WorldWideScience

Sample records for solution spray leak

  1. Radiological and toxicological consequences of a worst-case spray leak related to project W-320

    International Nuclear Information System (INIS)

    Himes, D.A.

    1997-01-01

    An analysis was performed of radiological and toxicological consequences of a worst-case leak from a 2-inch diameter flush connection in a pit over tank AY-102. The unmitigated (without controls) flush line spray leak assumes that the blank connector and the removable plug in the pit cover block have been removed so that the maximum system flow is directed out of the open 2-inch line vertically into the air above the pit. The mitigated (with controls) spray scenario assumes the removable plug is in place and the flow is directed against the underside of the pit cover block. The unmitigated scenario exceeded both onsite and offsite risk guidelines for an anticipated accident. For the mitigated case all consequences are well within guidelines and so no additional controls are needed beyond the existing control of having all pit covers and removable plugs in place during any waste transfer

  2. Radiolysis of spray solutions

    International Nuclear Information System (INIS)

    Habersbergerova, A.; Janovsky, I.

    1985-01-01

    The factors were studied affecting thiosulfate radiolysis in the so-called spray solution for nuclear power plant containments. The reaction mechanism of primary radiolytic reactions leading to thiosulfate decomposition was studied using pulse radiolysis. Also measured was hydrazine loss in the irradiation of the bubbling solution intended for the capture of volatile chemical forms of radioiodine. Pulse radiolysis was used to study the kinetics of hydrazine reaction with elemental iodine. (author)

  3. Direct spraying method for fabrication of paper-based microfluidic devices

    International Nuclear Information System (INIS)

    Liu, Ning; An, Hong-Jie; Lew, Wen Siang; Xu, Jing; Phan, Dinh-Tuan; Hashimoto, Michinao

    2017-01-01

    Direct spraying of hydrophobic materials is an affordable, easy-to-use and equipment-free method for fabrication of flexible microsensors, albeit not yet widely adopted. To explore its application potential, in this paper, we propose and demonstrate two novel hybrid methods to fabricate paper-based components. Firstly, through combing direct spraying with Parafilm embedding, a leak-free paper-based sample preconcentrator for fluorescence sensing was fabricated. The leak-free device worked on the principle of ion concentration polarization (ICP) effect, and achieved enhancement of fluorescent tracer by 220 folds on a paper substrate. Secondly, by using the sprayed hydrophobic patterns, paper-based microsized supercapacitors (mSCs) were fabricated. Vacuum filtration was used to deposit multi-wall carbon nanotubes (MWCNT)-dispersed solution on a porous substrate to form electrodes. A volumetric capacitance of 42.5 mF cm −3 at a current density of 2 mA cm −3 was obtained on the paper-based mSC. Our demonstrations have shown the versatility of direct spraying for the fabrication of integrative paper-based microfluidic devices. (paper)

  4. Mitigated Transfer Line Leaks that Result in Surface Pools and Spray Leaks into Pits

    Energy Technology Data Exchange (ETDEWEB)

    HEY, B.E.

    1999-12-07

    This analysis provides radiological and toxicological consequence calculations for postulated mitigated leaks during transfers of six waste compositions. Leaks in Cleanout Boxes equipped with supplemental covers and leaks in pits are analyzed.

  5. Mitigated Transfer Line Leaks that Result in Surface Pools and Spray Leaks into Pits

    International Nuclear Information System (INIS)

    HEY, B.E.

    1999-01-01

    This analysis provides radiological and toxicological consequence calculations for postulated mitigated leaks during transfers of six waste compositions. Leaks in Cleanout Boxes equipped with supplemental covers and leaks in pits are analyzed

  6. Helium leak testing of scanning electron microscope

    International Nuclear Information System (INIS)

    Ahmad, Anis; Tripathi, S.K.; Mukherjee, D.

    2015-01-01

    Scanning Electron Microscope (SEM) is a specialized electron-optical device which is used for imaging of miniscule features on topography of material specimens. Conventional SEMs used finely focused high energy (about 30 KeV) electron beam probes of diameter of about 10nm for imaging of solid conducting specimens. Vacuum of the order of 10"-"5 Torr is prerequisite for conventional Tungsten filament type SEMs. One such SEM was received from one of our laboratory in BARC with a major leak owing to persisting poor vacuum condition despite continuous pumping for several hours. He-Leak Detection of the SEM was carried out at AFD using vacuum spray Technique and various potential leak joints numbering more than fifty were helium leak tested. The major leak was detected in the TMP damper bellow. The part was later replaced and the repeat helium leak testing of the system was carried out using vacuum spray technique. The vacuum in SEM is achieved is better than 10"-"5 torr and system is now working satisfactorily. (author)

  7. Production of amorphous starch powders by solution spray drying

    NARCIS (Netherlands)

    Niazi, Muhammad B. K.; Broekhuis, Antonius A.

    2012-01-01

    The spray drying of starch/maltodextrin formulations was evaluated as a potential technology for the manufacturing of amorphous thermoplastic starches. Mixtures of starches with high to low amylose (Am)amylopectin (Ap) ratios were spray-dried from water-based solutions and granular dispersions. The

  8. Leak testing of cryogenic components — problems and solutions

    Science.gov (United States)

    Srivastava, S. P.; Pandarkar, S. P.; Unni, T. G.; Sinha, A. K.; Mahajan, K.; Suthar, R. L.

    2008-05-01

    moderator pot was driving the MSLD out of range. Since it was very difficult to locate the leak by Tracer Probe Method, some other technique was ventured to solve the problem of leak location. Finally, it was possible to locate the leak by observing the change in Helium background reading of MSLD during masking/unmasking of the welded joints. This paper, in general describes the design and leak testing aspects of cryogenic components of Cold Neutron Source and in particular, the problems and solutions for leak testing of transfer lines and moderator pot.

  9. Spray drying test of simulated borated waste solutions

    International Nuclear Information System (INIS)

    An Hongxiang; Zhou Lianquan; Fan Zhiwen; Sun Qi; Lin Xiaolong

    2007-01-01

    Performance and the effecting factors of spray drying of simulated borated waste solutions is studied for three contaeting methods between the atomized beads and the heated air, in which boron concentration is around 21000 ppm. The contacting modes are centrifugal atomizing co-current flow, pneumatic atomizing co-current flow and mixed flow. The results show that a free-flowing product in all these tests when the temperature of the solutions is between 62 degree C and 64 degree C, the inlet temperature of the spray drying chamber is between 210 degree C and 220 degree C, the temperature of the outlet of the spray drying chamber is between 110 and 120 degree C, the flow rate of the pressure air is 8.0 m 3 /h, the rotational speed of the centrifugal atomizer is 73.0 m/s. The diameters of the powder product which account for 95% of the feed range from 0.356 mm to 0.061 mm. The production capacity and water content in the powder increase in the order of pneumatic atomizing co-current flow, mixed flow and centrifugal atomizing co-current flow. The volume reduction coeffecient of spray drying is in the ranged of 0.22 and 0.27. (authors)

  10. Current Progress in Solution Precursor Plasma Spraying of Cermets: A Review

    Directory of Open Access Journals (Sweden)

    Romnick Unabia

    2018-06-01

    Full Text Available Ceramic and metal composites, known also as cermets, may considerably improve many material properties with regards to that of initial components. Hence, cermets are frequently applied in many technological fields. Among many processes which can be employed for cermet manufacturing, thermal spraying is one of the most frequently used. Conventional plasma spraying of powders is a popular and cost-effective manufacturing process. One of its most recent innovations, called solution precursor plasma spraying (SPPS, is an emerging coating deposition method which uses homogeneously mixed solution precursors as a feedstock. The technique enables a single-step deposition avoiding the powder preparation procedures. The nanostructured coatings developed by SPPS increasingly find a place in the field of surface engineering. The present review shows the recent progress in the fabrication of cermets using SPPS. The influence of starting solution precursors, such as their chemistry, concentration, and solvents used, to the micro-structural characteristics of cermet coatings is discussed. The effect of the operational plasma spray process parameters such as solution injection mode to the deposition process and coatings’ microstructure is also presented. Moreover, the advantages of the SPPS process and its drawbacks compared to the conventional powder plasma spraying process are discussed. Finally, some applications of SPPS cermet coatings are presented to understand the potential of the process.

  11. Standard specification for leak detector solutions intended for use on brasses and other copper alloys

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This specification covers the requirements for leak detector solutions suitable for use in checking the leakage of valves, pipes, fittings, joints, and so forth of a pressurized gas system fabricated from brasses and other copper alloys. 1.2 This specification deals with the stress corrosion cracking aspect of leak detector solutions. The effectiveness, chemical, physical and mechanical properties of leak detector solutions are not within the scope of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.

  12. Development of design solutions for spray ponds

    International Nuclear Information System (INIS)

    Omel'chenko, M.P.; Minasyan, R.G.; Kranzfeld, Ja.L.; Zaruba, V.C.; Baranov, Yu.A.; Sorokin, M.Ja.; Jegorov, A.V.; Khashchina, M.V.

    1990-01-01

    The principles of process design of spray cooling systems for responsible consumers of up-to-date reactor building are discussed in this paper. Development in design principles with respect to problem solving of operational reliability increase and ecological efficiency of nuclear power equipment is shown. The structural solutions of basin antifiltration shield are spoken in detail. The results of experimental physical-mathematical and climatic studies as well as comparative tests of bituminous asphalt emulsive mastic and mushy asphalt are reported. The directions of up-to-date researches on improvement of concept of spray coolers are indicated

  13. Electrochemical performance of solid oxide fuel cells having electrolytes made by suspension and solution precursor plasma spraying

    Science.gov (United States)

    Marr, M.; Kuhn, J.; Metcalfe, C.; Harris, J.; Kesler, O.

    2014-01-01

    Yttria-stabilized zirconia (YSZ) electrolytes were deposited by suspension plasma spraying (SPS) and solution precursor plasma spraying (SPPS). The electrolytes were evaluated for permeability, microstructure, and electrochemical performance. With SPS, three different suspensions were tested to explore the influence of powder size distribution and liquid properties. Electrolytes made from suspensions of a powder with d50 = 2.6 μm were more gas-tight than those made from suspensions of a powder with d50 = 0.6 μm. A peak open circuit voltage of 1.00 V was measured at 750 °C with a cell with an electrolyte made from a suspension of d50 = 2.6 μm powder. The use of a flammable suspension liquid was beneficial for improving electrolyte conductivity when using lower energy plasmas, but the choice of liquid was less important when using higher energy plasmas. With SPPS, peak electrolyte conductivities were comparable to the peak conductivities of the SPS electrolytes. However, leak rates through the SPPS electrolytes were higher than those through the electrolytes made from suspensions of d50 = 2.6 μm powder. The electrochemical test data on SPPS electrolytes are the first reported in the literature.

  14. Spatio-temporal droplet size statistics in developing spray of starchy solution

    Science.gov (United States)

    Naz, Muhammad Yasin; Sulaiman, Shaharin Anwar; Ariwahjoedi, Bambang

    2015-07-01

    In the given research, the spray jet breakup of a modified starch solution was studied as a function of jet injection time and nozzle orifice diameter. The starch-urea-borax solution was prepared and tested with three axisymmetric full cone nozzles at service temperature of 80°C and the injection pressure of 5 bar. It is worth mentioning that no jet breakup was seen below these temperature and pressure values. The imaging studies on the time based spray evolution revealed monotonic increase in both; spray cone angle and tip penetration with an increase in injection time form 0-300 mm. Hereinafter, both parameters exhibited constants value over injection time. Phase Doppler Anemometry (PDA) measurements of the droplet size revealed significant decrease in the Sauter Mean Diameter (SMD) along the spray centerline. However, a steady decrease in SMD was seen towards the spray boundary. For fixed injection time of 300 ms, the overall SMD was decreased from 112 to 71 µm at 60 mm downstream, from 102 to 64 µm at 100 mm downstream and from 85 to 61 µm at 140 mm downstream with an increase in orifice diameter from 1.19 to 1.59 mm.

  15. Evaluation of sprayed hypochlorous acid solutions for their virucidal activity against avian influenza virus through in vitro experiments

    Science.gov (United States)

    HAKIM, Hakimullah; THAMMAKARN, Chanathip; SUGURO, Atsushi; ISHIDA, Yuki; KAWAMURA, Akinobu; TAMURA, Miho; SATOH, Keisuke; TSUJIMURA, Misato; HASEGAWA, Tomomi; TAKEHARA, Kazuaki

    2014-01-01

    Hypochlorous acid (HOCl) solutions were evaluated for their virucidal ability against a low pathogenic avian influenza virus (AIV), H7N1. HOCl solutions containing 50, 100 and 200 ppm chlorine (pH 6) or their sprayed solutions (harvested in dishes placed at 1 or 30 cm distance between the spray nozzle and dish) were mixed with the virus with or without organic materials (5% fetal bovine serum: FBS). Under plain diluent conditions (without FBS), harvested solutions of HOCl after spraying could decrease the AIV titer by more than 1,000 times, to an undetectable level (< 2.5 log10TCID50/ml) within 5 sec, with the exception of the 50 ppm solution harvested after spraying at the distance of 30 cm. Under the dirty conditions (in the presence of 5% FBS), they lost their virucidal activity. When HOCl solutions were sprayed directly on the virus on rayon sheets for 10 sec, the solutions of 100 and 200 ppm could inactivate AIV immediately after spraying, while 50 ppm solution required at least 3 min of contact time. In the indirect spray form, after 10 sec of spraying, the lids of the dishes were opened to expose the virus on rayon sheets to HOCl. In this form, the 200 ppm solution inactivated AIV within 10 min of contact, while 50 and 100 ppm could not inactivate it. These data suggest that HOCl can be used in spray form to inactivate AIV at the farm level. PMID:25421399

  16. Evaluation of sprayed hypochlorous acid solutions for their virucidal activity against avian influenza virus through in vitro experiments.

    Science.gov (United States)

    Hakim, Hakimullah; Thammakarn, Chanathip; Suguro, Atsushi; Ishida, Yuki; Kawamura, Akinobu; Tamura, Miho; Satoh, Keisuke; Tsujimura, Misato; Hasegawa, Tomomi; Takehara, Kazuaki

    2015-02-01

    Hypochlorous acid (HOCl) solutions were evaluated for their virucidal ability against a low pathogenic avian influenza virus (AIV), H7N1. HOCl solutions containing 50, 100 and 200 ppm chlorine (pH 6) or their sprayed solutions (harvested in dishes placed at 1 or 30 cm distance between the spray nozzle and dish) were mixed with the virus with or without organic materials (5% fetal bovine serum: FBS). Under plain diluent conditions (without FBS), harvested solutions of HOCl after spraying could decrease the AIV titer by more than 1,000 times, to an undetectable level (< 2.5 log10TCID50/ml) within 5 sec, with the exception of the 50 ppm solution harvested after spraying at the distance of 30 cm. Under the dirty conditions (in the presence of 5% FBS), they lost their virucidal activity. When HOCl solutions were sprayed directly on the virus on rayon sheets for 10 sec, the solutions of 100 and 200 ppm could inactivate AIV immediately after spraying, while 50 ppm solution required at least 3 min of contact time. In the indirect spray form, after 10 sec of spraying, the lids of the dishes were opened to expose the virus on rayon sheets to HOCl. In this form, the 200 ppm solution inactivated AIV within 10 min of contact, while 50 and 100 ppm could not inactivate it. These data suggest that HOCl can be used in spray form to inactivate AIV at the farm level.

  17. On the helium gas leak test

    International Nuclear Information System (INIS)

    Nishikawa, Akira; Ozaki, Susumu

    1975-01-01

    The helium gas leak test (Helium mass spectrometer testing) has a leak detection capacity of the highest level in practical leak tests and is going to be widely applied to high pressure vessels, atomic and vacuum equipments that require high tightness. To establish a standard test procedure several series of experiments were conducted and the results were investigated. The conclusions are summarized as follows: (1) The hood method is quantitatively the most reliable method. The leak rate obtained by tests using 100% helium concentration should be the basis of the other method of test. (2) The integrating method, bell jar method, and vacuum spray method can be considered quantitative when particular conditions are satisfied. (3) The sniffer method is not to be considered quantitive. (4) The leak rate of the hood, integrating, and bell jar methods is approximately proportional to the square of the helium partial pressure. (auth.)

  18. Aerial spraying to capture released radioactivity from NPP in a severe accident

    International Nuclear Information System (INIS)

    Younus, Irfan; Yim, Man Sung; Medard, Thiphaine

    2016-01-01

    The proposed strategy in this paper is the use of aqueous spray (water/foam) mixed with suitable chemical additives to capture, dissolve and stabilize the radioactive gases and aerosol particles released from leaked reactor containment and auxiliary building. The spray system can be approached to the leaked reactor building through the use of a truck with high rising cranes, unmanned aerial vehicles (UAVs, such as helicopters), aerostats, or by installing fixed piping structure around the containment building depending on the accident situation. Laboratory-scale experimental system was setup to examine the performance of such systems. The alkaline water (aqueous NaOH.Na_2S_2O_3) and foam-based spray material (sodium lauryl sulphate) were used to examine capture efficiency of gaseous iodine and aerosol particles. The gaseous iodine and aerosol removal efficiency of foam-based spray is higher when compared with alkaline water-based spray. 2. The nozzle producing full cone spray provides the better removal efficiency than nozzle producing hollow cone spray patterns.

  19. Effect of the borax mass and pre-spray medium temperature on droplet size and velocity vector distributions of intermittently sprayed starchy solutions.

    Science.gov (United States)

    Naz, Muhammad Yasin; Sulaiman, Shaharin Anwar; Ariwahjoedi, Bambang

    2015-02-07

    Spray coating technology has demonstrated great potential in the slow release fertilizers industry. The better understanding of the key spray parameters benefits both the environment and low cost coating processes. The use of starch based materials to coat the slow release fertilizers is a new development. However, the hydraulic spray jet breakup of the non-Newtonian starchy solutions is a complex phenomenon and very little known. The aim of this research was to study the axial and radial distributions of the Sauter Mean Diameter (SMD) and velocity vectors in pulsing spray patterns of native and modified tapioca starch solutions. To meet the objective, high speed imaging and Phase Doppler Anemometry (PDA) techniques were employed to characterize the four compositions of the starch-urea-borax complex namely S0, S1, S2 and S3. The unheated solutions exhibited very high viscosities ranging from 2035 to 3030 cP. No jet breakup was seen at any stage of the nozzle operation at an injection pressure of 1-5 bar. However, at 80 °C temperature and 5 bar pressure, the viscosity was reduced to 455 to 638 cP and dense spray patterns emerged from the nozzle obscuring the PDA signals. The axial size distribution revealed a significant decrease in SMD along the spray centreline. The smallest axial SMD (51 to 79 μm) was noticed in S0 spray followed by S1, S2 and S3. Unlikely, the radial SMD in S0 spray did not vary significantly at any stage of the spray injection. This trend was attributed to the continuous growth of the surface wave instabilities on the native starch sheet. However, SMD obtained with S1, S2 and S3 varied appreciably along the radial direction. The mean velocity vector profiles followed the non-Gaussian distribution. The constant vector distributions were seen in the near nozzle regions, where the spray was in the phase of development. In far regions, the velocity vectors were poly-dispersed and a series of ups and downs were seen in the respective radial

  20. Management of primary-to-secondary leaks at Loviisa nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Mohnsen, B.; Jaenkaelae, K. [IVO International Ltd, Vantaa (Finland)

    1995-12-31

    The Loviisa Nuclear power plant consisting of two VVER-440 type press water reactor units has been in commercial operation since the late 1970`s. Specific features for VVER-440 reactors are six primary loops with horizontal steam generators and main gate valves. The structure of the horizontal steam generators construction may cause a large primary to secondary leak in case of a break in the cover of the primary collector. An accident where two primary collector covers opened totally and two covers opened partly took place in Rovno, Ukraine January 1982. Primary to secondary leaks are one of the main contributors to the core melt frequency in VVER reactors according to the Loviisa 1 Probabilistic Safety Assessment. The high core damage contribution has set requirements for the development of effective means to cope with all sizes of primary to secondary leaks in the steam generator. A concept for all leak sizes has been developed for Loviisa 1 and 2. The solution includes four main areas which are a new steam generator leakage monitoring system based on nitrogen-16 measurement, an upgraded pressurizer spray system, an increased emergency cooling water reserve and an automated isolation of the defected steam generator.

  1. Management of primary-to-secondary leaks at Loviisa nuclear power plant

    International Nuclear Information System (INIS)

    Mohnsen, B.; Jaenkaelae, K.

    1995-01-01

    The Loviisa Nuclear power plant consisting of two VVER-440 type press water reactor units has been in commercial operation since the late 1970's. Specific features for VVER-440 reactors are six primary loops with horizontal steam generators and main gate valves. The structure of the horizontal steam generators construction may cause a large primary to secondary leak in case of a break in the cover of the primary collector. An accident where two primary collector covers opened totally and two covers opened partly took place in Rovno, Ukraine January 1982. Primary to secondary leaks are one of the main contributors to the core melt frequency in VVER reactors according to the Loviisa 1 Probabilistic Safety Assessment. The high core damage contribution has set requirements for the development of effective means to cope with all sizes of primary to secondary leaks in the steam generator. A concept for all leak sizes has been developed for Loviisa 1 and 2. The solution includes four main areas which are a new steam generator leakage monitoring system based on nitrogen-16 measurement, an upgraded pressurizer spray system, an increased emergency cooling water reserve and an automated isolation of the defected steam generator

  2. Management of primary-to-secondary leaks at Loviisa nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Mohnsen, B; Jaenkaelae, K [IVO International Ltd, Vantaa (Finland)

    1996-12-31

    The Loviisa Nuclear power plant consisting of two VVER-440 type press water reactor units has been in commercial operation since the late 1970`s. Specific features for VVER-440 reactors are six primary loops with horizontal steam generators and main gate valves. The structure of the horizontal steam generators construction may cause a large primary to secondary leak in case of a break in the cover of the primary collector. An accident where two primary collector covers opened totally and two covers opened partly took place in Rovno, Ukraine January 1982. Primary to secondary leaks are one of the main contributors to the core melt frequency in VVER reactors according to the Loviisa 1 Probabilistic Safety Assessment. The high core damage contribution has set requirements for the development of effective means to cope with all sizes of primary to secondary leaks in the steam generator. A concept for all leak sizes has been developed for Loviisa 1 and 2. The solution includes four main areas which are a new steam generator leakage monitoring system based on nitrogen-16 measurement, an upgraded pressurizer spray system, an increased emergency cooling water reserve and an automated isolation of the defected steam generator.

  3. Swelling behavior of γ-ray irradiated elastomers in boiling spray solution

    International Nuclear Information System (INIS)

    Yagi, Toshiaki; Kusama, Yasuo; Ito, Masayuki; Okada, Sohei; Yoshikawa, Masahito; Yoshida, Kenzo

    1983-05-01

    Elastomers swelled significantly by water sorption during a simulated LOCA test, and this phenomenon could cause the deterioration of their mechanical and electrical properties. Many factors like as radiation, heat, the composition of spray solution, types of elastomers and their formulation, related to the phenomenon. A relationship between swelling properties of the formulation-known various elastomers and the pre-aging conditions such as radiation dose and thermal aging period was studied by measuring their swelling behaviors in boiling spray solution (water and chemical solution). All eight elastomers tested showed remarkable swelling with an increase of radiation dose when they irradiated in air. A swelling in boiling water was about twice of in chemical solution. Some types of Neoprene and Hypalons had an optimum swelling dose where they showed the maxima. Over this dose, the swelling ratio decreased with dose. When irradiated under vacuum, its swelling ratio became significantly lower than that of exposed in air. This attributed the swelling phenomena closely related to radiation oxidation degradation. (author)

  4. Hydrogen generation from aluminium corrosion in reactor containment spray solutions

    International Nuclear Information System (INIS)

    Frid, W.; Karlberg, G.; Sundvall, S.B.

    1982-01-01

    The aluminium corrosion experiments in reactor containment spray solutions, under the conditions expected to prevail during LOCA in BWR and PWR, were performed in order to investigate relationships between temperature, pH and hydrogen production rates. In order to simulate the conditions in a BWR containment realistic ratios between aluminium surface and water volume and between aluminium surface and oxygen volume were used. Three different aluminium alloys were exposed to spray solutions: AA 1050, AA 5052 and AA 6082. The corrosion rates were measured for BWR solutions (deaerated and aerated) with pH 5 and 9 at 50, 100 and 150 0 C. The pressure was constantly 0.8 MPa. The hydrogen production rate was measured by means of gas chromatography. In deionized BWR water the corrosion rates did not exceed about 0.05 mm/year in all cases, i.e. were practically independent of temperature and pH. Hydrogen concentrations were less than 0.1 vol.% in cooled dry gas. Corrosion rates and hydrogen production in PWR alkaline solution measured at pH 9.7 and 150 0 C were very high. AA 5052 alloy was the best material

  5. Aerial spraying to capture released radioactivity from NPP in a severe accident

    Energy Technology Data Exchange (ETDEWEB)

    Younus, Irfan; Yim, Man Sung [KAIST, Daejeon (Korea, Republic of); Medard, Thiphaine [Ecole des Mines de Saint-Etienne, Daejeon (Korea, Republic of)

    2016-05-15

    The proposed strategy in this paper is the use of aqueous spray (water/foam) mixed with suitable chemical additives to capture, dissolve and stabilize the radioactive gases and aerosol particles released from leaked reactor containment and auxiliary building. The spray system can be approached to the leaked reactor building through the use of a truck with high rising cranes, unmanned aerial vehicles (UAVs, such as helicopters), aerostats, or by installing fixed piping structure around the containment building depending on the accident situation. Laboratory-scale experimental system was setup to examine the performance of such systems. The alkaline water (aqueous NaOH.Na{sub 2}S{sub 2}O{sub 3}) and foam-based spray material (sodium lauryl sulphate) were used to examine capture efficiency of gaseous iodine and aerosol particles. The gaseous iodine and aerosol removal efficiency of foam-based spray is higher when compared with alkaline water-based spray. 2. The nozzle producing full cone spray provides the better removal efficiency than nozzle producing hollow cone spray patterns.

  6. Improvement of Physico-mechanical Properties of Partially Amorphous Acetaminophen Developed from Hydroalcoholic Solution Using Spray Drying Technique

    Science.gov (United States)

    Sadeghi, Fatemeh; Torab, Mansour; Khattab, Mostafa; Homayouni, Alireza; Afrasiabi Garekani, Hadi

    2013-01-01

    Objective(s): This study was performed aiming to investigate the effect of particle engineering via spray drying of hydroalcoholic solution on solid states and physico-mechanical properties of acetaminophen. Materials and Methods: Spray drying of hydroalcoholic solution (25% v/v ethanol/water) of acetaminophen (5% w/v) in the presence of small amounts of polyninylpyrrolidone K30 (PVP) (0, 1.25, 2.5 and 5% w/w based on acetaminophen weight) was carried out. The properties of spray dried particles namely morphology, surface characteristics, particle size, crystallinity, dissolution rate and compactibility were evaluated. Results: Spray drying process significantly changed the morphology of acetaminophen crystals from acicular (rod shape) to spherical microparticle. Differential scanning calorimetery (DSC) and x-ray powder diffraction (XRPD) studies ruled out any polymorphism in spray dried samples, however, a major reduction in crystallinity up to 65%, especially for those containing 5% w/w PVP was observed. Spray dried acetaminophen particles especially those obtained in the presence of PVP exhibited an obvious improvement of the dissolution and compaction properties. Tablets produced from spray dried samples exhibited excellent crushing strengths and no tendency to cap. Conclusions: The findings of this study revealed that spray drying of acetaminophen from hydroalcoholic solution in the presence of small amount of PVP produced partially amorphous particles with improved dissolution and excellent compaction properties. PMID:24379968

  7. Hydrogen evolution from aluminium in reactor containment spray solutions

    International Nuclear Information System (INIS)

    Karlberg, G.; Sundvall, S.-B.

    1982-01-01

    Three different aluminium alloys were exposed to conditions similar to BWR and PWR containment spray waters at 50, 100 and 150 0 C. BWR deionized water gives corrosion rates of at most 0.05 mm/year and hydrogen concentrations less than 0.1-1%. On the contrary PWR alkaline solutions give very high corrosion rates and hydrogen contents. (Auth.)

  8. Deposition of Coating to Protect Waste Water Reservoir in Acidic Solution by Arc Thermal Spray Process

    Directory of Open Access Journals (Sweden)

    Han-Seung Lee

    2018-01-01

    Full Text Available The corrosion characteristics of 304 stainless steel (SS and titanium (Ti coatings deposited by the arc thermal spray process in pH 4 solution were assessed. The Ti-sprayed coating exhibits uniform, less porous, and adherent coating morphology compared to the SS-sprayed coating. The electrochemical study, that is, electrochemical impedance spectroscopy (EIS, revealed that as exposure periods to solution were increased, the polarization resistance (Rp decreased and the charge transfer resistance (Rct increased owing to corrosion of the metallic surface and simultaneously at the same time the deposition of oxide films/corrosion on the SS-sprayed surface, while Ti coating transformed unstable oxides into the stable phase. Potentiodynamic studies confirmed that both sprayed coatings exhibited passive tendency attributed due to the deposition of corrosion products on SS samples, whereas the Ti-sprayed sample formed passive oxide films. The Ti coating reduced the corrosion rate by more than six times compared to the SS coating after 312 h of exposure to sulfuric acid- (H2SO4- contaminated water solution, that is, pH 4. Scanning electron microscope (SEM results confirmed the uniform and globular morphology of the passive film on the Ti coating resulting in reduced corrosion. On the other hand, the corrosion products formed on SS-sprayed coating exhibit micropores with a net-like microstructure. X-ray diffraction (XRD revealed the presence of the composite oxide film on Ti-sprayed samples and lepidocrocite (γ-FeOOH on the SS-coated surface. The transformation of TiO and Ti3O into TiO2 (rutile and anatase and Ti3O5 after 312 h of exposure to H2SO4 acid reveals the improved corrosion resistance properties of Ti-sprayed coating.

  9. Superhydrophobic Ceramic Coatings by Solution Precursor Plasma Spray

    Science.gov (United States)

    Cai, Yuxuan

    Superhydrophobic surfaces exhibit superior water repellent properties, and they have remarkable potential to improve current energy infrastructure. Substantial research has been performed on the production of superhydrophobic coatings. However, superhydrophobic coatings have not yet been adopted in many industries where potential applications exist due to the limited durability of the coating materials and the complex and costly fabrication processes. Here presented a novel coating technique to manufacture ceramic superhydrophobic coatings rapidly and economically. A rare earth oxide (REO) was selected as the coating material due to its hydrophobic nature and strong mechanical properties, and deposited on stainless steel substrates by solution precursor plasma spray (SPPS). The as-sprayed coating demonstrated a hierarchically structured coating topography, which closely resembles superhydrophobic surfaces in nature. Compared to smooth REO surfaces, the SPPS superhydrophobic coating improved the water contact angle by as much as 65° after vacuum treatment at 1 Pa for 48 hours.

  10. Effect of precursor solutions on ZnO film via solution precursor plasma spray and corresponding gas sensing performances

    Science.gov (United States)

    Yu, Z. X.; Ma, Y. Z.; Zhao, Y. L.; Huang, J. B.; Wang, W. Z.; Moliere, M.; Liao, H. L.

    2017-08-01

    Solution precursor plasma spraying (SPPS) as a novel thermal spray method was employed to deposit nano-structured ZnO thin film using different formulations of the precursor solution. This article focuses on the influence of the solution composition on the preferential orientation of crystal growth, on crystal size and surface morphology of the resulting ZnO films. The trend of preferential growth along (002) lattice plane of ZnO film was studied by slow scanning X-ray diffraction using a specific coefficient P(002). It appears that the thermal spray process promotes the buildup of ZnO films preferentially oriented along the c-axis. The shape of single particle tends to change from round shaped beads to hexagonal plates by increasing the volume ratio of ethanol in the solvent. Both cauliflower and honeycomb-like surface morphologies featuring high specific surface area and roughness were obtained through the SPPS process by varying solution composition. These ZnO films are hydrophobic with contact angle as high as 136°, which is seemingly associated with micro reliefs developing high surface specific area. Then the gas sensing performances of ZnO films preferentially oriented along (002) face were tentatively predicted using the "first principle calculation method" and were compared with those of conventional films that are mainly oriented along the (101) face. The (002) face displays better hydrogen adsorption capability than the (101) face with much larger resulting changes in electrical resistance. In conclusion, the c-axis oriented ZnO films obtained through SSPS have favorable performances to be used as sensitive layer in gas sensing applications.

  11. Improvement of the Quality and the Shelf Life of the High Oxygen Modified Atmosphere Packaged Veal by Superficial Spraying with Dihydroquercetin Solution

    Directory of Open Access Journals (Sweden)

    Stefan Georgiev Dragoev

    2014-01-01

    Full Text Available The improvement of quality and the shelf life of veal by combination of 80%O2/20%CO2 modified atmosphere packaging and superficial spraying with 0.02% dihydroquercetin solutions was studied. The control samples C, air packaged only, D, air packaged sprayed by 0.02% dihydroquercetin solution, MAP, modified atmosphere packaging only, BMAP, modified atmosphere packaging sprayed by 0.02% butylated hydroxytoluene solution, and DMAP, modified atmosphere packaging sprayed by 0.02% dihydroquercetin solution, were measured. The best results were obtained in modified atmosphere packaging sprayed by 0.02% dihydroquercetin solution. Comparisons with control samples were expressed as reduction in acid value with 27.72%, peroxide value with 64.74%, 2-thiobarbituric acid reactive substances (TBARS with 65.71%, and the pH with 6.18%. The acid and peroxide values, TBARS, and pH were decreased linearly in response when applying the combination of 80%O2/20%CO2 modified atmosphere packaging and superficial spraying with 0.02% dihydroquercetin solutions (P0.05. According to results obtained it was concluded that 80%O2/20%CO2 modified atmosphere packaged veal stored at 0±0.5°C after 0.02% dihydroquercetin solution treatment can preserve its quality and shelf life to 15 d postmortem.

  12. A study on the decontamination of insoles colonized by Trichophyton rubrum: effect of terbinafine spray powder 1% and terbinafine spray solution 1%.

    Science.gov (United States)

    Feuilhade de Chauvin, M

    2012-07-01

    Shoes worn with bare feet function as a fungal reservoir and lead to persistent dermatophytosis. This study was designed to evaluate two formulations of terbinafine (1% spray powder or solution) to treat the insoles of shoes colonized by skin scales infected with Trichophyton rubrum and to determine the contact time necessary to achieve decontamination. Infected skin scales weighing 0.5 g, taken from the feet of patients with confirmed T. rubrum infection, was dispersed onto insoles pre-moistened with sterile saline solution (to mimic perspiration). Three types of insole were tested (felt, latex, leather). After inoculation, insoles were placed separately in new cardboard boxes at ambient temperature, and re-humidified with sterile normal saline solution for 48 h before being treated; untreated insoles served as controls. Scales were scraped off at 48 h or 96 h, and dropped into tubes of Sabouraud agar, incubated at 27°C and examined at 3 and 6 weeks. Cultures from all control insoles showed numerous T. rubrum colonies. In contrast, cultures from all insoles treated with a single application of terbinafine 1% spray solution or powder, and taken after 48 h or 96 h contact with the product, remained sterile at 3 weeks and 6 weeks. This study demonstrated the successful treatment of insoles colonized by T. rubrum-infected skin scales. Terbinafine 1% spray solution and powder showed good efficacy; the dermatophyte could no longer be cultured 48 h after a single application of terbinafine. © 2011 The Author. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

  13. Calibration of a leak detection spectrometer

    International Nuclear Information System (INIS)

    Geller, R.

    1958-01-01

    This paper describes a study of the possible methods for calibrating a leak detection spectrometer, and the estimation of outputs from the leaks is considered. With this in mind the question of sensitivity of leak detection is tackled on a very general level; first the sensitivity of the isolated instrument is determined, and then the sensitivity of an instrument connected to an installation where leaks may be suspected. Finally, practical solutions are proposed. (author) [fr

  14. Tungsten oxide coatings deposited by plasma spray using powder and solution precursor for detection of nitrogen dioxide gas

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chao, E-mail: zhangc@yzu.edu.cn [College of Mechanical Engineering, Yangzhou University, Yangzhou 225127 (China); Wang, Jie [College of Mechanical Engineering, Yangzhou University, Yangzhou 225127 (China); Geng, Xin [College of Mechanical Engineering, Yangzhou University, Yangzhou 225127 (China); College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002 (China)

    2016-05-25

    Increasing attention has been paid on preparation methods for resistive-type gas sensors based on semiconductor metal oxides. In this work, tungsten oxide (WO{sub 3}) coatings were prepared on alumina substrates and used as gas sensitive layers. The coatings were deposited by atmospheric plasma spray using powder, solution precursor, or a combination of both. Tungsten oxide powder through a powder port and ammonium tungstate aqueous solution through a liquid port were injected into plasma stream respectively or together to deposit WO{sub 3} coatings. Phase structures in the coatings were characterized by X-ray diffraction analyzer. The field-emission scanning electron microscopy images confirmed that the coatings were in microstructure, nanostructure or micro-nanostructure. The sensing properties of the sensors based on the coatings exposed to 1 ppm nitrogen dioxide gas were characterized in a home-made instrument. Sensing properties of the coatings were compared and discussed. The influences of gas humidity and working temperature on the sensor responses were further studied. - Highlights: • Porous gas sensitive coatings were deposited by plasma spray using powder and solution precursor. • Crystallized WO{sub 3} were obtained through hybrid plasma spray plus a pre-conditioned step. • Plasma power had an important influence on coating microstructure. • The particle size of atmospheric plasma-sprayed microstructured coating was stable. • Solution precursor plasma-sprayed WO{sub 3} coatings had nanostructure and showed good responses to 1 ppm NO{sub 2}.

  15. Leak detection on the DIII-D tokamak using helium entrainment techniques

    International Nuclear Information System (INIS)

    Brooks, N.H.; Baxi, C.; Anderson, P.

    1988-01-01

    The entrainment of helium in a viscous gas flow was utilized to compartmentalize, and then to pinpoint, a leak across the inner skin of the double-walled DIII-D vacuum vessel. Inaccessible from the outside, the leak connected the cooling channels in the wall interspace with the primary vacuum chamber. By entraining helium in the pressurized flow from the single-pass gas circulation system, well-defined portions of the wall were exposed to helium without disassembly of the poorly accessible cooling manifolds. Varying the helium injection point permitted the localization of the leak to a single 30 0 toroidal sector of the vessel. The exact location of the leak was found from inside the vessel by spraying helium on suspect regions, while sweeping the contents of the cooling channels to the foreline of a Varian Contraflow leak detector with a 0.1 Pa m 3 /s flow of nitrogen. Flow speed calculations were used to predict the response time to entrained helium of the actual leak detection setup

  16. On a strong solution of the non-stationary Navier-Stokes equations under slip or leak boundary conditions of friction type

    Science.gov (United States)

    Kashiwabara, Takahito

    Strong solutions of the non-stationary Navier-Stokes equations under non-linearized slip or leak boundary conditions are investigated. We show that the problems are formulated by a variational inequality of parabolic type, to which uniqueness is established. Using Galerkin's method and deriving a priori estimates, we prove global and local existence for 2D and 3D slip problems respectively. For leak problems, under no-leak assumption at t=0 we prove local existence in 2D and 3D cases. Compatibility conditions for initial states play a significant role in the estimates.

  17. Effect of precursor solutions on ZnO film via solution precursor plasma spray and corresponding gas sensing performances

    International Nuclear Information System (INIS)

    Yu, Z.X.; Ma, Y.Z.; Zhao, Y.L.; Huang, J.B.; Wang, W.Z.; Moliere, M.; Liao, H.L.

    2017-01-01

    Highlights: • C-axis preferential oriented grown ZnO films were firstly deposited via SPPS with different solutions. • ZnO films were hydrophobic due to cauliflower and honeycomb-like surface morphologies with high surface specific area. • Gas detecting performance of (002) plane oriented ZnO was predicted and compared by “first principle calculation method”. - Abstract: Solution precursor plasma spraying (SPPS) as a novel thermal spray method was employed to deposit nano-structured ZnO thin film using different formulations of the precursor solution. This article focuses on the influence of the solution composition on the preferential orientation of crystal growth, on crystal size and surface morphology of the resulting ZnO films. The trend of preferential growth along (002) lattice plane of ZnO film was studied by slow scanning X-ray diffraction using a specific coefficient P_(_0_0_2_)_. It appears that the thermal spray process promotes the buildup of ZnO films preferentially oriented along the c-axis. The shape of single particle tends to change from round shaped beads to hexagonal plates by increasing the volume ratio of ethanol in the solvent. Both cauliflower and honeycomb-like surface morphologies featuring high specific surface area and roughness were obtained through the SPPS process by varying solution composition. These ZnO films are hydrophobic with contact angle as high as 136°, which is seemingly associated with micro reliefs developing high surface specific area. Then the gas sensing performances of ZnO films preferentially oriented along (002) face were tentatively predicted using the “first principle calculation method” and were compared with those of conventional films that are mainly oriented along the (101) face. The (002) face displays better hydrogen adsorption capability than the (101) face with much larger resulting changes in electrical resistance. In conclusion, the c-axis oriented ZnO films obtained through SSPS have

  18. Effect of precursor solutions on ZnO film via solution precursor plasma spray and corresponding gas sensing performances

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Z.X., E-mail: zexin.yu@utbm.fr [Univ Bourgogne Franche Comte, CNRS, Lab ICB, UMR 6303, Site UTBM, F-90010 Belfort (France); Ma, Y.Z., E-mail: yangzhou.ma@outlook.com [School of Materials Science and Engineering, Anhui University of Technology, Ma’anshan 243002 (China); Zhao, Y.L. [Univ Bourgogne Franche Comte, CNRS, Lab ICB, UMR 6303, Site UTBM, F-90010 Belfort (France); Huang, J.B.; Wang, W.Z. [Key Lab of Safety Science of Pressurized System, Ministry of Education, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237 (China); Moliere, M.; Liao, H.L. [Univ Bourgogne Franche Comte, CNRS, Lab ICB, UMR 6303, Site UTBM, F-90010 Belfort (France)

    2017-08-01

    Highlights: • C-axis preferential oriented grown ZnO films were firstly deposited via SPPS with different solutions. • ZnO films were hydrophobic due to cauliflower and honeycomb-like surface morphologies with high surface specific area. • Gas detecting performance of (002) plane oriented ZnO was predicted and compared by “first principle calculation method”. - Abstract: Solution precursor plasma spraying (SPPS) as a novel thermal spray method was employed to deposit nano-structured ZnO thin film using different formulations of the precursor solution. This article focuses on the influence of the solution composition on the preferential orientation of crystal growth, on crystal size and surface morphology of the resulting ZnO films. The trend of preferential growth along (002) lattice plane of ZnO film was studied by slow scanning X-ray diffraction using a specific coefficient P{sub (002).} It appears that the thermal spray process promotes the buildup of ZnO films preferentially oriented along the c-axis. The shape of single particle tends to change from round shaped beads to hexagonal plates by increasing the volume ratio of ethanol in the solvent. Both cauliflower and honeycomb-like surface morphologies featuring high specific surface area and roughness were obtained through the SPPS process by varying solution composition. These ZnO films are hydrophobic with contact angle as high as 136°, which is seemingly associated with micro reliefs developing high surface specific area. Then the gas sensing performances of ZnO films preferentially oriented along (002) face were tentatively predicted using the “first principle calculation method” and were compared with those of conventional films that are mainly oriented along the (101) face. The (002) face displays better hydrogen adsorption capability than the (101) face with much larger resulting changes in electrical resistance. In conclusion, the c-axis oriented ZnO films obtained through SSPS have

  19. High level helium leak testing methods developed at ICSI Rm. Valcea

    International Nuclear Information System (INIS)

    Saros, Gili; Armeanu, Adrian; Saros, Irina; Ciortea, Constantin

    2007-01-01

    Full text: Helium leak detection is one of the most widely used methods of nondestructive testing in use today. In principle two methods are applied for leak testing and localization of leaks, the 'Vacuum method' and the 'Overpressure method'. In case of the 'Vacuum method' the object to be examined for leaks is evacuated and filled instead with Helium. The gas penetrates through any leaks found in the object and is detected by the leak test instrument. In case of the 'Overpressure method' the object to be examined for leaks is filled with Helium, under slight overpressure. The gas escapes through any leaks present and it is detected by a detector probe. This detector probe sometimes called a 'sniffer' acting as a gas sampling probe. Varian 979 Helium Leak Detector has a built-in turbo pump and an externally mounted dry forepump located below the system. The leak detector is configured for the evacuation type leak testing. In this case, the vacuum system under test is evacuated by the leak detector. Helium is then sprayed on the outside of the vacuum system and is pumped into the leak detector if a leak is present. The leak detector is capable to detect leaks down to 10 -9 atm-cc/sec range. The Specton 300E is a strong, rugged leak detector designed to operate in dirty industrial conditions as well as clean research areas. A number of applications are mentioned: - Generators; - Buried Pipelines; - Chemical and power plants; - Vacuum furnace installations; - Heat Exchangers; - Tank Floors; - Nuclear research centers; - Refrigeration installations; - Any type of industrial vacuum system. (authors)

  20. Characterization of Modified Tapioca Starch Solutions and Their Sprays for High Temperature Coating Applications

    Science.gov (United States)

    Naz, M. Y.; Sulaiman, S. A.; Ariwahjoedi, B.; Shaari, Ku Zilati Ku

    2014-01-01

    The objective of the research was to understand and improve the unusual physical and atomization properties of the complexes/adhesives derived from the tapioca starch by addition of borate and urea. The characterization of physical properties of the synthesized adhesives was carried out by determining the effect of temperature, shear rate, and mass concentration of thickener/stabilizer on the complex viscosity, density, and surface tension. In later stage, phenomenological analyses of spray jet breakup of heated complexes were performed in still air. Using a high speed digital camera, the jet breakup dynamics were visualized as a function of the system input parameters. The further analysis of the grabbed images confirmed the strong influence of the input processing parameters on full cone spray patternation. It was also predicted that the heated starch adhesive solutions generate a dispersed spray pattern by utilizing the partial evaporation of the spraying medium. Below 40°C of heating temperature, the radial spray cone width and angle did not vary significantly with increasing Reynolds and Weber numbers at early injection phases leading to increased macroscopic spray propagation. The discharge coefficient, mean flow rate, and mean flow velocity were significantly influenced by the load pressure but less affected by the temperature. PMID:24592165

  1. Spray-dried HPMC microparticles of Indomethacin: Impact of drug-polymer ratio and viscosity of the polymeric solution on dissolution

    International Nuclear Information System (INIS)

    Alanazi, Fars K.; El-Badry, M.; Alsarra, Ibrahim A.

    2006-01-01

    Polymeric microparticles prepared by spray-drying techniques were investigated to enhance the dissolution rate of indomethacin (IM) in comparison with conventional microparticles prepared by co-precipitation solid dispersion method. Drug-polymer ratios and viscosity of polymeric solutions as potential factors were used in order to enhance the dissolution rate of IM. Spray-drying technique was used for preparing of microparticles using aqueous suspension of IM in hydroxypropyl methylcellulose (HPMC) polymer solution. The effect of drug-polymer ratios on dissolution rates of IM was studied in simulating intestinal medium. IM was analyzed spectrophotometrically at λ =320nm. For each drug-polymer ratios, low and high viscosity polymeric solutions were prepared and their impacts on the dissolution of IM were observed. Microparticles were morphologically characterized by optical microscopy. The interaction between IM and HPMC was studied by differential scanning caloremetry (DSC) and x-ray diffractometry (XRD). Spherical fluffy microparticles of IM were obtained using HPMC. It was observed that the prepared spray-dried microparticles significantly increase the dissolution rate of IM. The increase in dissolution rates was achieved with drug: polymer ratios 1: 1 as well as 1:2 and interestingly, the decrease in drug content in ratio exceeding 1:2 resulted in reduction in dissolution rates. Also, with all drug-polymer ratios, the low viscosity polymeric solutions gave the higher dissolution rates. In conclusion, HPMC microparticles loaded with IM were prepared by spray drying-technique and the potential of this technique to enhance the dissolution was studied. The findings indicate that the dissolution profile of IM microparticles prepared by spray -drying technique relied on drug-polymer ratios and viscosity of polymeric solutions. (author)

  2. Influence of pH of spray solution on optoelectronic properties of cadmium oxide thin films

    International Nuclear Information System (INIS)

    Hodlur, R. M.; Rabinal, M. K.

    2015-01-01

    Highly conducting transparent cadmium oxide thin films were prepared by the conventional spray pyrolysis technique. The pH of the spray solution is varied by adding ammonia/hydrochloric acid. The effect of pH on the morphology, crystallinity and optoelectronic properties of these films is studied. The structural analysis showed all the films in the cubic phase. For the films with pH < 7 (acidic condition), the preferred orientation is along the (111) direction and for those with pH >7 (alkaline condition), the preferred orientation is along the (200) direction. A lowest resistivity of 9.9 × 10 −4 Ω·cm (with carrier concentration = 5.1 × 10 20 cm −3 , mobility = 12.4 cm 2 /(V·s)) is observed for pH ≈ 12. The resistivity is tuned almost by three orders of magnitude by controlling the bath pH with optical transmittance more than 70%. Thus, the electrical conductivity of CdO films could be easily tuned by simply varying the pH of the spray solution without compromising the optical transparency. (paper)

  3. Deposition of nanostructured photocatalytic zinc ferrite films using solution precursor plasma spraying

    International Nuclear Information System (INIS)

    Dom, Rekha; Sivakumar, G.; Hebalkar, Neha Y.; Joshi, Shrikant V.; Borse, Pramod H.

    2012-01-01

    Highlights: ► Highly economic solution precursor route capable of producing films/coating even for mass scale production. ► Pure spinel phase ZnFe 2 O 4 porous, immobilized films deposited in single step. ► Parameter optimization yields access to nanostructuring in SPPS method. ► The ecofriendly immobilized ferrite films were active under solar radiation. ► Such magnetic system display advantage w.r.t. recyclability after photocatalyst extraction. -- Abstract: Deposition of pure spinel phase, photocatalytic zinc ferrite films on SS-304 substrates by solution precursor plasma spraying (SPPS) has been demonstrated for the first time. Deposition parameters such as precursor solution pH, concentration, film thickness, plasma power and gun-substrate distance were found to control physico-chemical properties of the film, with respect to their crystallinity, phase purity, and morphology. Alkaline precursor conditions (7 2 O 4 film. Very high/low precursor concentrations yielded mixed phase, less adherent, and highly inhomogeneous thin films. Desired spinel phase was achieved in as-deposited condition under appropriately controlled spray conditions and exhibited a band gap of ∼1.9 eV. The highly porous nature of the films favored its photocatalytic performance as indicated by methylene blue de-coloration under solar radiation. These immobilized films display good potential for visible light photocatalytic applications.

  4. Novel Methods of Hydrogen Leak Detection

    International Nuclear Information System (INIS)

    Pushpinder S Puri

    2006-01-01

    For hydrogen to become a consumer fuel for automotive and domestic power generation, safety is paramount. Today's hydrogen systems are built with inherent safety measures and multiple levels of protection. However, human senses, in particular, the sense of smell, is considered the ultimate safeguards against leaks. Since hydrogen is an odorless gas, use of odorants to detect leaks, as is done in case of natural gas, is obvious solution. The odorants required for hydrogen used in fuel cells have a unique requirement which must be met. This is because almost all of the commercial odorants used in gas leak detection contain sulfur which acts as poison for the catalysts used in hydrogen based fuel cells, most specifically for the PEM (polymer electrolyte membrane or proton exchange membrane) fuel cells. A possible solution to this problem is to use non-sulfur containing odorants. Chemical compounds based on mixtures of acrylic acid and nitrogen compounds have been adopted to achieve a sulfur-free odorization of a gas. It is, therefore, desired to have a method and system for hydrogen leak detection using odorant which can incorporate a uniform concentration of odorant in the hydrogen gas, when odorants are mixed in the hydrogen storage or delivery means. It is also desired to develop methods where the odorant is not added to the bulk hydrogen, keeping it free of the odorization additives. A series of novel solutions are proposed which address the issues raised above. These solutions are divided into three categories as follows: 1. Methods incorporating an odorant in the path of hydrogen leak as opposed to adding it to the hydrogen gas. 2. Methods where odorants are generated in-situ by chemical reaction with the leaking hydrogen 3. Methods of dispensing and storing odorants in high pressure hydrogen gas which release odorants to the gas at a uniform and predetermined rates. Use of one or more of the methods described here in conjunction with appropriate engineering

  5. Efficacy, tolerability and consumer acceptability of terbinafine topical spray versus terbinafine topical solution: a phase IIa, randomised, observer-blind, comparative study.

    Science.gov (United States)

    Brown, Marc; Evans, Charles; Muddle, Andrew; Turner, Rob; Lim, Sian; Reed, Jessica; Traynor, Matt

    2013-10-01

    Tinea pedis is one of the world's most prevalent dermatophyte infections. MedSpray™ tinea pedis 1 % w/w (topical spray) is a novel, easy-to-use propellant-based spray formulation containing 1 % w/w terbinafine, requiring no manipulation at the site of infection. This is in contrast to the only formulation currently approved in Europe for single application (none are approved in the USA for single use), which is Lamisil(®) Once 1 % w/w (topical solution), containing 1 % w/w terbinafine hydrochloride, which requires manipulation on the affected area. The aim of this study was to evaluate the efficacy, tolerability and consumer acceptability of a topical spray versus a topical solution in the treatment of tinea pedis. This study is a phase IIa, randomised, observer-blind, non-inferiority comparative study of the topical spray compared with the topical solution over a 12-week study period. The study was conducted at Bioskin GmbH, Hamburg and Berlin. Patients (n = 120) who presented with the presence of interdigital tinea pedis caused by dermatophytes on one or both feet were enrolled in the study. Patients were randomly assigned between the two treatment groups. Either the topical spray or the topical solution was administered by the study nurse and consisted of a single application (equivalent to 20 mg of terbinafine per foot) on day 1 of the study. No further applications were made for the duration of the study. The hypothesis formulated before commencement of the study was that the topical spray would prove to be non-inferior to the topical solution. Efficacy assessments, including clinical signs and symptoms, mycology and microscopy were performed at baseline and 1, 6 and 12 weeks after treatment. The rate of mycological cure at week 1 was statistically equivalent for both treatments. There was a significant reduction in the overall clinical score as assessed by the Physician's Global Assessment of signs and symptoms for both treatment groups. The topical

  6. Mobile Sensor Networks for Leak and Backflow Detection in Water Distribution Systems

    KAUST Repository

    Suresh, M. Agumbe; Smith, L.; Rasekh, A.; Stoleru, R.; Banks, M.K.; Shihada, Basem

    2014-01-01

    Leak and backflow detection are essential aspects of Water Distribution System (WDS) monitoring. Most existing solutions for leak/backflow detection in WDSs focus on the placement of expensive static sensors located strategically. In contrast to these, we propose a solution whereby mobile sensors (i.e., their movement aided only by the inherent water flow in the system) detect leaks/backflow. Information about the leaks/backflow is collected from the sensors either by physically capturing them, or through wireless communication. Specifically, we propose models to maximize leak/backflow detection given a cost constraint (a limit on the number of sensors). Through extensive simulations, we demonstrate the superior performance of our proposed solution when compared with the state of the art solutions (e.g., algorithms/protocols and analysis).

  7. Mobile Sensor Networks for Leak and Backflow Detection in Water Distribution Systems

    KAUST Repository

    Suresh, M. Agumbe

    2014-05-01

    Leak and backflow detection are essential aspects of Water Distribution System (WDS) monitoring. Most existing solutions for leak/backflow detection in WDSs focus on the placement of expensive static sensors located strategically. In contrast to these, we propose a solution whereby mobile sensors (i.e., their movement aided only by the inherent water flow in the system) detect leaks/backflow. Information about the leaks/backflow is collected from the sensors either by physically capturing them, or through wireless communication. Specifically, we propose models to maximize leak/backflow detection given a cost constraint (a limit on the number of sensors). Through extensive simulations, we demonstrate the superior performance of our proposed solution when compared with the state of the art solutions (e.g., algorithms/protocols and analysis).

  8. [Leak on underground pipings. Corrosion in containment spray systems at Bugey NPP (Preliminary Information)

    International Nuclear Information System (INIS)

    1996-01-01

    During last refuelling shutdown at BUGEY 3, this year on the fourteenth of February, the plant operator discovered a wide corrosion on the reactor vessel head and its equipments. The reactor head vessel had recently been replaced by a new one since last reactor shutdown in order to treat the vessel head adaptor safety problem. The cause of this corrosion is a small primary leak on this pipe flange. The leak had been found fortuitously during a field inspection of valves while there was not reactor charge, seven months before the reactor was shutdown for refuelling. At this time the primary leak had been leaktighted by closure of a manual valve and the reactor was restarted up

  9. Spray-on polyvinyl alcohol separators and impact on power production in air-cathode microbial fuel cells with different solution conductivities

    KAUST Repository

    Hoskins, Daniel L.

    2014-11-01

    © 2014 Elsevier Ltd. Separators are used to protect cathodes from biofouling and to avoid electrode short-circuiting, but they can adversely affect microbial fuel cell (MFC) performance. A spray method was used to apply a polyvinyl alcohol (PVA) separator to the cathode. Power densities were unaffected by the PVA separator (339 ± 29 mW/m2), compared to a control lacking a separator in a low conductivity solution (1mS/cm) similar to wastewater. Power was reduced with separators in solutions typical of laboratory tests (7-13 mS/cm), compared to separatorless controls. The PVA separator produced more power in a separator assembly (SEA) configuration (444 ± 8 mW/m2) in the 1mS/cm solution, but power was reduced if a PVA or wipe separator was used in higher conductivity solutions with either Pt or activated carbon catalysts. Spray and cast PVA separators performed similarly, but the spray method is preferred as it was easier to apply and use.

  10. Application of a novel 3-fluid nozzle spray drying process for the microencapsulation of therapeutic agents using incompatible drug-polymer solutions.

    Science.gov (United States)

    Sunderland, Tara; Kelly, John G; Ramtoola, Zebunnissa

    2015-04-01

    The aim of this study was to evaluate a novel 3-fluid concentric nozzle (3-N) spray drying process for the microencapsulation of omeprazole sodium (OME) using Eudragit L100 (EL100). Feed solutions containing OME and/or EL100 in ethanol were assessed visually for OME stability. Addition of OME solution to EL100 solution resulted in precipitation of OME followed by degradation of OME reflected by a colour change from colourless to purple and brown. This was related to the low pH of 2.8 of the EL100 solution at which OME is unstable. Precipitation and progressive discoloration of the 2-fluid nozzle (2-N) feed solution was observed over the spray drying time course. In contrast, 3-N solutions of EL100 or OME in ethanol were stable over the spray drying period. Microparticles prepared using either nozzle showed similar characteristics and outer morphology however the internal morphology was different. DSC showed a homogenous matrix of drug and polymer for 2-N microparticles while 3-N microparticles had defined drug and polymer regions distributed as core and coat. The results of this study demonstrate that the novel 3-N spray drying process can allow the microencapsulation of a drug using an incompatible polymer and maintain the drug and polymer in separate regions of the microparticles.

  11. Investigation of factors affecting the stability of lysozyme spray dried from ethanol-water solutions

    DEFF Research Database (Denmark)

    Ji, Shuying; Thulstrup, Peter Waaben; Mu, Huiling

    2017-01-01

    -ethanol mixtures. The effect of formulation additives (trehalose, Tween 20 and phosphate-buffered saline) and processing conditions (inlet temperature and storage time of lysozyme in the feed solution before the spray drying process) on the protein bioactivity was investigated. The results showed...

  12. Small-Scale Spray Releases: Additional Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, G. N.; Mahoney, Lenna A.; Tran, Diana N.; Burns, Carolyn A.; Kurath, Dean E.

    2013-08-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are largely absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale. The small-scale testing and resultant data are described in Mahoney et al. (2012b) and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the

  13. Large-Scale Spray Releases: Additional Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Richard C.; Gauglitz, Phillip A.; Burns, Carolyn A.; Fountain, Matthew S.; Shimskey, Rick W.; Billing, Justin M.; Bontha, Jagannadha R.; Kurath, Dean E.; Jenks, Jeromy WJ; MacFarlan, Paul J.; Mahoney, Lenna A.

    2013-08-01

    One of the events postulated in the hazard analysis for the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak event involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids that behave as a Newtonian fluid. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and in processing facilities across the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are mostly absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale testing. The small-scale testing and resultant data are described in Mahoney et al. (2012b), and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used

  14. Depressurization as a means of leak checking large vacuum vessels

    International Nuclear Information System (INIS)

    Callis, R.W.; Langhorn, A.; Petersen, P.I.; Ward, C.; Wesley, J.

    1985-01-01

    A common problem associated with large vacuum vessels used in magnetic confinement fusion experiments is that leak checking is hampered by the inaccessibility to most of the vacuum vessel surface. This inaccessibility is caused by the close proximity of magnetic coils, diagnostics and, for those vessels that are baked, the need to completely surround the vessel with a thermal insulation blanket. These obstructions reduce the effectiveness of the standard leak checking method of using a mass spectrometer and spraying a search gas such as helium on the vessel exterior. Even when the presence of helium is detected, its entry point into the vessel cannot always be pinpointed. This paper will describe a method of overcoming this problem. By slightly depressurizing the vessel, an influx of helium through the leak is created. The leak site can then be identified by personnel within the vessel using standard sniffing procedures. There are two conditions which make this method of leak checking practical. First, the vessel need only be depressurized 2 psi, thus allowing personnel inside to perform the sniffing operation. Second, the sniffing probe used (Leybold--Heraus ''Quick Test'') could detect a change in helium concentration as small as 100 ppb, which allows for faster scanning of the vessel inferior. Use of this technique to find an elusive 10 -3 Torrxl/s leak in the Doublet III tokamak vacuum vessel will be presented

  15. Novel Methods of Hydrogen Leak Detection

    International Nuclear Information System (INIS)

    Pushpinder S Puri

    2006-01-01

    With the advent of the fuel cell technology and a drive for clean fuel, hydrogen gas is emerging as a leading candidate for the fuel of choice. For hydrogen to become a consumer fuel for automotive and domestic power generation, safety is paramount. It is, therefore, desired to have a method and system for hydrogen leak detection using odorant which can incorporate a uniform concentration of odorant in the hydrogen gas, when odorants are mixed in the hydrogen storage or delivery means. It is also desired to develop methods where the odorant is not added to the bulk hydrogen, keeping it free of the odorization additives. When odorants are not added to the hydrogen gas in the storage or delivery means, methods must be developed to incorporate odorant in the leaking gas so that leaks can be detected by small. Further, when odorants are not added to the stored hydrogen, it may also be desirable to observe leaks by sight by discoloration of the surface of the storage or transportation vessels. A series of novel solutions are proposed which address the issues raised above. These solutions are divided into three categories as follows: 1. Methods incorporating an odorant in the path of hydrogen leak as opposed to adding it to the hydrogen gas. 2. Methods where odorants are generated in-situ by chemical reaction with the leaking hydrogen 3. Methods of dispensing and storing odorants in high pressure hydrogen gas which release odorants to the gas at a uniform and predetermined rates. Use of one or more of the methods described here in conjunction with appropriate engineering solutions will assure the ultimate safety of hydrogen use as a commercial fuel. (authors)

  16. Analytical study of sodium combustion phenomena under sodium leak accidents

    International Nuclear Information System (INIS)

    Kim, Byung Ho; Jeong, J. Y.; Jeong, K. C.; Kim, T. J.; Choi, J. H.

    2001-12-01

    The rise of temperature and pressure, the release of aerosol in the buildings as a result of sodium fire must be considered for the safety measures of LMR. Therefore for the safety of the LMR, it is necessary to understand the characteristics of sodium fire, resulting from the various type of leakage. ASSCOPS(Analysis of Simultaneous Sodium Combustion in Pool and Spray) is the computer code for the analysis of the thermal consequence of sodium leak and fire in LMR that has been developed by Japan Nuclear Cycle Development Institute(JNC) in Japan. In this study, a preliminary analysis of sodium leak and fire accidents in S/G building of KALIMER is made by using ASSCOPS code. Various phenomena of interest are spray and pool burning, peak pressure, temperature change, local structure temperature, aerosol behavior, drain system into smothering tank, ventilation characteristics at each cell with the safety venting system and nitrogen injection system. In this calculation, the dimension of the S/G building was chosen in accordance with the selected options of LMR name KALIMER(Korea). As a result of this study, it was shown that subsequent effect of sodium fire depended upon whether the sodium continued to leak from the pipe or not, whether the ventilation system was running, whether the inert gas injection system was provided, whether the sodium on floor was drained into the smothering tank or not, whether the building was sealed or not, etc. Specially the excessive rise of pressure into each cell was prevented by installing the pressure release plates on wall of the building

  17. Engineering a new class of thermal spray nano-based microstructures from agglomerated nanostructured particles, suspensions and solutions: an invited review

    Science.gov (United States)

    Fauchais, P.; Montavon, G.; Lima, R. S.; Marple, B. R.

    2011-03-01

    From the pioneering works of McPherson in 1973 who identified nanometre-sized features in thermal spray conventional alumina coatings (using sprayed particles in the tens of micrometres size range) to the most recent and most advanced work aimed at manufacturing nanostructured coatings from nanometre-sized feedstock particles, the thermal spray community has been involved with nanometre-sized features and feedstock for more than 30 years. Both the development of feedstock (especially through cryo-milling, and processes able to manufacture coatings structured at the sub-micrometre or nanometre sizes, such as micrometre-sized agglomerates made of nanometre-sized particles for feedstock) and the emergence of thermal spray processes such as suspension and liquid precursor thermal spray techniques have been driven by the need to manufacture coatings with enhanced properties. These techniques result in two different types of coatings: on the one hand, those with a so-called bimodal structure having nanometre-sized zones embedded within micrometre ones, for which the spray process is similar to that of conventional coatings and on the other hand, sub-micrometre or nanostructured coatings achieved by suspension or solution spraying. Compared with suspension spraying, solution precursor spraying uses molecularly mixed precursors as liquids, avoiding a separate processing route for the preparation of powders and enabling the synthesis of a wide range of oxide powders and coatings. Such coatings are intended for use in various applications ranging from improved thermal barrier layers and wear-resistant surfaces to thin solid electrolytes for solid oxide fuel cell systems, among other numerous applications. Meanwhile these processes are more complex to operate since they are more sensitive to parameter variations compared with conventional thermal spray processes. Progress in this area has resulted from the unique combination of modelling activities, the evolution of

  18. Acoustic emission leak monitoring system LMS-96

    International Nuclear Information System (INIS)

    Liska, J.; Cvrcek, M.; Mueller, L.

    1997-01-01

    On-line acoustic emission leak monitoring under industrial conditions of nuclear power plants is a problem with specific features setting specific demands on the leak monitoring system. The paper briefly reviews those problems (attenuation pattern of a real structure, acoustic background, alarm system, etc.) and the solution of some of them is discussed. Information is presented on the Acoustic Emission Leak Monitoring System LMS-96 by SKODA NUCLEAR MACHINERY and the system's function is briefly described. (author)

  19. Effect of Solution Molarity, Substrate Temperature and Spray Time on The Structural and Optical Properties Of ZnO Thin Films Deposited By Spray Pyrolysis

    International Nuclear Information System (INIS)

    Ramadan, A.A.; Hashem, H. M.; El-Sayed, S. M.; Ashour, A.H.; Abdel-Haleem, S.M.

    2013-01-01

    Zinc oxide thin films were deposited on a glass substrate by spray pyrolysis technique using solution of zinc acetate and air as the carrier gas. Effects of solution molarity, substrate temperature and spray time on films properties were investigated. All films deposited were characterized using X-ray diffraction for structural characterization and UV-VIS transmission spectrophotometry for optical properties. According to the analytical method, the type of crystal lattice was found to be hexagonal and X-ray diffraction (XRD) patterns showed that the films deposited were polycrystalline with (002) plane as preferential orientation. The values of lattice constant, grain size, micro strain and dislocation density of all samples were calculated. In addition, Optical behaviors of film samples were analyzed by obtaining transmission spectra, in the wavelength range of 350-800 nm. The UV-VIS spectroscopy shows the high transparency of ZnO films in the UV region. An optimization of the films has been carried out to determine the best preparation conditions.

