WorldWideScience

Sample records for corrosive industrial duct

  1. Corrosion in power industry

    International Nuclear Information System (INIS)

    Ventakeshwarlu, K.S.

    1979-01-01

    A brief account of the problem areas encountered as a result of corrosion in the electrical power industry including nuclear power industry is given and some of the measures contemplated and/or implemented to control corrosion are outlined. The corrosion problems in the steam generators and cladding tubes of the nuclear power plant have an added dimension of radioactivation which leads to contamination and radiation field. Importance of monitoring water quality and controlling water chemistry by addition of chemicals is emphasised. (M.G.B.)

  2. Corrosion in the oil industry

    Energy Technology Data Exchange (ETDEWEB)

    Brondel, D [Sedco Forex, Montrouge (France); Edwards, R [Schlumberger Well Services, Columbus, OH (United States); Hayman, A [Etudes et Productions Schlumberger, Clamart (France); Hill, D [Schlumberger Dowell, Tulsa, OK (United States); Mehta, S [Schlumberger Dowell, St. Austell (United Kingdom); Semerad, T [Mobil Oil Indonesia, Inc., Sumatra (Indonesia)

    1994-04-01

    Corrosion costs the oil industry billions of dollars a year, a fact that makes the role of the corrosion engineer an increasingly important one. Attention is paid to how corrosion affects every aspect of exploration and production, from offshore rigs to casing. Also the role of corrosion agents such as drilling and production fluids is reviewed. Methods of control and techniques to monitor corrosion are discussed, along with an explanation of the chemical causes of corrosion. 21 figs., 32 refs.

  3. Corrosion and anticorrosion. Industrial practice

    International Nuclear Information System (INIS)

    Beranger, G.; Mazille, H.

    2002-01-01

    This book comprises 14 chapters written with the collaboration of about 50 French experts of corrosion. It is complementary to another volume entitled 'corrosion of metals and alloys' and published by the same editor. This volume comprises two parts: part 1 presents the basic notions of corrosion phenomena, the properties of surfaces, the electrochemical properties of corrosion etc.. Part 2 describes the most frequent forms of corrosion encountered in industrial environments and corresponding to specific problems of protection: marine environment, atmospheric corrosion, galvanic corrosion, tribo-corrosion, stress corrosion etc.. The first 8 chapters (part 1) treat of the corrosion problems encountered in different industries and processes: oil and gas production, chemical industry, phosphoric acid industry, PWR-type power plants, corrosion of automobile vehicles, civil engineering and buildings, corrosion of biomaterials, non-destructive testing for the monitoring of corrosion. The other chapters (part 2) deal with anticorrosion and protective coatings and means: choice of materials, coatings and surface treatments, thick organic coatings and enamels, paints, corrosion inhibitors and cathodic protection. (J.S.)

  4. Corrosion management in nuclear industry

    International Nuclear Information System (INIS)

    Kamachi Mudali, U.

    2012-01-01

    Corrosion is a major degradation mechanism of metals and alloys which significantly affects the global economy with an average loss of 3.5% of GDP of several countries in many important industrial sectors including chemical, petrochemical, power, oil, refinery, fertilizer etc. The demand for higher efficiency and achieving name plate capacity, in addition to ever increasing temperatures, pressures and complexities in equipment geometry of industrial processes, necessitate utmost care in adopting appropriate corrosion management strategies in selecting, designing, fabricating and utilising various materials and coatings for engineering applications in industries. Corrosion control and prevention is an important focus area as the savings achieved from practicing corrosion control and prevention would bring significant benefits to the industry. Towards this, advanced corrosion management strategies starting from design, manufacturing, operation, maintenance, in-service inspection and online monitoring are essential. At the Indira Gandhi Centre for Atomic Research (IGCAR) strategic corrosion management efforts have been pursued in order to provide solutions to practical problems emerging in the plants, in addition to innovative efforts to provide insight into mechanism and understanding of corrosion of various engineering materials and coatings. In this presentation the author highlights how the nuclear industry benefited from the practical approach to successful corrosion management, particularly with respect to fast breeder reactor programme involving both reactor and associated reprocessing plants. (author)

  5. Duct corrosion in the ventilating air conditioning system for Main Control Room

    International Nuclear Information System (INIS)

    Yamada, Kohei; Kobayashi, Takashi; Minami, Akiko; Fukuba, Kazushi

    2014-01-01

    Higashidori Nuclear Power Station, start-of-operation in December 2005, is a relatively new plant. We decided to get original data of air duct condition to determine maintenance policy of air duct, because planned maintenance of air duct has never been done and the corrosion of air duct has occurred in other plant. In January 2014, we found a corrosion-hole at the downstream of the inlet damper in the ventilating air conditioning system for Main Control Room (MCR). We supposed that the cause of rapid corrosion is related to the characteristic environment of this site. (author)

  6. Corrosion characteristics of post-tensioning strands in ungrouted ducts : summary.

    Science.gov (United States)

    2011-01-01

    To prevent corrosion of post-tensioning strands, FDOT construction specifications currently require post-tensioning ducts to be grouted within seven calendar days of strand installation. This period challenges construction schedules on large projects...

  7. Corrosion engineering in nuclear power industry

    International Nuclear Information System (INIS)

    Prazak, M.; Tlamsa, J.; Jirousova, D.; Silber, K.

    1990-01-01

    Corrosion problems in nuclear power industry are discussed from the point of view of anticorrosion measures, whose aim is not only increasing the lifetime of the equipment but, first of all, securing ecological safety. A brief description is given of causes of corrosion damage that occurred at Czechoslovak nuclear power plants and which could have been prevented. These involve the corrosion of large-volume radioactive waste tanks made of the CSN 17247 steel and of waste piping of an ion exchange station made of the same material, a crack in a steam generator collector, contamination of primary circuit water with iron, and corrosion of CrNi corrosion-resistant steel in a spent fuel store. It is concluded that if a sufficient insight into the corrosion relationships exists and a reasonable volume of data is available concerning the corrosion state during the nuclear facility performance, the required safety can be achieved without adopting extremely costly anticorrosion measures. (Z.M.)

  8. Prevalence of bile duct cancer among printing industry workers in comparison with other industries.

    Science.gov (United States)

    Okamoto, Etsuji; Kikuchi, Kiyotaka; Endo, Ginji

    2013-01-01

    The aim of this study was to assess the risk of developing bile duct cancer among workers in the other printing industry in comparison with workers in all industries in general. Prevalence of bile duct cancer was compared between workers in the printing industry and age-standardized controls in all other industries using the claims database of the Japan Health Insurance Association, which insures workers of small-medium sized employers of all industries. Young (aged 30-49) male workers in the printing industry showed an elevated but insignificant standardized prevalence rate ratio (SPRR) for bile duct cancer in comparison with workers in all other industries (SPRR: 1.78; 95%CI: 0.63-5.00). The risk was higher for intrahepatic bile duct cancer but remained insignificant (SPRR: 3.03; 95%CI: 0.52-17.56). The sharply elevated risk of bile duct cancer observed among proof-printing workers of a printing factory in Osaka may not be generalizable to workers in the printing industry nationwide.

  9. Corrosion problems and solutions in oil refining and petrochemical industry

    CERN Document Server

    Groysman, Alec

    2017-01-01

    This book addresses corrosion problems and their solutions at facilities in the oil refining and petrochemical industry, including cooling water and boiler feed water units. Further, it describes and analyzes corrosion control actions, corrosion monitoring, and corrosion management. Corrosion problems are a perennial issue in the oil refining and petrochemical industry, as they lead to a deterioration of the functional properties of metallic equipment and harm the environment – both of which need to be protected for the sake of current and future generations. Accordingly, this book examines and analyzes typical and atypical corrosion failure cases and their prevention at refineries and petrochemical facilities, including problems with: pipelines, tanks, furnaces, distillation columns, absorbers, heat exchangers, and pumps. In addition, it describes naphthenic acid corrosion, stress corrosion cracking, hydrogen damages, sulfidic corrosion, microbiologically induced corrosion, erosion-corrosion, and corrosion...

  10. A Localised Corrosion Cell for Industrial Applications

    DEFF Research Database (Denmark)

    Andersen, A.; Hilbert, Lisbeth Rischel; Jansen, P.

    2003-01-01

    The LOCORR-CELL™ developed by FORCE TECHNOLOGY is an electrochemical cell for industrial applications estimating localised corrosion. The cell is constructed in a carbon steel casing for direct mounting into the system. It is based on an oxygen concentration element reflecting the interaction...... between the environment formed under a deposit or in a crevice. The essential feature of the method is that it reflects the influence of oxygen content, conductivity and temperature as well as the influence of corrosion inhibitors, MIC and other effects that have an effect on localised corrosion under...... deposits and in crevices. The measuring principle in the cell is based on measurements of the galvanic current flow between the steel anode covered by a porous glass frit and the surrounding steel casing. The current is measured by a zero-resistance circuit-instrument and the activity can be presented...

  11. Atmospheric corrosion of metals in industrial city environment

    Directory of Open Access Journals (Sweden)

    Elzbieta Kusmierek

    2015-06-01

    Full Text Available Atmospheric corrosion is a significant problem given destruction of various materials, especially metals. The corrosion investigation in the industrial city environment was carried out during one year exposure. Corrosion potential was determined using the potentiometric method. The highest effect of corrosion processes was observed during the winter season due to increased air pollution. Corrosion of samples pre-treated in tannic acid before the exposure was more difficult compared with the samples without pretreatment. The corrosion products determined with the SEM/EDS method prove that the most corrosive pollutants present in the industrial city air are SO2, CO2, chlorides and dust.

  12. Atmospheric corrosion of metals in industrial city environment.

    Science.gov (United States)

    Kusmierek, Elzbieta; Chrzescijanska, Ewa

    2015-06-01

    Atmospheric corrosion is a significant problem given destruction of various materials, especially metals. The corrosion investigation in the industrial city environment was carried out during one year exposure. Corrosion potential was determined using the potentiometric method. The highest effect of corrosion processes was observed during the winter season due to increased air pollution. Corrosion of samples pre-treated in tannic acid before the exposure was more difficult compared with the samples without pretreatment. The corrosion products determined with the SEM/EDS method prove that the most corrosive pollutants present in the industrial city air are SO2, CO2, chlorides and dust.

  13. PIPELINE CORROSION CONTROL IN OIL AND GAS INDUSTRY: A ...

    African Journals Online (AJOL)

    Corrosion in pipelines is one of the major challenges faced by oil and gas industries all over the world. This has made corrosion control or management a major factor to consider before setting up any industry that will transport products via pipelines. In this study the types of corrosion found on system 2A pipeline were; ...

  14. Atmospheric corrosion of metals in industrial city environment

    OpenAIRE

    Kusmierek, Elzbieta; Chrzescijanska, Ewa

    2015-01-01

    Atmospheric corrosion is a significant problem given destruction of various materials, especially metals. The corrosion investigation in the industrial city environment was carried out during one year exposure. Corrosion potential was determined using the potentiometric method. The highest effect of corrosion processes was observed during the winter season due to increased air pollution. Corrosion of samples pre-treated in tannic acid before the exposure was more difficult compared with the s...

  15. Corrosion and alteration of materials from the nuclear industry

    International Nuclear Information System (INIS)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Feron, D.; Guerin, Y.; Latge, C.; Limoge, Y.; Madic, C.; Santarini, G.; Seiler, J.M.; Vernaz, E.; Richet, C.

    2010-01-01

    The control of the corrosion phenomenon is of prime importance for the nuclear industry. The efficiency and the safety of facilities can be affected by this phenomenon. The nuclear industry has to face corrosion for a large variety of materials submitted to various environments. Metallic corrosion operates in the hot and aqueous environment of water reactors which represent the most common reactor type in the world. Progresses made in the control of the corrosion of the different components of these reactors allow to improve their safety. Corrosion is present in the facilities of the back-end of the fuel cycle as well (corrosion in acid environment in fuel reprocessing plants, corrosion of waste containers in disposal and storage facilities, etc). The future nuclear systems will widen even more the range of materials to be studied and the situations in which they will be placed (corrosion by liquid metals or by helium impurities). Very often, corrosion looks like a patchwork of particular cases in its description. The encountered corrosion problems and their study are presented in this book according to chapters representing the main sectors of the nuclear industry and classified with respect to their phenomenology. This monograph illustrates the researches in progress and presents some results of particular importance obtained recently. Content: 1 - Introduction: context, stakes and goals; definition of corrosion; a complex science; corrosion in the nuclear industry; 2 - corrosion in water reactors - phenomenology, mechanisms, remedies: A - uniform corrosion: mechanisms, uniform corrosion of fuel cladding, in-situ measurement of generalized corrosion rate by electrochemical methods, uniform corrosion of nickel alloys, characterization of the passive layer and growth mechanisms, the PACTOLE code - an integrating tool, influence of water chemistry on corrosion and contamination, radiolysis impact on uniform corrosion; B - stress corrosion: stress corrosion cracking

  16. The impact of corrosion on oil and gas industry

    International Nuclear Information System (INIS)

    Kermani, M.B.; Harrop, D.

    1995-01-01

    The impact of corrosion on the oil industry has been viewed in terms of its effect on both capital and operational expenditures (CAPEX and OPEX) and health, safety and the environment (HSE). To fight against the high cost and the impact of corrosion within the oil industry, an overview of topical research and engineering activities is presented. This covers corrosion and metallurgy issues related to drilling, production, transportation and refinery activities

  17. Corrosion Control in the Aerospace Industry

    Science.gov (United States)

    Calle, Luz Marina; Li, Wenyan; Buhrow, Jerry W.; Johnsey, Marissa N.

    2016-01-01

    Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. It is essential to detect corrosion when it occurs, and preferably at its early stage, so that action can be taken to avoid structural damage or loss of function. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it..

  18. Corrosion problems in nuclear power industry

    International Nuclear Information System (INIS)

    Flis, J.; Janik-Czachor, M.

    1980-01-01

    Characteristics were given of steels and alloys used in the PWR nuclear power plants and of water used in the primary and secondary systems. Corrosion damages of materials and installations were described. It was indicated that the damages were due mainly to stress corrosion cracking. Main preventive methods were listed. (author)

  19. PIPELINE CORROSION CONTROL IN OIL AND GAS INDUSTRY: A ...

    African Journals Online (AJOL)

    user

    protection technique as a method of controlling corrosion in oil and gas pipelines is effective and efficient when compared to ... In the field of crude oil production and associated engineering .... Industrial/Mechanical Systems, Joen Printing and.

  20. Microbiologically Influenced Corrosion (MIC) in the Oil and Gas Industry

    DEFF Research Database (Denmark)

    Skovhus, Torben Lund; Eckert, Rickard

    2015-01-01

    Microbiologically influenced corrosion (MIC) is a serious corrosion threat that impacts the operating integrity and reliability of assets in the oil and gas, maritime, power generation, and other industries. Yet MIC is also commonly misunderstood, leading to ineffective mitigation programs, wasted...... and implement improved mitigation strategies and thereby reduce operating risk. Our experts provide guidance in applying the latest state-of-the-art molecular microbiological methods (MMM) and industry standards to properly diagnose MIC in operating assets and on failed components. With this understanding, MIC...... can be effectively addressed as part of the overall Corrosion Management System (CMS)....

  1. Corrosion in the nuclear power industry

    International Nuclear Information System (INIS)

    Danko, J.C.

    1987-01-01

    This article reviews the major corrosion problems in light water reactors, the research on the corrosion mechanism(s), and the development of engineering solutions and their implementation. To understand the occurrence of corrosion problems, a brief historical perspective of the corrosion design basis of commercial light water reactors, boiling water, and pressurized water reactors is necessary. Although corrosion was considered in the plant designs, it was not viewed as a serious problem. This was based on the results of laboratory experiments and in-reactor tests that did not indicate any major corrosion problems with the materials selected for the plant construction. However, the laboratory tests did not necessarily reproduce the reactor operating conditions and the early in-reactor test did not fully represent the commercial reactor conditions in all cases, and, finally, the test times were indeed of short duration relative to the plant design lifetime of 40 years. Thus, the design basis for the materials selection was determined on the favorable but limited test data that were available, and corrosion limitations on component integrity were therefore not anticipated

  2. Corrosion issues in nuclear industry today

    International Nuclear Information System (INIS)

    Cattant, F.; Crusset, D.; Feron, D.

    2008-01-01

    In the context of global warming, nuclear energy is a carbon-free source of power and so is a meaningful option for energy production without CO 2 emissions. Currently, there are more than 440 commercial nuclear reactors, accounting for about 15% of electric power generation in the world, and there has not been a major accident in over 20 years. The world's fleet of nuclear power plants is, on average, more than 20 years old. Even though the design life of a nuclear power plant is typically 30 or 40 years, it is quite feasible that many nuclear power plants will be able to operate for longer than this. The re-emergence of nuclear power today is founded on the present generation of nuclear reactors meeting the demands of extended service life, ensuring the cost competitiveness of nuclear power and matching enhanced safety requirements. Nuclear power plant engineers should be able to demonstrate such integrity and reliability of their system materials and components as to enable nuclear power plants to operate beyond their initial design life. Effective waste management is another challenge for sustainable nuclear energy today; more precisely, a solution is needed for the management of high-level and long-lived intermediate-level radioactive waste over the very long term. Most nuclear countries are currently gathering the data needed to assess the feasibility of a deep geological waste repository, including the prediction of the behaviour of materials over several thousands of years. The extended service life of nuclear power plants and the need for permanent disposal for nuclear waste are today's key issues in the nuclear industry. We focus here on the major role that corrosion plays in these two factors, and on the French approaches to these two issues. (authors)

  3. A New Approach to Designing the S-Shaped Annular Duct for Industrial Centrifugal Compressor

    Directory of Open Access Journals (Sweden)

    Ivan Yurko

    2014-01-01

    Full Text Available The authors propose an analytical method for designing the inlet annular duct for an industrial centrifugal compressor using high-order Bezier curves. Using the design of experiments (DOE theory, the three-level full factorial design was developed for determination of influence of the dimensionless geometric parameters on the output criteria. Numerical research was carried out for determination of pressure loss coefficients and velocity swirl angles using the software system ANSYS CFX. Optimal values of the slope for a wide range of geometric parameters, allowing minimizing losses in the duct, have been found. The study has used modern computational fluid dynamics techniques to develop a generalized technique for future development of efficient variable inlet guide vane systems. Recommendations for design of the s-shaped annular duct for industrial centrifugal compressor have been given.

  4. Corrosion resistant alloy uses in the power industry

    International Nuclear Information System (INIS)

    Nickerson, J.L.; Hall, F.A.; Asphahani, A.I.

    1989-01-01

    Nickel-base alloys have been used as cost-effective measures in a variety of severely corrosive situations in pollution control units for coal-fired power plants. Cost effectiveness and practical answers to corrosion problems are illustrated (specifically the wallpaper concept/metallic lining technique). Numerous cases of successful use of HASTELLOY alloys in Flue Gas Desulfurization (FGD) systems and hazardous waste treatment incineration scrubber systems are listed. In this paper developments in nickel-base alloys and their use in FGD and other segments of the power industry are discussed. In the Ni-Cr-Mo-W alloy family, the C-22 alloy has the best resistance to localized corrosion in halide environments (chloride/fluoride-containing solutions). This alloy is also used effectively as a universal filler metal to weld less-resistant alloys were weld corrosion may be a problem. Field performance of this alloy in the power industry is described

  5. U.S. industry response to surry corrosion event

    International Nuclear Information System (INIS)

    Chexal, V.K.; Dietrich, E.B.; Torok, R.C.; Randall, G.A.; Shevde, V.C.; Horowitz, J.S.

    1990-01-01

    On December 9, 1986, a 460 mm (18 inch) diameter carbon steel elbow in the condensate system at Surry Unit-2 failed. The failure occurred as a consequence of thinning of the elbow by erosion-corrosion. Inspections revealed significant thinning of carbon steel sections at numerous locations in the condensate and feedwater piping of both Surry units. The subsequent discovery of thinning at other plants established erosion-corrosion as a generic issue for nuclear and fossil plants. To quickly resolve industry and regulatory concerns associated with single-phase erosion-corrosion, EPRI sought to: (1) find ways to determine where single phase erosion-corrosion is most likely to occur; (2) define accurate and low-cost inspection methods; and (3) identify techniques for preventing further pipe degradation. Erosion-corrosion programs have been conducted in a number of laboratories world-wide. The associated phenomena are complex and depend on the interrelationship of water temperature, water chemistry, component material, flow velocity and the geometry of the flow path (straight, bend, tee, etc.). EPRI supplemented existing data and developed technical products tailored for utility use on the erosion-corrosion issue. This paper describes the U.S. industry response to the Surry event and the related EPRI activities in the corrosion area

  6. EVALUATION OF CORROSION COST OF CRUDE OIL PROCESSING INDUSTRY

    Directory of Open Access Journals (Sweden)

    ADESANYA A.O.

    2012-08-01

    Full Text Available Crude oil production industry as the hub of Nigeria Economy is not immune to the global financial meltdown being experienced world over which have resulted in a continual fall of oil price. This has necessitated the need to reduce cost of production. One of the major costs of production is corrosion cost, hence, its evaluation. This research work outlined the basic principles of corrosion prevention, monitoring and inspection and attempted to describe ways in which these measures may be adopted in the context of oil production. A wide range of facilities are used in crude oil production making it difficult to evaluate precisely the extent of corrosion and its cost implication. In this study, cost of corrosion per barrel was determined and the annualized value of corrosion cost was also determined using the principles of engineering economy and results analyzed using descriptive statistics. The results showed that among the corrosion prevention methods identified, the use of chemical treatment gave the highest cost contribution (81% of the total cost of prevention while coating added 19%. Cleaning pigging and cathodic protection gave no cost. The contribution of corrosion maintenance methods are 60% for repairs and 40% for replacement. Also among the corrosion monitoring and inspection identified, NDT gave the highest cost contribution of 41% of the total cost, followed by coating survey (34%. Cathodic protection survey and crude analysis gives the lowest cost contribution of 19% and 6% respectively. Corrosion control cost per barrel was found to be 77 cent/barrel. The significance of this cost was not much due to high price of crude oil in the international market. But the effect of corrosion in crude oil processing takes its toll on crude oil production (i.e. deferment.

  7. EFFICIENCY IMPROVEMENT IN INDUSTRIAL BOILER BY FLUE GAS DUCT INSULATION

    OpenAIRE

    Sanjay H. Zala

    2017-01-01

    Now a days in industry major losses are find out so here we calculate these losses and find out efficiency of boiler. Boiler efficiency and energy losses from boiler are important parameter for any industry using boiler. In this work a detailed analysis was carried out for boiler at Anish Chemicals Bhavnagar. It is a combined water and fire tube boiler using biomass coal as fuel. Boiler efficiency calculated by direct method is in range of (78.5% to 81.6%). Major losses from boiler are heat ...

  8. Corrosion and alteration of materials from the nuclear industry; La Corrosion et l'alteration des materiaux du nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Feron, D.; Guerin, Y.; Latge, C.; Limoge, Y.; Madic, C.; Santarini, G.; Seiler, J.M.; Vernaz, E.; Richet, C.

    2010-07-01

    The control of the corrosion phenomenon is of prime importance for the nuclear industry. The efficiency and the safety of facilities can be affected by this phenomenon. The nuclear industry has to face corrosion for a large variety of materials submitted to various environments. Metallic corrosion operates in the hot and aqueous environment of water reactors which represent the most common reactor type in the world. Progresses made in the control of the corrosion of the different components of these reactors allow to improve their safety. Corrosion is present in the facilities of the back-end of the fuel cycle as well (corrosion in acid environment in fuel reprocessing plants, corrosion of waste containers in disposal and storage facilities, etc). The future nuclear systems will widen even more the range of materials to be studied and the situations in which they will be placed (corrosion by liquid metals or by helium impurities). Very often, corrosion looks like a patchwork of particular cases in its description. The encountered corrosion problems and their study are presented in this book according to chapters representing the main sectors of the nuclear industry and classified with respect to their phenomenology. This monograph illustrates the researches in progress and presents some results of particular importance obtained recently. Content: 1 - Introduction: context, stakes and goals; definition of corrosion; a complex science; corrosion in the nuclear industry; 2 - corrosion in water reactors - phenomenology, mechanisms, remedies: A - uniform corrosion: mechanisms, uniform corrosion of fuel cladding, in-situ measurement of generalized corrosion rate by electrochemical methods, uniform corrosion of nickel alloys, characterization of the passive layer and growth mechanisms, the PACTOLE code - an integrating tool, influence of water chemistry on corrosion and contamination, radiolysis impact on uniform corrosion; B - stress corrosion: stress corrosion cracking

  9. Development of sulfuric acid dew point corrosion resistant stainless steel for smokestacks and its ducts. Entotsu endoyo tairyusan roten fushoku stainless ko no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Sato, E.; Matsuhashi, R.; Koseki, T. (Nippon Steel Corp., Tokyo (Japan)); Ebara, R.; Nakamoto, H. (Mitsubishi Heavy Industries, Ltd., Tokyo (Japan))

    1993-05-20

    A new corrosion resistant steel was developed as a metal system lining material to prevent sulfuric acid dew point corrosion in smokestacks and ducts. SO3 in stack gas turns to sulfuric acid as a result of reacting with coexistent moisture in non-steady conditions during boiler actuation and shutdown when smokestack walls have low temperatures. When sulfuric acid thus generated contacts with metallic materials at temperatures lower than the sulfuric acid dew point temperature, sulfuric acid dew point corrosion occurs. During boiler steady operation, localized corrosion develops at clearance between salt deposits and the metallic materials. In order to improve the corrosion resistance, Mo, Cu and N were added in a reasonable range of amount. Entire surface corrosion resistance and local corrosion resistance were experimented in aqueous solutions simulating the smokestack environments to derive relational formulas with steel compositions. The new corrosion resistant steel met the the entire surface and local corrosion resistance requirements and was found economical. Low torsional velocity tensile and U-bend tests proved the steel satisfying the stress corrosion resistance requirement. Semi-automatic CO2 welding and shielded are welding provided good workability with no cracking, and impact strength and corrosion resistance in joints equivalent to those in the base material. 3 refs., 4 figs., 4 tabs.

  10. Corrosion, inspection and other problems associated with Heat exchangers in the heavy water industry

    International Nuclear Information System (INIS)

    Twigg, R.J.

    1980-01-01

    Corrosion, fabrication and inspection problems encountered in the heavy water industry Heat exchangers are discussed. Among the problems examined are erosion/corrosion of two pass exchangers, rolling of tubes, pitting, fretting and protection for long term storage. (auth)

  11. Anti-Corrosion Coating

    Science.gov (United States)

    1986-01-01

    SuperSpan RM 8000 is an anti-corrosion coating which effectively counteracts acid degradation, abrasive wear, and cracking in power industry facilities. It was developed by RM Industrial Products Company, Inc. with NERAC assistance. It had previously been necessary to shut down plants to repair or replace corroded duct-work in coal burning utilities. NASA-developed technology was especially useful in areas relating to thermoconductivity of carbon steel and the bonding characteristics of polymers. The product has sold well.

  12. Monitoring and evaluation of duct emission and stationary sources of ceramic industries by SR-TXRF

    International Nuclear Information System (INIS)

    Moreira, Silvana; Fonseca, Roney Jose; Vives, Ana Elisa Sirito de

    2009-01-01

    The aim of this study was to monitor and evaluate the emission of metals from ducts and stationary sources in ceramic industries in the region of the ceramic centre of Santa Gertrudes in the state of Sao Paulo. There has been a growth of this industrial sector in recent years. This reflected upon the environment in this region which is responsible for 60% of ceramic tile floor production. From 2005 to 2006, samples of gases emitted by several ceramic companies in that region were collected. Metal concentration was determined through X-ray Fluorescence by Total Reflection with Synchrotron Radiation (SR-TXRF) technique. The analyses were carried out in the National Laboratory of Synchrotron Light (NLSL) and used a polychromatic beam of light to stimulate the samples and a hyper pure Germanic detector for the characteristic X-ray detection. The following elements were detected: Al, S, Cl, K, Ca, Fe, Cr, Mn, Ni, Cu, Zn and Pb. High concentrations of elements such as Chromium, Nickel and Lead were observed in the samples analyzed which presented values of concentrations higher than the ones permitted by legislation. (author)

  13. Monitoring and evaluation of duct emission and stationary sources of ceramic industries by SR-TXRF

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana; Fonseca, Roney Jose, E-mail: silvana@fec.unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo; Vives, Ana Elisa Sirito de, E-mail: aesvives@unimep.b [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo

    2009-07-01

    The aim of this study was to monitor and evaluate the emission of metals from ducts and stationary sources in ceramic industries in the region of the ceramic centre of Santa Gertrudes in the state of Sao Paulo. There has been a growth of this industrial sector in recent years. This reflected upon the environment in this region which is responsible for 60% of ceramic tile floor production. From 2005 to 2006, samples of gases emitted by several ceramic companies in that region were collected. Metal concentration was determined through X-ray Fluorescence by Total Reflection with Synchrotron Radiation (SR-TXRF) technique. The analyses were carried out in the National Laboratory of Synchrotron Light (NLSL) and used a polychromatic beam of light to stimulate the samples and a hyper pure Germanic detector for the characteristic X-ray detection. The following elements were detected: Al, S, Cl, K, Ca, Fe, Cr, Mn, Ni, Cu, Zn and Pb. High concentrations of elements such as Chromium, Nickel and Lead were observed in the samples analyzed which presented values of concentrations higher than the ones permitted by legislation. (author)

  14. Corrosion

    Science.gov (United States)

    Slabaugh, W. H.

    1974-01-01

    Presents some materials for use in demonstration and experimentation of corrosion processes, including corrosion stimulation and inhibition. Indicates that basic concepts of electrochemistry, crystal structure, and kinetics can be extended to practical chemistry through corrosion explanation. (CC)

  15. Corrosion problems and its prevention in nuclear industries

    International Nuclear Information System (INIS)

    Sakae, Yukio; Susukida, Hiroshi; Kowaka, Masamichi; Fujikawa, Hisao.

    1979-01-01

    29 nuclear power plants with 2.56 million kW output are expected to be in operation by 1985 in Japan. The main problems of corrosion in the nuclear reactors in operation at present and promising for the future are as follows: corrosion, denting and stress corrosion cracking in the steam generator tubes for PWRs, stress corrosion cracking in SUS pipings for BWRs, sodium corrosion and mass transfer in FBRs, high temperature gas corrosion in HTGRs, and interaction between coolant, blanket material and structural material in nuclear fusion reactors. In LWRs, the countermeasures based on the experiences in actual plants and the results of simulation tests have attained the good results. Various monitoring systems and the techniques for in-service inspection and preservice inspection have accomplished astonishing progress. These contributed largely to establish the reliability of nuclear power plants. The cases of troubles in primary and secondary systems, the experiences of the corrosion of steam generator tubes and the countermeasures, and the denting troubles occurred in USA and the trend of countermeasures in PWRs, the cases of stress corrosion cracking in SUS 304 and 316 pipings for BWRs, and the problems of various future reactors are described. Unexpected troubles often occur in practical plants of large capacity, therefore the method of predicting tests must be established, and the monitoring of safety must be thorough. (Kako, I.)

  16. Study of corrosion-erosion behaviour of stainless alloys in industrial phosphoric acid medium

    International Nuclear Information System (INIS)

    Guenbour, Abdellah; Hajji, Mohamed-Adil; Jallouli, El Miloudi; Bachir, Ali Ben

    2006-01-01

    The corrosion and corrosion-abrasion resistance of some stainless steels in industrial phosphoric acid 30% P 2 O 5 has been studied using electrochemical techniques. The corrosion rate of materials increases with the increase of temperature. Alloys which contain chromium, molybdenum and nitrogen in sufficient quantities present the best behaviour. In the abrasion-corrosion conditions, the experimental device set up allowed to follow continually samples electrochemical behaviour. Under dynamic conditions and without solid particles, the increase of acid projection speed has no effect on the alloys corrosion behaviour. The adding of abrasive leads to a general increase of corrosion rate and to a decrease of material resistance. Under these conditions, materials attack is controlled by synergistic effect between the abrasion and the impurities. The cast 30% Cr shows good resistance according to his high chromium content

  17. Study of corrosion-erosion behaviour of stainless alloys in industrial phosphoric acid medium

    Energy Technology Data Exchange (ETDEWEB)

    Guenbour, Abdellah [Laboratory of Electrochemistry-Corrosion, Av. Ibn Batouta, BP1014-Faculty of Science, Rabat (Morocco)]. E-mail: guenbour@fsr.ac.ma; Hajji, Mohamed-Adil [Group Corrosion and Protection of Materials, ENIM, Rabat (Morocco); Jallouli, El Miloudi [Group Corrosion and Protection of Materials, ENIM, Rabat (Morocco); Bachir, Ali Ben [Laboratory of Electrochemistry-Corrosion, Av. Ibn Batouta, BP1014-Faculty of Science, Rabat (Morocco)

    2006-12-30

    The corrosion and corrosion-abrasion resistance of some stainless steels in industrial phosphoric acid 30% P{sub 2}O{sub 5} has been studied using electrochemical techniques. The corrosion rate of materials increases with the increase of temperature. Alloys which contain chromium, molybdenum and nitrogen in sufficient quantities present the best behaviour. In the abrasion-corrosion conditions, the experimental device set up allowed to follow continually samples electrochemical behaviour. Under dynamic conditions and without solid particles, the increase of acid projection speed has no effect on the alloys corrosion behaviour. The adding of abrasive leads to a general increase of corrosion rate and to a decrease of material resistance. Under these conditions, materials attack is controlled by synergistic effect between the abrasion and the impurities. The cast 30% Cr shows good resistance according to his high chromium content.

  18. Radiographic evaluation of corrosion/erosion failures in pressure vessels and pipings in fertilizer industry

    International Nuclear Information System (INIS)

    Sinha, G.S.; Sahay, K.N.; Sundaram, K.V.; Banerji, K.C.

    1977-01-01

    The uses of radiography in combating the corrosion/erosion failures of pressure equipments used in the fertilizer industry are highlighted. Premature failures in fertilizer plants have proved to be very costly. One of the principal agencies responsible for such failures in process industry is corrosion/erosion. Radiography, when supplemented with other NDT-techniques, has been found to be ideal and highly useful method for on-stream inspection and evaluation of corrosion/erosion failures of pressure vessels and pipings. Three case-histories have been presented to illustrate the importance of radiography. (author)

  19. Testing and prediction of erosion-corrosion for corrosion resistant alloys used in the oil and gas production industry

    Science.gov (United States)

    Rincon, Hernan E.

    The corrosion behavior of CRAs has been thoroughly investigated and documented in the public literature by many researchers; however, little work has been done to investigate erosion-corrosion of such alloys. When sand particles are entrained in the flow, the degradation mechanism is different from that observed for sand-free corrosive environment. There is a need in the oil and gas industry to define safe service limits for utilization of such materials. The effects of flow conditions, sand rate, pH and temperature on the erosion-corrosion of CRAs were widely studied. An extensive experimental work was conducted using scratch tests and flow loop tests using several experimental techniques. At high erosivity conditions, a synergistic effect between erosion and corrosion was observed. Under the high sand rate conditions tested, erosivity is severe enough to damage the passive layer protecting the CRA thereby enhancing the corrosion rate. In most cases there is likely a competition between the rates of protective film removal due to mechanical erosion and protective film healing. Synergism occurs for each of the three alloys examined (13Cr and Super13Cr and 22Cr); however, the degree of synergism is quite different for the three alloys and may not be significant for 22Cr for field conditions where erosivities are typically much lower that those occurring in the small bore loop used in this research. Predictions of the corrosion component of erosion-corrosion based on scratch test data compared reasonably well to test results from flow loops for the three CRAs at high erosivity conditions. Second order behavior appears to be an appropriate and useful model for representing the repassivation process of CRAs. A framework for a procedure to predict penetration rates for erosion-corrosion conditions was developed based on the second order model behavior observed for the re-healing process of the passive film of CRAs and on computational fluid dynamics (CFD) simulations

  20. Corrosion protection by organic coatings in gas and oil industry

    International Nuclear Information System (INIS)

    Hussain, A.

    2008-01-01

    The drive to improve performance of coatings as protection against corrosion for automotive, aerospace and oil and gas industries is a never-ending story. Surface preparation is the most important single factor when a substrate surface e.g. steel is to be protected with a coating. This implies an extremely accurate and reliable characterisation of the substrate-surface prior to coating process and the investigation of polymeric coating materials. In order to have a durable adhesive bonding between the polymeric coating materials and the substrate i.e. to ensure prolonged life time and fewer maintenance intervals of coated products, a pre-treatment of the substrate is required in many cases. Sand blasting, corona /plasma pre.treatment of the substrate and the use of coupling agents like organo silanes are well accepted recent methods. Advanced surface analytical techniques like ESCA and TOFSIMS are proving to be extremely helpful in the chemical characterisation of the substrate surface. Contamination e.g. fat residues, tensides etc. on the substrate is one of the most serious enemies of adhesive bonding and the above mentioned techniques are playing a vital role in combating the enemy. Modern thermal analytical methods have made tremendous contribution to the development and quality control of high-performance polymeric coatings. MDSC, DMA and DETA are proving to be very useful tools for the characterisation of high-performance coating materials. An in-depth understanding of the structure-property relationship of these materials, predominantly epoxy and polyurethane coating systems, is a pre-requisite for their successful application and subsequent Quality Control. (author)

  1. Microbiological corrosion of ASTM SA105 carbon steel pipe for industrial fire water usage

    Science.gov (United States)

    Chidambaram, S.; Ashok, K.; Karthik, V.; Venkatakrishnan, P. G.

    2018-02-01

    The large number of metallic systems developed for last few decades against both general uniform corrosion and localized corrosion. Among all microbiological induced corrosion (MIC) is attractive, multidisciplinary and complex in nature. Many chemical processing industries utilizes fresh water for fire service to nullify major/minor fire. One such fire water service line pipe attacked by micro-organisms leads to leakage which is industrially important from safety point of view. Also large numbers of leakage reported in similar fire water service of nearby food processing plant, paper & pulp plant, steel plant, electricity board etc…In present investigation one such industrial fire water service line failure analysis of carbon steel line pipe was analyzed to determine the cause of failure. The water sample subjected to various chemical and bacterial analyses. Turbidity, pH, calcium hardness, free chlorine, oxidation reduction potential, fungi, yeasts, sulphide reducing bacteria (SRB) and total bacteria (TB) were measured on water sample analysis. The corrosion rate was measured on steel samples and corrosion coupon measurements were installed in fire water for validating non flow assisted localized corrosion. The sulphide reducing bacteria (SRB) presents in fire water causes a localized micro biological corrosion attack of line pipe.

  2. Corrosion products of reinforcement in concrete in marine and industrial environments

    International Nuclear Information System (INIS)

    Vera, R.; Villarroel, M.; Carvajal, A.M.; Vera, E.; Ortiz, C.

    2009-01-01

    The corrosion products formed on embedded steel in concrete under simulated marine and industrial conditions and natural marine environment were studied. A 0.50 water/cement ratio concrete was used and 3.5% NaCl and 180 g L -1 of H 2 SO 4 with 70 ppm of chloride ions solutions were used to simulate the synthetic medium. The initial electrochemical variables of the steel and pH, chlorides and sulfates profiles were measured according to the concrete depth. The morphology of the corrosive attack was determined via scanning electron microscopy (SEM), and the composition of the corrosion products was determined using an X-ray analyzer and an X-ray diffractometer (XRD). The protective power of the corrosion products was evaluated through anodic polarization curves in a saturated Ca(OH) 2 solution. The results from XRD and SEM show that all the resulting corrosion products correspond to lepidocrocite, goethite and magnetite mixtures; moreover, akaganeite was also identified under natural and simulated marine environments. Siderite was only detected in samples exposed to a natural marine environment. Concerning the protective nature of the corrosion products, these show lower performance in a simulated industrial environment, where the corrosion rate of the steel is up to 1.48 μm year -1

  3. Corrosion products of reinforcement in concrete in marine and industrial environments

    Energy Technology Data Exchange (ETDEWEB)

    Vera, R. [Instituto de Quimica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2950, Casilla 4059, Valparaiso (Chile)], E-mail: rvera@ucv.cl; Villarroel, M. [Instituto de Quimica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2950, Casilla 4059, Valparaiso (Chile); Carvajal, A.M. [Facultad de Ingenieria, Escuela de Construccion Civil, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, Macul, Santiago (Chile); Vera, E.; Ortiz, C. [Universidad Pedagogica y Tecnologica de Colombia, Avenida Central Norte, Km 2, Tunja (Colombia)

    2009-03-15

    The corrosion products formed on embedded steel in concrete under simulated marine and industrial conditions and natural marine environment were studied. A 0.50 water/cement ratio concrete was used and 3.5% NaCl and 180 g L{sup -1} of H{sub 2}SO{sub 4} with 70 ppm of chloride ions solutions were used to simulate the synthetic medium. The initial electrochemical variables of the steel and pH, chlorides and sulfates profiles were measured according to the concrete depth. The morphology of the corrosive attack was determined via scanning electron microscopy (SEM), and the composition of the corrosion products was determined using an X-ray analyzer and an X-ray diffractometer (XRD). The protective power of the corrosion products was evaluated through anodic polarization curves in a saturated Ca(OH){sub 2} solution. The results from XRD and SEM show that all the resulting corrosion products correspond to lepidocrocite, goethite and magnetite mixtures; moreover, akaganeite was also identified under natural and simulated marine environments. Siderite was only detected in samples exposed to a natural marine environment. Concerning the protective nature of the corrosion products, these show lower performance in a simulated industrial environment, where the corrosion rate of the steel is up to 1.48 {mu}m year{sup -1}.

  4. Technology development by the U.S. industry to resolve erosion-corrosion

    International Nuclear Information System (INIS)

    Chexal, B.; Dietrich, N.; Horowitz, J.; Layman, W.; Randall, G.; Shevde, V.

    1990-01-01

    Erosion-corrosion is a flow-accelerated corrosion process that leads to wall thinning (metal loss) of steel piping exposed to flowing water or wet steam. The rate of metal loss depends on a complex interplay of several parameters. These parameters include water chemistry, material composition, and hydrodynamics. Erosion-corrosion of plant piping can lead to costly outages and repairs, and can raise concerns about plant reliability and safety. Pipe wall degradation rates as high as 1.5 mm/year have occurred, resulting in pipe ruptures at both fossil and nuclear plants. The Nuclear Management and Resource Council (NUMARC) and EPRI have developed inspection planning methods and tools to help utilities identify areas of piping that might undergo erosion-corrosion. These tools provide utilities with the ability to predict wall thinning and to assess various remedial options. This allows utilities to plan and perform inspections, and to correct problems found during inspection. The U.S. electric power industry has developed the knowledge and the tools needed to protect against erosion-corrosion, and utilities have implemented erosion-corrosion monitoring programs. This paper describes EPRI's technical developments that support the utilities in determining where to inspect for erosion-corrosion. 15 refs, 7 figs

  5. Advances in the application of molecular microbiological methods in the oil and gas industry and links to microbiologically influenced corrosion

    DEFF Research Database (Denmark)

    Eckert, Rickard; Skovhus, Torben Lund

    2018-01-01

    While the oil and gas industry has witnessed increased applications of molecular microbiological methods (MMMs) for diagnosing and managing microbiologically influenced corrosion (MIC) in the past decade, the process for establishing clear links between microbiological conditions and corrosion...... mechanisms is still emerging. Different MMMs provide various types of information about microbial diversity, abundance, activity and function, all of which are quite different from the culture-based results that are familiar to oil and gas industry corrosion professionals. In addition, a multidisciplinary...

  6. Corrosion of Selected Materials in Boiling Sulfuric Acid for the Nuclear Power Industries

    International Nuclear Information System (INIS)

    Kim, Dong Jin; Lee, Han Hee; Kwon, Hyuk Chul; Kim, Hong Pyo; Hwang, Seong Sik

    2007-01-01

    Iodine sulfur (IS) process is one of the promising processes for a hydrogen production by using a high temperature heat generated by a very high temperature gas cooled reactor(VHTR) in the nuclear power industries. Even though the IS process is very efficient for a hydrogen production and it is not accompanied by a carbon dioxide evolution, the highly corrosive environment of the process limits its application in the industry. Corrosion tests of selected materials were performed in sulfuric acid to select appropriate materials compatible with the IS process. The materials used in this work were Fe-Cr alloys, Fe-Ni-Cr alloys, Fe-Si alloys, Ni base alloys, Ta, Ti, Zr, SiC, Fe-Si, etc. The test environments were 50 wt% sulfuric acid at 120 .deg. C and 98 wt% at 320 .deg. C. Corrosion rates were measured by using a weight change after an immersion. The surface morphologies and cross sectional areas of the corroded materials were examined by using SEM equipped with EDS. Corrosion behaviors of the materials were discussed in terms of the chemical composition of the materials, a weight loss, the corrosion morphology, the precipitates in the microstructure and the surface layer composition

  7. Corrosion behavior of metals and alloys in marine-industrial environment

    Directory of Open Access Journals (Sweden)

    Mariappan Natesan, Subbiah Selvaraj, Tharmakkannu Manickam and Gopalachari Venkatachari

    2008-01-01

    Full Text Available This work deals with atmospheric corrosion to assess the degrading effects of air pollutants on ferrous and non-ferrous metals and alloys, which are mostly used as engineering materials. An exposure study was conducted in the Tuticorin port area located on the east coast of South India, in the Gulf of Mannar with Sri Lanka to the southeast. Common engineering materials, namely mild steel, galvanized iron, Zn, Al, Cu and Cu–Zn alloys (Cu–27Zn, Cu–30Zn and Cu–37Zn, were used in the investigation. The site was chosen where the metals are exposed to marine and industrial atmospheres. Seasonal 1 to 12 month corrosion losses of these metals and alloys were determined by a weight loss method. The weight losses showed strong corrosion of mild steel, galvanized iron, Cu and Zn and minor effect on Al and Cu–Zn alloys. Linear regression analysis was conducted to study the mechanism of corrosion. The composition of corrosion products formed on the metal surfaces was identified by x-ray diffraction and Fourier transform infrared spectroscopy.

  8. Influence of Rust Permeability on Corrosion of E690 Steel in Industrial and Non-industrial Marine Splash Zones

    Science.gov (United States)

    Chen, Mindong; Pang, Kun; Liu, Zhiyong; Wu, Junsheng; Li, Xiaogang

    2018-05-01

    The corrosion behaviour of E690 steel in industrial and non-industrial marine splash environments was studied by environmental testing, morphology analysis, electrochemical measurements, and scanning Kelvin probe microscopy. Chloride and sulphide anions were found to diffuse across the rust layer following the evaporation of seawater splashed on the steel's surface. The cation-selective permeability of the rust layer resulted in an anion concentration gradient across the rust layer, which was more significant in the presence of sulphur dioxide. In addition, sulphur dioxide enhanced the formation of α-FeOOH, which led to the formation of distinct anode and cathode areas at the rust/steel interface.

  9. The use of computers for chemistry and corrosion monitoring in the nuclear power industry

    International Nuclear Information System (INIS)

    Eber, K.

    1986-01-01

    Corrosion of steam generators in the nuclear power industry has caused increasingly expensive maintenance work during refueling outages. To assist in the control and monitoring of this problem, Northeast Utilities has developed computer programs for tracking steam generator water chemistry and steam generator eddy current inspection data. These programs have allowed detailed analytical studies to be performed which would have been extremely difficult without the use of computers. The paper discusses the capabilities and uses of a chemistry data management system. An example analysis of steam generator chemistry during plant startup is presented. The corrosion monitoring capabilities of several eddy current data analysis programs are also discussed. It is demonstrated how these programs allow a detailed analysis of the effects of a chemical cleaning operation to remove sludge from the steam generators. Applications of these analytical methods to other industries is also discussed

  10. Monitoring wear and corrosion in industrial machines and systems: A radiation tool

    International Nuclear Information System (INIS)

    Konstantinov, I.O.; Zatolokin, B.V.

    1994-01-01

    Industrial equipment and machines, transport systems, nuclear and conventional power plants, pipelines, and other materials is substantially influenced by degradation processes such as wear and corrosion. For safety and economic reasons, appropriately monitoring the damage could prevent dangerous accidents. When the surfaces of machine parts under investigation are not easy to reach or are concealed by overlying structures, nuclear methods have become powerful tools for examination. They include X-ray radiography, neutron radiography, and a technique known as thin layer activation (TLA)

  11. Proceedings: On-line monitoring of corrosion an water chemistry for the electric power utility industry: An EPRI workshop held during the 12th International Corrosion Congress

    International Nuclear Information System (INIS)

    Licina, G.

    1994-03-01

    A two-day EPRI workshop on On-line Monitoring of Corrosion and Water Chemistry for the Electric Power Utility Industry included discussions on a variety of methods for the online monitoring of corrosion and water chemistry in a power plant environment. The workshop was held September 22 and 23, 1993 in Houston, Texas, as a part of the 12th International Corrosion Congress sponsored by NACE International. Methods in various stages of development, from laboratory demonstrations to in-plant monitoring, were presented by authors from all over the world. Recent developments in corrosion monitoring and the detection of specific chemical species in power plant environments have utilized a variety of electrochemical methods (both AC and DC), electrical resistance techniques, and potential drop techniques to evaluate crack extension. Other approaches, such as Raman spectroscopy of corroding surfaces, Specific ion detectors, and X-ray fluorescence and ion chromatography to analyze corrosion products have been demonstrated in the laboratory. Techniques that were described in the twenty-three technical papers included: Electrochemical noise, Electrical resistance, Field signature method, Linear polarization resistance, Neutron activation, Corrosion potential monitoring, Electrochemical detection of biofilm activity, Analysis of corrosion products by X-ray fluorescence, Potential drop method for assessing environmentally assisted crack growth, Harmonic impedance spectroscopy, Contact electric resistance, Conductivity and hydrogen sensors, Solid state methods for tracking oxygen and pH, and Raman spectroscopy. Individual papers are indexed separately

  12. A case of occupational bile duct carcinoma following exposure to a chlorinated organic solvent in the printing industry that was recognized as a work-related accident.

    Science.gov (United States)

    Fujiyoshi, Toshihisa; Hijioka, Susumu; Imaoka, Hiroshi; Hara, Kazuo; Mizuno, Nobumasa; Tanaka, Tsutomu; Tajika, Masahiro; Shimizu, Yasuhiro; Niwa, Yasumasa; Yamao, Kenji

    2014-12-01

    A man in his 40s presented with liver dysfunction on a screening examination. He was working in the printing industry and had been exposed to a chlorinated organic solvent for 12 years from the age of 20. Detailed examination revealed hilar bile duct cancer; proton radiotherapy was initiated. About three years after completing the proton radiotherapy, recurrence was suspected in hepatic hilar lymph nodes on radiological examination, and he was referred to our hospital. Endoscopic ultrasound-guided fine-needle aspiration of hepatic hilar lymph nodes revealed adenocarcinoma, and systemic chemotherapy was started. Two years later, the lymph nodes showed tumor regrowth, and surgical lymph node resection was performed. To date, 20 months after resection, no recurrence has been identified. We report a case of bile duct carcinoma that was recognized as a work-related accident in an individual working in the printing industry.

  13. Chemical Industry Corrosion Management: A Comprehensive Information System (ASSET 2). Final Report

    Energy Technology Data Exchange (ETDEWEB)

    John, Randy C. [Shell Global Solutions, Houston, TX (United States); Young, Arthur L. [Humberside Solutions, Toronto, ON (Canada); Pelton, Arthur D. [CRCT, Ecole Polytechnique de Montreal, Quebec (Canada); Thompson, William T. [Royal Military College of Canada, Kingston, ON (Canada); Wright, Ian G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2008-10-10

    The research sponsored by this project has greatly expanded the ASSET corrosion prediction software system to produce a world-class technology to assess and predict engineering corrosion of metals and alloys corroding by exposure to hot gases. The effort included corrosion data compilation from numerous industrial sources and data generation at Shell Oak Ridge National Laboratory and several other companies for selected conditions. These data were organized into groupings representing various combinations of commercially available alloys and corrosion by various mechanisms after acceptance via a critical screening process to ensure the data were for alloys and conditions, which were adequately well defined, and of sufficient repeatability. ASSET is the largest and most capable, publicly-available technology in the field of corrosion assessment and prediction for alloys corroding by high temperature processes in chemical plants, hydrogen production, energy conversion processes, petroleum refining, power generation, fuels production and pulp/paper processes. The problems addressed by ASSET are: determination of the likely dominant corrosion mechanism based upon information available to the chemical engineers designing and/or operating various processes and prediction of engineering metal losses and lifetimes of commercial alloys used to build structural components. These assessments consider exposure conditions (metal temperatures, gas compositions and pressures), alloy compositions and exposure times. Results of the assessments are determination of the likely dominant corrosion mechanism and prediction of the loss of metal/alloy thickness as a function of time, temperature, gas composition and gas pressure. The uses of these corrosion mechanism assessments and metal loss predictions are that the degradation of processing equipment can be managed for the first time in a way which supports efforts to reduce energy consumption, ensure structural integrity of equipment

  14. Ultrasonic Measurement of Erosion/corrosion Rates in Industrial Piping Systems

    Science.gov (United States)

    Sinclair, A. N.; Safavi, V.; Honarvar, F.

    2011-06-01

    Industrial piping systems that carry aggressive corrosion or erosion agents may suffer from a gradual wall thickness reduction that eventually threatens pipe integrity. Thinning rates could be estimated from the very small change in wall thickness values measured by conventional ultrasound over a time span of at least a few months. However, measurements performed over shorter time spans would yield no useful information—minor signal distortions originating from grain noise and ultrasonic equipment imperfections prevent a meaningful estimate of the minuscule reduction in echo travel time. Using a Model-Based Estimation (MBE) technique, a signal processing scheme has been developed that enables the echo signals from the pipe wall to be separated from the noise. This was implemented in a laboratory experimental program, featuring accelerated erosion/corrosion on the inner wall of a test pipe. The result was a reduction in the uncertainty in the wall thinning rate by a factor of four. This improvement enables a more rapid response by system operators to a change in plant conditions that could pose a pipe integrity problem. It also enables a rapid evaluation of the effectiveness of new corrosion inhibiting agents under plant operating conditions.

  15. Effect of Ni on the corrosion resistance of bridge steel in a simulated hot and humid coastal-industrial atmosphere

    Science.gov (United States)

    Li, Dong-liang; Fu, Gui-qin; Zhu, Miao-yong; Li, Qing; Yin, Cheng-xiang

    2018-03-01

    The corrosion resistance of weathering bridge steels containing conventional contents of Ni (0.20wt%, 0.42wt%, 1.50wt%) and a higher content of Ni (3.55wt%) in a simulated hot and humid coastal-industrial atmosphere was investigated by corrosion depth loss, scanning electron microscopy-energy-dispersive X-ray spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical methods. The results showed that, with increasing Ni content, the mechanical properties of the bridge steel were markedly improved, the welding parameters were satisfactory at room temperature, and the corrosion resistance was enhanced. When the Ni content was low (≤0.42wt%), the crystallization process of the corrosion products was substantially promoted, enhancing the stability of the rust layer. When the Ni content was higher ( 3.55wt%), the corrosion reaction of the steel quickly reached a balance, because the initial rapid corrosion induced the formation of a protective rust layer in the early stage. Simultaneously, NiO and NiFe2O2 were generated in large quantities; they not only formed a stable, compact, and continuous oxide protective layer, but also strongly inhibited the transformation process of the corrosion products. This inhibition reduced the structural changes in the rust layer, thereby enhancing the protection. However, when the Ni content ranged from 0.42wt% to 1.50wt%, the corrosion resistance of the bridge steel increased only slightly.

  16. Biocide and corrosion inhibition use in the oil and gas industry: Effectiveness and potential environmental impacts

    International Nuclear Information System (INIS)

    Brandon, D.M.; Fillo, J.P.; Morris, A.E.; Evans, J.M.

    1995-01-01

    Treatment chemicals are used in all facets of the natural gas industry (NGI) from well development through transmission and storage of natural gas. The multitude of chemicals used, combined with the dozens of chemical manufacturers and/or suppliers has lead to the availability of hundreds of possible chemical products. Because of the widespread use of chemical products and their numerous sources, the NGI needs access to consistent data regarding their effectiveness and potential environmental impacts. The objective of this work was to evaluate the effectiveness and potential environmental impacts of, chemical products used in the NGI. This assessment was initially focused on biocides and corrosion inhibitors and their use in the gas production, storage and transmission facilities, The overall approach was obtain the necessary data on chemical use and effectiveness directly from the oil and gas industry, supplemented with data/information obtained from the published literature. Five case histories of chemical use were documented and evaluated to assess the effectiveness of these chemicals. Potential environmental impacts were addressed by performing a screening environmental assessment on the use of glutaraldehyde, a widely used biocide. Prototype discharge scenarios were formulated and modeled to evaluate potential impacts to groundwater and surface water. The paper describes the basis for the study, provides an overview of chemical use with a focus on biocides and corrosion inhibitors, describes and assesses the specific uses of chemicals, and presents the results of the environmental assessment. It was found that various chemicals can be effective in treating microbiologically influenced corrosion and souring, but that the effectiveness of specific chemicals is dependent on the operational scenario and the site-specific conditions

  17. Utilization of artificial recharged effluent as makeup water for industrial cooling system: corrosion and scaling.

    Science.gov (United States)

    Wei, Liangliang; Qin, Kena; Zhao, Qingliang; Noguera, Daniel R; Xin, Ming; Liu, Chengcai; Keene, Natalie; Wang, Kun; Cui, Fuyi

    2016-01-01

    The secondary effluent from wastewater treatment plants was reused for industrial cooling water after pre-treatment with a laboratory-scale soil aquifer treatment (SAT) system. Up to a 95.3% removal efficiency for suspended solids (SS), 51.4% for chemical oxygen demand (COD), 32.1% for Cl(-) and 30.0% SO4(2-) were observed for the recharged secondary effluent after the SAT operation, which is essential for controlling scaling and corrosion during the cooling process. As compared to the secondary effluent, the reuse of the 1.5 m depth SAT effluent decreased the corrosion by 75.0%, in addition to a 55.1% decline of the scales/biofouling formation (with a compacted structure). The experimental results can satisfy the Chinese criterion of Design Criterion of the Industrial Circulating Cooling Water Treatment (GB 50050-95), and was more efficient than tertiary effluent which coagulated with ferric chloride. In addition, chemical structure of the scales/biofouling obtained from the cooling system was analyzed.

