies, was investigated to define effect of waste jute on swelling and bearing behavior of the sand used. Three different water content (17, 19 and 21% and four different waste jute addition amount at different percentages (0, 1, 2, and 3 by mass of dry soil were selected as design variables. With defined variables Swelling Ratio and California Bearing Ratio (CBR tests were conducted. According to test results it is concluded that minimum swelling ratio was observed in the test containing 3% jute with 19% water content and the highest value of CBR was observed in the sample containing 2% jute with 16% water content. In addition to that, CBR values of unreinforced samples were decreased when water content increased from 16% to 21%. However, CBR values of reinforced samples increased with increasing water content from 19% to 21%.

  4. Pore pressure and swelling in the rim region of LWR high burnup UO2 fuel

    International Nuclear Information System (INIS)

    Koo, Yang-Hyun; Lee, Byung-Ho; Cheon, Jin-Sik; Sohn, Dong-Seong

    2001-01-01

    Based on measured rim characteristics of LWR high burnup UO 2 fuel, the pressure of rim pores and the additional pellet swelling due to rim formation have been modeled. Using the assumption that the number of Xe atoms retained in the rim pores is the same as that which is depleted from the rim matrix, excessive pore pressure is derived as a function of temperature, pellet average burnup and pore radius. The rim pores with small radii are calculated to be highly overpressurized at high burnup. Comparison with experimental data shows that, while the pellet swelling obtained with best-estimate rim width is underpredicted, the one calculated with conservative rim width agrees well with the measured data for rim burnups between 50 and 65 GWd/tU. On the other hand, the measured swelling at 85 GWd/tU is about in-between the two calculations

  5. Tensile, swelling and morphological properties of bentonite-filled acrylonitrile butadiene rubber composites

    Science.gov (United States)

    Lotfi, Muhamad Nadhli Amin; Ismail, Hanafi; Othman, Nadras

    2017-10-01

    Tensile, swelling and morphological properties of bentonite filled acrylonitrile butadiene rubber (NBR/Bt) composites were studied. The experiments were conducted at room temperature by using two rolled mill, universal testing machine (INSTRON), and American Standard Testing Method (ASTM) D471 for compounding, tensile testing, and swelling test, respectively. Results obtained indicated that a better tensile strength, elongation at break and tensile modulus were recorded as compared to the pure NBR particularly up to 90 phr of Bt loading. However, swelling (%) exhibited the opposite trend where the liquid uptake by the composites was indirectly proportional with the increasing of Bt loading. Scanning electron microscopy (SEM) used on the tensile fractured surface of the NBR/Bt composites have shown that the fillers were well embedded in the NBR matrix, for Bt loading up to 90 phr. The agglomeration of fillers occurred for Bt loading exceeding 90 phr.

  6. Water uptake, migration and swelling characteristics of unsaturated and saturated, highly compacted bentonite

    International Nuclear Information System (INIS)

    Pusch, R.

    1980-09-01

    The report presents the results of a number of laboratory tests and field observations to form the basis of a physical and mathematical model that can be used for predicting water uptake and swelling in highly compacted bentonite components of an actual deposition plant. The clay buffer masses have been suggested as barriers in the Swedish KBS concepts. Two commercially available bentonites were used for the production of samples. The rate of water uptake suggests a mathematical model based on a simple diffusion equation. The rate is determined by the access of water and thousands of years may pass before saturation is obtained. The rate of swelling is governed by the negative pore pressure and the permeability. There is reasonable agreement with field observations. The observed swelling potential of old smectite-rich clays has offered the evidence. (G.B.)

  7. Adsorption and strain: The CO{sub 2}-induced swelling of coal

    Energy Technology Data Exchange (ETDEWEB)

    Vandamme, M.; Brochard, L.; Lecampion, B.; Coussy, O. [Universite Paris-Est, Champs Sur Marne (France)

    2010-10-15

    Enhanced coal bed methane recovery (ECBM) consists in injecting carbon dioxide in coal bed methane reservoirs in order to facilitate the recovery of the methane. The injected carbon dioxide gets adsorbed at the surface of the coal pores, which causes the coal to swell. This swelling in confined conditions leads to a closure of the coal reservoir cleat system, which hinders further injection. In this work we provide a comprehensive framework to calculate the macroscopic strains induced by adsorption in a porous medium from the molecular level. Using a thermodynamic approach we extend the realm of poromechanics to surface energy and surface stress. We then focus on how the surface stress is modified by adsorption and on how to estimate adsorption behavior with molecular simulations. The developed framework is here applied to the specific case of the swelling of CO{sub 2}-injected coal, although it is relevant to any problem in which adsorption in a porous medium causes strains.

  8. Finite Element Investigations on the Interaction between a Pile and Swelling Clay

    DEFF Research Database (Denmark)

    Kaufmann, Kristine Lee; Nielsen, Benjaminn Nordahl; Augustesen, Anders Hust

    of Little Belt Clay. The case study involves a circular concrete pile installed in clay immediately after an excavation. The influence of the swelling soil on the soil–pile interaction and the internal pile forces are analysed by solely observing the upper pile part positioned in the swelling zone......This paper aims to investigate the interaction between a pile and a swelling soil modelled as a cohesive soil subjected to unloading. The investigations include analyses of the heave of the excavation level, shear stresses at the soil–pile interface and internal pile forces based on a case study...... of the surrounding soil implies upward shear stresses at the soil–pile interface leading to tensile vertical stresses in the pile. In the current case, they exceed the tensile strength of concrete. The tensile vertical stresses peak after 35-50 years. However, the heave of the soil continues for additional 300 years...

  9. Corticosteroid transdermal delivery to target swelling, edema and inflammation following facial rejuvenation procedures.

    Science.gov (United States)

    Iannitti, T; Rottigni, V; Palmieri, B

    2013-01-01

    The use of transdermal therapeutic systems has spread worldwide since they allow effective local drug delivery. In the present study, we investigated the efficacy and safety of a new betamethasone valerate medicated plaster (Betesil®) to manage facial swelling, edema, inflammation, ecchymosis, and hematoma, when applied immediately after a facial rejuvenation procedure. We applied the plaster to the skin of 20 healthy patients for 12 hours immediately after hyaluronic acid-based procedure performed with the aim of erasing facial wrinkles of perioral and nasolabial folds and improving chin and eye contour. A further 20 patients underwent the same cosmetic procedure, but they were treated with an aescin 10% cream (applied immediately after the procedure, in the evening, and the morning after) and served as control group. Betesil® application resulted in a significant improvement in swelling/edema/inflammation score, if compared with aescin 10% cream (P cosmetic procedures in order to safely control swelling, edema, and inflammation.

  10. Effects of minor alloying additions on the strength and swelling behavior of an austenitic stainless steel

    International Nuclear Information System (INIS)

    Gessel, G.R.

    1978-06-01

    A set of 32 alloys consisting of various additions of the elements Mo, W, Al, Ti, Nb, C and Si to an Fe-7.5 Cr-20 Ni alloy were made in order to investigate the effects of these solute additions on alloy swelling and strength. Both single and multiple additions were examined. The influence of various solute elements on the swelling behavior in the range 500 to 730 0 C was investigated using 4 MeV Ni ion bombardment to a dose 170 dpa. It was found that on an atomic percent basis, the elements may be arranged in order of decreasing effectiveness in reducing peak temperature swelling as follows: Ti, C, Nb, Si, and Mo. Small amounts of aluminum enhance swelling. Additions of Si, Ti, or Nb truncate the high temperature swelling regime of the ternary alloy. Mo, W, and C do not have a strong effect on the temperature dependence of swelling. The results may be interpreted in terms of the effect of point defect trapping on void growth rates, and it is suggested that the changes in peak temperature are the result of small changes in the free vacancy formation energy. A method for treating certain multiple additions is proposed. The effect of these alloying additions on short time high temperature strength properties was estimated using hot hardness measurements over the temperature range 22 to 850 0 C. On an atom percent basis Nb and Ti were most effective in conferring solid solution strengthening and Si the least effective. In the regime 22 to approximately 650 0 C, the hardness data was found to fit an equation of the form: H = H 0 + b/T; where H is the hardness, T is the temperature, and H 0 and b are constants for a given alloy. An empirical method was devised to estimate the hot hardness of alloys containing more than one solute addition

  11. Kinesio Taping does not decrease swelling in acute, lateral ankle sprain of athletes: a randomised trial

    Directory of Open Access Journals (Sweden)

    Guilherme S Nunes

    2015-01-01

    Full Text Available Question: Does Kinesio Taping reduce swelling in athletes who have suffered an acute, lateral ankle sprain? Design: Randomised controlled trial with concealed allocation, intention-to-treat analysis and blinded assessment. Participants: Thirty-six athletes who participated regularly in one of seven different sports modalities and suffered an acute ankle sprain. Intervention: The experimental group received Kinesio Taping application for 3 days, which was designed to treat swelling. The control group received an inert Kinesio Taping application. Outcome measures: For the comparison between groups, the swelling was measured via volumetry, perimetry, relative volumetry and two analyses of the difference in volume and perimetry between ankles of each participant. Data were collected immediately after the 3 days of intervention and at follow-up, which was 15 days post intervention. Results: At 3 days after intervention, there were no differences between groups for swelling in volumetry (MD –2 ml, 95% CI –28 to 32; perimetry (MD 0.2 cm, 95% CI –0.6 to 1.0; relative volumetry (MD 0.0 cm, 95% CI –0.1 to 0.1; and the other analyses. At day 15 follow-up, there were no significant between-group differences in outcomes. Conclusion: The application of Kinesio Taping, with the aim of stimulating the lymphatic system, is ineffective in decreasing acute swelling after an ankle sprain in athletes. Trial registration: Brazilian Registry of Clinical Trials, RBR-32sctf. [Nunes GS, Vargas VZ, Wageck B, dos Santos Hauphental DP, da Luz CM, de Noronha M (2015 Kinesio Taping does not decrease swelling in acute, lateral ankle sprain of athletes: a randomised trial. Journal of Physiotherapy 61: 28–33

  12. Relationship of chondrocyte apoptosis to matrix degradation and swelling potential of osteoarthritic cartilage.

    Science.gov (United States)

    Chen, Min-Huey; Wang, Jue-Long; Wong, Chi-Yin; Yao, Chung-Chen; Chen, Yi-Jane; Jiang, Ching-Chuan

    2005-04-01

    Softening of cartilage is the initial degenerative step of osteoarthritic cartilage by matrix degradation and corruption of interconnection of the collagen fibrillar network. The purpose of this study was to investigate the correlation of chondrocyte apoptosis, matrix degradation, and the corruption of collagen architecture in the development of severe swelling of osteoarthritic cartilage. Twenty osteoarthritic and 7 normal femoral neck fractured cartilage samples were obtained from patients with knee osteoarthritis and normal patients with femoral neck fracture at the time of total hip joint replacement surgery. Apoptosis was verified by TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick end-labeling) staining and structural changes were observed under phase-contrast microscopy. Matrix degradation was evaluated by histochemical analysis of proteoglycans. Swelling tests were performed by immersing the cartilage slices in hypotonic solution. The results of ultrastructural study of collagen architecture of osteoarthritic cartilage performed by scanning electron microscopy before and after swelling were compared. Matrix degradation was most prominent in the middle zone of osteoarthritic cartilage. The percentage of chondrocytes in osteoarthritic cartilage showing apoptosis ranged from 15 to 20% (average, 18%; standard deviation (SD) = 3.2%) and was correlated with the extent of structural changes and matrix degradation. The swelling strain of the osteoarthritic cartilage varied from 120 to 200% (average, 160%; SD = 40%) depending on the degree of matrix degradation and structural changes. The loss of interconnectivity of collagen fibrillar architecture was correlated with the increased swelling potential of osteoarthritic cartilage. This study demonstrated that chondrocyte apoptosis was correlated with matrix degradation and the corruption of fibrillar architecture and that the extent of these manifestations correlated with the

  13. Effect of fungal decay on the hygroscopic thickness swelling rate of lignocellulosic filler-polyolefin biocomposites

    Science.gov (United States)

    Kord, B.; Hosseinihashemi, S. Kh.

    2014-01-01

    The influence of fungal decay on the hygroscopic thickness swelling rate of lignocellulosic filler-polyolefin biocomposites has been investigated. Composites based on polypropylene (PP), bagasse fiber (BF), and a coupling agent (PP-g-MA) were made by melt compounding and injection molding. The weigt ratio of BF to PP was controlled at 60/40 for all blends. The amount of coupling agent was fixed at 2% for all formulations. The samples obtained were exposed to the action of brown-rot (Coniophora puteana) and white-rot (Trametes versicolor) fungi for 8, 12, and 16 weeks according to the Kolle-flask method. The thickness swelling of the samples was evaluated by immersing them in water at room temperature for several weeks. The morphology of the composites was characterized using the scanning electron microscopy (SEM). The results indicated that the fungal decay had an adverse affect on the dimensional stability of BF/PP composites due to an increase in the thickness swelling rate. The thickness swelling of white-rotted samples was higher than that of brown-rotted ones and control samples. Also, the thickness swelling of BF/PP composites increased with increasing time of fungal decay. In addition, after 16 weeks of exposure to white-rot fungi, the composites exhibited a higher parameter of swelling rate K SR than control samples. The K SR of the composites was influenced both by the type of rooting and the exposure time. Furthermore, the SEM micrographs showed that the extent of degradation increased with growing exposure time to fungi.

  14. A structural model for the in vivo human cornea including collagen-swelling interaction.

    Science.gov (United States)

    Cheng, Xi; Petsche, Steven J; Pinsky, Peter M

    2015-08-06

    A structural model of the in vivo cornea, which accounts for tissue swelling behaviour, for the three-dimensional organization of stromal fibres and for collagen-swelling interaction, is proposed. Modelled as a binary electrolyte gel in thermodynamic equilibrium, the stromal electrostatic free energy is based on the mean-field approximation. To account for active endothelial ionic transport in the in vivo cornea, which modulates osmotic pressure and hydration, stromal mobile ions are shown to satisfy a modified Boltzmann distribution. The elasticity of the stromal collagen network is modelled based on three-dimensional collagen orientation probability distributions for every point in the stroma obtained by synthesizing X-ray diffraction data for azimuthal angle distributions and second harmonic-generated image processing for inclination angle distributions. The model is implemented in a finite-element framework and employed to predict free and confined swelling of stroma in an ionic bath. For the in vivo cornea, the model is used to predict corneal swelling due to increasing intraocular pressure (IOP) and is adapted to model swelling in Fuchs' corneal dystrophy. The biomechanical response of the in vivo cornea to a typical LASIK surgery for myopia is analysed, including tissue fluid pressure and swelling responses. The model provides a new interpretation of the corneal active hydration control (pump-leak) mechanism based on osmotic pressure modulation. The results also illustrate the structural necessity of fibre inclination in stabilizing the corneal refractive surface with respect to changes in tissue hydration and IOP. © 2015 The Author(s).