  20. Series Solution for Steady Three-Dimensional Flow due to Spraying on Inclined Spinning Disk by Homotopy Perturbation Method

    Directory of Open Access Journals (Sweden)

    Saeed Dinarvand

    2012-01-01

    Full Text Available The steady three-dimensional flow of condensation or spraying on inclined spinning disk is studied analytically. The governing nonlinear equations and their associated boundary conditions are transformed into the system of nonlinear ordinary differential equations. The series solution of the problem is obtained by utilizing the homotopy perturbation method (HPM. The velocity and temperature profiles are shown and the influence of Prandtl number on the heat transfer and Nusselt number is discussed in detail. The validity of our solutions is verified by the numerical results. Unlike free surface flows on an incline, this through flow is highly affected by the spray rate and the rotation of the disk.

  1. Effect of NaCl Solution Spraying on Fatigue Lives of Smooth and Slit Specimens of 0.37% Carbon Steel

    Science.gov (United States)

    Makabe, Chobin; Ferdous, Md. Shafiul; Shimabukuro, Akimichi; Murdani, Anggit

    2017-07-01

    The fatigue crack initiation life and growth rate are affected by experimental conditions. A corrosive environment can be created in a laboratory by means of dropping salt water onto the specimen surface, spraying chloride mist into the experimental chamber, etc. In the case of smooth specimens of some metals, fatigue life is shortened and the fatigue limit disappears under such corrosive experimental conditions. In this study, the effects of intermittent spraying of 3% NaCl solution-mist on corrosion fatigue behavior were investigated. The material used was 0.37% carbon steel. This is called JIS S35C in Japan. Spraying of 3% NaCl solution-mist attacked the surface layer of the specimen. It is well known that the pitting, oxidation-reduction reaction, etc. affect the fatigue strength of metals in a corrosive environment. We carried out corrosion fatigue tests with smooth specimens, holed specimens and slit specimens. Then the effects of such specimen geometry on the fatigue strength were investigated when the NaCl solution-mist was sprayed onto the specimen surface. In the case of lower stress amplitude application in slit specimens, the fatigue life in a corrosive atmosphere was longer than that in the open air. It is discussed that the behavior is related to the crack closure which happens when the oxide builds up and clogs the crack or slit.

  2. NACOM - a code for sodium spray fire analysis

    International Nuclear Information System (INIS)

    Rao, P.M.; Kannan, S.E.

    2002-01-01

    Full text: In liquid metal fast breeder reactors (LMFBR), leakage of sodium can result in a spray fire. Because of higher burning rates in droplet form combustion of sodium in spray fire, thermal consequences are more severe than that in a sodium pool fire. The code NACOM was developed for the analysis of sodium spray fires in LMFBRs facilities. The code uses the validated model for estimating the falling droplet burning rates in pre-ignition and vapour phase combustion stages. It uses a distribution system to generate the droplet groups of different diameters that represent the spray. The code requires about 20 input parameters like sodium leak rates, sodium temperature, initial cell conditions like oxygen concentration, temperature and dimensions. NACOM is a validated code based on experiments with sodium inventory up to 650 kg in 0 to 21 % O 2 atmospheres. The paper brings out the salient features of the code along with the sensitivity analysis of the main input parameters like spray volume mean diameter, oxygen concentration etc. based on the results obtained. The limitations of the code and the confidence margins applicable to results obtained are also brought out

  3. A study on post impingement effects of urea-water solution spray on the heated wall of automotive SCR systems

    Science.gov (United States)

    Shahariar, G. M. H.; Wardana, M. K. A.; Lim, O. T.

    2018-04-01

    The post impingement effects of urea-water solution spray on the heated wall of automotive SCR systems was numerically investigated in a constant volume chamber using STAR CCM+ CFD code. The turbulence flow was modelled by realizable k-ε two-layer model together with standard wall function and all y+ treatment was applied along with two-layer approach. The Eulerian-Lagrangian approach was used for the modelling of multi phase flow. Urea water solution (UWS) was injected onto the heated wall for the wall temperature of 338, 413, 473, 503 & 573 K. Spray development after impinging on the heated wall was visualized and measured. Droplet size distribution and droplet evaporation rates were also measured, which are vital parameters for the system performance but still not well researched. Specially developed user defined functions (UDF) are implemented to simulate the desired conditions and parameters. The investigation reveals that wall temperature has a great impact on spray development after impingement, droplet size distribution and evaporation. Increasing the wall temperature leads to longer spray front projection length, smaller droplet size and faster droplet evaporation which are preconditions for urea crystallization reduction. The numerical model and parameters are validated comparing with experimental data.

  4. Engineering a new class of thermal spray nano-based microstructures from agglomerated nanostructured particles, suspensions and solutions: an invited review

    International Nuclear Information System (INIS)

    Fauchais, P; Montavon, G; Lima, R S; Marple, B R

    2011-01-01

    From the pioneering works of McPherson in 1973 who identified nanometre-sized features in thermal spray conventional alumina coatings (using sprayed particles in the tens of micrometres size range) to the most recent and most advanced work aimed at manufacturing nanostructured coatings from nanometre-sized feedstock particles, the thermal spray community has been involved with nanometre-sized features and feedstock for more than 30 years. Both the development of feedstock (especially through cryo-milling, and processes able to manufacture coatings structured at the sub-micrometre or nanometre sizes, such as micrometre-sized agglomerates made of nanometre-sized particles for feedstock) and the emergence of thermal spray processes such as suspension and liquid precursor thermal spray techniques have been driven by the need to manufacture coatings with enhanced properties. These techniques result in two different types of coatings: on the one hand, those with a so-called bimodal structure having nanometre-sized zones embedded within micrometre ones, for which the spray process is similar to that of conventional coatings and on the other hand, sub-micrometre or nanostructured coatings achieved by suspension or solution spraying. Compared with suspension spraying, solution precursor spraying uses molecularly mixed precursors as liquids, avoiding a separate processing route for the preparation of powders and enabling the synthesis of a wide range of oxide powders and coatings. Such coatings are intended for use in various applications ranging from improved thermal barrier layers and wear-resistant surfaces to thin solid electrolytes for solid oxide fuel cell systems, among other numerous applications. Meanwhile these processes are more complex to operate since they are more sensitive to parameter variations compared with conventional thermal spray processes. Progress in this area has resulted from the unique combination of modelling activities, the evolution of

  5. Spray-combustion synthesis: efficient solution route to high-performance oxide transistors.

    Science.gov (United States)

    Yu, Xinge; Smith, Jeremy; Zhou, Nanjia; Zeng, Li; Guo, Peijun; Xia, Yu; Alvarez, Ana; Aghion, Stefano; Lin, Hui; Yu, Junsheng; Chang, Robert P H; Bedzyk, Michael J; Ferragut, Rafael; Marks, Tobin J; Facchetti, Antonio

    2015-03-17

    Metal-oxide (MO) semiconductors have emerged as enabling materials for next generation thin-film electronics owing to their high carrier mobilities, even in the amorphous state, large-area uniformity, low cost, and optical transparency, which are applicable to flat-panel displays, flexible circuitry, and photovoltaic cells. Impressive progress in solution-processed MO electronics has been achieved using methodologies such as sol gel, deep-UV irradiation, preformed nanostructures, and combustion synthesis. Nevertheless, because of incomplete lattice condensation and film densification, high-quality solution-processed MO films having technologically relevant thicknesses achievable in a single step have yet to be shown. Here, we report a low-temperature, thickness-controlled coating process to create high-performance, solution-processed MO electronics: spray-combustion synthesis (SCS). We also report for the first time, to our knowledge, indium-gallium-zinc-oxide (IGZO) transistors having densification, nanoporosity, electron mobility, trap densities, bias stability, and film transport approaching those of sputtered films and compatible with conventional fabrication (FAB) operations.

  6. Solution synthesis of telluride-based nano-barbell structures coated with PEDOT:PSS for spray-printed thermoelectric generators

    Science.gov (United States)

    Bae, Eun Jin; Kang, Young Hun; Jang, Kwang-Suk; Lee, Changjin; Cho, Song Yun

    2016-05-01

    Solution-processable telluride-based heterostructures coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (Te-Bi2Te3/PEDOT:PSS) were synthesized through a solution-phase reaction at low temperatures. The water-based synthesis yielded PEDOT:PSS-coated Te-Bi2Te3 nano-barbell structures with a high Seebeck coefficient that can be stably dispersed in water. These hybrid solutions were deposited onto a substrate by the spray-printing method to prepare thermoelectric generators. The thermoelectric properties of the Te-Bi2Te3/PEDOT:PSS hybrid films were significantly enhanced by a simple acid treatment due to the increased electrical conductivity, and the power factor of those materials can be effectively tuned over a wide range depending on the acid concentration of the treatment. The power factors of the synthesized Te-Bi2Te3/PEDOT:PSS hybrids were optimized to 60.05 μW m-1 K-2 with a Seebeck coefficient of 93.63 μV K-1 and an electrical conductivity of 69.99 S cm-1. The flexible thermoelectric generator fabricated by spray-printing Te-Bi2Te3/PEDOT:PSS hybrid solutions showed an open-circuit voltage of 1.54 mV with six legs at ΔT = 10 °C. This approach presents the potential for realizing printing-processable hybrid thermoelectric materials for application in flexible thermoelectric generators.Solution-processable telluride-based heterostructures coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (Te-Bi2Te3/PEDOT:PSS) were synthesized through a solution-phase reaction at low temperatures. The water-based synthesis yielded PEDOT:PSS-coated Te-Bi2Te3 nano-barbell structures with a high Seebeck coefficient that can be stably dispersed in water. These hybrid solutions were deposited onto a substrate by the spray-printing method to prepare thermoelectric generators. The thermoelectric properties of the Te-Bi2Te3/PEDOT:PSS hybrid films were significantly enhanced by a simple acid treatment due to the increased electrical conductivity, and

  7. High-voltage leak detection of a parenteral proteinaceous solution product packaged in form-fill-seal plastic laminate bags. Part 1. Method development and validation.

    Science.gov (United States)

    Damgaard, Rasmus; Rasmussen, Mats; Buus, Peter; Mulhall, Brian; Guazzo, Dana Morton

    2013-01-01

    In Part 1 of this three-part research series, a leak test performed using high-voltage leak detection (HVLD) technology, also referred to as an electrical conductivity and capacitance leak test, was developed and validated for container-closure integrity verification of a small-volume laminate plastic bag containing an aqueous solution for injection. The sterile parenteral product is the rapid-acting insulin analogue, insulin aspart (NovoRapid®/NovoLog®, by Novo Nordisk A/S, Bagsværd, Denmark). The aseptically filled and sealed package is designed to preserve product sterility through expiry. Method development and validation work incorporated positive control packages with a single hole laser-drilled through the laminate film of each bag. A unique HVLD method characterized by specific high-voltage and potentiometer set points was established for testing bags positioned in each of three possible orientations as they are conveyed through the instrument's test zone in each of two possible directions-resulting in a total of six different test method options. Validation study results successfully demonstrated the ability of all six methods to accurately and reliably detect those packages with laser-drilled holes from 2.5-11.2 μm in nominal diameter. Part 2 of this series will further explore HVLD test results as a function of package seal and product storage variables. The final Part 3 will report the impact of HVLD exposure on product physico-chemical stability. In this Part 1 of a three-part research series, a leak test method based on electrical conductivity and capacitance, called high voltage leak detection (HVLD), was used to find leaks in small plastic bags filled with an insulin pharmaceutical solution for human injection by Novo Nordisk A/S (Bagsværd, Denmark). To perform the test, the package is electrically grounded while being conveyed past an electrode linked to a high-voltage, low-amperage transformer. The instrument measures the current that passes

  8. Controlling Microstructure of Yttria-Stabilized Zirconia Prepared from Suspensions and Solutions by Plasma Spraying with High Feed Rates.

    Czech Academy of Sciences Publication Activity Database

    Mušálek, Radek; Medřický, Jan; Tesař, Tomáš; Kotlan, Jiří; Pala, Zdeněk; Lukáč, František; Illková, Ksenia; Hlína, Michal; Chráska, Tomáš; Sokołowski, P.; Curry, N.

    2017-01-01

    Roč. 26, č. 8 (2017), s. 1787-1803 ISSN 1059-9630 R&D Projects: GA ČR GA15-12145S Institutional support: RVO:61389021 Keywords : hybrid plasma torch * microstructure * solution * precursor spraying * suspension spraying * thermal barrier * coatings (TBCs) * water-stabilized plasma * yttria-stabilized zirconia (YSZ) Subject RIV: JK - Corrosion ; Surface Treatment of Materials OBOR OECD: Coating and films Impact factor: 1.488, year: 2016 https://link.springer.com/ article /10.1007/s11666-017-0622-x

  9. Release mitigation spray safety systems for chemical demilitarization applications.

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, Jonathan; Tezak, Matthew Stephen; Brockmann, John E.; Servantes, Brandon; Sanchez, Andres L.; Tucker, Mark David; Allen, Ashley N.; Wilson, Mollye C.; Lucero, Daniel A.; Betty, Rita G.

    2010-06-01

    Sandia National Laboratories has conducted proof-of-concept experiments demonstrating effective knockdown and neutralization of aerosolized CBW simulants using charged DF-200 decontaminant sprays. DF-200 is an aqueous decontaminant, developed by Sandia National Laboratories, and procured and fielded by the US Military. Of significance is the potential application of this fundamental technology to numerous applications including mitigation and neutralization of releases arising during chemical demilitarization operations. A release mitigation spray safety system will remove airborne contaminants from an accidental release during operations, to protect personnel and limit contamination. Sandia National Laboratories recently (November, 2008) secured funding from the US Army's Program Manager for Non-Stockpile Chemical Materials Agency (PMNSCMA) to investigate use of mitigation spray systems for chemical demilitarization applications. For non-stockpile processes, mitigation spray systems co-located with the current Explosive Destruction System (EDS) will provide security both as an operational protective measure and in the event of an accidental release. Additionally, 'tented' mitigation spray systems for native or foreign remediation and recovery operations will contain accidental releases arising from removal of underground, unstable CBW munitions. A mitigation spray system for highly controlled stockpile operations will provide defense from accidental spills or leaks during routine procedures.

  10. Sodium leak channel, non-selective contributes to the leak current in human myometrial smooth muscle cells from pregnant women.

    Science.gov (United States)

    Reinl, Erin L; Cabeza, Rafael; Gregory, Ismail A; Cahill, Alison G; England, Sarah K

    2015-10-01

    Uterine contractions are tightly regulated by the electrical activity of myometrial smooth muscle cells (MSMCs). These cells require a depolarizing current to initiate Ca(2+) influx and induce contraction. Cationic leak channels, which permit a steady flow of cations into a cell, are known to cause membrane depolarization in many tissue types. Previously, a Gd(3+)-sensitive, Na(+)-dependent leak current was identified in the rat myometrium, but the presence of such a current in human MSMCs and the specific ion channel conducting this current was unknown. Here, we report the presence of a Na(+)-dependent leak current in human myometrium and demonstrate that the Na(+)-leak channel, NALCN, contributes to this current. We performed whole-cell voltage-clamp on fresh and cultured MSMCs from uterine biopsies of term, non-laboring women and isolated the leak currents by using Ca(2+) and K(+) channel blockers in the bath solution. Ohmic leak currents were identified in freshly isolated and cultured MSMCs with normalized conductances of 14.6 pS/pF and 10.0 pS/pF, respectively. The myometrial leak current was significantly reduced (P < 0.01) by treating cells with 10 μM Gd(3+) or by superfusing the cells with a Na(+)-free extracellular solution. Reverse transcriptase PCR and immunoblot analysis of uterine biopsies from term, non-laboring women revealed NALCN messenger RNA and protein expression in the myometrium. Notably, ∼90% knockdown of NALCN protein expression with lentivirus-delivered shRNA reduced the Gd(3+)-sensitive leak current density by 42% (P < 0.05). Our results reveal that NALCN, in part, generates the leak current in MSMCs and provide the basis for future research assessing NALCN as a potential molecular target for modulating uterine excitability. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Advances in small zero-leak valves point to better nuclear power-plant reliability

    Energy Technology Data Exchange (ETDEWEB)

    Eacott, K B; Kin, J C; Hotta, Y [Dresser Japan, Ltd.

    1978-04-01

    In the selection of small valves less than two inches used for nuclear power plants, sufficient consideration must be given to the reliability to radioactive material, the easy operability, and the significant function, especially zero leak. These valves are classified into bellows and diaphragm seal types which must satisfy zero leak, 4000 cycles life test and good maintainability. Welded bellows, formed bellows, and metal diaphragms are actually used for these requirements. The construction of these types are shown. The requirements and principal specifications for these small valves are explained, and some examples are given. These zero leak valves are installed in reactor coolant loop system, borated water from B. A. system, pressurizer instrument system, containment spray system, high head system and off gas system for PWRS, and main steam line system, diesel generator cooling water system, re-circulation system, clean up water system, etc. for BWRS.

  12. Preparation of cellulose based microspheres by combining spray coagulating with spray drying.

    Science.gov (United States)

    Wang, Qiao; Fu, Aiping; Li, Hongliang; Liu, Jingquan; Guo, Peizhi; Zhao, Xiu Song; Xia, Lin Hua

    2014-10-13

    Porous microspheres of regenerated cellulose with size in range of 1-2 μm and composite microspheres of chitosan coated cellulose with size of 1-3 μm were obtained through a two-step spray-assisted approach. The spray coagulating process must combine with a spray drying step to guarantee the formation of stable microspheres of cellulose. This approach exhibits the following two main virtues. First, the preparation was performed using aqueous solution of cellulose as precursor in the absence of organic solvent and surfactant; Second, neither crosslinking agent nor separated crosslinking process was required for formation of stable microspheres. Moreover, the spray drying step also provided us with the chance to encapsulate guests into the resultant cellulose microspheres. The potential application of the cellulose microspheres acting as drug delivery vector has been studied in two PBS (phosphate-buffered saline) solution with pH values at 4.0 and 7.4 to mimic the environments of stomach and intestine, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Spray pyrolysis process for preparing superconductive films

    International Nuclear Information System (INIS)

    Hsu, H.M.; Yee, I.Y.

    1991-01-01

    This paper describes a spray pyrolysis method for preparing thin superconductive film. It comprises: preparing a spray pyrolysis solution comprising Bi,Sr,Ca and Cu metals in a solvent; heating a substrate to a first temperature; spraying the solution onto the heated substrate to form a film thereon; heating the film and substrate to a second temperature of about 700 degrees-825 degrees C, the second temperature being higher than the first temperature; heating the film and substrate to a third temperature of about 870 degrees-890 degrees C to melt the film; once the film and substrate reach the third temperature, further heat treating the film and substrate; cooling the film and substrate to ambient temperature. This patent also describes a spray pyrolysis method for preparing thin superconductive films. It comprises: preparing a spray pyrolysis solution comprising Bi, Ca and Cu metals and fluxing agent in a solvent; heating a substrate to a first temperature; spraying the solution onto the heated substrate to form a film thereon; heating the film and substrate to a second temperature about 700 degrees-825 degrees C, the second temperature being higher than the first temperature; heating the film and substrate at a third temperature about 840 degrees-860 degrees C; and cooling the film and substrate to ambient temperature

  14. A numerical approach for the study of large sodium spray fires and its application for SPX1

    International Nuclear Information System (INIS)

    Varet, T.; Leroy, B.; Barthez, M.; Malet, J.C.

    1996-01-01

    For the original design of SUPER-PHENIX, only pool fires were analysed for secondary sodium because these were thought to be the most likely. However, after the sodium spray fire at the solar plant of ALMERIA, an analysis of the consequences of secondary spray fire was undertaken. According to the French Safety Authority, the most penalizing cases of sodium leak and fire must be taken into account for each type of consequences, up to the complete rupture of a main secondary pipe. The experimental data available were mainly based on sodium flowrates in the range of ten kilograms per second, which are far below the leak flowrates obtained in case of a complete rupture of a main secondary pipe, i.e. several tons of sodium per second during a short time interval; moreover, it was obviously not possible to perform sodium tests with such high flowrate conditions. Consequently a complete methodology for the prediction of the behaviour of large sodium spray fires has been developed: the two-dimensional code PULSAR, which solves the two phase flow Navier-Stokes equations with source terms of mass and energy, is first used to evaluate the physical behaviour of a spray of sodium droplets in a cell in diverse conditions and thus to determine the burning rate. This last value is then used as data in the FEUMIX code in which other phenomena such as the dynamic response of pressure relief systems are described, in order to determine the pressure transient in the cell. This approach has been successfully tested using the experimental data available from past and recent tests, particularly the high flowrates tests IGNA 3602 and IGNA 3604. This numerical approach has been applied to the analysis of the consequences of postulated large sodium leaks in SUPER-PHENIX and allowed us to justify the hypotheses used to design the protective measures implemented on the plant, and thus the demonstration of safety with regard to large sodium leaks. (author)

  15. Influence of solution deposition rate on properties of V_2O_5 thin films deposited by spray pyrolysis technique

    International Nuclear Information System (INIS)

    Abd–Alghafour, N. M.; Ahmed, Naser M.; Hassan, Zai; Mohammad, Sabah M.

    2016-01-01

    Vanadium oxide (V_2O_5) thin films were deposited on glass substrates by using a cost-efficient spray pyrolysis technique. The films were grown at 350° through thermal decomposition of VCl_3 in deionized water with different solution spray rates. The high resolution X-ray diffraction results revealed the formation of nanocrystalline films having orthorhombic structures with preferential orientation along (101) direction. The spray rate influenced the surface morphology and crystallite size of the films. The crystallite size was found to increase whereas the micro-strain was decreased by increasing the spray deposition rates. The increase in crystallite size and decrease in the macrostrain resulted in an improvement in the films’ crystallinity. The UV-Visible spectroscopy analysis indicated that the average transmittance of all films lies in the range 75-80 %. The band gap of V_2O_5 film was decreased from 2.65 to 2.46 eV with increase of the spray deposition rate from 5 ml/min to 10 ml/min. first, second, and third level headings (first level heading).

  16. SINGLE-SHELL TANKS LEAK INTEGRITY ELEMENTS/SX FARM LEAK CAUSES AND LOCATIONS - 12127

    Energy Technology Data Exchange (ETDEWEB)

    VENETZ TJ; WASHENFELDER D; JOHNSON J; GIRARDOT C

    2012-01-25

    Washington River Protection Solutions, LLC (WRPS) developed an enhanced single-shell tank (SST) integrity project in 2009. An expert panel on SST integrity was created to provide recommendations supporting the development of the project. One primary recommendation was to expand the leak assessment reports (substitute report or LD-1) to include leak causes and locations. The recommendation has been included in the M-045-9IF Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) as one of four targets relating to SST leak integrity. The 241-SX Farm (SX Farm) tanks with leak losses were addressed on an individual tank basis as part of LD-1. Currently, 8 out of 23 SSTs that have been reported to having a liner leak are located in SX Farm. This percentage was the highest compared to other tank farms which is why SX Farm was analyzed first. The SX Farm is comprised of fifteen SSTs built 1953-1954. The tanks are arranged in rows of three tanks each, forming a cascade. Each of the SX Farm tanks has a nominal I-million-gal storage capacity. Of the fifteen tanks in SX Farm, an assessment reported leak losses for the following tanks: 241-SX-107, 241-SX-108, 241-SX-109, 241-SX-111, 241-SX-112, 241-SX-113, 241-SX-114 and 241-SX-115. The method used to identify leak location consisted of reviewing in-tank and ex-tank leak detection information. This provided the basic data identifying where and when the first leaks were detected. In-tank leak detection consisted of liquid level measurement that can be augmented with photographs which can provide an indication of the vertical leak location on the sidewall. Ex-tank leak detection for the leaking tanks consisted of soil radiation data from laterals and drywells near the tank. The in-tank and ex-tank leak detection can provide an indication of the possible leak location radially around and under the tank. Potential leak causes were determined using in-tank and ex-tank information that is not directly related to

  17. Single-Shell Tanks Leak Integrity Elements/ SX Farm Leak Causes and Locations - 12127

    Energy Technology Data Exchange (ETDEWEB)

    Girardot, Crystal [URS- Safety Management Solutions, Richland, Washington 99352 (United States); Harlow, Don [ELR Consulting Richland, Washington 99352 (United States); Venetz, Theodore; Washenfelder, Dennis [Washington River Protection Solutions, LLC Richland, Washington 99352 (United States); Johnson, Jeremy [U.S. Department of Energy, Office of River Protection Richland, Washington 99352 (United States)

    2012-07-01

    Washington River Protection Solutions, LLC (WRPS) developed an enhanced single-shell tank (SST) integrity project in 2009. An expert panel on SST integrity was created to provide recommendations supporting the development of the project. One primary recommendation was to expand the leak assessment reports (substitute report or LD-1) to include leak causes and locations. The recommendation has been included in the M-045-91F Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) as one of four targets relating to SST leak integrity. The 241-SX Farm (SX Farm) tanks with leak losses were addressed on an individual tank basis as part of LD-1. Currently, 8 out of 23 SSTs that have been reported to having a liner leak are located in SX Farm. This percentage was the highest compared to other tank farms which is why SX Farm was analyzed first. The SX Farm is comprised of fifteen SSTs built 1953-1954. The tanks are arranged in rows of three tanks each, forming a cascade. Each of the SX Farm tanks has a nominal 1-million-gal storage capacity. Of the fifteen tanks in SX Farm, an assessment reported leak losses for the following tanks: 241-SX-107, 241-SX-108, 241-SX-109, 241-SX- 111, 241-SX-112, 241-SX-113, 241-SX-114 and 241-SX-115. The method used to identify leak location consisted of reviewing in-tank and ex-tank leak detection information. This provided the basic data identifying where and when the first leaks were detected. In-tank leak detection consisted of liquid level measurement that can be augmented with photographs which can provide an indication of the vertical leak location on the sidewall. Ex-tank leak detection for the leaking tanks consisted of soil radiation data from laterals and dry-wells near the tank. The in-tank and ex-tank leak detection can provide an indication of the possible leak location radially around and under the tank. Potential leak causes were determined using in-tank and ex-tank information that is not directly related to

  18. Design, characterization, and aerosolization of organic solution advanced spray-dried moxifloxacin and ofloxacin dipalmitoylphosphatidylcholine (DPPC) microparticulate/nanoparticulate powders for pulmonary inhalation aerosol delivery

    Science.gov (United States)

    Duan, Jinghua; Vogt, Frederick G; Li, Xiaojian; Hayes, Don; Mansour, Heidi M

    2013-01-01

    The aim of this study was to design and develop respirable antibiotics moxifloxacin (MOXI) hydrochloride and ofloxacin (OFLX) microparticles and nanoparticles, and multifunctional antibiotics particles with or without lung surfactant 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) for targeted dry powder inhalation delivery as a pulmonary nanomedicine. Particles were rationally designed and produced by advanced spray-drying particle engineering from an organic solution in closed mode (no water) from dilute solution. Scanning electron microscopy indicated that these particles had both optimal particle morphology and surface morphology, and the particle size distributions were suitable for pulmonary delivery. Comprehensive and systematic physicochemical characterization and in vitro aerosol dispersion performance revealed significant differences between these two fluoroquinolone antibiotics following spray drying as drug aerosols and as cospray-dried antibiotic drug: DPPC aerosols. Fourier transform infrared spectroscopy and confocal Raman microspectroscopy were employed to probe composition and interactions in the solid state. Spray-dried MOXI was rendered noncrystalline (amorphous) following organic solution advanced spray drying. This was in contrast to spray-dried OFLX, which retained partial crystallinity, as did OFLX:DPPC powders at certain compositions. Aerosol dispersion performance was conducted using inertial impaction with a dry powder inhaler device approved for human use. The present study demonstrates that the use of DPPC offers improved aerosol delivery of MOXI as cospray-dried microparticulate/nanoparticulate powders, whereas residual partial crystallinity influenced aerosol dispersion of OFLX and most of the compositions of OFLX:DPPC inhalation powders. PMID:24092972

  19. Leak rate models and leak detection

    International Nuclear Information System (INIS)

    1992-01-01

    Leak detection may be carried out by a number of detection systems, but selection of the systems must be carefully adapted to the fluid state and the location of the leak in the reactor coolant system. Computer programs for the calculation of leak rates contain different models to take into account the fluid state before its entrance into the crack, and they have to be verified by experiments; agreement between experiments and calculations is generally not satisfactory for very small leak rates resulting from narrow cracks or from a closing bending moment

  20. High-Voltage Leak Detection of a Parenteral Proteinaceous Solution Product Packaged in Form-Fill-Seal Plastic Laminate Bags. Part 3. Chemical Stability and Visual Appearance of a Protein-Based Aqueous Solution for Injection as a Function of HVLD Exposure.

    Science.gov (United States)

    Rasmussen, Mats; Damgaard, Rasmus; Buus, Peter; Guazzo, Dana Morton

    2013-01-01

    This Part 3 of this three-part research series reports the impact of high-voltage leak detection (HVLD) exposure on the physico-chemical stability of the packaged product. The product, intended for human administration by injection, is an aqueous solution formulation of the rapid acting insulin analogue, insulin aspart (NovoRapid®/NovoLog®) by Novo Nordisk A/S, Bagsværd, Denmark. The package is a small-volume form-fill-seal plastic laminate bag. Product-packages exposed to HVLD were compared to unexposed product after storage for 9 months at recommended storage conditions of 5 ± 3 °C. No differences in active ingredient or degradation products assays were noted. No changes in any other stability indicating parameter results were observed. This report concludes this three-part series. Part 1 documented HVLD method development and validation work. Part 2 explored the impact of various package material, package temperature, and package storage conditions on HVLD test results. Detection of leaks in the bag seal area was investigated. In conclusion, HVLD is reported to be a validatable leak test method suitable for rapid, nondestructive container-closure integrity evaluation of the subject product-package. In Part 1 of this three-part series, a leak test method based on electrical conductivity and capacitance, also called high-voltage leak detection (HVLD), was proven to find hole leaks in small plastic bags filled with a solution of insulin aspart intended for human injection (NovoRapid®/NovoLog® by Novo Nordisk A/S, Bagsværd, Denmark). In Part 2, the ability of the HVLD method to find other types of package leaks was tested, and the impact of package material and product storage temperature on HVLD results was explored. This final Part 3 checked how well the packaged protein drug solution maintained its potency after HVLD exposure over 9 months of storage under long-term stability conditions. Results showed that HVLD caused no harm to the product.

  1. On the possibilities for efficient simulation of leak rates through SG tubes

    International Nuclear Information System (INIS)

    Sorsek, I.; Cizelj, L.

    1995-01-01

    In this paper, the problem of predicting excessive leak rates through the through wall cracks in tubes at the tube - tube support plate intersections is discussed in some detail. Basically, we are able to define the leak rate through an individual defect. On the steam generator level, which actually means the sum of all individual leak rates, a new approach is introduced. The main characteristic of the new approach is seeking for a probability of exceeding the allowable leak rate rather than estimating more or less conservative highest expected leak rate value. This however introduces extensive computational effort which practically prevents the use of direct Monte Carlo simulations. Some possibilities to reduce the computational effort are discussed and their preliminary results compared. Also, some exact solutions were found and compared with numerical solutions achieved with the first order reliability method. Directions for future work in this important topic are given. (author)

  2. Evaluation of methodologies for the calculation of leak rates for pressure retaining components with crack-like leaks

    International Nuclear Information System (INIS)

    Sievers, Juergen; Heckmann, Klaus; Blaesius, Christoph

    2015-06-01

    For the demonstration of break preclusion for pressure retaining components in nuclear power plants, the nuclear safety standard KTA 3206 determines also the requirements for the leak-before-break verification. For this procedure, it has to be ensured that a wall-penetrating crack is subcritical with respect to instable growth, and that the resulting leakage under stationary operation conditions can be detected by a leak detection system. Within the scope of the project 3613R01332 analyses with respect to conservative estimates of the leak rates in case of detections regarding break preclusion were performed by means of leak rate models being available at GRS. For this purpose, conservative assumptions in the procedure were quantified by comparative calculations concerning selected leak rate experiments and the requirements regarding the determination of leak rates indicated in the KTA 3206 were verified and specified. Moreover, the models were extended and relevant recommendations for the calculation procedure were developed. During the investigations of leak rate tests the calculation methods were validated, qualified by means of both examples indicated in KTA 3206 and applied to a postulated leak accident in the cooling circuit of a PWR. For the calculation of leak rates several simplified solution methods which are included in the GRS program WinLeck were applied, and for the simulation of a leak accident the large-scale programs ANSYS Mechanical and ATHLET (thermohydraulics program developed by GRS) were used. When applying simplified methods for the calculation of leak rates using the limiting curve for the friction factor which has been derived during the project and which is included in the KTA 3206 attention has to be paid to the fact that in case of small flow lengths the entrance loss can dominate compared to the friction loss. However, the available data do not suffice in order to make a quantitative statement with respect to limits of applicability

  3. Hydrazine-Free Solution-Deposited CuIn(S,Se)2 Solar Cells by Spray Deposition of Metal Chalcogenides.

    Science.gov (United States)

    Arnou, Panagiota; van Hest, Maikel F A M; Cooper, Carl S; Malkov, Andrei V; Walls, John M; Bowers, Jake W

    2016-05-18

    Solution processing of semiconductors, such as CuInSe2 and its alloys (CIGS), can significantly reduce the manufacturing costs of thin film solar cells. Despite the recent success of solution deposition approaches for CIGS, toxic reagents such as hydrazine are usually involved, which introduce health and safety concerns. Here, we present a simple and safer methodology for the preparation of high-quality CuIn(S, Se)2 absorbers from metal sulfide solutions in a diamine/dithiol mixture. The solutions are sprayed in air, using a chromatography atomizer, followed by a postdeposition selenization step. Two different selenization methods are explored resulting in power conversion efficiencies of up to 8%.

  4. A rich solution spray as a refining method in a small capacity, single effect, solar assisted absorption machine with the pair NH3/H2O: Experimental results

    International Nuclear Information System (INIS)

    Mendes, L.F.; Collares-Pereira, M.; Ziegler, F.

    2007-01-01

    Ammonia vapour refining is a common procedure in ammonia-water absorption machines. A solar assisted single effect absorption machine that uses the pair ammonia-water was developed and tested. Its desorber has a built-in adiabatic refining column constituted by a rich solution spray. The refining method proved its feasibility. The spray provided a more or less constant ammonia vapour enrichment of about 1% which is enough for the working temperature ranges of this type of machine. It was also verified that the refining effect of the spray is almost independent of the refrigerant vapour and solution mass flow rates

  5. Influence of solution deposition rate on properties of V{sub 2}O{sub 5} thin films deposited by spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Abd–Alghafour, N. M., E-mail: na2013bil@gmail.com [Iraqi Ministry of Education, Anbar (Iraq); Ahmed, Naser M.; Hassan, Zai; Mohammad, Sabah M. [Nano-Optoelectronics Research and Technology Laboratory, School of Physics, University Sains Malaysia,11800 Penang (Malaysia)

    2016-07-19

    Vanadium oxide (V{sub 2}O{sub 5}) thin films were deposited on glass substrates by using a cost-efficient spray pyrolysis technique. The films were grown at 350° through thermal decomposition of VCl{sub 3} in deionized water with different solution spray rates. The high resolution X-ray diffraction results revealed the formation of nanocrystalline films having orthorhombic structures with preferential orientation along (101) direction. The spray rate influenced the surface morphology and crystallite size of the films. The crystallite size was found to increase whereas the micro-strain was decreased by increasing the spray deposition rates. The increase in crystallite size and decrease in the macrostrain resulted in an improvement in the films’ crystallinity. The UV-Visible spectroscopy analysis indicated that the average transmittance of all films lies in the range 75-80 %. The band gap of V{sub 2}O{sub 5} film was decreased from 2.65 to 2.46 eV with increase of the spray deposition rate from 5 ml/min to 10 ml/min. first, second, and third level headings (first level heading).

  6. Development & characterization of alumina coating by atmospheric plasma spraying

    Science.gov (United States)

    Sebastian, Jobin; Scaria, Abyson; Kurian, Don George

    2018-03-01

    Ceramic coatings are applied on metals to prevent them from oxidation and corrosion at room as well as elevated temperatures. The service environment, mechanisms of protection, chemical and mechanical compatibility, application method, control of coating quality and ability of the coating to be repaired are the factors that need to be considered while selecting the required coating. The coatings based on oxide materials provides high degree of thermal insulation and protection against oxidation at high temperatures for the underlying substrate materials. These coatings are usually applied by the flame or plasma spraying methods. The surface cleanliness needs to be ensured before spraying. Abrasive blasting can be used to provide the required surface roughness for good adhesion between the substrate and the coating. A pre bond coat like Nickel Chromium can be applied on to the substrate material before spraying the oxide coating to avoid chances of poor adhesion between the oxide coating and the metallic substrate. Plasma spraying produces oxide coatings of greater density, higher hardness, and smooth surface finish than that of the flame spraying process Inert gas is often used for generation of plasma gas so as to avoid the oxidation of the substrate material. The work focuses to develop, characterize and optimize the parameters used in Al2O3 coating on transition stainless steel substrate material for minimizing the wear rate and maximizing the leak tightness using plasma spray process. The experiment is designed using Taguchi’s L9 orthogonal array. The parameters that are to be optimized are plasma voltage, spraying distance and the cooling jet pressure. The characterization techniques includes micro-hardness and porosity tests followed by Grey relational analysis of the results.

  7. Intraoperative leak testing has no correlation with leak after laparoscopic sleeve gastrectomy.

    Science.gov (United States)

    Sethi, Monica; Zagzag, Jonathan; Patel, Karan; Magrath, Melissa; Somoza, Eduardo; Parikh, Manish S; Saunders, John K; Ude-Welcome, Aku; Schwack, Bradley F; Kurian, Marina S; Fielding, George A; Ren-Fielding, Christine J

    2016-03-01

    Staple line leak is a serious complication of sleeve gastrectomy. Intraoperative methylene blue and air leak tests are routinely used to evaluate for leak; however, the utility of these tests is controversial. We hypothesize that the practice of routine intraoperative leak testing is unnecessary during sleeve gastrectomy. A retrospective cohort study was designed using a prospectively collected database of seven bariatric surgeons from two institutions. All patients who underwent sleeve gastrectomy from March 2012 to November 2014 were included. The performance of intraoperative leak testing and the type of test (air or methylene blue) were based on surgeon preference. Data obtained included BMI, demographics, comorbidity, presence of intraoperative leak test, result of test, and type of test. The primary outcome was leak rate between the leak test (LT) and no leak test (NLT) groups. SAS version 9.4 was used for univariate and multivariate analyses. A total of 1550 sleeve gastrectomies were included; most were laparoscopic (99.8%), except for one converted and two open cases. Routine intraoperative leak tests were performed in 1329 (85.7%) cases, while 221 (14.3%) did not have LTs. Of the 1329 cases with LTs, there were no positive intraoperative results. Fifteen (1%) patients developed leaks, with no difference in leak rate between the LT and NLT groups (1 vs. 1%, p = 0.999). After adjusting for baseline differences between the groups with a propensity analysis, the observed lack of association between leak and intraoperative leak test remained. In this cohort, leaks presented at a mean of 17.3 days postoperatively (range 1-67 days). Two patients with staple line leaks underwent repeat intraoperative leak testing at leak presentation, and the tests remained negative. Intraoperative leak testing has no correlation with leak due to laparoscopic sleeve gastrectomy and is not predictive of the later development of staple line leak.

  8. Contribution of electro-spray mass spectrometry to the study of the organic species and metal-ligand complexes in solution

    International Nuclear Information System (INIS)

    Berthon, L.; Piveteau, B.

    2000-01-01

    Electro-spray ionization mass spectrometry (ESI-MS) has quickly become a versatile method of qualitative analysis of a wide variety of species in solution. This technique (with positive and negative ionization modes) is used to analyze organic solutions in the frame of the DIAMEX process. Degraded solvent had been studied without any preliminary sample treatment (separation or derivation) and neutral complexes 'uranyl nitrate - malonamide' had been observed. (authors)

  9. Optimization of the Automated Spray Layer-by-Layer Technique for Thin Film Deposition

    Science.gov (United States)

    2010-06-01

    air- pumped spray-paint cans 17,18 to fully automated systems using high pressure gas .7’ 19 This work uses the automated spray system previously...spray solutions were delivered by ultra high purity nitrogen gas (AirGas) regulated to 25psi, except when examining air pressure effects . The PAH solution...polyelectrolyte solution feed tube, the resulting Venturi effect causes the liquid solution to be drawn up into the airbrush nozzle, where it is

  10. Spray drying of liquid radioactive wastes

    International Nuclear Information System (INIS)

    Abrams, R.F.; Monat, J.P.

    1984-01-01

    Full scale performance tests of a Koch spray dryer were conducted on simulated liquid radioactive waste streams. The liquid feeds simulated the solutions that result from radwaste incineration of DAW an ion exchange resins, as well as evaporator bottoms. The integration of the spray dryer into a complete system is discussed

  11. Effects of laser remelting on microstructures and immersion corrosion performance of arc sprayed Al coating in 3.5% NaCl solution

    Science.gov (United States)

    Sun, Ze; Zhang, Donghui; Yan, Baoxu; Kong, Dejun

    2018-02-01

    An arc sprayed aluminum (Al) coating on S355 steel was processed using a laser remelting (LR). The microstructures, chemical element composition, and phases of the obtained Al coating were analyzed using a field mission scanning electronic microscope (FESEM), energy dispersive spectrometer (EDS), and X-ray diffractometer (XRD), respectively, and the residual stresses were measured using an X-ray diffraction stress tester. The immersion corrosion tests and potentiodynamic polarization of Al coating in 3.5% NaCl solution were performed to investigate the effects of LR on its immersion corrosion behaviors, and the corrosion mechanism of Al coating was also discussed. The results show that the arc sprayed Al coating is composed of Al phase, while that by LR is composed of Al-Fe and AlO4FeO6 phases, and the porosities and cracks in the arc sprayed Al coating are eliminated by LR, The residual stress of arc sprayed Al coating is -5.6 ± 18 MPa, while that after LR is 137.9 ± 12 MPa, which deduces the immersion corrosion resistance of Al coating. The corrosion mechanism of arc sprayed Al coating is pitting corrosion and crevice corrosion, while that by LR is uniform corrosion and pitting corrosion. The corrosion potential of arc sprayed Al coating by LR shifts positively, which improves its immersion corrosion resistance.

  12. Fabrication of Semiconducting Methylammonium Lead Halide Perovskite Particles by Spray Technology

    Science.gov (United States)

    Ahmadian-Yazdi, Mohammad-Reza; Eslamian, Morteza

    2018-01-01

    In this "nano idea" paper, three concepts for the preparation of methylammonium lead halide perovskite particles are proposed, discussed, and tested. The first idea is based on the wet chemistry preparation of the perovskite particles, through the addition of the perovskite precursor solution to an anti-solvent to facilitate the precipitation of the perovskite particles in the solution. The second idea is based on the milling of a blend of the perovskite precursors in the dry form, in order to allow for the conversion of the precursors to the perovskite particles. The third idea is based on the atomization of the perovskite solution by a spray nozzle, introducing the spray droplets into a hot wall reactor, so as to prepare perovskite particles, using the droplet-to-particle spray approach (spray pyrolysis). Preliminary results show that the spray technology is the most successful method for the preparation of impurity-free perovskite particles and perovskite paste to deposit perovskite thin films. As a proof of concept, a perovskite solar cell with the paste prepared by the sprayed perovskite powder was successfully fabricated.

  13. Fabrication of Semiconducting Methylammonium Lead Halide Perovskite Particles by Spray Technology.

    Science.gov (United States)

    Ahmadian-Yazdi, Mohammad-Reza; Eslamian, Morteza

    2018-01-10

    In this "nano idea" paper, three concepts for the preparation of methylammonium lead halide perovskite particles are proposed, discussed, and tested. The first idea is based on the wet chemistry preparation of the perovskite particles, through the addition of the perovskite precursor solution to an anti-solvent to facilitate the precipitation of the perovskite particles in the solution. The second idea is based on the milling of a blend of the perovskite precursors in the dry form, in order to allow for the conversion of the precursors to the perovskite particles. The third idea is based on the atomization of the perovskite solution by a spray nozzle, introducing the spray droplets into a hot wall reactor, so as to prepare perovskite particles, using the droplet-to-particle spray approach (spray pyrolysis). Preliminary results show that the spray technology is the most successful method for the preparation of impurity-free perovskite particles and perovskite paste to deposit perovskite thin films. As a proof of concept, a perovskite solar cell with the paste prepared by the sprayed perovskite powder was successfully fabricated.

  14. Leak detection : Principles and practice

    International Nuclear Information System (INIS)

    Rama Rao, V.V.K.

    1981-01-01

    Principles of leak detection are explained and various aspects of leak detection techniques and leak detectors are reviewed. The review covers: units for leaks and leak tightness, classification of leaks, timing of leak testing, designing for ease of leak testing of any job, methods of leak detection, their ranges of application and limitations, leak detectors, response time of leak test, minimum detectable concentration of search gas during leak tests, and validity of leak tests. Helium mass spectrometer type leak detector and technique are described in detail. Recent improvements in leak detectors and techniques, particularly mass spectrometer leak detectors using gases other than helium (e.g. hydrogen, argon) are also covered in the review. (M.G.B.)

  15. Stoichiometry and superconductive properties of YBaCuO films deposited by spray pyrolysis

    International Nuclear Information System (INIS)

    Conde-Gallardo, A.; Falcony, C.; Ortiz, A.

    1994-01-01

    The dependence of the stoichiometry and the superconducting characteristics of YBaCuO films deposited by spray pyrolysis on the spraying solution composition and the deposition conditions is reported. It has been found that a proper optimization of the starting materials concentration in the spraying solution results in superconducting films with zero resistance temperature of 91 K and a transition to superconducting state within a 3 K range. X-ray diffraction and resistance vs temperature measurements have been used to monitor the crystal composition and the conductive characteristics of the films as a function of the spraying solution composition and the deposition parameters

  16. Anastomotic leak detection by electrolyte electrical resistance.

    Science.gov (United States)

    DeArmond, Daniel T; Cline, Adam M; Johnson, Scott B

    2010-08-01

    To characterize a new method of postoperative gastrointestinal leak detection based on electrical resistance changes due to extravasated electrolyte contrast. Postoperative gastrointestinal leak results in increased patient morbidity, mortality, and hospital costs that can be mitigated by early diagnosis. A sensitive and specific diagnostic test that could be performed at the bedside has the potential to shorten the time to diagnosis and thereby improve the quality of treatment. Anaesthetized rats underwent celiotomy and creation of a 5-mm gastrotomy. In experimental animals, electrical resistance changes were measured with a direct current ohmmeter after the introduction of 5 cc of 23.4% NaCl electrolyte solution via gavage and measured with a more sensitive alternating current ohmmeter after the gavage of 1-5 cc of 0.9% NaCl. Comparison was made to negative controls and statistical analysis was performed. Leakage from the gastrotomy induced by as little as 1 cc of gavage-delivered 0.9% NaCl contrast solution was detectable as a statistically significant drop in electrical resistance when compared to results from negative controls. Electrical resistance change associated with electrolyte-gated leak detection is highly sensitive and specific and has the potential to be rapidly translated into clinical settings.

  17. Mapping urban pipeline leaks: Methane leaks across Boston

    International Nuclear Information System (INIS)

    Phillips, Nathan G.; Ackley, Robert; Crosson, Eric R.; Down, Adrian; Hutyra, Lucy R.; Brondfield, Max; Karr, Jonathan D.; Zhao Kaiguang; Jackson, Robert B.

    2013-01-01

    Natural gas is the largest source of anthropogenic emissions of methane (CH 4 ) in the United States. To assess pipeline emissions across a major city, we mapped CH 4 leaks across all 785 road miles in the city of Boston using a cavity-ring-down mobile CH 4 analyzer. We identified 3356 CH 4 leaks with concentrations exceeding up to 15 times the global background level. Separately, we measured δ 13 CH 4 isotopic signatures from a subset of these leaks. The δ 13 CH 4 signatures (mean = −42.8‰ ± 1.3‰ s.e.; n = 32) strongly indicate a fossil fuel source rather than a biogenic source for most of the leaks; natural gas sampled across the city had average δ 13 CH 4 values of −36.8‰ (±0.7‰ s.e., n = 10), whereas CH 4 collected from landfill sites, wetlands, and sewer systems had δ 13 CH 4 signatures ∼20‰ lighter (μ = −57.8‰, ±1.6‰ s.e., n = 8). Repairing leaky natural gas distribution systems will reduce greenhouse gas emissions, increase consumer health and safety, and save money. Highlights: ► We mapped 3356 methane leaks in Boston. ► Methane leaks in Boston carry an isotopic signature of pipeline natural gas. ► Replacing failing gas pipelines will provide safety, environmental, and economic benefits. - We identified 3356 methane leaks in Boston, with isotopic characteristics consistent with pipeline natural gas.

  18. LSPRAY-IV: A Lagrangian Spray Module

    Science.gov (United States)

    Raju, M. S.

    2012-01-01

    LSPRAY-IV is a Lagrangian spray solver developed for application with parallel computing and unstructured grids. It is designed to be massively parallel and could easily be coupled with any existing gas-phase flow and/or Monte Carlo Probability Density Function (PDF) solvers. The solver accommodates the use of an unstructured mesh with mixed elements of either triangular, quadrilateral, and/or tetrahedral type for the gas flow grid representation. It is mainly designed to predict the flow, thermal and transport properties of a rapidly vaporizing spray. Some important research areas covered as a part of the code development are: (1) the extension of combined CFD/scalar-Monte- Carlo-PDF method to spray modeling, (2) the multi-component liquid spray modeling, and (3) the assessment of various atomization models used in spray calculations. The current version contains the extension to the modeling of superheated sprays. The manual provides the user with an understanding of various models involved in the spray formulation, its code structure and solution algorithm, and various other issues related to parallelization and its coupling with other solvers.

  19. Gas-leak localization using distributed ultrasonic sensors

    Science.gov (United States)

    Huseynov, Javid; Baliga, Shankar; Dillencourt, Michael; Bic, Lubomir; Bagherzadeh, Nader

    2009-03-01

    We propose an ultrasonic gas leak localization system based on a distributed network of sensors. The system deploys highly sensitive miniature Micro-Electro-Mechanical Systems (MEMS) microphones and uses a suite of energy-decay (ED) and time-delay of arrival (TDOA) algorithms for localizing a source of a gas leak. Statistical tools such as the maximum likelihood (ML) and the least squares (LS) estimators are used for approximating the source location when closed-form solutions fail in the presence of ambient background nuisance and inherent electronic noise. The proposed localization algorithms were implemented and tested using a Java-based simulation platform connected to four or more distributed MEMS microphones observing a broadband nitrogen leak from an orifice. The performance of centralized and decentralized algorithms under ED and TDOA schemes is analyzed and compared in terms of communication overhead and accuracy in presence of additive white Gaussian noise (AWGN).

  20. The feasibility study of hot cell decontamination by the PFC spray method

    International Nuclear Information System (INIS)

    Hui-Jun Won; Chong-Hun Jung; Jei-Kwon Moon

    2008-01-01

    The characteristics of per-fluorocarbon compounds (PFC) are colorless, non-toxic, easily vaporized and nonflammable. Also, some of them are liquids of a high density, low surface tension, low latent heat and low specific heat. These particular chemical and physical properties of fluoro-organic compounds permit their use in very different fields such as electronics, medicine, tribology, nuclear and material science. The Sonatol process was developed under a contract with the DOE. The Sonatol process uses an ultrasonic agitation in a PFC solution that contains a fluorinated surfactant to remove radioactive particles from surfaces. Filtering the suspended particles allows the solutions to be reused indefinitely. They applied the Sonatol process to the decontamination of a heterogeneous legacy Pu-238 waste that exhibited an excessive hydrogen gas generation, which prevents a transportation of such a waste to a Waste Isolation Pilot Plant. Korea Atomic Energy Research Institute (KAERI) is developing dry decontamination technologies applicable to a decontamination of a highly radioactive area loosely contaminated with radioactive particles. This contamination has occurred as a result of an examination of a post-irradiated material or the development of the DUPIC process. The dry decontamination technologies developed are the carbon dioxide pellet spray method and the PFC spray method. As a part of the project, PFC ultrasonic decontamination technology was developed in 2004. The PFC spray decontamination method which is based on the test results of the PFC ultrasonic method has been under development since 2005. The developed PFC spray decontamination equipment consists of four modules (spray, collection, filtration and distillation). Vacuum cup of the collection module gathers the contaminated PFC solution, then the solution is moved to the filtration module and it is recycled. After a multiple recycling of the spent PFC solution, it is purified in the distillation

  1. Method of forming a leak proof plasma sprayed interconnection layer on an electrode of an electrochemical cell

    Science.gov (United States)

    Kuo, Lewis J. H.; Vora, Shailesh D.

    1995-01-01

    A dense, substantially gas-tight, electrically conductive interconnection layer is formed on an electrode structure of an electrochemical cell by: (A) providing an electrode structure; (B) forming on a selected portion of the electrode surface, an interconnection layer having the general formula La.sub.1-x M.sub.x Cr.sub.1-y N.sub.y O.sub.3, where M is a dopant selected from the group of Ca, Sr, Ba, and mixtures thereof, and where N is a dopant selected from the group of Mg, Co, Ni, Al, and mixtures thereof, and where x and y are each independently about 0.075-0.25, by thermally spraying, preferably plasma arc spraying, a flux added interconnection spray powder, preferably agglomerated, the flux added powder comprising flux particles, preferably including dopant, preferably (CaO).sub.12. (Al.sub.2 O.sub.3).sub.7 flux particles including Ca and Al dopant, and LaCrO.sub.3 interconnection particles, preferably undoped LaCrO.sub.3, to form a dense and substantially gas-tight interconnection material bonded to the electrode structure by a single plasma spraying step; and, (C) heat treating the interconnection layer at from about 1200.degree. to 1350.degree. C. to further densify and heal the micro-cracks and macro-cracks of the thermally sprayed interconnection layer. The result is a substantially gas-tight, highly doped, electrically conductive interconnection material bonded to the electrode structure. The electrode structure can be an air electrode, and a solid electrolyte layer can be applied to the unselected portion of the air electrode, and further a fuel electrode can be applied to the solid electrolyte, to form an electrochemical cell for generation of electrical power.

  2. Analysis of SX farm leak histories - Historical leak model (HLM)

    International Nuclear Information System (INIS)

    Fredenburg, E.A.

    1998-01-01

    This report uses readily available historical information to better define the volume, chemical composition, and Cs-137/Sr-90 amounts for leaks that have occurred in the past for tanks SX-108, SX-109, SX-111, and SX-112. In particular a Historical Leak Model (HLM) is developed that is a month by month reconciliation of tank levels, fill records, and calculated boil-off rates for these tanks. The HLM analysis is an independent leak estimate that reconstructs the tank thermal histories thereby deriving each tank's evaporative volume loss and by difference, its unaccounted losses as well. The HLM analysis was meant to demonstrate the viability of its approach, not necessarily to establish the HLM leak estimates as being definitive. Past leak estimates for these tanks have invariably resorted to soil wetting arguments but the extent of soil contaminated by each leak has always been highly uncertain. There is also a great deal of uncertainty with the HLM that was not quantified in this report, but will be addressed later. These four tanks (among others) were used from 1956 to 1975 for storage of high-level waste from the Redox process at Hanford. During their operation, tank waste temperatures were often as high as 150 C (300 F), but were more typically around 130 C. The primary tank cooling was by evaporation of tank waste and therefore periodic replacement of lost volume with water was necessary to maintain each tank's inventory. This active reflux of waste resulted in very substantial turnovers in tank inventory as well as significant structural degradation of these tanks. As a result of the loss of structural integrity, each of these tanks leaked during their active periods of operation. Unfortunately, the large turnover in tank volume associated with their reflux cooling has made a determination of leak volumes very difficult. During much of these tanks operational histories, inventory losses because of evaporative cooling could have effectively masked any volume

  3. Leak detection/verification

    Energy Technology Data Exchange (ETDEWEB)

    Krhounek, V.; Zdarek, J.; Pecinka, L. [Nuclear Research Institute, Rez (Czech Republic)

    1997-04-01

    Loss of coolant accident (LOCA) experiments performed as part of a Leak Before Break (LBB) analysis are very briefly summarized. The aim of these experiments was to postulate the leak rates of the coolant. Through-wall cracks were introduced into pipes by fatigue cycling and hydraulically loaded in a test device. Measurements included coolant pressure and temperature, quantity of leaked coolant, displacement of a specimen, and acoustic emission. Small cracks were plugged with particles in the coolant during testing. It is believed that plugging will have no effect in cracks with leak rates above 35 liters per minute. The leak rate safety margin of 10 is sufficient for cracks in which the leak rate is more than 5 liters per minute.

  4. Remote leak localization approach for fusion machines

    International Nuclear Information System (INIS)

    Durocher, Au.; Bruno, V.; Chantant, M.; Gargiulo, L.; Gherman, T.; Hatchressian, J.-C.; Houry, M.; Le, R.; Mouyon, D.

    2013-01-01

    120 °C), “ppm” traces of helium or water have been measured. To improve these first promising results, a new test-bed called ROVE (remote operation vacuum equipment) has been set up in 2012 to qualify leak sensors and remote operation. A list of concepts has been set out from contacts with manufacturers and laboratories. For sniffing solutions it includes laser absorption measurement, mass spectrometer analyses and vibrating quartz. For embeddable concepts thermal conductivity and capacitive sensors are considered. Choice of concepts to detect water or helium traces is based on major criteria, such as weight, high sensibility and fast response time and recovery time. They also have to be operational under primary vacuum conditions or atmospheric pressure and from ambient temperature to 60 °C

  5. Remote leak localization approach for fusion machines

    Energy Technology Data Exchange (ETDEWEB)

    Durocher, Au., E-mail: aurelien.durocher@cea.fr [CEA-IRFM, F-13108 Saint Paul-Lez-Durance (France); Bruno, V.; Chantant, M.; Gargiulo, L. [CEA-IRFM, F-13108 Saint Paul-Lez-Durance (France); Gherman, T. [Floralis UJF Filiale, F-38610 Gières (France); Hatchressian, J.-C.; Houry, M.; Le, R.; Mouyon, D. [CEA-IRFM, F-13108 Saint Paul-Lez-Durance (France)

    2013-10-15

    120 °C), “ppm” traces of helium or water have been measured. To improve these first promising results, a new test-bed called ROVE (remote operation vacuum equipment) has been set up in 2012 to qualify leak sensors and remote operation. A list of concepts has been set out from contacts with manufacturers and laboratories. For sniffing solutions it includes laser absorption measurement, mass spectrometer analyses and vibrating quartz. For embeddable concepts thermal conductivity and capacitive sensors are considered. Choice of concepts to detect water or helium traces is based on major criteria, such as weight, high sensibility and fast response time and recovery time. They also have to be operational under primary vacuum conditions or atmospheric pressure and from ambient temperature to 60 °C.

  6. Calibration of a leak detection spectrometer; Calibration d'un spectrometre detecteur de fuites

    Energy Technology Data Exchange (ETDEWEB)

    Geller, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    This paper describes a study of the possible methods for calibrating a leak detection spectrometer, and the estimation of outputs from the leaks is considered. With this in mind the question of sensitivity of leak detection is tackled on a very general level; first the sensitivity of the isolated instrument is determined, and then the sensitivity of an instrument connected to an installation where leaks may be suspected. Finally, practical solutions are proposed. (author) [French] Dans cet article, nous etudions les methodes possibles de calibration d'un spectrometre detecteur de fuites et nous envisageons l'evaluation des debits de fuites trouves. Pour cela, nous abordons la notion de sensibilite de la detection de fuite sur un plan tres general; d'abord nous determinons la sensibilite de l'appareil isole, ensuite la sensibilite d'un appareil connecte sur une installation ou l'on cherche les fuites. Enfin, nous preconisons des solutions pratiques. (auteur)

  7. LSPRAY-V: A Lagrangian Spray Module

    Science.gov (United States)

    Raju, M. S.

    2015-01-01

    LSPRAY-V is a Lagrangian spray solver developed for application with unstructured grids and massively parallel computers. It is mainly designed to predict the flow, thermal and transport properties of a rapidly vaporizing spray encountered over a wide range of operating conditions in modern aircraft engine development. It could easily be coupled with any existing gas-phase flow and/or Monte Carlo Probability Density Function (PDF) solvers. The manual provides the user with an understanding of various models involved in the spray formulation, its code structure and solution algorithm, and various other issues related to parallelization and its coupling with other solvers. With the development of LSPRAY-V, we have advanced the state-of-the-art in spray computations in several important ways.

  8. Detection of heavy-water leaks in nuclear reactors : a novel method

    International Nuclear Information System (INIS)

    Murthy, M.S.; Gor, M.K.

    2002-01-01

    Technical Physics and Prototype Engineering Division, BARC has designed, developed and produced several high sensitivity mass spectrometer helium leak detectors over a period of two decades. Sometimes back, when there was a problem of detecting heavy water leaks in situ in one of the nuclear power reactors of the Department of Atomic Energy, it was referred to this division for a technical solution. After discussing with the site engineers, the various problems involved in the on-line detection of heavy water leaks especially near the end fittings of the coolant assemblies, a novel method of leak detection was developed. Some of the salient features of the method and the results obtained in the laboratory tests are given in this paper. (author)

  9. Polydisperse effects in jet spray flames

    Science.gov (United States)

    Weinberg, Noam; Greenberg, J. Barry

    2018-01-01

    A laminar jet polydisperse spray diffusion flame is analysed mathematically for the first time using an extension of classical similarity solutions for gaseous jet flames. The analysis enables a comparison to be drawn between conditions for flame stability or flame blow-out for purely gaseous flames and for spray flames. It is found that, in contrast to the Schmidt number criteria relevant to gas flames, droplet size and initial spray polydispersity play a critical role in determining potential flame scenarios. Some qualitative agreement for lift-off height is found when comparing predictions of the theory and sparse independent experimental evidence from the literature.

  10. Transient analysis of intermittent multijet sprays

    Energy Technology Data Exchange (ETDEWEB)

    Panao, Miguel R.O.; Moreira, Antonio Luis N. [Universidade Tecnica de Lisboa, IN, Center for Innovation, Technology and Policy Research, Instituto Superior Tecnico, Lisboa (Portugal); Durao, Diamantino G. [Universidade Lusiada, Lisboa (Portugal)

    2012-07-15

    This paper analyzes the transient characteristics of intermittent sprays produced by the single-point impact of multiple cylindrical jets. The aim is to perform a transient analysis of the intermittent atomization process to study the effect of varying the number of impinging jets in the hydrodynamic mechanisms of droplet formation. The results evidence that hydrodynamic mechanisms underlying the physics of ligament fragmentation in 2-impinging jets sprays also apply to sprays produced with more than 2 jets during the main period of injection. Ligaments detaching from the liquid sheet, as well as from its bounding rim, have been identified and associated with distinct droplet clusters, which become more evident as the number of impinging jets increases. Droplets produced by detached ligaments constitute the main spray, and their axial velocity becomes more uniformly distributed with 4-impinging jets because of a delayed ligament fragmentation. Multijet spray dispersion patterns are geometric depending on the number of impinging jets. Finally, an analysis on the Weber number of droplets suggests that multijet sprays are more likely to deposit on interposed surfaces, thus becoming a promising and competitive atomization solution for improving spray cooling. (orig.)

  11. Y2O3-MgO Nano-Composite Synthesized by Plasma Spraying and Thermal Decomposition of Solution Precursors

    Science.gov (United States)

    Muoto, Chigozie Kenechukwu

    This research aims to identify the key feedstock characteristics and processing conditions to produce Y2O3-MgO composite coatings with high density and hardness using solution precursor plasma spray (SPPS) and suspension plasma spray (SPS) processes, and also, to explore the phenomena involved in the production of homogenized nano-composite powders of this material system by thermal decomposition of solution precursor mixtures. The material system would find potential application in the fabrication of components for optical applications such as transparent windows. It was shown that a lack of major endothermic events during precursor decomposition and the resultant formation of highly dense particles upon pyrolysis are critical precursor characteristics for the deposition of dense and hard Y2O3-MgO coatings by SPPS. Using these principles, a new Y2O3-MgO precursor solution was developed, which yielded a coating with Vickers hardness of 560 Hv. This was a considerable improvement over the hardness of the coatings obtained using conventional solution precursors, which was as low as 110 Hv. In the thermal decomposition synthesis process, binary solution precursor mixtures of: yttrium nitrate (Y[n]) or yttrium acetate (Y[a]), with magnesium nitrate (Mg[n]) or magnesium acetate (Mg[a]) were used in order to study the effects of precursor chemistry on the structural characteristics of the resultant Y2O3-MgO powders. The phase domains were coarse and distributed rather inhomogeneously in the materials obtained from the Y[n]Mg[n] and Y[a]Mg[a] mixtures; finer and more homogeneously-distributed phase domains were obtained for ceramics produced from the Y[a]Mg[n] and Y[n]Mg[a] mixtures. It was established that these phenomena were related to the thermal characteristics for the decomposition of the precursors and their effect on phase separation during oxide crystallization. Addition of ammonium acetate to the Y[n[Mg[n] mixture changed the endothermic process to exothermic

  12. Experiments on leak-selfwastage and leak-propagation

    International Nuclear Information System (INIS)

    Voss, J.; Vagt, P.; Westenbrugge, J.K. van; Joziasse, J.

    1984-01-01

    During the last years a considerable number of selfwastage experiments with small leaks of different shape and size and for different ferritic materials (2 1/4% Cr - and 12% Cr-steel) were performed by TNO and by INTERATOM, using several sodium test facilities. Many fabrication-methods of artificial micro-leaks were applied and examined. Selfplugging-, selfwastage- and reopening-effects were observed and evaluated during different time periods and under various test conditions. The main results will be discussed. Concerning the leak propagation program of INTERATOM, the first series of experiments was carried out this year. A short status report and some first results will be given. (author)

  13. Characterization of Amorphous and Co-Amorphous Simvastatin Formulations Prepared by Spray Drying

    Directory of Open Access Journals (Sweden)

    Goedele Craye

    2015-12-01

    Full Text Available In this study, spray drying from aqueous solutions, using the surface-active agent sodium lauryl sulfate (SLS as a solubilizer, was explored as a production method for co-amorphous simvastatin–lysine (SVS-LYS at 1:1 molar mixtures, which previously have been observed to form a co-amorphous mixture upon ball milling. In addition, a spray-dried formulation of SVS without LYS was prepared. Energy-dispersive X-ray spectroscopy (EDS revealed that SLS coated the SVS and SVS-LYS particles upon spray drying. X-ray powder diffraction (XRPD and differential scanning calorimetry (DSC showed that in the spray-dried formulations the remaining crystallinity originated from SLS only. The best dissolution properties and a “spring and parachute” effect were found for SVS spray-dried from a 5% SLS solution without LYS. Despite the presence of at least partially crystalline SLS in the mixtures, all the studied formulations were able to significantly extend the stability of amorphous SVS compared to previous co-amorphous formulations of SVS. The best stability (at least 12 months in dry conditions was observed when SLS was spray-dried with SVS (and LYS. In conclusion, spray drying of SVS and LYS from aqueous surfactant solutions was able to produce formulations with improved physical stability for amorphous SVS.