  18. An Industrial Perspective on Environmentally Assisted Cracking of Some Commercially Used Carbon Steels and Corrosion-Resistant Alloys

    Science.gov (United States)

    Ashida, Yugo; Daigo, Yuzo; Sugahara, Katsuo

    2017-08-01

    Commercial metals and alloys like carbon steels, stainless steels, and nickel-based super alloys frequently encounter the problem of environmentally assisted cracking (EAC) and resulting failure in engineering components. This article aims to provide a perspective on three critical industrial applications having EAC issues: (1) corrosion and cracking of carbon steels in automotive applications, (2) EAC of iron- and nickel-based alloys in salt production and processing, and (3) EAC of iron- and nickel-based alloys in supercritical water. The review focuses on current industrial-level understanding with respect to corrosion fatigue, hydrogen-assisted cracking, or stress corrosion cracking, as well as the dominant factors affecting crack initiation and propagation. Furthermore, some ongoing industrial studies and directions of future research are also discussed.

  19. Electrochemical corrosion of grinding media and effect of anions present in industrial waters; Corrosion electroquimica de medios de molienda y efecto de aniones presentes en aguas industriales

    Energy Technology Data Exchange (ETDEWEB)

    Magne, L.; Navarro, P.; Vargas, C.; Carrasco, S.

    2001-07-01

    The steel used in the minerals processing as grinding media (balls or bars), is an important input in terms of cost of the process. Considering the importance of the steel consumption in these processes, this work is guided to evaluate to laboratory scale the effect of the anions present in the industrial waters on the electrochemical corrosion of grinding media. Tests in electrochemical cell, were accomplished measuring potential and corrosion current to four electrodes that were manufactured using sufficiently pure sample of chalcopyrite, bornite, enargite and steel ball. The ions used in the tests were chlorides, sulfates, nitrates and carbonates in concentrations from 1 to 180 ppm in individual form or in mixtures, according to the levels measurement of these in industrial waters. (Author) 10 refs.

  20. Corrosion/95 conference papers

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    The papers in this conference represent the latest technological advances in corrosion control and prevention. The following subject areas are covered: cathodic protection in natural waters; materials for fossil fuel combustion and conversion systems; modern problems in atmospheric corrosion; innovative ideas for controlling the decaying infrastructure; deposits and their effects on corrosion in industry; volatile high temperature and non aqueous corrosion inhibitors; corrosion of light-weight and precoated metals for automotive application; refining industry corrosion; corrosion in pulp and paper industry; arctic/cold weather corrosion; materials selection for waste incinerators and associated equipment; corrosion measurement technology; environmental cracking of materials; advancing technology in the coating industry; corrosion in gas treating; green inhibition; recent advances in corrosion control of rail equipment; velocity effects and erosion corrosion in oil and gas production; marine corrosion; corrosion of materials in nuclear systems; underground corrosion control; corrosion in potable and industrial water systems in buildings and its impact on environmental compliance; deposit related boiler tube failures; boiler systems monitoring and control; recent developments and experiences in reactive metals; microbiologically influenced corrosion; corrosion and corrosion control for steel reinforced concrete; international symposium on the use of 12 and 13 Cr stainless steels in oil and gas production environments; subsea corrosion /erosion monitoring in production facilities; fiberglass reinforced pipe and tubulars in oilfield service; corrosion control technology in power transmission and distribution; mechanisms and methods of scale and deposit control; closing the loop -- results oriented cooling system monitoring and control; and minimization of aqueous discharge

  1. Factors affecting stress assisted corrosion cracking of carbon steel under industrial boiler conditions

    Science.gov (United States)

    Yang, Dong

    Failure of carbon steel boiler tubes from waterside has been reported in the utility boilers and industrial boilers for a long time. In industrial boilers, most waterside tube cracks are found near heavy attachment welds on the outer surface and are typically blunt, with multiple bulbous features indicating a discontinuous growth. These types of tube failures are typically referred to as stress assisted corrosion (SAC). For recovery boilers in the pulp and paper industry, these failures are particularly important as any water leak inside the furnace can potentially lead to smelt-water explosion. Metal properties, environmental variables, and stress conditions are the major factors influencing SAC crack initation and propagation in carbon steel boiler tubes. Slow strain rate tests (SSRT) were conducted under boiler water conditions to study the effect of temperature, oxygen level, and stress conditions on crack initation and propagation on SA-210 carbon steel samples machined out of boiler tubes. Heat treatments were also performed to develop various grain size and carbon content on carbon steel samples, and SSRTs were conducted on these samples to examine the effect of microstructure features on SAC cracking. Mechanisms of SAC crack initation and propagation were proposed and validated based on interrupted slow strain tests (ISSRT). Water chemistry guidelines are provided to prevent SAC and fracture mechanics model is developed to predict SAC failure on industrial boiler tubes.

  2. Preventive maintenance plan of the air-conditioning duct using the ACM-sensor

    International Nuclear Information System (INIS)

    Fukuba, Kazushi; Ito, Takanobu; Kojima, Akiko; Tanji, Kazuhiro; Sato, Yuki

    2013-01-01

    Air-conditioning duct is difficult to predict the date to occur of corrosion such as affect the function. Therefore, the current conservation method is mostly corrective maintenance. Therefore, we used the test pieces of six types and ACM-sensor in order to solve the corrosion speed from corrosion environment and relationship of corrosion quantity of test pieces. In addition, was used the duct molded articles various in order to check the corrosion degree of when processed the duct. As a result, we were selected crust body constituting a duct and optimal combination of the flange by solve the corrosion speed of the test pieces various. Thus, it performs preventive disposal before to occur of corrosion such as affect the function by predicting the duct life from corrosion speed, and lead to stability and safe operating by appropriate maintenance of equipment. (author)

  3. Stress corrosion cracking of low pressure turbine discs - an industry survey

    International Nuclear Information System (INIS)

    Lyle, F.F. Jr.; Lamping, G.A.; Leverant, G.R.

    1981-01-01

    Comprehensive industry survey identifies the key factors responsible for a large number of stress corrosion cracking incidents in low-pressure steam turbine discs of U.S. power plants. The survey included interviews with domestic and foreign utilities, as well as a review of available public documents. Plant operating practices, water treatment methods, turbine design and stress levels, and alloy chemistry and mechanical properties were among the principal variables considered in the study. Analyses of the data identified six potential key variables. Summaries of foreign and U.S. disc-cracking experience, relationship between variables and cracking experience, and the potential key cracking variables identified are presented in this paper. 11 refs

  4. Should you get your heating ducts cleaned?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Canada Mortgage and Housing Corporation conducted research into duct cleaning during which time several houses were tested for hot air furnace duct performance before and after cleaning. Duct cleaning is a major industry which claims that cleaning of ducts will provide you with better indoor air quality, reduce household molds and allergens, get rid of house dust, result in more airflow and better delivery of warm air and reduce energy costs. This report does not substantiate those claims. Researchers found little or no discernible differences in the concentrations of house airborne particles or in duct airflows due to duct cleaning. This is because ducts are metal passages that cannot create dust. Most household dusts come from outdoors that has been tracked in or blows through windows and other openings. While duct cleaning may be justifiable personally, it does not change the quality of the air you breathe, nor will it significantly affect airflow or heating costs. Some filters effectively clean the air in the ducts but they do not create a dust-free environment because of the above-mentioned dust sources. The only time that duct cleaning may make sense is if you have water in your ducts that can result in mold growth, if you are moving into a newly constructed house to remove drywall dust, if your are having trouble with furnace airflow, or if you see an accumulation of debris in the return air ducts. It was emphasized that broadcast spraying of biocides within the duct system should not be performed.

  5. Bile Duct Exploration

    Science.gov (United States)

    ... Home / Health Library / Diagnostics & Testing / Bile Duct Exploration Bile Duct Exploration Common bile duct exploration is a ... Test Details Results and Follow-Up What is bile, and what is bile duct exploration? Bile is ...

  6. Smart Multifunctional Coatings for Corrosion Detection and Control in the Aerospace Industry

    Science.gov (United States)

    Calle, Luz Marina

    2015-01-01

    Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. It is essential to detect corrosion when it occurs, and preferably at its early stage, so that action can be taken to avoid structural damage or loss of function. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it.

  7. Corrosion/94 conference papers

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    The approximately 500 papers from this conference are divided into the following sections: Rail transit systems--stray current corrosion problems and control; Total quality in the coatings industry; Deterioration mechanisms of alloys at high temperatures--prevention and remediation; Research needs and new developments in oxygen scavengers; Computers in corrosion control--knowledge based system; Corrosion and corrosivity sensors; Corrosion and corrosion control of steel reinforced concrete structures; Microbiologically influenced corrosion; Practical applications in mitigating CO 2 corrosion; Mineral scale deposit control in oilfield-related operations; Corrosion of materials in nuclear systems; Testing nonmetallics for life prediction; Refinery industry corrosion; Underground corrosion control; Mechanisms and applications of deposit and scale control additives; Corrosion in power transmission and distribution systems; Corrosion inhibitor testing and field application in oil and gas systems; Decontamination technology; Ozone in cooling water applications, testing, and mechanisms; Corrosion of water and sewage treatment, collection, and distribution systems; Environmental cracking of materials; Metallurgy of oil and gas field equipment; Corrosion measurement technology; Duplex stainless steels in the chemical process industries; Corrosion in the pulp and paper industry; Advances in cooling water treatment; Marine corrosion; Performance of materials in environments applicable to fossil energy systems; Environmental degradation of and methods of protection for military and aerospace materials; Rail equipment corrosion; Cathodic protection in natural waters; Characterization of air pollution control system environments; and Deposit-related problems in industrial boilers. Papers have been processed separately for inclusion on the data base

  8. Ultimate strength performance of tankers associated with industry corrosion addition practices

    Directory of Open Access Journals (Sweden)

    Kim Do Kyun

    2014-09-01

    Full Text Available In the ship and offshore structure design, age-related problems such as corrosion damage, local denting, and fatigue damage are important factors to be considered in building a reliable structure as they have a significant influence on the residual structural capacity. In shipping, corrosion addition methods are widely adopted in structural design to prevent structural capacity degradation. The present study focuses on the historical trend of corrosion addition rules for ship structural design and investigates their effects on the ultimate strength performance such as hull girder and stiffened panel of double hull oil tankers. Three types of rules based on corrosion addition models, namely historic corrosion rules (pre-CSR, Common Structural Rules (CSR, and harmonised Common Structural Rules (CSRH are considered and compared with two other corrosion models namely UGS model, suggested by the Union of Greek Shipowners (UGS, and Time-Dependent Corrosion Wastage Model (TDCWM. To identify the general trend in the effects of corrosion damage on the ultimate longitudinal strength performance, the corrosion addition rules are applied to four representative sizes of double hull oil tankers namely Panamax, Aframax, Suezmax, and VLCC. The results are helpful in understanding the trend of corrosion additions for tanker structures

  9. Ultimate strength performance of tankers associated with industry corrosion addition practices

    Directory of Open Access Journals (Sweden)

    Do Kyun Kim

    2014-09-01

    Full Text Available In the ship and offshore structure design, age-related problems such as corrosion damage, local denting, and fatigue damage are important factors to be considered in building a reliable structure as they have a significant influence on the residual structural capacity. In shipping, corrosion addition methods are widely adopted in structural design to prevent structural capacity degradation. The present study focuses on the historical trend of corrosion addition rules for ship structural design and investigates their effects on the ultimate strength performance such as hull girder and stiffened panel of double hull oil tankers. Three types of rules based on corrosion addition models, namely historic corrosion rules (pre-CSR, Common Structural Rules (CSR, and harmonised Common Structural Rules (CSRH are considered and compared with two other corrosion models namely UGS model, suggested by the Union of Greek Shipowners (UGS, and Time-Dependent Corrosion Wastage Model (TDCWM. To identify the general trend in the effects of corrosion damage on the ultimate longitudinal strength performance, the corrosion addition rules are applied to four representative sizes of double hull oil tankers namely Panamax, Aframax, Suezmax, and VLCC. The results are helpful in understanding the trend of corrosion additions for tanker structures.

  10. Corrosion Challenges for the Oil and Gas Industry in the State of Qatar

    Science.gov (United States)

    Johnsen, Roy

    In Qatar oil and gas has been produced from onshore fields in more than 70 years, while the first offshore field delivered its first crude oil in 1965. Due to the atmospheric conditions in Qatar with periodically high humidity, high chloride content, dust/sand combined with the temperature variations, external corrosion is a big treat to the installations and connecting infrastructure. Internal corrosion in tubing, piping and process systems is also a challenge due to high H2S content in the hydrocarbon mixture and exposure to corrosive aquifer water. To avoid corrosion different type of mitigations like application of coating, chemical treatment and material selection are important elements. This presentation will review the experiences with corrosion challenges for oil & gas installations in Qatar including some examples of corrosion failures that have been seen.

  11. Corrosion of stainless and carbon steels in molten mixtures of industrial nitrates

    Energy Technology Data Exchange (ETDEWEB)

    Goods, S.H.; Bradshaw, R.W. [Sandia National Labs., Livermore, CA (United States); Prairie, M.R.; Chavez, J.M. [Sandia National Labs., Albuquerque, NM (United States)

    1994-03-01

    Corrosion behavior of two stainless steels and carbon steel in mixtures of NaNO{sub 3} and KNO{sub 3} was evaluated to determine if impurities found in commodity grades of alkali nitrates aggravate corrosivity as applicable to an advanced solar thermal energy system. Corrosion tests were conducted for 7000 hours with Types 304 and 316 stainless steels at 570C and A36 carbon steel at 316C in seven mixtures of NaNO{sub 3} and KNO{sub 3} containing variations in impurity concentrations. Corrosion tests were also conducted in a ternary mixture of NaNO{sub 3}, KNO{sub 3}, and Ca(NO{sub 3}){sub 2}. Corrosion rates were determined by descaled weight losses while oxidation products were examined by scanning electron microscopy, electron microprobe analysis, and X-ray diffraction. The nitrate mixtures were periodically analyzed for changes in impurity concentrations and for soluble corrosion products.

  12. Mortar fights acid corrosion

    Energy Technology Data Exchange (ETDEWEB)

    1982-05-14

    The burning of coal or oil to produce heat required to operate a power boiler also generates a severe corrosion problem within the interior of the duct and stacks used to emit the flue gas into the atmosphere. How can concrete and steel be protected from the effects of acid attack, when the acids are carried in a gas form, or come into direct contact with the steel or concrete from spillage or immersion conditions. Industry in North America has found that the solution to this problem is to build an outside concrete column, in this case of Portland cement, and inside that column, build a totally independent brick liner bonded with Sauereisen mortar.

  13. Management and control of microbiologically influenced corrosion (MIC) in the oil and gas industry-Overview and a North Sea case study.

    Science.gov (United States)

    Skovhus, Torben Lund; Eckert, Richard B; Rodrigues, Edgar

    2017-08-20

    Microbiologically influenced corrosion (MIC) is the terminology applied where the actions of microorganisms influence the corrosion process. In literature, terms such as microbial corrosion, biocorrosion, microbially influenced/induced corrosion, and biodegradation are often applied. MIC research in the oil and gas industry has seen a revolution over the past decade, with the introduction of molecular microbiological methods: (MMM) as well as new industry standards and procedures of sampling biofilm and corrosion products from the process system. This review aims to capture the most important trends the oil and gas industry has seen regarding MIC research over the past decade. The paper starts out with an overview of where in the process stream MIC occurs - from the oil reservoir to the consumer. Both biotic and abiotic corrosion mechanisms are explained in the context of managing MIC using a structured corrosion management (CM) approach. The corrosion management approach employs the elements of a management system to ensure that essential corrosion control activities are carried out in an effective, sustainable, well-planned and properly executed manner. The 3-phase corrosion management approach covering of both biotic and abiotic internal corrosion mechanisms consists of 1) corrosion assessment, 2) corrosion mitigation and 3) corrosion monitoring. Each of the three phases are described in detail with links to recent field cases, methods, industry standards and sampling protocols. In order to manage the corrosion threat, operators commonly use models to support decision making. The models use qualitative, semi-quantitative or quantitative measures to help assess the rate of degradation caused by MIC. The paper reviews four existing models for MIC Threat Assessment and describe a new model that links the threat of MIC in the oil processing system located on an offshore platform with a Risk Based Inspection (RBI) approach. A recent field case highlights and explains

  14. Environmental stress-corrosion cracking of fiberglass: Lessons learned from failures in the chemical industry

    International Nuclear Information System (INIS)

    Myers, T.J.; Kytoemaa, H.K.; Smith, T.R.

    2007-01-01

    Fiberglass reinforced plastic (FRP) composite materials are often used to construct tanks, piping, scrubbers, beams, grating, and other components for use in corrosive environments. While FRP typically offers superior and cost effective corrosion resistance relative to other construction materials, the glass fibers traditionally used to provide the structural strength of the FRP can be susceptible to attack by the corrosive environment. The structural integrity of traditional FRP components in corrosive environments is usually dependent on the integrity of a corrosion-resistant barrier, such as a resin-rich layer containing corrosion resistant glass fibers. Without adequate protection, FRP components can fail under loads well below their design by an environmental stress-corrosion cracking (ESCC) mechanism when simultaneously exposed to mechanical stress and a corrosive chemical environment. Failure of these components can result in significant releases of hazardous substances into plants and the environment. In this paper, we present two case studies where fiberglass components failed due to ESCC at small chemical manufacturing facilities. As is often typical, the small chemical manufacturing facilities relied largely on FRP component suppliers to determine materials appropriate for the specific process environment and to repair damaged in-service components. We discuss the lessons learned from these incidents and precautions companies should take when interfacing with suppliers and other parties during the specification, design, construction, and repair of FRP components in order to prevent similar failures and chemical releases from occurring in the future

  15. Investigation of corrosion resistance of alloys with high mechanical characteristics in some environments of food industry

    International Nuclear Information System (INIS)

    Tremoureux, Yves

    1978-01-01

    This research thesis aimed at improving knowledge in the field of stress-free corrosion of alloys with high mechanical characteristics in aqueous environments, at highlighting some necessary aspects of their behaviour during cleaning or disinfection, and at selecting alloys which possess a good stress-free corrosion resistance in view of a later investigation of their stress corrosion resistance. After a presentation of the metallurgical characteristics of high mechanical strength alloys and the report of a bibliographical study on corrosion resistance of these alloys, the author presents and discusses the results obtained in the study of a possible migration of metallic ions in a milk product which is submitted to a centrifugation, and of the corrosion resistance of selected alloys with respect to the different media they will be in contact with during ultra-centrifugation. The following alloys have been used in this research: Marval 18, Marphynox, Marval X12, 17-4PH steel, Inconel 718 [fr

  16. Control of corrosive bacterial community by bronopol in industrial water system.

    Science.gov (United States)

    Narenkumar, Jayaraman; Ramesh, Nachimuthu; Rajasekar, Aruliah

    2018-01-01

    Ten aerobic corrosive bacterial strains were isolated from a cooling tower water system (CWS) which were identified based on the biochemical characterization and 16S rRNA gene sequencing. Out of them, dominant corrosion-causing bacteria, namely, Bacillus thuringiensis EN2, Terribacillus aidingensis EN3, and Bacillus oleronius EN9, were selected for biocorrosion studies on mild steel 1010 (MS) in a CWS. The biocorrosion behaviour of EN2, EN3, and EN9 strains was studied using immersion test (weight loss method), electrochemical analysis, and surface analysis. To address the corrosion problems, an anti-corrosive study using a biocide, bronopol was also demonstrated. Scanning electron microscopy and Fourier-transform infrared spectroscopy analyses of the MS coupons with biofilm developed after exposure to CWS confirmed the accumulation of extracellular polymeric substances and revealed that biofilms was formed as microcolonies, which subsequently cause pitting corrosion. In contrast, the biocide system, no pitting type of corrosion, was observed and weight loss was reduced about 32 ± 2 mg over biotic system (286 ± 2 mg). FTIR results confirmed the adsorption of bronopol on the MS metal surface as protective layer (co-ordination of NH 2 -Fe 3+ ) to prevent the biofilm formation and inhibit the corrosive chemical compounds and thus led to reduction of corrosion rate (10 ± 1 mm/year). Overall, the results from WL, EIS, SEM, XRD, and FTIR concluded that bronopol was identified as effective biocide and corrosion inhibitor which controls the both chemical and biocorrosion of MS in CWS.

  17. Bile Duct Cancer (Cholangiocarcinoma)

    Science.gov (United States)

    ... Home > Types of Cancer > Bile Duct Cancer (Cholangiocarcinoma) Bile Duct Cancer (Cholangiocarcinoma) This is Cancer.Net’s Guide to Bile Duct Cancer (Cholangiocarcinoma). Use the menu below to ...

  18. Lean duplex stainless steels-The role of molybdenum in pitting corrosion of concrete reinforcement studied with industrial and laboratory castings

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, T.J. [LEPMI, UMR5279CNRS, Grenoble INP, Universite de Savoie, Universite Joseph Fourier, BP 75, 38402 St Martin d' Heres (France); CRU Ugitech, Av Paul Girod 73400 Ugine (France); Chauveau, E.; Mantel, M. [CRU Ugitech, Av Paul Girod 73400 Ugine (France); Kinsman, N. [International Molybdenum Association, IMOA W4 4JE London (United Kingdom); Roche, V. [LEPMI, UMR5279CNRS, Grenoble INP, Universite de Savoie, Universite Joseph Fourier, BP 75, 38402 St Martin d' Heres (France); Nogueira, R.P., E-mail: ricardo.nogueira@grenoble-inp.fr [LEPMI, UMR5279CNRS, Grenoble INP, Universite de Savoie, Universite Joseph Fourier, BP 75, 38402 St Martin d' Heres (France)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Mo influence on corrosion of DSS was studied with industrial and laboratory heats. Black-Right-Pointing-Pointer Beneficial effect of Mo was associated with ferrite corrosion resistance. Black-Right-Pointing-Pointer Mo-species in the alkaline solution did not improve pit resistance. Black-Right-Pointing-Pointer Mo role in DSS under alkaline conditions was ascribed to its presence in oxide film. - Abstract: The influence of Mo addition on pitting corrosion resistance of lean duplex stainless steels is not clearly understood in alkaline chloride conditions even if this element is widely recognized to increase corrosion resistance in acidic and neutral environments. This work aims to study the effect of Mo on pitting corrosion of lean duplex stainless steels in synthetic concrete pore solutions simulating degraded concrete. Results are discussed with respect to the influence of Mo on pitting potential for two industrial alloys in chloride rich and carbonated solution simulating concrete pore environments. To establish the real effect of Mo addition on lean duplex corrosion and passivation properties, two specific laboratory lean duplex alloys, for which the only difference is strictly the Mo content, are also studied. Mo presented a strong positive influence on the pitting corrosion resistance of industrial and laboratory lean duplex stainless steels in all studied chloride-rich solutions, but its effect is as less pronounced as the pH increases. In presence of Mo, pitting initiates and propagates preferentially in the austenitic phase at high temperature.

  19. Applications in the Nuclear Industry for Corrosion-Resistant Amorphous-Metal Thermal-Spray Coatings

    International Nuclear Information System (INIS)

    Farmer, J; Choi, J

    2007-01-01

    Amorphous metal and ceramic thermal spray coatings have been developed that can be used to enhance the corrosion resistance of containers for the transportation, aging and disposal of spent nuclear fuel and high-level radioactive wastes. Fe-based amorphous metal formulations with chromium, molybdenum and tungsten have shown the corrosion resistance believed to be necessary for such applications. Rare earth additions enable very low critical cooling rates to be achieved. The boron content of these materials, and their stability at high neutron doses, enable them to serve as high efficiency neutron absorbers for criticality control. Ceramic coatings may provide even greater corrosion resistance for container applications, though the boron-containing amorphous metals are still favored for criticality control applications. These amorphous metal and ceramic materials have been produced as gas atomized powders and applied as near full density, non-porous coatings with the high-velocity oxy-fuel process. This paper summarizes the performance of these coatings as corrosion-resistant barriers, and as neutron absorbers. Relevant corrosion models are also discussed, as well as a cost model to quantify the economic benefits possible with these new materials

  20. ANÁLISIS DE CORROSIÓN EN DUCTOS DE CONDUCCIÓN DE GASES EN UNA PLANTA DE CLINKER CORROSION ANALYSIS IN GAS CONDUCTION DUCTS IN A CLINKER PLANT

    Directory of Open Access Journals (Sweden)

    Alex Humberto Restrepo Carvajal

    2009-04-01

    Full Text Available En este trabajo se presentan los resultados de un estudio detallado de las causas del deterioro observado en ductos metálicos de una planta productora de cemento. Para el análisis, se inició con una minuciosa inspección visual, tomando muestras de sustratos, productos de corrosión y gases de proceso. Al mismo tiempo se realizaron medidas de potencial de estructura, espesores de pared y temperaturas de superficies. Para la evaluación de la agresividad del ambiente se instalaron captadores de contaminantes (cloruros, sulfatos y óxidos de nitrógeno. Las muestras recolectadas se analizaron por medio de microscopia óptica y electrónica de barrido, espectroscopia EDS, difracción de rayos X, espectroscopia infrarroja y cromatografía iónica. Los gases se analizaron insitu siguiendo el procedimiento EPA-2. Los resultados para las superficies externas indican una atmósfera con agresividad C3 según la norma ISO 9223, observando influencia de la alta temperatura, largos periodos de humectación, material particulado y errores en la selección del sistema de protección. Las capas de productos al exterior son uniformes, compactas y son compuestas principalmente por hematita. Al interior de los ductos se presentan procesos de sulfurización y oxidación; el ataque por azufre es localizado y genera perforación de las paredes metálicas. Los productos encontrados son mayormente sulfatos de hierro y Fe2O3. Los procedimientos empleados y los resultados obtenidos son útiles para la toma de decisiones en mantenimiento y protección contra la corrosión de este tipo de instalaciones.The results of a detailed study of the causes of deterioration, observed in metallic ducts in a cement production plant are presented. The analysis started with a careful visual inspection, collecting samples of substrates, corrosion products and process gases. At the same time, measurements of potential, wall thickness and surface temperatures were carried out. For

  1. Bio-testing integral toxicity of corrosion inhibitors, biocides and oil hydrocarbons in oil-and gas-processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Chugunov, V.A.; Kholodenko, V.P.; Irkhina, I.A.; Fomchenkov, V.M.; Novikov, I.A. [State Research Center for Applied Microbiology, Obolensk, Moscow (Russian Federation)

    2004-07-01

    In recent years bioassays have been widely used for assessing levels of contamination of the environment. This is due to the fact that test-organisms provide a general response to toxicants present in samples. Based on microorganisms as test objects, it is possible to develop cheap, sensitive and rapid assays to identify environmental xenobiotics and toxicants. The objective of the research was to develop different microbiological assays for assessing integral toxicity of water environments polluted with corrosion inhibitors, biocides and hydrocarbons in oil- and gas-processing industry. Bio-luminescent, electro-orientational, osmo-optic and microorganism reducing activity assays were used for express evaluation of integral toxicity. They are found to determine promptly integral toxicity of water environments containing various pollutants (oil, oil products, corrosion inhibitors, biocides). Results conclude that the assays may be used for analyzing integral toxicity of water polluted with hydrocarbons, as well as for monitoring of water changes as a result of biodegradation of pollutants by microorganisms and their associations. Using a kit of different assays, it is also possible to evaluate ecological safety of biocides, corrosion inhibitors, and their compositions. Bioassays used as a kit are more effective than each assay individually, allowing one to get complete characterization of a reaction of bacterial test organisms to different environments. (authors)

  2. Corrosion and deposit evaluation in industrial plants by non destructive testing method

    International Nuclear Information System (INIS)

    Azali Muhammad; Abd Razak Hamzah; Abd Aziz Mohamed; Mohd Pauzi Ismail; S Saad; S Sayuti; S Ahmad

    2000-01-01

    In petrochemical plants, the detection of corrosion and evaluation of deposit in insulated pipes using a radiography method are very challenging tasks. This main degradation problem experienced by pipelines is due to water condensation. It will cause deposit and scale inside the pipe, as well as between the insulation and pipe for the cold temperature pipes. On the other hand, for the hot temperature pipes the main problem is mainly due to corrosion/erosion attack inside the pipe. In the case of corrosion study one of the most important parameters in a piping or pipeline to be monitored and measured is that the wall thickness. In general, most pipeline corrosion monitoring and evaluation for both insulated and non-insulated pipes is done by using an ultrasonic method. The most common technique for corrosion is that based on the A-Scan, using either a normal flow detector or some form of dedicated equipment. However, with recent development of ultrasonic technology, more advance method, namely B-Scan and C-scan techniques are also available. The most notable disadvantage of using this current method is that the insulation covered the pipe has to be removed before the inspection can be carried out and this is considered as not so cost effective. Due to this reason other alternative NDT method, namely radiographic testing method has been studied. The testing technique used in this studied are tangential technique and double wall radiographic technique which involve studying the changing in density of radiographic film. The result found using tangential technique is consistent with real thickness of the pipe. However for the later technique the result is only achieved with a reasonable accuracy when the changing in wall thickness is very small. The result of the studies is discussed in this paper

  3. Preparation of ceramic-corrosion-cell fillers and application for cyclohexanone industry wastewater treatment in electrobath reactor

    International Nuclear Information System (INIS)

    Wu, Suqing; Qi, Yuanfeng; Gao, Yue; Xu, Yunyun; Gao, Fan; Yu, Huan; Lu, Yue; Yue, Qinyan; Li, Jinze

    2011-01-01

    Highlights: ► Dried sewage sludge and scrap iron used as raw materials for sintering ceramics. ► The new media ceramics used as fillers in electrobath of micro-electrolysis. ► Modified micro-electrolysis used in cyclohexanone industry wastewater treatment. ► This modified micro-electrolysis could avoid failure of the electrobath reactor. - Abstract: As new media, ceramic-corrosion-cell fillers (Cathode Ceramic-corrosion-cell Fillers – CCF, and Anode Ceramic-corrosion-cell Fillers – ACF) employed in electrobath were investigated for cyclohexanone industry wastewater treatment. 60.0 wt% of dried sewage sludge and 40.0 wt% of clay, 40.0 wt% of scrap iron and 60.0 wt% of clay were utilized as raw materials for the preparation of raw CCF and ACF, respectively. The raw CCF and ACF were respectively sintered at 400 °C for 20 min in anoxic conditions. The physical properties (bulk density, grain density and water absorption), structural and morphological characters and toxic metal leaching contents were tested. The influences of pH, hydraulic retention time (HRT) and the media height on removal of COD Cr and cyclohexanone were studied. The results showed that the bulk density and grain density of CCF and ACF were 869.0 kg m −3 and 936.3 kg m −3 , 1245.0 kg m −3 and 1420.0 kg m −3 , respectively. The contents of toxic metal (Cu, Zn, Cd, Pb, Cr, Ba, Ni and As) were all below the detection limit. When pH of 3–4, HRT of 6 h and the media height of 60 cm were applied, about 90% of COD cr and cyclohexanone were removed.

  4. Preparation of ceramic-corrosion-cell fillers and application for cyclohexanone industry wastewater treatment in electrobath reactor

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Suqing; Qi, Yuanfeng; Gao, Yue; Xu, Yunyun; Gao, Fan; Yu, Huan; Lu, Yue [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, 250100 Jinan (China); Yue, Qinyan, E-mail: qyyue58@yahoo.com.cn [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, 250100 Jinan (China); Li, Jinze [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, 250100 Jinan (China)

    2011-11-30

    Highlights: Black-Right-Pointing-Pointer Dried sewage sludge and scrap iron used as raw materials for sintering ceramics. Black-Right-Pointing-Pointer The new media ceramics used as fillers in electrobath of micro-electrolysis. Black-Right-Pointing-Pointer Modified micro-electrolysis used in cyclohexanone industry wastewater treatment. Black-Right-Pointing-Pointer This modified micro-electrolysis could avoid failure of the electrobath reactor. - Abstract: As new media, ceramic-corrosion-cell fillers (Cathode Ceramic-corrosion-cell Fillers - CCF, and Anode Ceramic-corrosion-cell Fillers - ACF) employed in electrobath were investigated for cyclohexanone industry wastewater treatment. 60.0 wt% of dried sewage sludge and 40.0 wt% of clay, 40.0 wt% of scrap iron and 60.0 wt% of clay were utilized as raw materials for the preparation of raw CCF and ACF, respectively. The raw CCF and ACF were respectively sintered at 400 Degree-Sign C for 20 min in anoxic conditions. The physical properties (bulk density, grain density and water absorption), structural and morphological characters and toxic metal leaching contents were tested. The influences of pH, hydraulic retention time (HRT) and the media height on removal of COD{sub Cr} and cyclohexanone were studied. The results showed that the bulk density and grain density of CCF and ACF were 869.0 kg m{sup -3} and 936.3 kg m{sup -3}, 1245.0 kg m{sup -3} and 1420.0 kg m{sup -3}, respectively. The contents of toxic metal (Cu, Zn, Cd, Pb, Cr, Ba, Ni and As) were all below the detection limit. When pH of 3-4, HRT of 6 h and the media height of 60 cm were applied, about 90% of COD{sub cr} and cyclohexanone were removed.

  5. Effect of Corrosion in the CS Operation Indoors of the Electronics Industry in the Northwest of Mexico

    Directory of Open Access Journals (Sweden)

    González-Kleyton J.

    2012-10-01

    Full Text Available The electronics industry is an important factor in Mexico's economy, representing 80% of companies in the northwest of this country, where we find Mexicali (as arid zone and Tijuana (as marine region, two cities in the state Baja California, adjacent to cities in California, USA, on the border of Mexico-United States. A study was conducted indoors in three plants of each city mentioned above, to determine if corrosion phenomena has an effect on the lifetime and productive performance of the CS. The results show that major air pollutants present indoors, that generate aggressive environments in Mexicali are the sulfides, while in Tijuana are the chlorides, which affect the functioning of the CS, and originate electrical failures in industrial equipments and machines.

  6. Corrosion/96 conference papers

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    Topics covered by this conference include: cathodic protection in natural waters; cleaning and repassivation of building HVAC systems; worldwide opportunities in flue gas desulfurization; advancements in materials technology for use in oil and gas service; fossil fuel combustion and conversion; technology of corrosion inhibitors; computers in corrosion control--modeling and information processing; recent experiences and advances of austenitic alloys; managing corrosion with plastics; corrosion measurement technology; corrosion inhibitors for concrete; refining industry; advances in corrosion control for rail and tank trailer equipment; CO 2 corrosion--mechanisms and control; microbiologically influenced corrosion; corrosion in nuclear systems; role of corrosion in boiler failures; effects of water reuse on monitoring and control technology in cooling water applications; methods and mechanisms of scale and deposit control; corrosion detection in petroleum production lines; underground corrosion control; environmental cracking--relating laboratory results and field behavior; corrosion control in reinforced concrete structures; corrosion and its control in aerospace and military hardware; injection and process addition facilities; progress reports on the results of reinspection of deaerators inspected or repaired per RP0590 criteria; near 100% volume solids coating technology and application methods; materials performance in high temperature environments containing halides; impact of toxicity studies on use of corrosion/scale inhibitors; mineral scale deposit control in oilfield related operations; corrosion in gas treating; marine corrosion; cold climate corrosion; corrosion in the pulp and paper industry; gaseous chlorine alternatives in cooling water systems; practical applications of ozone in recirculating cooling water systems; and water reuse in industry. Over 400 papers from this conference have been processed separately for inclusion on the data base

  7. Fighting corrosion in India

    Energy Technology Data Exchange (ETDEWEB)

    Rajagopalan, K S; Rangaswamy, N S

    1979-03-01

    A survey covers the cost of corrosion in India; methods of preventing corrosion in industrial plants; some case histories, including the prevention of corrosion in pipes through which fuels are pumped to storage and the stress-corrosion cracking of evaporators in fertilizer plants; estimates of the increase in demand in 1979-89 for anticorrosion products and processes developed by the Central Electrochemical Research Institute (CECRI) at Karaikudi, India; industries that may face corrosion problems requiring assistance from CECRI, including the light and heavy engineering structural, and transport industries and the chemical industry; and some areas identified for major efforts, including the establishment of a Corrosion Advisory Board with regional centers and the expansion of the Tropical Corrosion Testing Station at Mandapam Camp, Tamil Nadu.

  8. The use of nitrogen to improve the corrosion resistance of FeCrNiMo alloys for the chemical process industries

    Energy Technology Data Exchange (ETDEWEB)

    Kearns, J.R.; Deverell, H.E.

    1987-06-01

    The addition of 0.1 to 0.25 wt% nitrogen to austenitic alloys has been shown to enhance resistance to localized corrosion in oxidizing chloride and reducing acid solutions. Further tests of FeCrNiMo alloys assess the effects of nitrogen additions on: mechanical properties, chloride and caustic stress corrosion cracking resistance, passivation characteristics, and general corrosion rates in various acid, alkali, and salt solutions pertinent to the chemical process industries. The precipitation of chromium-rich secondary phases was retarded by solid solution additions of 0.1 to 0.25 wt% nitrogen. The corrosion resistance of FeCrNiMoN alloys in the welded condition was improved by using shield-gas mixtures of argon and 2.5 to 5.0 wt% nitrogen.

  9. Atmospheric corrosion resistance of epoxy duplex coated electrogalvanized steel exposed in marine, industrial and urban sites at pakistan

    International Nuclear Information System (INIS)

    Bano, H.; Kazmi, S.A.

    2017-01-01

    An epoxy based duplex coating system (Electrogalvanized Mild Steel/Etch Primer/Epoxy-Polyamide Primer/ Epoxy-Amine Topcoat System) embedded with iron oxide, zinc chromate and titanium dioxide pigments was studied to ascertain its corrosion resistant synergistic performance at various anthropogenic sites of Karachi coastal city while salt spray test was also executed for reference. Coating performance was ascertained by visual morphological inspection, gloss measurements, Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray (EDX) analysis and by Fourier Transform Infrared (FTIR) Spectroscopy. SEM and EDX results corroborated high degradation of epoxy coating at marine site experiment as substantial increment in oxygen/carbon ratio and high concentration of Ti at coating surface due to ex-corporation of pigments were noticed. Worst performance of epoxy coating at marine test site as compared to salt spray testing may be due to the salt-laden winds of Karachi coastal city and corrosive constituents incorporated in atmospheres from industrial and automobiles exhaust. General diminution trend in gloss value, depletion of morphological features witnessed through SEM micrographs, curtailment of aryl ether and aromatic nuclei signals in FTIR spectrum, and emergence of new peaks in the 1620-1800 cm-1 region correspond to formation of new oxidation products; concluded that an insignificant protection offered by the epoxy coating due to its outdoor aging which led to ex-capsulation of pigments under moist conditions. Appraisal of these results have furnished an average coating performance correlation of 547.5 hpy (hours of salt spray test equivalence per year exposure test) at marine test site and 528 hpy at industrial test site in terms of blistering while equivalence mean in terms of rusting were found 680 hpy and 567 hpy at marine and industrial test sites respectively. (author)

  10. Bile duct stricture

    Science.gov (United States)

    ... duct, the tube that moves bile from the liver to the small intestine. Bile is a substance that helps with digestion. ... causes of this condition include: Cancer of the bile duct, liver or pancreas Damage and scarring due to a ...

  11. Erosion-corrosion

    International Nuclear Information System (INIS)

    Aghili, B.

    1999-05-01

    A literature study on erosion-corrosion of pipings in the nuclear industry was performed. Occurred incidents are reviewed, and the mechanism driving the erosion-corrosion is described. Factors that influence the effect in negative or positive direction are treated, as well as programs for control and inspection. Finally, examples of failures from databases on erosion-corrosion are given in an attachment

  12. Protection of Mild Steel Against Sulphides Corrosion In Petroleum Oil Industry

    International Nuclear Information System (INIS)

    Soliman, A.M.H.

    2004-01-01

    The aggressive properties of the media encountered when drilling for oil derive from the fact that they contain an abundance of mineralized water, as well as hydrogen sulphide and carbon dioxide. Particularly vulnerable to corrosion and installation of old deposits, where highly mineralized water or sometimes even sea water, is pumped into the bed so as to increase the oil yield, and where acid treatment is also carried out, the injection of such water into the bed creates favourable conditions for the development of microbiological processes promoting the life activity of sulphate-reducing bacteria and contributing to the appearance of hydrogen sulphide in the system

  13. Control of Microbiologically Induced Corrosion in Petroleum Industry Using Various Preventive Strategies

    International Nuclear Information System (INIS)

    Zakaria, A.E.; Abdelaal, N.M.; Gebreil, H.M.

    2012-01-01

    Various inhibitive strategies were used to control Sulfate reducing bacteria (SRB). The traditional treatment of SRB by biocides was compared with other treatments such as exposure to microwaves, ultraviolet, gamma radiation separately and addition of either nitrate or nitrite. Six commercial biocides were tested for SRB control. Champion- A was found to be the most efficient biocides. Addition of nitrate to SRB growth medium did not inhibit the growth at 10 m M/l whereas addition of 6 m M/L nitrite completely inhibited the growth. On the other hand, physical treatments achieved satisfactory results. the lethal doses required for complete inhibition of the growth on using microwave, ultraviolet and gamma radiations were found to be at (50 second, 4 hours and 0.9 KGy) respectively. On studying the effect of the lethal and sublethal doses of different treatment on the growth and sulfide production rates of SRB, it was found that the lethal doses of all studied treatments except nitrate treatment achieved complete inhibition. Also the corrosion aspects and elemental analysis of metal coupons surfaces at such doses showed a clear variation in distribution and composition of the corrosion products adhered to their surfaces.

  14. Recent Research and Development in Solving Atmospheric Corrosion Problems of Steel Industries in Japan

    International Nuclear Information System (INIS)

    Yamashita, M.; Uchida, H.

    2002-01-01

    A rust layer, so called 'protective' rust layer, on a weathering low-alloy steel has strong protective ability for atmospheric corrosion of the steel. We have recently found through a large number of spectroscopic studies including Moessbauer spectroscopy that the protective rust layer forms after long-term phase transformation. The phase and structure of the rust definitely control the protective ability of the rust layer. From this recent knowledge, some new technologies have been developed. One is the surface-treatment technique that provides a possibility for obtaining the protective rust layer in a relatively short period even in the severe environments such as in marine and chloride (de-icing salts) containing environments. Others are based on selection of effective alloying elements for steel materials. These are particularly important for application in areas where protective rust layer formation may be hindered or prevented. In this paper, we mention recent progress in research and development on rusting protection by rust for atmospheric corrosion of steels in Japan.

  15. Catastrophes caused by corrosion

    OpenAIRE

    PETROVIC ZORAN C.

    2016-01-01

    For many years, huge attention has been paid to the problem of corrosion damage and destruction of metallic materials. Experience shows that failures due to corrosion problems are very important, and statistics at the world level shows that the damage resulting from the effects of various forms of corrosion is substantial and that, for example, in industrialized countries it reaches 4-5% of national incomes. Significant funds are determined annually for the prevention and control of corrosion...

  16. Corrosion of metallic materials. Dry corrosion, aqueous corrosion and corrosion by liquid metal, methods of protection

    International Nuclear Information System (INIS)

    Helie, Max

    2015-01-01

    This book is based on a course on materials given in an engineering school. The author first gives an overview of metallurgy issues: metallic materials (pure metals, metallic alloys), defects of crystal lattices (point defects, linear defects or dislocations), equilibrium diagrams, steels and cast, thermal processing of steels, stainless steels, aluminium and its alloys, copper and its alloys. The second part addresses the properties and characterization of surfaces and interfaces: singularity of a metal surface, surface energy of a metal, energy of grain boundaries, adsorption at a material surface, metal-electrolyte interface, surface oxide-electrolyte interface, techniques of surface analysis. The third chapter addresses the electrochemical aspects of corrosion: description of the corrosion phenomenon, free enthalpy of a compound and free enthalpy of a reaction, case of dry corrosion (thermodynamic aspect, Ellingham diagram, oxidation mechanisms, experimental study, macroscopic modelling), case of aqueous corrosion (electrochemical thermodynamics and kinetics, experimental determination of corrosion rate). The fourth part addresses the different forms of aqueous corrosion: generalized corrosion (atmospheric corrosion, mechanisms and tests), localized corrosion (galvanic, pitting, cracking, intergranular, erosion and cavitation), particular cases of stress cracking (stress corrosion, fatigue-corrosion, embrittlement by hydrogen), and bi-corrosion (of non alloyed steels, of stainless steels, and of aluminium and copper alloys). The sixth chapter addresses the struggle and the protection against aqueous corrosion: methods of prevention, scope of use of main alloys, geometry-based protection of pieces, use of corrosion inhibitors, use of organic or metallic coatings, electrochemical protection. The last chapter proposes an overview of corrosion types in industrial practices: in the automotive industry, in the oil industry, in the aircraft industry, and in the

  17. Management and control of microbiologically influenced corrosion (MIC) in the oil and gas industry - Overview and a North Sea case study

    DEFF Research Database (Denmark)

    Skovhus, Torben Lund; Eckert, Richard B; Rodrigues, Edgar

    2017-01-01

    the oil and gas industry has seen regarding MIC research over the past decade. The paper starts out with an overview of where in the process stream MIC occurs - from the oil reservoir to the consumer. Both biotic and abiotic corrosion mechanisms are explained in the context of managing MIC using...... to manage the corrosion threat, operators commonly use models to support decision making. The models use qualitative, semi-quantitative or quantitative measures to help assess the rate of degradation caused by MIC. The paper reviews four existing models for MIC Threat Assessment and describe a new model...

  18. Corrosion Mechanism of Low-Carbon Steel in Industrial Water and Adsorption Thermodynamics in the Presence of Some Plant Extracts

    Science.gov (United States)

    Badiea, A. M.; Mohana, K. N.

    2009-12-01

    The effects of radish leaves and black cumin as plant extracts on the corrosion behavior of low-carbon steel in industrial water in the temperature range of 30 to 80 °C and velocity range of 1.44 to 2.02 m s-1 using potentiodynamic polarization, electrochemical impedance spectroscopy, and mass loss measurements have been investigated. The inhibition efficiency increased with increasing concentration of the plant extracts up to a critical value but it slightly decreased with increasing temperature. Inhibition efficiency values obtained from mass loss and potentiodynamic data were in reasonable agreement. Potentiodynamic polarization clearly indicated that radish leaves and black cumin extracts acted as anodic inhibitors. The adsorption behavior was found to obey the Flory-Huggins isotherm model. The associated activation parameters and thermodynamic data of adsorption were evaluated and discussed. The results show that radish leaves and black cumin could serve as effective inhibitors for low-carbon steel in industrial water media, with black cumin providing better protection than radish leaves.

  19. [Assessment of biological corrosion of ferroconcrete of ground-based industrial structures].

    Science.gov (United States)

    Rozhanskaia, A M; Piliashenko-Novokhatnyĭ, A I; Purish, L M; Durcheva, V N; Kozlova, I A

    2001-01-01

    One of the objects of a nuclear plant built in 1983 and put in 15-years long dead storage with the purpose to estimate the degree of contamination by rust-hazardous microorganisms of ferroconcrete structures and to predict their biocorrosion state after putting in operation was a subject of microbiological investigation. The everywhere distribution of sulphur cycle bacteria (thionic and sulphate-reducing bacteria) on the surface and in the bulk of concrete structures, their confineness to corrosion products of concrete and bars of the investigated building have been shown. It has been demonstrated that sulphate-reducing bacteria were the most distributed group in all the sampling points. An indirect estimation of participation degree of the microbial communities in the processes of ferroconcrete biological damages has been carried out as based on the accumulation intensity of aggressive gaseous metabolites--carbon dioxide and hydrogen. Probability of deterioration of biocorrosion situation under the full-scale operation of the object has been substantiated.

  20. Corrosion control for low-cost reliability

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This conference was held September 19-24, 1993 in Houston, Texas to provide a forum for exchange of state-of-the-art information on corrosion. Topics of interest focus on the following: atmospheric corrosion; chemical process industry corrosion; high temperature corrosion; and corrosion of plant materials. Individual papers have been processed separately for inclusion in the appropriate data bases

  1. Section 2: Corrosion and failure analysis studies in support of the pulp and paper industry

    Energy Technology Data Exchange (ETDEWEB)

    Keiser, J.R.; Pawel, S.J.; Swindeman, R.W.; Longmire, H.F. [Oak Ridge National Lab., TN (United States)

    1997-04-01

    Technical support is being provided to various pulp and paper companies and related industries to help determine the cause of material degradation problems and to identify alternate materials to prevent such degradation. During the past year, examinations have included parts from several sootblowers, two failed economizer tubes, and inspection of a continuous digester. The results of the analyses and inspections were communicated to the plant operators, and, in some cases, recommendations were made. This article discusses examination of sootblower nozzles, which evidenced intergranular cracking. Analysis indicated the presence of chromium carbide precipitates along the grain boundaries, which can cause the sample to be sensitized to grain boundary attack.

  2. Blocked Tear Duct

    Science.gov (United States)

    ... of the nose (lacrimal sac). From there tears travel down a duct (the nasolacrimal duct) draining into your nose. Once in the nose, tears are reabsorbed. A blockage can occur at any point in the tear drainage system, from the puncta ...

  3. Corrosion and corrosion control

    International Nuclear Information System (INIS)

    Khanna, A.S.; Totlani, M.K.

    1995-01-01

    Corrosion has always been associated with structures, plants, installations and equipment exposed to aggressive environments. It effects economy, safety and product reliability. Monitoring of component corrosion has thus become an essential requirement for the plant health and safety. Protection methods such as appropriate coatings, cathodic protection and use of inhibitors have become essential design parameters. High temperature corrosion, especially hot corrosion, is still a difficult concept to accommodate in corrosion allowance; there is a lack of harmonized system of performance testing of materials at high temperatures. In order to discuss and deliberate on these aspects, National Association for Corrosion Engineers International organised a National Conference on Corrosion and its Control in Bombay during November 28-30, 1995. This volume contains papers presented at the symposium. Paper relevant to INIS is indexed separately. refs., figs., tabs

  4. Dictionary corrosion and corrosion control

    International Nuclear Information System (INIS)

    1985-01-01

    This dictionary has 13000 entries in both languages. Keywords and extensive accompanying information simplify the choice of word for the user. The following topics are covered: Theoretical principles of corrosion; Corrosion of the metals and alloys most frequently used in engineering. Types of corrosion - (chemical-, electro-chemical, biological corrosion); forms of corrosion (superficial, pitting, selective, intercrystalline and stress corrosion; vibrational corrosion cracking); erosion and cavitation. Methods of corrosion control (material selection, temporary corrosion protection media, paint and plastics coatings, electro-chemical coatings, corrosion prevention by treatment of the corrosive media); Corrosion testing methods. (orig./HP) [de

  5. A Comparison of Simulation Capabilities for Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Miller, William A [ORNL; Smith, Matt K [ORNL; Gu, Lixing [Florida Solar Energy Center (FSEC); New, Joshua Ryan [ORNL

    2014-11-01

    Typically, the cheapest way to install a central air conditioning system in residential buildings is to place the ductwork in the attic. Energy losses due to duct-attic interactions can be great, but current whole-house models are unable to capture the dynamic multi-mode physics of the interactions. The building industry is notoriously fragmented and unable to devote adequate research resources to solve this problem. Builders are going to continue to put ducts in the attic because floor space is too expensive to closet them within living space, and there are both construction and aesthetic issues with other approaches such as dropped ceilings. Thus, there is a substantial need to publicly document duct losses and the cost of energy used by ducts in attics so that practitioners, builders, homeowners and state and federal code officials can make informed decisions leading to changes in new construction and additional retrofit actions. Thus, the goal of this study is to conduct a comparison of AtticSim and EnergyPlus simulation algorithms to identify specific features for potential inclusion in EnergyPlus that would allow higher-fidelity modeling of HVAC operation and duct transport of conditioned air. It is anticipated that the resulting analysis from these simulation tools will inform energy decisions relating to the role of ducts in future building energy codes and standards.

  6. The effect of zinc bath temperature on the morphology, texture and corrosion behaviour of industrially produced hot-dip galvanized coatings

    Directory of Open Access Journals (Sweden)

    A. Bakhtiari

    2014-03-01

    Full Text Available The purpose of this work is to identify the influence of zinc bath temperature on the morphology, texture and corrosion behavior of hot-dip galvanized coatings. Hot-dip galvanized samples were prepared at temperature in the range of 450-480 °C in steps of 10 °C, which is the conventional galvanizing temperature range in the galvanizing industries. The morphology of coatings was examined with optical microscopy and scanning electron microscopy (SEM. The composition of the coating layers was determined using energy dispersive spectroscopy (EDS analysis. The texture of the coatings was evaluated using X-ray diffraction. Corrosion behavior was performed using salt spray cabinet test and Tafel extrapolation test. From the experimental results, it was found that increasing the zinc bath temperature affects the morphology of the galvanized coatings provoking the appearance of cracks in the coating structure. These cracks prevent formation of a compact structure. In addition, it was concluded that (00.2 basal plane texture component was weakened by increasing the zinc bath temperature and, conversely, appearance of (10.1 prism component, (20.1 high angle pyramidal component and low angle component prevailed. Besides, coatings with strong (00.2 texture component and weaker (20.1 components have better corrosion resistance than the coatings with weak (00.2 and strong (20.1 texture components. Furthermore, corrosion resistance of the galvanized coatings was decreased by increasing the zinc bath temperature.

  7. Compact Buried Ducts in a Hot-Humid Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, Dave [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2016-01-07

    "9A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely on encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences; 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs; 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.

  8. Modified nasolacrimal duct stenting

    International Nuclear Information System (INIS)

    Tian Min; Jin Mei; Chen Huanjun; Li Yi

    2008-01-01

    Objective: Traditional nasolacrimal duct stenting possesses some shortcoming including difficulty of pulling ball head guide wire from the nasal cavity with turbinate hypertrophy and nasal septal deviation. The new method of nose-oral tube track establishment can overcome the forementioned and increase the successful rate. Methods: 5 F catheter and arterial sheath were modified to be nasolacrimal duct stent delivery device respectively. Antegrade dacryocystography was taken firstly to display the obstructed site and followed by the modified protocol of inserting the guide wire through nasolacrimal duct and nasal cavity, and establishing the stent delivery track for retrograde stent placement. Results: 5 epiphora patients with failure implantation by traditional method were all succeeded through the modified stenting (100%). During 6-mouth follow-up, no serious complications and reocclusion occurred. Conclusion: The establishment of eye-nose-mouth-nose of external nasal guide wire track can improve the successful rate of nasolacrimal duct stenting. (authors)

  9. Bile duct obstruction

    Science.gov (United States)

    ... Tumors that have spread to the biliary system Liver and bile duct worms (flukes) The risk factors include: History of ... Increased bilirubin level Increased alkaline phosphatase level Increased liver enzymes The ... CT scan Endoscopic retrograde cholangiopancreatography ( ...

  10. Ducted fuel injection

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Charles J.

    2018-03-06

    Various technologies presented herein relate to enhancing mixing inside a combustion chamber to form one or more locally premixed mixtures comprising fuel and charge-gas with low peak fuel to charge-gas ratios to enable minimal, or no, generation of soot and other undesired emissions during ignition and subsequent combustion of the locally premixed mixtures. To enable sufficient mixing of the fuel and charge-gas, a jet of fuel can be directed to pass through a bore of a duct causing charge-gas to be drawn into the bore creating turbulence to mix the fuel and the drawn charge-gas. The duct can be located proximate to an opening in a tip of a fuel injector. The duct can comprise of one or more holes along its length to enable charge-gas to be drawn into the bore, and further, the duct can cool the fuel and/or charge-gas prior to combustion.

  11. Mode of corrosion monitoring by electrochemical measurements in alkaline water solutions at 310 degC using a new type of industrial probes with high radiation stability

    International Nuclear Information System (INIS)

    Beran, J.

    1977-01-01

    Application of the linear polarization method to Zr-alloys and low-alloy steel was successfully verified by autoclave tests in alkaline water solutions, pH=10.3 max. The new type of industrial probes for electrochemical measurements worked 5500 hours at temperatures within 250 and 310 degC. Contrary to usual practice, the corrosion rate was evaluated applying the criterion T/Rsub(p) instead of criterion 1/Rsub(p). A single calibration curve T/Rsub(p) versus corrosion rate, which is independent of test temperature, was introduced in this way. The probes, developed by SKODA-Works, Nuclear Power Construction Division for electrochemical measurements in nuclear reactor environment, do not contain organic compounds (for sealing, insulation etc.) in order to prevent radiation damage. (author)

  12. Corrosion performance of prestressing strands in contact with dissimilar grouts.

    Science.gov (United States)

    2013-01-01

    To improve the corrosion protection provided to prestressing strands, anti-bleed grouts are used to fill voids in post-tensioning : ducts that result from bleeding and shrinkage of older Portland Cement grouts. Environmental differences caused by exp...

  13. Assessing Level and Effectiveness of Corrosion Education in the UAE

    Directory of Open Access Journals (Sweden)

    Hwee Ling Lim

    2012-01-01

    Full Text Available The consequences of corrosion can be minimized by an engineering workforce well trained in corrosion fundamentals and management. Since the United Arab Emirates incurs the second highest cost of corrosion after Saudi Arabia, this paper examined the quality of corrosion education in the UAE. Surveys with academia and industry respondents showed that dedicated corrosion courses and engineering courses that integrated corrosion into the curricula were available in UAE universities, but graduates had insufficient knowledge of corrosion engineering and superficial understanding of corrosion in real-life design contexts. The effectiveness of corrosion education is determined by both competence in corrosion knowledge/skills and availability of resources (faculty and research. Though most departments would not hire new corrosion-specialist faculty, department research efforts and industry partnerships in corrosion research were present. The paper concluded with recommendations for improving knowledge and skills of future engineers in corrosion and enhancing corrosion instruction to better meet industry needs.

  14. Optimum design of the injection duct system of a stenter machine

    Energy Technology Data Exchange (ETDEWEB)

    Juraeva, Makhsuda; Song, Dong Joo [Yeungnam University, Geyongsan (Korea, Republic of); Ryu, Kyung Jin [Ajou Motor College, Boryeong (Korea, Republic of)

    2017-05-15

    Stenter machines are used for drying fabrics in the textile industry and have a heater, injection duct system, and fans inside a chamber. The injection duct system has ducts and air-injecting holes. Plane-type injection duct systems were investigated to obtain uniform airflow at the air-injecting holes. The flow field of the injection duct systems was computed using ANSYS CFX with different heights of the duct end and different shapes for the air-injecting holes. There was a high mass flow rate at the air-injecting holes and high airflow circulation inside both plane-type and mountain-type ducts at the ends. The height of the duct end was varied between 40 mm and 160 mm. The injection duct systems were analyzed with four different shapes of air-injecting holes. The circular and elliptical holes had lower standard deviations of the mass flow rate than other shapes. Relatively uniform mass flow rates were obtained in the plane-type and mountain-type duct systems when the height of the duct end was 40 mm and the shape of the air-injecting holes was circular or elliptical. The developed injection duct systems were improved by obtaining a uniform mass flow rate at the air-injecting holes. A stenter prototype was fabricated with the developed injection duct system to confirm the numerical results. The developed injection duct system had better performance than the original system.

  15. Study for determination of industrial water corrosivity in Kashan Fajre Sepahan Galvanizing Mills during 2005-2006 Iran.