  15. Assessment of shrinkage-swelling influences in coal seams using rank-dependent physical coal properties

    Energy Technology Data Exchange (ETDEWEB)

    Balan, Huseyin Onur [Middle East Technical University, Ankara (Turkey); Gumrah, Fevzi [Middle East Technical University, Ankara (Turkey)]|[Alberta Research Council, Edmonton (Canada)

    2009-01-07

    Characterization of coal reservoirs and determination of in-situ physical coal properties related to transport mechanism are complicated due to having lack of standard procedures in the literature. By considering these difficulties, a new approach has been developed proposing the usage of relationships between coal rank and physical coal properties. In this study, effects of shrinkage and swelling (SS) on total methane recovery at CO{sub 2} breakthrough (TMRB), which includes ten-year primary methane recovery and succeeding enhanced coalbed methane (ECBM) recovery up to CO{sub 2} breakthrough, and CO{sub 2} sequestration have been investigated by using rank-dependent coal properties. In addition to coal rank, different coal reservoir types, molar compositions of injected fluid, and parameters within the extended Palmer and Mansoori (P and M) permeability model were considered. As a result of this study, shrinkage and swelling lead to an increase in TMRB. Moreover, swelling increased CO{sub 2} breakthrough time and decreased displacement ratio and CO{sub 2} storage for all ranks of coal. Low-rank coals are affected more negatively than high-rank coals by swelling. Furthermore, it was realized that dry coal reservoirs are more influenced by swelling than others and saturated wet coals are more suitable for eliminating the negative effects of CO{sub 2} injection. In addition, it was understood that it is possible to reduce swelling effect of CO{sub 2} on cleat permeability by mixing it with N{sub 2} before injection. However, an economical optimization is required for the selection of proper gas mixture. Finally, it is concluded from sensitivity analysis that elastic modulus is the most important parameter, except the initial cleat porosity, controlling SS in the extended P and M model by highly affecting TMRB. (author)

  16. Novel Biological Hydrogel: Swelling Behaviors Study in Salt Solutions with Different Ionic Valence Number

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2018-01-01

    Full Text Available In this paper, poly γ-glutamic acid/ε-polylysine (γ-PGA/ε-PL hydrogels were successful prepared. The γ-PGA/ε-PL hydrogels could be used to remove Na+, Ca2+, and Cr3+ from aqueous solution and were characterized by scanning electron microscopy. The performance of hydrogels were estimated under different ionic concentration, temperature, and pH. The results showed that the ionic concentration and the pH significantly influenced the swelling capacity of γ-PGA/ε-PL hydrogels. The swelling capacities of γ-PGA/ε-PL hydrogels were decreased with the increase of the ionic concentration. However, the swelling capacity of the γ-PGA/ε-PL hydrogel was increased with the increase of the pH. The swelling kinetics indicated that γ-PGA/ε-PL hydrogels presented a more limited swelling degree in metal ion solutions with higher ionic valence numbers than in ion solutions with lower ionic valence numbers. However, the swelling kinetics of γ-PGA/ε-PL hydrogels showed that they proposed a satisfactory description in NaCl and CaCl2 solutions. The adsorption process was fitted with a pseudo-second-order rate equation model. Moreover, the desorption kinetics of γ-PGA/ε-PL hydrogels showed that they could release most of the adsorption ions. Considering the biocompatibility, biodegradability, and ionic-sensitive properties, we propose that these γ-PGA/ε-PL hydrogels have high potential to be used in environmental protection, medical treatment, and other related fields.

  17. Radiation myelopathy with spinal cord swelling occurring three years after irradiation. A case report

    Energy Technology Data Exchange (ETDEWEB)

    Okuda, Bungo; Okamoto, Kensho; Tagashira, Hiroshi [Ehime Prefectural Central Hospital (Japan)

    2002-02-01

    A 64-year-old woman developed progressive deterioration of sensations, gait, and bladder-bowel functions. The patient had suffered from malignant lymphoma in the neck, and underwent irradiation three years before admission. On admission, she exhibited cervical radiculomyelopathy including spastic tetraplegia, intrinsic muscle atrophy, sensory disturbance in the lower body, and sphincter disturbance. MRI showed diffuse high intensity in the cervical cord on T2-weighted image with Gd-enhancement on T1-weighted image. On serial MRI, swelling of the cervical cord progressed from 36 to 39 months after irradiation. Delayed swelling of the spinal cord can be associated with radiation myelopathy. (author)

  18. Transitory spinal cord swelling in a 6-year-old boy with Guillain-Barre syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Delhaas, T. [Section of Child Neurology, Wilhelmina Children`s Hospital, University Hospital for Children and Youth, Utrecht (Netherlands)]|[Department of Pediatrics, University Hospital Maastricht, P0 Box 5800, 6202 AZ Maastricht (Netherlands); Kamphuis, D.J. [Section of Child Neurology, Wilhelmina Children`s Hospital, University Hospital for Children and Youth, Utrecht (Netherlands); Witkamp, T.D. [Department of Radiology, University Hospital Utrecht, Utrecht (Netherlands)

    1998-07-01

    A 6-year-old boy developed progressive motor weakness and areflexia. The clinical picture, combined with electrophysiological findings, indicated a diagnosis of Guillain-Barre syndrome (GBS). MRI on admission revealed spinal cord swelling and increased signal intensity within the cord. It is concluded that, since a degree of central nervous system involvement can occasionally be part of the spectrum of GBS, swelling of the spinal cord without contrast enhancement does not exclude a diagnosis of GBS. (orig.) With 2 figs., 8 refs.

  19. Radiation myelopathy with spinal cord swelling occurring three years after irradiation. A case report

    International Nuclear Information System (INIS)

    Okuda, Bungo; Okamoto, Kensho; Tagashira, Hiroshi

    2002-01-01

    A 64-year-old woman developed progressive deterioration of sensations, gait, and bladder-bowel functions. The patient had suffered from malignant lymphoma in the neck, and underwent irradiation three years before admission. On admission, she exhibited cervical radiculomyelopathy including spastic tetraplegia, intrinsic muscle atrophy, sensory disturbance in the lower body, and sphincter disturbance. MRI showed diffuse high intensity in the cervical cord on T2-weighted image with Gd-enhancement on T1-weighted image. On serial MRI, swelling of the cervical cord progressed from 36 to 39 months after irradiation. Delayed swelling of the spinal cord can be associated with radiation myelopathy. (author)

  20. Bowing-reactivity trends in EBR-II assuming zero-swelling ducts

    International Nuclear Information System (INIS)

    Meneghetti, D.

    1994-01-01

    Predicted trends of duct-bowing reactivities for the Experimental Breeder Reactor II (EBR-II) are correlated with predicted row-wise duct deflections assuming use of idealized zero-void-swelling subassembly ducts. These assume no irradiation induced swellings of ducts but include estimates of the effects of irradiation-creep relaxation of thermally induced bowing stresses. The results illustrate the manners in which at-power creeps may affect subsequent duct deflections at zero power and thereby the trends of the bowing component of a subsequent power reactivity decrement

  1. Large Plunging Ranula Presenting as Isolated Neck Swelling: Steps in Diagnosis and Surgical Steps in Management.

    Science.gov (United States)

    Nilesh, Kumar; Malik, Neelima A; Patil, Pankaj; Chapi, Mouneshkumar Devendrappa

    2015-06-01

    Ranula is a salivary gland cyst which typically present as localized superficial swelling over the floor of mouth. Complex or plunging ranulas develop when the mucus extravasation extends through or around the mylohyoid muscle, deeper into the neck, and present with neck lump along with or without swelling over floor of mouth. We report a case of large plunging ranula presenting as an isolated large neck mass in a 38-year-old female patient. The steps in diagnosis and surgical steps in management of the pathology are systematically described.

  2. Elastic, permeability and swelling properties of human intervertebral disc tissues: A benchmark for tissue engineering.

    Science.gov (United States)

    Cortes, Daniel H; Jacobs, Nathan T; DeLucca, John F; Elliott, Dawn M

    2014-06-27

    The aim of functional tissue engineering is to repair and replace tissues that have a biomechanical function, i.e., connective orthopaedic tissues. To do this, it is necessary to have accurate benchmarks for the elastic, permeability, and swelling (i.e., biphasic-swelling) properties of native tissues. However, in the case of the intervertebral disc, the biphasic-swelling properties of individual tissues reported in the literature exhibit great variation and even span several orders of magnitude. This variation is probably caused by differences in the testing protocols and the constitutive models used to analyze the data. Therefore, the objective of this study was to measure the human lumbar disc annulus fibrosus (AF), nucleus pulposus (NP), and cartilaginous endplates (CEP) biphasic-swelling properties using a consistent experimental protocol and analyses. The testing protocol was composed of a swelling period followed by multiple confined compression ramps. To analyze the confined compression data, the tissues were modeled using a biphasic-swelling model, which augments the standard biphasic model through the addition of a deformation-dependent osmotic pressure term. This model allows considering the swelling deformations and the contribution of osmotic pressure in the analysis of the experimental data. The swelling stretch was not different between the disc regions (AF: 1.28±0.16; NP: 1.73±0.74; CEP: 1.29±0.26), with a total average of 1.42. The aggregate modulus (Ha) of the extra-fibrillar matrix was higher in the CEP (390kPa) compared to the NP (100kPa) or AF (30kPa). The permeability was very different across tissue regions, with the AF permeability (64 E(-16)m(4)/Ns) higher than the NP and CEP (~5.5 E(-16)m(4)/Ns). Additionally, a normalized time-constant (3000s) for the stress relaxation was similar for all the disc tissues. The properties measured in this study are important as benchmarks for tissue engineering and for modeling the disc's mechanical

  3. Swelling behaviour of Early Jurassic shales when exposed to water vapour

    Science.gov (United States)

    Houben, Maartje; Barnhoorn, Auke; Peach, Colin; Drury, Martyn

    2017-04-01

    The presence of water in mudrocks has a largely negative impact on production of gas, due to the fact that water causes swelling of the rock. Removing the water from the mudrock on the other hand could potentially shrink the rock and increase the matrix permeability. Investigation of the swelling/shrinkage behaviour of the rock during exposure to water vapour is of key importance in designing and optimizing unconventional production strategies. We have used outcrop samples of the Whitby Mudstone and the Posidonia shale [1], potential unconventional sources for gas in North-western Europe, to measure the swelling and shrinkage behaviour. Subsamples, 1 mm cubes, were prepared by the Glass Workshop at Utrecht University using a high precision digitally controlled diamond wafering saw cooled by air. The mm cubes were then exposed to atmospheres with different relative humidities either in an Environmental Scanning Electron Microscope (ESEM) or in a 3D dilatometer. So that the sample responses to exposure of water vapour could be measured. Parallel to the bedding we found a swelling strain between 0.5 and 1.5 %, perpendicular to the bedding though swelling strain varied between 1 and 3.5%. Volumetric swelling strain varied between 1 and 2% at a maximum relative humidity of 95%. Volumetric swelling strains measured in the Early Toarcian Shales are similar to the ones found in coal [2], where the results suggest that it might be possible to increase permeability in the reservoir by decreasing the in-situ water activity due to shrinkage of the matrix. [1] M.E. Houben, A. Barnhoorn, L. Wasch, J. Trabucho-Alexandre, C. J. Peach, M.R. Drury (2016). Microstructures of Early Jurassic (Toarcian) shales of Northern Europe, International Journal of Coal Geology, 165, 76-89. [2] Jinfeng Liu, Colin J. Peach, Christopher J. Spiers (2016). Anisotropic swelling behaviour of coal matrix cubes exposed to water vapour: Effects of relative humidity and sample size, International Journal of

  4. Theoretical analysis of swelling characteristics of cylindrical uranium dioxide fuel pins with a niobium - 1-percent-zirconium clad

    Science.gov (United States)

    Saltsman, J. F.

    1973-01-01

    The relations between clad creep strain and fuel volume swelling are shown for cylindrical UO2 fuel pins with a Nb-1Zr clad. These relations were obtained by using the computer code CYGRO-2. These clad-strain - fuel-volume-swelling relations may be used with any fuel-volume-swelling model, provided the fuel volume swelling is isotropic and independent of the clad restraints. The effects of clad temperature (over a range from 118 to 1642 K (2010 to 2960 R)), pin diameter, clad thickness and central hole size in the fuel have been investigated. In all calculations the irradiation time was 500 hours. The burnup rate was varied.

  5. Constrained swelling of polymer networks: characterization of vapor-deposited cross-linked polymer thin films

    Czech Academy of Sciences Publication Activity Database

    Dušek, Karel; Choukourov, A.; Dušková-Smrčková, Miroslava; Biederman, H.

    2014-01-01

    Roč. 47, č. 13 (2014), s. 4417-4427 ISSN 0024-9297 R&D Projects: GA ČR GAP101/12/1306 Institutional support: RVO:61389013 Keywords : swelling * cross-linked polymer * elasticity Subject RIV: CD - Macromolecular Chemistry Impact factor: 5.800, year: 2014

  6. Biopolymer gel swelling analysed with scaling laws and Flory-Rehner theory

    NARCIS (Netherlands)

    Sman, van der R.G.M.

    2015-01-01

    The swelling of biopolymer gels is analysed with scaling laws from polymer physics, as an alternative for the classical Flory-Rehner theory. With these scaling laws, holding for polymer concentrations in the semi-dilute regime, experimental data on deswelling of gels can be collapsed to a single

  7. The role of bulk recombination in the theory of void swelling

    International Nuclear Information System (INIS)

    Hayns, M.R.

    1978-01-01

    Bulk point defect recombination in the rate theory of void swelling is considered in two ways. First the importance of recombination in the overall void swelling problem is assessed in the light of current experimental data on the temperature dependence of the sink densities. It is found that the assumption that recombination is negligible at and above the peak swelling temperature is not generally true, and is often the reverse of this. Secondly recombination is included in the sink strengths themselves very much in the same spirit as the interactive correction terms have been for losses to other sinks. An approximate numerical procedure has been used to evaluate the resulting coupled sink strengths. Using only the corrections to the cavity sink strengths we have shown that these new terms are only significant at temperatures well in excess of the swelling peak in ST316 under HVEM irradiations and that they need not be included as a general rule in rate theory calculations. Comparisons with a mathematical, perturbation theory treatment of the same problem and with full numerical cellular model results confirm the usefulness of the prsent method. (author)

  8. Propionate induces cell swelling and K+ accumulation in shark rectal gland

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, G.M.; Ziyadeh, F.N.; Mills, J.W.; Booz, G.W.; Kleinzeller, A. (Mount Desert Island Biological Laboratory, Salsbury Cove, ME (USA))

    1989-08-01

    Small organic anions have been reported to induce cell solute accumulation and swelling. To investigate the mechanism of swelling, we utilized preparations of rectal gland cells from Squalus acanthias incubated in medium containing propionate. Propionate causes cells to swell by diffusing across membranes in its nonionic form, acidifying cell contents, and activating the Na+-H+ antiporter. The Na+-H+ exchange process tends to correct intracellular pH (pHi), and thus it maintains a favorable gradient for propionic acid diffusion and allows propionate to accumulate. Activation of the Na+-H+ antiport also facilitates Na+ entry into the cell and Nai accumulation. At the same time Na+-K+-ATPase activity, unaffected by propionate, replaces Nai with Ki, whereas the K+ leak rate, decreased by propionate, allows Ki to accumulate. As judged by {sup 86}Rb+ efflux, the reduction in K+ leak was not due to propionate-induced cell acidification or reduction in Cli concentration. Despite inducing cell swelling, propionate did not disrupt cell structural elements and F actin distribution along cell membranes.