  14. Characterization of Amorphous and Co-Amorphous Simvastatin Formulations Prepared by Spray Drying.

    Science.gov (United States)

    Craye, Goedele; Löbmann, Korbinian; Grohganz, Holger; Rades, Thomas; Laitinen, Riikka

    2015-12-03

    In this study, spray drying from aqueous solutions, using the surface-active agent sodium lauryl sulfate (SLS) as a solubilizer, was explored as a production method for co-amorphous simvastatin-lysine (SVS-LYS) at 1:1 molar mixtures, which previously have been observed to form a co-amorphous mixture upon ball milling. In addition, a spray-dried formulation of SVS without LYS was prepared. Energy-dispersive X-ray spectroscopy (EDS) revealed that SLS coated the SVS and SVS-LYS particles upon spray drying. X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) showed that in the spray-dried formulations the remaining crystallinity originated from SLS only. The best dissolution properties and a "spring and parachute" effect were found for SVS spray-dried from a 5% SLS solution without LYS. Despite the presence of at least partially crystalline SLS in the mixtures, all the studied formulations were able to significantly extend the stability of amorphous SVS compared to previous co-amorphous formulations of SVS. The best stability (at least 12 months in dry conditions) was observed when SLS was spray-dried with SVS (and LYS). In conclusion, spray drying of SVS and LYS from aqueous surfactant solutions was able to produce formulations with improved physical stability for amorphous SVS.

  15. An assessment of thermal spray coating technologies for high temperature corrosion protection

    International Nuclear Information System (INIS)

    Heath, G.R.; Heimgartner, P.; Gustafsson, S.; Irons, G.; Miller, R.

    1997-01-01

    The use of thermally sprayed coatings in combating high temperature corrosion continues to grow in the major industries of chemical, waste incineration, power generation and pulp and paper. This has been driven partially by the development of corrosion resistant alloys, improved knowledge and quality in the thermal spray industry and continued innovation in thermal spray equipment. There exists today an extensive range of thermal spray process options, often with the same alloy solution. In demanding corrosion applications it is not sufficient to just specify alloy and coating method. For the production of reliable coatings the whole coating production envelope needs to be considered, including alloy selection, spray parameters, surface preparation, base metal properties, heat input etc. Combustion, arc-wire, plasma, HVOF and spray+fuse techniques are reviewed and compared in terms of their strengths and limitations to provide cost-effective solutions for high temperature corrosion protection. Arc wire spraying, HP/HVOF and spray+fuse are emerging as the most promising techniques to optimise both coating properties and economic/practical aspects. (orig.)

  16. Water Pipeline Monitoring and Leak Detection using Flow Liquid Meter Sensor

    Science.gov (United States)

    Rahmat, R. F.; Satria, I. S.; Siregar, B.; Budiarto, R.

    2017-04-01

    Water distribution is generally installed through underground pipes. Monitoring the underground water pipelines is more difficult than monitoring the water pipelines located on the ground in open space. This situation will cause a permanent loss if there is a disturbance in the pipeline such as leakage. Leaks in pipes can be caused by several factors, such as the pipe’s age, improper installation, and natural disasters. Therefore, a solution is required to detect and to determine the location of the damage when there is a leak. The detection of the leak location will use fluid mechanics and kinematics physics based on harness water flow rate data obtained using flow liquid meter sensor and Arduino UNO as a microcontroller. The results show that the proposed method is able to work stably to determine the location of the leak which has a maximum distance of 2 metres, and it’s able to determine the leak location as close as possible with flow rate about 10 litters per minute.

  17. Ultrasensitive leak detection

    International Nuclear Information System (INIS)

    Winkelman, C.R.; Davidson, H.G.

    1978-01-01

    The objective of this investigation was to develop a method of detecting leaks to a sensitivity of 1.0 x 10 -13 std/cm 3 /s in vacuum devices and to develop a qualifiable standard leak to provide system calibration at this leak rate. The development work demonstrated that minimum detectable leak rates of 6.5 x 10 -14 std/cm 3 /s and 5.5 x 10 -15 std/cm 3 /s are possible for respective analog and digital measurement modes

  18. Optimal sensor placement for leak location in water distribution networks using genetic algorithms.

    Science.gov (United States)

    Casillas, Myrna V; Puig, Vicenç; Garza-Castañón, Luis E; Rosich, Albert

    2013-11-04

    This paper proposes a new sensor placement approach for leak location in water distribution networks (WDNs). The sensor placement problem is formulated as an integer optimization problem. The optimization criterion consists in minimizing the number of non-isolable leaks according to the isolability criteria introduced. Because of the large size and non-linear integer nature of the resulting optimization problem, genetic algorithms (GAs) are used as the solution approach. The obtained results are compared with a semi-exhaustive search method with higher computational effort, proving that GA allows one to find near-optimal solutions with less computational load. Moreover, three ways of increasing the robustness of the GA-based sensor placement method have been proposed using a time horizon analysis, a distance-based scoring and considering different leaks sizes. A great advantage of the proposed methodology is that it does not depend on the isolation method chosen by the user, as long as it is based on leak sensitivity analysis. Experiments in two networks allow us to evaluate the performance of the proposed approach.

  19. Optimal Sensor Placement for Leak Location in Water Distribution Networks Using Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Luis E. Garza-Castañón

    2013-11-01

    Full Text Available This paper proposes a new sensor placement approach for leak location in water distribution networks (WDNs. The sensor placement problem is formulated as an integer optimization problem. The optimization criterion consists in minimizing the number of non-isolable leaks according to the isolability criteria introduced. Because of the large size and non-linear integer nature of the resulting optimization problem, genetic algorithms (GAs are used as the solution approach. The obtained results are compared with a semi-exhaustive search method with higher computational effort, proving that GA allows one to find near-optimal solutions with less computational load. Moreover, three ways of increasing the robustness of the GA-based sensor placement method have been proposed using a time horizon analysis, a distance-based scoring and considering different leaks sizes. A great advantage of the proposed methodology is that it does not depend on the isolation method chosen by the user, as long as it is based on leak sensitivity analysis. Experiments in two networks allow us to evaluate the performance of the proposed approach.

  20. Optimal Sensor Placement for Leak Location in Water Distribution Networks Using Genetic Algorithms

    Science.gov (United States)

    Casillas, Myrna V.; Puig, Vicenç; Garza-Castañón, Luis E.; Rosich, Albert

    2013-01-01

    This paper proposes a new sensor placement approach for leak location in water distribution networks (WDNs). The sensor placement problem is formulated as an integer optimization problem. The optimization criterion consists in minimizing the number of non-isolable leaks according to the isolability criteria introduced. Because of the large size and non-linear integer nature of the resulting optimization problem, genetic algorithms (GAs) are used as the solution approach. The obtained results are compared with a semi-exhaustive search method with higher computational effort, proving that GA allows one to find near-optimal solutions with less computational load. Moreover, three ways of increasing the robustness of the GA-based sensor placement method have been proposed using a time horizon analysis, a distance-based scoring and considering different leaks sizes. A great advantage of the proposed methodology is that it does not depend on the isolation method chosen by the user, as long as it is based on leak sensitivity analysis. Experiments in two networks allow us to evaluate the performance of the proposed approach. PMID:24193099

  1. Measuring Spray Droplet Size from Agricultural Nozzles Using Laser Diffraction

    Science.gov (United States)

    Fritz, Bradley K.; Hoffmann, W. Clint

    2016-01-01

    When making an application of any crop protection material such as an herbicide or pesticide, the applicator uses a variety of skills and information to make an application so that the material reaches the target site (i.e., plant). Information critical in this process is the droplet size that a particular spray nozzle, spray pressure, and spray solution combination generates, as droplet size greatly influences product efficacy and how the spray moves through the environment. Researchers and product manufacturers commonly use laser diffraction equipment to measure the spray droplet size in laboratory wind tunnels. The work presented here describes methods used in making spray droplet size measurements with laser diffraction equipment for both ground and aerial application scenarios that can be used to ensure inter- and intra-laboratory precision while minimizing sampling bias associated with laser diffraction systems. Maintaining critical measurement distances and concurrent airflow throughout the testing process is key to this precision. Real time data quality analysis is also critical to preventing excess variation in the data or extraneous inclusion of erroneous data. Some limitations of this method include atypical spray nozzles, spray solutions or application conditions that result in spray streams that do not fully atomize within the measurement distances discussed. Successful adaption of this method can provide a highly efficient method for evaluation of the performance of agrochemical spray application nozzles under a variety of operational settings. Also discussed are potential experimental design considerations that can be included to enhance functionality of the data collected. PMID:27684589

  2. Assessment of spray deposition with water-sensitive paper cards

    Science.gov (United States)

    Spatial distributions of spray droplets discharged from an airblast sprayer, were sampled on pairs of absorbent paper (AP) and water-sensitive paper (WSP) targets at several distances from the sprayer. Spray solutions, containing a fluorescent tracer, were discharged from two size nozzles to achiev...

  3. Thermodynamic consequences of sodium leaks and fires in reactor containments

    International Nuclear Information System (INIS)

    Cherdron, W.; Jordan, S.

    1989-01-01

    In the technical and design concept of containment systems of sodium cooled breeder reactors due consideration must be given to the fact, that sodium penetration through leakages leads to sodium fires. The temperature and pressure rise caused by sodium fires makes it indispensable to analyze these accidents to be able to asses the safety of the whole system. To study the thermodynamic consequences of sodium leaks and fires, a long series of experiments on pool fires, spray fires and combined fires has been performed in the FAUNA-facility. In the pool fire experiments the pool area has been varied between 2 m 2 and 12 m 2 , with up to 500 kg of sodium at 500 deg. C inlet temperature. Burning rates between 20 and 40 kg Na/m 2 /h, depending on the particular conditions, can be stated for such types of fires. Combined fires, simulating a leakage through an insulation, have been investigated using a special sodium outlet 6 m above a 12 m 2 burning pan. The sodium flow ejection rate in these experiments covered the range of 50 up to 710 gr Na/sec, the maximum total amount of sodium released into the FAUNA vessel was 810 kg. The consequences of combined fires cover the range between pool fires and spray fires. The sodium spray fires were performed using a sodium spray system (150 liters of sodium at 500 deg. C and up to 6 bars overpressure), installed in the FAUNA containment, ejecting the sodium vertically upwards towards the impact plate at the top of the containment. In a series of experiments the spray nozzles have been varied from circular holes to sharp and rough edged slits, the flow rate covered the range from 0.8 kg Na/sec up to 56 Na/sec. It has been found that the nozzle design influences somewhat the course of the pressure increase, but the maximum overpressure is mainly determined by the sodium flow rate and the amount of sodium ejected. (author)

  4. Local Intraarterial Thrombolysis: In Vitro Comparison Between Automatic and Manual Pulse-Spray Infusion

    International Nuclear Information System (INIS)

    Froelich, Jens J.; Freymann, Christina; Hoppe, Martin; Thiel, Thomas; Wagner, H. Joachim; Barth, Klemens H.; Klose, Klaus J.

    1996-01-01

    Purpose: Manual and automatic pulse-spray infusion techniques are compared in vitro to evaluate the efficacy of thrombolysis and the distribution of urokinase and saline solution within thrombus using a pulse-spray catheter. Methods: A pulse-spray catheter was introduced into a human thrombus within a stenotic flow model. Automatic and manual pulsed infusion of urokinase and automatic pulsed infusion of saline solution were compared. To quantify the efficacy of thrombolysis, pressure gradients were recorded proximal and distal to the thrombus and during the course of infusion. Distribution of infused urokinase was assessed radiographically. Results: The fastest and most homogeneous dissolution of the thrombus was achieved with automatic pulsed infusion of urokinase, shown by decreasing transthrombotic pressure gradients (p < 0.001, Wilcoxon, matched pairs). Manual pulsed infusion of urokinase or saline solution resulted in inhomogeneous thrombus dissolution and delayed thrombolysis. Conclusion: Application of automatic pulse-spray injectors seems beneficial for more effective and homogeneous intraarterial pulse-spray thrombolysis when compared with conventional manual pulsed technique

  5. Effects of Sea-Surface Waves and Ocean Spray on Air-Sea Momentum Fluxes

    Science.gov (United States)

    Zhang, Ting; Song, Jinbao

    2018-04-01

    The effects of sea-surface waves and ocean spray on the marine atmospheric boundary layer (MABL) at different wind speeds and wave ages were investigated. An MABL model was developed that introduces a wave-induced component and spray force to the total surface stress. The theoretical model solution was determined assuming the eddy viscosity coefficient varied linearly with height above the sea surface. The wave-induced component was evaluated using a directional wave spectrum and growth rate. Spray force was described using interactions between ocean-spray droplets and wind-velocity shear. Wind profiles and sea-surface drag coefficients were calculated for low to high wind speeds for wind-generated sea at different wave ages to examine surface-wave and ocean-spray effects on MABL momentum distribution. The theoretical solutions were compared with model solutions neglecting wave-induced stress and/or spray stress. Surface waves strongly affected near-surface wind profiles and sea-surface drag coefficients at low to moderate wind speeds. Drag coefficients and near-surface wind speeds were lower for young than for old waves. At high wind speeds, ocean-spray droplets produced by wind-tearing breaking-wave crests affected the MABL strongly in comparison with surface waves, implying that wave age affects the MABL only negligibly. Low drag coefficients at high wind caused by ocean-spray production increased turbulent stress in the sea-spray generation layer, accelerating near-sea-surface wind. Comparing the analytical drag coefficient values with laboratory measurements and field observations indicated that surface waves and ocean spray significantly affect the MABL at different wind speeds and wave ages.

  6. Study on water leak-tightness of small leaks on a 1 inch cylinder valve

    International Nuclear Information System (INIS)

    Miyazawa, T.; Kasai, Y.; Inabe, N.; Aritomi, M.

    2002-01-01

    Practical thresholds for water leak-tightness of small leaks were determined by experimentation. Measurements for small leak samples were taken of air leakage rates and water leakage rates for identical leak samples in order to identify parameters that influence water leak-tightness threshold. Four types of leaks were evaluated: a fine wire inserted in an O-ring seal, a glass capillary tube, a stainless steel orifice, and a scratched valve stem on a 1 inch UF 6 cylinder valve. Experimental results demonstrated that the key parameter for water leak-tightness is the opening size of the leak hole. The maximum allowable hole size to achieve water leak-tightness ranged from 10 to 20 μm in diameter in this study. Experimental results with 1 inch UF 6 cylinder valve samples demonstrated that the acceptance criteria for preshipment leakage test, 1x10 -3 ref-cm 3 .s -1 , as prescribed in ANSI N14.5 is an appropriate value from the point of view of water leak-tightness for enriched UF 6 packages. The mechanism of water leak-tightness is plugging by tiny particles existing in water. The water used in experiments in this study contained far fewer particles than in water assumed to be encountered under accident conditions of transport. Therefore, the water leak-tightness threshold determined in this study is a conservative value in a practical evaluation. (author)

  7. Leaking Fuel Impacts and Practices

    International Nuclear Information System (INIS)

    Hozer, Zoltan; Szabo, Peter; Somfai, Barbara; Cherubini, Marco; Aldworth, Robin; Waeckel, Nicolas; Delorme, Tim; Dickson, Raymond; Fujii, Hajime; Rey Gayo, Jose Maria; Grant, Wade; Gorzel, Andreas; Hellwig, Christian; Kamimura, Katsuichiro; Sugiyama, Tomoyuki; Klouzal, Jan; Miklos, Marek; Nagase, Fumihisa; Nilsson, Marcus; Petit, Marc; Richards, Stuart; Lundqvist Saleh, Tobias; Stepniewski, Marek; Sim, Ki Seob; ); Rehacek, Radomir; Kissane, Martin; )

    2014-01-01

    The impact of leaking fuel rods on the operation of nuclear power plants and the practices of handling leaking fuel has been reviewed by the CSNI Working Group on Fuel Safety in order to promote a better understanding on the handling of leaking fuel in power reactors, as well as to discuss and review the current practices in member countries to help in decisions on the specification of reactor operation conditions with leaking fuel rods and on the handling of leaking fuel after removal from reactor. Experts from 15 countries provided data on the handling of leaking fuel in PWR, BWR, VVER and PHWR reactor types. The review covered the operation of NPP reactors with leaking fuel, wet and dry storage and transport of leaking assemblies. The methods and applied instruments to identify leaking fuel assemblies and the repair of them were addressed in the review. Special attention was paid to the activity release from leaking rods in the reactor and under storage conditions. The consideration of leaking fuel in safety analyses on core behaviour during postulated accidents was also discussed in the review. The main conclusions of the review pointed out that the activity release from leaking fuel rods in the reactor can be handled by technological systems, or in case of failure of too many rods the reactor can be shutdown to minimize activity release. Under accident conditions and operational transients the leaking rods may produce coolant activity concentration peaks. The storage of spent leaking fuel is normally characterised by moderate release of radionuclides from the fuel. The power plants apply limits for activity concentration to limit the amount of leaking rods in the core. In different countries, the accident analyses take into consideration the potential release from leaking fuel rods in design basis accidents in different ways. Some power plants apply special tools for handling and repair of leaking assemblies and rods. The leaking rods are stored together with

  8. Development of cold sprayed Cu coating for canister

    International Nuclear Information System (INIS)

    Kim, Hyung Jun; Kang, Yoon Ha

    2010-01-01

    Cold sprayed Cu deposition was studied for the application of outer part of canister for high level nuclear waste. Five commercially available pure Cu powders were analyzed and sprayed by high pressure cold spray system. Electrochemical corrosion test using potentiostat in 3.5% NaCl solution was conducted as well as microstructural analysis including hardness and oxygen content measurements. Overall evaluation of corrosion performance of cold sprayed Cu deposition is inferior to forged and extruded Cu plates, but some of Cu depositions are comparable to Cu plates. The simulated corrosion test in 200m underground cave is still in progress. The effect of cold spray process parameters was also studied and the results show that the type of nozzle is the most important other than powder feed rate, spray distance, and scan speed. 1/10 scale miniature of canister was manufactured confirming that the production of full scale canister is possible

  9. A mathematical model for leak location and leak area determination in pipeline networks

    Directory of Open Access Journals (Sweden)

    Oyedokun O.I.

    2013-01-01

    Full Text Available Prompt leak location and leak area determination in oil and gas pipeline installations is an indispensable approach to controlling petroleum products wastages in pipes. However, there is an evident lack of literature information on this subject. In this paper, we modelled leak location detection and leak area determination in pipes by applying two methodologies and gave an illustrative example using simulated data with the aid of Matlab. A comparison of these two approaches resulted in an error of 6.24%, suggesting that the closer the leak is to the measurement station, the lower will be the time interval between two successive waves that will pass through the leak and get to the measurement station. The relationship between the pipe area and coefficient of reflection is parabolic. This contribution is valuable to pipeline engineers in the economic control of leaks.

  10. Corrosion characteristics of thermal sprayed coating of stainless alloys in chloride solution; Taishoku gokin yosha himaku no enkabutsu yoekichu ni okeru fushoku tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, T. [Ajinomoto Co. Inc., Tokyo (Japan); Ishikawa, K. [Tokyo Metallikon Co. Ltd., Tokyo (Japan); Kitamura, Y. [Kitamura Technical Consultant Office, Kanagawa (Japan)

    1994-12-15

    With an objective to develop a thermal sprayed coating of environment interruption type that can be sprayed at sites, electrochemical discussions, SEM observation, and EPMA surface analysis were performed on corrosion characteristics in chloride solution of coatings of SUS 304, 316 and Hastelloy C thermally sprayed onto test pieces made of structural steel SS400, as well as the effect of improvement in corrosion resistance by means of a coating reforming treatment. The following conclusions were obtained: the degradation in corrosion resistance of the coatings is attributable to increase in anodic solubility due to appearance of innumerable crevices as a result of deposited particles forming porous structure and due to drop of Cr content in the matrix caused by generation of oxides on the surface of the crevices, by which the corrosion progresses in the form of crevice corrosion; and denseness of the passive coating is lost on the surface of the deposited particles, accelerating the cathodic reaction. A suitable means that could be used practically in chloride solution would be a method to use a material with less crevice susceptibility such as Hastelloy C as a base material, and seal the crevice structure with epoxy resin, etc. 7 refs., 10 figs., 3 tabs.

  11. Small sodium-to-gas leak behavior in relation to LMFBR leak detection system design

    International Nuclear Information System (INIS)

    Hopenfeld, J.; Taylor, G.R.; James, L.A.

    1976-01-01

    Various aspects of sodium-to-gas leaks which must be considered in the design of leak detection systems for LMFBR's are discussed. Attention is focused primarily on small, weeping type leaks. Corrosion rates of steels in fused sodium hydroxide and corrosion damage observed at the site of small leaks lead to the conclusion that the sodium-gas reaction products could attack the primary hot leg piping at rates up to 0.08 mils per hour. Based on theoretical considerations of the corrosion mechanism and on visual observations of pipe topography following small sodium leak tests, it is concluded that pipe damage will be manifested by the formation of small detectable leaks prior to the appearance of larger leaks. The case for uniform pipe corrosion along the pipe circumference or along a vertical section of the pipe is also examined. Using a theoretical model for the gravity flow of sodium and reaction products along the pipe surface and a mass transport controlled corrosion process, it is shown that below sodium leak rates of about 30 g/hr for the primary piping corrosion damage will not extend beyond one radius distance from the leak site. A method of estimating the time delay between the initiation of such leaks and the development of a larger leak due to increased pipe stresses resulting from corrosion is presented

  12. Impact of nanocrystal spray deposition on inorganic solar cells.

    Science.gov (United States)

    Townsend, Troy K; Yoon, Woojun; Foos, Edward E; Tischler, Joseph G

    2014-05-28

    Solution-synthesized inorganic cadmium telluride nanocrystals (∼4 nm; 1.45 eV band gap) are attractive elements for the fabrication of thin-film-based low-cost photovoltaic (PV) devices. Their encapsulating organic ligand shell enables them to be easily dissolved in organic solvents, and the resulting solutions can be spray-cast onto indium-tin oxide (ITO)-coated glass under ambient conditions to produce photoactive thin films of CdTe. Following annealing at 380 °C in the presence of CdCl2(s) and evaporation of metal electrode contacts (glass/ITO/CdTe/Ca/Al), Schottky-junction PV devices were tested under simulated 1 sun conditions. An improved PV performance was found to be directly tied to control over the film morphology obtained by the adjustment of spray parameters such as the solution concentration, delivery pressure, substrate distance, and surface temperature. Higher spray pressures produced thinner layers (spray-cast Schottky devices rivaled those prepared by conventional spin-coating, showing Jsc = 14.6 ± 2.7 mA cm(-2), Voc = 428 ± 11 mV, FF = 42.8 ± 1.4%, and Eff. = 2.7 ± 0.5% under 1 sun illumination. This optimized condition of CdTe spray deposition was then applied to heterojunction devices (ITO/CdTe/ZnO/Al) to reach 3.0% efficiency after light soaking under forward bias. The film thickness, surface morphology, and light absorption were examined with scanning electron microscopy, optical profilometry, and UV/vis spectroscopy.

  13. Decontamination Procedure for Sorghum and Coffee Leaves Sprayed With Zinc and a Surfactant

    OpenAIRE

    Caione, Gustavo; Guirra, Ana Paula Pires Maciel; Prado, Renato de Mello; Klar, Antonio Evaldo

    2014-01-01

    Decontaminating leaf samples from crops sprayed with pesticides and nutrient solutions is important for foliar analysis. This study evaluated the effect of different washing methods in coffee and sorghum foliage that had been sprayed with zinc (with or without surfactant). The plants were sprayed with a 3 g L-1 zinc sulfate solution, with and without surfactant. Seven days later, leaves were collected and washed. The experiment was completely randomized in a 2 x 2 x 3 + 2 factorial, with thre...

  14. Modification of the solid-state nature of sulfathiazole and sulfathiazole sodium by spray drying.

    Science.gov (United States)

    Bianco, Stefano; Caron, Vincent; Tajber, Lidia; Corrigan, Owen I; Nolan, Lorraine; Hu, Yun; Healy, Anne Marie

    2012-06-01

    Solid-state characterisation of a drug following pharmaceutical processing and upon storage is fundamental to successful dosage form development. The aim of the study was to investigate the effects of using different solvents, feed concentrations and spray drier configuration on the solid-state nature of the highly polymorphic model drug, sulfathiazole (ST) and its sodium salt (STNa). The drugs were spray-dried from ethanol, acetone and mixtures of these organic solvents with water. Additionally, STNa was spray-dried from pure water. The physicochemical properties including the physical stability of the spray-dried powders were compared to the unprocessed materials. Spray drying of ST from either acetonic or ethanolic solutions with the spray drier operating in a closed cycle mode yielded crystalline powders. In contrast, the powders obtained from ethanolic solutions with the spray drier operating in an open cycle mode were amorphous. Amorphous ST crystallised to pure form I at ≤35 % relative humidity (RH) or to polymorphic mixtures at higher RH values. The usual crystal habit of form I is needle-like, but spherical particles of this polymorph were generated by spray drying. STNa solutions resulted in an amorphous material upon processing, regardless of the solvent and the spray drier configuration employed. Moisture induced crystallisation of amorphous STNa to a sesquihydrate, whilst crystallisation upon heating gave rise to a new anhydrous polymorph. This study indicated that control of processing and storage parameters can be exploited to produce drugs with a specific/desired solid-state nature.

  15. Spray Drying as a Reliable Route to Produce Metastable Carbamazepine Form IV.

    Science.gov (United States)

    Halliwell, Rebecca A; Bhardwaj, Rajni M; Brown, Cameron J; Briggs, Naomi E B; Dunn, Jaclyn; Robertson, John; Nordon, Alison; Florence, Alastair J

    2017-07-01

    Carbamazepine (CBZ) is an active pharmaceutical ingredient used in the treatment of epilepsy that can form at least 5 polymorphic forms. Metastable form IV was originally discovered from crystallization with polymer additives; however, it has not been observed from subsequent solvent-only crystallization efforts. This work reports the reproducible formation of phase pure crystalline form IV by spray drying of methanolic CBZ solution. Characterization of the material was carried out using diffraction, scanning electron microscopy, and differential scanning calorimetry. In situ Raman spectroscopy was used to monitor the spray-dried product during the spray drying process. This work demonstrates that spray drying provides a robust method for the production of form IV CBZ, and the combination of high supersaturation and rapid solid isolation from solution overcomes the apparent limitation of more traditional solution crystallization approaches to produce metastable crystalline forms. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Optimization of Pesticide Spraying Tasks via Multi-UAVs Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    He Luo

    2017-01-01

    Full Text Available Task allocation is the key factor in the spraying pesticides process using unmanned aerial vehicles (UAVs, and maximizing the effects of pesticide spraying is the goal of optimizing UAV pesticide spraying. In this study, we first introduce each UAV’s kinematic constraint and extend the Euclidean distance between fields to the Dubins path distance. We then analyze the two factors affecting the pesticide spraying effects, which are the type of pesticides and the temperature during the pesticide spraying. The time window of the pesticide spraying is dynamically generated according to the temperature and is introduced to the pesticide spraying efficacy function. Finally, according to the extensions, we propose a team orienteering problem with variable time windows and variable profits model. We propose the genetic algorithm to solve the above model and give the methods of encoding, crossover, and mutation in the algorithm. The experimental results show that this model and its solution method have clear advantages over the common manual allocation strategy and can provide the same results as those of the enumeration method in small-scale scenarios. In addition, the results also show that the algorithm parameter can affect the solution, and we provide the optimal parameters configuration for the algorithm.

  17. Leak detection systems for VVER units based on leak before break concept. PowerPoint presentation

    International Nuclear Information System (INIS)

    Matal, Oldrich

    2010-01-01

    To comply with international standards, independent leak monitoring systems should be installed based on the monitoring of different physical parameters capable of detecting any small leak within one hour from the start of the leak. Such leak detection systems are based mainly on acoustic emission monitoring, humidity monitoring and/or radiation monitoring. Advanced systems integrate the monitoring of different physical parameters into one integrated leak detection system. The Integrated Leak Detection System (ILDS) for NPP Metsamor is described. This system consists of three independent leak detection subsystems, viz. LEMOP (LEak MOnitoring of Pipelines) based on acoustic emission monitoring, HUMOS (HUmidity MOnitoring System) based on humidity monitoring, and RAMOS (RAdiation MOnitoring System) based on radiation monitoring). The Integrated Leak Detection System (ILDS) collects data from the three systems, performs data evaluation, data storage, generates alarms and provides a user interface for the whole system including all subsystems. An example of DiagAssist user interface in the ILDS system in the pictorial form. (P.A.)

  18. Staple line leak with peritonitis after laparoscopic sleeve gastrectomy - a solution in one to six steps.

    Science.gov (United States)

    Špička, Petr

    2017-06-01

    Laparoscopic sleeve gastrectomy (LSG) is one of the most efficient bariatric interventions in morbidly obese patients. The most severe risk of this procedure seems to be the staple line leak, and the management of this complication can be very arduous. To share our experience in managing the staple line leak after LSG and to help to find the best procedure that should be preferred. In the 2010-2015 period we performed 223 LSG, with about 5 demonstrating severe complications - two patients with severe bleeding requiring revision surgery, and three patients with resection surface leak. We always primarily treated the staple line leak with a laparoscopic revision. Once the fistula did not spontaneously close after this treatment. A series of other methods were then indicated for this patient and only the sixth one resulted in the desirable therapeutic success. At first, our team opted for laparoscopic revision with drainage. The next procedure involved applying Ovesco and Boston clips. As a third method we performed abscess drainage through a nasobiliary tube inserted via gastroscopy. Due to failure we performed the second laparoscopic revision with staple line resuture, the next intervention was an open revision with fistula excision and suture, and finally we opted for the application of a self-expanding metallic stent, which proved to be definitely curative. Without any guidelines it is very difficult to determine the right procedure addressing the staple line leak after LSG. It depends mainly on the clinician's experience and is lengthy and often untraditional.

  19. Formation of reflective and conductive silver film on ABS surface via covalent grafting and solution spray

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Dexin; Zhang, Yan [School of Mechanical and Automotive Engineering, South China University of Technology, 381 Wushan, Guangzhou 510640 (China); Bessho, Takeshi [Higashifuji Technical Center, Toyota Motor Corporation, 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan); Kudo, Takahiro; Sang, Jing; Hirahara, Hidetoshi; Mori, Kunio [Faculty of Engineering, Iwate University, 4-3-5 Ueda, Morioka 020-8551 (Japan); Kang, Zhixin, E-mail: zxkang@scut.edu.cn [School of Mechanical and Automotive Engineering, South China University of Technology, 381 Wushan, Guangzhou 510640 (China)

    2015-09-15

    Highlights: • A pure and homogenous silver film was deposited by spray-style plating technique. • The mechanism of covalent bonding between coating and substrate was studied. • The silver coating is highly reflective and conductive. • UV light was used to activate the ABS surface with triazine azide derivative. - Abstract: Conductive and reflective silver layers on acrylonitrile butadiene styrene (ABS) plastics have been prepared by photo grafting of triazine azides upon ultraviolet activation, self-assembling of triazine dithiols and silver electroless plating by solution spray based on silver mirror reaction. The as-prepared silver film exhibited excellent adhesion with ABS owing to covalent bonds between coating and substrate, and the detailed bonding mechanism have been investigated by X-ray photoelectron spectroscopy (XPS). X-ray diffraction (XRD) result revealed that silver film on ABS was pure and with a nanocrystalline structure. Atomic force microscope (AFM) analysis demonstrated that massive silver particles with sizes varying from 80 to 120 nm were deposited on ABS and formed a homogenous and smooth coating, resulting in highly reflective surface. Furthermore, silver maintained its unique conductivity even as film on ABS surface in term of four-point probe method.

  20. Formation of reflective and conductive silver film on ABS surface via covalent grafting and solution spray

    International Nuclear Information System (INIS)

    Chen, Dexin; Zhang, Yan; Bessho, Takeshi; Kudo, Takahiro; Sang, Jing; Hirahara, Hidetoshi; Mori, Kunio; Kang, Zhixin

    2015-01-01

    Highlights: • A pure and homogenous silver film was deposited by spray-style plating technique. • The mechanism of covalent bonding between coating and substrate was studied. • The silver coating is highly reflective and conductive. • UV light was used to activate the ABS surface with triazine azide derivative. - Abstract: Conductive and reflective silver layers on acrylonitrile butadiene styrene (ABS) plastics have been prepared by photo grafting of triazine azides upon ultraviolet activation, self-assembling of triazine dithiols and silver electroless plating by solution spray based on silver mirror reaction. The as-prepared silver film exhibited excellent adhesion with ABS owing to covalent bonds between coating and substrate, and the detailed bonding mechanism have been investigated by X-ray photoelectron spectroscopy (XPS). X-ray diffraction (XRD) result revealed that silver film on ABS was pure and with a nanocrystalline structure. Atomic force microscope (AFM) analysis demonstrated that massive silver particles with sizes varying from 80 to 120 nm were deposited on ABS and formed a homogenous and smooth coating, resulting in highly reflective surface. Furthermore, silver maintained its unique conductivity even as film on ABS surface in term of four-point probe method

  1. Simple and double microencapsulation of Lactobacillus acidophilus with chitosan using spray drying

    Directory of Open Access Journals (Sweden)

    Isela A. Flores-Belmont

    2015-10-01

    Full Text Available The aim of this study was to evaluate the survival of Lactobacillus acidophilus that had been simple or double spray dried using chitosan to cause microencapsulation and which had been exposed to model gastrointestinal conditions. In addition, the study also determined the physicochemical properties of the powder containing the microencapsulated probiotic.Chitosan-inulin or chitosan-maltodextrin (1:15 or 1:25 solutions were inoculated with 1012 cfu mL-1 of L. acidophilus, for simple microencapsulation. The different solutions were dried using a spray dryer with an inlet air temperature of 130°C and a solution flux of 4.8 g min-1. A two-step process was used for the double microencapsulation. In the first step, the probiotic was added to a gelatin-maltodextrin (1:25 solution and then spray dried; for the second step, the microencapsulated probiotic was added to a chitosan-inulin or chitosan-maltodextrin (1:25 solution and then it was spray dried again.With the simple microencapsulated probiotic, a microbial reduction of 7 log cycles was obtained. With the double microencapsulated probiotic only 3 log reductions were achieved. The double microencapsulated probiotic thus demonstrated greater resistance to simulated gastrointestinal conditions. The powders produced were shown to have water activity values of 0.176 - 0.261 at 25 °C and moisture content of 0.8 – 1.0%, which are characteristic of spray dried products. The bulk density was significantly (p < 0.05 lower (300 kg m-3 for simple than for double (400 kg m-3 microencapsulated probiotic powders. Solubility and dispersibility of the powder microcapsules were better at lower pH values.Double microencapsulation using a process of spray drying is therefore recommended for probiotics, thus exploiting chitosan’s insolubility in water, which can be applied for the of development food products.

  2. Use of cheese whey for biomass production and spray drying of probiotic lactobacilli.

    Science.gov (United States)

    Lavari, Luisina; Páez, Roxana; Cuatrin, Alejandra; Reinheimer, Jorge; Vinderola, Gabriel

    2014-08-01

    The double use of cheese whey (culture medium and thermoprotectant for spray drying of lactobacilli) was explored in this study for adding value to this wastewater. In-house formulated broth (similar to MRS) and dairy media (cheese and ricotta whey and whey permeate) were assessed for their capacity to produce biomass of Lactobacillus paracasei JP1, Lb. rhamnosus 64 and Lb. gasseri 37. Simultaneously, spray drying of cheese whey-starch solution (without lactobacilli cells) was optimised using surface response methodology. Cell suspensions of the lactobacilli, produced in in house-formulated broth, were spray-dried in cheese whey-starch solution and viability monitored throughout the storage of powders for 2 months. Lb. rhamnosus 64 was able to grow satisfactorily in at least two of the in-house formulated culture media and in the dairy media assessed. It also performed well in spray drying. The performance of the other strains was less satisfactory. The growth capacity, the resistance to spray drying in cheese whey-starch solution and the negligible lost in viability during the storage (2 months), makes Lb. rhamnosus 64 a promising candidate for further technological studies for developing a probiotic dehydrated culture for foods, utilising wastewaters of the dairy industry (as growth substrate and protectant) and spray drying (a low-cost widely-available technology).

  3. Leak Signature Space: An Original Representation for Robust Leak Location in Water Distribution Networks

    Directory of Open Access Journals (Sweden)

    Myrna V. Casillas

    2015-03-01

    Full Text Available In this paper, an original model-based scheme for leak location using pressure sensors in water distribution networks is introduced. The proposed approach is based on a new representation called the Leak Signature Space (LSS that associates a specific signature to each leak location being minimally affected by leak magnitude. The LSS considers a linear model approximation of the relation between pressure residuals and leaks that is projected onto a selected hyperplane. This new approach allows to infer the location of a given leak by comparing the position of its signature with other leak signatures. Moreover, two ways of improving the method’s robustness are proposed. First, by associating a domain of influence to each signature and second, through a time horizon analysis. The efficiency of the method is highlighted by means of a real network using several scenarios involving different number of sensors and considering the presence of noise in the measurements.

  4. EPLD/CPLD based solution for sodium vapour leak detection processing instrumentation - ECIL's development, design, manufacturing and commissioning for implementation of DDCS at SGTF, IGCAR

    International Nuclear Information System (INIS)

    Rajasekhara Rao, K.S.; Mitra, S.G.; Kannaiah, B.

    2004-01-01

    For the Complex Process and Instrumentation needs of Sodium System of SGTF (Steam Generator Test Facility) of IGCAR, ECIL has developed the State of the Art EPLD / CPLD based solutions for Sodium Vapour Leak Detection Processing with Distributed I/O Intelligence for the task of Acquiring the Data, Analog to Digital Conversion, Data Interpretation as Sodium Leak, Healthy, Sensor /Cable Open/Short, Annunciation and Data Communication with DDCS. The System is flexible on a programmable chip for each group of 32 Sensors Data Processing and the Processing is Software Controlled rather than traditional hardware based. The System is adaptable to process requirement changes with simple Software updation/tuning rather than cumbersome and time-consuming hardware changes. Since the design is Software based, there is no drift and it is calibration free. The implementation is based on conceptual Design, Schematic Capture, VHDL Coding and Compilation, EPLD/CPLD Programming using J-Tag, Prefabrication Simulation Testing with Test Bench, Thermal-EMI-EMC Analysis, Fabrication, Assembly and Testing. The Leak Detection Processing is Integrated as part of 'DDCS - Developed, Designed, Manufactured and Commissioned at SGTF, IGCAR' consisting of Dual Redundant Multi Loop PID Controllers/PLCs, DAS and net worked HMI. The System is well established and, operational at IGCAR. (author)

  5. Routine intraoperative leak testing for sleeve gastrectomy: is the leak test full of hot air?

    Science.gov (United States)

    Bingham, Jason; Lallemand, Michael; Barron, Morgan; Kuckelman, John; Carter, Preston; Blair, Kelly; Martin, Matthew

    2016-05-01

    Staple line leak after sleeve gastrectomy (SG) is a rare but dreaded complication with a reported incidence of 0% to 8%. Many surgeons routinely test the staple line with an intraoperative leak test (IOLT), but there is little evidence to validate this practice. In fact, there is a theoretical concern that the leak test may weaken the staple line and increase the risk of a postop leak. Retrospective review of all SGs performed over a 7-year period was conducted. Cases were grouped by whether an IOLT was performed, and compared for the incidence of postop staple line leaks. The ability of the IOLT for identifying a staple line defect and for predicting a postoperative leak was analyzed. Five hundred forty-two SGs were performed between 2007 and 2014. Thirteen patients (2.4%) developed a postop staple line leak. The majority of patients (n = 494, 91%) received an IOLT, including all 13 patients (100%) who developed a subsequent clinical leak. There were no (0%) positive IOLTs and no additional interventions were performed based on the IOLT. The IOLT sensitivity and positive predictive value were both 0%. There was a trend, although not significant, to increase leak rates when a routine IOLT was performed vs no routine IOLT (2.6% vs 0%, P = .6). The performance of routine IOLT after SG provided no actionable information, and was negative in all patients who developed a postoperative leak. The routine use of an IOLT did not reduce the incidence of postop leak, and in fact was associated with a higher leak rate after SG. Published by Elsevier Inc.

  6. Nanoparticles by spray drying using innovative new technology: the Büchi nano spray dryer B-90.

    Science.gov (United States)

    Li, Xiang; Anton, Nicolas; Arpagaus, Cordin; Belleteix, Fabrice; Vandamme, Thierry F

    2010-10-15

    Spray drying technology is widely known and used to transform liquids (solutions, emulsions, suspension, slurries, pastes or even melts) into solid powders. Its main applications are found in the food, chemical and materials industries to enhance ingredient conservation, particle properties, powder handling and storage etc. However, spray drying can also be used for specific applications in the formulation of pharmaceuticals for drug delivery (e.g. particles for pulmonary delivery). Büchi is a reference in the development of spray drying technology, notably for laboratory scale devices. This study presents the Nano Spray Dryer B-90, a revolutionary new sprayer developed by Büchi, use of which can lower the size of the produced dried particles by an order of magnitude attaining submicron sizes. In this paper, results are presented with a panel of five representative polymeric wall materials (arabic gum, whey protein, polyvinyl alcohol, modified starch, and maltodextrin) and the potentials to encapsulate nano-emulsions, or to formulate nano-crystals (e.g. from furosemide) are also shown. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Reactor Containment Spray Technology Program

    Energy Technology Data Exchange (ETDEWEB)

    Row, T. H. [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1968-12-15

    The design basis accident in water moderated power reactors is a loss-of-coolant accident in which water sprays are generally employed to control the containment pressure transient by condensing the released steam-air mixture. Additives to the spray have been proposed as a way to increase their usefulness by enhancing the removal of various forms of radioiodine from the containment atmosphere. A program to investigate the gas-liquid systems involved is co-ordinated by ORNL for the US Atomic Energy Commission. A basic part of the program is the search for various chemical additives that will increase the spray affinity for molecular iodine and methyl iodide. A method for evaluating additives was developed that measures equilibrium distribution coefficients for iodine between air and aqueous solutions. Additives selected are used in single drop-wind tunnel experiments where the circulating gas contains iodine or CH{sub 3}I. Mass transfer coefficients and transient distribution coefficients have been determined as a function of relative humidity, temperature, drop size, and solution pH and concentration. Tests have shown that surfactants and organic amines increase the solution ability to getter CH{sub 3}l. Results from single drop tests help in planning spray experiments in the Nuclear Safety Pilot Plant, a large ({approx}38 m{sup 3}) facility, where accident conditions are closely simulated. Iodine and CH{sub 3}I removal rates have been determined for a number of solutions, including 1 wt% Na{sub 2}S{sub 2}O{sub 3} + 3000 ppm B + 0.153 M NaOH and 3000 ppm B + 0.153 M NaOH. The additive has very little effect in removal of I{sub 2} with half-lives of less than 1 mm typical for any aqueous solution. These same solutions remove CH{sub 3}I with a half-life of one hour. Analytical models for the removal processes have been developed. Consideration is also being given to corrosion, thermal and radiation stability of the solutions. Radiation studies have indicated the loss

  8. Deconstructing Gender Stereotypes in Leak

    Directory of Open Access Journals (Sweden)

    Nengah Bawa Atmadja

    2015-05-01

    Full Text Available The belief of Balinese people towards leak still survive. Leak is a magic based on durgaism that can transform a person from human to another form, such as apes, pigs, etc. People tend to regard leak as evil. In general, the evilness is constructed in gender stereotypes, so it is identified that leak are always women. This idea is a power game based on the ideology of patriarchy that provides legitimacy for men to dominate women with a plea for social harmony. As a result, women are marginalized in the Balinese society. Women should be aware of so it would provide encouragement for them to make emancipatory changes dialogically. Kepercayaan orang Bali terhadap leak tetap bertahan sampai saat ini. Leak adalah sihir yang berbasiskan durgaisme yang dapat mengakibatkan seseorang bisa merubah bentuk dari manusia ke wujud yang lain, misalnya kera, babi, dll. Leak termasuk magi hitam sehingga dinilai bersifat jelek. Pada umumnya perempuan diidentikkan dengan leak sehingga melahirkan asumsi yang bermuatan steriotip gender bahwa leak = perempuan. Gagasan ini merupakan permainan kekuasaan berbasis ideologi patriarkhi dan sekaligus memberikan legitimasi bagi laki-laki untuk menguasai perempuan dengan dalih demi keharmonisan sosial. Akibatnya, perempuan menjadi termarginalisasi pada masyarakat Bali.  Perempuan harus menyadarinya sehingga memberikan dorongan bagi mereka untuk melakukan perubahan secara dialogis emansipatoris.

  9. Sea Spray Aerosols

    DEFF Research Database (Denmark)

    Butcher, Andrew Charles

    emissions produced directly from bubble bursting as the result of air entrainment from breaking waves and particles generated from secondary emissions of volatile organic compounds. In the first paper, we study the chemical properties of particles produced from several sea water proxies with the use...... of a cloud condensation nuclei ounter. Proxy solutions with high inorganic salt concentrations and some organics produce sea spray aerosol particles with little change in cloud condensation activity relative to pure salts. Comparison is made between a frit based method for bubble production and a plunging...... a relationship between plunging jet particle ux, oceanic particle ux, and energy dissipation rate in both systems. Previous sea spray aerosol studies dissipate an order of magnitude more energy for the same particle ux production as the open ocean. A scaling factor related to the energy expended in air...

  10. Hermetic compartments leak-tightness enhancement

    International Nuclear Information System (INIS)

    Murani, J.

    2000-01-01

    In connection with the enhancement of the nuclear safety of the Jaslovske Bohunice V-1 NPP actions for the increase of the leak tightness are performed. The reconstruction has been done in the following directions: hermetic compartments leak tightness enhancement; air lock installation; installation of air lock in SP 4 vent system; integrated leakage rate test to hermetic compartments with leak detection. After 'major' leaks on the hermetic boundary components had been eliminated, since 1994 works on a higher qualitative level began. The essence of the works consists in the detection and identification of leaks in the structural component of the hermetic boundary during the planned refueling outages. The results of the Small Reconstruction and gradual enhancement of leak tightness are presented

  11. Fundamental Study on the Effect of Spray Parameters on Characteristics of P3HT:PCBM Active Layers Made by Spray Coating

    Directory of Open Access Journals (Sweden)

    Yu Xie

    2015-08-01

    Full Text Available This paper is an attempt to elucidate the effects of the important spray characteristics on the surface morphology and light absorbance of spray-on P3HT:PCBM thin-films, used as an active layer in polymer solar cells (PSCs. Spray coating or deposition is a viable scalable technique for the large-scale, fast, and low-cost fabrication of solution-processed solar cells, and has been widely used for device fabrication, although the fundamental understanding of the underlying and controlling parameters, such as spray characteristics, droplet dynamics, and surface wettability, is still limited, making the results on device fabrication not reproducible and unreliable. In this paper, following the conventional PSC architecture, a PEDOT:PSS layer is first spin-coated on glass substrates, followed by the deposition of P3HT:PCBM using an automatic ultrasonic spray coating system, with a movable nozzle tip, to mimic an industrial manufacturing process. To gain insight, the effects of the spray carrier air pressure, the number of spray passes, the precursor flow rate, and precursor concentration are studied on the surface topography and light absorbance spectra of the spray-on films. Among the results, it is found that despite the high roughness of spray-on films, the light absorbance of the film is satisfactory. It is also found that the absorbance of spray-on films is a linear function of the number of spray passes or deposition layers, based on which an effective film thickness is defined for rough spray-on films. The effective thickness of a rough spray-on P3HT:PCBM film was found to be one-quarter of that of a flat film predicted by a simple mass balance.

  12. 40 CFR 63.1024 - Leak repair.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Leak repair. 63.1024 Section 63.1024... Standards for Equipment Leaks-Control Level 2 Standards § 63.1024 Leak repair. (a) Leak repair schedule. The owner or operator shall repair each leak detected as soon as practical, but not later than 15 calendar...

  13. Vehicle-based Methane Mapping Helps Find Natural Gas Leaks and Prioritize Leak Repairs

    Science.gov (United States)

    von Fischer, J. C.; Weller, Z.; Roscioli, J. R.; Lamb, B. K.; Ferrara, T.

    2017-12-01

    Recently, mobile methane sensing platforms have been developed to detect and locate natural gas (NG) leaks in urban distribution systems and to estimate their size. Although this technology has already been used in targeted deployment for prioritization of NG pipeline infrastructure repair and replacement, one open question regarding this technology is how effective the resulting data are for prioritizing infrastructure repair and replacement. To answer this question we explore the accuracy and precision of the natural gas leak location and emission estimates provided by methane sensors placed on Google Street View (GSV) vehicles. We find that the vast majority (75%) of methane emitting sources detected by these mobile platforms are NG leaks and that the location estimates are effective at identifying the general location of leaks. We also show that the emission rate estimates from mobile detection platforms are able to effectively rank NG leaks for prioritizing leak repair. Our findings establish that mobile sensing platforms are an efficient and effective tool for improving the safety and reducing the environmental impacts of low-pressure NG distribution systems by reducing atmospheric methane emissions.

  14. 40 CFR 63.1005 - Leak repair.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Leak repair. 63.1005 Section 63.1005... Standards for Equipment Leaks-Control Level 1 § 63.1005 Leak repair. (a) Leak repair schedule. The owner or operator shall repair each leak detected no later than 15 calendar days after it is detected, except as...

  15. 40 CFR 65.105 - Leak repair.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Leak repair. 65.105 Section 65.105... FEDERAL AIR RULE Equipment Leaks § 65.105 Leak repair. (a) Leak repair schedule. The owner or operator shall repair each leak detected as soon as practical but not later than 15 calendar days after it is...

  16. Analyzing User Awareness of Privacy Data Leak in Mobile Applications

    Directory of Open Access Journals (Sweden)

    Youngho Kim

    2015-01-01

    Full Text Available To overcome the resource and computing power limitation of mobile devices in Internet of Things (IoT era, a cloud computing provides an effective platform without human intervention to build a resource-oriented security solution. However, existing malware detection methods are constrained by a vague situation of information leaks. The main goal of this paper is to measure a degree of hiding intention for the mobile application (app to keep its leaking activity invisible to the user. For real-world application test, we target Android applications, which unleash user privacy data. With the TaintDroid-ported emulator, we make experiments about the timing distance between user events and privacy leaks. Our experiments with Android apps downloaded from the Google Play show that most of leak cases are driven by user explicit events or implicit user involvement which make the user aware of the leakage. Those findings can assist a malware detection system in reducing the rate of false positive by considering malicious intentions. From the experiment, we understand better about app’s internal operations as well. As a case study, we also presents a cloud-based dynamic analysis framework to perform a traffic monitor.

  17. PFR evaporator leak

    International Nuclear Information System (INIS)

    Smedley, J.A.

    1975-01-01

    PFR has three heat removal circuits each one having an evaporator, superheater, reheater; all separate units. The status of the system was that circuit No 3 was steaming with 10 MW thermal nuclear power; No 1 circuit was filled with sodium but with the evaporator awaiting modification to cure gas entrainment problems already reported. The leak was in No 2 circuit and was located in the evaporator unit. The evaporator is rated at 120 M thermal at full power and as such is a large unit. The circuit was filled with both sodium and water for the first time three weeks before the conference so it was recent history being reported and therefore any figures quoted should be taken as indicative only. The history of the steam generator was that it was built at works to a very high standard and underwent all the usual tests of strength, inspection of welds and helium leak testing. The steam generator is of U tube design with a tube plate to which the boiler tubes are welded, with all the welds in one of two gas spaces. The inlet and outlet sides are separated by a baffle and the salient features are illustrated in the attached figure. The unit achieved a leak tightness better than the detection limit in the helium leak test at works. This limit was assessed as being less than an equivalent leak of 10 -6 g/s water under steam generator service conditions. However even though all the steam generator units passed this test at works a further test was carried out when the circuits had been completed. The test was carried out during commissioning after sodium filling and with the units hot. The method was to introduce a mixture of helium/ argon at 500 pounds/square inch into the water side of the steam generators and measure the helium concentration in the sodium side gas spaces of the circuit. The test lasted many days and under these conditions the sensitivity is such that a leak equivalent to somewhere between 10 -7 to 10 -6 g/s equivalent water leak could be detected, i

  18. PFR evaporator leak

    Energy Technology Data Exchange (ETDEWEB)

    Smedley, J A

    1975-07-01

    PFR has three heat removal circuits each one having an evaporator, superheater, reheater; all separate units. The status of the system was that circuit No 3 was steaming with 10 MW thermal nuclear power; No 1 circuit was filled with sodium but with the evaporator awaiting modification to cure gas entrainment problems already reported. The leak was in No 2 circuit and was located in the evaporator unit. The evaporator is rated at 120 M thermal at full power and as such is a large unit. The circuit was filled with both sodium and water for the first time three weeks before the conference so it was recent history being reported and therefore any figures quoted should be taken as indicative only. The history of the steam generator was that it was built at works to a very high standard and underwent all the usual tests of strength, inspection of welds and helium leak testing. The steam generator is of U tube design with a tube plate to which the boiler tubes are welded, with all the welds in one of two gas spaces. The inlet and outlet sides are separated by a baffle and the salient features are illustrated in the attached figure. The unit achieved a leak tightness better than the detection limit in the helium leak test at works. This limit was assessed as being less than an equivalent leak of 10{sup -6} g/s water under steam generator service conditions. However even though all the steam generator units passed this test at works a further test was carried out when the circuits had been completed. The test was carried out during commissioning after sodium filling and with the units hot. The method was to introduce a mixture of helium/ argon at 500 pounds/square inch into the water side of the steam generators and measure the helium concentration in the sodium side gas spaces of the circuit. The test lasted many days and under these conditions the sensitivity is such that a leak equivalent to somewhere between 10{sup -7} to 10{sup -6} g/s equivalent water leak could be

  19. Comparison of leak opening and leak rate calculations to HDR experimental results

    International Nuclear Information System (INIS)

    Grebner, H.; Hoefler, A.; Hunger, H.

    1993-01-01

    During the last years a number of calculations of leak opening and leak rate for through cracks in piping components have been performed. Analyses are pre- or mostly post-calculations to experiments performed at the HDR facility under PWR operating conditions. Piping components under consideration were small diameter straight pipes with circumferential cracks, pipe bends with longitudinal or circumferential cracks and pipe branches with weldment cracks. The components were loaded by internal pressure and opening as well as closing bending moment. The finite element method and two-phase flow leak rate programs were used for the calculations. Results of the analyses are presented as J-integral values, crack opening displacements and areas and leak rates as well as comparisons to the experimental results

  20. Low-cost plasmonic solar cells prepared by chemical spray pyrolysis

    Directory of Open Access Journals (Sweden)

    Erki Kärber

    2014-12-01

    Full Text Available Solar cells consisting of an extremely thin In2S3/CuInS2 buffer/absorber layer uniformly covering planar ZnO were prepared entirely by chemical spray pyrolysis. Au nanoparticles (Au-NPs were formed via thermal decomposition of a gold(III chloride trihydrate (HAuCl4·3H2O precursor by spraying 2 mmol/L of the aqueous precursor solution onto a substrate held at 260 °C. Current–voltage scans and external quantum efficiency spectra were used to evaluate the solar cell performance. This work investigates the effect of the location of the Au-NP layer deposition (front side vs rear side in the solar cell and the effect of varying the volume (2.5–10 mL of the sprayed Au precursor solution. A 63% increase (from 4.6 to 7.5 mA/cm2 of the short-circuit current density was observed when 2.5 mL of the precursor solution was deposited onto the rear side of the solar cell.

  1. 29 CFR 1910.163 - Fixed extinguishing systems, water spray and foam.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Fixed extinguishing systems, water spray and foam. 1910.163... Suppression Equipment § 1910.163 Fixed extinguishing systems, water spray and foam. (a) Scope and application. This section applies to all fixed extinguishing systems, using water or foam solution as the...

  2. Physico-chemical aspects of radionuclide removal under accident conditions in nuclear power plants by means of containment-building spray systems

    International Nuclear Information System (INIS)

    Alm, M.

    1976-01-01

    A survey is given on industrial spray solutions, their thermal and radiation stability, drop effects, and the corrosion behaviour of reactor and containment materials. From the hitherto known spray experiments it may be concluded that (1) spray solutions can be used for the effective decontamination of the containment atmosphere in the event of a loss-of-coolant accident, (2) the spray efficiency for the removal of gaseous and volatile fission products can be assessed by means of simplified model considerations, (3) further work is necessary to optimize the technology of the spray process. (author)

  3. The Influence of Ammonium Sulphate added to the Spray Solution of Calcium Carbonate-Containing Glyphosate and Nicosulfuron on Barnyardgrass and Velvetleaf Control

    Directory of Open Access Journals (Sweden)

    kamal hajmohamadnia

    2016-09-01

    the above, basic experiments carried out as the influence of adding ammonium sulphate to spray solution of calcium carbonate-containing glyphosate and nicosulfuron on barnyardgrass and velvetleaf control. Materials and Methods: Four experiments were performed as factorial arrangement of treatments 6×2 based on completely randomized design with six replications (+six control pots for each weed species at Research Greenhouse of the Ferdowsi University of Mashhad in 2010. Factors were included different concentrations of calcium carbonate (CaCO3; Merck, Germany of water in spray tank at six levels 0, 100, 200, 300, 400 and 500 ppm in deionized water (w/v in combination with 0 (-AMS or 3 kg/ha (+AMS ammonium sulphate (Merck, Germany as adjuster the hardness. Glyphosate (Roundup® and nicosulfuron (Cruse® herbicides were applied post emergent at 385 and 550 mL ha-1 as commercial products (158 and 22 g ai ha-1; based on ED50 outcome preliminary test (12, recpectively at the 3-4 leaf stage of the weeds (barnyardgrass and velvetleaf in a spray volume of 250 L ha-1. Four weeks after treatment, survival, plant height, leaf area, and shoot dry weight of weeds (% control were calculated. The data of experiment were subjected to ANOVA using MSTATC software. Means of the treatments were separated using Duncan’s Multiple Range Test at α = 0.05. Also, based on the distribution of data, regression analysis was used as linear, two, and third-degree polynomial by EXCEL 2007. Results and Discussion: The results showed a significant reduction (p≤0.01 for survival, plant height, leaf area, and shoot dry weight of weeds (% control with addition of calcium carbonate in spray tank of glyphosate and nicosulfuron herbicides, but this effect was not similar. So that, 500 ppm Ca2+ to the nicosulfuron spray solution compared with its absence increased barnyardgrass and velvetleaf biomass (% control 16 and 50%, respectively. The corresponding values for glyphosate were 78 and 51

  4. Intraoperative air leak measured after lobectomy is associated with postoperative duration of air leak.

    Science.gov (United States)

    Brunelli, Alessandro; Salati, Michele; Pompili, Cecilia; Gentili, Paolo; Sabbatini, Armando

    2017-11-01

    To verify the association between the air leak objectively measured intraoperatively (IAL) using the ventilator and the air leak duration after pulmonary lobectomy. Prospective analysis on 111 patients submitted to pulmonary lobectomy (33 by video-assisted thoracic surgery). After resection, objective assessment of air leak (in milliliter per minute) was performed before closure of the chest by measuring the difference between a fixed inspired and expired volume, using a tidal volume of 8 ml/kg, a respiratory rate of 10 and a positive-end expiratory pressure of 5 cmH2O. A multivariable analysis was performed for identifying factors associated with duration of postoperative air leak. Average IAL was 158 ml/min (range 0-1500 ml/min). The best cut-off (receiver-operating characteristics analysis) associated with air leak longer than 5 days was 500 ml/min. Nine patients had IAL >500 ml/min (8%). They had a longer duration of postoperative air leak compared with those with a lower IAL (mean values, 10.1 days, SD 8.8 vs 1.5 days, SD 4.9 P leak duration after multivariable regression: left side resection (P = 0.018), upper site resection (P = 0.031) and IAL >500 ml/min (P leak duration was generated: 1.7 + 2.4 × left side + 2.2 × upper site + 8.8 × IAL >500. The air leak measurement using the ventilator parameters after lung resection may assist in estimating the risk of postoperative prolonged air leak. An IAL > 500 ml/min may warrant the use of intraoperative preventative measures, particularly after video-assisted thoracic surgery lobectomy where a submersion test is often unreliable. © 2017 European Society of Cardiology and European Atherosclerosis Association. All rights reserved. For permissions please email: journals.permissions@oup.com.

  5. Preliminary study of the use of radiotracers for leak detection in industrial applications

    International Nuclear Information System (INIS)

    Wetchagarun, S; Petchrak, A; Tippayakul, C

    2015-01-01

    One of the most widespread uses of radiotracers in the industrial applications is the leak detection of the systems. This technique can be applied, for example, to detect leak in heat exchangers or along buried industrial pipelines. The ability to perform online investigation is one of the most important advantages of the radiotracer technique over other non-radioactive leak detection methods. In this paper, a preliminary study of the leak detection using radiotracer in the laboratory scale was presented. Br-82 was selected for this work due to its chemical property, its suitable half-life and its on-site availability. The NH 4 Br in the form of aqueous solution was injected into the experimental system as the radiotracer. Three NaI detectors were placed along the pipelines to measure system flow rate and to detect the leakage from the piping system. The results obtained from the radiotracer technique were compared to those measured by other methods. It is found that the flow rate obtained from the radiotracer technique agreed well with the one obtained from the flow meter. The leak rate result, however, showed discrepancy between results obtained from two different measuring methods indicating further study on leak detection was required before applying this technique in the industrial system. (paper)

  6. Preliminary study of the use of radiotracers for leak detection in industrial applications

    Science.gov (United States)

    Wetchagarun, S.; Petchrak, A.; Tippayakul, C.

    2015-05-01

    One of the most widespread uses of radiotracers in the industrial applications is the leak detection of the systems. This technique can be applied, for example, to detect leak in heat exchangers or along buried industrial pipelines. The ability to perform online investigation is one of the most important advantages of the radiotracer technique over other non-radioactive leak detection methods. In this paper, a preliminary study of the leak detection using radiotracer in the laboratory scale was presented. Br-82 was selected for this work due to its chemical property, its suitable half-life and its on-site availability. The NH4Br in the form of aqueous solution was injected into the experimental system as the radiotracer. Three NaI detectors were placed along the pipelines to measure system flow rate and to detect the leakage from the piping system. The results obtained from the radiotracer technique were compared to those measured by other methods. It is found that the flow rate obtained from the radiotracer technique agreed well with the one obtained from the flow meter. The leak rate result, however, showed discrepancy between results obtained from two different measuring methods indicating further study on leak detection was required before applying this technique in the industrial system.

  7. Conformational basis for the Li(+)-induced leak current in the rat gamma-aminobutyric acid (GABA) transporter-1

    DEFF Research Database (Denmark)

    MacAulay, Nanna; Zeuthen, Thomas; Gether, Ulrik

    2002-01-01

    The rat gamma-aminobutyric acid transporter-1 (GAT-1) was expressed in Xenopus laevis oocytes and the substrate-independent Li(+)-induced leak current was examined using two-electrode voltage clamp. The leak current was not affected by the addition of GABA and was not due to H(+) permeation. The Li......(+)-bound conformation of the protein displayed a lower passive water permeability than that of the Na(+)- and choline (Ch(+))-bound conformations and the leak current did not saturate with increasing amounts of Li(+) in the test solution. The mechanism that gives rise to the leak current did not support active water...... transport in contrast to the mechanism responsible for GABA translocation (approximately 330 water molecules per charge). Altogether, these data support the distinct nature of the leak conductance in relation to the substrate translocation process. It was observed that the leak current was inhibited by low...

  8. Effect of precursor concentration and spray pyrolysis temperature upon hydroxyapatite particle size and density.

    Science.gov (United States)

    Cho, Jung Sang; Lee, Jeong-Cheol; Rhee, Sang-Hoon

    2016-02-01

    In the synthesis of hydroxyapatite powders by spray pyrolysis, control of the particle size was investigated by varying the initial concentration of the precursor solution and the pyrolysis temperature. Calcium phosphate solutions (Ca/P ratio of 1.67) with a range of concentrations from 0.1 to 2.0 mol/L were prepared by dissolving calcium nitrate tetrahydrate and diammonium hydrogen phosphate in deionized water and subsequently adding nitric acid. Hydroxyapatite powders were then synthesized by spray pyrolysis at 900°C and at 1500°C, using these calcium phosphate precursor solutions, under the fixed carrier gas flow rate of 10 L/min. The particle size decreased as the precursor concentration decreased and the spray pyrolysis temperature increased. Sinterability tests conducted at 1100°C for 1 h showed that the smaller and denser the particles were, the higher the relative densities were of sintered hydroxyapatite disks formed from these particles. The practical implication of these results is that highly sinterable small and dense hydroxyapatite particles can be synthesized by means of spray pyrolysis using a low-concentration precursor solution and a high pyrolysis temperature under a fixed carrier gas flow rate. © 2015 Wiley Periodicals, Inc.

  9. SPRAY CASTING

    OpenAIRE

    SALAMCI, Elmas

    2010-01-01

    ABSTRACT This paper is designed to provide a basic review of spray casting. A brief overview of the historical development of spray  casting and the description of plant and equipment have been given. Following metallurgical characteristics of spray formed alloys, process parameters and solidification mechanism of spray deposition have been discussed in detail. Finally, microstructure and mechanical properties of the selected spray cast Al-Zn-Mg-Cu alloys have been presented and comp...

  10. Bactericidal Effects of HVOF-Sprayed Nanostructured TiO2 on Pseudomonas aeruginosa

    Science.gov (United States)

    Jeffery, B.; Peppler, M.; Lima, R. S.; McDonald, A.

    2010-01-01

    Titanium dioxide (TiO2) has been shown to exhibit photocatalytic bactericidal activity. This preliminary study focused on examining the photocatalytic activity of high-velocity oxy-fuel (HVOF) sprayed nanostructured TiO2 coatings to kill Pseudomonas aeruginosa. The surfaces of the nanostructured TiO2 coatings were lightly polished before addition of the bacterial solution. Plates of P. aeruginosa were grown, and then suspended in a phosphate buffer saline (PBS) solution. The concentration of bacteria used was determined by a photo-spectrometer, which measured the amount of light absorbed by the bacteria-filled solution. This solution was diluted and pipetted onto the coating, which was exposed to white light in 30-min intervals, up to 120 min. It was found that on polished HVOF-sprayed coatings exposed to white light, 24% of the bacteria were killed after exposure for 120 min. On stainless steel controls, approximately 6% of the bacteria were not recovered. These preliminary results show that thermal-sprayed nanostructured TiO2 coatings exhibited photocatalytic bactericidal activity with P. aeruginosa.

  11. Modeling of Spray System Operation under Hydrogen and Steam Emissions in NPP Containment during Severe Accident

    Directory of Open Access Journals (Sweden)

    Vadim E. Seleznev

    2011-01-01

    Full Text Available The paper describes one of the variants of mathematical models of a fluid dynamics process inside the containment, which occurs in the conditions of operation of spray systems in severe accidents at nuclear power plant. The source of emergency emissions in this case is the leak of the coolant or rupture at full cross-section of the main circulating pipeline in a reactor building. Leak or rupture characteristics define the localization and the temporal law of functioning of a source of emergency emission (or accrued operating of warmed up hydrogen and steam in the containment. Operation of this source at the course of analyzed accident models should be described by the assignment of the relevant Dirichlet boundary conditions. Functioning of the passive autocatalytic recombiners of hydrogen is described in the form of the complex Newton boundary conditions.

  12. Taxonomy of Strategic Games with Information Leaks and Corruption of Simultaneity

    Directory of Open Access Journals (Sweden)

    Valeriu Ungureanu

    2016-04-01

    Full Text Available We consider pseudo-simultaneous normal form games - strategic games with rules violated by information leaks and simultaneity corruption. We provide classification and construction of a game taxonomy based on applicable solution principles. Existence conditions are highlighted, formulated and analysed.

  13. Plasma sprayed coatings on crankshaft used steels

    Science.gov (United States)

    Mahu, G.; Munteanu, C.; Istrate, B.; Benchea, M.