    Science.gov (United States)

    Rabbani, D; Miranzadeh, M B; Motlagh, A Ahmadi

    2008-01-01

    This research was carried out in Kashan Fajre Sepahan Galvanizing mills (KFSGM) for evaluation of water corrosivity during 2005-2006. A total of 18 samples were taken from various points of the water supply system for testing the specific parameters and calculation Langelier Index (LI), Ryznar Index (RI) and Pukorious Index (PI). This research showed that in raw water (sand filter effluent) LI were positive as well as RI and PI were lower than 7 which means that mentioned water is not corrosive. Also LI in treated water by reverse osmosis process was negative and RI and PI were higher than 7, so, this water has corrosive properties. Finally, calculated indexes indicate that according to LI, conditioned water is not corrosive but based on RI and P. this water tend to corrosivity which this findings is compatible with literature review statement. So it is recommended that, for water conditioning addition of preservative chemicals to be continued but at the same time another alternatives such as pH adjustment, air stripping and deoxygenating, control of carbonate concentration and split flow treatment should be studied.

  16. Curved-Duct

    Directory of Open Access Journals (Sweden)

    Je Hyun Baekt

    2000-01-01

    Full Text Available A numerical study is conducted on the fully-developed laminar flow of an incompressible viscous fluid in a square duct rotating about a perpendicular axis to the axial direction of the duct. At the straight duct, the rotation produces vortices due to the Coriolis force. Generally two vortex cells are formed and the axial velocity distribution is distorted by the effect of this Coriolis force. When a convective force is weak, two counter-rotating vortices are shown with a quasi-parabolic axial velocity profile for weak rotation rates. As the rotation rate increases, the axial velocity on the vertical centreline of the duct begins to flatten and the location of vorticity center is moved near to wall by the effect of the Coriolis force. When the convective inertia force is strong, a double-vortex secondary flow appears in the transverse planes of the duct for weak rotation rates but as the speed of rotation increases the secondary flow is shown to split into an asymmetric configuration of four counter-rotating vortices. If the rotation rates are increased further, the secondary flow restabilizes to a slightly asymmetric double-vortex configuration. Also, a numerical study is conducted on the laminar flow of an incompressible viscous fluid in a 90°-bend square duct that rotates about axis parallel to the axial direction of the inlet. At a 90°-bend square duct, the feature of flow by the effect of a Coriolis force and a centrifugal force, namely a secondary flow by the centrifugal force in the curved region and the Coriolis force in the downstream region, is shown since the centrifugal force in curved region and the Coriolis force in downstream region are dominant respectively.

  17. Studies on the impact, detection, and control of microbiology influenced corrosion related to pitting failures in the Russian oil and gas industry. Final CRADA report.

    Energy Technology Data Exchange (ETDEWEB)

    Ehst, D.

    2006-09-30

    The objectives of the Project are: (1) to design effective anti-corrosion preparations (biocides, inhibitors, penetrants and their combinations) for gas- and oil-exploration industries; (2) to study a possibility of development of environmentally beneficial ('green') biocides and inhibitors of the new generation; (3) to develop chemical and microbiological methods of monitoring of sites at risk of corrosion; and (4) to evaluate potentialities in terms of technology, raw materials and material and technical basis to set up a production of effective anti-corrosion preparations of new generation in Russia. During the four years of the project 228 compounds and formulations were synthesized and studied in respect to their corrosion inhibiting activity. A series of compounds which were according to the Bubble tests more efficient (by a factor of 10-100) than the reference inhibitor SXT-1102, some possessing the similar activity or slightly better activity than new inhibitor ??-1154? (company ONDEO/Nalco). Two synthetic routes for the synthesis of mercaptopyrimidines as perspective corrosion inhibitors were developed. Mercaptopyrimidine derivatives can be obtained in one or two steps from cheap and easily available precursors. The cost for their synthesis is not high and can be further reduced after the optimization of the production processes. A new approach for lignin utilization was proposed. Water-soluble derivative of lignin can by transformed to corrosion protective layer by its electropolymerization on a steel surface. Varying lignosulfonates from different sources, as well as conditions of electrooxidation we proved, that drop in current at high anodic potentials is due to electropolymerization of lignin derivative at steel electrode surface. The electropolymerization potential can be sufficiently decreased by an increase in ionic strength of the growing solution. The lignosulfonate electropolymerization led to the considerable corrosion protection

  18. Development of sensors for in-situ monitoring of corrosion and water chemistry parameters for the electric power utility industry

    International Nuclear Information System (INIS)

    Macdonald, D.D.; Pang, J.; Liu, C.; Medina, E.; Villa, J.; Bueno, J.

    1993-01-01

    The in situ monitoring of the chemistry and electrochemistry of aqueous heat transport fluids in thermal (nuclear and fossil) power plants is now considered essential if adequate assessment and close control of corrosion and mass transfer phenomena are to be achieved. Because of the elevated temperatures and pressures involved, new sensor technologies are required that are able to measure key parameters under plant operating conditions for extended periods of time. In this paper, the authors outline a research and development program that is designed to develop practical sensors for use in thermal power plants. The current emphasis is on sensors for measuring corrosion potential, pH, the concentrations of oxygen and hydrogen, and the electrochemical noise generated by corrosion processes at temperatures ranging from ∼250 C to 500 C. The program is currently at the laboratory stage, but testing of prototype sensors in a coal-fired supercritical power plant in Spain will begin shortly

  19. Patent arterial duct

    Directory of Open Access Journals (Sweden)

    Martin Robin P

    2009-07-01

    Full Text Available Abstract Patent arterial duct (PAD is a congenital heart abnormality defined as persistent patency in term infants older than three months. Isolated PAD is found in around 1 in 2000 full term infants. A higher prevalence is found in preterm infants, especially those with low birth weight. The female to male ratio is 2:1. Most patients are asymptomatic when the duct is small. With a moderate-to-large duct, a characteristic continuous heart murmur (loudest in the left upper chest or infraclavicular area is typical. The precordium may be hyperactive and peripheral pulses are bounding with a wide pulse pressure. Tachycardia, exertional dyspnoea, laboured breathing, fatigue or poor growth are common. Large shunts may lead to failure to thrive, recurrent infection of the upper respiratory tract and congestive heart failure. In the majority of cases of PAD there is no identifiable cause. Persistence of the duct is associated with chromosomal aberrations, asphyxia at birth, birth at high altitude and congenital rubella. Occasional cases are associated with specific genetic defects (trisomy 21 and 18, and the Rubinstein-Taybi and CHARGE syndromes. Familial occurrence of PAD is uncommon and the usual mechanism of inheritance is considered to be polygenic with a recurrence risk of 3%. Rare families with isolated PAD have been described in which the mode of inheritance appears to be dominant or recessive. Familial incidence of PAD has also been linked to Char syndrome, familial thoracic aortic aneurysm/dissection associated with patent arterial duct, and familial patent arterial duct and bicuspid aortic valve associated with hand abnormalities. Diagnosis is based on clinical examination and confirmed with transthoracic echocardiography. Assessment of ductal blood flow can be made using colour flow mapping and pulsed wave Doppler. Antenatal diagnosis is not possible, as PAD is a normal structure during antenatal life. Conditions with signs and symptoms of

  20. Corrosion mapping in ducts using the automated ultrasonic technique C-Scan - correlation with results given by pig inspection; Mapeamento de corrosao em dutos atraves da tecnica ultrassonica C-Scan

    Energy Technology Data Exchange (ETDEWEB)

    Feres Filho, Pedro; Moura, Nestor Carlos de [Physical Acoustics South America (PASA), Sao Paulo, SP (Brazil)

    2005-07-01

    In-service inspection has received diverse contributions from technologies and documents with the objective of maximizing equipment availability and minimizing inadequate repairs. Amongst the available technologies, there are the automated ultrasound tests, in the B and C-scan versions. This paper describes an evaluation methodology based on the correlation between the test techniques of instrumented electromagnetic PIG and automated ultrasound, both applied with the purpose of detecting and mapping areas with corrosion in pipes for oil transport. The main objective of the application of the C-scan methodology, in this case, was the measuring and detailing of the corroded area, thus providing an adequate maintenance plan through the substitution or installation of a double gutter. The result demonstrates the correlation between the measurements taken by the PIG and the sizing of the regions done using the C-scan method, consisting of the length, width and thickness values in the points affected by the corrosion. (author)

  1. Particle deposition in ventilation ducts

    Energy Technology Data Exchange (ETDEWEB)

    Sippola, Mark Raymond [Univ. of California, Berkeley, CA (United States)

    2002-09-01

    Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 μm were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on the

  2. EVALUATION OF CORROSION RESISTANCE OF STEEL SHEETS FOR AUTOMOTIVE INDUSTRY WITH THE USE OF THE SPOTFACE TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Alberto Nei Carvalho Costa

    2013-03-01

    Full Text Available Innovation, leading to weight and cost reduction, is a key word concerning the design of steel auto body for auto makers that aim to keep and improve their market share worldwide. On the other hand, auto body life, which is related to the corrosion resistance of the materials employed, should always be considered. The latter has led the auto makers to team up with suppliers to find the best solutions concerning the materials selection. The end result always points towards different sets of steels either zinc-coated or zinc alloyed-coated. Taking all these aspects into consideration, the overall challenge the auto makers face is to mitigate the time required for selection and narrow down the options available. This paper studies the corrosion resistance of several materials applied on steel auto bodies using the technique named spotface, which main advantage is reducing the time required by the traditional scribe to evaluate and compare different materials, when they are submitted either to accelerated or field corrosion testing. Concerning the accelerated corrosion testing, they were performed according to the General Motors do Brasil’s requirements.

  3. Corrosion control. 2. ed.

    International Nuclear Information System (INIS)

    Bradford, S.A.

    2001-01-01

    The purpose of this text is to train engineers and technologists not just to understand corrosion but to control it. Materials selection, coatings, chemical inhibitors, cathodic and anodic protection, and equipment design are covered in separate chapters. High-temperature oxidation is discussed in the final two chapters ne on oxidation theory and one on controlling oxidation by alloying and with coatings. This book treats corrosion and high-temperature oxidation separately. Corrosion is divided into three groups: (1) chemical dissolution including uniform attack, (2) electrochemical corrosion from either metallurgical or environmental cells, and (3) stress-assisted corrosion. Corrosion is logically grouped according to mechanisms rather than arbitrarily separated into different types of corrosion as if they were unrelated. For those university students and industry personnel who approach corrosion theory very hesitantly, this text will present the electrochemical reactions responsible for corrosion summed up in only five simple half-cell reactions. When these are combined on a polarization diagram, which is also explained in detail, the electrochemical processes become obvious. For those who want a text stripped bare of electrochemical theory, several noted sections can be omitted without loss of continuity. However, the author has presented the material in such a manner that these sections are not beyond the abilities of any high school graduate who is interested in technology

  4. Vitellointestinal Duct Anomalies in Infancy

    OpenAIRE

    Kadian, Yogender Singh; Verma, Anjali; Rattan, Kamal Nain; Kajal, Pardeep

    2016-01-01

    Background: Vitellointestinal duct (VID) or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5–9 of intrauterine life. Methods: This is a retrospective analysis of a total of 16 patients of symptomatic remnants of vitellointestinal duct from period of Jan 2009 to May 2013. Results: Male to female ratio (M:F) was 4.3:1 and mean age of presentation was 2 months and their mode of presentation was: paten...

  5. Corrosion in electric transmission lines located in coastal and industrial zones of Chile. (Lat. 32 South degrees; Long. 71 West degrees)

    Energy Technology Data Exchange (ETDEWEB)

    Vera, R.; Orellana, F.; Layana, G.; Cordova, R.; Schrebler, R. [Instituto de Quimica. Universidad Catolica de Valparaiso. Av. Brasil 2950, Casilla 4059, Valparaiso, Chile (Chile)

    1998-12-31

    The atmospheric behavior of copper, aluminium and aluminium 6201 alloy employed in electric transmission lines has been evaluated during two years in order to select those materials that meet the optimal resistance properties toward the environment aggressive conditions. For this purpose, 18 sampling stations were installed at different distances from the sea (60m to 4000 m) for testing the influence of marine environment. Some of these stations also remained at different distances (500 m to 1500m) from an industrial center in order to evaluate the marine-industrial effects in the samples. The corrosion rate (Vc) was determined through weight losses, whereas the morphology and the extent of the attack were analyzed by optical as well as electronic microscopy. Corrosion products were identified by X-ray diffraction. The variation of the mechanical properties of the assayed samples was evaluated through traction resistance measurements. For the aluminium and the aluminium alloy it was found that the Cl and SO{sub 2} present in the atmosphere exerts a synergic effect in Vc increasing. In environments of high SO{sub 2} contents instead, Vc of copper samples diminishes without any significant influence of chlorure present in the atmosphere. (Author)

  6. Corrosion in electric transmission lines located in coastal and industrial zones of Chile. (Lat. 32 South degrees; Long. 71 West degrees)

    International Nuclear Information System (INIS)

    Vera, R.; Orellana, F.; Layana, G.; Cordova, R.; Schrebler, R.

    1998-01-01

    The atmospheric behavior of copper, aluminium and aluminium 6201 alloy employed in electric transmission lines has been evaluated during two years in order to select those materials that meet the optimal resistance properties toward the environment aggressive conditions. For this purpose, 18 sampling stations were installed at different distances from the sea (60m to 4000 m) for testing the influence of marine environment. Some of these stations also remained at different distances (500 m to 1500m) from an industrial center in order to evaluate the marine-industrial effects in the samples. The corrosion rate (Vc) was determined through weight losses, whereas the morphology and the extent of the attack were analyzed by optical as well as electronic microscopy. Corrosion products were identified by X-ray diffraction. The variation of the mechanical properties of the assayed samples was evaluated through traction resistance measurements. For the aluminium and the aluminium alloy it was found that the Cl and SO 2 present in the atmosphere exerts a synergic effect in Vc increasing. In environments of high SO 2 contents instead, Vc of copper samples diminishes without any significant influence of chlorure present in the atmosphere. (Author)

  7. Magnetohydrodynamics in rectangular ducts

    International Nuclear Information System (INIS)

    Lenhart, L.

    1994-04-01

    Magnetohydrodynamic flow in straight ducts or bends is a key issue, which has to be investigated for developing self-cooled liquid metal blankets of fusion reactors. The code presented solves the full set of governing equations and simulates all phenomena of such flows, including inertial effects. The range of application is limited by computer storage only. (orig./WL)

  8. Corrosion fatigue of steels

    International Nuclear Information System (INIS)

    Spaehn, H.; Wagner, G.H.

    1976-01-01

    Corrosion fatigue phenomena can be classified into two main groups according to the electrochemical state of the metal surface in the presence of electrolytes: the active and the passive state with an important sub-group of corrosion fatigue in the unstable passive state. The allowable stress for structures exposed to the conjoint action of corrosion and fatigue is influenced by many factors: kind of media, number of cycles, frequency, mean stress, size, notches, loading mode, alloy composition and mechanical strength. A critical literature review shows contradictory results if a classification by the electrochemical surface state is not applied. Case histories and counter measures illustrate the practical importance of corrosion fatigue in many branches of industry as well as the urgent need for a better knowledge about the mutual influence of the phenomena to get rules by which the engineer can appraise the risk of corrosion fatigue. (orig.) [de

  9. Reciprocity principle in duct acoustics

    Science.gov (United States)

    Cho, Y.-C.

    1979-01-01

    Various reciprocity relations in duct acoustics have been derived on the basis of the spatial reciprocity principle implied in Green's functions for linear waves. The derivation includes the reciprocity relations between mode conversion coefficients for reflection and transmission in nonuniform ducts, and the relation between the radiation of a mode from an arbitrarily terminated duct and the absorption of an externally incident plane wave by the duct. Such relations are well defined as long as the systems remain linear, regardless of acoustic properties of duct nonuniformities which cause the mode conversions.

  10. Corrosion cracking

    International Nuclear Information System (INIS)

    Goel, V.S.

    1985-01-01

    This book presents the papers given at a conference on alloy corrosion cracking. Topics considered at the conference included the effect of niobium addition on intergranular stress corrosion cracking, corrosion-fatigue cracking in fossil-fueled-boilers, fracture toughness, fracture modes, hydrogen-induced thresholds, electrochemical and hydrogen permeation studies, the effect of seawater on fatigue crack propagation of wells for offshore structures, the corrosion fatigue of carbon steels in seawater, and stress corrosion cracking and the mechanical strength of alloy 600

  11. Compact Buried Ducts in a Hot-Humid Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, D. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2016-01-01

    A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval.

  12. EKSTRAHEPATIC BILE DUCT CANCER

    OpenAIRE

    Aleš Tomažič; Dragan Stanisavljevič; Valentin Sojar; Blaž Trotovšek

    2003-01-01

    Background. Malignant strictures involving the bile ducts remain a major challenge in biliary surgery. It is an uncommon cancer. The etiology is unknown, most cases are sporadic, but several conditions confer an incrised risk of developing cholangiocarcinoma.Clinical presentation and preoperative evaluation. The early simptoms are nonspecific. In the past computed tomography, percutaneous transhepatic cholangiography and angiography were considered standard investigations, but currently magne...

  13. Noise suppression in duct

    International Nuclear Information System (INIS)

    Ahmed, A.; Barfeh, M.A.G.

    2001-01-01

    In air-conditioning system the noise generated by supply fan is carried by conditioned air through the ductwork. The noise created in ductwork run may be transmission, regenerative and ductborne. Transmission noise is fan noise, regenerative noise is due to turbulence in flow and ductborne noise is the noise radiating from duct to surroundings. Some noise is attenuated in ducts also but if noise level is high then it needs to be attenuated. A simple mitre bend can attenuate-noise. This principle is extended to V and M-shape ducts with inside lining of fibreglass, which gave maximum attenuation of 77 dB and 62 dB respectively corresponding to 8 kHz frequency as compared to mitre, bend giving maximum 18 dB attenuation. Sound level meter measured sound levels with octave band filter and tests were conducted in anechoic room. A V-shape attenuator can be used at fan outlet and high frequency noise can be minimized greatly. (author)

  14. Zircaloy-4 corrosion in PWR's

    International Nuclear Information System (INIS)

    Fyfitch, S.; Smalley, W.R.; Roberts, E.

    1985-01-01

    Zircaloy-4 waterside corrosion has been studied extensively in the nuclear industry for a number of years. Following the early crud-related corrosion failures in the Saxton test reactor, Westinghouse undertook numerous programs to minimize crud deposition on fuel rods in power reactors through primary coolant chemistry control. Modern plants today are operating with improved coolant chemistry guidelines, and crud deposition levels are very low in proportion to earlier experience. Zircaloy-4 corrosion under a variety of coolant chemistry, heat flux and exposure conditions has been studied extensively. Experience to date, even in relatively high coolant temperature plants, has indicated that -for both fuel cladding and structural components- Zircaloy-4 waterside corrosion performance has been excellent. Recognizing future industry trends, however, which will result in Zircaloy-4 being subjected to ever increasing corrosion duties, Westinghouse will continue accumulating Zircaloy-4 corrosion experience in large power plants. 13 refs.

  15. Nuclear corrosion science and engineering

    CERN Document Server

    2012-01-01

    Understanding corrosion mechanisms, the systems and materials they affect, and the methods necessary for accurately measuring their incidence is of critical importance to the nuclear industry for the safe, economic and competitive running of its plants. This book reviews the fundamentals of nuclear corrosion. Corrosion of nuclear materials, i.e. the interaction between these materials and their environments, is a major issue for plant safety as well as for operation and economic competitiveness. Understanding these corrosion mechanisms, the systems and materials they affect, and the methods to accurately measure their incidence is of critical importance to the nuclear industry. Combining assessment techniques and analytical models into this understanding allows operators to predict the service life of corrosion-affected nuclear plant materials, and to apply the most appropriate maintenance and mitigation options to ensure safe long term operation. This book critically reviews the fundamental corrosion mechani...

  16. Corrosion protection and control using nanomaterials

    CERN Document Server

    Cook, R

    2012-01-01

    This book covers the use of nanomaterials to prevent corrosion. The first section deals with the fundamentals of corrosion prevention using nanomaterials. Part two includes a series of case studies and applications of nanomaterials for corrosion control.$bCorrosion is an expensive and potentially dangerous problem in many industries. The potential application of different nanostructured materials in corrosion protection, prevention and control is a subject of increasing interest. Corrosion protection and control using nanomaterials explores the potential use of nanotechnology in corrosion control. The book is divided into two parts. Part one looks at the fundamentals of corrosion behaviour and the manufacture of nanocrystalline materials. Chapters discuss the impact of nanotechnology in reducing corrosion cost, and investigate the influence of various factors including thermodynamics, kinetics and grain size on the corrosion behaviour of nanocrystalline materials. There are also chapters on electrodeposition ...

  17. Corrosion engineering

    Energy Technology Data Exchange (ETDEWEB)

    Fontana, M.G.

    1986-01-01

    This book emphasizes the engineering approach to handling corrosion. It presents corrosion data by corrosives or environments rather than by materials. It discusses the corrosion engineering of noble metals, ''exotic'' metals, non-metallics, coatings, mechanical properties, and corrosion testing, as well as modern concepts. New sections have been added on fracture mechanics, laser alloying, nuclear waste isolation, solar energy, geothermal energy, and the Statue of Liberty. Special isocorrosion charts, developed by the author, are introduced as a quick way to look at candidates for a particular corrosive.

  18. Rare bile duct anomaly: B3 duct draining to gallbladder

    Directory of Open Access Journals (Sweden)

    Seung Eun Lee

    2016-01-01

    Full Text Available A 10-year-old girl presented with recurrent right upper abdominal pain and dyspepsia. Magnetic resonance cholangiopancreatography revealed a dilated common channel of intrahepatic bile duct of segment 3 (B3 and segment 4 (B4 drained into the gallbladder directly. The patient underwent laparoscopic cholecystectomy and Roux-en Y hepaticojejunostomy (B3-jejunostomy. Among the anatomical variability of the biliary system, the cholecystohepatic ducts are controversial in existence and incidence. We report a very rare variant of a cholecystohepatic duct in which the B3 duct drained into gallbladder directly and to the best of our knowledge this is the first report.

  19. Development plan of austenitic Fe and Ni based alloys with improved corrosion resistance to sulfuric acid and HI fluids of industrial processes

    International Nuclear Information System (INIS)

    Hirota, Noriaki; Iwatsuki, Jin; Imai, Yoshiyuki; Yan, Xing L.

    2017-12-01

    In this study, austenitic Fe based alloys and Ni based alloys was developed as candidate structural materials for equipment operated in sulfuric acid and hydrogen iodide (HI) environment, which exists in various industrial processes including iodine-sulfur (IS) hydrogen production process and geothermal power generation process. The objectives of the study are to achieve the corrosion resistance performance sufficient under the working condition of these processes and to overcome the practical scale-up difficulty of the ceramic (SiC) material that is presently used in the processes due to the manufacturing size limitation of the ceramic. The chemical composition development plan for the austenitic Fe based alloys is threefold: reinforcement of matrix by addition of Cu and Ta, strength compensation of the surface film by addition of Si and Ti, and prevention of peeling of surface oxide by addition of rare earth elements. Because addition of Cu and Si is known to reduce the ductility of the material and thus manufacturability of the component, it is important to determine the allowable amount of each element to be added. On the other hand, the chemical composition development plan for the Ni based alloys is reinforcement of matrix by addition of Mo, W and Ta, strength compensation of the surface film by addition of Ti, and prevention of peeling of surface oxide by addition of rare earth elements. In particular, the addition of Mo and W to the Ni based alloy is expected to be effective in preventing dimensional deviation of structures from increasing during heating and cooling of process equipment. Various material specimens will be fabricated based on the above chemical composition development plans and tests on these specimens will then be carried out to confirm the corrosion resistance performance under the fluid conditions simulating each industrial process. (author)

  20. Radiation resistant ducted superconductive coil

    International Nuclear Information System (INIS)

    Schleich, A.

    1976-01-01

    The radiation-resistant ducted superconductive coil consists of a helically wound electrical conductor constituted by an electrically conductive core of superconductive material provided with a longitudinally extending cooling duct. The core is covered with a layer of inorganic insulating material and the duct is covered by an electrically conductive metallic gas-tight sheath. The metallic sheaths on adjacent turns of the coil are secured together. 2 Claims, 4 Drawing Figures

  1. Duct having oscillatory side wall

    Science.gov (United States)

    Sprouse, Kenneth M.

    2018-04-03

    A pump system includes a particulate consolidator pump that has a pump outlet. A duct is coupled to the pump outlet. The duct has a wall that is coupled with an oscillator. The oscillator is operable to oscillate the wall at a controlled frequency. The controlled frequency is selected with respect to breaking static bridging of particulate in the duct due, at least in part, to consolidation of the particulate from a downstream check valve.

  2. Evaluation of a high-temperature burner-duct-recuperator system

    Science.gov (United States)

    1990-07-01

    The U.S. Department of Energy's (DOE) Office of Industrial Technologies (OIT) sponsors research and development (R and D) to improve the energy efficiency of American industry and to provide for fuel flexibility. OIT has funded a multiyear R and D project by the Babcock and Wilcox Company (B and W) to design, fabricate, field test, and evaluate a high-temperature burner-duct-recuperator (HTBDR) system. This ceramic-based recuperator system recovers waste heat from the corrosive, high-temperature (2170 F) flue gas stream of a steel soaking pit to preheat combustion air to as high as 1700 F. The preheated air is supplied to a high-temperature burner. The B and W R and D program, which is now complete, involved several activities, including selecting and evaluating ceramic materials, designing the system, and developing and evaluating the prototype. In addition, a full-scale unit was tested at a B and W steel soaking pit. The full-scale system consisted of a modular single-stage ceramic recuperator, a conventional two-pass metallic recuperator, a high-temperature burner, fans, insulated ducting, and associated controls and instrumentation. The metallic recuperator preheated combustion air to about 750 F before it passed to the ceramic module. This technical case study describes the DOE/B and W recuperator project and highlights the field tests of the full-scale recuperator system. The document makes results of field tests and data analysis available to other researchers and private industry. It discusses project status, summarizes field tests, and reviews the potential effects the technology will have on energy use and system economics.

  3. Assessing Level and Effectiveness of Corrosion Education in the UAE

    OpenAIRE

    Lim, Hwee Ling

    2012-01-01

    The consequences of corrosion can be minimized by an engineering workforce well trained in corrosion fundamentals and management. Since the United Arab Emirates incurs the second highest cost of corrosion after Saudi Arabia, this paper examined the quality of corrosion education in the UAE. Surveys with academia and industry respondents showed that dedicated corrosion courses and engineering courses that integrated corrosion into the curricula were available in UAE universities, but graduates...

  4. Corrosion '98: 53. annual conference and exposition, proceedings

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    This conference was divided into the following sections: Corrosion in Gas Treating; Problems and Solutions in Commercial Building Water Systems; Green Corrosion/Scale Inhibitors; Atmospheric Corrosion; AIRPOL Update/98; Rubber Lining--Answers to Many Problems; Interference Problems; Environmental Assisted Cracking: Fundamental Research and Industrial Applications; Corrosion in Nuclear Systems; New Developments in Scale and Deposit Control; Corrosion and Corrosion Protection in the Transportation Industries; What's All the Noise About--Electrochemical That Is; Refining Industry Corrosion; Corrosion Problems in Military Hardware: Case Histories, Fixes and Lessons Learned; Cathodic Protection Test Methods and Instrumentation for Underground and On-grade Pipelines and Tanks; Recent Developments in Volatile Corrosion Inhibitors; Corrosion in Supercritical Fluids; Microbiologically Influenced Corrosion; Advances in Understanding and Controlling CO 2 Corrosion; Managing Corrosion with Plastics; Material Developments for Use in Exploration and Production Environments; Corrosion in Cold Regions; The Effect of Downsizing and Outsourcing on Cooling System Monitoring and Control Practices; New Developments in Mechanical and Chemical Industrial Cleaning; Mineral Scale Deposit Control in Oilfield Related Operations; Biocides in Cooling Water; Corrosion and Corrosion Control of Reinforced Concrete Structures; Materials Performance for Fossil Energy Conversion Systems; Marine corrosion; Thermal Spray--Coating and Corrosion Control; Flow Effects on Corrosion in Oil and Gas Production; Corrosion Measurement Technologies; Internal Pipeline Monitoring--Corrosion Monitoring, Intelligent Pigging and Leak Detection; Cathodic Protection in Natural Waters; Corrosion in Radioactive Liquid Waste Systems; On-line Hydrogen Permeation Monitoring Equipment and Techniques, State of the Art; Water Reuse and Recovery; Performance of Materials in High Temperature Environments; Advances in Motor

  5. Carbon Dioxide Corrosion:

    DEFF Research Database (Denmark)

    Fosbøl, Philip Loldrup

    2008-01-01

    CO2 corrosion is a general problem in the industry and it is expensive. The focus of this study is an oil gas production related problem. CO2 corrosion is observed in offshore natural gas transportation pipelines. A general overview of the problem is presented in chapter 1. The chemical system...... with the basic thermodynamics of electrolytes in chapter 2, the extension and general description of electrolyte mass transport in chapter 3, and the electrochemical kinetics of corrosion in chapter 4. A literature overview of CO2 corrosion is shown in chapter 5 and possible extensions of the models...... and validated against heat capacity data. The model is also fitted to experimental data produced and shown in chapter 8 for SLE in the Na2CO3-NaHCO3-MEG-H2O system. The application of the above model is shown in chapter 9. Here the thermodynamic correction factors are calculated. These show how the diffusion...

  6. Transcystic duct treatment of common bile duct stones

    International Nuclear Information System (INIS)

    Amberg, J.R.; Chun, G.

    1981-01-01

    Successful removal of 2 retained common bile duct stones following cholecystostomy is described. With the use of the steerable catheter and the wire basket, one stone was crushed and the second was extracted in retrograde fashion through the cystic duct and gallbladder. (orig.)

  7. Corrosion of reinforcement induced by environment containing ...

    Indian Academy of Sciences (India)

    Unknown

    carbonation and chlorides causing corrosion of steel reinforcement. ... interesting and important when the evaluation of the service life of the ... preferably in the areas of industrial and transport activities. ... For controlling the embedded corrosion sensors, elec- .... danger of corrosion of reinforcement seems to be more.

  8. Stress corrosion and corrosion fatigue crack growth monitoring in metals

    International Nuclear Information System (INIS)

    Senadheera, T.; Shipilov, S.A.

    2003-01-01

    Environmentally assisted cracking (including stress corrosion cracking and corrosion fatigue) is one of the major causes for materials failure in a wide variety of industries. It is extremely important to understand the mechanism(s) of environmentally assisted crack propagation in structural materials so as to choose correctly from among the various possibilities-alloying elements, heat treatment of steels, parameters of cathodic protection, and inhibitors-to prevent in-service failures due to stress corrosion cracking and corrosion fatigue. An important step towards understanding the mechanism of environmentally assisted crack propagation is designing a testing machine for crack growth monitoring and that simultaneously provides measurement of electrochemical parameters. In the present paper, a direct current (DC) potential drop method for monitoring crack propagation in metals and a testing machine that uses this method and allows for measuring electrochemical parameters during stress corrosion and corrosion fatigue crack growth are described. (author)

  9. Propagation of sound waves in ducts

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    2000-01-01

    Plane wave propagation in ducts with rigid walls, radiation from ducts, classical four-pole theory for composite duct systems, and three-dimentional waves in wave guides of various cross-sectional shape are described.......Plane wave propagation in ducts with rigid walls, radiation from ducts, classical four-pole theory for composite duct systems, and three-dimentional waves in wave guides of various cross-sectional shape are described....

  10. Fatigue life prediction of oil ducts under service loads

    Energy Technology Data Exchange (ETDEWEB)

    Meggiolaro, Marco A.; Castro, Jaime T.P. [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil)

    2003-07-01

    A methodology to calculate the residual initiation and propagation lives of fatigue cracks in oil pipelines with corrosion-like defects is proposed and applied to predict the residual life of an old duct made of API 5L Gr. B steel, in service for more than 40 years. Since its inauguration, this pipeline has carried several heated products under variable temperatures and pressures. The calculated (nominal) service stresses are very high, due to thermal loads that induce significant bending in curved parts of the duct, with peaks close to the yield strength of the steel. The elastic- plastic fatigue damage at a notch or a corrosion pit root is calculated using the {epsilon}N method, and the effects of surface semi-elliptical cracks in its internal (or external) wall is studied considering appropriate stress intensity factor expressions and the actual service loads. In the presence of surface flaws associated to stress concentration factors of the order of three, a fatigue crack likely will initiate in the pipeline. However, if these surface cracks are small compared to the duct wall thickness, their predicted propagation rates are very low. (author)

  11. EUROCORR 2007 - The European corrosion congress - Progress by corrosion control. Book of Abstracts

    International Nuclear Information System (INIS)

    2007-01-01

    This book of abstracts contains lectures, workshops and posters which were held on the European Corrosion Congress 2007 in Freiburg (Germany). The main topics of the sessions and posters are: 1. Corrosion and scale inhibition; 2. Corrosion by hot gases and combustion products; 3. Nuclear corrosion; 4. Environment sensitive fracture; 5. Surface Science; 6. Physico-chemical methods of corrosion testing; 7. Marine corrosion; 8. Microbial corrosion; 9. Corrosion of steel in concrete; 10. Corrosion in oil and gas production; 11. Coatings; 12. Corrosion in the refinery industry; 13. Cathodic protection; 14. Automotive Corrosion; 15. Corrosion of polymer materials. The main topics of the workshops are: 1. High temperature corrosion in the chemical, refinery and petrochemical industries; 2. Bio-Tribocorrosion; 3. Stress corrosion cracking in nuclear power plants; 4. Corrosion monitoring in nuclear systems; 5. Cathodic protection for marine and offshore environments; 6. Self-healing properties of new surface treatments; 7. Bio-Tribocorrosion - Cost 533/Eureka-ENIWEP-Meeting; 8. Drinking water systems; 9. Heat exchangers for seawater cooling

  12. Corrosion Cost and Corrosion Map of Korea - Based on the Data from 2005 to 2010

    International Nuclear Information System (INIS)

    Kim, Y. S.; Lim, H. K.; Kim, J. J.; Hwang, W. S.; Park, Y. S.

    2011-01-01

    Corrosion of metallic materials occurs by the reaction with corrosive environment such as atmosphere, marine, soil, urban, high temperature etc. In general, reduction of thickness and cracking and degradation are resulted from corrosion. Corrosion in all industrial facilities and infrastructure causes large economic losses as well as a large number of accidents. Economic loss by corrosion has been reported to be nearly 1-6% of GNP or GDP. In order to reduce corrosion damage of industrial facilities, corrosion map as well as a systematic investigation of the loss of corrosion in each industrial sector is needed. The Corrosion Science Society of Korea in collaboration with 15 universities and institutes has started to survey on the cost of corrosion and corrosion map of Korea since 2005. This work presents the results of the survey on cost of corrosion by Uhlig, Hoar, and input-output methods, and the evaluation of atmospheric corrosion rate of carbon steel, weathering steel, galvanized steel, copper, and aluminum in Korea. The total corrosion cost was estimated in terms of the percentage of the GDP of industry sectors and the total GDP of Korea. According to the result of Input/output method, corrosion cost of Korea was calculated as 2.9% to GDP (2005). Time of wetness was shown to be categories 3 to 4 in all exposure areas. A definite seasonal difference was observed in Korea. In summer and fall, time of wetness was higher than in other seasons. Because of short exposure period (12 months), significant corrosion trends depending upon materials and exposure corrosion environments were not revealed even though increased mass loss and decreased corrosion rate by exposure time

  13. The impact of duct-to-duct interaction on the hex duct dilation

    International Nuclear Information System (INIS)

    Lee, M.J.; Chang, L.K.; Lahm, C.E.; Porter, D.L.

    1992-01-01

    Dilation of the hex duct is an important factor in the operational lifetime of fuel subassemblies in liquid metal fast reactors. It is caused primarily by the irradiation-enhanced creep and void swelling of the hex duct material. Excessive dilation may jeopardize subassembly removal from the core or cause a subassembly storage problem where the grid size of the storage basket is limited. Dilation of the hex duct in Experimental Breeder Reactor II (EBR-II) limits useful lifetime because of these storage basket limitations. It is, therefore, important to understand the hex duct dilation behavior to guide the design and in-core management of fuel subassemblies in a way that excessive duct deformation can be avoided. To investigate the dilation phenomena, finite-element models of the hex duct have been developed. The inelastic analyses were performed using the structural analysis code, ANSYS. Both Type 316 and D9 austenitic stainless steel ducts are considered. The calculated dilations are in good agreement with profilometry measurements made after irradiation. The analysis indicates that subassembly interaction is an important parameter in addition to neutron fluence and temperature in determining hex duct dilation. 5 refs

  14. Thermal performance test of the hot gas ducts of HENDEL

    International Nuclear Information System (INIS)

    Hishida, M.; Kunitomi, K.; Ioka, I.; Umenishi, K.; Tanaka, T.; Shimomura, H.; Sanokawa, K.

    1984-01-01

    A hot gas duct provided with internal thermal insulation is to be used for high-temperature gas-cooled reactors (HTGR). This type of hot gas duct has not been used so far in industrial facilities, and only a couple of tests on such a large-scale model of a hot gas duct have been conducted. The present report deals with the results of the thermal performance of the single tube type hot gas ducts which are installed as parts of a helium engineering demonstration loop (HENDEL). Uniform temperature and heat flux distribution at the surface of the duct were observed, the experimental correlations being obtained for the effective thermal conductivity of the internal thermal insulation layer. The measured temperature distribution of the pressure tube was in good agreement with the calculation by a TRUMP heat transfer computer code. The temperature distribution of the inner tube of the co-axial hot gas duct was evaluated and no hot spot was detected. These results would be very valuable for the design and development of HTGR. (orig.)

  15. Microbiologically induced corrosion

    International Nuclear Information System (INIS)

    Stein, A.A.

    1988-01-01

    Biological attack is a problem that can affect all metallic materials in a variety of environments and systems. In the power industry, corrosion studies have focused on condensers and service water systems where slime, barnacles, clams, and other macro-organisms are easily detected. Efforts have been made to eliminate the effect of these organisms through the use of chlorination, backflushing, organic coating, or thermal shock. The objective is to maintain component performance by eliminating biofouling and reducing metallic corrosion. Recently, corrosion of power plant components by micro-organisms (bacteria) has been identified even in very clean systems. A system's first exposure to microbiologically induced corrosion (MIC) occurs during its first exposure to an aqueous environment, such as during hydrotest or wet layup. Corrosion of buried pipelines by sulfate-reducing bacteria has been studied by the petrochemical industry for years. This paper discusses various methods of diagnosing, monitoring, and controlling MIC in a variety of systems, as well as indicates areas where further study is needed

  16. Proceedings of the sixteenth national congress on corrosion control

    International Nuclear Information System (INIS)

    2012-01-01

    The congress was a forum for presenting the industrial problems and ideas derived from current research and various topics on corrosion. The conference thereon was focussed on corrosion degradation phenomena in various industries and mitigative actions or solutions to the issues of corrosion. The corrosion problems in ports, petroleum, chemical and fertilizer, power, steel, nuclear, shipping, defence, construction, and refinery industries are discussed. Papers relevant to INIS are indexed separately

  17. Development of analytical procedures for the determination of hexavalent chromium in corrosion prevention coatings used in the automotive industry.

    Science.gov (United States)

    Séby, F; Castetbon, A; Ortega, R; Guimon, C; Niveau, F; Barrois-Oudin, N; Garraud, H; Donard, O F X

    2008-05-01

    The European directive 2000/53/EC limits the use of Cr(VI) in vehicle manufacturing. Although a maximum of 2 g of Cr(VI) was authorised per vehicle for corrosion prevention coatings of key components, since July 2007 its use has been prohibited except for some particular applications. Therefore, the objective of this work was to develop direct analytical procedures for Cr(VI) determination in the different steel coatings used for screws. Instead of working directly with screws, the optimisation of the procedures was carried out with metallic plates homogeneously coated to improve the data comparability. Extraction of Cr(VI) from the metallic parts was performed by sonication. Two extraction solutions were tested: a direct water extraction solution used in standard protocols and an ammonium/ammonia buffer solution at pH 8.9. The extracts were further analysed for Cr speciation by high-performance liquid chromatography (HPLC) inductively coupled plasma (ICP) atomic emission spectrometry or HPLC ICP mass spectrometry depending on the concentration level. When possible, the coatings were also directly analysed by solid speciation techniques (X-ray photoelectron spectroscopy, XPS, and X-ray absorption near-edge structure, XANES) for validation of the results. Very good results between the different analytical approaches were obtained for the sample of coating made up of a heated paint containing Zn, Al and Cr when using the extracting buffer solution at pH 8.9. After a repeated four-step extraction procedure on the same portion test, taking into account the depth of the surface layer reached, good agreement with XPS and XANES results was obtained. In contrast, for the coatings composed of an alkaline Zn layer where Cr(VI) and Cr(III) are deposited, only the extraction procedure using water allowed the detection of Cr(VI). To elucidate the Cr(VI) reduction during extraction at pH 8.9, the reactivity of Cr(VI) towards different species of Zn generally present in the

  18. Optimising corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.; Andersen, A.

    2002-01-01

    A three-year project - financially supported by the Nordic Industrial Fund - on monitoring of corrosion in district heating systems has been initiated with participation of researchers and industrial partners in Denmark, Finland, Iceland, Norway and Sweden. The primary objective of the project...... is to improve the quality control in district heating systems by corrosion monitoring. In Danish systems electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR), high-sensitive electrical resistance (ER) technology, crevice corrosion probes, as well as weight loss coupons...

  19. Vitellointestinal Duct Anomalies in Infancy.

    Science.gov (United States)

    Kadian, Yogender Singh; Verma, Anjali; Rattan, Kamal Nain; Kajal, Pardeep

    2016-01-01

    Vitellointestinal duct (VID) or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5-9 of intrauterine life. This is a retrospective analysis of a total of 16 patients of symptomatic remnants of vitellointestinal duct from period of Jan 2009 to May 2013. Male to female ratio (M:F) was 4.3:1 and mean age of presentation was 2 months and their mode of presentation was: patent VID in 9 (56.25%) patients, umbilical cyst in 2(12.25%), umbilical granuloma in 2 (12.25%), and Meckel diverticulum as content of hernia sac in obstructed umbilical hernia in 1 (6.25%) patient. Two patients with umbilical fistula had severe electrolyte disturbance and died without surgical intervention. Persistent VID may have varied presentations in infancy. High output umbilical fistula and excessive bowel prolapse demand urgent surgical intervention to avoid morbidity and mortality.

  20. Recent Natural Corrosion Inhibitors for Mild Steel: An Overview

    Directory of Open Access Journals (Sweden)

    Marko Chigondo

    2016-01-01

    Full Text Available Traditionally, reduction of corrosion has been managed by various methods including cathodic protection, process control, reduction of the metal impurity content, and application of surface treatment techniques, as well as incorporation of suitable alloys. However, the use of corrosion inhibitors has proven to be the easiest and cheapest method for corrosion protection and prevention in acidic media. These inhibitors slow down the corrosion rate and thus prevent monetary losses due to metallic corrosion on industrial vessels, equipment, or surfaces. Inorganic and organic inhibitors are toxic and costly and thus recent focus has been turned to develop environmentally benign methods for corrosion retardation. Many researchers have recently focused on corrosion prevention methods using green inhibitors for mild steel in acidic solutions to mimic industrial processes. This paper provides an overview of types of corrosion, corrosion process, and mainly recent work done on the application of natural plant extracts as corrosion inhibitors for mild steel.

  1. Corrosion Engineering.

    Science.gov (United States)

    White, Charles V.

    A description is provided for a Corrosion and Corrosion Control course offered in the Continuing Engineering Education Program at the General Motors Institute (GMI). GMI is a small cooperative engineering school of approximately 2,000 students who alternate between six-week periods of academic study and six weeks of related work experience in…

  2. Corrosion Monitoring System

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Russ Braunling

    2004-10-31

    The Corrosion Monitoring System (CMS) program developed and demonstrated a continuously on-line system that provides real-time corrosion information. The program focused on detecting pitting corrosion in its early stages. A new invention called the Intelligent Ultrasonic Probe (IUP) was patented on the program. The IUP uses ultrasonic guided waves to detect small defects and a Synthetic Aperture Focusing Technique (SAFT) algorithm to provide an image of the pits. Testing of the CMS demonstrated the capability to detect pits with dimensionality in the sub-millimeter range. The CMS was tested in both the laboratory and in a pulp and paper industrial plant. The system is capable of monitoring the plant from a remote location using the internet.

  3. Investigation of the Degradation Mechanisms of Particulate Reinforced Epoxy Coatings and Zinc-Rich Coatings Under an Erosion and Corrosion Environment for Oil and Gas Industry Applications

    Science.gov (United States)

    Wang, Dailin

    During oil and gas production and transportation, the presence of an oil-sand slurry, together with the presence of CO2, H2S, oxygen, and seawater, create an erosive/abrasive and corrosive environment for the interior surfaces of undersea pipelines transporting oil and gas from offshore platforms. Erosion/wear and corrosion are often synergic processes leading to a much greater material loss of pipeline cross-section than that caused by each individual process alone. Both organic coatings and metallic sacrificial coatings have been widely employed to provide protection to the pipeline steels against corrosion through barrier protection and cathodic protection, and these protection mechanisms have been well studied. However, coating performance under the synergic processes of erosion/wear and corrosion have been much less researched and coating degradation mechanisms when erosion/wear and corrosion are both going on has not been well elucidated. In the work presented in this dissertation, steel panels coated with filler reinforced epoxy coatings and carbon nanotubes (CNTs) reinforced zinc-rich coatings have been evaluated under erosion/wear followed by an exposure to a corrosive environment. Electrochemical tests and material characterization methods have been applied to study the degradation mechanisms of the coatings during the tests and coating degradation mechanisms have been proposed. While organic coatings with a lower amount of filler particles provided better protection in a corrosive environment alone and in solid particle impingement erosion testing alone, organic coatings with a higher amount of filler particles showed better performance during wear testing alone. A higher amount of filler particles was also beneficial in providing protection against wear and corrosion environment, and erosion and corrosion environment. Coating thickness played a significant role in the barrier properties of the coatings under both erosion and corrosion tests. When the

  4. Assessment of corrosion in the flue gas cleaning system using on-line monitoring

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Vendelbo Nielsen, Lars; Berggreen Petersen, Michael

    2015-01-01

    Amager unit 1 is a 350 MW multifuel suspension-fired plant commissioned in 2009 to fire biomass (straw and wood pellets). Increasing corrosion problems in the flue gas cleaning system were observed in the gas-gas preheater (GAFO), the booster fan and flue gas ducts. Chlorine containing corrosion ...

  5. Corrosion and Wear Analysis in Marine Transport Constructions

    OpenAIRE

    Urbahs, A; Savkovs, K; Rijkuris, G; Andrejeva, D

    2018-01-01

    Corrosion is one of the most common naturally occurring processes studied by thermodynamics, which includes oxidation process, metal disruption, and its chemical and electrochemical effects under environmental influence. Corrosion of metal and equipment accounts for a considerable proportion of total corrosion losses, thus providing the impetus for further investigation and developments related to corrosion protection in order to provide transport systems and industry with corrosion preventiv...

  6. Practical use of CFD for air conditioning duct and defroster designing; Kucho duct defroster no CFD sekkei katsuyo

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, K [Daihatsu Motor Co. Ltd., Osaka (Japan)

    1997-10-01

    The automobile industry have made effort to shorten the development period. Recently CFD (Computational Fluid Dynamics) on initial design stage becomes use for improvement of development efficiency. Although the practical guidepost (computed examples) for air conditioning duct and defroster are a little reported. This report presents how to optimize and standardize the calculational methods, calculational grid, boundary conditions for air conditioning duct and defroster nozzle in the practical use. Also we tried the discontinuous interface grid and the solution adaptive method. 2 refs., 17 figs.

  7. A Review of Field Corrosion Control and Monitoring Techniques of ...

    African Journals Online (AJOL)

    OLUWASOGO

    corrosion attack and eventual failure of pipelines within oil and gas industry has been classified ... pipelines' commissioning which include design, material selection, protective ..... analyses after certain period to obtain corrosion information.

  8. Integration of a nonmetallic electrostatic precipitator and a wet scrubber for improved removal of particles and corrosive gas cleaning in semiconductor manufacturing industries.

    Science.gov (United States)

    Kim, Hak-Joon; Han, Bangwoo; Kim, Yong-Jin; Yoa, Seok-Jun; Oda, Tetsuji

    2012-08-01

    To remove particles in corrosive gases generated by semiconductor industries, we have developed a novel non-metallic, two-stage electrostatic precipitator (ESP). Carbon brush electrodes and grounded carbon fiber-reinforced polymer (CFRP) form the ionization stage, and polyvinyl chloride collection plates are used in the collection stage of the ESP The collection performance of the ESP downstream of a wet scrubber was evaluated with KC1, silica, and mist particles (0.01-10 pm), changing design and operation parameters such as the ESP length, voltage, and flow rate. A long-term and regeneration performance (12-hr) test was conducted at the maximum operation conditions of the scrubber and ESP and the performance was then demonstrated for 1 month with exhaust gases from wet scrubbers at the rooftop of a semiconductor manufacturing plant in Korea. The results showed that the electrical and collection performance of the ESP (16 channels, 400x400 mm2) was maintained with different grounded plate materials (stainless steel and CFRP) and different lengths of the ionization stage. The collection efficiency of the ESP at high air velocity was enhanced with increases in applied voltages and collection plate lengths. The ESP (16 channels with 100 mm length, 400x400 mm2x540 mm with a 10-mm gap) removed more than 90% of silica and mistparticles with 10 and 12 kV applied to the ESPat the air velocity of 2 m/s and liquid-to-gas ratio of 3.6 L/m3. Decreased performance after 13 hours ofcontinuous operation was recovered to the initial performance level by 5 min of water washing. Moreover during the 1-month operation at the demonstration site, the ESP showed average collection efficiencies of 97% based on particle number and 92% based on total particle mass, which were achieved with a much smaller specific corona power of 0.28 W/m3/hr compared with conventional ESPs.

  9. Proceedings of the International Congress (12th), Corrosion Control for Low-Cost Reliability, Held in Houston, Texas on September 19 -24, 1993. Volume 6. Electric Power Industry

    Science.gov (United States)

    1993-09-24

    700 A. Perkins ........................................................................... 882 308 Dissolution and Precipitation Phenomena in...Ohsumi ............................... 4060 135 In-Situ Gravimetry of Corrosion of Iron Thin Films Combined with Surface Analytical Techniques M . Seo

  10. Phyllanthus muellerianus and C6H15NO3 synergistic effects on 0.5 M H2SO4-immersed steel-reinforced concrete: Implication for clean corrosion-protection of wind energy structures in industrial environment

    Science.gov (United States)

    Okeniyi, Joshua Olusegun; Omotosho, Olugbenga Adeshola; Popoola, Abimbola Patricia Idowu; Loto, Cleophas Akintoye

    2016-07-01

    This paper investigates Phyllanthus muellerianus leaf-extract and C6H15NO3 (triethanolamine: TEA) synergistic effects on reinforcing-steel corrosion-inhibition and the compressive-strength of steel-reinforced concrete immersed in 0.5 M H2SO4. This is to assess suitability of the synergistic admixture usage for wind-energy steel-reinforced concrete structures designed for industrial environments. Steel-reinforced concrete specimens were admixed with individual and synergistic designs of Phyllanthus muellerianus leaf-extract and C6H15NO3 admixtures and immersed in the 0.5 M H2SO4. Electrochemical monitoring of corrosion potential, as per ASTM C876-91 R99, and corrosion current were obtained and statistically analysed, as per ASTM G16-95 R04, for modelling noise resistance. Post-immersion compressive-strength testing then followed, as per ASTM C39/C39M-03, for detailing the admixture effect on load-bearing strength of the steel-reinforced concrete specimens. Results showed that while individual Phyllanthus muellerianus leaf-extract concentrations exhibited better inhibition-efficiency performance than C6H15NO3, synergistic additions of C6H15NO3 to Phyllanthus muellerianus leaf-extract improved steel-rebar corrosion-inhibition. Thus, 6 g Phyllanthus muellerianus + 2 g C6H15NO3 synergistically improved inhibition-efficiency to η = 84.17%, from η = 55.28% by the optimal chemical or from η = 74.72% by the optimal plant-extract admixtures. The study also established that improved compressive strength of steel-reinforced concrete with acceptable inhibition of the steel-rebar corrosion could be attained through optimal combination of the Phyllanthus muellerianus leaf-extract and C6H15NO3 admixtures.

  11. Industry

    International Nuclear Information System (INIS)

    Schindler, I.; Wiesenberger, H.

    2001-01-01

    This chapter of the environmental control report deals with the environmental impact of the industry in Austria. It gives a review of the structure and types of the industry, the legal framework and environmental policy of industrial relevance. The environmental situation of the industry in Austria is analyzed in detail, concerning air pollution (SO 2 , NO x , CO 2 , CO, CH 4 , N 2 O, NH 3 , Pb, Cd, Hg, dioxin, furans), waste water, waste management and deposit, energy and water consumption. The state of the art in respect of the IPPC-directives (European Integrated Pollution Prevention and Control Bureau) concerning the best available techniques of the different industry sectors is outlined. The application of European laws and regulations in the Austrian industry is described. (a.n.)

  12. Organic lining materials test in flue gas ducts

    International Nuclear Information System (INIS)

    Raveh, R.; Sfez, D.; Johannsson, L.

    1998-01-01

    Corrosion protection solutions are being widely used in electric power plants equipped with Flue Gas Desulfurization (FGD) systems. Organic lining materials are one of many solutions available on the market for corrosion protection. This market segment is found in a continuous development in order to fulfill the severe demands of these materials. The main goal of this test is to obtain information about the high temperature resistance of the materials as occurs when the FGD system is by-passed. Aster initial investigation of this market segment only a few lining materials were found compatible according to their manufacturer data. Seven of these materials were installed in the outlet flue gas duct of the Israeli power station M.D. B. This power station is not equipped with a FGD system, thus it gives a real simulation of the environmental conditions into which the lining material is subjected when the FGD system is by-passed. The materials installation was observed carefully and performed by representatives from the manufacturers in order to avoid material failure due to a non-adequate application. The power station was shut down and the lining materials were inspected three and a half months after the lining materials were applied. The inspection results were good and besides changes in the lining color, most materials did not show any damages. During that time the flue gas temperature at the duct was 134?C except some temperature fluctuations

  13. Treatment Options for Extrahepatic Bile Duct Cancer

    Science.gov (United States)

    ... Treatment Liver Cancer Prevention Liver Cancer Screening Research Bile Duct Cancer (Cholangiocarcinoma) Treatment (PDQ®)–Patient Version Treatment ... are different types of treatment for patients with bile duct cancer. Different types of treatments are available ...

  14. Treatment Option Overview (Extrahepatic Bile Duct Cancer)

    Science.gov (United States)

    ... Treatment Liver Cancer Prevention Liver Cancer Screening Research Bile Duct Cancer (Cholangiocarcinoma) Treatment (PDQ®)–Patient Version Treatment ... are different types of treatment for patients with bile duct cancer. Different types of treatments are available ...

  15. General Information about Extrahepatic Bile Duct Cancer

    Science.gov (United States)

    ... Treatment Liver Cancer Prevention Liver Cancer Screening Research Bile Duct Cancer (Cholangiocarcinoma) Treatment (PDQ®)–Patient Version Treatment ... are different types of treatment for patients with bile duct cancer. Different types of treatments are available ...

  16. 14 CFR 29.1103 - Induction systems ducts and air duct systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Induction systems ducts and air duct systems. 29.1103 Section 29.1103 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Induction System § 29.1103 Induction systems ducts and air duct...

  17. Bio-films and processes of bio-corrosion and bio-deterioration in oil-and gas-processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Kholodenko, V.P.; Irkhina, I.A.; Chugunov, V.A.; Rodin, V.B.; Zhigletsova, S.K.; Yermolenko, Z.M.; Rudavin, V.V. [State Research Center for Applied Microbiology, Obolensk, Moscow region (Russian Federation)

    2004-07-01

    As a rule, oil- and gas-processing equipment and pipelines are attacked by different microorganisms. Their vital ability determines processes of bio-deterioration and bio-corrosion that lead often to technological accidents and severe environmental contamination. Bio-films presenting a complex association of different microorganisms and their metabolites are responsible for most of damages. In this context, to study the role bio-films may play in processes of bio-damages and in efficacy of protective measures is important. We have developed method of culturing bio-films on the surface of metal coupons by using a natural microbial association isolated from oil-processing sites. Simple and informative methods of determining microbiological parameters of bio-films required to study bio-corrosion processes are also developed. In addition, a method of electron microscopic analysis of bio-films and pitting corrosion is offered. Using these methods, we conducted model experiments to determine the dynamics of corrosion processes depending on qualitative and quantitative composition of bio-films, aeration conditions and duration of the experiment. A harmful effect of soil bacteria and micro-mycetes on different pipeline coatings was also investigated. Experiments were conducted within 3-6 months and revealed degrading action of microorganisms. This was confirmed by axial tension testing of coatings. All these approaches will be used for further development of measures to protect gas- and oil-processing equipment and pipelines against bio-corrosion and bio-damages (first of all biocides). (authors)

  18. Effect of Elemental Sulfur and Sulfide on the Corrosion Behavior of Cr-Mo Low Alloy Steel for Tubing and Tubular Components in Oil and Gas Industry.

    Science.gov (United States)

    Khaksar, Ladan; Shirokoff, John

    2017-04-20

    The chemical degradation of alloy components in sulfur-containing environments is a major concern in oil and gas production. This paper discusses the effect of elemental sulfur and its simplest anion, sulfide, on the corrosion of Cr-Mo alloy steel at pH 2 and 5 during 10, 20 and 30 h immersion in two different solutions. 4130 Cr-Mo alloy steel is widely used as tubing and tubular components in sour services. According to the previous research in aqueous conditions, contact of solid sulfur with alloy steel can initiate catastrophic corrosion problems. The corrosion behavior was monitored by the potentiodynamic polarization technique during the experiments. Energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) have been applied to characterize the corrosion product layers after each experiment. The results show that under the same experimental conditions, the corrosion resistance of Cr-Mo alloy in the presence of elemental sulfur is significantly lower than its resistance in the presence of sulfide ions.

  19. Corrosion in airframes

    OpenAIRE

    PETROVIC ZORAN C.

    2016-01-01

    The introductory chapter provides a brief reference to the issue of corrosion and corrosion damage to aircraft structures. Depending on the nature and dimensions of this non uniformity, three different categories of corrosion are defined: uniform, selective and localized corrosion. The following chapters present the forms of corrosion that can occur in three defined categories of corrosion. Conditions that cause certain types of corrosion in various corrosive environments are discussed. Examp...