  9. Throat ache ans swelling of the neck: first symptoms of Lemierre's syndrome

    NARCIS (Netherlands)

    de Lange, J.; Ybema, A; Baas, E. M.

    2014-01-01

    Lemierre's syndrome, a thrombophlebitis of the internal jugular vein, is a rare disorder, usually caused by the microorganism Fusobacterium necrophorum. Throat ache and swelling of the neck are often the first symptoms. Without adequate treatment, Lemierre's syndrome may result in thrombosis of the

  10. Bilateral breast swelling secondary to superior vena cava obstruction and subclavian vein thrombosis

    Directory of Open Access Journals (Sweden)

    Ariadne Mayumi Yamada

    2013-07-01

    Full Text Available Superior vena cava syndrome is defined by a set of signs and symptoms secondary to superior vena cava obstruction caused principally by malignant diseases. The present report describes the case of an unusual clinical manifestation of this syndrome with bilateral breast swelling, and emphasizes the relevance of knowledge on mammographic signs of systemic diseases.

  11. Ocean swell variability along the northern coast of the Gulf of Guinea ...

    African Journals Online (AJOL)

    This study analyses a 4.5 year (September 2009–March 2014) time-series of remotely-sensed data of altimeter significant wave heights to describe the temporal and spatial variability of ocean swells along the northern coast of the Gulf of Guinea. The NOAA WAVEWATCH III (NWW3) wave model data were used with ...

  12. Micromechanical Characterization of Hydrogels Undergoing Swelling and Dissolution at Alkaline pH

    Directory of Open Access Journals (Sweden)

    Wei Hu

    2017-11-01

    Full Text Available The swelling of polyelectrolyte hydrogels usually depends on the pH, and if the pH is high enough degradation can occur. A microindentation device was developed to dynamically test these processes in whey protein isolate hydrogels at alkaline pH 7–14. At low alkaline pH the shear modulus decreases during swelling, consistent with rubber elasticity theory, yet when chemical degradation occurs at pH ≥ 11.5 the modulus decreases quickly and extensively. The apparent modulus was constant with the indentation depth when swelling predominates, but gradients were observed when fast chemical degradation occurs at 0.05–0.1 M NaOH. In addition, these profiles were constant with time when dissolution rates are also constant, the first evidence that a swollen layer with steady state mechanical properties is achieved despite extensive dissolution. At >0.5 M NaOH, we provide mechanical evidence showing that most interactions inside the gels are destroyed, gels were very weak and hardly swell, yet they still dissolve very slowly. Microindentation can provide complementary valuable information to study the degradation of hydrogels.

  13. Effect of a foot pump device on lower leg swelling in physically ...

    African Journals Online (AJOL)

    The aim of the study was to examine the effect of using a foot pump device (FPD) on orthostatic lower leg swelling in physically inactive office workers. Thirty-four physically inactive office workers (age: 41.6 ± 8.9 years, 26 females, 8 males) volunteered for the study. They participated in two exercise days (day 1 and 2), ...

  14. Upper lip swelling caused by a large dentigerous cyst with mesiodens.

    Science.gov (United States)

    Khan, M H; Alam, M T; Haque, S; Khan, S H; Fatema, C N; Tahsin, T; Choudhury, A R

    2008-07-01

    Swelling of upper lip can results from various diseases such as salivary tumors, infections and inflammatory diseases and cyst, typically involving unerrupted teeth, are sometimes associated with supernumerary teeth in the maxillary anterior incisor region called the mesiodens. Mesiodens with dentigerous cyst is actually a rare case in the world and of course in Bangladesh. The overall prevalence of this type of cyst is only 0.15-1.9% of the total population. Recently we have experienced this kind of case like dentigerous cyst with mesiodens in the department of dentistry, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM) Hospital. The patient was 24 years old male young complaining of slow growing painless swelling on the upper lip region for the last several years. Clinical examination revealed a soft intra oral swelling in the labial surface of maxillary incisor region and there was also extra orally upper lip swelling. Radiographic examination demonstrated a large radiolucent area with a mesiodens extending to the root of both lateral incisors. The patient was treated surgically by enucleation of total cysts and surgical extraction of mesiodens under local anesthesia.

  15. Swelling behaviour of isora/natural rubber composites in oils used in ...

    Indian Academy of Sciences (India)

    Unknown

    Swelling behaviour of isora/natural rubber composites in oils used in ... 1. Introduction. Natural fibre reinforced composites is an emerging area in polymer technology. Strong environmental regulations and increased interest in the proper utilization of ... palm, banana, jute, pineapple, bamboo etc have been studied.

  16. Swelling of austenitic iron-nickelchromium ternary alloys during fast neutron irradiation

    International Nuclear Information System (INIS)

    Garner, F.A.; Brager, H.R.

    1984-01-01

    Swelling data are now available for 15 iron-nickel-chromium ternary alloys irradiated to exposures as high as 110 displacements per atom (dpa) in Experimental Breeder Reactor-II (EBR-II) between 400 and 650 0 C. These data confirm trends observed at lower exposure levels and extend the generality of earlier conclusions to cover a broader range of composition and temperature. It appears that all austenitic iron-nickel-chromium ternary alloys eventually approach an intrinsic swelling rate of about1%/dpa over a range of temperature even wider than studied in this experiment. The duration of the transient regime that precedes the attainment of this rate is quite sensitive to nickel and chromium content, however. At nickel and chromium levels typical of 300 series steels, swelling does not saturate at engineering-relevant levels. However, there appears to be a tendency toward saturation that increases with declining temperature, increasing nickel and decreasing chromium levels. Comparisons of these results are made with those of similar studies conducted with charged particles. Conclusions are then drawn concerning the validity of charged particle simulation studies to determine the compositional and temperature dependence of swelling

  17. Modeling of bubble growth in complex fluids. Application to radiolytic swelling of nuclear bituminized waste products

    International Nuclear Information System (INIS)

    Marchal, Antoine

    2015-01-01

    The aim of this PhD thesis is to predict the swelling of bitumen barrels in which radioactive salts are mixed. The bitumen exposed to radioactivity undergoes a chemical reaction: the radiolysis. This implies a generation of dihydrogen. The created is solubilized until the concentration reaches a limit value which is called saturation. Over this limit nucleation of bubbles is observed. Then they will grow thank to the contribution of the gas generated by radiolysis and they will be submitted to Archimede's principle so that they will rise in the fluid. The swelling is the result of the competition between generation and evacuation of gas. A model has been built to describe the evolution of a bubble population. Because of it is not possible to solve it analytically, a numerical program was developed. The results show that an increase of the fluid viscosity, the gas generation or the container height lead to an increase of the swelling and that an increase of the diffusion coefficient contributes to a decrease of the swelling. In the particular case of a yield stress fluid, the behavior of the bubble population is modified and the evacuation of gas is done with several shots, at the opposite of the case of a Newtonian fluid for which a stationary evacuation is reached. (author)

  18. HYPOOSMOTIC SPERM SWELLING TEST DOES NOT ASSESS FERTILIZING-CAPACITY OF HUMAN SPERMATOZOA

    NARCIS (Netherlands)

    JAGER, S; KREMER, J; WIJCHMAN, J

    1991-01-01

    The hypo-osmotic sperm swelling (HOSS) test was performed on semen samples of five normospermic men from couples with prolonged infertility. Previously, the men had negative results of the zona-free hamster oocyte (ZFHO) test on two different ejaculates and the wives subsequently had become pregnant

  19. Swelling behaviour of isora/natural rubber composites in oils used

    Indian Academy of Sciences (India)

    Natural rubber/isora fibre composites were cured at various temperatures. The solvent swelling characteristics of natural rubber composites containing both untreated and alkali treated fibres were investigated in aromatic and aliphatic solvents like toluene, and -hexane. The diffusion experiments were conducted by the ...

  20. Sea and swell along west coast of India: Study based on measured data

    Digital Repository Service at National Institute of Oceanography (India)

    SanilKumar, V.; AshokKumar, K.; Pednekar, P.; Gowthaman, R.

    Separation of sea and swell from the measured data is important for studying the wind wave dynamics and in the design of coastal and offshore structures. The wave data collected using Datawell directional waverider buoy at a deep-water location...

  1. Second toe swelling: Nora's lesion or glomus tumour, case report and literature review.

    LENUS (Irish Health Repository)

    Mohammad, A

    2012-09-01

    We report a rare case of bizarre parosteal osteochondromatous proliferation (BPOP, Nora\\'s lesion) of the right second toe in a 60-year-old man who presented with painful, bluish and bulbous swelling of the right second toe without any break in the skin.

  2. Thermodynamic model for swelling of unconfined coal due to adsorption of mixed gases

    NARCIS (Netherlands)

    Liu, J.; Peach, C.J.; Zhou, Hongwei; Spiers, C.J.

    2015-01-01

    Permeability evolution in coal seams during CO2-Enhanced Coalbed Methane (ECBM) production is strongly influenced by swelling/shrinkage effects related to sorption and desorption of both CO2 and CH4. Other gases, such as N2, have also been proposed for injection in ECBM operations. In addition,

  3. Poststroke hand swelling and oedema : prevalence and relationship with impairment and disability

    NARCIS (Netherlands)

    Boomkamp-Koppen, HGM; Visser-Meily, JMA; Post, MWM; Prevo, AJH

    Objective: To examine the prevalence of swelling and oedema of the hand in stroke patients and relationships with impairments and disability. Design: Cross-sectional. Setting: Stroke unit at Rehabilitation Centre De Hoogstraat, the Netherlands. Subjects: Eighty-eight adult stroke patients who were

  4. Swelling behaviour of isora/natural rubber composites in oils used in ...

    Indian Academy of Sciences (India)

    Unknown

    incompatibility of the fibres and poor resistance to moisture often reduce the potential of natural fibres. ... portant as a method of analysing their service performance when in contact with solvents. Swelling of rubber vul ..... Jost W 1952 Diffusion in solids, liquids and gases (New York: Academic Press). Khalil H P, Ismail H and ...

  5. Water absorption, retention and the swelling characteristics of cassava starch grafted with polyacrylic acid

    NARCIS (Netherlands)

    Witono, J. R.; Noordergraaf, Inge; Heeres, H. J.; Janssen, L. P. B. M.; Heeres, Hero

    2014-01-01

    An important application of starch grafted with copolymers from unsaturated organic acids is the use as water absorbent. Although much research has been published in recent years, the kinetics of water absorption and the swelling behavior of starch based superabsorbents are relatively unexplored.

  6. A case report of chronic frontal bone osteitis presenting with recurrent unilateral lid swelling

    Directory of Open Access Journals (Sweden)

    A Tandon

    2010-12-01

    Full Text Available Despite the advances in modern antimicrobial treatment, paranasal sinus disease remains relatively common. A case of chronic inflammatory frontal sinus disease presented with unilateral recurrent eyelid swelling. Clinical features and management in conjunction with ENT are discussed. An extensive literature search has shown only one other similar case reported in Russian language whose management details however are not available.

  7. A brief review of cavity swelling and hardening in irradiated copper and copper alloys

    International Nuclear Information System (INIS)

    Zinkle, S.J.

    1990-01-01

    The literature on radiation-induced swelling and hardening in copper and its alloy is reviewed. Void formation does not occur during irradiation of copper unless suitable impurity atoms such as oxygen or helium are present. Void formation occurs for neutron irradiation temperatures of 180 to 550 degree C, with peak swelling occurring at ∼320 degree C for irradiation at a damage rate of 2 x 10 -7 dpa/s. The post-transient swelling rate has been measured to be ∼0.5%/dpa at temperatures near 400 degree C. Dispersion-strengthened copper has been found to be very resistant to void swelling due to the high sink density associated with the dispersion-stabilized dislocation structure. Irradiation of copper at temperatures below 400 degree C generally causes an increase in strength due to the formation of defect clusters which inhibit dislocation motion. The radiation hardening can be adequately described by Seeger's dispersed barrier model, with a barrier strength for small defect clusters of α ∼ 0.2. The radiation hardening apparently saturates for fluences greater than ∼10 24 n/m 2 during irradiation at room temperature due to a saturation of the defect cluster density. Grain boundaries can modify the hardening behavior by blocking the transmission of dislocation slip bands, leading to a radiation- modified Hall-Petch relation between yield strength and grain size. Radiation-enhanced recrystallization can lead to softening of cold-worked copper alloys at temperatures above 300 degree C

  8. Structure and swelling behaviour of hydrophilic epoxy networks investigated by SANS

    Czech Academy of Sciences Publication Activity Database

    Krakovský, I.; Pleštil, Josef; Almásy, L.

    2006-01-01

    Roč. 47, č. 1 (2006), s. 218-226 ISSN 0032-3861 R&D Projects: GA ČR GA203/03/0600 Institutional research plan: CEZ:AV0Z40500505 Keywords : epoxy network * swelling * small - angle neutron scattering Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.773, year: 2006

  9. Full length cluster level swell data at pressures from 2 to 40 bar

    International Nuclear Information System (INIS)

    Pearson, K.G.

    1987-11-01

    This paper gives results of level swell experiments at pressures up to 40 bar, performed at Winfrith in 1981 as described elsewhere. The results have been used by a number of workers to develop voidage correlations and to assess safety codes. The experiment and experimental rig used are described. The results are tabulated. (author)

  10. On grain-size-dependent void swelling in pure copper irradiated with fission neutrons

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Eldrup, Morten Mostgaard; Zinkle, S.J.

    2002-01-01

    The effect of grain size on void swelling has its origin in the intrinsic property of grain boundaries as neutral and unsaturable sinks for both vacancies and self-interstitial atoms. The phenomenon had already been investigated in the 1970s and it was demonstrated that the grain-size-dependent v...

  11. Propionate induces cell swelling and K+ accumulation in shark rectal gland

    International Nuclear Information System (INIS)

    Feldman, G.M.; Ziyadeh, F.N.; Mills, J.W.; Booz, G.W.; Kleinzeller, A.

    1989-01-01

    Small organic anions have been reported to induce cell solute accumulation and swelling. To investigate the mechanism of swelling, we utilized preparations of rectal gland cells from Squalus acanthias incubated in medium containing propionate. Propionate causes cells to swell by diffusing across membranes in its nonionic form, acidifying cell contents, and activating the Na+-H+ antiporter. The Na+-H+ exchange process tends to correct intracellular pH (pHi), and thus it maintains a favorable gradient for propionic acid diffusion and allows propionate to accumulate. Activation of the Na+-H+ antiport also facilitates Na+ entry into the cell and Nai accumulation. At the same time Na+-K+-ATPase activity, unaffected by propionate, replaces Nai with Ki, whereas the K+ leak rate, decreased by propionate, allows Ki to accumulate. As judged by 86 Rb+ efflux, the reduction in K+ leak was not due to propionate-induced cell acidification or reduction in Cli concentration. Despite inducing cell swelling, propionate did not disrupt cell structural elements and F actin distribution along cell membranes

  12. Propagation of Atlantic Ocean swells in the north Indian Ocean: A case study

    Digital Repository Service at National Institute of Oceanography (India)

    Samiksha, S.V.; Vethamony, P.; Aboobacker, V.M.; Rashmi, R.