    2017-08-01

    Plasma spray coatings may be an alternative to conventional heat treatment of main journals and crankpins of the crankshaft. The applications of plasma coatings are various and present multiple advantages compared to electric arc wire spraying or flame spraying. The study examines the layers sprayed with the following powders: Cr3C2- 25(Ni 20Cr), Al2O3- 13TiO2, Cr2O3-SiO2- TiO2 on the surface of steels used in the construction of a crankshaft (C45). The plasma spray coatings were made with the Spray wizard 9MCE facility at atmospheric pressure. The samples were analyzed in terms of micro and morphological using optical microscopy, scanning electron microscopy and X-ray diffraction. Wear tests on samples that have undergone simulates extreme working conditions of the crankshafts. In order to emphasize adherence to the base material sprayed layer, were carried out tests of microscratches and micro-indentation. Results have showed a relatively compact morphological aspect given by the successive coatings with splat-like specific structures. Following the microscratch analysis it can be concluded that Al2O3-13TiO2 coating has a higher purpose in terms of hardness compared to Cr3C2-(Ni 20Cr) and Cr2O3-SiO2- TiO2 powders. Thermal coatings of the deposited powders have increased the mechanical properties of the material. The results stand to confirm that plasma sprayed Al2O3-13TiO2 powder is in fact a efficient solution for preventing mechanical wear, even with a faulty lubrication system.

  14. Permanent underwater leak detector

    International Nuclear Information System (INIS)

    Costello, L; McStay, D; Moodie, D; Kane, D

    2009-01-01

    A new optoelectronic sensor for the real time monitoring of key components such as valves and connectors within the subsea production equipment for leaks of hydraulic fluid is reported. The sensor is capable of detecting low concentrations of such fluids, allowing the early detection of small leaks, and the ability to monitor the evolution of the leak-rate with time, hence providing an important new tool in complying with environmental requirements, enabling early intervention and optimising subsea production

  15. Development of a novel and customizable two-solution mixing type spray nozzle for one-step preparation of nanoparticle-containing microparticles.

    Science.gov (United States)

    Ozeki, Tetsuya; Akiyama, Yusuke; Takahashi, Norimitsu; Tagami, Tatsuaki; Tanaka, Toshiyuki; Fujii, Masashi; Okada, Hiroaki

    2012-01-01

    Production of drug nanoparticles is an effective strategy to enhance solubility and oral absorption of water-insoluble drugs. The handling of drug nanoparticles has been an important issue in drug formulation because nanoparticles easily aggregate each other and redispersion of these particles is very difficult. In the present study, we developed a unique two-solution mixing type spray nozzle that can prepare drug nanoparticles in microparticles in one step without any common solvent and surfactant, and then, the prepared formulation were evaluated. Ethylcellulose (EC) and mannitol (MAN) were used as a model polymer of water-insoluble compound and a water-soluble carrier, respectively. We characterized the EC/MAN microparticles produced by the novel spray nozzle when customizing the nozzle parts to mix EC and MAN solution. Relatively smaller EC nanoparticles (customizable parts in the nozzle. In addition, the core of EC nanoparticles (<50 nm) was also observed by atomic force microscopy. We also found that the mixing time in the nozzle parts affected the size and the standard deviation of EC nanoparticles. These results suggest that the size of EC nanoparticles in MAN microparticles is controllable by using this unique nozzle. After all, we could prepare MAN microparticles containing EC nanoparticles in one step by using the novel nozzle. The drug/MAN microparticles formulation produced by the nozzle may be useful for the handling of drug nanoparticles.

  16. Development of sodium leak detectors for PFBR

    International Nuclear Information System (INIS)

    Sylvia, J.I.; Rao, P. Vijayamohana; Babu, B.; Madhusoodanan, K.; Rajan, K.K.

    2012-01-01

    Highlights: ► Sodium leak detection system developed for PFBR using diverse principle. ► Miniature, remotely locatable diverse leak detector developed for Main Vessel. ► Mutual inductance type leak detectors designed and adapted for different locations. ► Sodium Ionisation detectors used for area monitoring. ► Crosswire type leak detector designed, developed and tested. - Abstract: The 500 MWe Prototype Fast Breeder Reactor (PFBR) is under advanced stage of construction at Kalpakkam near Chennai in India. The wide and high operating temperature, highly chemically active nature of sodium and its reaction with air make the sodium instrumentation complex over the conventional instrumentation. Over the years, traditional instruments such as wire type leak detectors, spark plug type leak detectors were developed and used in different sodium systems. The redundant and diverse leak detection method calls for development of special instrumentation for sodium systems which include sodium ionization (leak) detector for detecting minute sodium leak in addition to those systems based on mutual inductance principle. For detection of sodium leak from reactor Main Vessel (MV), diverse methods are used such as miniature, remotely locatable, Mutual Inductance type Leak Detector(MILD) and specially modified spark plug type leak detector. The design of MILD is suitably modified for detecting leak in double wall pipes and Diverse Safety Rod drive Mechanism (DSRDM). Steam/water leak in steam generator produces hydrogen and leads to high pressure and temperature in the system. Rupture disc is used as a safety device which punctures itself due to sudden pressure rise. To detect the discharge of sodium and its reaction products at the downstream of the rupture disc due to bursting of the rupture disc, cross wire type leak detector has been designed, developed and tested. The selection of the leak detection system depends on the location where leak has to be detected. This paper

  17. Monitoring plan for characterization of the Building 3019 leak site

    International Nuclear Information System (INIS)

    1986-06-01

    The Oak Ridge National Laboratory (ORNL) has established a Remedial Action Program to provide comprehensive management of areas where past research, development, and waste management activities have resulted in residual contamination of facilities or the environment. In the winter of 1985, elevated levels of strontium-90 were detected in White Oak Creek and the ORNL sewage treatment plant. A leak was subsequently identified in a low-level waste transfer line north of Building 3019. The period of leakage and the exact chemical composition of the effluent are unknown. Two dye tests conducted at the leak site have identified several possible pathways for contaminant migration. The discovery of a solution cavity in the Chickamauga bedrock underlying the leak site and the rapid appearance of dye in the sump at Building 3042 indicate the extension of the cavity system along strike to the east. This report outlines the available published and unpublished background information pertaining to the site and proposes a monitoring plan consisting of soil sample collection and monitor well installation to provide a preliminary assessment of the types and extent of contamination at the leak site. The plan is also designed to provide additional geologic and hydrologic data for evaluating possible contaminant migration pathways. 6 refs., 10 figs., 1 tab

  18. Applicability of fan spray nozzles to stripping insoluble gases from viscous liquids

    International Nuclear Information System (INIS)

    Tseng, H.H.; Johnson, E.F.

    1983-08-01

    Fan spray nozzle stripping appears to be a practical technique for separating dilute volatile solutes from nonvolatile solvents. In particular this technique can be used to strip molecular tritium and tritium fluoride at extremely small concentration (in the parts per million range) from molten salts used as blanket materials in a fusion reactor. Under adjusted operating conditions of the fan spray as it leaves the nozzle, a high percentage of the theoretically maximum achievable stripping would take place from the expanding sheet of the fan spray as it leaves the nozzle and before it breaks up. Although the only available experimental data are for aqueous solutions, a new theoretical analysis of the fan spray sheet demonstrates the applicability of this technique to nonaqueous liquids. The equation derived from this analysis relates the theoretically achievable mass transfer efficiency to the properties of the liquid flowing through the fan spray nozzle and to the operating conditions of the nozzle. Any fluid with viscosity higher than or equal to that of water would be expected to follow this equation as long as a fan-shaped sheet is formed under the operating conditions of the nozzle

  19. Evaluation of methodologies for the calculation of leak rates for pressure retaining components with crack-like leaks; Bewertung von Methoden zur Berechnung von Leckraten fuer druckfuehrende Komponenten mit rissartigen Lecks

    Energy Technology Data Exchange (ETDEWEB)

    Sievers, Juergen; Heckmann, Klaus; Blaesius, Christoph

    2015-06-15

    For the demonstration of break preclusion for pressure retaining components in nuclear power plants, the nuclear safety standard KTA 3206 determines also the requirements for the leak-before-break verification. For this procedure, it has to be ensured that a wall-penetrating crack is subcritical with respect to instable growth, and that the resulting leakage under stationary operation conditions can be detected by a leak detection system. Within the scope of the project 3613R01332 analyses with respect to conservative estimates of the leak rates in case of detections regarding break preclusion were performed by means of leak rate models being available at GRS. For this purpose, conservative assumptions in the procedure were quantified by comparative calculations concerning selected leak rate experiments and the requirements regarding the determination of leak rates indicated in the KTA 3206 were verified and specified. Moreover, the models were extended and relevant recommendations for the calculation procedure were developed. During the investigations of leak rate tests the calculation methods were validated, qualified by means of both examples indicated in KTA 3206 and applied to a postulated leak accident in the cooling circuit of a PWR. For the calculation of leak rates several simplified solution methods which are included in the GRS program WinLeck were applied, and for the simulation of a leak accident the large-scale programs ANSYS Mechanical and ATHLET (thermohydraulics program developed by GRS) were used. When applying simplified methods for the calculation of leak rates using the limiting curve for the friction factor which has been derived during the project and which is included in the KTA 3206 attention has to be paid to the fact that in case of small flow lengths the entrance loss can dominate compared to the friction loss. However, the available data do not suffice in order to make a quantitative statement with respect to limits of applicability

  20. Leak detection method

    International Nuclear Information System (INIS)

    1978-01-01

    This invention provides a method for removing nuclear fuel elements from a fabrication building while at the same time testing the fuel elements for leaks without releasing contaminants from the fabrication building or from the fuel elements. The vacuum source used, leak detecting mechanism and fuel element fabrication building are specified to withstand environmental hazards. (UK)

  1. Leak Isolation in Pressurized Pipelines using an Interpolation Function to approximate the Fitting Losses

    Science.gov (United States)

    Badillo-Olvera, A.; Begovich, O.; Peréz-González, A.

    2017-01-01

    The present paper is motivated by the purpose of detection and isolation of a single leak considering the Fault Model Approach (FMA) focused on pipelines with changes in their geometry. These changes generate a different pressure drop that those produced by the friction, this phenomenon is a common scenario in real pipeline systems. The problem arises, since the dynamical model of the fluid in a pipeline only considers straight geometries without fittings. In order to address this situation, several papers work with a virtual model of a pipeline that generates a equivalent straight length, thus, friction produced by the fittings is taking into account. However, when this method is applied, the leak is isolated in a virtual length, which for practical reasons does not represent a complete solution. This research proposes as a solution to the problem of leak isolation in a virtual length, the use of a polynomial interpolation function in order to approximate the conversion of the virtual position to a real-coordinates value. Experimental results in a real prototype are shown, concluding that the proposed methodology has a good performance.

  2. Investigation for the sodium leak in Monju. Sodium leak and fire test-1

    International Nuclear Information System (INIS)

    Kawata, Koji; Ohno, Shuji; Miyahara, Shinya; Miyake, Osamu; Tanabe, Hiromi

    2000-08-01

    As a part of the work for investigating the sodium leak accident which occurred in the Monju reactor (hereinafter referred to as Monju) on December 8, 1995, three tests, (1) a sodium leak test, (2) a sodium leak and fire test-1, and (3) a sodium leak and fire test-II, were carried out at OEC/PEC. The main objectives of these tests were to confirm the leak and burning behavior of sodium from the damaged thermometer, and the effects of the sodium fire on the integrity of the surrounding structure. This report describes the results of the sodium fire test-I carried out as a preliminary test. The test was performed using the SOLFA-2 (Sodium Leak, Fire and Aerosol) facility on April 8, 1996. In this test, sodium heated to 480degC was leaked for approximately 1.5 hours from a leak simulating apparatus and caused to drop onto a ventilation duct and a grating with the same dimensions and layout as those in Monju. The main conclusions obtained from the test are shown below: 1) Observation from video cameras in the test revealed that in the early stages of the sodium leak, sodium dripped out of the flexible tube of the thermometer. This dripping and burning expanded in range as the sodium splashed on the duct. 2) No damage to the duct itself was detected. However, the aluminum louver frame of the ventilation duct's lower inlet was damaged. Its machine screws came off, leaving half of the grill (on the grating side) detached. 3) No large hole, like the one seen at Monju, was found when the grating was removed from the testing system for inspection, although the area centered on the point were the sodium dripped was damaged in a way indicating the first stages of grating failure. The 5mm square lattice was corroded through in some parts, and numerous blades (originally 3.2 mm thick) had become sharpened like the blade of a knife. 4) The burning pan underside thermocouple near the leak point measured 700degC in within approximately 10 minutes, and for the next hour remained

  3. High-voltage leak detection of a parenteral proteinaceous solution product packaged in form-fill-seal plastic laminate bags. Part 2. Method performance as a function of heat seal defects, product-package refrigeration, and package plastic laminate lot.

    Science.gov (United States)

    Rasmussen, Mats; Damgaard, Rasmus; Buus, Peter; Mulhall, Brian; Guazzo, Dana Morton

    2013-01-01

    Part 1 of this three-part research series detailed the development and validation of a high-voltage leak detection test (HVLD, also known as an electrical conductivity and capacitance test) for verifying the container-closure integrity of a small-volume laminate plastic bag containing an aqueous solution formulation of the rapid-acting insulin analogue, insulin aspart (NovoRapid®/NovoLog®) by Novo Nordisk A/S, Bagsværd, Denmark. Leak detection capability was verified using positive controls each with a single laser-drilled hole in the bag film face. In this Part 2, HVLD leak detection capability was further explored in four separate studies. Study 1 investigated the ability of HVLD to detect weaknesses and/or gaps in the bag heat seal. Study 2 checked the HVLD detection of bag holes in packages stored 4 days at ambient conditions followed by 17 days at refrigeration. Study 3 examined HVLD test results for packages tested when cold. Study 4 compared HVLD test results as a function of bag plastic film lots. The final Part 3 of this series will report the impact of HVLD exposure on product visual appearance and chemical stability. In Part 1 of this three-part series, a leak test method based on electrical conductivity and capacitance, also called high-voltage leak detection (HVLD), was used to find leaks in small plastic bags filled with a solution for injection of the rapid-acting insulin analogue, insulin aspart (NovoRapid®/NovoLog®) by Novo Nordisk A/S, Bagsværd, Denmark. In this Part 2, HVLD leak detection capability was further explored in four separate studies. Study 1 investigated the ability of HVLD to detect bag heat seal leaks. Study 2 checked HVLD's ability to detect bag holes after a total of 21 days at ambient plus refrigerated temperatures. Study 3 looked to see if HVLD results changed for packages tested when still cold. Study 4 compared HVLD results for multiple bag plastic film lots. The final Part 3 of this series will report any evidence of

  4. Defect-Free Large-Area (25 cm2 Light Absorbing Perovskite Thin Films Made by Spray Coating

    Directory of Open Access Journals (Sweden)

    Mehran Habibi

    2017-03-01

    Full Text Available In this work, we report on reproducible fabrication of defect-free large-area mixed halide perovskite (CH3NH3PbI3−xClx thin films by scalable spray coating with the area of 25 cm2. This is essential for the commercialization of the perovskite solar cell technology. Using an automated spray coater, the film thickness and roughness were optimized by controlling the solution concentration and substrate temperature. For the first time, the surface tension, contact angle, and viscosity of mixed halide perovskite dissolved in dimethylformamide (DMF are reported as a function of the solution concentration. A low perovskite solution concentration of 10% was selected as an acceptable value to avoid crystallization dewetting. The determined optimum substrate temperature of 150 °C, followed by annealing at 100 °C render the highest perovskite precursor conversion, as well as the highest possible droplet spreading, desired to achieve a continuous thin film. The number of spray passes was also tuned to achieve a fully-covered film, for the condition of the spray nozzle used in this work. This work demonstrates that applying the optimum substrate temperature decreases the standard deviation of the film thickness and roughness, leading to an increase in the quality and reproducibility of the large-area spray-on films. The optimum perovskite solution concentration and the substrate temperature are universally applicable to other spray coating systems.

  5. Analysis of small leaks

    International Nuclear Information System (INIS)

    Frisch, W.; Hofmann, K.

    1979-01-01

    Problems associated with 'small leaks' are described and requirements are derived for experimental facilities and computer codes. Based on these requirements, a valuation of the existing experimental facilities and codes is presented. Facilities for integral tests in relatively large scale (ex. LOFT) are suitable for small leak test in principle, however minor changes (instrumentation, secondary side) are necessary for the evaluation of certain phenomena. The 'advanced blowdown codes' are capable of describing most of the phenomena occurring during small leak events, however a substantial amount of code development and verification is still needed. In addition, the use of transient codes in small leak analysis is demonstrated. There are some areas (neutronics feedback, influence of control system) in which the use of transient codes is possible and advantageous. (orig.) 891 HP/orig. 892 BRE [de

  6. Leak rate measurements and detection systems

    International Nuclear Information System (INIS)

    Kupperman, D.; Shack, W.J.; Claytor, T.

    1983-10-01

    A research program is under way to evaluate and develop improve leak detection systems. The primary focus of the work has been on acoustic emission detection of leaks. Leaks from artificial flaws, laboratory-generated IGSCCs and thermal fatigue cracks, and field-induced intergranular stress corrosion cracks (IGSCCs) from reactor piping have been examined. The effects of pressure, temperature, and leak rate and geometry on the acoustic signature are under study. The use of cross-correlation techniques for leak location and pattern recognition and autocorrelation for source discrimination is also being considered

  7. Fabrication of ultra-sensitive leak detection standards

    International Nuclear Information System (INIS)

    Winkelman, C.R.

    1980-01-01

    The primary difficulty with flow rate measurements below 10 -10 standard cubic centimeters per second (std. cc/sec) is that there are no commercially available standards. The requirements, however, dictate that the problem of design and construction of a qualifiable standard in the ultra-sensitive range had to be solved. There are a number of leak types which were considered - capillary leaks, orifice leaks, and the pore type leaks, among others. The capillary leak was not used because of the cracking or sorting effects that are common to this type leak. For example, a gas blend flowing through a capillary leak will result in the lighter gases passing through the leak first. The difficulty of fabricating the proper hole size in relation to the flow rate requirements ruled out the orifice type leak. The choice was the pore type leak which utilizes the basic concept of a stainless steel knife edge driven into a fixed section composed of stainless steel with a gold over-lay and maintained under force

  8. Numerical model of sprayed air cooled condenser coupled to refrigerating system

    International Nuclear Information System (INIS)

    Youbi-Idrissi, M.; Macchi-Tejeda, H.; Fournaison, L.; Guilpart, J.

    2007-01-01

    Because of technological, economic and environmental constraints, many refrigeration and air conditioning units are equipped with a simple air cooled condenser. Spraying the condenser seems to be an original solution to improve the energetic performances of such systems. To characterise this energetic benefit, a semi-local mathematical model was developed and applied to a refrigerating machine with and without spraying its air cooled condenser. It is found that, compared to a dry air cooled condenser, both the calorific capacity and machine COP increase by 13% and 55%, respectively. Furthermore, the model shows that a spray flow rate threshold occurs. It should not be exceeded to assure an effective and rational spray use

  9. Summary of PWR leak detection studies

    International Nuclear Information System (INIS)

    Cho, J.H.; Elia, F.A. Jr.

    1986-01-01

    Thermal-hydraulic analysis can be used to determine the location and magnitude of leaks inside and location of leaks outside a pressurized water reactor (PWR) containment as required by plant technical specifications. The major advantage of this detection method is that it minimizes radiation exposure of maintenance personnel because most of the leak detection process is performed from the control room outside containment. Plant-specific analyses are utilized to predict change in parameters such as local dew point temperature, relative humidity, dry bulb temperature, and flow rate to sump for various leak rates and enthalpies. These parameter responses are then programmed into the plant computer and instrumentation is provided for area monitoring. The actual inputs are continuously monitored and compared to the predicted plant responses to identify the leak location and quantify the leak. This study concludes that a system that monitors dew point (or relative humidity) and dry bulb temperature changes together with the flow rate to the sump will provide the capability to both locate and quantify a leak inside a containment, while a system that monitors dew point temperature (or relative humidity) changes will provide the capability to locate a leak outside a containment

  10. Plutonium solution storage in plastic bottles: Operational experience and safety issues

    International Nuclear Information System (INIS)

    Conner, W.V.

    1995-01-01

    Computer spread sheet models were developed to gain a better understanding of the factors that lead to pressurization and failure of plastic bottles containing plutonium solutions. These models were developed using data obtained from the literature on gas generation rates for plutonium solutions. Leak rates from sealed plastic bottles were obtained from bottle leak tests conducted at Rocky Flats. Results from these bottle leak tests showed that narrow mouth four liter bottles will seal much better than wide mouth four liter bottles. The gas generation rate and leak rate data were used to develop models for predicting the rate of pressurization and maximum pressures expected in sealed bottles of plutonium solution containing various plutonium and acid concentrations. The computer models were used to develop proposed time limits for storing or transporting plutonium solutions in sealed plastic bottles. For plutonium solutions containing 1.5 g/l plutonium, storage in sealed bottles should not be allowed. However, transportation of higher concentration plutonium solution in sealed bottles is required, and safe transportation times of 1 shift to 6 days are proposed

  11. Effect of the number of calcium chloride sprays on 'Jonagold' apple quality

    Directory of Open Access Journals (Sweden)

    Paweł Wójcik

    2013-12-01

    Full Text Available The aim of this study was to examine effect of frequency of calcium chloride (CaCl2 sprays on 'Jonagold' apple (Malus domestica Borkh. quality. The experiment was carried out in 1996-1998 in the Experimental Orchard of the Research Institute of Pomology and Floriculture in Skierniewice. Apple trees were grafied on M.26 rootstock and planted in 1992 at a distance of 4 x 2 m on a sandy loam soil with high available phosphorus, potassium and magnesium contents. Four experimental treatments were applied: (i three sprays with CaCl2 solutions at 2, 10 and 18 weeks after full bloom, (ii six sprays with CaCl2 at 2, 6, 10, 14, 16 and 18 weeks after full bloom, (iii nine sprays with CaCl2 at 2, 4, 6, 8, 10, 12, 14, 16 and 18 weeks after full bloom and (iv control plot - trees unsprayed with CaCl2. The results showed that fruit Ca concentration increased with the number of CaCl2 sprays during the growing season. Apples nine-times sprayed with CaCl2 solutions were smaller, less mature at harvest and after storage, had lower titratable acidity and soluble solids contents after storage and were less sensitive to bitter pit, internal breakdown and Gloeosporium-rot compared to other treatments; however these effects were influenced by the growing season. Six CaCl2 sprays only in one year of the study increased fruit firmness after storage, fruit resistance to bitter pit and internal breakdown. Three CaCl2 sprays decreased bitter pit incidence; however this effect was found only in one investigated year.

  12. Nuclear fuel element leak detection system

    International Nuclear Information System (INIS)

    John, C.D. Jr.

    1978-01-01

    Disclosed is a leak detection system integral with a wall of a building used to fabricate nuclear fuel elements for detecting radiation leakage from the nuclear fuel elements as the fuel elements exit the building. The leak detecting system comprises a shielded compartment constructed to withstand environmental hazards extending into a similarly constructed building and having sealed doors on both ends along with leak detecting apparatus connected to the compartment. The leak detecting system provides a system for removing a nuclear fuel element from its fabrication building while testing for radiation leaks in the fuel element

  13. Comparison of enterotomy leak pressure among fresh, cooled, and frozen-thawed porcine jejunal segments.

    Science.gov (United States)

    Aeschlimann, Kimberly A; Mann, F A; Middleton, John R; Belter, Rebecca C

    2018-05-01

    OBJECTIVE To determine whether stored (cooled or frozen-thawed) jejunal segments can be used to obtain dependable leak pressure data after enterotomy closure. SAMPLE 36 jejunal segments from 3 juvenile pigs. PROCEDURES Jejunal segments were harvested from euthanized pigs and assigned to 1 of 3 treatment groups (n = 12 segments/group) as follows: fresh (used within 4 hours after collection), cooled (stored overnight at 5°C before use), and frozen-thawed (frozen at -12°C for 8 days and thawed at room temperature [23°C] for 1 hour before use). Jejunal segments were suspended and 2-cm enterotomy incisions were made on the antimesenteric border. Enterotomies were closed with a simple continuous suture pattern. Lactated Ringer solution was infused into each segment until failure at the suture line was detected. Leak pressure was measured by use of a digital transducer. RESULTS Mean ± SD leak pressure for fresh, cooled, and frozen-thawed segments was 68.3 ± 23.7 mm Hg, 55.3 ± 28.1 mm Hg, and 14.4 ± 14.8 mm Hg, respectively. Overall, there were no significant differences in mean leak pressure among pigs, but a significant difference in mean leak pressure was detected among treatment groups. Mean leak pressure was significantly lower for frozen-thawed segments than for fresh or cooled segments, but mean leak pressure did not differ significantly between fresh and cooled segments. CONCLUSIONS AND CLINICAL RELEVANCE Fresh porcine jejunal segments or segments cooled overnight may be used for determining intestinal leak pressure, but frozen-thawed segments should not be used.

  14. The detection of leaks on sodium pipes in a 'leak before break' approach

    International Nuclear Information System (INIS)

    Antonakas, D.

    1989-01-01

    The operation of circuits containing liquid sodium requires, given the chemical affinity of this fluid for air and water, a reliable detection of possible leaks. This system of detection should alert the operators to the occurrence of a leak in sufficient time to limit the potential consequences of a discharge of sodium in the building, leading to a severe sodium fire or at least to an extended corrosion of the pipe system. From a design point of view, the most likely event leading to this situation can be the consequence. of an initial undetected defect which develops under the effect of thermo-mechanical loadings, produces a sodium. leak below the dejection threshold remains undetectable white progressing and finally leads to a guillotine-type rupture when an incidental loading is superimposed to the normal one. The 'leak before break' approach which is now currently introduced in design considerations consists of insuring the detection of incipient leaks corresponding to through-the-wall cracks well below instability of the pipe. Under this short statement, lies a considerable and still necessary effort of research broadly presented in the present paper

  15. Optimization of spray deposition and Tetranychus urticae control with air assisted and electrostatic sprayer

    Directory of Open Access Journals (Sweden)

    Denise Tourino Rezende de Cerqueira

    Full Text Available ABSTRACT: Improved spray deposition can be attained by electrostatically charging spray droplets, which increases the attraction of droplets to plants and decreases operator exposure to pesticide and losses to the environment. However, this technique alone is not sufficient to achieve desirable penetration of the spray solution into the crop canopy; thus, air assistance can be added to the electrostatic spraying to further improve spray deposition. This study was conducted to compare different spraying technologies on spray deposition and two-spotted spider mite control in cut chrysanthemum. Treatments included in the study were: conventional TJ 8003 double flat fan nozzles, conventional TXVK-3 hollow cone nozzles, semi-stationary motorized jet launched spray with electrostatic spray system (ESS and air assistance (AA, and semi-stationary motorized jet launched spray with AA only (no ESS. To evaluate the effect of these spraying technologies on the control of two-spotted spider mite, a control treatment was included that did not receive an acaricide application. The AA spraying technology, with or without ESS, optimized spray deposition and provided satisfactory two-spotted spider mite control up to 4 days after application.

  16. Water leak localization and recovery in Tore Supra

    International Nuclear Information System (INIS)

    Martinez, A.; Samaille, F.; Chantant, M.; Hatchressian, J.C.

    2007-01-01

    For almost 20 years at Tore Supra, plasma facing components (PFCs) are actively cooled by a pressurized water primary loop. Tore Supra can be considered as ITER relevant on this particular aspect. During plasma operation, it happened, that unexpected localized power deposits damaged a PFC leading to more or less large water leaks in the vacuum vessel. The improvement of the procedure to localize the leaky circuits, the investigation of technical solutions for minimizing the amount of water from steam condensation in the vacuum vessel and the optimisation of the quality of the draining and the drying of Tore Supra cooling loop circuits are the result of the experience gained during several years by the analysis of the water leak from plasma facing components (PFCs) and their consequences. Different new specific systems designed and installed during this year to fulfil these objectives are described in this paper

  17. Hermetic Seal Leak Detection Apparatus

    Science.gov (United States)

    Kelley, Anthony R. (Inventor)

    2013-01-01

    The present invention is a hermetic seal leak detection apparatus, which can be used to test for hermetic seal leaks in instruments and containers. A vacuum tight chamber is created around the unit being tested to minimize gas space outside of the hermetic seal. A vacuum inducing device is then used to increase the gas chamber volume inside the device, so that a slight vacuum is pulled on the unit being tested. The pressure in the unit being tested will stabilize. If the stabilized pressure reads close to a known good seal calibration, there is not a leak in the seal. If the stabilized pressure reads closer to a known bad seal calibration value, there is a leak in the seal. The speed of the plunger can be varied and by evaluating the resulting pressure change rates and final values, the leak rate/size can be accurately calculated.

  18. Damage phenomena at target surface by small leak

    International Nuclear Information System (INIS)

    Jeong, Kyung Chai; Jeong, J. Y.; Kim, B. H.; Kim, T. J.; Choi, J. H.

    2001-04-01

    Design of the steam generator should be considered the safety about the sodium-water reaction occurred by water leak in heat transfer tube. Water leak mainly occurred from welding defect at the process of tube connection, the vibration of heat transfer tube bundle in steam generating system, fretting, and pin hole in original tube manufacturing. The classification of water leak divided to two parts, roughly, in case of the water leak studies. One is small leak phenomena analysis, and the other is it of large leak which was mainly treated to the evaluation on pressure increasing from hydrogen gas formed by sodium-water reaction in sodium system. In small water leak, the leak propagation phenomena and the development of leak detecting system at initial stage of small water leak were studied, mainly. In this study, the corrosion phenomena on the target tube surface appeared by sodium-water reaction was analyzed through the small water leak experiments, and, also, the jet phenomena formed by N 2 gas injection through the leak nozzle under water medium was observed

  19. Paravalvular Leak in Structural Heart Disease.

    Science.gov (United States)

    Goel, Kashish; Eleid, Mackram F

    2018-03-06

    This review will summarize the growing importance of diagnosing and managing paravalvular leak associated with surgical and transcatheter valves. The burden of paravalvular leak is increasing; however, advanced imaging techniques and high degree of clinical suspicion are required for diagnosis and management. The latest data from pivotal clinical trials in the field of transcatheter aortic valve replacement suggest that any paravalvular leak greater than mild was associated with worse clinical outcomes. Percutaneous techniques for paravalvular leak closure are now the preferred approach, and surgical repair is reserved for contraindications and unsuccessful procedures. Recent data from studies evaluating paravalvular leak closure outcomes report a greater than 90% success rate with a significant improvement in patient symptoms. Paravalvular leak is a growing problem in the structural heart disease arena. Percutaneous closure is successful in more than 90% of the procedures with a low complication rate.

  20. Leak detection by vibrational diagnostic methods

    International Nuclear Information System (INIS)

    Siklossy, P.

    1983-01-01

    The possibilities and methods of leak detection due to mechanical failures in nuclear power plants are reviewed on the basis of the literature. Great importance is attributed to vibrational diagnostic methods for their adventageous characteristics which enable them to become final leak detecting methods. The problems of noise analysis, e.g. leak detection by impact sound measurements, probe characteristics, gain problems, probe selection, off-line analysis and correlation functions, types of leak noises etc. are summarized. Leak detection based on noise analysis can be installed additionally to power plants. Its maintenance and testing is simple. On the other hand, it requires special training and measuring methods. (Sz.J.)

  1. Traumatic orbital CSF leak

    Science.gov (United States)

    Borumandi, Farzad

    2013-01-01

    Compared to the cerebrospinalfluid (CSF) leak through the nose and ear, the orbital CSF leak is a rare and underreported condition following head trauma. We present the case of a 49-year-old woman with oedematous eyelid swelling and ecchymosis after a seemingly trivial fall onto the right orbit. Apart from the above, she was clinically unremarkable. The CT scan revealed a minimally displaced fracture of the orbital roof with no emphysema or intracranial bleeding. The fractured orbital roof in combination with the oedematous eyelid swelling raised the suspicion for orbital CSF leak. The MRI of the neurocranium demonstrated a small-sized CSF fistula extending from the anterior cranial fossa to the right orbit. The patient was treated conservatively and the lid swelling resolved completely after 5 days. Although rare, orbital CSF leak needs to be included in the differential diagnosis of periorbital swelling following orbital trauma. PMID:24323381

  2. α- and β-Carotene Stability During Storage of Microspheres Obtained from Spray-Dried Microencapsulation Technology

    Directory of Open Access Journals (Sweden)

    Przybysz Marzena Anna

    2018-03-01

    Full Text Available This study was aimed at comparing the stability of carotenes (α- and β-carotene in oil solutions with their stability when spray-dried encapsulation is applied. The carotenes were isolated from carrot. A storage test was subsequently performed. The stability of carotenes in oil solutions was determined with the HPLC method. The color of the samples was also analyzed. The oil solutions of carotenes were microencapsulated with the spray-drying method. A mixture of gum Arabic and maltodextrin was used as a matrix.

  3. New process of the preparation of catalyzed gas diffusion electrode for PEM fuel cells based on ultrasonic direct solution spray reaction method

    Energy Technology Data Exchange (ETDEWEB)

    Oishi, K.; Savadogo, O. [Ecole Polytechnique de Montreal, Montreal, PQ (Canada). Laboratoire de nouveaux materiaux pour l' energie et l' electrochimie

    2008-07-01

    This paper reported on a newly developed process for in-situ catalyst deposition on gas diffusion electrodes (GDE) for polymer electrolyte fuel cells. This process has the potential to reduce the number of steps for catalyzed GDE fabrication. In addition, the process offers economic advantages for the fuel cell commercialization. In this study, a home-made catalyst maker with ultrasonic spray method was used to prepare a solution of the carbon supported platinum catalyst on the GDL. The sprayed catalyst powder consisted of carbon support. The catalyst particles did not prevent gas flow channels on the GDL. The catalyst layer was shown to be located only on the top surface of the GDL and was not packed into its flow channel. Results of Cross-section SEM image, crystallization, micro structure and electro-catalytic activity for the oxygen reduction reaction were also discussed. 1 ref., 1 fig.

  4. Linear Stability Analysis of Laminar Premixed Fuel-Rich Double-Spray Flames

    Directory of Open Access Journals (Sweden)

    Noam Weinberg

    2014-03-01

    Full Text Available This paper considers the stability of a double-spray premixed flame formed when both fuel and oxidizer are initially present in the form of sprays of evaporating liquid droplets. To simplify the inherent complexity that characterizes the analytic solution of multi-phase combustion processes, the analysis is restricted to fuel-rich laminar premixed double-spray flames, and assumes a single-step global chemical reaction mechanism. Steady-state solutions are obtained and the sensitivity of the flame temperature and the flame propagating velocity to the initial liquid fuel and/or oxidizer loads are established. The stability analysis revealed an increased proneness to cellular instability induced by the presence of the two sprays, and for the fuel-rich case considered here the influence of the liquid oxidizer was found to be more pronounced than that of the liquid fuel. Similar effects were noted for the neutral pulsating stability boundaries. The impact of unequal latent heats of vaporization is also investigated and found to be in keeping with the destabilizing influence of heat loss due to droplet evaporation. It should be noted that as far as the authors are aware no experimental evidence is available for (at least validation of the predictions. However, they do concur in a general and reasonable fashion with independent experimental evidence in the literature of the behavior of single fuel spray laminar premixed flames.

  5. Effect of Corrosion Inhibitors on In Situ Leak Repair by Precipitation of Calcium Carbonate in Potable Water Pipelines.

    Science.gov (United States)

    Wang, Fei; Devine, Christina L; Edwards, Marc A

    2017-08-01

    Corrosion inhibitors can affect calcium carbonate precipitation and associated in situ and in-service water distribution pipeline leak repair via clogging. Clogging of 150 μm diameter leak holes represented by glass capillary tubes, in recirculating solutions that are supersaturated with calcite (Ω calcite = 13), demonstrated that Zn, orthophosphate, tripolyphosphate, and hexametaphosphate corrosion/scaling inhibitors hinder clogging but natural organic matter (NOM) has relatively little impact. Critical concentrations of phosphates that could inhibit leak repair over the short-term in one water tested were: tripolyphophate (0.05 mg/L as P) water systems.

  6. Photoelectrode Fabrication of Dye-Sensitized Nanosolar Cells Using Multiple Spray Coating Technique

    Directory of Open Access Journals (Sweden)

    Chien-Chih Chen

    2013-01-01

    Full Text Available This paper presents a spray coating technique for fabricating nanoporous film of photoelectrode in dye-sensitized nanosolar cells (DSSCs. Spray coating can quickly fabricate nanoporous film of the photoelectrode with lower cost, which can further help the DSSCs to be commercialized in the future. This paper analyzed photoelectric conversion efficiency of the DSSCs using spray coated photoelectrode in comparison with the photoelectrode made with the doctor blade method. Spray coating can easily control transmittance of the photoelectrode through the multiple spray coating process. This work mainly used a dispersant with help of ultrasonic oscillation to prepare the required nano-TiO2 solution and then sprayed it on the ITO glasses. In this work, a motor-operated conveyor belt was built to transport the ITO glasses automatically for multiple spray coating and drying alternately. Experiments used transmittance of the photoelectrode as a fabrication parameter to analyze photoelectric conversion efficiency of the DSSCs. The influencing factors of the photoelectrode transmittance during fabrication are the spray flow rate, the spray distance, and the moving speed of the conveyor belt. The results show that DSSC with the photoelectrode transmittance of ca. 68.0 ± 1.5% and coated by the spray coating technique has the best photoelectric conversion efficiency in this work.

  7. Imaging review of cerebrospinal fluid leaks

    OpenAIRE

    Naga V Vemuri; Lakshmi S P Karanam; Venkatesh Manchikanti; Srinivas Dandamudi; Sampath K Puvvada; Vineet K Vemuri

    2017-01-01

    Cerebrospinal fluid (CSF) leak occurs due to a defect in the dura and skull base. Trauma remains the most common cause of CSF leak; however, a significant number of cases are iatrogenic, and result from a complication of functional endoscopic sinus surgery (FESS). Early diagnosis of CSF leak is of paramount importance to prevent life-threatening complications such as brain abscess and meningitis. Imaging plays a crucial role in the detection and characterization of CSF leaks. Three-dimensiona...

  8. Quantitative and economical assessment of effectiveness of electrostatic pesticide spraying

    International Nuclear Information System (INIS)

    Nishimura, Ryo; Fujita, Satoko; Michihara, Shota; Masuoka, Takashi; Kimura, Toshihiro; Yatsuzuka, Shinji; Anaguchi, Shinobu

    2013-01-01

    Electrostatic pesticide spraying (EPS) improves the adhesion characteristics of the pesticide solution to agricultural crops. If the adhesion characteristics are improved, the requisite amount of the pesticide to be sprayed can be reduced in comparison with the conventional spraying method that uses non-charged pesticide. In this research, disease (rust) control experiments were carried out to substantiate the effectiveness of the EPS from a statistical point of view. We sprayed pesticide to potted Japanese pear trees under calm condition. The numbers of the rust lesions on the pear leaves were counted at fixed intervals after spraying to investigate the difference of the results of the disease control. The t-tests were carried out for the populations of the various spraying times and applied voltages. It was statistically-derived that EPS can reduce the amounts of pesticide to be sprayed by 50 % in comparison with the non-EPS method. It is also estimated from the results that about 55,000 kL year −1 of pesticides can be reduced for the Japanese pear cultivation in Tottori prefecture. Also, this means that the expense of the pear cultivation can be reduced by about 240 million yen (3 million USD) every year in Tottori prefecture by introducing EPS.

  9. Sodium leak at Monju (II): Sodium leak, burning and aerosol behavior

    International Nuclear Information System (INIS)

    Funada, T.; Yamagishi, Y.

    1996-01-01

    The amount of leaked sodium was estimated as approximately 640 kg during the 220 minute leak. The ventilation duct and the walkway grating under the leak site were severely damaged by Na-Fe-O reaction, but the floor liner and the concrete wall were not. A total 100 kg of sodium aerosol was deposited in the reactor auxiliary building and 230 kg was released to the atmosphere. The sodium concentration at the site boundary was calculated as 0.05 mg/m 3 , NaOH equivalent, which was low in comparison with the permitted level of 2 mg/m 3 . The tritium quantity released was estimated as 4.4 x 10 7 Bq, which was about 0.03% of the average released value per month for a LWR. (author)

  10. SCTI chemical leak detection test plan

    International Nuclear Information System (INIS)

    1981-01-01

    Tests will be conducted on the CRBRP prototype steam generator at SCTI to determine the effects of steam generator geometry on the response of the CRBRP chemical leak detection system to small water-to-sodium leaks in various regions of the steam generator. Specifically, small injections of hydrogen gas (simulating water leaks) will be made near the two tubesheets, and the effective transport times to the main stream exit and vent line hydrogen meters will be measured. The magnitude and time characteristics of the meters' response will also be measured. This information will be used by the Small Leak Protection Base Program (SG027) for improved predictions of meter response times and leak detection sensitivity

  11. 40 CFR 63.424 - Standards: Equipment leaks.

    Science.gov (United States)

    2010-07-01

    ....424 Standards: Equipment leaks. (a) Each owner or operator of a bulk gasoline terminal or pipeline... location of all equipment in gasoline service at the facility. (c) Each detection of a liquid or vapor leak... replacement of leaking equipment shall be completed within 15 calendar days after detection of each leak...

  12. Ammonia Leak Locator Study

    Science.gov (United States)

    Dodge, Franklin T.; Wuest, Martin P.; Deffenbaugh, Danny M.

    1995-01-01

    The thermal control system of International Space Station Alpha will use liquid ammonia as the heat exchange fluid. It is expected that small leaks (of the order perhaps of one pound of ammonia per day) may develop in the lines transporting the ammonia to the various facilities as well as in the heat exchange equipment. Such leaks must be detected and located before the supply of ammonia becomes critically low. For that reason, NASA-JSC has a program underway to evaluate instruments that can detect and locate ultra-small concentrations of ammonia in a high vacuum environment. To be useful, the instrument must be portable and small enough that an astronaut can easily handle it during extravehicular activity. An additional complication in the design of the instrument is that the environment immediately surrounding ISSA will contain small concentrations of many other gases from venting of onboard experiments as well as from other kinds of leaks. These other vapors include water, cabin air, CO2, CO, argon, N2, and ethylene glycol. Altogether, this local environment might have a pressure of the order of 10(exp -7) to 10(exp -6) torr. Southwest Research Institute (SwRI) was contracted by NASA-JSC to provide support to NASA-JSC and its prime contractors in evaluating ammonia-location instruments and to make a preliminary trade study of the advantages and limitations of potential instruments. The present effort builds upon an earlier SwRI study to evaluate ammonia leak detection instruments [Jolly and Deffenbaugh]. The objectives of the present effort include: (1) Estimate the characteristics of representative ammonia leaks; (2) Evaluate the baseline instrument in the light of the estimated ammonia leak characteristics; (3) Propose alternative instrument concepts; and (4) Conduct a trade study of the proposed alternative concepts and recommend promising instruments. The baseline leak-location instrument selected by NASA-JSC was an ion gauge.

  13. Imaging review of cerebrospinal fluid leaks.

    Science.gov (United States)

    Vemuri, Naga V; Karanam, Lakshmi S P; Manchikanti, Venkatesh; Dandamudi, Srinivas; Puvvada, Sampath K; Vemuri, Vineet K

    2017-01-01

    Cerebrospinal fluid (CSF) leak occurs due to a defect in the dura and skull base. Trauma remains the most common cause of CSF leak; however, a significant number of cases are iatrogenic, and result from a complication of functional endoscopic sinus surgery (FESS). Early diagnosis of CSF leak is of paramount importance to prevent life-threatening complications such as brain abscess and meningitis. Imaging plays a crucial role in the detection and characterization of CSF leaks. Three-dimensional, isotropic, high resolution computed tomography (HRCT) accurately detects the site and size of the bony defect. CT cisternography, though invasive, helps accurately identify the site of CSF leak, especially in the presence of multiple bony defects. Magnetic resonance imaging (MRI) accurately detects CSF leaks and associated complications such as the encephaloceles and meningoceles. In this review, we emphasize the importance and usefulness of 3D T2 DRIVE MR cisternography in localizing CSF leaks. This sequence has the advantages of effective bone and fat suppression, decreased artefacts, faster acquisition times, three-dimensional capability, y and high spatial resolution in addition to providing very bright signal from the CSF.

  14. Imaging review of cerebrospinal fluid leaks

    Directory of Open Access Journals (Sweden)

    Naga V Vemuri

    2017-01-01

    Full Text Available Cerebrospinal fluid (CSF leak occurs due to a defect in the dura and skull base. Trauma remains the most common cause of CSF leak; however, a significant number of cases are iatrogenic, and result from a complication of functional endoscopic sinus surgery (FESS. Early diagnosis of CSF leak is of paramount importance to prevent life-threatening complications such as brain abscess and meningitis. Imaging plays a crucial role in the detection and characterization of CSF leaks. Three-dimensional, isotropic, high resolution computed tomography (HRCT accurately detects the site and size of the bony defect. CT cisternography, though invasive, helps accurately identify the site of CSF leak, especially in the presence of multiple bony defects. Magnetic resonance imaging (MRI accurately detects CSF leaks and associated complications such as the encephaloceles and meningoceles. In this review, we emphasize the importance and usefulness of 3D T2 DRIVE MR cisternography in localizing CSF leaks. This sequence has the advantages of effective bone and fat suppression, decreased artefacts, faster acquisition times, three-dimensional capability, y and high spatial resolution in addition to providing very bright signal from the CSF.

  15. The Effects of Silk Protein Solution on Quality of Mangosteen

    International Nuclear Information System (INIS)

    Phadvibulya, Valailak; Sudatis, Boonya; Panyarum, Kanyarat; Junsaithong, Mayuree; Kerdchoechuen, Orapin

    2011-06-01

    Full text: Sericin silk protein solution prepared from irradiated silk waste was applied as a wax coating on mangosteen fruits but was found not appropriate. Nonetheless, when the solution was sprayed onto fruits from the setting stage till maturity, it enhanced the fruit quality. Fruits showed a bigger stalk and greener, thicker and larger-angled calyx than untreated ones. They were edible after being kept at 25 C for 3 to 4 weeks. Fruits sprayed with the silk protein solution and untreated fruits were separately harvested and packed for export. A half of them were irradiated with gamma radiation for insect eradication and then kept at 10 C with 80 percents relative humidity. The unirradiated half was stored similarly. Results showed that rind color of irradiated fruits changed slower than unirradiated ones. However, silk protein solution spraying and irradiation did not affect fruit firmness and total soluble solids of mangosteen flesh. For sensory evaluation, it was found that sprayed and irradiated fruits showed no differences from the untreated ones in their physical properties, color, taste and odor. Fruits sprayed with the silk protein solution without irradiation had the longest shelf life of 6 weeks

  16. The Effects of Silk Protein Solution on Quality of Mangosteen

    Energy Technology Data Exchange (ETDEWEB)

    Phadvibulya, Valailak; Sudatis, Boonya; Panyarum, Kanyarat; Junsaithong, Mayuree [Thailand Institute of Nuclear Technology, Nakhon Nayok, (Thailand); Kerdchoechuen, Orapin [School of Bioresources and Technology, King Mongkuts University, Bangkok (Thailand)

    2011-06-15

    Full text: Sericin silk protein solution prepared from irradiated silk waste was applied as a wax coating on mangosteen fruits but was found not appropriate. Nonetheless, when the solution was sprayed onto fruits from the setting stage till maturity, it enhanced the fruit quality. Fruits showed a bigger stalk and greener, thicker and larger-angled calyx than untreated ones. They were edible after being kept at 25{sup C} for 3 to 4 weeks. Fruits sprayed with the silk protein solution and untreated fruits were separately harvested and packed for export. A half of them were irradiated with gamma radiation for insect eradication and then kept at 10{sup C} with 80 percents relative humidity. The unirradiated half was stored similarly. Results showed that rind color of irradiated fruits changed slower than unirradiated ones. However, silk protein solution spraying and irradiation did not affect fruit firmness and total soluble solids of mangosteen flesh. For sensory evaluation, it was found that sprayed and irradiated fruits showed no differences from the untreated ones in their physical properties, color, taste and odor. Fruits sprayed with the silk protein solution without irradiation had the longest shelf life of 6 weeks.

  17. Measurement of Ambient Air Motion of D. I. Gasoline Spray by LIF-PIV

    Science.gov (United States)

    Yamakawa, Masahisa; Isshiki, Seiji; Yoshizaki, Takuo; Nishida, Keiya

    Ambient air velocity distributions in and around a D. I. gasoline spray were measured using a combination of LIF and PIV techniques. A rhodamine and water solution was injected into ambient air to disperse the fine fluorescent liquid particles used as tracers. A fuel spray was injected into the fluorescent tracer cloud and was illuminated by an Nd: YAG laser light sheet (532nm). The scattered light from the spray droplets and tracers was cut off by a high-pass filter (>560nm). As the fluorescence (>600nm) was transmitted through the high-pass filter, the tracer images were captured using a CCD camera and the ambient air velocity distribution could be obtained by PIV based on the images. This technique was applied to a D. I. gasoline spray. The ambient air flowed up around the spray and entered into the tail of the spray. Furthermore, the relative velocity between the spray and ambient air was investigated.

  18. Optical and electrical characteristics of zirconium oxide thin films deposited on silicon substrates by spray pyrolysis

    International Nuclear Information System (INIS)

    Aguilar-Frutis, M.; Araiza, J.J.; Falcony, C.; Garcia, M.

    2002-01-01

    The optical and electrical characteristics of zirconium oxide thin films deposited by spray pyrolysis on silicon substrates are reported. The films were deposited from a spraying solution of zirconium acetylacetonate in N,N-dimethylformamide using an ultrasonic mist generator on (100) Si substrates. The substrate temperature during deposition was in the range of 400 to 600 grad C. Deposition rates up to 16 A/sec were obtained depending on the spraying solution concentration and on the substrate temperature. A refraction index of the order of 2.0 was measured on these films by ellipsometry. The electrical characteristics of the films were determined from the capacitance and current versus voltage measurements. The addition of water mist during the spraying deposition process was also studied in the characteristics of the films. (Authors)

  19. Large-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Bontha, Jagannadha R.; Daniel, Richard C.; Kurath, Dean E.; Adkins, Harold E.; Billing, Justin M.; Burns, Carolyn A.; Davis, James M.; Enderlin, Carl W.; Fischer, Christopher M.; Jenks, Jeromy WJ; Lukins, Craig D.; MacFarlan, Paul J.; Shutthanandan, Janani I.; Smith, Dennese M.

    2012-12-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  20. Leak detection capability in CANDU reactors

    Energy Technology Data Exchange (ETDEWEB)

    Azer, N.; Barber, D.H.; Boucher, P.J. [and others

    1997-04-01

    This paper addresses the moisture leak detection capability of Ontario Hydro CANDU reactors which has been demonstrated by performing tests on the reactor. The tests confirmed the response of the annulus gas system (AGS) to the presence of moisture injected to simulate a pressure tube leak and also confirmed the dew point response assumed in leak before break assessments. The tests were performed on Bruce A Unit 4 by injecting known and controlled rates of heavy water vapor. To avoid condensation during test conditions, the amount of moisture which could be injected was small (2-3.5 g/hr). The test response demonstrated that the AGS is capable of detecting and annunciating small leaks. Thus confidence is provided that it would alarm for a growing pressure tube leak where the leak rate is expected to increase to kg/hr rapidly. The measured dew point response was close to that predicted by analysis.

  1. Leak detection capability in CANDU reactors

    International Nuclear Information System (INIS)

    Azer, N.; Barber, D.H.; Boucher, P.J.

    1997-01-01

    This paper addresses the moisture leak detection capability of Ontario Hydro CANDU reactors which has been demonstrated by performing tests on the reactor. The tests confirmed the response of the annulus gas system (AGS) to the presence of moisture injected to simulate a pressure tube leak and also confirmed the dew point response assumed in leak before break assessments. The tests were performed on Bruce A Unit 4 by injecting known and controlled rates of heavy water vapor. To avoid condensation during test conditions, the amount of moisture which could be injected was small (2-3.5 g/hr). The test response demonstrated that the AGS is capable of detecting and annunciating small leaks. Thus confidence is provided that it would alarm for a growing pressure tube leak where the leak rate is expected to increase to kg/hr rapidly. The measured dew point response was close to that predicted by analysis

  2. Stability of extemporaneously prepared preservative-free prochlorperazine nasal spray.

    Science.gov (United States)

    Yellepeddi, Venkata K

    2018-01-01

    The stability of an extemporaneously prepared preservative-free prochlorperazine 5-mg/mL nasal spray was evaluated. The preservative-free prochlorperazine nasal spray was prepared by adding 250 mg of prochlorperazine edisylate to 50 mL of citrate buffer in a low-density polyethylene nasal spray bottle. A stability-indicating high-performance liquid chromatography (HPLC) method was developed and validated using the major degradant prochlorperazine sulfoxide and by performing forced-degradation studies. For chemical stability studies, 3 100-μL samples of the preservative-free prochlorperazine from 5 nasal spray bottles stored at room temperature were collected at days 0, 20, 30, 45, and 60 and were assayed in triplicate using the stability-indicating HPLC method. Microbiological testing involved antimicrobial effectiveness testing based on United States Pharmacopeia ( USP ) chapter 51 and quantitative microbiological enumeration of aerobic bacteria, yeasts, and mold based on USP chapter 61. Samples for microbiological testing were collected at days 0, 30, and 60. The stability-indicating HPLC method clearly identified the degradation product prochlorperazine sulfoxide without interference from prochlorperazine. All tested solutions retained over 90% of the initial prochlorperazine concentration for the 60-day study period. There were no detectable changes in color, pH, and viscosity in any sample. There was no growth of bacteria, yeast, and mold for 60 days in all samples tested. An extemporaneously prepared preservative-free nasal spray solution of prochlorperazine edisylate 5 mg/mL was physically, chemically, and microbiologically stable for 60 days when stored at room temperature in low-density polyethylene bottles. Copyright © 2018 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  3. High quality ceramic coatings sprayed by high efficiency hypersonic plasma spraying gun

    International Nuclear Information System (INIS)

    Zhu Sheng; Xu Binshi; Yao JiuKun

    2005-01-01

    This paper introduced the structure of the high efficiency hypersonic plasma spraying gun and the effects of hypersonic plasma jet on the sprayed particles. The optimised spraying process parameters for several ceramic powders such as Al 2 O 3 , Cr 2 O 3 , ZrO 2 , Cr 3 C 2 and Co-WC were listed. The properties and microstructure of the sprayed ceramic coatings were investigated. Nano Al 2 O 3 -TiO 2 ceramic coating sprayed by using the high efficiency hypersonic plasma spraying was also studied. Compared with the conventional air plasma spraying, high efficiency hypersonic plasma spraying improves greatly the ceramic coatings quality but at low cost. (orig.)

  4. Effect of Laser Remelting on Friction-Wear Behaviors of Cold Sprayed Al Coatings in 3.5% NaCl Solution

    Directory of Open Access Journals (Sweden)

    Zhang Jing

    2018-02-01

    Full Text Available A cold sprayed Al coating on S355 structural steel was processed using a laser remelting (LR. The surface and cross-section morphologies, chemical compositions, and phases of as-obtained Al coating before and after LR were analyzed using a scanning electronic microscope (SEM, energy dispersive spectrometer (EDS, and X-ray diffractometer (XRD, respectively, and their hardness was measured using a micro-hardness tester. The friction-wear behaviors of Al coating before and after LR in 3.5% NaCl solution were conducted to simulate the sand and gravel scouring on its surface in seawater, the effects of wear loads and speeds on the tribological properties of Al coating were analyzed, and the wear mechanisms under different wear loads and speeds were also discussed. The results show that the Al coating after LR is primarily composed of an Al phase and its hardness is 104.66 HV, increasing 54.70 HV than the cold sprayed Al coating. The average coefficient of friction (COF of cold sprayed Al coating at the wear load of 0.5, 1.0 and 1.5 N is 0.285, 0.239, and 0.435, respectively, while that after LR is 0.243, 0.227, and 0.327, respectively, decreased by 14.73%, 5.02% and 24.83% compared to the cold sprayed Al coating. The wear rate of cold sprayed Al coating at the wear load of 0.5, 1.0 and 1.5 N is 1.60 × 10−4, 2.36 × 10−4, and 2.40 × 10−4 mm3/m·N, respectively, while that after LR is 1.59 × 10−4, 1.70 × 10−4, and 1.94 × 10–4 mm3/m·N, respectively, decreased by 1%, 32%, and 23%, respectively, indicating that LR has high anti-friction performance. Under the wear load action of 1.0 N, the average COF of laser remelted Al coating at the wear speeds of 300, 400 and 500 times/min is 0.294, 0.279, and 0.239, respectively, and the corresponding wear rate is 1.06 × 10−4, 1.24 × 10−4, and 1.70 × 10−4 mm3/m·N, respectively. The wear mechanism of cold sprayed Al coating is primarily corrosion wear at the loads of 0.5 and 1.0 N, and

  5. 40 CFR 86.328-79 - Leak checks.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Leak checks. 86.328-79 Section 86.328... Gasoline-Fueled and Diesel-Fueled Heavy-Duty Engines; Gaseous Exhaust Test Procedures § 86.328-79 Leak checks. (a) Vacuum side leak check. (1) Any location within the analysis system where a vacuum leak could...

  6. Effect of spray angle and spray volume on deposition of a medium droplet spray with air support in ivy pot plants.

    Science.gov (United States)

    Foqué, Dieter; Pieters, Jan G; Nuyttens, David

    2014-03-01

    Spray boom systems, an alternative to the predominantly-used spray guns, have the potential to considerably improve crop protection management in glasshouses. Based on earlier experiments, the further optimization of the deposits of a medium spray quality extended range flat fan nozzle type using easy adjustable spray boom settings was examined. Using mineral chelate tracers and water sensitive papers, the spray results were monitored at three plant levels, on the upper side and the underside of the leaves, and on some off-target collectors. In addition, the deposition datasets of all tree experiments were compared. The data showed that the most efficient spray distribution with the medium spray quality flat fan nozzles was found with a 30° forward angled spray combined with air support and an application rate of 1000 L ha(-1) . This technique resulted in a more uniform deposition in the dense canopy and increased spray deposition on the lower side of the leaves compared with the a standard spray boom application. Applying 1000 L ha(-1) in two subsequent runs instead of one did not seem to show any added value. Spray deposition can be improved hugely simply by changing some spray boom settings like nozzle type, angling the spray, using air support and adjusting the spray volume to the crop. © 2013 Society of Chemical Industry.

  7. Formation of hydrotalcite coating on the aluminum alloy 6060 in spray system

    DEFF Research Database (Denmark)

    Zhou, Lingli; Friis, Henrik; Roefzaad, Melanie

    2016-01-01

    Coatings with the composition of Li-Al-NO3 hydrotalcite were formed on the Al alloy 6060 using a spray system. The coatings consist of crystals with a typical hydrotalcite structure. Dense, uniform and blade-like flakes cover completely the surface of the Al substrate. The coatings display a multi......-layer structure with average thickness of ∼1000 nm. The hydrotalcite-coated samples performed better than those without coatings in salt-spray and filiform-corrosion tests, and further treatment involving sealing with a Mg acetate solution and dipping in a H2O2 + Ce-based solution improved the corrosion...

  8. High-T/sub c/ oxide superconductors prepared by spray-drying method

    International Nuclear Information System (INIS)

    Nakamura, N.; Nakano, T.; Goth, S.; Shimotomai, M.

    1988-01-01

    A spray-drying method has been worked out to prepare the superconducting oxide YBa/sub 2/Cu/sub 3/O/sub x/ by using aqueous solution of acetates of the component metals. Spray-dried powders have shown to be very reactive and full calcination has been easily attained at 900 0 C for 12 hrs. The density of the ceramics sintered at 950 0 C for 12 hrs has reached a value of 98% of the theoretical density. The resistivity of the spray-dry processed sample is 150μΩ-cm at the onset temperature and the residual resistivity extrapolated to O K is almost zero. It is also found that degradation of the superconducting state by application of magnetic field is much improved for the spray-dry processed samples

  9. In vitro fatigue behaviour of vacuum plasma and detonation gun sprayed hydroxyapatite coatings.

    Science.gov (United States)

    Gledhill, H C; Turner, I G; Doyle, C

    2001-06-01

    The fatigue behaviour of vacuum plasma sprayed (VPS) and detonation gun sprayed (DGUN) hydroxyapatite coatings on titanium substrates has been compared in air and in buffered Ringer's solution. There was an increase in the surface microcracking and bulk porosity of both types of coating tested in air. After 1 million cycles in Ringer's solution the VPS coatings had completely delaminated from their substrates. In contrast the DGUN coatings retained their integrity when tested up to 10 million cycles but were beginning to show signs of delamination at the interface.

  10. Optical fuel spray measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hillamo, H.

    2011-07-01

    Diesel fuel sprays, including fuel/air mixing and the physics of two-phase jet formation, are discussed in the thesis. The fuel/air mixing strongly affects emissions formation in spray combustion processes where the local combustion conditions dictate the emission formation. This study comprises optical measurements both in pressurized spray test rigs and in a running engine.The studied fuel injection was arranged with a common rail injection system and the injectors were operated with a solenoid-based injection valve. Both marine and heavy-duty diesel engine injectors were used in the study. Optical fuel spray measurements were carried out with a laser-based double-framing camera system. This kind of equipments is usually used for flow field measurements with Particle Image Velocimetry technique (PIV) as well as for backlight imaging. Fundamental fuel spray properties and spray formation were studied in spray test rigs. These measurements involved studies of mixing, atomization, and the flow field. Test rig measurements were used to study the effect of individual injection parameters and component designs. Measurements of the fuel spray flow field, spray penetration, spray tip velocity, spray angle, spray structure, droplet accumulation, and droplet size estimates are shown. Measurement campaign in a running optically accessible large-bore medium-speed engine was also carried out. The results from engine tests were compared with equivalent test rig measurements, as well as computational results, to evaluate the level of understanding of sprays. It was shown that transient spray has an acceleration and a deceleration phase. Successive flow field measurements (PIV) in optically dense diesel spray resulted in local and average velocity data of diesel sprays. Processing fuel spray generates a flow field to surrounding gas and entrainment of surrounding gas into fuel jet was also seen at the sides of the spray. Laser sheet imaging revealed the inner structure of diesel

  11. Special storage of leaking fuel at Paks NPP

    International Nuclear Information System (INIS)

    Biro, Janos; Szőke, L.; Burján, T.; Lukács, R.; Hózer, H.

    2015-01-01

    In this paper the activities related with spent, hermetic as well as leaking fuel handling and storage, including: Spent fuel pool; Transportation criteria for the spent fuel assemblies and Interim spent fuel dry storage; Short-term storage in the spent fuel pool; Identification of the leaking assemblies by the TS-device; Present conception of Identification, handling of the leaking FAs; Modified transport procedure for the leaking FAs; Calculation of solved activity inside the leaking fuel rod; Solved activity limit values for the leaking FAs; Long-term storage in the interim spent Fuel dry storage are presented. At the end authors’ concluded that: 1) The leaking FA can be transported to the interim dry storage together with the other spent fuel assemblies in the transport container. 2) The transport-documentation of the leaking FA has to contain: isotope inventory, calculated solved activity values of the failed FA and the quantity of failed fuel rods. 3) Performing three leakage tests of the identified leaking FA before the transportation in the 5FP. it is useful to decrease the solved activity concentration inside the leaking FA and give additional information about the extent of the leakage. 4) We can calculate simply the solved activity of the leaking FA. 5) The modified transport procedure will have to be authorized. 6) The radiological effects of the leaking FA are negligible relative to the natural background radiation

  12. Low Level Leaks

    Science.gov (United States)

    1998-01-01

    NASA has transferred the improved portable leak detector technology to UE Systems, Inc.. This instrument was developed to detect leaks in fluid systems of critical launch and ground support equipment. This system incorporates innovative electronic circuitry, improved transducers, collecting horns, and contact sensors that provide a much higher degree of reliability, sensitivity and versatility over previously used systems. Potential commercial uses are pipelines, underground utilities, air-conditioning systems, petrochemical systems, aerospace, power transmission lines and medical devices.

  13. Influence of Surface Pretreatment on the Corrosion Resistance of Cold-Sprayed Nickel Coatings in Acidic Chloride Solution

    Science.gov (United States)

    Scendo, Mieczyslaw; Zorawski, Wojciech; Staszewska-Samson, Katarzyna; Makrenek, Medard; Goral, Anna

    2018-03-01

    Corrosion resistance of the cold-sprayed nickel coatings deposited on the Ni surface (substrate) without and with abrasive grit-blasting treatment of the substrate was investigated. The corundum powder with different grain sizes was used. The corrosive environment contained an acidic chloride solution. The mechanism of the corrosion of nickel was suggested and discussed. Corrosion electrochemical parameters were determined by electrochemical methods. The corrosion effect of a nickel coating depends on the grain size used to prepare the substrate. The nickel coating after the medium grit-blasting treatment of the substrate was found to be the most corrosion resistant. However, the smallest resistance on the corrosion effect should be attributed to the nickel coating on the substrate after the coarse grit-blasting treatment.

  14. Spray characteristics and spray cooling heat transfer in the non-boiling regime

    International Nuclear Information System (INIS)

    Cheng, Wen-Long; Han, Feng-Yun; Liu, Qi-Nie; Fan, Han-Lin

    2011-01-01

    Spray cooling is an effective method for dissipating high heat fluxes in the field of electronics thermal control. In this study, experiments were performed with distilled water as a test liquid to study the spray cooling heat transfer in non-boiling regime. A Phase Doppler Anemometry (PDA) was used to study the spray characteristics. The effects of spray flow rate, spray height, and inlet temperature on spray cooling heat transfer were investigated. It was found that the parameters affect heat transfer of spray cooling in non-boiling regime by the spray characteristics and working fluid thermophysical properties. Then the corresponding droplet axial velocity and Sauter mean diameter (SMD) were successfully correlated with mean absolute error of 15%, which were based upon the orifice diameter, the Weber and Reynolds numbers of the orifice flow prior to liquid breakup, dimensionless spray height and spray cross-section radius. The heat transfer in non-boiling regime was correlated with a mean absolute error of 7%, which was mainly associated with the working fluid thermophysical properties, the Weber and Reynolds numbers hitting the heating surface, dimensionless heating surface temperature and diameter. -- Highlights: → The spray flow rate, spray height, and inlet temperature affect heat transfer of spray cooling in non-boiling regime by the spray characteristics and the working fluid thermophysical properties. → Then the corresponding droplet axial velocity and Sauer mean diameter (SMD) were successfully correlated with mean absolute error of 15%. → The heat transfer in non-boiling regime was correlated with a mean absolute error of 7%.

  15. Pipeline leak detection using volatile tracers

    International Nuclear Information System (INIS)

    Thompson, G.M.; Golding, R.D.

    1993-01-01

    A method of leak detection for underground storage tanks and pipelines adds volatile tracers to the products in the tanks and analyzes the surrounding shallow soil gases for tracer vapors. This method has several advantages: the success of the test is not limited by the size and structural design of the vessels, tanks can be tested at any fill level without taking the tank out of service, the location of a leak along a pipeline is clearly marked by the location of the tracer, and liquid leaks as small as 0.2 liters per hour (lph) can be detected. A limitation is: the backfill material must have some degree of air permeability in the zone above the water table. Several field tests document the success achieved using this method. A tracer leak detection system was installed at Homestead AFB after several other testing methods failed to locate a leak at a valve pit location along approximately 4 kilometers of fuel transfer piping. The leak was detected to the side of the valve pit at a depth of approximately 2.5 meters below the ground surface. Another installation of Edwards AFB involved the collection of 415 soil gas samples along approximately 3,050 meters of 15.25-centimeter fiberglass pipeline. Fourteen separate leaks were detected

  16. Lanthanide-based laser-induced phosphorescence for spray diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Voort, D. D. van der, E-mail: d.d.v.d.voort@tue.nl; Water, W. van de; Kunnen, R. P. J.; Clercx, H. J. H.; Heijst, G. J. F. van [Applied Physics Department, Eindhoven University of Technology, 5612 AZ Eindhoven (Netherlands); Maes, N. C. J.; Sweep, A. M.; Dam, N. J. [Mechanical Engineering Department, Eindhoven University of Technology, 5612 AZ Eindhoven (Netherlands); Lamberts, T. [Institute of Theoretical Chemistry, University of Stuttgart, D-70569 Stuttgart (Germany)

    2016-03-15

    Laser-induced phosphorescence (LIP) is a relatively recent and versatile development for studying flow dynamics. This work investigates certain lanthanide-based molecular complexes for their use in LIP for high-speed sprays. Lanthanide complexes in solutions have been shown to possess long phosphorescence lifetimes (∼1-2 ms) and to emit light in the visible wavelength range. In particular, europium and terbium complexes are investigated using fluorescence/phosphorescence spectrometry, showing that europium-thenoyltrifluoracetone-trioctylphosphineoxide (Eu-TTA-TOPO) can be easily and efficiently excited using a standard frequency-tripled Nd:YAG laser. The emitted spectrum, with maximum intensity at a wavelength of 614 nm, is shown not to vary strongly with temperature (293-383 K). The decay constant of the phosphorescence, while independent of ambient pressure, decreases by approximately 12 μs/K between 323 and 373 K, with the base level of the decay constant dependent on the used solvent. The complex does not luminesce in the gas or solid state, meaning only the liquid phase is visualized, even in an evaporating spray. By using an internally excited spray containing the phosphorescent complex, the effect of vaporization is shown through the decrease in measured intensity over the length of the spray, together with droplet size measurements using interferometric particle imaging. This study shows that LIP, using the Eu-TTA-TOPO complex, can be used with different solvents, including diesel surrogates. Furthermore, it can be easily handled and used in sprays to investigate spray breakup and evaporation.