  20. Thoracic duct lymphography by subcutaneous contrast agent ...

    African Journals Online (AJOL)

    A second lymphography revealed a collateral thoracic duct that was not detected during the first lymphography. The collateral duct was ligated and chylothorax was resolved after the second surgery. The lymphography applied in this study was minimally-invasive and easily provided images of the thoracic duct in a dog with ...

  1. Wind Turbine With Concentric Ducts

    Science.gov (United States)

    Muhonen, A. J.

    1983-01-01

    Wind Turbine device is relatively compact and efficient. Converging inner and outer ducts increase pressure difference across blades of wind turbine. Turbine shaft drives alternator housed inside exit cone. Suitable for installation on such existing structures as water towers, barns, houses, and commercial buildings.

  2. Monitoring of Grouting Compactness in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers

    Directory of Open Access Journals (Sweden)

    Tianyong Jiang

    2016-08-01

    Full Text Available A post-tensioning tendon duct filled with grout can effectively prevent corrosion of the reinforcement, maintain bonding behavior between the reinforcement and concrete, and enhance the load bearing capacity of concrete structures. In practice, grouting of the post-tensioning tendon ducts always causes quality problems, which may reduce structural integrity and service life, and even cause accidents. However, monitoring of the grouting compactness is still a challenge due to the invisibility of the grout in the duct during the grouting process. This paper presents a stress wave-based active sensing approach using piezoceramic transducers to monitor the grouting compactness in real time. A segment of a commercial tendon duct was used as research object in this study. One lead zirconate titanate (PZT piezoceramic transducer with marble protection, called a smart aggregate (SA, was bonded on the tendon and installed in the tendon duct. Two PZT patch sensors were mounted on the top outside surface of the duct, and one PZT patch sensor was bonded on the bottom outside surface of the tendon duct. In the active sensing approach, the SA was used as an actuator to generate a stress wave and the PZT sensors were utilized to detect the wave response. Cement or grout in the duct functions as a wave conduit, which can propagate the stress wave. If the cement or grout is not fully filled in the tendon duct, the top PZT sensors cannot receive much stress wave energy. The experimental procedures simulated four stages during the grout pouring process, which includes empty status, half grouting, 90% grouting, and full grouting of the duct. Experimental results show that the bottom PZT sensor can detect the signal when the grout level increases towards 50%, when a conduit between the SA and PZT sensor is formed. The top PZT sensors cannot receive any signal until the grout process is completely finished. The wavelet packet-based energy analysis was adopted in this

  3. Multimodal method for scattering of sound at a sudden area expansion in a duct with subsonic flow

    NARCIS (Netherlands)

    Kooijman, G.; Testud, P.; Aurégan, Y.; Hirschberg, A.

    2008-01-01

    The scattering of sound at a sudden area expansion in a duct with subsonic mean flow has been modelled with a multimodal method. Technological applications are for instance internal combustion engine exhaust silencers and silencers in industrial duct systems. Both two-dimensional (2D) rectangular

  4. Industrialization

    African Journals Online (AJOL)

    Lucy

    . African states as ... regarded as the most important ingredients that went to add value to land and labour in order for countries ... B. Sutcliffe Industry and Underdevelopment (Massachusetts Addison – Wesley Publishing Company. 1971), pp.

  5. Industrialization

    African Journals Online (AJOL)

    Lucy

    scholar, Walt W. Rostow presented and supported this line of thought in his analysis of ... A Brief Historical Background of Industrialization in Africa ... indicative) The western model allowed for the political economy to be shaped by market.

  6. Corrosion inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, A O

    1965-12-29

    An acid corrosion-inhibiting composition consists essentially of a sugar, and an alkali metal salt selected from the group consisting of iodides and bromides. The weight ratio of the sugar to the alkali metal salt is between 2:1 and about 20,000:1. Also, a corrosion- inhibited phosphoric acid composition comprising at least about 20 wt% of phosphoric acid and between about 0.1 wt% and about 10 wt% of molasses, and between about 0.0005 wt% and about 1 wt% of potassium iodide. The weight ratio of molasses to iodide is greater than about 2:1. (11 claims)

  7. Industry

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Lenny; Roy, Joyashree; Delhotal, K. Casey; Harnisch, Jochen; Matsuhashi, Ryuji; Price, Lynn; Tanaka, Kanako; Worrell, Ernst; Yamba, Francis; Fengqi, Zhou; de la Rue du Can, Stephane; Gielen, Dolf; Joosen, Suzanne; Konar, Manaswita; Matysek, Anna; Miner, Reid; Okazaki, Teruo; Sanders, Johan; Sheinbaum Parado, Claudia

    2007-12-01

    This chapter addresses past, ongoing, and short (to 2010) and medium-term (to 2030) future actions that can be taken to mitigate GHG emissions from the manufacturing and process industries. Globally, and in most countries, CO{sub 2} accounts for more than 90% of CO{sub 2}-eq GHG emissions from the industrial sector (Price et al., 2006; US EPA, 2006b). These CO{sub 2} emissions arise from three sources: (1) the use of fossil fuels for energy, either directly by industry for heat and power generation or indirectly in the generation of purchased electricity and steam; (2) non-energy uses of fossil fuels in chemical processing and metal smelting; and (3) non-fossil fuel sources, for example cement and lime manufacture. Industrial processes also emit other GHGs, e.g.: (1) Nitrous oxide (N{sub 2}O) is emitted as a byproduct of adipic acid, nitric acid and caprolactam production; (2) HFC-23 is emitted as a byproduct of HCFC-22 production, a refrigerant, and also used in fluoroplastics manufacture; (3) Perfluorocarbons (PFCs) are emitted as byproducts of aluminium smelting and in semiconductor manufacture; (4) Sulphur hexafluoride (SF{sub 6}) is emitted in the manufacture, use and, decommissioning of gas insulated electrical switchgear, during the production of flat screen panels and semiconductors, from magnesium die casting and other industrial applications; (5) Methane (CH{sub 4}) is emitted as a byproduct of some chemical processes; and (6) CH{sub 4} and N{sub 2}O can be emitted by food industry waste streams. Many GHG emission mitigation options have been developed for the industrial sector. They fall into three categories: operating procedures, sector-wide technologies and process-specific technologies. A sampling of these options is discussed in Sections 7.2-7.4. The short- and medium-term potential for and cost of all classes of options are discussed in Section 7.5, barriers to the application of these options are addressed in Section 7.6 and the implication of

  8. Corrosion control for low-cost reliability: Preceedings

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This book is Volume 6 of the preceedings from the 12th International Corrosion Congress. The electric power industry workshop dealt with water chemistry control; monitoring of chemical, electrochemical, and biological corrosion; corrosion product analyses; and nuclear and fossil-fuel power plants. All papers have been processed separately for inclusion on the data base

  9. Corrosion inhibitors

    International Nuclear Information System (INIS)

    El Ashry, El Sayed H.; El Nemr, Ahmed; Esawy, Sami A.; Ragab, Safaa

    2006-01-01

    The corrosion inhibition efficiencies of some triazole, oxadiazole and thiadiazole derivatives for steel in presence of acidic medium have been studied by using AM1, PM3, MINDO/3 and MNDO semi-empirical SCF molecular orbital methods. Geometric structures, total negative charge on the molecule (TNC), highest occupied molecular energy level (E HOMO ), lowest unoccupied molecular energy level (E LUMO ), core-core repulsion (CCR), dipole moment (μ) and linear solvation energy terms, molecular volume (V i ) and dipolar-polarization (π *), were correlated to corrosion inhibition efficiency. Four equations were proposed to calculate corrosion inhibition efficiency. The agreement with the experimental data was found to be satisfactory; the standard deviations between the calculated and experimental results ranged between ±0.03 and ±4.18. The inhibition efficiency was closely related to orbital energies (E HOMO and E LUMO ) and μ. The correlation between quantum parameters and experimental inhibition efficiency has been validated by single point calculations for the semi-empirical AM1 structures using B3LYP/6-31G** as a higher level of theory. The proposed equations were applied to predict the corrosion inhibition efficiency of some related structures to select molecules of possible activity from a presumable library of compounds

  10. HAARP-Induced Ionospheric Ducts

    International Nuclear Information System (INIS)

    Milikh, Gennady; Vartanyan, Aram

    2011-01-01

    It is well known that strong electron heating by a powerful HF-facility can lead to the formation of electron and ion density perturbations that stretch along the magnetic field line. Those density perturbations can serve as ducts for ELF waves, both of natural and artificial origin. This paper presents observations of the plasma density perturbations caused by the HF-heating of the ionosphere by the HAARP facility. The low orbit satellite DEMETER was used as a diagnostic tool to measure the electron and ion temperature and density along the satellite orbit overflying close to the magnetic zenith of the HF-heater. Those observations will be then checked against the theoretical model of duct formation due to HF-heating of the ionosphere. The model is based on the modified SAMI2 code, and is validated by comparison with well documented experiments.

  11. Underground pipeline corrosion

    CERN Document Server

    Orazem, Mark

    2014-01-01

    Underground pipelines transporting liquid petroleum products and natural gas are critical components of civil infrastructure, making corrosion prevention an essential part of asset-protection strategy. Underground Pipeline Corrosion provides a basic understanding of the problems associated with corrosion detection and mitigation, and of the state of the art in corrosion prevention. The topics covered in part one include: basic principles for corrosion in underground pipelines, AC-induced corrosion of underground pipelines, significance of corrosion in onshore oil and gas pipelines, n

  12. Passive, wireless corrosion sensors for transportation infrastructure.

    Science.gov (United States)

    2011-07-01

    Many industrial segments including utilities, manufacturing, government and infrastructure have an urgent need for a means to detect corrosion before significant damage occurs. Transportation infrastructure, such as bridges and roads, rely on reinfor...

  13. Available Prediction Methods for Corrosion under Insulation (CUI): A Review

    OpenAIRE

    Burhani Nurul Rawaida Ain; Muhammad Masdi; Ismail Mokhtar Che

    2014-01-01

    Corrosion under insulation (CUI) is an increasingly important issue for the piping in industries especially petrochemical and chemical plants due to its unexpected catastrophic disaster. Therefore, attention towards the maintenance and prediction of CUI occurrence, particularly in the corrosion rates, has grown in recent years. In this study, a literature review in determining the corrosion rates by using various prediction models and method of the corrosion occurrence between the external su...

  14. Data book of anti-corrosion method

    International Nuclear Information System (INIS)

    Lee, Ui Ho

    1997-07-01

    This book deals with cases, influence, cause, standard of corrosion of steel structure, which includes bridges, steel tower, corrosion data, the ocean, ports, and RC structure for civil engineering, exterior materials of construction, building equipment pipes, processing industries such as chemical equipment, oil device, pump and coolant, environment facility like trash incinerator, and sewage process, thermal power generation and nuclear energy generation, and energy industry.

  15. Corrosion and protection of magnesium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ghali, E. [Laval Univ., Quebec City, PQ (Canada). Dept. of Mining and Metallurgy

    2000-07-01

    The oxide film on magnesium offers considerable surface protection in rural and some industrial environments and the corrosion rate lies between that of aluminum and low carbon steels. Galvanic coupling of magnesium alloys, high impurity content such as Ni, Fe, Cu and surface contamination are detrimental for corrosion resistance of magnesium alloys. Alloying elements can form secondary particles which are noble to the Mg matrix, thereby facilitating corrosion, or enrich the corrosion product thereby possibly inhibiting the corrosion rate. Bimetallic corrosion resistance can be increased by fluxless melt protection, choice of compatible alloys, insulating materials, and new high-purity alloys. Magnesium is relatively insensible to oxygen concentration. Pitting, corrosion in the crevices, filiform corrosion are observed. Granular corrosion of magnesium alloys is possible due to the cathodic grain-boundary constituent. More homogeneous microstructures tend to improve corrosion resistance. Under fatigue loading conditions, microcrack initiation in Mg alloys is related to slip in preferentially oriented grains. Coating that exclude the corrosive environments can provide the primary defense against corrosion fatigue. Magnesium alloys that contain neither aluminum nor zinc are the most SCC resistant. Compressive surface residual stresses as that created by short peening increase SCC resistance. Cathodic polarization or cladding with a SCC resistant sheet alloy are good alternatives. Effective corrosion prevention for magnesium alloy components and assemblies should start at the design stage. Selective surface preparation, chemical treatment and coatings are recommended. Oil application, wax coating, anodizing, electroplating, and painting are possible alternatives. Recently, it is found that a magnesium hydride layer, created on the magnesium surface by cathodic charging in aqueous solution is a good base for painting. (orig.)

  16. Quadcopter thrust optimization with ducted-propeller

    Directory of Open Access Journals (Sweden)

    Kuantama Endrowednes

    2017-01-01

    Full Text Available In relation to quadcopter body frame model, propeller can be categorized into propeller with ducted and without ducted. This study present differences between those two using CFD (Computational Fluid Dynamics method. Both categories utilize two blade-propeller with diameter of 406 (mm. Propeller rotation generates acceleration per time unit on the volume of air. Based on the behavior of generated air velocity, ducted propeller can be modeled into three versions. The generated thrust and performance on each model were calculated to determine the best model. The use of ducted propeller increases the total weight of quadcopter and also total thrust. The influence of this modeling were analyzed in detail with variation of angular velocity propeller from 1000 (rpm to 9000 (rpm. Besides the distance between propeller tip and ducted barrier, the size of ducted is also an important part in thrust optimization and total weight minimization of quadcopter.

  17. Aircraft Corrosion

    Science.gov (United States)

    1981-08-01

    attribud au choix de traitements et de rev~tements spproprids. Au contrairo, dens d’sutros structures des corrosions iirportsntea se sont msnifestdes...au traitement . micaniqus qui provoque une compression de surface - h1l’spplication i1’une double protection comportant oxydation snodique et...chlore mais dans une proportion semblable b cells d’une eau de vil)e ; - lea solides, d’aprbs lea analyses chimique et criatallographique, paraissaiont

  18. Synthesis and study of the mechanisms of action of biodegradable additives for corrosion and scale inhibition in industrial cooling water systems; Mise au point et etude des mecanismes d'action d'additifs biodegradables pour l'inhibition du pouvoir entartrant et corrosif des eaux de refroidissement industrielles

    Energy Technology Data Exchange (ETDEWEB)

    Estievenart, C.

    2003-11-01

    Industrial cooling water systems undergo more and more environmental constraints. The recycling of water increases the risks of scale deposition and corrosion. The use of chemical additives to inhibit these phenomena is necessary. Poly-aspartates are proposed as green multi-functional inhibitors. Polymers of different characteristics have been synthesized by different ways. Their efficiency towards scale deposition and corrosion is determined by electrochemical techniques in different test conditions (composition of the test water, temperature, flow rate, concentration of additive...). Their biodegradability is also evaluated. These poly-aspartates inhibit both nucleation and growth of calcium carbonate crystals, but also corrosion. Their efficiency depends on the characteristics of the polymers and their way of synthesis. The morphology of scale and corrosion deposits is modified in the presence of poly-aspartate. The mechanism of action of poly-aspartates combines adsorption, dispersion, complexation with both iron and calcium ions and insertion in the crystal lattice. (author)

  19. Synthesis and study of the mechanisms of action of biodegradable additives for corrosion and scale inhibition in industrial cooling water systems; Mise au point et etude des mecanismes d'action d'additifs biodegradables pour l'inhibition du pouvoir entartrant et corrosif des eaux de refroidissement industrielles

    Energy Technology Data Exchange (ETDEWEB)

    Estievenart, C

    2003-11-01

    Industrial cooling water systems undergo more and more environmental constraints. The recycling of water increases the risks of scale deposition and corrosion. The use of chemical additives to inhibit these phenomena is necessary. Poly-aspartates are proposed as green multi-functional inhibitors. Polymers of different characteristics have been synthesized by different ways. Their efficiency towards scale deposition and corrosion is determined by electrochemical techniques in different test conditions (composition of the test water, temperature, flow rate, concentration of additive...). Their biodegradability is also evaluated. These poly-aspartates inhibit both nucleation and growth of calcium carbonate crystals, but also corrosion. Their efficiency depends on the characteristics of the polymers and their way of synthesis. The morphology of scale and corrosion deposits is modified in the presence of poly-aspartate. The mechanism of action of poly-aspartates combines adsorption, dispersion, complexation with both iron and calcium ions and insertion in the crystal lattice. (author)

  20. Thermal neutrons streaming in straight duct

    International Nuclear Information System (INIS)

    Jehouani, A.; Boulkheir, M.; Ichaoui, R.

    2000-01-01

    The neutron streaming in duct is due to two phenomena: a) direct propagation and b) reflection on duct wall. We have used the Monte Carlo method to evaluate the ratio of the reflected neutrons flux by the duct wall to the total flux at the exit of the duct for iron and aluminium. Ten neutrons energy groups are considered between 10 -5 eV and 10 eV. A Fortran program is developed to evaluate the neutron double differential albedo. It is shown that the two following approximations are largely justified: i) Three collisions in the duct wall are sufficient to attain the asymptotic limit of the multiscattered neutron double differential albedo ii) The points of entry and exit of the neutron in the duct wall may be considered the same for the multiscattered neutrons. For a punctual source at the mouth of the duct, we have determined the direct and the reflected part of the total thermal neutron flux at the exit of the duct for different lengths and different radius of the duct. For a punctual source, we have found that the major contribution to the total flux of neutrons at the exit is due to the neutron reflection by walls and the reflection contribution decreases when the neutron energy decreases. For a constant length of the duct, the reflected part decreases when the duct radius increases while for the disk shaped source we have found the opposite phenomena. The transmitted neutron flux distribution at the exit of the duct are determined for disk shaped source for different neutron energy and for different distance from the exit center. (author)

  1. Molecular Mechanisms of Bile Duct Development

    OpenAIRE

    Zong, Yiwei; Stanger, Ben Z.

    2010-01-01

    The mammalian biliary system, consisting of the intrahepatic and extrahepatic bile ducts, is responsible for transporting bile from the liver to the intestine. Bile duct dysfunction, as is seen in some congenital biliary diseases such as Alagille syndrome and biliary atresia, can lead to the accumulation of bile in the liver, preventing the excretion of detoxification products and ultimately leading to liver damage. Bile duct formation requires coordinated cell-cell interactions, resulting in...

  2. Persistent Mullerian Duct Syndrome with Transverse Testicular ...

    African Journals Online (AJOL)

    Eastham JA, McEvoy K, Sullivan R, Chandrasoma P. A case of simultaneous bilateral nonseminomatous testicular tumors in persistent müllerian duct syndrome. J Urol 1992;148:407-8. 8. Shinmura Y, Yokoi T, Tsutsui Y. A case of clear cell adenocarcinoma of the müllerian duct in persistent müllerian duct syndrome: The first ...

  3. Parotid salivary duct stenosis following caudal maxillectomy.

    Science.gov (United States)

    Mestrinho, Lisa A; Faísca, Pedro B; Niza, Maria M R E

    2014-01-01

    Parotid salivary duct dilation was diagnosed in a 9-year-old male dog. The dog had undergone caudal maxillectomy on the ipsilateral side 2-years prior to presentation. Treatment consisted of parotid salivary duct excision and superficial parotidectomy that lead to the resolution of clinical signs. Transient facial neuropraxia was observed immediately after surgery and resolved spontaneously after 2-weeks. Parotid salivary duct dilation should be considered as a chronic postoperative complication following caudal maxillectomy.

  4. CORROSION RATE OF STEELS DX51D AND S220GD IN DIFFERENT CORROSION ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Alina Crina CIUBOTARIU

    2016-06-01

    Full Text Available Corrosion in the marine environment is an important issue because the costs causes by marine corrosion increased year upon year. It is necessary a correctly approach to materials selection, protection and corrosion control to reduce this burden of wasted materials, wasted energy and wasted money. Many different types of corrosion attack can be observed to structures, ships and other equipment used in sea water service. Shipping containers are exposed to various corrosive mediums like as airborne salt, industrial pollutants, rain and saltwater. Transport damage during loading onto and unloading off trucks, train beds and ships breaches the paint coating which further contributes to corrosion. The result is shortened container life and high costs for container repair or replacement. The paper intends to evaluate, by gravimetric method, the corrosion rate and corrosion penetration rate of two types of carbon steel DX51D and S220GD. Carbon steel DX51D and hot-dip galvanized steel S220GD are used in marine and industrial applications for buildings cargo vessels, container ships and oil tankers. For testing it was used different corrosive environments: 5% NaOH solution; 5% HCL solution and 0.5M NaCl solution. The samples were immersed in 400mL of testing solution for exposure period of 28 days. Periodically at 3 days, 7 days, 14 days, 21 days and 28 days was measured de mass loss and evaluate the corrosion rate and corrosion stability coefficient. The steel DX51D was stable in 5% NaOH solution for 28 days, the values of corrosion stability coefficient was 7 after 3 days and 6 after 28 days of immersion in corrosive medium. In 5% HCL solution steels DX51D and S220GD was completely corroded in 21 days with a corrosion stability coefficient equal with 9 for 7 days and 8 for 21 days of immersion in corrosive solution. It was observed a good resistance for 3 days in 0.5M NaCl solution with a corrosion stability coefficient equal with 5, but after that

  5. Nasopalatine duct cyst: A case report

    Directory of Open Access Journals (Sweden)

    Saikrishna Pasupuleti

    2015-01-01

    Full Text Available Nasopalatine duct cyst (NPDC is the most common non-odontogenic cyst of oral cavity. Clinically, Nasopalatine duct cyst manifests as an asymptomatic swelling of the palate or the upper lip. Radiographically, it is seen as a heart-shaped radiolucency and can be confused with periapical pathology. The aim of this article is to report a case of a nasopalatine duct cyst in a 36-year-old patient which was misinterpreted for a periapical cyst. Diagnosis of a Nasopalatine duct cyst can be given through clinical, radiographical, and histopathological examination.

  6. Algorithm of dynamic regulation of a system of duct, for a high accuracy climatic system

    Science.gov (United States)

    Arbatskiy, A. A.; Afonina, G. N.; Glazov, V. S.

    2017-11-01

    Currently, major part of climatic system, are stationary in projected mode only. At the same time, many modern industrial sites, require constant or periodical changes in technological process. That is 80% of the time, the industrial site is not require ventilation system in projected mode and high precision of climatic parameters must maintain. While that not constantly is in use for climatic systems, which use in parallel for different rooms, we will be have a problem for balance of duct system. For this problem, was created the algorithm for quantity regulation, with minimal changes. Dynamic duct system: Developed of parallel control system of air balance, with high precision of climatic parameters. The Algorithm provide a permanent pressure in main duct, in different a flow of air. Therefore, the ending devises air flow have only one parameter for regulation - flaps open area. Precision of regulation increase and the climatic system provide high precision for temperature and humidity (0,5C for temperature, 5% for relative humidity). Result: The research has been made in CFD-system - PHOENICS. Results for velocity of air in duct, for pressure of air in duct for different operation mode, has been obtained. Equation for air valves positions, with different parameters for climate in room’s, has been obtained. Energy saving potential for dynamic duct system, for different types of a rooms, has been calculated.

  7. Corrosion Testing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Corrosion Testing Facility is part of the Army Corrosion Office (ACO). It is a fully functional atmospheric exposure site, called the Corrosion Instrumented Test...

  8. Materials corrosion and protection at high temperatures

    International Nuclear Information System (INIS)

    Balbaud, F.; Desgranges, Clara; Martinelli, Laure; Rouillard, Fabien; Duhamel, Cecile; Marchetti, Loic; Perrin, Stephane; Molins, Regine; Chevalier, S.; Heintz, O.; David, N.; Fiorani, J.M.; Vilasi, M.; Wouters, Y.; Galerie, A.; Mangelinck, D.; Viguier, B.; Monceau, D.; Soustelle, M.; Pijolat, M.; Favergeon, J.; Brancherie, D.; Moulin, G.; Dawi, K.; Wolski, K.; Barnier, V.; Rebillat, F.; Lavigne, O.; Brossard, J.M.; Ropital, F.; Mougin, J.

    2011-01-01

    This book was made from the lectures given in 2010 at the thematic school on 'materials corrosion and protection at high temperatures'. It gathers the contributions from scientists and engineers coming from various communities and presents a state-of-the-art of the scientific and technological developments concerning the behaviour of materials at high temperature, in aggressive environments and in various domains (aerospace, nuclear, energy valorization, and chemical industries). It supplies pedagogical tools to grasp high temperature corrosion thanks to the understanding of oxidation mechanisms. It proposes some protection solutions for materials and structures. Content: 1 - corrosion costs; macro-economical and metallurgical approach; 2 - basic concepts of thermo-chemistry; 3 - introduction to the Calphad (calculation of phase diagrams) method; 4 - use of the thermodynamic tool: application to pack-cementation; 5 - elements of crystallography and of real solids description; 6 - diffusion in solids; 7 - notions of mechanics inside crystals; 8 - high temperature corrosion: phenomena, models, simulations; 9 - pseudo-stationary regime in heterogeneous kinetics; 10 - nucleation, growth and kinetic models; 11 - test experiments in heterogeneous kinetics; 12 - mechanical aspects of metal/oxide systems; 13 - coupling phenomena in high temperature oxidation; 14 - other corrosion types; 15 - methods of oxidized surfaces analysis at micro- and nano-scales; 16 - use of SIMS in the study of high temperature corrosion of metals and alloys; 17 - oxidation of ceramics and of ceramic matrix composite materials; 18 - protective coatings against corrosion and oxidation; 19 - high temperature corrosion in the 4. generation of nuclear reactor systems; 20 - heat exchangers corrosion in municipal waste energy valorization facilities; 21 - high temperature corrosion in oil refining and petrochemistry; 22 - high temperature corrosion in new energies industry. (J.S.)

  9. Corrosion technology. V. 1

    International Nuclear Information System (INIS)

    Khan, I.H.

    1989-01-01

    This book has been produced for dissemination of information on corrosion technology, corrosion hazards and its control. Chapter one of this book presents an overall view of the subject and chapter 2-5 deals with electrochemical basics, types of corrosion, pourbaix diagrams and form of corrosion. The author explains polarization/kinetics of corrosion, passivity, aqueous corrosion and corrosion testing and monitoring in 6-11 chapters. The author hopes it will provide incentive to all those interested in the corrosion technology. (A.B.)

  10. New corrosion issues in gas sweetening plants

    Energy Technology Data Exchange (ETDEWEB)

    Asperger, R.G. (CLI International and Asperger Technologies, Houston, TX (United States))

    Gas treating plants are experiencing corrosion problems which impact on efficiency and safety. While general corrosion is not particularly hazardous in the gas processing industry, local corrosion is very dangerous since it has several different mechanisms, all of which have dangerously high rates, and it occurs at locations which are hard to find and hard to predict. A newly discovered, velocity-dependent type of corrosion is reported. It is related to yet-undefined species which cause excessively high corrosion in areas of turbulence. This accelerated corrosion is not due to erosion or cavitation, but to a diffusion-limited reaction accelerated by turbulence. A full-flow test loop was built to evaluate the corrosiveness of gas plant solutions at their normal temperature and flow rates. Test runs were conducted with Co[sub 2]-loaded amine solutions for periods of 12 days. Carbon steel specimens mounted in the test loop were examined and corrosion rates calculated. Chromium alloys were shown to be attacked by corrodents in the low-velocity part of the loop and very aggressively attacked in the high-velocity part. The tests demonstrate the need for rigorous monitoring of corrosion in areas of higher velocity such as piping elbows and other points of turbulence. 5 refs., 2 figs., 3 tabs.

  11. Measure Guideline: Sealing and Insulating of Ducts in Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, R.; Puttagunta, S.

    2011-12-01

    This document begins with a discussion on potential cost and performance benefits of duct sealing and insulating. It continues with a review of typical duct materials and components and the overall procedures for assessing and improving the duct system.

  12. Measure Guideline. Sealing and Insulating Ducts in Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, R. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Puttagunta, S. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2011-12-01

    This document begins with a discussion on potential cost and performance benefits of duct sealing and insulating. It continues with a review of typical duct materials and components and the overall procedures for assessing and improving the duct system.

  13. A new insight into resource recovery of excess sewage sludge: Feasibility of extracting mixed amino acids as an environment-friendly corrosion inhibitor for industrial pickling

    Energy Technology Data Exchange (ETDEWEB)

    Su, Wen; Tang, Bing, E-mail: renytang@163.com; Fu, Fenglian; Huang, Shaosong; Zhao, Shiyuan; Bin, Liying; Ding, Jiewei; Chen, Cuiqun

    2014-08-30

    Graphical abstract: - Highlights: • A value-added product was extracted from the municipal excess sludge. • The effective components contained in the product were mixed amino acids. • The product could provide a reliable protection to the steel from the acid medium. • A new insight into the resource recovery of excess sewage sludge was provided. - Abstract: The work mainly presented a laboratory-scale investigation on an effective process to extract a value-added product from municipal excess sludge. The functional groups in the hydrolysate were characterized with Fourier transform infrared spectrum, and the contained amino acids were measured by means of an automatic amino acid analyzer. The corrosion-inhibition characteristics of the hydrolysate were determined with weight-loss measurement, electrochemical polarization and scanning electron microscopy. Results indicated that the hydrolysate contained 15 kinds of amino acid, and their adsorption on the surface could effectively inhibit the corrosion reaction of the steel from the acid medium. Polarization curves indicated that the obtained hydrolysate was a mixed-type inhibitor, but mainly restricted metal dissolution on the anode. The adsorption accorded well with the Langmuir adsorption isotherm, involved an increase in entropy, and was a spontaneous, exothermic process.

  14. A new insight into resource recovery of excess sewage sludge: Feasibility of extracting mixed amino acids as an environment-friendly corrosion inhibitor for industrial pickling

    International Nuclear Information System (INIS)

    Su, Wen; Tang, Bing; Fu, Fenglian; Huang, Shaosong; Zhao, Shiyuan; Bin, Liying; Ding, Jiewei; Chen, Cuiqun

    2014-01-01

    Graphical abstract: - Highlights: • A value-added product was extracted from the municipal excess sludge. • The effective components contained in the product were mixed amino acids. • The product could provide a reliable protection to the steel from the acid medium. • A new insight into the resource recovery of excess sewage sludge was provided. - Abstract: The work mainly presented a laboratory-scale investigation on an effective process to extract a value-added product from municipal excess sludge. The functional groups in the hydrolysate were characterized with Fourier transform infrared spectrum, and the contained amino acids were measured by means of an automatic amino acid analyzer. The corrosion-inhibition characteristics of the hydrolysate were determined with weight-loss measurement, electrochemical polarization and scanning electron microscopy. Results indicated that the hydrolysate contained 15 kinds of amino acid, and their adsorption on the surface could effectively inhibit the corrosion reaction of the steel from the acid medium. Polarization curves indicated that the obtained hydrolysate was a mixed-type inhibitor, but mainly restricted metal dissolution on the anode. The adsorption accorded well with the Langmuir adsorption isotherm, involved an increase in entropy, and was a spontaneous, exothermic process

  15. Corrosion monitoring using FSM technology

    International Nuclear Information System (INIS)

    Strommen, R.; Horn, H.; Gartland, P.O.; Wold, K.; Haroun, M.

    1995-01-01

    FSM is a non-intrusive monitoring technique based on a patented principle, developed for the purpose of detection and monitoring of both general and localized corrosion, erosion, and cracking in steel and metal structures, piping systems, and vessels. Since 1991, FSM has been used for a wide range of applications, including for buried and open pipelines, process piping offshore, subsea pipelines and flowlines, applications in the nuclear power industry, and in materials, research in general. This paper describes typical applications of the FSM technology, and presents operational experience from some of the land-based and subsea installations. The paper also describes recent enhancements in the FSM technology and in the analysis of FSM readings, allowing for monitoring and detailed quantification of pitting and mesa corrosion, and of corrosion in welds

  16. Characterization of Corrosion Products on Carbon Steel Exposed to Natural Weathering and to Accelerated Corrosion Tests

    Directory of Open Access Journals (Sweden)

    Renato Altobelli Antunes

    2014-01-01

    Full Text Available The aim of this work was to compare the corrosion products formed on carbon steel plates submitted to atmospheric corrosion in urban and industrial atmospheres with those formed after accelerated corrosion tests. The corrosion products were characterized by X-ray diffraction, Mössbauer spectroscopy, and Raman spectroscopy. The specimens were exposed to natural weathering in both atmospheres for nine months. The morphologies of the corrosion products were evaluated using scanning electron microscopy. The main product found was lepidocrocite. Goethite and magnetite were also found on the corroded specimens but in lower concentrations. The results showed that the accelerated test based on the ASTM B117 procedure presented poor correlation with the atmospheric corrosion tests whereas an alternated fog/dry cycle combined with UV radiation exposure provided better correlation.

  17. Ducted wind turbine optimization : A numerical approach

    NARCIS (Netherlands)

    Dighe, V.V.; De Oliveira Andrade, G.L.; van Bussel, G.J.W.

    2017-01-01

    The practice of ducting wind turbines has shown a beneficial effect on the overall performance, when compared to an open turbine of the same rotor diameter1. However, an optimization study specifically for ducted wind turbines (DWT’s) is missing or incomplete. This work focuses on a numerical

  18. Visualization of the thoracic duct by lymphoscintigraphy

    International Nuclear Information System (INIS)

    Baulieu, F.; Baulieu, J.L.; Itti, R.; Tours Univ., 37

    1987-01-01

    Imaging of the thoracic duct is usually performed by radiological lymphography. However, this procedure, which uses an oil based dye injected directly into the lymph channels, has some adverse effects. In this paper we note that lymphoscintigraphy, a physiological and non invasive method, may visualize thoracic duct abnormalities, and might be particularly usefull when radiological lymphography is contraindicated. (orig.)

  19. Vacuum exhaust duct used for thermonuclear device

    International Nuclear Information System (INIS)

    Tachikawa, Nobuo; Kondo, Mitsuaki; Honda, Tsutomu.

    1990-01-01

    The present invention concerns a vacuum exhaust duct used for a thermonuclear device. A cylindrical metal liners is lined with a gap to the inside of a vacuum exhaust duct main body. Bellows are connected to both ends of the metal liners and the end of the bellows is welded to the vacuum exhaust duct main body. Futher, a heater is mounted to the metal liner on the side of the vacuum exhaust duct main body, and the metal liner is heated by the heater to conduct baking for the vacuum exhaust duct main body. Accordingly, since there is no requirement for elevating the temperature of the vacuum exhaust duct upon conducting baking, the vacuum exhaust duct scarcely suffers substantial deformation due to heat expansion. Further, there is also no substantial deformation for the bellows disposed between the outer circumference of the vacuum vessel and a portion of a vacuum exhaust duct, so that the durability of the bellows is greatly improved. (I.S.)

  20. Ultrasonic Guided Wave Technology for Non-Invasive Assessment of Corrosion-Induced Damage in Piping for Pollution Prevention in DOD Fuel Storage Facilities

    Science.gov (United States)

    2011-08-01

    using a mixture of rock salt and tap water. A combination of lacquer and duct tape was used to mask the desired corrosion areas and to prevent excessive...Corrosion Measurements," NDT efT E International, Vol. 37, No.3, 2004, pp. 167-180. Demma, A, P. Cawley, M. Lowe and B. Pavlakovic, "The Effect of

  1. Cholangiographic evaluation of bile duct carcinoma

    International Nuclear Information System (INIS)

    Nichols, D.A.; MacCarty, R.L.; Gaffey, T.A.

    1983-01-01

    Cholangiograms and clinical histories of 82 patients with biopsy-proved bile duct carcinoma were reviewed. The carcinomas were classified according to morphologic findings and clinical outcome. Ulcerative colitis and antecedent inflammatory disease of the biliary tree, particularly primary sclerosing cholangitis, seem to predispose to the development of bile duct carcinoma. Focal stenotic lesions were the most common morphologic type (62/82). Polypoid carcinomas and diffuse sclerosing carcinomas were less common and of about equal frequency. Prognosis was best for patients with polypoid carcinomas and worst for those with diffuse sclerosing carcinomas. In 69 cases (84%), the tumors involved the intrahepatic or proximal extrahepatic ducts, makin curative resection difficult or impossible. Patients with carcinomas limited to the more distal extrahepatic bile ducts had a longer average survival and a higher probability of surgical cure. Proper management of patients with bile duct carcinoma requires a complete and accurate cholangiographic evaluation of the morphology, location, and extent of the disease

  2. Passive Corrosion Behavior of Alloy 22

    International Nuclear Information System (INIS)

    R.B. Rebak; J.H. Payer

    2006-01-01

    Alloy 22 (NO6022) was designed to stand the most aggressive industrial applications, including both reducing and oxidizing acids. Even in the most aggressive environments, if the temperature is lower than 150 F (66 C) Alloy 22 would remain in the passive state having particularly low corrosion rates. In multi-ionic solutions that may simulate the behavior of concentrated ground water, even at near boiling temperatures, the corrosion rate of Alloy 22 is only a few nano-meters per year because the alloy is in the complete passive state. The corrosion rate of passive Alloy 22 decreases as the time increases. Immersion corrosion testing also show that the newer generation of Ni-Cr-Mo alloys may offer a better corrosion resistance than Alloy 22 only in some highly aggressive conditions such as in hot acids

  3. A new corrosion monitoring technique

    International Nuclear Information System (INIS)

    Brown, Gerald K.

    2000-01-01

    Internal Corrosion Monitoring has relied upon 5 basic techniques. Little improvement in performance has been achieved in any of these. Many newer internal corrosion monitoring techniques have proved of little value in the field although some have instances of success in the laboratory. Industry has many high value hydrocarbon applications requiring corrosion rate monitoring for real-time problem solving and control. The high value of assets and the cost of asset replacement makes it necessary to practice cost effective process and corrosion control with sensitivity beyond the 5 basic techniques. This new metal loss technology offers this sensitivity. Traditional metal loss technology today provides either high sensitivity with short life, or conversely, long life but with substantially reduced sensitivity. The new metal loss technology offers an improved working life of sensors without significantly compromising performance. The paper discusses the limitations of existing on-line technologies and describes the performance of a new technology. This new metal loss technology was introduced at NACE Corrosion 99'. Since that time several field projects have been completed or are ongoing. This paper will discuss the new metal loss technology and report on some of the data that has been obtained.(author)

  4. Thermal performance test of hot gas ducts of helium engineering demonstration loop (HENDEL)

    International Nuclear Information System (INIS)

    Hishida, Makoto; Kunitomi, Kazuhiko; Ioka, Ikuo; Umenishi, Koji; Kondo, Yasuo; Tanaka, Toshiyuki; Shimomura, Hiroaki

    1984-01-01

    A hot gas duct provided with internal thermal insulation is supposed to be used for an experimental very high-temperature gas-cooled reactor (VHTR) which has been developed by the Japan Atomic Energy Research Institute (JAERI). This type of hot gas duct has not been used so far in industrial facilities, and only a couple of tests on such a large-scale model of hot gas duct have been conducted. The present test was to investigate the thermal performance of the hot gas ducts which are installed as parts of a helium engineering demonstration loop (HENDEL) of JAERI. Uniform temperature and heat flux distributions at the surface of the duct were observed, the experimental correlation being obtained for the effective thermal conductivity of the internal thermal insulation layer. The measured temperature distribution of the pressure tube was in good agreement with the calculation by a TRUMP heat transfer computer code. The temperature distribution of the inner tube of VHTR hot gas duct was evaluated, and no hot spot was detected. These results would be very valuable for the design and development of VHTR. (author)

  5. Corrosion behavior of corrosion resistant alloys in stimulation acids

    Energy Technology Data Exchange (ETDEWEB)

    Cheldi, Tiziana [ENI E and P Division, 20097 San Donato Milanese Milano (Italy); Piccolo, Eugenio Lo; Scoppio, Lucrezia [Centro Sviluppo Materiali, via Castel Romano 100, 00128 Rome (Italy)

    2004-07-01

    In the oil and gas industry, selection of CRAs for downhole tubulars is generally based on resistance to corrosive species in the production environment containing CO{sub 2}, H{sub 2}S, chloride and in some case elemental sulphur. However, there are non-production environments to which these materials must also be resistant for either short term or prolonged duration; these environments include stimulation acids, brine and completion fluids. This paper reports the main results of a laboratory study performed to evaluate the corrosion and stress corrosion behaviour to the acidizing treatments of the most used CRAs for production tubing and casing. Laboratory tests were performed to simulate both 'active' and 'spent' acids operative phases, selecting various environmental conditions. The selected steel pipes were a low alloyed steel, martensitic, super-martensitic, duplex 22 Cr, superduplex 25 Cr and super-austenitic stainless steels (25 Cr 35 Ni). Results obtained in the 'active' acid environments over the temperature range of 100-140 deg. C, showed that the blend acids with HCl at high concentration and HCl + HF represented too much severe conditions, where preventing high general corrosion and heavy localised corrosion by inhibition package becomes very difficult, especially for duplex steel pipe, where, in some case, the specimens were completely dissolved into the solution. On the contrary, all steels pipes were successfully protected by inhibitor when organic acid solution (HCOOH + CH{sub 3}COOH) were used. Furthermore, different effectiveness on corrosion protection was showed by the tested inhibitors packages: e.g. in the 90% HCl at 12% + 10 CH{sub 3}COOH acid blend. In 'spent' acid environments, all steel pipes showed to be less susceptible to the localised and general corrosion attack. Moreover, no Sulphide Stress Corrosion Cracking (SSC) was observed. Only one super-austenitic stainless steel U-bend specimen showed

  6. Accelerated Corrosion Testing

    Science.gov (United States)

    1982-12-01

    Treaty Organization, Brussels, 1971), p. 449. 14. D. 0. Sprowls, T. J. Summerson, G. M. Ugianski, S. G. Epstein, and H. L. Craig , Jr., in Stress...National Association of Corrosion Engineers Houston, TX, 1972). 22. H. L. Craig , Jr. (ed.), Stress Corrosion-New Approaches, ASTM-STP- 610 (American...62. M. Hishida and H. Nakada, Corrosion 33 (11) 403 (1977). b3. D. C. Deegan and B. E. Wilde, Corrosion 34 (6), 19 (1978). 64. S. Orman, Corrosion Sci

  7. Bile Duct Adenoma with Oncocytic Features

    Directory of Open Access Journals (Sweden)

    E. J. Johannesen

    2014-01-01

    Full Text Available Bile duct adenomas are benign bile duct proliferations usually encountered as an incidental finding. Oncocytic bile duct neoplasms are rare and the majority are malignant. A 61-year-old male with a diagnosis of colorectal adenocarcinoma was undergoing surgery when a small white nodule was discovered on the surface of the right lobe of his liver. This lesion was composed of cytologically bland cells arranged in tightly packed glands. These cells were immunopositive for cytokeratin 7, negative for Hep Par 1, contained mucin, and had a Ki67 proliferation index of 8%. The morphology, immunophenotype, presence of mucin, and normal appearing bile ducts, as well as the increased Ki67 proliferation rate, were consistent with a bile duct adenoma with oxyphilic (oncocytic change. Oncocytic tumors in the liver are rare; the first described in 1992. Only two bile duct adenomas with oncocytic change have been reported and neither of them had reported mucin production or the presence of normal appearing bile ducts within the lesion.

  8. Financial Aspects of Bile Duct Injuries.

    Science.gov (United States)

    Palaz Alı, Ozgkıour; Ibis, Abdil Cem; Gurtekin, Basak

    2017-11-04

    BACKGROUND Major bile duct injury is the most worrisome complication of cholecystectomy. There is no detailed data about the incidence or treatment-related costs of bile duct injuries in Turkey. We aimed to determine prevalence and therapeutic costs of patients with major biliary duct injuries managed in our department, and further estimate a projection of these parameters at the national level. MATERIAL AND METHODS All patients admitted due to bile duct injury during cholecystectomy from 2011 to 2014 were included. Healthcare costs were calculated by summing of their all treatment-related costs in Istanbul Medical Faculty. We collected 2014-2015 data on number of patients diagnosed with cholecystitis in Turkey, the number of cholecystectomies, and the number of the interventions performed following these initial surgeries, which were obtained from the Turkish Social Security Institution. RESULTS Forty-nine patients were enrolled and bilioenteric diversion was performed in 39 patients: 20.4% of patients had Bismuth II, 38.8% had Bismuth III, and 40.8% had Bismuth IV biliary stricture. Comparison of stricture types with total costs, days of hospitalization, and outpatient clinic costs revealed significant differences. Mean total cost of corrective surgeries was 9199 TRY. We estimated that 1.5% to 2.4% of patients who underwent cholecystectomy in Turkey have bile duct injury (including 0.3% with major bile duct injury). CONCLUSIONS New preventive strategies should be used to avoid bile duct injuries, which have a huge financial impact on the national economy.

  9. Corrosion control in electric power plants

    International Nuclear Information System (INIS)

    Syrett, B.C.

    1992-01-01

    This paper reports that corrosion of components in power plants costs the US electric power utility industry billions of dollars each year. Through the Electric Power Research Institute's (EPRI) research and development, several approaches have been developed to reduce these huge costs. They include improved materials selection procedures, coatings, cathodic protection, inhibitors, removal of aggressive species from the environment, and on-line corrosion monitoring. In addition, as part of an on-going technology transfer effort, EPRI is developing databases and expert systems that will help utilities obtain corrosion information and guide them in materials selection and failure analysis

  10. [Salivary gland drainage into the thyroglossal duct].

    Science.gov (United States)

    Siem, G; Natvig, K; Kolbenstvedt, A; Lømo, J

    2001-01-20

    Failure in regression of the thyroglossal duct is one of the most common reasons for midline swellings in the neck. Several authors have described recurrent thyroglossal duct remnants with persisting draining sinuses. However, few have described accessory salivary glands that drain into the thyroglossal duct. In this article we report two such cases with midline salivary glands in the floor of the mouth. These two patients were subsequently successfully treated with radical tissue resection in the area between the hyoid bone and foramen cecum. Preoperative fistulography or sinography was useful to demonstrate the ductal ramification of the salivary glands, and use of methylene blue during surgery proved of significant value for the result.

  11. Building America Case Study: Compact Buried Ducts in a Hot-Humid Climate House, Lady's Island, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    2016-02-01

    A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely on encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences, 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs, and 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.

  12. Development of Copper Corrosion Products and Relation between Surface Appearance and Corrosion Rate

    International Nuclear Information System (INIS)

    Lan, Tran Thi Ngoc; Binh, Nguyen Thi Thanh; Tru, Nguyen Nhi; Yoshino, Tsujino; Yasuki, Maeda

    2008-01-01

    Copper was exposed unsheltered and sheltered in four humid tropical sites, representing urban, urban-industrial, urban-marine and rural environments. The corrosion rates and the sequence of corrosion product formation are presented and discussed in relation with climatic and atmospheric pollution parameters. Chemical compositions of corrosion products were found to depend on environments and duration of exposure. In all environments, cuprite was the predominating corrosion product that formed first and continuously increased during the exposure. Among the sulphur-containing corrosion products, posnjakite and brochantite were more frequently found and the first formed earlier. Nantokite was the most common chlorine-containing products for most cases, except the high-chloride environment, where atacamite was detected instead. The corrosion rate of copper was well indicated by the colour of patina. The red-purple colour corresponded to the high corrosion rate and the greenish grey colour corresponded to the low corrosion rate. Corrosion rate of sheltered copper in urban-marine environment increased with the exposure time

  13. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    2000-01-01

    corrosion rates, when biofilm and corrosion products cover the steel surface. However, EIS might be used for detection of MIC. EN is a suitable technique to characterise the type of corrosion attack, but is unsuitable for corrosion rate estimation. The concentric electrodes galvanic probe arrangement......Abstract Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria, e.g. on pipelines buried in soil and on marine structures. MIC...... of carbon steel must be monitored on-line in order to provide an efficient protection and control the corrosion. A number of monitoring techniques is industrially used today, and the applicability and reliability of these for monitoring MIC is evaluated. Coupons and ER are recommended as necessary basic...

  14. Reference values of MRI measurements of the common bile duct and pancreatic duct in children

    Energy Technology Data Exchange (ETDEWEB)

    Gwal, Kriti; Bedoya, Maria A.; Patel, Neal; Darge, Kassa; Anupindi, Sudha A. [University of Pennsylvania Perelman School of Medicine, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Rambhatla, Siri J. [Beth Israel Medical Center, Department of Pediatrics, Newark, NJ (United States); Sreedharan, Ram R. [University of Pennsylvania, Departments of Gastroenterology, Hepatology and Nutrition, The Children' s Hospital of Philadelphia, Perelman School of Medicine, Philadelphia, PA (United States)

    2015-08-15

    Magnetic resonance imaging/cholangiopancreatography (MRI/MRCP) is now an essential imaging modality for the evaluation of biliary and pancreatic pathology in children, but there are no data depicting the normal diameters of the common bile duct (CBD) and pancreatic duct. Recognition of abnormal duct size is important and the increasing use of MRCP necessitates normal MRI measurements. To present normal MRI measurements for the common bile duct and pancreatic duct in children. In this retrospective study we searched all children ages birth to 10 years in our MR urography (MRU) database from 2006 until 2013. We excluded children with a history of hepatobiliary or pancreatic surgery. We stratified 204 children into five age groups and retrospectively measured the CBD and the pancreatic duct on 2-D axial and 3-D coronal T2-weighted sequences. We performed statistical analysis, using logistic and linear regressions to detect the age association of the visibility and size of the duct measurements. We used non-parametric tests to detect gender and imaging plane differences. Our study included 204 children, 106 (52%) boys and 98 (48%) girls, with a median age of 33 months (range 0-119 months). The children were distributed into five age groups. The common bile duct was visible in all children in all age groups. The pancreatic duct was significantly less visible in the youngest children, group 1 (54/67, 80.5%; P = 0.003) than in the oldest children, group 5 (22/22, 100%). In group 2 the pancreatic duct was seen in 19/21 (90.4%), in group 3 52/55 (94.5%), and in group 4 39/39 (100%). All duct measurements increased with age (P < 0.001; r-value > 0.423), and the incremental differences between ages were significant. The measurement variations between the axial and coronal planes were statistically significant (P < 0.001); however these differences were fractions of millimeters. For example, in group 1 the mean coronal measurement of the CBD was 2.1 mm and the axial

  15. Reference values of MRI measurements of the common bile duct and pancreatic duct in children

    International Nuclear Information System (INIS)

    Gwal, Kriti; Bedoya, Maria A.; Patel, Neal; Darge, Kassa; Anupindi, Sudha A.; Rambhatla, Siri J.; Sreedharan, Ram R.

    2015-01-01

    Magnetic resonance imaging/cholangiopancreatography (MRI/MRCP) is now an essential imaging modality for the evaluation of biliary and pancreatic pathology in children, but there are no data depicting the normal diameters of the common bile duct (CBD) and pancreatic duct. Recognition of abnormal duct size is important and the increasing use of MRCP necessitates normal MRI measurements. To present normal MRI measurements for the common bile duct and pancreatic duct in children. In this retrospective study we searched all children ages birth to 10 years in our MR urography (MRU) database from 2006 until 2013. We excluded children with a history of hepatobiliary or pancreatic surgery. We stratified 204 children into five age groups and retrospectively measured the CBD and the pancreatic duct on 2-D axial and 3-D coronal T2-weighted sequences. We performed statistical analysis, using logistic and linear regressions to detect the age association of the visibility and size of the duct measurements. We used non-parametric tests to detect gender and imaging plane differences. Our study included 204 children, 106 (52%) boys and 98 (48%) girls, with a median age of 33 months (range 0-119 months). The children were distributed into five age groups. The common bile duct was visible in all children in all age groups. The pancreatic duct was significantly less visible in the youngest children, group 1 (54/67, 80.5%; P = 0.003) than in the oldest children, group 5 (22/22, 100%). In group 2 the pancreatic duct was seen in 19/21 (90.4%), in group 3 52/55 (94.5%), and in group 4 39/39 (100%). All duct measurements increased with age (P < 0.001; r-value > 0.423), and the incremental differences between ages were significant. The measurement variations between the axial and coronal planes were statistically significant (P < 0.001); however these differences were fractions of millimeters. For example, in group 1 the mean coronal measurement of the CBD was 2.1 mm and the axial

  16. Transmission of wave energy in curved ducts

    Science.gov (United States)

    Rostafinski, W.

    1973-01-01

    A formation of wave energy flow was developed for motion in curved ducts. A parametric study over a range of frequencies determined the ability of circular bends to transmit energy for the case of perfectly rigid walls.

  17. Submandibular duct sialolithiasis an unusual presentation

    International Nuclear Information System (INIS)

    Shafi, M.; Jafferi, S.; Jafferi, S.

    2006-01-01

    Multiple calculi in a submandibular gland duct is an uncommon occurrence. One such case occurring in a young boy of 25 years is reported here where thirteen very small stones of 1-3 mm of maximum diameter were lined up in the Wharton's duct in such a way that they were difficult to appreciate on inspection and palpation. Successful exploration was done in two steps. (author)

  18. Hollow-duct radiation delivery system investigation

    Directory of Open Access Journals (Sweden)

    Kramer D.

    2013-05-01

    Full Text Available Investigation of hollow-duct structure for high-power laser-diode-array radiation delivery into the end-pumped large-aperture gain media is reported. A ray tracing method has been used to evaluate the performance of the structure designed for maximum transmission efficiency and output beam profile homogeneity. Variable hollow-duct lengths as well as emanating angles of laser-diode-array have been taken into account.

  19. Corrosion protection with eco-friendly inhibitors

    Science.gov (United States)

    Shahid, Muhammad

    2011-12-01

    Corrosion occurs as a result of the interaction of a metal with its environment. The extent of corrosion depends on the type of metal, the existing conditions in the environment and the type of aggressive ions present in the medium. For example, CO3-2 and NO-3 produce an insoluble deposit on the surface of iron, resulting in the isolation of metal and consequent decrease of corrosion. On the other hand, halide ions are adsorbed selectively on the metal surface and prevent formation of the oxide phase on the metal surface, resulting in continuous corrosion. Iron, aluminum and their alloys are widely used, both domestically and industrially. Linear alkylbenzene and linear alkylbenzene sulfonate are commonly used as detergents. They have also been found together in waste water. It is claimed that these chemicals act as inhibitors for stainless steel and aluminum. Release of toxic gases as a result of corrosion in pipelines may lead in certain cases to air pollution and possible health hazards. Therefore, there are two ways to look at the relationship between corrosion and pollution: (i) corrosion of metals and alloys due to environmental pollution and (ii) environmental pollution as a result of corrosion protection. This paper encompasses the two scenarios and possible remedies for various cases, using 'green' inhibitors obtained either from plant extracts or from pharmaceutical compounds. In the present study, the effect of piperacillin sodium as a corrosion inhibitor for mild steel was investigated using a weight-loss method as well as a three-electrode dc electrochemical technique. It was found that the corrosion rate decreased as the concentration of the inhibitor increased up to 9×10-4 M 93% efficiency was exhibited at this concentration.

  20. Nontoxic corrosion inhibitors for N80 steel in hydrochloric acid

    OpenAIRE

    M. Yadav; Debasis Behera; Usha Sharma

    2016-01-01

    The purpose of this paper is to evaluate the protective ability of 1-(2-aminoethyl)-2-oleylimidazoline (AEOI) and 1-(2-oleylamidoethyl)-2-oleylimidazoline (OAEOI) as corrosion inhibitors for N80 steel in 15% hydrochloric acid, which may find application as eco-friendly corrosion inhibitors in acidizing processes in petroleum industry. Different concentrations of synthesized inhibitors AEOI and OAEOI were added to the test solution (15% HCl) and the corrosion inhibition of N80 steel in hydroch...

  1. Detection of corrosion by radiographic techniques

    International Nuclear Information System (INIS)

    Ahmad, M.; Ashraf, M.M.; Khurshid, U.

    2004-01-01

    Radiation processing technologies are playing an increasing role during manufacturing and subsequent use of everyday products. These technologies are now well established and are extensively practiced in industries, to ensure quality and safety of machinery. Corrosion reduces the operational life of the component, its efficiency and helps generate waste. There is an increasing need to detect and characterize the formation of corrosion in industrial components and assemblies at an early stage. Radiation methods and techniques are applied worldwide to examine defects and corrosion-formation in industrial components. For safety and economic reason, appropriate monitoring of the machinery and industrial components would help reduce accidental risks during operation and avoid production-losses. In the present study, X-ray and neutron-radiography techniques were applied for the inspection and evaluation of corrosion in metallic samples for thickness values of the order of 5 mm or less. Relative contrast at various degrees of metal corrosion product loss was computed theoretical and also measured experimentally by applying radiographic techniques. The relative contrast-sensitivity was also measured in two different ways by X-ray and neutron radiography, to compare the visibility of coarse and fine features. Thick metallic areas, free from sealant and variable paint thickness, were imaged with thermal neutrons beam. Low KV X-rays were also applied for imaging corrosion in metallic components. To optimize exposure-time at low KV in X-ray radiography, a medical film/screen combination was used. X-ray radiography approved to be the more promising technique for imaging of corrosion, as compared to neutron radiography. (author)

  2. Corrosion at system chimneys made of CrNi-steels

    Energy Technology Data Exchange (ETDEWEB)

    Pajonk, Gunther [Institute of Materials Testing of Northrhine-Westfalia, D-44285 Dortmund (Germany)

    2004-07-01

    Names like 'chimney' und 'funnel' usually identify flue gas devices made of bricks. Much less known is the fact that chimney elements are still manufactured from alloys. The following article describes the particular demands ruled by legislation on building pro-ducts, just as the consequences resulting from corrosion loads by flue gas condensates. Difficulties caused by manufacturing and construction are primarily discussed. Furthermore a test procedure is introduced that allows to catch and correlate corrosion loads and technical designs systematically to corrosion behaviour and service life of flue gas devices. For the first time a tool for active quality assurance has been given by this test rig allowing to recognize construction errors systematically. This way, manufacturers of system chimneys and flue liners are enabled to optimize their products applications going ahead to the respective requests of the market. (authors)

  3. The multimedia corrosion guide, 2. edition

    International Nuclear Information System (INIS)

    Audisio, S.

    2006-01-01

    Collecting the knowledge and experience of 26 international experts, the Multimedia Corrosion Guide is a reference book in the field of corrosion, for scientists, engineers, technicians and students. Also available in English, the second edition is more than just an update; it contains new chapters, new corrosion case studies and new smart functions. When knowledge is combined with experience, the result is a work of unprecedented quality and detail. Under the supervision of Professor Dr. S. Audisio of the Industrial Physical Chemistry Laboratory, INSA de Lyon, France, leading corrosion specialists from industry (Aerospatiale, CEA, EDF, ELF, Fragema, GDF, Pechiney, Renault, Rhone-Poulenc, Ugine...) have joined forces with experts from renowned French universities (INSA, UTC, ENSEEP, ENSCP, ENSAM...) to produce this book. In addition to the Corrosion Treatise, this program also contains a Case Studies Library, a corrosion database to which users can add their own experience base. New cases are automatically inserted alongside the existing ones, with the same selection criteria. Numerous other advanced functions make this second edition a unique, intelligent, professional and invaluable reference tool. (authors)

  4. Modelling of Corrosion Cracks

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    Modelling of corrosion cracking of reinforced concrete structures is complicated as a great number of uncertain factors are involved. To get a reliable modelling a physical and mechanical understanding of the process behind corrosion in needed.......Modelling of corrosion cracking of reinforced concrete structures is complicated as a great number of uncertain factors are involved. To get a reliable modelling a physical and mechanical understanding of the process behind corrosion in needed....