    An analysis of altimeter significant wave height data of May 2007 revealed the occurrence of an extreme weather event off southern tip of South Africa in the Atlantic Ocean, and generation of a series of very high swells at 40 degrees S...

  13. Swelling, mechanical properties, and microstructure of Type 316 stainless steel at fusion reactor damage levels

    International Nuclear Information System (INIS)

    Horak, J.A.; Bloom, E.E.; Grossbeck, M.L.; Maziasz, P.J.; Stiegler, J.O.; Wiffen, F.W.

    1979-01-01

    Alloys such as AISI 316 stainless steel exhibit more swelling and larger decreases in ductility when irradiated to produce fusion reactor He and dpa levels than at fast reactor He and dpa levels. For T approx. 0 C to ensure adequate ductility for long-term service

  14. Reliability and validity of measurements of facial swelling with a stereophotogrammetry optical three-dimensional scanner

    NARCIS (Netherlands)

    van der Meer, Wicher J.; Dijkstra, Pieter U.; Visser, Anita; Vissink, Arjan; Ren, Yijin

    2014-01-01

    Volume changes in facial morphology can be assessed using the 3dMD DSP400 stereo-optical 3-dimensional scanner, which uses visible light and has a short scanning time. Its reliability and validity have not to our knowledge been investigated for the assessment of facial swelling. Our aim therefore

  15. A young woman with a supraclavicular swelling; some diagnostic aspects of thyroid carcinoma

    International Nuclear Information System (INIS)

    Logmans, S.C.; Jobsis, A.C.; Schoot, J.V. van der; Schipper, M.E.I.; Kromhout, J.G.

    1983-01-01

    The case is reported of a woman aged 24 years who presented a supraclavicular swelling caused by a lymph-node metastasis of an adenopapillary carcinoma. The primary tumour was found in the thyroid in which palpation and scintigraphy failed to reveal any abnormalities. The diagnosis and the diagnostic value of scintigraphic and immunohistological examination are considered. (Auth.)

  16. Modeling and Stress Analysis of Doubly-Fed Induction Generator during Grid Voltage Swell

    DEFF Research Database (Denmark)

    Zhou, Dao; Song, Yipeng; Blaabjerg, Frede

    2016-01-01

    The Doubly-Fed Induction Generator (DFIG) based wind turbine system is presently dominant in the wind turbine market. Due to heavy load switch-off and faults in the power grid, voltage swells may occur and this phenomenon is currently given sufficient insights. This paper starts to describe the D...

  17. Swelling and tribological properties of melt-mixed fluoroelastomer/nitrile rubber blends under crude oil

    Science.gov (United States)

    Tagelsir, Yasin; Li, San-Xi; Lv, Xiaoren; Wang, Shijie; Wang, Song; Osman, Zeinab

    2018-01-01

    The melt-mixed fluoroelastomer (FKM)/ nitrile rubber (NBR) blends of (90/10, 80/20, 70/30, 60/40 and 50/50) ratios with same hardness were prepared, and their swelling and tribological properties under crude oil were investigated for the purpose of developing high performance cost-effective elastomers meeting requirement of oil extraction progressive cavity pump stator. Differential scanning calorimetry confirmed compatible blend system for all blends. Field emission scanning electron microscopy (FE-SEM) showed co-continuous morphology of 200–400 nm phase size for all blends, expect FKM/NBR (90/10) which exhibited partially continuous phase morphology of 100–250 nm phase size. The results of swelling and linear wear tests under crude oil indicated that swelling percentage, coefficient of friction and specific wear rate of FKM/NBR blends were much better than NBR, with FKM/NBR (90/10 and 80/20) showing swelling percentage and specific wear rate very close to FKM. Attenuated total reflectance-Fourier transform infrared spectroscopy disclosed that fracture of macromolecular chains was the main mechanochemical effect of unswollen and swollen worn surfaces, in addition to oxygenated degradation detected with increasing NBR ratio in the blends. The fracture of macromolecular chains resulted in slight fatigue wear mechanism, which was also confirmed by FE-SEM of the worn surfaces.

  18. Mechanical modeling of creep, swelling and damage under irradiation for polycrystalline metals

    International Nuclear Information System (INIS)

    Murakami, S.; Mizuno, M.; Okamoto, T.

    1991-01-01

    A constitutive equation of creep, swelling and damage under irradiation for polycrystalline metals applicable to structural analyses in multiaxial state of stress is developed. After reviewing microscopic mechanisms of irradiation creep and swelling, the relevant theories proposed so far from the view point of metallurgical physics and their applicability are discussed first. Then a constitutive model is developed by assuming that creep under irradiation can be decomposed into irradiation-affected thermal creep and irradiation-induced creep. By taking account of the Stress-Induced Preferential Absorption (SIPA) mechanism, the irradiation-induced creep is represented by an isotropic tensor function of order one and zero with respect to stress, which is, at the same time, the function of neutron flux and neutron fluence. The volumetric part of the irradiation-induced creep is identified with swelling. The irradiation-affected thermal creep is described by modifying Kachanov-Rabotnov theory for stress-controlled creep and creep damage by incorporating the effect of irradiation. Finally irradiation creep and swelling of 20% cold-worked type 316 stainless steel at elevated temperature are predicted by the proposed constitutive equations, and the numerical results are compared with the corresponding experimental results. (orig.)

  19. Simulating the swelling and deformation behaviour in soft tissues using a convective thermal analogy

    Directory of Open Access Journals (Sweden)

    Herzog Walter

    2002-12-01

    Full Text Available Abstract Background It is generally accepted that cartilage adaptation and degeneration are mechanically mediated. Investigating the swelling behaviour of cartilage is important because the stress and strain state of cartilage is associated with the swelling and deformation behaviour. It is well accepted that the swelling of soft tissues is associated with mechanical, chemical, and electrical events. Method The purpose of the present study was to implement the triphasic theory into a commercial finite element tool (ABAQUS to solve practical problems in cartilage mechanics. Because of the mathematical identity between thermal and mass diffusion processes, the triphasic model was transferred into a convective thermal diffusion process in the commercial finite element software. The problem was solved using an iterative procedure. Results The proposed approach was validated using the one-dimensional numerical solutions and the experimental results of confined compression of articular cartilage described in the literature. The time-history of the force response of a cartilage specimen in confined compression, which was subjected to swelling caused by a sudden change of saline concentration, was predicted using the proposed approach and compared with the published experimental data. Conclusion The advantage of the proposed thermal analogy technique over previous studies is that it accounts for the convective diffusion of ion concentrations and the Donnan osmotic pressure in the interstitial fluid.

  20. Recent studies on wind seas and swells in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; Rashmi, R.; Samiksha, S.V.; Aboobacker, V.M.

    Winds and waves measured at a few locations along the west coast of India were analysed to study the wave characteristics in the deep as well as near shore regions during different seasons. The potential generation of swells observed in the Arabian...

  1. Simulating the swelling and deformation behaviour in soft tissues using a convective thermal analogy.

    Science.gov (United States)

    Wu, John Z; Herzog, Walter

    2002-12-19

    It is generally accepted that cartilage adaptation and degeneration are mechanically mediated. Investigating the swelling behaviour of cartilage is important because the stress and strain state of cartilage is associated with the swelling and deformation behaviour. It is well accepted that the swelling of soft tissues is associated with mechanical, chemical, and electrical events. The purpose of the present study was to implement the triphasic theory into a commercial finite element tool (ABAQUS) to solve practical problems in cartilage mechanics. Because of the mathematical identity between thermal and mass diffusion processes, the triphasic model was transferred into a convective thermal diffusion process in the commercial finite element software. The problem was solved using an iterative procedure. The proposed approach was validated using the one-dimensional numerical solutions and the experimental results of confined compression of articular cartilage described in the literature. The time-history of the force response of a cartilage specimen in confined compression, which was subjected to swelling caused by a sudden change of saline concentration, was predicted using the proposed approach and compared with the published experimental data. The advantage of the proposed thermal analogy technique over previous studies is that it accounts for the convective diffusion of ion concentrations and the Donnan osmotic pressure in the interstitial fluid.

  2. Statistical moments in modelling of swelling, erosion and drug release of hydrophilic matrix-tablets.

    Science.gov (United States)

    Barmpalexis, P; Kachrimanis, K; Malamataris, S

    2018-04-05

    Statistical moments were evaluated as suitable parameters for describing swelling and erosion processes (along with drug release) in hydrophilic controlled release matrix tablets. The effect of four independent formulation variables, corresponding to the quantity of four polymeric matrix excipients (namely polyethylene glycol, povidone, and two grades of hydroxyl-propylmethyl cellulose) on statistical moments describing swelling (mean swelling time, MST), erosion (mean erosion time, MET) and drug-release (mean dissolution time, MDT) was evaluated with the aid of multi-linear regression (MLR) and artificial neural networks (ANNs) based on a central composite experimental design. Results were compared to conventional model fitting, where the rate of water uptake during swelling (a), the maximum % water uptake (S max ), the time at which S max is achieved (t max ), the constant of apparent matrix-tablet erosion rate (k e ) and the release exponent (n) from Korsmeyer-Peppas drug-release equation were used as model parameters. Fitting to an external validation test set revealed superior prediction efficacy for statistical moments compared to conventional model fitting, while the combination of statistical moments with ANNs presented the most efficient approach (R 2 and RMSEp values of 0.922, 0.833, 0.987 and 0.443, 0.691, 0.173 for MST, MET, and MDT, respectively). Copyright © 2018 Elsevier B.V. All rights reserved.

  3. ON THE THEORY OF DIFFUSION AND SWELLING IN FINITELY DEFORMING ELASTOMERS

    OpenAIRE

    Gary J., Templet; Steigmann:, David J.

    2013-01-01

    International audience; The role of a relaxed local intermediate configuration associated with free swelling is examined in the context of diffusion of a liquid in an isotropic elastomer. It is found that this configuration is energetically optimal if the free-energy function of the polymer-liquid gel is polyconvex. Further aspects of the general theory of diffusion in elastomers are also discussed.

  4. Flakeboard thickness swelling. Part I, Stress relaxation in a flakeboard mat

    Science.gov (United States)

    R. L. Geimer; J. H. Kwon; J. Bolton

    1998-01-01

    The steam injection schedule best suited for dimensionally stabilizing a flake mat is one in which steam treatment is initiated before the press is closed and is continued at least until the mat attains target thickness. Experiments showed that resinless mats treated with 20 sec of steam at 600 kPa had maximum thickness swelling of 205% compared to 350% for resinless...

  5. Unvulcanized elastomeric waterproofing materials for construction application

    Directory of Open Access Journals (Sweden)

    O. V. Karmanova

    2016-01-01

    Full Text Available In the construction was widespread elastomer profiles, which have the ability to swell in water. Such products should have a high capacity for swelling, elasticity, resistance to weathering. At the present time for these purposes are used materials, mostly of foreign origin. With the increasing pace of construction in Russia the problem of replacement of imported materials is particularly relevant. The work was dedicated to the creation of water-swellable elastomer materials using bentonite powders and study of their properties. Сomparative testing of imported and domestic hydrophilic sealants were held. Rationale and choice of components for the cords of bentonite was conducted. Polymer base is saturated ethylene-propylene rubber. Bentonite from different manufacturers used to increase the swelling of the samples. Filler added in an amount of 50–100 phr. The elastomeric compositions were prepared using laboratory roller at a temperature of 60 ± 5° C. Profiling was performed on a syringe-machine at a temperature of 120° C. Extrusion indicator of the mixtures were evaluated on a 10-point scale (German-Russian system. It is found that high swelling products provided using field Azerbaijan bentonite. It is noted that the dosage of bentonite than 150 w.p. deteriorates technological properties of bentonite cords. It has been shown that activation of the bentonite and sodium carbonate chloride can significantly improve product swelling, wherein the bentonite content of the composition was 150–200 w.p.

  6. Influence of kinesiologic tape on postoperative swelling, pain and trismus after zygomatico-orbital fractures.

    Science.gov (United States)

    Ristow, Oliver; Pautke, Christoph; Victoria Kehl; Koerdt, Steffen; Schwärzler, Katharina; Hahnefeld, Lilian; Hohlweg-Majert, Bettina

    2014-07-01

    Surgical treatment of zygomatico-orbital (ZO) fractures is a common procedure in maxillofacial surgery. Often accompanied by pain, trismus and swelling, postoperative morbidity is a major disadvantage, affecting patients' quality of life. The appliance of kinesiologic tape (KT) improves the blood and lymph flow, removing congestions of lymphatic fluid and haemorrhages. The aim of this study was to find out if the application of kinesiologic tape prevents or improves swelling, pain and trismus after zygomatico-orbital fracture surgery, improving patients' postoperative quality of life. A total of 30 patients were assigned for treatment of zygomatico-orbital fractures and were randomly divided into treatment either with or without kinesiologic tape. Tape was applied directly after surgery and maintained for at least 5 days postoperatively. Facial swelling was quantified using a five-line measurement at six specific time points. Pain and degree of mouth opening was measured. Patient's subjective feeling and satisfaction was queried. The results of this study show that application of kinesiologic tape after zygomatico-orbital surgery significantly reduced the incidence of swelling with an earlier swelling maximum, and decreased the maximum turgidity for more than 60% during the first 2 days after surgery. Although, kinesiologic tape has no significant influence on pain control and trismus, mouth opening increased earlier after operation in the kinesiologic tape group compared to the no-kinesiologic tape group. Furthermore, patients with kinesiologic tape felt significantly lower morbidity than those without kinesiologic tape. Therefore kinesiologic tape is a promising, simple, less traumatic, economical approach, which is free from adverse reaction and improves patients' quality of life. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  7. Presentation and management of facial swellings of odontogenic origin in children.

    Science.gov (United States)

    Michael, J A; Hibbert, S A

    2014-08-01

    To determine the characteristics, aetiology and management of facial swellings of odontogenic origin in the paediatric population. Prospective study of children with facial swellings of odontogenic origin. All children who presented to the Departments of Paediatric Dentistry of the Westmead Centre for Oral Health and the Children's Hospital at Westmead with a facial swelling of odontogenic origin over a 12 month period were identified and included in the study. Treating clinicians completed a standardised data collection sheet to record information relating to patient demographics, medical history, dental history, history of current episode of facial swelling of odontogenic origin, examination findings and management. Data were entered in Microsoft(®) Excel and statistical analysis carried out using Statistical Analysis Software(®) version 9.3. Two hundred and fifty-three children were included in the study, with a mean age of 6.3 years. Sixteen percent of children were admitted for intravenous antibiotics, surgical management and supportive care. For the remaining children not admitted, a range of management approaches were undertaken. These included immediate surgical management with or without oral antibiotics, delayed surgical management following a course of oral antibiotics, or oral antibiotics alone, where the cause of the odontogenic infection had already been removed. For 2% of children, a delayed surgical management approach was unsuccessful and the children were admitted. Management options for children presenting with facial swellings of odontogenic origin include admission to hospital for intravenous antibiotics and acute surgical management, immediate surgical management with or without a course of oral antibiotics or initial management involving a course of oral antibiotics, with definitive dental treatment being provided after resolution of the acute odontogenic infection.