  17. Experiments and calculations to leak openings and leak rates on typical piping components and systems

    International Nuclear Information System (INIS)

    Hoefler, A.; Grebner, H.

    1992-01-01

    Calculations of leak opening and leak rate for through cracks in piping components have been performed. The analyses are pre- or mostly post-calculations to experiments performed at the HDR facility under PWR operating conditions. Piping components under consideration are small diameter straight pipes with circumferential cracks, pipe bends with longitudinal or circumferential cracks and pipe branches with weldment cracks. The component are loaded by internal pressure and opening as well as closing bending moment. The finite element method and two-phase flow leak rate programs are used for the calculations. Results of the analyses are presented as J-integral values, crack opening displacements and areas and leak rates as well as comparisons to the experimental results. 6 refs., 16 figs., 2 tabs

  18. Leak detection for underground storage tanks

    International Nuclear Information System (INIS)

    Durgin, P.B.; Young, T.M.

    1993-01-01

    This symposium was held in New Orleans, Louisiana on January 29, 1992. The purpose of this conference was to provide a forum for exchange of state-of-the-art information on leak detection for underground storage tanks that leaked fuel. A widespread concern was protection of groundwater supplies from these leaking tanks. In some cases, the papers report on research that was conducted two or three years ago but has never been adequately directed to the underground storage tank leak-detection audience. In other cases, the papers report on the latest leak-detection research. The symposium was divided into four sessions that were entitled: Internal Monitoring; External Monitoring; Regulations and Standards; and Site and Risk Evaluation. Individual papers have been cataloged separately for inclusion in the appropriate data bases

  19. Stimulated leaks found with SmartBall tool

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-05-15

    Pure Technologies has developed a SmartBall leak detection tool which can be used in oil and gas pipelines. This tool contains acoustic sensors which listen for leaks and other problems in pipelines. Pig tracking units are used to track the tool along with receivers positioned on the pipe. With these technologies, SmartBall is able to detect small leaks that conventional methods would not detect and to assess their location accurately. Two runs on a Petrobras pipeline in Brazil highlighted the effectiveness of this technology, detecting three simulated leaks as small as 240mL/min. In addition, this system can give an estimation of the leak rate and traverse non piggable pipelines. Software is then used to analyze data and generate a report giving the size and location of the leaks identified. SmartBall is a technology capable of detecting small leaks and locating them in all sorts of oil and gas pipelines.

  20. Leak detector for reactor pressure vessel

    International Nuclear Information System (INIS)

    Morimoto, Mikio.

    1991-01-01

    A branched pipe is disposed to a leak off pipeline led from a flange surface which connects the main body and the upper lid of a reactor pressure vessel. An exhaust pump is disposed to the branched pipe and a moisture gage is disposed on the side of the exhaustion and a dry air supplier is connected to the branched pipe. Upon conducting a pressure-proof leak test for the reactor pressure vessel, the exhaust pump is operated and an electromagnet valve disposed at the upstream of the dry air supplier is opened and closed repeatedly. The humidity of air sucked by the exhaust pump is detected by the moisture gage. If leaks should be caused in the joining surface of the flange, leaked water is diffused as steams. Accordingly, occurrence of leak can be detected instantly based on the comparison with the moisture level of the dry air as a standard. In this way, a leak test can be conducted reliably in a short period of time with no change of for the reactor pressure container itself. (I.N.)

  1. Rust Contamination from Water Leaks in the Cosmic Dust Lab and Lunar and Meteorite Thin Sections Labs at Johnson Space Center

    Science.gov (United States)

    Kent, J. J.; Berger, E. L.; Fries, M. D.; Bastien, R.; McCubbin, F. M.; Pace, L.; Righter, K.; Sutter, B.; Zeigler, R. A.; Zolensky, M.

    2017-01-01

    On the early morning of September 15th, 2016, on the first floor of Building 31 at NASA-Johnson Space Center, the hose from a water chiller ruptured and began spraying water onto the floor. The water had been circulating though old metal pipes, and the leaked water contained rust-colored particulates. The water flooded much of the western wing of the building's ground floor before the leak was stopped, and it left behind a residue of rust across the floor, most notably in the Apollo and Meteorite Thin Section Labs and Sample Preparation Lab. No samples were damaged in the event, and the affected facilities are in the process of remediation. At the beginning of 2016, a separate leak occurred in the Cosmic Dust Lab, located in the same building. In that lab, a water leak occurred at the bottom of the sink used to clean the lab's tools and containers with ultra-pure water. Over years of use, the ultra-pure water eroded the metal sink piping and leaked water onto the inside of the lab's flow bench. This water also left behind a film of rusty material. The material was cleaned up and the metal piping was replaced with PVC pipe and sealed with Teflon plumber's tape. Samples of the rust detritus were collected from both incidents. These samples were imaged and analyzed to determine their chemical and mineralogical compositions. The purpose of these analyses is to document the nature of the detritus for future reference in the unlikely event that these materials occur as contaminants in the Cosmic Dust samples or Apollo or Meteorite thin sections.

  2. Layered growth with bottom-spray granulation for spray deposition of drug.

    Science.gov (United States)

    Er, Dawn Z L; Liew, Celine V; Heng, Paul W S

    2009-07-30

    The gap in scientific knowledge on bottom-spray fluidized bed granulation has emphasized the need for more studies in this area. This paper comparatively studied the applicability of a modified bottom-spray process and the conventional top-spray process for the spray deposition of a micronized drug during granulation. The differences in circulation pattern, mode of growth and resultant granule properties between the two processes were highlighted. The more ordered and consistent circulation pattern of particles in a bottom-spray fluidized bed was observed to give rise to layered granule growth. This resulted in better drug content uniformity among the granule batches and within a granule batch. The processes' sensitivities to wetting and feed material characteristics were also compared and found to differ markedly. Less robustness to differing process conditions was observed for the top-spray process. The resultant bottom-spray granules formed were observed to be less porous, more spherical and had good flow properties. The bottom-spray technique can thus be potentially applied for the spray deposition of drug during granulation and was observed to be a good alternative to the conventional technique for preparing granules.

  3. Spray deposition and spray drift in orchard spraying by multiple row sprayers

    NARCIS (Netherlands)

    Wenneker, M.; Zande, van de J.C.; Michielsen, J.G.P.; Stallinga, H.; Velde, van P.

    2016-01-01

    The evaluation of the latest data on spray drift in orchard spraying in the Netherlands, and measurements of surface water quality parameters show that the current legislation and measures are insufficient to protect the surface water. To meet the national and European objectives regarding surface

  4. The experiment and analysis on small leak phenomena

    International Nuclear Information System (INIS)

    Jeong, Kyung Chai; Hwang, S. T.; Kim, B. H.; Jeong, J. Y.

    2000-07-01

    The liquid sodium which is used as a coolant in LMFBR, may give rise to a serious trouble in the safety aspect of steam generator. The defects in a heat transfer tube, such as pin-hole or tube welding defect, will result in a leakage of high pressure steam into the sodium side and production of hydrogen gas and corrosive sodium compounds which can cause significant damage to the tube wall of steam generator by using exothermic reaction. In significant damage to the tube wall of steam generator by using exothermic reaction. In this case, initial leak size will be enlarged with time and the leak rate developed to large leak through the micro, small, intermediate leaks. Therefore, the analysis of sodium-water reaction phenomena on the micro and small water leaks in the heat transfer tube is very important in the initial leak stage in the aspects of the protection of leak progress and safety evaluation of steam generator. In this study, firstly, the micro and small leaks phenomena, such as reopen size, shape, and time of leak path, self-wastage, corrosion of tube materials, was analyzed from the literature survey and water leakage experiments using the leak specimen. In small water leak experiments, the leak path was plugged by the sodium-water reaction products at the leak path of a specimen, and re-open phenomena were not observed in initial experiments. Other leak experiments, reopen phenomena of self-plugged leak path was observed. Re-open mechanism of sealed path could be explained by the thermal transient and vibration of heat transfer tube. As a result, perfect reopen time of self plugged leak path was observed to be about 130 minutes after water leak initiation. Reopen shape of a specimen was appeared with double layer of circular type, and reopen size of this specimen surface was about 2 mm diameter on sodium side. Also, the corrosion of a specimen initiated from sodium side, the segregation phenomena of Cr in the specimen was found much more than those of

  5. Differentially pumped spray deposition as a rapid screening tool for organic and perovskite solar cells

    Science.gov (United States)

    Jung, Yen-Sook; Hwang, Kyeongil; Scholes, Fiona H.; Watkins, Scott E.; Kim, Dong-Yu; Vak, Doojin

    2016-01-01

    We report a spray deposition technique as a screening tool for solution processed solar cells. A dual-feed spray nozzle is introduced to deposit donor and acceptor materials separately and to form blended films on substrates in situ. Using a differential pump system with a motorised spray nozzle, the effect of film thickness, solution flow rates and the blend ratio of donor and acceptor materials on device performance can be found in a single experiment. Using this method, polymer solar cells based on poly(3-hexylthiophene) (P3HT):(6,6)-phenyl C61 butyric acid methyl ester (PC61BM) are fabricated with numerous combinations of thicknesses and blend ratios. Results obtained from this technique show that the optimum ratio of materials is consistent with previously reported values confirming this technique is a very useful and effective screening method. This high throughput screening method is also used in a single-feed configuration. In the single-feed mode, methylammonium iodide solution is deposited on lead iodide films to create a photoactive layer of perovskite solar cells. Devices featuring a perovskite layer fabricated by this spray process demonstrated a power conversion efficiencies of up to 7.9%. PMID:26853266

  6. Differentially pumped spray deposition as a rapid screening tool for organic and perovskite solar cells.

    Science.gov (United States)

    Jung, Yen-Sook; Hwang, Kyeongil; Scholes, Fiona H; Watkins, Scott E; Kim, Dong-Yu; Vak, Doojin

    2016-02-08

    We report a spray deposition technique as a screening tool for solution processed solar cells. A dual-feed spray nozzle is introduced to deposit donor and acceptor materials separately and to form blended films on substrates in situ. Using a differential pump system with a motorised spray nozzle, the effect of film thickness, solution flow rates and the blend ratio of donor and acceptor materials on device performance can be found in a single experiment. Using this method, polymer solar cells based on poly(3-hexylthiophene) (P3HT):(6,6)-phenyl C61 butyric acid methyl ester (PC61BM) are fabricated with numerous combinations of thicknesses and blend ratios. Results obtained from this technique show that the optimum ratio of materials is consistent with previously reported values confirming this technique is a very useful and effective screening method. This high throughput screening method is also used in a single-feed configuration. In the single-feed mode, methylammonium iodide solution is deposited on lead iodide films to create a photoactive layer of perovskite solar cells. Devices featuring a perovskite layer fabricated by this spray process demonstrated a power conversion efficiencies of up to 7.9%.

  7. Leak testing and repair of fusion devices

    International Nuclear Information System (INIS)

    Kozman, T.A.

    1983-01-01

    The leak testing, reporting and vacuum leak repair techniques of the MFTF yin-yang number one magnet system, the world's largest superconducting magnet system, are discussed. Based on this experience, techniques will be developed for testing and repairing leaks on the 42 MFTF-B magnets. The leak-hunting techniques for the yin-yang magnet systems were applied to two helium circuits (the coil bundle and guard vacuum; both require helium flow for magnet cooldown), their associated piping, liquid nitrogen radiation shields, and piping. Additionally, during MFTF-B operation there will be warm water plasma shields and piping that require leak checking

  8. Demonstration of a Solution Film Leak Test Technique and Equipment for the S00645 Canister Closure

    International Nuclear Information System (INIS)

    Cannell, G.R.

    1999-01-01

    The purpose of this effort was to demonstrate that the SFT technique, when adapted to a DWPF canister nozzle, is capable of detecting leaks not meeting the Waste Acceptance Product Specifications (WAPS) acceptance criterion

  9. Preparation of polymer-blended quinine nanocomposite particles by spray drying and assessment of their instrumental bitterness-masking effect using a taste sensor.

    Science.gov (United States)

    Taki, Moeko; Tagami, Tatsuaki; Ozeki, Tetsuya

    2017-05-01

    The development of taste-masking technologies for foods and drugs is essential because it would enable people to consume and receive healthy and therapeutic effect without distress. In the current study, in order to develop a novel method to prepare nanocomposite particles (microparticles containing bitter nanoparticles) in only one step, by using spray drying, a two-solution mixing nozzle-equipped spray dryer that we previously reported was used. The nanocomposite particles with or without poorly water-soluble polymers prepared using our spray-drying technique were characterized. (1) The organic solution containing quinine, a model of bitter compound and poorly water-soluble polymers and (2) sugar alcohol (mannitol) aqueous solution were separately flown in tubes and two solutions were spray dried through two-solution type spray nozzle to prepare polymer-blended quinine nanocomposite particles. Mean diameters of nanoparticles, taste-masking effect and dissolution rate of quinine were evaluated. The results of taste masking by taste sensor suggested that the polymer (Eudragit EPO, Eudragit S100 or Ethyl cellulose)-blended quinine nanocomposite particles exhibited marked masking of instrumental quinine bitterness compared with the quinine nanocomposite particles alone. Quinine nanocomposite formulations altered the quinine dissolution rate, indicating that they can control intestinal absorption of quinine. These results suggest that polymer-blended quinine composite particles prepared using our spray-drying technique are useful for masking bitter tastes in the field of food and pharmaceutical industry.

  10. Effect of spray application technique on spray deposition in greenhouse strawberries and tomatoes.

    Science.gov (United States)

    Braekman, Pascal; Foque, Dieter; Messens, Winy; Van Labeke, Marie-Christine; Pieters, Jan G; Nuyttens, David

    2010-02-01

    Increasingly, Flemish greenhouse growers are using spray booms instead of spray guns to apply plant protection products. Although the advantages of spray booms are well known, growers still have many questions concerning nozzle choice and settings. Spray deposition using a vertical spray boom in tomatoes and strawberries was compared with reference spray equipment. Five different settings of nozzle type, size and pressure were tested with the spray boom. In general, the standard vertical spray boom performed better than the reference spray equipment in strawberries (spray gun) and in tomatoes (air-assisted sprayer). Nozzle type and settings significantly affected spray deposition and crop penetration. Highest overall deposits in strawberries were achieved using air-inclusion or extended-range nozzles. In tomatoes, the extended-range nozzles and the twin air-inclusion nozzles performed best. Using smaller-size extended-range nozzles above the recommended pressure range resulted in lower deposits, especially inside the crop canopy. The use of a vertical spray boom is a promising technique for applying plant protection products in a safe and efficient way in tomatoes and strawberries, and nozzle choice and setting should be carefully considered.

  11. Spray-coatable negative photoresist for high topography MEMS applications

    International Nuclear Information System (INIS)

    Arnold, Markus; Haas, Sven; Schwenzer, Falk; Schwenzer, Gunther; Reuter, Danny; Geßner, Thomas; Voigt, Anja; Gruetzner, Gabi

    2017-01-01

    In microsystem technology, the lithographical processing of substrates with a topography is very important. Interconnecting lines, which are routed over sloped topography sidewalls from the top of the protecting wafer to the contact pads of the device wafer, are one example of patterning over a topography. For structuring such circuit paths, a photolithography process, and therefore a process for homogeneous photoresist coating, is required. The most flexible and advantageous way of depositing a homogeneous photoresist film over structures with high topography steps is spray-coating. As a pattern transfer process for circuit paths in cavities, the lift-off process is widely used. A negative resist, like ma-N (MRT) or AZnLOF (AZ) is favoured for lift-off processes due to the existing negative angle of the sidewalls. Only a few sprayable negative photoresists are commercially available. In this paper, the development of a novel negative resist spray-coating based on a commercially available single-layer lift-off resist for spin-coating, especially for the patterning of structures inside the cavity and on the cavity wall, is presented. A variety of parameters influences the spray-coating process, and therefore the patterning results. Besides the spray-coating tool and the parameters, the composition of the resist solution itself also influences the coating results. For homogeneous resist coverage over the topography of the substrate, different solvent combinations for diluting the resist solution, different chuck temperatures during the coating process, and also the softbake conditions, are all investigated. The solvent formulations and the process conditions are optimized with respect to the homogeneity of the resist coverage on the top edge of the cavities. Finally, the developed spray-coating process, the resist material and the process stability are demonstrated by the following applications: (i) lift-off, (ii) electroplating, (iii) the wet and (iv) the dry

  12. Application of acoustic leak detection technology for the detection and location of leaks in light water reactors

    International Nuclear Information System (INIS)

    Kupperman, D.S.; Prine, D.; Mathieson, T.

    1988-10-01

    This report presents the results of a study to evaluate the adequacy of leak detection systems in light water reactors. The sources of numerous reported leaks and methods of detection have been documented. Research to advance the state of the art of acoustic leak detection is presented, and procedures for implementation are discussed. 14 refs., 70 figs., 10 tabs

  13. Investigation of adsorption properties of alumina produced by vacuum spray method

    International Nuclear Information System (INIS)

    Khrustaleva, K; Voronova, G

    2016-01-01

    In this paper nanopowders obtained by vacuum spray method were studied. The phase composition of the obtained powders is γ - Al 2 O 3 . Obtained nanopowders have specific surface area about 200 m 2 /g. Adsorptive properties of these powders were studied by static adsorption from solutions. The anionic dye eosin was selected as adsorbate. It has been found that the powders obtained by vacuum spray method have significant capacity to adsorb eosin. (paper)

  14. Inorganic photovoltaic devices fabricated using nanocrystal spray deposition.

    Science.gov (United States)

    Foos, Edward E; Yoon, Woojun; Lumb, Matthew P; Tischler, Joseph G; Townsend, Troy K

    2013-09-25

    Soluble inorganic nanocrystals offer a potential route to the fabrication of all-inorganic devices using solution deposition techniques. Spray processing offers several advantages over the more common spin- and dip-coating procedures, including reduced material loss during fabrication, higher sample throughput, and deposition over a larger area. The primary difference observed, however, is an overall increase in the film roughness. In an attempt to quantify the impact of this morphology change on the devices, we compare the overall performance of spray-deposited versus spin-coated CdTe-based Schottky junction solar cells and model their dark current-voltage characteristics. Spray deposition of the active layer results in a power conversion efficiency of 2.3 ± 0.3% with a fill factor of 45.7 ± 3.4%, Voc of 0.39 ± 0.06 V, and Jsc of 13.3 ± 3.0 mA/cm(2) under one sun illumination.

  15. Ultrasonic Detectors Safely Identify Dangerous, Costly Leaks

    Science.gov (United States)

    2013-01-01

    In 1990, NASA grounded its space shuttle fleet. The reason: leaks detected in the hydrogen fuel systems of the Space Shuttles Atlantis and Columbia. Unless the sources of the leaks could be identified and fixed, the shuttles would not be safe to fly. To help locate the existing leaks and check for others, Kennedy Space Center engineers used portable ultrasonic detectors to scan the fuel systems. As a gas or liquid escapes from a leak, the resulting turbulence creates ultrasonic noise, explains Gary Mohr, president of Elmsford, New York-based UE Systems Inc., a long-time leader in ultrasonic detector technologies. "In lay terms, the leak is like a dog whistle, and the detector is like the dog ear." Because the ultrasound emissions from a leak are highly localized, they can be used not only to identify the presence of a leak but also to help pinpoint a leak s location. The NASA engineers employed UE s detectors to examine the shuttle fuel tanks and solid rocket boosters, but encountered difficulty with the devices limited range-certain areas of the shuttle proved difficult or unsafe to scan up close. To remedy the problem, the engineers created a long-range attachment for the detectors, similar to "a zoom lens on a camera," Mohr says. "If you are on the ground, and the leak is 50 feet away, the detector would now give you the same impression as if you were only 25 feet away." The enhancement also had the effect of reducing background noise, allowing for a clearer, more precise detection of a leak s location.

  16. Higher Temperature Thermal Barrier Coatings with the Combined Use of Yttrium Aluminum Garnet and the Solution Precursor Plasma Spray Process

    Science.gov (United States)

    Gell, Maurice; Wang, Jiwen; Kumar, Rishi; Roth, Jeffery; Jiang, Chen; Jordan, Eric H.

    2018-04-01

    Gas-turbine engines are widely used in transportation, energy and defense industries. The increasing demand for more efficient gas turbines requires higher turbine operating temperatures. For more than 40 years, yttria-stabilized zirconia (YSZ) has been the dominant thermal barrier coating (TBC) due to its outstanding material properties. However, the practical use of YSZ-based TBCs is limited to approximately 1200 °C. Developing new, higher temperature TBCs has proven challenging to satisfy the multiple property requirements of a durable TBC. In this study, an advanced TBC has been developed by using the solution precursor plasma spray (SPPS) process that generates unique engineered microstructures with the higher temperature yttrium aluminum garnet (YAG) to produce a TBC that can meet and exceed the major performance standards of state-of-the-art air plasma sprayed YSZ, including: phase stability, sintering resistance, CMAS resistance, thermal cycle durability, thermal conductivity and erosion resistance. The temperature improvement for hot section gas turbine materials (superalloys & TBCs) has been at the rate of about 50 °C per decade over the last 50 years. In contrast, SPPS YAG TBCs offer the near-term potential of a > 200 °C improvement in temperature capability.

  17. Higher Temperature Thermal Barrier Coatings with the Combined Use of Yttrium Aluminum Garnet and the Solution Precursor Plasma Spray Process

    Science.gov (United States)

    Gell, Maurice; Wang, Jiwen; Kumar, Rishi; Roth, Jeffery; Jiang, Chen; Jordan, Eric H.

    2018-02-01

    Gas-turbine engines are widely used in transportation, energy and defense industries. The increasing demand for more efficient gas turbines requires higher turbine operating temperatures. For more than 40 years, yttria-stabilized zirconia (YSZ) has been the dominant thermal barrier coating (TBC) due to its outstanding material properties. However, the practical use of YSZ-based TBCs is limited to approximately 1200 °C. Developing new, higher temperature TBCs has proven challenging to satisfy the multiple property requirements of a durable TBC. In this study, an advanced TBC has been developed by using the solution precursor plasma spray (SPPS) process that generates unique engineered microstructures with the higher temperature yttrium aluminum garnet (YAG) to produce a TBC that can meet and exceed the major performance standards of state-of-the-art air plasma sprayed YSZ, including: phase stability, sintering resistance, CMAS resistance, thermal cycle durability, thermal conductivity and erosion resistance. The temperature improvement for hot section gas turbine materials (superalloys & TBCs) has been at the rate of about 50 °C per decade over the last 50 years. In contrast, SPPS YAG TBCs offer the near-term potential of a > 200 °C improvement in temperature capability.

  18. Performance evaluation of PFBR wire type sodium leak detectors

    International Nuclear Information System (INIS)

    Vijayakumar, G.; Rajan, K.K.; Nashine, B.K.; Chandramouli, S.; Madhusoodanan, K.; Kalyanasundaram, P.

    2011-01-01

    Highlights: → Performance evaluation of wire type leak detectors was conducted in LEENA facility by creating sodium leaks. → The lowest leak rate of 214 g/h was detected in 50 min and the highest detection time was 6 h for a leak rate of 222 g/h. → Factors affecting the leak detection time are packing density of thermal insulation, layout of heater, temperature, etc. → Relationship between leak rate and detection time was established and a leak rate of 100 g/h is likely to be detected in 11.1 h. → Contact resistance of leaked sodium increased to 3.5 kilo ohms in 20 h. - Abstract: Wire type leak detectors working on conductivity principle are used for detecting sodium leak in the secondary sodium circuits of fast breeder reactors. It is required to assess the performance of these detectors and confirm that they are meeting the requirements. A test facility by name LEENA was constructed at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam to test the wire type leak detector lay out by simulating different sodium leak rates. This test facility consists of a sodium dump tank, a test vessel, interconnecting pipelines with valves, micro filter and test section with leak simulators. There are three different test sections in the test set up of length 1000 mm each. These test sections simulate piping of Prototype Fast Breeder Reactor (PFBR) secondary circuit and the wire type leak detector layout in full scale. All test sections are provided with leak simulators. A leak simulator consists of a hole of size one mm drilled in the test section and closed with a tapered pin. The tapered pin position in the hole is adjusted by a screw mechanism and there by the annular gap of flow area is varied for getting different leak rates. Various experiments were conducted to evaluate the performance of the leak detectors by creating different sodium leak rates. This paper deals with the details of wire type leak detector layout for the secondary sodium circuit of

  19. Vacuum leak test technique of JT-60

    International Nuclear Information System (INIS)

    Kaminaga, Atsushi; Arai, Takashi; Kodama, Kozo; Sasaki, Noboru; Saidoh, Masahiro

    1998-01-01

    Since a vacuum vessel of JT-60 is very large (167 m 3 ) and is combined with many components, such as magnetic coils, neutral beam injection systems and RF heating systems, etc., the position of leak testing exceeds 700. The two kind of techniques for vacuum leak test used in JT-60 has been described. Firstly the probe helium gas can be fed remotely in the three-dimensionally sectioned 54 regions of the JT-60 torus. The leak test was very rapidly performed by using this method. Secondly the helium detector system has been modified by the additional installation of the cryopump, which reduced the background level of the deuterium gas. The sensitivity of vacuum leak test with the cryopump was two orders of magnitude larger than that of without it. The examples of the performed vacuum leak test are stated. The vacuum leaks during experiments were 9 times. They were caused by thermal strain and plasma discharge. The vacuum leaks just after maintenance are 36 times which mainly caused by mis-installation. (author)

  20. Acoustic leak detection of LMFBR steam generator

    International Nuclear Information System (INIS)

    Kumagai, Hiromichi; Yoshida, Kazuo

    1993-01-01

    The development of a water leak detector with short response time for LMFBR steam generators is required to prevent the failure propagation caused by the sodium-water reaction and to maintain structural safety in steam generators. The development of an acoustic leak detector assuring short response time has attracted. The purpose of this paper is to confirm the basic detection feasibility of the active acoustic leak detector, and to investigate the leak detection method by erasing the background noise by spectrum analysis of the passive acoustic leak detector. From a comparison of the leak detection sensitivity of the active and the passive method, the active method is not influenced remarkably by the background noise, and it has possibility to detect microleakage with short response time. We anticipate a practical application of the active method in the future. (author)

  1. Evaluation of advanced and current leak detection systems

    International Nuclear Information System (INIS)

    Kupperman, D.S.

    1988-01-01

    U.S. Nuclear Regulatory Commission Guide 1.45 recommends the use of at least three different detection methods in reactors to detect leakage. Monitoring of both sump-flow and airborne particulate radioactivity is mandatory. A third method can involve either monitoring of condensate flow rate from air coolers or monitoring of airborne gaseous radioactivity. Although the methods currently used for leak detection reflect the state of the art, other techniques may be developed and used. Since the recommendations of Regulatory Guide 1.45 are not mandatory, Licensee Event Report Compilations have been reviewed to help establish actual capabilities for leak detection. The review of event reports, which had previously covered the period of June 1985 to August 1986 has been extended, and now covers events to June 1987. The total number of significant events is now 83. These reports have provided documented, sometimes detailed, summaries of reactor leaks. They have helped establish the capabilities of existing systems to detect and locate leaks. Differences between PWRs and BWRs with regard to leak detection have now been analyzed. With regard to detection methods, the greatest differences between reactor types are as follows: (a) The sump pump is reported as the detection method more frequently in BWRs than in PWRs (64% vs. 35%). (b) The radiation monitor is reported as the detection method (excluding false alarms) more frequently in PWRs. Current efforts at Argonne National Laboratory (ANL) to evaluate advanced acoustic leak detection methods are directed toward the generation and analysis of acoustic data from large (0.5 to 10 gal/min) leaks and modification of the software of the GARD/ANL advanced acoustic leak detection system. In order to reach the goal of 10 gal/min leaks, the Steam Generator Test Facility at ANL has been modified to carry out the leak testing. Tests were carried out with water at 525 deg. F and 1100 psi leaking through a fatigue crack in a 4-in

  2. Evaluation of pipeline leak detection systems

    International Nuclear Information System (INIS)

    Glauz, W.D.; Flora, J.D.; Hennon, G.J.

    1993-01-01

    Leaking underground storage tank system presents an environmental concern and a potential health hazard. It is well known that leaks in the piping associated with these systems account for a sizeable fraction of the leaks. EPA has established performance standards for pipeline leak detection systems, and published a document presenting test protocols for evaluating these systems against the standards. This paper discusses a number of facets and important features of evaluating such systems, and presents results from tests of several systems. The importance of temperature differences between the ground and the product in the line is shown both in theory and with test data. The impact of the amount of soil moisture present is addressed, along with the effect of frozen soil. These features are addressed both for line tightness test systems, which must detect leaks of 0.10 gal/h (0.38 L/h) at 150% of normal line pressure, or 0.20 gal/h (0.76 L/h) at normal line pressure, and for automatic line leak detectors that must detect leaks of 3 gal/h (11 L/h) at 10 psi (69 kPa) within an hour of the occurrence of the leak. This paper also addresses some statistical aspects of the evaluation of these systems. Reasons for keeping the evaluation process ''blind'' to the evaluated company are given, along with methods for assuring that the tests are blind. Most importantly, a test procedure is presented for evaluating systems that report a flow rate (not just a pass/fail decision) that is much more efficient than the procedure presented in the EPA protocol, and is just as stringent

  3. Assessment of differences between products obtained in conventional and vacuum spray dryer

    Directory of Open Access Journals (Sweden)

    Fernanda de Melo RAMOS

    Full Text Available Abstract In this work, an experimental unit of a vacuum spray dryer was built. This prototype attempted to combine the advantages of freeze-drying (drying at low temperatures due to vacuum and spray drying (increase of surface area aiming the improvement of heat transfer efficiency. Maltodextrin solutions were dried in the vacuum operated equipment and in conventional spray dryer. The vacuum spray dryer system allowed obtaining powder at low temperatures due to the lowering of pressure conditions (2-5 kPa inside the drying chamber. The products obtained in the two systems were characterized and compared for particle size distribution, moisture content, water activity, bulk density and solubility in water. The processes yields were also evaluated and compared. The vacuum spray dryer system allowed the production of larger, more soluble and less dense particles than those obtained in the conventional configuration of the equipment, resulting in drier and, therefore, with lower water activity particles. Thus, the use of the vacuum spray dryer as a drying technique may be an alternative for the production of powder rich in thermosensitive compounds.

  4. Microstructure evolution during spray rolling and heat treatment of 2124 Al

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, K.M. [Industrial Technology Department, Idaho National Laboratory, Idaho Falls, ID 83415-2050 (United States)], E-mail: kevin.mchugh@inl.gov; Lin, Y.; Zhou, Y.; Johnson, S.B.; Delplanque, J.-P.; Lavernia, E.J. [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States)

    2008-03-25

    Spray rolling is a strip-casting technology that combines elements of spray forming and twin-roll casting. It consists of atomizing molten metal with a high velocity inert gas, quenching the resultant droplets in flight, and directing the spray between mill rolls. In-flight convection heat transfer from atomized droplets and conduction heat transfer at the rolls rapidly remove the metal's latent heat. Hot deformation of the semi-solid material in the rolls results in fully consolidated, rapidly-solidified strip. Spray rolling operates at a higher solidification rate than conventional twin-roll casting and is able to process a broader range of alloys at high production rates. A laboratory-scale strip caster was constructed and used to evaluate the interplay of processing parameters and strip quality for strips up to 200 mm wide and 1.6-6.4 mm thick. This paper examines microstructure evolution during spray rolling and explores how gas-to-metal mass flow ratio influences the microstructure and mechanical properties of spray-rolled 2124 Al. The influences of solution heat treatment and cold rolling on grain structure and constituent particle spheroidization are also examined.

  5. Indoor spray measurement of spray drift potential using a spray drift test bench : effect of drift-reducing nozzle types, spray boom height, nozzle spacing and forward speed

    NARCIS (Netherlands)

    Moreno Ruiz, J.R.

    2014-01-01

    In a series of indoor experiments spray drift potential was assessed when spraying over a spray drift testbench with two different driving speeds, 2m/s and 4m/s, two different spray boom heights, 30 cm and 50 cm, and two different nozzle spacing, 25 cm and 50 cm, for six different nozzle types. The

  6. Helium leak testing methods in nuclear applications

    International Nuclear Information System (INIS)

    Ahmad, Anis

    2004-01-01

    Helium mass-spectrometer leak test is the most sensitive leak test method. It gives very reliable and sensitive test results. In last few years application of helium leak testing has gained more importance due to increased public awareness of safety and environment pollution caused by number of growing chemical and other such industries. Helium leak testing is carried out and specified in most of the critical area applications like nuclear, space, chemical and petrochemical industries

  7. Nitrite spray treatment to promote red color stability of vacuum packaged beef.

    Science.gov (United States)

    Song, Xiao; Cornforth, Daren; Whittier, Dick; Luo, Xin

    2015-01-01

    Sodium nitrite solutions were sprayed on select grade boneless rib (M. longissimus thoracis) and bottom round (mainly M. biceps femoris) steaks individually, to form bright red nitric oxide myoglobin (NO-Mb) in vacuum packages. Our objective was to determine the optimum level of nitrite in spray for stable raw steak redness, low or no residual nitrite, and low surface pinking (ham-like cured color) after cooking. Results showed that steaks sprayed with 100-350 ppm nitrite solutions had 3.0-3.6g weight gain and a calculated level of 1.3-5.3mg nitrite added/kg steak, but very low (color during 21 days of storage at 1°C (a*>10; chroma C*>16). Raw steak redness was less stable in round than rib. Visual scores for pinkness after cooking were low, indicating that cooked color at even the highest nitrite treatment (350 ppm) was acceptable. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Automated Leak Detection Of Buried Tanks Using Geophysical Methods At The Hanford Nuclear Site

    International Nuclear Information System (INIS)

    Calendine, S.; Schofield, J.S.; Levitt, M.T.; Fink, J.B.; Rucker, D.F.

    2011-01-01

    At the Hanford Nuclear Site in Washington State, the Department of Energy oversees the containment, treatment, and retrieval of liquid high-level radioactive waste. Much of the waste is stored in single-shelled tanks (SSTs) built between 1943 and 1964. Currently, the waste is being retrieved from the SSTs and transferred into newer double-shelled tanks (DSTs) for temporary storage before final treatment. Monitoring the tanks during the retrieval process is critical to identifying leaks. An electrically-based geophysics monitoring program for leak detection and monitoring (LDM) has been successfully deployed on several SSTs at the Hanford site since 2004. The monitoring program takes advantage of changes in contact resistance that will occur when conductive tank liquid leaks into the soil. During monitoring, electrical current is transmitted on a number of different electrode types (e.g., steel cased wells and surface electrodes) while voltages are measured on all other electrodes, including the tanks. Data acquisition hardware and software allow for continuous real-time monitoring of the received voltages and the leak assessment is conducted through a time-series data analysis. The specific hardware and software combination creates a highly sensitive method of leak detection, complementing existing drywell logging as a means to detect and quantify leaks. Working in an industrial environment such as the Hanford site presents many challenges for electrical monitoring: cathodic protection, grounded electrical infrastructure, lightning strikes, diurnal and seasonal temperature trends, and precipitation, all of which create a complex environment for leak detection. In this discussion we present examples of challenges and solutions to working in the tank farms of the Hanford site.

  9. Leak detection using structure-borne noise

    Science.gov (United States)

    Holland, Stephen D. (Inventor); Chimenti, Dale E. (Inventor); Roberts, Ronald A. (Inventor)

    2010-01-01

    A method for detection and location of air leaks in a pressure vessel, such as a spacecraft, includes sensing structure-borne ultrasound waveforms associated with turbulence caused by a leak from a plurality of sensors and cross correlating the waveforms to determine existence and location of the leak. Different configurations of sensors and corresponding methods can be used. An apparatus for performing the methods is also provided.

  10. Physicochemical and in vitro deposition properties of salbutamol sulphate/ipratropium bromide and salbutamol sulphate/excipient spray dried mixtures for use in dry powder inhalers.

    Science.gov (United States)

    Corrigan, Deirdre O; Corrigan, Owen I; Healy, Anne Marie

    2006-09-28

    The physicochemical and aerodynamic properties of spray dried powders of the drug/drug mixture salbutamol sulphate/ipratropium bromide were investigated. The in vitro deposition properties of spray dried salbutamol sulphate and the spray dried drug/excipient mixtures salbutamol sulphate/lactose and salbutamol sulphate/PEG were also determined. Spray drying ipratropium bromide monohydrate resulted in a crystalline material from both aqueous and ethanolic solution. The product spray dried from aqueous solution consisted mainly of ipratropium bromide anhydrous. There was evidence of the presence of another polymorphic form of ipratropium bromide. When spray dried from ethanolic solution the physicochemical characterisation suggested the presence of an ipratropium bromide solvate with some anhydrous ipratropium bromide. Co-spray drying salbutamol sulphate with ipratropium bromide resulted in amorphous composites, regardless of solvent used. Particles were spherical and of a size suitable for inhalation. Twin impinger studies showed an increase in the fine particle fraction (FPF) of spray dried salbutamol sulphate compared to micronised salbutamol sulphate. Co-spray dried salbutamol sulphate:ipratropium bromide 10:1 and 5:1 systems also showed an increase in FPF compared to micronised salbutamol sulphate. Most co-spray dried salbutamol sulphate/excipient systems investigated demonstrated FPFs greater than that of micronised drug alone. The exceptions to this were systems containing PEG 4000 20% or PEG 20,000 40% both of which had FPFs not significantly different from micronised salbutamol sulphate. These two systems were crystalline unlike most of the other spray dried composites examined which were amorphous in nature.

  11. SEALING SIMULATED LEAKS

    Energy Technology Data Exchange (ETDEWEB)

    Michael A. Romano

    2004-09-01

    This report details the testing equipment, procedures and results performed under Task 7.2 Sealing Simulated Leaks. In terms of our ability to seal leaks identified in the technical topical report, Analysis of Current Field Data, we were 100% successful. In regards to maintaining seal integrity after pigging operations we achieved varying degrees of success. Internal Corrosion defects proved to be the most resistant to the effects of pigging while External Corrosion proved to be the least resistant. Overall, with limitations, pressure activated sealant technology would be a viable option under the right circumstances.

  12. Characterization of Ni-YSZ anodes for solid oxide fuel cells fabricated by solution precursor plasma spraying with axial feedstock injection

    Science.gov (United States)

    Metcalfe, Craig; Lay-Grindler, Elisa; Kesler, Olivera

    2014-02-01

    Nickel and yttria-stabilized zirconia (YSZ) anodes were fabricated by solution precursor plasma spraying (SPPS) and incorporated into metal-supported solid oxide fuel cells (SOFC). A power density of 0.45 W cm-2 at 0.7 V and a peak power density of 0.52 W cm-2 at 750 °C in humidified H2 was obtained, which are the first performance results reported for an SOFC having an anode fabricated by SPPS. The effects of solution composition, plasma gas composition, and stand-off distance on the composition of the deposited Ni-YSZ coatings by SPPS were evaluated. It was found that the addition of citric acid to the aqueous solution delayed re-solidification of NiO particles, improving the deposition efficiency and coating adhesion. The composition of the deposited coatings was found to vary with torch power. Increasing torch power led to coatings with decreasing Ni content, as a result of Ni vaporizing in-flight at stand-off distances less than 60 mm from the torch nozzle exit.

  13. Basis UST leak detection systems

    International Nuclear Information System (INIS)

    Silveria, V.

    1992-01-01

    This paper reports that gasoline and other petroleum products are leaking from underground storage tanks (USTs) at an alarming rate, seeping into soil and groundwater. Buried pipes are an even greater culprit, accounting for most suspected and detected leaks according to Environmental Protection Agency (EPA) estimates. In response to this problem, the EPA issued regulations setting standards for preventing, detecting, reporting, and cleaning up leaks, as well as fiscal responsibility. However, federal regulations are only a minimum; some states have cracked down even harder Plant managers and engineers have a big job ahead of them. The EPA estimates that there are more than 75,000 fuel USTs at US industrial facilities. When considering leak detection systems, the person responsible for making the decision has five primary choices: inventory reconciliation combined with regular precision tightness tests; automatic tank gauging; groundwater monitoring; interstitial monitoring of double containment systems; and vapor monitoring

  14. The influence of spray properties on intranasal deposition.

    Science.gov (United States)

    Foo, Mow Yee; Cheng, Yung-Sung; Su, Wei-Chung; Donovan, Maureen D

    2007-01-01

    While numerous devices, formulations, and spray characteristics have been shown to influence nasal deposition efficiency, few studies have attempted to identify which of these interacting factors plays the greatest role in nasal spray deposition. The deposition patterns of solutions with a wide range of surface tensions and viscosities were measured using an MRI-derived nasal cavity replica. The resulting spray plumes had angles between 29 degrees and 80 degrees and contained droplet sizes (D(v50)) from 37-157 microm. Each formulation contained rhodamine 590 as a fluorescent marker for detection. Administration angles of 30 degrees , 40 degrees , or 50 degrees above horizontal were tested to investigate the role of user technique on nasal deposition. The amount of spray deposited within specific regions of the nasal cavity was determined by disassembling the replica and measuring the amount of rhodamine retained in each section. Most of the spray droplets were deposited onto the anterior region of the model, but sprays with small plume angles were capable of reaching the turbinate region with deposition efficiencies approaching 90%. Minimal dependence on droplet size, viscosity, or device was observed. Changes in inspiratory flow rate (0-60 L/min) had no significant effect on turbinate deposition efficiency. Both plume angle and administration angle were found to be important factors in determining deposition efficiency. For administration angles of 40 degrees or 50 degrees , maximal turbinate deposition efficiency (30-50%) occurred with plume angles of 55-65 degrees , whereas a 30 degrees administration angle gave an approximately 75% deposition efficiency for similar plume angles. Deposition efficiencies of approximately 90% could be achieved with plume angles deposition efficiency, while many other spray parameters, including particle size, have relatively minor influences on deposition within the nasal cavity.

  15. Air-Leak Effects on Ear-Canal Acoustic Absorbance

    Science.gov (United States)

    Rasetshwane, Daniel M.; Kopun, Judy G.; Gorga, Michael P.; Neely, Stephen T.

    2015-01-01

    Objective: Accurate ear-canal acoustic measurements, such as wideband acoustic admittance, absorbance, and otoacoustic emissions, require that the measurement probe be tightly sealed in the ear canal. Air leaks can compromise the validity of the measurements, interfere with calibrations, and increase variability. There are no established procedures for determining the presence of air leaks or criteria for what size leak would affect the accuracy of ear-canal acoustic measurements. The purpose of this study was to determine ways to quantify the effects of air leaks and to develop objective criteria to detect their presence. Design: Air leaks were simulated by modifying the foam tips that are used with the measurement probe through insertion of thin plastic tubing. To analyze the effect of air leaks, acoustic measurements were taken with both modified and unmodified foam tips in brass-tube cavities and human ear canals. Measurements were initially made in cavities to determine the range of critical leaks. Subsequently, data were collected in ears of 21 adults with normal hearing and normal middle-ear function. Four acoustic metrics were used for predicting the presence of air leaks and for quantifying these leaks: (1) low-frequency admittance phase (averaged over 0.1–0.2 kHz), (2) low-frequency absorbance, (3) the ratio of compliance volume to physical volume (CV/PV), and (4) the air-leak resonance frequency. The outcome variable in this analysis was the absorbance change (Δabsorbance), which was calculated in eight frequency bands. Results: The trends were similar for both the brass cavities and the ear canals. ΔAbsorbance generally increased with air-leak size and was largest for the lower frequency bands (0.1–0.2 and 0.2–0.5 kHz). Air-leak effects were observed in frequencies up to 10 kHz, but their effects above 1 kHz were unpredictable. These high-frequency air leaks were larger in brass cavities than in ear canals. Each of the four predictor variables

  16. Spray cooling

    International Nuclear Information System (INIS)

    Rollin, Philippe.

    1975-01-01

    Spray cooling - using water spraying in air - is surveyed as a possible system for make-up (peak clipping in open circuit) or major cooling (in closed circuit) of the cooling water of the condensers in thermal power plants. Indications are given on the experiments made in France and the systems recently developed in USA, questions relating to performance, cost and environmental effects of spray devices are then dealt with [fr

  17. Aerospace Payloads Leak Test Methodology

    Science.gov (United States)

    Lvovsky, Oleg; Grayson, Cynthia M.

    2010-01-01

    Pressurized and sealed aerospace payloads can leak on orbit. When dealing with toxic or hazardous materials, requirements for fluid and gas leakage rates have to be properly established, and most importantly, reliably verified using the best Nondestructive Test (NDT) method available. Such verification can be implemented through application of various leak test methods that will be the subject of this paper, with a purpose to show what approach to payload leakage rate requirement verification is taken by the National Aeronautics and Space Administration (NASA). The scope of this paper will be mostly a detailed description of 14 leak test methods recommended.

  18. Spray boom for selectively spraying a herbicidal composition onto dicots

    DEFF Research Database (Denmark)

    2012-01-01

    There is provided a method and spray boom for discriminating cereal crop (monocot) and weeds (dicots). The spray boom includes means for digitally recording an image of a selected area to be treated by a nozzle on the spray boom, whereby a plant material is identified based on a segmentation proc...

  19. 49 CFR 195.444 - CPM leak detection.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false CPM leak detection. 195.444 Section 195.444... PIPELINE Operation and Maintenance § 195.444 CPM leak detection. Each computational pipeline monitoring (CPM) leak detection system installed on a hazardous liquid pipeline transporting liquid in single...

  20. Photoluminescence of spray pyrolysis deposited ZnO nanorods

    Directory of Open Access Journals (Sweden)

    Mikli Valdek

    2011-01-01

    Full Text Available Abstract Photoluminescence of highly structured ZnO layers comprising well-shaped hexagonal rods is presented. The ZnO rods (length 500-1,000 nm, diameter 100-300 nm were grown in air onto a preheated soda-lime glass (SGL or ITO/SGL substrate by low-cost chemical spray pyrolysis method using zinc chloride precursor solutions and growth temperatures in the range of 450-550°C. We report the effect of the variation in deposition parameters (substrate type, growth temperature, spray rate, solvent type on the photoluminescence properties of the spray-deposited ZnO nanorods. A dominant near band edge (NBE emission is observed at 300 K and at 10 K. High-resolution photoluminescence measurements at 10 K reveal fine structure of the NBE band with the dominant peaks related to the bound exciton transitions. It is found that all studied technological parameters affect the excitonic photoluminescence in ZnO nanorods. PACS: 78.55.Et, 81.15.Rs, 61.46.Km

  1. Lack of a synergistic effect of arginine-glutamic acid on the physical stability of spray-dried bovine serum albumin.

    Science.gov (United States)

    Reslan, Mouhamad; Demir, Yusuf K; Trout, Bernhardt L; Chan, Hak-Kim; Kayser, Veysel

    2017-09-01

    Improving the physical stability of spray-dried proteins is essential for enabling pulmonary delivery of biotherapeutics as a noninvasive alternative to injections. Recently, a novel combination of two amino acids - l-arginine (l-Arg) and l-glutamic acid (l-Glu), has been reported to have synergistic protein-stabilizing effects on various protein solutions. Using spray-dried bovine serum albumin (BSA) reconstituted in solution as a model protein, we investigated the synergistic effect of these amino acids on the physical stability of proteins. Five BSA solutions were prepared: (1) BSA with no amino acids (control); (2) with 50 mM l-Arg; (3) with 200 mM l-Arg, (4) with 50 mM l-Glu and (5) with 25:25 mM of Arg:Glu. All solutions were spray-dried and accelerated studies at high temperatures were performed. Following accelerated studies, monomer BSA loss was measured using SE-HPLC. We found that l-Arg significantly improved the physical stability of spray-dried BSA even at low concentrations, however, when combined with l-Glu, was ineffective at reducing monomer BSA loss. Our findings demonstrate the limitations in using Arg-Glu for the stabilization of spray-dried BSA. Furthermore, we found that a low concentration of l-Glu enhanced monomer BSA loss. These findings may have significant implications on the design of future biotherapeutic formulations.

  2. Reduction of spray pressure leads to less emission and better deposition of spray liquid at high-volume spraying in greenhouse tomato

    NARCIS (Netherlands)

    Os, van E.A.; Michielsen, J.M.G.P.; Corver, F.J.M.; Berg, van den J.V.; Bruins, M.A.; Porskamp, H.A.J.; Zande, van de J.C.

    2005-01-01

    In an experimental greenhouse, growing a tomato crop, it was investigated if a reduction in spray pressure could improve the spray result, while, simultaneously, emission to the ground could be reduced. Spray deposition on the leaves and the emission to the ground was evaluated at different spray

  3. 40 CFR 63.1434 - Equipment leak provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Equipment leak provisions. 63.1434... Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63.1434 Equipment leak provisions. (a) The owner or operator of each affected source shall comply with the HON equipment leak...

  4. 49 CFR 195.134 - CPM leak detection.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false CPM leak detection. 195.134 Section 195.134... PIPELINE Design Requirements § 195.134 CPM leak detection. This section applies to each hazardous liquid... computational pipeline monitoring (CPM) leak detection system and each replaced component of an existing CPM...

  5. Concentration device for leak liquids

    International Nuclear Information System (INIS)

    Matsumoto, Kaname; Matsuda, Ken; Takabori, Ken-ichi.

    1987-01-01

    Purpose: To improve radioactivity recovery and volume-reducing rates, as well as enable safety and easy handling for leak liquids resulted from reptures in coolant circuits. Constitution: The device of the invention comprises an evaporation vessel filled with leak fluids to a predetermined level, an airtight vessel disposed in the evaporation vessel containing hydrophilic porous material partially immersed in the leak fluids and means for heating the hydrophilic material. In this device, leak liquids are absorbed in the hydrophilic porous material, a great amount of water is evaporated from the outer surface of the hydrophilic porous material exposed above the liquid surface, and salts and radioactive material are remained on the inside and the outer surface of the porous material. The evaporated water content is condensated and recovered in a cooler and the remaining salts, etc. are discarded together with the porous material. The volume-reducing property can be improved by constituting the porous material with burnable material. (Takahashi, M.)

  6. Fully automatic AI-based leak detection system

    Energy Technology Data Exchange (ETDEWEB)

    Tylman, Wojciech; Kolczynski, Jakub [Dept. of Microelectronics and Computer Science, Technical University of Lodz in Poland, ul. Wolczanska 221/223, Lodz (Poland); Anders, George J. [Kinectrics Inc., 800 Kipling Ave., Toronto, Ontario M8Z 6C4 (Canada)

    2010-09-15

    This paper presents a fully automatic system intended to detect leaks of dielectric fluid in underground high-pressure, fluid-filled (HPFF) cables. The system combines a number of artificial intelligence (AI) and data processing techniques to achieve high detection capabilities for various rates of leaks, including leaks as small as 15 l per hour. The system achieves this level of precision mainly thanks to a novel auto-tuning procedure, enabling learning of the Bayesian network - the decision-making component of the system - using simulated leaks of various rates. Significant new developments extending the capabilities of the original leak detection system described in and form the basis of this paper. Tests conducted on the real-life HPFF cable system in New York City are also discussed. (author)

  7. Small-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2013-05-29

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and

  8. Small-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2012-11-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  9. Transient leak detection in crude oil pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Beushausen, R.; Tornow, S.; Borchers, H. [Nord-West Oelleitung, Wilhelmshaven (Germany); Murphy, K.; Zhang, J. [Atmos International Ltd., Manchester (United Kingdom)

    2004-07-01

    Nord-West Oelleitung (NWO) operates 2 crude oil pipelines from Wilhemshaven to Koln and Hamburg respectively. German regulations for transporting flammable substances stipulate that 2 independent continuously working procedures be used to detect leaks. Leak detection pigs are used routinely to complement the surveillance system. This paper described the specific issues of transient leak detection in crude oil pipelines. It was noted that traditional methods have failed to detect leaks that occur immediately after pumps are turned on or off because the pressure wave generated by the transient dominates the pressure wave that results from the leak. Frequent operational changes in a pipeline are often accompanied by an increased number of false alarms and failure to detect leaks due to unsteady operations. NWO therefore decided to have the Atmos statistical pipeline leak detection (SPLD) system installed on their pipelines. The key to the SPLD system is the sequential probability ratio test. Comprehensive data validation is performed following reception of pipeline data from the supervisory control and data acquisition (SCADA) system. The validated data is then used to calculate the corrected flow imbalance, which is fed into the SPRT to determine if there is an increase in the flow imbalance. Pattern recognition is then used to distinguish a leak from operational changes. The SPLD is unique because it uses 3 computational pipeline monitoring methods simultaneously, namely modified volume balance, statistical analysis, and pressure and flow monitoring. The successful installation and testing of the SPLD in 2 crude oil pipelines was described along with the main difficulties associated with transient leaks. Field results were presented for both steady-state and transient conditions. 5 refs., 2 tabs., 16 figs.

  10. Fuel leak testing performance at NPP Jaslovske Bohunice

    International Nuclear Information System (INIS)

    Slugen, V.; Krnac, S.; Smiesko, I.

    1995-01-01

    The NPP Bohunice VVER-440 fuel leak testing experience are relatively extensive in comparison with other VVER-440 users. As the first Europe NPP was adapted Siemens (KWU) in core-sipping equipment to VVER-440 units and since this time were have done these tests also for NPP Paks (Hungary) and NPP Dukovany (Czech Republic). The occurrence of leaking fuel assemblies in NPP is in the last 5 years relatively stabilised and low. A significant difference can be observed between type V-230 (31 leaks) and type V-213 (1 leak). None of of the indicated leaking fuel assemblies has been investigated in the hot cell. Therefore cannot be confirm the effective causes of leak occurrence. Nevertheless, the fuel failure rate and the performance of leak testing in NPP Bohunice are comparable to the world standard at PWR's. 1 tab., 2 figs., 3 refs

  11. Fuel leak testing performance at NPP Jaslovske Bohunice

    Energy Technology Data Exchange (ETDEWEB)

    Slugen, V; Krnac, S [Slovak Technical Univ., Bratislava (Slovakia); Smiesko, I [Nuclear Powr Plant EBO, Jaslovske Bohuce (Slovakia)

    1996-12-31

    The NPP Bohunice VVER-440 fuel leak testing experience are relatively extensive in comparison with other VVER-440 users. As the first Europe NPP was adapted Siemens (KWU) in core-sipping equipment to VVER-440 units and since this time were have done these tests also for NPP Paks (Hungary) and NPP Dukovany (Czech Republic). The occurrence of leaking fuel assemblies in NPP is in the last 5 years relatively stabilised and low. A significant difference can be observed between type V-230 (31 leaks) and type V-213 (1 leak). None of of the indicated leaking fuel assemblies has been investigated in the hot cell. Therefore cannot be confirm the effective causes of leak occurrence. Nevertheless, the fuel failure rate and the performance of leak testing in NPP Bohunice are comparable to the world standard at PWR`s. 1 tab., 2 figs., 3 refs.

  12. In situ spray deposition of cell-loaded, thermally and chemically gelling hydrogel coatings for tissue regeneration.

    Science.gov (United States)

    Pehlivaner Kara, Meryem O; Ekenseair, Adam K

    2016-10-01

    In this study, the efficacy of creating cellular hydrogel coatings on warm tissue surfaces through the minimally invasive, sprayable delivery of thermoresponsive liquid solutions was investigated. Poly(N-isopropylacrylamide)-based (pNiPAAm) thermogelling macromers with or without addition of crosslinking polyamidoamine (PAMAM) macromers were synthesized and used to produce in situ forming thermally and chemically gelling hydrogel systems. The effect of solution and process parameters on hydrogel physical properties and morphology was evaluated and compared to poly(ethylene glycol) and injection controls. Smooth, fast, and conformal hydrogel coatings were obtained when pNiPAAm thermogelling macromers were sprayed with high PAMAM concentration at low pressure. Cellular hydrogel coatings were further fabricated by different spraying techniques: single-stream, layer-by-layer, and dual stream methods. The impact of spray technique, solution formulation, pressure, and spray solution viscosity on the viability of fibroblast and osteoblast cells encapsulated in hydrogels was elucidated. In particular, the early formation of chemically crosslinked micronetworks during bulk liquid flow was shown to significantly affect cell viability under turbulent conditions compared to injectable controls. The results demonstrated that sprayable, in situ forming hydrogels capable of delivering cell populations in a homogeneous therapeutic coating on diseased tissue surfaces offer promise as novel therapies for applications in regenerative medicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2383-2393, 2016. © 2016 Wiley Periodicals, Inc.

  13. Influence of nature of the substrate in the deposition of yttria-stabilized zirconia by spray pyrolysis

    International Nuclear Information System (INIS)

    Halmenschlager, C.M.; Malfatti, C.F.; Bergmann, C.P.; Neagu, R.

    2012-01-01

    Spray pyrolysis technique consist in spraying a precursor solution on a heated substrate. In the last few decades this process has attracted much attention because of its versatility. Controlling the parameters is possible to produce dense or porous film. Spray pyrolysis has been applied to obtain several materials such as electrodes or electrolytes for SOFC, semiconductors, materials for solar cells and so on. However, some behaviors such as Leidenfrost effect have been poorly considered and it may affect the coating quality. This work aims to evaluate the influence of the substrate and how Leidenfrost effect affects the coating by spray pyrolysis. To achieve this goal yttria-stabilized zirconia solutions made with different solvents were deposited on different substrates at different temperatures. These coatings were characterized by X-ray diffraction and scanning electron microscopy. The results show that there is a limit temperature which is related to properties of the solvent and the surface of the substrates where films are continuous. (author)

  14. 40 CFR 63.648 - Equipment leak standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Equipment leak standards. 63.648...) National Emission Standards for Hazardous Air Pollutants From Petroleum Refineries § 63.648 Equipment leak...) through (c)(10) and (e) through (i) of this section. (1) The instrument readings that define a leak for...

  15. 40 CFR 63.769 - Equipment leak standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Equipment leak standards. 63.769... § 63.769 Equipment leak standards. (a) This section applies to equipment subject to this subpart and... release to detect leaks, except under the following conditions. (i) The owner or operator has obtained...

  16. 40 CFR 63.1331 - Equipment leak provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Equipment leak provisions. 63.1331... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1331 Equipment leak... in pumps and agitator seals in light liquid service shall not be considered to be a leak. For...

  17. 40 CFR 63.1410 - Equipment leak provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Equipment leak provisions. 63.1410... leak provisions. The owner or operator of each affected source shall comply with the requirements of 40 CFR part 63, subpart UU (national emission standards for equipment leaks (control level 2)) for all...

  18. Device provides controlled gas leaks

    Science.gov (United States)

    Kami, S. K.; King, H. J.

    1968-01-01

    Modified palladium leak device provides a controlled release /leak/ of very small quantities of gas at low or medium pressures. It has no moving parts, requires less than 5 watts to operate, and is capable of releasing the gas either continuously or in pulses at adjustable flow rates.

  19. Modulation of leak K(+) channel in hypoglossal motoneurons of rats by serotonin and/or variation of pH value.

    Science.gov (United States)

    Xu, Xue-Feng; Tsai, Hao-Jan; Li, Lin; Chen, Yi-Fan; Zhang, Cheng; Wang, Guang-Fa

    2009-08-25

    The cloned TWIK-related acid-sensitive K(+) channel (TASK-1) is sensitive to the pH changes within physiological pH range (pK~7.4). Recently, the native TASK-1-like channel was suggested to be the main contributor to the background (or leak) K(+) conductance in the motoneurons of the brain stem. Serotonin (5-HT) and variation of pH value in perfused solution could modulate these currents. Here we aimed to examine the properties and modulation of the currents by serotonin or variation of pH value in hypoglossal motoneurons of rats. Transverse slices were prepared from the brainstem of neonatal Sprague-Dawley rats (postnatal days 7-8). Hypoglossal motoneurons were used for the study. The leak K(+) current (TASK-1-like current) and hyperpolarization-activated cationic current (I(h)) were recorded with the whole-cell patch-clamp technique. The results showed that these currents were inhibited by acidified artificial cerebrospinal fluid (ACSF, pH 6.0) and activated by alkalized ACSF (pH 8.5). 5-HT (10 mumol/L) significantly inhibited both leak K(+) current and I(h) with depolarization of membrane potential and the occurrence of oscillation and/or spikes. Bath application of Ketanserine, an antagonist of 5-HT₂ receptor, reversed or reduced the inhibitory effect of acidified solution on leak K(+) current and I(h). The results suggest that 5-HT₂ receptors mediate the effects of acidified media on leak K(+) current and I(h) in hypoglossal motoneurons.

  20. Influences of spray parameters on the structure and corrosion resistance of stainless steel layers coated on carbon steel by plasma spray treatment

    International Nuclear Information System (INIS)

    Yeom, Kyong An; Lee, Sang Dong; Kwon, Hyuk Sang; Shur, Dong Soo; Kim, Joung Soo

    1996-01-01

    Stainless steel powders were sprayed on the grit-blasted SM45C carbon steel substrates using a plasma spray method. The influences of the spray parameters on the structure and corrosion resistance of the layers coated on the carbon steel were investigated. Corrosion behavior of the layers were analyzed by the anodic polarization tests in deaerated 0.1 M NaCl + 0.01 M NaOH solution at 80 deg C. The surface roughness and porosity were observed to decrease with decreasing the particle size. The surface hardness of the coating was always higher than that of the matrix, SM45C, implying that the higher resistance of the coating to erosion-corrosion than that of matrix, and increased as the spray power and the spray distance increase. Stainless steel coats showed more corrosion resistance than the carbon steel did, due to their passivity. The corrosion resistance of the coats, however, were inferior to that of the bulk stainless steels due to the inherent defects formed in the coats. The defects such as rough surface and pores provided the occluded sites favorable for the initiation of localized corrosion, resulting in the conclusion that finer the powder is, higher the corrosion resistance is. And the Cr oxides formation resulting in Cr depletion around the oxides reduced the corrosion resistance of the coats. (author)

  1. Acoustic surveillance techniques for SGU leak monitoring

    International Nuclear Information System (INIS)

    McKnight, J.A.; Rowley, R.; Beesley, M.J.

    1990-01-01

    The paper presents a brief review of the acoustic techniques applicable to the detection of steam generator unit leaks that have been studied in the UK. Before discussion of the acoustic detection methods a reference representation of the required performance as developed in the UK is given. The conclusion is made that preliminary specification for the acoustic leak detection of sodium/water leaks in steam generating units suggests that it will be necessary to detect better than a leak rate of 3 g/s within a few seconds. 10 refs, 12 figs

  2. Analysis of a water-coolant leak into a very high-temperature vitrification chamber

    International Nuclear Information System (INIS)

    Felicione, F. S.

    1998-01-01

    A coolant-leakage incident occurred during non-radioactive operation of the Plasma Hearth Process waste-vitrification development system at Argonne National Laboratory when a stray electric arc ruptured az water-cooling jacket. Rapid evaporation of the coolant that entered the very high-temperature chamber pressurized the normally sub-atmospheric system above ambient pressure for over 13 minutes. Any positive pressurization, and particularly a lengthy one, is a safety concern since this can cause leakage of contaminants from the system. A model of the thermal phenomena that describe coolant/hot-material interactions was developed to better understand the characteristics of this type of incident. The model is described and results for a variety of hypothetical coolant-leak incidents are presented. It is shown that coolant leak rates above a certain threshold will cause coolant to accumulate in the chamber, and evaporation from this pool can maintain positive pressure in the system long after the leak has been stopped. Application of the model resulted in reasonably good agreement with the duration of the pressure measured during the incident. A closed-form analytic solution is shown to be applicable to the initial leak period in which the peak pressures are generated, and is presented and discussed

  3. Postoperative ascitic leaks: the ongoing challenge.

    Science.gov (United States)

    Rosemurgy, A S; Statman, R C; Murphy, C G; Albrink, M H; McAllister, E W

    1992-06-01

    The leak of ascitic fluid from surgical incisions is thought to be associated with a very high mortality rate. There have been few reports, however, focusing on the clinical characteristics, management, or mortality rates of this condition. During a 10-year period, 18 patients with postoperative ascitic fluid leaks were treated. All patients had ascites before surgery and all had liver disease; in 13 of the 18 patients alcoholic liver disease was the cause of ascites. Ten of the 18 patients died (56%). Midline incisions were more often associated with recalcitrant leaks and fatal complications than were transverse incisions. Early consideration of fascial dehiscence and prompt repair is emphasized. The most effective predictor of survival was cessation of the leak.

  4. Acoustic Leak Detection under Micro and Small Water Steam Leaks into Sodium for a Protection of the SFR Steam Generator

    International Nuclear Information System (INIS)

    Kim, Tae-Joon; Jeong, Ji-Young; Kim, Jong-Man; Kim, Byung-Ho; Hahn, Do-Hee; Yugay, Valeriy S.

    2008-01-01

    The results of an experimental study of water in a sodium leak noise spectrum formation related with a leak noise attenuation and absorption, and at various rates of water into a sodium leak, smaller than 1.0 g/s, are presented. We focused on studying the micro leak dynamics with an increasing rate of water into sodium owing to a self-development from 0.005 till 0.27 g/s. Conditions and ranges for the existence of bubbling and jetting modes in a water steam outflow into circulating sodium through an injector device, for simulating a defect in a wall of a heat-transmitting tube of a sodium water steam generator were determined. On the basis of the experimental leak noise data the simple dependency of an acoustic signal level from the rate of a micro and small leak at different frequency bands is presented to understand the principal analysis for the development of an acoustic leak detection methodology used in a K- 600 steam generator, with the operational experiences for the noise analysis and measurements in BN-600

  5. Non-spherical particle formation induced by repulsive hydration forces during spray drying

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Yong Jae; Lee, Jin-Woo; Chang, Hankwon; Jang, Hee-Dong, E-mail: hdjang@kigam.re.kr; Cho, Kuk, E-mail: kukcho@pusan.ac.kr [Korea Institute of Geoscience and Mineral Resources (Korea, Republic of)

    2013-09-15

    Non-spherical particles were produced during a spray-drying process, but the exact mechanism of their formation was unknown. The non-spherical particles form when the strength of the colloidal droplets is exceeded by external stress stemming from drag in the velocity gradient. Here, we show that repulsive hydration forces reduce the mechanical strength of the droplets; this is critical to the formation of non-spherical particles. Toroidal or ellipsoidal particles were prepared from low-concentration hydrophilic SiO{sub 2}, TiO{sub 2}, and CuO colloidal solutions, but not from hydrophobic ZnO colloidal solutions. The surface properties of the solid particulates are crucial for the morphology of particles formed during spray drying.