  5. Plant corrosion: prediction of materials performance

    International Nuclear Information System (INIS)

    Strutt, J.E.; Nicholls, J.R.

    1987-01-01

    Seventeen papers have been compiled forming a book on computer-based approaches to corrosion prediction in a wide range of industrial sectors, including the chemical, petrochemical and power generation industries. Two papers have been selected and indexed separately. The first describes a system operating within BNFL's Reprocessing Division to predict materials performance in corrosive conditions to aid future plant design. The second describes the truncation of the distribution function of pit depths during high temperature oxidation of a 20Cr austenitic steel in the fuel cladding in AGR systems. (U.K.)

  6. Metallic Corrosion. Vol. 1, 2 and 3

    International Nuclear Information System (INIS)

    1981-01-01

    The three volumes of the Congress Proceedings form the basis for the discussion of the prevailing problems in all areas of applied and basic research and their application in evera-day life and industry. The sequence of the contents of the three volumes corresponds to the scientific and technical Congress topics. Volume I contains basic and applied research on corrosion processes, testing and prevention Volume II starts with corrosion protection techniques, covers solutions to problems in specific industrial fields, and collects papers on economics, education, information and R and D programmes. Volume III contains all plenary lectures held on various topics. (orig.)

  7. Ultrasound appearance of chronic mammary duct ectasia

    Energy Technology Data Exchange (ETDEWEB)

    Duchesne, N. [Ottawa Hospital, Dept. of Radiology, Ottawa, Ontario (Canada)]. E-mail: nathalie_duchesne_22@yahoo.ca; Skolnik, S. [Univ. of Toronto, Dept. of Family Medicine, Toronto, Ontario (Canada); Bilmer, S. [Ottawa Hospital, Dept. of Radiology, Ottawa, Ontario (Canada)

    2005-12-15

    Mammary duct ectasia (MDE), also called periductal mastitis, mammary dysplasia, or plasma cell mastitis, is a benign condition of the mammary gland first described by Haagensen in 1951. The etiology of MDE is unknown and its pathogenesis still controversial; the periductal inflammation could be either the cause or the result of dilated damaged ducts. The process is usually bilateral and asymptomatic, with only a small percentage of patients presenting with symptoms that may include long course of tumour formation, usually subareolar breast lumps, nipple discharge, nipple retraction, mastalgia, and mammary abscess or fistulas. Mammographic presentation of MDE is well known; its features include periductal calcification, benign intraductal calcification, and retroareolar duct dilatation. The periductal calcification results from dystrophic calcification and forms calcified rings or very dense, oval, elongated calcifications, each with a central lucency representing the dilated duct. Intraductal calcifications of duct ectasia represent inspissated intraductal material and are typically of uniform high density, often needle-like, and occasionally branching. Occasionally, there are no mammographic findings, and the diagnosis must rely on sonographic features. Appearance of MDE on ultrasonography (US) depends on the stage of the disease and the contents of the dilated ducts. The acute presentation has been demonstrated in the literature more often than has its chronic counterpart. In the former, duct content can vary from anechoic to isoechoic with surrounding fatty tissue. In chronic MDE, episodes of inflammation are longer. This tends to result in secretions that have a more solid, cheesy texture, partly due to cholesterol crystals, foam cells, and inflammatory cells. For both types of MDE, the appearance can mimic high-grade ductal carcinoma in situ (DCIS) on US. In this essay, 2 chronic MDE cases are presented and their US appearance discussed. Our goal is to explore

  8. Ultrasound appearance of chronic mammary duct ectasia

    International Nuclear Information System (INIS)

    Duchesne, N.; Skolnik, S.; Bilmer, S.

    2005-01-01

    Mammary duct ectasia (MDE), also called periductal mastitis, mammary dysplasia, or plasma cell mastitis, is a benign condition of the mammary gland first described by Haagensen in 1951. The etiology of MDE is unknown and its pathogenesis still controversial; the periductal inflammation could be either the cause or the result of dilated damaged ducts. The process is usually bilateral and asymptomatic, with only a small percentage of patients presenting with symptoms that may include long course of tumour formation, usually subareolar breast lumps, nipple discharge, nipple retraction, mastalgia, and mammary abscess or fistulas. Mammographic presentation of MDE is well known; its features include periductal calcification, benign intraductal calcification, and retroareolar duct dilatation. The periductal calcification results from dystrophic calcification and forms calcified rings or very dense, oval, elongated calcifications, each with a central lucency representing the dilated duct. Intraductal calcifications of duct ectasia represent inspissated intraductal material and are typically of uniform high density, often needle-like, and occasionally branching. Occasionally, there are no mammographic findings, and the diagnosis must rely on sonographic features. Appearance of MDE on ultrasonography (US) depends on the stage of the disease and the contents of the dilated ducts. The acute presentation has been demonstrated in the literature more often than has its chronic counterpart. In the former, duct content can vary from anechoic to isoechoic with surrounding fatty tissue. In chronic MDE, episodes of inflammation are longer. This tends to result in secretions that have a more solid, cheesy texture, partly due to cholesterol crystals, foam cells, and inflammatory cells. For both types of MDE, the appearance can mimic high-grade ductal carcinoma in situ (DCIS) on US. In this essay, 2 chronic MDE cases are presented and their US appearance discussed. Our goal is to explore

  9. A radiographic study of nasopalatine duct cysts

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Chan Duck; Hwang, Eui Hwan; Lee, Sang Rae [Dept. of Oral Radiology, College of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    1993-02-15

    The purpose of this study was to evaluate the clinical and radiographic features of 35 cases of nasopalatine duct cyst by means of the analysis of periapical and/or occlusal radiograms in 35 persons visited the Department of Oral and Maxillofacial Radiology, School of Dentistry, Kyung Hee University and Chonbuk National University. The obtained results were as follows: 1. The incidence of nasopalatine duct cysts was higher in males (74.3%) than in females (25.7%). 2. The nasopalatine duct cysts were the most frequently occurred in the 4th decades (34.3%). The 6th and 7th decades (17.1%, 17.1%) were next in order to frequency followed by the 5th decades (14.3%), the 3rd decades (8.6%), the 2nd decades (5.7%), and 8th decades (2.9%). 3. In the signs and symptoms of nasopalatine duct cysts, 25.7% were swelling, 17.1% were swelling and tenderness, 20.0% were swelling and pain, and 37.2% were a symptom. 4. In the shape of nasopalatine duct cysts, 40.0% were round type, 48.6% 11.8% were heart type. 5. In symmetry of the nasopalatine duct cysts, 11.4% were 6-10 mm, 48.6% were 11-20 mm, 25.7% were 21-30 mm, and 14.3% were 31-40 mm. 6. In the periphery of nasopalatine duct cysts, 82.9% were distinct, 17.1% were relatively distinct. 7. In the change of root, 51.5% were intact, 17.1% were root divergence, 20.0% were root resorption, and 11.4% were root divergence and resorption.

  10. A radiographic study of nasopalatine duct cysts

    International Nuclear Information System (INIS)

    Jun, Chan Duck; Hwang, Eui Hwan; Lee, Sang Rae

    1993-01-01

    The purpose of this study was to evaluate the clinical and radiographic features of 35 cases of nasopalatine duct cyst by means of the analysis of periapical and/or occlusal radiograms in 35 persons visited the Department of Oral and Maxillofacial Radiology, School of Dentistry, Kyung Hee University and Chonbuk National University. The obtained results were as follows: 1. The incidence of nasopalatine duct cysts was higher in males (74.3%) than in females (25.7%). 2. The nasopalatine duct cysts were the most frequently occurred in the 4th decades (34.3%). The 6th and 7th decades (17.1%, 17.1%) were next in order to frequency followed by the 5th decades (14.3%), the 3rd decades (8.6%), the 2nd decades (5.7%), and 8th decades (2.9%). 3. In the signs and symptoms of nasopalatine duct cysts, 25.7% were swelling, 17.1% were swelling and tenderness, 20.0% were swelling and pain, and 37.2% were a symptom. 4. In the shape of nasopalatine duct cysts, 40.0% were round type, 48.6% 11.8% were heart type. 5. In symmetry of the nasopalatine duct cysts, 11.4% were 6-10 mm, 48.6% were 11-20 mm, 25.7% were 21-30 mm, and 14.3% were 31-40 mm. 6. In the periphery of nasopalatine duct cysts, 82.9% were distinct, 17.1% were relatively distinct. 7. In the change of root, 51.5% were intact, 17.1% were root divergence, 20.0% were root resorption, and 11.4% were root divergence and resorption.

  11. Sulfuric Acid Corrosion of Low Sb - Pb Battery Alloys | Ntukogu ...

    African Journals Online (AJOL)

    The corrosion properties of low Sb - Pb alloys developed for maintenance free motive power industrial batteries was studied by a bare grid constant current method and compared to those of the conventional Pb- 6% Sb alloy. Low Sb-Pb alloys with Se and As grain refiners were found to have higher corrosion rates than the ...

  12. An interesting and efficient green corrosion inhibitor for aluminium ...

    African Journals Online (AJOL)

    An interesting and efficient green corrosion inhibitor for aluminium from extracts of ... Journal Home > Vol 13, No 1 (2014) > ... possible applications in metal surface anodizing and surface coating in industries. Keywords: Moringa oleifera, Aluminium, Hydrochloric acid, Langmuir isotherm, Plant extracts, Corrosion inhibition ...

  13. Corrosion behaviour of mooring chain steel in seawater

    NARCIS (Netherlands)

    Zhang, X.; Noel, N.; Ferrari, G.; Hoogland, M.G.

    2016-01-01

    Failures of mooring lines on floating production, storage and offloading systems (FPSOs) raise concern to the offshore industry. Localized corrosion of mooring chain is regarded as one of main failure mechanisms. The project of Localized Mooring Chain Corrosion (LMCC) is aiming at studying the

  14. Microbiological corrosion of metals

    International Nuclear Information System (INIS)

    Vladislavlev, V.V.

    1992-01-01

    Problems is considered of development of the microbiological corrosion of the NPP equipment. The main attention is paid to the selective character of microbiological corrosion in zones of welded joints of austenitic steels. It is noted that the presence of technological defects promotes growth of corrosional damages. Methods for microbiological corrosion protection are discussed

  15. Management of Reinforcement Corrosion

    DEFF Research Database (Denmark)

    Küter, André; Geiker, Mette Rica; Møller, Per

    Reinforcement corrosion is the most important cause for deterioration of reinforced concrete structures, both with regard to costs and consequences. Thermodynamically consistent descriptions of corrosion mechanisms are expected to allow the development of innovative concepts for the management...... of reinforcement corrosion....

  16. The "flying" bile duct: avulsion of the common bile duct in a plane crash survivor.

    LENUS (Irish Health Repository)

    Mohan, H

    2012-02-01

    Blunt trauma is an unusual cause of extrahepatic bile duct injury. This is a case of a 51-year-old gentleman who sustained a significant seatbelt injury in a plane crash. Laparotomy, performed due to persistent abdominal pain, revealed that the common bile duct (CBD) was completely avulsed from the duodenum. Following insertion of drains and transfer to a hepatobiliary centre, the devascularised CBD was excised and replaced with a roux-en-y hepaticojejunostomy. Necrotic tissue was debrided from the pancreatic head. A persistent bile leak developed from the sub-hepatic drain. Repeat laparotomy revealed a bile leak from small ducts on the liver surface. Ligation of the ducts and bioglue sealing of the area were successfully performed. Subsequent to this a pancreatic fistula developed from the main pancreatic duct, which has since resolved. This unusual case illustrates the need for prompt recognition and early repair to optimise outcomes in traumatic CBD injury.

  17. ITER L 6 equatorial maintenance duct remote handling study

    International Nuclear Information System (INIS)

    Millard, J.

    1996-09-01

    The status and conclusions of a preliminary study of equatorial maintenance duct remote handling is reported. Due to issues with the original duct design a significant portion of the study had to be refocused on equatorial duct layout studies. The study gives an overview of some of the options for design of these ducts and the impact of the design on the equipment to work in the duct. To develop a remote handling concept for creating access through the ducts the following design tasks should be performed: define the operations sequences for equatorial maintenance duct opening and closing; review the remote handling requirements for equatorial maintenance duct opening and closing; design concept for door and pipe handling equipment and to propose preliminary procedures for material handling outsides the duct. 35 figs

  18. Effects of Variations in Salt-Spray Conditions on the Corrosion Mechanisms of an AE44 Magnesium Alloy

    Directory of Open Access Journals (Sweden)

    Holly J. Martin

    2010-01-01

    Full Text Available The understanding of how corrosion affects magnesium alloys is of utmost importance as the automotive and aerospace industries have become interested in the use of these lightweight alloys. However, the standardized salt-spray test does not produce adequate corrosion results when compared with field data, due to the lack of multiple exposure environments. This research explored four test combinations through three sets of cycles to determine how the corrosion mechanisms of pitting, intergranular corrosion, and general corrosion were affected by the environment. Of the four test combinations, Humidity-Drying was the least corrosive, while the most corrosive test condition was Salt Spray-Humidity-Drying. The differences in corrosivity of the test conditions are due to the various reactions needed to cause corrosion, including the presence of chloride ions to cause pit nucleation, the presence of humidity to cause galvanic corrosion, and the drying phase which trapped chloride ions beneath the corrosion by-products.

  19. Large Eddy Simulation of turbulence induced secondary flows in stationary and rotating straight square ducts

    Science.gov (United States)

    Sudjai, W.; Juntasaro, V.; Juttijudata, V.

    2018-01-01

    The accuracy of predicting turbulence induced secondary flows is crucially important in many industrial applications such as turbine blade internal cooling passages in a gas turbine and fuel rod bundles in a nuclear reactor. A straight square duct is popularly used to reveal the characteristic of turbulence induced secondary flows which consists of two counter rotating vortices distributed in each corner of the duct. For a rotating duct, the flow can be divided into the pressure side and the suction side. The turbulence induced secondary flows are converted to the Coriolis force driven two large circulations with a pair of additional vortices on the pressure wall due to the rotational effect. In this paper, the Large Eddy Simulation (LES) of turbulence induced secondary flows in a straight square duct is performed using the ANSYS FLUENT CFD software. A dynamic kinetic energy subgrid-scale model is used to describe the three-dimensional incompressible turbulent flows in the stationary and the rotating straight square ducts. The Reynolds number based on the friction velocity and the hydraulic diameter is 300 with the various rotation numbers for the rotating cases. The flow is assumed fully developed by imposing the constant pressure gradient in the streamwise direction. For the rotating cases, the rotational axis is placed perpendicular to the streamwise direction. The simulation results on the secondary flows and the turbulent statistics are found to be in good agreement with the available Direct Numerical Simulation (DNS) data. Finally, the details of the Coriolis effects are discussed.

  20. Application of Kelvin probe Force Microscopy (KFM) to evidence localized corrosion of over-aged aeronautical 2024 aluminum alloy

    OpenAIRE

    Radutoiu, Nicoleta; Alexis, Joël; Lacroix, Loïc; Abrudeanu, Marioara; Petit, Jacques-Alain

    2013-01-01

    International audience; The 2xxx serie aluminum alloys are characterized by good mechanical performances and low density, however they are susceptible to different forms of localized corrosion: pitting corrosion, intergranular corrosion and stress corrosion cracking. The 2024-T351 aluminum alloy is used in the aircraft industry for numerous applications such as fuselage and door skin. Corrosion damage of the material is also very detrimental for the structural integrity of the aircraft. The p...

  1. Study of the localized corrosion of over-aged aeronautical 2024 aluminum alloy. Kelvin probe Force Microscopy (KFM) application

    OpenAIRE

    Radutoiu , Nicoleta; Lacroix , Loïc; Alexis , Joël; Abrudeanu , Marioara; Petit , Jacques-Alain

    2012-01-01

    International audience; The 2xxx serie aluminum alloys are characterized by good mechanical performances and low density, however they are susceptible to different forms of localized corrosion: pitting corrosion, intergranular corrosion and stress corrosion cracking. The 2024-T351 aluminum alloy is used in the aircraft industry for numerous applications such as fuselage and door skin. Corrosion damage of the material is also very detrimental for the structural integrity of the aircraft. The p...

  2. Corrosion protection of low-carbon steel using exopolysaccharide coatings from Leuconostoc mesenteroides

    Science.gov (United States)

    Corrosion is one of the most serious and challenging problems faced worldwide by industry. This research investigates the inhibition of corrosive behavior of SAE1010 steel by bacterial exopolysaccharides. Electrochemical Impedance Spectroscopy was used to evaluate the corrosion inhibition of diffe...

  3. Electrochemical noise based corrosion monitoring: FY 2001 final report

    International Nuclear Information System (INIS)

    EDGAR, C.

    2001-01-01

    Underground storage tanks made of mild steel are used to contain radioactive waste generated by plutonium production at the Hanford Site. Corrosion of the walls of these tanks is a major issue. Corrosion monitoring and control are currently provided at the Hanford Site through a waste chemistry sampling and analysis program. In this process, tank waste is sampled, analyzed and compared to a selection of laboratory exposures of coupons in simulated waste. Tank wall corrosion is inferred by matching measured tank chemistries to the results of the laboratory simulant testing. This method is expensive, time consuming, and does not yield real-time data. Corrosion can be monitored through coupon exposure studies and a variety of electrochemical techniques. A small number of these techniques have been tried at Hanford and elsewhere within the DOE complex to determine the corrosivity of nuclear waste stored in underground tanks [1]. Coupon exposure programs, linear polarization resistance (LPR), and electrical resistance techniques have all been tried with limited degrees of success. These techniques are most effective for monitoring uniform corrosion, but are not well suited for early detection of localized forms of corrosion such as pitting and stress corrosion cracking (SCC). Pitting and SCC have been identified as the most likely modes of corrosion failure for Hanford Double Shell Tanks (DST'S) [2-3]. Over the last 20 years, a new corrosion monitoring system has shown promise in detecting localized corrosion and measuring uniform corrosion rates in process industries [4-20]. The system measures electrochemical noise (EN) generated by corrosion. The term EN is used to describe low frequency fluctuations in current and voltage associated with corrosion. In their most basic form, EN-based corrosion monitoring systems monitor and record fluctuations in current and voltage over time from electrodes immersed in an environment of interest. Laboratory studies and field

  4. Long Term Corrosion/Degradation Test Six Year Results

    Energy Technology Data Exchange (ETDEWEB)

    M. K. Adler Flitton; C. W. Bishop; M. E. Delwiche; T. S. Yoder

    2004-09-01

    The Subsurface Disposal Area (SDA) of the Radioactive Waste Management Complex (RWMC) located at the Idaho National Engineering and Environmental Laboratory (INEEL) contains neutron-activated metals from non-fuel, nuclear reactor core components. The Long-Term Corrosion/Degradation (LTCD) Test is designed to obtain site-specific corrosion rates to support efforts to more accurately estimate the transfer of activated elements to the environment. The test is using two proven, industry-standard methods—direct corrosion testing using metal coupons, and monitored corrosion testing using electrical/resistance probes—to determine corrosion rates for various metal alloys generally representing the metals of interest buried at the SDA, including Type 304L stainless steel, Type 316L stainless steel, Inconel 718, Beryllium S200F, Aluminum 6061, Zircaloy-4, low-carbon steel, and Ferralium 255. In the direct testing, metal coupons are retrieved for corrosion evaluation after having been buried in SDA backfill soil and exposed to natural SDA environmental conditions for times ranging from one year to as many as 32 years, depending on research needs and funding availability. In the monitored testing, electrical/resistance probes buried in SDA backfill soil will provide corrosion data for the duration of the test or until the probes fail. This report provides an update describing the current status of the test and documents results to date. Data from the one-year and three-year results are also included, for comparison and evaluation of trends. In the six-year results, most metals being tested showed extremely low measurable rates of general corrosion. For Type 304L stainless steel, Type 316L stainless steel, Inconel 718, and Ferralium 255, corrosion rates fell in the range of “no reportable” to 0.0002 mils per year (MPY). Corrosion rates for Zircaloy-4 ranged from no measurable corrosion to 0.0001 MPY. These rates are two orders of magnitude lower than those specified in

  5. Corrosion of Magnesium in Multimaterial System

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Vineet V.; Agnew, Sean

    2017-08-16

    The TMS Magnesium Committee has been actively involved in presenting cutting-edge research and development and the latest trends related to magnesium and its alloys to industry and academia. Topics including magnesium alloy development, applications, mechanism of deformation and corrosion, thermomechanical processing, modelling, etc. have been captured year after year through the Magnesium Technology symposium and conference proceedings at TMS and through special topics in JOM. Every year, based on the unanimous endorsement from the industry and academia, a topic is selected to address the latest developments within this subject in JOM. In continuation with last year’s coverage of Advances and Achievements in In-Situ Analysis of Corrosions and Structure–Property Relationship in Mg Alloys,[1] this year’s topic focuses on the Corrosion of Magnesium in Multimaterial Systems. Magnesium, the lightest of all the structural materials, has garnered much interest in the transportation, electronics packaging, defense equipments and industries alike and are more commonly being incorporated in multimaterial design concepts.[2-4] However, the application of the same is limited due to its highly corrosive nature, and understanding and mitigating the corrosion of magnesium has been a major research challenge.

  6. Characterization of flow in a scroll duct

    Science.gov (United States)

    Begg, E. K.; Bennett, J. C.

    1985-01-01

    A quantitative, flow visualization study was made of a partially elliptic cross section, inward curving duct (scroll duct), with an axial outflow through a vaneless annular cutlet. The working fluid was water, with a Re(d) of 40,000 at the inlet to the scroll duct, this Reynolds number being representative of the conditions in an actual gas turbine scroll. Both still and high speed moving pictures of fluorescein dye injected into the flow and illuminated by an argon ion laser were used to document the flow. Strong secondary flow, similar to the secondary flow in a pipe bend, was found in the bottom half of the scroll within the first 180 degs of turning. The pressure field set up by the turning duct was strong enough to affect the inlet flow condition. At 90 degs downstream, the large scale secondary flow was found to be oscillatory in nature. The exit flow was nonuniform in the annular exit. By 270 degs downstream, the flow appeared unorganized with no distinctive secondary flow pattern. Large scale structures from the upstream core region appeared by 90 degs and continued through the duct to reenter at the inlet section.

  7. Visualization of blood vessels by corrosion technique

    Directory of Open Access Journals (Sweden)

    Grzegorz Wróbel

    2017-09-01

    Full Text Available Corrosion technique is one of the basic and widely used methods of visualization of vascularization of organs in the anatomy of humans and animals. It consists in filling vascular (blood or lymph, wires or cavernous organs material, e.g., injection. Mass based on wax or putty material based on rubber, synthetic resin and subsequently etching the soft tissues. Ultimately obtained castings of these structures. The aim of the study was to evaluate the usefulness of this technique in morphological studies. In retrospect, corrosion technique has been used already in the seventeenth century, however, because of the use of filler materials such as water, liquid dyes, and even air, obtained anatomical specimens were unstable, therefore, did not yield the desired effect of the test. With time, however, the corrosion technician went through some modifications and new solutions in the embodiment and above all in the chemical composition of the filling material. In the twentieth century, they began to use compounds such as polyester resins, methyl methacrylate or polyvinyl chloride, the specific properties of these compounds allowed the visualization and consolidation of fine anatomic structures in the vascular system, the bronchial tree or the bile ducts. Extensive use of this technique in medicine, veterinary and comparative anatomy of vertebrates underlines its usefulness and the need to use.

  8. Preceedings of the International Congress (12th), Corrosion Control for Low-Cost Reliability, Held in Houston, Texas on September 19 -24, 1993. Volume 2. Process Industries Plant Operations.

    Science.gov (United States)

    1993-09-24

    abraded to no. 1000 emeryc paper, degreased with acetone and then electrolytically etched in 10C, Oxalic acid , with a current density of I Ampere per square...16 during Atmospheric Exposure by Means of Electrochemical Impedance Spectroscopy 400 Hydrothermal Properties of...329 040 The Effects of Acid Deposition on the Atmospheric Corrosion 461 Study of Corrosion Resistance of Electroless Ni-P Platings

  9. Squamous metaplasia of lactiferous ducts (SMOLD)

    International Nuclear Information System (INIS)

    Lo, G.; Dessauvagie, B.; Sterrett, G.; Bourke, A.G.

    2012-01-01

    The aim of this review is to illustrate the mammographic and sonographic appearances of squamous metaplasia of the lactiferous ducts (SMOLD) and to discuss the disease processes of this uncommon breast disease, which shows a strong correlation with smoking. The most common mammographic appearance is of a retro-areolar asymmetrical density. Ultrasonography of the symptomatic breast typically shows a retro-areolar, predominately medial, ill-defined, hypoechoic lesion with either abscess or sinus/fistula formation. Duct dilatation and continuity with lactiferous ducts is commonly seen. Increased vascularity is occasionally seen on colour Doppler ultrasound. Pathology tissue confirmation is always required and this can be by histology of a core biopsy or excision specimen, or fine-needle aspiration (FNA) cytology. Occasionally smears of an associated abundant nipple or sinus discharge may be of value.

  10. Salivary duct carcinoma: a Danish national study

    DEFF Research Database (Denmark)

    Breinholt, Helle; Elhakim, Mohammad Talal; Godballe, Christian

    2016-01-01

    BACKGROUND: To present the first national series of salivary duct carcinoma patients, including survival rates and an analysis of prognostic factors. METHODS: By merging three Danish nationwide registries that encompass an entire population, 34 patients diagnosed with salivary duct carcinoma from......-rank test. RESULTS: Salivary duct carcinoma showed an incidence of 0.04/100.000 inhabitants/year. Distant recurrence was seen in 52% of patients. Five-year overall survival, disease-specific survival and recurrence-free survival were 32%, 42% and 35%, respectively. Univariate analyses suggested that overall...... carcinoma incidence averages to two episodes per year in the entire Kingdom of Denmark. With half of patients in this study experiencing distant recurrences and only a third surviving at 5 years, prognosis is dismal. Advanced overall stage, vascular invasion and involved resection margins all seem...

  11. Corrosion-under-insulation (CUI) guidelines

    CERN Document Server

    Staff, European Federation of Corrosion; Winnik, S

    2014-01-01

    Corrosion under insulation (CUI) refers to the external corrosion of piping and vessels that occurs underneath externally clad/jacketed insulation as a result of the penetration of water. By its very nature CUI tends to remain undetected until the insulation and cladding/jacketing is removed to allow inspection or when leaks occur. CUI is a common problem shared by the refining, petrochemical, power, industrial, onshore and offshore industries. The European Federation of Corrosion (EFC) Working Parties WP13 and WP15 have worked to provide guidelines on managing CUI together with a number of major European refining, petrochemical and offshore companies including BP, Chevron-Texaco, Conoco-Phillips, ENI, Exxon-Mobil, IFP, MOL, Scanraff, Statoil, Shell, Total and Borealis. The guidelines within this document are intended for use on all plants and installations that contain insulated vessels, piping and equipment. The guidelines cover a risk-based inspection methodology for CUI, inspection techniques (including n...

  12. Microbiological Corrosion in Low Carbon Steels

    Directory of Open Access Journals (Sweden)

    O. Medina–Custodio

    2009-01-01

    Full Text Available The Microbiologically Induced Corrosion affects several industries, such as oil industry where it is estimated that 20% to 30% pipes failures are related with microorganism . The chemical reactions generate ions transfer, this validate the use of electrochemical techniques for its analysis. Coupons submerged in a nutritional medium with presence and absence of three different microorganisms during two periods, 48 hours and 28 days we restudied. Polarization resistance (Rp and Electrochemical Impedance Spectroscopy (EIS techniques we re applied to determine the corrosivity of the systems. The results show a greater corrosive effect of abiotic system, this indicates a microorganisms protection effect to the metal, opposite to the first hypothesis. This result was ratified observing surfaces coupons by using Scanning Electron Microscopy (SEM technique. A possible mechanism based on Evans – Tafel graph is proposed to explain inhibitor microorganism effect.

  13. Inhibition Effect of Deanol on Mild Steel Corrosion in Dilute ...

    African Journals Online (AJOL)

    NICOLAAS

    2014-06-23

    Jun 23, 2014 ... allows for extensive use as the material of construction in petro- leum industries .... steel specimens was investigated after mass-loss analysis ..... Ogbuliec, Inhibition of pseudo-anaerobic corrosion of oil pipeline steel in ...

  14. Evaluation of PEGIT duct connection system

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Brenner, Douglas E.; Sherman, Max H.; Dickerhoff, Darryl J.

    2003-08-01

    Most air duct system components are assembled in the field and are mechanically fastened by sheet metal screws (for sheet metal-to-sheet metal) or by drawbands (for flex duct-to-sheet metal). Air sealing is separate from this mechanical fastening and is usually achieved using tape or mastic products after mechanical fastening. Field observations have shown that mechanical fastening rarely meets code or manufacturers requirements and that sealing procedures are similarly inconsistent. To address these problems, Proctor Engineering Group (PEG) is developing a system of joining ducts (called PEGIT) that combines the mechanical fastening and sealing into a single self-contained procedure. The PEGIT system uses a shaped flexible seal between specially designed sheet metal duct fittings to both seal and fasten duct sections together. Figure 1 shows the inner duct fitting complete with rubber seal. This seal provides the air seal for the completed fitting and is shaped to allow the inner and outer fittings to slide together, and then to lock the fittings in place. The illustration in Figure 2 shows the approximate cross section of the rubber seal that shows how the seal has a lip that is angled backwards. This angled lip allows the joint to be pushed together by folding flat but then its long axis makes it stiff in the pulling apart direction. This study was undertaken to assist PEG in some of the design aspects of this system and to test the performance of the PEGIT system. This study was carried out in three phases. The initial phase evaluated the performance of a preliminary seal design for the PEGIT system. After the first phase, the seal was redesigned and this new seal was evaluated in the second phase of testing. The third phase performed more detailed testing of the second seal design to optimize the production tolerances of the sheet metal fittings. This report summarizes our findings from the first two phases and provides details about the third phase of testing.

  15. Percutaneous treatment of benign bile duct strictures

    Energy Technology Data Exchange (ETDEWEB)

    Koecher, Martin [Department of Radiology, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic)]. E-mail: martin.kocher@seznam.cz; Cerna, Marie [Department of Radiology, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Havlik, Roman [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Kral, Vladimir [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Gryga, Adolf [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Duda, Miloslav [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic)

    2007-05-15

    Purpose: To evaluate long-term results of treatment of benign bile duct strictures. Materials and methods: From February 1994 to November 2005, 21 patients (9 men, 12 women) with median age of 50.6 years (range 27-77 years) were indicated to percutaneous treatment of benign bile duct stricture. Stricture of hepatic ducts junction resulting from thermic injury during laparoscopic cholecystectomy was indication for treatment in one patient, stricture of hepaticojejunostomy was indication for treatment in all other patients. Clinical symptoms (obstructive jaundice, anicteric cholestasis, cholangitis or biliary cirrhosis) have appeared from 3 months to 12 years after surgery. Results: Initial internal/external biliary drainage was successful in 20 patients out of 21. These 20 patients after successful initial drainage were treated by balloon dilatation and long-term internal/external drainage. Sixteen patients were symptoms free during the follow-up. The relapse of clinical symptoms has appeared in four patients 9, 12, 14 and 24 months after treatment. One year primary clinical success rate of treatment for benign bile duct stricture was 94%. Additional two patients are symptoms free after redilatation (15 and 45 months). One patient is still in treatment, one patient died during secondary treatment period without interrelation with biliary intervention. The secondary clinical success rate is 100%. Conclusion: Benign bile duct strictures of hepatic ducts junction or biliary-enteric anastomosis are difficult to treat surgically and endoscopically inaccessible. Percutaneous treatment by balloon dilatation and long-term internal/external drainage is feasible in the majority of these patients. It is minimally invasive, safe and effective.

  16. Fluid flow in a spiral microfluidic duct

    Science.gov (United States)

    Harding, Brendan; Stokes, Yvonne

    2018-04-01

    We consider the steady, pressure driven flow of a viscous fluid through a microfluidic device having the geometry of a planar spiral duct with a slowly varying curvature and height smaller than width. For this problem, it is convenient to express the Navier-Stokes equations in terms of a non-orthogonal coordinate system. Then, after applying appropriate scalings, the leading order equations admit a relatively simple solution in the central region of the duct cross section. First-order corrections with respect to the duct curvature and aspect ratio parameters are also obtained for this region. Additional correction terms are needed to ensure that no slip and no penetration conditions are satisfied on the side walls. Our solutions allow for a top wall shape that varies with respect to the radial coordinate which allows us to study the flow in a variety of cross-sectional shapes, including trapezoidal-shaped ducts that have been studied experimentally. At leading order, the flow is found to depend on the local height and slope of the top wall within the central region. The solutions are compared with numerical approximations of a classical Dean flow and are found to be in good agreement for a small duct aspect ratio and a slowly varying and small curvature. We conclude that the slowly varying curvature typical of spiral microfluidic devices has a negligible impact on the flow in the sense that locally the flow does not differ significantly from the classical Dean flow through a duct having the same curvature.

  17. The Canadian residential duct and chimney survey

    Energy Technology Data Exchange (ETDEWEB)

    Fugler, D.

    2003-12-01

    A study was conducted in 1989 to better understand the thermal performance of ducts and chimneys in houses. The objective was to address the problems associated with insufficient airflow and backdrafting of combustion gases resulting from malfunctioning fans, furnaces and fireplaces. The Duct Test Rig was used to measure and recorded airflows and heat losses in a variety of ducts and chimneys in a representative mix of houses in Vancouver, Kelowna, Winnipeg, Calgary, Toronto, London, Montreal, Quebec City, Halifax, Fredericton and Ottawa. Bath, kitchen, clothes dryer and central vacuum exhaust fans were tested to determine how performance is affected by fan age, accumulations of dust, grease, bugs and installation methods. Results indicate that there is no statistical difference between axial or centrifugal fans. The greatest problem appeared to be with low flows, high leakage rates, and poor conditions of bathroom fans. Many kitchen fans were found to be blocked at the inlet by cooking grease. The exhaust flows depended greatly on the condition of the backdraft damper. Dryer exhaust airflow was typically less than the 75 L/s specified by manufacturers, but even old dryers performed relatively well. All types of chimneys were tested for different positive hood pressures, airflow lost through leakage, and thermal characteristics. Airflow was found to vary depending on the type and area of the flue and the presence of a cap. For heating systems, the low duct efficiency was due mostly to duct leakage, radiation losses and restrictive ducts and registers. The findings of this testing program are still valid today. 3 tabs.

  18. Emerging surface characterization techniques for carbon steel corrosion: a critical brief review

    OpenAIRE

    Dwivedi, D.; Lepkova, K.; Becker, T.

    2017-01-01

    Carbon steel is a preferred construction material in many industrial and domestic applications, including oil and gas pipelines, where corrosion mitigation using film-forming corrosion inhibitor formulations is a widely accepted method. This review identifies surface analytical techniques that are considered suitable for analysis of thin films at metallic substrates, but are yet to be applied to analysis of carbon steel surfaces in corrosive media or treated with corrosion inhibitors. The rev...

  19. Monitoring of corrosion damage using high-frequency guided ultrasonic waves

    OpenAIRE

    Chew, D.; Fromme, P.

    2014-01-01

    Due to adverse environmental conditions corrosion can develop during the life cycle of industrial structures, e.g., offshore oil platforms, ships, and desalination plants. Both pitting corrosion and generalized corrosion leading to wall thickness loss can cause the degradation of the integrity and load bearing capacity of the structure. Structural health monitoring of corrosion damage in difficult to access areas can in principle be achieved using high frequency guided waves propagating along...

  20. Characterization of corrosion products formed on steels in the first months of atmospheric exposure

    OpenAIRE

    Antunes Renato Altobelli; Costa Isolda; Faria Dalva Lúcia Araújo de

    2003-01-01

    The corrosion products of carbon steel and weathering steel exposed to three different types of atmospheres, at times ranging from one to three months, have been identified. The steels were exposed in an industrial site, an urban site (São Paulo City, Brazil), and a humid site. The effect of the steel type on the corrosion products formed in the early stages of atmospheric corrosion has been evaluated. The corrosion products formed at the various exposure locations were characterized by Raman...

  1. Detrimental effect of Air pollution, Corrosion on Building Materials and Historical Structures

    OpenAIRE

    N. Venkat Rao; M. Rajasekhar; Dr. G. Chinna Rao

    2016-01-01

    The economy of any country would be drastically changed if there were no corrosion. The annual cost of corrosion world wise is over 3 % of the worlds GDP. As pet the sources available, India losses $ 45 billion every year on account of corrosion of infrastructure, Industrial machinery and other historical heritage. Keeping this critical and alarming situation in view, this paper focuses on how all these forms of corrosion affect building materials and historical structures. It als...

  2. Prediction of metal corrosion using feed-forward neural networks

    International Nuclear Information System (INIS)

    Mahjani, M.G.; Jalili, S.; Jafarian, M.; Jaberi, A.

    2004-01-01

    The reliable prediction of corrosion behavior for the effective control of corrosion is a fundamental requirement. Since real world corrosion never seems to involve quite the same conditions that have previously been tested, using corrosion literature does not provide the necessary answers. In order to provide a methodology for predicting corrosion in real and complex situations, artificial neural networks can be utilized. Feed-forward artificial neural network (FFANN) is an information-processing paradigm inspired by the way the densely interconnected, parallel structure of the human brain process information.The aim of the present work is to predict corrosion behavior in critical conditions, such as industrial applications, based on some laboratory experimental data. Electrochemical behavior of stainless steel in different conditions were studied, using polarization technique and Tafel curves. Back-propagation neural networks models were developed to predict the corrosion behavior. The trained networks result in predicted value in good comparison to the experimental data. They have generally been claimed to be successful in modeling the corrosion behavior. The results are presented in two tables. Table 1 gives corrosion behavior of stainless-steel as a function of pH and CuSO 4 concentration and table 2 gives corrosion behavior of stainless - steel as a function of electrode surface area and CuSO 4 concentration. (authors)

  3. Bundle duct interaction studies for fuel assemblies

    International Nuclear Information System (INIS)

    Hsia, H.T.S.; Kaplan, S.

    1981-06-01

    It is known that the wire-wrapped rods and duct in an LMFBR are undergoing a gradual structural distortion from the initially uniform geometry under the combined effects of thermal expansion and irradiation induced swelling and creep. These deformations have a significant effect on flow characteristics, thus causing changes in thermal behavior such as cladding temperature and temperature distribution within a bundle. The temperature distribution may further enhance or retard irradiation induced deformation of the bundle. This report summarizes the results of the continuing effort in investigating the bundle-duct interaction, focusing on the need for the large development plant

  4. Acoustic power balance in lined ducts

    Science.gov (United States)

    Eversman, W.

    1979-01-01

    It is shown that the two common definitions of acoustic energy density and intensity in uniform unlined ducts carrying uniform flow are compatible to the extent that both energy densities can be used in an appropriate variational principle to derive the convected wave equation. When the duct walls are lined both energy densities must be modified to account for the wall energy density. This results in a new energy conservation equation which utilizes a modified definition of axial power and accounts for wall dissipation. Computations in specific cases demonstrate the validity of the modified acoustic energy relation.

  5. Local study of flow and low Reynolds thermal-hydraulic performance of a corrugated plane duct: application to plate heat exchangers

    International Nuclear Information System (INIS)

    Hugonnot, Patrick

    1989-01-01

    This research thesis addresses the local study of a flow in a corrugated plane duct by using experimental and numerical approaches on the one hand, and the experimental determination of thermal-hydraulic performance at low Reynolds number of different plate heat exchanger ducts on the other hand. Experimental visualisations of the local flow allowed regime transitions in 2D and 3D geometries to be determined. As far as the 2D duct is concerned, a wave profile optimisation is proposed, and the numerical study performed by using the TRIO software is in good agreement with experimental results. The optimised duct configuration can thus be envisaged for an industrial development. The determination of the friction coefficient and of the global heat exchange coefficient of different corrugated ducts allows plate exchangers to be sized on a wide range of Reynolds numbers. The respective influences of natural convection and of fluid thermal dependency on heat exchange have been studied [fr

  6. Cases of corrosion in power plant components at NTPC

    International Nuclear Information System (INIS)

    Sanyal, S.K.; Bhakta, U.C.; Sinha, Ashwini

    2000-01-01

    Power plants are one of the major industries suffering from severe corrosion problems resulting in substantial losses. The problem is becoming more prominent as the plants are getting older. NTPC as the leading power utility with very good performance track record, had been conscious of the menace of corrosion prevailing in the industry and had established a Research and Development Centre to cater to applied O and M needs of the plants. A specialized group has been involved in studying the corrosion related problems and recommending suitable cost effective solutions to such problems. The present paper aims at discussing various corrosion related analysis carried out at the Research and Development Centre of NTPC and the remedial measures suggested. The paper also describes some of the case studies of corrosion related failures with recommendations given for preventing such failures in future. (author)

  7. CASE REPORTS Thyroglossal duct cyst in adult Nigerians: a report ...

    African Journals Online (AJOL)

    MacBook

    Thyroglossal duct cyst (TGDC) is the most common paediatric midline neck lesion. It is rare ... modified Sistrunk's operation and histology confirmed the diagnosis of thyroglossal cyst. ... surgical procedure for the treatment of thyroglossal duct ...

  8. Liver and Bile Duct Cancer—Health Professional Version

    Science.gov (United States)

    Liver cancer includes two major types: hepatocellular carcinoma (HCC) and intrahepatic bile duct cancer, also known as cholangiocarcinoma. Find evidence-based information on liver and bile duct cancer treatment, causes and prevention, screening, research, genomics and statistics.

  9. New concept of the buildup factor in bent ducts

    International Nuclear Information System (INIS)

    Faik Ouahab, Z.; Jehouani, A.; Groetz, J.-E.

    2011-01-01

    A major problem confronting the radiation shielding designer is the accurate determination of neutron streaming through various penetrations in walls, ducts and mazes. The previous studies on neutron transmission were performed through empty ducts. The aim of this work is to evaluate the neutron transmission probability through a filled bent duct and the proposition of a new concept of the buildup factor for neutrons in multilegged ducts. An angular biaising technique is used in the Monte Carlo simulations to accelerate the calculation convergence. Results are first compared with those obtained by the MCNPX code. For an empty bent duct, the neutron transmission is only due to the neutron reflection on the duct wall. For a filled duct, the major contribution is due to the scattering on the atoms filling the duct.

  10. Corrosion principles and surface modification

    International Nuclear Information System (INIS)

    Kruger, J.

    1982-01-01

    This chapter examines the important strategies provided by the newer ideas of corrosion science and engineering that surface modification techniques must utilize to help prevent corrosion, especially the most damaging kind of aqueous corrosion, localized corrosion. Provides a brief introduction to the principles underlying the phenomenon of corrosion in order to use them to discuss surface modification strategies to combat corrosion. Discusses the electrochemistry of corrosion; the thermodynamics of corrosion; the kinetics of corrosion; thermodynamic strategies; and kinetic strategies (formation of more protective passive films; resistance to breakdown; ductility; repassivation)

  11. Solitary intrahepatic bile-duct cyst presenting with Jaundice

    International Nuclear Information System (INIS)

    Park, Jeong Mi; Chun, Ki Sung; Ha, Hyun Kwon; Shinn, Kyung Sub; Bahk, Yong Whee; Kim, Jun Gi

    1989-01-01

    Caroli's disease is an uncommon condition, and characterized by congenital segmental saccular dilatation of intrahepatic bile ducts. A case of Caroli's disease, manifested by only a large communicating cystic dilatation of left intrahepatic bile duct and causing extrinsic pressure over the extrahepatic bile duct, is presented. The patient was 43-year-old housewife, hospitalized because of abdominal distension and severe jaundice. To relieve jaundice and alleviate surgical intervention, percutaneous drainage of the bile-duct cyst preceded surgery

  12. Prediction of Corrosion of Advanced Materials and Fabricated Components

    Energy Technology Data Exchange (ETDEWEB)

    A. Anderko; G. Engelhardt; M.M. Lencka (OLI Systems Inc.); M.A. Jakab; G. Tormoen; N. Sridhar (Southwest Research Institute)

    2007-09-29

    The goal of this project is to provide materials engineers, chemical engineers and plant operators with a software tool that will enable them to predict localized corrosion of process equipment including fabricated components as well as base alloys. For design and revamp purposes, the software predicts the occurrence of localized corrosion as a function of environment chemistry and assists the user in selecting the optimum alloy for a given environment. For the operation of existing plants, the software enables the users to predict the remaining life of equipment and help in scheduling maintenance activities. This project combined fundamental understanding of mechanisms of corrosion with focused experimental results to predict the corrosion of advanced, base or fabricated, alloys in real-world environments encountered in the chemical industry. At the heart of this approach is the development of models that predict the fundamental parameters that control the occurrence of localized corrosion as a function of environmental conditions and alloy composition. The fundamental parameters that dictate the occurrence of localized corrosion are the corrosion and repassivation potentials. The program team, OLI Systems and Southwest Research Institute, has developed theoretical models for these parameters. These theoretical models have been applied to predict the occurrence of localized corrosion of base materials and heat-treated components in a variety of environments containing aggressive and non-aggressive species. As a result of this project, a comprehensive model has been established and extensively verified for predicting the occurrence of localized corrosion as a function of environment chemistry and temperature by calculating the corrosion and repassivation potentials.To support and calibrate the model, an experimental database has been developed to elucidate (1) the effects of various inhibiting species as well as aggressive species on localized corrosion of nickel

  13. Persistent Mullerian Duct Syndrome (PMDS With Large Intraabdominal Seminoma

    Directory of Open Access Journals (Sweden)

    Della Harigovind

    2017-07-01

    Full Text Available Persistent Mullerian Duct Syndrome, a form of male pseudohermaphroditism is characterized by the presence of the Mullerian duct derivatives in an otherwise phenotypically as well as genotypically normal male. We report a case of large intra abdominal seminoma in a male patient with cryptorchidism, along with persistence of Mullerian duct derivatives (uterus.

  14. Common Bile Duct Perforation Due to Tuberculosis: A Case Report

    Directory of Open Access Journals (Sweden)

    Razman Jarmin

    2004-10-01

    Full Text Available A young man with HIV presented with biliary peritonitis secondary to spontaneous common bile duct perforation. Investigation revealed that the perforation was due to Mycobacterium tuberculosis. Tuberculosis of the bile duct is uncommon and usually presents with obstructive jaundice due to stricture. Bile duct perforation due to tuberculosis is extremely rare. Its management is discussed.

  15. Common Bile Duct Perforation Due to Tuberculosis: A Case Report

    OpenAIRE

    Razman Jarmin; Shaharin Shaharuddin

    2004-01-01

    A young man with HIV presented with biliary peritonitis secondary to spontaneous common bile duct perforation. Investigation revealed that the perforation was due to Mycobacterium tuberculosis. Tuberculosis of the bile duct is uncommon and usually presents with obstructive jaundice due to stricture. Bile duct perforation due to tuberculosis is extremely rare. Its management is discussed.

  16. Iatrogenic injury of an aberrant right posterior sectoral bile duct

    African Journals Online (AJOL)

    (Figs 1 and 2). A week later, an endoscopic retrograde cholangiopancreatography. (ERCP) examination was performed. This showed no filling of the right posterior sectoral ducts but normal opacification of the other ducts. (Figs 3a and b). These findings led to the diagnosis of an aberrant right posterior sectoral bile duct that ...

  17. A case of fascioliasis in common bile duct

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Soo Youn; Park, Cheol Min; Chung, Kyu Byung; Lee, Chang Hong; Park, Seung Chul; Choi, Sang Yong; Lim, Han Jong [Korea University College of Medicine, Seoul (Korea, Republic of)

    1989-10-15

    A case of Fascioliasis of common bile duct is confirmed by visualization of adult fluke. Fascioliasis caused by Fasciola hepatica, is common parasitic disease in cattle and sheep. Human is an accidental host. ERCP demonstrated irregular linear conglomerated filling defects in common bile duct. Through surgical intervention, we found adult flukes of F. hepatica and adenomatous hyperplasia of common bile duct.

  18. A case of fascioliasis in common bile duct

    International Nuclear Information System (INIS)

    Ham, Soo Youn; Park, Cheol Min; Chung, Kyu Byung; Lee, Chang Hong; Park, Seung Chul; Choi, Sang Yong; Lim, Han Jong

    1989-01-01

    A case of Fascioliasis of common bile duct is confirmed by visualization of adult fluke. Fascioliasis caused by Fasciola hepatica, is common parasitic disease in cattle and sheep. Human is an accidental host. ERCP demonstrated irregular linear conglomerated filling defects in common bile duct. Through surgical intervention, we found adult flukes of F. hepatica and adenomatous hyperplasia of common bile duct

  19. Internal radiotherapy for hilar bile duct cancer

    International Nuclear Information System (INIS)

    Ryu, Munemasa; Ogino, Takashi; Konishi, Hiroshi

    1999-01-01

    By December 1998, 24 patients with non-resected hilar bile duct cancer (mean age of 74) had received bile duct intracavitary irradiation and 13 patients with residual cancer after resection of hilar bile duct cancer had received postoperative intracavitary irradiation. After they were externally irradiated 30 Gy in total by 15 fractions (2 Gy/time, 5 times in a week), intracavitary irradiation using 192-Ir was given 5 times in total (2 times in a week) from 3 weeks after external irradiation under the condition which dose became 8 Gy in depth of 10 mm from radiation source. The cases of postoperative irradiation had 3 times in total. As for 20 patients of non-resected hilar bile duct cancer without metastasis, 50% survival time was 265 days and there was no 5 year survivor. Fifty percents survival time of 4 patients with metastasis was 113 days. The effect of local control was recognized in 20 patients (83.3%). In 13 patients of postoperative irradiation, 50% survival time was 554 days, and survival rate of 3 years was 28%. (K.H.)

  20. 46 CFR 116.610 - Ventilation ducts.

    Science.gov (United States)

    2010-10-01

    ... incidental to its installation, must be made of noncombustible material. (c) Combustibles and other foreign materials are not allowed within ventilation ducts. However, metal piping and electrical wiring installed in... the wiring does not interfere with the operation of fire dampers. Electrical wiring and piping may not...

  1. Calcium influx pathways in rat pancreatic ducts

    DEFF Research Database (Denmark)

    Hug, M J; Pahl, C; Novak, I

    1996-01-01

    A number of agonists increase intracellular Ca2+ activity, [Ca2+]i, in pancreatic ducts, but the influx/efflux pathways and intracellular Ca2+ stores in this epithelium are unknown. The aim of the present study was to characterise the Ca2+ influx pathways, especially their pH sensitivity, in nati...

  2. MR findings in thyroglossal duct cysts

    International Nuclear Information System (INIS)

    Blandino, A.; Salvi, L.; Chirico, G.; Scribano, E.; Longo, M.; Pandolfo, I.

    1990-01-01

    Two patients with thyroglossal duct cysts have been studied with CT and MR. The typical CT feature of these cystic upper-neck lesions are depicted in literature, conversely MR findings are not well known. The homogeneous high intensity on T1-weighted images, higher than simple cyst or fluid, is the most typical feature of the thyroglossal cyst. (author). 12 refs.; 5 figs

  3. [Bile duct lesions in laparoscopic cholecystectomy].

    Science.gov (United States)

    Siewert, J R; Ungeheuer, A; Feussner, H

    1994-09-01

    Laparoscopic cholecystectomy is both resulting in a slightly higher incidence of biliary lesions and a change of prevalence of the type of lesions. Damage to the biliary system occurs in 4 different types: The most severe case is the lesion with a structural defect of the hepatic or common bile duct with (IVa) or without (IVb) vascular injury. Tangential lesions without structural loss of the duct should be denominated as type III (IIIa with additional lesion to the vessels, type IIIb without). Type II comprehends late strictures without obvious intraoperative trauma to the duct. Type I includes immediate biliary fistulae of usually good prognosis. The increasing prevalence of structural defects of the bile ducts appears to be a peculiarity of laparoscopic cholecystectomy necessitating highly demanding operative repair. In the majority of cases, hepatico-jejunostomy or even intraparenchymatous anastomoses are required. Adaptation of well proven principles of open surgery is the best prevention of biliary lesions in laparoscopic cholecystectomy as well as the readiness to convert early to the open procedure.

  4. Depressurization test on hot gas duct

    International Nuclear Information System (INIS)

    Tanihira, Masanori; Kunitomi; Kazuhiko; Inagaki, Yoshiyuki; Miyamoto, Yoshiaki; Sato, Yutaka.

    1989-05-01

    To study the integrity of internal structures and the characteristics in a hot gas duct under the rapid depressurization accident, depressurization tests have been carried out using a test apparatus installed the hot gas duct with the same size and the same structures as that of the High Temperature Engineering Test Reactor (HTTR). The tests have been performed with three parameters: depressurization rate (0.14-3.08 MPa/s) determined by orifice diameter, area of the open space at the slide joint (11.9-2036 mm 2 ), and initial pressure (1.0-4.0 MPa) filled up in a pressure vessel, by using nitrogen gas and helium gas. The maximum pressure difference applied on the internal structures of the hot gas duct was 2.69 MPa on the liner tube and 0.45 MPa on the separating plate. After all tests were completed, the hot gas duct which was used in the tests was disassembled. Inspection revealed that there were no failure and no deformation on the internal structures such as separating plates, insulation layers, a liner tube and a pressure tube. (author)

  5. Whistler instability in a magnetospheric duct

    International Nuclear Information System (INIS)

    Talukdar, I.; Tripathi, V.K.; Jain, V.K.

    1989-01-01

    A whistler wave propagating through a preformed magnetospheric duct is susceptible to growth/amplification by an electron beam. The interaction is non-local and could be of Cerenkov or slow-cyclotron type. First-order perturbation theory is employed to obtain the growth rate for flat and Gaussian beam densities. (author)

  6. Monitoring Microbially Influenced Corrosion

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    and diffusional effects and unreliable corrosion rates, when biofilm and ferrous sulphide corrosion products cover the steel surface. Corrosion rates can be overestimated by a factor of 10 to 100 by electrochemical techniques. Weight loss coupons and ER are recommended as necessary basic monitoring techniques......Abstract Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria (SRB). The applicability and reliability of a number of corrosion monitoring techniques for monitoring MIC has been evaluated in experiments....... EIS might be used for detection of MIC as the appearance of very large capacitances can be attributed to the combined ferrous sulphide and biofilm formation. Capacitance correlates directly with sulphide concentration in sterile sulphide media. Keywords: Corrosion monitoring, carbon steel, MIC, SRB...

  7. SRB seawater corrosion project

    Science.gov (United States)

    Bozack, M. J.

    1991-01-01

    The corrosion behavior of 2219 aluminum when exposed to seawater was characterized. Controlled corrosion experiments at three different temperatures (30, 60 and 100 C) and two different environments (seawater and 3.5 percent salt solution) were designed to elucidate the initial stages in the corrosion process. It was found that 2219 aluminum is an active catalytic surface for growth of Al2O3, NaCl, and MgO. Formation of Al2O3 is favored at lower temperatures, while MgO is favored at higher temperatures. Visible corrosion products are formed within 30 minutes after seawater exposure. Corrosion characteristics in 3.5 percent salt solution are different than corrosion in seawater. Techniques utilized were: (1) scanning electron microscopy, (2) energy dispersive x-ray spectroscopy, and (3) Auger electron spectroscopy.

  8. Chemical cleaning, decontamination and corrosion

    International Nuclear Information System (INIS)

    Gadiyar, H.S.; Das Chintamani; Gaonkar, K.B.

    1991-01-01

    Chemical cleaning of process equipments and pipings in chemical/petrochemical industries is necessitated for improving operation, for preventing premature failures and for avoiding contamination. In developing a chemical formulation for cleaning equipments, the important aspects to be considered include (i) effective removal of corrosion products and scales, (ii) minimum corrosion of the base metal, (iii) easy to handle chemicals and (iv) economic viability. As on date, a wide variety of chemical formulations are available, many of them are either proprietory or patented. For evolving an effective formulation, knowledge of the oxides of various metals and alloys on the one hand and acid concentration, complexing agents and inhibitors to be incorporated on the other, is quite essential. Organic acids like citric acid, acetic acid and formic acid are more popular ones, often used with EDTA for effective removal of corrosion products from ferrous components. The report enumerates some of the concepts in developing effective formulations for chemical cleaning of carbon steel components and further, makes an attempt to suggest simple formulations to be developed for chemical decontamination. (author). 6 refs., 3 fi gs., 4 tabs

  9. Tolerance of bile duct to intraoperative irradiation

    International Nuclear Information System (INIS)

    Sindelar, W.F.; Tepper, J.; Travis, E.L.

    1982-01-01

    In order to determine the effects of intraoperative radiation therapy of the bile duct and surrounding tissues, seven adult dogs were subjected to laparotomy and intraoperative irradiation with 11 MeV electrons. Two animals were treated at each dose level of 2000, 3000, and 4500 rads. A single dog which received a laparotomy and sham irradiation served as a control. The irradiation field consisted of a 5 cm diameter circle encompassing the extrahepatic bile duct, portal vein, hepatic artery, and lateral duodenal wall. The animals were followed clinically for mor than 18 months after treatment, and autopsies were performed on dogs that died to assess radiation-induced complications or tissue damage. All dogs developed fibrosis and mural thickening of the common duct, which appeared by 6 weeks following irradiation and which was dose-related, being mild at low doses and more severe at high doses. Hepatic changes were seen as early as 6 weeks after irradiation, consisting of periportal inflammation and fibrosis. The hepatic changes appeared earliest at the highest doses. Frank biliary cirrhosis eventually developed at all dose levels. Duodenal fibrosis appeared in the irradiation portal, being most severe at the highest doses and in some animals resulting in duodenal obstruction. No changes were observed in irradiated portions of portal vein and hepatic artery at any dose level. It was concluded that intraoperative radiation therapy delivered to the region of the common duct leads to ductal fibrosis, partial biliary obstruction with secondary hepatic changes, and duodenal fibrosis if bowel wall is included in the field. Clinical use of intraoperative radiation therapy to the bile duct in humans may require routine use of biliary and duodenal bypass to prevent obstructive complications

  10. Are Ducted Mini-Splits Worth It?

    Energy Technology Data Exchange (ETDEWEB)

    Winkler, Jonathan M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Maguire, Jeffrey B [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Metzger, Cheryn E. [Pacific Northwest National Laboratory; Zhang, Jason [Pacific Northwest National Laboratory

    2018-02-01

    Ducted mini-split heat pumps are gaining popularity in some regions of the country due to their energy-efficient specifications and their ability to be hidden from sight. Although product and install costs are typically higher than the ductless mini-split heat pumps, this technology is well worth the premium for some homeowners who do not like to see an indoor unit in their living area. Due to the interest in this technology by local utilities and homeowners, the Bonneville Power Administration (BPA) has funded the Pacific Northwest National Laboratory (PNNL) and the National Renewable Energy Laboratory (NREL) to develop capabilities within the Building Energy Optimization (BEopt) tool to model ducted mini-split heat pumps. After the fundamental capabilities were added, energy-use results could be compared to other technologies that were already in BEopt, such as zonal electric resistance heat, central air source heat pumps, and ductless mini-split heat pumps. Each of these technologies was then compared using five prototype configurations in three different BPA heating zones to determine how the ducted mini-split technology would perform under different scenarios. The result of this project was a set of EnergyPlus models representing the various prototype configurations in each climate zone. Overall, the ducted mini-split heat pumps saved about 33-60% compared to zonal electric resistance heat (with window AC systems modeled in the summer). The results also showed that the ducted mini-split systems used about 4% more energy than the ductless mini-split systems, which saved about 37-64% compared to electric zonal heat (depending on the prototype and climate).