  8. Severe Embrittlement of Neutron Irradiated Austenitic Steels Arising from High Void Swelling

    International Nuclear Information System (INIS)

    Neustroev, V.S.; Garner, F.

    2007-01-01

    Full text of publication follows: Data are presented from BOR-60 irradiations showing that significant radiation-induced swelling causes severe embrittlement in austenitic stainless steels, reducing the service life of structural components. Similar loss of ductility is expected when swelling arises in fusion and light water reactor environments. Above 7-16% swelling there is complete loss of ductility, with the onset of ductility loss beginning at lower swelling in ring-pull tensile tests than for flat tensile specimens. For steels that develop extensive precipitation during irradiation, the critical swelling level is even lower. A model is presented to demonstrate the effect of voids acting alone to produce the embrittlement. Although voids are not very effective hardeners, they are very effective to generate stress concentrations between voids. The stress concentration ratio increases strongly when the void diameter exceeds ∼40% of the void-to-void separation distance. When the volume fraction of voids is rather high (about 16 % and higher), a geometric situation develops where it is possible to create an intense field of deformation glide planes residing at an angle of 45 deg. to the void-to-void axis. Significant localized flow then proceeds on these planes for specimen stress levels that are significantly lower than the yield stress. Voids also segregate nickel to their surfaces such that flow localization occurs in the low-nickel inter-void regions to produce strain-induced martensite, which is further accelerated by stress concentrations at the advancing crack tip, leading to catastrophic failure. (authors)

  9. Influences of neutralization of superabsorbent hydrogel from hydroxyethyl cellulose on water swelling capacities

    Science.gov (United States)

    Adair, Ajaman; Klinpituksa, Pairote; Kaesaman, Azizon

    2017-08-01

    In this research, superabsorbent hydrogels were synthesized by graft copolymerization of hydroxyethyl cellulose (HEC) and polyacrylamide (PAM) under the initiation of potassium persulfate (KPS). The polymer networks were constructed using N,N'-methylenebisacrylamide (MBA), and the reaction was performed in an aqueous solution. The extent of grafting products was evaluated form grafting efficiency (%GE) and percentage of add-ons at HEC/AM ratios of 1: 10. The water swelling capacities, in terms of swelling capacity and weight loss, of resultant superabsorbent polymers (SAPs) after solvent extraction were determined for swelling behaviors. The result showed that the SAP had poor water absorption of approximately up to 23 g/g. To enhance swelling capacity of SAPs, an alkaline hydrolysis was done by using two types of alkaline bases, i.e., 2 M NaOH and 2 M KOH solution. The obtained treatment SAPs were neutralized by washing with distilled water and 0.5 M HCl until the liquors pH was nearly 7. They were found that the treatment SAPs showed the highest water absorption up to 317 g/g. Influences of various fluids pH values ranging between 4 and 10, on water swelling capacities of SAPs were also investigated. Under optimal pH value, the highest water absorptions of SAP was 382 g/g. To confirm the grafting reaction of PAM onto HEC backbone, FT-IR analysis was used. The results revealed absorption bands of the HEC backbone and new absorption bands from the grafted copolymer. Furthermore, the FT-IR spectrum was proved that washing with distilled water can alter the chemical functional group of SAPs.

  10. The swelling, microstructure, and hardening of wrought LCAC, TZM, and ODS molybdenum following neutron irradiation

    Science.gov (United States)

    Cockeram, B. V.; Smith, R. W.; Hashimoto, N.; Snead, L. L.

    2011-11-01

    TEM examinations and swelling measurements were performed on commercially available wrought Low Carbon Arc Cast (LCAC), La-oxide Oxide Dispersion Strengthened (ODS), and TZM molybdenum alloys following irradiation in the High Flux Isotope Reactor (HFIR) at 300 °C, 600 °C, and 900 °C to neutron fluences between 1.05 and 24.7 × 10 25 n/m 2 ( E > 0.1 MeV), or 0.6-13.1 dpa. The defect structure, hardening, and swelling were shown to be strongly dependent on irradiation temperature and starting microstructure. Irradiation at 300 °C results in the formation of a high number density of fine loops and voids (˜1 nm) that produce significant hardening and low swelling that is comparable for all alloys. Irradiation at 600 °C-784 °C produces a high number density of larger voids (5-6 nm) that results in significant hardening with the highest swelling. A low number density of the largest void sizes (8-30 nm) are formed for the 900 °C irradiation that result in low hardening and less swelling than observed for the 600 °C irradiation. The fine grain size of ODS Mo results in a higher concentration of denuded zones along grain boundaries and improved ductile-laminate toughening that results in improved resistance to irradiation embrittlement for the 600 °C irradiations. Irradiation-induced formation of precipitates rich in transmutation products is observed at the highest dose, and it is likely that these features exert an influence on subsequent void growth.

  11. Improved hemocompatibility of silicone rubber extracorporeal tubing via solvent swelling-impregnation of S-nitroso-N-acetylpenicillamine (SNAP) and evaluation in rabbit thrombogenicity model.

    Science.gov (United States)

    Brisbois, Elizabeth J; Major, Terry C; Goudie, Marcus J; Bartlett, Robert H; Meyerhoff, Mark E; Handa, Hitesh

    2016-06-01

    Blood-contacting devices, including extracorporeal circulation (ECC) circuits, can suffer from complications due to platelet activation and thrombus formation. Development of nitric oxide (NO) releasing polymers is one method to improve hemocompatibility, taking advantage of the ability of low levels of NO to prevent platelet activation/adhesion. In this study a novel solvent swelling method is used to load the walls of silicone rubber tubing with the NO donor S-nitroso-N-acetylpenicillamine (SNAP). This SNAP-silicone rubber tubing exhibits an NO flux of ca. 1×10(-10)molcm(-2)min(-1), which mimics the range of NO release from the normal endothelium, which is stable for at least 4h. Images of the tubing before and after swelling, obtained via scanning electron microscopy, demonstrate that this swelling method has little effect on the surface properties of the tubing. The SNAP-loaded silicone rubber and silicone rubber control tubing are used to fabricate ECC circuits that are evaluated in a rabbit model of thrombogenicity. After 4h of blood flow, the SNAP-loaded silicone rubber circuits were able to preserve the blood platelet count at 64% of baseline (vs. 12% for silicone rubber control). A 67% reduction in the degree of thrombus formation within the thrombogenicity chamber was also observed. This study demonstrates the ability to improve the hemocompatibility of existing/commercial silicone rubber tubing via a simple solvent swelling-impregnation technique, which may also be applicable to other silicone-based blood-contacting devices. Localized nitric oxide (NO) release can be achieved from biomedical grade polymers doped with S-nitroso-N-acetylpenicillamine (SNAP). Despite the promising in vitro and in vivo biocompatibility results reported for these NO releasing polymers, many of these materials may face challenges in being translated to clinical applications, especially in the areas of polymer processing and manufacturing. In this study, we report a solvent

  12. Preparation of novel nanoporous layered silicates by swelling of AMH-3 and their use in nanocomposite membranes for gas separation

    Science.gov (United States)

    Choi, Sunho

    Nanoporous layered materials can be described as a class of lamellar solids that have an intermediate structure between layered materials (e.g., clays) and nanoporous frameworks (e.g., zeolites). Among these, nanoporous layered silicates have been studied for various industrial applications since the rich intercalation chemistry of clays can be applied to yield their swollen and exfoliated derivatives. Their pore connectivity in the direction perpendicular to the layers has been expected to provide an ability of molecular recognition based on the size of permeating species. These unique structural characteristics are important in the membrane industry because the molecular sieving of permeable nanolayers, if exfoliated and incorporated in polymers, is able to enhance the separation properties of polymeric membranes. AMH-3, a layered silicate built of nanoporous layers and interlayer space occupied by cations and water molecules, has been known to have a unique three-dimensional eight membered-ring (8 MR) pore system. Due to its unique porosity, it has been proposed to use exfoliated layers of AMH-3 as a selectivity-enhancing additive in polymers for small molecule separation. However, experimental procedures for the AMH-3 swelling, required for the nanocomposite demonstrated. This research reveals a novel process for AMH-3 swelling, involving the sequential intercalation of surfactant molecules following proton exchange of interlayer cations in the presence of amino acids. Structural information of swollen AMH-3 is investigated using various characterization techniques and the emergence of structural changes indicates that it should be considered as a new nanoporous layered silicate rather than a simple intercalated derivative. Consequently, polymeric nanocomposites incorporating the nanoparticles of swollen AMH-3 are fabricated by solution blending. These nanocomposite membranes present substantial improvements of the hydrogen/carbon dioxide ideal selectivity more

  13. Structures in deposits from beach recovery, after erosion by swell waves around the southwestern coast of Aruba (Netherlands Antilles)

    NARCIS (Netherlands)

    Kohsiek, L.H.M.; Terwindt, J.H.J.; Hulsbergen, C.H.

    1984-01-01

    Hurricane- or storm-generated swell waves may cause erosion and deposition along coasts which are situated thousands of kilometers outside the generating wind field. Marked beach erosion, caused by such swell waves, was observed along the micro-tidal west coast of Aruba. During the process of

  14. Contribution to swelling analysis in ceramic nuclear fuels; Contribucion al analisis del hinchamiento de combustibles nucleares ceramicos

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Gonzalez, A.

    1976-07-01

    In this work a swelling phenomenological model containing several experimental observation is presented. Observations such as dissolution and redi solution of gas atoms, bubble nucleations in defects, dislocations and grain boundary, bubbles migration and coalescence are included. The model gives a bubbles distribution according to their size and position the swelling rate is calculated through the bubble distribution changes. (Author) 17 refs.

  15. Mathematical modelling and numerical solution of swelling of cartilaginous tissues. Part II: Mixed-hybrid finite element solution

    NARCIS (Netherlands)

    Malakpoor, K.; Kaasschieter, E.F.; Huyghe, J.M.

    2007-01-01

    Abstract: The swelling and shrinkage of biological tissues are modelled by a four-component mixture theory [J.M. Huyghe and J.D. Janssen, Int. J. Engng. Sci. 35 (1997) 793-802; K. Malakpoor, E.F. Kaasschieter and J.M. Huyghe, Mathematical modelling and numerical solution of swelling of cartilaginous

  16. Stepwise Swelling of a Thin Film of Lamellae-Forming Poly(styrene-b-butadiene) in Cyclohexane Vapor

    DEFF Research Database (Denmark)

    Di, Zhenyu; Posselt, Dorthe; Smilgies, Detlef-M.

    2012-01-01

    We investigated the swelling of a thin film of lamellae-forming poly(styrene-b-butadiene) in cyclohexane vapor. The vapor pressure and thus the degree of swelling of the film are increased in a stepwise manner using a custom-built sample cell. The resulting structural changes during and after each...

  17. On the dominance of pre-existing swells over wind seas along the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Aboobacker, V.M.; Rashmi, R.; Vethamony, P.; Menon, H.B.

    Wave data collected off Goa along the west coast of India during February 1996–May 1997 has been subjected to spectral analysis, and swell and wind sea parameters have been estimated by separation frequency method. Dominance of swells and wind seas...

  18. Origin of the large resistance to void swelling observed in Fe-35.5Ni-7.5Cr

    International Nuclear Information System (INIS)

    Brager, H.R.; Garner, F.A.

    1984-04-01

    While it is well known that increases in the nickel content of austenitic steels delay swelling, less attention has been paid to the fact that decreases in the chromium level from the usual 15 to 18% range also suppress swelling. Neutron irradiation studies show the longest postponement of swelling in Fe-Ni-Cr alloys occuring at approx. 35 wt % nickel and 7.5% chromium. The causes of the suppression and the subsequent loss of swelling resistance have been sought using electron microscopy and quantitative x-ray microanalysis. Swelling in this alloy is preceded by a substantial densification arising from large radiation-induced spinodal-like micro-oscillations in composition which appear to destroy the resistance to void nucleation, such that void nucleation is favored in the nickel-poor chromium-rich regions. Alloys optimization efforts now concentrate on solute additions which are designed to delay the microsegregation process

  19. Mass spectrometric and chemometric studies of thermoplastic properties of coals. 1. Chemometry of conventional, solvent swelling and extraction data of coals

    Energy Technology Data Exchange (ETDEWEB)

    Marzec, A.; Czajkowska, S.; Moszynski, J.; Schulten, H.-R. (Polish Academy of Sciences, Gliwice (Poland). Inst. of Coal Chemistry)

    Twenty-seven coals from Carboniferous seams in Poland were studied with the aim to find links between thermoplastic properties and chemical characteristics of the coals. Three sets of data were obtained for all the coals: (1) thermoplastic properties measured using the Gieseler plastometer; (2) yields of pyridine extractables and swelling measurements for pyridine residues; (3) ultimate, proximate, and petrographic analyses. The three data sets were evaluated using chemometric techniques with the purpose of looking for significant correlations between all the data. Temperature of softening is a linear regression of pyridine extractables and hydrogen content in coals as well as of swelling data. Temperatures of maximum fluidity and resolidification are correlated with each other and with oxygen, exinite, and moisture contents of the coals as well as with the swelling data. It has been concluded that temperature of softening is a colligative property and indicates a phase transition resulting in an increase of thermal induced mobility of coal material; the energy demand of the transition is dependent on contents of bulk components of coal system that were specified in this study. Temperatures of maximum fluidity and resolidification appear to have the same chemical background; i.e. the temperatures depend on the content of the same structural units or components. However, the means of chemical characterization of coal material used in this study were not capable of identifying them. Volatile matter and petrographic composition showed rather limited value as predictive means for some (T{sub F(max)} and T{sub R}) and no predictive value for the other thermoplastic properties. 20 refs., 1 fig., 5 tabs.

  20. Robust Polypropylene Fabrics Super-Repelling Various Liquids: A Simple, Rapid and Scalable Fabrication Method by Solvent Swelling.

    Science.gov (United States)

    Zhu, Tang; Cai, Chao; Duan, Chunting; Zhai, Shuai; Liang, Songmiao; Jin, Yan; Zhao, Ning; Xu, Jian

    2015-07-01

    A simple, rapid (10 s) and scalable method to fabricate superhydrophobic polypropylene (PP) fabrics is developed by swelling the fabrics in cyclohexane/heptane mixture at 80 °C. The recrystallization of the swollen macromolecules on the fiber surface contributes to the formation of submicron protuberances, which increase the surface roughness dramatically and result in superhydrophobic behavior. The superhydrophobic PP fabrics possess excellent repellency to blood, urine, milk, coffee, and other common liquids, and show good durability and robustness, such as remarkable resistances to water penetration, abrasion, acidic/alkaline solution, and boiling water. The excellent comprehensive performance of the superhydrophobic PP fabrics indicates their potential applications as oil/water separation materials, protective garments, diaper pads, or other medical and health supplies. This simple, fast and low cost method operating at a relatively low temperature is superior to other reported techniques for fabricating superhydrophobic PP materials as far as large scale manufacturing is considered. Moreover, the proposed method is applicable for preparing superhydrophobic PP films and sheets as well.