  6. Non-spherical particle formation induced by repulsive hydration forces during spray drying

    International Nuclear Information System (INIS)

    Suh, Yong Jae; Lee, Jin-Woo; Chang, Hankwon; Jang, Hee-Dong; Cho, Kuk

    2013-01-01

    Non-spherical particles were produced during a spray-drying process, but the exact mechanism of their formation was unknown. The non-spherical particles form when the strength of the colloidal droplets is exceeded by external stress stemming from drag in the velocity gradient. Here, we show that repulsive hydration forces reduce the mechanical strength of the droplets; this is critical to the formation of non-spherical particles. Toroidal or ellipsoidal particles were prepared from low-concentration hydrophilic SiO 2 , TiO 2 , and CuO colloidal solutions, but not from hydrophobic ZnO colloidal solutions. The surface properties of the solid particulates are crucial for the morphology of particles formed during spray drying

  7. A Correlated Active Acoustic Leak Detection in a SFR Steam Generator

    International Nuclear Information System (INIS)

    Kim, Tae Joon; Jeong, Ji Young; Kim, Jong Man; Kim, Byung Ho; Kim, Yong Il

    2009-01-01

    The methods of acoustic leak detection are active acoustic leak detection and passive acoustic leak detection. The methods for passive acoustic leak detection are already established, but because our goal is development of passive acoustic leak detection for detecting a leakage range of small and micro leak rates, it is difficult detecting a leak in steam generator using this developed passive acoustic leak detection. Thus the acoustic leak detection system is required to be able to detect wide range of water leaks. From this view point we need to develop an active acoustic leak detection technology to be able to detect intermediate leak rates

  8. Effects of nozzle type and spray angle on spray deposition in ivy pot plants.

    Science.gov (United States)

    Foqué, Dieter; Nuyttens, David

    2011-02-01

    Fewer plant protection products are now authorised for use in ornamental growings. Frequent spraying with the same product or a suboptimal technique can lead to resistance in pests and diseases. Better application techniques could improve the sustainable use of the plant protection products still available. Spray boom systems--instead of the still predominantly used spray guns--might improve crop protection management in greenhouses considerably. The effect of nozzle type, spray pressure and spray angle on spray deposition and coverage in ivy pot plants was studied, with a focus on crop penetration and spraying the bottom side of the leaves in this dense crop. The experiments showed a significant and important effect of collector position on deposition and coverage in the plant. Although spray deposition and coverage on the bottom side of the leaves are generally low, they could be improved 3.0-4.9-fold using the appropriate application technique. When using a spray boom in a dense crop, the nozzle choice, spray pressure and spray angle should be well considered. The hollow-cone, the air-inclusion flat-fan and the standard flat-fan nozzle with an inclined spray angle performed best because of the effect of swirling droplets, droplets with a high momentum and droplet direction respectively. Copyright © 2010 Society of Chemical Industry.

  9. Humos monitoring system of leaks in to the containment atmosphere

    International Nuclear Information System (INIS)

    Matal, O.; Zaloudek, J.; Matal, O. Jr.; Klinga, J.; Brom, J.

    1997-01-01

    HUmidity MOnitoring System (HUMOS) has been developed and designed to detect the presence of leak in selected primary circuit high energy pipelines and components that are evaluated from the point of view of Leak Before Break (LBB) requirements. It also requires to apply technical tools for detection and identification of coolant leaks from primary circuit and components of PWRs reactors. Safety significant of leaks depend on: leak source (location); leak rate, and leak duration. Therefore to detect and monitor coolant leaks in to the containment atmosphere during reactor operation is one of important safety measures. As potential leak sources flange connection in the upper head region of WWER reactors can be considered. HUMOS does not rely on the release of radioactivity to detect leaks but rather the relies on detection of moisture in the air resulting from a primary boundary leak. Because HUMOS relies on moisture and temperature detection, leaks can be detected without requiring the reactor to be critical. Therefore leaks can be detected during integrity pressure tests and any other mode of operation provided the reactor ventilation system is operating and primary circuit and components are pressurized. 3 figs

  10. Pipeline Leak Detection Techniques

    OpenAIRE

    Chis, Timur

    2009-01-01

    Leak detection systems range from simple, visual line walking and checking ones to complex arrangements of hard-ware and software. No one method is universally applicable and operating requirements dictate which method is the most cost effective. The aim of the paper is to review the basic techniques of leak detection that are currently in use. The advantages and disadvantages of each method are discussed and some indications of applicability are outlined.

  11. Pipeline Leak Detection Techniques

    Directory of Open Access Journals (Sweden)

    Timur Chis, Ph.D., Dipl.Eng.

    2007-01-01

    Full Text Available Leak detection systems range from simple, visual line walking and checking ones to complex arrangements of hard-ware and software. No one method is universally applicable and operating requirements dictate which method is the most cost effective. The aim of the paper is to review the basic techniques of leak detection that are currently in use. The advantages and disadvantages of each method are discussed and some indications of applicability are outlined.

  12. The effect of the solution flow rate on the properties of zinc oxide (ZnO) thin films deposited by ultrasonic spray

    International Nuclear Information System (INIS)

    Attaf, A.; Benkhetta, Y.; Saidi, H.; Bouhdjar, A.; Bendjedidi, H.; Nouadji, M.; Lehraki, N.

    2015-01-01

    In this work, we used a system based on ultrasonic spray pyrolysis technique. By witch, we have deposited thin films of zinc oxide (ZnO) with the variation of solution flow rate from 50 ml / h to 150 ml / h, and set other parameters such as the concentration of the solution, the deposition time, substrate temperature and the nozzel -substrate distance. In order to study the influence of the solution flow rate on the properties of the films produced, we have several characterization techniques such as X-ray diffraction to determine the films structure, the scanning electron microscopy SEM for the morphology of the surfaces, EDS spectroscopy for the chemical composition, UV-Visible-Nir spectroscopy for determination the optical proprieties of thin films.The experimental results show that: the films have hexagonal structure at the type (wurtzite), the average size of grains varies from 20.11 to 32.45 nm, the transmittance of the films equals 80% in visible rang and the band gap is varied between 3.274 and 3.282 eV, when the solution flow rate increases from 50 to 150 ml/h

  13. The effect of the solution flow rate on the properties of zinc oxide (ZnO) thin films deposited by ultrasonic spray

    Science.gov (United States)

    Attaf, A.; Benkhetta, Y.; Saidi, H.; Bouhdjar, A.; Bendjedidi, H.; Nouadji, M.; Lehraki, N.

    2015-03-01

    In this work, we used a system based on ultrasonic spray pyrolysis technique. By witch, we have deposited thin films of zinc oxide (ZnO) with the variation of solution flow rate from 50 ml / h to 150 ml / h, and set other parameters such as the concentration of the solution, the deposition time, substrate temperature and the nozzel -substrate distance. In order to study the influence of the solution flow rate on the properties of the films produced, we have several characterization techniques such as X-ray diffraction to determine the films structure, the scanning electron microscopy SEM for the morphology of the surfaces, EDS spectroscopy for the chemical composition, UV-Visible-Nir spectroscopy for determination the optical proprieties of thin films.The experimental results show that: the films have hexagonal structure at the type (wurtzite), the average size of grains varies from 20.11 to 32.45 nm, the transmittance of the films equals 80% in visible rang and the band gap is varied between 3.274 and 3.282 eV, when the solution flow rate increases from 50 to 150 ml/h.

  14. Probabilistic pipe fracture evaluations for leak-rate-detection applications

    International Nuclear Information System (INIS)

    Rahman, S.; Ghadiali, N.; Paul, D.; Wilkowski, G.

    1995-04-01

    Regulatory Guide 1.45, open-quotes Reactor Coolant Pressure Boundary Leakage Detection Systems,close quotes was published by the U.S. Nuclear Regulatory Commission (NRC) in May 1973, and provides guidance on leak detection methods and system requirements for Light Water Reactors. Additionally, leak detection limits are specified in plant Technical Specifications and are different for Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). These leak detection limits are also used in leak-before-break evaluations performed in accordance with Draft Standard Review Plan, Section 3.6.3, open-quotes Leak Before Break Evaluation Proceduresclose quotes where a margin of 10 on the leak detection limit is used in determining the crack size considered in subsequent fracture analyses. This study was requested by the NRC to: (1) evaluate the conditional failure probability for BWR and PWR piping for pipes that were leaking at the allowable leak detection limit, and (2) evaluate the margin of 10 to determine if it was unnecessarily large. A probabilistic approach was undertaken to conduct fracture evaluations of circumferentially cracked pipes for leak-rate-detection applications. Sixteen nuclear piping systems in BWR and PWR plants were analyzed to evaluate conditional failure probability and effects of crack-morphology variability on the current margins used in leak rate detection for leak-before-break

  15. Effect of emulsification and spray-drying microencapsulation on the antilisterial activity of transcinnamaldehyde.

    Science.gov (United States)

    Trinh, Nga-Thi-Thanh; Lejmi, Raja; Gharsallaoui, Adem; Dumas, Emilie; Degraeve, Pascal; Thanh, Mai Le; Oulahal, Nadia

    2015-01-01

    Spray-dried redispersible transcinnamaldehyde (TC)-in-water emulsions were prepared in order to preserve its antibacterial activity; 5% (w/w) TC emulsions were first obtained with a rotor-stator homogeniser in the presence of either soybean lecithin or sodium caseinate as emulsifiers. These emulsions were mixed with a 30% (w/w) maltodextrin solution before feeding a spray-dryer. The antibacterial activity of TC alone, TC emulsions with and without maltodextrin before and after spray-drying were assayed by monitoring the growth at 30 °C of Listeria innocua in their presence and in their absence (control). Whatever the emulsifier used, antilisterial activity of TC was increased following its emulsification. However, reconstituted spray-dried emulsions stabilised by sodium caseinate had a higher antibacterial activity suggesting that they better resisted to spray-drying. This was consistent with observation that microencapsulation efficiencies were 27.6% and 78.7% for emulsions stabilised by lecithin and sodium caseinate, respectively.

  16. Small liquid sodium leaks

    International Nuclear Information System (INIS)

    Dufresne, J.; Rochedereux, Y.; Antonakas, D.; Casselman, C.; Malet, J.C.

    1986-05-01

    Usually, pessimistic considerations inassessing the safety of secondary sodium loops in LMFBR reactor lead to assume guillotine rupture releasing a large amount of sodium estimate the consequences of large sodium fires. In order to reduce these consequences, one has to detect the smallest leak as soon as possible and to evaluate the future of an initial small leak. Analysis of the relationship between crack size and sodium outflow rate; Analysis of a sodium pipe with a small open crack

  17. Spray Formation of Herschel-Bulkley Fluids using Impinging Jets

    Science.gov (United States)

    Rodrigues, Neil; Gao, Jian; Chen, Jun; Sojka, Paul E.

    2015-11-01

    The impinging jet spray formation of two non-Newtonian, shear-thinning, Herschel-Bulkley fluids was investigated in this work. The water-based gelled solutions used were 1.0 wt.-% agar and 1.0 wt.-% kappa carrageenan. A rotational rheometer and a capillary viscometer were used to measure the strain-rate dependency of viscosity and the Herschel-Bulkley Extended (HBE) rheological model was used to characterize the shear-thinning behavior. A generalized HBE jet Reynolds number Rej , gen - HBE was used as the primary parameter to characterize the spray formation. A like-on-like impinging jet doublet was used to produce atomization. Shadowgraphs were captured in the plane of the sheet formed by the two jets using a CCD camera with an Nd:YAG laser beam providing the back-illumination. Typical behavior for impinging jet atomization using Newtonian liquids was not generally observed due to the non-Newtonian, viscous properties of the agar and kappa carrageenan gels. Instead various spray patterns were observed depending on Rej , gen - HBE. Spray characteristics of maximum instability wavelength and sheet breakup length were extracted from the shadowgraphs. Multi-University Research Initiative Grant Number W911NF-08-1-0171.

  18. Prioritizing Test Cases for Memory Leaks in Android Applications

    Institute of Scientific and Technical Information of China (English)

    Ju Qian; Di Zhou

    2016-01-01

    Mobile applications usually can only access limited amount of memory. Improper use of the memory can cause memory leaks, which may lead to performance slowdowns or even cause applications to be unexpectedly killed. Although a large body of research has been devoted into the memory leak diagnosing techniques after leaks have been discovered, it is still challenging to find out the memory leak phenomena at first. Testing is the most widely used technique for failure discovery. However, traditional testing techniques are not directed for the discovery of memory leaks. They may spend lots of time on testing unlikely leaking executions and therefore can be inefficient. To address the problem, we propose a novel approach to prioritize test cases according to their likelihood to cause memory leaks in a given test suite. It firstly builds a prediction model to determine whether each test can potentially lead to memory leaks based on machine learning on selected code features. Then, for each input test case, we partly run it to get its code features and predict its likelihood to cause leaks. The most suspicious test cases will be suggested to run at first in order to reveal memory leak faults as soon as possible. Experimental evaluation on several Android applications shows that our approach is effective.

  19. Stochastic Consequence Analysis for Waste Leaks

    International Nuclear Information System (INIS)

    HEY, B.E.

    2000-01-01

    This analysis evaluates the radiological consequences of potential Hanford Tank Farm waste transfer leaks. These include ex-tank leaks into structures, underneath the soil, and exposed to the atmosphere. It also includes potential misroutes, tank overflow

  20. Software-aided operation of modern industrial leak detectors

    Energy Technology Data Exchange (ETDEWEB)

    Grosse Bley, W. [INFICON GmbH, Koeln (Germany)

    2006-07-01

    When leak-testing parts with the tracer gas method, the ''no-indication'' response of the leak detector leaves the operator with the question whether there is really no leak present or the test instrument may be in a faulty (= insensitive) condition. Moreover, an operator being absent-minded or distracted may easily move the sniffer tip to the wrong spot on the test object or at least not to all required test areas. To make sure that the uncertainty about sensitivity is avoided specific artificial leaks (''test leaks'') are routinely used for frequent verification of the correct function and calibration of the leak detector. However, absent-minded, distracted or even lazy operators are not detected in this way. Recent software features implemented into INFICON leak detectors can help prevent mistakes of the above kind. Such features include intelligent filtering of the signal (preventing spurious noise), suppression of interfering gas effects, dynamic zeroing of the signal, simple on-site function tests with a built-in test leak, a complete spectrum of indications (optical, acoustical, tactile,..) if the trigger for leaky objects is exceeded and more. As an example of the latest achievements in this field the operator-controlling features of the new ECOTEC E3000 refrigerant leak detector from INFICON are described in some detail. It will become quite clear that product quality (in this case of refrigerators and air conditioners) is greatly enhanced by such supervising functions. (orig.)

  1. Means for preventing radioactive fluid leaking

    International Nuclear Information System (INIS)

    Akatsu, Jun-ichi.

    1975-01-01

    Object: To permit prevention of leakage of radioactive fluid from line and valve leak sections while also recovering the liquid by producing a vacuum state in a leak-off line by means of a water ejector. Structure: A portion of the water from a condenser is forced by a condensed water pump through a water ejector tank to a recovery tank while controlling an orifice and valve, whereby a vacuum state is produced in the leak-off line to withdraw the leakage fluid. (Kamimura, M.)

  2. Leak detection and location in MONJU steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Saito, T; Kosugi, T [Prototype Reactor Office, Tokyo (Japan)

    1978-10-01

    Leak detection system of MONJU steam generator depends mostly on in-sodium hydrogen detectors. The requirements on leak detector performance are determined from the point of view of protecting tube leak propagation due to wastage, and the process of determining the performance is shown briefly. Research and development activities on in-sodium hydrogen detectors are described and the specifications of leak detectors for MONJU are also presented. In-cover-gas hydrogen detector and acoustic detector are under development. Research and development activities on the leak location after steam generator shutdown by such methods as an electromagnetic method and ultrasonic method are described. The results of the research and development work on inserting the test probes into tubes are described also. An idea for finding the condition of tubes in the neighbourhood of the leak is also presented. (author)

  3. Leak detection and location in MONJU steam generators

    International Nuclear Information System (INIS)

    Saito, T.; Kosugi, T.

    1978-01-01

    Leak detection system of MONJU steam generator depends mostly on in-sodium hydrogen detectors. The requirements on leak detector performance are determined from the point of view of protecting tube leak propagation due to wastage, and the process of determining the performance is shown briefly. Research and development activities on in-sodium hydrogen detectors are described and the specifications of leak detectors for MONJU are also presented. In-cover-gas hydrogen detector and acoustic detector are under development. Research and development activities on the leak location after steam generator shutdown by such methods as an electromagnetic method and ultrasonic method are described. The results of the research and development work on inserting the test probes into tubes are described also. An idea for finding the condition of tubes in the neighbourhood of the leak is also presented. (author)

  4. Developments in steam generator leak detection at Ontario Hydro

    Energy Technology Data Exchange (ETDEWEB)

    Maynard, K.J.; Singh, V.P. [Ontario Hydro Technologies, Toronto, Ontario (Canada)

    1998-07-01

    A method for locating small tube leaks in steam generators has been developed and implemented at Ontario Hydro. The technique utilizes both helium leak detection and moisture leak detection. The combination of these two methods allows tube leaks to be detected in any part of the tube bundle, including those submerged below water near the tubesheet. The estimated detection limits for the helium and moisture leak detection systems are 0.001 kg/hr and 0.05 kg/hr respectively, expressed as leak rates measured at typical boiler operating conditions. This technology is best utilized in situations where the leak rate under operating conditions is smaller than the practical limit for fluorescein dye techniques ({approx}2 kg/hour). Other novel techniques have been utilized to increase the reliability and speed of the boiler leak search process. These include the use of argon carrier gas to stabilize the buoyant helium gas in the boiler secondary. (author)

  5. Developments in steam generator leak detection at Ontario Hydro

    International Nuclear Information System (INIS)

    Maynard, K.J.; Singh, V.P.

    1998-01-01

    A method for locating small tube leaks in steam generators has been developed and implemented at Ontario Hydro. The technique utilizes both helium leak detection and moisture leak detection. The combination of these two methods allows tube leaks to be detected in any part of the tube bundle, including those submerged below water near the tubesheet. The estimated detection limits for the helium and moisture leak detection systems are 0.001 kg/hr and 0.05 kg/hr respectively, expressed as leak rates measured at typical boiler operating conditions. This technology is best utilized in situations where the leak rate under operating conditions is smaller than the practical limit for fluorescein dye techniques (∼2 kg/hour). Other novel techniques have been utilized to increase the reliability and speed of the boiler leak search process. These include the use of argon carrier gas to stabilize the buoyant helium gas in the boiler secondary. (author)

  6. Nanosecond and femtosecond mass spectroscopic analysis of a molecular beam produced by the spray-jet technique

    International Nuclear Information System (INIS)

    Yamada, Toshiki; Shinohara, Hidenori; Kamikado, Toshiya; Okuno, Yoshishige; Suzuki, Hitoshi; Mashiko, Shinro; Yokoyama, Shiyoshi

    2008-01-01

    The spray-jet molecular beam apparatus enabled us to produce a molecular beam of non-volatile molecules under high vacuum from a sprayed mist of sample solutions. The apparatus has been used in spectroscopic studies and as a means of molecular beam deposition. We analyzed the molecular beam, consisting of non-volatile, solvent, and carrier-gas molecules, by using femtosecond- and nanosecond- laser mass spectroscopy. The information thus obtained provided insight into the molecular beam produced by the spray-jet technique

  7. Innovative approach to produce submicron drug particles by vibrational atomization spray drying: influence of the type of solvent and surfactant.

    Science.gov (United States)

    Durli, T L; Dimer, F A; Fontana, M C; Pohlmann, A R; Beck, R C R; Guterres, S S

    2014-08-01

    Spray drying is a technique used to produce solid particles from liquid solutions, emulsions or suspensions. Buchi Labortechnik developed the latest generation of spray dryers, Nano Spray Dryer B-90. This study aims to obtain, directly, submicron drug particles from an organic solution, employing this equipment and using dexamethasone as a model drug. In addition, we evaluated the influence of both the type of solvent and surfactant on the properties of the powders using a 3(2) full factorial analysis. The particles were obtained with high yields (above 60%), low water content (below 2%) and high drug content (above 80%). The surface tension and the viscosity were strongly influenced by the type of solvent. The highest powder yields were obtained for the highest surface tension and the lowest viscosity of the drug solutions. The use of ionic surfactants led to higher process yields. The laser diffraction technique revealed that the particles deagglomerate into small ones with submicrometric size, (around 1 µm) that was also observed by scanning electron microscopy. Interaction between the raw materials in the spray-dried powders was verified by calorimetric analysis. Thus, it was possible to obtain dexamethasone submicrometric particles by vibrational atomization from organic solution.

  8. Preparation of polymer-organo clay nano composites through the spray drying process

    International Nuclear Information System (INIS)

    Bernardo, Paulo R.A.; Pessan, Luiz A.; Carvalho, Antonio J.F. de; Vidotti, Suel E.

    2011-01-01

    The objective of the work was the study and preparation of polymer nano composites with montmorillonite organo clays (MMT) through the spray drying process. A new technique was proposed and tested to obtaining polymer nano composites, based on the use of the spray drying process to produce a nano composite with high clay content. The process consisted of the following stages: clay intercalation in water solution, with after addition of polyvinyl alcohol (PVOH) and a hydro soluble polyester ionomer (GEROLPS20) as exfoliation agents; spray drying the mixture obtained; incorporation powder in EVOH, PET e PP matrix. The effects of exfoliation agent on morphological and thermal properties of the nano composites were studied by XRD, transmission electron microscopy (TEM) and TGA. The results demonstrate that the process of spray drying is an innovative way to obtain a nano composite with high clay content. (author)

  9. Standard practice for leaks using ultrasonics

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 Practice A, Pressurization—This practice covers procedures for calibration of ultrasonic instruments, location, and estimated measurements of gas leakage to atmosphere by the airborne ultrasonic technique. 1.2 In general practice this should be limited to leaks detected by two classifications of instruments, Class I and Class II. Class I instruments should have a minimum detectable leak rate of 6.7 × 10−7 mol/s (1.5 × 10−2 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Class II instruments should have a minimal detectable leak rate of 6.7 × 10−6 mol/s (1.5 × 10−1 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Refer to Guide E432 for additional information. 1.3 Practice B, Ultrasonic Transmitter—For object under test not capable of being pressurized but capable of having ultrasonic tone placed/injected into the test area to act as an ultrasonic leak trace source. 1.3.1 This practice is limited to leaks producing leakage o...

  10. Measuring water ingestion from spray exposures.

    Science.gov (United States)

    Sinclair, Martha; Roddick, Felicity; Nguyen, Thang; O'Toole, Joanne; Leder, Karin

    2016-08-01

    Characterisation of exposure levels is an essential requirement of health risk assessment; however for water exposures other than drinking, few quantitative exposure data exist. Thus, regulatory agencies must use estimates to formulate policy on treatment requirements for non-potable recycled water. We adapted the use of the swimming pool chemical cyanuric acid as a tracer of recreational water ingestion to permit detection of small water volumes inadvertently ingested from spray exposures. By using solutions of 700-1000 mg/L cyanuric acid in an experimental spray exposure scenario, we were able to quantify inadvertent water ingestion in almost 70% of participants undertaking a 10 min car wash activity using a high pressure spray device. Skin absorption was demonstrated to be negligible under the experimental conditions, and the measured ingestion volumes ranged from 0.06 to 3.79 mL. This method could be applied to a range of non-potable water use activities to generate exposure data for risk assessment processes. The availability of such empirical measurements will provide greater assurance to regulatory agencies and industry that potential health risks from exposure to non-potable water supplies are well understood and adequately managed to protect public health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Improvement of the inlet system for the spray-jet technique for use in spectroscopic studies and molecular deposition

    International Nuclear Information System (INIS)

    Yamada, Toshiki; Shinohara, Hidenori; Mashiko, Shinro

    2006-01-01

    We previously developed a molecular beam apparatus with a spray-jet technique in order to produce a molecular beam of non-volatile molecules in vacuum from the sprayed mist of a sample solution. The apparatus is for use in spectroscopic studies or a means of molecular deposition. The spray-jet inlet system consisted of an ultrasonic nebulizer, an inlet chamber and a pulsed nozzle. In the present paper, further improvements to the spray-jet inlet system are reported. The main improvement is the introduction of a pneumatic nebulizer to replace the previous ultrasonic nebulizer. The efficiency of molecular beam generation was evaluated on the basis of the signal intensity of the resonantly enhanced multiphoton ionization time-of-flight mass (REMPI-TOFMS) spectra for a Rhodamine B/methanol solution and the amount of sample consumed. The introduction of the pneumatic nebulizer increased the efficiency by a factor of 20

  12. Wireless sensor network for sodium leak detection

    International Nuclear Information System (INIS)

    Satya Murty, S.A.V.; Raj, Baldev; Sivalingam, Krishna M.; Ebenezer, Jemimah; Chandran, T.; Shanmugavel, M.; Rajan, K.K.

    2012-01-01

    Highlights: ► Early detection of sodium leak is mandatory in any reactor handling liquid sodium. ► Wireless sensor networking technology has been introduced for detecting sodium leak. ► We designed and developed a wireless sensor node in-house. ► We deployed a pilot wireless sensor network for handling nine sodium leak signals. - Abstract: To study the mechanical properties of Prototype Fast Breeder Reactor component materials under the influence of sodium, the IN Sodium Test (INSOT) facility has been erected and commissioned at Indira Gandhi Centre for Atomic Research. Sodium reacts violently with air/moisture leading to fire. Hence early detection of sodium leak if any is mandatory for such plants and almost 140 sodium leak detectors are placed throughout the loop. All these detectors are wired to the control room for data collection and monitoring. To reduce the cost, space and maintenance that are involved in cabling, the wireless sensor networking technology has been introduced in the sodium leak detection system of INSOT. This paper describes about the deployment details of the pilot wireless sensor network and the measures taken for the successful deployment.

  13. Intelligent leak detection system for oil pipelines; Sistema inteligente para deteccao de vazamentos em dutos de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Ricardo Dantas Gadelha de [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2003-07-01

    One of the most challenging tasks in an oil field is implementation of a software-based leak detection system on a multi-phase flow pipeline. This paper will discuss implementation of a leak detection system in a particular oil field using state-of-the-art signal processing techniques to apply to the data collected in a oil pipeline. This leak detection system is still in development and uses a more practical approach to the problem than traditional methods and was implemented on a PC under the Windows operating system. Windowing, joint time-frequency analysis and wavelets were considered to develop methods of detecting leaks by watching for the wavefront. The idea behind these techniques is to cut the signal of interest into several parts and then analyze the parts separately. It is impossible to know the exact frequency and the exact time of occurrence of the leak frequency in a signal. In other words, a leak signal can simply not be represented as a point in the time-frequency space. It is very important how one cuts the signal to implement the analysis. The wavelet transform or wavelet analysis is probably the most recent solution to overcome the shortcomings of the Fourier transform. So, this paper shows some tests and how these techniques are being implementing during the development of the system. (author)

  14. WRSS jumper leak assessment

    International Nuclear Information System (INIS)

    BAILEY, J.W.

    1999-01-01

    The purpose of this assessment is: (1) to assemble and document the facts associated with three recently installed jumpers which have leaked either during actual process operation or during post installation testing; (2) to describe the corrective actions taken and to identify any process improvements which need to be implemented in the Hanford jumper design and installation activities; and (3) to document WRSS jumper leak lessons learned for use by future projects and other jumper design, fabrication, and installation activities

  15. Spray dried amikacin powder for inhalation in cystic fibrosis patients: a quality by design approach for product construction.

    Science.gov (United States)

    Belotti, Silvia; Rossi, Alessandra; Colombo, Paolo; Bettini, Ruggero; Rekkas, Dimitrios; Politis, Stavros; Colombo, Gaia; Balducci, Anna Giulia; Buttini, Francesca

    2014-08-25

    An amikacin product for convenient and compliant inhalation in cystic fibrosis patients was constructed by spray-drying in order to produce powders of pure drug having high respirability and flowability. An experimental design was applied as a statistical tool for the characterization of amikacin spray drying process, through the establishment of mathematical relationships between six Critical Quality Attributes (CQAs) of the finished product and five Critical Process Parameters (CPPs). The surface-active excipient, PEG-32 stearate, studied for particle engineering, in general did not benefit the CQAs of the spray dried powders for inhalation. The spray drying feed solution required the inclusion of 10% (v/v) ethanol in order to reach the desired aerodynamic performance of powders. All desirable function solutions indicated that the favourable concentration of amikacin in the feed solution had to be kept at 1% w/v level. It was found that when the feed rate of the sprayed solution was raised, an increase in the drying temperature to the maximum value (160 °C) was required to maintain good powder respirability. Finally, the increase in drying temperature always led to an evident increase in emitted dose (ED) without affecting the desirable fine particle dose (FPD) values. The application of the experimental design enabled us to obtain amikacin powders with both ED and FPD, well above the regulatory and scientific references. The finished product contained only the active ingredient, which keeps low the mass to inhale for dose requirement. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Toluene removal by oxidation reaction in spray wet scrubber: experimental, modeling and optimization

    Directory of Open Access Journals (Sweden)

    Roumporn Nikom

    2006-11-01

    Full Text Available Toluene, an important volatile organic compound (VOC, is used in many kinds of industries, such as painting, printing, coating, and petrochemical industries. The emission of toluene causes serious air pollution, odor problem, flammability problem and affects human health. This paper proposes the removal of toluene from waste air using a spray wet scrubber combining the absorption and oxidation reaction. Aqueous sodium hypochlorite (NaOCl solution was used as the scrubbing liquid in the system. NaOCl, the strongest oxidative agent, presents an effective toluene removal. As the scrubbed toluene is reacted, recirculation of the scrubbing liquid could be operated with a constant removal efficiency throughout the operting time. The investigated variables affecting the removal efficiency were air flow rate, inlet toluene concentration, NaOCl concentration, scrubbing liquid flow rate and size of spray nozzle. Influence of the scrubbing parameters was experimentally studied to develop a mathematical model of the toluene removal efficiency. The removal model reveals that the increase of scrubbing liquid flow rate, toluene concentration, and NaOCl concentration together with the decrease of air flow rate and size of spray nozzle can increase the toluene removal efficiency. Optimization problem with an objective function and constraints was set to provide the maximum toluene removal efficiency and solved by Matlab optimization toolbox. The optimization constraints were formed from the mathematical model and process limitation. The solution of the optimization was an air flow rate of 100 m3/h, toluene concentration of 1500 ppm, NaOCl concentration of 0.02 mol/l, NaOCl solution feed rate of 0.8 m3/h, and spray nozzle size of 0.5 mm. Solution of the optimization gave the highest toluene removal efficiency of 91.7%.

  17. Water leaks in sodium-heated fast reactor boilers

    International Nuclear Information System (INIS)

    Hayes, D.J.

    1978-01-01

    Constraints on plant design which may result from considerations of leak behaviour and leak detection limits are briefly considered. The sodium-water interface and reactions, the behaviour of small leaks, hydrogen bubbles and detection methods, including galvanic cell methods, are included. (UK)

  18. Effect of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} powder addition in the precursor solution on the properties of cathode films deposited by spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Caio Luis Santos; Rangel, Maria do Carmo, E-mail: clssilva@ufba.br, E-mail: mcarmov@ufba.br [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Grupo de Estudo em Cinetica e Catalise; Gama, Leonardo Marques; Paes Junior, Herval Ramos, E-mail: leonardo.m.gama@gmail.com, E-mail: herval@uenf.br [Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, RJ (Brazil). Laboratorio de Materiais Avancados; Santos, Jacqueline Amanda Figueiredo dos; Domingues, Rosana Zacarias, E-mail: jac.amanda28@gmail.com, E-mail: rosanazd@ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Laboratorio de Materiais e Pilhas a Combustivel

    2017-01-15

    Films of lanthanum strontium manganite, LSM (La{sub 0.8}Sr{sub 0.2}MnO{sub 3}) were deposited on yttria stabilized zirconia (YSZ) substrates by different methods aiming to establish the most suitable route to prepare cathodes for solid oxide fuel cells (SOFC). Samples were obtained by using a solution of lanthanum, strontium and manganese nitrates or a dispersion of the LSM powder in this solution. Both commercial and synthesized LSM powders were used, the last one obtained by amorphous citrate method. The films were deposited by spray pyrolysis on YSZ substrates prepared by uniaxial and isostatic pressing. Samples were characterized by scanning electron microscopy, confocal laser scanning microscopy, X-ray diffraction and two-probe conductivity measurements. The area specific resistance and relaxation to cathodic activation were measured by electrochemical impedance spectroscopy. The substrate obtained by uniaxial pressing and the commercial LSM produced films with the highest amount of surface cracks. The film obtained from the suspension showed area specific resistance and activation energy lower than the other produced from the solution. For both samples, the cathodic activation process resulted in an initial reduction of the total resistance of around 20%, the sample produced from the suspension being more resistant to relaxation. Therefore, the LSM suspension is more suitable than the salts solution for preparing films by spray pyrolysis on YSZ substrates to obtain efficient cathodes for SOFC. (author)

  19. Dynamic pressure measures for long pipeline leak detection

    Energy Technology Data Exchange (ETDEWEB)

    Likun Wang; Hongchao Wang; Min Xiong; Bin Xu; Dongjie Tan; Hengzhang Zhou [PetroChina Pipeline Company, Langfang (China). R and D Center

    2009-07-01

    Pipeline leak detection method based on dynamic pressure is studied. The feature of dynamic pressure which is generated by the leakage of pipeline is analyzed. The dynamic pressure method is compared with the static pressure method for the advantages and disadvantages in pipeline leak detection. The dynamic pressure signal is suitable for pipeline leak detection for quick-change of pipeline internal pressure. Field tests show that the dynamic pressure method detects pipeline leak rapidly and precisely. (author)

  20. Hepatobiliary scintigraphy in patients with bile leaks

    International Nuclear Information System (INIS)

    Carichner, S.L.; Nagle, C.E.

    1987-01-01

    Hepatobiliary scintigraphy has been recognized as a useful tool in detecting the presence and sites of bile leaks. The clinical settings in which bile leaks are likely to occur, as well as some of the scintigraphic patterns seen in patients with bile leaks, are reviewed here. Tips for technologists are offered on interventions that might enhanced the quality of information available to the nuclear physician

  1. Field tests and commercialization of natural gas leak detectors

    Energy Technology Data Exchange (ETDEWEB)

    Choi, D S; Jeon, J S; Kim, K D; Cho, Y A [R and D Center, Korea Gas Corporation, Ansan (Korea)

    1999-09-01

    Objectives - (1) fields test of industrial gas leak detection monitoring system. (2) commericialization of residential gas leak detector. Contents - (1) five sets of gas leak detection monitoring system were installed at natural gas transmition facilities and tested long term stability and their performance. (2) improved residential gas leak detector was commercialised. Expected benefits and application fields - (1) contribution to the improvement of domestic gas sensor technology. (2) localization of fabrication technology for gas leak detectors. 23 refs., 126 figs., 37 tabs.

  2. The benefits of SCADA integrated pipeline leak detection

    Energy Technology Data Exchange (ETDEWEB)

    Pichler, Ruprecht M.J. [Pichler Engineering GmbH, Munich (Germany)

    2003-07-01

    Software based leak detection and locating for pipelines based upon evaluation of hydraulic parameters is a widely used approach to online pipeline integrity monitoring. Typically, these software packages are installed in a stand-alone configuration with a narrow bandwidth interface to the pipeline SCADA system. However, the performance characteristics of the SCADA system and interface do have a substantial impact on the performance of the leak detection system. By a tight integration of leak detection software into the SCADA system, a source of false alarms typically experienced with leak detection systems can be eliminated, the overall performance of the leak detection system can be improved, and the project costs can be reduced. (author)

  3. Successful Endoscopic Therapy of Traumatic Bile Leaks

    Directory of Open Access Journals (Sweden)

    Matthew P. Spinn

    2013-02-01

    Full Text Available Traumatic bile leaks often result in high morbidity and prolonged hospital stay that requires multimodality management. Data on endoscopic management of traumatic bile leaks are scarce. Our study objective was to evaluate the efficacy of the endoscopic management of a traumatic bile leak. We performed a retrospective case review of patients who were referred for endoscopic retrograde cholangiopancreatography (ERCP after traumatic bile duct injury secondary to blunt (motor vehicle accident or penetrating (gunshot trauma for management of bile leaks at our tertiary academic referral center. Fourteen patients underwent ERCP for the management of a traumatic bile leak over a 5-year period. The etiology included blunt trauma from motor vehicle accident in 8 patients, motorcycle accident in 3 patients and penetrating injury from a gunshot wound in 3 patients. Liver injuries were grade III in 1 patient, grade IV in 10 patients, and grade V in 3 patients. All patients were treated by biliary stent placement, and the outcome was successful in 14 of 14 cases (100%. The mean duration of follow-up was 85.6 days (range 54-175 days. There were no ERCP-related complications. In our case review, endoscopic management with endobiliary stent placement was found to be successful and resulted in resolution of the bile leak in all 14 patients. Based on our study results, ERCP should be considered as first-line therapy in the management of traumatic bile leaks.

  4. Preparation of sustained-release coated particles by novel microencapsulation method using three-fluid nozzle spray drying technique.

    Science.gov (United States)

    Kondo, Keita; Niwa, Toshiyuki; Danjo, Kazumi

    2014-01-23

    We prepared sustained-release microcapsules using a three-fluid nozzle (3N) spray drying technique. The 3N has a unique, three-layered concentric structure composed of inner and outer liquid nozzles, and an outermost gas nozzle. Composite particles were prepared by spraying a drug suspension and an ethylcellulose solution via the inner and outer nozzles, respectively, and mixed at the nozzle tip (3N-PostMix). 3N-PostMix particles exhibited a corrugated surface and similar contact angles as ethylcellulose bulk, thus suggesting encapsulation with ethylcellulose, resulting in the achievement of sustained release. To investigate the microencapsulation process via this approach and its usability, methods through which the suspension and solution were sprayed separately via two of the four-fluid nozzle (4N) (4N-PostMix) and a mixture of the suspension and solution was sprayed via 3N (3N-PreMix) were used as references. It was found that 3N can obtain smaller particles than 4N. The results for contact angle and drug release corresponded, thus suggesting that 3N-PostMix particles are more effectively coated by ethylcellulose, and can achieve higher-level controlled release than 4N-PostMix particles, while 3N-PreMix particles are not encapsulated with pure ethylcellulose, leading to rapid release. This study demonstrated that the 3N spray drying technique is useful as a novel microencapsulation method. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Stacking layered structure of polymer light emitting diodes prepared by evaporative spray deposition using ultradilute solution for improving carrier balance

    International Nuclear Information System (INIS)

    Aoki, Youichi; Shakutsui, Masato; Fujita, Katsuhiko

    2009-01-01

    Polymer light-emitting diodes (PLEDs) with staking layered structures are prepared by the evaporative spray deposition using ultradilute solution (ESDUS) method, which has enabled forming a polymer layer onto another polymer layer even if both polymers are soluble in a solvent used for the preparation. By this method, polymers having various HOMO and LUMO levels can be stacked as a hole transport layer, an emitting layer and an electron transport layer as commonly employed in small molecule-based organic light emitting diodes. Here we demonstrated that a PLED having a tri-layer structure using three kinds of polymers showed significant improvement in quantum efficiency compared with those having a single or bi-layer structure of corresponding polymers.

  6. Dynamic modelling and real-time leak detection for NGL pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Young, B.R.; Svrcek, W.Y. [Calgary Univ., AB (Canada). Dept. of Chemical and Petroleum Engineering; Cooke, J.G.; Daye, R.E. [Rangeland Engineering Ltd., Calgary, AB (Canada)

    2004-07-01

    This paper presented newly developed steady-state and dynamic models commissioned for natural gas liquids (NGL) pipelines near Empress, Alberta. The work demonstrates a unique university-industry collaboration for solving the challenge of reliable pipeline leak detection. The flexible, custom real-time leak detection system was tested on the dynamic simulation. It was successfully used to replace a volume balance system for NGL pipelines at Empress in March 2003. A custom pipeline monitoring system was also developed to integrate with the existing pipeline supervisory control and data acquisition (SCADA) system. Simulation results enabled a change in the control scheme of the pipelines that resulted in less transient operation. The premise of the leak detection system is a rigorous thermodynamics and dynamic mass balance calculation based on real-time information from field flow, pressure and temperature sensors. The application of the system makes it possible to minimize or eliminate false or nuisance alarms, which is critical to the confidence of the monitoring system. The volumetric and mass imbalance formulae permit the system to cross check the calculation and then make important decisions regarding the sounding of alarms. The custom solution offers flexibility for use in a wide variety of conditions and applications. In addition, it is cost effective and locally supported. 8 refs., 4 tabs., 5 figs.

  7. Detection of primary coolant leaks in NPP

    International Nuclear Information System (INIS)

    Slavov, S.; Bakalov, I.; Vassilev, H.

    2001-01-01

    The thermo-hydraulic analyses of the SG box behaviour of Kozloduy NPP units 3 and 4 in case of small primary circuit leaks and during normal operation of the existing ventilation systems in order to determine the detectable leakages from the primary circuit by analysing different parameters used for the purposes of 'Leak before break' concept, performed by ENPRO Consult Ltd. are presented. The following methods for leak detection: measurement of relative air humidity in SG box (can be used for detection of leaks with flow rate 3.78 l/min within one hour at ambient parameters - temperature 40 0 - 60 0 C and relative humidity form 30% to 60%); measurement of water level in SG box sumps (can not be used for reliable detection of small primary circuit leakages with flow rate about 3.78 l/min); measurement of gaseous radioactivity in SG box( can be used as a general global indication for detection of small leakages from the primary circuit); measurement of condensate flow after the air coolers of P-1 venting system (can be used for primary circuit leak detection) are considered. For determination of the confinement behaviour, a model used with computer code MELCOR has been developed by ENPRO Consult Ltd. A brief summary based on the capabilities of the different methods of leak detection, from the point of view of the applicability of a particular method is given. For both Units 3 and 4 of Kozloduy NPP a qualified complex system for small leak detection is planned to be constructed. Such a system has to unite the following systems: acoustic system for leak detection 'ALUS'; system for control of the tightness of the main primary circuit pipelines by monitoring the local humidity; system for primary circuit leakage detection by measuring condensate run-off in collecting tank after ventilation system P-1 air coolers

  8. He leak testing of Indus-2 dipole vacuum chambers

    International Nuclear Information System (INIS)

    Sindal, B.K.; Bhavsar, S.T.; Shukla, S.K.

    2003-01-01

    Full text: Centre for Advanced Technology is developing its second synchrotron radiation source INDUS-2 which is a 2.5 GeV electron storage ring. Dipole vacuum chambers are the vital components of Indus-2 vacuum system. Each of these chambers is approx. 3.6 m long and 0.67 m wide with 24 nos. of ports of various sizes. The dipole chambers were made by machining two halves and they are then lip welded together. The dipole chamber has approx. 14 m of total weld length and it was leak tested for leak tightness of the order of 10 -10 mbar 1/s. Helium mass spectrometer leak detector (HMSLD) was utilized for the leak testing. Subsequently the leaks of various orders in welding joints were repaired and leak tightness achieved. This paper describes the experiences during leak testing of 20 nos. of aluminum dipole chambers for INDUS-2

  9. Effect of ethanol as a co-solvent on the aerosol performance and stability of spray-dried lysozyme

    DEFF Research Database (Denmark)

    Ji, Shuying; Thulstrup, Peter Waaben; Mu, Huiling

    2016-01-01

    In the spray drying process, organic solvents can be added to facilitate drying, accommodate certain functional excipients, and modify the final particle characteristics. In this study, lysozyme was used as a model pharmaceutical protein to study the effect of ethanol as a co...... the spray drying process. The enzymatic activities of the spray-dried lysozyme showed no significant impact of ethanol; however, the lysozyme enzymatic activity was ca. 25% lower compared to the starting material. In conclusion, the addition of ethanol as a co-solvent in the spray drying feed for lysozyme......-solvent on the stability and aerosol performance of spray-dried protein. Lysozyme was dissolved in solutions with various ratios of ethanol and water, and subsequently spray-dried. A change from spherical particles into wrinkled and folded particles was observed upon increasing the ratio of ethanol in the feed...

  10. ISS Ammonia Leak Detection Through X-Ray Fluorescence

    Science.gov (United States)

    Camp, Jordan; Barthelmy, Scott; Skinner, Gerry

    2013-01-01

    Ammonia leaks are a significant concern for the International Space Station (ISS). The ISS has external transport lines that direct liquid ammonia to radiator panels where the ammonia is cooled and then brought back to thermal control units. These transport lines and radiator panels are subject to stress from micrometeorites and temperature variations, and have developed small leaks. The ISS can accommodate these leaks at their present rate, but if the rate increased by a factor of ten, it could potentially deplete the ammonia supply and impact the proper functioning of the ISS thermal control system, causing a serious safety risk. A proposed ISS astrophysics instrument, the Lobster X-Ray Monitor, can be used to detect and localize ISS ammonia leaks. Based on the optical design of the eye of its namesake crustacean, the Lobster detector gives simultaneously large field of view and good position resolution. The leak detection principle is that the nitrogen in the leaking ammonia will be ionized by X-rays from the Sun, and then emit its own characteristic Xray signal. The Lobster instrument, nominally facing zenith for its astrophysics observations, can be periodically pointed towards the ISS radiator panels and some sections of the transport lines to detect and localize the characteristic X-rays from the ammonia leaks. Another possibility is to use the ISS robot arm to grab the Lobster instrument and scan it across the transport lines and radiator panels. In this case the leak detection can be made more sensitive by including a focused 100-microampere electron beam to stimulate X-ray emission from the leaking nitrogen. Laboratory studies have shown that either approach can be used to locate ammonia leaks at the level of 0.1 kg/day, a threshold rate of concern for the ISS. The Lobster instrument uses two main components: (1) a microchannel plate optic (also known as a Lobster optic) that focuses the X-rays and directs them to the focal plane, and (2) a CCD (charge

  11. Reactor container spray device

    International Nuclear Information System (INIS)

    Yanai, Ryoichi.

    1980-01-01

    Purpose: To enable decrease in the heat and the concentration of radioactive iodine released from the reactor vessel into the reactor container in the spray device of BWR type reactors. Constitution: A plurality of water receiving trays are disposed below the spray nozzle in the dry well and communicated to a pressure suppression chamber by way of drain pipeways passing through a diaphragm floor. When the recycling system is ruptured and coolants in the reactor vessel and radioactive iodine in the reactor core are released into the dry well, spray water is discharged from the spray nozzle to eliminate the heat and the radioactive iodine in the dry well. In this case, the receiving trays collect the portions of spray water whose absorption power for the heat and radioactive iodine is nearly saturated and falls them into the pool water of the pressure suppression chamber. Consequently, other portions of the spray water that still possess absorption power can be jetted with no hindrance, to increase the efficiency for the removal of the heat and iodine of the spray droplets. (Horiuchi, T.)

  12. Prospective randomized trial compares suction versus water seal for air leaks.

    Science.gov (United States)

    Cerfolio, R J; Bass, C; Katholi, C R

    2001-05-01

    Surgeons treat air leaks differently. Our goal was to evaluate whether it is better to place chest tubes on suction or water seal for stopping air leaks after pulmonary surgery. A second goal was to evaluate a new classification system for air leaks that we developed. Patients were prospectively randomized before surgery to receive suction or water seal to their chest tubes on postoperative day (POD) #2. Air leaks were described and quantified daily by a classification system and a leak meter. The air-leak meter scored leaks from 1 (least) to 7 (greatest). The group randomized to water seal stayed on water seal unless a pneumothorax developed. On POD #2, 33 of 140 patients had an air leak. Eighteen patients had been preoperatively randomized to water seal and 15 to suction. Air leaks resolved in 12 (67%) of the water seal patients by the morning of POD #3. All 6 patients whose air leak did not stop had a leak that was 4/7 or greater (p leak meter. Of the 15 patients randomized to suction, only 1 patient's air leak (7%) resolved by the morning of POD #3. The randomization aspect of the trial was ended and statistical analysis showed water seal was superior (p = 0.001). The remaining 14 patients were then placed to water seal and by the morning of POD #4, 13 patients' leaks had stopped. Of the 32 total patients placed to seal, 7 (22%) developed a pneumothorax and 6 of these 7 patients had leaks that were 4/7 or greater (p = 0.001). Placing chest tubes on water seal seems superior to wall suction for stopping air leaks after pulmonary resection. However, water seal does not stop expiratory leaks that are 4/7 or greater. Pneumothorax may occur when chest tubes are placed on seal with leaks this large.

  13. Slurry spray distribution within a simulated laboratory scale spray dryer

    International Nuclear Information System (INIS)

    Bertone, P.C.

    1979-01-01

    It was found that the distribution of liquid striking the sides of a simulated room temperature spray dryer was not significantly altered by the choice of nozles, nor by a variation in nozzle operating conditions. Instead, it was found to be a function of the spray dryer's configuration. A cocurrent flow of air down the drying cylinder, not possible with PNL's closed top, favorably altered the spray distribution by both decreasing the amount of liquid striking the interior of the cylinder from 72 to 26% of the feed supplied, and by shifting the zone of maximum impact from 1.0 to 1.7 feet from the nozzle. These findings led to the redesign of the laboratory scale spray dryer to be tested at the Savannah River Plant. The diameter of the drying chamber was increased from 5 to 8 inches, and a cocurrent flow of air was established with a closed recycle. Finally, this investigation suggested a drying scheme which offers all the advantages of spray drying without many of its limitations

  14. Plasma Sprayed Hydroxyapatite Coatings: Influence of Spraying Power on Microstructure

    International Nuclear Information System (INIS)

    Mohd, S. M.; Abd, M. Z.; Abd, A. N.

    2010-01-01

    The plasma sprayed hydroxyapatite (HA) coatings are used on metallic implants to enhance the bonding between the implant and bone in human body. The coating process was implemented at different spraying power for each spraying condition. The coatings formed from a rapid solidification of molten and partly molten particles that impact on the surface of substrate at high velocity and high temperature. The study was concentrated on different spraying power that is between 23 to 31 kW. The effect of different power on the coatings microstructure was investigated using scanning electron microscope (SEM) and phase composition was evaluated using X-ray diffraction (XRD) analysis. The coatings surface morphology showed distribution of molten, partially melted particles and some micro-cracks. The produced coatings were found to be porous as observed from the cross-sectional morphology. The coatings XRD results indicated the presence of crystalline phase of HA and each of the patterns was similar to the initial powder. Regardless of different spraying power, all the coatings were having similar XRD patterns.

  15. 1999 Leak Detection, Monitoring, and Mitigation Strategy Update

    International Nuclear Information System (INIS)

    OHL, P.C.

    1999-01-01

    This document is a complete revision of WHC-SD-WM-ES-378, Rev 1. This update includes recent developments in Leak Detection, Leak Monitoring, and Leak Mitigation technologies, as well as, recent developments in single-shell tank retrieval technologies. In addition, a single-shell tank retrieval release protection strategy is presented

  16. Capillary leak syndrome: etiologies, pathophysiology, and management.

    Science.gov (United States)

    Siddall, Eric; Khatri, Minesh; Radhakrishnan, Jai

    2017-07-01

    In various human diseases, an increase in capillary permeability to proteins leads to the loss of protein-rich fluid from the intravascular to the interstitial space. Although sepsis is the disease most commonly associated with this phenomenon, many other diseases can lead to a "sepsis-like" syndrome with manifestations of diffuse pitting edema, exudative serous cavity effusions, noncardiogenic pulmonary edema, hypotension, and, in some cases, hypovolemic shock with multiple-organ failure. The term capillary leak syndrome has been used to describe this constellation of disease manifestations associated with an increased capillary permeability to proteins. Diseases other than sepsis that can result in capillary leak syndrome include the idiopathic systemic capillary leak syndrome or Clarkson's disease, engraftment syndrome, differentiation syndrome, the ovarian hyperstimulation syndrome, hemophagocytic lymphohistiocytosis, viral hemorrhagic fevers, autoimmune diseases, snakebite envenomation, and ricin poisoning. Drugs including some interleukins, some monoclonal antibodies, and gemcitabine can also cause capillary leak syndrome. Acute kidney injury is commonly seen in all of these diseases. In addition to hypotension, cytokines are likely to be important in the pathophysiology of acute kidney injury in capillary leak syndrome. Fluid management is a critical part of the treatment of capillary leak syndrome; hypovolemia and hypotension can cause organ injury, whereas capillary leakage of administered fluid can worsen organ edema leading to progressive organ injury. The purpose of this article is to discuss the diseases other than sepsis that produce capillary leak and review their collective pathophysiology and treatment. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  17. Process for the recovery of alkali metal salts from aqueous solutions thereof

    International Nuclear Information System (INIS)

    Vitner, J.

    1984-01-01

    In an integrated process for the recovery of alkakli metal phenates and carboxylates from aqueous solutions thereof, the aqueous solution is spray dried and the drying gas stream is contacted with an aqueous alkali metal salt solution which dissolves the particles of the alkali metal salt that were entrained in the drying gas stream. The salt-free inert gas stream is then dried, heated, and returned to the spray dryer

  18. Development of pressure boundaries leak detection technology for nuclear reactor

    International Nuclear Information System (INIS)

    Zhang Yao; Zhang Dafa; Chen Dengke; Zhang Liming

    2008-01-01

    The leak detection for the pressure boundaries is an important safeguard in nuclear reactor operation. In the paper, the status and the characters on the development of the pressure boundaries leak detection technology for the nuclear reactor were reviewed, especially, and the advance of the radiation leak detection technology and the acoustic emission leak detection technology were analyzed. The new advance trend of the leak detection technology was primarily explored. According to the analysis results, it is point out that the advancing target of the leak detection technology is to enhance its response speed, sensitivity, and reliability, and to provide effective information for operator and decision-maker. The realization of the global leak detection and the whole life cycle health monitoring for the nuclear boundaries is a significant advancing tendency of the leak detection technology. (authors)

  19. Locating Leaks with TrustRank Algorithm Support

    Directory of Open Access Journals (Sweden)

    Luísa Ribeiro

    2015-03-01

    Full Text Available This paper presents a methodology to quantify and to locate leaks. The original contribution is the use of a tool based on the TrustRank algorithm for the selection of nodes for pressure monitoring. The results from these methodologies presented here are: (I A sensitivity analysis of the number of pressure transducers on the quality of the final solution; (II A reduction of the number of pipes to be inspected; and (III A focus on the problematic pipes which allows a better office planning of the inspection works to perform atthe field. To obtain these results, a methodology for the identification of probable leaky pipes and an estimate of their leakage flows is also presented. The potential of the methodology is illustrated with several case studies, considering different levels of water losses and different sets of pressure monitoring nodes. The results are discussed and the solutions obtained show the benefits of the developed methodologies.

  20. LMFBR steam generator leak detection development in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Magee, P M; Gerrels, E E; Greene, D A [General Electric Company, Sunnyvale, CA (United States); McKee, J [Argonne National Laboratory, Argonne, IL (United States)

    1978-10-01

    Leak detection for Liquid Metal Fast Breeder Reactor steam generators is an important economic factor in the shutdown, repair and restart of a plant. Development of leak detection systems in the U.S. has concentrated on four areas: (1) chemical (H{sub 2} and O{sub 2}) leak detection meters; (2) acoustic leak detection/location techniques; (3) investigation of leak behavior (enlargement, damage effects, plugging and unplugging); and (4) data management for plant operations. This paper discusses the status, design aspects, and applications of leak detection technology for LMFBR plants. (author)

  1. LMFBR steam generator leak detection development in the United States

    International Nuclear Information System (INIS)

    Magee, P.M.; Gerrels, E.E.; Greene, D.A.; McKee, J.

    1978-01-01

    Leak detection for Liquid Metal Fast Breeder Reactor steam generators is an important economic factor in the shutdown, repair and restart of a plant. Development of leak detection systems in the U.S. has concentrated on four areas: (1) chemical (H 2 and O 2 ) leak detection meters; (2) acoustic leak detection/location techniques; (3) investigation of leak behavior (enlargement, damage effects, plugging and unplugging); and (4) data management for plant operations. This paper discusses the status, design aspects, and applications of leak detection technology for LMFBR plants. (author)

  2. Inhaled nitric oxide pretreatment but not posttreatment attenuates ischemia-reperfusion-induced pulmonary microvascular leak.

    Science.gov (United States)

    Chetham, P M; Sefton, W D; Bridges, J P; Stevens, T; McMurtry, I F

    1997-04-01

    Ischemia-reperfusion (I/R) pulmonary edema probably reflects a leukocyte-dependent, oxidant-mediated mechanism. Nitric oxide (NO) attenuates leukocyte-endothelial cell interactions and I/R-induced microvascular leak. Cyclic adenosine monophosphate (cAMP) agonists reverse and prevent I/R-induced microvascular leak, but reversal by inhaled NO (INO) has not been tested. In addition, the role of soluble guanylyl cyclase (sGC) activation in the NO protection effect is unknown. Rat lungs perfused with salt solution were grouped as either I/R, I/R with INO (10 or 50 ppm) on reperfusion, or time control. Capillary filtration coefficients (Kfc) were estimated 25 min before ischemia (baseline) and after 30 and 75 min of reperfusion. Perfusate cell counts and lung homogenate myeloperoxidase activity were determined in selected groups. Additional groups were treated with either INO (50 ppm) or isoproterenol (ISO-10 microM) after 30 min of reperfusion. Guanylyl cyclase was inhibited with 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ-15 microM), and Kfc was estimated at baseline and after 30 min of reperfusion. (1) Inhaled NO attenuated I/R-induced increases in Kfc. (2) Cell counts were similar at baseline. After 75 min of reperfusion, lung neutrophil retention (myeloperoxidase activity) and decreased perfusate neutrophil counts were similar in all groups. (3) In contrast to ISO, INO did not reverse microvascular leak. (4) 8-bromoguanosine 3',5'-cyclic monophosphate (8-br-cGMP) prevented I/R-induced microvascular leak in ODQ-treated lungs, but INO was no longer effective. Inhaled NO attenuates I/R-induced pulmonary microvascular leak, which requires sGC activation and may involve a mechanism independent of inhibition of leukocyte-endothelial cell interactions. In addition, INO is ineffective in reversing I/R-induced microvascular leak.

  3. CONCHAS-SPRAY, Reactive Flows with Fuel Sprays

    International Nuclear Information System (INIS)

    Cloutman, L.D.; Dukowicz, J.K.; Ramshaw, J.D.; Amsden, A.A.

    2001-01-01

    Description of program or function: CONCHAS-SPRAY solves the equations of transient, multicomponent, chemically reactive fluid dynamics, together with those for the dynamics of an evaporating liquid spray. The program was developed with applications to internal combustion engines in mind. The formulation is spatially two-dimensional, and encompasses both planar and axisymmetric geometries. In the latter case, the flow is permitted to swirl about the axis of symmetry. CONCHAS-SPRAY is a time-marching, finite- difference program that uses a partially implicit numerical scheme. Spatial differences are formed with respect to a generalized two- dimensional mesh of arbitrary quadrilaterals whose corner locations are specified functions of time. This feature allows a Lagrangian, Eulerian, or mixed description, and is particularly useful for representing curved or moving boundary surfaces. Arbitrary numbers of species and chemical reactions are allowed. The latter are subdivided into kinetic and equilibrium reactions, which are treated by different algorithms. A turbulent law-of-the-wall boundary layer option is provided. CONCHAS-SPRAY calls a number of LANL system subroutines to display graphic or numerical information on microfiche. These routines are not included, but are described in the reference report. Several routines called from LINPACK and SLATEC1.0 are included

  4. Solution precursor plasma deposition of nanostructured ZnO coatings

    International Nuclear Information System (INIS)

    Tummala, Raghavender; Guduru, Ramesh K.; Mohanty, Pravansu S.

    2011-01-01

    Highlights: → The solution precursor route employed is an inexpensive process with capability to produce large scale coatings at fast rates on mass scale production. → It is highly capable of developing tailorable nanostructures. → This technique can be employed to spray the coatings on any kind of substrates including polymers. → The ZnO coatings developed via solution precursor plasma spray process have good electrical conductivity and reflectivity properties in spite of possessing large amount of particulate boundaries, porosity and nanostructured grains. -- Abstract: Zinc oxide (ZnO) is a wide band gap semiconducting material that has various applications including optical, electronic, biomedical and corrosion protection. It is usually synthesized via processing routes, such as vapor deposition techniques, sol-gel, spray pyrolysis and thermal spray of pre-synthesized ZnO powders. Cheaper and faster synthesis techniques are of technological importance due to increased demand in alternative energy applications. Here, we report synthesis of nanostructured ZnO coatings directly from a solution precursor in a single step using plasma spray technique. Nanostructured ZnO coatings were deposited from the solution precursor prepared using zinc acetate and water/isopropanol. An axial liquid atomizer was employed in a DC plasma spray torch to create fine droplets of precursor for faster thermal treatment in the plasma plume to form ZnO. Microstructures of coatings revealed ultrafine particulate agglomerates. X-ray diffraction confirmed polycrystalline nature and hexagonal Wurtzite crystal structure of the coatings. Transmission electron microscopy studies showed fine grains in the range of 10-40 nm. Observed optical transmittance (∼65-80%) and reflectivity (∼65-70%) in the visible spectrum, and electrical resistivity (48.5-50.1 mΩ cm) of ZnO coatings are attributed to ultrafine particulate morphology of the coatings.

  5. Solution precursor plasma deposition of nanostructured ZnO coatings

    Energy Technology Data Exchange (ETDEWEB)

    Tummala, Raghavender [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States); Guduru, Ramesh K., E-mail: rkguduru@umich.edu [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States); Mohanty, Pravansu S. [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States)

    2011-08-15

    Highlights: {yields} The solution precursor route employed is an inexpensive process with capability to produce large scale coatings at fast rates on mass scale production. {yields} It is highly capable of developing tailorable nanostructures. {yields} This technique can be employed to spray the coatings on any kind of substrates including polymers. {yields} The ZnO coatings developed via solution precursor plasma spray process have good electrical conductivity and reflectivity properties in spite of possessing large amount of particulate boundaries, porosity and nanostructured grains. -- Abstract: Zinc oxide (ZnO) is a wide band gap semiconducting material that has various applications including optical, electronic, biomedical and corrosion protection. It is usually synthesized via processing routes, such as vapor deposition techniques, sol-gel, spray pyrolysis and thermal spray of pre-synthesized ZnO powders. Cheaper and faster synthesis techniques are of technological importance due to increased demand in alternative energy applications. Here, we report synthesis of nanostructured ZnO coatings directly from a solution precursor in a single step using plasma spray technique. Nanostructured ZnO coatings were deposited from the solution precursor prepared using zinc acetate and water/isopropanol. An axial liquid atomizer was employed in a DC plasma spray torch to create fine droplets of precursor for faster thermal treatment in the plasma plume to form ZnO. Microstructures of coatings revealed ultrafine particulate agglomerates. X-ray diffraction confirmed polycrystalline nature and hexagonal Wurtzite crystal structure of the coatings. Transmission electron microscopy studies showed fine grains in the range of 10-40 nm. Observed optical transmittance ({approx}65-80%) and reflectivity ({approx}65-70%) in the visible spectrum, and electrical resistivity (48.5-50.1 m{Omega} cm) of ZnO coatings are attributed to ultrafine particulate morphology of the coatings.

  6. Acoustic leak detection in nuclear power plants

    International Nuclear Information System (INIS)

    McElroy, J.W.

    1986-01-01

    For several years now, utilities have been utilizing acoustic leak detection methods as an operating tool in their nuclear power stations. The purpose for using the leak detection system at the various stations vary from safety, ALARA, improved operations, preventive maintenance, or increased plant availability. This paper describes the various acoustic techniques and their application. The techniques are divided into three categories: specific component leakage, intersystem leakage, and pipe through-wall crack leakage. The paper addresses each category in terms of motivation to monitor, method of application and operation, and benefits to be gained. Current requirements are reviewed and analyzed with respect to the acoustic techniques. The paper shows how acoustic leak detection is one of the most effective leak detection tools available. 9 figures, 1 table

  7. Numerical modelling of fuel sprays

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, C.

    1999-06-01

    The way the fuel is introduced into the combustion chamber is one of the most important parameters for the power output and the generation of emissions in the combustion of liquid fuels. The interaction between the turbulent gas flow field and the liquid fuel droplets, the vaporisation of them and the mixing of the gaseous fuel with the ambient air that are vital parameters in the combustion process. The use of numerical calculations is an important tool to better understand these complex interacting phenomena. This thesis reports on the numerical modelling of fuel sprays in non-reacting cases using an own developed spray module. The spray module uses the stochastic parcel method to represent the spray. The module was made in such manner that it could by coupled with different gas flow solver. Results obtained from four different gas flow solvers are presented in the thesis, including the use of two different kinds of turbulence models. In the first part the spray module is coupled with a k-{eta} based 2-D cylindrical gas flow solver. A thorough sensitivity analysis was performed on the spray and gas flow solver parameters, such as grid size dependence and sensitivity to initial values of k-{eta}. The results of the spray module were also compared to results from other spray codes, e.g. the well known KIVA code. In the second part of this thesis the spray was injected into a turbulent and fully developed crossflow studied. The spray module was attached to a LES (Large Eddy Simulation) based flow solvers enabling the study of the complex structures and time dependent phenomena involved in spray in crossflows. It was found that the spray performs an oscillatory motion and that the Strouhal number in the wake was about 0.1. Different spray breakup models were evaluated by comparing with experimental results 66 refs, 56 figs

  8. Spray Foam Exterior Insulation with Stand-Off Furring

    Energy Technology Data Exchange (ETDEWEB)

    Herk, Anastasia [IBACOS, Inc., Pittsburgh, PA (United States); Baker, Richard [IBACOS, Inc., Pittsburgh, PA (United States); Prahl, Duncan [IBACOS, Inc., Pittsburgh, PA (United States)

    2014-03-01

    IBACOS, in collaboration with GreenHomes America, was contracted by the New York State Energy Research and Development Authority to research exterior wall insulation solutions. This research investigated cost-effective deep energy retrofit (DER) solutions for improving the building shell exterior while achieving a cost-reduction goal, including reduced labor costs to reach a 50/50 split between material and labor. The strategies included exterior wall insulation plus energy upgrades as needed in the attic, mechanical and ventilation systems, and basement band joist, walls, and floors. The work can be integrated with other home improvements such as siding or window replacement. This strategy minimizes physical connections to existing wall studs, encapsulates existing siding materials (including lead paint) with spray foam, and creates a vented rain screen assembly to promote drying. GreenHomes America applied construction details created by IBACOS to a test home. 2x4 framing members were attached to the wall at band joists and top plates using 'L' clips, with spray foam insulating the wall after framing was installed. Windows were installed simultaneously with the framing, including extension jambs. The use of clips in specific areas provided the best strength potential, and 'picture framing' the spray foam held the 2x4s in place. Short-term testing was performed at this house, with monitoring equipment installed for long-term testing. Testing measurements will be provided in a later report, as well as utility impact (before and after), costs (labor and materials), construction time, standard specifications, and analysis for the exterior wall insulation strategy.

  9. Spray Foam Exterior Insulation with Stand-Off Furring

    Energy Technology Data Exchange (ETDEWEB)

    Herk, Anatasia [IBACOS, Inc., Pittsburgh, PA (United States); Baker, Richard [IBACOS, Inc., Pittsburgh, PA (United States); Prahl, Duncan [IBACOS, Inc., Pittsburgh, PA (United States)

    2014-03-01

    IBACOS, in collaboration with GreenHomes America, was contracted by the New York State Energy Research and Development Authority to research exterior wall insulation solutions. This research investigated cost-effective deep energy retrofit (DER) solutions for improving the building shell exterior while achieving a cost-reduction goal, including reduced labor costs to reach a 50/50 split between material and labor. The strategies included exterior wall insulation plus energy upgrades as needed in the attic, mechanical and ventilation systems, and basement band joist, walls, and floors. The work can be integrated with other home improvements such as siding or window replacement. This strategy minimizes physical connections to existing wall studs, encapsulates existing siding materials (including lead paint) with spray foam, and creates a vented rain screen assembly to promote drying. GreenHomes America applied construction details created by IBACOS to a test home. 2x4 framing members were attached to the wall at band joists and top plates using "L" clips, with spray foam insulating the wall after framing was installed. Windows were installed simultaneously with the framing, including extension jambs. The use of clips in specific areas provided the best strength potential, and "picture framing" the spray foam held the 2x4s in place. Short-term testing was performed at this house, with monitoring equipment installed for long-term testing. Testing measurements will be provided in a later report, as well as utility impact (before and after), costs (labor and materials), construction time, standard specifications, and analysis for the exterior wall insulation strategy.

  10. Operational tank leak detection and minimization during retrieval

    International Nuclear Information System (INIS)

    Hertzel, J.S.