  11. CT findings of thyroglossal duct cyst

    International Nuclear Information System (INIS)

    Kim, Dong Oh; Kim, Hong Soo; So, Hyun Soon; Nam, Mee Young; Choi, Jae Ho; Rhee, Hak Song

    1995-01-01

    The purpose of this study was to evaluate the CT findings of thyroglossal duct cysts. Sixteen patients with pathologically proved thyroglossal duct cysts were included in the study. CT scans were assessed retrospectively for shape, size, location, density of the central portions, septations, rim enhancement, changes in the adjacent fascial planes and investment within the strap muscles in the infrahyoid cysts. Thirteen cases of thyroglossal duct cysts were seen as round or oval cystic masses, two cases of them were seen as irregular-shaped lobulated cystic masses, and one case was seen as ovoid soft tissue mass. The cysts were from 1.4 to 5.7 cm in diameter (mean, 2.6 cm). The cyst was infrahyoid in 15 cases and suprahyoid in one case. The cyst was located in midline in eight cases, off midline in four cases, and both midline and off midline in four cases. The density of the central portions ranged from 15 to 82HU (mean, 32HU). Septations were noted in four cases. Rim enhancement was seen in 14 cases (93%), and heterogeneously enhancing soft tissue mass was seen in one case. In four cases, abnormal fascial planes were observed. All but one of the infrahyoid cysts (14/15) were embedded within the strap muscles, and one case of them was located anteriorly to strap muscles. CT permits one to make the diagnosis a thyroglossal duct cyst with a high degree of accuracy, as it can differentiate thyroglossal duct cysts from the other anterior neck masses by their typical location, characteristic morphology, and investment within the strap muscles

  12. Duct-to-duct biliary reconstruction after radical resection of Bismuth IIIa hilar cholangiocarcinoma.

    Science.gov (United States)

    Wu, Wen-Guang; Gu, Jun; Dong, Ping; Lu, Jian-Hua; Li, Mao-Lan; Wu, Xiang-Song; Yang, Jia-Hua; Zhang, Lin; Ding, Qi-Chen; Weng, Hao; Ding, Qian; Liu, Ying-Bin

    2013-04-21

    At present, radical resection remains the only effective treatment for patients with hilar cholangiocarcinoma. The surgical approach for R0 resection of hilar cholangiocarcinoma is complex and diverse, but for the biliary reconstruction after resection, almost all surgeons use Roux-en-Y hepaticojejunostomy. A viable alternative to Roux-en-Y reconstruction after radical resection of hilar cholangiocarcinoma has not yet been proposed. We report a case of performing duct-to-duct biliary reconstruction after radical resection of Bismuth IIIa hilar cholangiocarcinoma. End-to-end anastomosis between the left hepatic duct and the distal common bile duct was used for the biliary reconstruction, and a single-layer continuous suture was performed along the bile duct using 5-0 prolene. The patient was discharged favorably without biliary fistula 2 wk later. Evidence for tumor recurrence was not found after an 18 mo follow-up. Performing bile duct end-to-end anastomosis in hilar cholangiocarcinoma can simplify the complex digestive tract reconstruction process.

  13. Developing flow in S-shaped ducts. 2: Circular cross-section duct

    Science.gov (United States)

    Taylor, A. M. K. P.; Whitelaw, J. H.; Yianneskis, M.

    1984-01-01

    Laser-Doppler velocimetry measured the laminar and turbulent streamwise flow in a S-duct. The wall pressure distribution and one component of cross-stream velocity were also obtained for the turbulent flow case. Boundary layers near the duct inlet were about 25 percent of the hydraulic diameter in the laminar flow and varied around the periphery of the pipe between 10 percent and 20 percent in turbulent flow. Pressure-driven secondary flows develop in the first half of the S-duct and are attenuated and reversed in the second half. For both Reynolds numbers there is a region near the outer wall of the second half of the duct where the sign of the radial vorticity results in an enforcement of the secondary flow which was established in the first half of the S-duct. The core flow migrates, for both Reynolds numbers, to the outside wall of the first half and lies towards the inside wall of the second half of the S-duct at the outlet. The thinner inlet boundary layers in the turbulent flow give rise to weaker secondary motion.

  14. Coatings and Corrosion Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The mission of the Coatings and Corrosion Laboratory is to develop and analyze the effectiveness of innovative coatings test procedures while evaluating the...

  15. Boric acid corrosion of low alloy steel

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R.; White, G.; Collin, J.; Marks, C. [Dominion Engineering, Inc., Reston, Virginia (United States); Reid, R.; Crooker, P. [Electric Power Research Inst., Palo Alto, California (United States)

    2010-07-01

    In the last decade, the industry has been aware of a potential loss of coolant accident (LOCA) per the following scenario: primary water stress corrosion cracking (PWSCC) of a primary system component or weld leads to a coolant leak, the coolant corrodes a low alloy steel structural component (e.g., the reactor vessel (RV) or the reactor vessel head (RVH)), and corrosion degrades the pressure boundary leading to a loss of coolant accident. The industry has taken several steps to address this concern, including replacement of the most susceptible components (RVH replacement), enhanced inspection (both NDE of components and visual inspections for boric acid deposits), and safety analyses to determine appropriate inspection intervals. Although these measures are generally thought to have adequately addressed this issue, there have been some uncertainties in the safety analyses which the industry has sought to address in order to quantify the extent of conservatism in the safety analyses. Specifically, there has been some uncertainty regarding the rate of boric acid corrosion under various conditions which might arise due to a PWSCC leak and the extent to which boric acid deposits are retained near the leak under various geometries. This paper reviews the results of the Electric Power Research Institute (EPRI) Materials Reliability Program (MRP) boric acid corrosion (BAC) test programs conducted over the last 8 years, focusing on the most recent results of full-scale mockup testing of CRDM nozzle and bottom mounted nozzle (BMN) configurations. The main purpose of this presentation is to provide an overview of the latest understanding of the risk of boric acid corrosion as it is informed by the results of the testing conducted over the last eight years. The rate of boric acid corrosion has been found to be a function of many factors, including initial chemistry, the extent of concentration due to boiling, the temperature at which concentration takes place, the velocity

  16. Long-term follow-up after choledochojejunostomy for bile duct stones with complex clearance of the bile duct

    NARCIS (Netherlands)

    Gouma, D. J.; Konsten, J.; Soeters, P. B.; Von Meyenfeldt, M.; Obertop, H.

    1989-01-01

    In this retrospective study, the long-term follow-up of patients undergoing choledochojejunostomy (Roux-en-Y) for bile duct stones with complex clearance of the bile duct is evaluated. Bile duct exploration and subsequent choledochojejunostomy (Roux-en-Y) was performed in 43 patients (median age 67

  17. Experimental and Theoretical Investigation of Impinging Jet Ventilation at Different Cross Sectional Area of Supply Air Duct

    Directory of Open Access Journals (Sweden)

    Ala'a Abbas Mahdi

    2018-03-01

    Full Text Available  An experimental and computational analysis of temperature and velocity distribution in an office room have been studied. Office room of dimensions (3m x 1.75m x 3m with two cross sectional types of supply air duct in the experimental part and three different cross sectional types of supply air duct in the theoretical part is usual as a tested model. The RNG k-  turbulence model was employed to solve the governing equations numerically and validated by comparing the numerical results with experimental data. The impinging jet concept has been proposed as a new ventilation strategy for use in office and industrial buildings. The present work focuses on evaluating the performance of a new impinging jet ventilation. In a theoretical study three types of supply air duct are adopted which are square supply air duct (Type-I, semi-elliptic supply air duct (Type-II and rectangle supply air duct (Type-III for two cases of air outlet terminal height from room foot level, 0.14h (case-I & 0.1h (case-II. The third type (rectangle duct gives lowest effective and discomfort conditions when compared with the other two types. This study investigated a number of factors influencing draught discomfort and temperature stratification in an office environment equipped with impinging jet ventilation IJV. The factors considered to be: shape of the air supply device, supply airflow rate and supply air temperature. Acceptable Air Distribution Performance Index (ADPI, effective temperature, and ventilation efficiency obtained that the square cross sectional area of supply air duct at 0.1h (case-II height from foot level gives more acceptable indoor air quality and human thermal comfort when compared with the other types. Also, this type gives good air distribution system not only promotes a comfortable and healthy environment for occupants, but also contributes to energy conservation.

  18. CFD investigating the air ingress accident for a HTGR simulation of graphite corrosion oxidation

    International Nuclear Information System (INIS)

    Ferng, Y.M.; Chi, C.W.

    2012-01-01

    Highlights: ► A CFD model is proposed to investigate graphite oxidation corrosion in the HTR-10. ► A postulated air ingress accident is assumed in this paper. ► Air ingress flowrate is the predicted result, instead of the preset one. ► O 2 would react with graphite on pebble surface, causing the graphite corrosion. ► No fuel exposure is predicted to be occurred under the air ingress accident. - Abstract: Through a compressible multi-component CFD model, this paper investigates the characteristics of graphite oxidation corrosion in the HTR-10 core under the postulated accident of gas duct rupture. In this accident, air in the steam generator cavity would enter into the core after pressure equilibrium is achieved between the core and the cavity, which is also called as the air ingress accident. Oxygen in the air would react with graphite on pebble surface, subsequently resulting in oxidation corrosion and challenging fuel integrity. In this paper, characteristics of graphite oxidation corrosion during the air ingress accident can be reasonably captured, including distributions of graphite corrosion amount on the different cross-sections, time histories of local corrosion amount at the monitoring points and overall corrosion amount in the core, respectively. Based on the transient simulation results, the corrosion pattern and its corrosion rate would approach to the steady-state conditions as the accident continuously progresses. The total amount of graphite corrosion during a 3-day accident time is predicted to be about 31 kg with the predicted asymptotic corrosion rate. This predicted value is less than that from the previous work of Gao and Shi.

  19. Research process of nondestructive testing pitting corrosion in metal material

    Directory of Open Access Journals (Sweden)

    Bo ZHANG

    2017-12-01

    Full Text Available Pitting corrosion directly affects the usability and service life of metal material, so the effective nondestructive testing and evaluation on pitting corrosion is of great significance for fatigue life prediction because of data supporting. The features of pitting corrosion are elaborated, and the relation between the pitting corrosion parameters and fatigue performance is pointed out. Through introducing the fundamental principles of pitting corrosion including mainly magnetic flux leakage inspection, pulsed eddy current and guided waves, the research status of nondestructive testing technology for pitting corrosion is summarized, and the key steps of nondestructive testing technologies are compared and analyzed from the theoretical model, signal processing to industrial applications. Based on the analysis of the signal processing specificity of different nondestructive testing technologies in detecting pitting corrosion, the visualization combined with image processing and signal analysis are indicated as the critical problems of accurate extraction of pitting defect information and quantitative characterization for pitting corrosion. The study on non-contact nondestructive testing technologies is important for improving the detection precision and its application in industries.

  20. Parotid Duct Repair with Intubation Tube: Technical Note

    Science.gov (United States)

    Öztürk, Muhammed Beşir; Barutca, Seda Asrufoğlu; Keskin, Elif Seda; Atik, Bekir

    2017-01-01

    The parotid duct can be damaged in traumatic injuries and surgical interventions. Early diagnosis and treatment of a duct injury is of great importance because complications such as sialocele and salivary gland fistula may develop if the duct is not surgically repaired. We think the cuff of an intubation tube is an ideal material in parotid duct repair, because of its technical characteristics, easiness of availability, and low-cost. In this paper, we described the use of the cuff cannula of an intubation tube for the diagnosis and treatment of parotid duct laceration, as a low-cost and easy to access material readily available in every operating room. PMID:28713751

  1. Basic aspects of the carbon dioxide corrosion in oil and gas production; Aspectos basicos de la corrosion por dioxido de carbono en la produccion de petroleo y gas

    Energy Technology Data Exchange (ETDEWEB)

    Angulo Macias, J.

    2010-07-01

    Carbon dioxide (CO{sub 2}) is a non-corrosive gas within the driven conditions in the oil and gas industry, but the presence of water converts it, maybe, in the most important component in the corrosive processes in this industry. Corrosion has an important impact inside the oil and gas companies, no only in economics but also in safety, environmental and social aspects. After several decades of investigation of these corrosion processes, there are still several mechanisms not fully understood. (Author) 19 refs.

  2. Corrosion behavior of duplex and reference cladding in NPP Grohnde

    International Nuclear Information System (INIS)

    Besch, O.A.; Yagnik, S.K.; Eucken, C.M.; Bradley, E.R.

    1996-01-01

    The Nuclear Fuel Industry Research (NFIR) Group undertook a lead test assembly (LTA) program in NPP Grohnde PWR in Germany to assess the corrosion performance of duplex and reference cladding. Two identical 16 by 16 LTAs, each containing 32 peripheral test rods, completed four reactor cycles, reaching a peak rod burnup of 46 MWd/kgU. The results from poolside examinations performed at the end of each cycle, together with power histories and coolant chemistry, are reported. Five different cladding materials were characterized during fabrication. The corrosion performance of the cladding materials was tracked in long-term tests in high-pressure, high-temperature autoclaves. The relative ranking of corrosion behavior in such tests corresponded well with the in-reactor corrosion performance. The extent and distribution of hydriding in duplex and reference specimens during the autoclave testing has been characterized. The in-reactor corrosion data indicate that the low-tin Zircaloy-4 reference cladding, R2, had an improved corrosion resistance compared to high-tin Zircaloy-4 reference cladding, R1. Two types of duplex cladding, D1 (Zr-2.5% Nb) and D2 (Zr-0.4% Fe-0.5% Sn), showed an even further improvement in corrosion resistance compared to R2 cladding. The third duplex cladding, D3 (Zr-4 + 1.0% Nb), had significantly less corrosion resistance, which was inferior to R1. The in-reactor and out-reactor corrosion performances have been ranked

  3. A study on CT features of intrahepatic bile duct abscess

    International Nuclear Information System (INIS)

    Min Pengqiu; Li Peng; He Zhiyan; Chen Weixia; Liu Yan

    2001-01-01

    Objective: To evaluate CT features of intrahepatic bile duct abscess (IBDA) and its pathologic basis. Methods: The CT imaging data of 31 consecutive cases of intrahepatic bile duct abscess proved by surgery or clinical treatments from October 1989 to February 1999 were retrospectively studied. The causes included acute obstructive suppurative cholangitis and retrograde infection due to different etiologies. For all the cases, the CT manifestations of liver abscess, bile duct abnormalities, and their relationship were observed respectively. Results: Manifestations of liver abscess were revealed in all cases (31/31, 100%). The CT manifestations of bile duct abnormalities included signs of etiologies caused bile duct obstruction and other signs including cholangiectasis (29/31, 93.5%), the dilated bile ducts communicated with (5/31, 16.1%) or abut on (8/31, 25.8%) the abscesses, and gas collection in bile ducts (10/31, 32.2%). The signs showing the relationship between liver abscess and bile duct abnormalities were that the abscesses complied with the obstructive site and the dilated bile ducts (15/31, 48.4%), and the liver abscesses located in different (7/31, 22.6%) or same (4/31, 12.9%) liver lobes or segments with gas collection in the dilated bile ducts. Conclusion: The CT manifestations of IBDA included signs of liver abscess, abnormalities of bile ducts, and signs showing their relationship. CT scanning was helpful in making comprehensive and accurate diagnosis of IBDA

  4. Radiologic imaging of bile duct changes by clonorchiasis

    International Nuclear Information System (INIS)

    Kim, Myung Joon; Yoo, Hyung Sik; Lee, Jong Tae; Jung, Soon Hee

    1988-01-01

    The changes of the bile ducts were reviewed retrospectively in 38 patients of clonorchiasis by ultrasonography and/or CT. Diagnosis was made in 13 patients by cholecystectomy and exploration of the common bile duct, another 2 patients by segmentectomy and wedge resection of the liver, and 23 patients by stool examination. 14 of 36 cases done ultrasonography showed the parallel channel sign, and small nodular echoes around the dilated bile ducts. And 3 cases showed the echoes of worm of clonorchis sinensis in the common bile duct. 22 of 36 cases showed the parallel channel signs only. All cases (11) done CT showed diffuse dilatation of the peripheral bile ducts. 5 of 11 cases showed ring or tubular contrast enhancement around the dilated bile ducts. In 2 cases of liver resection, the bile ducts showed adenomatous hyperplasia and severe periductal fibrosis. Proliferation of blood vessels and infiltration of inflammatory cells were also seen. So we consider that the increased echoes of the bile duct wall, small nodular echoes around the bile ducts were attributed to the bile duct dilatation, severe adenomatous hyperplasia and periductal fibrosis. The ring or tubular contrast enhancement of the dilated bile ducts seems to be caused by the marked periductal inflammation resulting in capillary proliferation and the periductal fibrosis.

  5. Radiologic imaging of bile duct changes by clonorchiasis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Joon; Yoo, Hyung Sik; Lee, Jong Tae; Jung, Soon Hee [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1988-10-15

    The changes of the bile ducts were reviewed retrospectively in 38 patients of clonorchiasis by ultrasonography and/or CT. Diagnosis was made in 13 patients by cholecystectomy and exploration of the common bile duct, another 2 patients by segmentectomy and wedge resection of the liver, and 23 patients by stool examination. 14 of 36 cases done ultrasonography showed the parallel channel sign, and small nodular echoes around the dilated bile ducts. And 3 cases showed the echoes of worm of clonorchis sinensis in the common bile duct. 22 of 36 cases showed the parallel channel signs only. All cases (11) done CT showed diffuse dilatation of the peripheral bile ducts. 5 of 11 cases showed ring or tubular contrast enhancement around the dilated bile ducts. In 2 cases of liver resection, the bile ducts showed adenomatous hyperplasia and severe periductal fibrosis. Proliferation of blood vessels and infiltration of inflammatory cells were also seen. So we consider that the increased echoes of the bile duct wall, small nodular echoes around the bile ducts were attributed to the bile duct dilatation, severe adenomatous hyperplasia and periductal fibrosis. The ring or tubular contrast enhancement of the dilated bile ducts seems to be caused by the marked periductal inflammation resulting in capillary proliferation and the periductal fibrosis.

  6. Critical corrosion issues and mitigation strategies impacting the operability of LWR's

    International Nuclear Information System (INIS)

    Jones, R.L.

    1996-01-01

    Recent corrosion experience in US light water reactor nuclear power plants is reviewed with emphasis on mitigation strategies to control the cost of corrosion to LWR operators. Many components have suffered corrosion problems resulting in industry costs of billions of dollars. The most costly issues have been stress corrosion cracking of stainless steel coolant piping in boiling water reactors and corrosion damage to steam generator tubes in pressurized water reactors. Through industry wide R and D programs these problems are now understood and mitigation strategies have been developed to address the issues in a cost effective manner. Other significant corrosion problems for both reactor types are briefly reviewed. Tremendous progress has been made in controlling corrosion, however, minimizing its impact on plant operations will present a continuing challenge throughout the remaining service lives of these power plants

  7. A Case of Adenomyomatous Hyperplasia of the Extrahepatic Bile Duct

    Directory of Open Access Journals (Sweden)

    Masakatsu Numata

    2011-08-01

    Full Text Available Adenomyomatous hyperplasia is rarely found in the extrahepatic bile duct. A 54-year-old man was referred to our center with a diagnosis of extrahepatic bile duct stenosis which had been detected by endoscopic retrograde choloangiopancreatography. Abdominal computed tomography revealed thickening of the wall of the middle extrahepatic bile duct, however no malignant cells were detected by cytology. Since bile duct carcinoma could not be ruled out, we performed resection of the extrahepatic duct accompanied by lymph node dissection. Histopathologically, the lesion was diagnosed as adenomyomatous hyperplasia of the extrahepatic bile duct. Present and previously reported cases showed the difficulty of making a diagnosis of adenomyomatous hyperplasia of the extrahepatic bile duct preoperatively or intraoperatively. Therefore, when adenomyomatous hyperplasia is suspected, a radical surgical procedure according to malignant disease may be necessary for definitive diagnosis.

  8. Dispersion properties of ducted whistlers, generated by lightning discharge

    Directory of Open Access Journals (Sweden)

    D. L. Pasmanik

    2005-06-01

    Full Text Available Whistler-mode wave propagation in magnetospheric ducts of enhanced cold plasma density is studied. The case of the arbitrary ratio of the duct radius to the whistler wavelength is considered, where the ray-tracing method is not applicable. The set of duct eigenmodes and their spatial structure are analysed and dependencies of eigenmode propagation properties on the duct characteristics are studied. Special attention is paid to the analysis of the group delay time of one-hop propagation of the whistler wave packet along the duct. We found that, in contrast to the case of a wide duct, the group delay time in a rather narrow duct decreases as the eigenmode number increases. The results obtained are suggested for an explanation of some types of multi-component whistler signals.

  9. Spectral measurements of gamma radiation streaming through ducts

    International Nuclear Information System (INIS)

    Meenakshisundaram, P.K.; Bhatnagar, V.M.; Raghunath, V.M.; Gopinath, D.V.

    1979-01-01

    The paper presents the spectral measurements of gamma radiation streaming through multi-legged rectangular concrete ducts for cesium-137 and cobald-60 sources. Effect of lead lining the inner surface of the duct on the streaming radiation spectrum and optimization of liner thickness for minimum streaming radiation dose have been studied. For three-legged ducts, a comparative analysis of lead lining the entire duct as against lining any one or both the corners of the duct is reported. It is seen that lead lining any one of the corners would reduce the streaming radiation dose by a factor of 5 to 12. Lining both the corners which is nearly as effective as lining the entire duct reduces the dose by a factor of 16 to 60 depending on the soruce energy and duct dimensions. (orig.)

  10. XPS and Auger investigation of mechanisms affecting corrosion inhibition of metals

    International Nuclear Information System (INIS)

    Holmes, R.M.; Surman, D.J.

    1989-01-01

    Atmospheric corrosion of metal surfaces need not be extremely obvious to cause extensive damage to many products. Very small corrosion pits and spots can cause defects in critical copper sources, often resulting in the catastrophic failure of complete electronic assemblies. Microscopic corrosion in steel can lead to the complete failure of subsequently added coatings or furnishings, the automotive industry has become aware. In addition, corrosion at its earliest stages can initiate other corrosion at a later date, resulting in inferior finishings or coatings. A major interest in atmospheric corrosion is in the mechanism by which the initial corrosion initiated and propagated. The initial phase involves the attack of the very other surface layers, hence it is difficult to observe with conventional techniques such as SEM/EDX. This paper presents some of the results obtained by both Auger electron spectroscopy and x- ray photoelectron spectroscopy, of steel and copper samples exposed to corrosive materials under controlled conditions

  11. Evaluation of corrosion products formed by sulfidation as inhibitors of the naphthenic corrosion of AISI-316 steel

    Science.gov (United States)

    Sanabria-Cala, J. A.; Montañez, N. D.; Laverde Cataño, D.; Y Peña Ballesteros, D.; Mejía, C. A.

    2017-12-01

    Naphthenic acids present in oil from most regions worldwide currently stand as the main responsible for the naphthenic corrosion problems, affecting the oil-refining industry. The phenomenon of sulfidation, accompanying corrosion processes brought about by naphthenic acids in high-temperature refining plant applications, takes place when the combination of sulfidic acid (H2S) with Fe forms layers of iron sulphide (FeS) on the material surface, layers with the potential to protect the material from attack by other corrosive species like naphthenic acids. This work assessed corrosion products formed by sulfidation as inhibitors of naphthenic corrosion rate in AISI-316 steel exposed to processing conditions of simulated crude oil in a dynamic autoclave. Calculation of the sulfidation and naphthenic corrosion rates were determined by gravimetry. The surfaces of the AISI-316 gravimetric coupons exposed to acid systems; were characterized morphologically by X-Ray Diffraction (XRD) and X-ray Fluorescence by Energy Dispersive Spectroscopy (EDS) combined with Scanning Electron Microscopy (SEM). One of the results obtained was the determination of an inhibiting effect of corrosion products at 250 and 300°C, where lower corrosion rate levels were detected. For the temperature of 350°C, naphthenic corrosion rates increased due to deposition of naphthenic acids on the areas where corrosion products formed by sulfidation have lower homogeneity and stability on the surface, thus accelerating the destruction of AISI-316 steel. The above provides an initial contribution to oil industry in search of new alternatives to corrosion control by the attack of naphthenic acids, from the formation of FeS layers on exposed materials in the processing of heavy crude oils with high sulphur content.

  12. Environmental degradation of materials and corrosion control in metals

    International Nuclear Information System (INIS)

    Lou, J.; Elboujdaini, M.; Shoesmith, D.; Patnaik, P.C.

    2003-01-01

    The first International Symposium on Environmental Degradation of Materials and Corrosion Control In Metals (EDMCCM), held in Quebec City in 1999, was very successful. Encouraged by this success. the Metallurgical Society of CIM organized the Second International Conference in what is hoped will be an on-going series. This meeting was held in Vancouver, British Columbia, Canada, in August 2003. The objective of this conference was to provide a wide-ranging forum for the discussion of recent developments in the study and understanding of corrosion degradation of metals and alloys and the variety of processes by which corrosion damage accumulates. The scope of the meeting ranged from the fundamental to the very applied with a primary emphasis on the inter-relationships between chemical, electrochemical, mechanical and metallurgical features of corrosion. This symposium was an excellent forum for the exchange of ideas and approaches between generally disparate fields of endeavour. The success of the symposium can be gauged from the large number of papers presented and the outstanding level of international participation, with authors from China, Iran, Japan, North America, Russia, United Kingdom and Venezuela. In addition authors from six Canadian provinces (Alberta, British Columbia, New Brunswick, Ontario, Quebec, Saskatchewan) participated. Six keynote presentations covered a wide range of topics and industries in corrosion and corrosion control, and a total 45 papers were presented, spread over three days in six individual sessions; Electrochemistry and Corrosion of Metals, Corrosion and Cracking Behaviour. Hydrogen in Steel and Pipeline Corrosion, Corrosion Case Studies and Applications, Characterization of Corrosion Behaviour, and Corrosion Protection Coatings. (author)

  13. SNM holdup assessment of Los Alamos exhaust ducts

    International Nuclear Information System (INIS)

    Marshall, R.S.

    1994-02-01

    Fissile material holdup in glovebox and fume hood exhaust ducting has been quantified for all Los Alamos duct systems. Gamma-based, nondestructive measurements were used to quantify holdup. The measurements were performed during three measurement campaigns. The first campaign, Phase I, provided foot-by-foot, semiquantitative measurement data on all ducting. These data were used to identify ducting that required more accurate (quantitative) measurement. Of the 280 duct systems receiving Phase I measurements, 262 indicated less than 50 g of fissile holdup and 19 indicated fissile holdup of 50 or more grams. Seven duct systems were measured in a second campaign, called Series 1, Phase II. Holdup estimates on these ducts ranged from 421 g of 235 U in a duct servicing a shut-down uranium-machining facility to 39 g of 239 Pu in a duct servicing an active plutonium-processing facility. Measurements performed in the second campaign proved excessively laborious, so a third campaign was initiated that used more efficient instrumentation at some sacrifice in measurement quality. Holdup estimates for the 12 duct systems measured during this third campaign ranged from 70 g of 235 U in a duct servicing analytical laboratories to 1 g of 235 U and 1 g of 239 Pu in a duct carrying exhaust air to a remote filter building. These quantitative holdup estimates support the conclusion made at the completion of the Phase I measurements that only ducts servicing shut-down uranium operations contain about 400 g of fissile holdup. No ventilation ducts at Los Alamos contain sufficient fissile material holdup to present a criticality safety concern

  14. Corrosion evaluation technology

    International Nuclear Information System (INIS)

    Kim, Uh Chul; Han, Jeong Ho; Nho, Kye Ho; Lee, Eun Hee; Kim, Hong Pyo; Hwang, Seong Sik; Lee, Deok Hyun; Hur, Do Haeng; Kim, Kyung Mo.

    1997-09-01

    A multifrequency ACPD system was assembled which can measure very small crack. Stress corrosion cracking test system with SSRT operating high temperature was installed. Stress corrosion cracking test of newly developed alloy 600 and existing alloy 600 was carried out in steam atmosphere of 400 deg C. No crack was observed in both materials within a test period of 2,000 hrs. Corrosion fatigue test system operating at high temperature was installed in which fatigue crack was measured by CDPD. Lead enhanced the SCC of the Alloy 600 in high temperature water, had a tendency to modify a cracking morphology from intergranular to transgranular. Pit initiation preferentially occurred at Ti-rich carbide. Resistance to pit initiation decreased with increasing temperature up to 300 deg C. Test loop for erosion corrosion was designed and fabricated. Thin layer activation technique was very effective in measuring erosion corrosion. Erosion corrosion of a part of secondary side pipe was evaluated by the Check Family Codes of EPRI. Calculated values of pipe thickness by Check Family Codes coincided with the pipe thickness measured by UT with an error of ± 20%. Literature review on turbine failure showed that failure usually occurred in low pressure turbine rotor disc and causes of failure are stress corrosion cracking and corrosion fatigue. (author). 12 refs., 20 tabs., 77 figs

  15. Aluminum Corrosion and Turbidity

    International Nuclear Information System (INIS)

    Longtin, F.B.

    2003-01-01

    Aluminum corrosion and turbidity formation in reactors correlate with fuel sheath temperature. To further substantiate this correlation, discharged fuel elements from R-3, P-2 and K-2 cycles were examined for extent of corrosion and evidence of breaking off of the oxide film. This report discusses this study

  16. Demystifying Controlling Copper Corrosion

    Science.gov (United States)

    The LCR systematically misses the highest health and corrosion risk sites for copper. Additionally, there are growing concerns for WWTP copper in sludges and discharge levels. There are many corrosion control differences between copper and lead. This talk explains the sometimes c...

  17. Archaeological analogs and corrosion

    International Nuclear Information System (INIS)

    David, D.

    2008-01-01

    In the framework of the high level and long life radioactive wastes disposal deep underground, the ANDRA built a research program on the material corrosion. In particular they aim to design containers for a very long time storage. Laboratory experiments are in progress and can be completed by the analysis of metallic archaeological objects and their corrosion after hundred years. (A.L.B.)

  18. Erosion and erosion-corrosion

    International Nuclear Information System (INIS)

    Isomoto, Yoshinori

    2008-01-01

    It is very difficult to interpret the technical term of erosion-corrosion' which is sometimes encountered in piping systems of power plants, because of complicated mechanisms and several confusing definitions of erosion-corrosion phenomena. 'FAC (flow accelerated corrosion)' is recently introduced as wall thinning of materials in power plant systems, as a representative of 'erosion-corrosion'. FAC is, however, not necessarily well understood and compared with erosion-corrosion. This paper describes firstly the origin, definition and fundamental understandings of erosion and erosion-corrosion, in order to reconsider and reconfirm the phenomena of erosion, erosion-corrosion and FAC. Next, typical mapping of erosion, corrosion, erosion-corrosion and FAC are introduced in flow velocity and environmental corrosiveness axes. The concept of damage rate in erosion-corrosion is finally discussed, connecting dissolution rate, mass transfer of metal ions in a metal oxide film and film growth. (author)

  19. Exploratory shaft liner corrosion estimate

    International Nuclear Information System (INIS)

    Duncan, D.R.

    1985-10-01

    An estimate of expected corrosion degradation during the 100-year design life of the Exploratory Shaft (ES) is presented. The basis for the estimate is a brief literature survey of corrosion data, in addition to data taken by the Basalt Waste Isolation Project. The scope of the study is expected corrosion environment of the ES, the corrosion modes of general corrosion, pitting and crevice corrosion, dissimilar metal corrosion, and environmentally assisted cracking. The expected internal and external environment of the shaft liner is described in detail and estimated effects of each corrosion mode are given. The maximum amount of general corrosion degradation was estimated to be 70 mils at the exterior and 48 mils at the interior, at the shaft bottom. Corrosion at welds or mechanical joints could be significant, dependent on design. After a final determination of corrosion allowance has been established by the project it will be added to the design criteria. 10 refs., 6 figs., 5 tabs

  20. Vibrational response of a rectangular duct of finite length excited by a turbulent internal flow

    Science.gov (United States)

    David, Antoine; Hugues, Florian; Dauchez, Nicolas; Perrey-Debain, Emmanuel

    2018-05-01

    Gas transport ductwork in industrial plants or air conditioning networks can be subject to vibrations induced by the internal flow. Most studies in this matter have been carried out on circular ducts. This paper focuses specifically on the vibratory response of a rectangular duct of finite length excited by an internal turbulent flow. A semi-analytical model taking into account the modal response of the structure due to both aerodynamic and acoustic contributions is derived. The aerodynamic component of the excitation is applied on the basis of Corcos model where the power spectral density of the wall pressure is determined experimentally. The acoustic component is based on the propagating modes in the duct where the acoustic modal contribution are extracted via cross-spectral densities. The vibrational response is given for a 0.2 × 0.1 × 0.5 m3 duct made of 3 mm steel plates excited by 20 m/s or 30 m/s flows. Comparisons between experimental results and numerical predictions show a good agreement. The competition between acoustic and aerodynamic components is highlighted.

  1. Atmospheric corrosion of mild steel in Oman

    Energy Technology Data Exchange (ETDEWEB)

    Gismelseed, Abbasher, E-mail: abbasher@squ.edu.om; Al-Harthi, S. H.; Elzain, M.; Al-Rawas, A. D.; Yousif, A.; Al-Saadi, S.; Al-Omari, I.; Widatallah, H.; Bouziane, K. [College of Science, Department of Physics (Oman)

    2006-01-15

    A systematic study has been made of the initial corrosion products which form on mild steel capons exposed near the coastal region of Oman and at some industrial areas. The phases and compositions of the products formed at different periods of exposure were examined by using Moessbauer spectroscopy (295 and 78 K) and X-ray diffraction (XRD) techniques. The results show that lepidocorcite and maghemite are early corrosion products and goethite starts to form after 2 months of metal exposure to the atmosphere. Akaganeite is an early corrosion product but it forms in marine environments only, which reflects the role of chlorine effect in the atmosphere. The 12 months coupons showed the presence of goethite, lepidocorcite and maghemite, but no akaganeite being seen in the products of one of the studied areas.

  2. Atmospheric corrosion of mild steel in Oman

    International Nuclear Information System (INIS)

    Gismelseed, Abbasher; Al-Harthi, S. H.; Elzain, M.; Al-Rawas, A. D.; Yousif, A.; Al-Saadi, S.; Al-Omari, I.; Widatallah, H.; Bouziane, K.

    2006-01-01

    A systematic study has been made of the initial corrosion products which form on mild steel capons exposed near the coastal region of Oman and at some industrial areas. The phases and compositions of the products formed at different periods of exposure were examined by using Moessbauer spectroscopy (295 and 78 K) and X-ray diffraction (XRD) techniques. The results show that lepidocorcite and maghemite are early corrosion products and goethite starts to form after 2 months of metal exposure to the atmosphere. Akaganeite is an early corrosion product but it forms in marine environments only, which reflects the role of chlorine effect in the atmosphere. The 12 months coupons showed the presence of goethite, lepidocorcite and maghemite, but no akaganeite being seen in the products of one of the studied areas.

  3. Corrosion of aluminum components and remedial measures

    International Nuclear Information System (INIS)

    Sheikh, S.T.; Khalique, A.; Malik, F.A.

    2006-01-01

    Aluminum has versatile physical properties, mechanical strength, corrosion resistance, and is used in special applications like aerospace, automobiles and other strategic industries. The outdoor exposed structural components of aluminum have very good corrosion resistance due to the thick oxide layer (0.2 -0.4 micro). This study involves the corrosion of aluminum based components, though aluminum is protected by an oxide layer but due to extreme weather and environmental conditions the oxide layer was damaged. The corroded product was removed, pits or cavities formed due to the material removal were filled with epoxy resins and acrylic-based compounds containing fibreglass as reinforcement. Optimum results were obtained with epoxy resins incorporated with 5% glass fibers. The inner surface of the components was provided further protection with a cellulose nitrate compound. (author)

  4. Magnetohydrodynamic duct and channel flows at finite magnetic Reynolds numbers

    Energy Technology Data Exchange (ETDEWEB)

    Bandaru, Vinodh Kumar

    2015-11-27

    Magnetohydrodynamic duct flows have so far been studied only in the limit of negligible magnetic Reynolds numbers (R{sub m}). When R{sub m} is finite, the secondary magnetic field becomes significant, leading to a fully coupled evolution of the magnetic field and the conducting flow. Characterization of such flows is essential in understanding wall-bounded magnetohydrodynamic turbulence at finite R{sub m} as well as in industrial applications like the design of electromagnetic pumps and measurement of transient flows using techniques such as Lorentz force velocimetry. This thesis presents the development of a numerical framework for direct numerical simulations (DNS) of magnetohydrodynamic flows in straight rectangular ducts at finite R{sub m}, which is subsequently used to study three specific problems. The thesis opens with a brief overview of MHD and a review of the existing state of art in duct and channel MHD flows. This is followed by a description of the physical model governing the problem of MHD duct flow with insulating walls and streamwise periodicity. In the main part of the thesis, a hybrid finite difference-boundary element computational procedure is developed that is used to solve the magnetic induction equation with boundary conditions that satisfy interior-exterior matching of the magnetic field at the domain wall boundaries. The numerical procedure is implemented into a code and a detailed verification of the same is performed in the limit of low R{sub m} by comparing with the results obtained using a quasistatic approach that has no coupling with the exterior. Following this, the effect of R{sub m} on the transient response of Lorentz force is studied using the problem of a strongly accelerated solid conducting bar in the presence of an imposed localized magnetic field. The response time of Lorentz force depends linearly on R{sub m} and shows a good agreement with the existing experiments. For sufficiently large values of R{sub m}, the peak

  5. Acoustic Power Transmission Through a Ducted Fan

    Science.gov (United States)

    Envia, Ed

    2016-01-01

    For high-speed ducted fans, when the rotor flowfield is shock-free, the main contribution to the inlet radiated acoustic power comes from the portion of the rotor stator interaction sound field that is transmitted upstream through the rotor. As such, inclusion of the acoustic transmission is an essential ingredient in the prediction of the fan inlet noise when the fan tip relative speed is subsonic. This paper describes a linearized Euler based approach to computing the acoustic transmission of fan tones through the rotor. The approach is embodied in a code called LINFLUX was applied to a candidate subsonic fan called the Advanced Ducted Propulsor (ADP). The results from this study suggest that it is possible to make such prediction with sufficient fidelity to provide an indication of the acoustic transmission trends with the fan tip speed.

  6. Impact fracture behavior of HT9 duct

    International Nuclear Information System (INIS)

    Huang, F.H.; Gelles, D.S.

    1994-07-01

    Ferritic alloys are known to undergo a ductile-brittle transition as the test temperature is decreased. This inherent problem has limited their applications to reactor component materials subjected to low neutron exposures. However, the excellent resistance to void swelling exhibited by these alloys has led to choosing the materials as candidate materials for fast and fusion reactor applications. Despite the ductile-brittle transition problem, results show that the materials exhibit superior resistance to fracture under very high neutron fluences at irradiation temperatures above 380 degrees C. Impact testing on FFTF duct sections of HT9 indicates that HT9 ducts have adequate fracture toughness at much higher temperatures for handling operations at room temperature and refueling operations

  7. Mullerian Ducts Anomalies: A Simple View

    International Nuclear Information System (INIS)

    Diaz Diaz, Nelson Enrique; Riano Montanez, Yeyson Fabian; Baron Criollo, Jose alexander

    2008-01-01

    Mullerian ducts anomalies are a major cause of infertility in women of reproductive age. They have multifactorial etiology. The following article reviews the classification of the American Fertility Society, the most widely accepted at present to describe this set of pathologies. Also a schematic review of the embryology is done and are shown cases of MRI, modality of choice by image to characterize the findings in the majority of presentation forms of these entities

  8. T-method duct design. Part 3

    International Nuclear Information System (INIS)

    Tsal, R.J.; Behls, H.F.; Mangel, R.

    1990-01-01

    This paper introduces a new method for simulating HVAC duct systems, called T-method. The desirability of simulation appears in many HVAC problems, such as determining system operating efficiency, system retrofitting, nuclear plant normal/emergency conditions, fire/smoke control systems, fans operating in parallel, pressure balancing after system modification, and noise generated by dampers. T-method is capable of simulating these problems. This paper includes problem definition, a theoretical approach, calculation procedures, and many examples

  9. Pressure drop in T's in concentric ducts

    International Nuclear Information System (INIS)

    Shock, R.A.W.

    1983-02-01

    A set of experiments has been carried out to measure the pressure drop characteristics of single-phase flow in dividing and joining right-angled T's in a concentric ducting system. These have been compared with measured pressure drops in a simple round tube system. In most tests with the concentric system the number of velocity heads lost is either similar to, or more than, the value for the round tubes. (author)

  10. corrosion problems and their relationship with the environment in the Colombian productive system

    International Nuclear Information System (INIS)

    Arroyave P, Carlos E; Herrera B, Francisco J; Delgado L, Juan; Cuervo T, Joaquin

    1999-01-01

    As a part of a broad study on the corrosion problems in the Colombian industry, it was included an assessment of the effect of the main corrosive environments (atmosphere, soil, salad and drinking water, and chemicals), on materials stability. On the other hand, the impact of the corrosion processes on the environmental constituents (live species, atmosphere, soil, materials, and water) was also assessed. Main conclusions are: Atmosphere is the more extensively corrosive environment, and, all the environmental constituents are affected by corrosion without significant differences

  11. Hinkley Point A gas duct repairs

    International Nuclear Information System (INIS)

    Curtis, R.F.

    1996-01-01

    In 1990, routine visual inspection of the Hinckley Point A Reactor 1 pressure vessel gas outlet ducts showed failures in the welded stud bolts retaining the insulation edging strips. Since the ducts are accessible only from within the pressure vessel, a remote repair technique that could be deployed via the vessel stand pipe had to be found. A drawn arc stud welding and work package formerly used at the Oldbury Power Station was modified for the purpose. The only manipulators with sufficient reach and adequate carrying capacity to deploy the package were the Sizewell SNAKES manipulators. One of these was modified to fit the Hinckley reactor and repairs have been successfully carried out. Similar studs on the gas ducts in Reactor 2, are shielded from visual inspection by a Z-clip feature. A technique using pulsed thermography was developed. The studs were heated for a short time at their exposed ends using a prefocused lamp and the heat decay patterns monitored by an infrared camera enabling attached and detached studs to be distinguished. The inspection package was deployed using the SNAKES manipulator again. In both operations, I-Grip computer modelling was used in the design of the package envelope and the deployment routes. (UK)

  12. Dynamic response of cracked hexagonal subassembly ducts

    International Nuclear Information System (INIS)

    Glazik, J.L.; Petroski, H.J.

    1979-01-01

    The hexagonal subassembly ducts (hexcans) of current Liquid Metal Fast Breeder Reactor (LMFBR) designs are typically made of 20% coldworked Type 316 stainless steel. Prolonged exposure of this initially tough and ductile material to a fast neutron flux at high temperatures can result in severe embrittlement. Under these conditions, the unstable crack propagation of flaws, which may have been introduced during fabrication or transportation of the hexcans, is a problem of interest in LMFBR safety analysis. The abnormal overpressurization resulting from certain interactions within a subassembly, or the rupture of one or more fuel pins, may be sufficient to overload an otherwise subcritical crack in an embrittled hexcan. This paper examines the dynamic elastic response of flawed and unflawed fast reactor subassembly ducts. A plane-strain finite element analysis was performed for ducts containing internal corner cracks, as well as external midflat cracks. Two worst case loading situations were considered: rapid uniform internal pressurization and suddenly applied point loads at opposite midflats. The finite-element code CHILES, which can accomodate the stress singularities that occur at crack tips, was given dynamic capabilities through the inclusion of a consistent mass matrix and step-by-step time integration scheme. The SAP IV code was also employed for eigenvalue analysis and modal response. Although this code does not contain singular elements in its element library, dynamic stress intensity factors were calculated by a technique requiring only ordinary isoparametric quadrilaterals

  13. Guided wave testing for touch point corrosion

    International Nuclear Information System (INIS)

    Alleyne, David

    2012-01-01

    Guided wave testing (GWT) is established in the petrochemical and related industries, primarily for the detection of corrosion flaws. Touch point corrosion at support positions in pipe-work has become a significant problem within many operating gas, chemical and petro-chemical plants world-wide, particularly as a high proportion of these plants have been operational for many decades. This article demonstrates how GWT using guided waves sent axially along the pipe can be performed for the detection and accurate classification of touchpoint corrosion. The major advantage of GWT methods for the detection of touch point corrosion is its ability to examine several support positions from a single easy to access transducer position. The strategy is then to prioritize or rank the condition of the pipe at the supports by removing those with negligible wall loss from scheduling for further inspection. Guided waves are accurate at detecting and classifying corrosion patches at support positions, but deep pits within such patches are more difficult to accurately identify. Examples using data from routine inspection testing are used to support the development of the methods and testing approaches presented. Recent developments of the interpretation methods, testing procedures and calibration methods have significantly enhanced the capabilities of GWT for this important application.

  14. Remote measurement of corrosion using ultrasonic techniques

    International Nuclear Information System (INIS)

    Garcia, K.M.; Porter, A.M.

    1995-02-01

    Supercritical water oxidation (SCWO) technology has the potential of meeting the US Department of Energy's treatment requirements for mixed radioactive waste. A major technical constraint of the SCWO process is corrosion. Safe operation of a pilot plant requires monitoring of the corrosion rate of the materials of construction. A method is needed for measurement of the corrosion rate taking place during operation. One approach is to directly measure the change in wall thickness or growth of oxide layer at critical points in the SCWO process. In FY-93, a brief survey of the industry was performed to evaluate nondestructive evaluation (NDE) methods for remote corrosion monitoring in supercritical vessels. As a result of this survey, it was determined that ultrasonic testing (UT) methods would be the most cost-effective and suitable method of achieving this. Therefore, the objective for FY-94 was to prove the feasibility of using UT to monitor corrosion of supercritical vessels remotely during operation without removal of the insulation

  15. Effect of duct geometry on Wells turbine performance

    International Nuclear Information System (INIS)

    Shaaban, S.; Abdel Hafiz, A.

    2012-01-01

    Highlights: ► A Wells turbine duct design in the form of venturi duct is proposed and investigated. ► Optimum duct geometry is identified. ► Up to 14% increase of the turbine power can be achieved using the optimized duct geometry. ► Up to 9% improve of the turbine efficiency is attained by optimizing the turbine duct geometry. ► The optimized duct geometry results in tangible delay of the turbine stalling point. - Abstract: Wells turbines can represent important source of renewable energy for many countries. An essential disadvantage of Wells turbines is their low aerodynamic efficiency and consequently low power produced. In order to enhance the Wells turbine performance, the present research work proposes the use of a symmetrical duct in the form of a venturi tube with turbine rotor located at throat. The effects of duct area ratio and duct angle are investigated in order to optimize Wells turbine performance. The turbine performance is numerically investigated by solving the steady 3D incompressible Reynolds Averaged Navier–Stocks equation (RANS). A substantial improve of the turbine performance is achieved by optimizing the duct geometry. Increasing both the duct area ratio and duct angle increase the acceleration and deceleration upstream and downstream the rotor respectively. The accelerating flow with thinner boundary layer thickness upstream the rotor reduces the flow separation on the rotor suction side. The downstream diffuser reduces the interaction between tip leakage flow and blade suction side. Up to 14% increase in turbine power and 9% increase in turbine efficiency are achieved by optimizing the duct geometry. On other hand, a tangible delay of the turbine stall point is also detected.

  16. Imaging manifestation of hepatocellular carcinoma with bile duct tumor thrombi

    International Nuclear Information System (INIS)

    Liu Qingyu; Chen Jianyu; Liang Biling; Hu Tao

    2008-01-01

    Objective: To analyze the imaging features of hepatocellular carcinoma(HCC) with bile duct tumor thrombi. Methods: Thirteen patients with bile duct tumor thrombi proved pathologically underwent imaging examination. MR and CT were performed in 3 cases, and 2 cases had CT only and 8 cases had MRI only. Ultrasonography(US) was performed in all 13 patients. The accuracy of bile duct tumor thrombi detection was compared between US, CT and MRI with Fisher test. Results: Liver tumors and bile duct tumor thrombi were demonstrated in all patients on CT or MRI. Presence of intraluminal soft tissue mass was found in four of five cases on CT, and mild enhancement of the intraluminal mass in the arterial phase was noted, dilated bile duct distal to tumor thrombi was detected in all five patients. Eleven Tumor thrombi showed slight low signal intensity on T 1 WI, slight high signal intensity on T 2 WI, and mild to moderate contrast enhancement on the contrast-enhanced MR images. The MRCP findings of tumor thrombi were as follows: interruption, stricture of the bile ducts or irregular filling defect in the bile ducts with dilated intrahepatic ducts, bile duet was abruptly interrupted or showed a 'rat-tail' stricture (n=5); the common bile duct was filled with tumor thrombi, intrahepatic bile duct dilatation and missing common bile duct was noted on MRCP (n=2). Bile duct tumor thrombi were correctly diagnosed in 7 cases on US, and 12 cases on CT or MRI. Six cases were misdiagnosed or miss-diagnosed on US, and 4 cases were misdiagnosed on CT or MRI. There was no significant difference between US and CT/MRI in diagnosis of bile duct tumor thrombi (P=0.270). Conclusion: CT or MR imaging is useful for the diagnosis of HCC with biliary tumor thrombi and for evaluating the extension of thrombi. (authors)

  17. Unilateral Duplication Of Parotid Duct. A Rare Anatomical Variation

    Directory of Open Access Journals (Sweden)

    Humberto Ferreira Arquez

    2017-11-01

    Full Text Available Background: The paired parotid glands are the largest of the major salivary glands and produces mainly serous secretions. The secretion of this gland reaches the oral cavity through single parotid duct (Stensen’s duct. The parotid duct begins at the anterior border of the gland, crosses the masseter muscle, and then pierces the buccinator muscle to reach the mucosa lining the mouth at the level of the cheek. The purpose of this study is determine the morphologic features of the parotid duct and describe an anatomical variation until now unreported. Methods and Findings: A total of 17 cadavers were used for this study in the Morphology Laboratory at the University of Pamplona. In a cadaver were findings: The main parotid duct originated two conducts: Left superior parotid duct and Left inferior parotid duct, is observed the criss-cross of the ducts, and then perforated the buccinator muscle and entered the oral cavity at a double parotid papilla containing a double opening, separated from each other in 0,98 mm. In the remaining  33 parotid regions (97.06% the parotid duct is conformed to the classical descriptions given in anatomical textbooks. Conclusions: The parotid duct anatomy is important for duct endoscopy, lithotripsy, sialography and trans-ductal facial nerve stimulation in the early stage of facial palsy in some cases. The anatomical variations also has clinical importance for parotid gland surgery and facial cosmetic surgery. To keep in mind the parotid duct variation will reduce iatrogenic injury risks and improve diagnosis of parotid duct injury.

  18. Monitoring and modeling stress corrosion and corrosion fatigue damage in nuclear reactors

    International Nuclear Information System (INIS)

    Andresen, P.L.; Ford, F.P.; Solomon, H.D.; Taylor, D.F.

    1990-01-01

    Stress corrosion and corrosion fatigue are significant problems in many industries, causing economic penalties from decreased plant availability and component repair or replacement. In nuclear power reactors, environmental cracking occurs in a wide variety of components, including reactor piping and steam generator tubing, bolting materials and pressure vessels. Life assessment for these components is complicated by the belief that cracking is quite irreproducible. Indeed, for conditions which were once viewed as nominally similar, orders of magnitude variability in crack growth rates are observed for stress corrosion and corrosion fatigue of stainless steels and low-alloy steels in 288 degrees C water. This paper shows that design and life prediction approaches are destined to be overly conservative or to risk environmental failure if life is predicted by quantifying only the effects of mechanical parameters and/or simply ignoring or aggregating environmental and material variabilities. Examples include the Nuclear Regulatory Commission (NRC) disposition line for stress-corrosion cracking of stainless steel in boiling water reactor (BWR) water and the American Society of Mechanical Engineers' Section XI lines for corrosion fatigue

  19. Automated Methods Of Corrosion Measurements

    DEFF Research Database (Denmark)

    Bech-Nielsen, Gregers; Andersen, Jens Enevold Thaulov; Reeve, John Ch

    1997-01-01

    The chapter describes the following automated measurements: Corrosion Measurements by Titration, Imaging Corrosion by Scanning Probe Microscopy, Critical Pitting Temperature and Application of the Electrochemical Hydrogen Permeation Cell.......The chapter describes the following automated measurements: Corrosion Measurements by Titration, Imaging Corrosion by Scanning Probe Microscopy, Critical Pitting Temperature and Application of the Electrochemical Hydrogen Permeation Cell....

  20. Replacement of corrosion protection chromate primers and paints used in cryogenic applications on the Space Shuttle with wire arc sprayed aluminum coatings

    Science.gov (United States)

    Daniel, R. L.; Sanders, H. L.; Zimmerman, F. R.

    1995-01-01

    With the advent of new environmental laws restricting volatile organic compounds and hexavalent chrome emissions, 'environmentally safe' thermal spray coatings are being developed to replace the traditional corrosion protection chromate primers. A wire arc sprayed aluminum coating is being developed for corrosion protection of low pressure liquid hydrogen carrying ducts on the Space Shuttle Main Engine. Currently, this hardware utilizes a chromate primer to provide protection against corrosion pitting and stress corrosion cracking induced by the cryogenic operating environment. The wire are sprayed aluminum coating has been found to have good potential to provide corrosion protection for flight hardware in cryogenic applications. The coating development, adhesion test, corrosion test and cryogenic flexibility test results will be presented.

  1. Idiopathic chylopericardium treated by percutaneous thoracic duct embolization after failed surgical thoracic duct ligation

    Energy Technology Data Exchange (ETDEWEB)

    Courtney, Malachi; Ayyagari, Raj R. [Yale School of Medicine, Yale New Haven Hospital, New Haven, CT (United States); Division of Interventional Radiology, Department of Radiology, 789 Howard Avenue, P.O. Box 208042, New Haven, CT (United States)

    2015-06-15

    Chylopericardium rarely occurs in pediatric patients, but when it does it is most often a result of lymphatic injury during cardiothoracic surgery. Primary idiopathic chylopericardium is especially rare, with few cases in the pediatric literature. We report a 10-year-old boy who presented with primary idiopathic chylopericardium after unsuccessful initial treatment with surgical lymphatic ligation and creation of a pericardial window. Following readmission to the hospital for a right-side chylothorax resulting from the effluent from the pericardial window, he had successful treatment by interventional radiology with percutaneous thoracic duct embolization. This case illustrates the utility of thoracic duct embolization as a less-invasive alternative to surgical thoracic duct ligation, or as a salvage procedure when surgical ligation fails. (orig.)

  2. Idiopathic chylopericardium treated by percutaneous thoracic duct embolization after failed surgical thoracic duct ligation

    International Nuclear Information System (INIS)

    Courtney, Malachi; Ayyagari, Raj R.

    2015-01-01

    Chylopericardium rarely occurs in pediatric patients, but when it does it is most often a result of lymphatic injury during cardiothoracic surgery. Primary idiopathic chylopericardium is especially rare, with few cases in the pediatric literature. We report a 10-year-old boy who presented with primary idiopathic chylopericardium after unsuccessful initial treatment with surgical lymphatic ligation and creation of a pericardial window. Following readmission to the hospital for a right-side chylothorax resulting from the effluent from the pericardial window, he had successful treatment by interventional radiology with percutaneous thoracic duct embolization. This case illustrates the utility of thoracic duct embolization as a less-invasive alternative to surgical thoracic duct ligation, or as a salvage procedure when surgical ligation fails. (orig.)

  3. 16 CFR 23.10 - Misuse of “corrosion proof,” “noncorrosive,” “corrosion resistant,” “rust proof,” “rust resistant...

    Science.gov (United States)

    2010-01-01

    ... INDUSTRIES § 23.10 Misuse of “corrosion proof,” “noncorrosive,” “corrosion resistant,” “rust proof,” “rust resistant,” etc. (a) It is unfair or deceptive to: (1) Use the terms “corrosion proof,” “noncorrosive... the product will be immune from rust and other forms of corrosion during the life expectancy of the...

  4. Contribution to the study of the electrochemical behaviour of titanium and of its industrial shores in sulphuric environment. Characteristics of their resistance to pitting corrosion in neutral and acid halogenous environment

    International Nuclear Information System (INIS)

    Petit, Jacques-Alain

    1975-01-01

    After a presentation of the general metallurgical, physical, and corrosion resistance characteristics of titanium and of its alloys, this research thesis presents the experimental means, discusses the influence of experimental conditions on the assessment of the electrochemical behaviour of titanium and of its alloys. It reports an investigation of the cathodic behaviour of non-alloyed titanium and notably the hydrogen release kinetics in a concentrated acid environment. It discusses the influence of alloy composition on their cathodic behaviour, addresses the anodic behaviour of titanium and of its alloys in sulphuric environment, and the pitting corrosion of titanium and of its alloys in an acid and neutral halogenous environment [fr

  5. Stress-Assisted Corrosion in Boiler Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Preet M Singh; Steven J Pawel

    2006-05-27

    A number of industrial boilers, including in the pulp and paper industry, needed to replace their lower furnace tubes or decommission many recovery boilers due to stress-assisted corrosion (SAC) on the waterside of boiler tubes. More than half of the power and recovery boilers that have been inspected reveal SAC damage, which portends significant energy and economic impacts. The goal of this project was to clarify the mechanism of stress-assisted corrosion (SAC) of boiler tubes for the purpose of determining key parameters in its mitigation and control. To accomplish this in-situ strain measurements on boiler tubes were made. Boiler water environment was simulated in the laboratory and effects of water chemistry on SAC initiation and growth were evaluated in terms of industrial operations. Results from this project have shown that the dissolved oxygen is single most important factor in SAC initiation on carbon steel samples. Control of dissolved oxygen can be used to mitigate SAC in industrial boilers. Results have also shown that sharp corrosion fatigue and bulbous SAC cracks have similar mechanism but the morphology is different due to availability of oxygen during boiler shutdown conditions. Results are described in the final technical report.