  1. A constitutive equation of creep, swelling and damage under neutron irradiation applicable to multiaxial and variable states of stress

    International Nuclear Information System (INIS)

    Murakami, Sumio; Mizuno, Mamoru.

    1992-01-01

    A constitutive equation of creep, swelling and damage under neutron irradiation applicable to multiaxial non-steady states of stress is developed. In the formulation of the constitutive equation, the creep under irradiation was divided into irradiation-affected thermal creep and irradiation-induced creep. Then the irradiation-affected thermal creep was formulated by extending the creep-hardening surface model to include the effects of neutron-irradiation and material damage. The Bailey-Norton creep law and Kachanov-Rabotnov creep-damage theory were employed. The effect of irradiation on thermal creep was described by expressing the material functions of the constitutive equation as functions of neutron flux φ and neutron fluence Φ. The constitutive equation of irradiation-induced creep was formulated by taking account of SIPA and CCG mechanisms and by representing the creep rate as a function of stress of order zero and one. Creep of 316 stainless steel under various conditions of irradiation and variable stress was analyzed in order to elucidate the validity and the utility of the proposed constitutive equation. (author)

  2. Role of lymphoscintigraphy in diagnosis and management of patients with leg swelling of unclear etiology

    International Nuclear Information System (INIS)

    Kalawat, Tek Chand; Chittoria, Ravi Kumar; Reddy, Praveen Kumar; Suneetha, Batchu; Narayan, Ravishwar; Ravi, Parthsarthi

    2012-01-01

    To study the utility of lymphoscintigraphy in detection of lymphatic obstruction in patients with leg swelling of unclear etiology, selection of site for nodo venous shunt procedure, and follow-up lymphoscintigraphic documentation of improved lymph flow in surgically treated limb. Twenty four consecutive patients with leg swelling, 10 male, 14 female with mean age 47 years, range from 13 years to 74 years underwent lymphoscintigraphy. All patients were referred from Department of Plastic Surgery, after initial work-up, and routine investigations to rule out the other causes of leg swelling. Both clinical and scintigraphic staging performed for all patients. All clinically and scintigraphically positive patients treated with decongestive lymphatic therapy (DLT). In addition to the DLT, those patients positive for unilateral or bilateral lymphedema, consented for surgical intervention, nodo venous shunt (NVS) in their only affected or one of the two affected lower limbs. Follow-up lymphoscintigraphy performed in operated cases after 3 months to 6 months of surgery, lymphoscintigraphy images of each patient in pre and post-surgery compared. In 20/24 cases (83%) of clinically positive leg swelling were found to be positive for lymphedema on lymphoscintigraphy and remaining, 4/24 were scintigraphically normal. Based on the clinical and lymphoscintigraphy staging, 03/20 cases (15%) had Grade I lymphedema, 01/20 (5%) Grade II lymphedema, 06/20 (30%) Grade III and remaining 10/20 (50%) had Grade IV lymphedema. 11/20 cases of Lymphedema (55%) were managed conservatively by only DLT and in remaining 09/20 cases (45%), who were case of Grade IV, lymphedema (five patients with unilateral and four patients with bilateral disease) initially treated with DLT, and on completion of DLT, undergone for NVS procedure, in their unilaterally affected lower limb or one of the two diseased lower limbs. All nine patients showed remarkable clinical improvement in leg swelling and their

  3. Facial Swelling

    Science.gov (United States)

    ... room right away. Start OverDiagnosisYou may have a skin infection such as BOILS, CARBUNCLES, orACNE. A boil is a large, pus-filled bump. Multiple boils are called carbuncles. Acne occurs when oil glands start producing more oil and block pores. Acne can result in blackheads, whiteheads and pimples. ...

  4. Enrichment and Broad Representation of Plant Biomass-Degrading Enzymes in the Specialized Hyphal Swellings of Leucoagaricus gongylophorus, the Fungal Symbiont of Leaf-Cutter Ants

    Energy Technology Data Exchange (ETDEWEB)

    Aylward, Frank O.; Khadempour, Lily; Tremmel, Daniel; McDonald, Bradon R.; Nicora, Carrie D.; Wu, Si; Moore, Ronald J.; Orton, Daniel J.; Monroe, Matthew E.; Piehowski, Paul D.; Purvine, Samuel O.; Smith, Richard D.; Lipton, Mary S.; Burnum-Johnson, Kristin E.; Currie, Cameron R.

    2015-08-28

    Leaf-cutter ants are prolific and conspicuous Neotropical herbivores that derive energy from specialized fungus gardens they cultivate using foliar biomass. The basidiomycetous cultivar of the ants, Leucoagaricus gongylophorus, produces specialized hyphal swellings called gongylidia that serve as the primary food source of ant colonies. Gongylidia also contain lignocellulases that become concentrated in ant digestive tracts and are deposited within fecal droplets onto fresh foliar material as it is foraged by the ants. Although the enzymes concentrated by L. gongylophorus within gongylidia are thought to be critical to the initial degradation of plant biomass, only a few enzymes present in these hyphal swellings have been identified. Here we use proteomic methods to identify proteins present in the gongylidia of three Atta cephalotes colonies. Our results demonstrate that a diverse but consistent set of enzymes is present in gongylidia, including numerous lignocellulases likely involved in the degradation of polysaccharides, plant toxins, and proteins. Overall, gongylidia contained over three-quarters of all lignocellulases identified in the L. gongylophorus genome, demonstrating that the majority of the enzymes produced by this fungus for biomass breakdown are ingested by the ants. We also identify a set of 23 lignocellulases enriched in gongylidia compared to whole fungus garden samples, suggesting that certain enzymes may be particularly important in the initial degradation of foliar material. Our work sheds light on the complex interplay between leaf-cutter ants and their fungal symbiont that allows for the host insects to occupy an herbivorous niche by indirectly deriving energy from plant biomass.

  5. Mechanical, thermal and swelling properties of phosphorylated nanocellulose fibrils/PVA nanocomposite membranes.

    Science.gov (United States)

    Niazi, Muhammad Bilal Khan; Jahan, Zaib; Berg, Sigrun Sofie; Gregersen, Øyvind Weiby

    2017-12-01

    Cellulose nanofibrils (CNF) have strong reinforcing properties when incorporated in a compatible polymer matrix. This work reports the effect of the addition of phosphorylated nanocellulose (PCNF) on the mechanical, thermal and swelling properties of poly(vinyl alcohol) (PVA) nanocomposite membranes. The incorporation of nanocellulose in PVA reduced the crystallinity at 0%RH. However, when the films were exposed to higher humidities the crystallinity increased. No apparent trend is observed for mechanical properties for dry membranes (0% RH). However, at 93% RH the elastic modulus increased strongly from 0.12MPa to 0.82MPa when adding 6% PCNF. At higher humidities, the moisture uptake has large influence on storage modulus, tan δ and tensile properties. Membranes containing 1% PCNF absorbed most moisture. Swelling, thermal and mechanical properties indicate a good potential for applying of PVA/phosphorylated nanocellulose composite membranes for CO 2 separation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Recurrent lip swelling as a late presentation of Kawasaki disease: Case report and review of literature.

    Science.gov (United States)

    Faden, Asmaa

    2013-01-01

    Kawasaki Disease (KD) is an acute systemic vasculitis of unknown etiology. In many developed countries, KD has replaced rheumatic heart disease as the leading cause of acquired heart disease in children. Among the classical criteria for a diagnosis of KD are oral manifestations such as strawberry tongue, erythematous cracked lip, and oropharyngeal mucositis. We report the case of a 24-year-old Saudi female with a history of Kawasaki disease who presented to our oral medicine clinic with recurrent painless swelling of the upper lip. As lip swelling has not previously been reported as an oral manifestation of KD, this case represents a novel presentation of recurrent Kawasaki disease in an adult female.

  7. Delayed resolution of eyelid swelling in preseptal cellulitis in a child: beware of causing occlusion amblyopia

    Science.gov (United States)

    Upendran, Muralidharan R; McLoone, Eibhlin

    2013-01-01

    A 7-month-old child presented with a 6-day history of right eyelid swelling and redness. She was being treated with chloramphenicol ointment and oral flucloxacillin by the general practitioner. Clinical examination revealed features of preseptal cellulitis. There was no evidence of orbital involvement and the child was generally well otherwise. Her oral antibiotics were changed and she was adviced to attend for a review in 2 days time. However, the child did not return for a review. Three weeks later following resolution of the eyelid swelling, the child represented with a divergent squint in the right eye. Clinical and orthoptic investigations suggested occlusion amblyopia. The child is currently receiving patching treatment for the amblyopia and is awaiting surgery for squint eye. PMID:23476010

  8. Activity-dependent astrocyte swelling is mediated by pH-regulating mechanisms

    DEFF Research Database (Denmark)

    Larsen, Brian Roland; MacAulay, Nanna

    2017-01-01

    During neuronal activity in the mammalian brain, the K(+) released into the synaptic space is initially buffered by the astrocytic compartment. In parallel, the extracellular space (ECS) shrinks, presumably due to astrocytic cell swelling. With the Na(+) /K(+) /2Cl(-) cotransporter and the Kir4.......1/AQP4 complex not required for the astrocytic cell swelling in the hippocampus, the molecular mechanisms underlying the activity-dependent ECS shrinkage have remained unresolved. To identify these molecular mechanisms, we employed ion-sensitive microelectrodes to measure changes in ECS, [K(+) ]o and [H......(+) ]o /pHo during electrical stimulation of rat hippocampal slices. Transporters and receptors responding directly to the K(+) and glutamate released into the extracellular space (the K(+) /Cl(-) cotransporter, KCC, glutamate transporters and G protein-coupled receptors) did not modulate...

  9. Impetigo presenting as an acute necrotizing swelling of the lower lip in an adult patient.

    Science.gov (United States)

    Ghafoor, Mohammed; Halsnad, Moorthy; Fowell, Christopher; Millar, Brian G

    2012-06-01

    The authors present an unusual case of an acute swelling of the lower lip and septicemia in a 35-year-old, recent immigrant male arriving from India. The patient presented in our emergency department with a 48-hour history of a worsening, painful swelling of the lower lip. On presentation, he was pyrexial and the lip was found to be acutely inflamed with honey-colored crusting, pustular lesions, and induration . A diagnosis of impetigo leading to necrosis of the lip was established, a rare phenomenon potentially resulting in significant tissue destruction. Appropriate medical management achieved a good outcome and prevented disabling tissue loss of the orofacial region. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Plasticity, Swell-Shrink, and Microstructure of Phosphogypsum Admixed Lime Stabilized Expansive Soil

    Directory of Open Access Journals (Sweden)

    Jijo James

    2016-01-01

    Full Text Available The study involved utilization of an industrial waste, Phosphogypsum (PG, as an additive to lime stabilization of an expansive soil. Three lime dosages, namely, initial consumption of lime (ICL, optimum lime content (OLC, and less than ICL (LICL, were identified for the soil under study for stabilizing the soil. Along with lime, varying doses of PG were added to the soil for stabilization. The effect of stabilization was studied by performing index tests, namely, liquid limit, plastic limit, shrinkage limit, and free swell test, on pulverized remains of failed unconfined compression test specimens. The samples were also subjected to a microstructural study by means of scanning electron microscope. Addition of PG to lime resulted in improvement in the plasticity and swell-shrink characteristics. The microstructural study revealed the formation of a dense compact mass of stabilized soil.

  11. Effect of temperature changes on swelling and creep of AISI 316

    International Nuclear Information System (INIS)

    Garner, F.A.; Gilbert, E.R.; Gelles, D.S.; Foster, J.P.

    1980-04-01

    A number of previous publications have shown that the swelling of cold-worked AISI 316 is quite sensitive to changes in temperature which occur during irradiation. In this report those data are expanded and reanalyzed to show that the concurrent irradiation creep is also quite sensitive to changes in irradiation temperature. An explanation is advanced to explain this behavior in terms of the sensitivity to temperture history of the radiation-induced microchemical evolution of this steel. In particular, the sensitivity to temperature history of the radiation-stabilized gamma prime phase is invoked to explain the enhanced creep and swelling behavior of AISI 316 components which experienced either gradual or abrupt decreases in temperature. The phase development observed in this steel in response to temperature changes during irradiation is also compared to the similar behavior found in aged specimens subjected to isothermal irradiation

  12. Anomalous swelling of multilamellar lipid bilayers in the transition region by renormalization of curvature elasticity

    DEFF Research Database (Denmark)

    Callisen, Thomas Hønger; Mortensen, Kell; Ipsen, John Hjorth

    1994-01-01

    Small-angle neutron scattering is used to determine the temperature dependence of the lamellar repeat distance in an aqueous multilamellar solution of phospholipid bilayers. A thermal anomaly in the swelling behavior is observed at the bilayer phase transition. The anomalous behavior can be suppr......Small-angle neutron scattering is used to determine the temperature dependence of the lamellar repeat distance in an aqueous multilamellar solution of phospholipid bilayers. A thermal anomaly in the swelling behavior is observed at the bilayer phase transition. The anomalous behavior can...... be suppressed by varying the lipid acyl-chain length or by alloying with a molecular stiffening agent. The experimental results are explained in terms of renormalization of the bilayer curvature elasticity and by using a theory of repulsive interlamellar undulation forces....

  13. A model for swelling changes in a covalently crosslinked gel caused by unfolding of folded domains

    Czech Academy of Sciences Publication Activity Database

    Dušek, Karel; Dušková, Miroslava; Stewart, R.; Kopeček, J.

    2001-01-01

    Roč. 47, 3-4 (2001), s. 351-358 ISSN 0170-0839 R&D Projects: GA AV ČR IAA4050808; GA AV ČR KSK2050602 Grant - others:XE(XC) IC15CT96-0756 Institutional research plan: CEZ:AV0Z4050913 Keywords : polymer gel * swelling * phase transition Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.880, year: 2001

  14. Swelling/deswelling of polyacrylamide gels in aqueous NaCl solution

    Indian Academy of Sciences (India)

    and the parameter Y = 〈I(q)〉E/〈I(q)〉T. 2.4 Flory–Huggin's theory of swelling. According to Flory–Huggin's theory, when the as-prepared non-ionic hydrogel is immersed in a solvent and allowed to reach equilibrium with its surroundings, two forces act on the hydrogel [19,20]. One is the osmotic pressure arising from mixing ...