    1996-03-01

    This report evaluates the activities associated with the retrieval of wastes from the single-shell tanks proposed under the initial Single-Shell Tank Retrieval System. This report focuses on minimizing leakage during retrieval by using effective leak detection and mitigating actions. After reviewing the historical data available on single-shell leakage, and evaluating current leak detection technology, this report concludes that the only currently available leak detection method which can function within the most probable leakage range is the mass balance system. If utilized after each sluicing campaign, this method should allow detection at a leakage value well below the leakage value where significant health effects occur which is calculated for each tank. Furthermore, this report concludes that the planned sequence or sluicing activities will serve to further minimize the probability and volume of leaks by keeping liquid away from areas with the greatest potential for leaking. Finally, this report identifies a series of operational responses which when used in conjunction with the recommended sluicing sequence and leak detection methods will minimize worker exposure and environmental safety health risks

  11. Experimental simulation of low rate primary coolant leaks. For the case of vessel head penetrations affected by through wall cracking

    International Nuclear Information System (INIS)

    You, D.; Feron, D.; Turluer, G.

    2002-01-01

    An experimental simulation of primary coolant leaks was carried out to determine how the composition of the leaking liquid would change. The experiment used the EVA experimental setup, specially designed for quantitatively investigating concentration phenomena driven by evaporation. The test showed that the final composition, obtained from a solution representative of the primary coolant at the beginning of the cycle, is highly concentrated and slightly acid. The experimental results are compared with those obtained using the MULTEQ software. (authors)

  12. NOEL: a no-leak fusion blanket concept

    International Nuclear Information System (INIS)

    Powell, J.R.; Yu, W.S.; Fillo, J.A.; Horn, F.L.; Makowitz, H.

    1980-01-01

    Analysis and tests of a no-leak fusion blanket concept (NOEL-NO External Leak) are described. Coolant cannot leak into the plasma chamber even if large through-cracks develop in the first wall. Blanket modules contain a two-phase material, A, that is solid (several cm thick) on the inside of the module shell, and liquid in the interior. The solid layer is maintained by imbedded tubes carrying a coolant, B, below the freezing point of A. Most of the 14-MeV neutron energy is deposited as heat in the module interior. The thermal energy flow from the module interior to the shell keeps the interior liquid. Pressure on the liquid A interior is greater than the pressure on B, so that B cannot leak out if failures occur in coolant tubes. Liquid A cannot leak into the plasma chamber through first wall cracks because of the intervening frozen layer. The thermal hydraulics and neutronics of NOEL blankets have been investigated for various metallic (e.g., Li, Pb 2 , LiPb, Pb) and fused salt choices for material A

  13. Leak processing system for valve gland portion

    International Nuclear Information System (INIS)

    Nishino, Masami

    1990-01-01

    When a process fluid for a valve to be checked is at such a normal temperature as during reactor operation, leaked fluid can be detected depending on the temperature increase accompanying the leakage. However, detection is difficult if the temperature of the process fluid for the valve to be checked is low and, if leakage is detected after the reactor start-up, repair has to be applied after the shutdown of the plant. Then, gland leak is detected by detecting the pressure instead of the temperature in the pipeline system and the leak flow rate is calculated based on the pressure. As a result, leakage is detected irrespective of the temperature of the leaked fluid and, for instance, leakage can be detected even in a case where the temperature is not high as in the case of pressure proof test for the pressure vessel before start-up. It can contribute much to the improvement of the plant operation efficiency and can determine the leak flow rate at a high accuracy. (N.H.)

  14. Chemical evolution of leaked high-level liquid wastes in Hanford soils

    Energy Technology Data Exchange (ETDEWEB)

    NYMAN,MAY D.; KRUMHANSL,JAMES L.; ZHANG,PENGCHU; ANDERSON,HOWARD L.; NENOFF,TINA M.

    2000-05-19

    A number of Hanford tanks have leaked high level radioactive wastes (HLW) into the surrounding unconsolidated sediments. The disequilibrium between atmospheric C0{sub 2} or silica-rich soils and the highly caustic (pH > 13) fluids is a driving force for numerous reactions. Hazardous dissolved components such as {sup 133}Cs, {sup 79}Se, {sup 99}Tc may be adsorbed or sequestered by alteration phases, or released in the vadose zone for further transport by surface water. Additionally, it is likely that precipitation and alteration reactions will change the soil permeability and consequently the fluid flow path in the sediments. In order to ascertain the location and mobility/immobility of the radionuclides from leaked solutions within the vadose zone, the authors are currently studying the chemical reactions between: (1) tank simulant solutions and Hanford soil fill minerals; and (2) tank simulant solutions and C0{sub 2}. The authors are investigating soil-solution reactions at: (1) elevated temperatures (60--200 C) to simulate reactions which occur immediately adjacent a radiogenically heated tank; and (2) ambient temperature (25 C) to simulate reactions which take place further from the tanks. The authors studies show that reactions at elevated temperature result in dissolution of silicate minerals and precipitation of zeolitic phases. At 25 C, silicate dissolution is not significant except where smectite clays are involved. However, at this temperature CO{sub 2} uptake by the solution results in precipitation of Al(OH){sub 3} (bayerite). In these studies, radionuclide analogues (Cs, Se and Re--for Tc) were partially removed from the test solutions both during high-temperature fluid-soil interactions and during room temperature bayerite precipitation. Altered soils would permanently retain a fraction of the Cs but essentially all of the Se and Re would be released once the plume was past and normal groundwater came in contact with the contaminated soil. Bayerite

  15. Chemical evolution of leaked high-level liquid wastes in Hanford soils

    International Nuclear Information System (INIS)

    NYMAN, MAY D.; KRUMHANSL, JAMES L.; ZHANG, PENGCHU; ANDERSON, HOWARD L.; NENOFF, TINA M.

    2000-01-01

    A number of Hanford tanks have leaked high level radioactive wastes (HLW) into the surrounding unconsolidated sediments. The disequilibrium between atmospheric C0 2 or silica-rich soils and the highly caustic (pH > 13) fluids is a driving force for numerous reactions. Hazardous dissolved components such as 133 Cs, 79 Se, 99 Tc may be adsorbed or sequestered by alteration phases, or released in the vadose zone for further transport by surface water. Additionally, it is likely that precipitation and alteration reactions will change the soil permeability and consequently the fluid flow path in the sediments. In order to ascertain the location and mobility/immobility of the radionuclides from leaked solutions within the vadose zone, the authors are currently studying the chemical reactions between: (1) tank simulant solutions and Hanford soil fill minerals; and (2) tank simulant solutions and C0 2 . The authors are investigating soil-solution reactions at: (1) elevated temperatures (60--200 C) to simulate reactions which occur immediately adjacent a radiogenically heated tank; and (2) ambient temperature (25 C) to simulate reactions which take place further from the tanks. The authors studies show that reactions at elevated temperature result in dissolution of silicate minerals and precipitation of zeolitic phases. At 25 C, silicate dissolution is not significant except where smectite clays are involved. However, at this temperature CO 2 uptake by the solution results in precipitation of Al(OH) 3 (bayerite). In these studies, radionuclide analogues (Cs, Se and Re--for Tc) were partially removed from the test solutions both during high-temperature fluid-soil interactions and during room temperature bayerite precipitation. Altered soils would permanently retain a fraction of the Cs but essentially all of the Se and Re would be released once the plume was past and normal groundwater came in contact with the contaminated soil. Bayerite, however, will retain significant

  16. Reliability of leak detection systems in LWRs

    International Nuclear Information System (INIS)

    Kupperman, D.S.

    1986-10-01

    In this paper, NRC guidelines for leak detection will be reviewed, current practices described, potential safety-related problems discussed, and potential improvements in leak detection technology (with emphasis on acoustic methods) evaluated

  17. Microstructure and mechanical properties of plasma sprayed HA/YSZ/Ti-6Al-4V composite coatings.

    Science.gov (United States)

    Khor, K A; Gu, Y W; Pan, D; Cheang, P

    2004-08-01

    Plasma sprayed hydroxyapatite (HA) coatings on titanium alloy substrate have been used extensively due to their excellent biocompatibility and osteoconductivity. However, the erratic bond strength between HA and Ti alloy has raised concern over the long-term reliability of the implant. In this paper, HA/yttria stabilized zirconia (YSZ)/Ti-6Al-4V composite coatings that possess superior mechanical properties to conventional plasma sprayed HA coatings were developed. Ti-6Al-4V powders coated with fine YSZ and HA particles were prepared through a unique ceramic slurry mixing method. The so-formed composite powder was employed as feedstock for plasma spraying of the HA/YSZ/Ti-6Al-4V coatings. The influence of net plasma energy, plasma spray standoff distance, and post-spray heat treatment on microstructure, phase composition and mechanical properties were investigated. Results showed that coatings prepared with the optimum plasma sprayed condition showed a well-defined splat structure. HA/YSZ/Ti-6Al-4V solid solution was formed during plasma spraying which was beneficial for the improvement of mechanical properties. There was no evidence of Ti oxidation from the successful processing of YSZ and HA coated Ti-6Al-4V composite powders. Small amount of CaO apart from HA, ZrO(2) and Ti was present in the composite coatings. The microhardness, Young's modulus, fracture toughness, and bond strength increased significantly with the addition of YSZ. Post-spray heat treatment at 600 degrees C and 700 degrees C for up to 12h was found to further improve the mechanical properties of coatings. After the post-spray heat treatment, 17.6% increment in Young's modulus (E) and 16.3% increment in Vicker's hardness were achieved. The strengthening mechanisms of HA/YSZ/Ti-6Al-4V composite coatings were related to the dispersion strengthening by homogeneous distribution of YSZ particles in the matrix, the good mechanical properties of Ti-6Al-4V and the formation of solid solution among HA

  18. Thermal Arc Spray Overview

    Science.gov (United States)

    Hafiz Abd Malek, Muhamad; Hayati Saad, Nor; Kiyai Abas, Sunhaji; Mohd Shah, Noriyati

    2013-06-01

    Usage of protective coating for corrosion protection was on highly demand during the past decade; and thermal spray coating played a major part during that time. In recent years, the thermal arc spray coating becomes a popular coating. Many big players in oil and gas such as PETRONAS, EXXON MOBIL and SHELL in Malaysia tend to use the coating on steel structure as a corrosion protection. Further developments in coating processes, the devices, and raw materials have led to expansion of functional coatings and applications scope from conventional coating to specialized industries. It is widely used because of its ability to withstand high process temperature, offer advantages in efficiency, lower cost and acts as a corrosion protection. Previous research also indicated that the thermal arc spray offers better coating properties compared to other methods of spray. This paper reviews some critical area of thermal spray coating by discussing the process/parameter of thermal arc spray technology and quality control of coating. Coating performance against corrosion, wear and special characteristic of coating are also described. The field application of arc spray technology are demonstrated and reviewed.

  19. Thermal Arc Spray Overview

    International Nuclear Information System (INIS)

    Malek, Muhamad Hafiz Abd; Saad, Nor Hayati; Abas, Sunhaji Kiyai; Shah, Noriyati Mohd

    2013-01-01

    Usage of protective coating for corrosion protection was on highly demand during the past decade; and thermal spray coating played a major part during that time. In recent years, the thermal arc spray coating becomes a popular coating. Many big players in oil and gas such as PETRONAS, EXXON MOBIL and SHELL in Malaysia tend to use the coating on steel structure as a corrosion protection. Further developments in coating processes, the devices, and raw materials have led to expansion of functional coatings and applications scope from conventional coating to specialized industries. It is widely used because of its ability to withstand high process temperature, offer advantages in efficiency, lower cost and acts as a corrosion protection. Previous research also indicated that the thermal arc spray offers better coating properties compared to other methods of spray. This paper reviews some critical area of thermal spray coating by discussing the process/parameter of thermal arc spray technology and quality control of coating. Coating performance against corrosion, wear and special characteristic of coating are also described. The field application of arc spray technology are demonstrated and reviewed.

  20. Simulation of leaking fuel rods

    International Nuclear Information System (INIS)

    Hozer, Z.

    2006-01-01

    The behaviour of failed fuel rods includes several complex phenomena. The cladding failure initiates the release of fission product from the fuel and in case of large defect even urania grains can be released into the coolant. In steady state conditions an equilibrium - diffusion type - release is expected. During transients the release is driven by a convective type leaching mechanism. There are very few experimental data on leaking WWER fuel rods. For this reason the activity measurements at the nuclear power plants provide very important information. The evaluation of measured data can help in the estimation of failed fuel rod characteristics and the prediction of transient release dynamics in power plant transients. The paper deals with the simulation of leaking fuel rods under steady state and transient conditions and describes the following new results: 1) A new algorithm has been developed for the simulation of leaking fuel rods under steady state conditions and the specific parameters of the model for the Paks NPP has been determined; 2) The steady state model has been applied to calculation of leaking fuel characteristics using iodine and noble gas activity measurement data; 3) A new computational method has been developed for the simulation of leaking fuel rods under transient conditions and the specific parameters for the Paks NPP has been determined; 4) The transient model has been applied to the simulation of shutdown process at the Paks NPP and for the prediction of the time and magnitude of 123 I activity peak; 5) Using Paks NPP data a conservative value has been determined for the upper limit of the 123 I release from failed fuel rods during transients

  1. LEAK: A source term generator for evaluating release rates from leaking vessels

    International Nuclear Information System (INIS)

    Clinton, J.H.

    1994-01-01

    An interactive computer code for estimating the rate of release of any one of several materials from a leaking tank or broken pipe leading from a tank is presented. It is generally assumed that the material in the tank is liquid. Materials included in the data base are acetonitrile, ammonia, carbon tetrachloride, chlorine, chlorine trifluoride, fluorine, hydrogen fluoride, nitric acid, nitrogen tetroxide, sodium hydroxide, sulfur hexafluoride, sulfuric acid, and uranium hexafluoride. Materials that exist only as liquid and/or vapor over expected ranges of temperature and pressure can easily be added to the data base file. The Fortran source code for LEAK and the data file are included with this report

  2. Leak Detection Modeling and Simulation for Oil Pipeline with Artificial Intelligence Method

    OpenAIRE

    Sukarno, Pudjo; Sidarto, Kuntjoro Adji; Trisnobudi, Amoranto; Setyoadi, Delint Ira; Rohani, Nancy; Darmadi, Darmadi

    2007-01-01

    Leak detection is always interesting research topic, where leak location and leak rate are two pipeline leaking parameters that should be determined accurately to overcome pipe leaking problems. In this research those two parameters are investigated by developing transmission pipeline model and the leak detection model which is developed using Artificial Neural Network. The mathematical approach needs actual leak data to train the leak detection model, however such data could not be obtained ...

  3. Margins in high temperature leak-before-break assessments

    Energy Technology Data Exchange (ETDEWEB)

    Budden, P.J.; Hooton, D.G.

    1997-04-01

    Developments in the defect assessment procedure R6 to include high-temperature mechanisms in Leak-before-Break arguments are described. In particular, the effect of creep on the time available to detect a leak and on the crack opening area, and hence leak rate, is discussed. The competing influence of these two effects is emphasized by an example. The application to Leak-before-Break of the time-dependent failure assessment diagram approach for high temperature defect assessment is then outlined. The approach is shown to be of use in assessing the erosion of margins by creep.

  4. Margins in high temperature leak-before-break assessments

    International Nuclear Information System (INIS)

    Budden, P.J.; Hooton, D.G.

    1997-01-01

    Developments in the defect assessment procedure R6 to include high-temperature mechanisms in Leak-before-Break arguments are described. In particular, the effect of creep on the time available to detect a leak and on the crack opening area, and hence leak rate, is discussed. The competing influence of these two effects is emphasized by an example. The application to Leak-before-Break of the time-dependent failure assessment diagram approach for high temperature defect assessment is then outlined. The approach is shown to be of use in assessing the erosion of margins by creep

  5. Impinging jet spray formation using non-Newtonian liquids

    Science.gov (United States)

    Rodrigues, Neil S.

    Over the past two decades there has been a heightened interest in implementing gelled propellants for rocket propulsion, especially for hypergolic bi-propellants such as monomethylhydrazine (MMH) and nitrogen tetroxide oxidizer (NTO). Due to the very high level of toxicity of hypergolic liquid rocket propellants, increasing safety is an important area of need for continued space exploration and defense operations. Gelled propellants provide an attractive solution to meeting the requirements for safety, while also potentially improving performance. A gelling agent can be added to liquid propellants exhibiting Newtonian behavior to transform the liquid into a non-Newtonian fluid with some solid-like behavior, i.e. a gel. Non-Newtonian jet impingement is very different from its Newtonian counterpart in terms of fluid flow, atomization, and combustion. This is due to the added agents changing physical properties such as the bulk rheology (viscosity) and interfacial rheology (surface tension). Spray characterization of jet impingement with Newtonian liquids has been studied extensively in existing literature. However, there is a scarcity in literature of studies that consider the spray characterization of jet impingement with gelled propellants. This is a rather critical void since a major tradeoff of utilizing gelled propellants is the difficulty with atomization due to the increased effective viscosity. However, this difficulty can be overcome by using gels that exhibit shear-thinning behavior---viscosity decreases with increasing strain rate. Shear-thinning fluids are ideal because they have the distinct advantage of only flowing easily upon pressure. Thereby, greatly reducing the amount of propellant that could be accidentally leaked during both critical functions such as liftoff or engagement in the battlefield and regular tasks like refilling propellant tanks. This experimental work seeks to help resolve the scarcity in existing literature by providing drop size

  6. Steam leak detection in advance reactors via acoustics method

    International Nuclear Information System (INIS)

    Singh, Raj Kumar; Rao, A. Rama

    2011-01-01

    Highlights: → Steam leak detection system is developed to detect any leak inside the reactor vault. → The technique uses leak noise frequency spectrum for leak detection. → Testing of system and method to locate the leak is also developed and discussed in present paper. - Abstract: Prediction of LOCA (loss of coolant activity) plays very important role in safety of nuclear reactor. Coolant is responsible for heat transfer from fuel bundles. Loss of coolant is an accidental situation which requires immediate shut down of reactor. Fall in system pressure during LOCA is the trip parameter used for initiating automatic reactor shut down. However, in primary heat transport system operating in two phase regimes, detection of small break LOCA is not simple. Due to very slow leak rates, time for the fall of pressure is significantly slow. From reactor safety point of view, it is extremely important to find reliable and effective alternative for detecting slow pressure drop in case of small break LOCA. One such technique is the acoustic signal caused by LOCA in small breaks. In boiling water reactors whose primary heat transport is to be driven by natural circulation, small break LOCA detection is important. For prompt action on post small break LOCA, steam leak detection system is developed to detect any leak inside the reactor vault. The detection technique is reliable and plays a very important role in ensuring safety of the reactor. Methodology developed for steam leak detection is discussed in present paper. The methods to locate the leak is also developed and discussed in present paper which is based on analysis of the signal.

  7. Combined control of morphology and polymorph in spray drying of mannitol for dry powder inhalation

    Science.gov (United States)

    Lyu, Feng; Liu, Jing J.; Zhang, Yang; Wang, Xue Z.

    2017-06-01

    The morphology and polymorphism of mannitol particles were controlled during spray drying with the aim of improving the aerosolization properties of inhalable dry powders. The obtained microparticles were characterized using scanning electron microscopy, infrared spectroscopy, differential scanning calorimetry, powder X-ray diffraction and inhaler testing with a next generation impactor. Mannitol particles of varied α-mannitol content and surface roughness were prepared via spray drying by manipulating the concentration of NH4HCO3 in the feed solution. The bubbles produced by NH4HCO3 led to the formation of spheroid particles with a rough surface. Further, the fine particle fraction was increased by the rough surface of carriers and the high α-mannitol content. Inhalable dry powders with a 29.1 ± 2.4% fine particle fraction were obtained by spray-drying using 5% mannitol (w/v)/2% NH4HCO3 (w/v) as the feed solution, proving that this technique is an effective method to engineer particles for dry powder inhalation.

  8. USING THE ADAPTED DLP SYSTEM FOR BLOCKING INFORMATION LEAKS

    Directory of Open Access Journals (Sweden)

    T. A. Andryianava

    2017-01-01

    Full Text Available The importance of using the adapted DLP-system in the «Blocking» mode of leaking confidential information of the company is investigated. The scheme of interception of information security events in the «Copy» mode is given, the analysis of which reflects the main drawback of using this mode – the DLP-system works only with copies of confidential documents, while the originals were delivered to the recipient. Such cases inflict enormous damage on companies, so the transfer of critical information beyond the corporate network is unacceptable.A solution is proposed for transferring the operation of the DLP-system from the «Copy» mode to the «Blocking» mode. It is important that the operation of the DLP-system does not hinder the staff members from performing regular operations and does not hinder business processes. Therefore, it is mandatory to adapt the standard DLP-system to the specifics of the company’s activities. After that the transition of the adapted DLP-system to the «Blocking» mode is carried out.Developed: the transition procedure of the adapted DLP-system from the «Copy» mode to the «Blocking» mode, the scheme of the event capture by the DLP-system for the two modes. The main channels of data leaks were investigated, the main leaks were identified by the data type and by the transmission channel. The analysis of the DLP-system operation in the «Blocking» mode is performed.

  9. Production of porous titanate microspheres by spray-drying of sols

    International Nuclear Information System (INIS)

    Sizgek, E.; Bartlett, J.R.; Woolfrey, J.L.

    1992-01-01

    Porous, multi-component titanate microspheres (20 to 50 μm in diameter) have been produced on a 10 kg scale by spray-drying a precursor sol containing titania, zirconia and alumina, and calcining the resulting powders at 723 K. The mixed TiO 2 /ZrO 2 sols were produced by hydrolysing tetraisopropyltitanate and peptising the hydrolysate slurry with zirconyl nitrate solution. TiO 2 /ZrO 2 sols with oxide concentrations in excess of 900 g dm -3 were produced. These sols were subsequently mixed with dispersible δ-Al 2 O 3 to produce well-dispersed TiO 2 /ZrO 2 /Al 2 O 3 (TZA) sols. The rheology and degree of aggregation of the multi-component sols were controlled by the addition of Al(NO 3 ) 3 solution. At relatively low electrolyte concentrations, the sols exhibited Newtonian behaviour, and the viscosity increased with increasing addition of electrolyte. However, at higher electrolyte concentrations, the colloidal dispersions exhibited shear-thinning behaviour. Hollow spheres were produced by spray-drying well-dispersed sols. In contrast, 'solid' spheres were produced by using dilute Al(NO 3 ) 3 to produce partially-aggregated TZA sols, prior to spray-drying. Calcined microspheres produced from partially-aggregated sols had total porosities of ∼ 50 %, with average pore diameters of ∼ 8 nm. These particles exhibited a high sorption capacity for simulated High Level Nuclear Waste

  10. An algorithm for leak point detection of underground pipelines

    International Nuclear Information System (INIS)

    Lee, Young Sup; Yoon, Dong Jin

    2004-01-01

    Leak noise is a good source to identify the exact location of a leak point of underground water pipelines. Water leak generates broadband noise from a leak location and can be propagated to both directions of water pipes. However, the necessity of long-range detection of this leak location makes to identify low-frequency acoustic waves rather than high frequency ones. Acoustic wave propagation coupled with surrounding boundaries including cast iron pipes is theoretically analyzed and the wave velocity was confirmed with experiment. The leak locations were identified both by the acoustic emission (AE) method and the cross-correlation method. In a short-range distance, both the AE method and cross-correlation method are effective to detect leak position. However, the detection for a long-range distance required a lower frequency range accelerometers only because higher frequency waves were attenuated very quickly with the increase of propagation paths. Two algorithms for the cross-correlation function were suggested, and a long-range detection has been achieved at real underground water pipelines longer than 300 m.

  11. Spray freeze drying to produce a stable Delta(9)-tetrahydrocannabinol containing inulin-based solid dispersion powder suitable for inhalation

    NARCIS (Netherlands)

    van Drooge, Dirk-Jan; Hinrichs, Wouter L J; Dickhoff, Bastiaan H J; Elli, Marco N A; Visser, Marinella R; Zijlstra, Gerrit S; Frijlink, Henderik W

    2005-01-01

    The purpose of this study is to investigate whether spray freeze drying produces an inhalable solid dispersion powder in which Delta(9)-tetrahydrocannabinol (THC) is stabilised. Solutions of THC and inulin in a mixture of tertiary butanol (TBA) and water were spray freeze dried. Drug loads varied

  12. Acoustic leak detection in piping systems, 4

    International Nuclear Information System (INIS)

    Kitajima, Akira; Naohara, Nobuyuki; Aihara, Akihiko

    1983-01-01

    To monitor a high-pressure piping of nuclear power plants, a possibility of acoustic leak detection method has been experimentally studied in practical field tests and laboratory tests. Characteristics of background noise in field test and the results of experiment are summarized as follows: (1) The level of background noise in primary loop (PWR) was almost constant under actual plant operation. But it is possible that it rises at the condition of the pressure in primary loop. (2) Based on many experience of laboratory tests and practical field tests. The leak monitoring system for practical field was designed and developed. To improve the reliability, a judgment of leak on this system is used three factors of noise level, duration time of phenomena and frequency spectrum of noise signal emitted from the leak point. (author)

  13. Nano and microparticle engineering of water insoluble drugs using a novel spray-drying process.

    Science.gov (United States)

    Schafroth, Nina; Arpagaus, Cordin; Jadhav, Umesh Y; Makne, Sushil; Douroumis, Dennis

    2012-02-01

    In the current study nano and microparticle engineering of water insoluble drugs was conducted using a novel piezoelectric spray-drying approach. Cyclosporin A (CyA) and dexamethasone (DEX) were encapsulated in biodegradable poly(D,L-lactide-co-glycolide) (PLGA) grades of different molecular weights. Spray-drying studies carried out with the Nano Spray Dryer B-90 employed with piezoelectric driven actuator. The processing parameters including inlet temperature, spray mesh diameter, sample flow rate, spray rate, applied pressure and sample concentration were examined in order to optimize the particle size and the obtained yield. The process parameters and the solute concentration showed a profound effect on the particle engineering and the obtained product yield. The produced powder presented consistent and reproducible spherical particles with narrow particle size distribution. Cyclosporin was found to be molecularly dispersed while dexamethasone was in crystalline state within the PLGA nanoparticles. Further evaluation revealed excellent drug loading, encapsulation efficiency and production yield. In vitro studies demonstrated sustained release patterns for the active substances. This novel spray-drying process proved to be efficient for nano and microparticle engineering of water insoluble active substances. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Double Shell Tank AY-102 Radioactive Waste Leak Investigation

    International Nuclear Information System (INIS)

    Washenfelder, Dennis J.

    2014-01-01

    PowerPoint. The objectives of this presentation are to: Describe Effort to Determine Whether Tank AY-102 Leaked; Review Probable Causes of the Tank AY-102 Leak; and, Discuss Influence of Leak on Hanford's Double-Shell Tank Integrity Program

  15. Fuel rod leak detector

    International Nuclear Information System (INIS)

    Womack, R.E.

    1978-01-01

    A typical embodiment of the invention detects leaking fuel rods by means of a radiation detector that measures the concentration of xenon-133 ( 133 Xe) within each individual rod. A collimated detector that provides signals related to the energy of incident radiation is aligned with one of the ends of a fuel rod. A statistically significant sample of the gamma radiation (γ-rays) that characterize 133 Xe is accumulated through the detector. The data so accumulated indicates the presence of a concentration of 133 Xe appropriate to a sound fuel rod, or a significantly different concentration that reflects a leaking fuel rod

  16. Study on the Measurement of Valve Leak Rate Using Acoustic Emission Technology

    International Nuclear Information System (INIS)

    Lee, Sang-Guk; Park, Jong-Hyuck; Yoo, Keun-Bae; Lee, Sun-Ki; Hong, Sung-Yull

    2006-01-01

    This study is to estimate the feasibility of acoustic emission(AE) method for the internal leak from the valves. In this study, 4 inch ball water valve leak tests using three different leak path and various leak rates were performed in order to analyze AE properties when leaks arise in valve seat. As a result of leak test for specimens simulated valve seat, we conformed that leak sound amplitude increased in proportion to the increase of leak rate, and leak rates were plotted versus peak acoustic amplitudes recorded within those two narrow frequency bands on each spectrum plot. The resulting plots of leak rate versus peak AE amplitude were the primary basis for determining the feasibility of quantifying leak acoustically. The large amount of data attained also allowed a favorable investigation of the effects of different leak paths, leak rates, pressure differentials and AE sensors on the AE amplitude spectrum. From the experimental results, it was suggested that the AE method for monitoring of leak was feasible. This paper describes quantitative measurements of fluid valve leak rates by the analysis of AE. Experimental apparatus were fabricated to accept a variety of leaking water valves in order to determine what characteristics of AE signal change with leak rate. The data for each valve were generated by varying the leak rate and recording the time averaged amplitude of AE versus frequency. Leak rates were varied by modifying the valve seating surfaces in ways designed to simulate actual defects observed in service. Most of the data analysis involved plotting the leak rate versus signal amplitude at a specific frequency to determine how well the two variables correlate in terms of accuracy, resolution, and repeatability

  17. Influence of coating defects on the corrosion behavior of cold sprayed refractory metals

    International Nuclear Information System (INIS)

    Kumar, S.; Rao, A. Arjuna

    2017-01-01

    Highlights: • Long duration immersion tests reveal inhomogeneous weight losses. • The weight loss for different coatings are well corroborated with the coating defects. • Chemical and micro structural analysis elucidates the reason behind the in homogeneous performance of different type of cold sprayed coatings. • In cold sprayed titanium, formation of oxide along the inter-splat boundary hinders the aggressive attack of the medium. - Abstract: The defects in the cold sprayed coatings are critical in the case of corrosion performances of the coatings in aggressive conditions. To understand the influence of coating defects on corrosion, immersion tests have been carried out in HF solution for the cold sprayed and heat treated Titanium, Tantalum and Niobium coatings. Long duration immersion tests reveal inhomogeneous weight losses of the samples prepared at different heat treatment conditions. The weight loss for different coatings has been well corroborated with the coating defects and microstructures. Chemical and micro structural analysis elucidates the reason behind the inhomogeneous performance of different type of cold sprayed coatings in corrosion medium. In the case of cold sprayed titanium, formation of stable oxide along the inter-splat boundary hinders the aggressive attack of the corrosion medium which is not so in other cases.

  18. Hair spray poisoning

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002705.htm Hair spray poisoning To use the sharing features on this page, please enable JavaScript. Hair spray poisoning occurs when someone breathes in (inhales) ...

  19. Spray rolling aluminum alloy strip

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, Kevin M.; Delplanque, J.-P.; Johnson, S.B.; Lavernia, E.J.; Zhou, Y.; Lin, Y

    2004-10-10

    Spray rolling combines spray forming with twin-roll casting to process metal flat products. It consists of atomizing molten metal with a high velocity inert gas, cooling the resultant droplets in flight and directing the spray between mill rolls. In-flight convection heat transfer from atomized droplets teams with conductive cooling at the rolls to rapidly remove the alloy's latent heat. Hot deformation of the semi-solid material in the rolls results in fully consolidated, rapidly solidified product. While similar in some ways to twin-roll casting, spray rolling has the advantage of being able to process alloys with broad freezing ranges at high production rates. This paper describes the process and summarizes microstructure and tensile properties of spray-rolled 2124 and 7050 aluminum alloy strips. A Lagrangian/Eulerian poly-dispersed spray flight and deposition model is described that provides some insight into the development of the spray rolling process. This spray model follows droplets during flight toward the rolls, through impact and spreading, and includes oxide film formation and breakup when relevant.

  20. Acoustic leak detector in Monju steam generator

    International Nuclear Information System (INIS)

    Wachi, E.; Inoue, T.

    1990-01-01

    Acoustic leak detectors are equipped with the Monju steam generators for one of the R and D activities, which are the same type of the detectors developed in the PNC 50MW Steam Generator Test Facility. Although they are an additional leak detection system to the regular one in Monju SG, they would also detect the intermediate or large leaks of the SG tube failures. The extrapolation method of a background noise analysis is expected to be verified by Monju SG data. (author). 4 figs

  1. CT assessment of anastomotic bowel leak

    International Nuclear Information System (INIS)

    Power, N.; Atri, M.; Ryan, S.; Haddad, R.; Smith, A.

    2007-01-01

    Aim: To evaluate the predictors of clinically important gastrointestinal anastomotic leaks using multidetector computed tomography (CT). Subjects and methods: Ninety-nine patients, 73 with clinical suspicion of anastomotic bowel leak and 26 non-bowel surgery controls underwent CT to investigate postoperative sepsis. Fifty patients had undergone large bowel and 23 small bowel anastomoses. The time interval from surgery was 3-30 days (mean 10 ± 5.9 SD) for the anastomotic group and 3-40 days (mean 14 ± 11 SD) for the control group (p = 0.3). Two radiologists blinded to the final results reviewed the CT examinations in consensus and recorded the presence of peri-anastomotic air, fluid or combination of the two; distant loculated fluid or combination of fluid and air; free air or fluid; and intestinal contrast leak. Final diagnosis of clinically important anastomotic leak (CIAL) was confirmed at surgery or by chart review of predetermined clinical and laboratory criteria. Results: The prevalence of CIAL in the group undergoing CT was 31.5% (23/73). The CT examinations with documented leak were performed 5-28 (mean; 11.4 ± 6 SD) days after surgery. Nine patients required repeat operation, 10 percutaneous abscess drainage, two percutaneous drainage followed by surgery, and two prolonged antibiotic treatment and total parenteral nutrition (TPN). Of the CT features examined, only peri-anastomotic loculated fluid containing air was more frequently seen in the CIAL group as opposed to the no leak group (p = 0.04). There was no intestinal contrast leakage in this cohort. Free air was present up to 9 days and loculated air up to 26 days without CIAL. Conclusion: Most postoperative CT features overlap between patients with and without CIAL. The only feature seen statistically more frequently with CIAL is peri-anastomotic loculated fluid containing air

  2. CT assessment of anastomotic bowel leak

    Energy Technology Data Exchange (ETDEWEB)

    Power, N. [Department of Radiology, Sunnybrook Hospital, Toronto, Ontario M4N 3M5 (Canada); Atri, M. [Department of Radiology, Sunnybrook Hospital, Toronto, Ontario M4N 3M5 (Canada)]. E-mail: mostafa.atri@sw.ca; Ryan, S. [Department of Radiology, Sunnybrook Hospital, Toronto, Ontario M4N 3M5 (Canada); Haddad, R. [Department of Surgery, Sunnybrook Hospital, Toronto, Ontario M4N 3M5 (Canada); Smith, A. [Department of Surgery, Sunnybrook Hospital, Toronto, Ontario M4N 3M5 (Canada)

    2007-01-15

    Aim: To evaluate the predictors of clinically important gastrointestinal anastomotic leaks using multidetector computed tomography (CT). Subjects and methods: Ninety-nine patients, 73 with clinical suspicion of anastomotic bowel leak and 26 non-bowel surgery controls underwent CT to investigate postoperative sepsis. Fifty patients had undergone large bowel and 23 small bowel anastomoses. The time interval from surgery was 3-30 days (mean 10 {+-} 5.9 SD) for the anastomotic group and 3-40 days (mean 14 {+-} 11 SD) for the control group (p = 0.3). Two radiologists blinded to the final results reviewed the CT examinations in consensus and recorded the presence of peri-anastomotic air, fluid or combination of the two; distant loculated fluid or combination of fluid and air; free air or fluid; and intestinal contrast leak. Final diagnosis of clinically important anastomotic leak (CIAL) was confirmed at surgery or by chart review of predetermined clinical and laboratory criteria. Results: The prevalence of CIAL in the group undergoing CT was 31.5% (23/73). The CT examinations with documented leak were performed 5-28 (mean; 11.4 {+-} 6 SD) days after surgery. Nine patients required repeat operation, 10 percutaneous abscess drainage, two percutaneous drainage followed by surgery, and two prolonged antibiotic treatment and total parenteral nutrition (TPN). Of the CT features examined, only peri-anastomotic loculated fluid containing air was more frequently seen in the CIAL group as opposed to the no leak group (p = 0.04). There was no intestinal contrast leakage in this cohort. Free air was present up to 9 days and loculated air up to 26 days without CIAL. Conclusion: Most postoperative CT features overlap between patients with and without CIAL. The only feature seen statistically more frequently with CIAL is peri-anastomotic loculated fluid containing air.

  3. Experiences with leak rate calculations methods for LBB application

    Energy Technology Data Exchange (ETDEWEB)

    Grebner, H.; Kastner, W.; Hoefler, A.; Maussner, G. [and others

    1997-04-01

    In this paper, three leak rate computer programs for the application of leak before break analysis are described and compared. The programs are compared to each other and to results of an HDR Reactor experiment and two real crack cases. The programs analyzed are PIPELEAK, FLORA, and PICEP. Generally, the different leak rate models are in agreement. To obtain reasonable agreement between measured and calculated leak rates, it was necessary to also use data from detailed crack investigations.

  4. Experiences with leak rate calculations methods for LBB application

    International Nuclear Information System (INIS)

    Grebner, H.; Kastner, W.; Hoefler, A.; Maussner, G.

    1997-01-01

    In this paper, three leak rate computer programs for the application of leak before break analysis are described and compared. The programs are compared to each other and to results of an HDR Reactor experiment and two real crack cases. The programs analyzed are PIPELEAK, FLORA, and PICEP. Generally, the different leak rate models are in agreement. To obtain reasonable agreement between measured and calculated leak rates, it was necessary to also use data from detailed crack investigations

  5. Study on the Fluid Leak Diagnosis for Steam Valve in Power Plant

    International Nuclear Information System (INIS)

    Lee, Sang-Guk; Park, Jong-Hyuck; Yoo, Keun-Bae; Lee, Sun-Ki; Hong, Sung-Yull

    2006-01-01

    This study aims to estimate the applicability of acoustic emission(AE) method for the internal fluid leak from the valves. In this study, 4 inch gate steam valve leak tests were performed in order to analyze AE properties when leaks arise in valve seat. As a result of leak test for valve seat in a secondary system of power plant, we conformed that leak sound level increased in proportion to the increase of leak rate, and leak rates were compared to simulated tests. The resulting plots of leak rate versus peak frequency and AE signal level were the primary basis for determining the feasibility of quantifying leak acoustically. Previously, the large amount of data attained also allowed a favorable investigation of the effects of different leak paths, leak rates, pressure differentials through simulated test. All results of application tests are compared with results of simulated test. From the application tests, it was suggested that the AE method for diagnosis of steam leak was applicable. This paper presents quantitative measurements of fluid valve leak conditions by the analysis of AE parameter, FFT(fast fourier transform) and RMS(root mean square) level. Test apparatus were fabricated to accept a variety of leaking steam valves in order to determine what characteristics of AE signal change with leak conditions. The data for each valve were generated by varying the leak rate and recording the averaged RMS level versus time and frequency versus amplitude(FFT). Leak rates were varied by the valve differential pressure and valve size and leaking valves were observed in service. Most of the data analysis involved plotting the leak rate versus RMS level at a specific frequency to determine how well the two variables correlate in terms of accuracy, resolution, and repeatability

  6. Leak test fixture and method for using same

    Science.gov (United States)

    Hawk, Lawrence S.

    1976-01-01

    A method and apparatus are provided which are especially useful for leak testing seams such as an end closure or joint in an article. The test does not require an enclosed pressurized volume within the article or joint section to be leak checked. A flexible impervious membrane is disposed over an area of the seamed surfaces to be leak checked and sealed around the outer edges. A preselected vacuum is applied through an opening in the membrane to evacuate the area between the membrane and the surface being leak checked to essentially collapse the membrane to conform to the article surface or joined adjacent surfaces. A pressure differential is concentrated at the seam bounded by the membrane and only the seam experiences a pressure differential as air or helium molecules are drawn into the vacuum system through a leak in the seam. A helium detector may be placed in a vacuum exhaust line from the membrane to detect the helium. Alternatively, the vacuum system may be isolated at a preselected pressure and leaks may be detected by a subsequent pressure increase in the vacuum system.

  7. Remotely controlled spray gun

    Science.gov (United States)

    Cunningham, William C. (Inventor)

    1987-01-01

    A remotely controlled spray gun is described in which a nozzle and orifice plate are held in precise axial alignment by an alignment member, which in turn is held in alignment with the general outlet of the spray gun by insert. By this arrangement, the precise repeatability of spray patterns is insured.

  8. Spray layer-by-layer films based on phospholipid vesicles aiming sensing application via e-tongue system

    International Nuclear Information System (INIS)

    Aoki, P.H.B.; Volpati, D.; Cabrera, F.C.; Trombini, V.L.; Riul, A.; Constantino, C.J.L.

    2012-01-01

    The Layer-by-Layer (LbL) technique via spraying (spray-LbL) has been applied as new and alternative methodology to fabricate ultrathin films due to its versatility in relation to the conventional dipping-LbL method, mainly in terms of faster layer deposition and larger coated area. In this work, the possibility of immobilizing vesicles of dipalmitoyl phosphatidyl glycerol (DPPG) phospholipid onto alternating layers of the polyelectrolyte poly(allylamine hydrochloride) (PAH) using the spray-LbL method was investigated, being the results compared to the conventional dipping-LbL method. The growth of (PAH/DPPG) n spray-LbL films was systematically monitored by quartz crystal microbalance (QCM) and ultraviolet–visible (UV–vis) absorption spectroscopy, revealing a linear increase of the absorbance vs deposited layers. In relation to a possible electrostatic interaction between the groups PO 4 − (DPPG) and NH 3 + (PAH), it was observed through Fourier transform infrared (FTIR) absorption spectroscopy that the spectrum recorded for the spray-LbL film is basically a simple superposition of the FTIR spectra from PAH and DPPG casting films. The latter indicates a weak interaction between both materials, differently of the trend observed for (PAH/DPPG) n grown via dipping-LbL method. Atomic force microscopy (AFM) images of spray-LbL films showed evidences that the DPPG vesicles present in the aqueous dispersion are not destroyed when submitted to pressure conditions during the spray deposition. However, comparing to dipping-LbL, the DPPG vesicles do not cover completely the PAH layer for the spray-LbL film, which was further confirmed by surface-enhanced Raman scattering (SERS) measurements. Moreover, the AFM analysis showed that the spray-LbL deposition led to thicker PAH/DPPG bilayers in average than via dipping-LbL for the same concentrations of PAH solution and DPPG dispersion, which is consistent with QCM and UV–vis absorption results. PAH/DPPG films deposited by

  9. Operational Philosophy Concerning Manned Spacecraft Cabin Leaks

    Science.gov (United States)

    DeSimpelaere, Edward

    2011-01-01

    The last thirty years have seen the Space Shuttle as the prime United States spacecraft for manned spaceflight missions. Many lessons have been learned about spacecraft design and operation throughout these years. Over the next few decades, a large increase of manned spaceflight in the commercial sector is expected. This will result in the exposure of commercial crews and passengers to many of the same risks crews of the Space Shuttle have encountered. One of the more dire situations that can be encountered is the loss of pressure in the habitable volume of the spacecraft during on orbit operations. This is referred to as a cabin leak. This paper seeks to establish a general cabin leak response philosophy with the intent of educating future spacecraft designers and operators. After establishing a relative definition for a cabin leak, the paper covers general descriptions of detection equipment, detection methods, and general operational methods for management of a cabin leak. Subsequently, all these items are addressed from the perspective of the Space Shuttle Program, as this will be of the most value to future spacecraft due to similar operating profiles. Emphasis here is placed upon why and how these methods and philosophies have evolved to meet the Space Shuttle s needs. This includes the core ideas of: considerations of maintaining higher cabin pressures vs. lower cabin pressures, the pros and cons of a system designed to feed the leak with gas from pressurized tanks vs. using pressure suits to protect against lower cabin pressures, timeline and consumables constraints, re-entry considerations with leaks of unknown origin, and the impact the International Space Station (ISS) has had to the standard Space Shuttle cabin leak response philosophy. This last item in itself includes: procedural management differences, hardware considerations, additional capabilities due to the presence of the ISS and its resource, and ISS docking/undocking considerations with a

  10. Fibrin glue as agent for sealing corneal and conjunctival wound leaks.

    Science.gov (United States)

    Scalcione, C; Ortiz-Vaquerizas, D; Said, D G; Dua, H S

    2018-02-01

    PurposeTo describe a novel use of fibrin glue in managing leaking blebs and leaking wounds following trauma or surgery.MethodsInterventional case series.ResultsWe report eight patients, including three where intra-operative or immediate post-penetrating keratoplasty recalcitrant leaks from the graft-host junction and/or openings created by the needle pass, were noted. All three had thin recipient beds in the sector of leak. This was managed by intra-cameral injection of fibrin glue in the affected quadrant. This stopped the leak and allowed the defect to heal. One patient of Descemets-stripping-endothelial-keratoplasty had leak from the surgical wound, which was also sealed with fibrin glue. Two patients with leaking glaucoma-surgery-related blebs were treated with intra-bleb injection of fibrin glue to stop the leak. One patient with a penetrating corneal injury with a metal wire had a brisk leak upon removal of the wire. This was sealed with fibrin glue. Another patient of chemical burn with spontaneous leaks was managed by glue injection in the perforations. Transient rise of intraocular pressure in one patient with a leaking bleb was the only adverse event recorded.ConclusionThis novel adaptation of the application of fibrin glue can help to deal with persistent intra-operative, post-operative and traumatic aqueous and air leaks.

  11. Clinical Factors and Postoperative Impact of Bile Leak After Liver Resection.

    Science.gov (United States)

    Martin, Allison N; Narayanan, Sowmya; Turrentine, Florence E; Bauer, Todd W; Adams, Reid B; Stukenborg, George J; Zaydfudim, Victor M

    2018-04-01

    Despite technical advances, bile leak remains a significant complication after hepatectomy. The current study uses a targeted multi-institutional dataset to characterize perioperative factors that are associated with bile leakage after hepatectomy to better understand the impact of bile leak on morbidity and mortality. Adult patients in the 2014-2015 ACS NSQIP targeted hepatectomy dataset were linked to the ACS NSQIP PUF dataset. Bivariable and multivariable regression analyses were used to assess the associations between clinical factors and post-hepatectomy bile leak. Of 6859 patients, 530 (7.7%) had a postoperative bile leak. Proportion of bile leaks was significantly greater in patients after major compared to minor hepatectomy (12.6 vs. 5.1%, p leak was significantly greater in patients after major hepatectomy who had concomitant enterohepatic reconstruction (31.8 vs. 10.1%, p leaks (6.0 vs. 1.7%, p leak was independently associated with increased risk of postoperative morbidity (OR = 4.55; 95% CI 3.72-5.56; p leak was not independently associated with increased risk of postoperative mortality (p = 0.262). Major hepatectomy and enterohepatic biliary reconstruction are associated with significantly greater rates of bile leak after liver resection. Bile leak is independently associated with significant postoperative morbidity. Mitigation of bile leak is critical in reducing morbidity and mortality after liver resection.

  12. Steam generator leak detection at Bruce A Unit 1

    International Nuclear Information System (INIS)

    Maynard, K.J.; McInnes, D.E.; Singh, V.P.

    1997-01-01

    A new steam generator leak detection system was recently developed and utilized at Bruce A. The equipment is based on standard helium leak detection, with the addition of moisture detection and several other capability improvements. All but 1% of the Unit 1 Boiler 03 tubesheet was inspected, using a sniffer probe which inspected tubes seven at a time and followed by individual tube inspections. The leak search period was completed in approximately 24 hours, following a prerequisite period of several days. No helium leak indications were found anywhere on the boiler. A single water leak indication was found, which was subsequently confirmed as a through-wall defect by eddy current inspection. (author)

  13. ISOLDE Off-line Gas Leak Upgrade

    CERN Document Server

    Nielsen, Kristoffer Bested

    2017-01-01

    This study investigates gas injection system of the ISOLDE Off-line separator. A quadrupole mass spectrometer is used to analysis the composition of the gas. Based on these measurements a contamination of the injected gas is found and a system upgrade is purposed. Furthermore a calibration of the leak rate of the leak valve is made.

  14. Treatment of air leak in polytrauma patients with blunt chest injury.

    Science.gov (United States)

    Halat, Gabriel; Negrin, Lukas L; Chrysou, Konstantina; Hoksch, Beatrix; Schmid, Ralph A; Kocher, Gregor J

    2017-09-01

    Precise diagnostics and an adequate therapeutic approach are mandatory in the treatment of air leak in polytrauma patients with blunt chest trauma. The aim of this study was to evaluate the incidence, characteristics, and management of air leak following this injury pattern. Data from 110 polytrauma patients was collected retrospectively. Fifty-four patients received initial treatment by chest tube placement for pneumothorax. These patients were classified into two groups, one with severe air leak and one with minor air leak. An evaluation of injury pattern, chest wall injuries in particular, duration of air leak, reason for drainage maintenance in place, hospital length of stay, ICU stay, ventilator duration, type of treatment, and the delay to surgical intervention was performed. Whereas 4 patients showed severe air leak and were subsequently scheduled for timely surgical intervention, the remaining 50 patients only showed minor air leak. Only 7 patients with minor air leak suffered from prolonged air leak (>5days), which spontaneously resolved in all of them after a mean duration of 7.7days (range 6-12days). Absence of a prolonged air leak resulted in a shorter length of stay and a shorter duration of mechanical ventilation, although no statistical significance was observed. Early spontaneous cessation of most minor air leaks as well as early surgical intervention for severe air leak lead to very satisfactory patient outcomes with a relatively short hospital stay in our patients. We therefore advocate early surgery for lacerations of the pulmonary parenchyma resulting in severe air leak, whereas minor air leaks can usually be treated conservatively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Evaluation of leak rate by EPRI code

    International Nuclear Information System (INIS)

    Isozaki, Toshikuni; Hashiguchi, Issei; Kato, Kiyoshi; Miyazono, Shohachiro

    1987-08-01

    From 1987, a research on the leak rate from a cracked pipe under BWR or PWR operating condition is going to be carried out at the authors' laboratory. This report describes the computed results by EPRI's leak rate code which was mounted on JAERI FACOM-M380 machine. Henry's critical flow model is used in this program. For the planning of an experimental research, the leak rate from a crack under BWR or PWR operating condition is computed, varying a crack length 2c, crack opening diameter COD and pipe diameter. The COD value under which the minimum detectable leak rate of 5 gpm is given is 0.22 mm or 0.21 mm under the BWR or PWR condition with 2c = 100 mm and 16B pipe geometry. The entire lists are shown in the appendix. (author)

  16. Automated leak localization performance without detailed demand distribution data

    NARCIS (Netherlands)

    Moors, Janneke; Scholten, L.; van der Hoek, J.P.; den Besten, J.

    2018-01-01

    Automatic leak localization has been suggested to reduce the time and personnel efforts needed to localize
    (small) leaks. Yet, the available methods require a detailed demand distribution model for successful
    calibration and good leak localization performance. The main aim of this work was

  17. Air leak after lung resection: pathophysiology and patients' implications.

    Science.gov (United States)

    Pompili, Cecilia; Miserocchi, Giuseppe

    2016-02-01

    Protocols for the management of air leaks are critical aspects in the postoperative course of patients following lung resections. Many investigations in the last decade are focusing on the chest tube modalities or preventative measures, however, little is known about the pathophysiology of air leak and the patient perception of this common complication. This review concentrates on understanding the reasons why a pulmonary parenchyma may start to leak or an air leak may be longer than others. Experimental works support the notion that lung overdistension may favor air leak. These studies may represent the basis of future investigations. Furthermore, the standardization of nomenclature in the field of pleural space management and the creation of novel air leak scoring systems have contributed to improve the knowledge among thoracic surgeons and facilitate the organization of trials on this matter. We tried to summarize available evidences about the patient perception of a prolonged air leak and about what would be useful for them in order to prevent worsening of their quality of life. Future investigations are warranted to better understand the pathophysiologic mechanisms responsible of prolonged air leak in order to define tailored treatments and protocols. Improving the care at home with web-based telemonitoring or real time connected chest drainage may in a future improve the quality of life of the patients experience this complication and also enhance hospital finances.

  18. Presence of electrostatically adsorbed polysaccharides improves spray drying of liposomes.

    Science.gov (United States)

    Karadag, Ayse; Özçelik, Beraat; Sramek, Martin; Gibis, Monika; Kohlus, Reinhard; Weiss, Jochen

    2013-02-01

    functional components. However, maintaining their stability in aqueous dispersion represents a challenge for their commercialization. Spray drying may promise a solution to that problem. However, prior to this study spray drying of liposomes often led to the loss of structural integrity. Results of this study suggest that spray drying might be used to produce commercially feasible liposomal powders if proper combinations of adsorbing and nonadsorbing polymers are used in the liquid precursor system. © 2013 Institute of Food Technologists®

  19. Study on Leak Detection of the Pipeline System by Acoustic Emission

    International Nuclear Information System (INIS)

    Yoon, D. J.; Kim, C. J.

    1987-01-01

    Leak detection testing for the pipeline system was performed by the acoustic emission method. It was found that the detected signal spectrum was influenced by the frequency response of sensors and pressure changes. AE parameters and frequency spectrum distributions were used to analyze the leak signals. The slope rise time of AE parameters were the important factors for distinguishing leak signals. The amplitude of leak signal was more affected by the changes of leak, rate and pressure than those of leak type

  20. Comparision on dynamic behavior of diesel spray and rapeseed oil spray in diesel engine

    Science.gov (United States)

    Sapit, Azwan; Azahari Razali, Mohd; Faisal Hushim, Mohd; Jaat, Norrizam; Nizam Mohammad, Akmal; Khalid, Amir

    2017-04-01

    Fuel-air mixing is important process in diesel combustion. It significantly affects the combustion and emission of diesel engine. Biomass fuel has high viscosity and high distillation temperature and may negatively affect the fuel-air mixing process. Thus, study on the spray development and atomization of this type of fuel is important. This study investigates the atomization characteristics and droplet dynamic behaviors of diesel engine spray fuelled by rapeseed oil (RO) and comparison to diesel fuel (GO). Optical observation of RO spray was carried out using shadowgraph photography technique. Single nano-spark photography technique was used to study the characteristics of the spray while dual nano-spark shadowgraph technique was used to study the spray droplet behavior. Using in-house image processing algorithm, the images were processed and the boundary condition of each spray was also studied. The results show that RO has very poor atomization due to the high viscosity nature of the fuel when compared to GO. This is in agreement with the results from spray droplet dynamic behavior studies that shows due to the high viscosity, the RO spray droplets are large in size and travel downward, with very little influence of entrainment effect due to its large kinematic energy.

  1. Buried pipeline leak-detection technique and instruments using radioactive tracers

    International Nuclear Information System (INIS)

    Zhou Shuxuan; Lu Qingqian; Tang Yonghua

    1987-01-01

    For detecting and locating leaks on buried pipelines, a leak-detection technique and related instruments have been developed. Some quantity of fluid mixed with a radioactive tracer is injected. After the pipeline is cleaned, a leak-detector is put into and moves along the pipline to monitor the leaked radioactivity and to record both the radioactive signal and the time signal on a magnetic tape. From the signal curves, it can be judged whether there are any leaks on the pipeline and, if any, where they are

  2. Leak detection system for RBMK coolant circuit

    International Nuclear Information System (INIS)

    Cherkashov, Ju.M.; Strelkov, B.P.; Korolev, Yu.V.; Eperin, A.P.; Kozlov, E.P.; Belyanin, L.A.; Vanukov, V.N.

    1996-01-01

    In report the description of an object of the control is submitted, requests to control of leak-tightness and functioning of system are formulated, analysis of a current status on NPP with RBMK is submitted, review of methods of the leak-tightness monitoring, their advantage and defects with reference to conditions and features of a design RBMK is indicated, some results of tests and operation of various monitoring methods are submitted, requests on interaction of operative staff, leak-tightness monitoring system and protection system of reactor are submitted. (author). 11 figs, 1 tab

  3. Leak detection system for RBMK coolant circuit

    Energy Technology Data Exchange (ETDEWEB)

    Cherkashov, Ju M; Strelkov, B P; Korolev, Yu V; Eperin, A P; Kozlov, E P; Belyanin, L A; Vanukov, V N [Leningrad Nuclear Power Plant, Leningrad (Russian Federation). Research and Development Inst. of Power Engineering

    1997-12-31

    In report the description of an object of the control is submitted, requests to control of leak-tightness and functioning of system are formulated, analysis of a current status on NPP with RBMK is submitted, review of methods of the leak-tightness monitoring, their advantage and defects with reference to conditions and features of a design RBMK is indicated, some results of tests and operation of various monitoring methods are submitted, requests on interaction of operative staff, leak-tightness monitoring system and protection system of reactor are submitted. (author). 11 figs, 1 tab.

  4. Intelligence Leaks: What Is the Role of the Leak and the Leaker in U.S. Democracy?

    Science.gov (United States)

    2014-03-01

    WikiLeaks, the government did not fight a battle against the media due, in part, to the jurisprudence established by the Pentagon Papers . (The U.S...Accountability.” University of Georgia, School of Public and International Affairs, Occasional Paper . Johnson, Lyndon B. “Special Message to the Congress on...between the Pentagon Papers and WikiLeaks to Edward Snowden. 14. SUBJECT TERMS Bradley Manning, Daniel Ellsberg, executive

  5. Morphology, conductivity, and wetting characteristics of PEDOT:PSS thin films deposited by spin and spray coating

    Energy Technology Data Exchange (ETDEWEB)

    Zabihi, F.; Xie, Y.; Gao, S.; Eslamian, M., E-mail: Morteza.Eslamian@sjtu.edu.cn

    2015-05-30

    Highlights: • Nanostructure of spun-on and spray-on PEDOT:PSS thin films is studied. • A correlation is established between the film nanostructure and electrical conductivity. • Effect of process parameters is studied on the film characteristics. • A high solution concentration, high process temperature and multiple deposition layers are recommended. - Abstract: The goal of this paper is to study the characteristics of PEDOT:PSS thin films and the effects of varying the processing parameters on the structure, functionality, and surface wetting of spun-on and spray-on PEDOT:PSS thin films. PEDOT:PSS is a polymer mixture, which is electrically conductive and transparent and, therefore, is an attractive material for some optoelectronic applications, such as organic and perovskite solar cells. In this work, the films are fabricated using spin coating (a lab-scale method) and spray coating (an up-scalable method). The effects of spinning speed, drying time, and post-annealing temperature on spun-on samples and the effects of the substrate temperature and number of spray passes (deposition layers) on spray-on samples, as well as the effect of precursor solution concentration on both cases are investigated. Various characterization tools, such as AFM, SEM, XRD, confocal laser scanning microscopy (CLSM), and electrical conductivity measurements are used to determine the film roughness, thickness, structure, and morphology. The solution precursor physical data, such as contact angle on glass substrates, viscosity, and interfacial tension, are also obtained within a practical range of temperatures and concentrations. It is found that in both spin and spray coating routes, only well-controlled operating conditions result in the formation of conductive and defect-free PEDOT:PSS films. The formation of PEDOT:PSS thin films with small grains composed of PEDOT forming the core of the grains and PSS forming a shell or coating, which are evenly distributed in a PSS

  6. Morphology, conductivity, and wetting characteristics of PEDOT:PSS thin films deposited by spin and spray coating

    International Nuclear Information System (INIS)

    Zabihi, F.; Xie, Y.; Gao, S.; Eslamian, M.

    2015-01-01

    Highlights: • Nanostructure of spun-on and spray-on PEDOT:PSS thin films is studied. • A correlation is established between the film nanostructure and electrical conductivity. • Effect of process parameters is studied on the film characteristics. • A high solution concentration, high process temperature and multiple deposition layers are recommended. - Abstract: The goal of this paper is to study the characteristics of PEDOT:PSS thin films and the effects of varying the processing parameters on the structure, functionality, and surface wetting of spun-on and spray-on PEDOT:PSS thin films. PEDOT:PSS is a polymer mixture, which is electrically conductive and transparent and, therefore, is an attractive material for some optoelectronic applications, such as organic and perovskite solar cells. In this work, the films are fabricated using spin coating (a lab-scale method) and spray coating (an up-scalable method). The effects of spinning speed, drying time, and post-annealing temperature on spun-on samples and the effects of the substrate temperature and number of spray passes (deposition layers) on spray-on samples, as well as the effect of precursor solution concentration on both cases are investigated. Various characterization tools, such as AFM, SEM, XRD, confocal laser scanning microscopy (CLSM), and electrical conductivity measurements are used to determine the film roughness, thickness, structure, and morphology. The solution precursor physical data, such as contact angle on glass substrates, viscosity, and interfacial tension, are also obtained within a practical range of temperatures and concentrations. It is found that in both spin and spray coating routes, only well-controlled operating conditions result in the formation of conductive and defect-free PEDOT:PSS films. The formation of PEDOT:PSS thin films with small grains composed of PEDOT forming the core of the grains and PSS forming a shell or coating, which are evenly distributed in a PSS

  7. Spray sealing: A breakthrough in integral fuel tank sealing technology

    Science.gov (United States)

    Richardson, Martin D.; Zadarnowski, J. H.

    1989-11-01

    In a continuing effort to increase readiness, a new approach to sealing integral fuel tanks is being developed. The technique seals potential leak sources by spraying elastomeric materials inside the tank cavity. Laboratory evaluations project an increase in aircraft supportability and reliability, an improved maintainability, decreasing acquisition and life cycle costs. Increased usable fuel volume and lower weight than conventional bladders improve performance. Concept feasibility was demonstrated on sub-scale aircraft fuel tanks. Materials were selected by testing sprayable elastomers in a fuel tank environment. Chemical stability, mechanical properties, and dynamic durability of the elastomer are being evaluated at the laboratory level and in sub-scale and full scale aircraft component fatigue tests. The self sealing capability of sprayable materials is also under development. Ballistic tests show an improved aircraft survivability, due in part to the elastomer's mechanical properties and its ability to damp vibrations. New application equipment, system removal, and repair methods are being investigated.

  8. Thermal spray for commercial shipbuilding

    Science.gov (United States)

    Rogers, F. S.

    1997-09-01

    Thermal spraying of steel with aluminum to protect it from corrosion is a technology that has been proven to work in the marine environment. The thermal spray coating system includes a paint sealer that is applied over the thermally sprayed aluminum. This extends the service life of the coating and provides color to the end product. The thermal spray system protects steel both through the principle of isolation (as in painting) and galvanizing. With this dual protection mechanism, steel is protected from corrosion even when the coating is damaged. The thermal- sprayed aluminum coating system has proved the most cost- effective corrosion protection system for the marine environment. Until recently, however, the initial cost of application has limited its use for general application. Arc spray technology has reduced the application cost of thermal spraying of aluminum to below that of painting. Commercial shipbuilders could use this technology to enhance their market position in the marine industry.

  9. Management of vacuum leak-detection processes, calibration, and standards

    International Nuclear Information System (INIS)

    Wilson, N.G.

    1985-01-01

    Vacuum leak detection requires integrated management action to ensure the successful production of apparatus having required leak tightness. Implementation of properly planned, scheduled, and engineered procedures and test arrangements are an absolute necessity to prevent unexpected, impractical, technically inadequate, or unnecessarily costly incidents in leak-testing operations. The use of standard procedures, leak standards appropriate to the task, and accurate calibration systems or devices is necessary to validate the integrity of any leak-test procedure. In this paper, the need for implementing these practices is discussed using case histories of typical examples of large complex vacuum systems. Aggressive management practices are of primary importance throughout a project's life cycle to ensure the lowest cost; this includes successful leak testing of components. It should be noted that the opinions and conclusions expressed in this paper are those of the author and are not those of the Los Alamos National Laboratory or the Department of Energy

  10. Fluid pipeline leak detection and location with miniature RF tags

    Science.gov (United States)

    McIntyre, Timothy J.

    2017-05-16

    Sensors locate troublesome leaks in pipes or conduits that carry a flowing medium. These sensors, through tailored physical and geometric properties, preferentially seek conduit leaks or breaches due to flow streaming. The sensors can be queried via transceivers outside the conduit or located and interrogated inside by submersible unmanned vehicle to identify and characterize the nature of a leak. The sensors can be functionalized with other capabilities for additional leak and pipeline characterization if needed. Sensors can be recovered from a conduit flow stream and reused for future leak detection activities.

  11. Sealing of thermally-sprayed stainless steel coatings against corrosion using nickel electroplating technique

    Directory of Open Access Journals (Sweden)

    Hathaipat Koiprasert

    2007-07-01

    Full Text Available Electric arc spraying (EAS is one of the thermal spray techniques used for restoration and to providecorrosion resistance. It can be utilized to build up coatings to thicknesses of several millimeters, It is easy to use on-site. Most importantly, the cost of this technique is lower than other thermal spraying techniques thatmay be suitable for part restoration. A major disadvantage associated with the electric arc sprayed coating is its high porosity, which can be as high as 3-8% making it not appropriate for use in immersion condition. This work was carried out around the idea of using electroplating to seal off the pore of the EAS coating, with an aim to improve the corrosion resistance of the coating in immersion condition. This research compared the corrosion behavior of a stainless steel 316 electric arc sprayed coating in 2M NaOH solution at 25oC. It was found that the Ni plating used as sealant can improve the corrosion resistance of the EAS coating. Furthermore, the smoothened and plated stainless steel 316 coating has a better corrosion resistance than the plated EAS coating that was not ground to smoothen the surface before plating.

  12. Locating leaks in water mains using noise loggers

    OpenAIRE

    El-Abbasy, Mohammed S.; Mosleh, Fadi; Senouci, Ahmed; Zayed, Tarek; Al-Derham, Hassan

    2016-01-01

    Because of their potential danger to public health, economic loss, environmental damage, and energy waste, underground water pipelines leaks have received more attention globally. Researchers have proposed active leakage control approaches to localize, locate, and pinpoint leaks. Noise loggers have usually been used only for localizing leaks while other tools were used for locating and pinpointing. These approaches have resulted in additional cost and time. Thus, regression and artificial neu...

  13. Marine snow, organic solute plumes, and optimal chemosensory behavior of bacteria

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Jackson, G.A.

    2001-01-01

    Leaking organic solutes form an elongated plume in the wake of a sinking aggregate. These solutes may both be assimilated by suspended bacteria and guide bacteria with chemokinetic swimming behavior toward the aggregate. We used modifications of previously published models of the flow and concent......Leaking organic solutes form an elongated plume in the wake of a sinking aggregate. These solutes may both be assimilated by suspended bacteria and guide bacteria with chemokinetic swimming behavior toward the aggregate. We used modifications of previously published models of the flow...... behavior was used to examine the potential contribution of aggregate-generated solute plumes for water column bacteria] production. Despite occupying only a small volume fraction, the plumes may provide important growth habitats for free bacteria and account for a significant proportion of water column...

  14. Small leak shutdown, location, and behavior in LMFBR steam generators

    International Nuclear Information System (INIS)

    Sandusky, D.W.

    1976-01-01

    The paper summarizes an experimental study of small leaks tested under LMFBR steam generator conditions. Defected tubes were exposed to flowing sodium and steam. The observed behavior of the defected tubes is reported along with test results of shutdown methods. Leak location methods were investigated. Methods were identified to open plugged defects for helium leak testing and detect plugged leaks by nondestructive testing

  15. Plugging inaccessible leaks in cooling water pipework in nuclear power plants

    International Nuclear Information System (INIS)

    Powell, A.B.; May, R.; Down, M.G.