  6. Corrosion of reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1963-01-15

    Much operational experience and many experimental results have accumulated in recent years regarding corrosion of reactor materials, particularly since the 1958 Geneva Conference on the Peaceful Uses of Atomic Energy, where these problems were also discussed. It was, felt that a survey and critical appraisal of the results obtained during this period had become necessary and, in response to this need, IAEA organized a Conference on the Corrosion of Reactor Materials at Salzburg, Austria (4-9 June 1962). It covered many of the theoretical, experimental and engineering problems relating to the corrosion phenomena which occur in nuclear reactors as well as in the adjacent circuits

  7. Eversion Bile Duct Anastomosis: A Safe Alternative for Bile Duct Size Discrepancy in Deceased Donor Liver Transplantation.

    Science.gov (United States)

    Leal-Leyte, Pilar; McKenna, Greg J; Ruiz, Richard M; Anthony, Tiffany L; Saracino, Giovanna; Giuliano, Testa; Klintmalm, Goran B; Kim, Peter Tw

    2018-04-10

    Introduction Bile duct size discrepancy in liver transplantation may increase the risk of biliary complications. The aim of this study was to evaluate the safety and outcomes of the eversion bile duct anastomosis technique in deceased donor liver transplantation (DDLT) with duct to duct anastomosis. Methods A total of 210 patients who received a DDLT with duct to duct anastomosis from 2012 to 2017 were divided into two groups: those who had eversion bile duct anastomosis (N=70) and standard bile duct anastomosis (N=140). Biliary complications rates were compared between the two groups. Results There was no difference in the cumulative incidence of biliary strictures (P=0.20) and leaks (P=0.17) between the two groups. The biliary complication rate in the eversion group was 14.3% and 11.4% in the standard anastomosis group. All the biliary complications in the eversion group were managed with endoscopic stenting. A severe size mismatch (≥3:1 ratio) was associated with a significantly higher incidence of biliary strictures (44.4%) compared to 2:1 ratio (8.2%), (P=0.002). Conclusion The use of the eversion technique is a safe alternative for bile duct discrepancy in deceased donor liver transplantation; however, severe bile duct size mismatch may be a risk factor for biliary strictures with such technique. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.

  8. Waterside corrosion of zirconium alloys in nuclear power plants

    International Nuclear Information System (INIS)

    1998-01-01

    Technically the study of corrosion of zirconium alloys in nuclear power reactors is a very active field and both experimental work and understanding of the mechanisms involved are going through rapid changes. As a result, the lifetime of any publication in this area is short. Because of this it has been decided to revise IAEA-TECDOC-684 - Corrosion of Zirconium Alloys in Nuclear Power Plants - published in 1993. This updated, revised and enlarged version includes major changes to incorporate some of the comments received about the first version. Since this review deals exclusively with the corrosion of zirconium and zirconium based alloys in water, and another separate publication is planned to deal with the fuel-side corrosion of zirconium based fuel cladding alloys, i.e. stress corrosion cracking, it was decided to change the original title to Waterside Corrosion of Zirconium Alloys in Nuclear Power Plants. The rapid changes in the field have again necessitated a cut-off date for incorporating new data. This edition incorporates data up to the end of 1995; including results presented at the 11 International Symposium on Zirconium in the Nuclear Industry held in Garmisch-Partenkirchen, Germany, in September 1995. The revised format of the review now includes: Introductory chapters on basic zirconium metallurgy and oxidation theory; A revised chapter discussing the present extent of our knowledge of the corrosion mechanism based on laboratory experiments; a separate and revised chapter discussing hydrogen uptake; a completely reorganized chapter summarizing the phenomenological observations of zirconium alloy corrosion in reactors; a new chapter on modelling in-reactor corrosion; a revised chapter devoted exclusively to the manner in which irradiation might influence the corrosion process; finally, a summary of our present understanding of the corrosion mechanisms operating in reactor

  9. Experiments and models of general corrosion and flow-assisted corrosion of materials in nuclear reactor environments

    Science.gov (United States)

    Cook, William Gordon

    Corrosion and material degradation issues are of concern to all industries. However, the nuclear power industry must conform to more stringent construction, fabrication and operational guidelines due to the perceived additional risk of operating with radioactive components. Thus corrosion and material integrity are of considerable concern for the operators of nuclear power plants and the bodies that govern their operations. In order to keep corrosion low and maintain adequate material integrity, knowledge of the processes that govern the material's breakdown and failure in a given environment are essential. The work presented here details the current understanding of the general corrosion of stainless steel and carbon steel in nuclear reactor primary heat transport systems (PHTS) and examines the mechanisms and possible mitigation techniques for flow-assisted corrosion (FAC) in CANDU outlet feeder pipes. Mechanistic models have been developed based on first principles and a 'solution-pores' mechanism of metal corrosion. The models predict corrosion rates and material transport in the PHTS of a pressurized water reactor (PWR) and the influence of electrochemistry on the corrosion and flow-assisted corrosion of carbon steel in the CANDU outlet feeders. In-situ probes, based on an electrical resistance technique, were developed to measure the real-time corrosion rate of reactor materials in high-temperature water. The probes were used to evaluate the effects of coolant pH and flow on FAC of carbon steel as well as demonstrate of the use of titanium dioxide as a coolant additive to mitigated FAC in CANDU outlet feeder pipes.

  10. Corrosion performance of atmospheric plasma sprayed alumina coatings on AZ31B magnesium alloy under immersion environment

    OpenAIRE

    D. Thirumalaikumarasamy; K. Shanmugam; V. Balasubramanian

    2014-01-01

    Plasma sprayed ceramic coatings are successfully used in many industrial applications, where high wear and corrosion resistance with thermal insulation are required. The alumina powders were plasma sprayed on AZ31B magnesium alloy with three different plasma spraying parameters. In the present work, the influence of plasma spray parameters on the corrosion behavior of the coatings was investigated. The corrosion behavior of the coated samples was evaluated by immersion corrosion test in 3.5 w...

  11. Modelling reinforcement corrosion in concrete

    DEFF Research Database (Denmark)

    Michel, Alexander; Geiker, Mette Rica; Stang, Henrik

    2012-01-01

    A physio-chemical model for the simulation of reinforcement corrosion in concrete struc-tures was developed. The model allows for simulation of initiation and subsequent propaga-tion of reinforcement corrosion. Corrosion is assumed to be initiated once a defined critical chloride threshold......, a numerical example is pre-sented, that illustrates the formation of corrosion cells as well as propagation of corrosion in a reinforced concrete structure....

  12. Corrosion of PWR steam generators

    International Nuclear Information System (INIS)

    Garnsey, R.

    1979-01-01

    Some designs of pressurized water reactor (PWR) steam generators have experienced a variety of corrosion problems which include stress corrosion cracking, tube thinning, pitting, fatigue, erosion-corrosion and support plate corrosion resulting in 'denting'. Large international research programmes have been mounted to investigate the phenomena. The operational experience is reviewed and mechanisms which have been proposed to explain the corrosion damage are presented. The implications for design development and for boiler and feedwater control are discussed. (author)

  13. Influence of Heat Treatments on the Corrosion Resistance of Medium -Carbon Steel using Sulfuric Spring Water

    Directory of Open Access Journals (Sweden)

    Ikhlas Basheer

    2015-02-01

    Full Text Available The corrosion is one of the important problems that may be occur to the parts of machinery and equipment after manufactured and when used as a result of exposure to corrosive media. Plain-carbon steel is considered as one of the most common minerals used in industrial applications. Some of heat treatments can have direct effect on the corrosion rate of steel by building up galvanic corrosion cells between its microscopic phases. Therefore, to adopt one of kinds of the plain-carbon steel and the most commonly used in industry to be study subject, that is medium carbon steel and took samples of this steel has been treated thermally in three methods which the normalising, annealing, and hardening .The corrosive media used in the research is Sulfuric Spring, it contains many chemical compounds to show its influence on the corrosion of steel. The weight loss method is used to determine corrosion rate and to compare between the results obtained, show that the greatest corrosion resistance of the annealed steel and the corrosion resistance of the hardened steel is the lowest while the corrosion  resistance of the normalised steel is in-between them.         Calcium carbonate was formed on the metal surface which acts as an isolating layer which decrease corrosion rate with time

  14. Corrosion degradation of materials in nuclear reactors and its control

    International Nuclear Information System (INIS)

    Kain, Vivekanand

    2016-01-01

    As in every industry, nuclear industry also faces the challenge of corrosion degradation due to the exposure of the materials to the working environment. The aggressiveness of the environment is enhanced by the presence of radiation and high temperature and high-pressure environment. Radiation has influence on both the materials (changes in microstructure and microchemistry) and the aqueous environment (radiolysis producing oxidizing conditions). A survey of all the light water reactors in the world showed that stress corrosion cracking (SCC) and flow accelerated corrosion (FAC) account for more than two third of all the corrosion degradation cases. This paper visits these two forms of corrosion in nuclear power plants and illustrates cases from Indian nuclear power plants. Remedial measures against these two forms of corrosion that are possible to be employed and the actual measures employed in Indian nuclear power plants are discussed. Key features of SCC in different types of nuclear power plants are discussed. Main reasons for irradiation assisted stress corrosion cracking (IASCC) are presented and discussed. The signature patterns of single and dual phase FAC captured from components replaced from Indian nuclear power plants are presented. The development of a correlation between the scallop size and rate of single phase FAC - based on the database developed in Indian nuclear power plants is presented. Based on these two forms of degradation in nuclear reactors, design of materials that would resist these forms of degradation is presented. (author)

  15. Predominant MIC Mechanisms in the Oil and Gas Industry

    Science.gov (United States)

    literature, terms such as microbial corrosion, biocorrosion, microbially influenced/induced corrosion, and biodegradation are often applied. All descriptions...express that microorganisms (bacteria, archaea, and fungi) influence the corrosion process of a given material. In this chapter, an overview of the common MIC mechanisms encountered in the oil and gas industry is presented.

  16. Pressure analysis in ventilation ducts at bituminization facility

    International Nuclear Information System (INIS)

    Kikuchi, Naoki; Iimura, Masato; Takahashi, Yuki; Omori, Eiichi; Yamanouchi, Takamichi

    1997-09-01

    Pressure analysis in cell ventilation ducts at bituminization facility where the fire and explosion accident occured was carried out. This report also describes the results of bench mark calculations for computer code EVENT84 which was used for the accident analysis. The bench mark calculations were performed by comparing the analytical results by EVENT84 code with the experimental data of safety demonstration tests of ventilation system which were carried out by JAERI. We confirmed the applicability of EVENT84 code with the conservative results. The pressure analysis in cell ventilation ducts at bituminization facility were performed by comparing the analytical results of duct pressure by EVENT84 code with the yield stress of destroyed ducts by explosion, in order to estimate the scale of explosion. As a result, we could not explain the damage of ducts quantitatively, but we found the local pressure peaks analytically in downstream ducts where the serious damages were observed. (author)

  17. Modelling hydrodynamic parameters to predict flow assisted corrosion

    International Nuclear Information System (INIS)

    Poulson, B.; Greenwell, B.; Chexal, B.; Horowitz, J.

    1992-01-01

    During the past 15 years, flow assisted corrosion has been a worldwide problem in the power generating industry. The phenomena is complex and depends on environment, material composition, and hydrodynamic factors. Recently, modeling of flow assisted corrosion has become a subject of great importance. A key part of this effort is modeling the hydrodynamic aspects of this issue. This paper examines which hydrodynamic parameter should be used to correlate the occurrence and rate of flow assisted corrosion with physically meaningful parameters, discusses ways of measuring the relevant hydrodynamic parameter, and describes how the hydrodynamic data is incorporated into the predictive model

  18. Electrochemical tests for pitting and crevice corrosion susceptibility

    International Nuclear Information System (INIS)

    Postlethwaite, J.

    1983-01-01

    Passive metals are being considered as container materials for the disposal of nuclear waste by deep burial. Localized corrosion is a potential problem and electrochemical techniques have an important role in the assessment of the susceptibility of these container materials to crevice and pitting corrosion. This paper critically reviews both the theoretical background and the experimental details of the electrochemical test methods presently used in both industrial and scientific studies of localized corrosion in both halide and non-halide solutions and identifies those areas where theory and experimental behaviour are in agreement and those areas for which there is neither well established theory nor an experimental test method

  19. Development of Novel Corrosion Techniques for a Green Environment

    OpenAIRE

    Ahmad, Zaki; Patel, Faheemuddin

    2012-01-01

    The synergistic effect of air pollution, brown clouds and greenhouse gasses is deleterious to human health and industrial products. The use of toxic inhibitors, chemicals in water treatment plants, and anti-fouling agents in desalination plants has contributed to the greenhouse effect. Conventional anti-corrosion techniques such as paints, coatings, inhibitor treatments, and cathodic protection paid no regard to greenhouse effect. Work on eco-friendly anti-corrosion techniques is scanty and l...

  20. Corrosion of Galvanized Steel Under Different Soil Moisture Contents

    OpenAIRE

    Pereira,Roseana Florentino da Costa; Oliveira,Edkarlla Sousa Dantas de; Lima,Maria Alice Gomes de Andrade; Brasil,Simone Louise Delarue Cezar

    2015-01-01

    Galvanized steel has been widely applied in different applications and the industry significantly increased its production in recent years. Some galvanized structures can be completely or partially buried, such as transmission tower footings. The corrosion of these metallic structures is related to the soil chemical and physicochemical properties, which define the aggressiveness of the environment. To assess the effect of the soil moisture on galvanized steel corrosion, a comparative study wa...

  1. Corrosion Control 101: A Journey in Rediscovery | Science ...

    Science.gov (United States)

    The presentation covers the general water chemistry of lead and copper, how contamination originates from home plumbing systems, what treatments are appropriate for controlling lead and copper to meet the Lead and Copper Rule, and what water quality and treatment factors directly impact the success and failure of corrosion control treatment. This talk re-introduces the overriding principles of corrosion control treatment to a water industry audience

  2. Problems raised by corrosion in the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Tricot, R.; Boutonnet, G.; Perrot, M.; Blum, J.-M.

    1977-01-01

    In the uranium ore processing industry, materials which resist both mechanical abrasion and corrosion in an acid medium are required. Different typical cases are examined. For the reprocessing of irradiated fuels, two processes are possible: the conventional wet process, of the Purex type, and the fluoride volatilization process. In the latter case, the problems raised by fluoride corrosion in the presence of fission products is examined. The other parts of the fuel cycle are examined in the same manner [fr

  3. Long-term atmospheric corrosion of mild steel

    International Nuclear Information System (INIS)

    Fuente, D. de la; Diaz, I.; Simancas, J.; Chico, B.; Morcillo, M.

    2011-01-01

    Research highlights: → Atmospheric corrosion rate stabilises after the first 4-6 years of exposure. → Great compaction of the rust layers in rural and urban atmospheres. → Corrosion (in rural and urban) deviates from common behaviour of bilogarithmic law. → Typical structures of lepidocrocite, goethite and akaganeite are identified. → Formation of hematite (industrial atmosphere) and ferrihydrite (marine atmosphere). - Abstract: A great deal of information is available on the atmospheric corrosion of mild steel in the short, mid and even long term, but studies of the structure and morphology of corrosion layers are less abundant and generally deal with those formed in just a few years. The present study assesses the structure and morphology of corrosion product layers formed on mild steel after 13 years of exposure in five Spanish atmospheres of different types: rural, urban, industrial and marine (mild and severe). The corrosion layers have been characterised by X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Long-term corrosion is seen to be more severe in the industrial and marine atmospheres, and less so in the rural and urban atmospheres. In all cases the corrosion rate is seen to decrease with exposure time, stabilising after the first 4-6 years of exposure. The most relevant aspects to be noted are (a) the great compaction of the rust layers formed in the rural and urban atmospheres, (b) the formation of hematite and ferrihydrite phases (not commonly found) in the industrial and marine atmospheres, respectively and (c) identification of the typical morphological structures of lepidocrocite (sandy crystals and flowery plates), goethite (cotton balls structures) and akaganeite (cotton balls structures and cigar-shaped crystals).

  4. Protection against deposits and corrosion in water systems

    Energy Technology Data Exchange (ETDEWEB)

    Lehmkuhl, J

    1978-11-01

    Industry generally, including mining and coal preparation, are in the habit of using large amounts of untreated service water. The service water can be softened or treated with hardness stabilisers in order to prevent deposit formation and corrosion. As often as not, deposits of dirt and attack by microorganisma also have to be eliminated. The article puts forward some suggestions for practical assistance in protecting water systems against the dangers of deposits and corrosion.

  5. HVAC; Heating, Ventilation, Air Conditioning - Aerosol Duct Sealant

    Science.gov (United States)

    2016-09-01

    material was applied. Annual energy and cost savings were predicted based on a typical weather year for each site. The installation of the duct...Balance reports; Visible dust streaks on duct work, ceilings near supply diffusers, or electrical boxes; Comfort complaints Specific Leakage...energy consumption , depending on the HVAC system type and the location of the ducts that were sealed. The cost effectiveness of the technology is

  6. Active noise control in a duct to cancel broadband noise

    Science.gov (United States)

    Chen, Kuan-Chun; Chang, Cheng-Yuan; Kuo, Sen M.

    2017-09-01

    The paper presents cancelling duct noises by using the active noise control (ANC) techniques. We use the single channel feed forward algorithm with feedback neutralization to realize ANC. Several kinds of ducts noises including tonal noises, sweep tonal signals, and white noise had investigated. Experimental results show that the proposed ANC system can cancel these noises in a PVC duct very well. The noise reduction of white noise can be up to 20 dB.

  7. Hepatocellular carcinoma with bile duct involvement : computed Tomographic (CT) findings

    International Nuclear Information System (INIS)

    Lee, Joon Woo; Han, Joon Koo; Kim, Tae Kyoung; And others

    2000-01-01

    To describe the radiologic features of computed tomography (CT) in hepatocellular carcinoma (HCC) with bile duct involvement. We retrospectively analyzed the two phase spiral CT findings of 31 patients in whom HCC with bile duct invasion (n=3D28) or compression (n=3D3), was diagnosed. Eight of these underwent follow up CT after transarterial chemoembolization. We analyzed the size, type, location, enhancement pattern, and lipiodol retention of parenchymal and intraductal masses, as well as their lymphadenopathy. In all patients with bile duct invasion, single or multiple masses were demonstrated in the bile ducts. Intraductal masses showed the same enhancement characteristics as the parenchymal mass (kappa 0.550, p less than 0.001), and were contiguous to this mass. In 14 of 28 patients, intraductal masses filled the peripheral intrahepatic bile ducts and extended to the common bile ducts. In the other 14, the parenchymal mass extended to the area of the porta hepatis and then directly invaded the large ducts. In nine of the 28 patients, there was a hypoattenuated cleft between the intraductal mass and ductal wall. In six, a parenchymal mass was not apparent (n=3D2), or was smaller than 2cm (n=3D4). In five of eight patients (62.5%), follow-up CT after transarterial chemoembolization showed compact or partial lipiodol retention within the intraductal mass. In patients with bile duct compression, perihilar lymph nodes were noted along with the dilated intrahepatic duct but no intra ductal mass was demonstrated in the duct. Hepatocellular carcinomas cause bile duct dilatation either by direct invasion or by extrinsic compression of the bile duct with surrounding enlarged nodes. For the diagnosis of this condition, CT is helpful. (author)

  8. Corrosion of valve metals

    International Nuclear Information System (INIS)

    Draley, J.E.

    1976-01-01

    A general survey related to the corrosion of valve metals or film-forming metals. The way these metals corrode with some general examples is described. Valve metals form relatively perfect oxide films with little breakdown or leakage when anodized

  9. Corrosion in Electronics

    DEFF Research Database (Denmark)

    Ambat, Rajan; Gudla, Helene Virginie Conseil; Verdingovas, Vadimas

    2017-01-01

    Electronic control units, power modules, and consumer electronics are used today in a wide variety of varying climatic conditions. Varying external climatic conditions of temperature and humidity can cause an uncontrolled local climate inside the device enclosure. Uncontrolled humidity together...... and high density packing combined with the use of several materials, which can undergo electrochemical corrosion in the presence of water film formed due to humidity exposure and bias conditions on the PCBA surface. This article provides a short review of the corrosion reliability issues of electronics due...... to the use of electronics under varying humidity conditions. Important PCBA aspects, which are fundamental to the corrosion cell formation under humid conditions, are discussed. Effect of hygroscopic residues from the process and service and their role in assisting water film build up and corrosion...

  10. Microbiologically Influenced Corrosion

    Science.gov (United States)

    2009-01-01

    species grow as multicel- lular filaments called hyphae forming a mycelium, some fungal species also grow as single cells. Sexual and asexual...reinforced fluorinated 18 MICROBIOLOGICALLY INFLUENCED CORROSION polyimide composites due to hyphae penetration into resin interiors. The

  11. BWR steel containment corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Tan, C.P.; Bagchi, G.

    1996-04-01

    The report describes regulatory actions taken after corrosion was discovered in the drywell at the Oyster Creek Plant and in the torus at the Nine Mile Point 1 Plant. The report describes the causes of corrosion, requirements for monitoring corrosion, and measures to mitigate the corrosive environment for the two plants. The report describes the issuances of generic letters and information notices either to collect information to determine whether the problem is generic or to alert the licensees of similar plants about the existence of such a problem. Implementation of measures to enhance the containment performance under severe accident conditions is discussed. A study by Brookhaven National Laboratory (BNL) of the performance of a degraded containment under severe accident conditions is summarized. The details of the BNL study are in the appendix to the report.

  12. Corrosion Inhibitors for Aluminum.

    Science.gov (United States)

    Muller, Bodo

    1995-01-01

    Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

  13. Risk factors for central bile duct injury complicating partial liver resection

    NARCIS (Netherlands)

    Boonstra, E. A.; de Boer, M. T.; Sieders, E.; Peeters, P. M. J. G.; de Jong, K. P.; Slooff, M. J. H.; Porte, R. J.

    Background: Bile duct injury is a serious complication following liver resection. Few studies have differentiated between leakage from small peripheral bile ducts and central bile duct injury (CBDI), defined as an injury leading to leakage or stenosis of the common bile duct, common hepatic duct,

  14. Economic importance and application options of some industrial ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-18

    Jul 18, 2008 ... local authorities and industry. ... sludge is a significant part of wastewater treatment pro- gramme. ... duct collected through the normal sewage system. ..... Thermophilic Anaerobic Digestion of Coffee Waste Containing Coffee.

  15. Computed tomography of hepatocellular carcinoma. Dilatation of intrahepatic bile duct

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Soomi; Nakamura, Hitonobu; Tanaka, Ken; Hori, Shinichi; Tokunaga, Kou [Osaka Univ. (Japan). Faculty of Medicine

    1983-10-01

    Based on a series of CT of the liver in 125 patients with hepatoma and 45 patients with metastatic hepatic tumors, the mode of dilatation of the intrahepatic bile duct was examined. In patients with hepatoma, partia dilatations of intrahepatic bile duct were more commonly seen than general dilatations. On the other hand, there was no case of partial dilatation of the intrahepatic bile duct in patients with metastatic hepatic tumors. It could be concluded that partial dilatation of the intrahepatic bile duct is an useful CT finding to make a diagnosis of hepatoma, particularly to differentiate hepatoma from metastatic hepatic tumor.

  16. ATP release, generation and hydrolysis in exocrine pancreatic duct cells

    DEFF Research Database (Denmark)

    Kowal, Justyna Magdalena; Yegutkin, G.G.; Novak, Ivana

    2015-01-01

    Extracellular adenosine triphosphate (ATP) regulates pancreatic duct function via P2Y and P2X receptors. It is well known that ATP is released from upstream pancreatic acinar cells. The ATP homeostasis in pancreatic ducts, which secrete bicarbonate-rich fluid, has not yet been examined. First, ou...... may be important in pancreas physiology and potentially in pancreas pathophysiology....... aim was to reveal whether pancreatic duct cells release ATP locally and whether they enzymatically modify extracellular nucleotides/sides. Second, we wished to explore which physiological and pathophysiological factors may be important in these processes. Using a human pancreatic duct cell line, Capan...

  17. Duct Remediation Program: Engineered access research and construction

    International Nuclear Information System (INIS)

    Beckman, T.D.; Davis, M.M.; Karas, T.M.

    1992-01-01

    The Rocky Flats Plant, Duct Remediation mission concentrated on removing Plutonium Oxide from the process ductwork in the primary Plutonium processing facility. When possible, remediation took place from existing process gloveboxes. Fifteen locations were identified, however, that required accessing duct runs where no process gloveboxes existed. The building's second floor utility areas had many locations where long, inaccessible duct runs were prevalent. Consequently, an extensive program for design, procurement and construction was initiated to contain and isolate ducts for penetration when existing glovebox sites were not present

  18. Occlusion of the cystic duct by electrocoagulation: A radiologic technique

    International Nuclear Information System (INIS)

    Becker, C.D.; Quenville, W.F.; Burhenne, H.J.

    1987-01-01

    Chemical dissolution and extracorporeal shock wave lithotripsy are promising new methods for the treatment of cholelithiasis without cholecystectomy. Nonsurgical defunctionalization of the gallbladder is now required to prevent recurrent stone formation. The authors consider cystic duct occlusion to be the first step. Ten domestic pigs underwent transcatheter electrocoagulation of the cystic duct via a cholecystostomy under fluoroscopic control. Stricture formation was followed by complete cystic duct occlusion in all ten cases. After a follow-up period ranging from 2 to 17 weeks (mean, 13 weeks), the animals were killed. Histologic studies demonstrated that complete obliteration of the cystic duct lumen was due to fibrous scar formation

  19. Thixotropic corrosive gels for nuclear decontamination

    International Nuclear Information System (INIS)

    Bargues, St.

    1998-01-01

    The aim of this thesis was the development of corrosive gels for metallic surface decontamination. These gels formulation, based on a powerful oxidant (the cerium IV), the nitric acid, a mineral charge (silica) and a non ionic surface-active, has been developed according to the specific constraints of the nuclear industry. The objective was to prepare thixotropic gels becoming liquid after shacking to allow an easy pulverization and coming again solid to permit a perfect adhesion on the metallic surface. This rheological study of the gels has been completed by an evaluation of their corrosive properties. The last part of the work presents an industrial utilization during two years. (A.L.B.)

  20. Corrosion of beryllium

    International Nuclear Information System (INIS)

    Mueller, J.J.; Adolphson, D.R.

    1987-01-01

    The corrosion behavior of beryllium in aqueous and elevated-temperature oxidizing environments has been extensively studied for early-intended use of beryllium in nuclear reactors and in jet and rocket propulsion systems. Since that time, beryllium has been used as a structural material in les corrosive environments. Its primary applications include gyro systems, mirror and reentry vehicle structures, and aircraft brakes. Only a small amount of information has been published that is directly related to the evaluation of beryllium for service in the less severe or normal atmospheric environments associated with these applications. Despite the lack of published data on the corrosion of beryllium in atmospheric environments, much can be deduced about its corrosion behavior from studies of aqueous corrosion and the experiences of fabricators and users in applying, handling, processing, storing, and shipping beryllium components. The methods of corrosion protection implemented to resist water and high-temperature gaseous environments provide useful information on methods that can be applied to protect beryllium for service in future long-term structural applications

  1. Monitoring corrosion rates and localised corrosion in low conductivity water

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    2006-01-01

    Monitoring of low corrosion rates and localised corrosion in a media with low conductivity is a challenge. In municipal district heating, quality control may be improved by implementing on-line corrosion monitoring if a suitable technique can be identified to measure both uniform and localised...... corrosion. Electrochemical techniques (LPR, EIS, crevice corrosion current) as well as direct measurement techniques (high-sensitive electrical resistance, weight loss) have been applied in operating plants. Changes in the corrosion processes are best monitored in non-aggressive, low conductivity media...

  2. Use of Computational Fluid Dynamics for improving freeze-dryers design and process understanding. Part 2: Condenser duct and valve modelling.

    Science.gov (United States)

    Marchisio, Daniele L; Galan, Miquel; Barresi, Antonello A

    2018-05-05

    This manuscript shows how computational models, mainly based on Computational Fluid Dynamics (CFD), can be used to simulate different parts of an industrial freeze-drying equipment and to properly design them; in particular in this part the duct connecting the chamber with the condenser, with its valves, is considered, while the chamber design and its effect on drying kinetics have been investigated in Part 1. Such an approach allows a much deeper process understanding and assessment of the critical aspects of lyophilisation. This methodology will be demonstrated on freeze-drying equipment of different sizes, investigating influence of valve type (butterfly and mushroom) and shape on duct conductance and critical flow conditions. The role of the inlet and boundary conditions considered has been assessed, also by modelling the whole apparatus including chamber and condenser, and the influence of the duct diameter has been discussed; the results show a little dependence of the relationship between critical mass flux and chamber pressure on the duct size. Results concerning the fluid dynamics of a simple disk valve, a profiled butterfly valve and a mushroom valve installed in a medium size horizontal condenser are presented. Also in these cases the maximum allowable flow when sonic flow conditions are reached can be described by a correlation similar to that found valid for empty ducts; for the mushroom valve the parameters are dependent on the valve opening length. The possibility to use the equivalent length concept, and to extend the validity of the results obtained for empty ducts will be also discussed. Finally the presence of the inert gas modifies the conductance of the duct, reducing the maximum flow rate of water that can be removed through it before the flow is choked; this also requires a proper over-sizing of the duct (or duct-butterfly valve system). Copyright © 2018. Published by Elsevier B.V.

  3. Effectiveness of duct sealing and duct insulation in multi-family buildings. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Karins, N.H.; Tuluca, A.; Modera, M.

    1997-07-01

    This research investigated the cost-effectiveness of sealing and insulating the accessible portions of duct systems exposed to unconditioned areas in multifamily housing. Airflow and temperature measurements were performed in 25 apartments served by 10 systems a 9 multi-family properties. The measurements were performed before and after each retrofit, and included apartment airflow (supply and return), duct system temperatures, system fan flow and duct leakage area. The costs for each retrofit were recorded. The data were analyzed and used to develop a prototypical multifamily house. This prototype was used in energy simulations (DOE-2.1E) and air infiltration simulations (COMIS 2.1). The simulations were performed for two climates: New York City and Albany. In each climate, one simulation was performed assuming the basement was tight, and another assuming the basement was leaky. Simulation results and average retrofit costs were used to calculate cost-effectiveness. The results of the analysis indicate that sealing leaks of the accessible ductwork is cost-effective under all conditions simulated (simple payback was between 3 and 4 years). Insulating the accessible ductwork, however, is only cost-effective for buildings with leaky basement, in both climates (simple paybacks were less than 5 years). The simple payback period for insulating the ducts in buildings with tight basements was greater than 10 years, the threshold of cost-effectiveness for this research. 13 refs., 5 figs., 27 tabs.

  4. Fluorescent Method for Observing Intravascular Bonghan Duct

    Directory of Open Access Journals (Sweden)

    Byung-Cheon Lee

    2005-12-01

    Full Text Available Observation of intra-vascular threadlike structures in the blood vessels of rats is reported with the images by differential interference contrast microscope, and fluorescence inverted microscope of the acridine-orange stained samples. The confocal microscope image and the hematoxylin-eosin staining revealed the distinctive pattern of nuclei distribution that clearly discerned the threadlike structure from fibrin, capillary, small venule, arteriole, or lymph vessel. Physiological function of the intra-vascular thread in connection with acupuncture is discussed. Especially, this threadlike duct can be a circulation path for herb-liquid flow, which may provide the scientific mechanism for therapeutic effect of herbal acupuncture.

  5. Levitated Duct Fan (LDF) Aircraft Auxiliary Generator

    Science.gov (United States)

    Eichenberg, Dennis J.; Emerson, Dawn C.; Gallo, Christopher A.; Thompson, William K.

    2011-01-01

    This generator concept includes a novel stator and rotor architecture made from composite material with blades attached to the outer rotating shell of a ducted fan drum rotor, a non-contact support system between the stator and rotor using magnetic fields to provide levitation, and an integrated electromagnetic generation system. The magnetic suspension between the rotor and the stator suspends and supports the rotor within the stator housing using permanent magnets attached to the outer circumference of the drum rotor and passive levitation coils in the stator shell. The magnets are arranged in a Halbach array configuration.

  6. JET neutral beam duct Optical Interlock

    Energy Technology Data Exchange (ETDEWEB)

    Ash, A.D.; Jones, T.T.C.; Surrey, E.; Ćirić, D.; Hall, S.I.; Young, D.; Afzal, M.; Hackett, L.; Day, I.E.; King, R.

    2015-10-15

    Highlights: • Optical Interlocks were installed on the JET NBI system as part of the EP2 upgrade. • The system protects the JET tokamak and NBI systems from thermal load damage. • Balmer-α beam emission is used to monitor the neutral beam-line pressure. • We demonstrate an improved trip delay of 2 ms compared to 50 ms before EP2. - Abstract: The JET Neutral Beam Injection (NBI) system is the most powerful neutral beam plasma heating system currently operating. Optical Interlocks were installed on the beam lines in 2011 for the JET Enhancement Project 2 (EP2), when the heating power was increased from 23 MW to 34 MW. JET NBI has two beam lines. Each has eight positive ion injectors operating in deuterium at 80 kV–125 kV (accelerator voltage) and up to 65 A (beam current). Heating power is delivered through two ducts where the central power density can be more than 100 MW/m{sup 2}. In order to deliver this safely, the beam line pressure should be below 2 × 10{sup −5} mbar otherwise the power load on the duct from the re-ionised fraction of the beam is excessive. The new Optical Interlock monitors the duct pressure by measuring the Balmer-α beam emission (656 nm). This is proportional to the instantaneous beam flux and the duct pressure. Light is collected from a diagnostic window and focused into 1-mm diameter fibres. The Doppler shifted signal is selected using an angle-tuned interference filter. The light is measured by a photo-multiplier module with a logarithmic amplifier. The interlock activation time of 2 ms is sufficient to protect the system from a fully re-ionised beam—a significant improvement on the previous interlock. The dynamic range is sufficient to see bremsstrahlung emission from JET plasma and not saturate during plasma disruptions. For high neutron flux operations the optical fibres within the biological shield can be annealed to 350 °C. A self-test is possible by illuminating the diagnostic window with a test lamp and measuring

  7. Thin layer activation: measuring wear and corrosion

    International Nuclear Information System (INIS)

    Delvigne, T.; Leyman, D.; Oxorn, K.

    1995-01-01

    The technique known as thin layer activation (TLA) is explained and assessed in this article. Widely used, in for example the automotive industry, TLA allows on-line monitoring of the loss of matter from a critical surface, by wear erosion and corrosion. The technique offers extremely high sensitivity thus leading to reduced test times. On-line wear phenomena can be assessed during operation of a mechanical process, even through thick engine walls. (UK)

  8. Corrosion evaluation of service water system materials

    International Nuclear Information System (INIS)

    Stein, A.A.; Felder, C.M.; Martin, R.L.

    1994-01-01

    The availability and reliability of the service water system is critical for safe operation of a nuclear power plant. Degradation of the system piping and components has forced utilities to re-evaluate the corrosion behavior of current and alternative system materials, to support assessments of the remaining service life of the service water system, selection of replacement materials, implementation of corrosion protection methods and corrosion monitoring programs, and identification of maintenance and operational constraints consistent with the materials used. TU Electric and Stone and Webster developed a service water materials evaluation program for the Comanche Peak Steam Electric Station. Because of the length of exposure and the generic interest in this program by the nuclear power industry, EPRI joined TU to co-sponsor the test program. The program was designed to evaluate the corrosion behavior of current system materials and candidate replacement materials and to determine the operational and design changes which could improve the corrosion performance of the system. Although the test program was designed to be representative of service water system materials and environments targeted to conditions at Comanche Peak, these conditions are typical of and relevant to other fresh water cooled nuclear service water systems. Testing was performed in raw water and water treated with biocide under typical service water operating conditions including continuous flow, intermittent flow, and stagnant conditions. The test program evaluated the 300 Series and 6% molybdenum stainless steels, copper-nickel, titanium, carbon steel, and a formed-in-place nonmetallic pipe lining to determine susceptibility to general, crevice, and microbiologically influenced corrosion and pitting attack. This report presents the results of the test program after 4 years of exposure

  9. Ultrasonic monitoring of pitting corrosion

    Science.gov (United States)

    Jarvis, A. J. C.; Cegla, F. B.; Bazaz, H.; Lozev, M.

    2013-01-01

    Exposure to corrosive substances in high temperature environments can cause damage accumulation in structural steels, particularly in the chemical and petrochemical industries. The interaction mechanisms are complex and varied; however initial damage propagation often manifests itself in the form of localized areas of increased material loss. Recent development of an ultrasonic wall thickness monitoring sensor capable of withstanding temperatures in excess of 500°C has allowed permanent monitoring within such hostile environments, providing information on how the shape of a pulse which has reflected from a corroding surface can change over time. Reconstructing localized corrosion depth and position may be possible by tracking such changes in reflected pulse shape, providing extra information on the state of the backwall and whether process conditions should be altered to increase plant life. This paper aims to experimentally investigate the effect certain localized features have on reflected pulse shape by `growing' artificial defects into the backwall while wall thickness is monitored using the sensor. The size and complexity of the three dimensional scattering problem lead to the development of a semi-analytical simulation based on the distributed point source method (DPSM) which is capable of simulating pulse reflection from complex surfaces measuring approximately 17×10λ Comparison to experimental results show that amplitude changes are predicted to within approximately 1dB and that pulse shape changes are accurately modelled. All experiments were carried out at room temperature, measurements at high temperature will be studied in the future.

  10. Ultrasound imaging of the mouse pancreatic duct using lipid microbubbles

    Science.gov (United States)

    Banerjee, B.; McKeown, K. R.; Skovan, B.; Ogram, E.; Ingram, P.; Ignatenko, N.; Paine-Murrieta, G.; Witte, R.; Matsunaga, T. O.

    2012-03-01

    Research requiring the murine pancreatic duct to be imaged is often challenging due to the difficulty in selectively cannulating the pancreatic duct. We have successfully catheterized the pancreatic duct through the common bile duct in severe combined immune deficient (SCID) mice and imaged the pancreatic duct with gas filled lipid microbubbles that increase ultrasound imaging sensitivity due to exquisite scattering at the gas/liquid interface. A SCID mouse was euthanized by CO2, a midline abdominal incision made, the common bile duct cut at its midpoint, a 2 cm, 32 gauge tip catheter was inserted about 1 mm into the duct and tied with suture. The duodenum and pancreas were excised, removed in toto, embedded in agar and an infusion pump was used to instill normal saline or lipid-coated microbubbles (10 million / ml) into the duct. B-mode images before and after infusion of the duct with microbubbles imaged the entire pancreatic duct (~ 1 cm) with high contrast. The microbubbles were cavitated by high mechanical index (HMI) ultrasound for imaging to be repeated. Our technique of catheterization and using lipid microbubbles as a contrast agent may provide an effective, affordable technique of imaging the murine pancreatic duct; cavitation with HMI ultrasound would enable repeated imaging to be performed and clustering of targeted microbubbles to receptors on ductal cells would allow pathology to be localized accurately. This research was supported by the Experimental Mouse Shared Service of the AZ Cancer Center (Grant Number P30CA023074, NIH/NCI and the GI SPORE (NIH/NCI P50 CA95060).

  11. Common bile duct cancer with massive necrosis mimicking choledochal dilatation on CT

    International Nuclear Information System (INIS)

    Miyake, H.; Matsumoto, S.; Ueda, S.; Maeda, T.; Aikawa, H.; Mori, H.

    1991-01-01

    Carcinomas of the common bile duct are usually seen as dilatation of the bile duct proximal to a solid mass on CT. In the case reported here, the common bile duct cancer itself mimicked dilated common bile duct on CT because of massive necrosis. In a case of simulating dilated common bile duct on CT, and discrepancy between CT and ultrasonography or endoscopic retrograde cholangiopancreatography, a common bile duct cancer with massive necrosis should be included in the differential diagnosis. (orig.)

  12. Morphological study of pancreatic duct in red jungle fowl | Kadhim ...

    African Journals Online (AJOL)

    Neither goblet cells nor ductal glands were found in the pancreatic ducts. Secretion of both neutral and sulfated materials by the epithelial lining the pancreatic ducts, suggesting that they are acting not only to facilitate the transport of the pancreatic juice, but also as a protective barrier to protect the gland from autodigestion.

  13. Ursodeoxycholic acid treatment of vanishing bile duct syndromes

    NARCIS (Netherlands)

    Pusl, Thomas; Beuers, Ulrich

    2006-01-01

    Vanishing bile duct syndromes (VBDS) are characterized by progressive loss of small intrahepatic ducts caused by a variety of different diseases leading to chronic cholestasis, cirrhosis, and premature death from liver failure. The majority of adult patients with VBDS suffer from primary biliary

  14. Bile duct anastomotic stricture after pediatric living donor liver transplantation.

    Science.gov (United States)

    Chok, Kenneth S H; Chan, See Ching; Chan, Kwong Leung; Sharr, William W; Tam, Paul K H; Fan, Sheung Tat; Lo, Chung Mau

    2012-07-01

    Hepaticojejunostomy is a well-accepted method, whereas duct-to-duct anastomosis is gaining popularity for bile duct reconstruction in pediatric living donor liver transplantation (LDLT). Biliary complications, especially biliary anastomotic stricture (BAS), are not clearly defined. The aim of the present study is to determine the rate of BAS and its associated risk factors. The study included 78 pediatric patients (duct-to-duct anastomosis during LDLT. The median follow-up period for the BAS group and the non-BAS group was 57.8 and 79.5 months, respectively (P = .683). Ten of the patients with BAS required percutaneous transhepatic biliary drainage with or without dilatation for treating the stricture. Multivariable analysis showed that hepatic artery thrombosis and duct-to-duct anastomosis were 2 risk factors associated with BAS. In pediatric LDLT, hepaticojejunostomy is the preferred method for bile duct reconstruction, but more large-scale research needs to be done to reconfirm this result. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Liver and Bile Duct Cancer—Patient Version

    Science.gov (United States)

    Liver cancer includes hepatocellular carcinoma and bile duct cancer (cholangiocarcinoma). Risk factors for HCC include chronic infection with hepatitis B or C and cirrhosis of the liver. Start here to find information on liver and bile duct cancer treatment, causes and prevention, screening, research, and statistics.

  16. Cystic duct closure by sealing with bipolar electrocoagulation

    DEFF Research Database (Denmark)

    Schulze, S; Damgaard, B; Jørgensen, Lars Nannestad

    2010-01-01

    BACKGROUND: Cystic duct leakage after cholecystectomy is not uncommon and is a potentially serious complication. The aim of this study was to assess a bipolar sealing system (LigaSure) for closure of the cystic duct. METHODS: The records from consecutive laparoscopic cholecystectomies performed i...

  17. Magnetic resonance imaging of Muellerian duct anomalies in children

    International Nuclear Information System (INIS)

    Li, Yi; Phelps, Andrew; Zapala, Matthew A.; MacKenzie, John D.; MacKenzie, Tippi C.; Courtier, Jesse

    2016-01-01

    Muellerian duct anomalies encompass a wide variety of disorders resulting from abnormalities in the embryological development of the Muellerian ducts. In the prepubertal pediatric population, Muellerian duct anomalies are often incidental findings on studies obtained for other reasons. The onset of menses can prompt more clinical symptoms. Proper characterization of Muellerian duct anomalies is important because these anomalies can affect the development of gynecological disorders as well as fertility. Muellerian duct anomalies also carry a high association with other congenital anomalies, particularly renal abnormalities. MRI is widely considered the best modality for assessing Muellerian duct anomalies; it provides multiplanar capability, clear anatomical detail and tissue characterization without ionizing radiation. MRI allows for careful description of Muellerian duct anomalies, often leading to classification into the most widely accepted classification system for Muellerian duct anomalies. This system, developed by the American Society of Reproductive Medicine, includes seven subtypes: uterine agenesis/hypoplasia, unicornuate, didelphys, bicornuate, septate, arcuate, and diethylstilbestrol (DES) drug-related uterus. In cases of complex anomalies that defy classification, MRI allows detailed depiction of all components of the anatomical abnormality, allowing for proper management and surgical planning. (orig.)

  18. Surgical management of Stenson's duct injury using epidural catheter

    African Journals Online (AJOL)

    2012-07-05

    Jul 5, 2012 ... Successful management of parotid duct injury depends on early diagnosis and appropriate intervention, failing of ... to diagnose and manage the parotid duct injuries using an “epidural catheter” which is often used for inducing spinal anesthesia. .... Water-soluble contrast media have a definite advantage.

  19. Chloride and potassium conductances of cultured human sweat ducts

    DEFF Research Database (Denmark)

    Novak, I; Pedersen, P S; Larsen, Erik Hviid

    1992-01-01

    The purpose of this study was to characterize the ion conductances, in particular those for Cl- and K+, of human sweat duct cells grown in primary culture. Sweat duct cells from healthy individuals were grown to confluence on a dialysis membrane, which was then mounted in a mini-Ussing chamber an...

  20. Seismic assessment of the Pickering pressure relief duct

    International Nuclear Information System (INIS)

    Ghobarah, A.

    1995-05-01

    The objectives of the study are to examine the structural response of the Pickering pressure relief duct when subjected to earthquake ground motion and to estimate the seismic withstand capacity of various components of the structural system on the basis of performance criteria consistent with the safety function of the duct. (author). 24 refs., 16 tabs., 31 figs

  1. Transcatheter closure of ventricular septal defect with Occlutech Duct Occluder.

    Science.gov (United States)

    Atik-Ugan, Sezen; Saltik, Irfan Levent

    2018-04-01

    Patent ductus arteriosus occluders are used for transcatheter closure of ventricular septal defects, as well as for closure of patent ductus arteriosus. The Occlutech Duct Occluder is a newly introduced device for transcatheter closure of patent ductus arteriosus. Here, we present a case in which the Occlutech Duct Occluder was successfully used on a patient for the closure of a perimembraneous ventricular septal defect.

  2. Evaluation of corrosive behavior of SAE 5155 by corrosion environment

    International Nuclear Information System (INIS)

    An, Jae Pil; Park, Keyung Dong

    2005-01-01

    In this study, the influence of shot peening and corrosive condition for corrosion property was investigated on immersed in 3.5% NaCl, 10% HNO 3 + 3% HF, 6% FeCl 3 . The immersion test was performed on two kinds of specimen. The immersion periods was performed 30days. Corrosion potential, weight loss were investigated from experimental results. From test results, the effect of shot peening on the corrosion was evaluated

  3. Corrosion Surveillance In Pipe By Computed Radiography

    International Nuclear Information System (INIS)

    Nguyen The Man; Dao Duy Dung; Dang Thu Hong; Le Duc Thinh; Ha Hong Thu; Nguyen Trong Nghia

    2014-01-01

    Computed Radiography (CR) is a technique of digital industrial radiology which is developed to replace conventional radiography. With a CR system, the detection of the outer and inner wall surface of the pipe is done usually by edge detection and filter algorithms of the profile line at the position under investigation. Applying in industries, radiographic examination shall be performed in accordance with a written procedure. This paper summarizes collected knowledge and experimental results to establish a procedure for radiography applications in monitoring corrosion in small bore pipes. (author)

  4. An insight in spatial corrosion prediction

    International Nuclear Information System (INIS)

    Mustaffa, Zahiraniza; Gelder, Pieter van; Hashim, Ahmad Mustafa

    2012-01-01

    Recent discoveries on fluid–structure interactions between the external flows and circular cylinders placed close to the wall have added new values to the hydrodynamics of unburied offshore pipelines laid on a sea bed. The hydrodynamics of waves and/or currents introduced vortex flows surrounding the pipeline. External corrosions formed in the pipelines were assumed to be partly contributed by such fluid–structure interactions. The spatial consequences of such interactions were of interest of this study. This paper summarizes selected previous experimental and numerical works reported by literature on these discoveries. Actual field data were utilized in this study for further validation. The characteristics of corrosion orientations in the pipelines were studied comprehensively using simple statistics and results were discussed. Results adopted from the field data acknowledged well to the hypothesis from the reported literature. The updated knowledge from this fluid–structure interaction is hoped to benefit the industry and constructively incorporated into the current subsea pipeline designs. Highlights: ► We attempt to predict spatial corrosions in offshore pipelines. ► We validate the analysis using theories on fluid–structure interactions. ► Vortex flows are assumed to cause external corrosions on pipeline walls. ► More defects are expected for pipelines placed in areas governed by waves.

  5. Corrosion failure analysis as related to prevention of corrosion failures

    International Nuclear Information System (INIS)

    Suss, H.

    1977-10-01

    The factors and conditions which have contributed to many of the corrosion related service failures are discussed based on a review of actual case histories. The anti-corrosion devices which developed as a result of these failure analyses are reviewed, and the method which must be adopted and used to take advantage of the available corrosion prevention techniques is discussed

  6. Positive predictive value of cholescintigraphy in common bile duct obstruction

    International Nuclear Information System (INIS)

    Lecklitner, M.L.; Austin, A.R.; Benedetto, A.R.; Growcock, G.W.

    1986-01-01

    Technetium-99m DISIDA imaging was employed in 400 patients to differentiate obstruction of the common bile duct from medical and other surgical causes of hyperbilirubinemia. Sequential anterior images demonstrated variable degrees of liver uptake, yet there was no evidence of intrabiliary or extrabiliary radioactivity for at least 4 hr after injection in 25 patients. Twenty-three patients were surgically documented to have complete obstruction of the common bile duct. One patient had hepatitis, and another had sickle cell crisis without bile duct obstruction. The remaining patients had either partial or no obstruction of the common bile duct. We conclude that the presence of liver uptake without evident biliary excretion by 4 hr on cholescintigraphy is highly sensitive and predictive of total obstruction of the common bile duct

  7. A Review of Double Common Bile Duct and Its Sequelae.

    Science.gov (United States)

    Kolli, Sindhura; Etienne, Denzil; Reddy, Madhavi; Shahzad, Ghulamullah

    2018-02-01

    A double or accessory common bile duct (ACBD) is a rare congenital anomaly. We report the case of a 60-year-old American Asian male, who was found to have a double or duplicated common bile duct after being admitted for evaluation of a pancreatic mass. A duplicated bile duct has the same mucosa histologically as a single bile duct. However, the opening of a duplicated bile duct lacks a sphincter allowing retrograde flow of gut contents which results in a higher probability of intraductal calculus formation. On rare occasions, it can predispose to liver abscesses, pancreatitis, pancreatic cancer, gallbladder cancer, gastric cancer, and ampullary cancer depending on the location of the opening of the ACBD. We present an integrative review of the limited cases of ACBD with correlation to the current case and discussion regarding the aspects of diagnosis and management.

  8. Cystic duct remnant mucocele in a liver transplant recipient

    Energy Technology Data Exchange (ETDEWEB)

    Ahlawat, Sushil K. [Georgetown University Hospital, Department of Medicine, Division of Gastroenterology, Washington, DC (United States); University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, NJ (United States); Fishbien, Thomas M. [Georgetown University Hospital, Department of Medicine, Division of Gastroenterology, Washington, DC (United States); Haddad, Nadim G. [Georgetown University Hospital, Department of Surgery, Division of Transplant Surgery, Washington, DC (United States)

    2008-08-15

    Cystic duct remnant mucocele is an extremely rare complication of liver transplantation in children. Surgical correction is usually required for cystic duct remnant mucocele when it causes biliary obstruction. We describe a 14-month-old liver transplant recipient who presented with biliary obstruction 1 month after orthotopic liver transplantation with an end-to-end choledochocholedocal biliary anastomosis for hepatoblastoma. US, CT and cholangiography findings were consistent with mucocele of the allograft cystic duct remnant. Surgery was not needed in our patient because the mucocele and biliary obstruction had resolved on repeat imaging most likely due to guidewire manipulation during cholangiography, resulting in opening of the cystic duct remnant orifice and drainage into the common duct. (orig.)

  9. Cystic duct remnant mucocele in a liver transplant recipient

    International Nuclear Information System (INIS)

    Ahlawat, Sushil K.; Fishbien, Thomas M.; Haddad, Nadim G.

    2008-01-01

    Cystic duct remnant mucocele is an extremely rare complication of liver transplantation in children. Surgical correction is usually required for cystic duct remnant mucocele when it causes biliary obstruction. We describe a 14-month-old liver transplant recipient who presented with biliary obstruction 1 month after orthotopic liver transplantation with an end-to-end choledochocholedocal biliary anastomosis for hepatoblastoma. US, CT and cholangiography findings were consistent with mucocele of the allograft cystic duct remnant. Surgery was not needed in our patient because the mucocele and biliary obstruction had resolved on repeat imaging most likely due to guidewire manipulation during cholangiography, resulting in opening of the cystic duct remnant orifice and drainage into the common duct. (orig.)

  10. Scintigraphy of cysts of the common bile duct in children

    International Nuclear Information System (INIS)

    Mironov, S.P.; Akopyan, V.G.; Murieva, Z.D.; Tumanyan, G.T.; Mironova, E.S.

    1984-01-01

    Cyst of the common bile duct, the most frequent variant of cystic dilatation of the extrahepatic biliary tract, represents a serious diagnostic problem. 13 children with cysts of the common bile duct were studied by the method of dynamic scintigraphy with sup(99m)Tc-HIDA. The scintigraphic picture was characterized by the following signs: sacculated or spheroidal dilatation of the common bile duct, dilatation of the left or both lobular bile ducts, absence of the gall bladder visualization. Change of indicators of the hepatic function and the time of interstinal visualization reflects both the disorder of distal parts permeability and the degree of cyst drainage. An experience of radioisotropic cholegraphy application reveals, that the efficiency of preoperational diagnosis of cysts of the common bile duct increases as a result of the more accurate evaluation of the dynamic of improvement of absorptive-excretory hepatic function after different variants of operations

  11. Consistent approach to air-cleaning system duct design

    International Nuclear Information System (INIS)

    Miller, W.H.; Ornberg, S.C.; Rooney, K.L.

    1981-01-01

    Nuclear power plant air-cleaning system effectiveness is dependent on the capability of a duct system to safely convey contaminated gas to a filtration unit and subsequently to a point of discharge. This paper presents a logical and consistent design approach for selecting sheet metal ductwork construction to meet applicable criteria. The differences in design engineers' duct construction specifications are acknowledged. Typical duct construction details and suggestions for their effective use are presented. Improvements in duct design sections of ANSI/ASME N509-80 are highlighted. A detailed leakage analysis of a control room HVAC system is undertaken to illustrate the effects of conceptual design variations on duct construction requirements. Shortcomings of previously published analyses and interpretations of a current standard are included

  12. Study of the uniform corrosion of non alloy and stainless steels: combined utilization of acoustic emission and electrochemical techniques

    International Nuclear Information System (INIS)

    Jaubert, Lionel

    2004-01-01

    In chemical and petrochemical industry, uniform corrosion induces important economic and security disappointments. The mechanisms of this damaging corrosion mode are well understood, but methods for on-line detection are badly missing. Acoustic emission technique presents, to palliate this lack, potentialities that have been studied in an instrumented laboratory loop allowing the simulation of industrial uniform corrosion conditions. In acidic media, acoustic activity is related to the hydrogen evolution resulting from proton reduction; it is therefore well correlated to the damage severity. In neutral aerated media, the deposit formation of corrosion products is not very emissive. Yet, a specific study of frequency parameters allows detection of corrosion evolution, but in that case, the quantification of corrosion rate remains difficult. A subsidiary study confirms the technique applicability in the case of 'acidic' corrosion, even in very noisy conditions. (author) [fr

  13. Corrosion testing facilities in India

    International Nuclear Information System (INIS)

    Viswanathan, R.; Subramanian, Venu

    1981-01-01

    Major types of corrosion tests, establishment of specifications on corrosion testing and scope of their application in practice are briefly described. Important organizations in the world which publish specifications/standards are listed. Indian organizations which undertake corrosion testing and test facilities available at them are also listed. Finally in an appendix, a comprehensive list of specifications relevant to corrosion testing is given. It is arranged under the headings: environmental testing, humidity tests, salt spray/fog tests, immersion tests, specification corrosion phenomena, (tests) with respect to special corrosion media, (tests) with respect to specific corrosion prevention methods, and specific corrosion tests using electrical and electrochemical methods (principles). Each entry in the list furnishes information about: nature of the test, standard number, and its specific application. (M.G.B.)

  14. Functionalizable Sol-Gel Silica Coatings for Corrosion Mitigation

    Science.gov (United States)

    Gąsiorek, Jolanta; Babiarczuk, Bartosz; Kaleta, Jerzy; Jones, Walis; Krzak, Justyna

    2018-01-01

    Corrosion is constantly a major problem of the world economy in the field of metal products, metal processing and other areas that utilise metals. Previously used compounds utilizing hexavalent chromium were amongst the most effective materials for corrosion protection but regulations have been recently introduced that forbid their use. Consequently, there is a huge drive by engineers, technologists and scientists from different disciplines focused on searching a new, more effective and environmentally-friendly means of corrosion protection. One novel group of materials with the potential to solve metal protection problems are sol-gel thin films, which are increasingly interesting as mitigation corrosion barriers. These environmentally-friendly and easy-to-obtain coatings have the promise to be an effective alternative to hexavalent chromium compounds using for anti-corrosion industrial coatings. In this review the authors present a range of different solutions for slow down the corrosion processes of metallic substrates by using the oxides and doped oxides obtained by the sol-gel method. Examples of techniques used to the sol-gel coating examinations, in terms of anti-corrosion protection, are also presented. PMID:29373540

  15. Functionalizable Sol-Gel Silica Coatings for Corrosion Mitigation

    Directory of Open Access Journals (Sweden)

    Jolanta Gąsiorek

    2018-01-01

    Full Text Available Corrosion is constantly a major problem of the world economy in the field of metal products, metal processing and other areas that utilise metals. Previously used compounds utilizing hexavalent chromium were amongst the most effective materials for corrosion protection but regulations have been recently introduced that forbid their use. Consequently, there is a huge drive by engineers, technologists and scientists from different disciplines focused on searching a new, more effective and environmentally-friendly means of corrosion protection. One novel group of materials with the potential to solve metal protection problems are sol-gel thin films, which are increasingly interesting as mitigation corrosion barriers. These environmentally-friendly and easy-to-obtain coatings have the promise to be an effective alternative to hexavalent chromium compounds using for anti-corrosion industrial coatings. In this review the authors present a range of different solutions for slow down the corrosion processes of metallic substrates by using the oxides and doped oxides obtained by the sol-gel method. Examples of techniques used to the sol-gel coating examinations, in terms of anti-corrosion protection, are also presented.