  15. How Do Organic Vapors Swell Ultra-Thin PIM-1 Films?

    KAUST Repository

    Ogieglo, Wojciech

    2017-06-22

    Dynamic sorption of ethanol and toluene vapor into ultra-thin supported PIM-1 films down to 6 nm are studied with a combination of in-situ spectroscopic ellipsometry and in-situ X-ray reflectivity. Both ethanol and toluene significantly swell the PIM-1 matrix and, at the same time, induce persistent structural relaxations of the frozen-in glassy PIM-1 morphology. For ethanol below 20 nm three effects were identified. First, the swelling magnitude at high vapor pressures is reduced by about 30% as compared to thicker films. Second, at low penetrant activities (below 0.3 p/p0) films below 20 nm are able to absorb slightly more penetrant as compared with thicker films despite similar swelling magnitude. Third, for the ultra-thin films the onset of the dynamic penetrant-induced glass transition Pg has been found to shift to higher values indicating higher resistance to plasticization. All of these effects are consistent with a view where immobilization of the super-glassy PIM-1 at the substrate surface leads to an arrested, even more rigid and plasticization-resistant, yet still very open, microporous structure. PIM-1 in contact with the larger and more condensable toluene shows very complex, heterogeneous swelling dynamics and two distinct penetrant-induced relaxation phenomena, probably associated with the film outer surface and the bulk, are detected. Following the direction of the penetrant\\'s diffusion the surface seems to plasticize earlier than the bulk and the two relaxations remain well separated down to 6 nm film thickness, where they remarkably merge to form just a single relaxation.

  16. Strategies used to inhibit postoperative swelling following removal of impacted lower third molar

    Science.gov (United States)

    Sortino, Francesco; Cicciù, Marco

    2011-01-01

    Postoperative swelling following different surgical strategies is an area of great interest. The main part of literature on the topic deals with swelling after extraction of low impacted third molar. In this review, we have analyzed publications of the last 20 years with a pubmed search using the following key words: impacted third molar, swelling third molar, wisdom tooth, edema jaw, corticosteroids and extraction third molar, antibiotic prophylaxis and tooth extraction. Attention has often been focused on corticosteroid therapy administered by diverse routes (orally, IV, IM, topically) and at different time schedules (before or after surgery or both). This investigation revealed how the use of different molecules and dosages makes the obtained results hardly comparable. Similar conclusions can be drawn from studies aimed at evaluating the efficacy of antibiotic therapy administered either before or after surgery. A complete review has also to take into account different surgical strategies used including various flaps, no traumatic osteothomy, and primary or secondary closure. The use of pharmacological therapy and application of an ice pack is critical in the postoperative period and has always provided positive results. However, even if it is difficult to come to definite conclusions, due to the variability of the design of studies analyzed, the postoperative discomfort identified with edema, pain and trismus following wisdom tooth removal is influenced by various factors such as the difficulty of the surgical procedure involved, age and gender of the patient, and experience of the surgeon. The pharmacological therapy when performed with corticosteroids seems to improve control of the postoperative swelling related with this kind of surgeries. PMID:22135686

  17. Swelling of the temporal region: a case of benign masticatory muscle hypertrophy

    DEFF Research Database (Denmark)

    Gniadecka, M; Weismann, K; Herning, Gudrun Margrethe

    1997-01-01

    A 35-year-old Caucasian woman had bilateral indolent swelling of the temporal regions. Imaging studies with nuclear magnetic resonance, ultrasonography and histopathological investigation revealed enlargement of the temporal and masseter muscles, with no pathology in the skin or subcutaneous tiss....... A small prolactinoma of the pituitary gland was incidentally found. The condition, designated benign masticatory muscle hypertrophy, should be distinguished from similar diseases affecting the skin and the subcutaneous tissue of the scalp. The cause remains unknown...

  18. Influence of burnup rate on the stability of nuclear fuel swelling, Annex

    International Nuclear Information System (INIS)

    Lazarevic, Dj.

    1966-01-01

    Positive influence of the burnup rate and precipits of the second phase on the fuel stability concerning swelling has been found according to the published results. This paper proposed a dynamic equilibrium model for the precipits state as a function of reactor power density and fuel temperature. It was estimated that the metal fuel can achieve rather high burnup rate in the heavy water power reactors [fr

  19. The swelling of clays and its effects on underground storage works

    International Nuclear Information System (INIS)

    Gaombalet, J.

    2004-03-01

    The aim of this work is to study the swelling of clays and more generally the clayey media in relation to storage. Different types of clays, natural or reworked, have been studied in a rheological point of view, with the aim to result in behavior laws allowing to reproduce some identified phenomena. The first part of this work is a presentation of the concept of geological underground storage. The second part deals with clays. They are studied at a microscopic level and their macroscopic behavior are presented too. In the third part, the equations of the couplings: mechanics/transport in the porous media in general and applied to clays are formulated. Three types of clays have particularly been studied: a stiff clay, a plastic clay and a reworked clay. The following part deals with the swelling of clays. The analysis carried out through a bibliographical study has led us to propose a behavior law for the swelling-retirement. This part concerns essentially the mechanics. The behavior model, which integrates the swelling, involves the concentration of the ions present in solution in the interstitial water. Concerning the transport, of water or ions, the research of coherent models have led us to revise some models described in the second part and concerning the transport of solutions in porous media. The last part concerns the computerized simulation. It begins by a brief description of the computer code. We show how the equations described in the work are dealt with in the computer code. At last, some storage applications (computerized simulation) are given. (O.M.)

  20. Activity-dependent astrocyte swelling is mediated by pH-regulating mechanisms.

    Science.gov (United States)

    Larsen, Brian Roland; MacAulay, Nanna

    2017-10-01

    During neuronal activity in the mammalian brain, the K + released into the synaptic space is initially buffered by the astrocytic compartment. In parallel, the extracellular space (ECS) shrinks, presumably due to astrocytic cell swelling. With the Na + /K + /2Cl - cotransporter and the Kir4.1/AQP4 complex not required for the astrocytic cell swelling in the hippocampus, the molecular mechanisms underlying the activity-dependent ECS shrinkage have remained unresolved. To identify these molecular mechanisms, we employed ion-sensitive microelectrodes to measure changes in ECS, [K + ] o and [H + ] o /pH o during electrical stimulation of rat hippocampal slices. Transporters and receptors responding directly to the K + and glutamate released into the extracellular space (the K + /Cl - cotransporter, KCC, glutamate transporters and G protein-coupled receptors) did not modulate the extracellular space dynamics. The HCO3--transporting mechanism, which in astrocytes mainly constitutes the electrogenic Na + / HCO3- cotransporter 1 (NBCe1), is activated by the K + -mediated depolarization of the astrocytic membrane. Inhibition of this transporter reduced the ECS shrinkage by ∼25% without affecting the K + transients, pointing to NBCe1 as a key contributor to the stimulus-induced astrocytic cell swelling. Inhibition of the monocarboxylate cotransporters (MCT), like-wise, reduced the ECS shrinkage by ∼25% without compromising the K + transients. Isosmotic reduction of extracellular Cl - revealed a requirement for this ion in parts of the ECS shrinkage. Taken together, the stimulus-evoked astrocytic cell swelling does not appear to occur as a direct effect of the K + clearance, as earlier proposed, but partly via the pH-regulating transport mechanisms activated by the K + -induced astrocytic depolarization and the activity-dependent metabolism. © 2017 Wiley Periodicals, Inc.

  1. Chronic swelling from entrapment of acrylic resin in a surgical extraction site

    OpenAIRE

    Weiting Ho; Pin-Chuang Lai; John D Walters

    2010-01-01

    When acrylic resin is inadvertently embedded in oral tissue, it can result in a pronounced chronic inflammatory response. This report describes a case in which temporary crown and bridge resin was forced into a surgical extraction site after the two adjacent teeth were prepared for a bridge immediately following extraction of a maxillary premolar. The patient experienced swelling at the extraction site over a ten month period despite treatment with antibiotics and anti-inflammatory drugs. Aft...

  2. Strategies used to inhibit postoperative swelling following removal of impacted lower third molar

    Directory of Open Access Journals (Sweden)

    Francesco Sortino

    2011-01-01

    Full Text Available Postoperative swelling following different surgical strategies is an area of great interest. The main part of literature on the topic deals with swelling after extraction of low impacted third molar. In this review, we have analyzed publications of the last 20 years with a pubmed search using the following key words: impacted third molar, swelling third molar, wisdom tooth, edema jaw, corticosteroids and extraction third molar, antibiotic prophylaxis and tooth extraction. Attention has often been focused on corticosteroid therapy administered by diverse routes (orally, IV, IM, topically and at different time schedules (before or after surgery or both. This investigation revealed how the use of different molecules and dosages makes the obtained results hardly comparable. Similar conclusions can be drawn from studies aimed at evaluating the efficacy of antibiotic therapy administered either before or after surgery. A complete review has also to take into account different surgical strategies used including various flaps, no traumatic osteothomy, and primary or secondary closure. The use of pharmacological therapy and application of an ice pack is critical in the postoperative period and has always provided positive results. However, even if it is difficult to come to definite conclusions, due to the variability of the design of studies analyzed, the postoperative discomfort identified with edema, pain and trismus following wisdom tooth removal is influenced by various factors such as the difficulty of the surgical procedure involved, age and gender of the patient, and experience of the surgeon. The pharmacological therapy when performed with corticosteroids seems to improve control of the postoperative swelling related with this kind of surgeries.

  3. Intrauterine Contraceptive Device Migration Presenting as Abdominal Wall Swelling: A Case Report

    Directory of Open Access Journals (Sweden)

    Imtiaz Wani

    2011-01-01

    Full Text Available A number of complications are reported with the use of intrauterine contraceptive devices. These may pursue asymptomatic course or present as an acute abdomen after migration into peritoneal cavity. The authors here are reporting an abdominal wall swelling caused by transuterine migration of a copper intrauterine contraceptive device in a 28-year-old female. An open approach was used, and impacted foreign body was retrieved.

  4. Broadband polarizing films by photopolymerization-induced phase separation and in situ Swelling

    International Nuclear Information System (INIS)

    Fan, B.; Vartak, S.; Eakin, J. N.; Faris, S. M.

    2008-01-01

    This letter describes the spectral broadening of cholesteric liquid crystal films prepared from a blend comprising a cross-linkable liquid crystal polymer and a noncross-linkable low-molecular-weight liquid crystal. The bandwidth of the broadened reflection band can be increased by several times upon photopolymerization. The spectral broadening arises from the formation of gradient pitch across the film thickness. It is shown that both phase separation and in situ swelling are important mechanisms for the resulting film structure

  5. MRI findings of acute cerebral swelling and brain edema in the acute stage

    International Nuclear Information System (INIS)

    Oki, Hideo; Ueda, Shin; Matsumoto, Keizo; Kashihara, Michiharu; Furuichi, Masashi.

    1988-01-01

    We report two cases, one of acute cerebral swelling and the other with a major stroke, whose MRI has shown very interesting findings. Case 1, a 32-year-old male, was admitted to our service because of a lowering of his consciousness immediately after a head injury. On admission, the patient was semicomatous (E 1 M 2 V 1 , with anisocoria (R > L). His plain skull X-ray was normal. A CT scan, however, demonstrated right isodensity hemispheric swelling associated with a subarachnoid hemorrhage in the right Sylvian fissure. A right carotid angiogram showed no vascular disorders. MR imaging of the spin density demonstrated a hyperintensitive thickening of the gray matter in the whole right hemisphere. Case 2, a 58-year-old female, was admitted because of a sudden onset of loss of consciousness, with right hemiparesis and dysarthria. On admission, her consciousness was semicomatous (E 1 M 3 V 1 ), and it deteriorated to a deep coma 1 hour later. A CT scan demonstrated a diffuse left hemispheric low density, with a finding of hemorrhagic infarction in the basal ganglia. MR imaging of the spin density showed a hyperintensitive thickening of the gray matter resembling that of Case 1. The findings of the spin-echo images of our two cases showed a hyperintensitive thickening of the gray matter in both. The hyperintensity and thickening of the gray matter apparently indicated a sort of hyperemia and brain edema. These findings led us to suspect that the hyperemia associated with acute cerebral swelling and ischemic brain edema of our two cases originated in the gray matter, although it has been considered that the pathogenesis of acute cerebral swelling is not known and that brain edema, especially vasogenic edema, will mostly develop in the white matter rather than in the gray matter. (author)

  6. Lipophilic Super-Absorbent Swelling Gels as Cleaners for Use on Weapons Systems and Platforms

    Science.gov (United States)

    2014-02-01

    lipophilic anion) to form lipophilic ionic acrylate monomer . Copolymerization of the product from Step 2 with the polymer backbone octadecyl...vacuum overnight. SA-co-EGDMA with two crosslinker ratios were prepared by radical copolymerization , which are represented as NG- 18-x% (x= 1 or 0.5; x...technology based on lipophilic super-absorbent swelling gels that is VOC-exempt, HAP- free , non-toxic, non-corrosive, non-ozone depleting, and

  7. Frontal and orbital bone infarctions causing periorbital swelling in patients with sickle cell anemia

    International Nuclear Information System (INIS)

    Garty, I.; Koren, A.; Garzozi, H.

    1984-01-01

    Two cases of unilateral and bilateral periorbital hematomas occurred in patients with sickle cell anemia. The cause of periorbital swelling in these cases was found to be orbital and frontal bone infarctions, respectively, diagnosed by technetium Tc 99m medronate bone scintigraphy. To our knowledge, periorbital bone infarction, as a part of the differential diagnosis of periorbital hematoma and as part of the possible ocular manifestations in patients with sickle cell anemia, has not previously been described

  8. Multiple myeloma presenting as a painful mandibular swelling: a case report.

    Science.gov (United States)

    Chindia, M L; Riyat, M S; Nyong'o, A

    2001-06-01

    Multiple myeloma is a disease characterized by monoclonal proliferation of plasma cells, the most differentiated stage of B-cells. Primary manifestation of multiple myeloma in the jawbones is rare. In the case reported here, a 29-year-old woman who presented with a right mandibular swelling after extraction of a mobile painful tooth turned out to have multiple myeloma. Current diagnostic criteria and management strategies of the disease are discussed.

  9. Dimensional stability and anisotropy of SiC and SiC-based composites in transition swelling regime

    Science.gov (United States)

    Katoh, Yutai; Koyanagi, Takaaki; McDuffee, Joel L.; Snead, Lance L.; Yueh, Ken

    2018-02-01

    Swelling, or volumetric expansion, is an inevitable consequence of the atomic displacement damage in crystalline silicon carbide (SiC) caused by energetic neutron irradiation. Because of its steep temperature and dose dependence, understanding swelling is essential for designing SiC-based components for nuclear applications. In this study, swelling behaviors of monolithic CVD SiC and nuclear grade SiC fiber - SiC matrix (SiC/SiC) composites were accurately determined, supported by the irradiation temperature determination for individual samples, following neutron irradiation within the lower transition swelling temperature regime. Slightly anisotropic swelling behaviors were found for the SiC/SiC samples and attributed primarily to the combined effects of the pre-existing microcracking, fiber architecture, and specimen dimension. A semi-empirical model of SiC swelling was calibrated and presented. Finally, implications of the refined model to selected swelling-related issues for SiC-based nuclar reactor components are discussed.

  10. Swelling-induced morphology reconstruction in block copolymer nanorods: kinetics and impact of surface tension during solvent evaporation.