    1988-01-01

    The manifestation of initially small leaks in ancilliary reactor cooling water systems is not an unusual event. Often these leaks are in virtually inaccessible locations - for example, buried in thick concrete shielding or situated in cramped and highly radioactive vaults. Such leaks may ultimately prejudice the availability of the entire nuclear system. Continued operation without repair can result in the leak becoming larger, and the leaking water can cause further corrosion problems and interfere with instrumentation. In addition, the water may increase the volume of radwaste. In short, initially trivial leaks may cause significant operating problems. This paper describes the sealing of such leaks in the biological shield cooling system of Ontario Hydro's Pickering nuclear generating station CANDU reactors

  16. Ketorolac Tromethamine Spray Prevents Postendotracheal-Intubation-Induced Sore Throat after General Anesthesia

    Directory of Open Access Journals (Sweden)

    H. L. Yang

    2016-01-01

    Full Text Available Background. Postoperative sore throat is one of the major complaints of general anesthesia in the postanesthesia care unit. This prospective study investigated the preventive effect of ketorolac tromethamine spray in postendotracheal-intubation-induced sore throat after general anesthesia. Methods. Surgical patients undergoing general anesthesia with endotracheal intubation were recruited from a medical center. Patients were randomly assigned to group K (treated with 5% ketorolac tromethamine spray or group D (treated with distilled water spray. Before intubation, each endotracheal tube was sprayed with the appropriate solution by physicians over the 20 cm length of the cuff. Each group comprised 95 patients fitting the inclusion and exclusion criteria for whom complete data sets were collected. The intensity of the sore throat was measured at 1, 3, 6, and 24 h after surgery, and data were compared. Results. The two groups had similar characteristics. Postoperative sore throat was significantly less frequent in group K than in group D (p<0.001 and the pain intensity was significantly lower in group K than in group D at each time point (all p<0.001. Conclusions. This study demonstrated that preanesthesia 5% ketorolac tromethamine spray could effectively decrease postendotracheal-intubation-induced sore throat in patients undergoing general anesthesia.

  17. Measurement error in pressure-decay leak testing

    International Nuclear Information System (INIS)

    Robinson, J.N.

    1979-04-01

    The effect of measurement error in presssure-decay leak testing is considered, and examples are presented to demonstrate how it can be properly accomodated in analyzing data from such tests. Suggestions for more effective specification and conduct of leak tests are presented

  18. Capacitive system detects and locates fluid leaks

    Science.gov (United States)

    1966-01-01

    Electronic monitoring system automatically detects and locates minute leaks in seams of large fluid storage tanks and pipelines covered with thermal insulation. The system uses a capacitive tape-sensing element that is adhesively bonded over seams where fluid leaks are likely to occur.

  19. Electrostatically atomised hydrocarbon sprays

    Energy Technology Data Exchange (ETDEWEB)

    Yule, A.J.; Shrimpton, J.S.; Watkins, A.P.; Balachandran, W.; Hu, D. [UMIST, Manchester (United Kingdom). Thermofluids Division, Dept. of Mechanical Engineering

    1995-07-01

    A burner using an electrostatic method to produce and control a fuel spray is investigated for non-burning sprays. The burner has a charge injection nozzle and the liquid flow rate and charge injection rate are varied using hydrocarbon liquids of differing viscosities, surface tensions and electrical conductivities (kerosene, white spirit and diesel oil). Droplet size distributions are measured and it is shown how the dropsize, spray pattern, breakup mechanism and breakup length depend on the above variables, and in particular on the specific charge achieved in the spray. The data are valuable for validating two computer models under development. One predicts the electric field and flow field inside the nozzle as a function of emitter potential, geometry and flow rate. The other predicts the effect of charge on spray dispersion, with a view to optimizing spray combustion. It is shown that electrostatic disruptive forces can be used to atomize oils at flow rates commensurate with practical combustion systems and that the charge injection technique is particularly suitable for highly resistive liquids. Possible limitations requiring further research include the need to control the wide spray angle, which may provide fuel-air mixtures too lean near the nozzle, and the need to design for maximum charge injection rate, which is thought to be limited by corona breakdown in the gas near the nozzle orifice. 30 refs., 15 figs., 1 tab.

  20. Innovative Acoustic Sensor Technologies for Leak Detection in Challenging Pipe Types

    Science.gov (United States)

    2016-12-30

    the level of water leakage within the water distribution system. Table 7-3. Cost Summary for LeakFinderRT LeakFinderRT Leak Detection Cost...and to limit the drawdown of local water supplies. Implementation of improved leak detection technologies and the timely repair of water mains will...6-5. Water -filled Valve Box in Vicinity of Leak Detected by ZoneScan Alpha System

  1. The new CSA standard for leak detection

    Energy Technology Data Exchange (ETDEWEB)

    Pietsch, Ulli [TAU, Edmonton, Alberta, (Canada); Scott, Don [TransCanada Pipelines, Edmonton, Alberta, (Canada)

    2010-07-01

    Standards need to be updated regularly to reflect current technology and industry practices. This paper describes the new Canadian Standards Association (CSA) for leak detection called Recommended Practice for Liquid Hydrocarbon Pipeline System Leak Detection, Annex E, which can be found in the CSA Z662 Oil and Gas Pipeline Systems standard. The CSA formed a task force of industry experts and regulators for a period of 18 months to draft the new standards. Several comparisons were made with the American Petroleum Institute (API) recommended practice API 1130. This new version introduces and defines the terms, critical instrument, critical process and dependent instrument. The most significant improvement made by the new Annex E is the new requirement that an operating company must develop a leak detection strategy. The writing of a leak detection manual is given high priority. The use of both Annex E and API 1130 is recommended.

  2. Influence of spray parameters on the microstructure and mechanical properties of gas-tunnel plasma sprayed hydroxyapatite coatings

    International Nuclear Information System (INIS)

    Morks, M.F.; Kobayashi, Akira

    2007-01-01

    For biomedical applications, hydroxyapatite (HA) coatings were deposited on 304 stainless steel substrate by using a gas tunnel type plasma spraying process. The influences of spraying distances and plasma arc currents on the microstructure, hardness and adhesion properties of HA coatings were investigated. Microstructure observation by SEM showed that HA coatings sprayed at low plasma power have a porous structure and poor hardness. HA coatings sprayed at high plasma power and short spraying distance are characterized by good adhesion and low porosity with dense structure. Hardness increased for HA coatings sprayed at shorter spraying distance and higher plasma power, mainly due to the formation of dense coatings

  3. Accuracy improvement in the TDR-based localization of water leaks

    Directory of Open Access Journals (Sweden)

    Andrea Cataldo

    Full Text Available A time domain reflectometry (TDR-based system for the localization of water leaks has been recently developed by the authors. This system, which employs wire-like sensing elements to be installed along the underground pipes, has proven immune to the limitations that affect the traditional, acoustic leak-detection systems.Starting from the positive results obtained thus far, in this work, an improvement of this TDR-based system is proposed. More specifically, the possibility of employing a low-cost, water-absorbing sponge to be placed around the sensing element for enhancing the accuracy in the localization of the leak is addressed.To this purpose, laboratory experiments were carried out mimicking a water leakage condition, and two sensing elements (one embedded in a sponge and one without sponge were comparatively used to identify the position of the leak through TDR measurements. Results showed that, thanks to the water retention capability of the sponge (which maintains the leaked water more localized, the sensing element embedded in the sponge leads to a higher accuracy in the evaluation of the position of the leak. Keywords: Leak localization, TDR, Time domain reflectometry, Water leaks, Underground water pipes

  4. Estimating particle release through gas leaks in dry powder shipping containers

    International Nuclear Information System (INIS)

    Schwendiman, L.C.

    1977-06-01

    Information is presented from which an estimate can be made of the release of plutonium oxide from shipping containers. The leak diameter is estimated from gas leak tests of the container and an estimate is made of gas leak rate as a function of pressure over the time of interest in the accident. These calculations are limited in accuracy because of assumptions regarding leak geometry and the basic formulations of hydrodynamic flow for the assumed conditions. Sonic flow is assumed to be the limiting gas flow rate. Particles leaking from the air space above the powder will be limited by the low availability of particles due to rapid settling, the very limited driving force (pressure buildup) during the first minute, and the deposition in the leak channel. Equations are given to estimate deposition losses. Leaks of particles occurring below the level of the bulk powder will be limited by mechanical interference when leaks are of dimension smaller than particle sizes present. Some limiting cases can be calculated. When the leak dimension is large compared to the particle sizes present, maximum particle releases can be estimated, but will be very conservative. Further theoretical and experimental studies are needed to better define the hydrodynamics of gas flow in leaks of the size being considered, and to establish particle transport rates through known geometry leak paths

  5. Particle size distribution of aerosols sprayed from household hand-pump sprays containing fluorine-based and silicone-based compounds.

    Science.gov (United States)

    Kawakami, Tsuyoshi; Isama, Kazuo; Ikarashi, Yoshiaki

    2015-01-01

    Japan has published safety guideline on waterproof aerosol sprays. Furthermore, the Aerosol Industry Association of Japan has adopted voluntary regulations on waterproof aerosol sprays. Aerosol particles of diameter less than 10 µm are considered as "fine particles". In order to avoid acute lung injury, this size fraction should account for less than 0.6% of the sprayed aerosol particles. In contrast, the particle size distribution of aerosols released by hand-pump sprays containing fluorine-based or silicone-based compounds have not been investigated in Japan. Thus, the present study investigated the aerosol particle size distribution of 16 household hand-pump sprays. In 4 samples, the ratio of fine particles in aerosols exceeded 0.6%. This study confirmed that several hand-pump sprays available in the Japanese market can spray fine particles. Since the hand-pump sprays use water as a solvent and their ingredients may be more hydrophilic than those of aerosol sprays, the concepts related to the safety of aerosol-sprays do not apply to the hand pump sprays. Therefore, it may be required for the hand-pump spray to develop a suitable method for evaluating the toxicity and to establish the safety guideline.

  6. Environmental risk comparisons with internal methods of UST leak detection

    International Nuclear Information System (INIS)

    Durgin, P.B.

    1993-01-01

    The past five years have seen a variety of advances in how leaks can be detected from within underground storage tanks. Any leak-detection approach employed within a storage tanks must be conducted at specific time intervals and meet certain leak-rate criteria according to federal and state regulations. Nevertheless, the potential environmental consequences of leak detection approaches differ widely. Internal, volumetric UST monitoring techniques have developed over time including: (1) inventory control with stick measurements, (2) precision tank testing, (3) automatic tank gauging (ATG), (4) statistical inventory reconciliation (SIR), and (5) statistical techniques with automatic tank gauging. An ATG focuses on the advantage of precise data but measured for only a brief period. On the other hand, stick data has less precision but when combined with SIR over extended periods it too can detect low leak rates. Graphs demonstrate the comparable amounts of fuel than can leak out of a tank before being detected by these techniques. The results indicate that annual tank testing has the greatest potential for large volumes of fuel leaking without detection while new statistical approaches with an ATG have the least potential. The environmental implications of the volumes of fuel leaked prior to detection are site specific. For example, if storage tank is surrounded by a high water table and in a sole-source aquifer even small leaks may cause problems. The user must also consider regulatory risks. The level of environmental and regulatory risk should influence selection of the UST leak detection method

  7. Risk Factors for Gastrointestinal Leak after Bariatric Surgery: MBASQIP Analysis.

    Science.gov (United States)

    Alizadeh, Reza Fazl; Li, Shiri; Inaba, Colette; Penalosa, Patrick; Hinojosa, Marcelo W; Smith, Brian R; Stamos, Michael J; Nguyen, Ninh T

    2018-03-30

    Gastrointestinal leak remains one of the most dreaded complications in bariatric surgery. We aimed to evaluate risk factors and the impact of common perioperative interventions on the development of leak in patients who underwent laparoscopic bariatric surgery. Using the 2015 database of accredited centers, data were analyzed for patients who underwent laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass (LRYGB). Emergent, revisional, and converted cases were excluded. Multivariate logistic regression was used to analyze risk factors for leak, including provocative testing of anastomosis, surgical drain placement, and use of postoperative swallow study. Data from 133,478 patients who underwent laparoscopic sleeve gastrectomy (n = 92,495 [69.3%]) and LRYGB (n = 40,983 [30.7%]) were analyzed. Overall leak rate was 0.7% (938 of 133,478). Factors associated with increased risk for leak were oxygen dependency (adjusted odds ratio [AOR] 1.97), hypoalbuminemia (AOR 1.66), sleep apnea (AOR 1.52), hypertension (AOR 1.36), and diabetes (AOR 1.18). Compared with LRYGB, laparoscopic sleeve gastrectomy was associated with a lower risk of leak (AOR 0.52; 95% CI 0.44 to 0.61; p leak rate was higher in patients with vs without a provocative test (0.8% vs 0.4%, respectively; p leak rate was higher in patients with vs without a surgical drain placed (1.6% vs 0.4%, respectively; p leak rate was similar between patients with vs without swallow study (0.7% vs 0.7%; p = 0.50). The overall rate of gastrointestinal leak in bariatric surgery is low. Certain preoperative factors, procedural type (LRYGB), and interventions (intraoperative provocative test and surgical drain placement) were associated with a higher risk for leaks. Copyright © 2018 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Method of judging leak sources in a reactor container

    International Nuclear Information System (INIS)

    Maeda, Katsuji.

    1984-01-01

    Purpose: To enable exact judgement for leak sources upon leak accident in a reactor container of BWR type power plants as to whether the sources are present in the steam system or coolant system. Method: If leak is resulted from the main steam system, the hydrogen density in the reactor container is about 170 times as high as the same amount of leak from the reactor water. Accordingly, it can be judged whether the leak source is present in the steam system or reactor water system based on the change in the indication of hydrogen densitometer within the reactor container, and the indication from the drain amount from the sump in the container or the indication of a drain flow meter in the container dehumidifier. Further, I-131, Na-24 and the like as the radioactive nucleides in sump water of the container are measured to determine the density ratio R = (I-131)/(Na-24), and it is judged that the leak is resulted in nuclear water if the density ratio R is equal to that of reactor water and that the leak is resulted from the main steam or like other steam system if the density ratio R is higher than by about 100 times than that of reactor water. (Horiuchi, T.)

  9. Final evaluation of advanced and current leak detection systems

    International Nuclear Information System (INIS)

    Kupperman, D.S.; Carlson, R.; Brewer, W.; Lanham, R.

    1989-01-01

    This report presents the results of a study to evaluate the adequacy of leak detection systems in light water reactors. The sources of numerous reported leaks and methods of detection have been documented. Research to advance the state of the art of acoustic leak detection is presented, and procedures for implementation are discussed

  10. 10 CFR 39.35 - Leak testing of sealed sources.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Leak testing of sealed sources. 39.35 Section 39.35 Energy....35 Leak testing of sealed sources. (a) Testing and recordkeeping requirements. Each licensee who uses... record of leak test results in units of microcuries and retain the record for inspection by the...

  11. Sensors for Fluid Leak Detection

    Directory of Open Access Journals (Sweden)

    Gonzalo Pajares Martinsanz

    2015-02-01

    Full Text Available Fluid leak detection represents a problem that has attracted the interest of researchers, but not exclusively because in industries and services leaks are frequently common. Indeed, in water or gas supplies, chemical or thermal plants, sea-lines or cooling/heating systems leakage rates can cause important economic losses and sometimes, what it is more relevant, environmental pollution with human, animal or plant lives at risk. This last issue has led to increased national and international regulations with different degrees of severity regarding environmental conservation.[...

  12. Use of Trichoderma fungi in spray solutions to reduce Moniliophthora roreri infection of Theobroma cacao fruits in Northeastern Costa Rica.

    Science.gov (United States)

    Seng, John; Herrera, Geovanny; Vaughan, Christopher S; McCoy, Michael B

    2014-09-01

    Cacao (Theobroma cacao) is an important cash crop in tropical climates such as that of Latin America. Over the past several decades, the infection of cultivated cacao by Moniliophthllora roreri, known commonly as "monilia", has significantly hindered cacao production in Latin America. Studies have proposed the use of Trichoderma sp. fungi in biocontrol treatments to prevent and reduce monilia infection, yet tests of Trichoderma-containing spray treatments on cacao agroforests have produced mixed results. Researchers and agricultural workers have suggested that addition of soil, fly ash, or other carbon sources to a Trichoderma spray may improve its efficacy in fighting monilia. To test these suggestions, we designed a series of spray mixtures including Thichoderma cultures, soil, and all necessary controls. We applied the spray mixtures to 80 cacao trees (20 trees for each of four resistant-selected clones to monilia) at the FINMAC organic cacao plantation in Pueblo Nuevo de Guacimo, Limón Province, in northeastern Costa Rica in March-April 2013. Five treatments were applied (control, water, water plus sterilized soil, water plus Trichoderma, and water plus sterilized soil plus Trichoderma). Each treatment was applied to four trees of each clone. We monitored the incidence of monilia infection under each spray treatment over the course of 35d. We found that spraying entire cacao trees two times with a mixture containing Trichoderma and sterilized soil significantly reduced the incidence of monilia infection by 11% (p ≤ 0.05) in only 35d, as compared to the control. This reduction in loss of cacao pods translates into an increase of plantation mean productivity of 1,500 kg dried beans/ha by 198 kg/ha up to 1,698 kg/ha or by a total increase over the whole 110 ha plantation by 21,780 kg. We propose that using such an antifungal spray over the whole course of a crop cycle (120 days) would decrease infection incidence even more. Application of this fungal control

  13. Steam leak detection method in pipeline using histogram analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Se Oh; Jeon, Hyeong Seop; Son, Ki Sung; Chae, Gyung Sun [Saean Engineering Corp, Seoul (Korea, Republic of); Park, Jong Won [Dept. of Information Communications Engineering, Chungnam NationalUnversity, Daejeon (Korea, Republic of)

    2015-10-15

    Leak detection in a pipeline usually involves acoustic emission sensors such as contact type sensors. These contact type sensors pose difficulties for installation and cannot operate in areas having high temperature and radiation. Therefore, recently, many researchers have studied the leak detection phenomenon by using a camera. Leak detection by using a camera has the advantages of long distance monitoring and wide area surveillance. However, the conventional leak detection method by using difference images often mistakes the vibration of a structure for a leak. In this paper, we propose a method for steam leakage detection by using the moving average of difference images and histogram analysis. The proposed method can separate the leakage and the vibration of a structure. The working performance of the proposed method is verified by comparing with experimental results.

  14. Large-scale manufacture of ZnO nanorods by flame spray pyrolysis

    International Nuclear Information System (INIS)

    Hembram, K.; Sivaprakasam, D.; Rao, T. N.; Wegner, K.

    2013-01-01

    Large quantities of ZnO nanorods (>3 kg/h throughput) were produced in the gas-phase by flame spray pyrolysis (FSP) of a zinc nitrate–ethanol precursor solution without employing any catalysts or dopants. The nanorods with diameters of 20–30 nm and aspect ratios as high as seven were collected as a dry powder. Several rods self-aligned by forming junctions at the basal planes, while some even assembled into tetrapods. The aspect ratio of the nanorods could be controlled by the concentration of the Zn ions in the starting precursor solution, its delivery rate, and the oxygen flow into the reactor. To the best of our knowledge, this is the first time that synthesis of high aspect ratio ZnO nanorods by FSP is reported. Previous lab-scale experiments always yielded rather spherical albeit slightly elongated nanoparticles unless dopants were added. Such a product powder was obtained here when the ethanol in the precursor solution was replaced by methanol at otherwise constant process conditions. This is attributed to different temperature–time histories of the particles in the flame based on which a mechanism for ZnO nanorod formation in spray flames is proposed.

  15. Thermal decomposition of uranylnitrate by the Spray-Dryer process

    International Nuclear Information System (INIS)

    Wildhagen, G.R.S.; Silva, G.C. da

    1988-01-01

    The proposal of this work consist in the thermal decomposition of uranyl nitrate solutions by the Spray-Dryer process aiming the production of highly reactive fluidized UO 3 , adequate for the use in posterior of reduction to UO 2 and hydrofluorination to UF 4 , in a fluidized bed for the obtention of UF 6 in the cicle of nuclear fuels. (author) [pt

  16. Cable-Based Water Leak Detection Technology

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    Water leaks can be considered as a serious problem from many sources such as water supply and return chains, air conditioning units, cold-water chillers, clogged drains, damaged skylights or windows, or even construction errors. The new water leak detection technologies can provide significant advantages in cost, reliability, and easy adoption have continued since the traditional technology mainly focusing on a spot detector revealed several limitations.

  17. Autologous Blood Pleurodesis In Patients With Persistent Air Leaks

    Directory of Open Access Journals (Sweden)

    Agkajanzadeh M

    2003-10-01

    Full Text Available Persistent air leaks occur after Spontaneous pneumothorax both primary and secondary, and after lungs trauma and lung surgeries are sever problems encountered chest surgeons with. Persistent air leak causes longer patients hospitalization."nMaterials and Methods: We used autologous blood pleurodesis in patients with persistent air leak for 30patients with more than 8 days air leaks, during a three years period 1377-1380 (1999-2002."nResults: The patients had 19 years up to 70 years old. Eight patients had thoracotomy and lobectomy and /or segmentectomies 6 with primary pneumothorax, 10 with secondary pneumothorax, and four with penetrated or blunt thoracic traumas. Blood was obtained from femoral or brachial veins and 70-150 mis. Injected in chest tubes. Chest bottle was first lied 80cm higher than body levels. After 24 hours repositioned in normal levels, and patients were supervised. Via chest tube we injected blood 70-100ml.for young patients, and 100-150 ml for older patients into intra pleural space. There were no clamped chest tubes. There were no pain, respiratory distress, fever, or cough in pleurodesized patients. The only patient's complaint was local pain in femoral vein or brachial vein because blood sampling and blood obtaining, although there was no local visible complication as hematoma or bleeding. After 48 hours in 24 patients air leak ceased. In six patients because persistent air leak autologous blood pleurodesis repeated, two patients after 48hours"nair leak ceased, remaining four patients underwent for thoracotomies, success rate"nwas 86.6%."nConclusion: According above success rate we suggest autologous blood pleurodesis in patients with persistent air leak is a reliable, effective, and no complicated procedure for persistent air leaks.

  18. Acoustic leak detection at complicated topologies using neural netwoks

    International Nuclear Information System (INIS)

    Hessel, G.; Schmitt, W.; Weiss, F.P.

    1994-01-01

    Considering the shortcomings of all the existing leak detecting principles, a new method again based on the measurement of the leak induced sound but also applying pattern recognition is being developed. The capability of neural networks to localize leaks at the reactor pressure vessel (RPV) head of VVER-440 reactors is discussed. (orig./DG)

  19. FUZZY INFERENCE BASED LEAK ESTIMATION IN WATER PIPELINES SYSTEM

    Directory of Open Access Journals (Sweden)

    N. Lavanya

    2015-01-01

    Full Text Available Pipeline networks are the most widely used mode for transporting fluids and gases around the world. Leakage in this pipeline causes harmful effects when the flowing fluid/gas is hazardous. Hence the detection of leak becomes essential to avoid/minimize such undesirable effects. This paper presents the leak detection by spectral analysis methods in a laboratory pipeline system. Transient in the pressure signal in the pipeline is created by opening and closing the exit valve. These pressure variations are captured and power spectrum is obtained by using Fast Fourier Transform (FFT method and Filter Diagonalization Method (FDM. The leaks at various positions are simulated and located using these methods and the results are compared. In order to determine the quantity of leak a 2 × 1 fuzzy inference system is created using the upstream and downstream pressure as input and the leak size as the output. Thus a complete leak detection, localization and quantification are done by using only the pressure variations in the pipeline.

  20. Helium leak testing the Westinghouse LCP coil

    International Nuclear Information System (INIS)

    Merritt, P.A.; Attaar, M.H.; Hordubay, T.D.

    1983-01-01

    The tests, equipment, and techniques used to check the Westinghouse LCP coil for coolant flow path integrity and helium leakage are unique in terms of test sensitivity and application. This paper will discuss the various types of helium leak testing done on the LCP coil as it enters different stages of manufacture. The emphasis will be on the degree of test sensitivity achieved under shop conditions, and what equipment, techniques and tooling are required to achieve this sensitivity (5.9 x 10 -8 scc/sec). Other topics that will be discussed are helium flow and pressure drop testing which is used to detect any restrictions in the flow paths, and the LCP final acceptance test which is the final leak test performed on the coil prior to its being sent for testing. The overall allowable leak rate for this coil is 5 x 10 -6 scc/sec. A general evaluation of helium leak testing experience are included

  1. Role of non-destructive examinations in leak testing of glove boxes for industrial scale plutonium handling at nuclear fuel fabrication facility along with case study

    International Nuclear Information System (INIS)

    Aher, Sachin

    2015-01-01

    Non Destructive Examinations has the prominent role at Nuclear Fuel Fabrication Facilities. Specifically NDE has contributed at utmost stratum in Leak Testing of Glove Boxes and qualifying them as a Class-I confinement for safe Plutonium handling at industrial scale. Advanced Fuel Fabrication Facility, BARC, Tarapur is engaged in fabrication of Plutonium based MOX (PuO 2 , DDUO 2 ) fuel with different enrichments for first core of PFBR reactor. Alpha- Leak Tight Glove Boxes along with HEPA Filters and dynamic ventilation form the promising engineering system for safe and reliable handling of plutonium bearing materials considering the radiotoxicity and risk associated with handling of plutonium. Leak Testing of Glove Boxes which involves the leak detection, leak rectification and leak quantifications is major challenging task. To accomplish this challenge, various Non Destructive Testing methods have assisted in promising way to achieve the stringent leak rate criterion for commissioning of Glove Box facilities for plutonium handling. This paper highlights the Role of various NDE techniques like Soap Solution Test, Argon Sniffer Test, Pressure Drop/Rise Test etc. in Glove Box Leak Testing along with procedure and methodology for effective rectification of leakage points. A Flow Chart consisting of Glove Box leak testing procedure starting from preliminary stage up to qualification stage along with a case study and observations are discussed in this paper. (author)

  2. An experimental methodology to quantify the spray cooling event at intermittent spray impact

    International Nuclear Information System (INIS)

    Moreira, Antonio L.N.; Carvalho, Joao; Panao, Miguel R.O.

    2007-01-01

    The present paper describes an experimental methodology devised to study spray cooling with multiple-intermittent sprays as those found in fuel injection systems of spark-ignition and diesel engines, or in dermatologic surgery applications. The spray characteristics and the surface thermal behaviour are measured by combining a two-component phase-Doppler anemometer with fast response surface thermocouples. The hardware allows simultaneous acquisition of Doppler and thermocouple signals which are processed in Matlab to estimate the time-varying heat flux and fluid-dynamic characteristics of the spray during impact. The time resolution of the acquisition system is limited by the data rate of validation of the phase-Doppler anemometer, but it has been shown to be accurate for the characterization of spray-cooling processes with short spurt durations for which the transient period of spray injection plays an important role. The measurements are processed in terms of the instantaneous heat fluxes, from which phase-average values of the boiling curves are obtained. Two of the characteristic parameters used in the thermal analysis of stationary spray cooling events, the critical heat flux (CHF) and Leidenfrost phenomenon, are then inferred in terms of operating conditions of the multiple-intermittent injections, such as the frequency, duration and pressure of injection. An integral method is suggested to describe the overall process of heat transfer, which accounts for the fluid-dynamic heterogeneities induced by multiple and successive droplet interactions within the area of spray impact. The method considers overall boiling curves dependant on the injection conditions and provides an empirical tool to characterize the heat transfer processes on the impact of multiple-intermittent sprays. The methodology is tested in a preliminary study of the effect of injection conditions on the heat removed by a fuel spray striking the back surface of the intake valve as in spark

  3. Telescope sipping the optimum fuel leak detection system

    International Nuclear Information System (INIS)

    Deleryd, R.

    1998-01-01

    The TELESCOPE Sipping technology is an evolutionary development from previous ABB fuel leak systems used in LWR reactors. The system utilizes the existing dynamics that cause numerous fission products to leak from a failed fuel rod when the fuel assembly is raised from a reactor core during core fuel alterations. The system can also be used by repair work in pool side inspection in order to detect leaking rods or to verify reconstituted assemblies as non leakers. (author)

  4. Scalable organic solvent free supercritical fluid spray drying process for producing dry protein formulations.

    Science.gov (United States)

    Nuchuchua, O; Every, H A; Hofland, G W; Jiskoot, W

    2014-11-01

    In this study, we evaluated the influence of supercritical carbon dioxide (scCO2) spray drying conditions, in the absence of organic solvent, on the ability to produce dry protein/trehalose formulations at 1:10 and 1:4 (w/w) ratios. When using a 4L drying vessel, we found that decreasing the solution flow rate and solution volume, or increasing the scCO2 flow rate resulted in a significant reduction in the residual water content in dried products (Karl Fischer titration). The best conditions were then used to evaluate the ability to scale the scCO2 spray drying process from 4L to 10L chamber. The ratio of scCO2 and solution flow rate was kept constant. The products on both scales exhibited similar residual moisture contents, particle morphologies (SEM), and glass transition temperatures (DSC). After reconstitution, the lysozyme activity (enzymatic assay) and structure (circular dichroism, HP-SEC) were fully preserved, but the sub-visible particle content was slightly increased (flow imaging microscopy, nanoparticle tracking analysis). Furthermore, the drying condition was applicable to other proteins resulting in products of similar quality as the lysozyme formulations. In conclusion, we established scCO2 spray drying processing conditions for protein formulations without an organic solvent that holds promise for the industrial production of dry protein formulations. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Corrosion Resistance Properties of Aluminum Coating Applied by Arc Thermal Metal Spray in SAE J2334 Solution with Exposure Periods

    Directory of Open Access Journals (Sweden)

    Han-Seung Lee

    2016-03-01

    Full Text Available Arc thermal metal spray coating provides excellent corrosion, erosion and wear resistance to steel substrates. This paper incorporates some results of aluminum coating applied by this method on plain carbon steel. Thereafter, coated panels were exposed to an environment known to form stable corrosion products with aluminum. The coated panels were immersed in Society of Automotive Engineers (SAE J2334 for different periods of time. This solution consists of an aqueous solution of NaCl, CaCl2 and NaHCO3. Various electrochemical techniques, i.e., corrosion potential-time, electrochemical impedance spectroscopy (EIS and the potentiodynamic were used to determine the performance of stimulants in improving the properties of the coating. EIS studies revealed the kinetics and mechanism of corrosion and potentiodynamic attributed the formation of a passive film, which stifles the penetration of aggressive ions towards the substrate. The corrosion products that formed on the coating surface, identified using Raman spectroscopy, were Dawsonite (NaAlCO3(OH2 and Al(OH3. These compounds of aluminum are very sparingly soluble in aqueous solution and protect the substrate from pitting and uniform corrosion. The morphology and composition of corrosion products determined by scanning electron microscopy and energy dispersive X-ray analyses indicated that the environment plays a decisive role in improving the corrosion resistance of aluminum coating.

  6. Remote leak detection for the TFTR

    International Nuclear Information System (INIS)

    Walthers, C.R.

    1977-01-01

    The planned design for the TFTR (TOKAMAK Fusion Test Reactor) remote leak detection system consists of a central console which controls the application of tracer gas to possible leak areas. Seals are tested by admitting tracer gas to machined cavities on the atmospheric side of the seal. The tracer gas is brought to the seal cavity by 1 / 8 -inch diameter tubes which connect to local tracer gas/vacuum manifolds located outside the protective radiation shielding. Vacuum shell walls and welds are checked by flowing tracer gas through annular heating/cooling passages. The detector will be either an MSLD (mass spectrometer leak detector) or an RGA (residual gas analyzer), the location of which is not finalized. Feasibility tests performed and planned include response and sensitivity measurements of possible tubing/detector configurations with several tracer gases

  7. SR Ca2+-leak and disordered excitation-contraction coupling as the basis for arrhythmogenic and negative inotropic effects of acute ethanol exposure.

    Science.gov (United States)

    Mustroph, Julian; Wagemann, Olivia; Lebek, Simon; Tarnowski, Daniel; Ackermann, Jasmin; Drzymalski, Marzena; Pabel, Steffen; Schmid, Christof; Wagner, Stefan; Sossalla, Samuel; Maier, Lars S; Neef, Stefan

    2018-03-01

    Ethanol has acute negative inotropic and arrhythmogenic effects. The underlying mechanisms, however, are largely unknown. Sarcoplasmic reticulum Ca 2+ -leak is an important mechanism for reduced contractility and arrhythmias. Ca 2+ -leak can be induced by oxidative stress and Ca 2+ /Calmodulin-dependent protein kinase II (CaMKII). Therefore, we investigated the influence of acute ethanol exposure on excitation-contraction coupling in atrial and ventricular cardiomyocytes. Isolated human atrial and murine atrial or ventricular cardiomyocytes were preincubated for 30 min and then superfused with control solution or solution containing ethanol. Ethanol had acute negative inotropic and positive lusitropic effects in human atrial muscle strips and murine ventricular cardiomyocytes. Accordingly, Ca 2+ -imaging indicated lower Ca 2+ -transient amplitudes and increased SERCA2a activity, while myofilament Ca 2+ -sensitivity was reduced. SR Ca 2+ -leak was assessed by measuring Ca 2+ -sparks. Ethanol induced severe SR Ca 2+ -leak in human atrial cardiomyocytes (calculated leak: 4.60 ± 0.45 mF/F 0 vs 1.86 ± 0.26 in control, n ≥ 80). This effect was dose-dependent, while spontaneous arrhythmogenic Ca 2+ -waves increased ~5-fold, as investigated in murine cardiomyocytes. Delayed afterdepolarizations, which can result from increased SR Ca 2+ -leak, were significantly increased by ethanol. Measurements using the reactive oxygen species (ROS) sensor CM-H 2 DCFDA showed increased ROS-stress in ethanol treated cells. ROS-scavenging with N-acetylcysteine prevented negative inotropic and positive lusitropic effects in human muscle strips. Ethanol-induced Ca 2+ -leak was abolished in mice with knockout of NOX2 (the main source for ROS in cardiomyocytes). Importantly, mice with oxidation-resistant CaMKII (Met281/282Val mutation) were protected from ethanol-induced Ca 2+ -leak. We show for the first time that ethanol acutely induces strong SR Ca 2+ -leak, also altering

  8. Rio Vista gas leak study: Belleaire Gas Field, California

    International Nuclear Information System (INIS)

    Wilkey, P.L.

    1992-08-01

    The Rio Vista gas leak study evaluated methods for remotely sensing gas leaks from buried pipelines and developed methods to elucidate methane transport and microbial oxidation in soils. Remote-sensing methods were evaluated by singing gas leaks along an abandoned Pacific Gas and Electric (PG ampersand E) gas field collection line in northern California and applying surface-based and airborne remote-sensing techniques in the field, including thermal imaging, laser imaging, and multispectral imagery. The remote-sensing techniques exhibited limitations in range and in their ability to correlate with ground truth data. To elucidate methane transport and microbial oxidation in soils, a study of a controlled leak permitted field testing of methods so that such processes could be monitored and evaluated. Monitoring and evaluation techniques included (1) field measurement of soil-gas concentrations, temperatures, and pressures; (2) laboratory measurement of soil physical/chemical properties and activity of methane-oxidizing microorganisms by means of field samples; and (3) development of a preliminary numerical analysis technique for combined soil-gas transport/methane oxidation. Soil-gas concentrations at various depths responded rapidly to the high rate of gas leakage. The number of methane-oxidizing microorganisms in site soils rapidly increased when the gas leak was initiated and decreased after the leak was terminated. The preliminary field, laboratory, and numerical analysis techniques tested for this study of a controlled gas leak could be successfully applied to future studies of gas leaks. Because soil-gas movement is rapid and temporally variable, the use of several complementary techniques that permit generalization of site-specific results is favored

  9. The Influence of Nanodispersed Modifiers on the Structure and Properties of Plasma-Sprayed Coatings

    Directory of Open Access Journals (Sweden)

    Igor V. Smirnov

    2017-10-01

    Full Text Available Background. Currently, plasma-sprayed coatings are widely used to protect machine parts operating under conditions of high loads and temperatures, abrasive wear and exposure to corrosive media. Objective. The aim of the paper is to improve the physico-mechanical characteristics of plasma-sprayed coatings by modification of nano-sized particles of TiO2 oxides compounds. Methods. Experimental studies of corrosion resistance, microhardness, adhesion strength and residual stresses of plasma-sprayed coatings based on the oxide aluminum ceramic powder with the addition of nanodisperse TiO2 powder were conducted. Results. It is found that addition of TiO2 nanodisperse modifier to the oxide aluminum ceramic powder composition leads to corrosion resistance increase 2.8 times in a 10 % hydrochloric acid solution. The adhesive strength of ceramic nanomodified coatings is increased by 15–20 %. Conclusions. The positive influence of nanodispersed powders on the physico-mechanical and tribological characteristics of plasma-sprayed coatings is established.

  10. Effect of post annealing treatment on electrochromic properties of spray deposited niobium oxide thin films

    International Nuclear Information System (INIS)

    Mujawar, S.H.; Inamdar, A.I.; Betty, C.A.; Ganesan, V.; Patil, P.S.

    2007-01-01

    Niobium oxide thin films were deposited on the glass and fluorine doped tin oxide (FTO) coated glass substrates using simple and inexpensive spray pyrolysis technique. During deposition of the films various process parameters like nozzle to substrate distance, spray rate, concentration of sprayed solution were optimized to obtain well adherent and transparent films. The films prepared were further annealed and effect of post annealing on the structural, morphological, optical and electrochromic properties was studied. Structural and morphological characterizations of the films were carried out using scanning electron microscopy, atomic force microscopy and X-ray diffraction techniques. Electrochemical properties of the niobium oxide thin films were studied by using cyclic-voltammetry, chronoamperometry and chronocoulometry

  11. Superhydrophobic ceramic coating: Fabrication by solution precursor plasma spray and investigation of wetting behavior.

    Science.gov (United States)

    Xu, Pengyun; Coyle, Thomas W; Pershin, Larry; Mostaghimi, Javad

    2018-03-16

    Superhydrophobic surfaces are often created by fabricating suitable surface structures from low-surface-energy organic materials using processes that are not suitable for large-scale fabrication. Rare earth oxides (REO) exhibit hydrophobic behavior that is unusual among oxides. Solution precursor plasma spray (SPPS) deposition is a rapid, one-step process that can produce ceramic coatings with fine scale columnar structures. Manipulation of the structure of REO coatings through variation in deposition conditions may allow the wetting behavior to be controlled. Yb 2 O 3 coatings were fabricated via SPPS. Coating structure was investigated by scanning electron microscopy, digital optical microscopy, and x-ray diffraction. The static water contact angle and roll-off angle were measured, and the dynamic impact of water droplets on the coating surface recorded. Superhydrophobic behavior was observed; the best coating exhibited a water contact angle of ∼163°, a roll-off angle of ∼6°, and complete droplet rebound behavior. All coatings were crystalline Yb 2 O 3 , with a nano-scale roughness superimposed on a micron-scale columnar structure. The wetting behaviors of coatings deposited at different standoff distances were correlated with the coating microstructures and surface topographies. The self-cleaning, water flushing and water jetting tests were conducted and further demonstrated the excellent and durable hydrophobicity of the coatings. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Modifications Of A Commercial Spray Gun

    Science.gov (United States)

    Allen, Peter B.

    1993-01-01

    Commercial spray gun modified to increase spray rate and make sprayed coats more nearly uniform. Consists of gun head and pneumatic actuator. Actuator opens valves for two chemical components, called "A" and "B," that react to produce foam. Components flow through orifices, into mixing chamber in head. Mixture then flows through control orifice to spray tip. New spray tip tapered to reduce area available for accumulation of foam and makes tip easier to clean.

  13. Heat-Treated TiO2 Plasma Spray Deposition for Bioactivity Improvement in Ti-6Al-4V Alloy

    Science.gov (United States)

    Kumari, Renu; Majumdar, Jyotsna Dutta

    2017-12-01

    In the present study, titanium di-oxide (TiO2) coating has been developed on Ti-6Al-4V substrate by plasma spray deposition. Followed by plasma spraying, heat treatment of the sprayed sample has been carried out by isothermally holding it at 823 K (550 °C) for 2 h. Microstructural analysis shows the presence of porosity and unmelted particles on the as-sprayed surface, the area fraction of which reduces after heat treatment. X-ray diffraction analysis shows the phase transformation from anatase (in precursor powder) to rutile (in as-sprayed coating and the same after heat treatment). There is an improvement in nano-hardness, "Young's modulus" and wear resistance in plasma-sprayed TiO2 coating (as-sprayed as well as post-heat-treated condition) as compared to as-received Ti-6Al-4V, though post-heat treatment offers a superior hardness, "young's modulus" and wear resistance as compared to as-sprayed coating. The corrosion behavior in "hank's solution" shows decrease in corrosion resistance after plasma spraying and post-heat treatment as compared to as-received substrate. A significant decrease in contact angle and improvement in bioactivity (in terms of apatite deposition) were observed in TiO2-coated surface as compared to as-received Ti-6Al-4V.

  14. Reliability evaluation of the Savannah River reactor leak detection system

    International Nuclear Information System (INIS)

    Daugherty, W.L.; Sindelar, R.L.; Wallace, I.T.

    1991-01-01

    The Savannah River Reactors have been in operation since the mid-1950's. The primary degradation mode for the primary coolant loop piping is intergranular stress corrosion cracking. The leak-before-break (LBB) capability of the primary system piping has been demonstrated as part of an overall structural integrity evaluation. One element of the LBB analyses is a reliability evaluation of the leak detection system. The most sensitive element of the leak detection system is the airborne tritium monitors. The presence of small amounts of tritium in the heavy water coolant provide the basis for a very sensitive system of leak detection. The reliability of the tritium monitors to properly identify a crack leaking at a rate of either 50 or 300 lb/day (0.004 or 0.023 gpm, respectively) has been characterized. These leak rates correspond to action points for which specific operator actions are required. High reliability has been demonstrated using standard fault tree techniques. The probability of not detecting a leak within an assumed mission time of 24 hours is estimated to be approximately 5 x 10 -5 per demand. This result is obtained for both leak rates considered. The methodology and assumptions used to obtain this result are described in this paper. 3 refs., 1 fig., 1 tab

  15. Leak testing requirements at a research facility

    International Nuclear Information System (INIS)

    Conner, J.B.

    1979-01-01

    Since September, 1952, Lawrence Livermore Laboratory has conducted pioneering research in applied science. A vital part of this activity has been the development of a variety of high vacuum and ultrahigh vacuum systems. Leaks occur in everything, including vacuum systems. The mass spectrometer leak detection equipment is described

  16. Production of cocrystals in an excipient matrix by spray drying.

    Science.gov (United States)

    Walsh, David; Serrano, Dolores R; Worku, Zelalem Ayenew; Norris, Brid A; Healy, Anne Marie

    2018-01-30

    Spray drying is a well-established scale-up technique for the production of cocrystals. However, to the best of our knowledge, the effect of introducing a third component into the feed solution during the spray drying process has never been investigated. Cocrystal formation in the presence of a third component by a one-step spray drying process has the potential to reduce the number of unit operations which are required to produce a final pharmaceutical product (e.g. by eliminating blending with excipient). Sulfadimidine (SDM), a poorly water soluble active pharmaceutical ingredient (API), and 4-aminosalicylic acid (4ASA), a hydrophilic molecule, were used as model drug and coformer respectively to form cocrystals by spray drying in the presence of a third component (excipient). The solubility of the cocrystal in the excipient was measured using a thermal analysis approach. Trends in measured solubility were in agreement with those determined by calculated Hansen Solubility Parameter (HSP) values. The ratio of cocrystal components to excipient was altered and cocrystal formation at different weight ratios was assessed. Cocrystal integrity was preserved when the cocrystal components were immiscible with the excipient, based on the difference in Hansen Solubility Parameters (HSP). For immiscible systems (difference in HSP > 9.6 MPa 0.5 ), cocrystal formation occurred even when the proportion of excipient was high (90% w/w). When the excipient was partly miscible with the cocrystal components, cocrystal formation was observed post spray drying, but crystalline API and coformer were also recovered in the processed powder. An amorphous dispersion was formed when the excipient was miscible with the cocrystal components even when the proportion of excipient used as low (10% w/w excipient). For selected spray dried cocrystal-excipient systems an improvement in tableting characteristics was observed, relative to equivalent physical mixtures. Copyright © 2017 Elsevier

  17. Substrate system for spray forming

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Men G. (Export, PA); Chernicoff, William P. (Harrisburg, PA)

    2002-01-01

    A substrate system for receiving a deposit of sprayed metal droplets including a movable outer substrate on which the sprayed metal droplets are deposited. The substrate system also includes an inner substrate disposed adjacent the outer substrate where the sprayed metal droplets are deposited on the outer substrate. The inner substrate includes zones of differing thermal conductivity to resist substrate layer porosity and to resist formation of large grains and coarse constituent particles in a bulk layer of the metal droplets which have accumulated on the outer substrate. A spray forming apparatus and associated method of spray forming a molten metal to form a metal product using the substrate system of the invention is also provided.

  18. Autogenous Metallic Pipe Leak Repair in Potable Water Systems.

    Science.gov (United States)

    Tang, Min; Triantafyllidou, Simoni; Edwards, Marc A

    2015-07-21

    Copper and iron pipes have a remarkable capability for autogenous repair (self-repair) of leaks in potable water systems. Field studies revealed exemplars that metallic pipe leaks caused by nails, rocks, and erosion corrosion autogenously repaired, as confirmed in the laboratory experiments. This work demonstrated that 100% (N = 26) of 150 μm leaks contacting representative bulk potable water in copper pipes sealed autogenously via formation of corrosion precipitates at 20-40 psi, pH 3.0-11.0, and with upward and downward leak orientations. Similar leaks in carbon steel pipes at 20 psi self-repaired at pH 5.5 and 8.5, but two leaks did not self-repair permanently at pH 11.0 suggesting that water chemistry may control the durability of materials that seal the leaks and therefore the permanence of repair. Larger 400 μm holes in copper pipes had much lower (0-33%) success of self-repair at pH 3.0-11.0, whereas all 400 μm holes in carbon steel pipes at 20 psi self-repaired at pH 4.0-11.0. Pressure tests indicated that some of the repairs created at 20-40 psi ambient pressure could withstand more than 100 psi without failure. Autogenous repair has implications for understanding patterns of pipe failures, extending the lifetime of decaying infrastructure, and developing new plumbing materials.

  19. Characterization of Sodium Spray Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C. T.; Koontz, R. L.; Silberberg, M. [Atomics International, North American Rockwell Corporation, Canoga Park, CA (United States)

    1968-12-15

    The consequences of pool and spray fires require evaluation in the safety analysis of liquid metal-cooled fast breeder reactors. Sodium spray fires are characterized by high temperature and pressure, produced during the rapid combustion of sodium in air. Following the initial energy release, some fraction of the reaction products are available as aerosols which follow the normal laws of agglomeration, growth, settling, and plating. An experimental study is underway at Atomics International to study the characteristics of high concentration sprays of liquid sodium in reduced oxygen atmospheres and in air. The experiments are conducted in a 31.5 ft{sup 3} (2 ft diam. by 10 ft high) vessel, certified for a pressure of 100 lb/in{sup 2} (gauge). The spray injection apparatus consists of a heated sodium supply pot and a spray nozzle through which liquid sodium is driven by nitrogen pressure. Spray rate and droplet size can be varied by the injection velocity (nozzle size, nitrogen pressure, and sodium temperature). Aerosols produced in 0, 4, and 10 vol. % oxygen environments have been studied. The concentration and particle size distribution of the material remaining in the air after the spray injection and reaction period are measured. Fallout rates are found to be proportional to the concentration of aerosol which remains airborne following the spray period. (author)

  20. Improved bonding strength of bioactive cermet Cold Gas Spray coatings.

    Science.gov (United States)

    Gardon, M; Concustell, A; Dosta, S; Cinca, N; Cano, I G; Guilemany, J M

    2014-12-01

    The fabrication of cermet biocompatible coatings by means Cold Gas Spray (CGS) provides prosthesis with outstanding mechanical properties and the required composition for enhancing the bioactivity of prosthetic materials. In this study, hydroxyapatite/Titanium coatings were deposited by means of CGS technology onto titanium alloy substrates with the aim of building-up well-bonded homogeneous coatings. Powders were blended in different percentages and sprayed; as long as the amount of hydroxyapatite in the feedstock increased, the quality of the coating was reduced. Besides, the relation between the particle size distribution of ceramic and metallic particles is of significant consideration. Plastic deformation of titanium particles at the impact eased the anchoring of hard hydroxyapatite particles present at the top surface of the coating, which assures the looked-for interaction with the cells. Coatings were immersed in Hank's solution for 1, 4 and 7 days; bonding strength value was above 60 MPa even after 7 days, which enhances common results of HAp coatings obtained by conventional thermal spray technologies. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Development of evaluation method of long-term confinement performance for canister. Part 1. Fundamental study of analyses method for helium leak detection

    International Nuclear Information System (INIS)

    Takeda, Hirofumi; Toriu, Daisuke; Ushijima, Satoru

    2014-01-01

    The storage management of spent nuclear fuel for ageing degradation is becoming a global issue, so we researched the present status and measures of the management in each country. In particular, for the concrete cask storage, a leak detecting method that detects the leak from the change in canister surface temperature has been proposed. We performed thermal hydraulics analysis to clarify the phenomenon and to work toward practical use of the detecting method. For analyzing the leak phenomenon with high accuracy, it is necessary to stably solve the low-Mach number flow problem considering compressibility of gas. Therefore, we originally modified the conventional compressible flow solution method and proposed a new method which is applicable to thermo-hydraulics phenomenon and satisfies the mass conservation law with high accuracy. For the cavity natural convection analysis, the mass conservation in a calculating area was satisfied with high accuracy. As for the analysis of leak from the cavity, a helium leak phenomenon could be calculated stably by using the proposed method. The pressure in the cavity and the change of the mass could be also analyzed validly. As for the temperature distribution in the cavity, it was confirmed that the temperature changes before and after the leak. (author)

  2. A spray flamelet/progress variable approach combined with a transported joint PDF model for turbulent spray flames

    Science.gov (United States)

    Hu, Yong; Olguin, Hernan; Gutheil, Eva

    2017-05-01

    A spray flamelet/progress variable approach is developed for use in spray combustion with partly pre-vaporised liquid fuel, where a laminar spray flamelet library accounts for evaporation within the laminar flame structures. For this purpose, the standard spray flamelet formulation for pure evaporating liquid fuel and oxidiser is extended by a chemical reaction progress variable in both the turbulent spray flame model and the laminar spray flame structures, in order to account for the effect of pre-vaporised liquid fuel for instance through use of a pilot flame. This new approach is combined with a transported joint probability density function (PDF) method for the simulation of a turbulent piloted ethanol/air spray flame, and the extension requires the formulation of a joint three-variate PDF depending on the gas phase mixture fraction, the chemical reaction progress variable, and gas enthalpy. The molecular mixing is modelled with the extended interaction-by-exchange-with-the-mean (IEM) model, where source terms account for spray evaporation and heat exchange due to evaporation as well as the chemical reaction rate for the chemical reaction progress variable. This is the first formulation using a spray flamelet model considering both evaporation and partly pre-vaporised liquid fuel within the laminar spray flamelets. Results with this new formulation show good agreement with the experimental data provided by A.R. Masri, Sydney, Australia. The analysis of the Lagrangian statistics of the gas temperature and the OH mass fraction indicates that partially premixed combustion prevails near the nozzle exit of the spray, whereas further downstream, the non-premixed flame is promoted towards the inner rich-side of the spray jet since the pilot flame heats up the premixed inner spray zone. In summary, the simulation with the new formulation considering the reaction progress variable shows good performance, greatly improving the standard formulation, and it provides new

  3. Application of leak-before-break criteria to pressurized water reactors

    International Nuclear Information System (INIS)

    Roege, P.; Day, B.; Beckjord, E.; Golay, M.

    1986-01-01

    The possibility of consequential damage to safety-related systems or components after postulated pipe breaks in Light Water Reactors has led to the installation of pipe restraints capable of withstanding the loads in such an accident. These restraints are a significant part of initial capital cost, and because of their size and location, impede plant maintenance. The Piping Review Committee of the U.S. Nuclear Regulatory Commission has concluded that, subject to fulfillment of certain criteria, the pipe restraints for pressurized water reactor main coolant piping are not necessary, because the failure mode of this piping is such that it will leak before it will break, and the leakage of reactor coolant is large enough to detect. In this study, we examine the piping systems of a 4-loop 1,150 MWe pressurized water reactor, determining the crack size that would be stable from a fracture mechanics point of view, and the range of leak rates that would ensue. We then consider the sensitivity of conventional leak detection systems, and find that pipe sizes down to 45 cm in diameter would meet the leak-before-break criteria. Improvements in the sensitivity of conventional leak detectors would extend this range down to pipe sizes down to the range of 20 - 45 cm in diameter. The development of local leak detection systems which would respond to leaks in compartments or confined areas would make it possible to apply the criteria to sizes as low as 10 - 20 cm in diameter, which appear to be the limit of the net cost savings of eliminating pipe restraints and adding additional leak detection instrumentation. Extending the leak-before-break concept into this smallest pipe range may require improved precision in crack definition, flow modeling, and leak detection. Better detection of leaks may also require use of new detection methods coupled to novel approaches to piping system design. (J.P.N.)

  4. Leak testing using helium leak detector

    International Nuclear Information System (INIS)

    Aparicio, G.; Mathot, S.; Munoz, C.; Orlando, O.

    1997-01-01

    Most of the equipment used in the industry and particularly in the nuclear activity need to be, vacuum or pressure tight, for operative and safety requirements. These devices have to satisfy particular regulations in order to be qualified by means of operating licences. One of the most efficient system to ensure leaktightnes is using a helium leak detector with a mass spectrometer. In this paper we show the equipment and the devices employed in fuel rods fabrication for CAREM project, and some typical material defects. Operating system and the sensitivity of this method is also described. (author) [es

  5. Acoustic detection for water/steam leak from a tube of LMFBR steam generator

    International Nuclear Information System (INIS)

    Sonoda, Masataka; Shindo, Yoshihisa

    1989-01-01

    Acoustic leak detector is useful for detecting more quickly intermediate leak than the existing hydrogen detector and is available for identification of leak location on the accident of water/steam leak from a tube of LMFBR steam generator. This paper presents the overview of HALD (High frequency Acoustics Leak Detection) system, which is more sensitive for leak detection and lower cost of equipment for identification of leak location than a low frequency type detector. (author)

  6. Solution synthesis of mixed-metal chalcogenide nanoparticles and spray deposition of precursor films

    Science.gov (United States)

    Schulz, Douglas L.; Curtis, Calvin J.; Ginley, David S.

    2000-01-01

    A colloidal suspension comprising metal chalcogenide nanoparticles and a volatile capping agent. The colloidal suspension is made by reacting a metal salt with a chalcogenide salt in an organic solvent to precipitate a metal chalcogenide, recovering the metal chalcogenide, and admixing the metal chalcogenide with a volatile capping agent. The colloidal suspension is spray deposited onto a substrate to produce a semiconductor precursor film which is substantially free of impurities.

  7. Location estimation method of steam leak in pipeline using leakage area analysis

    International Nuclear Information System (INIS)

    Kim, Se Oh; Jeon, Hyeong Seop; Son, Ki Sung; Park, Jong Won

    2016-01-01

    It is important to have a pipeline leak-detection system that determines the presence of a leak and quickly identifies its location. Current leak detection methods use a acoustic emission sensors, microphone arrays, and camera images. Recently, many researchers have been focusing on using cameras for detecting leaks. The advantage of this method is that it can survey a wide area and monitor a pipeline over a long distance. However, conventional methods using camera monitoring are unable to target an exact leak location. In this paper, we propose a method of detecting leak locations using leak-detection results combined with multi-frame analysis. The proposed method is verified by experiment

  8. Location estimation method of steam leak in pipeline using leakage area analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Se Oh; Jeon, Hyeong Seop; Son, Ki Sung [Sae An Engineering Corp., Seoul (Korea, Republic of); Park, Jong Won [Dept. of Information Communications Engineering, Chungnam National University, Daejeon (Korea, Republic of)

    2016-10-15

    It is important to have a pipeline leak-detection system that determines the presence of a leak and quickly identifies its location. Current leak detection methods use a acoustic emission sensors, microphone arrays, and camera images. Recently, many researchers have been focusing on using cameras for detecting leaks. The advantage of this method is that it can survey a wide area and monitor a pipeline over a long distance. However, conventional methods using camera monitoring are unable to target an exact leak location. In this paper, we propose a method of detecting leak locations using leak-detection results combined with multi-frame analysis. The proposed method is verified by experiment.

  9. Materials as inherent ignition sources for dust explosions during spray drying

    NARCIS (Netherlands)

    Hoogenband, V. van den; Maaijer, M. de; Versloot, N.H.A.

    2010-01-01

    During spray drying where a solution is dispersed in small droplets through a nozzle the liquid evaporates by means of hot air. In a large number of these processes organic materials are processed so three out of four factors for dust explosions to occur are already present. The only thing missing

  10. Sealing of leaks in the bioshield cooling system of three research reactors

    International Nuclear Information System (INIS)

    May, R.; Taylor, M.F.

    1995-01-01

    Water leaks have occurred in the bioshield cooling system of three research reactors. These leaks have been plugged with a sealant based on a blend of a water-based resin and a bentonite-type clay originally developed for sealing similar leaks on power reactors. The mechanism of sealing and development testing of the sealant are described. Application of the sealant to the three reactors sealed the leaks. However, unlike experience with leaks in steel and aluminium systems, some leaks reappeared after several months service - albeit at a leak rate only a very small fraction of the original leak rate. The recurrent defects were readily retreated with sealant and hence, in these instances, the treatment is an effective maintenance procedure for any ageing reactor rather than a permanent cure. (orig.)

  11. Measurement of Submerged Oil/Gas Leaks using ROV Video

    Science.gov (United States)

    Shaffer, Franklin; de Vera, Giorgio; Lee, Kenneth; Savas, Ömer

    2013-11-01

    Drilling for oil or gas in the Gulf of Mexico is increasing rapidly at depths up to three miles. The National Commission on the Deepwater Horizon Oil Leak concluded that inaccurate estimates of the leak rate from the Deepwater Horizon caused an inadequate response and attempts to cap the leak to fail. The first response to a submerged oil/gas leak will be to send a Remotely Operated Vehicle (ROV) down to view the leak. During the response to the Deepwater Horizon crisis, the authors Savas and Shaffer were members of the Flow Rate Technical Group's Plume Team who used ROV video to develop the FRTG's first official estimates of the oil leak rate. Savas and Shaffer developed an approach using the larger, faster jet features (e.g., turbulent eddies, vortices, entrained particles) in the near-field developing zone to measure discharge rates. The authors have since used the Berkeley Tow Tank to test this approach on submerged dye-colored water jets and compressed air jets. Image Correlation Velocimetry has been applied to measure the velocity of visible features. Results from tests in the Berkeley Tow Tank and submerged oil jets in the OHMSETT facility will be presented.

  12. Local Leak Detection and Health Monitoring of Pressurized Tanks

    Science.gov (United States)

    Polzin, Kurt; Witherow, William; Korman, Valentin; Sinko, John; Hendrickson, Adam

    2011-01-01

    An optical gas-detection sensor safely monitors pressurized systems (such as cryogenic tanks) and distribution systems for leaks. This sensor system is a fiber-coupled, solid optical body interferometer that allows for the miniaturized sensing element of the device to be placed in the smallest of recesses, and measures a wide range of gas species and densities (leaks). The deflection of the fringe pattern is detected and recorded to yield the time-varying gas density in the gap. This technology can be used by manufacturers or storage facilities with toxic, hazardous, or explosive gases. The approach is to monitor the change in the index of refraction associated with low-level gas leaks into a vacuum environment. The completion of this work will provide NASA with an enabling capability to detect gas system leaks in space, and to verify that pressurized systems are in a safe (i.e. non-leaking) condition during manned docking and transit operations. By recording the output of the sensor, a time-history of the leak can be constructed to indicate its severity. Project risk is mitigated by having several interferometric geometries and detection techniques available, each potentially leveraging hardware and lessons learned to enhance detectability.

  13. Does the type of pancreaticojejunostomy after Whipple alter the leak rate?

    Science.gov (United States)

    Ball, Chad G; Howard, Thomas J

    2010-01-01

    Despite the overwhelming limitations that plague the literature surrounding the optimal method of reestablishing pancreatico-enteric continuity following a Whipple operation, it is clear that all successful techniques conform to sound surgical principles. These principles include a water-tight and tension-free anastomosis, preservation of adequate blood supply for both organs involved in the anastomosis, and minimal trauma to the pancreas gland. Although surgeon experience, gland texture, and pancreatic duct size are clearly the dominate risk factors from a long list of variables associated with pancreatic leaks following pancreatoduodenectomy, these are nonmodifiable covariates. Although the plethora of current literature cannot provide a single definitive technical solution for restoring pancreatico-enteric continuity, a small number of well-designed RCTs support the use of transanastomotic external stenting for high-risk pancreatic glands and an end-to-side invaginated pancreaticojejunostomy. The truth remains that an individual surgeon's mastery of a specific anastomotic technique, in conjunction with a large personal experience, is likely to be the best predictor of a low pancreas leak rate following pancreatoduodenectomy.

  14. Fabrication of ZnO nanorod using spray-pyrolysis and chemical bath deposition method

    Energy Technology Data Exchange (ETDEWEB)

    Ramadhani, Muhammad F., E-mail: brian@tf.itb.ac.id; Pasaribu, Maruli A. H., E-mail: brian@tf.itb.ac.id; Yuliarto, Brian, E-mail: brian@tf.itb.ac.id; Nugraha, E-mail: brian@tf.itb.ac.id [Advanced Functional Materials Laboratory, Engineering Physics Department Faculty of Industrial Technology, Institut Teknologi Bandung (Indonesia)

    2014-02-24

    ZnO thin films with nanorod structure were deposited using Ultrasonic Spray Pyrolysis method for seed growth, and Chemical Bath Deposition (CBD) for nanorod growth. High purity Zn-hydrate and Urea are used to control Ph were dissolved in ethanol and aqua bidest in Ultrasonic Spray Pyrolysis process. Glass substrate was placed above the heater plate of reaction chamber, and subsequently sprayed with the range duration of 5, 10 and 20 minutes at the temperatures of 3500 C. As for the Chemical Bath Deposition, the glass substrate with ZnO seed on the surface was immerse to Zn-hydrate, HMTA (Hexa Methylene Tetra Amine) and deionized water solution for duration of 3, 5 and 7 hour and temperatures of 600 C, washed in distilled water, dried, and annealed at 3500 C for an hour. The characterization of samples was carried out to reveal the surface morphology using Scanning Electron Microscopy (SEM). From the data, the combination of 5 minutes of Ultrasonic Spray Pyrolysis process and 3 hour of CBD has showed the best structure of nanorod. Meanwhile the longer Spraying process and CBD yield the bigger nanorod structure that have been made, and it makes the films more dense which make the nanorod collide each other and as a result produce unsymetric nanorod structure.

  15. Detection of Leaks in Water Distribution System using Non-Destructive Techniques

    Science.gov (United States)

    Aslam, H.; Kaur, M.; Sasi, S.; Mortula, Md M.; Yehia, S.; Ali, T.

    2018-05-01

    Water is scarce and needs to be conserved. A considerable amount of water which flows in the water distribution systems was found to be lost due to pipe leaks. Consequently, innovations in methods of pipe leakage detections for early recognition and repair of these leaks is vital to ensure minimum wastage of water in distribution systems. A major component of detection of pipe leaks is the ability to accurately locate the leak location in pipes through minimum invasion. Therefore, this paper studies the leak detection abilities of the three NDT’s: Ground Penetration Radar (GPR) and spectrometer and aims at determining whether these instruments are effective in identifying the leak. An experimental setup was constructed to simulate the underground conditions of water distribution systems. After analysing the experimental data, it was concluded that both the GPR and the spectrometer were effective in detecting leaks in the pipes. However, the results obtained from the spectrometer were not very differentiating in terms of observing the leaks in comparison to the results obtained from the GPR. In addition to this, it was concluded that both instruments could not be used if the water from the leaks had reached on the surface, resulting in surface ponding.

  16. New helium sniffing device for locating very fine leaks

    International Nuclear Information System (INIS)

    Murakami, Y.; Shimomura, Y.; Abe, T.; Obara, K.

    1984-01-01

    A new helium sniffing method for leak checking large vacuum vessels is described. The low sensitivity problem of the conventional helium sniffing method has been overcome by increasing the gas draw rate from around leaks into the detector up to about 0.1 Pa m 3 /s. The devised system consists of a flexible stainless steel capillary tube 0.6 mm i.d. and 10 m long, a sorption pump using molecular sieve, and a helium leak detector in series. This method is particularly useful for locating very fine leaks down to 10 -11 Pa m 3 /s. Relevant theoretical considerations and experimental results are presented

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

    Directory of Open Access Journals (Sweden)

    D. Thirumalaikumarasamy

    2014-12-01

    Full Text Available 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 wt% NaCl solution. Empirical relationship was established to predict the corrosion rate of plasma sprayed alumina coatings by incorporating process parameters. The experiments were conducted based on a three factor, five-level, central composite rotatable design matrix. The developed relationship can be effectively used to predict the corrosion rate of alumina coatings at 95% confidence level. The results indicate that the input power has the greatest influence on corrosion rate, followed by stand-off distance and powder feed rate.

  18. Chemical pleurodesis using mistletoe extracts via spray catheter during medical thoracoscopy for management of malignant pleural effusion

    OpenAIRE

    Eom, Jung Seop; Kim, Tae Hwa; Lee, Geewon; Ahn, Hyo Yeong; Mok, Jeong Ha; Lee, Min Ki

    2017-01-01

    We present three cases of successful chemical pleurodesis with a liquid solution of mistletoe extract using a spray catheter during medical thoracoscopy. The medical thoracoscopy was performed in all presented cases to remove pleural effusion and conduct chemical pleurodesis to manage symptomatic malignant pleural effusion. A spray catheter was used to instil the mistletoe extract evenly into the pleural cavity, and there were no pleurodesis?related complications. Respiratory symptoms caused ...

  19. Improving tolerance of sunflower and safflower during growth stages to salinity through foliar spray of nutrient solutions

    International Nuclear Information System (INIS)

    Jabeen, N.; Ahmad, R.

    2012-01-01

    The effect of salinity and foliar application of nutrient solutions on sunflower and safflower in vegetative and reproductive phases of the growth were investigated in Bio saline Research Field, University of Karachi, Pakistan. The seeds were sown in pots under non saline condition and saline water irrigation was started at three leaf stage after germination. Different concentration of saline water were made by dissolving 3g and 6g sea salt per litre of tap water, equivalent to an EC of 4.8 and 8.6 dS/m respectively. Nutrient solution (KNO/sub 3 /, H/sub 3/ BO/sub 3/, Fe-EDTA or its mixture) was sprayed thrice, i.e., 45, 75 and 95 days after planting. KNO/sub 3/ was given at the rate 250 ppm and other H/sub 3/ BO/sub 3/ and Fe-EDTA was given at the rate 5 ppm. Salinity caused a significant reduction in nutrient uptake, height, biomass and yield of both sunflower and safflower. Foliar application of macro and micro nutrients (i.e. KNO/sub 3/, H/sub 3/BO/sub 3/, Fe-EDTA and mixture of KNO/sub 3/ + H/sub 3/BO/sub 3/ + Fe-EDTA) partially minimized the salt induced deficiency and showed significant increase in height, fresh and dry biomass, number and weight of seeds, and amount of oil per sunflower and safflower plant irrespective to their growth under non saline or saline conditions. Among the nutrient solutions, mixture of KNO/sub 3/+ H/sub 3/BO/sub 3/ + Fe-EDTA seemed to be the most effective followed by H/sub 3/ BO/sub 3/ and Fe-EDTA. These results suggested that foliar application of nutrients could be used to improve plant tolerance to salinity by alleviating the adverse effects of salinity on growth and reproductive yield. (author)

  20. The potential role of sea spray droplets in facilitating air-sea gas transfer

    Science.gov (United States)

    Andreas, E. L.; Vlahos, P.; Monahan, E. C.

    2016-05-01

    For over 30 years, air-sea interaction specialists have been evaluating and parameterizing the role of whitecap bubbles in air-sea gas exchange. To our knowledge, no one, however, has studied the mirror image process of whether sea spray droplets can facilitate air-sea gas exchange. We are therefore using theory, data analysis, and numerical modeling to quantify the role of spray on air-sea gas transfer. In this, our first formal work on this subject, we seek the rate-limiting step in spray-mediated gas transfer by evaluating the three time scales that govern the exchange: τ air , which quantifies the rate of transfer between the atmospheric gas reservoir and the surface of the droplet; τ int , which quantifies the exchange rate across the air-droplet interface; and τ aq , which quantifies gas mixing within the aqueous solution droplet.