  16. Functionalizable Sol-Gel Silica Coatings for Corrosion Mitigation.

    Science.gov (United States)

    Gąsiorek, Jolanta; Szczurek, Anna; Babiarczuk, Bartosz; Kaleta, Jerzy; Jones, Walis; Krzak, Justyna

    2018-01-26

    Corrosion is constantly a major problem of the world economy in the field of metal products, metal processing and other areas that utilise metals. Previously used compounds utilizing hexavalent chromium were amongst the most effective materials for corrosion protection but regulations have been recently introduced that forbid their use. Consequently, there is a huge drive by engineers, technologists and scientists from different disciplines focused on searching a new, more effective and environmentally-friendly means of corrosion protection. One novel group of materials with the potential to solve metal protection problems are sol-gel thin films, which are increasingly interesting as mitigation corrosion barriers. These environmentally-friendly and easy-to-obtain coatings have the promise to be an effective alternative to hexavalent chromium compounds using for anti-corrosion industrial coatings. In this review the authors present a range of different solutions for slow down the corrosion processes of metallic substrates by using the oxides and doped oxides obtained by the sol-gel method. Examples of techniques used to the sol-gel coating examinations, in terms of anti-corrosion protection, are also presented.

  17. Understanding and managing corrosion in nuclear power plants

    International Nuclear Information System (INIS)

    Johnson, A.B. Jr.; Jarrell, D.B.; Sinha, U.P.; Shah, V.N.

    1991-03-01

    The main theme of this paper is a concept: understanding and managing corrosion in nuclear power plants. The concept is not new--in various forms the concept has been applied throughout the development and maturing of nuclear technology. However, the concept has frequently not been well conceived and applied. Too often, understanding corrosion has been based on reaction rather than on anticipation. Regulatory and utility industry initiatives are creating a climate and framework for more effective application of the concept. This paper characterizes the framework and provides some illustrations of how the concept is being applied, drawing from work conducted under the Nuclear Plant Aging Research (NPAR) Program, sponsored by the Nuclear Regulatory Commission's (NRCs) Office of Research. Nuclear plants are becoming an increasingly important factor in the national electrical grid. Initiatives are currently underway to extend the operating licenses beyond the current 40-year period and to evaluate advanced reactor designs the feature higher safety factors. Corrosion has not caused a major nuclear accident, but numerous corrosion mechanisms, have degraded nuclear systems and components. New corrosion phenomena continue to appear, and occasionally corrosion phenomena cause reactor shutdowns. Effective application of understanding and managing corrosion is important to safe and economic operation of the nuclear plants and also to public perception of a soundly operated technology. 53 refs., 11 figs., 5 tabs

  18. A Plug-and-Play Duct System Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Beach, R. [IBACOS, Inc., Pittsburgh, PA (United States); Dickson, B. [IBACOS, Inc., Pittsburgh, PA (United States); Grisolia, A. [IBACOS, Inc., Pittsburgh, PA (United States); Poerschke, A. [IBACOS, Inc., Pittsburgh, PA (United States); Rapport, A. [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-07-01

    This report describes an air distribution system composed of a series of uniformly-sized ducts that terminate in rooms throughout the home and return to a central manifold, similar in fashion to a “home-run” cross-linked polyethylene plumbing system. With a well-designed manifold, each duct receives an equal static pressure potential for airflow from the air handling unit, and the number of needed ducts for each room are simply attached to fittings located on the manifold; in this sense, the system is plug-and-play (PnP). As indicated, all ducts in the PnP system are identical in size and small enough to fit in the ceiling and wall cavities of a house (i.e., less than 3.5-in. outer diameter). These ducts are also more appropriately sized for the lower airflow requirements of modern, energy-efficient homes; therefore, the velocity of the air moving through the duct is between that of conventional duct systems (approximately 700 ft/min) and high-velocity systems (more than 1,500 ft/min) on the market today. The PnP duct system uses semi-rigid plastic pipes, which have a smooth inner wall and are straightforward to install correctly, resulting in a system that has minimal air leakage. However, plastic ducts are currently not accepted by code for use in residential buildings; therefore, the project team considered other duct materials for the system that are currently accepted by code, such as small-diameter, wirehelix, flexible ductwork.

  19. A Plug-and-Play Duct System Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Beach, Robert [IBACOS, Inc., Pittsburgh, PA (United States); Dickson, Bruce [IBACOS, Inc., Pittsburgh, PA (United States); Grisolia, Anthony [IBACOS, Inc., Pittsburgh, PA (United States); Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States); Rapport, Ari [IBACOS, Inc., Pittsburgh, PA (United States)

    2017-07-10

    This report describes an air distribution system composed of a series of uniformly-sized ducts that terminate in rooms throughout the home and return to a central manifold, similar in fashion to a “home-run” cross-linked polyethylene plumbing system. With a well-designed manifold, each duct receives an equal static pressure potential for airflow from the air handling unit, and the number of needed ducts for each room are simply attached to fittings located on the manifold; in this sense, the system is plug-and-play (PnP). As indicated, all ducts in the PnP system are identical in size and small enough to fit in the ceiling and wall cavities of a house (i.e., less than 3.5-in. outer diameter). These ducts are also more appropriately sized for the lower airflow requirements of modern, energy-efficient homes; therefore, the velocity of the air moving through the duct is between that of conventional duct systems (approximately 700 ft/min) and high-velocity systems (more than 1,500 ft/min) on the market today. The PnP duct system uses semi-rigid plastic pipes, which have a smooth inner wall and are straightforward to install correctly, resulting in a system that has minimal air leakage. However, plastic ducts are currently not accepted by code for use in residential buildings; therefore, the project team considered other duct materials for the system that are currently accepted by code, such as small-diameter, wirehelix, flexible ductwork.

  20. Self-retaining small-looped catheter for narrow bile ducts in high common bile duct obstruction

    International Nuclear Information System (INIS)

    Guenther, R.W.; Daehnert, W.

    1985-01-01

    A new self-retaining catheter was devised for percutaneous drainage of small bile ducts. The device allows safe external drainage without the risk of catheter dislocation even in high bile duct obstruction. The catheter is also suitable for percutaneous nephrostomy in non-dilated pyelocaliceal system. (orig.)

  1. Acid corrosion inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Chen, N G

    1964-04-28

    An acid corrosion inhibitor is prepared by a 2-stage vacuum evaporation of effluents obtained from the ammonia columns of the coking oven plant. The effluent, leaving a scrubber in which the phenols are removed at a temperature of 98$C, passes through a quartz filter and flows into a heated chamber in which it is used for preheating a solution circulating through a vacuum unit, maintaining the temperature of the solution at 55$ to 60$C. The effluent enters a large tank in which it is boiled at 55$ to 60$C under 635 to 640 mm Hg pressure. Double evaporation of this solution yields a very effective acid corrosion inhibitor. Its corrosion-preventing effect is 97.9% compared with 90.1% for thiourea and 88.5% for urotropin under identical conditions.

  2. Plastics for corrosion inhibition

    CERN Document Server

    Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

    2005-01-01

    The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

  3. Stochastic theory of fatigue corrosion

    Science.gov (United States)

    Hu, Haiyun

    1999-10-01

    A stochastic theory of corrosion has been constructed. The stochastic equations are described giving the transportation corrosion rate and fluctuation corrosion coefficient. In addition the pit diameter distribution function, the average pit diameter and the most probable pit diameter including other related empirical formula have been derived. In order to clarify the effect of stress range on the initiation and growth behaviour of pitting corrosion, round smooth specimen were tested under cyclic loading in 3.5% NaCl solution.

  4. Corrosion-resistant metal surfaces

    Science.gov (United States)

    Sugama, Toshifumi [Wading River, NY

    2009-03-24

    The present invention relates to metal surfaces having thereon an ultrathin (e.g., less than ten nanometer thickness) corrosion-resistant film, thereby rendering the metal surfaces corrosion-resistant. The corrosion-resistant film includes an at least partially crosslinked amido-functionalized silanol component in combination with rare-earth metal oxide nanoparticles. The invention also relates to methods for producing such corrosion-resistant films.

  5. Ship ballast tanks a review from microbial corrosion and electrochemical point of view

    NARCIS (Netherlands)

    Heyer, A.; D'Souza, F.; Morales, C.F.L.; Ferrari, G.; Mol, J.M.C.; Wit, J.H.W. de

    2013-01-01

    Microbiologically Influenced Corrosion (MIC) is the term used for the phenomenon in which corrosion is initiated and/or accelerated by the activities of microorganisms. MIC is a very serious problem for the ship industry as it reduces structural lifetime in combination with safety risks for

  6. Sedimentibacter sp. With corrosive capability, Ferric-reducing, isolated from an oil separation tank

    International Nuclear Information System (INIS)

    Lopez-Jimenez, G.; Loera, O.; Ramirez, F.; Monroy, O.; Fernandez-Linares, L. C.

    2009-01-01

    Bio corrosion is a common problem in oil and gas industry facilities. characterization of the microbial populations responsible for bio corrosion and the interactions between different microorganisms with metallic surfaces is required in order to implemented efficient monitoring and control strategies. (Author)

  7. Corrosion Protection of Steel by Thin Coatings of Starch-oil Emulsions

    Science.gov (United States)

    Corrosion of materials is one of the most serious and challenging problems faced worldwide by industry. This research investigated the inhibition of corrosive behavior by jet-cooked starch-soybean oil composites on SAE 1010 steel. Electrochemical Impedance Spectroscopy (EIS) was used to evaluate t...

  8. Corrosion protection of steel by thin coatings of starch-oil dry lubricants

    Science.gov (United States)

    Corrosion of materials is one of the most serious and challenging problems faced worldwide by industry. Dry lubricants reduce friction between two metal surfaces. This research investigated the inhibition of corrosive behavior a dry lubricant formulation consisting of jet-cooked corn starch and soyb...

  9. Full-signature real-time corrosion detection of underground casing pipes

    NARCIS (Netherlands)

    Yin, Jiming; Lu, Mi; Pineda de Gyvez, J.

    2000-01-01

    Corrosion monitoring and early detection of pits and wall thinning for casing pipes are considerably important to gas and petroleum industries since the frequently occurring corrosion at the internal or external parts of those steel casing pipes used in underground gas storage or oil fields causes

  10. Rhenium corrosion in chloride melts

    International Nuclear Information System (INIS)

    Stepanov, A.D.; Shkol'nikov, S.N.; Vetyukov, M.M.

    1989-01-01

    The results investigating rhenium corrosion in chloride melts containing sodium, potassium and chromium ions by a gravimetry potentials in argon atmosphere in a sealing quarth cell are described. Rhenium corrosion is shown to be rather considerable in melts containing CrCl 2 . The value of corrosion rate depending on temperature is determined

  11. Corrosion behavior of zinc-nickel alloy electrodeposited coatings

    Energy Technology Data Exchange (ETDEWEB)

    Fabri Miranda, F.J. [USIMINAS, Ipatinga, Minas Gerais (Brazil); Margarit, I.C.P.; Mattos, O.R.; Barcia, O.E. [UFRJ, Rio de Janeiro (Brazil); Wiart, R. [Univ. Pierre et M. Curie, Paris (France)

    1999-08-01

    Various types of zinc-electrocoated steel sheets are used to improve the durability of car bodies. Among these coatings, the Zn-Ni alloy has higher corrosion resistance than pure Zn, as well as better welding and painting properties. The corrosion mechanism of the Zn-Ni alloy has been investigated mainly on the basis of accelerated tests and electrochemical measurements. There are few data about long-term corrosion tests. In the present study, the behavior of unpainted Zn-Ni alloy coated steel was studied during 3 years of exposure in industrial and marine environments. Electrochemical impedance spectroscopy (EIS) and surface analysis (scanning electron microscopy [SEM] and Auger electron spectroscopy [AES]) were the experimental techniques used. Long-term atmospheric corrosion mechanism of Zn-Ni coatings was discussed and compared with that proposed based on short-term tests.

  12. Corrosion Detection of Reinforcement of Building Materials with Piezoelectric Sensors

    Directory of Open Access Journals (Sweden)

    Jia Peng

    2017-06-01

    Full Text Available The extensive use of reinforced materials in the construction industry has raised increased concerns about their safety and durability, while corrosion detection of steel materials is becoming increasingly important. For the scientific management, timely repair and health monitoring of construction materials, as well as to ensure construction safety and prevent accidents, this paper investigates corrosion detection on construction materials based on piezoelectric sensors. At present, the commonly used corrosion detection methods include physical and electrochemical methods, but there are shortcomings such as large equipment area, low detection frequency, and complex operation. In this study an improved piezoelectric ultrasonic sensor was designed, which could not only detect the internal defects of buildings while not causing structural damage, but also realize continuous detection and enable qualitative and quantitative assessment. Corrosion detection of reinforced building materials with piezoelectric sensors is quick and accurate, which can find hidden dangers and provide a reliable basis for the safety of the buildings.

  13. Accelerated cyclic corrosion tests

    Directory of Open Access Journals (Sweden)

    Prošek T.

    2016-06-01

    Full Text Available Accelerated corrosion testing is indispensable for material selection, quality control and both initial and residual life time prediction for bare and painted metallic, polymeric, adhesive and other materials in atmospheric exposure conditions. The best known Neutral Salt Spray (NSS test provides unrealistic conditions and poor correlation to exposures in atmosphere. Modern cyclic accelerated corrosion tests include intermittent salt spray, wet and dry phases and eventually other technical phases. They are able to predict the material performance in service more correctly as documented on several examples. The use of NSS should thus be restricted for quality control.

  14. Achievments of corrosion science and corrosion protection technology

    International Nuclear Information System (INIS)

    Fontana, M.; Stehjl, R.

    1985-01-01

    Problems of corrosion-mechanical strength of metals, effect of corrosive media on creep characteristics are presented. New concepts of the mechanism of corrosion cracking and its relation to hydrogen embrittlement are described. Kinetics and mechanism of hydrogen embrittlement effect on the process of corrosion cracking of different steels and alloys are considered. The dependence of such types of failure on various structural factors is shown. Data on corrosion cracking of high-strength aluminium and titanium alloys, mechanism of the processes and protective methods are given

  15. Benign bile duct stenosis: diagnosis and treatment

    International Nuclear Information System (INIS)

    Garcia-Medina, J.; Casal, M.; Vieito, X.

    1997-01-01

    The bening injuries of the biliary ducts are relatively little frequent. Exist two groups of injuries: to due to them to a series for responsible pathologies for itself of the such injuries training, and that basically are the sclerosant cholangitis, the chronic pancreatitis and the stenosis of the sfinter of Oddi, and related them to previous surgery. On both groups eitological, the interventional radiology occupies a place in the diagnosis as well as in the treatment, complementing or substituting to the surgery. Due to the greater frequency of the postchirurgical injuries, we have centered us basically in them. We make a review of the current state of the topic and a bibliographical tracking, emphasizing the most relevant projects. We show some clinical cases of our subject-specific experience. (Author) 42 refs

  16. Thermal spray coating for corrosion under insulation (CUI) prevention

    Science.gov (United States)

    Fuad, Mohd Fazril Irfan Ahmad; Razak, Khalil Abdul; Alias, Nur Hashimah; Othman, Nur Hidayati; Lah, Nik Khairul Irfan Nik Ab

    2017-12-01

    Corrosion under insulation (CUI) is one of the predominant issues affecting process of Oil and Gas and Petrochemical industries. CUI refers to external corrosion, but it is difficult to be detected as the insulation cover masks the corrosion problem. One of the options to prevent CUI is by utilizing the protective coating systems. Thermal spray coating (TSC) is an advanced coating system and it shows promising performance in harsh environment, which could be used to prevent CUI. However, the application of TSC is not attractive due to the high initial cost. This work evaluates the potential of TSC based on corrosion performance using linear polarization resistance (LPR) method and salt spray test (SST). Prior to the evaluation, the mechanical performance of TSC was first investigated using adhesion test and bend test. Microstructure characterization of the coating was investigated using Scanning Electron Microscope (SEM). The LPR test results showed that low corrosion rate of 0.05 mm/years was obtained for TSC in compared to the bare steel especially at high temperature of 80 °C, where usually normal coating would fail. For the salt spray test, there was no sign of corrosion products especially at the center (fully coated region) was observed. From SEM images, no corrosion defects were observed after 336 hours of continuous exposure to salt fog test. This indicates that TSC protected the steel satisfactorily by acting as a barrier from a corrosive environment. In conclusion, TSC can be a possible solution to minimize the CUI in a long term. Further research should be done on corrosion performance and life cycle cost by comparing TSC with other conventional coating technology.

  17. Study on corrosion of thermal power plant condenser tubes

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, Abdolreza Rashidi; Zhaam, Ali Akbar [Niroo Research Institute, end of Poonak Bakhtari blvd., Shahrak Ghods, Tehran (Iran)

    2004-07-01

    The aim of this investigation is to study kinds of corrosion mechanisms in thermal power plant condenser tubes. Condenser is a shell and tube heat exchanger in which cooling water flows through its tubes. While the steam from low pressure turbine passes within condenser tubes, it is condensed by cooling water. The exhausted steam from low pressure turbine is condensed on external surface of condenser tubes and heat is transferred to cooling water which flow into tubes. Tubes composition is usually copper-based alloys, stainless steel or titanium. Annual damages due to corrosion cause much cost for replacement and repairing metallic equipment and installations in electric power industry. Because of existence of different contaminants in water and steam cycle, condenser tubes surfaces are exposed to corrosion. Contaminants like oxygen, carbon dioxide, chloride ion and ammonia in water and steam cycle originate several damages such as pitting and crevice corrosion, erosion, galvanic attack, SCC, condensed corrosion, de-alloying in thermal power plant condenser. The paper first states how corrosion damage takes place in condensers and then introduces types of usual alloys used in condensers and also their corrosion behavior. In continuation, a brief explanation is presented about kinds of condenser failures due to corrosion. Then, causes and locations of different mechanisms of corrosion events on condenser tubes and effects of different parameters such as composition, temperature, chloride and sulfide ion concentration, pH, water velocity and biological precipitation are examined and finally protection methods are indicated. Also some photos of tubes specimens related to power plants are studied and described in each case of mentioned mechanisms. (authors)

  18. Modeling pore corrosion in normally open gold- plated copper connectors.

    Energy Technology Data Exchange (ETDEWEB)

    Battaile, Corbett Chandler; Moffat, Harry K.; Sun, Amy Cha-Tien; Enos, David George; Serna, Lysle M.; Sorensen, Neil Robert

    2008-09-01

    The goal of this study is to model the electrical response of gold plated copper electrical contacts exposed to a mixed flowing gas stream consisting of air containing 10 ppb H{sub 2}S at 30 C and a relative humidity of 70%. This environment accelerates the attack normally observed in a light industrial environment (essentially a simplified version of the Battelle Class 2 environment). Corrosion rates were quantified by measuring the corrosion site density, size distribution, and the macroscopic electrical resistance of the aged surface as a function of exposure time. A pore corrosion numerical model was used to predict both the growth of copper sulfide corrosion product which blooms through defects in the gold layer and the resulting electrical contact resistance of the aged surface. Assumptions about the distribution of defects in the noble metal plating and the mechanism for how corrosion blooms affect electrical contact resistance were needed to complete the numerical model. Comparisons are made to the experimentally observed number density of corrosion sites, the size distribution of corrosion product blooms, and the cumulative probability distribution of the electrical contact resistance. Experimentally, the bloom site density increases as a function of time, whereas the bloom size distribution remains relatively independent of time. These two effects are included in the numerical model by adding a corrosion initiation probability proportional to the surface area along with a probability for bloom-growth extinction proportional to the corrosion product bloom volume. The cumulative probability distribution of electrical resistance becomes skewed as exposure time increases. While the electrical contact resistance increases as a function of time for a fraction of the bloom population, the median value remains relatively unchanged. In order to model this behavior, the resistance calculated for large blooms has been weighted more heavily.

  19. Experiments and calculations on neutron streaming through bent ducts

    Energy Technology Data Exchange (ETDEWEB)

    Kloosterman, J.L.; Hoogenboom, J.E. (Delft Univ. of Technology (Netherlands). Interfaculty Reactor Inst.); Zsolnay, E.M.

    1993-07-01

    Neutron spectra in a cylindrical straight duct and in bent ducts with angles of 30deg, 60deg and 90deg have been measured by the multiple foil activation and thermoluminescence dosimetry methods. Two-dimensional discrete ordinates and three-dimensional Monte Carlo calculations are executed, and the results are compared with the measurements. The flow rate at the duct entrance calculated by the DOT3.5 code is underestimated by approximately 30 %, due to a conversion of the core and reflector geometry from XY to RZ geometry. The fast neutron flux in the ducts is underestimated by 20 % by the MORSE-SGC/S code due to a too coarse angular mesh of the source, which does not properly represent the actual angular distribution of the fast flux, which is highly peaked forwardly into the ducts. The thermal neutron flux was over-estimated by the Monte Carlo calculation. A method is proposed to calculate the angular distribution of the flow rate at the duct entrance and to calculate the source strength and the angular distribution of the flow rate at the entrance of the second leg of the duct. The results are compared with those of the transport calculations. Generally, the agreement is quite satisfactory. (author).

  20. Water condensation promotes fungal growth in ventilation ducts

    Energy Technology Data Exchange (ETDEWEB)

    Pasanen, P.; Pasanen, A.-L. (University of Kupopio, Department of Environmental Sciences, Kuopio (Finland)); Jantunen, M. (National Public Health Institute, Kuopio (Finland))

    1993-01-01

    In a subarctic climate the diurnal variation in temperature may cause water condensation in ducts placed in the unheated spaces of a building. In this study, germination time and sporulation of a fungus, Penicillium verrucosum, were studied on dusty, galvanized steel sheet under different moisture conditions at room temperature. The effect of condensed water in a supply air duct on spore amplification was studied in an experimental ventilation set-up. In the field, air temperatures and the dew point temperature of air in the duct were monitored continuously for a week. P. verrucosum germinated on steel surfaces during five-hour incubation of the surface under humid conditions, when the surface has been moist for half an hour, germ tubes appeared within 17 hours. During 24-hour incubation under moist conditions, P. verrucosum produced hyphae and spores. In the experimental set-up the airborne spore counts increased when the air passed through a water-condensing section of the duct. Penicillium was the most abundant fungus sporulated on the moist duct surface. In the field, during humid weather, the surface temperature on the air stream surface decreased to the dew point temperature of the air in the duct. thus water condensation in air ducts may promote fungal growth. (au)

  1. Anatomic relationship of intrahepatic bile ducts to portal veins revisited

    International Nuclear Information System (INIS)

    Bret, P.M.; Stempel, J.; Atri, M.; Lough, J.O.; Illescas, F.F.

    1987-01-01

    It is well accepted that intrahepatic bile ducts lie in front of corresponding portal vein branches. Since the authors' clinical experience with US was different, they studied 18 normal necropsy cadaver livers. The common bile duct, main portal vein, and hepatic artery were cannulated and injected respectively with air, dilute contrast medium, and mineral oil. The livers were then examined in anatomic position with CT. In the left lobe of the liver, the bile ducts were anterior to the portal vein in seven cases, posterior in seven cases, and were tortuous both anterior and posterior in three cases. In the right lobe, the bile ducts were anterior in nine cases, posterior in five cases, tortuous in one case, and not seen in two cases. In the porta hepatis, the bile ducts were anterior in eight cases, posterior in one case, tortuous in five cases, and not seen in three cases. Histologic specimens confirmed the anterior and posterior location of the bile ducts relative to the portal veins. In conclusion, intrahepatic bile ducts can be either anterior or posterior to the corresponding portal vein branches

  2. Cystic Duct Closure by Sealing With Bipolar Electrocoagulation

    Science.gov (United States)

    Damgaard, B.; Jorgensen, L. N.; Larsen, S. S.; Kristiansen, V. B.

    2010-01-01

    Background: Cystic duct leakage after cholecystectomy is not uncommon and is a potentially serious complication. The aim of this study was to assess a bipolar sealing system (LigaSure®) for closure of the cystic duct. Methods: The records from consecutive laparoscopic cholecystectomies performed in 2 hospitals with closure of the cystic duct with LigaSure after informed consent were recorded and complications and morbidity registered. The records were compared with those of patients undergoing laparoscopic cholecystectomy with closure of the cystic duct with clips during the same period. Results: During the study period, 218 laparoscopic cholecystectomies were performed; 102 of these were performed with the LigaSure. One patient was excluded due to violation of the protocol. We experienced no cases of cystic duct leakage, but in one patient, bile leakage from the gallbladder bed was observed probably due to a small aberrant duct. Conclusion: The LigaSure system was safe and effective for closure and division of the cystic duct in laparoscopic cholecystectomy. PMID:20412641

  3. Industrial experience with titanium

    International Nuclear Information System (INIS)

    Ikeda, B.M.; Shoesmith, D.W.

    1997-09-01

    Titanium is a reference material for the construction of waste containers in the Canadian Nuclear Fuel Waste Management Program. It has been in industrial service for over 30 a, often in severe corrosion environments, but it is still considered a relatively exotic material with limited operating history. This has arisen because of the aerospace applications of this material and the misconception that the high strength-to-weight ratio dominates the choice of this material. In fact, the advantage of titanium lies in its high reliability and excellent corrosion resistance. It has a proven record in seawater heat exchanger service and a demonstrated excellent reliability even in polluted water. For many reasons it is the technically correct choice of material for marine applications. In this report we review the industrial service history of titanium, particularly in hot saline environments, and demonstrate that it is a viable waste container material, based upon this industrial service history and operating experience. (author)

  4. Irradiation Assisted Stress Corrosion Cracking of austenitic stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Tsukada, Takashi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    Irradiation Assisted Stress Corrosion Cracking (IASCC) of austenitic stainless steels in oxygenated high temperature water was studied. The IASCC failure has been considered as a degradation phenomenon potential not only in the present light water reactors but rather common in systems where the materials are exposed simultaneously to radiation and water environments. In this study, effects of the material and environmental factors on the IASCC of austenitic stainless steels were investigated in order to understand the underlying mechanism. The following three types of materials were examined: a series of model alloys irradiated at normal water-cooled research reactors (JRR-3M and JMTR), the material irradiated at a spectrally tailored mixed-spectrum research reactor (ORR), and the material sampled from a duct tube of a fuel assembly used in the experimental LMFBR (JOYO). Post-irradiation stress corrosion cracking tests in a high-temperature water, electrochemical corrosion tests, etc., were performed at hot laboratories. Based on the results obtained, analyses were made on the effects of alloying/impurity elements, irradiation/testing temperatures and material processing, (i.e., post-irradiation annealing and cold working) on the cracking behavior. On the basis of the analyses, possible remedies against IASCC in the core internals were discussed from viewpoints of complex combined effects among materials, environment and processing factors. (author). 156 refs.

  5. The correlation between the dilated extent of bile duct and gallbladder and low bile duct obstructive jaundice diseases

    International Nuclear Information System (INIS)

    Wang Zhongqiu; Lu Guangming; Li Jieshou; Li Weiqin

    2005-01-01

    Objective: To evaluate the diagnostic value about the dilated extent of bile duct and gallbladder in low biliary obstructive diseases. Methods: CT and ERCP findings of 105 patients with low biliary obstructive disease were retrospectively analyzed. The dilated extent of intrahepatic and extra- hepatic bile duct and gallbladder were classified into seven types: Type I: severe dilatation of intrahepatic and extrahepatic bile duct and gallbladder; Type II: severe dilatation of extrahepatic bile duct and gallbladder and slight dilated intrahapetic bile duct; Type III: severe dilatation of intrahepatic and extrahepatic bile duct without or slight dilatation of gallbladder; Type IV: severe extrahepatic bile duct dilatation without or slight dilatation of intrahepatic bile duct and gallbladder; Type V: severe intrahepatic bile duct dilatation without or with slight dilatation of extrahepatic bile duct and gallbladder; Type VI: severe gallbladder dilatation without or with slight intrahepatic and extra- hepatic bile duct dilatation; Type VII: without or with slight dilatation of intrahepatic and extrahepatic bile duct and gallbladder. The biliary system dilated extent of low biliary obstructive disease on CT and ERCP were compared with results of clinical, operation, and pathology. Results: Thirty-three cases of tumor and 72 cases of non-tumor were proved by clinical and operation in 105 patients with low biliary obstructive disease. In 33 tumor patients, 16 patients were identified as Type I, 10 patients Type II, 4 patients Type III, 1 patient Type IV, 2 patients Type VII. In 72 non-tumor patients, 4 patients were identified as Type I, 4 patients Type II, 9 patients Type III, 33 patients Type IV, 2 patients Type V, 11 patients Type VI, 19 patients Type VII. A large difference between I, II type and III-VII type biliary dilatation existed in tumor and non-tumor group (χ 2 =47.33, P<0.01). Conclusion:Low obstructive biliary diseases are closely correlated with the dilated

  6. Corrosion resistant cemented carbide

    International Nuclear Information System (INIS)

    Hong, J.

    1990-01-01

    This paper describes a corrosion resistant cemented carbide composite. It comprises: a granular tungsten carbide phase, a semi-continuous solid solution carbide phase extending closely adjacent at least a portion of the grains of tungsten carbide for enhancing corrosion resistance, and a substantially continuous metal binder phase. The cemented carbide composite consisting essentially of an effective amount of an anti-corrosion additive, from about 4 to about 16 percent by weight metal binder phase, and with the remaining portion being from about 84 to about 96 percent by weight metal carbide wherein the metal carbide consists essentially of from about 4 to about 30 percent by weight of a transition metal carbide or mixtures thereof selected from Group IVB and of the Periodic Table of Elements and from about 70 to about 96 percent tungsten carbide. The metal binder phase consists essentially of nickel and from about 10 to about 25 percent by weight chromium, the effective amount of an anti-corrosion additive being selected from the group consisting essentially of copper, silver, tine and combinations thereof

  7. Corrosion resistant steel

    International Nuclear Information System (INIS)

    Zubchenko, A.S.; Borisov, V.P.; Latyshev, V.B.

    1980-01-01

    Corrosion resistant steel for production of sheets and tubes containing C, Mn, Cr, Si, Fe is suggested. It is alloyed with vanadium and cerium for improving tensile properties and ductility. The steel can be melted by a conventional method in electric-arc or induction furnaces. The mentioned steel is intended to be used as a substitute for nickel-bearing austenitic steels

  8. Corrosion in seawater systems

    International Nuclear Information System (INIS)

    Henrikson, S.

    1988-01-01

    Highly alloyed stainless steels have been exposed to natural chlorinated and chlorine-free seawater at 35 deg. C. Simulated tube-tubesheet joints, weld joints and galvanic couples with titanium, 90/10 CuNi and NiAl bronze were tested and evaluated for corrosion. The corrosion rates of various anode materials - zinc, aluminium and soft iron - were also determined. Finally the risk of hydrogen embrittlement of tubes of ferritic stainless steels and titanium as a consequence of cathodic protection was studied. An attempt was also made to explain the cracking mechanism of the ferritic steels by means of transmission electron microscopy. One important conclusion of the project is that chlorinated seawater is considerably more corrosive to stainless steels than chlorine-free water, whereas chlorination reduces the rate of galvanic corrosion of copper materials coupled to stainless steels. Hydrogen embrittlement of ferritic stainless steels and titanium as a consequence of cathodic protection of carbon steel or cast iron in the same structure can be avoided by strict potentiostatic control of the applied potential. (author)

  9. Corrosion resistant composite materials

    International Nuclear Information System (INIS)

    Ul'yanin, E.A.

    1986-01-01

    Foundations for corrosion-resistant composite materials design are considered with account of components compatibility. Fibrous and lamellar composites with metal matrix, dispersion-hardened steels and alloys, refractory metal carbides-, borides-, nitrides-, silicides-based composites are described. Cermet compositions and fields of their application, such as protective coatings for operation in agressive media at high temperatures, are presented

  10. Isotopes and radiation for modern industry

    International Nuclear Information System (INIS)

    Machi, S.; Yuan, H.C.; Sevastyanov, Y.G.

    1983-01-01

    Brief information is given on the industrial use of isotope and radiation technology in the following fields: radiosterilization of medical supplies, non-destructive testing by radiography, wear and corrosion studies, on-line controls, exploration and recovery of minerals

  11. Corrosion of metal materials embedded in concrete

    International Nuclear Information System (INIS)

    Duffo, G.S.; Farina, S.B.; Schulz, F.M.

    2010-01-01

    Carbon steel is the material most frequently used to strengthen reinforced concrete structures; however, stainless steel and galvanized steel reinforcements are also used in construction concretes; and they are not often used in Latin America. Meanwhile, there are other metals that are embedded in the concrete forming part of the openings (aluminum) or in tubing systems (copper and lead). The use of concrete as a cementing material is also useful for immobilizing wastes, such as for example those generated by the nuclear industry. There is a great deal of research and development on the corrosion of steel reinforcements, but the same is not true for the behavior of other metals embedded in concrete and that also undergo corrosive processes. This work aims to study the corrosion of different metals: copper, lead, aluminum, zinc, stainless steel and carbon steel; embedded in concrete with and without the presence of aggressive species for the metal materials. Test pieces were made of mortar containing rods of different materials for testing, and with chlorides added in concentrations of 0; 0.3 % and 1% (mass of chloride per mass of cement). The test pieces were exposed to different conditions; laboratory environment with a relative humidity (RH) of 45%, a controlled atmosphere with 98% RH and submerged in a solution of 3.5% NaCl. The susceptibility to corrosion of the different metals was evaluated using techniques to monitor the corrosion potential, the resistivity of the mortar and the polarization resistance (PR). The rods were weighed before being placed inside the test pieces to later determine the loss of weight generated by the corrosion process. Polarization curves for the metals were also traced in a simulated pore solution (SPS) and in SPS with added chloride. The results obtained to date show that, of all the metals analyzed, aluminum is the most susceptible to corrosion, and that the test specimens with 0% and 1% of chloride exposed to the laboratory

  12. Smart Coatings for Corrosion Protection

    Science.gov (United States)

    Calle, Luz Marina; Li, Wendy; Buhrow, Jerry W.; Johnsey, Marissa N.

    2016-01-01

    Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. It is essential to detect corrosion when it occurs, and preferably at its early stage, so that action can be taken to avoid structural damage or loss of function. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it.

  13. Effects of explosion-generated shock waves in ducts

    International Nuclear Information System (INIS)

    Busby, M.R.; Kahn, J.E.; Belk, J.P.

    1976-01-01

    An explosion in a space causes an increase in temperature and pressure. To quantify the challenge that will be presented to essential components in a ventilation system, it is necessary to analyze the dynamics of a shock wave generated by an explosion, with attention directed to the propagation of such a wave in a duct. Using the equations of unsteady flow and shock tube theory, a theoretical model has been formulated to provide flow properties behind moving shock waves that have interacted with various changes in duct geometry. Empirical equations have been derived to calculate air pressure, temperature, Mach number, and velocity in a duct following an explosion

  14. Preoperative intraluminal irradiation of the extrahepatic bile duct tumor

    International Nuclear Information System (INIS)

    Kamada, Tadashi; Tsujii, Hirohiko; Arimoto, Takuro; Irie, Goro.

    1991-01-01

    From 1984 through 1986, six patients with extrahepatic bile duct tumor were treated preoperatively with intraluminal irradiation of the bile duct. There were no unresectable cases and pathological examination of the surgical specimens showed moderate to remarkable tumor regression in all cases. Postoperative biliary tract hemorrhage occurred in 2 of 3 patients who received 60 Gy at a point 7.5 mm from the center of the source. With accurate preoperative diagnosis of the tumor extent and careful setting of the target area of intraluminal irradiation, improved local tumor control of extrahepatic bile duct tumor can be expected with this method. (author)

  15. BACTERIOLOGICAL INVESTIGATION ON Fasciola hepatica AND CATTLE BILIARY DUCTS

    Directory of Open Access Journals (Sweden)

    A. Panebianco

    2009-03-01

    Full Text Available The aim of this work was to investigate the occurrence of bacteria in Fasciola hepatica and into cattle biliary ducts containing the parasite. A total of 24 liver and 58 F. hepatica samples were analysed. In all biliary ducts and in 62,06% of parasite Enterobacteriaceae were isolated. The bacterial specie more frequently isolated from parasite were Citrobacter freundii (34%, Proteus mirabilis (18%, Providencia rettgeri (12%, Staphylococcus spp. (18%, Enterobacter spp. (12%. There doesn’t appear to be a correlation between bacterial specie from parasite and ducts. The Authors conclude with some related inspective consideration.

  16. A remote joint system for large vacuum ducts

    International Nuclear Information System (INIS)

    Hagmann, D.B.; Coughlan, J.B.

    1983-01-01

    A large remote vacuum duct joining system has been developed for fusion machines that uses several two-jaw screwdriven clamps. The preferred location for clamp installation is inside the vacuum duct where access space is available for the actuating device. It also decreases space needed for handling operations exterior to the duct. The clamp system is unique in that it is low cost, applies force directly over the seal, permits leak testing to the seal annulus, is highly reliable, can be remotely replaced, and is usable on a variety of other applications

  17. Corrosion potential analysis system

    Science.gov (United States)

    Kiefer, Karl F.

    1998-03-01

    Many cities in the northeastern U.S. transport electrical power from place to place via underground cables, which utilize voltages from 68 kv to 348 kv. These cables are placed in seamless steel pipe to protect the conductors. These buried pipe-type-cables (PTCs) are carefully designed and constantly pressurized with transformer oil to prevent any possible contamination. A protective coating placed on the outside diameter of the pipe during manufacture protects the steel pipe from the soil environment. Notwithstanding the protection mechanisms available, the pipes remain vulnerable to electrochemical corrosion processes. If undetected, corrosion can cause the pipes to leak transformer oil into the environment. These leaks can assume serious proportions due to the constant pressure on the inside of the pipe. A need exists for a detection system that can dynamically monitor the corrosive potential on the length of the pipe and dynamically adjust cathodic protection to counter local and global changes in the cathodic environment surrounding the pipes. The northeastern United States contains approximately 1000 miles of this pipe. This milage is critical to the transportation and distribution of power. So critical, that each of the pipe runs has a redundant double running parallel to it. Invocon, Inc. proposed and tested a technically unique and cost effective solution to detect critical corrosion potential and to communicate that information to a central data collection and analysis location. Invocon's solution utilizes the steel of the casing pipe as a communication medium. Each data gathering station on the pipe can act as a relay for information gathered elsewhere on the pipe. These stations must have 'smart' network configuration algorithms that constantly test various communication paths and determine the best and most power efficient route through which information should flow. Each network station also performs data acquisition and analysis tasks that ultimately

  18. Treatment screening for internal corrosion control of PETROBRAS oil pipelines; Selecao de tratamento para controle da corrosao interna de oleodutos da PETROBRAS

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Cynthia de Azevedo; Muller, Eduardo Gullo [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; Antunes, Warlley Ligorio; Shioya, Nilce Hiromi; Salvador, Angelica Dias [PETROBRAS, RJ (Brazil). Unidade de Negocios da Bacia de Campos

    2005-07-01

    The use of corrosion inhibitors is spread out in oil and gas industry and is the most common methodology to control pipeline internal corrosion. However, their effectiveness depends on the pipeline material, inhibitor composition, flow type and scale characteristics. When a pipeline has heavy scale deposits, thick bacterial biofilm, or oxygen contamination, the corrosion control via filmic inhibitors is not effective. So, the only way to control internal corrosion of an oil pipeline is to primary identifies the corrosive agent and the main corrosion mechanism. The monitoring of the inhibitor efficiency and the determination of minimal residual concentration to prevent corrosion, are also fundamental. In this paper, is presented the criteria used to identify the main corrosion mechanism of oil pipelines, the treatment proposed in each case and the techniques employed in real time corrosion monitoring. (author)

  19. Mobile evaporator corrosion test results

    International Nuclear Information System (INIS)

    Rozeveld, A.; Chamberlain, D.B.

    1997-05-01

    Laboratory corrosion tests were conducted on eight candidates to select a durable and cost-effective alloy for use in mobile evaporators to process radioactive waste solutions. Based on an extensive literature survey of corrosion data, three stainless steel alloys (304L, 316L, AL-6XN), four nickel-based alloys (825, 625, 690, G-30), and titanium were selected for testing. The corrosion tests included vapor phase, liquid junction (interface), liquid immersion, and crevice corrosion tests on plain and welded samples of candidate materials. Tests were conducted at 80 degrees C for 45 days in two different test solutions: a nitric acid solution. to simulate evaporator conditions during the processing of the cesium ion-exchange eluant and a highly alkaline sodium hydroxide solution to simulate the composition of Tank 241-AW-101 during evaporation. All of the alloys exhibited excellent corrosion resistance in the alkaline test solution. Corrosion rates were very low and localized corrosion was not observed. Results from the nitric acid tests showed that only 316L stainless steel did not meet our performance criteria. The 316L welded interface and crevice specimens had rates of 22.2 mpy and 21.8 mpy, respectively, which exceeds the maximum corrosion rate of 20 mpy. The other welded samples had about the same corrosion resistance as the plain samples. None of the welded samples showed preferential weld or heat-affected zone (HAZ) attack. Vapor corrosion was negligible for all alloys. All of the alloys except 316L exhibited either open-quotes satisfactoryclose quotes (2-20 mpy) or open-quotes excellentclose quotes (<2 mpy) corrosion resistance as defined by National Association of Corrosion Engineers. However, many of the alloys experienced intergranular corrosion in the nitric acid test solution, which could indicate a susceptibility to stress corrosion cracking (SCC) in this environment

  20. Bio-corrosion of water pipeline by sulphate-reducing bacteria in a ...

    African Journals Online (AJOL)

    esiri

    2013-11-13

    Nov 13, 2013 ... Key words: Sulphate-reducing bacteria, corrosion, water pipeline, biocide. INTRODUCTION ... small amount of organic material required to produce biomass):. )1(. 3. 2 .... Oil, gas and shipping industries are seriously affected.

  1. Hydrostatic bearing with a stepped duct

    International Nuclear Information System (INIS)

    Krevsun, Eh.P.; Ivanov, A.A.

    1975-01-01

    A method for calculating and experimental data from tests on a hydrostatic bearing whose operating hydraulic channel is formed by two cylincrical surfaces, are presented. Unlike currently used hydrostatic bearings, the bearing described has no capillary choke or diaphragm choke at the entrance. This simplifies the construction and increases the reliability, especially when it is operated with corrosive liquids or liquids containing solid suspensoids and causing erosion and blockage of the choke structures. In order to obtain the calculated relations, the flow of a liquid from the bearing in the axial direction to one side through a part of an aperture of unit width was examined. The effect of rotating the axle, of flow in the circumferential direction, and curvature of the aperture was not considered. Isothermal and laminar flows were considered. Because of the simplicity of the hydraulic circuit and the satisfactory properties (bearing capability and flow rate), the bearing described may be used in pumps operating with corrosive liquids, with those containing solid suspensoids and in nuclear energy establishments. (author)

  2. Online monitoring of corrosion behavior in molten metal using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Zeng, Qiang; Pan, Congyuan; Li, Chaoyang; Fei, Teng; Ding, Xiaokang; Du, Xuewei; Wang, Qiuping

    2018-04-01

    The corrosion behavior of structure materials in direct contact with molten metals is widespread in metallurgical industry. The corrosion of casting equipment by molten metals is detrimental to the production process, and the corroded materials can also contaminate the metals being produced. Conventional methods for studying the corrosion behavior by molten metal are offline. This work explored the application of laser-induced breakdown spectroscopy (LIBS) for online monitoring of the corrosion behavior of molten metal. The compositional changes of molten aluminum in crucibles made of 304 stainless steel were obtained online at 1000 °C. Several offline techniques were combined to determine the corrosion mechanism, which was highly consistent with previous studies. Results proved that LIBS was an efficient method to study the corrosion mechanism of solid materials in molten metal.

  3. Bile Duct Cancer (Cholangiocarcinoma) Treatment (PDQ®)—Health Professional Version

    Science.gov (United States)

    Bile duct cancer (also called cholangiocarcinoma) can occur in the bile ducts in the liver (intrahepatic) or outside the liver (perihilar or distal extrahepatic). Learn about the types of bile duct cancer, risk factors, clinical features, staging, and treatment for bile duct cancer in this expert-reviewed summary.

  4. Bile Duct Cancer (Cholangiocarcinoma) Symptoms, Tests, Prognosis, and Stages (PDQ®)—Patient Version

    Science.gov (United States)

    Bile duct cancer, or cholangiocarcinoma, is rare. Bile ducts are tubes that carry bile between the liver, gallbladder, and small intestine. Bile duct cancer can occur in the intrahepatic, perihilar (Klatskin tumor), or distal extrahepatic area. Learn about tests to diagnose and the stages of bile duct cancer.

  5. Effect of mechanical treatment on intergranular corrosion of 6064 alloy bars

    Science.gov (United States)

    Sláma, P.; Nacházel, J.

    2017-02-01

    Aluminium Al-Mg-Si-type alloys (6xxx-series) exhibit good mechanical properties, formability, weldability and good corrosion resistance in various environments. They often find use in automotive industry and other applications. Some alloys, however, particularly those with higher copper levels, show increased susceptibility to intergranular corrosion. Intergranular corrosion (IGC) is typically related to the formation of microgalvanic cells between cathodic, more noble phases and depleted (precipitate-free) zones along grain boundaries. It is encountered mainly in AlMgSi alloys containing Cu, where it is thought to be related to the formation Q-phase precipitates (Al4Mg8Si7Cu2) along grain boundaries. The present paper describes the effects of mechanical working (extrusion, drawing and straightening) and artificial aging on intergranular corrosion in rods of the 6064 alloy. The resistance to intergranular corrosion was mapped using corrosion tests according to EN ISO 11846, method B. Corrosion tests showed dependence of corrosion type on mechanical processing of the material. Intergranular, pitting and transgranular corrosion was observed. Artificial ageing influenced mainly the depth of the corrosion.

  6. ß-adrenergic regulation of ion transport in pancreatic ducts: Patch-clamp study of isolated rat pancreatic ducts

    DEFF Research Database (Denmark)

    Novak, I

    1998-01-01

    BACKGROUND & AIMS: In the intact pancreas, bicarbonate secretion is thought to be controlled by a number of regulators, including adrenergic agonists. The aim of this study was to investigate the effects of adrenergic agonists on pancreatic ducts, which are the site of bicarbonate secretion....... METHODS: Small intralobular ducts were isolated from rat pancreas and studied in vitro by the whole-cell patch clamp technique. Cell membrane voltages and currents were indicators of cellular ion transport. In some ducts, intracellular Ca2+ activity was measured by fluorescence optical methods. RESULTS...

  7. Studi Eksperimen Aliran Melalui Square Duct dan Square Elbow 90º dengan Double Guide Vane pada Variasi Sudut Bukaan Damper

    Directory of Open Access Journals (Sweden)

    Andrew Jaya Nazar

    2017-01-01

    Full Text Available Instalasi saluran udara tidak hanya berupa pipa lurus, tetapi juga terdapat fitting/aksesoris perpipaan misalnya elbow 90o dan damper. Aksesoris perpipaan ini berfungsi agar saluran udara dapat terpasang sesuai dengan kebutuhan. Namun, penggunaan aksesoris perpipaan ini menyebabkan bertambahnya pressure drop akibat adanya friction loss dan separation loss. Pemasangan guide vane pada elbow 90o diharapkan dapat mengurangi pressure drop karena dapat mengurangi terjadinya secondary flow, namun hal ini dapat menambah kerugian akibat gaya gesek. Saat ini penghematan energi menjadi sorotan terutama dalam dunia industri. Penurunan pressure drop pada belokan perpipaan sangat diharapkan, agar dapat menghemat energi lebih. Untuk itu perlu dilakukan usaha agar dapat menurunkan pressure drop yang terjadi. Penelitian ini dilakukan secara eksperimen dengan benda uji saluran udara yang terdiri dari: upstream duct (straight duct, square elbow 90o dengan r/Dh=1,5 dan dilengkapi double guide vane, damper, downstream duct (straight duct, dan induced fan. Pengukuran parameter yang dibutuhkan dilakukan dengan menggunakan: pitot tube, inclined manometer, pressure tranducer. Dari eksperimen ini diperoleh bahwa profil kecepatan pada masing-masing variasi sudut bukaan damper sudah mendekati keadaan recovery aliran pada akhir section baik dari bidang vertikal maupun horizontal. Pressure drop yang terjadi semakin naik seiring dengan bertambahnya nilai bilangan Reynolds dan sudut bukaan damper. Nilai konstanta damper semakin naik dari bukaan sudut 0o hingga 30o.

  8. Direct growth of cerium oxide nanorods on diverse substrates for superhydrophobicity and corrosion resistance

    Science.gov (United States)

    Cho, Young Jun; Jang, Hanmin; Lee, Kwan-Soo; Kim, Dong Rip

    2015-06-01

    Superhydrophobic surfaces with anti-corrosion properties have attracted great interest in many industrial fields, particularly to enhance the thermal performance of offshore applications such as heat exchangers, pipelines, power plants, and platform structures. Nanostructures with hydrophobic materials have been widely utilized to realize superhydrophobicity of surfaces, and cerium oxide has been highlighted due to its good corrosion resistive and intrinsically hydrophobic properties. However, few studies of direct growth of cerium oxide nanostructures on diverse substrates have been reported. Herein we report a facile hydrothermal method to directly grow cerium oxide nanorods on diverse substrates, such as aluminum alloy, stainless steel, titanium, and silicon. Diverse substrates with cerium oxide nanorods exhibited superhydrophobicity with no hydrophobic modifiers on their surfaces, and showed good corrosion resistive properties in corrosive medium. We believe our method could pave the way for realization of scalable and sustainable corrosion resistive superhydrophobic surfaces in many industrial fields.

  9. Natural Corrosion Inhibitors for Steel Reinforcement in Concrete — a Review

    Science.gov (United States)

    Raja, Pandian Bothi; Ghoreishiamiri, Seyedmojtaba; Ismail, Mohammad

    2015-04-01

    Reinforced concrete is one of the widely used construction materials for bridges, buildings, platforms and tunnels. Though reinforced concrete is capable of withstanding a large range of severe environments including marine, industrial and alpine conditions, there are still a large number of failures in concrete structures for many reasons. Either carbonation or chloride attack is the main culprit which is due to depassivation of reinforced steel and subsequently leads to rapid steel corrosion. Among many corrosion prevention measures, application of corrosion inhibitors play a vital role in metal protection. Numerous range of corrosion inhibitors were reported for concrete protection that were also used commercially in industries. This review summarizes the application of natural products as corrosion inhibitors for concrete protection and also scrutinizes various factors influencing its applicability.

  10. Status of the development of hot gas ducts for HTRs

    International Nuclear Information System (INIS)

    Stehle, H.; Klas, E.

    1984-01-01

    In the PNP nuclear process heat system the heat generated in the helium cooled core is transferred to the steam reformer and to the successive steam generator or to the intermediate heat exchanger by the primary helium via suitable hot gas ducts. The heat is carried over to the steam gasifier by the intermediate heat exchanger and a secondary helium loop. In both the primary and the secondary loop, the hot gas ducts are internally insulated by a ceramic fibre insulation to protect the support tube and the pressure housing from the high helium temperatures. A graphite hot gas liner will be used for the coaxial primary duct with an annular gap between support tube and pressure shell for the cold gas counterflow. A metallic hot gas liner will be installed in the secondary duct

  11. Improvement in the management of bile duct injuries?

    NARCIS (Netherlands)

    Keulemans, Y. C.; Bergman, J. J.; de Wit, L. T.; Rauws, E. A.; Huibregtse, K.; Tytgat, G. N.; Gouma, D. J.

    1998-01-01

    BACKGROUND: Previous studies have suggested that improvements in diagnostic workup and treatment of bile duct injuries (BDI) sustained during laparoscopic cholecystectomy can be expected as experience increases with the laparoscopic procedure. Many published articles reported that early diagnosis,

  12. Design requirement on KALIMER control rod assembly duct

    International Nuclear Information System (INIS)

    Hwang, W.; Kang, H. Y.; Nam, C.; Kim, J. O.; Kim, Y. J.

    1998-03-01

    This document establishes the design guidelines which are needs for designing the control rod assembly duct of the KALIMER as design requirements. it describes control rod assembly duct of the KALIMER and its requirements that includes functional requirements, performance requirements, interfacing systems, design limits and strength requirements, seismic requirements, structural requirements, environmental requirements, reliability and safety requirements, standard and codes, QA programs, and other requirements. The control rod system consists of three parts, which are drive mechanism, drive-line, and absorber bundle. This report deals with the absorber bundle and its outer duct only because the others are beyond the scope of fuel system design. The guidelines for design requirements intend to be used for an improved design of the control rod assembly duct of the KALIMER. (author). 19 refs

  13. Intraductal papillary neoplasm of the bile duct: a case report.

    Science.gov (United States)

    Peeters, Karen; Delvaux, Peter; Huysentruyt, Frederik

    2017-08-01

    Intraductal papillary neoplasm of the bile duct (IPNB) is a rare variant of bile duct tumors, characterized by papillary growth within the bile duct lumen and is regarded as a biliary counterpart of intraductal papillary mucinous neoplasm (IPMN) of the pancreas. IPNBs are mainly found in patients from Far Eastern areas, where hepatolithiasis and clonorchiasis are endemic. The Western experience, however, remains limited. In this article, we report a 56-year-old man, referred to our hospital because of deranged liver function tests. Further imaging modalities showed a cystic lesion of 9 cm diameter, arising from the left hepatic duct. Inlying was a heterogeneous, lobulated mass. The patient underwent a left hemihepatectomy and adjuvant chemotherapy. Despite recent advanced technologies, diagnosis of IPNB is still challenging, especially in western countries due to its rarity. Early identification and resection of lesions, even in asymptomatic or minimally symptomatic patients, are however important prognostic factors.

  14. Design requirement on KALIMER control rod assembly duct

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, W.; Kang, H. Y.; Nam, C.; Kim, J. O.; Kim, Y. J

    1998-03-01

    This document establishes the design guidelines which are needs for designing the control rod assembly duct of the KALIMER as design requirements. it describes control rod assembly duct of the KALIMER and its requirements that includes functional requirements, performance requirements, interfacing systems, design limits and strength requirements, seismic requirements, structural requirements, environmental requirements, reliability and safety requirements, standard and codes, QA programs, and other requirements. The control rod system consists of three parts, which are drive mechanism, drive-line, and absorber bundle. This report deals with the absorber bundle and its outer duct only because the others are beyond the scope of fuel system design. The guidelines for design requirements intend to be used for an improved design of the control rod assembly duct of the KALIMER. (author). 19 refs.

  15. Spontaneous common bile duct perforation—A rare clinical entity

    Directory of Open Access Journals (Sweden)

    Melissa Amberger

    Full Text Available Introduction: Spontaneous common bile duct perforation is an uncommon clinical entity in both adults and children. Few case reports have been published since the first clinical description in 1882. Our work has been reported in line with SCARE criteria. Presentation of case: Herein, we describe the case of a 28 year-old female who suffered spontaneous common bile duct perforation while admitted for choledocholithiasis. Discussion: The perforation occurred while in-hospital, and extensive imaging and laboratory tests characterized the disease in detail. To our knowledge, this is the first report of spontaneous common bile duct perforation witnessed from pre-perforation through definitive management. Conclusion: Physicians and Surgeons should seek out this uncommon diagnosis in the patient with suspected Choledocholithiasis who suddenly become peritoneal on physical exam so that definitive care can be expedited. Keywords: Common bile duct, Biliary peritonitis, Choledocholithiasis

  16. Heuristic approach to the passive optical network with fibre duct ...

    African Journals Online (AJOL)

    Integer programming, network flow optimisation, passive optical network, ... This paper uses concepts from network flow optimisation to incorporate fibre duct shar ... [4] studied the survivable constrained ConFL problem and solved a number of.

  17. Corrosion Evaluation and Corrosion Control of Steam Generators

    International Nuclear Information System (INIS)

    Maeng, W. Y.; Kim, U. C.; Sung, K. W.; Na, J. W.; Lee, Y. H.; Lee, D. H.; Kim, K. M.

    2008-06-01

    Corrosion damage significantly influences the integrity and efficiency of steam generator. Corrosion problems of steam generator are unsolved issues until now even though much effort is made around world. Especially the stress corrosion cracking of heat exchange materials is the first issue to be solved. The corrosion protection method of steam generator is important and urgent for the guarantee of nuclear plant's integrity. The objectives of this study are 1) to evaluate the corrosion properties of steam generator materials, 2) to optimize the water chemistry of steam generator and 3) to develop the corrosion protection method of primary and secondary sides of steam generator. The results will be reflected to the water chemistry guideline for improving the integrity and efficiency of steam generator in domestic power plants

  18. Corrosion Evaluation and Corrosion Control of Steam Generators

    Energy Technology Data Exchange (ETDEWEB)

    Maeng, W. Y.; Kim, U. C.; Sung, K. W.; Na, J. W.; Lee, Y. H.; Lee, D. H.; Kim, K. M

    2008-06-15

    Corrosion damage significantly influences the integrity and efficiency of steam generator. Corrosion problems of steam generator are unsolved issues until now even though much effort is made around world. Especially the stress corrosion cracking of heat exchange materials is the first issue to be solved. The corrosion protection method of steam generator is important and urgent for the guarantee of nuclear plant's integrity. The objectives of this study are 1) to evaluate the corrosion properties of steam generator materials, 2) to optimize the water chemistry of steam generator and 3) to develop the corrosion protection method of primary and secondary sides of steam generator. The results will be reflected to the water chemistry guideline for improving the integrity and efficiency of steam generator in domestic power plants.

  19. Fuzzy logic and modeling of ventilation networks in the nuclear industry; Logique floue et modelisation des reseaux de ventilation dans l'industrie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Floquet, P.; Lhoste, J.C.; Domenech, S.; Pibouleau, L. [Ecole Nationale Superieure des Arts Chimiques et Technologiques, Lab. de Genie Chimique, LGC, UMR CNRS/INP/UPS 5503, 31 - Toulouse (France); Laborde, J.C. [CEA Saclay, Institut de la Protection et de la Surete Nucleaire, IPSN, DPEA/SERAC, 91 - Gif-sur-Yvette (France)

    2001-07-01

    This article presents the implementation of fuzzy logic in the modeling of ducts, filters and pressures of the ventilation networks of the nuclear industry, taking into account the uncertainties of the aeraulic parameters. (J.S.)

  20. SULFURIC ACID CORROSION OF LOW Sb - Pb BATTERY ALLOYS

    African Journals Online (AJOL)

    user

    1983-09-01

    Sep 1, 1983 ... (Manuscript received February,1983). ABSTRACT. The corrosion properties of low Sb - Pb alloys developed for maintenance free motive power industrial batteries was studied by a bare grid constant current method and compared to those of the conventional. Pb- 6% Sb alloy. Low Sb-Pb alloys with Se and ...