    Science.gov (United States)

    Wang, Yong; Tong, Ling; Steinhart, Martin

    2011-03-22

    Nanoscopic domain structures of BCP nanorods can be converted into well-defined mesopore systems by swelling the BCP minority component with a selective solvent at temperatures below the bulk glass transition temperature of the nonswelling matrix. The initial stage of this process involves rapid morphology reconstruction of the nonswelling majority domains to accommodate the increased volume of the swelling minority domains caused by rapid solvent uptake. Morphology reconstruction slows down once entropic restoring forces of the swelling chains impede further uptake of swelling agent. Upon evaporation of the swelling agent, mesopores form in place of the swollen domains as the swollen minority blocks undergo entropic relaxation while intermediate nonequilibrium morphologies in the BCP nanorods are fixated by the reconstructed majority component. The surface area of mesopores developing when swollen cylindrical minority domains collapse may be minimized by the growth of Rayleigh instabilities. Depending on swelling temperature, swelling agent, and BCP architecture, BCP nanorods with one or several cylindrical channels undulated or uniform in diameter running along their long axes, linear strings of spherical cavities, and continuous mesopore systems can be obtained.

  11. Disassembly of actin structures by nanosecond pulsed electric field is a downstream effect of cell swelling.

    Science.gov (United States)

    Pakhomov, Andrei G; Xiao, Shu; Pakhomova, Olga N; Semenov, Iurii; Kuipers, Marjorie A; Ibey, Bennett L

    2014-12-01

    Disruption of the actin cytoskeleton structures was reported as one of the characteristic effects of nanosecond-duration pulsed electric field (nsPEF) in both mammalian and plant cells. We utilized CHO cells that expressed the monomeric fluorescent protein (mApple) tagged to actin to test if nsPEF modifies the cell actin directly or as a consequence of cell membrane permeabilization. A train of four 600-ns pulses at 19.2 kV/cm (2 Hz) caused immediate cell membrane poration manifested by YO-PRO-1 dye uptake, gradual cell rounding and swelling. Concurrently, bright actin features were replaced by dimmer and uniform fluorescence of diffuse actin. To block the nsPEF-induced swelling, the bath buffer was isoosmotically supplemented with an electropore-impermeable solute (sucrose). A similar addition of a smaller, electropore-permeable solute (adonitol) served as a control. We demonstrated that sucrose efficiently blocked disassembly of actin features by nsPEF, whereas adonitol did not. Sucrose also attenuated bleaching of mApple-tagged actin in nsPEF-treated cells (as integrated over the cell volume), although did not fully prevent it. We conclude that disintegration of the actin cytoskeleton was a result of cell swelling, which, in turn, was caused by cell permeabilization by nsPEF and transmembrane diffusion of solutes which led to the osmotic imbalance. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Prediction of postoperative facial swelling, pain and trismus following third molar surgery based on preoperative variables

    Science.gov (United States)

    de Souza-Santos, Jadson A.; Martins-Filho, Paulo R.; da Silva, Luiz C.; de Oliveira e Silva, Emanuel D.; Gomes, Ana C.

    2013-01-01

    Objective: This paper investigates the relationship between preoperative findings and short-term outcome in third molar surgery. Study design: A prospective study was carried out involving 80 patients who required 160 surgical extractions of impacted mandibular third molars between January 2009 and December 2010. All extractions were performed under local anesthesia by the same dental surgeon. Swelling and maximal inter-incisor distance were measured at 48 h and on the 7th day postoperatively. Mean visual analogue pain scores were determined at four different time periods. Results: One-hundred eight (67.5%) of the 160 extractions were performed on male subjects and 52 (32.5%) were performed on female subjects. Median age was 22.46 years. The amount of facial swelling varied depending on gender and operating time. Trismus varied depending on gender, operating time and tooth sectioning. The influence of age, gender and operating time varied depending on the pain evaluation period (p trismus and pain) differ depending on the patients’ characteristics (age, gender and body mass index). Moreover, surgery characteristics such as operating time and tooth sectioning were also associated with postoperative variables. Key words:Third molar extraction, pain, swelling, trismus, postoperative findings, prediction. PMID:23229245

  13. Recurrent parotid swelling secondary to masseter muscle hypertrophy: a multidisciplinary diagnostic and therapeutic approach.

    Science.gov (United States)

    Capaccio, Pasquale; Gaffuri, Michele; Pignataro, Lorenzo; Assandri, Fausto; Pereira, Pollyanna; Farronato, Giampietro

    2016-11-01

    To present a patient with an atypical recurrent parotid swelling due to masseter muscle hypertrophy and the diagnostic/therapeutic assessment to treat this condition. A patient referring recurrent right facial swelling underwent a complete multidisciplinary assessment of the parotid region that revealed masseter muscle hypertrophy, confirmed by means of clinical (otolaryngological and gnathological evaluation), radiological (utrasonography, dynamic magnetic resonance imaging, and cone beam computed tomography), instrumental (electromyography to evaluate the right masseter muscle function and kinesiography to evaluate maximum right deflection - MaxRDefl and maximum opening - MaxMO) and sialendoscopy assessment where T0 indicates the pre-treatment values. All electromyographic and kinesiographic parameters were evaluated six months after the orthodontic application of a neuromuscular orthosis at T1. At T1, the effectiveness of the orthodontic therapy was demonstrated by the complete resolution of symptoms, and instrumental results documented more efficient muscle activity at rest and during clenching and a better mandibular position. At EMG T1, the resting and post-TENS values were, respectively, 1.2 and 1.8 microV. At kinesiography, MaxRDefl increased from 10.2 (T0) to 10.5 mm (T1); maxMO increased from 41.2 (T0) to 48 mm (T1). The proposed multidisciplinary assessment based on otolaryngological, gnathological, and radiological evaluation may be useful in the case of recurrent parotid swelling secondary to masseter muscle hypertrophy to plan an appropriate management with a removable neuromuscular orthosis.

  14. A new scleroglucan/borax hydrogel: swelling and drug release studies.

    Science.gov (United States)

    Coviello, Tommasina; Grassi, Mario; Palleschi, Antonio; Bocchinfuso, Gianfranco; Coluzzi, Gina; Banishoeib, Fateme; Alhaique, Franco

    2005-01-31

    The aim of the work was the characterization of a new polysaccharidic physical hydrogel, obtained from Scleroglucan (Sclg) and borax, following water uptake and dimension variations during the swelling process. Furthermore, the release of molecules of different size (Theophylline (TPH), Vitamin B12 (Vit. B12) and Myoglobin (MGB)) from the gel and from the dried system used as a matrix for tablets was studied. The increase of weight of the tablets with and without the loaded drugs was followed together with the relative variation of the dimensions. The dry matrix, in the form of tablets was capable, during the swelling process, to incorporate a relevant amount of solvent (ca. 20 g water/g dried matrix), without dissolving in the medium, leading to a surprisingly noticeable anisotropic swelling that can be correlated with a peculiar supramolecular structure of the system induced by compression. Obtained results indicate that the new hydrogel can be suitable for sustained drug release formulations. The delivery from the matrix is deeply dependent on the size of the tested model drugs. The experimental release data obtained from the gel were satisfactorily fitted by an appropriate theoretical approach and the relative drug diffusion coefficients in the hydrogel were estimated. The release profiles of TPH, Vit. B12 and MGB from the tablets have been analyzed in terms of a new mathematical approach that allows calculating of permeability values of the loaded drugs.

  15. Effect of Polyvinyl Acetate Stabilization on the Swelling-Shrinkage Properties of Expansive Soil

    Directory of Open Access Journals (Sweden)

    Jin Liu

    2017-01-01

    Full Text Available Polyvinyl acetate constitutes a class of polymers that can entirely dissolve in water to form a solution. In this study, polyvinyl acetate as a nontraditional chemical stabilizer was used in soil improvement. Laboratory tests were carried out to evaluate the effect of polyvinyl acetate on swelling-shrinkage properties of expansive soil. A series of shrink/swell tests were performed with adding polyvinyl acetate as amendment at a concentration 3 g/cm3 to four aggregate sizes in the range of 0–0.5 mm, 0.5–1 mm, 1-2 mm, and 2–5 mm and five concentrations 1.5 g/cm3, 3 g/cm3, 4.5 g/cm3, 6 g/cm3, and 9 g/cm3 to soils with aggregate size in the range of 0.5–1 mm for comparison of results with those of untreated soils. The results show that all the linear swelling ratio (LSWR and linear shrinkage ratio (LSHR values of the treated specimens decrease. SEM images and the test results indicate the achieved reduction in volume change of the soil tested using soil pore filling and particle encapsulation.

  16. Preparation and characterization of oil palm frond based cellulose hydrogel and its swelling properties

    Science.gov (United States)

    Selvakumaran, Nesha; Lazim, Mohd Azwani Shah bin Mat

    2016-11-01

    Malaysia is one of the largest producer of palm oil thus the quantity of biomass each year from this industry is very large. The oil palm frond from palm oil industry can be used as a source of cellulose which can be incorporated into hydrogel to be used as adsorbent. This research reported how to disperse 2 % cellulose in a `green-solution' prepared by using urea and sodium hydroxide. Polymerization is carried out between the monomers polyacrylamide and cellulose using microwave to form hydrogel. Hydrogel with 2 % cellulose have a swelling index of 1814 %. Meanwhile, zero hydrogel which is made with only polyacrylamide has swelling index of 15 %. Scanning electron microscope shows that cellulose hydrogel have a rough surface compared with zero hydrogel. This might attribute to the high swelling index for cellulose hydrogel compared with zero hydrogel. Meanwhile, FTIR shows that successful polymerization has occurred between polyacrylamide and cellulose with the characteristic band at 1657.99 cm-1 which is for N-H bond.

  17. Use of swelling clays to reduce permeability and its potential application to nuclear waste repository sealing

    International Nuclear Information System (INIS)

    Moore, D.E.; Morrow, C.A.; Byerlee, J.D.

    1982-01-01

    The injection of swelling-clay slurries into joints or faults at a deep-burial nuclear waste disposal site may result in signficant permeability reductions for the effective containment of radioactive wastes. In an experiment conducted to illustrate the permeability change accompanying clay swelling, a coarse stone with interconnected pore spaces was injected with a clay-electrolyte slurry, modelling the pressure-grouting of a fractured repository rock. Subsequently, solutions with lower electroylte concentrations were driven through the clay-filled stone, corresponding to migration of lower salinity ground-waters through the clay-grouted fracture. The initial injection procedure reduced the permeability of the stone from 1--10 darcies to 700 nanodarcies; the changes in solution composition decreased permeability by more than 2 additional orders of magnitude to 3 nanodarcies. For application at a nuclear waste repository, the electrolyte concentration of the injected clay slurry should be made higher than that of the ground-water in the host rock. Subesquent interaction of the ground-water with the clays would initiate swelling and create the additional, post-injection permeability reductions that may be important in preventing the escape of buried radioactive wastes. The measured permeability of the clay filling is considerably lower than that of cement tested for borehole plugging. Clays also have the advantage over cement and chemical grouts in that they are geologically stable at relatively low temperatures and have a high capacity for radionuclide adsorption

  18. MAPPING REMOVAL SWELLING CLAY SOILS IN THE AURES (N’GAOUS ALGERIA

    Directory of Open Access Journals (Sweden)

    Rahmani MOUNA

    2016-09-01

    Full Text Available The shrinkage and swelling phenomena of certain clay soils cause differential settlement manifested by disorders that affect mainly the individual frame. The objective of this research was to create a map related to these phenomena especially in the area of Algeria N’gaous (figure 1. The approach of the study is primarily based firstly on the interpretation of a geological map at a scale 1 : 50 000 and on the other part from existing literature and observations on a synthesis of a large number of geotechnical information to determine susceptibility to the phenomenon of clay or marl formations. This approach consisted in the establishment of a synthetic departmental mapping of these formations that have been identified from a hierarchy as to their susceptibility according to the shrinkage and swelling phenomenon. This classification was established on the basis of three quantifiable main features: the dominant lithology of formations, the mineralogical composition of their clay fraction (proportion of swelling minerals and geotechnical behavior (primarily assessed from the blue value and the plasticity index.

  19. "Caught by the Eye of Sound" - Epigastric Swelling due to Xiphisternal Tuberculosis.

    Science.gov (United States)

    Grover, Shabnam Bhandari; Arora, Sumit; Kumar, Amit; Grover, Hemal; Katyan, Amit; Nair, Deepthi Mohan

    2017-01-01

    Common causes of an epigastric mass include hepatomegaly, pancreatic pseudocyst and epigastric hernia, less common causes being carcinoma of the stomach or pancreas, whereas diseases of the sternum presenting as an epigastric swelling is extremely uncommon. We report a case of tubercular infection of the sternum located in the xiphoid process resulting in its presentation as an epigastric swelling. A 30-year-old immunocompetent woman with complaints of an epigastric swelling and undocumented pyrexia for four months was referred for sonographic evaluation with a clinical suspicion of an incompletely treated liver abscess. The patient was examined with ultrasound, sternal radiographs, CT and MRI. Ultrasound revealed a heterogeneous epigastric collection with linear echogenic components suggestive of bone fragments. These appearances suggested chronic infective osteomyelitis of the xiphoid process of the sternum. Lateral chest radiograph demonstrated lytic destruction of the xiphisternum. Tubercular etiology was considered and further evaluation with Multidetector Computed tomography (MDCT) and Magnetic Resonance Imaging (MRI) demonstrated erosive osteomyelitis of the xiphoid process with enhancing inflammation and collection in the adjoining soft tissue. Ultrasound-guided aspiration, PCR and Amplified Mycobacterium tuberculosis DNA test confirmed tubercular infection. We report a new case of osteo-articular tuberculosis localized to the xiphisternum, a rare clinical entity with an extremely unusual clinical presentation as an epigastric mass. The role of ultrasound in primary diagnosis and as an interventional diagnostic modality for guided aspiration is highlighted.

  20. Gaseous swelling of B4C and UO2 fuel: similarities and differences

    International Nuclear Information System (INIS)

    Evdokimov, I.; Khoruzhii, O.; Kourtchatov, S.; Likhanskii, V.; Matweev, L.

    2001-01-01

    A major factor limiting the resource of control rods (CRs) for WWER-1000 reactors is their radiation damage. Radiation induced embrittlement of the CRs cladding, core swelling and gaseous internal pressure in CRs result in mechanical core-cladding interaction. This work is devoted to the physical analysis of processes that control the structural changes in neutron absorber elements with B 4 C under irradiation in water reactors. Particularly, the analysis of mechanisms of the helium porosity formation in B 4 C is undertaken. In view of the deficiency of experimental data on the subject, a fruitful approach to the problem is a comparative analysis of the swelling mechanisms in B 4 C absorber and UO 2 fuel. Using this similarity a phenomenological model of fission gas behavior in boron carbide is proposed. The model predictions for radial profile of 10 B burnup under influence of thermal and epithermal neutrons are compared with experimental results. The main results show that despite the external similarity of the process of fission gas accumulation in UO 2 and in B 4 C, phenomenology of gaseous swelling is much different for the fuel and the CR core. The reason for that difference is the distinction of physical conditions in irradiated fuel and CR core